Linux kernel mirror (for testing)
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1/*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Copyright 2003 PathScale, Inc.
4 * Derived from include/asm-i386/pgtable.h
5 * Licensed under the GPL
6 */
7
8#ifndef __UM_PGTABLE_H
9#define __UM_PGTABLE_H
10
11#include <asm/fixmap.h>
12
13#define _PAGE_PRESENT 0x001
14#define _PAGE_NEWPAGE 0x002
15#define _PAGE_NEWPROT 0x004
16#define _PAGE_RW 0x020
17#define _PAGE_USER 0x040
18#define _PAGE_ACCESSED 0x080
19#define _PAGE_DIRTY 0x100
20/* If _PAGE_PRESENT is clear, we use these: */
21#define _PAGE_FILE 0x008 /* nonlinear file mapping, saved PTE; unset:swap */
22#define _PAGE_PROTNONE 0x010 /* if the user mapped it with PROT_NONE;
23 pte_present gives true */
24
25#ifdef CONFIG_3_LEVEL_PGTABLES
26#include "asm/pgtable-3level.h"
27#else
28#include "asm/pgtable-2level.h"
29#endif
30
31extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
32
33/* zero page used for uninitialized stuff */
34extern unsigned long *empty_zero_page;
35
36#define pgtable_cache_init() do ; while (0)
37
38/* Just any arbitrary offset to the start of the vmalloc VM area: the
39 * current 8MB value just means that there will be a 8MB "hole" after the
40 * physical memory until the kernel virtual memory starts. That means that
41 * any out-of-bounds memory accesses will hopefully be caught.
42 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
43 * area for the same reason. ;)
44 */
45
46extern unsigned long end_iomem;
47
48#define VMALLOC_OFFSET (__va_space)
49#define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
50#ifdef CONFIG_HIGHMEM
51# define VMALLOC_END (PKMAP_BASE-2*PAGE_SIZE)
52#else
53# define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
54#endif
55
56#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
57#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
58#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
59
60#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
61#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
62#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
63#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
64#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
65
66/*
67 * The i386 can't do page protection for execute, and considers that the same
68 * are read.
69 * Also, write permissions imply read permissions. This is the closest we can
70 * get..
71 */
72#define __P000 PAGE_NONE
73#define __P001 PAGE_READONLY
74#define __P010 PAGE_COPY
75#define __P011 PAGE_COPY
76#define __P100 PAGE_READONLY
77#define __P101 PAGE_READONLY
78#define __P110 PAGE_COPY
79#define __P111 PAGE_COPY
80
81#define __S000 PAGE_NONE
82#define __S001 PAGE_READONLY
83#define __S010 PAGE_SHARED
84#define __S011 PAGE_SHARED
85#define __S100 PAGE_READONLY
86#define __S101 PAGE_READONLY
87#define __S110 PAGE_SHARED
88#define __S111 PAGE_SHARED
89
90/*
91 * ZERO_PAGE is a global shared page that is always zero: used
92 * for zero-mapped memory areas etc..
93 */
94#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
95
96#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
97
98#define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
99#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
100
101#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
102#define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
103
104#define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE)
105#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
106
107#define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE)
108#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
109
110#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
111
112#define pte_page(x) pfn_to_page(pte_pfn(x))
113
114#define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
115
116/*
117 * =================================
118 * Flags checking section.
119 * =================================
120 */
121
122static inline int pte_none(pte_t pte)
123{
124 return pte_is_zero(pte);
125}
126
127/*
128 * The following only work if pte_present() is true.
129 * Undefined behaviour if not..
130 */
131static inline int pte_read(pte_t pte)
132{
133 return((pte_get_bits(pte, _PAGE_USER)) &&
134 !(pte_get_bits(pte, _PAGE_PROTNONE)));
135}
136
137static inline int pte_exec(pte_t pte){
138 return((pte_get_bits(pte, _PAGE_USER)) &&
139 !(pte_get_bits(pte, _PAGE_PROTNONE)));
140}
141
142static inline int pte_write(pte_t pte)
143{
144 return((pte_get_bits(pte, _PAGE_RW)) &&
145 !(pte_get_bits(pte, _PAGE_PROTNONE)));
146}
147
148/*
149 * The following only works if pte_present() is not true.
150 */
151static inline int pte_file(pte_t pte)
152{
153 return pte_get_bits(pte, _PAGE_FILE);
154}
155
156static inline int pte_dirty(pte_t pte)
157{
158 return pte_get_bits(pte, _PAGE_DIRTY);
159}
160
161static inline int pte_young(pte_t pte)
162{
163 return pte_get_bits(pte, _PAGE_ACCESSED);
164}
165
166static inline int pte_newpage(pte_t pte)
167{
168 return pte_get_bits(pte, _PAGE_NEWPAGE);
169}
170
171static inline int pte_newprot(pte_t pte)
172{
173 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
174}
175
176static inline int pte_special(pte_t pte)
177{
178 return 0;
179}
180
181/*
182 * =================================
183 * Flags setting section.
