[ros-diffs] [ros-arm-bringup] 34873: The puzzle of the design decisions behind the React address space structure continues to be troubling (perhaps there was no design?). Every time a process address space is initialized, the owner process is stored (which we now use to figure out the lowest address). Recall that NULL means kernel, anything else means per-process. This is great, except that after some painfull header groking, one understands that the PMADDRESS_SPACE structure is actually *not* a separate st

Author: ros-arm-bringup
Date: Sun Jul 27 18:53:04 2008
New Revision: 34873

URL: http://svn.reactos.org/svn/reactos?rev=34873&view=rev
Log:
The puzzle of the design decisions behind the React address space structure continues to
be troubling (perhaps there was no design?). Every time a process address space is
initialized,
the owner process is stored (which we now use to figure out the lowest address). Recall
that NULL means kernel, anything else means per-process. This is great, except that after
some
painfull header groking, one understands that the PMADDRESS_SPACE structure is actually
*not* a separate structure, but embedded within PEPROCESS itself. It is a React-specific
structure
(hence the attempts to get rid of it), that seems to have been "overloaded" on
top of the VadRoot structure that Windows uses for user-mode memory allocations. To
clarify, this structure
is actually embedded inside the process that owns it, except for the kernel address space,
which is a global variable. So there's absolutely *no* point in saving a reference to
the owner
process, since we'll always be embedded inside it (except for kernel address space).
This patch creates the MmGetAddressSpaceOwner macro which either returns NULL for kernel
address space, or uses the CONTAINING_RECORD macro to return the owner (embedded) process.



Modified:
    trunk/reactos/ntoskrnl/include/internal/mm.h
    trunk/reactos/ntoskrnl/mm/anonmem.c
    trunk/reactos/ntoskrnl/mm/aspace.c
    trunk/reactos/ntoskrnl/mm/marea.c
    trunk/reactos/ntoskrnl/mm/section.c

Modified: trunk/reactos/ntoskrnl/include/internal/mm.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/include/internal/…
==============================================================================
--- trunk/reactos/ntoskrnl/include/internal/mm.h [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/include/internal/mm.h [iso-8859-1] Sun Jul 27 18:53:04 2008
@@ -253,7 +253,6 @@
 typedef struct _MADDRESS_SPACE
 {
     PMEMORY_AREA MemoryAreaRoot;
-    PEPROCESS Process;
     PEX_PUSH_LOCK Lock;
 } MADDRESS_SPACE, *PMADDRESS_SPACE;
 
@@ -1589,6 +1588,14 @@
 }
 
 FORCEINLINE
+PEPROCESS
+MmGetAddressSpaceOwner(IN PMADDRESS_SPACE AddressSpace)
+{
+    if (AddressSpace == &MmKernelAddressSpace) return NULL;
+    return CONTAINING_RECORD(AddressSpace, EPROCESS, VadRoot);
+}
+
+FORCEINLINE
 PMADDRESS_SPACE
 MmGetCurrentAddressSpace(VOID)
 {

Modified: trunk/reactos/ntoskrnl/mm/anonmem.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/anonmem.c?rev=…
==============================================================================
--- trunk/reactos/ntoskrnl/mm/anonmem.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/anonmem.c [iso-8859-1] Sun Jul 27 18:53:04 2008
@@ -55,6 +55,7 @@
    SWAPENTRY SwapEntry;
    PFN_TYPE Page;
    NTSTATUS Status;
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
 
    /*
     * Check for paging out from a deleted virtual memory area.
@@ -67,12 +68,12 @@
       return(STATUS_UNSUCCESSFUL);
    }
 
-   Page = MmGetPfnForProcess(AddressSpace->Process, Address);
+   Page = MmGetPfnForProcess(Process, Address);
 
    /*
     * Get that the page actually is dirty.
     */
-   if (!MmIsDirtyPage(AddressSpace->Process, Address))
+   if (!MmIsDirtyPage(Process, Address))
    {
       PageOp->Status = STATUS_SUCCESS;
       KeSetEvent(&PageOp->CompletionEvent, IO_NO_INCREMENT, FALSE);
@@ -83,7 +84,7 @@
    /*
     * Speculatively set the mapping to clean.
     */
-   MmSetCleanPage(AddressSpace->Process, Address);
+   MmSetCleanPage(Process, Address);
 
