xref: /openbmc/linux/arch/um/include/asm/pgtable.h (revision b627b4ed)
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 
31 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
32 
33 /* zero page used for uninitialized stuff */
34 extern 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 
46 extern 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 
57 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
58 #define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
59 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
60 
61 #define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
62 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
63 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
64 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
65 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
66 
67 /*
68  * The i386 can't do page protection for execute, and considers that the same
69  * are read.
70  * Also, write permissions imply read permissions. This is the closest we can
71  * get..
72  */
73 #define __P000	PAGE_NONE
74 #define __P001	PAGE_READONLY
75 #define __P010	PAGE_COPY
76 #define __P011	PAGE_COPY
77 #define __P100	PAGE_READONLY
78 #define __P101	PAGE_READONLY
79 #define __P110	PAGE_COPY
80 #define __P111	PAGE_COPY
81 
82 #define __S000	PAGE_NONE
83 #define __S001	PAGE_READONLY
84 #define __S010	PAGE_SHARED
85 #define __S011	PAGE_SHARED
86 #define __S100	PAGE_READONLY
87 #define __S101	PAGE_READONLY
88 #define __S110	PAGE_SHARED
89 #define __S111	PAGE_SHARED
90 
91 /*
92  * ZERO_PAGE is a global shared page that is always zero: used
93  * for zero-mapped memory areas etc..
94  */
95 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
96 
97 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
98 
99 #define pmd_none(x)	(!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
100 #define	pmd_bad(x)	((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
101 
102 #define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
103 #define pmd_clear(xp)	do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
104 
105 #define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
106 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
107 
108 #define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
109 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
110 
111 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
112 
113 #define pte_page(x) pfn_to_page(pte_pfn(x))
114 
115 #define pte_present(x)	pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
116 
117 /*
118  * =================================
119  * Flags checking section.
120  * =================================
121  */
122 
123 static inline int pte_none(pte_t pte)
124 {
125 	return pte_is_zero(pte);
126 }
127 
128 /*
129  * The following only work if pte_present() is true.
130  * Undefined behaviour if not..
131  */
132 static inline int pte_read(pte_t pte)
133 {
134 	return((pte_get_bits(pte, _PAGE_USER)) &&
135 	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
136 }
137 
138 static inline int pte_exec(pte_t pte){
139 	return((pte_get_bits(pte, _PAGE_USER)) &&
140 	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
141 }
142 
143 static inline int pte_write(pte_t pte)
144 {
145 	return((pte_get_bits(pte, _PAGE_RW)) &&
146 	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
147 }
148 
149 /*
150  * The following only works if pte_present() is not true.
151  */
152 static inline int pte_file(pte_t pte)
153 {
154 	return pte_get_bits(pte, _PAGE_FILE);
155 }
156 
157 static inline int pte_dirty(pte_t pte)
158 {
159 	return pte_get_bits(pte, _PAGE_DIRTY);
160 }
161 
162 static inline int pte_young(pte_t pte)
163 {
164 	return pte_get_bits(pte, _PAGE_ACCESSED);
165 }
166 
167 static inline int pte_newpage(pte_t pte)
168 {
169 	return pte_get_bits(pte, _PAGE_NEWPAGE);
170 }
171 
172 static inline int pte_newprot(pte_t pte)
173 {
174 	return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
175 }
176 
177 static inline int pte_special(pte_t pte)
178 {
179 	return 0;
180 }
181 
182 /*
183  * =================================
184  * Flags setting section.
