xref: /openbmc/linux/arch/um/include/asm/pgtable.h (revision 8b036556)
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_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 #define pgtable_cache_init() do ; while (0)
36 
37 /* Just any arbitrary offset to the start of the vmalloc VM area: the
38  * current 8MB value just means that there will be a 8MB "hole" after the
39  * physical memory until the kernel virtual memory starts.  That means that
40  * any out-of-bounds memory accesses will hopefully be caught.
41  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
42  * area for the same reason. ;)
43  */
44 
45 extern unsigned long end_iomem;
46 
47 #define VMALLOC_OFFSET	(__va_space)
48 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
49 #define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
50 #ifdef CONFIG_HIGHMEM
51 # define VMALLOC_END	(PKMAP_BASE-2*PAGE_SIZE)
52 #else
53 # define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
54 #endif
55 #define MODULES_VADDR	VMALLOC_START
56 #define MODULES_END	VMALLOC_END
57 #define MODULES_LEN	(MODULES_VADDR - MODULES_END)
58 
59 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
60 #define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
61 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
62 #define __PAGE_KERNEL_EXEC                                              \
63 	 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
64 #define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
65 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
66 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
67 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
68 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
69 #define PAGE_KERNEL_EXEC	__pgprot(__PAGE_KERNEL_EXEC)
70 
71 /*
72  * The i386 can't do page protection for execute, and considers that the same
73  * are read.
74  * Also, write permissions imply read permissions. This is the closest we can
75  * get..
76  */
77 #define __P000	PAGE_NONE
78 #define __P001	PAGE_READONLY
79 #define __P010	PAGE_COPY
80 #define __P011	PAGE_COPY
81 #define __P100	PAGE_READONLY
82 #define __P101	PAGE_READONLY
83 #define __P110	PAGE_COPY
84 #define __P111	PAGE_COPY
85 
86 #define __S000	PAGE_NONE
87 #define __S001	PAGE_READONLY
88 #define __S010	PAGE_SHARED
89 #define __S011	PAGE_SHARED
90 #define __S100	PAGE_READONLY
91 #define __S101	PAGE_READONLY
92 #define __S110	PAGE_SHARED
93 #define __S111	PAGE_SHARED
94 
95 /*
96  * ZERO_PAGE is a global shared page that is always zero: used
97  * for zero-mapped memory areas etc..
98  */
99 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
100 
101 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
102 
103 #define pmd_none(x)	(!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
104 #define	pmd_bad(x)	((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
105 
106 #define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
107 #define pmd_clear(xp)	do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
108 
109 #define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
110 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
111 
112 #define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
113 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
114 
115 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
116 
117 #define pte_page(x) pfn_to_page(pte_pfn(x))
118 
119 #define pte_present(x)	pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
120 
121 /*
122  * =================================
123  * Flags checking section.
124  * =================================
125  */
126 
127 static inline int pte_none(pte_t pte)
128 {
129 	return pte_is_zero(pte);
130 }
131 
132 /*
133  * The following only work if pte_present() is true.
134  * Undefined behaviour if not..
135  */
136 static inline int pte_read(pte_t pte)
137 {
138 	return((pte_get_bits(pte, _PAGE_USER)) &&
139 	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
140 }
141 
142 static inline int pte_exec(pte_t pte){
143 	return((pte_get_bits(pte, _PAGE_USER)) &&
144 	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
145 }
146 
147 static inline int pte_write(pte_t pte)
148 {
149 	return((pte_get_bits(pte, _PAGE_RW)) &&
150 	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
151 }
152 
153 static inline int pte_dirty(pte_t pte)
154 {
155 	return pte_get_bits(pte, _PAGE_DIRTY);
156 }
157 
158 static inline int pte_young(pte_t pte)
159 {
160 	return pte_get_bits(pte, _PAGE_ACCESSED);
161 }
162 
163 static inline int pte_newpage(pte_t pte)
164 {
165 	return pte_get_bits(pte, _PAGE_NEWPAGE);
166 }
167 
168 static inline int pte_newprot(pte_t pte)
169 {
170 	return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
171 }
172 
173 static inline int pte_special(pte_t pte)
174 {
175 	return 0;
176 }
177 
178 /*
179  * =================================
180  * Flags setting section.
