arch/arm64/include/asm/pgtable.h

   1 /*
   2  * Copyright (C) 2012 ARM Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16 #ifndef __ASM_PGTABLE_H
  17 #define __ASM_PGTABLE_H
  18
  19 #include <asm/proc-fns.h>
  20
  21 #include <asm/memory.h>
  22 #include <asm/pgtable-hwdef.h>
  23
  24 /*
  25  * Software defined PTE bits definition.
  26  */
  27 #define PTE_VALID               (_AT(pteval_t, 1) << 0)
  28 #define PTE_FILE                (_AT(pteval_t, 1) << 2) /* only when !pte_present() */
  29 #define PTE_DIRTY               (_AT(pteval_t, 1) << 55)
  30 #define PTE_SPECIAL             (_AT(pteval_t, 1) << 56)
  31 #define PTE_WRITE               (_AT(pteval_t, 1) << 57)
  32 #define PTE_PROT_NONE           (_AT(pteval_t, 1) << 58) /* only when !PTE_VALID */
  33
  34 /*
  35  * VMALLOC and SPARSEMEM_VMEMMAP ranges.
  36  *
  37  * VMEMAP_SIZE: allows the whole VA space to be covered by a struct page array
  38  *      (rounded up to PUD_SIZE).
  39  * VMALLOC_START: beginning of the kernel VA space
  40  * VMALLOC_END: extends to the available space below vmmemmap, PCI I/O space,
  41  *      fixed mappings and modules
  42  */
  43 #define VMEMMAP_SIZE            ALIGN((1UL << (VA_BITS - PAGE_SHIFT)) * sizeof(struct page), PUD_SIZE)
  44 #define VMALLOC_START           (UL(0xffffffffffffffff) << VA_BITS)
  45 #define VMALLOC_END             (PAGE_OFFSET - PUD_SIZE - VMEMMAP_SIZE - SZ_64K)
  46
  47 #define vmemmap                 ((struct page *)(VMALLOC_END + SZ_64K))
  48
  49 #define FIRST_USER_ADDRESS      0
  50
  51 #ifndef __ASSEMBLY__
  52 extern void __pte_error(const char *file, int line, unsigned long val);
  53 extern void __pmd_error(const char *file, int line, unsigned long val);
  54 extern void __pud_error(const char *file, int line, unsigned long val);
  55 extern void __pgd_error(const char *file, int line, unsigned long val);
  56
  57 #define pte_ERROR(pte)          __pte_error(__FILE__, __LINE__, pte_val(pte))
  58 #if CONFIG_ARM64_PGTABLE_LEVELS > 2
  59 #define pmd_ERROR(pmd)          __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
  60 #endif
  61 #if CONFIG_ARM64_PGTABLE_LEVELS > 3
  62 #define pud_ERROR(pud)          __pud_error(__FILE__, __LINE__, pud_val(pud))
  63 #endif
  64 #define pgd_ERROR(pgd)          __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
  65
  66 #ifdef CONFIG_SMP
  67 #define PROT_DEFAULT            (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
  68 #define PROT_SECT_DEFAULT       (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S)
  69 #else
  70 #define PROT_DEFAULT            (PTE_TYPE_PAGE | PTE_AF)
  71 #define PROT_SECT_DEFAULT       (PMD_TYPE_SECT | PMD_SECT_AF)
  72 #endif
  73
  74 #define PROT_DEVICE_nGnRE       (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_DEVICE_nGnRE))
  75 #define PROT_NORMAL_NC          (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_NORMAL_NC))
  76 #define PROT_NORMAL             (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_ATTRINDX(MT_NORMAL))
  77
  78 #define PROT_SECT_DEVICE_nGnRE  (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE))