    /*
     * If necessary, allocate an entry in the paging file for this page
@@ -94,7 +95,7 @@
       SwapEntry = MmAllocSwapPage();
       if (SwapEntry == 0)
       {
-         MmSetDirtyPage(AddressSpace->Process, Address);
+         MmSetDirtyPage(Process, Address);
          PageOp->Status = STATUS_PAGEFILE_QUOTA_EXCEEDED;
          KeSetEvent(&PageOp->CompletionEvent, IO_NO_INCREMENT, FALSE);
          MmReleasePageOp(PageOp);
@@ -110,7 +111,7 @@
    {
       DPRINT1("MM: Failed to write to swap page (Status was 0x%.8X)\n",
               Status);
-      MmSetDirtyPage(AddressSpace->Process, Address);
+      MmSetDirtyPage(Process, Address);
       PageOp->Status = STATUS_UNSUCCESSFUL;
       KeSetEvent(&PageOp->CompletionEvent, IO_NO_INCREMENT, FALSE);
       MmReleasePageOp(PageOp);
@@ -138,9 +139,10 @@
    BOOLEAN WasDirty;
    SWAPENTRY SwapEntry;
    NTSTATUS Status;
-
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
+    
    DPRINT("MmPageOutVirtualMemory(Address 0x%.8X) PID %d\n",
-          Address, AddressSpace->Process->UniqueProcessId);
+          Address, Process->UniqueProcessId);
 
    /*
     * Check for paging out from a deleted virtual memory area.
@@ -156,7 +158,7 @@
    /*
     * Disable the virtual mapping.
     */
-   MmDisableVirtualMapping(AddressSpace->Process, Address,
+   MmDisableVirtualMapping(Process, Address,
                            &WasDirty, &Page);
 
    if (Page == 0)
@@ -170,11 +172,11 @@
    if (!WasDirty)
    {
       MmLockAddressSpace(AddressSpace);
-      MmDeleteVirtualMapping(AddressSpace->Process, Address, FALSE, NULL, NULL);
+      MmDeleteVirtualMapping(Process, Address, FALSE, NULL, NULL);
       MmDeleteAllRmaps(Page, NULL, NULL);
       if ((SwapEntry = MmGetSavedSwapEntryPage(Page)) != 0)
       {
-         MmCreatePageFileMapping(AddressSpace->Process, Address, SwapEntry);
+         MmCreatePageFileMapping(Process, Address, SwapEntry);
          MmSetSavedSwapEntryPage(Page, 0);
       }
       MmUnlockAddressSpace(AddressSpace);
@@ -195,7 +197,7 @@
       if (SwapEntry == 0)
       {
          MmShowOutOfSpaceMessagePagingFile();
-         MmEnableVirtualMapping(AddressSpace->Process, Address);
+         MmEnableVirtualMapping(Process, Address);
          PageOp->Status = STATUS_UNSUCCESSFUL;
          KeSetEvent(&PageOp->CompletionEvent, IO_NO_INCREMENT, FALSE);
          MmReleasePageOp(PageOp);
@@ -211,7 +213,7 @@
    {
       DPRINT1("MM: Failed to write to swap page (Status was 0x%.8X)\n",
               Status);
-      MmEnableVirtualMapping(AddressSpace->Process, Address);
+      MmEnableVirtualMapping(Process, Address);
       PageOp->Status = STATUS_UNSUCCESSFUL;
       KeSetEvent(&PageOp->CompletionEvent, IO_NO_INCREMENT, FALSE);
       MmReleasePageOp(PageOp);
@@ -223,8 +225,8 @@
     */
    DPRINT("MM: Swapped out virtual memory page 0x%.8X!\n", Page <<
PAGE_SHIFT);
    MmLockAddressSpace(AddressSpace);
-   MmDeleteVirtualMapping(AddressSpace->Process, Address, FALSE, NULL, NULL);
-   MmCreatePageFileMapping(AddressSpace->Process, Address, SwapEntry);
+   MmDeleteVirtualMapping(Process, Address, FALSE, NULL, NULL);
+   MmCreatePageFileMapping(Process, Address, SwapEntry);
    MmUnlockAddressSpace(AddressSpace);
    MmDeleteAllRmaps(Page, NULL, NULL);
    MmSetSavedSwapEntryPage(Page, 0);
@@ -255,7 +257,8 @@
    NTSTATUS Status;
    PMM_REGION Region;
    PMM_PAGEOP PageOp;
-
+   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
@@ -292,7 +295,7 @@
    /*
     * Get or create a page operation
     */
-   PageOp = MmGetPageOp(MemoryArea, AddressSpace->Process->UniqueProcessId,
+   PageOp = MmGetPageOp(MemoryArea, Process->UniqueProcessId,
                         (PVOID)PAGE_ROUND_DOWN(Address), NULL, 0,
                         MM_PAGEOP_PAGEIN, FALSE);
    if (PageOp == NULL)
@@ -380,7 +383,7 @@
    {
       SWAPENTRY SwapEntry;
 
