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#define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
51#ifdef CONFIG_HIGHMEM
52# define VMALLOC_END (PKMAP_BASE-2*PAGE_SIZE)
53#else
54# define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
55#endif
56
57#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
58#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
59#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
60
61#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
62#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
63#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
64#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
65#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
66
67/*
68 * The i386 can't do page protection for execute, and considers that the same
69 * are read.
70 * Also, write permissions imply read permissions. This is the closest we can
71 * get..
72 */
73#define __P000 PAGE_NONE
74#define __P001 PAGE_READONLY
75#define __P010 PAGE_COPY
76#define __P011 PAGE_COPY
77#define __P100 PAGE_READONLY
78#define __P101 PAGE_READONLY
79#define __P110 PAGE_COPY
80#define __P111 PAGE_COPY
81
82#define __S000 PAGE_NONE
83#define __S001 PAGE_READONLY
84#define __S010 PAGE_SHARED
85#define __S011 PAGE_SHARED
86#define __S100 PAGE_READONLY
87#define __S101 PAGE_READONLY
88#define __S110 PAGE_SHARED
89#define __S111 PAGE_SHARED
90
91/*
92 * ZERO_PAGE is a global shared page that is always zero: used
93 * for zero-mapped memory areas etc..
94 */
95#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
96
97#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
98
99#define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
100#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
101
102#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
103#define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
104
105#define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE)
106#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
107
108#define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE)
109#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
110
111#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
112
113#define pte_page(x) pfn_to_page(pte_pfn(x))
114
115#define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
116
117/*
118 * =================================
119 * Flags checking section.
120 * =================================
121 */
122
123static inline int pte_none(pte_t pte)
124{
125 return pte_is_zero(pte);
126}
127
128/*
129 * The following only work if pte_present() is true.
130 * Undefined behaviour if not..
131 */
132static inline int pte_read(pte_t pte)
133{
134 return((pte_get_bits(pte, _PAGE_USER)) &&
135 !(pte_get_bits(pte, _PAGE_PROTNONE)));
136}
137
138static inline int pte_exec(pte_t pte){
139 return((pte_get_bits(pte, _PAGE_USER)) &&
140 !(pte_get_bits(pte, _PAGE_PROTNONE)));
141}
142
143static inline int pte_write(pte_t pte)
144{
145 return((pte_get_bits(pte, _PAGE_RW)) &&
146 !(pte_get_bits(pte, _PAGE_PROTNONE)));
147}
148
149/*
150 * The following only works if pte_present() is not true.
151 */
152static inline int pte_file(pte_t pte)
153{
154 return pte_get_bits(pte, _PAGE_FILE);
155}
156
157static inline int pte_dirty(pte_t pte)
158{
159 return pte_get_bits(pte, _PAGE_DIRTY);
160}
161
162static inline int pte_young(pte_t pte)
163{
164 return pte_get_bits(pte, _PAGE_ACCESSED);
165}
166
167static inline int pte_newpage(pte_t pte)
168{
169 return pte_get_bits(pte, _PAGE_NEWPAGE);
170}
171
172static inline int pte_newprot(pte_t pte)
173{
174 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
175}
176
177static inline int pte_special(pte_t pte)
178{
179 return 0;
180}
181
182/*
183 * =================================
184 * Flags setting section.
