| /* |
| * Copyright (C) 2017 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #pragma once |
| |
| #include "BMalloced.h" |
| #include "IsoDirectory.h" |
| |
| namespace bmalloc { |
| |
| template<typename Config> |
| class IsoDirectoryPage { |
| MAKE_BMALLOCED; |
| public: |
| // By my math, this results in an IsoDirectoryPage using 4036 bytes on 64-bit platforms. We allocate it |
| // with malloc, so it doesn't really matter how much memory it uses. But it's nice that this about a |
| // page, since that's quite intuitive. |
| // |
| // On 32-bit platforms, I think that this will be 2112 bytes. That's still quite intuitive. |
| // |
| // Note that this is a multiple of 32 so that it uses bitvectors efficiently. |
| static constexpr unsigned numPages = 480; |
| |
| IsoDirectoryPage(IsoHeapImpl<Config>&, unsigned index); |
| |
| static IsoDirectoryPage* pageFor(IsoDirectory<Config, numPages>* payload); |
| |
| unsigned index() const { return m_index; } |
| |
| IsoDirectory<Config, numPages> payload; |
| IsoDirectoryPage* next { nullptr }; |
| |
| private: |
| unsigned m_index; |
| }; |
| |
| } // namespace bmalloc |
| |