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-generic/4level-fixup.h> 15 #include <asm/proc-fns.h> 16 17 #ifndef CONFIG_MMU 18 19 #include "pgtable-nommu.h" 20 21 #else 22 23 #include <asm/memory.h> 24 #include <mach/vmalloc.h> 25 #include <asm/pgtable-hwdef.h> 26 27 #include <asm/pgtable-2level.h> 28 29 /* 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. ;) 36 * 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. 40 */ 41 #ifndef VMALLOC_START 42 #define VMALLOC_OFFSET (8*1024*1024) 43 #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) 44 #endif 45 46 #define LIBRARY_TEXT_START 0x0c000000 47 48 #ifndef __ASSEMBLY__ 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); 52 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) 56 57 /* 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. 61 */ 62 #define FIRST_USER_ADDRESS PAGE_SIZE 63 64 /* 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. 69 */ 70 #define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG 71 72 extern pgprot_t pgprot_user; 73 extern pgprot_t pgprot_kernel; 74 75 #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b)) 76 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 86 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) 94 95 #define __pgprot_modify(prot,mask,bits) \ 96 __pgprot((pgprot_val(prot) & ~(mask)) | (bits)) 97 98 #define pgprot_noncached(prot) \ 99 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED) 100 101 #define pgprot_writecombine(prot) \ 102 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE) 103 104 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE 105 #define pgprot_dmacoherent(prot) \ 106 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN) 107 #define __HAVE_PHYS_MEM_ACCESS_PROT 108 struct file; 109 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 110 unsigned long size, pgprot_t vma_prot); 111 #else 112 #define pgprot_dmacoherent(prot) \ 113 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN) 114 #endif 115 116 #endif /* __ASSEMBLY__ */ 117 118 /* 119 * The table below defines the page protection levels that we insert into our 120 * Linux page table version. These get translated into the best that the 121 * architecture can perform. Note that on most ARM hardware: 122 * 1) We cannot do execute protection 123 * 2) If we could do execute protection, then read is implied 124 * 3) write implies read permissions 125 */ 126 #define __P000 __PAGE_NONE 127 #define __P001 __PAGE_READONLY 128 #define __P010 __PAGE_COPY 129 #define __P011 __PAGE_COPY 130 #define __P100 __PAGE_READONLY_EXEC 131 #define __P101 __PAGE_READONLY_EXEC 132 #define __P110 __PAGE_COPY_EXEC 133 #define __P111 __PAGE_COPY_EXEC 134 135 #define __S000 __PAGE_NONE 136 #define __S001 __PAGE_READONLY 137 #define __S010 __PAGE_SHARED 138 #define __S011 __PAGE_SHARED 139 #define __S100 __PAGE_READONLY_EXEC 140 #define __S101 __PAGE_READONLY_EXEC 141 #define __S110 __PAGE_SHARED_EXEC 142 #define __S111 __PAGE_SHARED_EXEC 143 144 #ifndef __ASSEMBLY__ 145 /* 146 * ZERO_PAGE is a global shared page that is always zero: used 147 * for zero-mapped memory areas etc.. 148 */ 149 extern struct page *empty_zero_page; 150 #define ZERO_PAGE(vaddr) (empty_zero_page) 151 152 153 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 154 155 /* to find an entry in a page-table-directory */ 156 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT) 157 158 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr)) 159 160 /* to find an entry in a kernel page-table-directory */ 161 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) 162 163 /* 164 * The "pgd_xxx()" functions here are trivial for a folded two-level 165 * setup: the pgd is never bad, and a pmd always exists (as it's folded 166 * into the pgd entry) 167 */ 168 #define pgd_none(pgd) (0) 169 #define pgd_bad(pgd) (0) 170 #define pgd_present(pgd) (1) 171 #define pgd_clear(pgdp) do { } while (0) 172 #define set_pgd(pgd,pgdp) do { } while (0) 173 #define set_pud(pud,pudp) do { } while (0) 174 175 176 /* Find an entry in the second-level page table.. */ 177 #define pmd_offset(dir, addr) ((pmd_t *)(dir)) 178 179 #define pmd_none(pmd) (!pmd_val(pmd)) 180 #define pmd_present(pmd) (pmd_val(pmd)) 181 #define pmd_bad(pmd) (pmd_val(pmd) & 2) 182 183 #define copy_pmd(pmdpd,pmdps) \ 184 do { \ 185 pmdpd[0] = pmdps[0]; \ 186 pmdpd[1] = pmdps[1]; \ 187 flush_pmd_entry(pmdpd); \ 188 } while (0) 189 190 #define pmd_clear(pmdp) \ 191 do { \ 192 pmdp[0] = __pmd(0); \ 193 pmdp[1] = __pmd(0); \ 194 clean_pmd_entry(pmdp); \ 195 } while (0) 196 197 static inline pte_t *pmd_page_vaddr(pmd_t pmd) 198 { 199 return __va(pmd_val(pmd) & PAGE_MASK); 200 } 201 202 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd))) 203 204 /* we don't need complex calculations here as the pmd is folded into the pgd */ 205 #define pmd_addr_end(addr,end) (end) 206 207 208 #ifndef CONFIG_HIGHPTE 209 #define __pte_map(pmd) pmd_page_vaddr(*(pmd)) 210 #define __pte_unmap(pte) do { } while (0) 211 #else 212 #define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd))) 213 #define __pte_unmap(pte) kunmap_atomic(pte) 214 #endif 215 216 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) 217 218 #define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr)) 219 220 #define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr)) 221 #define pte_unmap(pte) __pte_unmap(pte) 222 223 #define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT) 224 #define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot)) 225 226 #define pte_page(pte) pfn_to_page(pte_pfn(pte)) 227 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot) 228 229 #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext) 230 #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0) 231 232 #if __LINUX_ARM_ARCH__ < 6 233 static inline void __sync_icache_dcache(pte_t pteval) 234 { 235 } 236 #else 237 extern void __sync_icache_dcache(pte_t pteval); 238 #endif 239 240 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 241 pte_t *ptep, pte_t pteval) 242 { 243 if (addr >= TASK_SIZE) 244 set_pte_ext(ptep, pteval, 0); 245 else { 246 __sync_icache_dcache(pteval); 247 set_pte_ext(ptep, pteval, PTE_EXT_NG); 248 } 249 } 250 251 #define pte_none(pte) (!pte_val(pte)) 252 #define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT) 253 #define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY)) 254 #define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY) 255 #define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG) 256 #define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN)) 257 #define pte_special(pte) (0) 258 259 #define pte_present_user(pte) \ 260 ((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \ 261 (L_PTE_PRESENT | L_PTE_USER)) 262 263 #define PTE_BIT_FUNC(fn,op) \ 264 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; } 265 266 PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY); 267 PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY); 268 PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY); 269 PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY); 270 PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG); 271 PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG); 272 273 static inline pte_t pte_mkspecial(pte_t pte) { return pte; } 274 275 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 276 { 277 const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER; 278 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 279 return pte; 280 } 281 282 /* 283 * Encode and decode a swap entry. Swap entries are stored in the Linux 284 * page tables as follows: 285 * 286 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 287 * 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 0 288 * <--------------- offset --------------------> <- type --> 0 0 0 289 * 290 * This gives us up to 63 swap files and 32GB per swap file. Note that 291 * the offset field is always non-zero. 292 */ 293 #define __SWP_TYPE_SHIFT 3 294 #define __SWP_TYPE_BITS 6 295 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1) 296 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT) 297 298 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK) 299 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT) 300 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) }) 301 302 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 303 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 304 305 /* 306 * It is an error for the kernel to have more swap files than we can 307 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES 308 * is increased beyond what we presently support. 309 */ 310 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS) 311 312 /* 313 * Encode and decode a file entry. File entries are stored in the Linux 314 * page tables as follows: 315 * 316 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 317 * 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 0 318 * <----------------------- offset ------------------------> 1 0 0 319 */ 320 #define pte_file(pte) (pte_val(pte) & L_PTE_FILE) 321 #define pte_to_pgoff(x) (pte_val(x) >> 3) 322 #define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE) 323 324 #define PTE_FILE_MAX_BITS 29 325 326 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */ 327 /* FIXME: this is not correct */ 328 #define kern_addr_valid(addr) (1) 329 330 #include <asm-generic/pgtable.h> 331 332 /* 333 * We provide our own arch_get_unmapped_area to cope with VIPT caches. 334 */ 335 #define HAVE_ARCH_UNMAPPED_AREA 336 337 /* 338 * remap a physical page `pfn' of size `size' with page protection `prot' 339 * into virtual address `from' 340 */ 341 #define io_remap_pfn_range(vma,from,pfn,size,prot) \ 342 remap_pfn_range(vma, from, pfn, size, prot) 343 344 #define pgtable_cache_init() do { } while (0) 345 346 void identity_mapping_add(pgd_t *, unsigned long, unsigned long); 347 void identity_mapping_del(pgd_t *, unsigned long, unsigned long); 348 349 #endif /* !__ASSEMBLY__ */ 350 351 #endif /* CONFIG_MMU */ 352 353 #endif /* _ASMARM_PGTABLE_H */ 354