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
30 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
31
32 /* zero page used for uninitialized stuff */
33 extern 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
43 extern 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 #define __P000 PAGE_NONE
72 #define __P001 PAGE_READONLY
73 #define __P010 PAGE_COPY
74 #define __P011 PAGE_COPY
75 #define __P100 PAGE_READONLY
76 #define __P101 PAGE_READONLY
77 #define __P110 PAGE_COPY
78 #define __P111 PAGE_COPY
79
80 #define __S000 PAGE_NONE
81 #define __S001 PAGE_READONLY
82 #define __S010 PAGE_SHARED
83 #define __S011 PAGE_SHARED
84 #define __S100 PAGE_READONLY
85 #define __S101 PAGE_READONLY
86 #define __S110 PAGE_SHARED
87 #define __S111 PAGE_SHARED
88
89 /*
90 * ZERO_PAGE is a global shared page that is always zero: used
91 * for zero-mapped memory areas etc..
92 */
93 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
94
95 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
96
97 #define pmd_none(x) (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
98 #define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
99
100 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
101 #define pmd_clear(xp) do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
102
103 #define pmd_newpage(x) (pmd_val(x) & _PAGE_NEWPAGE)
104 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
105
106 #define pud_newpage(x) (pud_val(x) & _PAGE_NEWPAGE)
107 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
108
109 #define p4d_newpage(x) (p4d_val(x) & _PAGE_NEWPAGE)
110 #define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE)
111
112 #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
113 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
114
115 #define pte_page(x) pfn_to_page(pte_pfn(x))
116
117 #define pte_present(x) pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
118
119 /*
120 * =================================
121 * Flags checking section.
122 * =================================
123 */
124
pte_none(pte_t pte)125 static inline int pte_none(pte_t pte)
126 {
127 return pte_is_zero(pte);
128 }
129
130 /*
131 * The following only work if pte_present() is true.
132 * Undefined behaviour if not..
133 */
pte_read(pte_t pte)134 static inline int pte_read(pte_t pte)
135 {
136 return((pte_get_bits(pte, _PAGE_USER)) &&
137 !(pte_get_bits(pte, _PAGE_PROTNONE)));
138 }
139
pte_exec(pte_t pte)140 static inline int pte_exec(pte_t pte){
141 return((pte_get_bits(pte, _PAGE_USER)) &&
142 !(pte_get_bits(pte, _PAGE_PROTNONE)));
143 }
144
pte_write(pte_t pte)145 static inline int pte_write(pte_t pte)
146 {
147 return((pte_get_bits(pte, _PAGE_RW)) &&
148 !(pte_get_bits(pte, _PAGE_PROTNONE)));
149 }
150
pte_dirty(pte_t pte)151 static inline int pte_dirty(pte_t pte)
152 {
153 return pte_get_bits(pte, _PAGE_DIRTY);
154 }
155
pte_young(pte_t pte)156 static inline int pte_young(pte_t pte)
157 {
158 return pte_get_bits(pte, _PAGE_ACCESSED);
159 }
160
pte_newpage(pte_t pte)161 static inline int pte_newpage(pte_t pte)
162 {
163 return pte_get_bits(pte, _PAGE_NEWPAGE);
164 }
165
pte_newprot(pte_t pte)166 static inline int pte_newprot(pte_t pte)
167 {
168 return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
169 }
170
171 /*
172 * =================================
173 * Flags setting section.
