reactos/ntoskrnl/mm/section.c

/*
 * Copyright (C) 1998-2005 ReactOS Team (and the authors from the programmers section)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 *
 * PROJECT:         ReactOS kernel
 * FILE:            ntoskrnl/mm/section.c
 * PURPOSE:         Implements section objects
 *
 * PROGRAMMERS:     Rex Jolliff
 *                  David Welch
 *                  Eric Kohl
 *                  Emanuele Aliberti
 *                  Eugene Ingerman
 *                  Casper Hornstrup
 *                  KJK::Hyperion
 *                  Guido de Jong
 *                  Ge van Geldorp
 *                  Royce Mitchell III
 *                  Filip Navara
 *                  Aleksey Bragin
 *                  Jason Filby
 *                  Thomas Weidenmueller
 *                  Gunnar Andre' Dalsnes
 *                  Mike Nordell
 *                  Alex Ionescu
 *                  Gregor Anich
 *                  Steven Edwards
 *                  Herve Poussineau
 */

/* INCLUDES *****************************************************************/

#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
#include <reactos/exeformat.h>

#if defined (ALLOC_PRAGMA)
#pragma alloc_text(INIT, MmCreatePhysicalMemorySection)
#pragma alloc_text(INIT, MmInitSectionImplementation)
#endif

NTSTATUS
NTAPI
MiMapViewInSystemSpace(IN PVOID Section,
IN PVOID Session,
OUT PVOID *MappedBase,
IN OUT PSIZE_T ViewSize);

NTSTATUS
NTAPI
MmCreateArm3Section(OUT PVOID *SectionObject,
IN ACCESS_MASK DesiredAccess,
IN POBJECT_ATTRIBUTES ObjectAttributes OPTIONAL,
IN PLARGE_INTEGER InputMaximumSize,
IN ULONG SectionPageProtection,
IN ULONG AllocationAttributes,
IN HANDLE FileHandle OPTIONAL,
IN PFILE_OBJECT FileObject OPTIONAL);

NTSTATUS
NTAPI
MmMapViewOfArm3Section(IN PVOID SectionObject,
                       IN PEPROCESS Process,
                       IN OUT PVOID *BaseAddress,
                       IN ULONG_PTR ZeroBits,
                       IN SIZE_T CommitSize,
                       IN OUT PLARGE_INTEGER SectionOffset OPTIONAL,
                       IN OUT PSIZE_T ViewSize,
                       IN SECTION_INHERIT InheritDisposition,
                       IN ULONG AllocationType,
                       IN ULONG Protect);
                       
//
// PeFmtCreateSection depends on the following:
//
C_ASSERT(EXEFMT_LOAD_HEADER_SIZE >= sizeof(IMAGE_DOS_HEADER));
C_ASSERT(sizeof(IMAGE_NT_HEADERS32) <= sizeof(IMAGE_NT_HEADERS64));

C_ASSERT(TYPE_ALIGNMENT(IMAGE_NT_HEADERS32) == TYPE_ALIGNMENT(IMAGE_NT_HEADERS64));
C_ASSERT(RTL_SIZEOF_THROUGH_FIELD(IMAGE_NT_HEADERS32, FileHeader) == RTL_SIZEOF_THROUGH_FIELD(IMAGE_NT_HEADERS64, FileHeader));
C_ASSERT(FIELD_OFFSET(IMAGE_NT_HEADERS32, OptionalHeader) == FIELD_OFFSET(IMAGE_NT_HEADERS64, OptionalHeader));

C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, Magic));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, SectionAlignment));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, FileAlignment));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, Subsystem));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, MinorSubsystemVersion));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, MajorSubsystemVersion));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, AddressOfEntryPoint));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, SizeOfCode));
C_ASSERT(PEFMT_FIELDS_EQUAL(IMAGE_OPTIONAL_HEADER32, IMAGE_OPTIONAL_HEADER64, SizeOfHeaders));

/* TYPES *********************************************************************/

typedef struct
{
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;
   ULONG Offset;
   BOOLEAN WasDirty;
   BOOLEAN Private;
}
MM_SECTION_PAGEOUT_CONTEXT;

/* GLOBALS *******************************************************************/

POBJECT_TYPE MmSectionObjectType = NULL;

SIZE_T MmAllocationFragment;

ULONG_PTR MmSubsectionBase;

static ULONG SectionCharacteristicsToProtect[16] =
{
    PAGE_NOACCESS,          /* 0 = NONE */
    PAGE_NOACCESS,          /* 1 = SHARED */
    PAGE_EXECUTE,           /* 2 = EXECUTABLE */
    PAGE_EXECUTE,           /* 3 = EXECUTABLE, SHARED */
    PAGE_READONLY,          /* 4 = READABLE */
    PAGE_READONLY,          /* 5 = READABLE, SHARED */
    PAGE_EXECUTE_READ,      /* 6 = READABLE, EXECUTABLE */
    PAGE_EXECUTE_READ,      /* 7 = READABLE, EXECUTABLE, SHARED */
    /*
     * FIXME? do we really need the WriteCopy field in segments? can't we use
     * PAGE_WRITECOPY here?
     */
    PAGE_READWRITE,         /* 8 = WRITABLE */
    PAGE_READWRITE,         /* 9 = WRITABLE, SHARED */
    PAGE_EXECUTE_READWRITE, /* 10 = WRITABLE, EXECUTABLE */
    PAGE_EXECUTE_READWRITE, /* 11 = WRITABLE, EXECUTABLE, SHARED */
    PAGE_READWRITE,         /* 12 = WRITABLE, READABLE */
    PAGE_READWRITE,         /* 13 = WRITABLE, READABLE, SHARED */
    PAGE_EXECUTE_READWRITE, /* 14 = WRITABLE, READABLE, EXECUTABLE */
    PAGE_EXECUTE_READWRITE, /* 15 = WRITABLE, READABLE, EXECUTABLE, SHARED */
};

static GENERIC_MAPPING MmpSectionMapping = {
         STANDARD_RIGHTS_READ | SECTION_MAP_READ | SECTION_QUERY,
         STANDARD_RIGHTS_WRITE | SECTION_MAP_WRITE,
         STANDARD_RIGHTS_EXECUTE | SECTION_MAP_EXECUTE,
         SECTION_ALL_ACCESS};

#define PAGE_FROM_SSE(E)         ((E) & 0xFFFFF000)
#define PFN_FROM_SSE(E)          ((E) >> PAGE_SHIFT)
#define SHARE_COUNT_FROM_SSE(E)  (((E) & 0x00000FFE) >> 1)
#define IS_SWAP_FROM_SSE(E)      ((E) & 0x00000001)
#define MAX_SHARE_COUNT          0x7FF
#define MAKE_SSE(P, C)           ((P) | ((C) << 1))
#define SWAPENTRY_FROM_SSE(E)    ((E) >> 1)
#define MAKE_SWAP_SSE(S)         (((S) << 1) | 0x1)

static const INFORMATION_CLASS_INFO ExSectionInfoClass[] =
{
  ICI_SQ_SAME( sizeof(SECTION_BASIC_INFORMATION), sizeof(ULONG), ICIF_QUERY ), /* SectionBasicInformation */
  ICI_SQ_SAME( sizeof(SECTION_IMAGE_INFORMATION), sizeof(ULONG), ICIF_QUERY ), /* SectionImageInformation */
};

/* FUNCTIONS *****************************************************************/


/*
 References:
  [1] Microsoft Corporation, "Microsoft Portable Executable and Common Object
      File Format Specification", revision 6.0 (February 1999)
*/
NTSTATUS NTAPI PeFmtCreateSection(IN CONST VOID * FileHeader,
				  IN SIZE_T FileHeaderSize,
				  IN PVOID File,
				  OUT PMM_IMAGE_SECTION_OBJECT ImageSectionObject,
				  OUT PULONG Flags,
				  IN PEXEFMT_CB_READ_FILE ReadFileCb,
				  IN PEXEFMT_CB_ALLOCATE_SEGMENTS AllocateSegmentsCb)
{
    NTSTATUS nStatus;
    ULONG cbFileHeaderOffsetSize = 0;
    ULONG cbSectionHeadersOffset = 0;
    ULONG cbSectionHeadersSize;
    ULONG cbSectionHeadersOffsetSize = 0;
    ULONG cbOptHeaderSize;
    ULONG cbHeadersSize = 0;
    ULONG nSectionAlignment;
    ULONG nFileAlignment;
    const IMAGE_DOS_HEADER * pidhDosHeader;
    const IMAGE_NT_HEADERS32 * pinhNtHeader;
    const IMAGE_OPTIONAL_HEADER32 * piohOptHeader;
    const IMAGE_SECTION_HEADER * pishSectionHeaders;
    PMM_SECTION_SEGMENT pssSegments;
    LARGE_INTEGER lnOffset;
    PVOID pBuffer;
    ULONG nPrevVirtualEndOfSegment = 0;
    ULONG nFileSizeOfHeaders = 0;
    ULONG i;

    ASSERT(FileHeader);
    ASSERT(FileHeaderSize > 0);
    ASSERT(File);
    ASSERT(ImageSectionObject);
    ASSERT(ReadFileCb);
    ASSERT(AllocateSegmentsCb);

    ASSERT(Intsafe_CanOffsetPointer(FileHeader, FileHeaderSize));

    ASSERT(((UINT_PTR)FileHeader % TYPE_ALIGNMENT(IMAGE_DOS_HEADER)) == 0);

#define DIE(ARGS_) { DPRINT ARGS_; goto l_Return; }

    pBuffer = NULL;
    pidhDosHeader = FileHeader;

    /* DOS HEADER */
    nStatus = STATUS_ROS_EXEFMT_UNKNOWN_FORMAT;

    /* image too small to be an MZ executable */
    if(FileHeaderSize < sizeof(IMAGE_DOS_HEADER))
	DIE(("Too small to be an MZ executable, size is %lu\n", FileHeaderSize));

    /* no MZ signature */
    if(pidhDosHeader->e_magic != IMAGE_DOS_SIGNATURE)
	DIE(("No MZ signature found, e_magic is %hX\n", pidhDosHeader->e_magic));

    /* not a Windows executable */
    if(pidhDosHeader->e_lfanew <= 0)
	DIE(("Not a Windows executable, e_lfanew is %d\n", pidhDosHeader->e_lfanew));

    /* NT HEADER */
    nStatus = STATUS_INVALID_IMAGE_FORMAT;

    if(!Intsafe_AddULong32(&cbFileHeaderOffsetSize, pidhDosHeader->e_lfanew, RTL_SIZEOF_THROUGH_FIELD(IMAGE_NT_HEADERS32, FileHeader)))
	DIE(("The DOS stub is too large, e_lfanew is %X\n", pidhDosHeader->e_lfanew));

    if(FileHeaderSize < cbFileHeaderOffsetSize)
	pinhNtHeader = NULL;
    else
    {
	/*
	 * we already know that Intsafe_CanOffsetPointer(FileHeader, FileHeaderSize),
	 * and FileHeaderSize >= cbFileHeaderOffsetSize, so this holds true too
	 */
	ASSERT(Intsafe_CanOffsetPointer(FileHeader, pidhDosHeader->e_lfanew));
	pinhNtHeader = (PVOID)((UINT_PTR)FileHeader + pidhDosHeader->e_lfanew);
    }

    /*
     * the buffer doesn't contain the NT file header, or the alignment is wrong: we
     * need to read the header from the file
     */
    if(FileHeaderSize < cbFileHeaderOffsetSize ||
       (UINT_PTR)pinhNtHeader % TYPE_ALIGNMENT(IMAGE_NT_HEADERS32) != 0)
    {
	ULONG cbNtHeaderSize;
	ULONG cbReadSize;
	PVOID pData;

l_ReadHeaderFromFile:
	cbNtHeaderSize = 0;
	lnOffset.QuadPart = pidhDosHeader->e_lfanew;

	/* read the header from the file */
	nStatus = ReadFileCb(File, &lnOffset, sizeof(IMAGE_NT_HEADERS64), &pData, &pBuffer, &cbReadSize);

	if(!NT_SUCCESS(nStatus))
	    DIE(("ReadFile failed, status %08X\n", nStatus));

	ASSERT(pData);
	ASSERT(pBuffer);
	ASSERT(cbReadSize > 0);

	nStatus = STATUS_INVALID_IMAGE_FORMAT;

	/* the buffer doesn't contain the file header */
	if(cbReadSize < RTL_SIZEOF_THROUGH_FIELD(IMAGE_NT_HEADERS32, FileHeader))
	    DIE(("The file doesn't contain the PE file header\n"));

	pinhNtHeader = pData;

	/* object still not aligned: copy it to the beginning of the buffer */
	if((UINT_PTR)pinhNtHeader % TYPE_ALIGNMENT(IMAGE_NT_HEADERS32) != 0)
	{
	    ASSERT((UINT_PTR)pBuffer % TYPE_ALIGNMENT(IMAGE_NT_HEADERS32) == 0);
	    RtlMoveMemory(pBuffer, pData, cbReadSize);
	    pinhNtHeader = pBuffer;
	}

	/* invalid NT header */
	nStatus = STATUS_INVALID_IMAGE_PROTECT;

	if(pinhNtHeader->Signature != IMAGE_NT_SIGNATURE)
	    DIE(("The file isn't a PE executable, Signature is %X\n", pinhNtHeader->Signature));

	nStatus = STATUS_INVALID_IMAGE_FORMAT;

	if(!Intsafe_AddULong32(&cbNtHeaderSize, pinhNtHeader->FileHeader.SizeOfOptionalHeader, FIELD_OFFSET(IMAGE_NT_HEADERS32, OptionalHeader)))
	    DIE(("The full NT header is too large\n"));

	/* the buffer doesn't contain the whole NT header */
	if(cbReadSize < cbNtHeaderSize)
	    DIE(("The file doesn't contain the full NT header\n"));
    }
    else
    {
	ULONG cbOptHeaderOffsetSize = 0;

	nStatus = STATUS_INVALID_IMAGE_FORMAT;

	/* don't trust an invalid NT header */
	if(pinhNtHeader->Signature != IMAGE_NT_SIGNATURE)
	    DIE(("The file isn't a PE executable, Signature is %X\n", pinhNtHeader->Signature));

	if(!Intsafe_AddULong32(&cbOptHeaderOffsetSize, pidhDosHeader->e_lfanew, FIELD_OFFSET(IMAGE_NT_HEADERS32, OptionalHeader)))
	    DIE(("The DOS stub is too large, e_lfanew is %X\n", pidhDosHeader->e_lfanew));

	if(!Intsafe_AddULong32(&cbOptHeaderOffsetSize, cbOptHeaderOffsetSize, pinhNtHeader->FileHeader.SizeOfOptionalHeader))
	    DIE(("The NT header is too large, SizeOfOptionalHeader is %X\n", pinhNtHeader->FileHeader.SizeOfOptionalHeader));

	/* the buffer doesn't contain the whole NT header: read it from the file */
	if(cbOptHeaderOffsetSize > FileHeaderSize)
	    goto l_ReadHeaderFromFile;
    }

    /* read information from the NT header */
    piohOptHeader = &pinhNtHeader->OptionalHeader;
    cbOptHeaderSize = pinhNtHeader->FileHeader.SizeOfOptionalHeader;

    nStatus = STATUS_INVALID_IMAGE_FORMAT;

    if(!RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, Magic))
	DIE(("The optional header doesn't contain the Magic field, SizeOfOptionalHeader is %X\n", cbOptHeaderSize));

    /* ASSUME: RtlZeroMemory(ImageSectionObject, sizeof(*ImageSectionObject)); */

    switch(piohOptHeader->Magic)
    {
	case IMAGE_NT_OPTIONAL_HDR32_MAGIC:
	case IMAGE_NT_OPTIONAL_HDR64_MAGIC:
	    break;

	default:
	    DIE(("Unrecognized optional header, Magic is %X\n", piohOptHeader->Magic));
    }

    if (RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, SectionAlignment) &&
        RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, FileAlignment))
    {
	/* See [1], section 3.4.2 */
	if(piohOptHeader->SectionAlignment < PAGE_SIZE)
	{
	    if(piohOptHeader->FileAlignment != piohOptHeader->SectionAlignment)
		DIE(("Sections aren't page-aligned and the file alignment isn't the same\n"));
	}
	else if(piohOptHeader->SectionAlignment < piohOptHeader->FileAlignment)
	    DIE(("The section alignment is smaller than the file alignment\n"));

	nSectionAlignment = piohOptHeader->SectionAlignment;
	nFileAlignment = piohOptHeader->FileAlignment;

	if(!IsPowerOf2(nSectionAlignment) || !IsPowerOf2(nFileAlignment))
	    DIE(("The section alignment (%u) and file alignment (%u) aren't both powers of 2\n", nSectionAlignment, nFileAlignment));
    }
    else
    {
	nSectionAlignment = PAGE_SIZE;
	nFileAlignment = PAGE_SIZE;
    }

    ASSERT(IsPowerOf2(nSectionAlignment));
    ASSERT(IsPowerOf2(nFileAlignment));

    switch(piohOptHeader->Magic)
    {
	/* PE32 */
	case IMAGE_NT_OPTIONAL_HDR32_MAGIC:
	{
	    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, ImageBase))
		ImageSectionObject->ImageBase = piohOptHeader->ImageBase;

	    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, SizeOfImage))
		ImageSectionObject->ImageSize = piohOptHeader->SizeOfImage;

	    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, SizeOfStackReserve))
		ImageSectionObject->StackReserve = piohOptHeader->SizeOfStackReserve;

	    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, SizeOfStackCommit))
		ImageSectionObject->StackCommit = piohOptHeader->SizeOfStackCommit;

	    break;
	}

	/* PE32+ */
	case IMAGE_NT_OPTIONAL_HDR64_MAGIC:
	{
	    const IMAGE_OPTIONAL_HEADER64 * pioh64OptHeader;

	    pioh64OptHeader = (const IMAGE_OPTIONAL_HEADER64 *)piohOptHeader;

	    if(RTL_CONTAINS_FIELD(pioh64OptHeader, cbOptHeaderSize, ImageBase))
	    {
		if(pioh64OptHeader->ImageBase > MAXULONG_PTR)
		    DIE(("ImageBase exceeds the address space\n"));

		ImageSectionObject->ImageBase = (ULONG_PTR)pioh64OptHeader->ImageBase;
	    }

	    if(RTL_CONTAINS_FIELD(pioh64OptHeader, cbOptHeaderSize, SizeOfImage))
	    {
		if(pioh64OptHeader->SizeOfImage > MAXULONG_PTR)
		    DIE(("SizeOfImage exceeds the address space\n"));

		ImageSectionObject->ImageSize = pioh64OptHeader->SizeOfImage;
	    }

	    if(RTL_CONTAINS_FIELD(pioh64OptHeader, cbOptHeaderSize, SizeOfStackReserve))
	    {
		if(pioh64OptHeader->SizeOfStackReserve > MAXULONG_PTR)
		    DIE(("SizeOfStackReserve exceeds the address space\n"));

		ImageSectionObject->StackReserve = pioh64OptHeader->SizeOfStackReserve;
	    }

	    if(RTL_CONTAINS_FIELD(pioh64OptHeader, cbOptHeaderSize, SizeOfStackCommit))
	    {
		if(pioh64OptHeader->SizeOfStackCommit > MAXULONG_PTR)
		    DIE(("SizeOfStackCommit exceeds the address space\n"));

		ImageSectionObject->StackCommit = pioh64OptHeader->SizeOfStackCommit;
	    }

	    break;
	}
    }

    /* [1], section 3.4.2 */
    if((ULONG_PTR)ImageSectionObject->ImageBase % 0x10000)
	DIE(("ImageBase is not aligned on a 64KB boundary"));

    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, Subsystem))
    {
	ImageSectionObject->Subsystem = piohOptHeader->Subsystem;

	if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, MinorSubsystemVersion) &&
	   RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, MajorSubsystemVersion))
	{
	    ImageSectionObject->MinorSubsystemVersion = piohOptHeader->MinorSubsystemVersion;
	    ImageSectionObject->MajorSubsystemVersion = piohOptHeader->MajorSubsystemVersion;
	}
    }

    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, AddressOfEntryPoint))
    {
	ImageSectionObject->EntryPoint = piohOptHeader->ImageBase +
                                         piohOptHeader->AddressOfEntryPoint;
    }

    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, SizeOfCode))
	ImageSectionObject->Executable = piohOptHeader->SizeOfCode != 0;
    else
	ImageSectionObject->Executable = TRUE;

