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/proc-fns.h>
18 #include <asm-generic/4level-fixup.h>
19 #include "pgtable-nommu.h"
23 #include <asm-generic/pgtable-nopud.h>
24 #include <asm/memory.h>
25 #include <asm/pgtable-hwdef.h>
28 #include <asm/tlbflush.h>
30 #ifdef CONFIG_ARM_LPAE
31 #include <asm/pgtable-3level.h>
33 #include <asm/pgtable-2level.h>
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. ;)
44 #define VMALLOC_OFFSET (8*1024*1024)
45 #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
46 #define VMALLOC_END 0xff000000UL
48 #define LIBRARY_TEXT_START 0x0c000000
51 extern void __pte_error(const char *file, int line, pte_t);
52 extern void __pmd_error(const char *file, int line, pmd_t);
53 extern void __pgd_error(const char *file, int line, pgd_t);
55 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte)
56 #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd)
57 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd)
60 * This is the lowest virtual address we can permit any user space
61 * mapping to be mapped at. This is particularly important for
62 * non-high vector CPUs.
64 #define FIRST_USER_ADDRESS PAGE_SIZE
66 /* OMAP hack - high vector CPUs, so don't limit it */
67 #ifdef CONFIG_ARCH_OMAP
68 #undef FIRST_USER_ADDRESS
69 #define FIRST_USER_ADDRESS 0
73 * The pgprot_* and protection_map entries will be fixed up in runtime
74 * to include the cachable and bufferable bits based on memory policy,
75 * as well as any architecture dependent bits like global/ASID and SMP
76 * shared mapping bits.
78 #define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG
80 extern pgprot_t pgprot_user;
81 extern pgprot_t pgprot_kernel;
83 #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
85 #define PAGE_NONE _MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY | L_PTE_NONE)
86 #define PAGE_SHARED _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
87 #define PAGE_SHARED_EXEC _MOD_PROT(pgprot_user, L_PTE_USER)
88 #define PAGE_COPY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
89 #define PAGE_COPY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
90 #define PAGE_READONLY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
91 #define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
92 #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
93 #define PAGE_KERNEL_EXEC pgprot_kernel
95 #define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN | L_PTE_NONE)
96 #define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
97 #define __PAGE_SHARED_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER)
98 #define __PAGE_COPY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
99 #define __PAGE_COPY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
100 #define __PAGE_READONLY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
101 #define __PAGE_READONLY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
103 #define __pgprot_modify(prot,mask,bits) \
104 __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
106 #define pgprot_noncached(prot) \
107 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
109 #define pgprot_writecombine(prot) \
110 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
112 #define pgprot_stronglyordered(prot) \
113 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
115 #define pgprot_writethrough(prot) \
116 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_WRITETHROUGH)
118 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
119 #define pgprot_dmacoherent(prot) \
120 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
121 #define __HAVE_PHYS_MEM_ACCESS_PROT
123 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
124 unsigned long size, pgprot_t vma_prot);
126 #define pgprot_dmacoherent(prot) \
127 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
130 #endif /* __ASSEMBLY__ */
133 * The table below defines the page protection levels that we insert into our
134 * Linux page table version. These get translated into the best that the
135 * architecture can perform. Note that on most ARM hardware:
136 * 1) We cannot do execute protection
137 * 2) If we could do execute protection, then read is implied
138 * 3) write implies read permissions
140 #define __P000 __PAGE_NONE
141 #define __P001 __PAGE_READONLY
142 #define __P010 __PAGE_COPY
143 #define __P011 __PAGE_COPY
144 #define __P100 __PAGE_READONLY_EXEC
145 #define __P101 __PAGE_READONLY_EXEC
146 #define __P110 __PAGE_COPY_EXEC
147 #define __P111 __PAGE_COPY_EXEC
149 #define __S000 __PAGE_NONE
150 #define __S001 __PAGE_READONLY
151 #define __S010 __PAGE_SHARED
152 #define __S011 __PAGE_SHARED
153 #define __S100 __PAGE_READONLY_EXEC
154 #define __S101 __PAGE_READONLY_EXEC
155 #define __S110 __PAGE_SHARED_EXEC
156 #define __S111 __PAGE_SHARED_EXEC
160 * ZERO_PAGE is a global shared page that is always zero: used
161 * for zero-mapped memory areas etc..
