arch/mips/include/asm/pgtable.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2003 Ralf Baechle
   7  */
   8 #ifndef _ASM_PGTABLE_H
   9 #define _ASM_PGTABLE_H
  10
  11 #include <linux/mm_types.h>
  12 #include <linux/mmzone.h>
  13 #ifdef CONFIG_32BIT
  14 #include <asm/pgtable-32.h>
  15 #endif
  16 #ifdef CONFIG_64BIT
  17 #include <asm/pgtable-64.h>
  18 #endif
  19
  20 #include <asm/io.h>
  21 #include <asm/pgtable-bits.h>
  22
  23 struct mm_struct;
  24 struct vm_area_struct;
  25
  26 #define PAGE_NONE       __pgprot(_PAGE_PRESENT | _CACHE_CACHABLE_NONCOHERENT)
  27 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | \
  28                                  _page_cachable_default)
  29 #define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_NO_EXEC | \
  30                                  _page_cachable_default)
  31 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_READ | \
  32                                  _page_cachable_default)
  33 #define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
  34                                  _PAGE_GLOBAL | _page_cachable_default)
  35 #define PAGE_KERNEL_NC  __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
  36                                  _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT)
  37 #define PAGE_USERIO     __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
  38                                  _page_cachable_default)
  39 #define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
  40                         __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
  41
  42 /*
  43  * If _PAGE_NO_EXEC is not defined, we can't do page protection for
  44  * execute, and consider it to be the same as read. Also, write
  45  * permissions imply read permissions. This is the closest we can get
  46  * by reasonable means..
  47  */
  48
  49 /*
  50  * Dummy values to fill the table in mmap.c
  51  * The real values will be generated at runtime
  52  */
  53 #define __P000 __pgprot(0)
  54 #define __P001 __pgprot(0)
  55 #define __P010 __pgprot(0)
  56 #define __P011 __pgprot(0)
  57 #define __P100 __pgprot(0)
  58 #define __P101 __pgprot(0)
  59 #define __P110 __pgprot(0)
  60 #define __P111 __pgprot(0)
  61
  62 #define __S000 __pgprot(0)
  63 #define __S001 __pgprot(0)
  64 #define __S010 __pgprot(0)
  65 #define __S011 __pgprot(0)
  66 #define __S100 __pgprot(0)
  67 #define __S101 __pgprot(0)
  68 #define __S110 __pgprot(0)
  69 #define __S111 __pgprot(0)
  70
  71 extern unsigned long _page_cachable_default;
  72
  73 /*
  74  * ZERO_PAGE is a global shared page that is always zero; used
  75  * for zero-mapped memory areas etc..
  76  */
  77
  78 extern unsigned long empty_zero_page;
  79 extern unsigned long zero_page_mask;
  80
  81 #define ZERO_PAGE(vaddr) \
  82         (virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
  83 #define __HAVE_COLOR_ZERO_PAGE
  84
  85 extern void paging_init(void);
  86
  87 /*
  88  * Conversion functions: convert a page and protection to a page entry,
  89  * and a page entry and page directory to the page they refer to.
  90  */
  91 #define pmd_phys(pmd)           virt_to_phys((void *)pmd_val(pmd))
  92
  93 #define __pmd_page(pmd)         (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
  94 #ifndef CONFIG_TRANSPARENT_HUGEPAGE
  95 #define pmd_page(pmd)           __pmd_page(pmd)
  96 #endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
  97
  98 #define pmd_page_vaddr(pmd)     pmd_val(pmd)
  99
 100 #define htw_stop()                                                      \
 101 do {                                                                    \
 102         unsigned long flags;                                            \
 103                                                                         \
 104         if (cpu_has_htw) {                                              \
 105                 local_irq_save(flags);                                  \
 106                 if(!raw_current_cpu_data.htw_seq++) {                   \
 107                         write_c0_pwctl(read_c0_pwctl() &                \
 108                                        ~(1 << MIPS_PWCTL_PWEN_SHIFT));  \
 109                         back_to_back_c0_hazard();                       \
 110                 }                                                       \
 111                 local_irq_restore(flags);                               \
 112         }                                                               \
 113 } while(0)
 114
 115 #define htw_start()                                                     \
 116 do {                                                                    \
 117         unsigned long flags;                                            \
 118                                                                         \
 119         if (cpu_has_htw) {                                              \
 120                 local_irq_save(flags);                                  \
