LXR linux/arch/parisc/include/asm/pgtable.h

   1#ifndef _PARISC_PGTABLE_H
   2#define _PARISC_PGTABLE_H
   3
   4#include <asm-generic/4level-fixup.h>
   5
   6#include <asm/fixmap.h>
   7
   8#ifndef __ASSEMBLY__
   9/*
  10 * we simulate an x86-style page table for the linux mm code
  11 */
  12
  13#include <linux/bitops.h>
  14#include <linux/spinlock.h>
  15#include <asm/processor.h>
  16#include <asm/cache.h>
  17
  18struct vm_area_struct;
  19
  20/*
  21 * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
  22 * memory.  For the return value to be meaningful, ADDR must be >=
  23 * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
  24 * require a hash-, or multi-level tree-lookup or something of that
  25 * sort) but it guarantees to return TRUE only if accessing the page
  26 * at that address does not cause an error.  Note that there may be
  27 * addresses for which kern_addr_valid() returns FALSE even though an
  28 * access would not cause an error (e.g., this is typically true for
  29 * memory mapped I/O regions.
  30 *
  31 * XXX Need to implement this for parisc.
  32 */
  33#define kern_addr_valid(addr)   (1)
  34
  35/* Certain architectures need to do special things when PTEs
  36 * within a page table are directly modified.  Thus, the following
  37 * hook is made available.
  38 */
  39#define set_pte(pteptr, pteval)                                 \
  40        do{                                                     \
  41                *(pteptr) = (pteval);                           \
  42        } while(0)
  43#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
  44
  45#endif /* !__ASSEMBLY__ */
  46
  47#define pte_ERROR(e) \
  48        printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
  49#define pmd_ERROR(e) \
  50        printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
  51#define pgd_ERROR(e) \
  52        printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
  53
  54/* This is the size of the initially mapped kernel memory */
  55#define KERNEL_INITIAL_ORDER    24      /* 0 to 1<<24 = 16MB */
  56#define KERNEL_INITIAL_SIZE     (1 << KERNEL_INITIAL_ORDER)
  57
  58#if defined(CONFIG_64BIT) && defined(CONFIG_PARISC_PAGE_SIZE_4KB)
  59#define PT_NLEVELS      3
  60#define PGD_ORDER       1 /* Number of pages per pgd */
  61#define PMD_ORDER       1 /* Number of pages per pmd */
  62#define PGD_ALLOC_ORDER 2 /* first pgd contains pmd */
  63#else
  64#define PT_NLEVELS      2
  65#define PGD_ORDER       1 /* Number of pages per pgd */
  66#define PGD_ALLOC_ORDER PGD_ORDER
  67#endif
  68
  69/* Definitions for 3rd level (we use PLD here for Page Lower directory
  70 * because PTE_SHIFT is used lower down to mean shift that has to be
  71 * done to get usable bits out of the PTE) */
  72#define PLD_SHIFT       PAGE_SHIFT
  73#define PLD_SIZE        PAGE_SIZE
  74#define BITS_PER_PTE    (PAGE_SHIFT - BITS_PER_PTE_ENTRY)
  75#define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
  76
  77/* Definitions for 2nd level */
  78#define pgtable_cache_init()    do { } while (0)
  79
  80#define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
  81#define PMD_SIZE        (1UL << PMD_SHIFT)
  82#define PMD_MASK        (~(PMD_SIZE-1))
  83#if PT_NLEVELS == 3
  84#define BITS_PER_PMD    (PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
  85#else
  86#define BITS_PER_PMD    0
  87#endif
  88#define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
  89
  90/* Definitions for 1st level */
  91#define PGDIR_SHIFT     (PMD_SHIFT + BITS_PER_PMD)
  92#if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
  93#define BITS_PER_PGD    (BITS_PER_LONG - PGDIR_SHIFT)
  94#else
  95#define BITS_PER_PGD    (PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
  96#endif
  97#define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  98#define PGDIR_MASK      (~(PGDIR_SIZE-1))
  99#define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
 100#define USER_PTRS_PER_PGD       PTRS_PER_PGD
 101
 102#ifdef CONFIG_64BIT
 103#define MAX_ADDRBITS    (PGDIR_SHIFT + BITS_PER_PGD)
 104#define MAX_ADDRESS     (1UL << MAX_ADDRBITS)
 105#define SPACEID_SHIFT   (MAX_ADDRBITS - 32)
 106#else
 107#define MAX_ADDRBITS    (BITS_PER_LONG)
