[arty] 44278: Fix bugs: io - weren't at DISPATCH_LEVEL when using hyperspace. data - simplify page free and writeback in data sections.

Author: arty
Date: Tue Nov 24 01:48:06 2009
New Revision: 44278

URL: http://svn.reactos.org/svn/reactos?rev=44278&view=rev
Log:
Fix bugs:
io - weren't at DISPATCH_LEVEL when using hyperspace.
data - simplify page free and writeback in data sections.

Modified:
    branches/arty-newcc/ntoskrnl/mm/section/data.c
    branches/arty-newcc/ntoskrnl/mm/section/io.c

Modified: branches/arty-newcc/ntoskrnl/mm/section/data.c
URL:
http://svn.reactos.org/svn/reactos/branches/arty-newcc/ntoskrnl/mm/section/…
==============================================================================
--- branches/arty-newcc/ntoskrnl/mm/section/data.c [iso-8859-1] (original)
+++ branches/arty-newcc/ntoskrnl/mm/section/data.c [iso-8859-1] Tue Nov 24 01:48:06 2009
@@ -2216,8 +2216,6 @@
    PFILE_OBJECT FileObject;
    LARGE_INTEGER Offset;
    SWAPENTRY SavedSwapEntry;
-   PMM_PAGEOP PageOp;
-   NTSTATUS Status;
    PROS_SECTION_OBJECT Section;
    PMM_SECTION_SEGMENT Segment;
    PMMSUPPORT AddressSpace;
@@ -2234,26 +2232,6 @@
    Section = MemoryArea->Data.SectionData.Section;
    Segment = MemoryArea->Data.SectionData.Segment;
    FileObject = Section->FileObject;
-
-   PageOp = MmCheckForPageOp(MemoryArea, NULL, NULL, Segment, Offset.QuadPart);
-
-   while (PageOp)
-   {
-      MmUnlockSectionSegment(Segment);
-      MmUnlockAddressSpace(AddressSpace);
-
-      Status = MmspWaitForPageOpCompletionEvent(PageOp);
-      if (Status != STATUS_SUCCESS)
-      {
-         DPRINT1("Failed to wait for page op, status = %x\n", Status);
-         ASSERT(FALSE);
-      }
-
-      MmLockAddressSpace(AddressSpace);
-      MmLockSectionSegment(Segment);
-      MmspCompleteAndReleasePageOp(PageOp);
-      PageOp = MmCheckForPageOp(MemoryArea, NULL, NULL, Segment, Offset.QuadPart);
-   }
 
    Entry = MiGetPageEntrySectionSegment(Segment, &Offset);
 
@@ -2263,8 +2241,17 @@
     */
    if (Page == PFN_FROM_SSE(Entry) && Dirty)
    {
-	   DPRINT("Writing back dirty section page %08x%08x\n", Offset.u.HighPart,
Offset.u.LowPart);
-	   Status = MiWriteBackPage(FileObject, &Offset, PAGE_SIZE, Page);
+	   MmReferencePage(Page);
+	   MmUnlockSectionSegment(Segment);
+	   MiWriteBackPage(FileObject, &Offset, PAGE_SIZE, Page);
+	   MmLockSectionSegment(Segment);
+	   MmDereferencePage(Page);
+	   Entry = MiGetPageEntrySectionSegment(Segment, &Offset);
+	   if (Page != PFN_FROM_SSE(Entry)) 
+	   {
+		   // Somebody else freed the page while we were unlocked
+		   return;
+	   }
    }
 
    if (SwapEntry != 0)

Modified: branches/arty-newcc/ntoskrnl/mm/section/io.c
URL:
http://svn.reactos.org/svn/reactos/branches/arty-newcc/ntoskrnl/mm/section/…
==============================================================================
--- branches/arty-newcc/ntoskrnl/mm/section/io.c [iso-8859-1] (original)
+++ branches/arty-newcc/ntoskrnl/mm/section/io.c [iso-8859-1] Tue Nov 24 01:48:06 2009
@@ -431,13 +431,16 @@
 	NTSTATUS Status;
 	PVOID Hyperspace;
 	IO_STATUS_BLOCK Iosb;
+	KIRQL OldIrql;
 	PVOID PageBuffer = ExAllocatePool(NonPagedPool, PAGE_SIZE);
 
 	if (!PageBuffer) return STATUS_NO_MEMORY;
 
+	OldIrql = KfRaiseIrql(DISPATCH_LEVEL);
 	Hyperspace = MmCreateHyperspaceMapping(Page);
 	RtlCopyMemory(PageBuffer, Hyperspace, PAGE_SIZE);
 	MmDeleteHyperspaceMapping(Hyperspace);
+	KfLowerIrql(OldIrql);
 
 	DPRINT("MiWriteBackPage(%wZ,%08x%08x)\n", &FileObject->FileName,
FileOffset->u.HighPart, FileOffset->u.LowPart);
 	Status = MiSimpleWrite