LXR linux/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/cmpxchg.h>
  21#include <asm/io.h>
  22#include <asm/pgtable-bits.h>
  23#include <asm/cpu-features.h>
  24
  25struct mm_struct;
  26struct vm_area_struct;
  27
  28#define PAGE_NONE       __pgprot(_PAGE_PRESENT | _PAGE_NO_READ | \
  29                                 _page_cachable_default)
  30#define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
  31                                 _page_cachable_default)
  32#define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_NO_EXEC | \
  33                                 _page_cachable_default)
  34#define PAGE_READONLY   __pgprot(_PAGE_PRESENT | \
  35                                 _page_cachable_default)
  36#define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
  37                                 _PAGE_GLOBAL | _page_cachable_default)
  38#define PAGE_KERNEL_NC  __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
  39                                 _PAGE_GLOBAL | _CACHE_CACHABLE_NONCOHERENT)
  40#define PAGE_USERIO     __pgprot(_PAGE_PRESENT | _PAGE_WRITE | \
  41                                 _page_cachable_default)
  42#define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
  43                        __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
  44
  45/*
  46 * If _PAGE_NO_EXEC is not defined, we can't do page protection for
  47 * execute, and consider it to be the same as read. Also, write
  48 * permissions imply read permissions. This is the closest we can get
  49 * by reasonable means..
  50 */
  51
  52/*
  53 * Dummy values to fill the table in mmap.c
  54 * The real values will be generated at runtime
  55 */
  56#define __P000 __pgprot(0)
  57#define __P001 __pgprot(0)
  58#define __P010 __pgprot(0)
  59#define __P011 __pgprot(0)
  60#define __P100 __pgprot(0)
  61#define __P101 __pgprot(0)
  62#define __P110 __pgprot(0)
  63#define __P111 __pgprot(0)
  64
  65#define __S000 __pgprot(0)
  66#define __S001 __pgprot(0)
  67#define __S010 __pgprot(0)
  68#define __S011 __pgprot(0)
  69#define __S100 __pgprot(0)
  70#define __S101 __pgprot(0)
  71#define __S110 __pgprot(0)
  72#define __S111 __pgprot(0)
  73
  74extern unsigned long _page_cachable_default;
  75
  76/*
  77 * ZERO_PAGE is a global shared page that is always zero; used
  78 * for zero-mapped memory areas etc..
  79 */
  80
  81extern unsigned long empty_zero_page;
  82extern unsigned long zero_page_mask;
  83
  84#define ZERO_PAGE(vaddr) \
  85        (virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
  86#define __HAVE_COLOR_ZERO_PAGE
  87
  88extern void paging_init(void);
  89
  90/*
  91 * Conversion functions: convert a page and protection to a page entry,
  92 * and a page entry and page directory to the page they refer to.