184 * =================================
185 */
186
187static inline pte_t pte_mknewprot(pte_t pte)
188{
189 pte_set_bits(pte, _PAGE_NEWPROT);
190 return(pte);
191}
192
193static inline pte_t pte_mkclean(pte_t pte)
194{
195 pte_clear_bits(pte, _PAGE_DIRTY);
196 return(pte);
197}
198
199static inline pte_t pte_mkold(pte_t pte)
200{
201 pte_clear_bits(pte, _PAGE_ACCESSED);
202 return(pte);
203}
204
205static inline pte_t pte_wrprotect(pte_t pte)
206{
207 pte_clear_bits(pte, _PAGE_RW);
208 return(pte_mknewprot(pte));
209}
210
211static inline pte_t pte_mkread(pte_t pte)
212{
213 pte_set_bits(pte, _PAGE_USER);
214 return(pte_mknewprot(pte));
215}
216
217static inline pte_t pte_mkdirty(pte_t pte)
218{
219 pte_set_bits(pte, _PAGE_DIRTY);
220 return(pte);
221}
222
223static inline pte_t pte_mkyoung(pte_t pte)
224{
225 pte_set_bits(pte, _PAGE_ACCESSED);
226 return(pte);
227}
228
229static inline pte_t pte_mkwrite(pte_t pte)
230{
231 pte_set_bits(pte, _PAGE_RW);
232 return(pte_mknewprot(pte));
233}
234
235static inline pte_t pte_mkuptodate(pte_t pte)
236{
237 pte_clear_bits(pte, _PAGE_NEWPAGE);
238 if(pte_present(pte))
239 pte_clear_bits(pte, _PAGE_NEWPROT);
240 return(pte);
241}
242
243static inline pte_t pte_mknewpage(pte_t pte)
244{
245 pte_set_bits(pte, _PAGE_NEWPAGE);
246 return(pte);
247}
248
249static inline pte_t pte_mkspecial(pte_t pte)
250{
251 return(pte);
252}
253
254static inline void set_pte(pte_t *pteptr, pte_t pteval)
255{
256 pte_copy(*pteptr, pteval);
257
258 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
259 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to
260 * mapped pages.
261 */
262
263 *pteptr = pte_mknewpage(*pteptr);
264 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
265}
266#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
267
268/*
269 * Conversion functions: convert a page and protection to a page entry,
270 * and a page entry and page directory to the page they refer to.
271 */
272
273#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
274#define __virt_to_page(virt) phys_to_page(__pa(virt))
275#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
276#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
277
278#define mk_pte(page, pgprot) \
279 ({ pte_t pte; \
280 \
281 pte_set_val(pte, page_to_phys(page), (pgprot)); \
282 if (pte_present(pte)) \
283 pte_mknewprot(pte_mknewpage(pte)); \
284 pte;})
285
286static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
287{
288 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
289 return pte;
290}
291
292/*
293 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
294 *
295 * this macro returns the index of the entry in the pgd page which would
296 * control the given virtual address
297 */
298#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
299
300/*
301 * pgd_offset() returns a (pgd_t *)
302 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
303 */
304#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
305
306/*
307 * a shortcut which implies the use of the kernel's pgd, instead
308 * of a process's
309 */
310#define pgd_offset_k(address) pgd_offset(&init_mm, address)
311
312/*
313 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
314 *
315 * this macro returns the index of the entry in the pmd page which would
316 * control the given virtual address
317 */
318#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
319#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
320
321#define pmd_page_vaddr(pmd) \
322 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
323
324/*
325 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
326 *
327 * this macro returns the index of the entry in the pte page which would
328 * control the given virtual address
329 */
330#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
331#define pte_offset_kernel(dir, address) \
332 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
333#define pte_offset_map(dir, address) \
334 ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
335#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
336#define pte_unmap(pte) do { } while (0)
337#define pte_unmap_nested(pte) do { } while (0)
338
339struct mm_struct;
340extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
341
342#define update_mmu_cache(vma,address,pte) do ; while (0)
343
344/* Encode and de-code a swap entry */
345#define __swp_type(x) (((x).val >> 4) & 0x3f)
346#define __swp_offset(x) ((x).val >> 11)
347
348#define __swp_entry(type, offset) \
349 ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
350#define __pte_to_swp_entry(pte) \
351 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
352#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
353
354#define kern_addr_valid(addr) (1)
355
356#include <asm-generic/pgtable.h>
357
358#endif