Linux kernel mirror (for testing)
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1/*
2 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
3 * Copyright (C) 2009 Wind River Systems Inc
4 *
5 * Based on asm/pgtable-32.h from mips which is:
6 *
7 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
8 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
9 *
10 * This file is subject to the terms and conditions of the GNU General Public
11 * License. See the file "COPYING" in the main directory of this archive
12 * for more details.
13 */
14
15#ifndef _ASM_NIOS2_PGTABLE_H
16#define _ASM_NIOS2_PGTABLE_H
17
18#include <linux/io.h>
19#include <linux/bug.h>
20#include <asm/page.h>
21#include <asm/cacheflush.h>
22#include <asm/tlbflush.h>
23
24#include <asm/pgtable-bits.h>
25#include <asm-generic/pgtable-nopmd.h>
26
27#define VMALLOC_START CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
28#define VMALLOC_END (CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
29
30struct mm_struct;
31
32/* Helper macro */
33#define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED | \
34 ((x) ? _PAGE_EXEC : 0) | \
35 ((r) ? _PAGE_READ : 0) | \
36 ((w) ? _PAGE_WRITE : 0))
37/*
38 * These are the macros that generic kernel code needs
39 * (to populate protection_map[])
40 */
41
42/* Remove W bit on private pages for COW support */
43
44/* Shared pages can have exact HW mapping */
45
46/* Used all over the kernel */
47#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
48 _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL)
49
50#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
51 _PAGE_WRITE | _PAGE_ACCESSED)
52
53#define PAGE_COPY MKP(0, 0, 1)
54
55#define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t))
56#define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t))
57
58#define USER_PTRS_PER_PGD \
59 (CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE)
60
61#define PGDIR_SHIFT 22
62#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
63#define PGDIR_MASK (~(PGDIR_SIZE-1))
64
65/*
66 * ZERO_PAGE is a global shared page that is always zero: used
67 * for zero-mapped memory areas etc..
68 */
69extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
70#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
71
72extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
73extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
74
75/*
76 * (pmds are folded into puds so this doesn't get actually called,
77 * but the define is needed for a generic inline function.)
78 */
79static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval)
80{
81 *pmdptr = pmdval;
82}
83
84static inline int pte_write(pte_t pte) \
85 { return pte_val(pte) & _PAGE_WRITE; }
86static inline int pte_dirty(pte_t pte) \
87 { return pte_val(pte) & _PAGE_DIRTY; }
88static inline int pte_young(pte_t pte) \
89 { return pte_val(pte) & _PAGE_ACCESSED; }
90
91#define pgprot_noncached pgprot_noncached
92
93static inline pgprot_t pgprot_noncached(pgprot_t _prot)
94{
95 unsigned long prot = pgprot_val(_prot);
96
97 prot &= ~_PAGE_CACHED;
98
99 return __pgprot(prot);
100}
101
102static inline int pte_none(pte_t pte)
103{
104 return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf));
105}
106
107static inline int pte_present(pte_t pte) \
108 { return pte_val(pte) & _PAGE_PRESENT; }
109
110/*
111 * The following only work if pte_present() is true.
112 * Undefined behaviour if not..
113 */
114static inline pte_t pte_wrprotect(pte_t pte)
115{
116 pte_val(pte) &= ~_PAGE_WRITE;
117 return pte;
118}
119
120static inline pte_t pte_mkclean(pte_t pte)
121{
122 pte_val(pte) &= ~_PAGE_DIRTY;
123 return pte;
124}
125
126static inline pte_t pte_mkold(pte_t pte)
127{
128 pte_val(pte) &= ~_PAGE_ACCESSED;
129 return pte;
130}
131
132static inline pte_t pte_mkwrite_novma(pte_t pte)
133{
134 pte_val(pte) |= _PAGE_WRITE;
135 return pte;
136}
137
138static inline pte_t pte_mkdirty(pte_t pte)
139{
140 pte_val(pte) |= _PAGE_DIRTY;
141 return pte;
142}
143
144static inline pte_t pte_mkyoung(pte_t pte)
145{
146 pte_val(pte) |= _PAGE_ACCESSED;
147 return pte;
148}
149
150static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
151{
152 const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC;
153
154 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
155 return pte;
156}
157
158static inline int pmd_present(pmd_t pmd)
159{
160 return (pmd_val(pmd) != (unsigned long) invalid_pte_table)
161 && (pmd_val(pmd) != 0UL);
162}
163
164static inline void pmd_clear(pmd_t *pmdp)
165{
166 pmd_val(*pmdp) = (unsigned long) invalid_pte_table;
167}
168
169#define pte_pfn(pte) (pte_val(pte) & 0xfffff)
170#define pfn_pte(pfn, prot) (__pte(pfn | pgprot_val(prot)))
171#define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
172
173/*
174 * Store a linux PTE into the linux page table.