 108#define MAX_ADDRESS     (1UL << MAX_ADDRBITS)
 109#define SPACEID_SHIFT   0
 110#endif
 111
 112/* This calculates the number of initial pages we need for the initial
 113 * page tables */
 114#if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
 115# define PT_INITIAL     (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
 116#else
 117# define PT_INITIAL     (1)  /* all initial PTEs fit into one page */
 118#endif
 119
 120/*
 121 * pgd entries used up by user/kernel:
 122 */
 123
 124#define FIRST_USER_ADDRESS      0
 125
 126/* NB: The tlb miss handlers make certain assumptions about the order */
 127/*     of the following bits, so be careful (One example, bits 25-31  */
 128/*     are moved together in one instruction).                        */
 129
 130#define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
 131#define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
 132#define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
 133#define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
 134#define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
 135#define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
 136#define _PAGE_FILE_BIT  _PAGE_DIRTY_BIT /* overload this bit */
 137#define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
 138#define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
 139#define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
 140#define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
 141/* bit 21 was formerly the FLUSH bit but is now unused */
 142#define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
 143
 144/* N.B. The bits are defined in terms of a 32 bit word above, so the */
 145/*      following macro is ok for both 32 and 64 bit.                */
 146
 147#define xlate_pabit(x) (31 - x)
 148
 149/* this defines the shift to the usable bits in the PTE it is set so
 150 * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
 151 * to zero */
 152#define PTE_SHIFT               xlate_pabit(_PAGE_USER_BIT)
 153
 154/* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
 155#define PFN_PTE_SHIFT           12
 156
 157
 158/* this is how many bits may be used by the file functions */
 159#define PTE_FILE_MAX_BITS       (BITS_PER_LONG - PTE_SHIFT)
 160
 161#define pte_to_pgoff(pte) (pte_val(pte) >> PTE_SHIFT)
 162#define pgoff_to_pte(off) ((pte_t) { ((off) << PTE_SHIFT) | _PAGE_FILE })
 163
 164#define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
 165#define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
 166#define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
 167#define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
 168#define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
 169#define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
 170#define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
 171#define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
 172#define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
 173#define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
 174#define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
 175#define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
 176#define _PAGE_FILE     (1 << xlate_pabit(_PAGE_FILE_BIT))
 177
 178#define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE |  _PAGE_DIRTY | _PAGE_ACCESSED)
 179#define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
 180#define _PAGE_KERNEL_RO (_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
 181#define _PAGE_KERNEL_EXEC       (_PAGE_KERNEL_RO | _PAGE_EXEC)
 182#define _PAGE_KERNEL_RWX        (_PAGE_KERNEL_EXEC | _PAGE_WRITE)
 183#define _PAGE_KERNEL            (_PAGE_KERNEL_RO | _PAGE_WRITE)
 184
 185/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
 186 * are page-aligned, we don't care about the PAGE_OFFSET bits, except
 187 * for a few meta-information bits, so we shift the address to be
 188 * able to effectively address 40/42/44-bits of physical address space
 189 * depending on 4k/16k/64k PAGE_SIZE */
 190#define _PxD_PRESENT_BIT   31
 191#define _PxD_ATTACHED_BIT  30
 192#define _PxD_VALID_BIT     29
 193
 194#define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
