Linux kernel mirror (for testing)
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1/*
2 * arch/arm/include/asm/pgtable.h
3 *
4 * Copyright (C) 1995-2002 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#ifndef _ASMARM_PGTABLE_H
11#define _ASMARM_PGTABLE_H
12
13#include <linux/const.h>
14#include <asm/proc-fns.h>
15
16#ifndef CONFIG_MMU
17
18#include <asm-generic/4level-fixup.h>
19#include <asm/pgtable-nommu.h>
20
21#else
22
23#include <asm-generic/pgtable-nopud.h>
24#include <asm/memory.h>
25#include <asm/pgtable-hwdef.h>
26
27#ifdef CONFIG_ARM_LPAE
28#include <asm/pgtable-3level.h>
29#else
30#include <asm/pgtable-2level.h>
31#endif
32
33/*
34 * Just any arbitrary offset to the start of the vmalloc VM area: the
35 * current 8MB value just means that there will be a 8MB "hole" after the
36 * physical memory until the kernel virtual memory starts. That means that
37 * any out-of-bounds memory accesses will hopefully be caught.
38 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
39 * area for the same reason. ;)
40 */
41#define VMALLOC_OFFSET (8*1024*1024)
42#define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
43#define VMALLOC_END 0xff000000UL
44
45#define LIBRARY_TEXT_START 0x0c000000
46
47#ifndef __ASSEMBLY__
48extern void __pte_error(const char *file, int line, pte_t);
49extern void __pmd_error(const char *file, int line, pmd_t);
50extern void __pgd_error(const char *file, int line, pgd_t);
51
52#define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte)
53#define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd)
54#define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd)
55
56/*
57 * This is the lowest virtual address we can permit any user space
58 * mapping to be mapped at. This is particularly important for
59 * non-high vector CPUs.
60 */
61#define FIRST_USER_ADDRESS PAGE_SIZE
62
63/*
64 * The pgprot_* and protection_map entries will be fixed up in runtime
65 * to include the cachable and bufferable bits based on memory policy,
66 * as well as any architecture dependent bits like global/ASID and SMP
67 * shared mapping bits.
68 */
69#define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG
70
71extern pgprot_t pgprot_user;
72extern pgprot_t pgprot_kernel;
73extern pgprot_t pgprot_hyp_device;
74extern pgprot_t pgprot_s2;
75extern pgprot_t pgprot_s2_device;
76
77#define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
78
79#define PAGE_NONE _MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY | L_PTE_NONE)
80#define PAGE_SHARED _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
81#define PAGE_SHARED_EXEC _MOD_PROT(pgprot_user, L_PTE_USER)
82#define PAGE_COPY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
83#define PAGE_COPY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
84#define PAGE_READONLY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
85#define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
86#define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
87#define PAGE_KERNEL_EXEC pgprot_kernel
88#define PAGE_HYP _MOD_PROT(pgprot_kernel, L_PTE_HYP)
89#define PAGE_HYP_DEVICE _MOD_PROT(pgprot_hyp_device, L_PTE_HYP)
90#define PAGE_S2 _MOD_PROT(pgprot_s2, L_PTE_S2_RDONLY)
91#define PAGE_S2_DEVICE _MOD_PROT(pgprot_s2_device, L_PTE_USER | L_PTE_S2_RDONLY)
92
93#define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN | L_PTE_NONE)
94#define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
95#define __PAGE_SHARED_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER)
96#define __PAGE_COPY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
97#define __PAGE_COPY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
98#define __PAGE_READONLY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
99#define __PAGE_READONLY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
100
101#define __pgprot_modify(prot,mask,bits) \
102 __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
103
104#define pgprot_noncached(prot) \
105 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
106
107#define pgprot_writecombine(prot) \
108 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
109
110#define pgprot_stronglyordered(prot) \
111 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
112
113#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
114#define pgprot_dmacoherent(prot) \
115 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
116#define __HAVE_PHYS_MEM_ACCESS_PROT
117struct file;
118extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
119 unsigned long size, pgprot_t vma_prot);
120#else
121#define pgprot_dmacoherent(prot) \
122 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
123#endif
124
125#endif /* __ASSEMBLY__ */
126
127/*
128 * The table below defines the page protection levels that we insert into our
129 * Linux page table version. These get translated into the best that the
130 * architecture can perform. Note that on most ARM hardware:
131 * 1) We cannot do execute protection
132 * 2) If we could do execute protection, then read is implied
133 * 3) write implies read permissions
134 */
135#define __P000 __PAGE_NONE
136#define __P001 __PAGE_READONLY
137#define __P010 __PAGE_COPY
138#define __P011 __PAGE_COPY
139#define __P100 __PAGE_READONLY_EXEC
140#define __P101 __PAGE_READONLY_EXEC
141#define __P110 __PAGE_COPY_EXEC
142#define __P111 __PAGE_COPY_EXEC
143
144#define __S000 __PAGE_NONE
145#define __S001 __PAGE_READONLY
146#define __S010 __PAGE_SHARED
147#define __S011 __PAGE_SHARED
148#define __S100 __PAGE_READONLY_EXEC
149#define __S101 __PAGE_READONLY_EXEC
150#define __S110 __PAGE_SHARED_EXEC
151#define __S111 __PAGE_SHARED_EXEC
152
153#ifndef __ASSEMBLY__
154/*
155 * ZERO_PAGE is a global shared page that is always zero: used
156 * for zero-mapped memory areas etc..