 121                 if (!--raw_current_cpu_data.htw_seq) {                  \
 122                         write_c0_pwctl(read_c0_pwctl() |                \
 123                                        (1 << MIPS_PWCTL_PWEN_SHIFT));   \
 124                         back_to_back_c0_hazard();                       \
 125                 }                                                       \
 126                 local_irq_restore(flags);                               \
 127         }                                                               \
 128 } while(0)
 129
 130 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 131
 132 #define pte_none(pte)           (!(((pte).pte_high) & ~_PAGE_GLOBAL))
 133 #define pte_present(pte)        ((pte).pte_low & _PAGE_PRESENT)
 134
 135 static inline void set_pte(pte_t *ptep, pte_t pte)
 136 {
 137         ptep->pte_high = pte.pte_high;
 138         smp_wmb();
 139         ptep->pte_low = pte.pte_low;
 140
 141         if (pte.pte_high & _PAGE_GLOBAL) {
 142                 pte_t *buddy = ptep_buddy(ptep);
 143                 /*
 144                  * Make sure the buddy is global too (if it's !none,
 145                  * it better already be global)
 146                  */
 147                 if (pte_none(*buddy))
 148                         buddy->pte_high |= _PAGE_GLOBAL;
 149         }
 150 }
 151 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
 152
 153 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 154 {
 155         pte_t null = __pte(0);
 156
 157         htw_stop();
 158         /* Preserve global status for the pair */
 159         if (ptep_buddy(ptep)->pte_high & _PAGE_GLOBAL)
 160                 null.pte_high = _PAGE_GLOBAL;
 161
 162         set_pte_at(mm, addr, ptep, null);
 163         htw_start();
 164 }
 165 #else
 166
 167 #define pte_none(pte)           (!(pte_val(pte) & ~_PAGE_GLOBAL))
 168 #define pte_present(pte)        (pte_val(pte) & _PAGE_PRESENT)
 169
 170 /*
 171  * Certain architectures need to do special things when pte's
 172  * within a page table are directly modified.  Thus, the following
 173  * hook is made available.
 174  */
 175 static inline void set_pte(pte_t *ptep, pte_t pteval)
 176 {
 177         *ptep = pteval;
 178 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
 179         if (pte_val(pteval) & _PAGE_GLOBAL) {
 180                 pte_t *buddy = ptep_buddy(ptep);
 181                 /*
 182                  * Make sure the buddy is global too (if it's !none,
 183                  * it better already be global)
 184                  */
 185 #ifdef CONFIG_SMP
 186                 /*
 187                  * For SMP, multiple CPUs can race, so we need to do
 188                  * this atomically.
 189                  */
 190 #ifdef CONFIG_64BIT
 191 #define LL_INSN "lld"
 192 #define SC_INSN "scd"
 193 #else /* CONFIG_32BIT */
 194 #define LL_INSN "ll"
 195 #define SC_INSN "sc"
 196 #endif
 197                 unsigned long page_global = _PAGE_GLOBAL;
 198                 unsigned long tmp;
 199
 200                 __asm__ __volatile__ (
 201                         "       .set    push\n"
 202                         "       .set    noreorder\n"
 203                         "1:     " LL_INSN "     %[tmp], %[buddy]\n"
 204                         "       bnez    %[tmp], 2f\n"
 205                         "        or     %[tmp], %[tmp], %[global]\n"
 206                         "       " SC_INSN "     %[tmp], %[buddy]\n"
 207                         "       beqz    %[tmp], 1b\n"
 208                         "        nop\n"
 209                         "2:\n"
 210                         "       .set pop"
 211                         : [buddy] "+m" (buddy->pte),
 212                           [tmp] "=&r" (tmp)
 213                         : [global] "r" (page_global));
 214 #else /* !CONFIG_SMP */
 215                 if (pte_none(*buddy))
 216                         pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
 217 #endif /* CONFIG_SMP */
 218         }
 219 #endif
 220 }
 221 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
 222
 223 static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 224 {
 225         htw_stop();
 226 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
 227         /* Preserve global status for the pair */
 228         if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
 229                 set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
 230         else
 231 #endif
 232                 set_pte_at(mm, addr, ptep, __pte(0));
 233         htw_start();
 234 }
 235 #endif
 236
 237 /*
 238  * (pmds are folded into puds so this doesn't get actually called,
 239  * but the define is needed for a generic inline function.)
 240  */
 241 #define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)
 242
 243 #ifndef __PAGETABLE_PMD_FOLDED
 244 /*
 245  * (puds are folded into pgds so this doesn't get actually called,
 246  * but the define is needed for a generic inline function.)
