[NTOSKRNL] CcPurgeCacheSection: Check if SharedCacheMap is NULL. Change suggested...

[reactos.git] / reactos / ntoskrnl / cc / fs.c

diff --git a/reactos/ntoskrnl/cc/fs.c b/reactos/ntoskrnl/cc/fs.c
index d0f3a38..4ecd553 100644 (file)
--- a/reactos/ntoskrnl/cc/fs.c
+++ b/reactos/ntoskrnl/cc/fs.c
@@ -153,6 +153,8 @@ CcPurgeCacheSection (
     }
 
     SharedCacheMap = SectionObjectPointer->SharedCacheMap;
+    if (!SharedCacheMap)
+        return FALSE;
 
     StartOffset = FileOffset != NULL ? FileOffset->QuadPart : 0;
     if (Length == 0 || FileOffset == NULL)
@@ -286,13 +288,34 @@ CcUninitializeCacheMap (
     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);
 }