-      MmDeletePageFileMapping(AddressSpace->Process, Address, &SwapEntry);
+      MmDeletePageFileMapping(Process, Address, &SwapEntry);
       Status = MmReadFromSwapPage(SwapEntry, Page);
       if (!NT_SUCCESS(Status))
       {
@@ -393,7 +396,7 @@
     * Set the page. If we fail because we are out of memory then
     * try again
     */
-   Status = MmCreateVirtualMapping(AddressSpace->Process,
+   Status = MmCreateVirtualMapping(Process,
                                    (PVOID)PAGE_ROUND_DOWN(Address),
                                    Region->Protect,
                                    &Page,
@@ -401,7 +404,7 @@
    while (Status == STATUS_NO_MEMORY)
    {
       MmUnlockAddressSpace(AddressSpace);
-      Status = MmCreateVirtualMapping(AddressSpace->Process,
+      Status = MmCreateVirtualMapping(Process,
                                       Address,
                                       Region->Protect,
                                       &Page,
@@ -418,7 +421,7 @@
    /*
     * Add the page to the process's working set
     */
-   MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAGE_ROUND_DOWN(Address));
+   MmInsertRmap(Page, Process, (PVOID)PAGE_ROUND_DOWN(Address));
 
    /*
     * Finish the operation
@@ -445,6 +448,8 @@
  * FUNCTION: Modify the attributes of a memory region
  */
 {
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
+    
    /*
     * If we are switching a previously committed region to reserved then
     * free any allocated pages within the region
@@ -457,19 +462,19 @@
       {
          PFN_TYPE Page;
 
-         if (MmIsPageSwapEntry(AddressSpace->Process,
+         if (MmIsPageSwapEntry(Process,
                                (char*)BaseAddress + (i * PAGE_SIZE)))
          {
             SWAPENTRY SwapEntry;
 
-            MmDeletePageFileMapping(AddressSpace->Process,
+            MmDeletePageFileMapping(Process,
                                     (char*)BaseAddress + (i * PAGE_SIZE),
                                     &SwapEntry);
             MmFreeSwapPage(SwapEntry);
          }
          else
          {
-            MmDeleteVirtualMapping(AddressSpace->Process,
+            MmDeleteVirtualMapping(Process,
                                    (char*)BaseAddress + (i*PAGE_SIZE),
                                    FALSE, NULL, &Page);
             if (Page != 0)
@@ -481,7 +486,7 @@
                   MmFreeSwapPage(SavedSwapEntry);
                   MmSetSavedSwapEntryPage(Page, 0);
                }
-               MmDeleteRmap(Page, AddressSpace->Process,
+               MmDeleteRmap(Page, Process,
                             (char*)BaseAddress + (i * PAGE_SIZE));
                MmReleasePageMemoryConsumer(MC_USER, Page);
             }
@@ -500,10 +505,10 @@
 
       for (i=0; i < PAGE_ROUND_UP(RegionSize)/PAGE_SIZE; i++)
       {
-         if (MmIsPagePresent(AddressSpace->Process,
+         if (MmIsPagePresent(Process,
                              (char*)BaseAddress + (i*PAGE_SIZE)))
          {
-            MmSetPageProtect(AddressSpace->Process,
+            MmSetPageProtect(Process,
                              (char*)BaseAddress + (i*PAGE_SIZE),
                              NewProtect);
          }

Modified: trunk/reactos/ntoskrnl/mm/aspace.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/aspace.c?rev=3…
==============================================================================
--- trunk/reactos/ntoskrnl/mm/aspace.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/aspace.c [iso-8859-1] Sun Jul 27 18:53:04 2008
@@ -43,13 +43,11 @@
 
     if (Process != NULL)
     {
-        AddressSpace->Process = Process;
         AddressSpace->Lock = (PEX_PUSH_LOCK)&Process->AddressCreationLock;
         ExInitializePushLock((PULONG_PTR)AddressSpace->Lock);        
     }
     else
     {
-        AddressSpace->Process = NULL;
         AddressSpace->Lock =
(PEX_PUSH_LOCK)&PsGetCurrentProcess()->AddressCreationLock;
         ExInitializePushLock((PULONG_PTR)AddressSpace->Lock);
     }

