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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#include <Kernel/Heap/kmalloc.h>
28#include <Kernel/VM/MemoryManager.h>
29#include <Kernel/VM/PhysicalPage.h>
30
31namespace Kernel {
32
33NonnullRefPtr<PhysicalPage> PhysicalPage::create(PhysicalAddress paddr, bool supervisor, bool may_return_to_freelist)
34{
35 return adopt(*new PhysicalPage(paddr, supervisor, may_return_to_freelist));
36}
37
38PhysicalPage::PhysicalPage(PhysicalAddress paddr, bool supervisor, bool may_return_to_freelist)
39 : m_may_return_to_freelist(may_return_to_freelist)
40 , m_supervisor(supervisor)
41 , m_paddr(paddr)
42{
43}
44
45void PhysicalPage::return_to_freelist() &&
46{
47 ASSERT((paddr().get() & ~PAGE_MASK) == 0);
48
49 InterruptDisabler disabler;
50
51 m_ref_count = 1;
52
53 if (m_supervisor)
54 MM.deallocate_supervisor_physical_page(move(*this));
55 else
56 MM.deallocate_user_physical_page(move(*this));
57
58#ifdef MM_DEBUG
59 dbg() << "MM: P" << String::format("%x", m_paddr.get()) << " released to freelist";
60#endif
61}
62
63}