[tfaber] 74358: [NTOS:CC] - Respect the TruncateSize parameter in CcUninitializeCacheMap. Avoids "freeing dirty VACB" messages for cache views beyond the end of the file. CORE-12893 #resolve

Author: tfaber
Date: Mon Apr 17 18:37:12 2017
New Revision: 74358

URL: http://svn.reactos.org/svn/reactos?rev=74358&view=rev
Log:
[NTOS:CC]
- Respect the TruncateSize parameter in CcUninitializeCacheMap. Avoids "freeing dirty
VACB" messages for cache views beyond the end of the file.
CORE-12893 #resolve

Modified:
    trunk/reactos/ntoskrnl/cc/fs.c

Modified: trunk/reactos/ntoskrnl/cc/fs.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/cc/fs.c?rev=74358…
==============================================================================
--- trunk/reactos/ntoskrnl/cc/fs.c	[iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/cc/fs.c	[iso-8859-1] Mon Apr 17 18:37:12 2017
@@ -286,13 +286,34 @@
     IN PCACHE_UNINITIALIZE_EVENT UninitializeCompleteEvent OPTIONAL)
 {
     NTSTATUS Status;
+    PROS_SHARED_CACHE_MAP SharedCacheMap;
+    KIRQL OldIrql;
 
     CCTRACE(CC_API_DEBUG, "FileObject=%p TruncateSize=%p
UninitializeCompleteEvent=%p\n",
         FileObject, TruncateSize, UninitializeCompleteEvent);
 
+    if (TruncateSize != NULL &&
+        FileObject->SectionObjectPointer != NULL &&
+        FileObject->SectionObjectPointer->SharedCacheMap != NULL)
+    {
+        SharedCacheMap = FileObject->SectionObjectPointer->SharedCacheMap;
+        KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &OldIrql);
+        if (SharedCacheMap->FileSize.QuadPart > TruncateSize->QuadPart)
+        {
+            SharedCacheMap->FileSize = *TruncateSize;
+        }
+        KeReleaseSpinLock(&SharedCacheMap->CacheMapLock, OldIrql);
+        CcPurgeCacheSection(FileObject->SectionObjectPointer,
+                            TruncateSize,
+                            0,
+                            FALSE);
+    }
+
     Status = CcRosReleaseFileCache(FileObject);
     if (UninitializeCompleteEvent)
+    {
         KeSetEvent(&UninitializeCompleteEvent->Event, IO_NO_INCREMENT, FALSE);
+    }
     return NT_SUCCESS(Status);
 }