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diff --git a/standalone/mem_map_base.h b/standalone/mem_map_base.h
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+//===-- mem_map_base.h ------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SCUDO_MEM_MAP_BASE_H_
+#define SCUDO_MEM_MAP_BASE_H_
+
+#include "common.h"
+
+namespace scudo {
+
+// In Scudo, every memory operation will be fulfilled through a
+// platform-specific `MemMap` instance. The essential APIs are listed in the
+// `MemMapBase` below. This is implemented in CRTP, so for each implementation,
+// it has to implement all of the 'Impl' named functions.
+template <class Derived> class MemMapBase {
+public:
+  constexpr MemMapBase() = default;
+
+  // This is used to map a new set of contiguous pages. Note that the `Addr` is
+  // only a suggestion to the system.
+  bool map(uptr Addr, uptr Size, const char *Name, uptr Flags = 0) {
+    DCHECK(!isAllocated());
+    return invokeImpl(&Derived::mapImpl, Addr, Size, Name, Flags);
+  }
+
+  // This is used to unmap partial/full pages from the beginning or the end.
+  // I.e., the result pages are expected to be still contiguous.
+  void unmap(uptr Addr, uptr Size) {
+    DCHECK(isAllocated());
+    DCHECK((Addr == getBase()) || (Addr + Size == getBase() + getCapacity()));
+    invokeImpl(&Derived::unmapImpl, Addr, Size);
+  }
+
+  // This is used to remap a mapped range (either from map() or dispatched from
+  // ReservedMemory). For example, we have reserved several pages and then we
+  // want to remap them with different accessibility.
+  bool remap(uptr Addr, uptr Size, const char *Name, uptr Flags = 0) {
+    DCHECK(isAllocated());
+    DCHECK((Addr >= getBase()) || (Addr + Size <= getBase() + getCapacity()));
+    return invokeImpl(&Derived::remapImpl, Addr, Size, Name, Flags);
+  }
+
+  // This is used to update the pages' access permission. For example, mark
+  // pages as no read/write permission.
+  void setMemoryPermission(uptr Addr, uptr Size, uptr Flags) {
+    DCHECK(isAllocated());
+    DCHECK((Addr >= getBase()) || (Addr + Size <= getBase() + getCapacity()));
+    return static_cast<Derived *>(this)->setMemoryPermissionImpl(Addr, Size,
+                                                                 Flags);
+  }
+
+  // Suggest releasing a set of contiguous physical pages back to the OS. Note
+  // that only physical pages are supposed to be released. Any release of
+  // virtual pages may lead to undefined behavior.
+  void releasePagesToOS(uptr From, uptr Size) {
+    DCHECK(isAllocated());
+    DCHECK((From >= getBase()) || (From + Size <= getBase() + getCapacity()));
+    invokeImpl(&Derived::releasePagesToOSImpl, From, Size);
+  }
+  // This is similar to the above one except that any subsequent access to the
+  // released pages will return with zero-filled pages.
+  void releaseAndZeroPagesToOS(uptr From, uptr Size) {
+    DCHECK(isAllocated());
+    DCHECK((From >= getBase()) || (From + Size <= getBase() + getCapacity()));
+    invokeImpl(&Derived::releaseAndZeroPagesToOSImpl, From, Size);
+  }
+
+  uptr getBase() { return invokeImpl(&Derived::getBaseImpl); }
+  uptr getCapacity() { return invokeImpl(&Derived::getCapacityImpl); }
+
+  bool isAllocated() { return getBase() != 0U; }
+
+protected:
+  template <typename R, typename... Args>
+  R invokeImpl(R (Derived::*MemFn)(Args...), Args... args) {
+    return (static_cast<Derived *>(this)->*MemFn)(args...);
+  }
+};
+
+// `ReservedMemory` is a special memory handle which can be viewed as a page
+// allocator. `ReservedMemory` will reserve a contiguous pages and the later
+// page request can be fulfilled at the designated address. This is used when
+// we want to ensure the virtual address of the MemMap will be in a known range.
+// This is implemented in CRTP, so for each
+// implementation, it has to implement all of the 'Impl' named functions.
+template <class Derived, typename MemMapTy> class ReservedMemory {
+public:
+  using MemMapT = MemMapTy;
+  constexpr ReservedMemory() = default;
+
+  // Reserve a chunk of memory at a suggested address.
+  bool create(uptr Addr, uptr Size, const char *Name, uptr Flags = 0) {
+    DCHECK(!isCreated());
+    return invokeImpl(&Derived::createImpl, Addr, Size, Name, Flags);
+  }
+
+  // Release the entire reserved memory.
+  void release() {
+    DCHECK(isCreated());
+    invokeImpl(&Derived::releaseImpl);
+  }
+
+  // Dispatch a sub-range of reserved memory. Note that any fragmentation of
+  // the reserved pages is managed by each implementation.
+  MemMapT dispatch(uptr Addr, uptr Size) {
+    DCHECK(isCreated());
+    DCHECK((Addr >= getBase()) || (Addr + Size <= getBase() + getCapacity()));
+    return invokeImpl(&Derived::dispatchImpl, Addr, Size);
+  }
+
+  uptr getBase() { return invokeImpl(&Derived::getBaseImpl); }
+  uptr getCapacity() { return invokeImpl(&Derived::getCapacityImpl); }
+
+  bool isCreated() { return getBase() != 0U; }
+
+protected:
+  template <typename R, typename... Args>
+  R invokeImpl(R (Derived::*MemFn)(Args...), Args... args) {
+    return (static_cast<Derived *>(this)->*MemFn)(args...);
+  }
+};
+
+} // namespace scudo
+
+#endif // SCUDO_MEM_MAP_BASE_H_