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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 * Copyright 2003 PathScale, Inc.
5 * Derived from include/asm-i386/pgtable.h
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_PROTNONE 0x010 /* if the user mapped it with PROT_NONE;
22 pte_present gives true */
23
24#ifdef CONFIG_3_LEVEL_PGTABLES
25#include <asm/pgtable-3level.h>
26#else
27#include <asm/pgtable-2level.h>
28#endif
29
30extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
31
32/* zero page used for uninitialized stuff */
33extern unsigned long *empty_zero_page;
34
35/* Just any arbitrary offset to the start of the vmalloc VM area: the
36 * current 8MB value just means that there will be a 8MB "hole" after the
37 * physical memory until the kernel virtual memory starts. That means that
38 * any out-of-bounds memory accesses will hopefully be caught.
39 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
40 * area for the same reason. ;)
41 */
42
43extern unsigned long end_iomem;
44
45#define VMALLOC_OFFSET (__va_space)
46#define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
47#define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
48#define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
49#define MODULES_VADDR VMALLOC_START
50#define MODULES_END VMALLOC_END
51#define MODULES_LEN (MODULES_VADDR - MODULES_END)
52
53#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
54#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
55#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
56#define __PAGE_KERNEL_EXEC \
57 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
58#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
59#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
60#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
61#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
62#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
63#define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC)
64
65/*
66 * The i386 can't do page protection for execute, and considers that the same
67 * are read.
68 * Also, write permissions imply read permissions. This is the closest we can
69 * get..
70 */
71
72/*
73 * ZERO_PAGE is a global shared page that is always zero: used
74 * for zero-mapped memory areas etc..
75 */
76#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
77
78#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
79
80#define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
81#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
82
83#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
84#define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
85
86#define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE)
87#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
88
89#define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE)
90#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
91
92#define p4d_newpage(x) (p4d_val(x) & _PAGE_NEWPAGE)
93#define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE)
94
95#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
96#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
97
98#define pte_page(x) pfn_to_page(pte_pfn(x))
99
100#define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
101
102/*
103 * =================================
104 * Flags checking section.
105 * =================================
106 */
107
108static inline int pte_none(pte_t pte)
109{
110 return pte_is_zero(pte);
111}
112
113/*
114 * The following only work if pte_present() is true.
115 * Undefined behaviour if not..
116 */
117static inline int pte_read(pte_t pte)
118{
119 return((pte_get_bits(pte, _PAGE_USER)) &&
120 !(pte_get_bits(pte, _PAGE_PROTNONE)));
121}
122
123static inline int pte_exec(pte_t pte){
124 return((pte_get_bits(pte, _PAGE_USER)) &&
125 !(pte_get_bits(pte, _PAGE_PROTNONE)));
126}
127
128static inline int pte_write(pte_t pte)
129{
130 return((pte_get_bits(pte, _PAGE_RW)) &&
131 !(pte_get_bits(pte, _PAGE_PROTNONE)));
132}
133
134static inline int pte_dirty(pte_t pte)
135{
136 return pte_get_bits(pte, _PAGE_DIRTY);
137}
138
139static inline int pte_young(pte_t pte)
140{
141 return pte_get_bits(pte, _PAGE_ACCESSED);
142}
143
144static inline int pte_newpage(pte_t pte)
145{
146 return pte_get_bits(pte, _PAGE_NEWPAGE);
147}
148
149static inline int pte_newprot(pte_t pte)
150{
151 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
152}
153
154/*
155 * =================================
156 * Flags setting section.
