1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2020 Loongson Technology Corporation Limited
4  */
5 #ifndef _ASM_PGTABLE_64_H
6 #define _ASM_PGTABLE_64_H
7 
8 #include <linux/compiler.h>
9 #include <linux/linkage.h>
10 
11 #include <asm/addrspace.h>
12 
13 #if CONFIG_PGTABLE_LEVELS == 2
14 #include <asm-generic/pgtable-nopmd.h>
15 #elif CONFIG_PGTABLE_LEVELS == 3
16 #include <asm-generic/pgtable-nopud.h>
17 #else
18 #include <asm-generic/pgtable-nop4d.h>
19 #endif
20 
21 #define PGD_ORDER		0
22 #define PUD_ORDER		0
23 #define PMD_ORDER		0
24 #define PTE_ORDER		0
25 
26 #if CONFIG_PGTABLE_LEVELS == 2
27 #define PGDIR_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
28 #elif CONFIG_PGTABLE_LEVELS == 3
29 #define PMD_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
30 #define PMD_SIZE	(1UL << PMD_SHIFT)
31 #define PMD_MASK	(~(PMD_SIZE-1))
32 #define PGDIR_SHIFT	(PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
33 #elif CONFIG_PGTABLE_LEVELS == 4
34 #define PMD_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
35 #define PMD_SIZE	(1UL << PMD_SHIFT)
36 #define PMD_MASK	(~(PMD_SIZE-1))
37 #define PUD_SHIFT	(PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
38 #define PUD_SIZE	(1UL << PUD_SHIFT)
39 #define PUD_MASK	(~(PUD_SIZE-1))
40 #define PGDIR_SHIFT	(PUD_SHIFT + (PAGE_SHIFT + PUD_ORDER - 3))
41 #endif
42 
43 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
44 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
45 
46 #define VA_BITS		(PGDIR_SHIFT + (PAGE_SHIFT + PGD_ORDER - 3))
47 
48 #define PTRS_PER_PGD	((PAGE_SIZE << PGD_ORDER) >> 3)
49 #if CONFIG_PGTABLE_LEVELS > 3
50 #define PTRS_PER_PUD	((PAGE_SIZE << PUD_ORDER) >> 3)
51 #endif
52 #if CONFIG_PGTABLE_LEVELS > 2
53 #define PTRS_PER_PMD	((PAGE_SIZE << PMD_ORDER) >> 3)
54 #endif
55 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) >> 3)
56 
57 #define USER_PTRS_PER_PGD       ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
58 #define FIRST_USER_ADDRESS	0UL
59 
60 #ifndef __ASSEMBLY__
61 
62 #include <asm/fixmap.h>
63 #include <asm/sparsemem.h>
64 
65 /*
66  * TLB refill handlers may also map the vmalloc area into xkvrange.
67  * Avoid the first couple of pages so NULL pointer dereferences will
68  * still reliably trap.
69  */
70 #define MODULES_VADDR	(vm_map_base + PCI_IOSIZE + (2 * PAGE_SIZE))
71 #define MODULES_END	(MODULES_VADDR + SZ_256M)
72 
73 #define VMALLOC_START	MODULES_END
74 
75 #ifndef CONFIG_KASAN
76 #define VMALLOC_END	\
77 	(vm_map_base +	\
78 	 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits)) - PMD_SIZE - VMEMMAP_SIZE)
79 #else
80 #define VMALLOC_END	\
81 	(vm_map_base +	\
82 	 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, (1UL << cpu_vabits) / 2) - PMD_SIZE - VMEMMAP_SIZE)
83 #endif
84 
85 #define vmemmap		((struct page *)((VMALLOC_END + PMD_SIZE) & PMD_MASK))
86 #define VMEMMAP_END	((unsigned long)vmemmap + VMEMMAP_SIZE - 1)
87 
88 #define pte_ERROR(e) \
89 	printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
90 #ifndef __PAGETABLE_PMD_FOLDED
91 #define pmd_ERROR(e) \
92 	printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
93 #endif
94 #ifndef __PAGETABLE_PUD_FOLDED
95 #define pud_ERROR(e) \
96 	printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
97 #endif
98 #define pgd_ERROR(e) \
99 	printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
100 
101 extern pte_t invalid_pte_table[PTRS_PER_PTE];
102 
103 #ifndef __PAGETABLE_PUD_FOLDED
104 
105 typedef struct { unsigned long pud; } pud_t;
106 #define pud_val(x)	((x).pud)
107 #define __pud(x)	((pud_t) { (x) })
108 
109 extern pud_t invalid_pud_table[PTRS_PER_PUD];
110 
111 /*
112  * Empty pgd/p4d entries point to the invalid_pud_table.