    ImageSectionObject->ImageCharacteristics = pinhNtHeader->FileHeader.Characteristics;
    ImageSectionObject->Machine = pinhNtHeader->FileHeader.Machine;

    /* SECTION HEADERS */
    nStatus = STATUS_INVALID_IMAGE_FORMAT;

    /* see [1], section 3.3 */
    if(pinhNtHeader->FileHeader.NumberOfSections > 96)
	DIE(("Too many sections, NumberOfSections is %u\n", pinhNtHeader->FileHeader.NumberOfSections));

    /*
     * the additional segment is for the file's headers. They need to be present for
     * the benefit of the dynamic loader (to locate exports, defaults for thread
     * parameters, resources, etc.)
     */
    ImageSectionObject->NrSegments = pinhNtHeader->FileHeader.NumberOfSections + 1;

    /* file offset for the section headers */
    if(!Intsafe_AddULong32(&cbSectionHeadersOffset, pidhDosHeader->e_lfanew, FIELD_OFFSET(IMAGE_NT_HEADERS32, OptionalHeader)))
	DIE(("Offset overflow\n"));

    if(!Intsafe_AddULong32(&cbSectionHeadersOffset, cbSectionHeadersOffset, pinhNtHeader->FileHeader.SizeOfOptionalHeader))
	DIE(("Offset overflow\n"));

    /* size of the section headers */
    ASSERT(Intsafe_CanMulULong32(pinhNtHeader->FileHeader.NumberOfSections, sizeof(IMAGE_SECTION_HEADER)));
    cbSectionHeadersSize = pinhNtHeader->FileHeader.NumberOfSections * sizeof(IMAGE_SECTION_HEADER);

    if(!Intsafe_AddULong32(&cbSectionHeadersOffsetSize, cbSectionHeadersOffset, cbSectionHeadersSize))
	DIE(("Section headers too large\n"));

    /* size of the executable's headers */
    if(RTL_CONTAINS_FIELD(piohOptHeader, cbOptHeaderSize, SizeOfHeaders))
    {
//	if(!IsAligned(piohOptHeader->SizeOfHeaders, nFileAlignment))
//	    DIE(("SizeOfHeaders is not aligned\n"));

	if(cbSectionHeadersSize > piohOptHeader->SizeOfHeaders)
	    DIE(("The section headers overflow SizeOfHeaders\n"));

	cbHeadersSize = piohOptHeader->SizeOfHeaders;
    }
    else if(!AlignUp(&cbHeadersSize, cbSectionHeadersOffsetSize, nFileAlignment))
	DIE(("Overflow aligning the size of headers\n"));

    if(pBuffer)
    {
	ExFreePool(pBuffer);
	pBuffer = NULL;
    }
    /* WARNING: pinhNtHeader IS NO LONGER USABLE */
    /* WARNING: piohOptHeader IS NO LONGER USABLE */
    /* WARNING: pioh64OptHeader IS NO LONGER USABLE */

    if(FileHeaderSize < cbSectionHeadersOffsetSize)
	pishSectionHeaders = NULL;
    else
    {
	/*
	 * we already know that Intsafe_CanOffsetPointer(FileHeader, FileHeaderSize),
	 * and FileHeaderSize >= cbSectionHeadersOffsetSize, so this holds true too
	 */
	ASSERT(Intsafe_CanOffsetPointer(FileHeader, cbSectionHeadersOffset));
	pishSectionHeaders = (PVOID)((UINT_PTR)FileHeader + cbSectionHeadersOffset);
    }

    /*
     * the buffer doesn't contain the section headers, or the alignment is wrong:
     * read the headers from the file
     */
    if(FileHeaderSize < cbSectionHeadersOffsetSize ||
       (UINT_PTR)pishSectionHeaders % TYPE_ALIGNMENT(IMAGE_SECTION_HEADER) != 0)
    {
	PVOID pData;
	ULONG cbReadSize;

	lnOffset.QuadPart = cbSectionHeadersOffset;

	/* read the header from the file */
	nStatus = ReadFileCb(File, &lnOffset, cbSectionHeadersSize, &pData, &pBuffer, &cbReadSize);

	if(!NT_SUCCESS(nStatus))
	    DIE(("ReadFile failed with status %08X\n", nStatus));

	ASSERT(pData);
	ASSERT(pBuffer);
	ASSERT(cbReadSize > 0);

	nStatus = STATUS_INVALID_IMAGE_FORMAT;

	/* the buffer doesn't contain all the section headers */
	if(cbReadSize < cbSectionHeadersSize)
	    DIE(("The file doesn't contain all of the section headers\n"));

	pishSectionHeaders = pData;

	/* object still not aligned: copy it to the beginning of the buffer */
	if((UINT_PTR)pishSectionHeaders % TYPE_ALIGNMENT(IMAGE_SECTION_HEADER) != 0)
	{
	    ASSERT((UINT_PTR)pBuffer % TYPE_ALIGNMENT(IMAGE_SECTION_HEADER) == 0);
	    RtlMoveMemory(pBuffer, pData, cbReadSize);
	    pishSectionHeaders = pBuffer;
	}
    }

    /* SEGMENTS */
    /* allocate the segments */
    nStatus = STATUS_INSUFFICIENT_RESOURCES;
    ImageSectionObject->Segments = AllocateSegmentsCb(ImageSectionObject->NrSegments);

    if(ImageSectionObject->Segments == NULL)
	DIE(("AllocateSegments failed\n"));

    /* initialize the headers segment */
	pssSegments = ImageSectionObject->Segments;

//  ASSERT(IsAligned(cbHeadersSize, nFileAlignment));

    if(!AlignUp(&nFileSizeOfHeaders, cbHeadersSize, nFileAlignment))
	DIE(("Cannot align the size of the section headers\n"));

    if(!AlignUp(&nPrevVirtualEndOfSegment, cbHeadersSize, nSectionAlignment))
	DIE(("Cannot align the size of the section headers\n"));

    pssSegments[0].FileOffset = 0;
    pssSegments[0].Protection = PAGE_READONLY;
    pssSegments[0].Length = nPrevVirtualEndOfSegment;
    pssSegments[0].RawLength = nFileSizeOfHeaders;
    pssSegments[0].VirtualAddress = 0;
    pssSegments[0].Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA;
    pssSegments[0].WriteCopy = TRUE;

    /* skip the headers segment */
    ++ pssSegments;

    nStatus = STATUS_INVALID_IMAGE_FORMAT;

    /* convert the executable sections into segments. See also [1], section 4 */
    for(i = 0; i < ImageSectionObject->NrSegments - 1; ++ i)
    {
	ULONG nCharacteristics;

	/* validate the alignment */
	if(!IsAligned(pishSectionHeaders[i].VirtualAddress, nSectionAlignment))
	    DIE(("VirtualAddress[%u] is not aligned\n", i));

	/* sections must be contiguous, ordered by base address and non-overlapping */
	if(pishSectionHeaders[i].VirtualAddress != nPrevVirtualEndOfSegment)
	    DIE(("Memory gap between section %u and the previous\n", i));

	/* ignore explicit BSS sections */
	if(pishSectionHeaders[i].SizeOfRawData != 0)
	{
	    /* validate the alignment */
#if 0
	    /* Yes, this should be a multiple of FileAlignment, but there's
	     * stuff out there that isn't. We can cope with that
	     */
	    if(!IsAligned(pishSectionHeaders[i].SizeOfRawData, nFileAlignment))
		DIE(("SizeOfRawData[%u] is not aligned\n", i));
#endif

//	    if(!IsAligned(pishSectionHeaders[i].PointerToRawData, nFileAlignment))
//		DIE(("PointerToRawData[%u] is not aligned\n", i));

	    /* conversion */
	    pssSegments[i].FileOffset = pishSectionHeaders[i].PointerToRawData;
	    pssSegments[i].RawLength = pishSectionHeaders[i].SizeOfRawData;
	}
	else
	{
	    ASSERT(pssSegments[i].FileOffset == 0);
	    ASSERT(pssSegments[i].RawLength == 0);
	}

	ASSERT(Intsafe_CanAddLong64(pssSegments[i].FileOffset, pssSegments[i].RawLength));

	nCharacteristics = pishSectionHeaders[i].Characteristics;

	/* no explicit protection */
	if((nCharacteristics & (IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE)) == 0)
	{
	    if(nCharacteristics & IMAGE_SCN_CNT_CODE)
		nCharacteristics |= IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ;

	    if(nCharacteristics & IMAGE_SCN_CNT_INITIALIZED_DATA)
		nCharacteristics |= IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE;

	    if(nCharacteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA)
		nCharacteristics |= IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE;
	}

	/* see table above */
	pssSegments[i].Protection = SectionCharacteristicsToProtect[nCharacteristics >> 28];
	pssSegments[i].WriteCopy = !(nCharacteristics & IMAGE_SCN_MEM_SHARED);

	if(pishSectionHeaders[i].Misc.VirtualSize == 0 || pishSectionHeaders[i].Misc.VirtualSize < pishSectionHeaders[i].SizeOfRawData)
	    pssSegments[i].Length = pishSectionHeaders[i].SizeOfRawData;
	else
	    pssSegments[i].Length = pishSectionHeaders[i].Misc.VirtualSize;

	if(!AlignUp(&pssSegments[i].Length, pssSegments[i].Length, nSectionAlignment))
	    DIE(("Cannot align the virtual size of section %u\n", i));

	ASSERT(IsAligned(pssSegments[i].Length, nSectionAlignment));

	if(pssSegments[i].Length == 0)
	    DIE(("Virtual size of section %u is null\n", i));

	pssSegments[i].VirtualAddress = pishSectionHeaders[i].VirtualAddress;
	pssSegments[i].Characteristics = pishSectionHeaders[i].Characteristics;

	/* ensure the memory image is no larger than 4GB */
	if(!Intsafe_AddULong32(&nPrevVirtualEndOfSegment, pssSegments[i].VirtualAddress, pssSegments[i].Length))
	    DIE(("The image is larger than 4GB\n"));
    }

    /* spare our caller some work in validating the segments */
    *Flags = EXEFMT_LOAD_ASSUME_SEGMENTS_SORTED | EXEFMT_LOAD_ASSUME_SEGMENTS_NO_OVERLAP;

    if(nSectionAlignment >= PAGE_SIZE)
	*Flags |= EXEFMT_LOAD_ASSUME_SEGMENTS_PAGE_ALIGNED;

    /* Success */
    nStatus = STATUS_ROS_EXEFMT_LOADED_FORMAT | EXEFMT_LOADED_PE32;

l_Return:
    if(pBuffer)
	ExFreePool(pBuffer);

    return nStatus;
}

/* Note: Mmsp prefix denotes "Memory Manager Section Private". */

/*
 * FUNCTION:  Waits in kernel mode up to ten seconds for an MM_PAGEOP event.
 * ARGUMENTS: PMM_PAGEOP which event we should wait for.
 * RETURNS:   Status of the wait.
 */
static NTSTATUS
MmspWaitForPageOpCompletionEvent(PMM_PAGEOP PageOp)
{
   LARGE_INTEGER Timeout;
#ifdef __GNUC__ /* TODO: Use other macro to check for suffix to use? */

   Timeout.QuadPart = -100000000LL; // 10 sec
#else

   Timeout.QuadPart = -100000000; // 10 sec
#endif

   return KeWaitForSingleObject(&PageOp->CompletionEvent, 0, KernelMode, FALSE, &Timeout);
}


/*
 * FUNCTION:  Sets the page op completion event and releases the page op.
 * ARGUMENTS: PMM_PAGEOP.
 * RETURNS:   In shorter time than it takes you to even read this
 *            description, so don't even think about geting a mug of coffee.
 */
static void
MmspCompleteAndReleasePageOp(PMM_PAGEOP PageOp)
{
   KeSetEvent(&PageOp->CompletionEvent, IO_NO_INCREMENT, FALSE);
   MmReleasePageOp(PageOp);
}


/*
 * FUNCTION:  Waits in kernel mode indefinitely for a file object lock.
 * ARGUMENTS: PFILE_OBJECT to wait for.
 * RETURNS:   Status of the wait.
 */
static NTSTATUS
MmspWaitForFileLock(PFILE_OBJECT File)
{
    return STATUS_SUCCESS;
   //return KeWaitForSingleObject(&File->Lock, 0, KernelMode, FALSE, NULL);
}


VOID
MmFreePageTablesSectionSegment(PMM_SECTION_SEGMENT Segment)
{
   ULONG i;
   if (Segment->Length > NR_SECTION_PAGE_TABLES * PAGE_SIZE)
   {
      for (i = 0; i < NR_SECTION_PAGE_TABLES; i++)
      {
         if (Segment->PageDirectory.PageTables[i] != NULL)
         {
            ExFreePool(Segment->PageDirectory.PageTables[i]);
         }
      }
   }
}

VOID
NTAPI
MmFreeSectionSegments(PFILE_OBJECT FileObject)
{
   if (FileObject->SectionObjectPointer->ImageSectionObject != NULL)
   {
      PMM_IMAGE_SECTION_OBJECT ImageSectionObject;
      PMM_SECTION_SEGMENT SectionSegments;
      ULONG NrSegments;
      ULONG i;

      ImageSectionObject = (PMM_IMAGE_SECTION_OBJECT)FileObject->SectionObjectPointer->ImageSectionObject;
      NrSegments = ImageSectionObject->NrSegments;
      SectionSegments = ImageSectionObject->Segments;
      for (i = 0; i < NrSegments; i++)
      {
         if (SectionSegments[i].ReferenceCount != 0)
         {
            DPRINT1("Image segment %d still referenced (was %d)\n", i,
                    SectionSegments[i].ReferenceCount);
            KeBugCheck(MEMORY_MANAGEMENT);
         }
         MmFreePageTablesSectionSegment(&SectionSegments[i]);
      }
      ExFreePool(ImageSectionObject->Segments);
      ExFreePool(ImageSectionObject);
      FileObject->SectionObjectPointer->ImageSectionObject = NULL;
   }
   if (FileObject->SectionObjectPointer->DataSectionObject != NULL)
   {
      PMM_SECTION_SEGMENT Segment;

      Segment = (PMM_SECTION_SEGMENT)FileObject->SectionObjectPointer->
                DataSectionObject;

      if (Segment->ReferenceCount != 0)
      {
         DPRINT1("Data segment still referenced\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmFreePageTablesSectionSegment(Segment);
      ExFreePool(Segment);
      FileObject->SectionObjectPointer->DataSectionObject = NULL;
   }
}

VOID
NTAPI
MmLockSectionSegment(PMM_SECTION_SEGMENT Segment)
{
   ExAcquireFastMutex(&Segment->Lock);
}

VOID
NTAPI
MmUnlockSectionSegment(PMM_SECTION_SEGMENT Segment)
{
   ExReleaseFastMutex(&Segment->Lock);
}

VOID
NTAPI
MmSetPageEntrySectionSegment(PMM_SECTION_SEGMENT Segment,
                             ULONG Offset,
                             ULONG Entry)
{
   PSECTION_PAGE_TABLE Table;
   ULONG DirectoryOffset;
   ULONG TableOffset;

   if (Segment->Length <= NR_SECTION_PAGE_TABLES * PAGE_SIZE)
   {
      Table = (PSECTION_PAGE_TABLE)&Segment->PageDirectory;
   }
   else
   {
      DirectoryOffset = PAGE_TO_SECTION_PAGE_DIRECTORY_OFFSET(Offset);
      Table = Segment->PageDirectory.PageTables[DirectoryOffset];
      if (Table == NULL)
      {
         Table =
            Segment->PageDirectory.PageTables[DirectoryOffset] =
               ExAllocatePoolWithTag(NonPagedPool, sizeof(SECTION_PAGE_TABLE),
                                     TAG_SECTION_PAGE_TABLE);
         if (Table == NULL)
         {
            KeBugCheck(MEMORY_MANAGEMENT);
         }
         memset(Table, 0, sizeof(SECTION_PAGE_TABLE));
         DPRINT("Table %x\n", Table);
      }
   }
   TableOffset = PAGE_TO_SECTION_PAGE_TABLE_OFFSET(Offset);
   Table->Entry[TableOffset] = Entry;
}


ULONG
NTAPI
MmGetPageEntrySectionSegment(PMM_SECTION_SEGMENT Segment,
                             ULONG Offset)
{
   PSECTION_PAGE_TABLE Table;
   ULONG Entry;
   ULONG DirectoryOffset;
   ULONG TableOffset;

   DPRINT("MmGetPageEntrySection(Segment %x, Offset %x)\n", Segment, Offset);

   if (Segment->Length <= NR_SECTION_PAGE_TABLES * PAGE_SIZE)
   {
      Table = (PSECTION_PAGE_TABLE)&Segment->PageDirectory;
   }
   else
   {
      DirectoryOffset = PAGE_TO_SECTION_PAGE_DIRECTORY_OFFSET(Offset);
      Table = Segment->PageDirectory.PageTables[DirectoryOffset];
      DPRINT("Table %x\n", Table);
      if (Table == NULL)
      {
         return(0);
      }
   }
   TableOffset = PAGE_TO_SECTION_PAGE_TABLE_OFFSET(Offset);
   Entry = Table->Entry[TableOffset];
   return(Entry);
}

VOID
NTAPI
MmSharePageEntrySectionSegment(PMM_SECTION_SEGMENT Segment,
                               ULONG Offset)
{
   ULONG Entry;

   Entry = MmGetPageEntrySectionSegment(Segment, Offset);
   if (Entry == 0)
   {
      DPRINT1("Entry == 0 for MmSharePageEntrySectionSegment\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   if (SHARE_COUNT_FROM_SSE(Entry) == MAX_SHARE_COUNT)
   {
      DPRINT1("Maximum share count reached\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   if (IS_SWAP_FROM_SSE(Entry))
   {
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   Entry = MAKE_SSE(PAGE_FROM_SSE(Entry), SHARE_COUNT_FROM_SSE(Entry) + 1);
   MmSetPageEntrySectionSegment(Segment, Offset, Entry);
}

BOOLEAN
NTAPI
MmUnsharePageEntrySectionSegment(PROS_SECTION_OBJECT Section,
                                 PMM_SECTION_SEGMENT Segment,
                                 ULONG Offset,
                                 BOOLEAN Dirty,
                                 BOOLEAN PageOut)
{
   ULONG Entry;
   BOOLEAN IsDirectMapped = FALSE;

   Entry = MmGetPageEntrySectionSegment(Segment, Offset);
   if (Entry == 0)
   {
      DPRINT1("Entry == 0 for MmUnsharePageEntrySectionSegment\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   if (SHARE_COUNT_FROM_SSE(Entry) == 0)
   {
      DPRINT1("Zero share count for unshare\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   if (IS_SWAP_FROM_SSE(Entry))
   {
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   Entry = MAKE_SSE(PAGE_FROM_SSE(Entry), SHARE_COUNT_FROM_SSE(Entry) - 1);
   /*
    * If we reducing the share count of this entry to zero then set the entry
    * to zero and tell the cache the page is no longer mapped.
    */
   if (SHARE_COUNT_FROM_SSE(Entry) == 0)
   {
      PFILE_OBJECT FileObject;
      PBCB Bcb;
      SWAPENTRY SavedSwapEntry;
      PFN_NUMBER Page;
      BOOLEAN IsImageSection;
      ULONG FileOffset;

      FileOffset = Offset + Segment->FileOffset;

      IsImageSection = Section->AllocationAttributes & SEC_IMAGE ? TRUE : FALSE;

      Page = PFN_FROM_SSE(Entry);
      FileObject = Section->FileObject;
      if (FileObject != NULL &&
            !(Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
      {

         if ((FileOffset % PAGE_SIZE) == 0 &&
               (Offset + PAGE_SIZE <= Segment->RawLength || !IsImageSection))
         {
            NTSTATUS Status;
            Bcb = FileObject->SectionObjectPointer->SharedCacheMap;
            IsDirectMapped = TRUE;
            Status = CcRosUnmapCacheSegment(Bcb, FileOffset, Dirty);
            if (!NT_SUCCESS(Status))
            {
               DPRINT1("CcRosUnmapCacheSegment failed, status = %x\n", Status);
                KeBugCheck(MEMORY_MANAGEMENT);
            }
         }
      }