157 * =================================
158 */
159
160static inline pte_t pte_mknewprot(pte_t pte)
161{
162 pte_set_bits(pte, _PAGE_NEWPROT);
163 return(pte);
164}
165
166static inline pte_t pte_mkclean(pte_t pte)
167{
168 pte_clear_bits(pte, _PAGE_DIRTY);
169 return(pte);
170}
171
172static inline pte_t pte_mkold(pte_t pte)
173{
174 pte_clear_bits(pte, _PAGE_ACCESSED);
175 return(pte);
176}
177
178static inline pte_t pte_wrprotect(pte_t pte)
179{
180 if (likely(pte_get_bits(pte, _PAGE_RW)))
181 pte_clear_bits(pte, _PAGE_RW);
182 else
183 return pte;
184 return(pte_mknewprot(pte));
185}
186
187static inline pte_t pte_mkread(pte_t pte)
188{
189 if (unlikely(pte_get_bits(pte, _PAGE_USER)))
190 return pte;
191 pte_set_bits(pte, _PAGE_USER);
192 return(pte_mknewprot(pte));
193}
194
195static inline pte_t pte_mkdirty(pte_t pte)
196{
197 pte_set_bits(pte, _PAGE_DIRTY);
198 return(pte);
199}
200
201static inline pte_t pte_mkyoung(pte_t pte)
202{
203 pte_set_bits(pte, _PAGE_ACCESSED);
204 return(pte);
205}
206
207static inline pte_t pte_mkwrite(pte_t pte)
208{
209 if (unlikely(pte_get_bits(pte, _PAGE_RW)))
210 return pte;
211 pte_set_bits(pte, _PAGE_RW);
212 return(pte_mknewprot(pte));
213}
214
215static inline pte_t pte_mkuptodate(pte_t pte)
216{
217 pte_clear_bits(pte, _PAGE_NEWPAGE);
218 if(pte_present(pte))
219 pte_clear_bits(pte, _PAGE_NEWPROT);
220 return(pte);
221}
222
223static inline pte_t pte_mknewpage(pte_t pte)
224{
225 pte_set_bits(pte, _PAGE_NEWPAGE);
226 return(pte);
227}
228
229static inline void set_pte(pte_t *pteptr, pte_t pteval)
230{
231 pte_copy(*pteptr, pteval);
232
233 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
234 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to
235 * mapped pages.
236 */
237
238 *pteptr = pte_mknewpage(*pteptr);
239 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
240}
241
242static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
243 pte_t *pteptr, pte_t pteval)
244{
245 set_pte(pteptr, pteval);
246}
247
248#define __HAVE_ARCH_PTE_SAME
249static inline int pte_same(pte_t pte_a, pte_t pte_b)
250{
251 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
252}
253
254/*
255 * Conversion functions: convert a page and protection to a page entry,
256 * and a page entry and page directory to the page they refer to.
257 */
258
259#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
260#define __virt_to_page(virt) phys_to_page(__pa(virt))
261#define page_to_phys(page) pfn_to_phys(page_to_pfn(page))
262#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
263
264#define mk_pte(page, pgprot) \
265 ({ pte_t pte; \
266 \
267 pte_set_val(pte, page_to_phys(page), (pgprot)); \
268 if (pte_present(pte)) \
269 pte_mknewprot(pte_mknewpage(pte)); \
270 pte;})
271
272static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
273{
274 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
275 return pte;
276}
277
278/*
279 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
280 *
281 * this macro returns the index of the entry in the pmd page which would
282 * control the given virtual address
283 */
284#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
285
286struct mm_struct;
287extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
288
289#define update_mmu_cache(vma,address,ptep) do {} while (0)
290
291/* Encode and de-code a swap entry */
292#define __swp_type(x) (((x).val >> 5) & 0x1f)
293#define __swp_offset(x) ((x).val >> 11)
294
295#define __swp_entry(type, offset) \
296 ((swp_entry_t) { ((type) << 5) | ((offset) << 11) })
297#define __pte_to_swp_entry(pte) \
298 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
299#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
300
301/* Clear a kernel PTE and flush it from the TLB */
302#define kpte_clear_flush(ptep, vaddr) \
303do { \
304 pte_clear(&init_mm, (vaddr), (ptep)); \
305 __flush_tlb_one((vaddr)); \
306} while (0)
307
308#endif
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#define MODULES_VADDR VMALLOC_START
57#define MODULES_END VMALLOC_END
58#define MODULES_LEN (MODULES_VADDR - MODULES_END)
59
60#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
61#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
62#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
63#define __PAGE_KERNEL_EXEC \
64 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
65#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
66#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
67#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
68#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
69#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
70#define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC)
71
72/*
73 * The i386 can't do page protection for execute, and considers that the same
74 * are read.