  79 #define PROT_SECT_NORMAL        (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
  80 #define PROT_SECT_NORMAL_EXEC   (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL))
  81
  82 #define _PAGE_DEFAULT           (PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL))
  83
  84 #define PAGE_KERNEL             __pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_WRITE)
  85 #define PAGE_KERNEL_EXEC        __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE)
  86
  87 #define PAGE_HYP                __pgprot(_PAGE_DEFAULT | PTE_HYP)
  88 #define PAGE_HYP_DEVICE         __pgprot(PROT_DEVICE_nGnRE | PTE_HYP)
  89
  90 #define PAGE_S2                 __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_NORMAL) | PTE_S2_RDONLY)
  91 #define PAGE_S2_DEVICE          __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_DEVICE_nGnRE) | PTE_S2_RDWR | PTE_UXN)
  92
  93 #define PAGE_NONE               __pgprot(((_PAGE_DEFAULT) & ~PTE_TYPE_MASK) | PTE_PROT_NONE | PTE_PXN | PTE_UXN)
  94 #define PAGE_SHARED             __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
  95 #define PAGE_SHARED_EXEC        __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_WRITE)
  96 #define PAGE_COPY               __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
  97 #define PAGE_COPY_EXEC          __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN)
  98 #define PAGE_READONLY           __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
  99 #define PAGE_READONLY_EXEC      __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN)
 100
 101 #define __P000  PAGE_NONE
 102 #define __P001  PAGE_READONLY
 103 #define __P010  PAGE_COPY
 104 #define __P011  PAGE_COPY
 105 #define __P100  PAGE_READONLY_EXEC
 106 #define __P101  PAGE_READONLY_EXEC
 107 #define __P110  PAGE_COPY_EXEC
 108 #define __P111  PAGE_COPY_EXEC
 109
 110 #define __S000  PAGE_NONE
 111 #define __S001  PAGE_READONLY
 112 #define __S010  PAGE_SHARED
 113 #define __S011  PAGE_SHARED
 114 #define __S100  PAGE_READONLY_EXEC
 115 #define __S101  PAGE_READONLY_EXEC
 116 #define __S110  PAGE_SHARED_EXEC
 117 #define __S111  PAGE_SHARED_EXEC
 118
 119 /*
 120  * ZERO_PAGE is a global shared page that is always zero: used
 121  * for zero-mapped memory areas etc..
 122  */
 123 extern struct page *empty_zero_page;
 124 #define ZERO_PAGE(vaddr)        (empty_zero_page)
 125
 126 #define pte_pfn(pte)            ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
 127
 128 #define pfn_pte(pfn,prot)       (__pte(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
 129
 130 #define pte_none(pte)           (!pte_val(pte))
 131 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0))
 132 #define pte_page(pte)           (pfn_to_page(pte_pfn(pte)))
 133 #define pte_offset_kernel(dir,addr)     (pmd_page_vaddr(*(dir)) + pte_index(addr))
 134
 135 #define pte_offset_map(dir,addr)        pte_offset_kernel((dir), (addr))
 136 #define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
 137 #define pte_unmap(pte)                  do { } while (0)
 138 #define pte_unmap_nested(pte)           do { } while (0)
 139
 140 /*
 141  * The following only work if pte_present(). Undefined behaviour otherwise.