 247  */
 248 #define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
 249 #endif
 250
 251 #define PGD_T_LOG2      (__builtin_ffs(sizeof(pgd_t)) - 1)
 252 #define PMD_T_LOG2      (__builtin_ffs(sizeof(pmd_t)) - 1)
 253 #define PTE_T_LOG2      (__builtin_ffs(sizeof(pte_t)) - 1)
 254
 255 /*
 256  * We used to declare this array with size but gcc 3.3 and older are not able
 257  * to find that this expression is a constant, so the size is dropped.
 258  */
 259 extern pgd_t swapper_pg_dir[];
 260
 261 /*
 262  * The following only work if pte_present() is true.
 263  * Undefined behaviour if not..
 264  */
 265 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 266 static inline int pte_write(pte_t pte)  { return pte.pte_low & _PAGE_WRITE; }
 267 static inline int pte_dirty(pte_t pte)  { return pte.pte_low & _PAGE_MODIFIED; }
 268 static inline int pte_young(pte_t pte)  { return pte.pte_low & _PAGE_ACCESSED; }
 269
 270 static inline pte_t pte_wrprotect(pte_t pte)
 271 {
 272         pte.pte_low  &= ~_PAGE_WRITE;
 273         pte.pte_high &= ~_PAGE_SILENT_WRITE;
 274         return pte;
 275 }
 276
 277 static inline pte_t pte_mkclean(pte_t pte)
 278 {
 279         pte.pte_low  &= ~_PAGE_MODIFIED;
 280         pte.pte_high &= ~_PAGE_SILENT_WRITE;
 281         return pte;
 282 }
 283
 284 static inline pte_t pte_mkold(pte_t pte)
 285 {
 286         pte.pte_low  &= ~_PAGE_ACCESSED;
 287         pte.pte_high &= ~_PAGE_SILENT_READ;
 288         return pte;
 289 }
 290
 291 static inline pte_t pte_mkwrite(pte_t pte)
 292 {
 293         pte.pte_low |= _PAGE_WRITE;
 294         if (pte.pte_low & _PAGE_MODIFIED)
 295                 pte.pte_high |= _PAGE_SILENT_WRITE;
 296         return pte;
 297 }
 298
 299 static inline pte_t pte_mkdirty(pte_t pte)
 300 {
 301         pte.pte_low |= _PAGE_MODIFIED;
 302         if (pte.pte_low & _PAGE_WRITE)
 303                 pte.pte_high |= _PAGE_SILENT_WRITE;
 304         return pte;
 305 }
 306
 307 static inline pte_t pte_mkyoung(pte_t pte)
 308 {
 309         pte.pte_low |= _PAGE_ACCESSED;
 310         if (pte.pte_low & _PAGE_READ)
 311                 pte.pte_high |= _PAGE_SILENT_READ;
 312         return pte;
 313 }
 314 #else
 315 static inline int pte_write(pte_t pte)  { return pte_val(pte) & _PAGE_WRITE; }
 316 static inline int pte_dirty(pte_t pte)  { return pte_val(pte) & _PAGE_MODIFIED; }
 317 static inline int pte_young(pte_t pte)  { return pte_val(pte) & _PAGE_ACCESSED; }
 318
 319 static inline pte_t pte_wrprotect(pte_t pte)
 320 {
 321         pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 322         return pte;
 323 }
 324
 325 static inline pte_t pte_mkclean(pte_t pte)
 326 {
 327         pte_val(pte) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
 328         return pte;
 329 }
 330
 331 static inline pte_t pte_mkold(pte_t pte)
 332 {
 333         pte_val(pte) &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
 334         return pte;
 335 }
 336
 337 static inline pte_t pte_mkwrite(pte_t pte)
 338 {
 339         pte_val(pte) |= _PAGE_WRITE;
 340         if (pte_val(pte) & _PAGE_MODIFIED)
 341                 pte_val(pte) |= _PAGE_SILENT_WRITE;
 342         return pte;
 343 }
 344
 345 static inline pte_t pte_mkdirty(pte_t pte)
 346 {
 347         pte_val(pte) |= _PAGE_MODIFIED;
 348         if (pte_val(pte) & _PAGE_WRITE)
 349                 pte_val(pte) |= _PAGE_SILENT_WRITE;
 350         return pte;
 351 }
 352
 353 static inline pte_t pte_mkyoung(pte_t pte)
 354 {
 355         pte_val(pte) |= _PAGE_ACCESSED;
 356 #ifdef CONFIG_CPU_MIPSR2
 357         if (!(pte_val(pte) & _PAGE_NO_READ))
 358                 pte_val(pte) |= _PAGE_SILENT_READ;
 359         else
 360 #endif
 361         if (pte_val(pte) & _PAGE_READ)
 362                 pte_val(pte) |= _PAGE_SILENT_READ;
 363         return pte;
 364 }
 365
 366 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
 367 static inline int pte_huge(pte_t pte)   { return pte_val(pte) & _PAGE_HUGE; }
 368
 369 static inline pte_t pte_mkhuge(pte_t pte)
 370 {
 371         pte_val(pte) |= _PAGE_HUGE;
 372         return pte;
 373 }
 374 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
 375 #endif
 376 static inline int pte_special(pte_t pte)        { return 0; }
 377 static inline pte_t pte_mkspecial(pte_t pte)    { return pte; }
 378
 379 /*
 380  * Macro to make mark a page protection value as "uncacheable".  Note
 381  * that "protection" is really a misnomer here as the protection value
 382  * contains the memory attribute bits, dirty bits, and various other
 383  * bits as well.