      SavedSwapEntry = MmGetSavedSwapEntryPage(Page);
      if (SavedSwapEntry == 0)
      {
         if (!PageOut &&
               ((Segment->Flags & MM_PAGEFILE_SEGMENT) ||
                (Segment->Characteristics & IMAGE_SCN_MEM_SHARED)))
         {
            /*
             * FIXME:
             *   Try to page out this page and set the swap entry
             *   within the section segment. There exist no rmap entry
             *   for this page. The pager thread can't page out a
             *   page without a rmap entry.
             */
            MmSetPageEntrySectionSegment(Segment, Offset, Entry);
         }
         else
         {
            MmSetPageEntrySectionSegment(Segment, Offset, 0);
            if (!IsDirectMapped)
            {
               MmReleasePageMemoryConsumer(MC_USER, Page);
            }
         }
      }
      else
      {
         if ((Segment->Flags & MM_PAGEFILE_SEGMENT) ||
               (Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
         {
            if (!PageOut)
            {
               if (Dirty)
               {
                  /*
                   * FIXME:
                   *   We hold all locks. Nobody can do something with the current
                   *   process and the current segment (also not within an other process).
                   */
                  NTSTATUS Status;
                  Status = MmWriteToSwapPage(SavedSwapEntry, Page);
                  if (!NT_SUCCESS(Status))
                  {
                     DPRINT1("MM: Failed to write to swap page (Status was 0x%.8X)\n", Status);
                      KeBugCheck(MEMORY_MANAGEMENT);
                  }
               }
               MmSetPageEntrySectionSegment(Segment, Offset, MAKE_SWAP_SSE(SavedSwapEntry));
               MmSetSavedSwapEntryPage(Page, 0);
            }
            MmReleasePageMemoryConsumer(MC_USER, Page);
         }
         else
         {
            DPRINT1("Found a swapentry for a non private page in an image or data file sgment\n");
            KeBugCheck(MEMORY_MANAGEMENT);
         }
      }
   }
   else
   {
      MmSetPageEntrySectionSegment(Segment, Offset, Entry);
   }
   return(SHARE_COUNT_FROM_SSE(Entry) > 0);
}

BOOLEAN MiIsPageFromCache(PMEMORY_AREA MemoryArea,
                       ULONG SegOffset)
{
   if (!(MemoryArea->Data.SectionData.Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
   {
      PBCB Bcb;
      PCACHE_SEGMENT CacheSeg;
      Bcb = MemoryArea->Data.SectionData.Section->FileObject->SectionObjectPointer->SharedCacheMap;
      CacheSeg = CcRosLookupCacheSegment(Bcb, SegOffset + MemoryArea->Data.SectionData.Segment->FileOffset);
      if (CacheSeg)
      {
         CcRosReleaseCacheSegment(Bcb, CacheSeg, CacheSeg->Valid, FALSE, TRUE);
         return TRUE;
      }
   }
   return FALSE;
}

NTSTATUS
NTAPI
MiCopyFromUserPage(PFN_NUMBER DestPage, PVOID SourceAddress)
{
    PEPROCESS Process;
    KIRQL Irql;
    PVOID TempAddress;
    
    Process = PsGetCurrentProcess();
    TempAddress = MiMapPageInHyperSpace(Process, DestPage, &Irql);
    if (TempAddress == NULL)
    {
        return(STATUS_NO_MEMORY);
    }
    memcpy(TempAddress, SourceAddress, PAGE_SIZE);
    MiUnmapPageInHyperSpace(Process, TempAddress, Irql);
    return(STATUS_SUCCESS);
}

NTSTATUS
NTAPI
MiReadPage(PMEMORY_AREA MemoryArea,
           ULONG SegOffset,
           PPFN_NUMBER Page)
/*
 * FUNCTION: Read a page for a section backed memory area.
 * PARAMETERS:
 *       MemoryArea - Memory area to read the page for.
 *       Offset - Offset of the page to read.
 *       Page - Variable that receives a page contains the read data.
 */
{
   ULONG BaseOffset;
   ULONG FileOffset;
   PVOID BaseAddress;
   BOOLEAN UptoDate;
   PCACHE_SEGMENT CacheSeg;
   PFILE_OBJECT FileObject;
   NTSTATUS Status;
   ULONG RawLength;
   PBCB Bcb;
   BOOLEAN IsImageSection;
   ULONG Length;

   FileObject = MemoryArea->Data.SectionData.Section->FileObject;
   Bcb = FileObject->SectionObjectPointer->SharedCacheMap;
   RawLength = MemoryArea->Data.SectionData.Segment->RawLength;
   FileOffset = SegOffset + MemoryArea->Data.SectionData.Segment->FileOffset;
   IsImageSection = MemoryArea->Data.SectionData.Section->AllocationAttributes & SEC_IMAGE ? TRUE : FALSE;

   ASSERT(Bcb);

   DPRINT("%S %x\n", FileObject->FileName.Buffer, FileOffset);

   /*
    * If the file system is letting us go directly to the cache and the
    * memory area was mapped at an offset in the file which is page aligned
    * then get the related cache segment.
    */
   if ((FileOffset % PAGE_SIZE) == 0 &&
       (SegOffset + PAGE_SIZE <= RawLength || !IsImageSection) &&
       !(MemoryArea->Data.SectionData.Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
   {

      /*
       * Get the related cache segment; we use a lower level interface than
       * filesystems do because it is safe for us to use an offset with a
       * alignment less than the file system block size.
       */
      Status = CcRosGetCacheSegment(Bcb,
                                    FileOffset,
                                    &BaseOffset,
                                    &BaseAddress,
                                    &UptoDate,
                                    &CacheSeg);
      if (!NT_SUCCESS(Status))
      {
         return(Status);
      }
      if (!UptoDate)
      {
         /*
          * If the cache segment isn't up to date then call the file
          * system to read in the data.
          */
         Status = ReadCacheSegment(CacheSeg);
         if (!NT_SUCCESS(Status))
         {
            CcRosReleaseCacheSegment(Bcb, CacheSeg, FALSE, FALSE, FALSE);
            return Status;
         }
      }
      /*
       * Retrieve the page from the cache segment that we actually want.
       */
      (*Page) = MmGetPhysicalAddress((char*)BaseAddress +
                                     FileOffset - BaseOffset).LowPart >> PAGE_SHIFT;

      CcRosReleaseCacheSegment(Bcb, CacheSeg, TRUE, FALSE, TRUE);
   }
   else
   {
      PEPROCESS Process;
      KIRQL Irql;
      PVOID PageAddr;
      ULONG CacheSegOffset;

      /*
       * Allocate a page, this is rather complicated by the possibility
       * we might have to move other things out of memory
       */
      Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, Page);
      if (!NT_SUCCESS(Status))
      {
         return(Status);
      }
      Status = CcRosGetCacheSegment(Bcb,
                                    FileOffset,
                                    &BaseOffset,
                                    &BaseAddress,
                                    &UptoDate,
                                    &CacheSeg);
      if (!NT_SUCCESS(Status))
      {
         return(Status);
      }
      if (!UptoDate)
      {
         /*
          * If the cache segment isn't up to date then call the file
          * system to read in the data.
          */
         Status = ReadCacheSegment(CacheSeg);
         if (!NT_SUCCESS(Status))
         {
            CcRosReleaseCacheSegment(Bcb, CacheSeg, FALSE, FALSE, FALSE);
            return Status;
         }
      }

      Process = PsGetCurrentProcess();
      PageAddr = MiMapPageInHyperSpace(Process, *Page, &Irql);
      CacheSegOffset = BaseOffset + CacheSeg->Bcb->CacheSegmentSize - FileOffset;
      Length = RawLength - SegOffset;
      if (Length <= CacheSegOffset && Length <= PAGE_SIZE)
      {
         memcpy(PageAddr, (char*)BaseAddress + FileOffset - BaseOffset, Length);
      }
      else if (CacheSegOffset >= PAGE_SIZE)
      {
         memcpy(PageAddr, (char*)BaseAddress + FileOffset - BaseOffset, PAGE_SIZE);
      }
      else
      {
         memcpy(PageAddr, (char*)BaseAddress + FileOffset - BaseOffset, CacheSegOffset);
         MiUnmapPageInHyperSpace(Process, PageAddr, Irql);
         CcRosReleaseCacheSegment(Bcb, CacheSeg, TRUE, FALSE, FALSE);
         Status = CcRosGetCacheSegment(Bcb,
                                       FileOffset + CacheSegOffset,
                                       &BaseOffset,
                                       &BaseAddress,
                                       &UptoDate,
                                       &CacheSeg);
         if (!NT_SUCCESS(Status))
         {
            return(Status);
         }
         if (!UptoDate)
         {
            /*
             * If the cache segment isn't up to date then call the file
             * system to read in the data.
             */
            Status = ReadCacheSegment(CacheSeg);
            if (!NT_SUCCESS(Status))
            {
               CcRosReleaseCacheSegment(Bcb, CacheSeg, FALSE, FALSE, FALSE);
               return Status;
            }
         }
         PageAddr = MiMapPageInHyperSpace(Process, *Page, &Irql);
         if (Length < PAGE_SIZE)
         {
            memcpy((char*)PageAddr + CacheSegOffset, BaseAddress, Length - CacheSegOffset);
         }
         else
         {
            memcpy((char*)PageAddr + CacheSegOffset, BaseAddress, PAGE_SIZE - CacheSegOffset);
         }
      }
      MiUnmapPageInHyperSpace(Process, PageAddr, Irql);
      CcRosReleaseCacheSegment(Bcb, CacheSeg, TRUE, FALSE, FALSE);
   }
   return(STATUS_SUCCESS);
}

NTSTATUS
NTAPI
MmNotPresentFaultSectionView(PMMSUPPORT AddressSpace,
                             MEMORY_AREA* MemoryArea,
                             PVOID Address,
                             BOOLEAN Locked)
{
   ULONG Offset;
   PFN_NUMBER Page;
   NTSTATUS Status;
   PVOID PAddress;
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;
   ULONG Entry;
   ULONG Entry1;
   ULONG Attributes;
   PMM_PAGEOP PageOp;
   PMM_REGION Region;
   BOOLEAN HasSwapEntry;
   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
    
   /*
    * There is a window between taking the page fault and locking the
    * address space when another thread could load the page so we check
    * that.
    */
   if (MmIsPagePresent(Process, Address))
   {
      return(STATUS_SUCCESS);
   }

   PAddress = MM_ROUND_DOWN(Address, PAGE_SIZE);
   Offset = (ULONG_PTR)PAddress - (ULONG_PTR)MemoryArea->StartingAddress
            + MemoryArea->Data.SectionData.ViewOffset;

   Segment = MemoryArea->Data.SectionData.Segment;
   Section = MemoryArea->Data.SectionData.Section;
   Region = MmFindRegion(MemoryArea->StartingAddress,
                         &MemoryArea->Data.SectionData.RegionListHead,
                         Address, NULL);
   /*
    * Lock the segment
    */
   MmLockSectionSegment(Segment);

   /*
    * Check if this page needs to be mapped COW
    */
   if ((Segment->WriteCopy) &&
       (Region->Protect == PAGE_READWRITE ||
       Region->Protect == PAGE_EXECUTE_READWRITE))
   {
      Attributes = Region->Protect == PAGE_READWRITE ? PAGE_READONLY : PAGE_EXECUTE_READ;
   }
   else
   {
      Attributes = Region->Protect;
   }

   /*
    * Get or create a page operation descriptor
    */
   PageOp = MmGetPageOp(MemoryArea, NULL, 0, Segment, Offset, MM_PAGEOP_PAGEIN, FALSE);
   if (PageOp == NULL)
   {
      DPRINT1("MmGetPageOp failed\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }

   /*
    * Check if someone else is already handling this fault, if so wait
    * for them
    */
   if (PageOp->Thread != PsGetCurrentThread())
   {
      MmUnlockSectionSegment(Segment);
      MmUnlockAddressSpace(AddressSpace);
      Status = MmspWaitForPageOpCompletionEvent(PageOp);
      /*
       * Check for various strange conditions
       */
      if (Status != STATUS_SUCCESS)
      {
         DPRINT1("Failed to wait for page op, status = %x\n", Status);
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      if (PageOp->Status == STATUS_PENDING)
      {
         DPRINT1("Woke for page op before completion\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmLockAddressSpace(AddressSpace);
      /*
       * If this wasn't a pagein then restart the operation
       */
      if (PageOp->OpType != MM_PAGEOP_PAGEIN)
      {
         MmspCompleteAndReleasePageOp(PageOp);
         DPRINT("Address 0x%.8X\n", Address);
         return(STATUS_MM_RESTART_OPERATION);
      }

      /*
      * If the thread handling this fault has failed then we don't retry
      */
      if (!NT_SUCCESS(PageOp->Status))
      {
         Status = PageOp->Status;
         MmspCompleteAndReleasePageOp(PageOp);
         DPRINT("Address 0x%.8X\n", Address);
         return(Status);
      }
      MmLockSectionSegment(Segment);
      /*
       * If the completed fault was for another address space then set the
       * page in this one.
       */
      if (!MmIsPagePresent(Process, Address))
      {
         Entry = MmGetPageEntrySectionSegment(Segment, Offset);
         HasSwapEntry = MmIsPageSwapEntry(Process, (PVOID)PAddress);

         if (PAGE_FROM_SSE(Entry) == 0 || HasSwapEntry)
         {
            /*
             * The page was a private page in another or in our address space
             */
            MmUnlockSectionSegment(Segment);
            MmspCompleteAndReleasePageOp(PageOp);
            return(STATUS_MM_RESTART_OPERATION);
         }

         Page = PFN_FROM_SSE(Entry);

         MmSharePageEntrySectionSegment(Segment, Offset);

         /* FIXME: Should we call MmCreateVirtualMappingUnsafe if
          * (Section->AllocationAttributes & SEC_PHYSICALMEMORY) is true?
          */
         Status = MmCreateVirtualMapping(Process,
                                         Address,
                                         Attributes,
                                         &Page,
                                         1);
         if (!NT_SUCCESS(Status))
         {
            DPRINT1("Unable to create virtual mapping\n");
            KeBugCheck(MEMORY_MANAGEMENT);
         }
         MmInsertRmap(Page, Process, (PVOID)PAddress);
      }
      MmUnlockSectionSegment(Segment);
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }

   HasSwapEntry = MmIsPageSwapEntry(Process, (PVOID)PAddress);
   if (HasSwapEntry)
   {
      /*
       * Must be private page we have swapped out.
       */
      SWAPENTRY SwapEntry;

      /*
       * Sanity check
       */
      if (Segment->Flags & MM_PAGEFILE_SEGMENT)
      {
         DPRINT1("Found a swaped out private page in a pagefile section.\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }

      MmUnlockSectionSegment(Segment);
      MmDeletePageFileMapping(Process, (PVOID)PAddress, &SwapEntry);

      MmUnlockAddressSpace(AddressSpace);
      Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, &Page);
      if (!NT_SUCCESS(Status))
      {
          KeBugCheck(MEMORY_MANAGEMENT);
      }

      Status = MmReadFromSwapPage(SwapEntry, Page);
      if (!NT_SUCCESS(Status))
      {
         DPRINT1("MmReadFromSwapPage failed, status = %x\n", Status);
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmLockAddressSpace(AddressSpace);
      Status = MmCreateVirtualMapping(Process,
                                      Address,
                                      Region->Protect,
                                      &Page,
                                      1);
      if (!NT_SUCCESS(Status))
      {
         DPRINT("MmCreateVirtualMapping failed, not out of memory\n");
          KeBugCheck(MEMORY_MANAGEMENT);
         return(Status);
      }

      /*
       * Store the swap entry for later use.
       */
      MmSetSavedSwapEntryPage(Page, SwapEntry);

      /*
       * Add the page to the process's working set
       */
      MmInsertRmap(Page, Process, (PVOID)PAddress);

      /*
       * Finish the operation
       */
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }

   /*
    * Satisfying a page fault on a map of /Device/PhysicalMemory is easy
    */
   if (Section->AllocationAttributes & SEC_PHYSICALMEMORY)
   {
      MmUnlockSectionSegment(Segment);
      /*
       * Just map the desired physical page
       */
      Page = Offset >> PAGE_SHIFT;
      Status = MmCreateVirtualMappingUnsafe(Process,
                                            Address,
                                            Region->Protect,
                                            &Page,
                                            1);
      if (!NT_SUCCESS(Status))
      {
         DPRINT("MmCreateVirtualMappingUnsafe failed, not out of memory\n");
          KeBugCheck(MEMORY_MANAGEMENT);
         return(Status);
      }

      /*
       * Cleanup and release locks
       */
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }

   /*
    * Map anonymous memory for BSS sections
    */
   if (Segment->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA)
   {
      MmUnlockSectionSegment(Segment);
      Status = MmRequestPageMemoryConsumer(MC_USER, FALSE, &Page);
      if (!NT_SUCCESS(Status))
      {
         MmUnlockAddressSpace(AddressSpace);
         Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, &Page);
         MmLockAddressSpace(AddressSpace);
      }
      if (!NT_SUCCESS(Status))
      {
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      Status = MmCreateVirtualMapping(Process,
                                      Address,
                                      Region->Protect,
                                      &Page,
                                      1);
      if (!NT_SUCCESS(Status))
      {
         DPRINT("MmCreateVirtualMapping failed, not out of memory\n");
          KeBugCheck(MEMORY_MANAGEMENT);
         return(Status);
      }
      MmInsertRmap(Page, Process, (PVOID)PAddress);

      /*
       * Cleanup and release locks
       */
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }

   /*
    * Get the entry corresponding to the offset within the section
    */
   Entry = MmGetPageEntrySectionSegment(Segment, Offset);

   if (Entry == 0)
   {
      /*
       * If the entry is zero (and it can't change because we have
       * locked the segment) then we need to load the page.
       */

      /*
       * Release all our locks and read in the page from disk
       */
      MmUnlockSectionSegment(Segment);
      MmUnlockAddressSpace(AddressSpace);

      if ((Segment->Flags & MM_PAGEFILE_SEGMENT) ||
          (Offset >= PAGE_ROUND_UP(Segment->RawLength) && Section->AllocationAttributes & SEC_IMAGE))
      {
         Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, &Page);
         if (!NT_SUCCESS(Status))
         {
            DPRINT1("MmRequestPageMemoryConsumer failed (Status %x)\n", Status);
         }
      }
      else
      {
         Status = MiReadPage(MemoryArea, Offset, &Page);
         if (!NT_SUCCESS(Status))
         {
            DPRINT1("MiReadPage failed (Status %x)\n", Status);
         }
      }
      if (!NT_SUCCESS(Status))
      {
         /*
          * FIXME: What do we know in this case?
          */
         /*
          * Cleanup and release locks
          */
         MmLockAddressSpace(AddressSpace);
         PageOp->Status = Status;
         MmspCompleteAndReleasePageOp(PageOp);
         DPRINT("Address 0x%.8X\n", Address);
         return(Status);
      }
      /*
       * Relock the address space and segment
       */
      MmLockAddressSpace(AddressSpace);
      MmLockSectionSegment(Segment);

      /*
       * Check the entry. No one should change the status of a page
       * that has a pending page-in.
       */
      Entry1 = MmGetPageEntrySectionSegment(Segment, Offset);
      if (Entry != Entry1)
      {
         DPRINT1("Someone changed ppte entry while we slept\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }

      /*
       * Mark the offset within the section as having valid, in-memory
       * data
       */
      Entry = MAKE_SSE(Page << PAGE_SHIFT, 1);
      MmSetPageEntrySectionSegment(Segment, Offset, Entry);
      MmUnlockSectionSegment(Segment);

      Status = MmCreateVirtualMapping(Process,
                                      Address,
                                      Attributes,
                                      &Page,
                                      1);
      if (!NT_SUCCESS(Status))
      {
         DPRINT1("Unable to create virtual mapping\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmInsertRmap(Page, Process, (PVOID)PAddress);

      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }
   else if (IS_SWAP_FROM_SSE(Entry))
   {
      SWAPENTRY SwapEntry;

      SwapEntry = SWAPENTRY_FROM_SSE(Entry);

      /*
      * Release all our locks and read in the page from disk
      */
      MmUnlockSectionSegment(Segment);

      MmUnlockAddressSpace(AddressSpace);

      Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, &Page);
      if (!NT_SUCCESS(Status))
      {
          KeBugCheck(MEMORY_MANAGEMENT);
      }

      Status = MmReadFromSwapPage(SwapEntry, Page);
      if (!NT_SUCCESS(Status))
      {
          KeBugCheck(MEMORY_MANAGEMENT);
      }

      /*
       * Relock the address space and segment
       */
      MmLockAddressSpace(AddressSpace);
      MmLockSectionSegment(Segment);

      /*
       * Check the entry. No one should change the status of a page
       * that has a pending page-in.
       */
      Entry1 = MmGetPageEntrySectionSegment(Segment, Offset);
      if (Entry != Entry1)
      {
         DPRINT1("Someone changed ppte entry while we slept\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }

