1 /* SPDX-License-Identifier: GPL-2.0
2 *
3 * This file contains the functions and defines necessary to modify and
4 * use the SuperH page table tree.
5 *
6 * Copyright (C) 1999 Niibe Yutaka
7 * Copyright (C) 2002 - 2007 Paul Mundt
8 */
9 #ifndef __ASM_SH_PGTABLE_H
10 #define __ASM_SH_PGTABLE_H
11
12 #ifdef CONFIG_X2TLB
13 #include <asm/pgtable-3level.h>
14 #else
15 #include <asm/pgtable-2level.h>
16 #endif
17 #include <asm/page.h>
18 #include <asm/mmu.h>
19
20 #ifndef __ASSEMBLY__
21 #include <asm/addrspace.h>
22 #include <asm/fixmap.h>
23
24 /*
25 * ZERO_PAGE is a global shared page that is always zero: used
26 * for zero-mapped memory areas etc..
27 */
28 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
29 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
30
31 #endif /* !__ASSEMBLY__ */
32
33 /*
34 * Effective and physical address definitions, to aid with sign
35 * extension.
36 */
37 #define NEFF 32
38 #define NEFF_SIGN (1LL << (NEFF - 1))
39 #define NEFF_MASK (-1LL << NEFF)
40
neff_sign_extend(unsigned long val)41 static inline unsigned long long neff_sign_extend(unsigned long val)
42 {
43 unsigned long long extended = val;
44 return (extended & NEFF_SIGN) ? (extended | NEFF_MASK) : extended;
45 }
46
47 #ifdef CONFIG_29BIT
48 #define NPHYS 29
49 #else
50 #define NPHYS 32
51 #endif
52
53 #define NPHYS_SIGN (1LL << (NPHYS - 1))
54 #define NPHYS_MASK (-1LL << NPHYS)
55
56 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
57 #define PGDIR_MASK (~(PGDIR_SIZE-1))
58
59 /* Entries per level */
60 #define PTRS_PER_PTE (PAGE_SIZE / (1 << PTE_MAGNITUDE))
61
62 #define PHYS_ADDR_MASK29 0x1fffffff
63 #define PHYS_ADDR_MASK32 0xffffffff
64
phys_addr_mask(void)65 static inline unsigned long phys_addr_mask(void)
66 {
67 /* Is the MMU in 29bit mode? */
68 if (__in_29bit_mode())
69 return PHYS_ADDR_MASK29;
70
71 return PHYS_ADDR_MASK32;
72 }
73
74 #define PTE_PHYS_MASK (phys_addr_mask() & PAGE_MASK)
75 #define PTE_FLAGS_MASK (~(PTE_PHYS_MASK) << PAGE_SHIFT)
76
77 #define VMALLOC_START (P3SEG)
78 #define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
79
80 #include <asm/pgtable_32.h>
81
82 /*
83 * SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
84 * protection for execute, and considers it the same as a read. Also, write
85 * permission implies read permission. This is the closest we can get..
86 *
87 * SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
88 * not only supporting separate execute, read, and write bits, but having
89 * completely separate permission bits for user and kernel space.
90 */
91 /*xwr*/
92
93 typedef pte_t *pte_addr_t;
94
95 #define kern_addr_valid(addr) (1)
96
97 #define pte_pfn(x) ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
98
99 struct vm_area_struct;
100 struct mm_struct;
101
102 extern void __update_cache(struct vm_area_struct *vma,
103 unsigned long address, pte_t pte);
104 extern void __update_tlb(struct vm_area_struct *vma,
105 unsigned long address, pte_t pte);
106
107 static inline void
update_mmu_cache(struct vm_area_struct * vma,unsigned long address,pte_t * ptep)108 update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
109 {
110 pte_t pte = *ptep;
111 __update_cache(vma, address, pte);
112 __update_tlb(vma, address, pte);
113 }
114
115 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
116 extern void paging_init(void);
117 extern void page_table_range_init(unsigned long start, unsigned long end,
118 pgd_t *pgd);
119
__pte_access_permitted(pte_t pte,u64 prot)120 static inline bool __pte_access_permitted(pte_t pte, u64 prot)
121 {
122 return (pte_val(pte) & (prot | _PAGE_SPECIAL)) == prot;
123 }
124
125 #ifdef CONFIG_X2TLB
pte_access_permitted(pte_t pte,bool write)126 static inline bool pte_access_permitted(pte_t pte, bool write)
127 {
128 u64 prot = _PAGE_PRESENT;
129
130 prot |= _PAGE_EXT(_PAGE_EXT_KERN_READ | _PAGE_EXT_USER_READ);
131 if (write)
132 prot |= _PAGE_EXT(_PAGE_EXT_KERN_WRITE | _PAGE_EXT_USER_WRITE);
133 return __pte_access_permitted(pte, prot);
134 }
135 #else
pte_access_permitted(pte_t pte,bool write)136 static inline bool pte_access_permitted(pte_t pte, bool write)
137 {
138 u64 prot = _PAGE_PRESENT | _PAGE_USER;
139
140 if (write)
141 prot |= _PAGE_RW;
142 return __pte_access_permitted(pte, prot);
143 }
144 #endif
145
146 #define pte_access_permitted pte_access_permitted
147
148 /* arch/sh/mm/mmap.c */
149 #define HAVE_ARCH_UNMAPPED_AREA
150 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
151
152 #endif /* __ASM_SH_PGTABLE_H */
153
