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v3.5.6
  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 "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;
 
 
 
 73
 74#define _MOD_PROT(p, b)	__pgprot(pgprot_val(p) | (b))
 75
 76#define PAGE_NONE		_MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY)
 77#define PAGE_SHARED		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
 78#define PAGE_SHARED_EXEC	_MOD_PROT(pgprot_user, L_PTE_USER)
 79#define PAGE_COPY		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
 80#define PAGE_COPY_EXEC		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
 81#define PAGE_READONLY		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
 82#define PAGE_READONLY_EXEC	_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
 83#define PAGE_KERNEL		_MOD_PROT(pgprot_kernel, L_PTE_XN)
 84#define PAGE_KERNEL_EXEC	pgprot_kernel
 
 
 
 
 
 
 85
 86#define __PAGE_NONE		__pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN)
 87#define __PAGE_SHARED		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
 88#define __PAGE_SHARED_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER)
 89#define __PAGE_COPY		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
 90#define __PAGE_COPY_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
 91#define __PAGE_READONLY		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
 92#define __PAGE_READONLY_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
 93
 94#define __pgprot_modify(prot,mask,bits)		\
 95	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
 96
 97#define pgprot_noncached(prot) \
 98	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
 99
100#define pgprot_writecombine(prot) \
101	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
102
103#define pgprot_stronglyordered(prot) \
104	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
105
106#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
107#define pgprot_dmacoherent(prot) \
108	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
109#define __HAVE_PHYS_MEM_ACCESS_PROT
110struct file;
111extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
112				     unsigned long size, pgprot_t vma_prot);
113#else
114#define pgprot_dmacoherent(prot) \
115	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
116#endif
117
118#endif /* __ASSEMBLY__ */
119
120/*
121 * The table below defines the page protection levels that we insert into our
122 * Linux page table version.  These get translated into the best that the
123 * architecture can perform.  Note that on most ARM hardware:
124 *  1) We cannot do execute protection
125 *  2) If we could do execute protection, then read is implied
126 *  3) write implies read permissions
127 */
128#define __P000  __PAGE_NONE
129#define __P001  __PAGE_READONLY
130#define __P010  __PAGE_COPY
131#define __P011  __PAGE_COPY
132#define __P100  __PAGE_READONLY_EXEC
133#define __P101  __PAGE_READONLY_EXEC
134#define __P110  __PAGE_COPY_EXEC
135#define __P111  __PAGE_COPY_EXEC
136
137#define __S000  __PAGE_NONE
138#define __S001  __PAGE_READONLY
139#define __S010  __PAGE_SHARED
140#define __S011  __PAGE_SHARED
141#define __S100  __PAGE_READONLY_EXEC
142#define __S101  __PAGE_READONLY_EXEC
143#define __S110  __PAGE_SHARED_EXEC
144#define __S111  __PAGE_SHARED_EXEC
145
146#ifndef __ASSEMBLY__
147/*
148 * ZERO_PAGE is a global shared page that is always zero: used
149 * for zero-mapped memory areas etc..
150 */
151extern struct page *empty_zero_page;
152#define ZERO_PAGE(vaddr)	(empty_zero_page)
153
154
155extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
156
157/* to find an entry in a page-table-directory */
158#define pgd_index(addr)		((addr) >> PGDIR_SHIFT)
159
160#define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
161
162/* to find an entry in a kernel page-table-directory */
163#define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
164
165#define pmd_none(pmd)		(!pmd_val(pmd))
166#define pmd_present(pmd)	(pmd_val(pmd))
167
168static inline pte_t *pmd_page_vaddr(pmd_t pmd)
169{
170	return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
171}
172
173#define pmd_page(pmd)		pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
174
175#ifndef CONFIG_HIGHPTE
176#define __pte_map(pmd)		pmd_page_vaddr(*(pmd))
177#define __pte_unmap(pte)	do { } while (0)
178#else
179#define __pte_map(pmd)		(pte_t *)kmap_atomic(pmd_page(*(pmd)))
180#define __pte_unmap(pte)	kunmap_atomic(pte)
181#endif
182
183#define pte_index(addr)		(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
184
185#define pte_offset_kernel(pmd,addr)	(pmd_page_vaddr(*(pmd)) + pte_index(addr))
186
187#define pte_offset_map(pmd,addr)	(__pte_map(pmd) + pte_index(addr))
188#define pte_unmap(pte)			__pte_unmap(pte)
189
190#define pte_pfn(pte)		((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
191#define pfn_pte(pfn,prot)	__pte(__pfn_to_phys(pfn) | pgprot_val(prot))
192
193#define pte_page(pte)		pfn_to_page(pte_pfn(pte))
194#define mk_pte(page,prot)	pfn_pte(page_to_pfn(page), prot)
195
196#define pte_clear(mm,addr,ptep)	set_pte_ext(ptep, __pte(0), 0)
197
 