      /*
       * Mark the offset within the section as having valid, in-memory
       * data
       */
      Entry = MAKE_SSE(Page << PAGE_SHIFT, 1);
      MmSetPageEntrySectionSegment(Segment, Offset, Entry);
      MmUnlockSectionSegment(Segment);

      /*
       * Save the swap entry.
       */
      MmSetSavedSwapEntryPage(Page, SwapEntry);
      Status = MmCreateVirtualMapping(Process,
                                      Address,
                                      Region->Protect,
                                      &Page,
                                      1);
      if (!NT_SUCCESS(Status))
      {
         DPRINT1("Unable to create virtual mapping\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmInsertRmap(Page, Process, (PVOID)PAddress);
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }
   else
   {
      /*
       * If the section offset is already in-memory and valid then just
       * take another reference to the page
       */

      Page = PFN_FROM_SSE(Entry);

      MmSharePageEntrySectionSegment(Segment, Offset);
      MmUnlockSectionSegment(Segment);

      Status = MmCreateVirtualMapping(Process,
                                      Address,
                                      Attributes,
                                      &Page,
                                      1);
      if (!NT_SUCCESS(Status))
      {
         DPRINT1("Unable to create virtual mapping\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmInsertRmap(Page, Process, (PVOID)PAddress);
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }
}

NTSTATUS
NTAPI
MmAccessFaultSectionView(PMMSUPPORT AddressSpace,
                         MEMORY_AREA* MemoryArea,
                         PVOID Address,
                         BOOLEAN Locked)
{
   PMM_SECTION_SEGMENT Segment;
   PROS_SECTION_OBJECT Section;
   PFN_NUMBER OldPage;
   PFN_NUMBER NewPage;
   NTSTATUS Status;
   PVOID PAddress;
   ULONG Offset;
   PMM_PAGEOP PageOp;
   PMM_REGION Region;
   ULONG Entry;
   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
    
   DPRINT("MmAccessFaultSectionView(%x, %x, %x, %x)\n", AddressSpace, MemoryArea, Address, Locked);

   /*
    * Check if the page has been paged out or has already been set readwrite
    */
   if (!MmIsPagePresent(Process, Address) ||
         MmGetPageProtect(Process, Address) & PAGE_READWRITE)
   {
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_SUCCESS);
   }

   /*
    * Find the offset of the page
    */
   PAddress = MM_ROUND_DOWN(Address, PAGE_SIZE);
   Offset = (ULONG_PTR)PAddress - (ULONG_PTR)MemoryArea->StartingAddress
            + MemoryArea->Data.SectionData.ViewOffset;

   Segment = MemoryArea->Data.SectionData.Segment;
   Section = MemoryArea->Data.SectionData.Section;
   Region = MmFindRegion(MemoryArea->StartingAddress,
                         &MemoryArea->Data.SectionData.RegionListHead,
                         Address, NULL);
   /*
    * Lock the segment
    */
   MmLockSectionSegment(Segment);

   OldPage = MmGetPfnForProcess(NULL, Address);
   Entry = MmGetPageEntrySectionSegment(Segment, Offset);

   MmUnlockSectionSegment(Segment);

   /*
    * Check if we are doing COW
    */
   if (!((Segment->WriteCopy) &&
         (Region->Protect == PAGE_READWRITE ||
          Region->Protect == PAGE_EXECUTE_READWRITE)))
   {
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_ACCESS_VIOLATION);
   }

   if (IS_SWAP_FROM_SSE(Entry) ||
       PFN_FROM_SSE(Entry) != OldPage)
   {
      /* This is a private page. We must only change the page protection. */
      MmSetPageProtect(Process, PAddress, Region->Protect);
      return(STATUS_SUCCESS);
   }

   /*
    * Get or create a pageop
    */
   PageOp = MmGetPageOp(MemoryArea, NULL, 0, Segment, Offset,
                        MM_PAGEOP_ACCESSFAULT, FALSE);
   if (PageOp == NULL)
   {
      DPRINT1("MmGetPageOp failed\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }

   /*
    * Wait for any other operations to complete
    */
   if (PageOp->Thread != PsGetCurrentThread())
   {
      MmUnlockAddressSpace(AddressSpace);
      Status = MmspWaitForPageOpCompletionEvent(PageOp);
      /*
      * Check for various strange conditions
      */
      if (Status == STATUS_TIMEOUT)
      {
         DPRINT1("Failed to wait for page op, status = %x\n", Status);
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      if (PageOp->Status == STATUS_PENDING)
      {
         DPRINT1("Woke for page op before completion\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      /*
      * Restart the operation
      */
      MmLockAddressSpace(AddressSpace);
      MmspCompleteAndReleasePageOp(PageOp);
      DPRINT("Address 0x%.8X\n", Address);
      return(STATUS_MM_RESTART_OPERATION);
   }

   /*
    * Release locks now we have the pageop
    */
   MmUnlockAddressSpace(AddressSpace);

   /*
    * Allocate a page
    */
   Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, &NewPage);
   if (!NT_SUCCESS(Status))
   {
       KeBugCheck(MEMORY_MANAGEMENT);
   }

   /*
    * Copy the old page
    */
   MiCopyFromUserPage(NewPage, PAddress);

   MmLockAddressSpace(AddressSpace);
   /*
    * Delete the old entry.
    */
   MmDeleteVirtualMapping(Process, Address, FALSE, NULL, NULL);

   /*
    * Set the PTE to point to the new page
    */
   Status = MmCreateVirtualMapping(Process,
                                   Address,
                                   Region->Protect,
                                   &NewPage,
                                   1);
   if (!NT_SUCCESS(Status))
   {
      DPRINT("MmCreateVirtualMapping failed, not out of memory\n");
       KeBugCheck(MEMORY_MANAGEMENT);
      return(Status);
   }
   if (!NT_SUCCESS(Status))
   {
      DPRINT1("Unable to create virtual mapping\n");
       KeBugCheck(MEMORY_MANAGEMENT);
   }

   /*
    * Unshare the old page.
    */
   MmDeleteRmap(OldPage, Process, PAddress);
   MmInsertRmap(NewPage, Process, PAddress);
   MmLockSectionSegment(Segment);
   MmUnsharePageEntrySectionSegment(Section, Segment, Offset, FALSE, FALSE);
   MmUnlockSectionSegment(Segment);

   PageOp->Status = STATUS_SUCCESS;
   MmspCompleteAndReleasePageOp(PageOp);
   DPRINT("Address 0x%.8X\n", Address);
   return(STATUS_SUCCESS);
}

VOID
MmPageOutDeleteMapping(PVOID Context, PEPROCESS Process, PVOID Address)
{
   MM_SECTION_PAGEOUT_CONTEXT* PageOutContext;
   BOOLEAN WasDirty;
   PFN_NUMBER Page;

   PageOutContext = (MM_SECTION_PAGEOUT_CONTEXT*)Context;
   if (Process)
   {
      MmLockAddressSpace(&Process->Vm);
   }

   MmDeleteVirtualMapping(Process,
                          Address,
                          FALSE,
                          &WasDirty,
                          &Page);
   if (WasDirty)
   {
      PageOutContext->WasDirty = TRUE;
   }
   if (!PageOutContext->Private)
   {
      MmLockSectionSegment(PageOutContext->Segment);
      MmUnsharePageEntrySectionSegment((PROS_SECTION_OBJECT)PageOutContext->Section,
                                       PageOutContext->Segment,
                                       PageOutContext->Offset,
                                       PageOutContext->WasDirty,
                                       TRUE);
      MmUnlockSectionSegment(PageOutContext->Segment);
   }
   if (Process)
   {
      MmUnlockAddressSpace(&Process->Vm);
   }

   if (PageOutContext->Private)
   {
      MmReleasePageMemoryConsumer(MC_USER, Page);
   }

   DPRINT("PhysicalAddress %x, Address %x\n", Page << PAGE_SHIFT, Address);
}

NTSTATUS
NTAPI
MmPageOutSectionView(PMMSUPPORT AddressSpace,
                     MEMORY_AREA* MemoryArea,
                     PVOID Address,
                     PMM_PAGEOP PageOp)
{
   PFN_NUMBER Page;
   MM_SECTION_PAGEOUT_CONTEXT Context;
   SWAPENTRY SwapEntry;
   ULONG Entry;
   ULONG FileOffset;
   NTSTATUS Status;
   PFILE_OBJECT FileObject;
   PBCB Bcb = NULL;
   BOOLEAN DirectMapped;
   BOOLEAN IsImageSection;
   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
   KIRQL OldIrql;
    
   Address = (PVOID)PAGE_ROUND_DOWN(Address);

   /*
    * Get the segment and section.
    */
   Context.Segment = MemoryArea->Data.SectionData.Segment;
   Context.Section = MemoryArea->Data.SectionData.Section;

   Context.Offset = (ULONG_PTR)Address - (ULONG_PTR)MemoryArea->StartingAddress
                    + MemoryArea->Data.SectionData.ViewOffset;
   FileOffset = Context.Offset + Context.Segment->FileOffset;

   IsImageSection = Context.Section->AllocationAttributes & SEC_IMAGE ? TRUE : FALSE;

   FileObject = Context.Section->FileObject;
   DirectMapped = FALSE;
   if (FileObject != NULL &&
       !(Context.Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
   {
      Bcb = FileObject->SectionObjectPointer->SharedCacheMap;

      /*
       * If the file system is letting us go directly to the cache and the
       * memory area was mapped at an offset in the file which is page aligned
       * then note this is a direct mapped page.
       */
      if ((FileOffset % PAGE_SIZE) == 0 &&
            (Context.Offset + PAGE_SIZE <= Context.Segment->RawLength || !IsImageSection))
      {
         DirectMapped = TRUE;
      }
   }


   /*
    * This should never happen since mappings of physical memory are never
    * placed in the rmap lists.
    */
   if (Context.Section->AllocationAttributes & SEC_PHYSICALMEMORY)
   {
      DPRINT1("Trying to page out from physical memory section address 0x%X "
              "process %d\n", Address,
              Process ? Process->UniqueProcessId : 0);
       KeBugCheck(MEMORY_MANAGEMENT);
   }

   /*
    * Get the section segment entry and the physical address.
    */
   Entry = MmGetPageEntrySectionSegment(Context.Segment, Context.Offset);
   if (!MmIsPagePresent(Process, Address))
   {
      DPRINT1("Trying to page out not-present page at (%d,0x%.8X).\n",
              Process ? Process->UniqueProcessId : 0, Address);
       KeBugCheck(MEMORY_MANAGEMENT);
   }
   Page = MmGetPfnForProcess(Process, Address);
   SwapEntry = MmGetSavedSwapEntryPage(Page);

   /*
    * Prepare the context structure for the rmap delete call.
    */
   Context.WasDirty = FALSE;
   if (Context.Segment->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA ||
         IS_SWAP_FROM_SSE(Entry) ||
         PFN_FROM_SSE(Entry) != Page)
   {
      Context.Private = TRUE;
   }
   else
   {
      Context.Private = FALSE;
   }

   /*
    * Take an additional reference to the page or the cache segment.
    */
   if (DirectMapped && !Context.Private)
   {
      if(!MiIsPageFromCache(MemoryArea, Context.Offset))
      {
         DPRINT1("Direct mapped non private page is not associated with the cache.\n");
          KeBugCheck(MEMORY_MANAGEMENT);
      }
   }
   else
   {
      OldIrql = KeAcquireQueuedSpinLock(LockQueuePfnLock);
      MmReferencePage(Page);
      KeReleaseQueuedSpinLock(LockQueuePfnLock, OldIrql);
   }

   MmDeleteAllRmaps(Page, (PVOID)&Context, MmPageOutDeleteMapping);

   /*
    * If this wasn't a private page then we should have reduced the entry to
    * zero by deleting all the rmaps.
    */
   if (!Context.Private && MmGetPageEntrySectionSegment(Context.Segment, Context.Offset) != 0)
   {
      if (!(Context.Segment->Flags & MM_PAGEFILE_SEGMENT) &&
            !(Context.Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
      {
          KeBugCheck(MEMORY_MANAGEMENT);
      }
   }

   /*
    * If the page wasn't dirty then we can just free it as for a readonly page.
    * Since we unmapped all the mappings above we know it will not suddenly
    * become dirty.
    * If the page is from a pagefile section and has no swap entry,
    * we can't free the page at this point.
    */
   SwapEntry = MmGetSavedSwapEntryPage(Page);
   if (Context.Segment->Flags & MM_PAGEFILE_SEGMENT)
   {
      if (Context.Private)
      {
         DPRINT1("Found a %s private page (address %x) in a pagefile segment.\n",
                 Context.WasDirty ? "dirty" : "clean", Address);
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      if (!Context.WasDirty && SwapEntry != 0)
      {
         MmSetSavedSwapEntryPage(Page, 0);
         MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, MAKE_SWAP_SSE(SwapEntry));
         MmReleasePageMemoryConsumer(MC_USER, Page);
         PageOp->Status = STATUS_SUCCESS;
         MmspCompleteAndReleasePageOp(PageOp);
         return(STATUS_SUCCESS);
      }
   }
   else if (Context.Segment->Characteristics & IMAGE_SCN_MEM_SHARED)
   {
      if (Context.Private)
      {
         DPRINT1("Found a %s private page (address %x) in a shared section segment.\n",
                 Context.WasDirty ? "dirty" : "clean", Address);
          KeBugCheck(MEMORY_MANAGEMENT);
      }
      if (!Context.WasDirty || SwapEntry != 0)
      {
         MmSetSavedSwapEntryPage(Page, 0);
         if (SwapEntry != 0)
         {
            MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, MAKE_SWAP_SSE(SwapEntry));
         }
         MmReleasePageMemoryConsumer(MC_USER, Page);
         PageOp->Status = STATUS_SUCCESS;
         MmspCompleteAndReleasePageOp(PageOp);
         return(STATUS_SUCCESS);
      }
   }
   else if (!Context.Private && DirectMapped)
   {
      if (SwapEntry != 0)
      {
         DPRINT1("Found a swapentry for a non private and direct mapped page (address %x)\n",
                 Address);
         KeBugCheck(MEMORY_MANAGEMENT);
      }
      Status = CcRosUnmapCacheSegment(Bcb, FileOffset, FALSE);
      if (!NT_SUCCESS(Status))
      {
         DPRINT1("CCRosUnmapCacheSegment failed, status = %x\n", Status);
         KeBugCheck(MEMORY_MANAGEMENT);
      }
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      return(STATUS_SUCCESS);
   }
   else if (!Context.WasDirty && !DirectMapped && !Context.Private)
   {
      if (SwapEntry != 0)
      {
         DPRINT1("Found a swap entry for a non dirty, non private and not direct mapped page (address %x)\n",
                 Address);
         KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmReleasePageMemoryConsumer(MC_USER, Page);
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      return(STATUS_SUCCESS);
   }
   else if (!Context.WasDirty && Context.Private && SwapEntry != 0)
   {
      MmSetSavedSwapEntryPage(Page, 0);
      MmLockAddressSpace(AddressSpace);
      Status = MmCreatePageFileMapping(Process,
                                       Address,
                                       SwapEntry);
      MmUnlockAddressSpace(AddressSpace);
      if (!NT_SUCCESS(Status))
      {
         KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmReleasePageMemoryConsumer(MC_USER, Page);
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      return(STATUS_SUCCESS);
   }

   /*
    * If necessary, allocate an entry in the paging file for this page
    */
   if (SwapEntry == 0)
   {
      SwapEntry = MmAllocSwapPage();
      if (SwapEntry == 0)
      {
         MmShowOutOfSpaceMessagePagingFile();
         MmLockAddressSpace(AddressSpace);
         /*
          * For private pages restore the old mappings.
          */
         if (Context.Private)
         {
            Status = MmCreateVirtualMapping(Process,
                                            Address,
                                            MemoryArea->Protect,
                                            &Page,
                                            1);
            MmSetDirtyPage(Process, Address);
            MmInsertRmap(Page,
                         Process,
                         Address);
         }
         else
         {
            /*
             * For non-private pages if the page wasn't direct mapped then
             * set it back into the section segment entry so we don't loose
             * our copy. Otherwise it will be handled by the cache manager.
             */
            Status = MmCreateVirtualMapping(Process,
                                            Address,
                                            MemoryArea->Protect,
                                            &Page,
                                            1);
            MmSetDirtyPage(Process, Address);
            MmInsertRmap(Page,
                         Process,
                         Address);
            Entry = MAKE_SSE(Page << PAGE_SHIFT, 1);
            MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, Entry);
         }
         MmUnlockAddressSpace(AddressSpace);
         PageOp->Status = STATUS_UNSUCCESSFUL;
         MmspCompleteAndReleasePageOp(PageOp);
         return(STATUS_PAGEFILE_QUOTA);
      }
   }

   /*
    * Write the page to the pagefile
    */
   Status = MmWriteToSwapPage(SwapEntry, Page);
   if (!NT_SUCCESS(Status))
   {
      DPRINT1("MM: Failed to write to swap page (Status was 0x%.8X)\n",
              Status);
      /*
       * As above: undo our actions.
       * FIXME: Also free the swap page.
       */
      MmLockAddressSpace(AddressSpace);
      if (Context.Private)
      {
         Status = MmCreateVirtualMapping(Process,
                                         Address,
                                         MemoryArea->Protect,
                                         &Page,
                                         1);
         MmSetDirtyPage(Process, Address);
         MmInsertRmap(Page,
                      Process,
                      Address);
      }
      else
      {
         Status = MmCreateVirtualMapping(Process,
                                         Address,
                                         MemoryArea->Protect,
                                         &Page,
                                         1);
         MmSetDirtyPage(Process, Address);
         MmInsertRmap(Page,
                      Process,
                      Address);
         Entry = MAKE_SSE(Page << PAGE_SHIFT, 1);
         MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, Entry);
      }
      MmUnlockAddressSpace(AddressSpace);
      PageOp->Status = STATUS_UNSUCCESSFUL;
      MmspCompleteAndReleasePageOp(PageOp);
      return(STATUS_UNSUCCESSFUL);
   }

   /*
    * Otherwise we have succeeded.
    */
   DPRINT("MM: Wrote section page 0x%.8X to swap!\n", Page << PAGE_SHIFT);
   MmSetSavedSwapEntryPage(Page, 0);
   if (Context.Segment->Flags & MM_PAGEFILE_SEGMENT ||
         Context.Segment->Characteristics & IMAGE_SCN_MEM_SHARED)
   {
      MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, MAKE_SWAP_SSE(SwapEntry));
   }
   else
   {
      MmReleasePageMemoryConsumer(MC_USER, Page);
   }

   if (Context.Private)
   {
      MmLockAddressSpace(AddressSpace);
      Status = MmCreatePageFileMapping(Process,
                                       Address,
                                       SwapEntry);
      MmUnlockAddressSpace(AddressSpace);
      if (!NT_SUCCESS(Status))
      {
         KeBugCheck(MEMORY_MANAGEMENT);
      }
   }
   else
   {
      Entry = MAKE_SWAP_SSE(SwapEntry);
      MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, Entry);
   }

   PageOp->Status = STATUS_SUCCESS;
   MmspCompleteAndReleasePageOp(PageOp);
   return(STATUS_SUCCESS);
}

NTSTATUS
NTAPI
MmWritePageSectionView(PMMSUPPORT AddressSpace,
                       PMEMORY_AREA MemoryArea,
                       PVOID Address,
                       PMM_PAGEOP PageOp)
{
   ULONG Offset;
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;
   PFN_NUMBER Page;
   SWAPENTRY SwapEntry;
   ULONG Entry;
   BOOLEAN Private;
   NTSTATUS Status;
   PFILE_OBJECT FileObject;
   PBCB Bcb = NULL;
   BOOLEAN DirectMapped;
   BOOLEAN IsImageSection;
   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);

   Address = (PVOID)PAGE_ROUND_DOWN(Address);

   Offset = (ULONG_PTR)Address - (ULONG_PTR)MemoryArea->StartingAddress
            + MemoryArea->Data.SectionData.ViewOffset;

   /*
    * Get the segment and section.
    */
   Segment = MemoryArea->Data.SectionData.Segment;
   Section = MemoryArea->Data.SectionData.Section;
   IsImageSection = Section->AllocationAttributes & SEC_IMAGE ? TRUE : FALSE;

   FileObject = Section->FileObject;
   DirectMapped = FALSE;
   if (FileObject != NULL &&
         !(Segment->Characteristics & IMAGE_SCN_MEM_SHARED))
   {
      Bcb = FileObject->SectionObjectPointer->SharedCacheMap;

