--- /dev/null	2018-04-03 12:55:20.301839954 +0200
+++ new/src/hotspot/share/gc/z/zVirtualMemory.cpp	2018-06-08 19:46:47.770917018 +0200
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "gc/z/zGlobals.hpp"
+#include "gc/z/zVirtualMemory.inline.hpp"
+#include "services/memTracker.hpp"
+
+ZVirtualMemoryManager::ZVirtualMemoryManager() :
+    _manager(),
+    _initialized(false) {
+  // Reserve address space
+  if (!reserve(ZAddressSpaceStart, ZAddressSpaceSize)) {
+    return;
+  }
+
+  // Make the complete address view free
+  _manager.free(0, ZAddressOffsetMax);
+
+  // Register address space with native memory tracker
+  nmt_reserve(ZAddressSpaceStart, ZAddressSpaceSize);
+
+  // Successfully initialized
+  _initialized = true;
+}
+
+void ZVirtualMemoryManager::nmt_reserve(uintptr_t start, size_t size) {
+  MemTracker::record_virtual_memory_reserve((void*)start, size, CALLER_PC);
+  MemTracker::record_virtual_memory_type((void*)start, mtJavaHeap);
+}
+
+bool ZVirtualMemoryManager::is_initialized() const {
+  return _initialized;
+}
+
+ZVirtualMemory ZVirtualMemoryManager::alloc(size_t size, bool alloc_from_front) {
+  uintptr_t start;
+
+  if (alloc_from_front || size <= ZPageSizeSmall) {
+    // Small page
+    start = _manager.alloc_from_front(size);
+  } else {
+    // Medium/Large page
+    start = _manager.alloc_from_back(size);
+  }
+
+  return ZVirtualMemory(start, size);
+}
+
+void ZVirtualMemoryManager::free(ZVirtualMemory vmem) {
+  _manager.free(vmem.start(), vmem.size());
+}