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 #define pgprot_stronglyordered(prot) \ 105 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED) 106 107 #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE 108 #define pgprot_dmacoherent(prot) \ 109 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN) 110 #define __HAVE_PHYS_MEM_ACCESS_PROT 111 struct file; 112 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 113 unsigned long size, pgprot_t vma_prot); 114 #else 115 #define pgprot_dmacoherent(prot) \ 116 __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN) 117 #endif 118 119 #endif /* __ASSEMBLY__ */ 120 121 /* 122 * The table below defines the page protection levels that we insert into our 123 * Linux page table version. These get translated into the best that the 124 * architecture can perform. Note that on most ARM hardware: 125 * 1) We cannot do execute protection 126 * 2) If we could do execute protection, then read is implied 127 * 3) write implies read permissions 128 */ 129 #define __P000 __PAGE_NONE 130 #define __P001 __PAGE_READONLY 131 #define __P010 __PAGE_COPY 132 #define __P011 __PAGE_COPY 133 #define __P100 __PAGE_READONLY_EXEC 134 #define __P101 __PAGE_READONLY_EXEC 135 #define __P110 __PAGE_COPY_EXEC 136 #define __P111 __PAGE_COPY_EXEC 137 138 #define __S000 __PAGE_NONE 139 #define __S001 __PAGE_READONLY 140 #define __S010 __PAGE_SHARED 141 #define __S011 __PAGE_SHARED 142 #define __S100 __PAGE_READONLY_EXEC 143 #define __S101 __PAGE_READONLY_EXEC 144 #define __S110 __PAGE_SHARED_EXEC 145 #define __S111 __PAGE_SHARED_EXEC 146 147 #ifndef __ASSEMBLY__ 148 /* 149 * ZERO_PAGE is a global shared page that is always zero: used 150 * for zero-mapped memory areas etc.. 151 */ 152 extern struct page *empty_zero_page; 153 #define ZERO_PAGE(vaddr) (empty_zero_page) 154 155 156 extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; 157 158 /* to find an entry in a page-table-directory */ 159 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT) 160 161 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr)) 162 163 /* to find an entry in a kernel page-table-directory */ 164 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) 165 166 /* 167 * The "pgd_xxx()" functions here are trivial for a folded two-level 168 * setup: the pgd is never bad, and a pmd always exists (as it's folded 169 * into the pgd entry) 170 */ 171 #define pgd_none(pgd) (0) 172 #define pgd_bad(pgd) (0) 173 #define pgd_present(pgd) (1) 174 #define pgd_clear(pgdp) do { } while (0) 175 #define set_pgd(pgd,pgdp) do { } while (0) 176 #define set_pud(pud,pudp) do { } while (0) 177 178 179 /* Find an entry in the second-level page table.. */ 180 #define pmd_offset(dir, addr) ((pmd_t *)(dir)) 181 182 #define pmd_none(pmd) (!pmd_val(pmd)) 183 #define pmd_present(pmd) (pmd_val(pmd)) 184 #define pmd_bad(pmd) (pmd_val(pmd) & 2) 185 186 #define copy_pmd(pmdpd,pmdps) \ 187 do { \ 188 pmdpd[0] = pmdps[0]; \ 189 pmdpd[1] = pmdps[1]; \ 190 flush_pmd_entry(pmdpd); \ 191 } while (0) 192 193 #define pmd_clear(pmdp) \ 194 do { \ 195 pmdp[0] = __pmd(0); \ 196 pmdp[1] = __pmd(0); \ 197 clean_pmd_entry(pmdp); \ 198 } while (0) 199 200 static inline pte_t *pmd_page_vaddr(pmd_t pmd) 201 { 202 return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK); 203 } 204 205 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK)) 206 207 /* we don't need complex calculations here as the pmd is folded into the pgd */ 208 #define pmd_addr_end(addr,end) (end) 209 210 211 #ifndef CONFIG_HIGHPTE 212 #define __pte_map(pmd) pmd_page_vaddr(*(pmd)) 213 #define __pte_unmap(pte) do { } while (0) 214 #else 215 #define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd))) 216 #define __pte_unmap(pte) kunmap_atomic(pte) 217 #endif 218 219 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) 220 221 #define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr)) 222 223 #define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr)) 224 #define pte_unmap(pte) __pte_unmap(pte) 225 226 #define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT) 227 #define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot)) 228 229 #define pte_page(pte) pfn_to_page(pte_pfn(pte)) 230 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot) 231 232 #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext) 233 #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0) 234 235 #if __LINUX_ARM_ARCH__ < 6 236 static inline void __sync_icache_dcache(pte_t pteval) 237 { 238 } 239 #else 240 extern void __sync_icache_dcache(pte_t pteval); 241 #endif 242 243 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 244 pte_t *ptep, pte_t pteval) 245 { 246 if (addr >= TASK_SIZE) 247 set_pte_ext(ptep, pteval, 0); 248 else { 249 __sync_icache_dcache(pteval); 250 set_pte_ext(ptep, pteval, PTE_EXT_NG); 251 } 252 } 253 254 #define pte_none(pte) (!pte_val(pte)) 255 #define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT) 256 #define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY)) 257 #define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY) 258 #define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG) 259 #define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN)) 260 #define pte_special(pte) (0) 261 262 #define pte_present_user(pte) \ 263 ((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \ 264 (L_PTE_PRESENT | L_PTE_USER)) 265 266 #define PTE_BIT_FUNC(fn,op) \ 267 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; } 268 269 PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY); 270 PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY); 271 PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY); 272 PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY); 273 PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG); 274 PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG); 275 276 static inline pte_t pte_mkspecial(pte_t pte) { return pte; } 277 278 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) 279 { 280 const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER; 281 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); 282 return pte; 283 } 284 285 /* 286 * Encode and decode a swap entry. Swap entries are stored in the Linux 287 * page tables as follows: 288 * 289 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 290 * 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 0 291 * <--------------- offset --------------------> <- type --> 0 0 0 292 * 293 * This gives us up to 63 swap files and 32GB per swap file. Note that 294 * the offset field is always non-zero. 295 */ 296 #define __SWP_TYPE_SHIFT 3 297 #define __SWP_TYPE_BITS 6 298 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1) 299 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT) 300 301 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK) 302 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT) 303 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) }) 304 305 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 306 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) 307 308 /* 309 * It is an error for the kernel to have more swap files than we can 310 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES 311 * is increased beyond what we presently support. 312 */ 313 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS) 314 315 /* 316 * Encode and decode a file entry. File entries are stored in the Linux 317 * page tables as follows: 318 * 319 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 320 * 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 0 321 * <----------------------- offset ------------------------> 1 0 0 322 */ 323 #define pte_file(pte) (pte_val(pte) & L_PTE_FILE) 324 #define pte_to_pgoff(x) (pte_val(x) >> 3) 325 #define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE) 326 327 #define PTE_FILE_MAX_BITS 29 328 329 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */ 330 /* FIXME: this is not correct */ 331 #define kern_addr_valid(addr) (1) 332 333 #include <asm-generic/pgtable.h> 334 335 /* 336 * We provide our own arch_get_unmapped_area to cope with VIPT caches. 337 */ 338 #define HAVE_ARCH_UNMAPPED_AREA 339 340 /* 341 * remap a physical page `pfn' of size `size' with page protection `prot' 342 * into virtual address `from' 343 */ 344 #define io_remap_pfn_range(vma,from,pfn,size,prot) \ 345 remap_pfn_range(vma, from, pfn, size, prot) 346 347 #define pgtable_cache_init() do { } while (0) 348 349 void identity_mapping_add(pgd_t *, unsigned long, unsigned long); 350 void identity_mapping_del(pgd_t *, unsigned long, unsigned long); 351 352 #endif /* !__ASSEMBLY__ */ 353 354 #endif /* CONFIG_MMU */ 355 356 #endif /* _ASMARM_PGTABLE_H */ 357