      /*
       * If the file system is letting us go directly to the cache and the
       * memory area was mapped at an offset in the file which is page aligned
       * then note this is a direct mapped page.
       */
      if (((Offset + Segment->FileOffset) % PAGE_SIZE) == 0 &&
            (Offset + PAGE_SIZE <= Segment->RawLength || !IsImageSection))
      {
         DirectMapped = TRUE;
      }
   }

   /*
    * This should never happen since mappings of physical memory are never
    * placed in the rmap lists.
    */
   if (Section->AllocationAttributes & SEC_PHYSICALMEMORY)
   {
      DPRINT1("Trying to write back page from physical memory mapped at %X "
              "process %d\n", Address,
              Process ? Process->UniqueProcessId : 0);
      KeBugCheck(MEMORY_MANAGEMENT);
   }

   /*
    * Get the section segment entry and the physical address.
    */
   Entry = MmGetPageEntrySectionSegment(Segment, Offset);
   if (!MmIsPagePresent(Process, Address))
   {
      DPRINT1("Trying to page out not-present page at (%d,0x%.8X).\n",
              Process ? Process->UniqueProcessId : 0, Address);
      KeBugCheck(MEMORY_MANAGEMENT);
   }
   Page = MmGetPfnForProcess(Process, Address);
   SwapEntry = MmGetSavedSwapEntryPage(Page);

   /*
    * Check for a private (COWed) page.
    */
   if (Segment->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA ||
         IS_SWAP_FROM_SSE(Entry) ||
         PFN_FROM_SSE(Entry) != Page)
   {
      Private = TRUE;
   }
   else
   {
      Private = FALSE;
   }

   /*
    * Speculatively set all mappings of the page to clean.
    */
   MmSetCleanAllRmaps(Page);

   /*
    * If this page was direct mapped from the cache then the cache manager
    * will take care of writing it back to disk.
    */
   if (DirectMapped && !Private)
   {
      ASSERT(SwapEntry == 0);
      CcRosMarkDirtyCacheSegment(Bcb, Offset + Segment->FileOffset);
      PageOp->Status = STATUS_SUCCESS;
      MmspCompleteAndReleasePageOp(PageOp);
      return(STATUS_SUCCESS);
   }

   /*
    * If necessary, allocate an entry in the paging file for this page
    */
   if (SwapEntry == 0)
   {
      SwapEntry = MmAllocSwapPage();
      if (SwapEntry == 0)
      {
         MmSetDirtyAllRmaps(Page);
         PageOp->Status = STATUS_UNSUCCESSFUL;
         MmspCompleteAndReleasePageOp(PageOp);
         return(STATUS_PAGEFILE_QUOTA);
      }
      MmSetSavedSwapEntryPage(Page, SwapEntry);
   }

   /*
    * Write the page to the pagefile
    */
   Status = MmWriteToSwapPage(SwapEntry, Page);
   if (!NT_SUCCESS(Status))
   {
      DPRINT1("MM: Failed to write to swap page (Status was 0x%.8X)\n",
              Status);
      MmSetDirtyAllRmaps(Page);
      PageOp->Status = STATUS_UNSUCCESSFUL;
      MmspCompleteAndReleasePageOp(PageOp);
      return(STATUS_UNSUCCESSFUL);
   }

   /*
    * Otherwise we have succeeded.
    */
   DPRINT("MM: Wrote section page 0x%.8X to swap!\n", Page << PAGE_SHIFT);
   PageOp->Status = STATUS_SUCCESS;
   MmspCompleteAndReleasePageOp(PageOp);
   return(STATUS_SUCCESS);
}

static VOID
MmAlterViewAttributes(PMMSUPPORT AddressSpace,
                      PVOID BaseAddress,
                      ULONG RegionSize,
                      ULONG OldType,
                      ULONG OldProtect,
                      ULONG NewType,
                      ULONG NewProtect)
{
   PMEMORY_AREA MemoryArea;
   PMM_SECTION_SEGMENT Segment;
   BOOLEAN DoCOW = FALSE;
   ULONG i;
   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);

   MemoryArea = MmLocateMemoryAreaByAddress(AddressSpace, BaseAddress);
   Segment = MemoryArea->Data.SectionData.Segment;

   if ((Segment->WriteCopy) &&
         (NewProtect == PAGE_READWRITE || NewProtect == PAGE_EXECUTE_READWRITE))
   {
      DoCOW = TRUE;
   }

   if (OldProtect != NewProtect)
   {
      for (i = 0; i < PAGE_ROUND_UP(RegionSize) / PAGE_SIZE; i++)
      {
         PVOID Address = (char*)BaseAddress + (i * PAGE_SIZE);
         ULONG Protect = NewProtect;

         /*
          * If we doing COW for this segment then check if the page is
          * already private.
          */
         if (DoCOW && MmIsPagePresent(Process, Address))
         {
            ULONG Offset;
            ULONG Entry;
            PFN_NUMBER Page;

            Offset = (ULONG_PTR)Address - (ULONG_PTR)MemoryArea->StartingAddress
                     + MemoryArea->Data.SectionData.ViewOffset;
            Entry = MmGetPageEntrySectionSegment(Segment, Offset);
            Page = MmGetPfnForProcess(Process, Address);

            Protect = PAGE_READONLY;
            if (Segment->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA ||
                  IS_SWAP_FROM_SSE(Entry) ||
                  PFN_FROM_SSE(Entry) != Page)
            {
               Protect = NewProtect;
            }
         }

         if (MmIsPagePresent(Process, Address))
         {
            MmSetPageProtect(Process, Address,
                             Protect);
         }
      }
   }
}

NTSTATUS
NTAPI
MmProtectSectionView(PMMSUPPORT AddressSpace,
                     PMEMORY_AREA MemoryArea,
                     PVOID BaseAddress,
                     ULONG Length,
                     ULONG Protect,
                     PULONG OldProtect)
{
   PMM_REGION Region;
   NTSTATUS Status;
   ULONG_PTR MaxLength;

   MaxLength = (ULONG_PTR)MemoryArea->EndingAddress - (ULONG_PTR)BaseAddress;
   if (Length > MaxLength)
      Length = MaxLength;

   Region = MmFindRegion(MemoryArea->StartingAddress,
                         &MemoryArea->Data.SectionData.RegionListHead,
                         BaseAddress, NULL);
   if ((MemoryArea->Flags & SEC_NO_CHANGE) &&
       Region->Protect != Protect)
   {
      return STATUS_INVALID_PAGE_PROTECTION;
   }

   *OldProtect = Region->Protect;
   Status = MmAlterRegion(AddressSpace, MemoryArea->StartingAddress,
                          &MemoryArea->Data.SectionData.RegionListHead,
                          BaseAddress, Length, Region->Type, Protect,
                          MmAlterViewAttributes);

   return(Status);
}

NTSTATUS NTAPI
MmQuerySectionView(PMEMORY_AREA MemoryArea,
                   PVOID Address,
                   PMEMORY_BASIC_INFORMATION Info,
                   PSIZE_T ResultLength)
{
   PMM_REGION Region;
   PVOID RegionBaseAddress;
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;

   Region = MmFindRegion((PVOID)MemoryArea->StartingAddress,
                         &MemoryArea->Data.SectionData.RegionListHead,
                         Address, &RegionBaseAddress);
   if (Region == NULL)
   {
      return STATUS_UNSUCCESSFUL;
   }

   Section = MemoryArea->Data.SectionData.Section;
   if (Section->AllocationAttributes & SEC_IMAGE)
   {
      Segment = MemoryArea->Data.SectionData.Segment;
      Info->AllocationBase = (PUCHAR)MemoryArea->StartingAddress - Segment->VirtualAddress;
      Info->Type = MEM_IMAGE;
   }
   else
   {
      Info->AllocationBase = MemoryArea->StartingAddress;
      Info->Type = MEM_MAPPED;
   }
   Info->BaseAddress = RegionBaseAddress;
   Info->AllocationProtect = MemoryArea->Protect;
   Info->RegionSize = Region->Length;
   Info->State = MEM_COMMIT;
   Info->Protect = Region->Protect;

   *ResultLength = sizeof(MEMORY_BASIC_INFORMATION);
   return(STATUS_SUCCESS);
}

VOID
NTAPI
MmpFreePageFileSegment(PMM_SECTION_SEGMENT Segment)
{
   ULONG Length;
   ULONG Offset;
   ULONG Entry;
   ULONG SavedSwapEntry;
   PFN_NUMBER Page;

   Page = 0;

   Length = PAGE_ROUND_UP(Segment->Length);
   for (Offset = 0; Offset < Length; Offset += PAGE_SIZE)
   {
      Entry = MmGetPageEntrySectionSegment(Segment, Offset);
      if (Entry)
      {
         if (IS_SWAP_FROM_SSE(Entry))
         {
            MmFreeSwapPage(SWAPENTRY_FROM_SSE(Entry));
         }
         else
         {
            Page = PFN_FROM_SSE(Entry);
            SavedSwapEntry = MmGetSavedSwapEntryPage(Page);
            if (SavedSwapEntry != 0)
            {
               MmSetSavedSwapEntryPage(Page, 0);
               MmFreeSwapPage(SavedSwapEntry);
            }
            MmReleasePageMemoryConsumer(MC_USER, Page);
         }
         MmSetPageEntrySectionSegment(Segment, Offset, 0);
      }
   }
}

VOID NTAPI
MmpDeleteSection(PVOID ObjectBody)
{
   PROS_SECTION_OBJECT Section = (PROS_SECTION_OBJECT)ObjectBody;

   DPRINT("MmpDeleteSection(ObjectBody %x)\n", ObjectBody);
   if (Section->AllocationAttributes & SEC_IMAGE)
   {
      ULONG i;
      ULONG NrSegments;
      ULONG RefCount;
      PMM_SECTION_SEGMENT SectionSegments;

      /*
       * NOTE: Section->ImageSection can be NULL for short time
       * during the section creating. If we fail for some reason
       * until the image section is properly initialized we shouldn't
       * process further here.
       */
      if (Section->ImageSection == NULL)
         return;

      SectionSegments = Section->ImageSection->Segments;
      NrSegments = Section->ImageSection->NrSegments;

      for (i = 0; i < NrSegments; i++)
      {
         if (SectionSegments[i].Characteristics & IMAGE_SCN_MEM_SHARED)
         {
            MmLockSectionSegment(&SectionSegments[i]);
         }
         RefCount = InterlockedDecrementUL(&SectionSegments[i].ReferenceCount);
         if (SectionSegments[i].Characteristics & IMAGE_SCN_MEM_SHARED)
         {
            if (RefCount == 0)
            {
               MmpFreePageFileSegment(&SectionSegments[i]);
            }
            MmUnlockSectionSegment(&SectionSegments[i]);
         }
      }
   }
   else
   {
      /*
       * NOTE: Section->Segment can be NULL for short time
       * during the section creating.
       */
      if (Section->Segment == NULL)
         return;

      if (Section->Segment->Flags & MM_PAGEFILE_SEGMENT)
      {
         MmpFreePageFileSegment(Section->Segment);
         MmFreePageTablesSectionSegment(Section->Segment);
         ExFreePool(Section->Segment);
         Section->Segment = NULL;
      }
      else
      {
         (void)InterlockedDecrementUL(&Section->Segment->ReferenceCount);
      }
   }
   if (Section->FileObject != NULL)
   {
      CcRosDereferenceCache(Section->FileObject);
      ObDereferenceObject(Section->FileObject);
      Section->FileObject = NULL;
   }
}

VOID NTAPI
MmpCloseSection(IN PEPROCESS Process OPTIONAL,
                IN PVOID Object,
                IN ACCESS_MASK GrantedAccess,
                IN ULONG ProcessHandleCount,
                IN ULONG SystemHandleCount)
{
   DPRINT("MmpCloseSection(OB %x, HC %d)\n",
          Object, ProcessHandleCount);
}

NTSTATUS
INIT_FUNCTION
NTAPI
MmCreatePhysicalMemorySection(VOID)
{
   PROS_SECTION_OBJECT PhysSection;
   NTSTATUS Status;
   OBJECT_ATTRIBUTES Obj;
   UNICODE_STRING Name = RTL_CONSTANT_STRING(L"\\Device\\PhysicalMemory");
   LARGE_INTEGER SectionSize;
   HANDLE Handle;

   /*
    * Create the section mapping physical memory
    */
   SectionSize.QuadPart = 0xFFFFFFFF;
   InitializeObjectAttributes(&Obj,
                              &Name,
                              OBJ_PERMANENT,
                              NULL,
                              NULL);
   Status = MmCreateSection((PVOID)&PhysSection,
                            SECTION_ALL_ACCESS,
                            &Obj,
                            &SectionSize,
                            PAGE_EXECUTE_READWRITE,
                            0,
                            NULL,
                            NULL);
   if (!NT_SUCCESS(Status))
   {
      DPRINT1("Failed to create PhysicalMemory section\n");
      KeBugCheck(MEMORY_MANAGEMENT);
   }
   Status = ObInsertObject(PhysSection,
                           NULL,
                           SECTION_ALL_ACCESS,
                           0,
                           NULL,
                           &Handle);
   if (!NT_SUCCESS(Status))
   {
      ObDereferenceObject(PhysSection);
   }
   ObCloseHandle(Handle, KernelMode);
   PhysSection->AllocationAttributes |= SEC_PHYSICALMEMORY;
   PhysSection->Segment->Flags &= ~MM_PAGEFILE_SEGMENT;

   return(STATUS_SUCCESS);
}

NTSTATUS
INIT_FUNCTION
NTAPI
MmInitSectionImplementation(VOID)
{
   OBJECT_TYPE_INITIALIZER ObjectTypeInitializer;
   UNICODE_STRING Name;

   DPRINT("Creating Section Object Type\n");

   /* Initialize the Section object type  */
   RtlZeroMemory(&ObjectTypeInitializer, sizeof(ObjectTypeInitializer));
   RtlInitUnicodeString(&Name, L"Section");
   ObjectTypeInitializer.Length = sizeof(ObjectTypeInitializer);
   ObjectTypeInitializer.DefaultPagedPoolCharge = sizeof(ROS_SECTION_OBJECT);
   ObjectTypeInitializer.PoolType = PagedPool;
   ObjectTypeInitializer.UseDefaultObject = TRUE;
   ObjectTypeInitializer.GenericMapping = MmpSectionMapping;
   ObjectTypeInitializer.DeleteProcedure = MmpDeleteSection;
   ObjectTypeInitializer.CloseProcedure = MmpCloseSection;
   ObjectTypeInitializer.ValidAccessMask = SECTION_ALL_ACCESS;
   ObCreateObjectType(&Name, &ObjectTypeInitializer, NULL, &MmSectionObjectType);
    
   MmCreatePhysicalMemorySection();

   return(STATUS_SUCCESS);
}

NTSTATUS
NTAPI
MmCreatePageFileSection(PROS_SECTION_OBJECT *SectionObject,
                        ACCESS_MASK DesiredAccess,
                        POBJECT_ATTRIBUTES ObjectAttributes,
                        PLARGE_INTEGER UMaximumSize,
                        ULONG SectionPageProtection,
                        ULONG AllocationAttributes)
/*
 * Create a section which is backed by the pagefile
 */
{
   LARGE_INTEGER MaximumSize;
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;
   NTSTATUS Status;

   if (UMaximumSize == NULL)
   {
      return(STATUS_UNSUCCESSFUL);
   }
   MaximumSize = *UMaximumSize;

   /*
    * Create the section
    */
   Status = ObCreateObject(ExGetPreviousMode(),
                           MmSectionObjectType,
                           ObjectAttributes,
                           ExGetPreviousMode(),
                           NULL,
                           sizeof(ROS_SECTION_OBJECT),
                           0,
                           0,
                           (PVOID*)(PVOID)&Section);
   if (!NT_SUCCESS(Status))
   {
      return(Status);
   }

   /*
    * Initialize it
    */
   RtlZeroMemory(Section, sizeof(ROS_SECTION_OBJECT));
   Section->SectionPageProtection = SectionPageProtection;
   Section->AllocationAttributes = AllocationAttributes;
   Section->MaximumSize = MaximumSize;
   Segment = ExAllocatePoolWithTag(NonPagedPool, sizeof(MM_SECTION_SEGMENT),
                                   TAG_MM_SECTION_SEGMENT);
   if (Segment == NULL)
   {
      ObDereferenceObject(Section);
      return(STATUS_NO_MEMORY);
   }
   Section->Segment = Segment;
   Segment->ReferenceCount = 1;
   ExInitializeFastMutex(&Segment->Lock);
   Segment->FileOffset = 0;
   Segment->Protection = SectionPageProtection;
   Segment->RawLength = MaximumSize.u.LowPart;
   Segment->Length = PAGE_ROUND_UP(MaximumSize.u.LowPart);
   Segment->Flags = MM_PAGEFILE_SEGMENT;
   Segment->WriteCopy = FALSE;
   RtlZeroMemory(&Segment->PageDirectory, sizeof(SECTION_PAGE_DIRECTORY));
   Segment->VirtualAddress = 0;
   Segment->Characteristics = 0;
   *SectionObject = Section;
   return(STATUS_SUCCESS);
}


NTSTATUS
NTAPI
MmCreateDataFileSection(PROS_SECTION_OBJECT *SectionObject,
                        ACCESS_MASK DesiredAccess,
                        POBJECT_ATTRIBUTES ObjectAttributes,
                        PLARGE_INTEGER UMaximumSize,
                        ULONG SectionPageProtection,
                        ULONG AllocationAttributes,
                        HANDLE FileHandle)
/*
 * Create a section backed by a data file
 */
{
   PROS_SECTION_OBJECT Section;
   NTSTATUS Status;
   LARGE_INTEGER MaximumSize;
   PFILE_OBJECT FileObject;
   PMM_SECTION_SEGMENT Segment;
   ULONG FileAccess;
   IO_STATUS_BLOCK Iosb;
   LARGE_INTEGER Offset;
   CHAR Buffer;
   FILE_STANDARD_INFORMATION FileInfo;
   ULONG Length;

   /*
    * Create the section
    */
   Status = ObCreateObject(ExGetPreviousMode(),
                           MmSectionObjectType,
                           ObjectAttributes,
                           ExGetPreviousMode(),
                           NULL,
                           sizeof(ROS_SECTION_OBJECT),
                           0,
                           0,
                           (PVOID*)(PVOID)&Section);
   if (!NT_SUCCESS(Status))
   {
      return(Status);
   }
   /*
    * Initialize it
    */
   RtlZeroMemory(Section, sizeof(ROS_SECTION_OBJECT));
   Section->SectionPageProtection = SectionPageProtection;
   Section->AllocationAttributes = AllocationAttributes;

   /*
    * Check file access required
    */
   if (SectionPageProtection & PAGE_READWRITE ||
         SectionPageProtection & PAGE_EXECUTE_READWRITE)
   {
      FileAccess = FILE_READ_DATA | FILE_WRITE_DATA;
   }
   else
   {
      FileAccess = FILE_READ_DATA;
   }

   /*
    * Reference the file handle
    */
   Status = ObReferenceObjectByHandle(FileHandle,
                                      FileAccess,
                                      IoFileObjectType,
                                      ExGetPreviousMode(),
                                      (PVOID*)(PVOID)&FileObject,
                                      NULL);
   if (!NT_SUCCESS(Status))
   {
      ObDereferenceObject(Section);
      return(Status);
   }

   /*
    * FIXME: This is propably not entirely correct. We can't look into
    * the standard FCB header because it might not be initialized yet
    * (as in case of the EXT2FS driver by Manoj Paul Joseph where the
    * standard file information is filled on first request).
    */
   Status = IoQueryFileInformation(FileObject,
                                   FileStandardInformation,
                                   sizeof(FILE_STANDARD_INFORMATION),
                                   &FileInfo,
                                   &Length);
   Iosb.Information = Length;
   if (!NT_SUCCESS(Status))
   {
      ObDereferenceObject(Section);
      ObDereferenceObject(FileObject);
      return Status;
   }