 
 
 
198#define pte_none(pte)		(!pte_val(pte))
199#define pte_present(pte)	(pte_val(pte) & L_PTE_PRESENT)
200#define pte_write(pte)		(!(pte_val(pte) & L_PTE_RDONLY))
201#define pte_dirty(pte)		(pte_val(pte) & L_PTE_DIRTY)
202#define pte_young(pte)		(pte_val(pte) & L_PTE_YOUNG)
203#define pte_exec(pte)		(!(pte_val(pte) & L_PTE_XN))
204#define pte_special(pte)	(0)
205
206#define pte_present_user(pte) \
207	((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \
208	 (L_PTE_PRESENT | L_PTE_USER))
 
 
 
 
 
 
 
 
 
 
 
 
209
210#if __LINUX_ARM_ARCH__ < 6
211static inline void __sync_icache_dcache(pte_t pteval)
212{
213}
214#else
215extern void __sync_icache_dcache(pte_t pteval);
216#endif
217
218static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
219			      pte_t *ptep, pte_t pteval)
220{
221	unsigned long ext = 0;
222
223	if (addr < TASK_SIZE && pte_present_user(pteval)) {
224		__sync_icache_dcache(pteval);
 
225		ext |= PTE_EXT_NG;
226	}
227
228	set_pte_ext(ptep, pteval, ext);
229}
230
231#define PTE_BIT_FUNC(fn,op) \
232static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
233
234PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY);
235PTE_BIT_FUNC(mkwrite,   &= ~L_PTE_RDONLY);
236PTE_BIT_FUNC(mkclean,   &= ~L_PTE_DIRTY);
237PTE_BIT_FUNC(mkdirty,   |= L_PTE_DIRTY);
238PTE_BIT_FUNC(mkold,     &= ~L_PTE_YOUNG);
239PTE_BIT_FUNC(mkyoung,   |= L_PTE_YOUNG);
240
241static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
 
 
 
 
 
 
 
 
242
243static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
244{
245	const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER;
 