 384  */
 385 #define pgprot_noncached pgprot_noncached
 386
 387 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 388 {
 389         unsigned long prot = pgprot_val(_prot);
 390
 391         prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
 392
 393         return __pgprot(prot);
 394 }
 395
 396 #define pgprot_writecombine pgprot_writecombine
 397
 398 static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
 399 {
 400         unsigned long prot = pgprot_val(_prot);
 401
 402         /* cpu_data[0].writecombine is already shifted by _CACHE_SHIFT */
 403         prot = (prot & ~_CACHE_MASK) | cpu_data[0].writecombine;
 404
 405         return __pgprot(prot);
 406 }
 407
 408 /*
 409  * Conversion functions: convert a page and protection to a page entry,
 410  * and a page entry and page directory to the page they refer to.
 411  */
 412 #define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 413
 414 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 415 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 416 {
 417         pte.pte_low  &= (_PAGE_MODIFIED | _PAGE_ACCESSED | _PFNX_MASK);
 418         pte.pte_high &= (_PFN_MASK | _CACHE_MASK);
 419         pte.pte_low  |= pgprot_val(newprot) & ~_PFNX_MASK;
 420         pte.pte_high |= pgprot_val(newprot) & ~_PFN_MASK;
 421         return pte;
 422 }
 423 #else
 424 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 425 {
 426         return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
 427 }
 428 #endif
 429
 430
 431 extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
 432         pte_t pte);
 433 extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
 434         pte_t pte);
 435
 436 static inline void update_mmu_cache(struct vm_area_struct *vma,
 437         unsigned long address, pte_t *ptep)
 438 {
 439         pte_t pte = *ptep;
 440         __update_tlb(vma, address, pte);
 441         __update_cache(vma, address, pte);
 442 }
 443
 444 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
 445         unsigned long address, pmd_t *pmdp)
 446 {
 447         pte_t pte = *(pte_t *)pmdp;
 448
 449         __update_tlb(vma, address, pte);
 450 }
 451
 452 #define kern_addr_valid(addr)   (1)
 453
 454 #ifdef CONFIG_PHYS_ADDR_T_64BIT
 455 extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);
 456
 457 static inline int io_remap_pfn_range(struct vm_area_struct *vma,
 458                 unsigned long vaddr,
 459                 unsigned long pfn,
 460                 unsigned long size,
 461                 pgprot_t prot)
 462 {
 463         phys_addr_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
 464         return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
 465 }
 466 #define io_remap_pfn_range io_remap_pfn_range
 467 #endif
 468
 469 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 470
 471 extern int has_transparent_hugepage(void);
 472
 473 static inline int pmd_trans_huge(pmd_t pmd)
 474 {
 475         return !!(pmd_val(pmd) & _PAGE_HUGE);
 476 }
 477
 478 static inline pmd_t pmd_mkhuge(pmd_t pmd)
 479 {
 480         pmd_val(pmd) |= _PAGE_HUGE;
 481
 482         return pmd;
 483 }
 484
 485 static inline int pmd_trans_splitting(pmd_t pmd)
 486 {
 487         return !!(pmd_val(pmd) & _PAGE_SPLITTING);
 488 }
 489
 490 static inline pmd_t pmd_mksplitting(pmd_t pmd)
 491 {
 492         pmd_val(pmd) |= _PAGE_SPLITTING;
 493
 494         return pmd;
 495 }
 496
 497 extern void set_pmd_at(struct mm_struct *mm, unsigned long addr,
 498                        pmd_t *pmdp, pmd_t pmd);
 499
 500 #define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
 501 /* Extern to avoid header file madness */
 502 extern void pmdp_splitting_flush(struct vm_area_struct *vma,
 503                                         unsigned long address,
 504                                         pmd_t *pmdp);
 505
 506 #define __HAVE_ARCH_PMD_WRITE
 507 static inline int pmd_write(pmd_t pmd)
 508 {
