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
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#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
45extern 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#define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
51#define MODULES_VADDR	VMALLOC_START
52#define MODULES_END	VMALLOC_END
53#define MODULES_LEN	(MODULES_VADDR - MODULES_END)
54
55#define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
56#define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
57#define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
58#define __PAGE_KERNEL_EXEC                                              \
59	 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
60#define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
61#define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
62#define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
63#define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
64#define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
65#define PAGE_KERNEL_EXEC	__pgprot(__PAGE_KERNEL_EXEC)
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
123static 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 */
132static 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
138static inline int pte_exec(pte_t pte){
139	return((pte_get_bits(pte, _PAGE_USER)) &&
140	       !(pte_get_bits(pte, _PAGE_PROTNONE)));
141}
142
143static 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
149static inline int pte_dirty(pte_t pte)
150{
151	return pte_get_bits(pte, _PAGE_DIRTY);
152}
153
154static inline int pte_young(pte_t pte)
155{
156	return pte_get_bits(pte, _PAGE_ACCESSED);
157}
158
159static inline int pte_newpage(pte_t pte)
160{
161	return pte_get_bits(pte, _PAGE_NEWPAGE);
162}
163
164static inline int pte_newprot(pte_t pte)
165{
166	return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
167}
168
169static inline int pte_special(pte_t pte)
170{
171	return 0;
172}
173
174/*
175 * =================================
176 * Flags setting section.
177 * =================================
178 */
179
180static inline pte_t pte_mknewprot(pte_t pte)
181{
182	pte_set_bits(pte, _PAGE_NEWPROT);
183	return(pte);
184}
185
186static inline pte_t pte_mkclean(pte_t pte)
187{
188	pte_clear_bits(pte, _PAGE_DIRTY);
189	return(pte);
190}
191
192static inline pte_t pte_mkold(pte_t pte)
193{
194	pte_clear_bits(pte, _PAGE_ACCESSED);
195	return(pte);
196}
197
198static inline pte_t pte_wrprotect(pte_t pte)
199{
200	pte_clear_bits(pte, _PAGE_RW);
201	return(pte_mknewprot(pte));
202}
203
204static inline pte_t pte_mkread(pte_t pte)
205{
206	pte_set_bits(pte, _PAGE_USER);
207	return(pte_mknewprot(pte));
208}
209
210static inline pte_t pte_mkdirty(pte_t pte)
211{
212	pte_set_bits(pte, _PAGE_DIRTY);
213	return(pte);
214}
215
216static inline pte_t pte_mkyoung(pte_t pte)
217{
218	pte_set_bits(pte, _PAGE_ACCESSED);
219	return(pte);
220}
221
222static inline pte_t pte_mkwrite(pte_t pte)
223{
224	pte_set_bits(pte, _PAGE_RW);
225	return(pte_mknewprot(pte));
226}
227
228static inline pte_t pte_mkuptodate(pte_t pte)
229{
230	pte_clear_bits(pte, _PAGE_NEWPAGE);
231	if(pte_present(pte))
232		pte_clear_bits(pte, _PAGE_NEWPROT);
233	return(pte);
234}
235
236static inline pte_t pte_mknewpage(pte_t pte)
237{
238	pte_set_bits(pte, _PAGE_NEWPAGE);
239	return(pte);
240}
241
242static inline pte_t pte_mkspecial(pte_t pte)
243{
244	return(pte);
245}
246
247static inline void set_pte(pte_t *pteptr, pte_t pteval)
248{
249	pte_copy(*pteptr, pteval);
250
251	/* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
252	 * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
253	 * mapped pages.
254	 */
255
256	*pteptr = pte_mknewpage(*pteptr);
257	if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
258}
259#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
260
261#define __HAVE_ARCH_PTE_SAME
262static inline int pte_same(pte_t pte_a, pte_t pte_b)
263{
264	return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
265}
266
267/*
268 * Conversion functions: convert a page and protection to a page entry,
269 * and a page entry and page directory to the page they refer to.
270 */
271
272#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
273#define __virt_to_page(virt) phys_to_page(__pa(virt))
274#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
275#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
276
277#define mk_pte(page, pgprot) \
278	({ pte_t pte;					\
279							\
280	pte_set_val(pte, page_to_phys(page), (pgprot));	\
281	if (pte_present(pte))				\
282		pte_mknewprot(pte_mknewpage(pte));	\
283	pte;})
284
285static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
286{
287	pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
288	return pte;
289}
290
291/*
292 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
293 *
294 * this macro returns the index of the entry in the pgd page which would
295 * control the given virtual address
296 */
297#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
298
299/*
300 * pgd_offset() returns a (pgd_t *)
301 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
302 */
303#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
304
305/*
306 * a shortcut which implies the use of the kernel's pgd, instead
307 * of a process's
308 */
309#define pgd_offset_k(address) pgd_offset(&init_mm, address)
310
311/*
312 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
313 *
314 * this macro returns the index of the entry in the pmd page which would
315 * control the given virtual address
316 */
317#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
318#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
319
320#define pmd_page_vaddr(pmd) \
321	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
322
323/*
324 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
325 *
326 * this macro returns the index of the entry in the pte page which would
327 * control the given virtual address
328 */
329#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
330#define pte_offset_kernel(dir, address) \
331	((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
332#define pte_offset_map(dir, address) \
333	((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
334#define pte_unmap(pte) do { } while (0)
335
336struct mm_struct;
337extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
338
339#define update_mmu_cache(vma,address,ptep) do ; while (0)
340
341/* Encode and de-code a swap entry */
342#define __swp_type(x)			(((x).val >> 5) & 0x1f)
343#define __swp_offset(x)			((x).val >> 11)
344
345#define __swp_entry(type, offset) \
346	((swp_entry_t) { ((type) << 5) | ((offset) << 11) })
347#define __pte_to_swp_entry(pte) \
348	((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
349#define __swp_entry_to_pte(x)		((pte_t) { (x).val })
350
351#define kern_addr_valid(addr) (1)
352
353#include <asm-generic/pgtable.h>
354
355/* Clear a kernel PTE and flush it from the TLB */
356#define kpte_clear_flush(ptep, vaddr)		\
357do {						\
358	pte_clear(&init_mm, (vaddr), (ptep));	\
359	__flush_tlb_one((vaddr));		\
360} while (0)
361
362#endif
363