2 * arch/arm/include/asm/pgtable.h
4 * Copyright (C) 1995-2002 Russell King
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.
10 #ifndef _ASMARM_PGTABLE_H
11 #define _ASMARM_PGTABLE_H
13 #include <linux/const.h>
14 #include <asm-generic/4level-fixup.h>
15 #include <asm/proc-fns.h>
19 #include "pgtable-nommu.h"
23 #include <asm/memory.h>
24 #include <asm/pgtable-hwdef.h>
26 #include <asm/pgtable-2level.h>
29 * Just any arbitrary offset to the start of the vmalloc VM area: the
30 * current 8MB value just means that there will be a 8MB "hole" after the
31 * physical memory until the kernel virtual memory starts. That means that
32 * any out-of-bounds memory accesses will hopefully be caught.
33 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
34 * area for the same reason. ;)
36 #define VMALLOC_OFFSET (8*1024*1024)
37 #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
38 #define VMALLOC_END 0xff000000UL
40 #define LIBRARY_TEXT_START 0x0c000000
43 extern void __pte_error(const char *file, int line, pte_t);
44 extern void __pmd_error(const char *file, int line, pmd_t);
45 extern void __pgd_error(const char *file, int line, pgd_t);
47 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte)
48 #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd)
49 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd)
52 * This is the lowest virtual address we can permit any user space
53 * mapping to be mapped at. This is particularly important for
54 * non-high vector CPUs.
56 #define FIRST_USER_ADDRESS PAGE_SIZE
59 * The pgprot_* and protection_map entries will be fixed up in runtime
60 * to include the cachable and bufferable bits based on memory policy,
61 * as well as any architecture dependent bits like global/ASID and SMP
62 * shared mapping bits.
64 #define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG
66 extern pgprot_t pgprot_user;
67 extern pgprot_t pgprot_kernel;
69 #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
71 #define PAGE_NONE _MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY)
72 #define PAGE_SHARED _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
73 #define PAGE_SHARED_EXEC _MOD_PROT(pgprot_user, L_PTE_USER)
74 #define PAGE_COPY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
75 #define PAGE_COPY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
76 #define PAGE_READONLY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
77 #define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
78 #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
79 #define PAGE_KERNEL_EXEC pgprot_kernel
81 #define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN)
82 #define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
83 #define __PAGE_SHARED_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER)
84 #define __PAGE_COPY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
85 #define __PAGE_COPY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
86 #define __PAGE_READONLY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
87 #define __PAGE_READONLY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
89 #define __pgprot_modify(prot,mask,bits) \
90 __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
92 #define pgprot_noncached(prot) \
93 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
95 #define pgprot_writecombine(prot) \
96 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
98 #define pgprot_stronglyordered(prot) \
99 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
101 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
102 #define pgprot_dmacoherent(prot) \
103 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
104 #define __HAVE_PHYS_MEM_ACCESS_PROT
106 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
107 unsigned long size, pgprot_t vma_prot);
109 #define pgprot_dmacoherent(prot) \
110 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
113 #endif /* __ASSEMBLY__ */
116 * The table below defines the page protection levels that we insert into our
117 * Linux page table version. These get translated into the best that the
118 * architecture can perform. Note that on most ARM hardware:
119 * 1) We cannot do execute protection
120 * 2) If we could do execute protection, then read is implied
121 * 3) write implies read permissions
123 #define __P000 __PAGE_NONE
124 #define __P001 __PAGE_READONLY
125 #define __P010 __PAGE_COPY
126 #define __P011 __PAGE_COPY
127 #define __P100 __PAGE_READONLY_EXEC
128 #define __P101 __PAGE_READONLY_EXEC
129 #define __P110 __PAGE_COPY_EXEC
130 #define __P111 __PAGE_COPY_EXEC
132 #define __S000 __PAGE_NONE
133 #define __S001 __PAGE_READONLY
134 #define __S010 __PAGE_SHARED
135 #define __S011 __PAGE_SHARED
136 #define __S100 __PAGE_READONLY_EXEC
137 #define __S101 __PAGE_READONLY_EXEC
138 #define __S110 __PAGE_SHARED_EXEC
139 #define __S111 __PAGE_SHARED_EXEC
143 * ZERO_PAGE is a global shared page that is always zero: used
144 * for zero-mapped memory areas etc..
