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