185  * =================================
186  */
187 
188 static inline pte_t pte_mknewprot(pte_t pte)
189 {
190 	pte_set_bits(pte, _PAGE_NEWPROT);
191 	return(pte);
192 }
193 
194 static inline pte_t pte_mkclean(pte_t pte)
195 {
196 	pte_clear_bits(pte, _PAGE_DIRTY);
197 	return(pte);
198 }
199 
200 static inline pte_t pte_mkold(pte_t pte)
201 {
202 	pte_clear_bits(pte, _PAGE_ACCESSED);
203 	return(pte);
204 }
205 
206 static inline pte_t pte_wrprotect(pte_t pte)
207 {
208 	pte_clear_bits(pte, _PAGE_RW);
209 	return(pte_mknewprot(pte));
210 }
211 
212 static inline pte_t pte_mkread(pte_t pte)
213 {
214 	pte_set_bits(pte, _PAGE_USER);
215 	return(pte_mknewprot(pte));
216 }
217 
218 static inline pte_t pte_mkdirty(pte_t pte)
219 {
220 	pte_set_bits(pte, _PAGE_DIRTY);
221 	return(pte);
222 }
223 
224 static inline pte_t pte_mkyoung(pte_t pte)
225 {
226 	pte_set_bits(pte, _PAGE_ACCESSED);
227 	return(pte);
228 }
229 
230 static inline pte_t pte_mkwrite(pte_t pte)
231 {
232 	pte_set_bits(pte, _PAGE_RW);
233 	return(pte_mknewprot(pte));
234 }
235 
236 static inline pte_t pte_mkuptodate(pte_t pte)
237 {
238 	pte_clear_bits(pte, _PAGE_NEWPAGE);
239 	if(pte_present(pte))
240 		pte_clear_bits(pte, _PAGE_NEWPROT);
241 	return(pte);
242 }
243 
244 static inline pte_t pte_mknewpage(pte_t pte)
245 {
246 	pte_set_bits(pte, _PAGE_NEWPAGE);
247 	return(pte);
248 }
249 
250 static inline pte_t pte_mkspecial(pte_t pte)
251 {
252 	return(pte);
253 }
254 
255 static inline void set_pte(pte_t *pteptr, pte_t pteval)
256 {
257 	pte_copy(*pteptr, pteval);
258 
259 	/* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
260 	 * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
261 	 * mapped pages.
262 	 */
263 
264 	*pteptr = pte_mknewpage(*pteptr);
265 	if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
266 }
267 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
268 
269 /*
270  * Conversion functions: convert a page and protection to a page entry,
271  * and a page entry and page directory to the page they refer to.
272  */
273 
274 #define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
275 #define __virt_to_page(virt) phys_to_page(__pa(virt))
276 #define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
277 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
278 
279 #define mk_pte(page, pgprot) \
280 	({ pte_t pte;					\
281 							\
282 	pte_set_val(pte, page_to_phys(page), (pgprot));	\
283 	if (pte_present(pte))				\
284 		pte_mknewprot(pte_mknewpage(pte));	\
285 	pte;})
286 
287 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
288 {
289 	pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
290 	return pte;
291 }
292 
293 /*
294  * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
295  *
296  * this macro returns the index of the entry in the pgd page which would
297  * control the given virtual address
298  */
299 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
300 
301 /*
302  * pgd_offset() returns a (pgd_t *)
303  * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
304  */
305 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
306 
307 /*
308  * a shortcut which implies the use of the kernel's pgd, instead
309  * of a process's
310  */
311 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
312 
313 /*
314  * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
315  *
316  * this macro returns the index of the entry in the pmd page which would
317  * control the given virtual address
318  */
319 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
320 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
321 
322 #define pmd_page_vaddr(pmd) \
323 	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
324 
325 /*
326  * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
327  *
328  * this macro returns the index of the entry in the pte page which would
329  * control the given virtual address
330  */
331 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
332 #define pte_offset_kernel(dir, address) \
333 	((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
334 #define pte_offset_map(dir, address) \
335 	((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
336 #define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
337 #define pte_unmap(pte) do { } while (0)
338 #define pte_unmap_nested(pte) do { } while (0)
339 
340 struct mm_struct;
341 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
342 
343 #define update_mmu_cache(vma,address,pte) do ; while (0)
344 
345 /* Encode and de-code a swap entry */
346 #define __swp_type(x)			(((x).val >> 4) & 0x3f)
347 #define __swp_offset(x)			((x).val >> 11)
348 
349 #define __swp_entry(type, offset) \
350 	((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
351 #define __pte_to_swp_entry(pte) \
352 	((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
353 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
354 
355 #define kern_addr_valid(addr) (1)
356 
357 #include <asm-generic/pgtable.h>
358 
359 /* Clear a kernel PTE and flush it from the TLB */
360 #define kpte_clear_flush(ptep, vaddr)		\
361 do {						\
362 	pte_clear(&init_mm, (vaddr), (ptep));	\
363 	__flush_tlb_one((vaddr));		\
364 } while (0)
365 
366 #endif
367