[sir_richard] 48918: [NTOS]: One last fix to the zero page thread before we move to ARM3: use MiRemoveAnyPage instead of dangerous MiRemoveHeadList. The code works on the assumption (validated by W...

Author: sir_richard
Date: Tue Sep 28 14:29:37 2010
New Revision: 48918

URL: http://svn.reactos.org/svn/reactos?rev=48918&view=rev
Log:
[NTOS]: One last fix to the zero page thread before we move to ARM3: use MiRemoveAnyPage
instead of dangerous MiRemoveHeadList. The code works on the assumption (validated by
Windows through a bug check) that MiRemoveAnyPage always returns the first free page, and
we also manually grab the first free page, and compare this is true. Nice way to detect
PFN database corruption.
[NTOS]: Fix MiInsertZeroAtBack to increment the MmAvailablePage count, since
MiRemoveAnyPage decrements it (MiRemoveHeadList did not).

Modified:
    trunk/reactos/ntoskrnl/mm/ARM3/pfnlist.c
    trunk/reactos/ntoskrnl/mm/freelist.c

Modified: trunk/reactos/ntoskrnl/mm/ARM3/pfnlist.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/ARM3/pfnlist.c…
==============================================================================
--- trunk/reactos/ntoskrnl/mm/ARM3/pfnlist.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/ARM3/pfnlist.c [iso-8859-1] Tue Sep 28 14:29:37 2010
@@ -156,8 +156,8 @@
     /* Update the page location */
     Pfn1->u3.e1.PageLocation = ZeroedPageList;
 
-    /* FIXME: NOT YET Due to caller semantics: Update the available page count */
-    //MmAvailablePages++;
+    /* Update the available page count */
+    MmAvailablePages++;
 
     /* Check if we've reached the configured low memory threshold */
     if (MmAvailablePages == MmLowMemoryThreshold)

Modified: trunk/reactos/ntoskrnl/mm/freelist.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/freelist.c?rev…
==============================================================================
--- trunk/reactos/ntoskrnl/mm/freelist.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/mm/freelist.c [iso-8859-1] Tue Sep 28 14:29:37 2010
@@ -631,8 +631,8 @@
 {
    NTSTATUS Status;
    KIRQL oldIrql;
-   PPHYSICAL_PAGE PageDescriptor;
-   PFN_NUMBER Pfn;
+   PMMPFN Pfn1;
+   PFN_NUMBER PageIndex, FreePage;
    ULONG Count;
    PVOID ZeroAddress;
 
@@ -660,21 +660,30 @@
       oldIrql = KeAcquireQueuedSpinLock(LockQueuePfnLock);
       while (MmFreePageListHead.Total)
       {
-         PageDescriptor = MiRemoveHeadList(&MmFreePageListHead);
-         Pfn = MiGetPfnEntryIndex(PageDescriptor);
-         KeReleaseQueuedSpinLock(LockQueuePfnLock, oldIrql);
-         
-         PageDescriptor->u1.Flink = LIST_HEAD;
-         ZeroAddress = MiMapPagesToZeroInHyperSpace(PageDescriptor, 1);
-         ASSERT(ZeroAddress);
-         RtlZeroMemory(ZeroAddress, PAGE_SIZE);
-         MiUnmapPagesInZeroSpace(ZeroAddress, 1);
-
-         oldIrql = KeAcquireQueuedSpinLock(LockQueuePfnLock);
-        
-         MiInsertZeroListAtBack(Pfn);
-         Count++;
-
+          PageIndex = MmFreePageListHead.Flink;
+          Pfn1 = MiGetPfnEntry(PageIndex);
+          FreePage = MiRemoveAnyPage(0); // FIXME: Use real color
+          if (FreePage != PageIndex)
+          {
+              KeBugCheckEx(PFN_LIST_CORRUPT,
+                           0x8F,
+                           FreePage,
+                           PageIndex,
+                           0);
+          }
+          
+          Pfn1->u1.Flink = LIST_HEAD;
+          KeReleaseQueuedSpinLock(LockQueuePfnLock, oldIrql);
+  
+          ZeroAddress = MiMapPagesToZeroInHyperSpace(Pfn1, 1);
+          ASSERT(ZeroAddress);
+          RtlZeroMemory(ZeroAddress, PAGE_SIZE);
+          MiUnmapPagesInZeroSpace(ZeroAddress, 1);
+                   
+          oldIrql = KeAcquireQueuedSpinLock(LockQueuePfnLock);
+        
+          MiInsertZeroListAtBack(PageIndex);
+          Count++;
       }
       DPRINT("Zeroed %d pages.\n", Count);
       KeResetEvent(&ZeroPageThreadEvent);