185 * =================================
186 */
187
188static inline pte_t pte_mknewprot(pte_t pte)
189{
190 pte_set_bits(pte, _PAGE_NEWPROT);
191 return(pte);
192}
193
194static inline pte_t pte_mkclean(pte_t pte)
195{
196 pte_clear_bits(pte, _PAGE_DIRTY);
197 return(pte);
198}
199
200static inline pte_t pte_mkold(pte_t pte)
201{
202 pte_clear_bits(pte, _PAGE_ACCESSED);
203 return(pte);
204}
205
206static inline pte_t pte_wrprotect(pte_t pte)
207{
208 pte_clear_bits(pte, _PAGE_RW);
209 return(pte_mknewprot(pte));
210}
211
212static inline pte_t pte_mkread(pte_t pte)
213{
214 pte_set_bits(pte, _PAGE_USER);
215 return(pte_mknewprot(pte));
216}
217
218static inline pte_t pte_mkdirty(pte_t pte)
219{
220 pte_set_bits(pte, _PAGE_DIRTY);
221 return(pte);
222}
223
224static inline pte_t pte_mkyoung(pte_t pte)
225{
226 pte_set_bits(pte, _PAGE_ACCESSED);
227 return(pte);
228}
229
230static inline pte_t pte_mkwrite(pte_t pte)
231{
232 pte_set_bits(pte, _PAGE_RW);
233 return(pte_mknewprot(pte));
234}
235
236static inline pte_t pte_mkuptodate(pte_t pte)
237{
238 pte_clear_bits(pte, _PAGE_NEWPAGE);
239 if(pte_present(pte))
240 pte_clear_bits(pte, _PAGE_NEWPROT);
241 return(pte);
242}
243
244static inline pte_t pte_mknewpage(pte_t pte)
245{
246 pte_set_bits(pte, _PAGE_NEWPAGE);
247 return(pte);
248}
249
250static inline pte_t pte_mkspecial(pte_t pte)
251{
252 return(pte);
253}
254
255static inline void set_pte(pte_t *pteptr, pte_t pteval)
256{
257 pte_copy(*pteptr, pteval);
258
259 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
260 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to
261 * mapped pages.
262 */
263
264 *pteptr = pte_mknewpage(*pteptr);
265 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
266}
267#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
268
269/*
270 * Conversion functions: convert a page and protection to a page entry,
271 * and a page entry and page directory to the page they refer to.
272 */
273
274#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
275#define __virt_to_page(virt) phys_to_page(__pa(virt))
276#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
277#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
278
279#define mk_pte(page, pgprot) \
280 ({ pte_t pte; \
281 \
282 pte_set_val(pte, page_to_phys(page), (pgprot)); \
283 if (pte_present(pte)) \
284 pte_mknewprot(pte_mknewpage(pte)); \
285 pte;})
286
287static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
288{
289 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
290 return pte;
291}
292
293/*
294 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
295 *
296 * this macro returns the index of the entry in the pgd page which would
297 * control the given virtual address
298 */
299#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
300
301/*
302 * pgd_offset() returns a (pgd_t *)
303 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
304 */
305#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
306
307/*
308 * a shortcut which implies the use of the kernel's pgd, instead
309 * of a process's
310 */
311#define pgd_offset_k(address) pgd_offset(&init_mm, address)
312
313/*
314 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
315 *
316 * this macro returns the index of the entry in the pmd page which would
317 * control the given virtual address
318 */
319#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
320#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
321
322#define pmd_page_vaddr(pmd) \
323 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
324
325/*
326 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
327 *
328 * this macro returns the index of the entry in the pte page which would
329 * control the given virtual address
330 */
331#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
332#define pte_offset_kernel(dir, address) \
333 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
334#define pte_offset_map(dir, address) \
335 ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
336#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
337#define pte_unmap(pte) do { } while (0)
338#define pte_unmap_nested(pte) do { } while (0)
339
340struct mm_struct;
341extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
342
343#define update_mmu_cache(vma,address,pte) do ; while (0)
344
345/* Encode and de-code a swap entry */
346#define __swp_type(x) (((x).val >> 4) & 0x3f)
347#define __swp_offset(x) ((x).val >> 11)
348
349#define __swp_entry(type, offset) \
350 ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
351#define __pte_to_swp_entry(pte) \
352 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
353#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
354
355#define kern_addr_valid(addr) (1)
356
357#include <asm-generic/pgtable.h>
358
359/* Clear a kernel PTE and flush it from the TLB */
360#define kpte_clear_flush(ptep, vaddr) \
361do { \
362 pte_clear(&init_mm, (vaddr), (ptep)); \
363 __flush_tlb_one((vaddr)); \
364} while (0)
365
366#endif