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
|
#include "kernel.h"
enum PAGE_PTE_FLAGS {
I86_PTE_PRESENT = 1, //0000000000000000000000000000001
I86_PTE_WRITABLE = 2, //0000000000000000000000000000010
I86_PTE_USER = 4, //0000000000000000000000000000100
I86_PTE_WRITETHOUGH = 8, //0000000000000000000000000001000
I86_PTE_NOT_CACHEABLE = 0x10, //0000000000000000000000000010000
I86_PTE_ACCESSED = 0x20, //0000000000000000000000000100000
I86_PTE_DIRTY = 0x40, //0000000000000000000000001000000
I86_PTE_PAT = 0x80, //0000000000000000000000010000000
I86_PTE_CPU_GLOBAL = 0x100, //0000000000000000000000100000000
I86_PTE_LV4_GLOBAL = 0x200, //0000000000000000000001000000000
I86_PTE_FRAME = 0x7FFFF000 //1111111111111111111000000000000
};
enum PAGE_PDE_FLAGS {
I86_PDE_PRESENT = 1, //0000000000000000000000000000001
I86_PDE_WRITABLE = 2, //0000000000000000000000000000010
I86_PDE_USER = 4, //0000000000000000000000000000100
I86_PDE_PWT = 8, //0000000000000000000000000001000
I86_PDE_PCD = 0x10, //0000000000000000000000000010000
I86_PDE_ACCESSED = 0x20, //0000000000000000000000000100000
I86_PDE_DIRTY = 0x40, //0000000000000000000000001000000
I86_PDE_4MB = 0x80, //0000000000000000000000010000000
I86_PDE_CPU_GLOBAL = 0x100, //0000000000000000000000100000000
I86_PDE_LV4_GLOBAL = 0x200, //0000000000000000000001000000000
I86_PDE_FRAME = 0x7FFFF000 //1111111111111111111000000000000
};
//! page table entry
typedef uint32_t pt_entry;
//! a page directery entry
typedef uint32_t pd_entry;
////
//! virtual address
typedef uint32_t virtual_addr;
//! i86 architecture defines 1024 entries per table--do not change
#define PAGES_PER_TABLE 1024
#define PAGES_PER_DIR 1024
#define PAGE_DIRECTORY_INDEX(x) (((x) >> 22) & 0x3ff)
#define PAGE_TABLE_INDEX(x) (((x) >> 12) & 0x3ff)
#define PAGE_GET_PHYSICAL_ADDRESS(x) (*x & ~0xfff)
//! page table represents 4mb address space
#define PTABLE_ADDR_SPACE_SIZE 0x400000
//! directory table represents 4gb address space
#define DTABLE_ADDR_SPACE_SIZE 0x100000000
//! page sizes are 4k
#define PAGE_SIZE 4096
//! page table
struct ptable {
pt_entry m_entries[PAGES_PER_TABLE];
};
//! page directory
struct pdirectory {
pd_entry m_entries[PAGES_PER_DIR];
};
void vmem_init()
{
scr_put_string_nl("todo: init paging");
}
|