146 extern struct page *empty_zero_page;
147 #define ZERO_PAGE(vaddr) (empty_zero_page)
150 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
152 /* to find an entry in a page-table-directory */
153 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
155 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
157 /* to find an entry in a kernel page-table-directory */
158 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
161 * The "pgd_xxx()" functions here are trivial for a folded two-level
162 * setup: the pgd is never bad, and a pmd always exists (as it's folded
163 * into the pgd entry)
165 #define pgd_none(pgd) (0)
166 #define pgd_bad(pgd) (0)
167 #define pgd_present(pgd) (1)
168 #define pgd_clear(pgdp) do { } while (0)
169 #define set_pgd(pgd,pgdp) do { } while (0)
170 #define set_pud(pud,pudp) do { } while (0)
173 /* Find an entry in the second-level page table.. */
174 #define pmd_offset(dir, addr) ((pmd_t *)(dir))
176 #define pmd_none(pmd) (!pmd_val(pmd))
177 #define pmd_present(pmd) (pmd_val(pmd))
178 #define pmd_bad(pmd) (pmd_val(pmd) & 2)
180 #define copy_pmd(pmdpd,pmdps) \
182 pmdpd[0] = pmdps[0]; \
183 pmdpd[1] = pmdps[1]; \
184 flush_pmd_entry(pmdpd); \
187 #define pmd_clear(pmdp) \
189 pmdp[0] = __pmd(0); \
190 pmdp[1] = __pmd(0); \
191 clean_pmd_entry(pmdp); \
194 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
196 return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
199 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
201 /* we don't need complex calculations here as the pmd is folded into the pgd */
202 #define pmd_addr_end(addr,end) (end)
205 #ifndef CONFIG_HIGHPTE
206 #define __pte_map(pmd) pmd_page_vaddr(*(pmd))
207 #define __pte_unmap(pte) do { } while (0)
209 #define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd)))
210 #define __pte_unmap(pte) kunmap_atomic(pte)
213 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
215 #define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr))
217 #define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr))
218 #define pte_unmap(pte) __pte_unmap(pte)
220 #define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
221 #define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
223 #define pte_page(pte) pfn_to_page(pte_pfn(pte))
224 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot)
226 #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext)
227 #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0)
229 #if __LINUX_ARM_ARCH__ < 6
230 static inline void __sync_icache_dcache(pte_t pteval)
234 extern void __sync_icache_dcache(pte_t pteval);
237 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
238 pte_t *ptep, pte_t pteval)
240 if (addr >= TASK_SIZE)
241 set_pte_ext(ptep, pteval, 0);
243 __sync_icache_dcache(pteval);
244 set_pte_ext(ptep, pteval, PTE_EXT_NG);
248 #define pte_none(pte) (!pte_val(pte))
249 #define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT)
250 #define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY))
251 #define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY)
252 #define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG)
253 #define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN))
254 #define pte_special(pte) (0)
256 #define pte_present_user(pte) \
257 ((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \
258 (L_PTE_PRESENT | L_PTE_USER))
260 #define PTE_BIT_FUNC(fn,op) \
261 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
263 PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY);
264 PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY);
265 PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY);
266 PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY);
267 PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG);
268 PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG);
270 static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
272 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
274 const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER;
275 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
280 * Encode and decode a swap entry. Swap entries are stored in the Linux
281 * page tables as follows:
283 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
284 * 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
285 * <--------------- offset --------------------> <- type --> 0 0 0
287 * This gives us up to 63 swap files and 32GB per swap file. Note that
288 * the offset field is always non-zero.
290 #define __SWP_TYPE_SHIFT 3
291 #define __SWP_TYPE_BITS 6
292 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
293 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
295 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
296 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
297 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
299 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
300 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
303 * It is an error for the kernel to have more swap files than we can
304 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES
305 * is increased beyond what we presently support.
307 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
310 * Encode and decode a file entry. File entries are stored in the Linux
311 * page tables as follows:
313 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
314 * 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
315 * <----------------------- offset ------------------------> 1 0 0
317 #define pte_file(pte) (pte_val(pte) & L_PTE_FILE)
318 #define pte_to_pgoff(x) (pte_val(x) >> 3)
319 #define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE)
321 #define PTE_FILE_MAX_BITS 29
323 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
324 /* FIXME: this is not correct */
325 #define kern_addr_valid(addr) (1)
327 #include <asm-generic/pgtable.h>
330 * We provide our own arch_get_unmapped_area to cope with VIPT caches.
332 #define HAVE_ARCH_UNMAPPED_AREA
335 * remap a physical page `pfn' of size `size' with page protection `prot'
336 * into virtual address `from'
338 #define io_remap_pfn_range(vma,from,pfn,size,prot) \
339 remap_pfn_range(vma, from, pfn, size, prot)
341 #define pgtable_cache_init() do { } while (0)
343 void identity_mapping_add(pgd_t *, unsigned long, unsigned long);
344 void identity_mapping_del(pgd_t *, unsigned long, unsigned long);
346 #endif /* !__ASSEMBLY__ */
348 #endif /* CONFIG_MMU */
350 #endif /* _ASMARM_PGTABLE_H */