  93 */
  94#define pmd_phys(pmd)           virt_to_phys((void *)pmd_val(pmd))
  95
  96#define __pmd_page(pmd)         (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
  97#ifndef CONFIG_TRANSPARENT_HUGEPAGE
  98#define pmd_page(pmd)           __pmd_page(pmd)
  99#endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
 100
 101#define pmd_page_vaddr(pmd)     pmd_val(pmd)
 102
 103#define htw_stop()                                                      \
 104do {                                                                    \
 105        unsigned long flags;                                            \
 106                                                                        \
 107        if (cpu_has_htw) {                                              \
 108                local_irq_save(flags);                                  \
 109                if(!raw_current_cpu_data.htw_seq++) {                   \
 110                        write_c0_pwctl(read_c0_pwctl() &                \
 111                                       ~(1 << MIPS_PWCTL_PWEN_SHIFT));  \
 112                        back_to_back_c0_hazard();                       \
 113                }                                                       \
 114                local_irq_restore(flags);                               \
 115        }                                                               \
 116} while(0)
 117
 118#define htw_start()                                                     \
 119do {                                                                    \
 120        unsigned long flags;                                            \
 121                                                                        \
 122        if (cpu_has_htw) {                                              \
 123                local_irq_save(flags);                                  \
 124                if (!--raw_current_cpu_data.htw_seq) {                  \
 125                        write_c0_pwctl(read_c0_pwctl() |                \
 126                                       (1 << MIPS_PWCTL_PWEN_SHIFT));   \
 127                        back_to_back_c0_hazard();                       \
 128                }                                                       \
 129                local_irq_restore(flags);                               \
 130        }                                                               \
 131} while(0)
 132
 133static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 134                              pte_t *ptep, pte_t pteval);
 135
 136#if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 137
 138#ifdef CONFIG_XPA
 139# define pte_none(pte)          (!(((pte).pte_high) & ~_PAGE_GLOBAL))
 140#else
 141# define pte_none(pte)          (!(((pte).pte_low | (pte).pte_high) & ~_PAGE_GLOBAL))
 142#endif
 143
 144#define pte_present(pte)        ((pte).pte_low & _PAGE_PRESENT)
 145#define pte_no_exec(pte)        ((pte).pte_low & _PAGE_NO_EXEC)
 146
 147static inline void set_pte(pte_t *ptep, pte_t pte)
 148{
 149        ptep->pte_high = pte.pte_high;
 150        smp_wmb();
 151        ptep->pte_low = pte.pte_low;
 152
 153#ifdef CONFIG_XPA
 154        if (pte.pte_high & _PAGE_GLOBAL) {
 155#else
 156        if (pte.pte_low & _PAGE_GLOBAL) {
 157#endif
 158                pte_t *buddy = ptep_buddy(ptep);
 159                /*
 160                 * Make sure the buddy is global too (if it's !none,
 161                 * it better already be global)
 162                 */
 163                if (pte_none(*buddy)) {
 164                        if (!IS_ENABLED(CONFIG_XPA))
 165                                buddy->pte_low |= _PAGE_GLOBAL;
 166                        buddy->pte_high |= _PAGE_GLOBAL;
 167                }
 168        }
 169}
 170
 171static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 172{
 173        pte_t null = __pte(0);
 174
 175        htw_stop();
 176        /* Preserve global status for the pair */
 177        if (IS_ENABLED(CONFIG_XPA)) {
 178                if (ptep_buddy(ptep)->pte_high & _PAGE_GLOBAL)
 179                        null.pte_high = _PAGE_GLOBAL;
 180        } else {
 181                if (ptep_buddy(ptep)->pte_low & _PAGE_GLOBAL)
 182                        null.pte_low = null.pte_high = _PAGE_GLOBAL;
 183        }
 184
 185        set_pte_at(mm, addr, ptep, null);
 186        htw_start();
 187}
 188#else
 189
 190#define pte_none(pte)           (!(pte_val(pte) & ~_PAGE_GLOBAL))
 191#define pte_present(pte)        (pte_val(pte) & _PAGE_PRESENT)
 192#define pte_no_exec(pte)        (pte_val(pte) & _PAGE_NO_EXEC)
 193
 194/*
 195 * Certain architectures need to do special things when pte's
 196 * within a page table are directly modified.  Thus, the following
 197 * hook is made available.