157 */
158extern struct page *empty_zero_page;
159#define ZERO_PAGE(vaddr) (empty_zero_page)
160
161
162extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
163
164/* to find an entry in a page-table-directory */
165#define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
166
167#define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
168
169/* to find an entry in a kernel page-table-directory */
170#define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
171
172#define pmd_none(pmd) (!pmd_val(pmd))
173#define pmd_present(pmd) (pmd_val(pmd))
174
175static inline pte_t *pmd_page_vaddr(pmd_t pmd)
176{
177 return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
178}
179
180#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
181
182#ifndef CONFIG_HIGHPTE
183#define __pte_map(pmd) pmd_page_vaddr(*(pmd))
184#define __pte_unmap(pte) do { } while (0)
185#else
186#define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd)))
187#define __pte_unmap(pte) kunmap_atomic(pte)
188#endif
189
190#define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
191
192#define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr))
193
194#define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr))
195#define pte_unmap(pte) __pte_unmap(pte)
196
197#define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
198#define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
199
200#define pte_page(pte) pfn_to_page(pte_pfn(pte))
201#define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot)
202
203#define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0)
204
205#define pte_none(pte) (!pte_val(pte))
206#define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT)
207#define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY))
208#define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY)
209#define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG)
210#define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN))
211#define pte_special(pte) (0)
212
213#define pte_present_user(pte) (pte_present(pte) && (pte_val(pte) & L_PTE_USER))
214
215#if __LINUX_ARM_ARCH__ < 6
216static inline void __sync_icache_dcache(pte_t pteval)
217{
218}
219#else
220extern void __sync_icache_dcache(pte_t pteval);
221#endif
222
223static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
224 pte_t *ptep, pte_t pteval)
225{
226 unsigned long ext = 0;
227
228 if (addr < TASK_SIZE && pte_present_user(pteval)) {
229 __sync_icache_dcache(pteval);
230 ext |= PTE_EXT_NG;
231 }
232
233 set_pte_ext(ptep, pteval, ext);
234}
235
236#define PTE_BIT_FUNC(fn,op) \
237static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
238
239PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY);
240PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY);
241PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY);
242PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY);
243PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG);
244PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG);
245
246static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
247
248static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
249{
250 const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER |
251 L_PTE_NONE | L_PTE_VALID;
252 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
253 return pte;
254}
255
256/*
257 * Encode and decode a swap entry. Swap entries are stored in the Linux
258 * page tables as follows:
259 *
260 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
261 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
262 * <--------------- offset ----------------------> < type -> 0 0 0
263 *
264 * This gives us up to 31 swap files and 64GB per swap file. Note that
265 * the offset field is always non-zero.
266 */
267#define __SWP_TYPE_SHIFT 3
268#define __SWP_TYPE_BITS 5
269#define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
270#define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
271
272#define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
273#define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
274#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
275
276#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
277#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
278
279/*
280 * It is an error for the kernel to have more swap files than we can
281 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES
282 * is increased beyond what we presently support.
283 */
284#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
285
286/*
287 * Encode and decode a file entry. File entries are stored in the Linux
288 * page tables as follows:
289 *
290 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
291 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
292 * <----------------------- offset ------------------------> 1 0 0
293 */
294#define pte_file(pte) (pte_val(pte) & L_PTE_FILE)
295#define pte_to_pgoff(x) (pte_val(x) >> 3)
296#define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE)
297
298#define PTE_FILE_MAX_BITS 29
299
300/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
301/* FIXME: this is not correct */
302#define kern_addr_valid(addr) (1)
303
304#include <asm-generic/pgtable.h>
305
306/*
307 * We provide our own arch_get_unmapped_area to cope with VIPT caches.
308 */
309#define HAVE_ARCH_UNMAPPED_AREA
310#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
311
312/*
313 * remap a physical page `pfn' of size `size' with page protection `prot'
314 * into virtual address `from'
315 */
316#define io_remap_pfn_range(vma,from,pfn,size,prot) \
317 remap_pfn_range(vma, from, pfn, size, prot)
318
319#define pgtable_cache_init() do { } while (0)
320
321#endif /* !__ASSEMBLY__ */
322
323#endif /* CONFIG_MMU */
324
325#endif /* _ASMARM_PGTABLE_H */