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 <mach/vmalloc.h>
25 #include <asm/pgtable-hwdef.h>
27 #include <asm/pgtable-2level.h>
30 * Just any arbitrary offset to the start of the vmalloc VM area: the
31 * current 8MB value just means that there will be a 8MB "hole" after the
32 * physical memory until the kernel virtual memory starts. That means that
33 * any out-of-bounds memory accesses will hopefully be caught.
34 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
35 * area for the same reason. ;)
37 * Note that platforms may override VMALLOC_START, but they must provide
38 * VMALLOC_END. VMALLOC_END defines the (exclusive) limit of this space,
39 * which may not overlap IO space.
42 #define VMALLOC_OFFSET (8*1024*1024)
43 #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
46 #define LIBRARY_TEXT_START 0x0c000000
49 extern void __pte_error(const char *file, int line, pte_t);
50 extern void __pmd_error(const char *file, int line, pmd_t);
51 extern void __pgd_error(const char *file, int line, pgd_t);
53 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte)
54 #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd)
55 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd)
58 * This is the lowest virtual address we can permit any user space
59 * mapping to be mapped at. This is particularly important for
60 * non-high vector CPUs.
62 #define FIRST_USER_ADDRESS PAGE_SIZE
65 * The pgprot_* and protection_map entries will be fixed up in runtime
66 * to include the cachable and bufferable bits based on memory policy,
67 * as well as any architecture dependent bits like global/ASID and SMP
68 * shared mapping bits.
70 #define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG
72 extern pgprot_t pgprot_user;
73 extern pgprot_t pgprot_kernel;
75 #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
77 #define PAGE_NONE _MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY)
78 #define PAGE_SHARED _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
79 #define PAGE_SHARED_EXEC _MOD_PROT(pgprot_user, L_PTE_USER)
80 #define PAGE_COPY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
81 #define PAGE_COPY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
82 #define PAGE_READONLY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
83 #define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
84 #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
85 #define PAGE_KERNEL_EXEC pgprot_kernel
87 #define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN)
88 #define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
89 #define __PAGE_SHARED_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER)
90 #define __PAGE_COPY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
91 #define __PAGE_COPY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
92 #define __PAGE_READONLY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
93 #define __PAGE_READONLY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
95 #define __pgprot_modify(prot,mask,bits) \
96 __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
98 #define pgprot_noncached(prot) \
99 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
101 #define pgprot_writecombine(prot) \
102 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
104 #define pgprot_stronglyordered(prot) \
105 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
107 #define pgprot_writethrough(prot) \
108 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_WRITETHROUGH)
110 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
111 #define pgprot_dmacoherent(prot) \
112 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
113 #define __HAVE_PHYS_MEM_ACCESS_PROT
115 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
116 unsigned long size, pgprot_t vma_prot);
118 #define pgprot_dmacoherent(prot) \
119 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
122 #endif /* __ASSEMBLY__ */
125 * The table below defines the page protection levels that we insert into our
126 * Linux page table version. These get translated into the best that the
127 * architecture can perform. Note that on most ARM hardware:
128 * 1) We cannot do execute protection
129 * 2) If we could do execute protection, then read is implied
130 * 3) write implies read permissions
132 #define __P000 __PAGE_NONE
133 #define __P001 __PAGE_READONLY
134 #define __P010 __PAGE_COPY
135 #define __P011 __PAGE_COPY
136 #define __P100 __PAGE_READONLY_EXEC
137 #define __P101 __PAGE_READONLY_EXEC
138 #define __P110 __PAGE_COPY_EXEC
139 #define __P111 __PAGE_COPY_EXEC
141 #define __S000 __PAGE_NONE
142 #define __S001 __PAGE_READONLY
143 #define __S010 __PAGE_SHARED
144 #define __S011 __PAGE_SHARED
145 #define __S100 __PAGE_READONLY_EXEC
146 #define __S101 __PAGE_READONLY_EXEC
147 #define __S110 __PAGE_SHARED_EXEC
148 #define __S111 __PAGE_SHARED_EXEC
152 * ZERO_PAGE is a global shared page that is always zero: used
153 * for zero-mapped memory areas etc..