   /*
    * FIXME: Revise this once a locking order for file size changes is
    * decided
    */
   if ((UMaximumSize != NULL) && (UMaximumSize->QuadPart != 0))
   {
         MaximumSize = *UMaximumSize;
   }
   else
   {
      MaximumSize = FileInfo.EndOfFile;
      /* Mapping zero-sized files isn't allowed. */
      if (MaximumSize.QuadPart == 0)
      {
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return STATUS_FILE_INVALID;
      }
   }

   if (MaximumSize.QuadPart > FileInfo.EndOfFile.QuadPart)
   {
      Status = IoSetInformation(FileObject,
                                FileAllocationInformation,
                                sizeof(LARGE_INTEGER),
                                &MaximumSize);
      if (!NT_SUCCESS(Status))
      {
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return(STATUS_SECTION_NOT_EXTENDED);
      }
   }

   if (FileObject->SectionObjectPointer == NULL ||
         FileObject->SectionObjectPointer->SharedCacheMap == NULL)
   {
      /*
       * Read a bit so caching is initiated for the file object.
       * This is only needed because MiReadPage currently cannot
       * handle non-cached streams.
       */
      Offset.QuadPart = 0;
      Status = ZwReadFile(FileHandle,
                          NULL,
                          NULL,
                          NULL,
                          &Iosb,
                          &Buffer,
                          sizeof (Buffer),
                          &Offset,
                          0);
      if (!NT_SUCCESS(Status) && (Status != STATUS_END_OF_FILE))
      {
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return(Status);
      }
      if (FileObject->SectionObjectPointer == NULL ||
            FileObject->SectionObjectPointer->SharedCacheMap == NULL)
      {
         /* FIXME: handle this situation */
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return STATUS_INVALID_PARAMETER;
      }
   }

   /*
    * Lock the file
    */
   Status = MmspWaitForFileLock(FileObject);
   if (Status != STATUS_SUCCESS)
   {
      ObDereferenceObject(Section);
      ObDereferenceObject(FileObject);
      return(Status);
   }

   /*
    * If this file hasn't been mapped as a data file before then allocate a
    * section segment to describe the data file mapping
    */
   if (FileObject->SectionObjectPointer->DataSectionObject == NULL)
   {
      Segment = ExAllocatePoolWithTag(NonPagedPool, sizeof(MM_SECTION_SEGMENT),
                                      TAG_MM_SECTION_SEGMENT);
      if (Segment == NULL)
      {
         //KeSetEvent((PVOID)&FileObject->Lock, IO_NO_INCREMENT, FALSE);
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return(STATUS_NO_MEMORY);
      }
      Section->Segment = Segment;
      Segment->ReferenceCount = 1;
      ExInitializeFastMutex(&Segment->Lock);
      /*
       * Set the lock before assigning the segment to the file object
       */
      ExAcquireFastMutex(&Segment->Lock);
      FileObject->SectionObjectPointer->DataSectionObject = (PVOID)Segment;

      Segment->FileOffset = 0;
      Segment->Protection = SectionPageProtection;
      Segment->Flags = MM_DATAFILE_SEGMENT;
      Segment->Characteristics = 0;
      Segment->WriteCopy = FALSE;
      if (AllocationAttributes & SEC_RESERVE)
      {
         Segment->Length = Segment->RawLength = 0;
      }
      else
      {
         Segment->RawLength = MaximumSize.u.LowPart;
         Segment->Length = PAGE_ROUND_UP(Segment->RawLength);
      }
      Segment->VirtualAddress = 0;
      RtlZeroMemory(&Segment->PageDirectory, sizeof(SECTION_PAGE_DIRECTORY));
   }
   else
   {
      /*
       * If the file is already mapped as a data file then we may need
       * to extend it
       */
      Segment =
         (PMM_SECTION_SEGMENT)FileObject->SectionObjectPointer->
         DataSectionObject;
      Section->Segment = Segment;
      (void)InterlockedIncrementUL(&Segment->ReferenceCount);
      MmLockSectionSegment(Segment);

      if (MaximumSize.u.LowPart > Segment->RawLength &&
            !(AllocationAttributes & SEC_RESERVE))
      {
         Segment->RawLength = MaximumSize.u.LowPart;
         Segment->Length = PAGE_ROUND_UP(Segment->RawLength);
      }
   }
   MmUnlockSectionSegment(Segment);
   Section->FileObject = FileObject;
   Section->MaximumSize = MaximumSize;
   CcRosReferenceCache(FileObject);
   //KeSetEvent((PVOID)&FileObject->Lock, IO_NO_INCREMENT, FALSE);
   *SectionObject = Section;
   return(STATUS_SUCCESS);
}

/*
 TODO: not that great (declaring loaders statically, having to declare all of
 them, having to keep them extern, etc.), will fix in the future
*/
extern NTSTATUS NTAPI PeFmtCreateSection
(
 IN CONST VOID * FileHeader,
 IN SIZE_T FileHeaderSize,
 IN PVOID File,
 OUT PMM_IMAGE_SECTION_OBJECT ImageSectionObject,
 OUT PULONG Flags,
 IN PEXEFMT_CB_READ_FILE ReadFileCb,
 IN PEXEFMT_CB_ALLOCATE_SEGMENTS AllocateSegmentsCb
);

extern NTSTATUS NTAPI ElfFmtCreateSection
(
 IN CONST VOID * FileHeader,
 IN SIZE_T FileHeaderSize,
 IN PVOID File,
 OUT PMM_IMAGE_SECTION_OBJECT ImageSectionObject,
 OUT PULONG Flags,
 IN PEXEFMT_CB_READ_FILE ReadFileCb,
 IN PEXEFMT_CB_ALLOCATE_SEGMENTS AllocateSegmentsCb
);

/* TODO: this is a standard DDK/PSDK macro */
#ifndef RTL_NUMBER_OF
#define RTL_NUMBER_OF(ARR_) (sizeof(ARR_) / sizeof((ARR_)[0]))
#endif

static PEXEFMT_LOADER ExeFmtpLoaders[] =
{
 PeFmtCreateSection,
#ifdef __ELF
 ElfFmtCreateSection
#endif
};

static
PMM_SECTION_SEGMENT
NTAPI
ExeFmtpAllocateSegments(IN ULONG NrSegments)
{
 SIZE_T SizeOfSegments;
 PMM_SECTION_SEGMENT Segments;

 /* TODO: check for integer overflow */
 SizeOfSegments = sizeof(MM_SECTION_SEGMENT) * NrSegments;

 Segments = ExAllocatePoolWithTag(NonPagedPool,
                                  SizeOfSegments,
                                  TAG_MM_SECTION_SEGMENT);

 if(Segments)
  RtlZeroMemory(Segments, SizeOfSegments);

 return Segments;
}

static
NTSTATUS
NTAPI
ExeFmtpReadFile(IN PVOID File,
                IN PLARGE_INTEGER Offset,
                IN ULONG Length,
                OUT PVOID * Data,
                OUT PVOID * AllocBase,
                OUT PULONG ReadSize)
{
   NTSTATUS Status;
   LARGE_INTEGER FileOffset;
   ULONG AdjustOffset;
   ULONG OffsetAdjustment;
   ULONG BufferSize;
   ULONG UsedSize;
   PVOID Buffer;

   ASSERT_IRQL_LESS(DISPATCH_LEVEL);

   if(Length == 0)
   {
      KeBugCheck(MEMORY_MANAGEMENT);
   }

   FileOffset = *Offset;

   /* Negative/special offset: it cannot be used in this context */
   if(FileOffset.u.HighPart < 0)
   {
      KeBugCheck(MEMORY_MANAGEMENT);
   }

   AdjustOffset = PAGE_ROUND_DOWN(FileOffset.u.LowPart);
   OffsetAdjustment = FileOffset.u.LowPart - AdjustOffset;
   FileOffset.u.LowPart = AdjustOffset;

   BufferSize = Length + OffsetAdjustment;
   BufferSize = PAGE_ROUND_UP(BufferSize);

   /*
    * It's ok to use paged pool, because this is a temporary buffer only used in
    * the loading of executables. The assumption is that MmCreateSection is
    * always called at low IRQLs and that these buffers don't survive a brief
    * initialization phase
    */
   Buffer = ExAllocatePoolWithTag(PagedPool,
                                  BufferSize,
                                  'rXmM');
   if (!Buffer)
   {
      KeBugCheck(MEMORY_MANAGEMENT);
   }

   UsedSize = 0;

#if 0
   Status = MmspPageRead(File,
                         Buffer,
                         BufferSize,
                         &FileOffset,
                         &UsedSize);
#else
/*
 * FIXME: if we don't use ZwReadFile, caching is not enabled for the file and
 * nothing will work. But using ZwReadFile is wrong, and using its side effects
 * to initialize internal state is even worse. Our cache manager is in need of
 * professional help
 */
   {
      IO_STATUS_BLOCK Iosb;

      Status = ZwReadFile(File,
                          NULL,
                          NULL,
                          NULL,
                          &Iosb,
                          Buffer,
                          BufferSize,
                          &FileOffset,
                          NULL);

      if(NT_SUCCESS(Status))
      {
         UsedSize = Iosb.Information;
      }
   }
#endif

   if(NT_SUCCESS(Status) && UsedSize < OffsetAdjustment)
   {
      Status = STATUS_IN_PAGE_ERROR;
      ASSERT(!NT_SUCCESS(Status));
   }

   if(NT_SUCCESS(Status))
   {
      *Data = (PVOID)((ULONG_PTR)Buffer + OffsetAdjustment);
      *AllocBase = Buffer;
      *ReadSize = UsedSize - OffsetAdjustment;
   }
   else
   {
      ExFreePoolWithTag(Buffer, 'rXmM');
   }

   return Status;
}

#ifdef NASSERT
# define MmspAssertSegmentsSorted(OBJ_) ((void)0)
# define MmspAssertSegmentsNoOverlap(OBJ_) ((void)0)
# define MmspAssertSegmentsPageAligned(OBJ_) ((void)0)
#else
static
VOID
NTAPI
MmspAssertSegmentsSorted(IN PMM_IMAGE_SECTION_OBJECT ImageSectionObject)
{
   ULONG i;

   for( i = 1; i < ImageSectionObject->NrSegments; ++ i )
   {
      ASSERT(ImageSectionObject->Segments[i].VirtualAddress >=
             ImageSectionObject->Segments[i - 1].VirtualAddress);
   }
}

static
VOID
NTAPI
MmspAssertSegmentsNoOverlap(IN PMM_IMAGE_SECTION_OBJECT ImageSectionObject)
{
   ULONG i;

   MmspAssertSegmentsSorted(ImageSectionObject);

   for( i = 0; i < ImageSectionObject->NrSegments; ++ i )
   {
      ASSERT(ImageSectionObject->Segments[i].Length > 0);

      if(i > 0)
      {
         ASSERT(ImageSectionObject->Segments[i].VirtualAddress >=
                (ImageSectionObject->Segments[i - 1].VirtualAddress +
                 ImageSectionObject->Segments[i - 1].Length));
      }
   }
}

static
VOID
NTAPI
MmspAssertSegmentsPageAligned(IN PMM_IMAGE_SECTION_OBJECT ImageSectionObject)
{
   ULONG i;

   for( i = 0; i < ImageSectionObject->NrSegments; ++ i )
   {
      ASSERT((ImageSectionObject->Segments[i].VirtualAddress % PAGE_SIZE) == 0);
      ASSERT((ImageSectionObject->Segments[i].Length % PAGE_SIZE) == 0);
   }
}
#endif

static
int
__cdecl
MmspCompareSegments(const void * x,
                    const void * y)
{
   const MM_SECTION_SEGMENT *Segment1 = (const MM_SECTION_SEGMENT *)x;
   const MM_SECTION_SEGMENT *Segment2 = (const MM_SECTION_SEGMENT *)y;

   return
      (Segment1->VirtualAddress - Segment2->VirtualAddress) >>
      ((sizeof(ULONG_PTR) - sizeof(int)) * 8);
}

/*
 * Ensures an image section's segments are sorted in memory
 */
static
VOID
NTAPI
MmspSortSegments(IN OUT PMM_IMAGE_SECTION_OBJECT ImageSectionObject,
                 IN ULONG Flags)
{
   if (Flags & EXEFMT_LOAD_ASSUME_SEGMENTS_SORTED)
   {
      MmspAssertSegmentsSorted(ImageSectionObject);
   }
   else
   {
      qsort(ImageSectionObject->Segments,
            ImageSectionObject->NrSegments,
            sizeof(ImageSectionObject->Segments[0]),
            MmspCompareSegments);
   }
}


/*
 * Ensures an image section's segments don't overlap in memory and don't have
 * gaps and don't have a null size. We let them map to overlapping file regions,
 * though - that's not necessarily an error
 */
static
BOOLEAN
NTAPI
MmspCheckSegmentBounds
(
 IN OUT PMM_IMAGE_SECTION_OBJECT ImageSectionObject,
 IN ULONG Flags
)
{
   ULONG i;

   if (Flags & EXEFMT_LOAD_ASSUME_SEGMENTS_NO_OVERLAP)
   {
      MmspAssertSegmentsNoOverlap(ImageSectionObject);
      return TRUE;
   }

   ASSERT(ImageSectionObject->NrSegments >= 1);

   for ( i = 0; i < ImageSectionObject->NrSegments; ++ i )
   {
      if(ImageSectionObject->Segments[i].Length == 0)
      {
         return FALSE;
      }

      if(i > 0)
      {
         /*
          * TODO: relax the limitation on gaps. For example, gaps smaller than a
          * page could be OK (Windows seems to be OK with them), and larger gaps
          * could lead to image sections spanning several discontiguous regions
          * (NtMapViewOfSection could then refuse to map them, and they could
          * e.g. only be allowed as parameters to NtCreateProcess, like on UNIX)
          */
         if ((ImageSectionObject->Segments[i - 1].VirtualAddress +
              ImageSectionObject->Segments[i - 1].Length) !=
              ImageSectionObject->Segments[i].VirtualAddress)
         {
            return FALSE;
         }
      }
   }

   return TRUE;
}

/*
 * Merges and pads an image section's segments until they all are page-aligned
 * and have a size that is a multiple of the page size
 */
static
BOOLEAN
NTAPI
MmspPageAlignSegments
(
 IN OUT PMM_IMAGE_SECTION_OBJECT ImageSectionObject,
 IN ULONG Flags
)
{
   ULONG i;
   ULONG LastSegment;
   PMM_SECTION_SEGMENT EffectiveSegment;

   if (Flags & EXEFMT_LOAD_ASSUME_SEGMENTS_PAGE_ALIGNED)
   {
      MmspAssertSegmentsPageAligned(ImageSectionObject);
      return TRUE;
   }

   LastSegment = 0;
   EffectiveSegment = &ImageSectionObject->Segments[LastSegment];

   for ( i = 0; i < ImageSectionObject->NrSegments; ++ i )
   {
      /*
       * The first segment requires special handling
       */
      if (i == 0)
      {
         ULONG_PTR VirtualAddress;
         ULONG_PTR VirtualOffset;

         VirtualAddress = EffectiveSegment->VirtualAddress;

         /* Round down the virtual address to the nearest page */
         EffectiveSegment->VirtualAddress = PAGE_ROUND_DOWN(VirtualAddress);

         /* Round up the virtual size to the nearest page */
         EffectiveSegment->Length = PAGE_ROUND_UP(VirtualAddress + EffectiveSegment->Length) -
                                    EffectiveSegment->VirtualAddress;

         /* Adjust the raw address and size */
         VirtualOffset = VirtualAddress - EffectiveSegment->VirtualAddress;

         if (EffectiveSegment->FileOffset < VirtualOffset)
         {
            return FALSE;
         }

         /*
          * Garbage in, garbage out: unaligned base addresses make the file
          * offset point in curious and odd places, but that's what we were
          * asked for
          */
         EffectiveSegment->FileOffset -= VirtualOffset;
         EffectiveSegment->RawLength += VirtualOffset;
      }
      else
      {
         PMM_SECTION_SEGMENT Segment = &ImageSectionObject->Segments[i];
         ULONG_PTR EndOfEffectiveSegment;

         EndOfEffectiveSegment = EffectiveSegment->VirtualAddress + EffectiveSegment->Length;
         ASSERT((EndOfEffectiveSegment % PAGE_SIZE) == 0);

         /*
          * The current segment begins exactly where the current effective
          * segment ended, therefore beginning a new effective segment
          */
         if (EndOfEffectiveSegment == Segment->VirtualAddress)
         {
            LastSegment ++;
            ASSERT(LastSegment <= i);
            ASSERT(LastSegment < ImageSectionObject->NrSegments);

            EffectiveSegment = &ImageSectionObject->Segments[LastSegment];

            if (LastSegment != i)
            {
               /*
                * Copy the current segment. If necessary, the effective segment
                * will be expanded later
                */
               *EffectiveSegment = *Segment;
            }

            /*
             * Page-align the virtual size. We know for sure the virtual address
             * already is
             */
            ASSERT((EffectiveSegment->VirtualAddress % PAGE_SIZE) == 0);
            EffectiveSegment->Length = PAGE_ROUND_UP(EffectiveSegment->Length);
         }
         /*
          * The current segment is still part of the current effective segment:
          * extend the effective segment to reflect this
          */
         else if (EndOfEffectiveSegment > Segment->VirtualAddress)
         {
            static const ULONG FlagsToProtection[16] =
            {
               PAGE_NOACCESS,
               PAGE_READONLY,
               PAGE_READWRITE,
               PAGE_READWRITE,
               PAGE_EXECUTE_READ,
               PAGE_EXECUTE_READ,
               PAGE_EXECUTE_READWRITE,
               PAGE_EXECUTE_READWRITE,
               PAGE_WRITECOPY,
               PAGE_WRITECOPY,
               PAGE_WRITECOPY,
               PAGE_WRITECOPY,
               PAGE_EXECUTE_WRITECOPY,
               PAGE_EXECUTE_WRITECOPY,
               PAGE_EXECUTE_WRITECOPY,
               PAGE_EXECUTE_WRITECOPY
            };

            unsigned ProtectionFlags;

            /*
             * Extend the file size
             */

            /* Unaligned segments must be contiguous within the file */
            if (Segment->FileOffset != (EffectiveSegment->FileOffset +
                                        EffectiveSegment->RawLength))
            {
               return FALSE;
            }

            EffectiveSegment->RawLength += Segment->RawLength;

            /*
             * Extend the virtual size
             */
            ASSERT(PAGE_ROUND_UP(Segment->VirtualAddress + Segment->Length) >= EndOfEffectiveSegment);

            EffectiveSegment->Length = PAGE_ROUND_UP(Segment->VirtualAddress + Segment->Length) -
                                       EffectiveSegment->VirtualAddress;

            /*
             * Merge the protection
             */
            EffectiveSegment->Protection |= Segment->Protection;

            /* Clean up redundance */
            ProtectionFlags = 0;

            if(EffectiveSegment->Protection & PAGE_IS_READABLE)
               ProtectionFlags |= 1 << 0;

            if(EffectiveSegment->Protection & PAGE_IS_WRITABLE)
               ProtectionFlags |= 1 << 1;

            if(EffectiveSegment->Protection & PAGE_IS_EXECUTABLE)
               ProtectionFlags |= 1 << 2;

            if(EffectiveSegment->Protection & PAGE_IS_WRITECOPY)
               ProtectionFlags |= 1 << 3;

            ASSERT(ProtectionFlags < 16);
            EffectiveSegment->Protection = FlagsToProtection[ProtectionFlags];

            /* If a segment was required to be shared and cannot, fail */
            if(!(Segment->Protection & PAGE_IS_WRITECOPY) &&
               EffectiveSegment->Protection & PAGE_IS_WRITECOPY)
            {
               return FALSE;
            }
         }
         /*
          * We assume no holes between segments at this point
          */
         else
         {
            KeBugCheck(MEMORY_MANAGEMENT);
         }
      }
   }
   ImageSectionObject->NrSegments = LastSegment + 1;

   return TRUE;
}

NTSTATUS
ExeFmtpCreateImageSection(HANDLE FileHandle,
                          PMM_IMAGE_SECTION_OBJECT ImageSectionObject)
{
   LARGE_INTEGER Offset;
   PVOID FileHeader;
   PVOID FileHeaderBuffer;
   ULONG FileHeaderSize;
   ULONG Flags;
   ULONG OldNrSegments;
   NTSTATUS Status;
   ULONG i;

   /*
    * Read the beginning of the file (2 pages). Should be enough to contain
    * all (or most) of the headers
    */
   Offset.QuadPart = 0;

   /* FIXME: use FileObject instead of FileHandle */
   Status = ExeFmtpReadFile (FileHandle,
                             &Offset,
                             PAGE_SIZE * 2,
                             &FileHeader,
                             &FileHeaderBuffer,
                             &FileHeaderSize);

   if (!NT_SUCCESS(Status))
      return Status;

   if (FileHeaderSize == 0)
   {
      ExFreePool(FileHeaderBuffer);
      return STATUS_UNSUCCESSFUL;
   }