 142  */
 143 #define pte_present(pte)        (!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
 144 #define pte_dirty(pte)          (!!(pte_val(pte) & PTE_DIRTY))
 145 #define pte_young(pte)          (!!(pte_val(pte) & PTE_AF))
 146 #define pte_special(pte)        (!!(pte_val(pte) & PTE_SPECIAL))
 147 #define pte_write(pte)          (!!(pte_val(pte) & PTE_WRITE))
 148 #define pte_exec(pte)           (!(pte_val(pte) & PTE_UXN))
 149
 150 #define pte_valid_user(pte) \
 151         ((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER))
 152
 153 static inline pte_t pte_wrprotect(pte_t pte)
 154 {
 155         pte_val(pte) &= ~PTE_WRITE;
 156         return pte;
 157 }
 158
 159 static inline pte_t pte_mkwrite(pte_t pte)
 160 {
 161         pte_val(pte) |= PTE_WRITE;
 162         return pte;
 163 }
 164
 165 static inline pte_t pte_mkclean(pte_t pte)
 166 {
 167         pte_val(pte) &= ~PTE_DIRTY;
 168         return pte;
 169 }
 170
 171 static inline pte_t pte_mkdirty(pte_t pte)
 172 {
 173         pte_val(pte) |= PTE_DIRTY;
 174         return pte;
 175 }
 176
 177 static inline pte_t pte_mkold(pte_t pte)
 178 {
 179         pte_val(pte) &= ~PTE_AF;
 180         return pte;
 181 }
 182
 183 static inline pte_t pte_mkyoung(pte_t pte)
 184 {
 185         pte_val(pte) |= PTE_AF;
 186         return pte;
 187 }
 188
 189 static inline pte_t pte_mkspecial(pte_t pte)
 190 {
 191         pte_val(pte) |= PTE_SPECIAL;
 192         return pte;
 193 }
 194
 195 static inline void set_pte(pte_t *ptep, pte_t pte)
 196 {
 197         *ptep = pte;
 198 }
 199
 200 extern void __sync_icache_dcache(pte_t pteval, unsigned long addr);
 201
 202 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 203                               pte_t *ptep, pte_t pte)
 204 {
 205         if (pte_valid_user(pte)) {
 206                 if (!pte_special(pte) && pte_exec(pte))
 207                         __sync_icache_dcache(pte, addr);
 208                 if (pte_dirty(pte) && pte_write(pte))
 209                         pte_val(pte) &= ~PTE_RDONLY;
 210                 else
 211                         pte_val(pte) |= PTE_RDONLY;
 212         }
 213
 214         set_pte(ptep, pte);
 215 }
 216
 217 /*
 218  * Huge pte definitions.
 219  */
 220 #define pte_huge(pte)           (!(pte_val(pte) & PTE_TABLE_BIT))
 221 #define pte_mkhuge(pte)         (__pte(pte_val(pte) & ~PTE_TABLE_BIT))
 222
 223 /*
 224  * Hugetlb definitions.
 225  */
 226 #define HUGE_MAX_HSTATE         2
 227 #define HPAGE_SHIFT             PMD_SHIFT
 228 #define HPAGE_SIZE              (_AC(1, UL) << HPAGE_SHIFT)
 229 #define HPAGE_MASK              (~(HPAGE_SIZE - 1))
 230 #define HUGETLB_PAGE_ORDER      (HPAGE_SHIFT - PAGE_SHIFT)
 231
 232 #define __HAVE_ARCH_PTE_SPECIAL
 233
 234 static inline pte_t pmd_pte(pmd_t pmd)
 235 {
 236         return __pte(pmd_val(pmd));
 237 }
 238
 239 static inline pmd_t pte_pmd(pte_t pte)
 240 {
 241         return __pmd(pte_val(pte));
 242 }
 243
 244 /*
 245  * THP definitions.