 195#define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
 196#define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
 197#define PxD_FLAG_MASK     (0xf)
 198#define PxD_FLAG_SHIFT    (4)
 199#define PxD_VALUE_SHIFT   (8) /* (PAGE_SHIFT-PxD_FLAG_SHIFT) */
 200
 201#ifndef __ASSEMBLY__
 202
 203#define PAGE_NONE       __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
 204#define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_ACCESSED)
 205/* Others seem to make this executable, I don't know if that's correct
 206   or not.  The stack is mapped this way though so this is necessary
 207   in the short term - dhd@linuxcare.com, 2000-08-08 */
 208#define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_ACCESSED)
 209#define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE | _PAGE_ACCESSED)
 210#define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC |_PAGE_ACCESSED)
 211#define PAGE_COPY       PAGE_EXECREAD
 212#define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |_PAGE_ACCESSED)
 213#define PAGE_KERNEL     __pgprot(_PAGE_KERNEL)
 214#define PAGE_KERNEL_EXEC        __pgprot(_PAGE_KERNEL_EXEC)
 215#define PAGE_KERNEL_RWX __pgprot(_PAGE_KERNEL_RWX)
 216#define PAGE_KERNEL_RO  __pgprot(_PAGE_KERNEL_RO)
 217#define PAGE_KERNEL_UNC __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
 218#define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)
 219
 220
 221/*
 222 * We could have an execute only page using "gateway - promote to priv
 223 * level 3", but that is kind of silly. So, the way things are defined
 224 * now, we must always have read permission for pages with execute
 225 * permission. For the fun of it we'll go ahead and support write only
 226 * pages.
 227 */
 228
 229         /*xwr*/
 230#define __P000  PAGE_NONE
 231#define __P001  PAGE_READONLY
 232#define __P010  __P000 /* copy on write */
 233#define __P011  __P001 /* copy on write */
 234#define __P100  PAGE_EXECREAD
 235#define __P101  PAGE_EXECREAD
 236#define __P110  __P100 /* copy on write */
 237#define __P111  __P101 /* copy on write */
 238
 239#define __S000  PAGE_NONE
 240#define __S001  PAGE_READONLY
 241#define __S010  PAGE_WRITEONLY
 242#define __S011  PAGE_SHARED
 243#define __S100  PAGE_EXECREAD
 244#define __S101  PAGE_EXECREAD
 245#define __S110  PAGE_RWX
 246#define __S111  PAGE_RWX
 247
 248
 249extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
 250
 251/* initial page tables for 0-8MB for kernel */
 252
 253extern pte_t pg0[];
 254
 255/* zero page used for uninitialized stuff */
 256
 257extern unsigned long *empty_zero_page;
 258
 259/*
 260 * ZERO_PAGE is a global shared page that is always zero: used
 261 * for zero-mapped memory areas etc..
 262 */
 263
 264#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
 265
 266#define pte_none(x)     (pte_val(x) == 0)
 267#define pte_present(x)  (pte_val(x) & _PAGE_PRESENT)
 268#define pte_clear(mm,addr,xp)   do { pte_val(*(xp)) = 0; } while (0)
 269
 270#define pmd_flag(x)     (pmd_val(x) & PxD_FLAG_MASK)
 271#define pmd_address(x)  ((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
 272#define pgd_flag(x)     (pgd_val(x) & PxD_FLAG_MASK)
 273#define pgd_address(x)  ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
 274
 275#if PT_NLEVELS == 3
 276/* The first entry of the permanent pmd is not there if it contains
 277 * the gateway marker */
 278#define pmd_none(x)     (!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
 279#else
 280#define pmd_none(x)     (!pmd_val(x))
 281#endif
 282#define pmd_bad(x)      (!(pmd_flag(x) & PxD_FLAG_VALID))
 283#define pmd_present(x)  (pmd_flag(x) & PxD_FLAG_PRESENT)
 284static inline void pmd_clear(pmd_t *pmd) {
 285#if PT_NLEVELS == 3
 286        if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
 287                /* This is the entry pointing to the permanent pmd
 288                 * attached to the pgd; cannot clear it */
 289                __pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
 290        else
 291#endif
 292                __pmd_val_set(*pmd,  0);
 293}
 294
 295
 296
 297#if PT_NLEVELS == 3
 298#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
 299#define pgd_page(pgd)   virt_to_page((void *)pgd_page_vaddr(pgd))