   /*
    * Look for a loader that can handle this executable
    */
   for (i = 0; i < RTL_NUMBER_OF(ExeFmtpLoaders); ++ i)
   {
      RtlZeroMemory(ImageSectionObject, sizeof(*ImageSectionObject));
      Flags = 0;

      /* FIXME: use FileObject instead of FileHandle */
      Status = ExeFmtpLoaders[i](FileHeader,
                                 FileHeaderSize,
                                 FileHandle,
                                 ImageSectionObject,
                                 &Flags,
                                 ExeFmtpReadFile,
                                 ExeFmtpAllocateSegments);

      if (!NT_SUCCESS(Status))
      {
         if (ImageSectionObject->Segments)
         {
            ExFreePool(ImageSectionObject->Segments);
            ImageSectionObject->Segments = NULL;
         }
      }

      if (Status != STATUS_ROS_EXEFMT_UNKNOWN_FORMAT)
         break;
   }

   ExFreePoolWithTag(FileHeaderBuffer, 'rXmM');

   /*
    * No loader handled the format
    */
   if (Status == STATUS_ROS_EXEFMT_UNKNOWN_FORMAT)
   {
      Status = STATUS_INVALID_IMAGE_NOT_MZ;
      ASSERT(!NT_SUCCESS(Status));
   }

   if (!NT_SUCCESS(Status))
      return Status;

   ASSERT(ImageSectionObject->Segments != NULL);

   /*
    * Some defaults
    */
   /* FIXME? are these values platform-dependent? */
   if(ImageSectionObject->StackReserve == 0)
      ImageSectionObject->StackReserve = 0x40000;

   if(ImageSectionObject->StackCommit == 0)
      ImageSectionObject->StackCommit = 0x1000;

   if(ImageSectionObject->ImageBase == 0)
   {
      if(ImageSectionObject->ImageCharacteristics & IMAGE_FILE_DLL)
         ImageSectionObject->ImageBase = 0x10000000;
      else
         ImageSectionObject->ImageBase = 0x00400000;
   }

   /*
    * And now the fun part: fixing the segments
    */

   /* Sort them by virtual address */
   MmspSortSegments(ImageSectionObject, Flags);

   /* Ensure they don't overlap in memory */
   if (!MmspCheckSegmentBounds(ImageSectionObject, Flags))
      return STATUS_INVALID_IMAGE_FORMAT;

   /* Ensure they are aligned */
   OldNrSegments = ImageSectionObject->NrSegments;

   if (!MmspPageAlignSegments(ImageSectionObject, Flags))
      return STATUS_INVALID_IMAGE_FORMAT;

   /* Trim them if the alignment phase merged some of them */
   if (ImageSectionObject->NrSegments < OldNrSegments)
   {
      PMM_SECTION_SEGMENT Segments;
      SIZE_T SizeOfSegments;

      SizeOfSegments = sizeof(MM_SECTION_SEGMENT) * ImageSectionObject->NrSegments;

      Segments = ExAllocatePoolWithTag(PagedPool,
                                       SizeOfSegments,
                                       TAG_MM_SECTION_SEGMENT);

      if (Segments == NULL)
         return STATUS_INSUFFICIENT_RESOURCES;

      RtlCopyMemory(Segments, ImageSectionObject->Segments, SizeOfSegments);
      ExFreePool(ImageSectionObject->Segments);
      ImageSectionObject->Segments = Segments;
   }

   /* And finish their initialization */
   for ( i = 0; i < ImageSectionObject->NrSegments; ++ i )
   {
      ExInitializeFastMutex(&ImageSectionObject->Segments[i].Lock);
      ImageSectionObject->Segments[i].ReferenceCount = 1;

      RtlZeroMemory(&ImageSectionObject->Segments[i].PageDirectory,
                    sizeof(ImageSectionObject->Segments[i].PageDirectory));
   }

   ASSERT(NT_SUCCESS(Status));
   return Status;
}

NTSTATUS
MmCreateImageSection(PROS_SECTION_OBJECT *SectionObject,
                     ACCESS_MASK DesiredAccess,
                     POBJECT_ATTRIBUTES ObjectAttributes,
                     PLARGE_INTEGER UMaximumSize,
                     ULONG SectionPageProtection,
                     ULONG AllocationAttributes,
                     HANDLE FileHandle)
{
   PROS_SECTION_OBJECT Section;
   NTSTATUS Status;
   PFILE_OBJECT FileObject;
   PMM_SECTION_SEGMENT SectionSegments;
   PMM_IMAGE_SECTION_OBJECT ImageSectionObject;
   ULONG i;
   ULONG FileAccess = 0;

   /*
    * Check file access required
    */
   if (SectionPageProtection & PAGE_READWRITE ||
         SectionPageProtection & PAGE_EXECUTE_READWRITE)
   {
      FileAccess = FILE_READ_DATA | FILE_WRITE_DATA;
   }
   else
   {
      FileAccess = FILE_READ_DATA;
   }

   /*
    * Reference the file handle
    */
   Status = ObReferenceObjectByHandle(FileHandle,
                                      FileAccess,
                                      IoFileObjectType,
                                      ExGetPreviousMode(),
                                      (PVOID*)(PVOID)&FileObject,
                                      NULL);

   if (!NT_SUCCESS(Status))
   {
      return Status;
   }

   /*
    * Create the section
    */
   Status = ObCreateObject (ExGetPreviousMode(),
                            MmSectionObjectType,
                            ObjectAttributes,
                            ExGetPreviousMode(),
                            NULL,
                            sizeof(ROS_SECTION_OBJECT),
                            0,
                            0,
                            (PVOID*)(PVOID)&Section);
   if (!NT_SUCCESS(Status))
   {
      ObDereferenceObject(FileObject);
      return(Status);
   }

   /*
    * Initialize it
    */
   RtlZeroMemory(Section, sizeof(ROS_SECTION_OBJECT));
   Section->SectionPageProtection = SectionPageProtection;
   Section->AllocationAttributes = AllocationAttributes;

   /*
    * Initialized caching for this file object if previously caching
    * was initialized for the same on disk file
    */
   Status = CcTryToInitializeFileCache(FileObject);

   if (!NT_SUCCESS(Status) || FileObject->SectionObjectPointer->ImageSectionObject == NULL)
   {
      NTSTATUS StatusExeFmt;

      ImageSectionObject = ExAllocatePoolWithTag(PagedPool, sizeof(MM_IMAGE_SECTION_OBJECT), TAG_MM_SECTION_SEGMENT);
      if (ImageSectionObject == NULL)
      {
         ObDereferenceObject(FileObject);
         ObDereferenceObject(Section);
         return(STATUS_NO_MEMORY);
      }

      RtlZeroMemory(ImageSectionObject, sizeof(MM_IMAGE_SECTION_OBJECT));

      StatusExeFmt = ExeFmtpCreateImageSection(FileHandle, ImageSectionObject);

      if (!NT_SUCCESS(StatusExeFmt))
      {
         if(ImageSectionObject->Segments != NULL)
            ExFreePool(ImageSectionObject->Segments);

         ExFreePool(ImageSectionObject);
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return(StatusExeFmt);
      }

      Section->ImageSection = ImageSectionObject;
      ASSERT(ImageSectionObject->Segments);

      /*
       * Lock the file
       */
      Status = MmspWaitForFileLock(FileObject);
      if (!NT_SUCCESS(Status))
      {
         ExFreePool(ImageSectionObject->Segments);
         ExFreePool(ImageSectionObject);
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return(Status);
      }

      if (NULL != InterlockedCompareExchangePointer(&FileObject->SectionObjectPointer->ImageSectionObject,
                                                    ImageSectionObject, NULL))
      {
         /*
          * An other thread has initialized the same image in the background
          */
         ExFreePool(ImageSectionObject->Segments);
         ExFreePool(ImageSectionObject);
         ImageSectionObject = FileObject->SectionObjectPointer->ImageSectionObject;
         Section->ImageSection = ImageSectionObject;
         SectionSegments = ImageSectionObject->Segments;

         for (i = 0; i < ImageSectionObject->NrSegments; i++)
         {
            (void)InterlockedIncrementUL(&SectionSegments[i].ReferenceCount);
         }
      }

      Status = StatusExeFmt;
   }
   else
   {
      /*
       * Lock the file
       */
      Status = MmspWaitForFileLock(FileObject);
      if (Status != STATUS_SUCCESS)
      {
         ObDereferenceObject(Section);
         ObDereferenceObject(FileObject);
         return(Status);
      }

      ImageSectionObject = FileObject->SectionObjectPointer->ImageSectionObject;
      Section->ImageSection = ImageSectionObject;
      SectionSegments = ImageSectionObject->Segments;

      /*
       * Otherwise just reference all the section segments
       */
      for (i = 0; i < ImageSectionObject->NrSegments; i++)
      {
         (void)InterlockedIncrementUL(&SectionSegments[i].ReferenceCount);
      }

      Status = STATUS_SUCCESS;
   }
   Section->FileObject = FileObject;
   CcRosReferenceCache(FileObject);
   //KeSetEvent((PVOID)&FileObject->Lock, IO_NO_INCREMENT, FALSE);
   *SectionObject = Section;
   return(Status);
}



static NTSTATUS
MmMapViewOfSegment(PMMSUPPORT AddressSpace,
                   PROS_SECTION_OBJECT Section,
                   PMM_SECTION_SEGMENT Segment,
                   PVOID* BaseAddress,
                   SIZE_T ViewSize,
                   ULONG Protect,
                   ULONG ViewOffset,
                   ULONG AllocationType)
{
   PMEMORY_AREA MArea;
   NTSTATUS Status;
   PHYSICAL_ADDRESS BoundaryAddressMultiple;

   BoundaryAddressMultiple.QuadPart = 0;

   Status = MmCreateMemoryArea(AddressSpace,
                               MEMORY_AREA_SECTION_VIEW,
                               BaseAddress,
                               ViewSize,
                               Protect,
                               &MArea,
                               FALSE,
                               AllocationType,
                               BoundaryAddressMultiple);
   if (!NT_SUCCESS(Status))
   {
      DPRINT1("Mapping between 0x%.8X and 0x%.8X failed (%X).\n",
              (*BaseAddress), (char*)(*BaseAddress) + ViewSize, Status);
      return(Status);
   }

   ObReferenceObject((PVOID)Section);

   MArea->Data.SectionData.Segment = Segment;
   MArea->Data.SectionData.Section = Section;
   MArea->Data.SectionData.ViewOffset = ViewOffset;
   MmInitializeRegion(&MArea->Data.SectionData.RegionListHead,
                      ViewSize, 0, Protect);

   return(STATUS_SUCCESS);
}



static VOID
MmFreeSectionPage(PVOID Context, MEMORY_AREA* MemoryArea, PVOID Address,
                  PFN_NUMBER Page, SWAPENTRY SwapEntry, BOOLEAN Dirty)
{
   ULONG Entry;
   PFILE_OBJECT FileObject;
   PBCB Bcb;
   ULONG Offset;
   SWAPENTRY SavedSwapEntry;
   PMM_PAGEOP PageOp;
   NTSTATUS Status;
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;
   PMMSUPPORT AddressSpace;
   PEPROCESS Process;

   AddressSpace = (PMMSUPPORT)Context;
   Process = MmGetAddressSpaceOwner(AddressSpace);

   Address = (PVOID)PAGE_ROUND_DOWN(Address);

   Offset = ((ULONG_PTR)Address - (ULONG_PTR)MemoryArea->StartingAddress) +
            MemoryArea->Data.SectionData.ViewOffset;

   Section = MemoryArea->Data.SectionData.Section;
   Segment = MemoryArea->Data.SectionData.Segment;

   PageOp = MmCheckForPageOp(MemoryArea, NULL, NULL, Segment, Offset);

   while (PageOp)
   {
      MmUnlockSectionSegment(Segment);
      MmUnlockAddressSpace(AddressSpace);

      Status = MmspWaitForPageOpCompletionEvent(PageOp);
      if (Status != STATUS_SUCCESS)
      {
         DPRINT1("Failed to wait for page op, status = %x\n", Status);
         KeBugCheck(MEMORY_MANAGEMENT);
      }

      MmLockAddressSpace(AddressSpace);
      MmLockSectionSegment(Segment);
      MmspCompleteAndReleasePageOp(PageOp);
      PageOp = MmCheckForPageOp(MemoryArea, NULL, NULL, Segment, Offset);
   }

   Entry = MmGetPageEntrySectionSegment(Segment, Offset);

   /*
    * For a dirty, datafile, non-private page mark it as dirty in the
    * cache manager.
    */
   if (Segment->Flags & MM_DATAFILE_SEGMENT)
   {
      if (Page == PFN_FROM_SSE(Entry) && Dirty)
      {
         FileObject = MemoryArea->Data.SectionData.Section->FileObject;
         Bcb = FileObject->SectionObjectPointer->SharedCacheMap;
         CcRosMarkDirtyCacheSegment(Bcb, Offset + Segment->FileOffset);
         ASSERT(SwapEntry == 0);
      }
   }

   if (SwapEntry != 0)
   {
      /*
       * Sanity check
       */
      if (Segment->Flags & MM_PAGEFILE_SEGMENT)
      {
         DPRINT1("Found a swap entry for a page in a pagefile section.\n");
         KeBugCheck(MEMORY_MANAGEMENT);
      }
      MmFreeSwapPage(SwapEntry);
   }
   else if (Page != 0)
   {
      if (IS_SWAP_FROM_SSE(Entry) ||
          Page != PFN_FROM_SSE(Entry))
      {
         /*
          * Sanity check
          */
         if (Segment->Flags & MM_PAGEFILE_SEGMENT)
         {
            DPRINT1("Found a private page in a pagefile section.\n");
            KeBugCheck(MEMORY_MANAGEMENT);
         }
         /*
          * Just dereference private pages
          */
         SavedSwapEntry = MmGetSavedSwapEntryPage(Page);
         if (SavedSwapEntry != 0)
         {
            MmFreeSwapPage(SavedSwapEntry);
            MmSetSavedSwapEntryPage(Page, 0);
         }
         MmDeleteRmap(Page, Process, Address);
         MmReleasePageMemoryConsumer(MC_USER, Page);
      }
      else
      {
         MmDeleteRmap(Page, Process, Address);
         MmUnsharePageEntrySectionSegment(Section, Segment, Offset, Dirty, FALSE);
      }
   }
}

static NTSTATUS
MmUnmapViewOfSegment(PMMSUPPORT AddressSpace,
                     PVOID BaseAddress)
{
   NTSTATUS Status;
   PMEMORY_AREA MemoryArea;
   PROS_SECTION_OBJECT Section;
   PMM_SECTION_SEGMENT Segment;
   PLIST_ENTRY CurrentEntry;
   PMM_REGION CurrentRegion;
   PLIST_ENTRY RegionListHead;

   MemoryArea = MmLocateMemoryAreaByAddress(AddressSpace,
                                            BaseAddress);
   if (MemoryArea == NULL)
   {
      return(STATUS_UNSUCCESSFUL);
   }

   MemoryArea->DeleteInProgress = TRUE;
   Section = MemoryArea->Data.SectionData.Section;
   Segment = MemoryArea->Data.SectionData.Segment;

   MmLockSectionSegment(Segment);

   RegionListHead = &MemoryArea->Data.SectionData.RegionListHead;
   while (!IsListEmpty(RegionListHead))
   {
      CurrentEntry = RemoveHeadList(RegionListHead);
      CurrentRegion = CONTAINING_RECORD(CurrentEntry, MM_REGION, RegionListEntry);
      ExFreePoolWithTag(CurrentRegion, TAG_MM_REGION);
   }

   if (Section->AllocationAttributes & SEC_PHYSICALMEMORY)
   {
      Status = MmFreeMemoryArea(AddressSpace,
                                MemoryArea,
                                NULL,
                                NULL);
   }
   else
   {
      Status = MmFreeMemoryArea(AddressSpace,
                                MemoryArea,
                                MmFreeSectionPage,
                                AddressSpace);
   }
   MmUnlockSectionSegment(Segment);
   ObDereferenceObject(Section);
   return(Status);
}

/*
 * @implemented
 */
NTSTATUS NTAPI
MmUnmapViewOfSection(PEPROCESS Process,
                     PVOID BaseAddress)
{
   NTSTATUS Status;
   PMEMORY_AREA MemoryArea;
   PMMSUPPORT AddressSpace;
   PROS_SECTION_OBJECT Section;
   PMM_PAGEOP PageOp;
   ULONG_PTR Offset;
    PVOID ImageBaseAddress = 0;

   DPRINT("Opening memory area Process %x BaseAddress %x\n",
          Process, BaseAddress);

   ASSERT(Process);

   AddressSpace = &Process->Vm;

   MmLockAddressSpace(AddressSpace);
   MemoryArea = MmLocateMemoryAreaByAddress(AddressSpace,
                                            BaseAddress);
   if (MemoryArea == NULL ||
       MemoryArea->Type != MEMORY_AREA_SECTION_VIEW ||
       MemoryArea->DeleteInProgress)
   {
      MmUnlockAddressSpace(AddressSpace);
      return STATUS_NOT_MAPPED_VIEW;
   }

   MemoryArea->DeleteInProgress = TRUE;

   while (MemoryArea->PageOpCount)
   {
      Offset = PAGE_ROUND_UP((ULONG_PTR)MemoryArea->EndingAddress - (ULONG_PTR)MemoryArea->StartingAddress);

      while (Offset)
      {
         Offset -= PAGE_SIZE;
         PageOp = MmCheckForPageOp(MemoryArea, NULL, NULL,
                                   MemoryArea->Data.SectionData.Segment,
                                   Offset + MemoryArea->Data.SectionData.ViewOffset);
         if (PageOp)
         {
            MmUnlockAddressSpace(AddressSpace);
            Status = MmspWaitForPageOpCompletionEvent(PageOp);
            if (Status != STATUS_SUCCESS)
            {
               DPRINT1("Failed to wait for page op, status = %x\n", Status);
               KeBugCheck(MEMORY_MANAGEMENT);
            }
            MmLockAddressSpace(AddressSpace);
            MemoryArea = MmLocateMemoryAreaByAddress(AddressSpace,
                                                     BaseAddress);
            if (MemoryArea == NULL ||
                MemoryArea->Type != MEMORY_AREA_SECTION_VIEW)
            {
               MmUnlockAddressSpace(AddressSpace);
               return STATUS_NOT_MAPPED_VIEW;
            }
            break;
         }
      }
   }

   Section = MemoryArea->Data.SectionData.Section;

   if (Section->AllocationAttributes & SEC_IMAGE)
   {
      ULONG i;
      ULONG NrSegments;
      PMM_IMAGE_SECTION_OBJECT ImageSectionObject;
      PMM_SECTION_SEGMENT SectionSegments;
      PMM_SECTION_SEGMENT Segment;

      Segment = MemoryArea->Data.SectionData.Segment;
      ImageSectionObject = Section->ImageSection;
      SectionSegments = ImageSectionObject->Segments;
      NrSegments = ImageSectionObject->NrSegments;

      /* Search for the current segment within the section segments
       * and calculate the image base address */
      for (i = 0; i < NrSegments; i++)
      {
         if (!(SectionSegments[i].Characteristics & IMAGE_SCN_TYPE_NOLOAD))
         {
            if (Segment == &SectionSegments[i])
            {
               ImageBaseAddress = (char*)BaseAddress - (ULONG_PTR)SectionSegments[i].VirtualAddress;
               break;
            }
         }
      }
      if (i >= NrSegments)
      {
         KeBugCheck(MEMORY_MANAGEMENT);
      }

      for (i = 0; i < NrSegments; i++)
      {
         if (!(SectionSegments[i].Characteristics & IMAGE_SCN_TYPE_NOLOAD))
         {
            PVOID SBaseAddress = (PVOID)
                                 ((char*)ImageBaseAddress + (ULONG_PTR)SectionSegments[i].VirtualAddress);

            Status = MmUnmapViewOfSegment(AddressSpace, SBaseAddress);
         }
      }
   }
   else
   {
      Status = MmUnmapViewOfSegment(AddressSpace, BaseAddress);
   }

   MmUnlockAddressSpace(AddressSpace);