163 extern struct page *empty_zero_page;
164 #define ZERO_PAGE(vaddr) (empty_zero_page)
167 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
169 /* to find an entry in a page-table-directory */
170 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
172 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
174 /* to find an entry in a kernel page-table-directory */
175 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
177 #define pmd_none(pmd) (!pmd_val(pmd))
179 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
181 #ifdef SYS_SUPPORTS_HUGETLBFS
182 if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_SECT)
183 return __va(pmd_val(pmd) & HPAGE_MASK);
186 return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
189 #ifndef CONFIG_HIGHPTE
190 #define __pte_map(pmd) pmd_page_vaddr(*(pmd))
191 #define __pte_unmap(pte) do { } while (0)
193 #define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd)))
194 #define __pte_unmap(pte) kunmap_atomic(pte)
197 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
199 #define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr))
201 #define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr))
202 #define pte_unmap(pte) __pte_unmap(pte)
204 #define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
205 #define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
207 #define pte_page(pte) pfn_to_page(pte_pfn(pte))
208 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot)
210 #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0)
212 #define pte_none(pte) (!pte_val(pte))
213 #define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT)
214 #define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY))
215 #define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY)
216 #define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG)
217 #define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN))
218 #define pte_special(pte) (0)
220 #define pte_present_user(pte) (pte_present(pte) && (pte_val(pte) & L_PTE_USER))
222 #if __LINUX_ARM_ARCH__ < 6
223 static inline void __sync_icache_dcache(pte_t pteval)
227 extern void __sync_icache_dcache(pte_t pteval);
230 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
231 pte_t *ptep, pte_t pteval)
233 unsigned long ext = 0;
235 if (addr < TASK_SIZE && pte_present_user(pteval)) {
236 __sync_icache_dcache(pteval);
240 set_pte_ext(ptep, pteval, ext);
243 #define PTE_BIT_FUNC(fn,op) \
244 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
246 PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY);
247 PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY);
248 PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY);
249 PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY);
250 PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG);
251 PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG);
252 PTE_BIT_FUNC(mkexec, &= ~L_PTE_XN);
253 PTE_BIT_FUNC(mknexec, |= L_PTE_XN);
255 static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
257 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
259 const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER | L_PTE_NONE;
260 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
265 * Encode and decode a swap entry. Swap entries are stored in the Linux
266 * page tables as follows:
268 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
269 * 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
270 * <--------------- offset ----------------------> < type -> 0 0 0
272 * This gives us up to 31 swap files and 64GB per swap file. Note that
273 * the offset field is always non-zero.
275 #define __SWP_TYPE_SHIFT 3
276 #define __SWP_TYPE_BITS 5
277 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
278 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
280 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
281 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
282 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
284 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
285 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
288 * It is an error for the kernel to have more swap files than we can
289 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES
290 * is increased beyond what we presently support.
292 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
295 * Encode and decode a file entry. File entries are stored in the Linux
296 * page tables as follows:
298 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
299 * 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
300 * <----------------------- offset ------------------------> 1 0 0
302 #define pte_file(pte) (pte_val(pte) & L_PTE_FILE)
303 #define pte_to_pgoff(x) (pte_val(x) >> 3)
304 #define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE)
306 #define PTE_FILE_MAX_BITS 29
308 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
309 /* FIXME: this is not correct */
310 #define kern_addr_valid(addr) (1)
312 #include <asm-generic/pgtable.h>
315 * We provide our own arch_get_unmapped_area to cope with VIPT caches.
317 #define HAVE_ARCH_UNMAPPED_AREA
320 * remap a physical page `pfn' of size `size' with page protection `prot'
321 * into virtual address `from'
323 #define io_remap_pfn_range(vma,from,pfn,size,prot) \
324 remap_pfn_range(vma, from, pfn, size, prot)
326 #define pgtable_cache_init() do { } while (0)
328 #endif /* !__ASSEMBLY__ */
330 #endif /* CONFIG_MMU */
332 #endif /* _ASMARM_PGTABLE_H */