181  * =================================
182  */
183 
184 static inline pte_t pte_mknewprot(pte_t pte)
185 {
186 	pte_set_bits(pte, _PAGE_NEWPROT);
187 	return(pte);
188 }
189 
190 static inline pte_t pte_mkclean(pte_t pte)
191 {
192 	pte_clear_bits(pte, _PAGE_DIRTY);
193 	return(pte);
194 }
195 
196 static inline pte_t pte_mkold(pte_t pte)
197 {
198 	pte_clear_bits(pte, _PAGE_ACCESSED);
199 	return(pte);
200 }
201 
202 static inline pte_t pte_wrprotect(pte_t pte)
203 {
204 	pte_clear_bits(pte, _PAGE_RW);
205 	return(pte_mknewprot(pte));
206 }
207 
208 static inline pte_t pte_mkread(pte_t pte)
209 {
210 	pte_set_bits(pte, _PAGE_USER);
211 	return(pte_mknewprot(pte));
212 }
213 
214 static inline pte_t pte_mkdirty(pte_t pte)
215 {
216 	pte_set_bits(pte, _PAGE_DIRTY);
217 	return(pte);
218 }
219 
220 static inline pte_t pte_mkyoung(pte_t pte)
221 {
222 	pte_set_bits(pte, _PAGE_ACCESSED);
223 	return(pte);
224 }
225 
226 static inline pte_t pte_mkwrite(pte_t pte)
227 {
228 	pte_set_bits(pte, _PAGE_RW);
229 	return(pte_mknewprot(pte));
230 }
231 
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 
240 static inline pte_t pte_mknewpage(pte_t pte)
241 {
242 	pte_set_bits(pte, _PAGE_NEWPAGE);
243 	return(pte);
244 }
245 
246 static inline pte_t pte_mkspecial(pte_t pte)
247 {
248 	return(pte);
249 }
250 
251 static inline void set_pte(pte_t *pteptr, pte_t pteval)
252 {
253 	pte_copy(*pteptr, pteval);
254 
255 	/* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
256 	 * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
257 	 * mapped pages.
258 	 */
259 
260 	*pteptr = pte_mknewpage(*pteptr);
261 	if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
262 }
263 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
264 
265 #define __HAVE_ARCH_PTE_SAME
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((pfn_t) 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 
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 pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
297  *
298  * this macro returns the index of the entry in the pgd page which would
299  * control the given virtual address
300  */
301 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
302 
303 /*
304  * pgd_offset() returns a (pgd_t *)
305  * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
306  */
307 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
308 
309 /*
310  * a shortcut which implies the use of the kernel's pgd, instead
311  * of a process's
312  */
313 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
314 
315 /*
316  * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
317  *
318  * this macro returns the index of the entry in the pmd page which would
319  * control the given virtual address
320  */
321 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
322 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
323 
324 #define pmd_page_vaddr(pmd) \
325 	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
326 
327 /*
328  * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
329  *
330  * this macro returns the index of the entry in the pte page which would
331  * control the given virtual address
332  */
333 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
334 #define pte_offset_kernel(dir, address) \
335 	((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
336 #define pte_offset_map(dir, address) \
337 	((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
338 #define pte_unmap(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,ptep) do ; while (0)
344 
345 /* Encode and de-code a swap entry */
346 #define __swp_type(x)			(((x).val >> 5) & 0x1f)
347 #define __swp_offset(x)			((x).val >> 11)
348 
349 #define __swp_entry(type, offset) \
350 	((swp_entry_t) { ((type) << 5) | ((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