 509         return !!(pmd_val(pmd) & _PAGE_WRITE);
 510 }
 511
 512 static inline pmd_t pmd_wrprotect(pmd_t pmd)
 513 {
 514         pmd_val(pmd) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 515         return pmd;
 516 }
 517
 518 static inline pmd_t pmd_mkwrite(pmd_t pmd)
 519 {
 520         pmd_val(pmd) |= _PAGE_WRITE;
 521         if (pmd_val(pmd) & _PAGE_MODIFIED)
 522                 pmd_val(pmd) |= _PAGE_SILENT_WRITE;
 523
 524         return pmd;
 525 }
 526
 527 static inline int pmd_dirty(pmd_t pmd)
 528 {
 529         return !!(pmd_val(pmd) & _PAGE_MODIFIED);
 530 }
 531
 532 static inline pmd_t pmd_mkclean(pmd_t pmd)
 533 {
 534         pmd_val(pmd) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
 535         return pmd;
 536 }
 537
 538 static inline pmd_t pmd_mkdirty(pmd_t pmd)
 539 {
 540         pmd_val(pmd) |= _PAGE_MODIFIED;
 541         if (pmd_val(pmd) & _PAGE_WRITE)
 542                 pmd_val(pmd) |= _PAGE_SILENT_WRITE;
 543
 544         return pmd;
 545 }
 546
 547 static inline int pmd_young(pmd_t pmd)
 548 {
 549         return !!(pmd_val(pmd) & _PAGE_ACCESSED);
 550 }
 551
 552 static inline pmd_t pmd_mkold(pmd_t pmd)
 553 {
 554         pmd_val(pmd) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
 555
 556         return pmd;
 557 }
 558
 559 static inline pmd_t pmd_mkyoung(pmd_t pmd)
 560 {
 561         pmd_val(pmd) |= _PAGE_ACCESSED;
 562
 563 #ifdef CONFIG_CPU_MIPSR2
 564         if (!(pmd_val(pmd) & _PAGE_NO_READ))
 565                 pmd_val(pmd) |= _PAGE_SILENT_READ;
 566         else
 567 #endif
 568         if (pmd_val(pmd) & _PAGE_READ)
 569                 pmd_val(pmd) |= _PAGE_SILENT_READ;
 570
 571         return pmd;
 572 }
 573
 574 /* Extern to avoid header file madness */
 575 extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
 576
 577 static inline unsigned long pmd_pfn(pmd_t pmd)
 578 {
 579         return pmd_val(pmd) >> _PFN_SHIFT;
 580 }
 581
 582 static inline struct page *pmd_page(pmd_t pmd)
 583 {
 584         if (pmd_trans_huge(pmd))
 585                 return pfn_to_page(pmd_pfn(pmd));
 586
 587         return pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT);
 588 }
 589
 590 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 591 {
 592         pmd_val(pmd) = (pmd_val(pmd) & _PAGE_CHG_MASK) | pgprot_val(newprot);
 593         return pmd;
 594 }
 595
 596 static inline pmd_t pmd_mknotpresent(pmd_t pmd)
 597 {
 598         pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY);
 599
 600         return pmd;
 601 }
 602
 603 /*
 604  * The generic version pmdp_huge_get_and_clear uses a version of pmd_clear() with a
 605  * different prototype.
 606  */
 607 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
 608 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
 609                                             unsigned long address, pmd_t *pmdp)
 610 {
 611         pmd_t old = *pmdp;
 612
 613         pmd_clear(pmdp);
 614
 615         return old;
 616 }
 617
 618 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 619
 620 #include <asm-generic/pgtable.h>
 621
 622 /*
 623  * uncached accelerated TLB map for video memory access
 624  */
 625 #ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
 626 #define __HAVE_PHYS_MEM_ACCESS_PROT
 627
 628 struct file;
 629 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 630                 unsigned long size, pgprot_t vma_prot);
 631 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
 632                 unsigned long size, pgprot_t *vma_prot);
 633 #endif
 634
 635 /*
 636  * We provide our own get_unmapped area to cope with the virtual aliasing
 637  * constraints placed on us by the cache architecture.
 638  */
 639 #define HAVE_ARCH_UNMAPPED_AREA
 640 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 641
 642 /*
 643  * No page table caches to initialise
 644  */
 645 #define pgtable_cache_init()    do { } while (0)
 646
 647 #endif /* _ASM_PGTABLE_H */