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
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
pte_none(pte_t pte)108 static 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 */
pte_read(pte_t pte)117 static 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
pte_exec(pte_t pte)123 static inline int pte_exec(pte_t pte){
124 return((pte_get_bits(pte, _PAGE_USER)) &&
125 !(pte_get_bits(pte, _PAGE_PROTNONE)));
126 }
127
pte_write(pte_t pte)128 static 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
pte_dirty(pte_t pte)134 static inline int pte_dirty(pte_t pte)
135 {
136 return pte_get_bits(pte, _PAGE_DIRTY);
137 }
138
pte_young(pte_t pte)139 static inline int pte_young(pte_t pte)
140 {
141 return pte_get_bits(pte, _PAGE_ACCESSED);
142 }
143
pte_newpage(pte_t pte)144 static inline int pte_newpage(pte_t pte)
145 {
146 return pte_get_bits(pte, _PAGE_NEWPAGE);
147 }
148
pte_newprot(pte_t pte)149 static 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
pte_mknewprot(pte_t pte)160 static inline pte_t pte_mknewprot(pte_t pte)
161 {
162 pte_set_bits(pte, _PAGE_NEWPROT);
163 return(pte);
164 }
165
pte_mkclean(pte_t pte)166 static inline pte_t pte_mkclean(pte_t pte)
167 {
168 pte_clear_bits(pte, _PAGE_DIRTY);
169 return(pte);
170 }
171
pte_mkold(pte_t pte)172 static inline pte_t pte_mkold(pte_t pte)
173 {
174 pte_clear_bits(pte, _PAGE_ACCESSED);
175 return(pte);
176 }
177
pte_wrprotect(pte_t pte)178 static 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
pte_mkread(pte_t pte)187 static 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
pte_mkdirty(pte_t pte)195 static inline pte_t pte_mkdirty(pte_t pte)
196 {
197 pte_set_bits(pte, _PAGE_DIRTY);
198 return(pte);
199 }
200
pte_mkyoung(pte_t pte)201 static inline pte_t pte_mkyoung(pte_t pte)
202 {
203 pte_set_bits(pte, _PAGE_ACCESSED);
204 return(pte);
205 }
206
pte_mkwrite(pte_t pte)207 static 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
pte_mkuptodate(pte_t pte)215 static 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
pte_mknewpage(pte_t pte)223 static inline pte_t pte_mknewpage(pte_t pte)
224 {
225 pte_set_bits(pte, _PAGE_NEWPAGE);
226 return(pte);
227 }
228
set_pte(pte_t * pteptr,pte_t pteval)229 static 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
set_pte_at(struct mm_struct * mm,unsigned long addr,pte_t * pteptr,pte_t pteval)242 static 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
pte_same(pte_t pte_a,pte_t pte_b)249 static 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
pte_modify(pte_t pte,pgprot_t newprot)272 static 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
286 struct mm_struct;
287 extern 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 #define kern_addr_valid(addr) (1)
302
303 /* Clear a kernel PTE and flush it from the TLB */
304 #define kpte_clear_flush(ptep, vaddr) \
305 do { \
306 pte_clear(&init_mm, (vaddr), (ptep)); \
307 __flush_tlb_one((vaddr)); \
308 } while (0)
309
310 #endif
311