Modified: trunk/reactos/ntoskrnl/mm/marea.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/marea.c?rev=34…
==============================================================================
--- trunk/reactos/ntoskrnl/mm/marea.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/marea.c [iso-8859-1] Sun Jul 27 18:53:04 2008
@@ -470,8 +470,8 @@
    ULONG_PTR Length,
    ULONG_PTR Granularity)
 {
-   PVOID LowestAddress  = AddressSpace->Process ? MM_LOWEST_USER_ADDRESS :
MmSystemRangeStart;
-   PVOID HighestAddress = AddressSpace->Process ?
+   PVOID LowestAddress  = MmGetAddressSpaceOwner(AddressSpace) ? MM_LOWEST_USER_ADDRESS :
MmSystemRangeStart;
+   PVOID HighestAddress = MmGetAddressSpaceOwner(AddressSpace) ?
                           (PVOID)((ULONG_PTR)MmSystemRangeStart - 1) :
(PVOID)MAXULONG_PTR;
    PVOID AlignedAddress;
    PMEMORY_AREA Node;
@@ -548,8 +548,8 @@
    ULONG_PTR Length,
    ULONG_PTR Granularity)
 {
-   PVOID LowestAddress  = AddressSpace->Process ? MM_LOWEST_USER_ADDRESS :
MmSystemRangeStart;
-   PVOID HighestAddress = AddressSpace->Process ?
+   PVOID LowestAddress  = MmGetAddressSpaceOwner(AddressSpace) ? MM_LOWEST_USER_ADDRESS :
MmSystemRangeStart;
+   PVOID HighestAddress = MmGetAddressSpaceOwner(AddressSpace) ?
                           (PVOID)((ULONG_PTR)MmSystemRangeStart - 1) :
(PVOID)MAXULONG_PTR;
    PVOID AlignedAddress;
    PMEMORY_AREA Node;
@@ -648,8 +648,8 @@
 {
    PMEMORY_AREA Node = AddressSpace->MemoryAreaRoot;
    PMEMORY_AREA RightNeighbour = NULL;
-   PVOID LowestAddress  = AddressSpace->Process ? MM_LOWEST_USER_ADDRESS :
MmSystemRangeStart;
-   PVOID HighestAddress = AddressSpace->Process ?
+   PVOID LowestAddress  = MmGetAddressSpaceOwner(AddressSpace) ? MM_LOWEST_USER_ADDRESS :
MmSystemRangeStart;
+   PVOID HighestAddress = MmGetAddressSpaceOwner(AddressSpace) ?
                           (PVOID)((ULONG_PTR)MmSystemRangeStart - 1) :
(PVOID)MAXULONG_PTR;
 
    MmVerifyMemoryAreas(AddressSpace);
@@ -749,11 +749,12 @@
    ULONG_PTR Address;
    PVOID EndAddress;
    PEPROCESS CurrentProcess = PsGetCurrentProcess();
-
-   if (AddressSpace->Process != NULL &&
-       AddressSpace->Process != CurrentProcess)
-   {
-      KeAttachProcess(&AddressSpace->Process->Pcb);
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
+    
+   if (Process != NULL &&
+       Process != CurrentProcess)
+   {
+      KeAttachProcess(&Process->Pcb);
    }
 
    EndAddress = MM_ROUND_UP(MemoryArea->EndingAddress, PAGE_SIZE);
@@ -771,13 +772,13 @@
          SWAPENTRY SwapEntry = 0;
          PFN_TYPE Page = 0;
 
-         if (MmIsPageSwapEntry(AddressSpace->Process, (PVOID)Address))
+         if (MmIsPageSwapEntry(Process, (PVOID)Address))
          {
-            MmDeletePageFileMapping(AddressSpace->Process, (PVOID)Address,
&SwapEntry);
+            MmDeletePageFileMapping(Process, (PVOID)Address, &SwapEntry);
          }
          else
          {
-            MmDeleteVirtualMapping(AddressSpace->Process, (PVOID)Address, FALSE,
&Dirty, &Page);
+            MmDeleteVirtualMapping(Process, (PVOID)Address, FALSE, &Dirty,
&Page);
          }
          if (FreePage != NULL)
          {
@@ -787,8 +788,8 @@
       }
    }
 