75 * Also, write permissions imply read permissions. This is the closest we can
76 * get..
77 */
78#define __P000 PAGE_NONE
79#define __P001 PAGE_READONLY
80#define __P010 PAGE_COPY
81#define __P011 PAGE_COPY
82#define __P100 PAGE_READONLY
83#define __P101 PAGE_READONLY
84#define __P110 PAGE_COPY
85#define __P111 PAGE_COPY
86
87#define __S000 PAGE_NONE
88#define __S001 PAGE_READONLY
89#define __S010 PAGE_SHARED
90#define __S011 PAGE_SHARED
91#define __S100 PAGE_READONLY
92#define __S101 PAGE_READONLY
93#define __S110 PAGE_SHARED
94#define __S111 PAGE_SHARED
95
96/*
97 * ZERO_PAGE is a global shared page that is always zero: used
98 * for zero-mapped memory areas etc..
99 */
100#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
101
102#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
103
104#define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
105#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
106
107#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
108#define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
109
110#define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE)
111#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
112
113#define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE)
114#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
115
116#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
117
118#define pte_page(x) pfn_to_page(pte_pfn(x))
119
120#define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
121
122/*
123 * =================================
124 * Flags checking section.
125 * =================================
126 */
127
128static inline int pte_none(pte_t pte)
129{
130 return pte_is_zero(pte);
131}
132
133/*
134 * The following only work if pte_present() is true.
135 * Undefined behaviour if not..
136 */
137static inline int pte_read(pte_t pte)
138{
139 return((pte_get_bits(pte, _PAGE_USER)) &&
140 !(pte_get_bits(pte, _PAGE_PROTNONE)));
141}
142
143static inline int pte_exec(pte_t pte){
144 return((pte_get_bits(pte, _PAGE_USER)) &&
145 !(pte_get_bits(pte, _PAGE_PROTNONE)));
146}
147
148static inline int pte_write(pte_t pte)
149{
150 return((pte_get_bits(pte, _PAGE_RW)) &&
151 !(pte_get_bits(pte, _PAGE_PROTNONE)));
152}
153
154/*
155 * The following only works if pte_present() is not true.
156 */
157static inline int pte_file(pte_t pte)
158{
159 return pte_get_bits(pte, _PAGE_FILE);
160}
161
162static inline int pte_dirty(pte_t pte)
163{
164 return pte_get_bits(pte, _PAGE_DIRTY);
165}
166
167static inline int pte_young(pte_t pte)
168{
169 return pte_get_bits(pte, _PAGE_ACCESSED);
170}
171
172static inline int pte_newpage(pte_t pte)
173{
174 return pte_get_bits(pte, _PAGE_NEWPAGE);
175}
176
177static inline int pte_newprot(pte_t pte)
178{
179 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
180}
181
182static inline int pte_special(pte_t pte)
183{
184 return 0;
185}
186
187/*
188 * =================================
189 * Flags setting section.