 198 */
 199static inline void set_pte(pte_t *ptep, pte_t pteval)
 200{
 201        *ptep = pteval;
 202#if !defined(CONFIG_CPU_R3K_TLB)
 203        if (pte_val(pteval) & _PAGE_GLOBAL) {
 204                pte_t *buddy = ptep_buddy(ptep);
 205                /*
 206                 * Make sure the buddy is global too (if it's !none,
 207                 * it better already be global)
 208                 */
 209# if defined(CONFIG_PHYS_ADDR_T_64BIT) && !defined(CONFIG_CPU_MIPS32)
 210                cmpxchg64(&buddy->pte, 0, _PAGE_GLOBAL);
 211# else
 212                cmpxchg(&buddy->pte, 0, _PAGE_GLOBAL);
 213# endif
 214        }
 215#endif
 216}
 217
 218static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 219{
 220        htw_stop();
 221#if !defined(CONFIG_CPU_R3K_TLB)
 222        /* Preserve global status for the pair */
 223        if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
 224                set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
 225        else
 226#endif
 227                set_pte_at(mm, addr, ptep, __pte(0));
 228        htw_start();
 229}
 230#endif
 231
 232static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 233                              pte_t *ptep, pte_t pteval)
 234{
 235        extern void __update_cache(unsigned long address, pte_t pte);
 236
 237        if (!pte_present(pteval))
 238                goto cache_sync_done;
 239
 240        if (pte_present(*ptep) && (pte_pfn(*ptep) == pte_pfn(pteval)))
 241                goto cache_sync_done;
 242
 243        __update_cache(addr, pteval);
 244cache_sync_done:
 245        set_pte(ptep, pteval);
 246}
 247
 248/*
 249 * (pmds are folded into puds so this doesn't get actually called,
 250 * but the define is needed for a generic inline function.)
 251 */
 252#define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)
 253
 254#ifndef __PAGETABLE_PMD_FOLDED
 255/*
 256 * (puds are folded into pgds so this doesn't get actually called,
 257 * but the define is needed for a generic inline function.)
 258 */
 259#define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
 260#endif
 261
 262#define PGD_T_LOG2      (__builtin_ffs(sizeof(pgd_t)) - 1)
 263#define PMD_T_LOG2      (__builtin_ffs(sizeof(pmd_t)) - 1)
 264#define PTE_T_LOG2      (__builtin_ffs(sizeof(pte_t)) - 1)
 265
 266/*
 267 * We used to declare this array with size but gcc 3.3 and older are not able
 268 * to find that this expression is a constant, so the size is dropped.
 269 */
 270extern pgd_t swapper_pg_dir[];
 271
 272/*
 273 * The following only work if pte_present() is true.
 274 * Undefined behaviour if not..
 275 */
 276#if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 277static inline int pte_write(pte_t pte)  { return pte.pte_low & _PAGE_WRITE; }
 278static inline int pte_dirty(pte_t pte)  { return pte.pte_low & _PAGE_MODIFIED; }
 279static inline int pte_young(pte_t pte)  { return pte.pte_low & _PAGE_ACCESSED; }
 280static inline int pte_special(pte_t pte) { return pte.pte_low & _PAGE_SPECIAL; }
 281
 282static inline pte_t pte_wrprotect(pte_t pte)
 283{
 284        pte.pte_low  &= ~_PAGE_WRITE;
 285        if (!IS_ENABLED(CONFIG_XPA))
 286                pte.pte_low &= ~_PAGE_SILENT_WRITE;
 287        pte.pte_high &= ~_PAGE_SILENT_WRITE;
 288        return pte;
 289}
 290
 291static inline pte_t pte_mkclean(pte_t pte)
 292{
 293        pte.pte_low  &= ~_PAGE_MODIFIED;
 294        if (!IS_ENABLED(CONFIG_XPA))
 295                pte.pte_low &= ~_PAGE_SILENT_WRITE;
 296        pte.pte_high &= ~_PAGE_SILENT_WRITE;
 297        return pte;
 298}
 299
 300static inline pte_t pte_mkold(pte_t pte)
 301{