-   if (AddressSpace->Process != NULL &&
-       AddressSpace->Process != CurrentProcess)
+   if (Process != NULL &&
+       Process != CurrentProcess)
    {
       KeDetachProcess();
    }
@@ -975,13 +976,13 @@
                          - (ULONG_PTR) MM_ROUND_DOWN(*BaseAddress, Granularity));
       *BaseAddress = MM_ROUND_DOWN(*BaseAddress, Granularity);
 
-      if (!AddressSpace->Process && *BaseAddress < MmSystemRangeStart)
+      if (!MmGetAddressSpaceOwner(AddressSpace) && *BaseAddress <
MmSystemRangeStart)
       {
          CHECKPOINT;
          return STATUS_ACCESS_VIOLATION;
       }
 
-      if (AddressSpace->Process &&
+      if (MmGetAddressSpaceOwner(AddressSpace) &&
           (ULONG_PTR)(*BaseAddress) + tmpLength > (ULONG_PTR)MmSystemRangeStart)
       {
          CHECKPOINT;

Modified: trunk/reactos/ntoskrnl/mm/section.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/section.c?rev=…
==============================================================================
--- trunk/reactos/ntoskrnl/mm/section.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/section.c [iso-8859-1] Sun Jul 27 18:53:04 2008
@@ -724,17 +724,18 @@
    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(AddressSpace->Process, Address))
+   if (MmIsPagePresent(Process, Address))
    {
       if (Locked)
       {
-         MmLockPage(MmGetPfnForProcess(AddressSpace->Process, Address));
+         MmLockPage(MmGetPfnForProcess(Process, Address));
       }
       return(STATUS_SUCCESS);
    }
@@ -825,10 +826,10 @@
        * If the completed fault was for another address space then set the
        * page in this one.
        */
-      if (!MmIsPagePresent(AddressSpace->Process, Address))
+      if (!MmIsPagePresent(Process, Address))
       {
          Entry = MmGetPageEntrySectionSegment(Segment, Offset);
-         HasSwapEntry = MmIsPageSwapEntry(AddressSpace->Process, (PVOID)PAddress);
+         HasSwapEntry = MmIsPageSwapEntry(Process, (PVOID)PAddress);
 
          if (PAGE_FROM_SSE(Entry) == 0 || HasSwapEntry)
          {
@@ -847,7 +848,7 @@
          /* FIXME: Should we call MmCreateVirtualMappingUnsafe if
           * (Section->AllocationAttributes & SEC_PHYSICALMEMORY) is true?
           */
-         Status = MmCreateVirtualMapping(AddressSpace->Process,
+         Status = MmCreateVirtualMapping(Process,
                                          Address,
                                          Attributes,
                                          &Page,
@@ -857,7 +858,7 @@
             DPRINT1("Unable to create virtual mapping\n");
             KEBUGCHECK(0);
          }
-         MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAddress);
+         MmInsertRmap(Page, Process, (PVOID)PAddress);
       }
       if (Locked)
       {
@@ -870,7 +871,7 @@
       return(STATUS_SUCCESS);
    }
 
-   HasSwapEntry = MmIsPageSwapEntry(AddressSpace->Process, (PVOID)PAddress);
+   HasSwapEntry = MmIsPageSwapEntry(Process, (PVOID)PAddress);
    if (HasSwapEntry)
    {
       /*
@@ -888,7 +889,7 @@
       }
 
       MmUnlockSectionSegment(Segment);
-      MmDeletePageFileMapping(AddressSpace->Process, (PVOID)PAddress,
&SwapEntry);
+      MmDeletePageFileMapping(Process, (PVOID)PAddress, &SwapEntry);
 
       MmUnlockAddressSpace(AddressSpace);
       Status = MmRequestPageMemoryConsumer(MC_USER, TRUE, &Page);
@@ -904,7 +905,7 @@
          KEBUGCHECK(0);
       }
       MmLockAddressSpace(AddressSpace);
-      Status = MmCreateVirtualMapping(AddressSpace->Process,
+      Status = MmCreateVirtualMapping(Process,
                                       Address,
                                       Region->Protect,
                                       &Page,
@@ -924,7 +925,7 @@
       /*
        * Add the page to the process's working set
        */
-      MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAddress);
+      MmInsertRmap(Page, Process, (PVOID)PAddress);
 
