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Linux kernel mirror (for testing)
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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 */
28extern 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
41static 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 FIRST_USER_ADDRESS 0UL
63
64#define PHYS_ADDR_MASK29 0x1fffffff
65#define PHYS_ADDR_MASK32 0xffffffff
66
67static inline unsigned long phys_addr_mask(void)
68{
69 /* Is the MMU in 29bit mode? */
70 if (__in_29bit_mode())
71 return PHYS_ADDR_MASK29;
72
73 return PHYS_ADDR_MASK32;
74}
75
76#define PTE_PHYS_MASK (phys_addr_mask() & PAGE_MASK)
77#define PTE_FLAGS_MASK (~(PTE_PHYS_MASK) << PAGE_SHIFT)
78
79#define VMALLOC_START (P3SEG)
80#define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
81
82#include <asm/pgtable_32.h>
83
84/*
85 * SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
86 * protection for execute, and considers it the same as a read. Also, write
87 * permission implies read permission. This is the closest we can get..
88 *
89 * SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
90 * not only supporting separate execute, read, and write bits, but having
91 * completely separate permission bits for user and kernel space.
92 */
93 /*xwr*/
94#define __P000 PAGE_NONE
95#define __P001 PAGE_READONLY
96#define __P010 PAGE_COPY
97#define __P011 PAGE_COPY
98#define __P100 PAGE_EXECREAD
99#define __P101 PAGE_EXECREAD
100#define __P110 PAGE_COPY
101#define __P111 PAGE_COPY
102
103#define __S000 PAGE_NONE
104#define __S001 PAGE_READONLY
105#define __S010 PAGE_WRITEONLY
106#define __S011 PAGE_SHARED
107#define __S100 PAGE_EXECREAD
108#define __S101 PAGE_EXECREAD
109#define __S110 PAGE_RWX
110#define __S111 PAGE_RWX
111
112typedef pte_t *pte_addr_t;
113
114#define kern_addr_valid(addr) (1)
115
116#define pte_pfn(x) ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
117
118struct vm_area_struct;
119struct mm_struct;
120
121extern void __update_cache(struct vm_area_struct *vma,
122 unsigned long address, pte_t pte);
123extern void __update_tlb(struct vm_area_struct *vma,
124 unsigned long address, pte_t pte);
125
126static inline void
127update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
128{
129 pte_t pte = *ptep;
130 __update_cache(vma, address, pte);
131 __update_tlb(vma, address, pte);
132}
133
134extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
135extern void paging_init(void);
136extern void page_table_range_init(unsigned long start, unsigned long end,
137 pgd_t *pgd);
138
139static inline bool __pte_access_permitted(pte_t pte, u64 prot)
140{
141 return (pte_val(pte) & (prot | _PAGE_SPECIAL)) == prot;
142}
143
144#ifdef CONFIG_X2TLB
145static inline bool pte_access_permitted(pte_t pte, bool write)
146{
147 u64 prot = _PAGE_PRESENT;
148
149 prot |= _PAGE_EXT(_PAGE_EXT_KERN_READ | _PAGE_EXT_USER_READ);
150 if (write)
151 prot |= _PAGE_EXT(_PAGE_EXT_KERN_WRITE | _PAGE_EXT_USER_WRITE);
152 return __pte_access_permitted(pte, prot);
153}
154#else
155static inline bool pte_access_permitted(pte_t pte, bool write)
156{
157 u64 prot = _PAGE_PRESENT | _PAGE_USER;
158
159 if (write)
160 prot |= _PAGE_RW;
161 return __pte_access_permitted(pte, prot);
162}
163#endif
164
165#define pte_access_permitted pte_access_permitted
166
167/* arch/sh/mm/mmap.c */
168#define HAVE_ARCH_UNMAPPED_AREA
169#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
170
171#endif /* __ASM_SH_PGTABLE_H */