 302        pte.pte_low  &= ~_PAGE_ACCESSED;
 303        if (!IS_ENABLED(CONFIG_XPA))
 304                pte.pte_low &= ~_PAGE_SILENT_READ;
 305        pte.pte_high &= ~_PAGE_SILENT_READ;
 306        return pte;
 307}
 308
 309static inline pte_t pte_mkwrite(pte_t pte)
 310{
 311        pte.pte_low |= _PAGE_WRITE;
 312        if (pte.pte_low & _PAGE_MODIFIED) {
 313                if (!IS_ENABLED(CONFIG_XPA))
 314                        pte.pte_low |= _PAGE_SILENT_WRITE;
 315                pte.pte_high |= _PAGE_SILENT_WRITE;
 316        }
 317        return pte;
 318}
 319
 320static inline pte_t pte_mkdirty(pte_t pte)
 321{
 322        pte.pte_low |= _PAGE_MODIFIED;
 323        if (pte.pte_low & _PAGE_WRITE) {
 324                if (!IS_ENABLED(CONFIG_XPA))
 325                        pte.pte_low |= _PAGE_SILENT_WRITE;
 326                pte.pte_high |= _PAGE_SILENT_WRITE;
 327        }
 328        return pte;
 329}
 330
 331static inline pte_t pte_mkyoung(pte_t pte)
 332{
 333        pte.pte_low |= _PAGE_ACCESSED;
 334        if (!(pte.pte_low & _PAGE_NO_READ)) {
 335                if (!IS_ENABLED(CONFIG_XPA))
 336                        pte.pte_low |= _PAGE_SILENT_READ;
 337                pte.pte_high |= _PAGE_SILENT_READ;
 338        }
 339        return pte;
 340}
 341
 342static inline pte_t pte_mkspecial(pte_t pte)
 343{
 344        pte.pte_low |= _PAGE_SPECIAL;
 345        return pte;
 346}
 347#else
 348static inline int pte_write(pte_t pte)  { return pte_val(pte) & _PAGE_WRITE; }
 349static inline int pte_dirty(pte_t pte)  { return pte_val(pte) & _PAGE_MODIFIED; }
 350static inline int pte_young(pte_t pte)  { return pte_val(pte) & _PAGE_ACCESSED; }
 351static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; }
 352
 353static inline pte_t pte_wrprotect(pte_t pte)
 354{
 355        pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 356        return pte;
 357}
 358
 359static inline pte_t pte_mkclean(pte_t pte)
 360{
 361        pte_val(pte) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
 362        return pte;
 363}
 364
 365static inline pte_t pte_mkold(pte_t pte)
 366{
 367        pte_val(pte) &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
 368        return pte;
 369}
 370
 371static inline pte_t pte_mkwrite(pte_t pte)
 372{
 373        pte_val(pte) |= _PAGE_WRITE;
 374        if (pte_val(pte) & _PAGE_MODIFIED)
 375                pte_val(pte) |= _PAGE_SILENT_WRITE;
 376        return pte;
 377}
 378
 379static inline pte_t pte_mkdirty(pte_t pte)
 380{
 381        pte_val(pte) |= _PAGE_MODIFIED;
 382        if (pte_val(pte) & _PAGE_WRITE)
 383                pte_val(pte) |= _PAGE_SILENT_WRITE;
 384        return pte;
 385}
 386
 387static inline pte_t pte_mkyoung(pte_t pte)
 388{
 389        pte_val(pte) |= _PAGE_ACCESSED;
 390        if (!(pte_val(pte) & _PAGE_NO_READ))
 391                pte_val(pte) |= _PAGE_SILENT_READ;
 392        return pte;
 393}
 394
 395static inline pte_t pte_mkspecial(pte_t pte)
 396{
 397        pte_val(pte) |= _PAGE_SPECIAL;
 398        return pte;
 399}
 400
 401#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
 402static inline int pte_huge(pte_t pte)   { return pte_val(pte) & _PAGE_HUGE; }
 403
 404static inline pte_t pte_mkhuge(pte_t pte)
 405{
 406        pte_val(pte) |= _PAGE_HUGE;
 407        return pte;
 408}
 409#endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
 410#endif
 411
 412/*
 413 * Macro to make mark a page protection value as "uncacheable".  Note
 414 * that "protection" is really a misnomer here as the protection value
 415 * contains the memory attribute bits, dirty bits, and various other
 416 * bits as well.