155 extern struct page *empty_zero_page;
156 #define ZERO_PAGE(vaddr) (empty_zero_page)
159 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
161 /* to find an entry in a page-table-directory */
162 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
164 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
166 /* to find an entry in a kernel page-table-directory */
167 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
170 * The "pgd_xxx()" functions here are trivial for a folded two-level
171 * setup: the pgd is never bad, and a pmd always exists (as it's folded
172 * into the pgd entry)
174 #define pgd_none(pgd) (0)
175 #define pgd_bad(pgd) (0)
176 #define pgd_present(pgd) (1)
177 #define pgd_clear(pgdp) do { } while (0)
178 #define set_pgd(pgd,pgdp) do { } while (0)
179 #define set_pud(pud,pudp) do { } while (0)
182 /* Find an entry in the second-level page table.. */
183 #define pmd_offset(dir, addr) ((pmd_t *)(dir))
185 #define pmd_none(pmd) (!pmd_val(pmd))
186 #define pmd_present(pmd) (pmd_val(pmd))
187 #define pmd_bad(pmd) (pmd_val(pmd) & 2)
189 #define copy_pmd(pmdpd,pmdps) \
191 pmdpd[0] = pmdps[0]; \
192 pmdpd[1] = pmdps[1]; \
193 flush_pmd_entry(pmdpd); \
196 #define pmd_clear(pmdp) \
198 pmdp[0] = __pmd(0); \
199 pmdp[1] = __pmd(0); \
200 clean_pmd_entry(pmdp); \
203 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
205 return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
208 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
210 /* we don't need complex calculations here as the pmd is folded into the pgd */
211 #define pmd_addr_end(addr,end) (end)
214 #ifndef CONFIG_HIGHPTE
215 #define __pte_map(pmd) pmd_page_vaddr(*(pmd))
216 #define __pte_unmap(pte) do { } while (0)
218 #define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd)))
219 #define __pte_unmap(pte) kunmap_atomic(pte)
222 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
224 #define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr))
226 #define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr))
227 #define pte_unmap(pte) __pte_unmap(pte)
229 #define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
230 #define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
232 #define pte_page(pte) pfn_to_page(pte_pfn(pte))
233 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot)
235 #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext)
236 #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0)
238 #if __LINUX_ARM_ARCH__ < 6
239 static inline void __sync_icache_dcache(pte_t pteval)
243 extern void __sync_icache_dcache(pte_t pteval);
246 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
247 pte_t *ptep, pte_t pteval)
249 if (addr >= TASK_SIZE)
250 set_pte_ext(ptep, pteval, 0);
252 __sync_icache_dcache(pteval);
253 set_pte_ext(ptep, pteval, PTE_EXT_NG);
257 #define pte_none(pte) (!pte_val(pte))
258 #define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT)
259 #define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY))
260 #define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY)
261 #define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG)
262 #define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN))
263 #define pte_special(pte) (0)
265 #define pte_present_user(pte) \
266 ((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \
267 (L_PTE_PRESENT | L_PTE_USER))
269 #define PTE_BIT_FUNC(fn,op) \
270 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
272 PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY);
273 PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY);
274 PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY);
275 PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY);
276 PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG);
277 PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG);
279 static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
281 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
283 const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER;
284 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
289 * Encode and decode a swap entry. Swap entries are stored in the Linux
290 * page tables as follows:
292 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
293 * 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
294 * <--------------- offset --------------------> <- type --> 0 0 0
296 * This gives us up to 63 swap files and 32GB per swap file. Note that
297 * the offset field is always non-zero.
299 #define __SWP_TYPE_SHIFT 3
300 #define __SWP_TYPE_BITS 6
301 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
302 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
304 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
305 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
306 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
308 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
309 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
312 * It is an error for the kernel to have more swap files than we can
313 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES
314 * is increased beyond what we presently support.
316 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
319 * Encode and decode a file entry. File entries are stored in the Linux
320 * page tables as follows:
322 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
323 * 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
324 * <----------------------- offset ------------------------> 1 0 0
326 #define pte_file(pte) (pte_val(pte) & L_PTE_FILE)
327 #define pte_to_pgoff(x) (pte_val(x) >> 3)
328 #define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE)
330 #define PTE_FILE_MAX_BITS 29
332 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
333 /* FIXME: this is not correct */
334 #define kern_addr_valid(addr) (1)
336 #include <asm-generic/pgtable.h>
339 * We provide our own arch_get_unmapped_area to cope with VIPT caches.
341 #define HAVE_ARCH_UNMAPPED_AREA
344 * remap a physical page `pfn' of size `size' with page protection `prot'
345 * into virtual address `from'
347 #define io_remap_pfn_range(vma,from,pfn,size,prot) \
348 remap_pfn_range(vma, from, pfn, size, prot)
350 #define pgtable_cache_init() do { } while (0)
352 void identity_mapping_add(pgd_t *, unsigned long, unsigned long);
353 void identity_mapping_del(pgd_t *, unsigned long, unsigned long);
355 #endif /* !__ASSEMBLY__ */
357 #endif /* CONFIG_MMU */
359 #endif /* _ASMARM_PGTABLE_H */