chromium/v8/src/base/emulated-virtual-address-subspace.h

// Copyright 2021 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef V8_BASE_EMULATED_VIRTUAL_ADDRESS_SUBSPACE_H_
#define V8_BASE_EMULATED_VIRTUAL_ADDRESS_SUBSPACE_H_

#include "include/v8-platform.h"
#include "src/base/base-export.h"
#include "src/base/compiler-specific.h"
#include "src/base/platform/mutex.h"
#include "src/base/region-allocator.h"
#include "src/base/virtual-address-space.h"

namespace v8 {
namespace base {

/**
 * Emulates a virtual address subspace.
 *
 * This class is (optionally) backed by a page allocation and emulates a virtual
 * address space that is potentially larger than that mapping. It generally
 * first attempts to satisfy page allocation requests from its backing mapping,
 * but will also attempt to obtain new page mappings inside the unmapped space
 * through page allocation hints if necessary.
 *
 * Caveat: an emulated subspace violates the invariant that page allocations in
 * an address space will never end up inside a child space and so does not
 * provide the same security gurarantees.
 */
class V8_BASE_EXPORT EmulatedVirtualAddressSubspace final
    : public NON_EXPORTED_BASE(::v8::VirtualAddressSpace) { … };

}  // namespace base
}  // namespace v8

#endif  // V8_BASE_EMULATED_VIRTUAL_ADDRESS_SUBSPACE_H_