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Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#pragma once
28
29#include <Kernel/VM/AnonymousVMObject.h>
30
31namespace Kernel {
32
33class PurgeableVMObject final : public AnonymousVMObject {
34public:
35 virtual ~PurgeableVMObject() override;
36
37 static NonnullRefPtr<PurgeableVMObject> create_with_size(size_t);
38 virtual NonnullRefPtr<VMObject> clone() override;
39
40 int purge();
41 int purge_with_interrupts_disabled(Badge<MemoryManager>);
42
43 bool was_purged() const { return m_was_purged; }
44 void set_was_purged(bool b) { m_was_purged = b; }
45
46 bool is_volatile() const { return m_volatile; }
47 void set_volatile(bool b) { m_volatile = b; }
48
49private:
50 explicit PurgeableVMObject(size_t);
51 explicit PurgeableVMObject(const PurgeableVMObject&);
52
53 virtual const char* class_name() const override { return "PurgeableVMObject"; }
54
55 int purge_impl();
56
57 PurgeableVMObject& operator=(const PurgeableVMObject&) = delete;
58 PurgeableVMObject& operator=(PurgeableVMObject&&) = delete;
59 PurgeableVMObject(PurgeableVMObject&&) = delete;
60
61 virtual bool is_purgeable() const override { return true; }
62
63 bool m_was_purged { false };
64 bool m_volatile { false };
65};
66
67}