   /* Notify debugger */
   if (ImageBaseAddress) DbgkUnMapViewOfSection(ImageBaseAddress);

   return(STATUS_SUCCESS);
}




/**
 * Queries the information of a section object.
 *
 * @param SectionHandle
 *        Handle to the section object. It must be opened with SECTION_QUERY
 *        access.
 * @param SectionInformationClass
 *        Index to a certain information structure. Can be either
 *        SectionBasicInformation or SectionImageInformation. The latter
 *        is valid only for sections that were created with the SEC_IMAGE
 *        flag.
 * @param SectionInformation
 *        Caller supplies storage for resulting information.
 * @param Length
 *        Size of the supplied storage.
 * @param ResultLength
 *        Data written.
 *
 * @return Status.
 *
 * @implemented
 */
NTSTATUS NTAPI
NtQuerySection(IN HANDLE SectionHandle,
               IN SECTION_INFORMATION_CLASS SectionInformationClass,
               OUT PVOID SectionInformation,
               IN SIZE_T SectionInformationLength,
               OUT PSIZE_T ResultLength  OPTIONAL)
{
   PROS_SECTION_OBJECT Section;
   KPROCESSOR_MODE PreviousMode;
   NTSTATUS Status;
   PAGED_CODE();

   PreviousMode = ExGetPreviousMode();

   Status = DefaultQueryInfoBufferCheck(SectionInformationClass,
                                        ExSectionInfoClass,
                                        sizeof(ExSectionInfoClass) / sizeof(ExSectionInfoClass[0]),
                                        SectionInformation,
                                        SectionInformationLength,
                                        NULL,
                                        ResultLength,
                                        PreviousMode);

   if(!NT_SUCCESS(Status))
   {
     DPRINT1("NtQuerySection() failed, Status: 0x%x\n", Status);
     return Status;
   }

   Status = ObReferenceObjectByHandle(SectionHandle,
                                      SECTION_QUERY,
                                      MmSectionObjectType,
                                      PreviousMode,
                                      (PVOID*)(PVOID)&Section,
                                      NULL);
   if (NT_SUCCESS(Status))
   {
      switch (SectionInformationClass)
      {
         case SectionBasicInformation:
         {
            PSECTION_BASIC_INFORMATION Sbi = (PSECTION_BASIC_INFORMATION)SectionInformation;

            _SEH2_TRY
            {
               Sbi->Attributes = Section->AllocationAttributes;
               if (Section->AllocationAttributes & SEC_IMAGE)
               {
                  Sbi->BaseAddress = 0;
                  Sbi->Size.QuadPart = 0;
               }
               else
               {
                  Sbi->BaseAddress = (PVOID)Section->Segment->VirtualAddress;
                  Sbi->Size.QuadPart = Section->Segment->Length;
               }

               if (ResultLength != NULL)
               {
                  *ResultLength = sizeof(SECTION_BASIC_INFORMATION);
               }
               Status = STATUS_SUCCESS;
            }
            _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
            {
               Status = _SEH2_GetExceptionCode();
            }
            _SEH2_END;

            break;
         }

         case SectionImageInformation:
         {
            PSECTION_IMAGE_INFORMATION Sii = (PSECTION_IMAGE_INFORMATION)SectionInformation;

            _SEH2_TRY
            {
               memset(Sii, 0, sizeof(SECTION_IMAGE_INFORMATION));
               if (Section->AllocationAttributes & SEC_IMAGE)
               {
                  PMM_IMAGE_SECTION_OBJECT ImageSectionObject;
                  ImageSectionObject = Section->ImageSection;

                  Sii->TransferAddress = (PVOID)ImageSectionObject->EntryPoint;
                  Sii->MaximumStackSize = ImageSectionObject->StackReserve;
                  Sii->CommittedStackSize = ImageSectionObject->StackCommit;
                  Sii->SubSystemType = ImageSectionObject->Subsystem;
                  Sii->SubSystemMinorVersion = ImageSectionObject->MinorSubsystemVersion;
                  Sii->SubSystemMajorVersion = ImageSectionObject->MajorSubsystemVersion;
                  Sii->ImageCharacteristics = ImageSectionObject->ImageCharacteristics;
                  Sii->Machine = ImageSectionObject->Machine;
                  Sii->ImageContainsCode = ImageSectionObject->Executable;
               }

               if (ResultLength != NULL)
               {
                  *ResultLength = sizeof(SECTION_IMAGE_INFORMATION);
               }
               Status = STATUS_SUCCESS;
            }
            _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
            {
               Status = _SEH2_GetExceptionCode();
            }
            _SEH2_END;

            break;
         }
      }

      ObDereferenceObject(Section);
   }

   return(Status);
}
                       
/**********************************************************************
 * NAME       EXPORTED
 * MmMapViewOfSection
 *
 * DESCRIPTION
 * Maps a view of a section into the virtual address space of a
 * process.
 *
 * ARGUMENTS
 * Section
 *  Pointer to the section object.
 *
 * ProcessHandle
 *  Pointer to the process.
 *
 * BaseAddress
 *  Desired base address (or NULL) on entry;
 *  Actual base address of the view on exit.
 *
 * ZeroBits
 *  Number of high order address bits that must be zero.
 *
 * CommitSize
 *  Size in bytes of the initially committed section of
 *  the view.
 *
 * SectionOffset
 *  Offset in bytes from the beginning of the section
 *  to the beginning of the view.
 *
 * ViewSize
 *  Desired length of map (or zero to map all) on entry
 *  Actual length mapped on exit.
 *
 * InheritDisposition
 *  Specified how the view is to be shared with
 *  child processes.
 *
 * AllocationType
 *  Type of allocation for the pages.
 *
 * Protect
 *  Protection for the committed region of the view.
 *
 * RETURN VALUE
 * Status.
 *
 * @implemented
 */
NTSTATUS NTAPI
MmMapViewOfSection(IN PVOID SectionObject,
                   IN PEPROCESS Process,
                   IN OUT PVOID *BaseAddress,
                   IN ULONG_PTR ZeroBits,
                   IN SIZE_T CommitSize,
                   IN OUT PLARGE_INTEGER SectionOffset OPTIONAL,
                   IN OUT PSIZE_T ViewSize,
                   IN SECTION_INHERIT InheritDisposition,
                   IN ULONG AllocationType,
                   IN ULONG Protect)
{
   PROS_SECTION_OBJECT Section;
   PMMSUPPORT AddressSpace;
   ULONG ViewOffset;
   NTSTATUS Status = STATUS_SUCCESS;

   if ((ULONG_PTR)SectionObject & 1)
   {
       return MmMapViewOfArm3Section((PVOID)((ULONG_PTR)SectionObject & ~1),
                                     Process,
                                     BaseAddress,
                                     ZeroBits,
                                     CommitSize,
                                     SectionOffset,
                                     ViewSize,
                                     InheritDisposition,
                                     AllocationType,
                                     Protect);
   }
   
   ASSERT(Process);

   if (!Protect || Protect & ~PAGE_FLAGS_VALID_FOR_SECTION)
   {
      return STATUS_INVALID_PAGE_PROTECTION;
   }


   Section = (PROS_SECTION_OBJECT)SectionObject;
   AddressSpace = &Process->Vm;

   AllocationType |= (Section->AllocationAttributes & SEC_NO_CHANGE);

   MmLockAddressSpace(AddressSpace);

   if (Section->AllocationAttributes & SEC_IMAGE)
   {
      ULONG i;
      ULONG NrSegments;
      ULONG_PTR ImageBase;
      ULONG ImageSize;
      PMM_IMAGE_SECTION_OBJECT ImageSectionObject;
      PMM_SECTION_SEGMENT SectionSegments;

      ImageSectionObject = Section->ImageSection;
      SectionSegments = ImageSectionObject->Segments;
      NrSegments = ImageSectionObject->NrSegments;


      ImageBase = (ULONG_PTR)*BaseAddress;
      if (ImageBase == 0)
      {
         ImageBase = ImageSectionObject->ImageBase;
      }

      ImageSize = 0;
      for (i = 0; i < NrSegments; i++)
      {
         if (!(SectionSegments[i].Characteristics & IMAGE_SCN_TYPE_NOLOAD))
         {
            ULONG_PTR MaxExtent;
            MaxExtent = (ULONG_PTR)SectionSegments[i].VirtualAddress +
                        SectionSegments[i].Length;
            ImageSize = max(ImageSize, MaxExtent);
         }
      }

      ImageSectionObject->ImageSize = ImageSize;

      /* Check there is enough space to map the section at that point. */
      if (MmLocateMemoryAreaByRegion(AddressSpace, (PVOID)ImageBase,
                                     PAGE_ROUND_UP(ImageSize)) != NULL)
      {
         /* Fail if the user requested a fixed base address. */
         if ((*BaseAddress) != NULL)
         {
            MmUnlockAddressSpace(AddressSpace);
            return(STATUS_UNSUCCESSFUL);
         }
         /* Otherwise find a gap to map the image. */
         ImageBase = (ULONG_PTR)MmFindGap(AddressSpace, PAGE_ROUND_UP(ImageSize), PAGE_SIZE, FALSE);
         if (ImageBase == 0)
         {
            MmUnlockAddressSpace(AddressSpace);
            return(STATUS_UNSUCCESSFUL);
         }
      }

      for (i = 0; i < NrSegments; i++)
      {
         if (!(SectionSegments[i].Characteristics & IMAGE_SCN_TYPE_NOLOAD))
         {
            PVOID SBaseAddress = (PVOID)
                                 ((char*)ImageBase + (ULONG_PTR)SectionSegments[i].VirtualAddress);
            MmLockSectionSegment(&SectionSegments[i]);
            Status = MmMapViewOfSegment(AddressSpace,
                                        Section,
                                        &SectionSegments[i],
                                        &SBaseAddress,
                                        SectionSegments[i].Length,
                                        SectionSegments[i].Protection,
                                        0,
                                        0);
            MmUnlockSectionSegment(&SectionSegments[i]);
            if (!NT_SUCCESS(Status))
            {
               MmUnlockAddressSpace(AddressSpace);
               return(Status);
            }
         }
      }

      *BaseAddress = (PVOID)ImageBase;
   }
   else
   {
      /* check for write access */
      if ((Protect & (PAGE_READWRITE|PAGE_EXECUTE_READWRITE)) &&
          !(Section->SectionPageProtection & (PAGE_READWRITE|PAGE_EXECUTE_READWRITE)))
      {
         MmUnlockAddressSpace(AddressSpace);
         return STATUS_SECTION_PROTECTION;
      }
      /* check for read access */
      if ((Protect & (PAGE_READONLY|PAGE_WRITECOPY|PAGE_EXECUTE_READ|PAGE_EXECUTE_WRITECOPY)) &&
          !(Section->SectionPageProtection & (PAGE_READONLY|PAGE_READWRITE|PAGE_WRITECOPY|PAGE_EXECUTE_READ|PAGE_EXECUTE_READWRITE|PAGE_EXECUTE_WRITECOPY)))
      {
         MmUnlockAddressSpace(AddressSpace);
         return STATUS_SECTION_PROTECTION;
      }
      /* check for execute access */
      if ((Protect & (PAGE_EXECUTE|PAGE_EXECUTE_READ|PAGE_EXECUTE_READWRITE|PAGE_EXECUTE_WRITECOPY)) &&
          !(Section->SectionPageProtection & (PAGE_EXECUTE|PAGE_EXECUTE_READ|PAGE_EXECUTE_READWRITE|PAGE_EXECUTE_WRITECOPY)))
      {
         MmUnlockAddressSpace(AddressSpace);
         return STATUS_SECTION_PROTECTION;
      }

      if (ViewSize == NULL)
      {
         /* Following this pointer would lead to us to the dark side */
         /* What to do? Bugcheck? Return status? Do the mambo? */
         KeBugCheck(MEMORY_MANAGEMENT);
      }

      if (SectionOffset == NULL)
      {
         ViewOffset = 0;
      }
      else
      {
         ViewOffset = SectionOffset->u.LowPart;
      }

      if ((ViewOffset % PAGE_SIZE) != 0)
      {
         MmUnlockAddressSpace(AddressSpace);
         return(STATUS_MAPPED_ALIGNMENT);
      }

      if ((*ViewSize) == 0)
      {
         (*ViewSize) = Section->MaximumSize.u.LowPart - ViewOffset;
      }
      else if (((*ViewSize)+ViewOffset) > Section->MaximumSize.u.LowPart)
      {
         (*ViewSize) = Section->MaximumSize.u.LowPart - ViewOffset;
      }

      *ViewSize = PAGE_ROUND_UP(*ViewSize);

      MmLockSectionSegment(Section->Segment);
      Status = MmMapViewOfSegment(AddressSpace,
                                  Section,
                                  Section->Segment,
                                  BaseAddress,
                                  *ViewSize,
                                  Protect,
                                  ViewOffset,
                                  AllocationType & (MEM_TOP_DOWN|SEC_NO_CHANGE));
      MmUnlockSectionSegment(Section->Segment);
      if (!NT_SUCCESS(Status))
      {
         MmUnlockAddressSpace(AddressSpace);
         return(Status);
      }
   }

   MmUnlockAddressSpace(AddressSpace);

   return(STATUS_SUCCESS);
}

/*
 * @unimplemented
 */
BOOLEAN NTAPI
MmCanFileBeTruncated (IN PSECTION_OBJECT_POINTERS SectionObjectPointer,
                      IN PLARGE_INTEGER   NewFileSize)
{
   /* Check whether an ImageSectionObject exists */
   if (SectionObjectPointer->ImageSectionObject != NULL)
   {
      DPRINT1("ERROR: File can't be truncated because it has an image section\n");
      return FALSE;
   }

   if (SectionObjectPointer->DataSectionObject != NULL)
   {
      PMM_SECTION_SEGMENT Segment;

      Segment = (PMM_SECTION_SEGMENT)SectionObjectPointer->
                DataSectionObject;

      if (Segment->ReferenceCount != 0)
      {
          /* Check size of file */
          if (SectionObjectPointer->SharedCacheMap)
          {
             PBCB Bcb = SectionObjectPointer->SharedCacheMap;
             if (NewFileSize->QuadPart <= Bcb->FileSize.QuadPart)
             {
                return FALSE;
             }
          }
      }
      else
      {
         /* Something must gone wrong
          * how can we have a Section but no 
          * reference? */
         DPRINT("ERROR: DataSectionObject without reference!\n");
      }
   }

   DPRINT("FIXME: didn't check for outstanding write probes\n");

   return TRUE;
}




/*
 * @implemented
 */
BOOLEAN NTAPI
MmFlushImageSection (IN PSECTION_OBJECT_POINTERS SectionObjectPointer,
                     IN MMFLUSH_TYPE   FlushType)
{
   switch(FlushType)
   {
      case MmFlushForDelete:
         if (SectionObjectPointer->ImageSectionObject ||
               SectionObjectPointer->DataSectionObject)
         {
            return FALSE;
         }
         CcRosSetRemoveOnClose(SectionObjectPointer);
         return TRUE;
      case MmFlushForWrite:
         break;
   }
   return FALSE;
}

/*
 * @implemented
 */
NTSTATUS NTAPI
MmMapViewInSystemSpace (IN PVOID SectionObject,
                        OUT PVOID * MappedBase,
                        IN OUT PSIZE_T ViewSize)
{
   PROS_SECTION_OBJECT Section;
   PMMSUPPORT AddressSpace;
   NTSTATUS Status;
   PAGED_CODE();
        
    if ((ULONG_PTR)SectionObject & 1)
    {
        extern PVOID MmSession;
        return MiMapViewInSystemSpace((PVOID)((ULONG_PTR)SectionObject & ~1),
                                      &MmSession,
                                      MappedBase,
                                      ViewSize);
    }

   DPRINT("MmMapViewInSystemSpace() called\n");

   Section = (PROS_SECTION_OBJECT)SectionObject;
   AddressSpace = MmGetKernelAddressSpace();

   MmLockAddressSpace(AddressSpace);


   if ((*ViewSize) == 0)
   {
      (*ViewSize) = Section->MaximumSize.u.LowPart;
   }
   else if ((*ViewSize) > Section->MaximumSize.u.LowPart)
   {
      (*ViewSize) = Section->MaximumSize.u.LowPart;
   }

   MmLockSectionSegment(Section->Segment);


   Status = MmMapViewOfSegment(AddressSpace,
                               Section,
                               Section->Segment,
                               MappedBase,
                               *ViewSize,
                               PAGE_READWRITE,
                               0,
                               0);

   MmUnlockSectionSegment(Section->Segment);
   MmUnlockAddressSpace(AddressSpace);

   return Status;
}

/*
 * @implemented
 */
NTSTATUS NTAPI
MmUnmapViewInSystemSpace (IN PVOID MappedBase)
{
   PMMSUPPORT AddressSpace;
   NTSTATUS Status;

   DPRINT("MmUnmapViewInSystemSpace() called\n");

   AddressSpace = MmGetKernelAddressSpace();

   Status = MmUnmapViewOfSegment(AddressSpace, MappedBase);

   return Status;
}


/**********************************************************************
 * NAME       EXPORTED
 *  MmCreateSection@
 *
 * DESCRIPTION
 *  Creates a section object.
 *
 * ARGUMENTS
 * SectionObject (OUT)
 *  Caller supplied storage for the resulting pointer
 *  to a SECTION_OBJECT instance;
 *
 * DesiredAccess
 *  Specifies the desired access to the section can be a
 *  combination of:
 *   STANDARD_RIGHTS_REQUIRED |
 *   SECTION_QUERY   |
 *   SECTION_MAP_WRITE  |
 *   SECTION_MAP_READ  |
 *   SECTION_MAP_EXECUTE
 *
 * ObjectAttributes [OPTIONAL]
 *  Initialized attributes for the object can be used
 *  to create a named section;
 *
 * MaximumSize
 *  Maximizes the size of the memory section. Must be
 *  non-NULL for a page-file backed section.
 *  If value specified for a mapped file and the file is
 *  not large enough, file will be extended.
 *
 * SectionPageProtection
 *  Can be a combination of:
 *   PAGE_READONLY |
 *   PAGE_READWRITE |
 *   PAGE_WRITEONLY |
 *   PAGE_WRITECOPY
 *
 * AllocationAttributes
 *  Can be a combination of:
 *   SEC_IMAGE |
 *   SEC_RESERVE
 *
 * FileHandle
 *  Handle to a file to create a section mapped to a file
 *  instead of a memory backed section;
 *
 * File
 *  Unknown.
 *
 * RETURN VALUE
 *  Status.
 *
 * @implemented
 */
NTSTATUS NTAPI
MmCreateSection (OUT PVOID  * Section,
                 IN ACCESS_MASK  DesiredAccess,
                 IN POBJECT_ATTRIBUTES ObjectAttributes     OPTIONAL,
                 IN PLARGE_INTEGER  MaximumSize,
                 IN ULONG   SectionPageProtection,
                 IN ULONG   AllocationAttributes,
                 IN HANDLE   FileHandle   OPTIONAL,
                 IN PFILE_OBJECT  File      OPTIONAL)
{
   ULONG Protection;
   PROS_SECTION_OBJECT *SectionObject = (PROS_SECTION_OBJECT *)Section;
   
    /* Check if an ARM3 section is being created instead */
    if (AllocationAttributes & 1)
    {
        DPRINT1("arm 3 path\n");
        return MmCreateArm3Section(Section,
                                   DesiredAccess,
                                   ObjectAttributes,
                                   MaximumSize,
                                   SectionPageProtection,
                                   AllocationAttributes &~ 1,
                                   FileHandle,
                                   File);
    }

   /*
    * Check the protection
    */
   Protection = SectionPageProtection & ~(PAGE_GUARD|PAGE_NOCACHE);
   if (Protection != PAGE_READONLY &&
       Protection != PAGE_READWRITE &&
       Protection != PAGE_WRITECOPY &&
       Protection != PAGE_EXECUTE &&
       Protection != PAGE_EXECUTE_READ &&
       Protection != PAGE_EXECUTE_READWRITE &&
       Protection != PAGE_EXECUTE_WRITECOPY)
   {
     return STATUS_INVALID_PAGE_PROTECTION;
   }

   if (AllocationAttributes & SEC_IMAGE)
   {
      return(MmCreateImageSection(SectionObject,
                                  DesiredAccess,
                                  ObjectAttributes,
                                  MaximumSize,
                                  SectionPageProtection,
                                  AllocationAttributes,
                                  FileHandle));
   }

   if (FileHandle != NULL)
   {
      return(MmCreateDataFileSection(SectionObject,
                                     DesiredAccess,
                                     ObjectAttributes,
                                     MaximumSize,
                                     SectionPageProtection,
                                     AllocationAttributes,
                                     FileHandle));
   }

   return(MmCreatePageFileSection(SectionObject,
                                  DesiredAccess,
                                  ObjectAttributes,
                                  MaximumSize,
                                  SectionPageProtection,
                                  AllocationAttributes));
}



/* EOF */