Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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#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
125static 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 */
134static 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
140static inline int pte_exec(pte_t pte){
141 return((pte_get_bits(pte, _PAGE_USER)) &&
142 !(pte_get_bits(pte, _PAGE_PROTNONE)));
143}
144
145static 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
151static inline int pte_dirty(pte_t pte)
152{
153 return pte_get_bits(pte, _PAGE_DIRTY);
154}
155
156static inline int pte_young(pte_t pte)
157{
158 return pte_get_bits(pte, _PAGE_ACCESSED);
159}
160
161static inline int pte_newpage(pte_t pte)
162{
163 return pte_get_bits(pte, _PAGE_NEWPAGE);
164}
165
166static 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
177static inline pte_t pte_mknewprot(pte_t pte)
178{
179 pte_set_bits(pte, _PAGE_NEWPROT);
180 return(pte);
181}
182
183static inline pte_t pte_mkclean(pte_t pte)
184{
185 pte_clear_bits(pte, _PAGE_DIRTY);
186 return(pte);
187}
188
189static inline pte_t pte_mkold(pte_t pte)
190{
191 pte_clear_bits(pte, _PAGE_ACCESSED);
192 return(pte);
193}
194
195static 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
204static 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
212static inline pte_t pte_mkdirty(pte_t pte)
213{
214 pte_set_bits(pte, _PAGE_DIRTY);
215 return(pte);
216}
217
218static inline pte_t pte_mkyoung(pte_t pte)
219{
220 pte_set_bits(pte, _PAGE_ACCESSED);
221 return(pte);
222}
223
224static 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
232static 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
240static inline pte_t pte_mknewpage(pte_t pte)
241{
242 pte_set_bits(pte, _PAGE_NEWPAGE);
243 return(pte);
244}
245
246static 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
259static 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
266static 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
289static 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
303struct mm_struct;
304extern 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) \
322do { \
323 pte_clear(&init_mm, (vaddr), (ptep)); \
324 __flush_tlb_one((vaddr)); \
325} while (0)
326
327#endif