174 * =================================
175 */
176
pte_mknewprot(pte_t pte)177 static inline pte_t pte_mknewprot(pte_t pte)
178 {
179 pte_set_bits(pte, _PAGE_NEWPROT);
180 return(pte);
181 }
182
pte_mkclean(pte_t pte)183 static inline pte_t pte_mkclean(pte_t pte)
184 {
185 pte_clear_bits(pte, _PAGE_DIRTY);
186 return(pte);
187 }
188
pte_mkold(pte_t pte)189 static inline pte_t pte_mkold(pte_t pte)
190 {
191 pte_clear_bits(pte, _PAGE_ACCESSED);
192 return(pte);
193 }
194
pte_wrprotect(pte_t pte)195 static inline pte_t pte_wrprotect(pte_t pte)
196 {
197 if (likely(pte_get_bits(pte, _PAGE_RW)))
198 pte_clear_bits(pte, _PAGE_RW);
199 else
200 return pte;
201 return(pte_mknewprot(pte));
202 }
203
pte_mkread(pte_t pte)204 static inline pte_t pte_mkread(pte_t pte)
205 {
206 if (unlikely(pte_get_bits(pte, _PAGE_USER)))
207 return pte;
208 pte_set_bits(pte, _PAGE_USER);
209 return(pte_mknewprot(pte));
210 }
211
pte_mkdirty(pte_t pte)212 static inline pte_t pte_mkdirty(pte_t pte)
213 {
214 pte_set_bits(pte, _PAGE_DIRTY);
215 return(pte);
216 }
217
pte_mkyoung(pte_t pte)218 static inline pte_t pte_mkyoung(pte_t pte)
219 {
220 pte_set_bits(pte, _PAGE_ACCESSED);
221 return(pte);
222 }
223
pte_mkwrite(pte_t pte)224 static inline pte_t pte_mkwrite(pte_t pte)
225 {
226 if (unlikely(pte_get_bits(pte, _PAGE_RW)))
227 return pte;
228 pte_set_bits(pte, _PAGE_RW);
229 return(pte_mknewprot(pte));
230 }
231
pte_mkuptodate(pte_t pte)232 static inline pte_t pte_mkuptodate(pte_t pte)
233 {
234 pte_clear_bits(pte, _PAGE_NEWPAGE);
235 if(pte_present(pte))
236 pte_clear_bits(pte, _PAGE_NEWPROT);
237 return(pte);
238 }
239
pte_mknewpage(pte_t pte)240 static inline pte_t pte_mknewpage(pte_t pte)
241 {
242 pte_set_bits(pte, _PAGE_NEWPAGE);
243 return(pte);
244 }
245
set_pte(pte_t * pteptr,pte_t pteval)246 static inline void set_pte(pte_t *pteptr, pte_t pteval)
247 {
248 pte_copy(*pteptr, pteval);
249
250 /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
251 * fix_range knows to unmap it. _PAGE_NEWPROT is specific to
252 * mapped pages.
253 */
254
255 *pteptr = pte_mknewpage(*pteptr);
256 if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
257 }
258
set_pte_at(struct mm_struct * mm,unsigned long addr,pte_t * pteptr,pte_t pteval)259 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
260 pte_t *pteptr, pte_t pteval)
261 {
262 set_pte(pteptr, pteval);
263 }
264
265 #define __HAVE_ARCH_PTE_SAME
pte_same(pte_t pte_a,pte_t pte_b)266 static inline int pte_same(pte_t pte_a, pte_t pte_b)
267 {
268 return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
269 }
270
271 /*
272 * Conversion functions: convert a page and protection to a page entry,
273 * and a page entry and page directory to the page they refer to.
274 */
275
276 #define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
277 #define __virt_to_page(virt) phys_to_page(__pa(virt))
278 #define page_to_phys(page) pfn_to_phys(page_to_pfn(page))
279 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
280
281 #define mk_pte(page, pgprot) \
282 ({ pte_t pte; \
283 \
284 pte_set_val(pte, page_to_phys(page), (pgprot)); \
285 if (pte_present(pte)) \
286 pte_mknewprot(pte_mknewpage(pte)); \
287 pte;})
288
pte_modify(pte_t pte,pgprot_t newprot)289 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
290 {
291 pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
292 return pte;
293 }
294
295 /*
296 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
297 *
298 * this macro returns the index of the entry in the pmd page which would
299 * control the given virtual address
300 */
301 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
302
303 struct mm_struct;
304 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
305
306 #define update_mmu_cache(vma,address,ptep) do {} while (0)
307
308 /* Encode and de-code a swap entry */
309 #define __swp_type(x) (((x).val >> 5) & 0x1f)
310 #define __swp_offset(x) ((x).val >> 11)
311
312 #define __swp_entry(type, offset) \
313 ((swp_entry_t) { ((type) << 5) | ((offset) << 11) })
314 #define __pte_to_swp_entry(pte) \
315 ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
316 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
317
318 #define kern_addr_valid(addr) (1)
319
320 /* Clear a kernel PTE and flush it from the TLB */
321 #define kpte_clear_flush(ptep, vaddr) \
322 do { \
323 pte_clear(&init_mm, (vaddr), (ptep)); \
324 __flush_tlb_one((vaddr)); \
325 } while (0)
326
327 #endif
328