 300
 301/* For 64 bit we have three level tables */
 302
 303#define pgd_none(x)     (!pgd_val(x))
 304#define pgd_bad(x)      (!(pgd_flag(x) & PxD_FLAG_VALID))
 305#define pgd_present(x)  (pgd_flag(x) & PxD_FLAG_PRESENT)
 306static inline void pgd_clear(pgd_t *pgd) {
 307#if PT_NLEVELS == 3
 308        if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
 309                /* This is the permanent pmd attached to the pgd; cannot
 310                 * free it */
 311                return;
 312#endif
 313        __pgd_val_set(*pgd, 0);
 314}
 315#else
 316/*
 317 * The "pgd_xxx()" functions here are trivial for a folded two-level
 318 * setup: the pgd is never bad, and a pmd always exists (as it's folded
 319 * into the pgd entry)
 320 */
 321static inline int pgd_none(pgd_t pgd)           { return 0; }
 322static inline int pgd_bad(pgd_t pgd)            { return 0; }
 323static inline int pgd_present(pgd_t pgd)        { return 1; }
 324static inline void pgd_clear(pgd_t * pgdp)      { }
 325#endif
 326
 327/*
 328 * The following only work if pte_present() is true.
 329 * Undefined behaviour if not..
 330 */
 331static inline int pte_dirty(pte_t pte)          { return pte_val(pte) & _PAGE_DIRTY; }
 332static inline int pte_young(pte_t pte)          { return pte_val(pte) & _PAGE_ACCESSED; }
 333static inline int pte_write(pte_t pte)          { return pte_val(pte) & _PAGE_WRITE; }
 334static inline int pte_file(pte_t pte)           { return pte_val(pte) & _PAGE_FILE; }
 335static inline int pte_special(pte_t pte)        { return 0; }
 336
 337static inline pte_t pte_mkclean(pte_t pte)      { pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
 338static inline pte_t pte_mkold(pte_t pte)        { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
 339static inline pte_t pte_wrprotect(pte_t pte)    { pte_val(pte) &= ~_PAGE_WRITE; return pte; }
 340static inline pte_t pte_mkdirty(pte_t pte)      { pte_val(pte) |= _PAGE_DIRTY; return pte; }
 341static inline pte_t pte_mkyoung(pte_t pte)      { pte_val(pte) |= _PAGE_ACCESSED; return pte; }
 342static inline pte_t pte_mkwrite(pte_t pte)      { pte_val(pte) |= _PAGE_WRITE; return pte; }
 343static inline pte_t pte_mkspecial(pte_t pte)    { return pte; }
 344
 345/*
 346 * Conversion functions: convert a page and protection to a page entry,
 347 * and a page entry and page directory to the page they refer to.
 348 */
 349#define __mk_pte(addr,pgprot) \
 350({                                                                      \
 351        pte_t __pte;                                                    \
 352                                                                        \
 353        pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));  \
 354                                                                        \
 355        __pte;                                                          \
 356})
 357
 358#define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 359
 360static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
 361{
 362        pte_t pte;
 363        pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
 364        return pte;
 365}
 366
 367static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 368{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
 369
 370/* Permanent address of a page.  On parisc we don't have highmem. */
 371
 372#define pte_pfn(x)              (pte_val(x) >> PFN_PTE_SHIFT)
 373
 374#define pte_page(pte)           (pfn_to_page(pte_pfn(pte)))
 375
 376#define pmd_page_vaddr(pmd)     ((unsigned long) __va(pmd_address(pmd)))
 377
 378#define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
 379#define pmd_page(pmd)   virt_to_page((void *)__pmd_page(pmd))
 380
 381#define pgd_index(address) ((address) >> PGDIR_SHIFT)
 382
 383/* to find an entry in a page-table-directory */
 384#define pgd_offset(mm, address) \
 385((mm)->pgd + ((address) >> PGDIR_SHIFT))
 386
 387/* to find an entry in a kernel page-table-directory */
 388#define pgd_offset_k(address) pgd_offset(&init_mm, address)
 389
 390/* Find an entry in the second-level page table.. */
 391
 392#if PT_NLEVELS == 3
 393#define pmd_offset(dir,address) \