 417 */
 418#define pgprot_noncached pgprot_noncached
 419
 420static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 421{
 422        unsigned long prot = pgprot_val(_prot);
 423
 424        prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
 425
 426        return __pgprot(prot);
 427}
 428
 429#define pgprot_writecombine pgprot_writecombine
 430
 431static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
 432{
 433        unsigned long prot = pgprot_val(_prot);
 434
 435        /* cpu_data[0].writecombine is already shifted by _CACHE_SHIFT */
 436        prot = (prot & ~_CACHE_MASK) | cpu_data[0].writecombine;
 437
 438        return __pgprot(prot);
 439}
 440
 441/*
 442 * Conversion functions: convert a page and protection to a page entry,
 443 * and a page entry and page directory to the page they refer to.
 444 */
 445#define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 446
 447#if defined(CONFIG_XPA)
 448static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 449{
 450        pte.pte_low  &= (_PAGE_MODIFIED | _PAGE_ACCESSED | _PFNX_MASK);
 451        pte.pte_high &= (_PFN_MASK | _CACHE_MASK);
 452        pte.pte_low  |= pgprot_val(newprot) & ~_PFNX_MASK;
 453        pte.pte_high |= pgprot_val(newprot) & ~(_PFN_MASK | _CACHE_MASK);
 454        return pte;
 455}
 456#elif defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
 457static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 458{
 459        pte.pte_low  &= _PAGE_CHG_MASK;
 460        pte.pte_high &= (_PFN_MASK | _CACHE_MASK);
 461        pte.pte_low  |= pgprot_val(newprot);
 462        pte.pte_high |= pgprot_val(newprot) & ~(_PFN_MASK | _CACHE_MASK);
 463        return pte;
 464}
 465#else
 466static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 467{
 468        return __pte((pte_val(pte) & _PAGE_CHG_MASK) |
 469                     (pgprot_val(newprot) & ~_PAGE_CHG_MASK));
 470}
 471#endif
 472
 473
 474extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
 475        pte_t pte);
 476
 477static inline void update_mmu_cache(struct vm_area_struct *vma,
 478        unsigned long address, pte_t *ptep)
 479{
 480        pte_t pte = *ptep;
 481        __update_tlb(vma, address, pte);
 482}
 483
 484static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
 485        unsigned long address, pmd_t *pmdp)
 486{
 487        pte_t pte = *(pte_t *)pmdp;
 488
 489        __update_tlb(vma, address, pte);
 490}
 491
 492#define kern_addr_valid(addr)   (1)
 493
 494#ifdef CONFIG_PHYS_ADDR_T_64BIT
 495extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);
 496
 497static inline int io_remap_pfn_range(struct vm_area_struct *vma,
 498                unsigned long vaddr,
 499                unsigned long pfn,
 500                unsigned long size,
 501                pgprot_t prot)
 502{
 503        phys_addr_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
 504        return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
 505}
 506#define io_remap_pfn_range io_remap_pfn_range
 507#endif
 508
 509#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 510
 511/* We don't have hardware dirty/accessed bits, generic_pmdp_establish is fine.*/
 512#define pmdp_establish generic_pmdp_establish
 513
 514#define has_transparent_hugepage has_transparent_hugepage
 515extern int has_transparent_hugepage(void);
 516
 517static inline int pmd_trans_huge(pmd_t pmd)
 518{
 519        return !!(pmd_val(pmd) & _PAGE_HUGE);
 520}
 521
 522static inline pmd_t pmd_mkhuge(pmd_t pmd)
 523{
 524        pmd_val(pmd) |= _PAGE_HUGE;
 525
 526        return pmd;
 527}
 528