       /*
        * Finish the operation
@@ -949,7 +950,7 @@
        * Just map the desired physical page
        */
       Page = Offset >> PAGE_SHIFT;
-      Status = MmCreateVirtualMappingUnsafe(AddressSpace->Process,
+      Status = MmCreateVirtualMappingUnsafe(Process,
                                             Address,
                                             Region->Protect,
                                             &Page,
@@ -995,7 +996,7 @@
       {
          KEBUGCHECK(0);
       }
-      Status = MmCreateVirtualMapping(AddressSpace->Process,
+      Status = MmCreateVirtualMapping(Process,
                                       Address,
                                       Region->Protect,
                                       &Page,
@@ -1006,7 +1007,7 @@
          KEBUGCHECK(0);
          return(Status);
       }
-      MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAddress);
+      MmInsertRmap(Page, Process, (PVOID)PAddress);
       if (Locked)
       {
          MmLockPage(Page);
@@ -1095,7 +1096,7 @@
       MmSetPageEntrySectionSegment(Segment, Offset, Entry);
       MmUnlockSectionSegment(Segment);
 
-      Status = MmCreateVirtualMapping(AddressSpace->Process,
+      Status = MmCreateVirtualMapping(Process,
                                       Address,
                                       Attributes,
                                       &Page,
@@ -1105,7 +1106,7 @@
          DPRINT1("Unable to create virtual mapping\n");
          KEBUGCHECK(0);
       }
-      MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAddress);
+      MmInsertRmap(Page, Process, (PVOID)PAddress);
 
       if (Locked)
       {
@@ -1170,7 +1171,7 @@
        * Save the swap entry.
        */
       MmSetSavedSwapEntryPage(Page, SwapEntry);
-      Status = MmCreateVirtualMapping(AddressSpace->Process,
+      Status = MmCreateVirtualMapping(Process,
                                       Address,
                                       Region->Protect,
                                       &Page,
@@ -1180,7 +1181,7 @@
          DPRINT1("Unable to create virtual mapping\n");
          KEBUGCHECK(0);
       }
-      MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAddress);
+      MmInsertRmap(Page, Process, (PVOID)PAddress);
       if (Locked)
       {
          MmLockPage(Page);
@@ -1202,7 +1203,7 @@
       MmSharePageEntrySectionSegment(Segment, Offset);
       MmUnlockSectionSegment(Segment);
 
-      Status = MmCreateVirtualMapping(AddressSpace->Process,
+      Status = MmCreateVirtualMapping(Process,
                                       Address,
                                       Attributes,
                                       &Page,
@@ -1212,7 +1213,7 @@
          DPRINT1("Unable to create virtual mapping\n");
          KEBUGCHECK(0);
       }
-      MmInsertRmap(Page, AddressSpace->Process, (PVOID)PAddress);
+      MmInsertRmap(Page, Process, (PVOID)PAddress);
       if (Locked)
       {
          MmLockPage(Page);
@@ -1241,14 +1242,15 @@
    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(AddressSpace->Process, Address) ||
-         MmGetPageProtect(AddressSpace->Process, Address) & PAGE_READWRITE)
+   if (!MmIsPagePresent(Process, Address) ||
+         MmGetPageProtect(Process, Address) & PAGE_READWRITE)
    {
       DPRINT("Address 0x%.8X\n", Address);
       return(STATUS_SUCCESS);
@@ -1291,7 +1293,7 @@
        PFN_FROM_SSE(Entry) != OldPage)
    {
       /* This is a private page. We must only change the page protection. */
-      MmSetPageProtect(AddressSpace->Process, PAddress, Region->Protect);
+      MmSetPageProtect(Process, PAddress, Region->Protect);
       return(STATUS_SUCCESS);
    }
 
@@ -1358,12 +1360,12 @@
    /*
     * Delete the old entry.
     */
-   MmDeleteVirtualMapping(AddressSpace->Process, Address, FALSE, NULL, NULL);
+   MmDeleteVirtualMapping(Process, Address, FALSE, NULL, NULL);
 
    /*
     * Set the PTE to point to the new page
     */
-   Status = MmCreateVirtualMapping(AddressSpace->Process,
+   Status = MmCreateVirtualMapping(Process,
                                    Address,
                                    Region->Protect,
                                    &NewPage,
@@ -1388,8 +1390,8 @@
    /*
     * Unshare the old page.
     */
-   MmDeleteRmap(OldPage, AddressSpace->Process, PAddress);
-   MmInsertRmap(NewPage, AddressSpace->Process, PAddress);
+   MmDeleteRmap(OldPage, Process, PAddress);
+   MmInsertRmap(NewPage, Process, PAddress);
    MmLockSectionSegment(Segment);
    MmUnsharePageEntrySectionSegment(Section, Segment, Offset, FALSE, FALSE);
    MmUnlockSectionSegment(Segment);
@@ -1462,7 +1464,8 @@
    PBCB Bcb = NULL;
    BOOLEAN DirectMapped;
    BOOLEAN IsImageSection;
-
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
+    
    Address = (PVOID)PAGE_ROUND_DOWN(Address);
 