 394((pmd_t *) pgd_page_vaddr(*(dir)) + (((address)>>PMD_SHIFT) & (PTRS_PER_PMD-1)))
 395#else
 396#define pmd_offset(dir,addr) ((pmd_t *) dir)
 397#endif
 398
 399/* Find an entry in the third-level page table.. */ 
 400#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
 401#define pte_offset_kernel(pmd, address) \
 402        ((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
 403#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
 404#define pte_unmap(pte) do { } while (0)
 405
 406#define pte_unmap(pte)                  do { } while (0)
 407#define pte_unmap_nested(pte)           do { } while (0)
 408
 409extern void paging_init (void);
 410
 411/* Used for deferring calls to flush_dcache_page() */
 412
 413#define PG_dcache_dirty         PG_arch_1
 414
 415extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
 416
 417/* Encode and de-code a swap entry */
 418
 419#define __swp_type(x)                     ((x).val & 0x1f)
 420#define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
 421                                          (((x).val >> 8) & ~0x7) )
 422#define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
 423                                            ((offset &  0x7) << 6) | \
 424                                            ((offset & ~0x7) << 8) })
 425#define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) })
 426#define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 427
 428static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
 429{
 430#ifdef CONFIG_SMP
 431        if (!pte_young(*ptep))
 432                return 0;
 433        return test_and_clear_bit(xlate_pabit(_PAGE_ACCESSED_BIT), &pte_val(*ptep));
 434#else
 435        pte_t pte = *ptep;
 436        if (!pte_young(pte))
 437                return 0;
 438        set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
 439        return 1;
 440#endif
 441}
 442
 443extern spinlock_t pa_dbit_lock;
 444
 445struct mm_struct;
 446static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 447{
 448        pte_t old_pte;
 449
 450        spin_lock(&pa_dbit_lock);
 451        old_pte = *ptep;
 452        pte_clear(mm,addr,ptep);
 453        spin_unlock(&pa_dbit_lock);
 454
 455        return old_pte;
 456}
 457
 458static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 459{
 460#ifdef CONFIG_SMP
 461        unsigned long new, old;
 462
 463        do {
 464                old = pte_val(*ptep);
 465                new = pte_val(pte_wrprotect(__pte (old)));
 466        } while (cmpxchg((unsigned long *) ptep, old, new) != old);
 467#else
 468        pte_t old_pte = *ptep;
 469        set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
 470#endif
 471}
 472
 473#define pte_same(A,B)   (pte_val(A) == pte_val(B))
 474
 475#endif /* !__ASSEMBLY__ */
 476
 477
 478/* TLB page size encoding - see table 3-1 in parisc20.pdf */
 479#define _PAGE_SIZE_ENCODING_4K          0
 480#define _PAGE_SIZE_ENCODING_16K         1
 481#define _PAGE_SIZE_ENCODING_64K         2
 482#define _PAGE_SIZE_ENCODING_256K        3
 483#define _PAGE_SIZE_ENCODING_1M          4
 484#define _PAGE_SIZE_ENCODING_4M          5
 485#define _PAGE_SIZE_ENCODING_16M         6
 486#define _PAGE_SIZE_ENCODING_64M         7
 487
 488#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
 489# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
 490#elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
 491# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
 492#elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
 493# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
 494#endif
 495
 496
 497#define io_remap_pfn_range(vma, vaddr, pfn, size, prot)         \
 498                remap_pfn_range(vma, vaddr, pfn, size, prot)
 499
 500#define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
 501
 502/* We provide our own get_unmapped_area to provide cache coherency */
 503
 504#define HAVE_ARCH_UNMAPPED_AREA
 505
 506#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 507#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 508#define __HAVE_ARCH_PTEP_SET_WRPROTECT
 509#define __HAVE_ARCH_PTE_SAME
 510#include <asm-generic/pgtable.h>
 511
 512#endif /* _PARISC_PGTABLE_H */
 513