[NTOSKRNL] Misc fixes to Cc:

- CcUnpinDataForThread() only release VACB when the last BCB reference is gone. This avoids having a valid BCB with an invalid VACB
- CcRosMarkDirtyVacb() will only accept non-dirty VACB now. This avoids a major bug where a an already dirty VACB was over-dereferenced
- Thanks to previous point, simplify CcRosUnmapVacb(), CcRosReleaseVacb() implementation
- And only set VACB dirty once in CcSetDirtyPinnedData()
- Add a few sanity checks

With that I can again install ReactOS with 128MB RAM :-).

CORE-14263
CORE-14268

ntoskrnl/cc/pin.c

@@ -247,8 +247,11 @@ CcSetDirtyPinnedData (
         Bcb, Lsn);
 
     iBcb->Dirty = TRUE;
+    if (!iBcb->Vacb->Dirty)
+    {
         CcRosMarkDirtyVacb(iBcb->Vacb);
     }
+}
 
 
 /*
@@ -284,14 +287,14 @@ CcUnpinDataForThread (
         iBcb->Vacb->PinCount--;
     }
 
+    if (--iBcb->RefCount == 0)
+    {
         CcRosReleaseVacb(iBcb->Vacb->SharedCacheMap,
                          iBcb->Vacb,
                          TRUE,
                          iBcb->Dirty,
                          FALSE);
 
-    if (--iBcb->RefCount == 0)
-    {
         ExDeleteResourceLite(&iBcb->Lock);
         ExFreeToNPagedLookasideList(&iBcbLookasideList, iBcb);
     }

ntoskrnl/cc/view.c

@@ -99,6 +99,7 @@ static void CcRosVacbIncRefCount_(PROS_VACB vacb, const char* file, int line)
 static void CcRosVacbDecRefCount_(PROS_VACB vacb, const char* file, int line)
 {
     --vacb->ReferenceCount;
+    ASSERT(!(vacb->ReferenceCount == 0 && vacb->Dirty));
     if (vacb->SharedCacheMap->Trace)
     {
         DbgPrint("(%s:%i) VACB %p --RefCount=%lu, Dirty %u, PageOut %lu\n",
@@ -518,8 +519,6 @@ CcRosReleaseVacb (
     BOOLEAN Dirty,
     BOOLEAN Mapped)
 {
-    BOOLEAN WasDirty;
-
     ASSERT(SharedCacheMap);
 
     DPRINT("CcRosReleaseVacb(SharedCacheMap 0x%p, Vacb 0x%p, Valid %u)\n",
@@ -527,18 +526,10 @@ CcRosReleaseVacb (
 
     Vacb->Valid = Valid;
 
-    WasDirty = FALSE;
+    if (Dirty && !Vacb->Dirty)
-    if (Dirty)
-    {
-        if (!Vacb->Dirty)
     {
         CcRosMarkDirtyVacb(Vacb);
     }
-        else
-        {
-            WasDirty = TRUE;
-        }
-    }
 
     if (Mapped)
     {
@@ -549,10 +540,6 @@ CcRosReleaseVacb (
     {
         CcRosVacbIncRefCount(Vacb);
     }
-    if (!WasDirty && Vacb->Dirty)
-    {
-        CcRosVacbIncRefCount(Vacb);
-    }
 
     CcRosReleaseVacbLock(Vacb);
 
@@ -618,16 +605,12 @@ CcRosMarkDirtyVacb (
     KeAcquireGuardedMutex(&ViewLock);
     KeAcquireSpinLock(&SharedCacheMap->CacheMapLock, &oldIrql);
 
-    if (!Vacb->Dirty)
+    ASSERT(!Vacb->Dirty);
-    {
+
     InsertTailList(&DirtyVacbListHead, &Vacb->DirtyVacbListEntry);
     CcTotalDirtyPages += VACB_MAPPING_GRANULARITY / PAGE_SIZE;
     Vacb->SharedCacheMap->DirtyPages += VACB_MAPPING_GRANULARITY / PAGE_SIZE;
-    }
+    CcRosVacbIncRefCount(Vacb);
-    else
-    {
-        CcRosVacbDecRefCount(Vacb);
-    }
 
     /* Move to the tail of the LRU list */
     RemoveEntryList(&Vacb->VacbLruListEntry);
@@ -658,7 +641,10 @@ CcRosMarkDirtyFile (
         KeBugCheck(CACHE_MANAGER);
     }
 
+    if (!Vacb->Dirty)
+    {
         CcRosMarkDirtyVacb(Vacb);
+    }
 
     CcRosReleaseVacbLock(Vacb);
 
@@ -673,7 +659,6 @@ CcRosUnmapVacb (
     BOOLEAN NowDirty)
 {
     PROS_VACB Vacb;
-    BOOLEAN WasDirty;
 
     ASSERT(SharedCacheMap);
 
@@ -686,26 +671,14 @@ CcRosUnmapVacb (
         return STATUS_UNSUCCESSFUL;
     }
 
-    WasDirty = FALSE;
+    if (NowDirty && !Vacb->Dirty)
-    if (NowDirty)
-    {
-        if (!Vacb->Dirty)
     {
         CcRosMarkDirtyVacb(Vacb);
     }
-        else
-        {
-            WasDirty = TRUE;
-        }
-    }
 
     Vacb->MappedCount--;
 
     CcRosVacbDecRefCount(Vacb);
-    if (!WasDirty && NowDirty)
-    {
-        CcRosVacbIncRefCount(Vacb);
-    }
     if (Vacb->MappedCount == 0)
     {
         CcRosVacbDecRefCount(Vacb);