summaryrefslogtreecommitdiff
path: root/Kernel/VM/MemoryManager.h
blob: 399d0f15024b994b279f13e476f13b06ed16cbd7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
#pragma once

#include <AK/String.h>
#include <AK/Badge.h>
#include <AK/Bitmap.h>
#include <AK/ByteBuffer.h>
#include <AK/HashTable.h>
#include <AK/NonnullRefPtrVector.h>
#include <AK/RefCounted.h>
#include <AK/RefPtr.h>
#include <AK/Types.h>
#include <AK/Vector.h>
#include <AK/Weakable.h>
#include <Kernel/Arch/i386/CPU.h>
#include <Kernel/FileSystem/InodeIdentifier.h>
#include <Kernel/VM/PhysicalPage.h>
#include <Kernel/VM/PhysicalRegion.h>
#include <Kernel/VM/Region.h>
#include <Kernel/VM/VMObject.h>

#define PAGE_ROUND_UP(x) ((((u32)(x)) + PAGE_SIZE - 1) & (~(PAGE_SIZE - 1)))

class KBuffer;
class SynthFSInode;

#define MM MemoryManager::the()

class MemoryManager {
    AK_MAKE_ETERNAL
    friend class PageDirectory;
    friend class PhysicalPage;
    friend class PhysicalRegion;
    friend class Region;
    friend class VMObject;
    friend Optional<KBuffer> procfs$mm(InodeIdentifier);
    friend Optional<KBuffer> procfs$memstat(InodeIdentifier);

public:
    static MemoryManager& the();

    static void initialize(u32 physical_address_for_kernel_page_tables);

    PageFaultResponse handle_page_fault(const PageFault&);

    void populate_page_directory(PageDirectory&);

    void enter_process_paging_scope(Process&);

    bool validate_user_read(const Process&, VirtualAddress) const;
    bool validate_user_write(const Process&, VirtualAddress) const;

    enum class ShouldZeroFill {
        No,
        Yes
    };

    RefPtr<PhysicalPage> allocate_user_physical_page(ShouldZeroFill);
    RefPtr<PhysicalPage> allocate_supervisor_physical_page();
    void deallocate_user_physical_page(PhysicalPage&&);
    void deallocate_supervisor_physical_page(PhysicalPage&&);

    void map_for_kernel(VirtualAddress, PhysicalAddress, bool cache_disabled = false);

    OwnPtr<Region> allocate_kernel_region(size_t, const StringView& name, bool user_accessible = false, bool should_commit = true);
    OwnPtr<Region> allocate_user_accessible_kernel_region(size_t, const StringView& name);

    unsigned user_physical_pages() const { return m_user_physical_pages; }
    unsigned user_physical_pages_used() const { return m_user_physical_pages_used; }
    unsigned super_physical_pages() const { return m_super_physical_pages; }
    unsigned super_physical_pages_used() const { return m_super_physical_pages_used; }

    template<typename Callback>
    static void for_each_vmobject(Callback callback)
    {
        for (auto& vmobject : MM.m_vmobjects) {
            if (callback(vmobject) == IterationDecision::Break)
                break;
        }
    }

private:
    MemoryManager(u32 physical_address_for_kernel_page_tables);
    ~MemoryManager();

    void register_vmo(VMObject&);
    void unregister_vmo(VMObject&);
    void register_region(Region&);
    void unregister_region(Region&);

    void initialize_paging();
    void flush_entire_tlb();
    void flush_tlb(VirtualAddress);

    void map_protected(VirtualAddress, size_t length);

    void create_identity_mapping(PageDirectory&, VirtualAddress, size_t length);

    static Region* region_from_vaddr(Process&, VirtualAddress);
    static const Region* region_from_vaddr(const Process&, VirtualAddress);

    static Region* user_region_from_vaddr(Process&, VirtualAddress);
    static Region* kernel_region_from_vaddr(VirtualAddress);

    static Region* region_from_vaddr(VirtualAddress);

    RefPtr<PhysicalPage> find_free_user_physical_page();
    u8* quickmap_page(PhysicalPage&);
    void unquickmap_page();

    PageDirectory& kernel_page_directory() { return *m_kernel_page_directory; }

    PageTableEntry& ensure_pte(PageDirectory&, VirtualAddress);

    RefPtr<PageDirectory> m_kernel_page_directory;
    PageTableEntry* m_page_table_zero { nullptr };
    PageTableEntry* m_page_table_one { nullptr };

    VirtualAddress m_quickmap_addr;

    unsigned m_user_physical_pages { 0 };
    unsigned m_user_physical_pages_used { 0 };
    unsigned m_super_physical_pages { 0 };
    unsigned m_super_physical_pages_used { 0 };

    NonnullRefPtrVector<PhysicalRegion> m_user_physical_regions;
    NonnullRefPtrVector<PhysicalRegion> m_super_physical_regions;

    InlineLinkedList<Region> m_user_regions;
    InlineLinkedList<Region> m_kernel_regions;

    InlineLinkedList<VMObject> m_vmobjects;

    bool m_quickmap_in_use { false };
};

struct ProcessPagingScope {
    ProcessPagingScope(Process&);
    ~ProcessPagingScope();
};