246	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
247	return pte;
248}
249
250/*
251 * Encode and decode a swap entry.  Swap entries are stored in the Linux
252 * page tables as follows:
253 *
254 *   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
255 *   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
256 *   <--------------- offset ----------------------> < type -> 0 0 0
257 *
258 * This gives us up to 31 swap files and 64GB per swap file.  Note that
259 * the offset field is always non-zero.
260 */
261#define __SWP_TYPE_SHIFT	3
262#define __SWP_TYPE_BITS		5
263#define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
264#define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
265
266#define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
267#define __swp_offset(x)		((x).val >> __SWP_OFFSET_SHIFT)
268#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
269
270#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
271#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
272
273/*
274 * It is an error for the kernel to have more swap files than we can
275 * encode in the PTEs.  This ensures that we know when MAX_SWAPFILES
276 * is increased beyond what we presently support.
277 */
278#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
279
280/*
281 * Encode and decode a file entry.  File entries are stored in the Linux
282 * page tables as follows:
283 *
284 *   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
285 *   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
286 *   <----------------------- offset ------------------------> 1 0 0
287 */
288#define pte_file(pte)		(pte_val(pte) & L_PTE_FILE)
289#define pte_to_pgoff(x)		(pte_val(x) >> 3)
290#define pgoff_to_pte(x)		__pte(((x) << 3) | L_PTE_FILE)
291
292#define PTE_FILE_MAX_BITS	29
293
294/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
295/* FIXME: this is not correct */
296#define kern_addr_valid(addr)	(1)
297
298#include <asm-generic/pgtable.h>
299
300/*
301 * We provide our own arch_get_unmapped_area to cope with VIPT caches.
302 */
303#define HAVE_ARCH_UNMAPPED_AREA
304#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
305
306/*
307 * remap a physical page `pfn' of size `size' with page protection `prot'
308 * into virtual address `from'
309 */
310#define io_remap_pfn_range(vma,from,pfn,size,prot) \
311		remap_pfn_range(vma, from, pfn, size, prot)
312
313#define pgtable_cache_init() do { } while (0)
314
315#endif /* !__ASSEMBLY__ */
316
317#endif /* CONFIG_MMU */
318
319#endif /* _ASMARM_PGTABLE_H */
v4.17
  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#define __ARCH_USE_5LEVEL_HACK
 24#include <asm-generic/pgtable-nopud.h>
 25#include <asm/memory.h>
 26#include <asm/pgtable-hwdef.h>
 27
 28
 29#include <asm/tlbflush.h>
 30
 31#ifdef CONFIG_ARM_LPAE
 32#include <asm/pgtable-3level.h>
 33#else
 34#include <asm/pgtable-2level.h>
 35#endif
 36
 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#define VMALLOC_OFFSET		(8*1024*1024)
 46#define VMALLOC_START		(((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
 47#define VMALLOC_END		0xff800000UL
 48
 49#define LIBRARY_TEXT_START	0x0c000000
 50
 51#ifndef __ASSEMBLY__
 52extern void __pte_error(const char *file, int line, pte_t);
 53extern void __pmd_error(const char *file, int line, pmd_t);
 54extern void __pgd_error(const char *file, int line, pgd_t);
 55
 56#define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte)
 57#define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd)
 58#define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, pgd)
 59
 60/*
 61 * This is the lowest virtual address we can permit any user space
 62 * mapping to be mapped at.  This is particularly important for
 63 * non-high vector CPUs.
 64 */
 65#define FIRST_USER_ADDRESS	(PAGE_SIZE * 2)
 66
 67/*
 68 * Use TASK_SIZE as the ceiling argument for free_pgtables() and
 69 * free_pgd_range() to avoid freeing the modules pmd when LPAE is enabled (pmd
 70 * page shared between user and kernel).
 71 */
 72#ifdef CONFIG_ARM_LPAE
 73#define USER_PGTABLES_CEILING	TASK_SIZE
 74#endif
 75
 76/*
 77 * The pgprot_* and protection_map entries will be fixed up in runtime
 78 * to include the cachable and bufferable bits based on memory policy,
 79 * as well as any architecture dependent bits like global/ASID and SMP
 80 * shared mapping bits.
 81 */
 82#define _L_PTE_DEFAULT	L_PTE_PRESENT | L_PTE_YOUNG
 83
 84extern pgprot_t		pgprot_user;
 85extern pgprot_t		pgprot_kernel;
 86extern pgprot_t		pgprot_hyp_device;
 87extern pgprot_t		pgprot_s2;
 88extern pgprot_t		pgprot_s2_device;
 89
 90#define _MOD_PROT(p, b)	__pgprot(pgprot_val(p) | (b))
 91
 92#define PAGE_NONE		_MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY | L_PTE_NONE)
 93#define PAGE_SHARED		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
 94#define PAGE_SHARED_EXEC	_MOD_PROT(pgprot_user, L_PTE_USER)
 95#define PAGE_COPY		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
 96#define PAGE_COPY_EXEC		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
 97#define PAGE_READONLY		_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
 98#define PAGE_READONLY_EXEC	_MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
 99#define PAGE_KERNEL		_MOD_PROT(pgprot_kernel, L_PTE_XN)
100#define PAGE_KERNEL_EXEC	pgprot_kernel
101#define PAGE_HYP		_MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_XN)
102#define PAGE_HYP_EXEC		_MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_RDONLY)
103#define PAGE_HYP_RO		_MOD_PROT(pgprot_kernel, L_PTE_HYP | L_PTE_RDONLY | L_PTE_XN)
104#define PAGE_HYP_DEVICE		_MOD_PROT(pgprot_hyp_device, L_PTE_HYP)
105#define PAGE_S2			_MOD_PROT(pgprot_s2, L_PTE_S2_RDONLY | L_PTE_XN)
106#define PAGE_S2_DEVICE		_MOD_PROT(pgprot_s2_device, L_PTE_S2_RDONLY | L_PTE_XN)
107
108#define __PAGE_NONE		__pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN | L_PTE_NONE)
109#define __PAGE_SHARED		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
110#define __PAGE_SHARED_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER)
111#define __PAGE_COPY		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
112#define __PAGE_COPY_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
113#define __PAGE_READONLY		__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
114#define __PAGE_READONLY_EXEC	__pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
115
116#define __pgprot_modify(prot,mask,bits)		\
117	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
118
119#define pgprot_noncached(prot) \
120	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
121
122#define pgprot_writecombine(prot) \
123	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
124
125#define pgprot_stronglyordered(prot) \
126	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
127
128#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
129#define pgprot_dmacoherent(prot) \
130	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
131#define __HAVE_PHYS_MEM_ACCESS_PROT
132struct file;
133extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
134				     unsigned long size, pgprot_t vma_prot);
135#else
136#define pgprot_dmacoherent(prot) \
137	__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
138#endif
139
140#endif /* __ASSEMBLY__ */
141
142/*
143 * The table below defines the page protection levels that we insert into our
144 * Linux page table version.  These get translated into the best that the
145 * architecture can perform.  Note that on most ARM hardware:
146 *  1) We cannot do execute protection
147 *  2) If we could do execute protection, then read is implied
148 *  3) write implies read permissions
149 */
150#define __P000  __PAGE_NONE
151#define __P001  __PAGE_READONLY
152#define __P010  __PAGE_COPY
153#define __P011  __PAGE_COPY
154#define __P100  __PAGE_READONLY_EXEC
155#define __P101  __PAGE_READONLY_EXEC
156#define __P110  __PAGE_COPY_EXEC
157#define __P111  __PAGE_COPY_EXEC
158
159#define __S000  __PAGE_NONE
160#define __S001  __PAGE_READONLY
161#define __S010  __PAGE_SHARED
162#define __S011  __PAGE_SHARED
163#define __S100  __PAGE_READONLY_EXEC
164#define __S101  __PAGE_READONLY_EXEC
165#define __S110  __PAGE_SHARED_EXEC
166#define __S111  __PAGE_SHARED_EXEC
167
168#ifndef __ASSEMBLY__
169/*
170 * ZERO_PAGE is a global shared page that is always zero: used
171 * for zero-mapped memory areas etc..
172 */
173extern struct page *empty_zero_page;
174#define ZERO_PAGE(vaddr)	(empty_zero_page)
175
176
177extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
178
179/* to find an entry in a page-table-directory */
180#define pgd_index(addr)		((addr) >> PGDIR_SHIFT)
181
182#define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
183
184/* to find an entry in a kernel page-table-directory */
185#define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
186
187#define pmd_none(pmd)		(!pmd_val(pmd))
 