 246  */
 247
 248 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 249 #define pmd_trans_huge(pmd)     (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))
 250 #define pmd_trans_splitting(pmd)        pte_special(pmd_pte(pmd))
 251 #endif
 252
 253 #define pmd_young(pmd)          pte_young(pmd_pte(pmd))
 254 #define pmd_wrprotect(pmd)      pte_pmd(pte_wrprotect(pmd_pte(pmd)))
 255 #define pmd_mksplitting(pmd)    pte_pmd(pte_mkspecial(pmd_pte(pmd)))
 256 #define pmd_mkold(pmd)          pte_pmd(pte_mkold(pmd_pte(pmd)))
 257 #define pmd_mkwrite(pmd)        pte_pmd(pte_mkwrite(pmd_pte(pmd)))
 258 #define pmd_mkdirty(pmd)        pte_pmd(pte_mkdirty(pmd_pte(pmd)))
 259 #define pmd_mkyoung(pmd)        pte_pmd(pte_mkyoung(pmd_pte(pmd)))
 260 #define pmd_mknotpresent(pmd)   (__pmd(pmd_val(pmd) & ~PMD_TYPE_MASK))
 261
 262 #define __HAVE_ARCH_PMD_WRITE
 263 #define pmd_write(pmd)          pte_write(pmd_pte(pmd))
 264
 265 #define pmd_mkhuge(pmd)         (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
 266
 267 #define pmd_pfn(pmd)            (((pmd_val(pmd) & PMD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
 268 #define pfn_pmd(pfn,prot)       (__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
 269 #define mk_pmd(page,prot)       pfn_pmd(page_to_pfn(page),prot)
 270
 271 #define pmd_page(pmd)           pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
 272 #define pud_pfn(pud)            (((pud_val(pud) & PUD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
 273
 274 #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
 275
 276 static inline int has_transparent_hugepage(void)
 277 {
 278         return 1;
 279 }
 280
 281 #define __pgprot_modify(prot,mask,bits) \
 282         __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
 283
 284 /*
 285  * Mark the prot value as uncacheable and unbufferable.
 286  */
 287 #define pgprot_noncached(prot) \
 288         __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
 289 #define pgprot_writecombine(prot) \
 290         __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
 291 #define __HAVE_PHYS_MEM_ACCESS_PROT
 292 struct file;
 293 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 294                                      unsigned long size, pgprot_t vma_prot);
 295
 296 #define pmd_none(pmd)           (!pmd_val(pmd))
 297 #define pmd_present(pmd)        (pmd_val(pmd))
 298
 299 #define pmd_bad(pmd)            (!(pmd_val(pmd) & 2))
 300
 301 #define pmd_table(pmd)          ((pmd_val(pmd) & PMD_TYPE_MASK) == \
 302                                  PMD_TYPE_TABLE)
 303 #define pmd_sect(pmd)           ((pmd_val(pmd) & PMD_TYPE_MASK) == \
 304                                  PMD_TYPE_SECT)
 305
 306 #ifdef CONFIG_ARM64_64K_PAGES
 307 #define pud_sect(pud)           (0)
 308 #else
 309 #define pud_sect(pud)           ((pud_val(pud) & PUD_TYPE_MASK) == \
 310                                  PUD_TYPE_SECT)
 311 #endif
 312
 313 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 314 {
 315         *pmdp = pmd;
 316         dsb(ishst);
 317 }
 318
 319 static inline void pmd_clear(pmd_t *pmdp)
 320 {
 321         set_pmd(pmdp, __pmd(0));
 322 }
 323
 324 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
 325 {
 326         return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
 327 }
 328
 329 #define pmd_page(pmd)           pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
 330
 331 /*
 332  * Conversion functions: convert a page and protection to a page entry,
 333  * and a page entry and page directory to the page they refer to.
