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_XD (1UL << 63) // E(x)ecute (D)isable
22#define PAGE_PHYS_MASK (0x00FFFFFFF000UL)
23#define PAGE_UNCACHABLE (1UL << 4) /* PCD */
24#define PAGE_NO_FLAGS (0)
25#define PAGE_WRITETHROUGH (1UL << 3)
26#define PAGE_HUGE (1ULL << 7) /* PS: 2MB at the PD level, 1GB at the PDPT */
27
28/* TODO: */
29#define PAGE_PAGEABLE (0)
30#define PAGE_MOVABLE (0)
31
32#define PAGE_2MB_PHYS_MASK (0x00FFFFE00000UL)
33#define PAGE_1GB_PHYS_MASK (0x00FFC0000000UL)
34#define PAGE_ALIGN_DOWN(x) ALIGN_DOWN((uintptr_t) (x), PAGE_SIZE)
35#define PAGE_ALIGN_UP(x) ALIGN_UP((uintptr_t) (x), PAGE_SIZE)
36#define IS_PAGE_ALIGNED(x) IS_ALIGNED((uintptr_t) (x), PAGE_SIZE)
37#define PAGE_2MB_ALIGN_DOWN(x) ALIGN_DOWN((uintptr_t) (x), PAGE_2MB)
38#define PAGE_2MB_ALIGN_UP(x) ALIGN_UP((uintptr_t) (x), PAGE_2MB)
39#define PAGE_1GB_ALIGN_DOWN(x) ALIGN_DOWN((uintptr_t) (x), PAGE_1GB)
40#define PAGE_1GB_ALIGN_UP(x) ALIGN_UP((uintptr_t) (x), PAGE_1GB)
41
42#define PAGE_TO_PFN(addr) ((addr) / PAGE_SIZE)
43#define PFN_TO_PAGE(pfn) ((pfn) * PAGE_SIZE)
44
45#define PAGES_NEEDED_FOR(bytes) (((bytes) + PAGE_SIZE - 1ULL) / PAGE_SIZE)
46
47#define VMM_MAP_BASE 0xFFFFA00000200000
48#define VMM_MAP_LIMIT 0xFFFFA00010000000
49#define PT_ENTRIES 512
50#define PT_INDEX_MASK 0x1FFULL
51
52#define PAGE_4K_SHIFT 12
53#define PAGE_2M_SHIFT 21
54#define PAGE_1G_SHIFT 30
55
56#define PAGE_TAG_MASK 0x7ULL
57#define PAGE_PAYLOAD_ALIGNMENT 8
58
59enum page_tag {
60 /* Low 3 bits */
61 PAGE_TAG_NONE = 0,
62 PAGE_TAG_BUDDY = 1,
63 PAGE_TAG_FOLIO = 2,
64 PAGE_TAG_ARENA = 3, /* cached as a free single page in a domain arena */
65};
66
67struct page {
68 uint64_t meta;
69};
70
71struct page_table {
72 pte_t entries[512];
73} __packed;
74_Static_assert(sizeof(struct page_table) == PAGE_SIZE, "");
75
76static inline enum page_tag page_get_tag(const struct page *p) {
77 return (enum page_tag)(p->meta & PAGE_TAG_MASK);
78}
79
80static inline void page_set_tag(struct page *p, enum page_tag tag) {
81 p->meta = (p->meta & ~PAGE_TAG_MASK) | (tag & PAGE_TAG_MASK);
82}
83
84static inline uint64_t page_get_payload(const struct page *p) {
85 return p->meta & ~PAGE_TAG_MASK;
86}
87
88static inline void page_set_payload(struct page *p, uint64_t payload) {
89 p->meta = (p->meta & PAGE_TAG_MASK) | (payload & ~PAGE_TAG_MASK);
90}
91
92static inline void page_assert_tag(const struct page *p,
93 enum page_tag expected) {
94 kassert(page_get_tag(p) == expected);
95}
96
97static inline struct page *page_for_pfn(pfn_t pfn) {
98 if (pfn >= global.last_pfn)
99 return NULL;
100
101 return &global.page_array[pfn];
102}
103
104static inline struct page *page_for_paddr(paddr_t paddr) {
105 return page_for_pfn(PAGE_TO_PFN(paddr));
106}
107
108static inline pfn_t page_get_pfn(const struct page *bp) {
109 return (pfn_t) (bp - global.page_array);
110}
111
112static inline paddr_t page_get_paddr(const struct page *bp) {
113 return PFN_TO_PAGE(page_get_pfn(bp));
114}
115
116static inline vaddr_t page_get_vaddr(const struct page *bp) {
117 return hhdm_paddr_to_vaddr(p: page_get_paddr(bp));
118}
119