    /*
@@ -1505,7 +1508,7 @@
    {
       DPRINT1("Trying to page out from physical memory section address 0x%X "
               "process %d\n", Address,
-              AddressSpace->Process ? AddressSpace->Process->UniqueProcessId :
0);
+              Process ? Process->UniqueProcessId : 0);
       KEBUGCHECK(0);
    }
 
@@ -1513,13 +1516,13 @@
     * Get the section segment entry and the physical address.
     */
    Entry = MmGetPageEntrySectionSegment(Context.Segment, Context.Offset);
-   if (!MmIsPagePresent(AddressSpace->Process, Address))
+   if (!MmIsPagePresent(Process, Address))
    {
       DPRINT1("Trying to page out not-present page at (%d,0x%.8X).\n",
-              AddressSpace->Process ? AddressSpace->Process->UniqueProcessId :
0, Address);
+              Process ? Process->UniqueProcessId : 0, Address);
       KEBUGCHECK(0);
    }
-   Page = MmGetPfnForProcess(AddressSpace->Process, Address);
+   Page = MmGetPfnForProcess(Process, Address);
    SwapEntry = MmGetSavedSwapEntryPage(Page);
 
    /*
@@ -1650,7 +1653,7 @@
    {
       MmSetSavedSwapEntryPage(Page, 0);
       MmLockAddressSpace(AddressSpace);
-      Status = MmCreatePageFileMapping(AddressSpace->Process,
+      Status = MmCreatePageFileMapping(Process,
                                        Address,
                                        SwapEntry);
       MmUnlockAddressSpace(AddressSpace);
@@ -1679,14 +1682,14 @@
           */
          if (Context.Private)
          {
-            Status = MmCreateVirtualMapping(AddressSpace->Process,
+            Status = MmCreateVirtualMapping(Process,
                                             Address,
                                             MemoryArea->Protect,
                                             &Page,
                                             1);
-            MmSetDirtyPage(AddressSpace->Process, Address);
+            MmSetDirtyPage(Process, Address);
             MmInsertRmap(Page,
-                         AddressSpace->Process,
+                         Process,
                          Address);
          }
          else
@@ -1696,14 +1699,14 @@
              * 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(AddressSpace->Process,
+            Status = MmCreateVirtualMapping(Process,
                                             Address,
                                             MemoryArea->Protect,
                                             &Page,
                                             1);
-            MmSetDirtyPage(AddressSpace->Process, Address);
+            MmSetDirtyPage(Process, Address);
             MmInsertRmap(Page,
-                         AddressSpace->Process,
+                         Process,
                          Address);
             Entry = MAKE_SSE(Page << PAGE_SHIFT, 1);
             MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, Entry);
@@ -1730,26 +1733,26 @@
       MmLockAddressSpace(AddressSpace);
       if (Context.Private)
       {
-         Status = MmCreateVirtualMapping(AddressSpace->Process,
+         Status = MmCreateVirtualMapping(Process,
                                          Address,
                                          MemoryArea->Protect,
                                          &Page,
                                          1);
-         MmSetDirtyPage(AddressSpace->Process, Address);
+         MmSetDirtyPage(Process, Address);
          MmInsertRmap(Page,
-                      AddressSpace->Process,
+                      Process,
                       Address);
       }
       else
       {
-         Status = MmCreateVirtualMapping(AddressSpace->Process,
+         Status = MmCreateVirtualMapping(Process,
                                          Address,
                                          MemoryArea->Protect,
                                          &Page,
                                          1);
-         MmSetDirtyPage(AddressSpace->Process, Address);
+         MmSetDirtyPage(Process, Address);
          MmInsertRmap(Page,
-                      AddressSpace->Process,
+                      Process,
                       Address);
          Entry = MAKE_SSE(Page << PAGE_SHIFT, 1);
          MmSetPageEntrySectionSegment(Context.Segment, Context.Offset, Entry);
@@ -1778,7 +1781,7 @@
    if (Context.Private)
    {
       MmLockAddressSpace(AddressSpace);
-      Status = MmCreatePageFileMapping(AddressSpace->Process,
+      Status = MmCreatePageFileMapping(Process,
                                        Address,
                                        SwapEntry);
       MmUnlockAddressSpace(AddressSpace);
@@ -1817,6 +1820,7 @@
    PBCB Bcb = NULL;
    BOOLEAN DirectMapped;
    BOOLEAN IsImageSection;
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
 