113  */
p4d_none(p4d_t p4d)114 static inline int p4d_none(p4d_t p4d)
115 {
116 	return p4d_val(p4d) == (unsigned long)invalid_pud_table;
117 }
118 
p4d_bad(p4d_t p4d)119 static inline int p4d_bad(p4d_t p4d)
120 {
121 	return p4d_val(p4d) & ~PAGE_MASK;
122 }
123 
p4d_present(p4d_t p4d)124 static inline int p4d_present(p4d_t p4d)
125 {
126 	return p4d_val(p4d) != (unsigned long)invalid_pud_table;
127 }
128 
p4d_clear(p4d_t *p4dp)129 static inline void p4d_clear(p4d_t *p4dp)
130 {
131 	p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
132 }
133 
p4d_pgtable(p4d_t p4d)134 static inline pud_t *p4d_pgtable(p4d_t p4d)
135 {
136 	return (pud_t *)p4d_val(p4d);
137 }
138 
set_p4d(p4d_t *p4d, p4d_t p4dval)139 static inline void set_p4d(p4d_t *p4d, p4d_t p4dval)
140 {
141 	*p4d = p4dval;
142 }
143 
144 #define p4d_phys(p4d)		PHYSADDR(p4d_val(p4d))
145 #define p4d_page(p4d)		(pfn_to_page(p4d_phys(p4d) >> PAGE_SHIFT))
146 
147 #endif
148 
149 #ifndef __PAGETABLE_PMD_FOLDED
150 
151 typedef struct { unsigned long pmd; } pmd_t;
152 #define pmd_val(x)	((x).pmd)
153 #define __pmd(x)	((pmd_t) { (x) } )
154 
155 extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
156 
157 /*
158  * Empty pud entries point to the invalid_pmd_table.
159  */
pud_none(pud_t pud)160 static inline int pud_none(pud_t pud)
161 {
162 	return pud_val(pud) == (unsigned long)invalid_pmd_table;
163 }
164 
pud_bad(pud_t pud)165 static inline int pud_bad(pud_t pud)
166 {
167 	return pud_val(pud) & ~PAGE_MASK;
168 }
169 
pud_present(pud_t pud)170 static inline int pud_present(pud_t pud)
171 {
172 	return pud_val(pud) != (unsigned long)invalid_pmd_table;
173 }
174 
pud_clear(pud_t *pudp)175 static inline void pud_clear(pud_t *pudp)
176 {
177 	pud_val(*pudp) = ((unsigned long)invalid_pmd_table);
178 }
179 
pud_pgtable(pud_t pud)180 static inline pmd_t *pud_pgtable(pud_t pud)
181 {
182 	return (pmd_t *)pud_val(pud);
183 }
184 
185 #define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while (0)
186 
187 #define pud_phys(pud)		PHYSADDR(pud_val(pud))
188 #define pud_page(pud)		(pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
189 
190 #endif
191 
192 /*
193  * Empty pmd entries point to the invalid_pte_table.
194  */
pmd_none(pmd_t pmd)195 static inline int pmd_none(pmd_t pmd)
196 {
197 	return pmd_val(pmd) == (unsigned long)invalid_pte_table;
198 }
199 
pmd_bad(pmd_t pmd)200 static inline int pmd_bad(pmd_t pmd)
201 {
202 	return (pmd_val(pmd) & ~PAGE_MASK);
203 }
204 
pmd_present(pmd_t pmd)205 static inline int pmd_present(pmd_t pmd)
206 {
207 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
208 		return !!(pmd_val(pmd) & (_PAGE_PRESENT | _PAGE_PROTNONE | _PAGE_PRESENT_INVALID));
209 
210 	return pmd_val(pmd) != (unsigned long)invalid_pte_table;
211 }
212 
pmd_clear(pmd_t *pmdp)213 static inline void pmd_clear(pmd_t *pmdp)
214 {
215 	pmd_val(*pmdp) = ((unsigned long)invalid_pte_table);
216 }
217 
218 #define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while (0)
219 
220 #define pmd_phys(pmd)		PHYSADDR(pmd_val(pmd))
221 
222 #ifndef CONFIG_TRANSPARENT_HUGEPAGE
223 #define pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
224 #endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
225 
226 #define pmd_page_vaddr(pmd)	pmd_val(pmd)
227 
228 extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
229 extern void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd);
230 
231 #define pte_page(x)		pfn_to_page(pte_pfn(x))
232 #define pte_pfn(x)		((unsigned long)(((x).pte & _PFN_MASK) >> _PFN_SHIFT))
233 #define pfn_pte(pfn, prot)	__pte(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
234 #define pfn_pmd(pfn, prot)	__pmd(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
235 
236 /*
237  * Initialize a new pgd / pmd table with invalid pointers.
238  */
239 extern void pgd_init(unsigned long page);
240 extern void pud_init(unsigned long page, unsigned long pagetable);
241 extern void pmd_init(unsigned long page, unsigned long pagetable);
242 
243 /*
244  * Non-present pages:  high 40 bits are offset, next 8 bits type,
245  * low 16 bits zero.
246  */
mk_swap_pte(unsigned long type, unsigned long offset)247 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
248 { pte_t pte; pte_val(pte) = (type << 16) | (offset << 24); return pte; }
249 
250 #define __swp_type(x)		(((x).val >> 16) & 0xff)
251 #define __swp_offset(x)		((x).val >> 24)
252 #define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
253 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
254 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
255 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
256 #define __swp_entry_to_pmd(x)	((pmd_t) { (x).val | _PAGE_HUGE })
257 
258 #endif /* !__ASSEMBLY__ */
259 
260 #endif /* _ASM_PGTABLE_64_H */
261