188
189static inline pte_t *pmd_page_vaddr(pmd_t pmd)
190{
191	return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
192}
193
194#define pmd_page(pmd)		pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
195
196#ifndef CONFIG_HIGHPTE
197#define __pte_map(pmd)		pmd_page_vaddr(*(pmd))
198#define __pte_unmap(pte)	do { } while (0)
199#else
200#define __pte_map(pmd)		(pte_t *)kmap_atomic(pmd_page(*(pmd)))
201#define __pte_unmap(pte)	kunmap_atomic(pte)
202#endif
203
204#define pte_index(addr)		(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
205
206#define pte_offset_kernel(pmd,addr)	(pmd_page_vaddr(*(pmd)) + pte_index(addr))
207
208#define pte_offset_map(pmd,addr)	(__pte_map(pmd) + pte_index(addr))
209#define pte_unmap(pte)			__pte_unmap(pte)
210
211#define pte_pfn(pte)		((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
212#define pfn_pte(pfn,prot)	__pte(__pfn_to_phys(pfn) | pgprot_val(prot))
213
214#define pte_page(pte)		pfn_to_page(pte_pfn(pte))
215#define mk_pte(page,prot)	pfn_pte(page_to_pfn(page), prot)
216
217#define pte_clear(mm,addr,ptep)	set_pte_ext(ptep, __pte(0), 0)
218
219#define pte_isset(pte, val)	((u32)(val) == (val) ? pte_val(pte) & (val) \
220						: !!(pte_val(pte) & (val)))
221#define pte_isclear(pte, val)	(!(pte_val(pte) & (val)))
222
223#define pte_none(pte)		(!pte_val(pte))
224#define pte_present(pte)	(pte_isset((pte), L_PTE_PRESENT))
225#define pte_valid(pte)		(pte_isset((pte), L_PTE_VALID))
226#define pte_accessible(mm, pte)	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
227#define pte_write(pte)		(pte_isclear((pte), L_PTE_RDONLY))
228#define pte_dirty(pte)		(pte_isset((pte), L_PTE_DIRTY))
229#define pte_young(pte)		(pte_isset((pte), L_PTE_YOUNG))
230#define pte_exec(pte)		(pte_isclear((pte), L_PTE_XN))
231
232#define pte_valid_user(pte)	\
233	(pte_valid(pte) && pte_isset((pte), L_PTE_USER) && pte_young(pte))
234
235static inline bool pte_access_permitted(pte_t pte, bool write)
236{
237	pteval_t mask = L_PTE_PRESENT | L_PTE_USER;
238	pteval_t needed = mask;
239
240	if (write)
241		mask |= L_PTE_RDONLY;
242
243	return (pte_val(pte) & mask) == needed;
244}
245#define pte_access_permitted pte_access_permitted
246
247#if __LINUX_ARM_ARCH__ < 6
248static inline void __sync_icache_dcache(pte_t pteval)
249{
250}
251#else
252extern void __sync_icache_dcache(pte_t pteval);
253#endif
254
255static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
256			      pte_t *ptep, pte_t pteval)
257{
258	unsigned long ext = 0;
259
260	if (addr < TASK_SIZE && pte_valid_user(pteval)) {
261		if (!pte_special(pteval))
262			__sync_icache_dcache(pteval);
263		ext |= PTE_EXT_NG;
264	}
265
266	set_pte_ext(ptep, pteval, ext);
267}
268
269static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
270{
271	pte_val(pte) &= ~pgprot_val(prot);
272	return pte;
273}
274
275static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
276{
277	pte_val(pte) |= pgprot_val(prot);
278	return pte;
279}
280
281static inline pte_t pte_wrprotect(pte_t pte)
282{
283	return set_pte_bit(pte, __pgprot(L_PTE_RDONLY));
284}
285
286static inline pte_t pte_mkwrite(pte_t pte)
287{
288	return clear_pte_bit(pte, __pgprot(L_PTE_RDONLY));
289}
290
291static inline pte_t pte_mkclean(pte_t pte)
292{
293	return clear_pte_bit(pte, __pgprot(L_PTE_DIRTY));
294}
295
296static inline pte_t pte_mkdirty(pte_t pte)
297{
298	return set_pte_bit(pte, __pgprot(L_PTE_DIRTY));
299}
300
301static inline pte_t pte_mkold(pte_t pte)
302{
303	return clear_pte_bit(pte, __pgprot(L_PTE_YOUNG));
304}
305
306static inline pte_t pte_mkyoung(pte_t pte)
307{
308	return set_pte_bit(pte, __pgprot(L_PTE_YOUNG));
309}
 