    Address = (PVOID)PAGE_ROUND_DOWN(Address);
 
@@ -1857,7 +1861,7 @@
    {
       DPRINT1("Trying to write back page from physical memory mapped at %X "
               "process %d\n", Address,
-              AddressSpace->Process ? AddressSpace->Process->UniqueProcessId :
0);
+              Process ? Process->UniqueProcessId : 0);
       KEBUGCHECK(0);
    }
 
@@ -1865,13 +1869,13 @@
     * Get the section segment entry and the physical address.
     */
    Entry = MmGetPageEntrySectionSegment(Segment, Offset);
-   if (!MmIsPagePresent(AddressSpace->Process, Address))
+   if (!MmIsPagePresent(Process, Address))
    {
       DPRINT1("Trying to page out not-present page at (%d,0x%.8X).\n",
-              AddressSpace->Process ? AddressSpace->Process->UniqueProcessId :
0, Address);
+              Process ? Process->UniqueProcessId : 0, Address);
       KEBUGCHECK(0);
    }
-   Page = MmGetPfnForProcess(AddressSpace->Process, Address);
+   Page = MmGetPfnForProcess(Process, Address);
    SwapEntry = MmGetSavedSwapEntryPage(Page);
 
    /*
@@ -1958,6 +1962,7 @@
    PMM_SECTION_SEGMENT Segment;
    BOOLEAN DoCOW = FALSE;
    ULONG i;
+   PEPROCESS Process = MmGetAddressSpaceOwner(AddressSpace);
 
    MemoryArea = MmLocateMemoryAreaByAddress(AddressSpace, BaseAddress);
    Segment = MemoryArea->Data.SectionData.Segment;
@@ -1979,7 +1984,7 @@
           * If we doing COW for this segment then check if the page is
           * already private.
           */
-         if (DoCOW && MmIsPagePresent(AddressSpace->Process, Address))
+         if (DoCOW && MmIsPagePresent(Process, Address))
          {
             ULONG Offset;
             ULONG Entry;
@@ -1988,7 +1993,7 @@
             Offset = (ULONG_PTR)Address - (ULONG_PTR)MemoryArea->StartingAddress
                      + MemoryArea->Data.SectionData.ViewOffset;
             Entry = MmGetPageEntrySectionSegment(Segment, Offset);
-            Page = MmGetPfnForProcess(AddressSpace->Process, Address);
+            Page = MmGetPfnForProcess(Process, Address);
 
             Protect = PAGE_READONLY;
             if (Segment->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA ||
@@ -1999,9 +2004,9 @@
             }
          }
 
-         if (MmIsPagePresent(AddressSpace->Process, Address))
+         if (MmIsPagePresent(Process, Address))
          {
-            MmSetPageProtect(AddressSpace->Process, Address,
+            MmSetPageProtect(Process, Address,
                              Protect);
          }
       }
@@ -3836,8 +3841,10 @@
    PROS_SECTION_OBJECT Section;
    PMM_SECTION_SEGMENT Segment;
    PMADDRESS_SPACE AddressSpace;
+   PEPROCESS Process;
 
    AddressSpace = (PMADDRESS_SPACE)Context;
+   Process = MmGetAddressSpaceOwner(AddressSpace);
 
    Address = (PVOID)PAGE_ROUND_DOWN(Address);
 
@@ -3918,12 +3925,12 @@
             MmFreeSwapPage(SavedSwapEntry);
             MmSetSavedSwapEntryPage(Page, 0);
          }
-         MmDeleteRmap(Page, AddressSpace->Process, Address);
+         MmDeleteRmap(Page, Process, Address);
          MmReleasePageMemoryConsumer(MC_USER, Page);
       }
       else
       {
-         MmDeleteRmap(Page, AddressSpace->Process, Address);
+         MmDeleteRmap(Page, Process, Address);
          MmUnsharePageEntrySectionSegment(Section, Segment, Offset, Dirty, FALSE);
       }
    }