 334  */
 335 #define mk_pte(page,prot)       pfn_pte(page_to_pfn(page),prot)
 336
 337 #if CONFIG_ARM64_PGTABLE_LEVELS > 2
 338
 339 #define pud_none(pud)           (!pud_val(pud))
 340 #define pud_bad(pud)            (!(pud_val(pud) & 2))
 341 #define pud_present(pud)        (pud_val(pud))
 342
 343 static inline void set_pud(pud_t *pudp, pud_t pud)
 344 {
 345         *pudp = pud;
 346         dsb(ishst);
 347 }
 348
 349 static inline void pud_clear(pud_t *pudp)
 350 {
 351         set_pud(pudp, __pud(0));
 352 }
 353
 354 static inline pmd_t *pud_page_vaddr(pud_t pud)
 355 {
 356         return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK);
 357 }
 358
 359 #endif  /* CONFIG_ARM64_PGTABLE_LEVELS > 2 */
 360
 361 #if CONFIG_ARM64_PGTABLE_LEVELS > 3
 362
 363 #define pgd_none(pgd)           (!pgd_val(pgd))
 364 #define pgd_bad(pgd)            (!(pgd_val(pgd) & 2))
 365 #define pgd_present(pgd)        (pgd_val(pgd))
 366
 367 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
 368 {
 369         *pgdp = pgd;
 370         dsb(ishst);
 371 }
 372
 373 static inline void pgd_clear(pgd_t *pgdp)
 374 {
 375         set_pgd(pgdp, __pgd(0));
 376 }
 377
 378 static inline pud_t *pgd_page_vaddr(pgd_t pgd)
 379 {
 380         return __va(pgd_val(pgd) & PHYS_MASK & (s32)PAGE_MASK);
 381 }
 382
 383 #endif  /* CONFIG_ARM64_PGTABLE_LEVELS > 3 */
 384
 385 /* to find an entry in a page-table-directory */
 386 #define pgd_index(addr)         (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
 387
 388 #define pgd_offset(mm, addr)    ((mm)->pgd+pgd_index(addr))
 389
 390 /* to find an entry in a kernel page-table-directory */
 391 #define pgd_offset_k(addr)      pgd_offset(&init_mm, addr)
 392
 393 #if CONFIG_ARM64_PGTABLE_LEVELS > 3
 394 #define pud_index(addr)         (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
 395 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long addr)
 396 {
 397         return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(addr);
 398 }
 399 #endif
 400
 401 /* Find an entry in the second-level page table.. */
 402 #if CONFIG_ARM64_PGTABLE_LEVELS > 2
 403 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
 404 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
 405 {
 406         return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
 407 }
 408 #endif
 409
 410 /* Find an entry in the third-level page table.. */
 411 #define pte_index(addr)         (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 412
 413 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 414 {
 415         const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
 416                               PTE_PROT_NONE | PTE_VALID | PTE_WRITE;
 417         pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
 418         return pte;
 419 }
 420
 421 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 422 {
 423         return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
 424 }
 425
 426 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
 427 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
 428
 429 /*
 430  * Encode and decode a swap entry:
 431  *      bits 0-1:       present (must be zero)
 432  *      bit  2:         PTE_FILE
 433  *      bits 3-8:       swap type
 434  *      bits 9-57:      swap offset
 435  */
 436 #define __SWP_TYPE_SHIFT        3
 437 #define __SWP_TYPE_BITS         6
 438 #define __SWP_OFFSET_BITS       49
 439 #define __SWP_TYPE_MASK         ((1 << __SWP_TYPE_BITS) - 1)
 440 #define __SWP_OFFSET_SHIFT      (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
 441 #define __SWP_OFFSET_MASK       ((1UL << __SWP_OFFSET_BITS) - 1)
 442
 443 #define __swp_type(x)           (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
 444 #define __swp_offset(x)         (((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
 445 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
 446
 447 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
 448 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
 449
 450 /*
 451  * Ensure that there are not more swap files than can be encoded in the kernel
 452  * PTEs.
 453  */
 454 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
 455
 456 /*
 457  * Encode and decode a file entry:
 458  *      bits 0-1:       present (must be zero)
 459  *      bit  2:         PTE_FILE
 460  *      bits 3-57:      file offset / PAGE_SIZE
 461  */
 462 #define pte_file(pte)           (pte_val(pte) & PTE_FILE)
 463 #define pte_to_pgoff(x)         (pte_val(x) >> 3)
 464 #define pgoff_to_pte(x)         __pte(((x) << 3) | PTE_FILE)
 465
 466 #define PTE_FILE_MAX_BITS       55
 467
 468 extern int kern_addr_valid(unsigned long addr);
 469
 470 #include <asm-generic/pgtable.h>
 471
 472 #define pgtable_cache_init() do { } while (0)
 473
 474 #endif /* !__ASSEMBLY__ */
 475
 476 #endif /* __ASM_PGTABLE_H */