1/* @title: Page */
2#pragma once
3#include <compiler.h>
4#include <global.h>
5#include <math/align.h>
6#include <math/kb_mb_gb_tb.h>
7#include <mem/hhdm.h>
8#include <stdint.h>
9#include <sync/spinlock.h>
10
11struct folio;
12
13#define PAGE_SIZE KB(4)
14#define PAGE_2MB MB(2)
15#define PAGE_1GB GB(1)
16
17#define PAGE_PRESENT_SHIFT (0)
18#define PAGE_PRESENT (0x1UL)
19#define PAGE_WRITE (0x2UL)
20#define PAGE_USER_ALLOWED (0x4UL)
21#define PAGE_ALL 0xFFFUL
22#define PAGE_XD (1UL << 63) // E(x)ecute (D)isable
23#define PAGE_PHYS_MASK (0x00FFFFFFF000UL)
24#define PAGE_PAGE_SIZE (1UL << 7)
25#define PAGE_UNCACHABLE ((1UL << 4) | PAGE_WRITE)
26#define PAGE_NO_FLAGS (0)
27#define PAGE_WRITETHROUGH (1UL << 3)
28#define PAGE_2MB_page (1ULL << 7)
29
30/* TODO: */
31#define PAGE_PAGEABLE (0)
32#define PAGE_MOVABLE (0)
33
34#define PAGE_2MB_PHYS_MASK (~((uintptr_t) PAGE_2MB - 1))
35#define PAGE_ALIGN_DOWN(x) ALIGN_DOWN((uintptr_t) (x), PAGE_SIZE)
36#define PAGE_ALIGN_UP(x) ALIGN_UP((uintptr_t) (x), PAGE_SIZE)
37#define IS_PAGE_ALIGNED(x) IS_ALIGNED((uintptr_t) (x), PAGE_SIZE)
38#define PAGE_2MB_ALIGN_DOWN(x) ALIGN_DOWN((uintptr_t) (x), PAGE_2MB)
39#define PAGE_2MB_ALIGN_UP(x) ALIGN_UP((uintptr_t) (x), PAGE_2MB)
40#define PAGE_1GB_ALIGN_DOWN(x) ALIGN_DOWN((uintptr_t) (x), PAGE_1GB)
41#define PAGE_1GB_ALIGN_UP(x) ALIGN_UP((uintptr_t) (x), PAGE_1GB)
42
43#define PAGE_TO_PFN(addr) ((addr) / PAGE_SIZE)
44#define PFN_TO_PAGE(pfn) ((pfn) * PAGE_SIZE)
45
46#define PAGES_NEEDED_FOR(bytes) (((bytes) + PAGE_SIZE - 1ULL) / PAGE_SIZE)
47
48#define VMM_MAP_BASE 0xFFFFA00000200000
49#define VMM_MAP_LIMIT 0xFFFFA00010000000
50#define PT_ENTRIES 512
51#define PT_INDEX_MASK 0x1FFULL
52
53#define PAGE_4K_SHIFT 12
54#define PAGE_2M_SHIFT 21
55#define PAGE_1G_SHIFT 30
56#define PAGE_4K_MASK ((1ULL << PAGE_4K_SHIFT) - 1)
57#define PAGE_2M_MASK ((1ULL << PAGE_2M_SHIFT) - 1)
58
59#define PAGE_TAG_MASK 0x7ULL
60#define PAGE_PAYLOAD_ALIGNMENT 8
61
62enum page_tag {
63 /* Low 3 bits */
64 PAGE_TAG_NONE = 0,
65 PAGE_TAG_BUDDY = 1,
66 PAGE_TAG_FOLIO = 2,
67 PAGE_TAG_ARENA = 3, /* cached as a free single page in a domain arena */
68};
69
70struct page {
71 uint64_t meta;
72};
73
74struct page_table {
75 pte_t entries[512];
76} __packed;
77_Static_assert(sizeof(struct page_table) == PAGE_SIZE, "");
78
79static inline enum page_tag page_get_tag(const struct page *p) {
80 return (enum page_tag)(p->meta & PAGE_TAG_MASK);
81}
82
83static inline void page_set_tag(struct page *p, enum page_tag tag) {
84 p->meta = (p->meta & ~PAGE_TAG_MASK) | (tag & PAGE_TAG_MASK);
85}
86
87static inline uint64_t page_get_payload(const struct page *p) {
88 return p->meta & ~PAGE_TAG_MASK;
89}
90
91static inline void page_set_payload(struct page *p, uint64_t payload) {
92 p->meta = (p->meta & PAGE_TAG_MASK) | (payload & ~PAGE_TAG_MASK);
93}
94
95static inline void page_assert_tag(const struct page *p,
96 enum page_tag expected) {
97 kassert(page_get_tag(p) == expected);
98}
99
100static inline struct page *page_for_pfn(pfn_t pfn) {
101 if (pfn >= global.last_pfn)
102 return NULL;
103
104 return &global.page_array[pfn];
105}
106
107static inline struct page *page_for_paddr(paddr_t paddr) {
108 return page_for_pfn(PAGE_TO_PFN(paddr));
109}
110
111static inline pfn_t page_get_pfn(const struct page *bp) {
112 return (pfn_t) (bp - global.page_array);
113}
114
115static inline paddr_t page_get_paddr(const struct page *bp) {
116 return PFN_TO_PAGE(page_get_pfn(bp));
117}
118
119static inline vaddr_t page_get_vaddr(const struct page *bp) {
120 return hhdm_paddr_to_vaddr(p: page_get_paddr(bp));
121}
122