 
310
311static inline pte_t pte_mkexec(pte_t pte)
312{
313	return clear_pte_bit(pte, __pgprot(L_PTE_XN));
314}
315
316static inline pte_t pte_mknexec(pte_t pte)
317{
318	return set_pte_bit(pte, __pgprot(L_PTE_XN));
319}
320
321static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
322{
323	const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER |
324		L_PTE_NONE | L_PTE_VALID;
325	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
326	return pte;
327}
328
329/*
330 * Encode and decode a swap entry.  Swap entries are stored in the Linux
331 * page tables as follows:
332 *
333 *   3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
334 *   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
335 *   <--------------- offset ------------------------> < type -> 0 0
336 *
337 * This gives us up to 31 swap files and 128GB per swap file.  Note that
338 * the offset field is always non-zero.
339 */
340#define __SWP_TYPE_SHIFT	2
341#define __SWP_TYPE_BITS		5
342#define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
343#define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
344
345#define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
346#define __swp_offset(x)		((x).val >> __SWP_OFFSET_SHIFT)
347#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
348
349#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
350#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
351
352/*
353 * It is an error for the kernel to have more swap files than we can
354 * encode in the PTEs.  This ensures that we know when MAX_SWAPFILES
355 * is increased beyond what we presently support.
356 */
357#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
358
 
 
 
 
 
 
 
 
 
 
 
 
 
 
359/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
360/* FIXME: this is not correct */
361#define kern_addr_valid(addr)	(1)
362
363#include <asm-generic/pgtable.h>
364
365/*
366 * We provide our own arch_get_unmapped_area to cope with VIPT caches.
367 */
368#define HAVE_ARCH_UNMAPPED_AREA
369#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 
 
 
 
 
 
 
370
371#define pgtable_cache_init() do { } while (0)
372
373#endif /* !__ASSEMBLY__ */
374
375#endif /* CONFIG_MMU */
376
377#endif /* _ASMARM_PGTABLE_H */