175 */
176static inline void set_pte(pte_t *ptep, pte_t pteval)
177{
178 *ptep = pteval;
179}
180
181static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
182 pte_t *ptep, pte_t pte, unsigned int nr)
183{
184 unsigned long paddr = (unsigned long)page_to_virt(pte_page(pte));
185
186 flush_dcache_range(paddr, paddr + nr * PAGE_SIZE);
187 for (;;) {
188 set_pte(ptep, pte);
189 if (--nr == 0)
190 break;
191 ptep++;
192 pte_val(pte) += 1;
193 }
194}
195#define set_ptes set_ptes
196
197static inline int pmd_none(pmd_t pmd)
198{
199 return (pmd_val(pmd) ==
200 (unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL);
201}
202
203#define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK)
204
205static inline void pte_clear(struct mm_struct *mm,
206 unsigned long addr, pte_t *ptep)
207{
208 pte_t null;
209
210 pte_val(null) = (addr >> PAGE_SHIFT) & 0xf;
211
212 set_pte(ptep, null);
213}
214
215/*
216 * Conversion functions: convert a page and protection to a page entry,
217 * and a page entry and page directory to the page they refer to.
218 */
219#define mk_pte(page, prot) (pfn_pte(page_to_pfn(page), prot))
220
221/*
222 * Conversion functions: convert a page and protection to a page entry,
223 * and a page entry and page directory to the page they refer to.
224 */
225#define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd))
226#define pmd_pfn(pmd) (pmd_phys(pmd) >> PAGE_SHIFT)
227#define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
228
229static inline unsigned long pmd_page_vaddr(pmd_t pmd)
230{
231 return pmd_val(pmd);
232}
233
234#define pte_ERROR(e) \
235 pr_err("%s:%d: bad pte %08lx.\n", \
236 __FILE__, __LINE__, pte_val(e))
237#define pgd_ERROR(e) \
238 pr_err("%s:%d: bad pgd %08lx.\n", \
239 __FILE__, __LINE__, pgd_val(e))
240
241/*
242 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
243 * are !pte_none() && !pte_present().
244 *
245 * Format of swap PTEs:
246 *
247 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
248 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
249 * E < type -> 0 0 0 0 0 0 <-------------- offset --------------->
250 *
251 * E is the exclusive marker that is not stored in swap entries.
252 *
253 * Note that the offset field is always non-zero if the swap type is 0, thus
254 * !pte_none() is always true.
255 */
256#define __swp_type(swp) (((swp).val >> 26) & 0x1f)
257#define __swp_offset(swp) ((swp).val & 0xfffff)
258#define __swp_entry(type, off) ((swp_entry_t) { (((type) & 0x1f) << 26) \
259 | ((off) & 0xfffff) })
260#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
261#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
262
263static inline int pte_swp_exclusive(pte_t pte)
264{
265 return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
266}
267
268static inline pte_t pte_swp_mkexclusive(pte_t pte)
269{
270 pte_val(pte) |= _PAGE_SWP_EXCLUSIVE;
271 return pte;
272}
273
274static inline pte_t pte_swp_clear_exclusive(pte_t pte)
275{
276 pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE;
277 return pte;
278}
279
280extern void __init paging_init(void);
281extern void __init mmu_init(void);
282
283void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma,
284 unsigned long address, pte_t *ptep, unsigned int nr);
285
286#define update_mmu_cache(vma, addr, ptep) \
287 update_mmu_cache_range(NULL, vma, addr, ptep, 1)
288
289#endif /* _ASM_NIOS2_PGTABLE_H */