190 * =================================
191 */
192
193static inline pte_t pte_mknewprot(pte_t pte)
194{
195 pte_set_bits(pte, _PAGE_NEWPROT);
196 return(pte);
197}
198
199static inline pte_t pte_mkclean(pte_t pte)
200{
201 pte_clear_bits(pte, _PAGE_DIRTY);
202 return(pte);
203}
204
205static inline pte_t pte_mkold(pte_t pte)
206{
207 pte_clear_bits(pte, _PAGE_ACCESSED);
208 return(pte);
209}
210
211static inline pte_t pte_wrprotect(pte_t pte)
212{
213 pte_clear_bits(pte, _PAGE_RW);
214 return(pte_mknewprot(pte));
215}
216
217static inline pte_t pte_mkread(pte_t pte)
218{
219 pte_set_bits(pte, _PAGE_USER);
220 return(pte_mknewprot(pte));
221}
222
223static inline pte_t pte_mkdirty(pte_t pte)
224{
225 pte_set_bits(pte, _PAGE_DIRTY);
226 return(pte);
227}
228
229static inline pte_t pte_mkyoung(pte_t pte)
230{
231 pte_set_bits(pte, _PAGE_ACCESSED);
232 return(pte);
233}
234
235static inline pte_t pte_mkwrite(pte_t pte)
236{
237 pte_set_bits(pte, _PAGE_RW);
238 return(pte_mknewprot(pte));
239}
240
241static inline pte_t pte_mkuptodate(pte_t pte)
242{
243 pte_clear_bits(pte, _PAGE_NEWPAGE);
244 if(pte_present(pte))
245 pte_clear_bits(pte, _PAGE_NEWPROT);
246 return(pte);
247}
248
249static inline pte_t pte_mknewpage(pte_t pte)
250{
251 pte_set_bits(pte, _PAGE_NEWPAGE);
252 return(pte);
253}
254
255static inline pte_t pte_mkspecial(pte_t pte)
256{
257 return(pte);
258}
259
260static inline void set_pte(pte_t *pteptr, pte_t pteval)
261{
262 pte_copy(*pteptr, pteval);
263
264 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
265 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to
266 * mapped pages.
267 */
268
269 *pteptr = pte_mknewpage(*pteptr);
270 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
271}
272#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
273
274#define __HAVE_ARCH_PTE_SAME
275static inline int pte_same(pte_t pte_a, pte_t pte_b)
276{
277 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
278}
279
280/*
281 * Conversion functions: convert a page and protection to a page entry,
282 * and a page entry and page directory to the page they refer to.
283 */
284
285#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
286#define __virt_to_page(virt) phys_to_page(__pa(virt))
287#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
288#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
289
290#define mk_pte(page, pgprot) \
291 ({ pte_t pte; \
292 \
293 pte_set_val(pte, page_to_phys(page), (pgprot)); \
294 if (pte_present(pte)) \
295 pte_mknewprot(pte_mknewpage(pte)); \
296 pte;})
297
298static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
299{
300 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
301 return pte;
302}
303
304/*
305 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
306 *
307 * this macro returns the index of the entry in the pgd page which would
308 * control the given virtual address
309 */
310#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
311
312/*
313 * pgd_offset() returns a (pgd_t *)
314 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
315 */
316#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
317
318/*
319 * a shortcut which implies the use of the kernel's pgd, instead
320 * of a process's
321 */
322#define pgd_offset_k(address) pgd_offset(&init_mm, address)
323
324/*
325 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
326 *
327 * this macro returns the index of the entry in the pmd page which would
328 * control the given virtual address
329 */
330#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
331#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
332
333#define pmd_page_vaddr(pmd) \
334 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
335
336/*
337 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
338 *
339 * this macro returns the index of the entry in the pte page which would
340 * control the given virtual address
341 */
342#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
343#define pte_offset_kernel(dir, address) \
344 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
345#define pte_offset_map(dir, address) \
346 ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
347#define pte_unmap(pte) do { } while (0)
348
349struct mm_struct;
350extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
351
352#define update_mmu_cache(vma,address,ptep) do ; while (0)
353
354/* Encode and de-code a swap entry */
355#define __swp_type(x) (((x).val >> 5) & 0x1f)
356#define __swp_offset(x) ((x).val >> 11)
357
358#define __swp_entry(type, offset) \
359 ((swp_entry_t) { ((type) << 5) | ((offset) << 11) })
360#define __pte_to_swp_entry(pte) \
361 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
362#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
363
364#define kern_addr_valid(addr) (1)
365
366#include <asm-generic/pgtable.h>
367
368/* Clear a kernel PTE and flush it from the TLB */
369#define kpte_clear_flush(ptep, vaddr) \
370do { \
371 pte_clear(&init_mm, (vaddr), (ptep)); \
372 __flush_tlb_one((vaddr)); \
373} while (0)
374
375#endif