 529extern void set_pmd_at(struct mm_struct *mm, unsigned long addr,
 530                       pmd_t *pmdp, pmd_t pmd);
 531
 532#define pmd_write pmd_write
 533static inline int pmd_write(pmd_t pmd)
 534{
 535        return !!(pmd_val(pmd) & _PAGE_WRITE);
 536}
 537
 538static inline pmd_t pmd_wrprotect(pmd_t pmd)
 539{
 540        pmd_val(pmd) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 541        return pmd;
 542}
 543
 544static inline pmd_t pmd_mkwrite(pmd_t pmd)
 545{
 546        pmd_val(pmd) |= _PAGE_WRITE;
 547        if (pmd_val(pmd) & _PAGE_MODIFIED)
 548                pmd_val(pmd) |= _PAGE_SILENT_WRITE;
 549
 550        return pmd;
 551}
 552
 553static inline int pmd_dirty(pmd_t pmd)
 554{
 555        return !!(pmd_val(pmd) & _PAGE_MODIFIED);
 556}
 557
 558static inline pmd_t pmd_mkclean(pmd_t pmd)
 559{
 560        pmd_val(pmd) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
 561        return pmd;
 562}
 563
 564static inline pmd_t pmd_mkdirty(pmd_t pmd)
 565{
 566        pmd_val(pmd) |= _PAGE_MODIFIED;
 567        if (pmd_val(pmd) & _PAGE_WRITE)
 568                pmd_val(pmd) |= _PAGE_SILENT_WRITE;
 569
 570        return pmd;
 571}
 572
 573static inline int pmd_young(pmd_t pmd)
 574{
 575        return !!(pmd_val(pmd) & _PAGE_ACCESSED);
 576}
 577
 578static inline pmd_t pmd_mkold(pmd_t pmd)
 579{
 580        pmd_val(pmd) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
 581
 582        return pmd;
 583}
 584
 585static inline pmd_t pmd_mkyoung(pmd_t pmd)
 586{
 587        pmd_val(pmd) |= _PAGE_ACCESSED;
 588
 589        if (!(pmd_val(pmd) & _PAGE_NO_READ))
 590                pmd_val(pmd) |= _PAGE_SILENT_READ;
 591
 592        return pmd;
 593}
 594
 595/* Extern to avoid header file madness */
 596extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
 597
 598static inline unsigned long pmd_pfn(pmd_t pmd)
 599{
 600        return pmd_val(pmd) >> _PFN_SHIFT;
 601}
 602
 603static inline struct page *pmd_page(pmd_t pmd)
 604{
 605        if (pmd_trans_huge(pmd))
 606                return pfn_to_page(pmd_pfn(pmd));
 607
 608        return pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT);
 609}
 610
 611static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
 612{
 613        pmd_val(pmd) = (pmd_val(pmd) & (_PAGE_CHG_MASK | _PAGE_HUGE)) |
 614                       (pgprot_val(newprot) & ~_PAGE_CHG_MASK);
 615        return pmd;
 616}
 617
 618static inline pmd_t pmd_mknotpresent(pmd_t pmd)
 619{
 620        pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY);
 621
 622        return pmd;
 623}
 624
 625/*
 626 * The generic version pmdp_huge_get_and_clear uses a version of pmd_clear() with a
 627 * different prototype.
 628 */
 629#define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
 630static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
 631                                            unsigned long address, pmd_t *pmdp)
 632{
 633        pmd_t old = *pmdp;
 634
 635        pmd_clear(pmdp);
 636
 637        return old;
 638}
 639
 640#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 641
 642#ifdef _PAGE_HUGE
 643#define pmd_leaf(pmd)   ((pmd_val(pmd) & _PAGE_HUGE) != 0)
 644#define pud_leaf(pud)   ((pud_val(pud) & _PAGE_HUGE) != 0)
 645#endif
 646
 647#define gup_fast_permitted(start, end)  (!cpu_has_dc_aliases)
 648
 649#include <asm-generic/pgtable.h>
 650
 651/*
 652 * We provide our own get_unmapped area to cope with the virtual aliasing
 653 * constraints placed on us by the cache architecture.
 654 */
 655#define HAVE_ARCH_UNMAPPED_AREA
 656#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 657
 658#endif /* _ASM_PGTABLE_H */
 659