LXR linux/arch/m32r/include/asm/pgtable.h

   1#ifndef _ASM_M32R_PGTABLE_H
   2#define _ASM_M32R_PGTABLE_H
   3
   4#include <asm-generic/4level-fixup.h>
   5
   6#ifdef __KERNEL__
   7/*
   8 * The Linux memory management assumes a three-level page table setup. On
   9 * the M32R, we use that, but "fold" the mid level into the top-level page
  10 * table, so that we physically have the same two-level page table as the
  11 * M32R mmu expects.
  12 *
  13 * This file contains the functions and defines necessary to modify and use
  14 * the M32R page table tree.
  15 */
  16
  17/* CAUTION!: If you change macro definitions in this file, you might have to
  18 * change arch/m32r/mmu.S manually.
  19 */
  20
  21#ifndef __ASSEMBLY__
  22
  23#include <linux/threads.h>
  24#include <linux/bitops.h>
  25#include <asm/processor.h>
  26#include <asm/addrspace.h>
  27#include <asm/page.h>
  28
  29struct mm_struct;
  30struct vm_area_struct;
  31
  32extern pgd_t swapper_pg_dir[1024];
  33extern void paging_init(void);
  34
  35/*
  36 * ZERO_PAGE is a global shared page that is always zero: used
  37 * for zero-mapped memory areas etc..
  38 */
  39extern unsigned long empty_zero_page[1024];
  40#define ZERO_PAGE(vaddr)        (virt_to_page(empty_zero_page))
  41
  42#endif /* !__ASSEMBLY__ */
  43
  44#ifndef __ASSEMBLY__
  45#include <asm/pgtable-2level.h>
  46#endif
  47
  48#define pgtable_cache_init()    do { } while (0)
  49
  50#define PMD_SIZE        (1UL << PMD_SHIFT)
  51#define PMD_MASK        (~(PMD_SIZE - 1))
  52#define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  53#define PGDIR_MASK      (~(PGDIR_SIZE - 1))
  54
  55#define USER_PTRS_PER_PGD       (TASK_SIZE / PGDIR_SIZE)
  56#define FIRST_USER_ADDRESS      0UL
  57
  58#ifndef __ASSEMBLY__
  59/* Just any arbitrary offset to the start of the vmalloc VM area: the
  60 * current 8MB value just means that there will be a 8MB "hole" after the
  61 * physical memory until the kernel virtual memory starts.  That means that
  62 * any out-of-bounds memory accesses will hopefully be caught.
  63 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  64 * area for the same reason. ;)
  65 */
  66#define VMALLOC_START           KSEG2
  67#define VMALLOC_END             KSEG3
  68
  69/*
  70 *     M32R TLB format
  71 *
  72 *     [0]    [1:19]           [20:23]       [24:31]
  73 *     +-----------------------+----+-------------+
  74 *     |          VPN          |0000|    ASID     |
  75 *     +-----------------------+----+-------------+
  76 *     +-+---------------------+----+-+---+-+-+-+-+
  77 *     |0         PPN          |0000|N|AC |L|G|V| |
  78 *     +-+---------------------+----+-+---+-+-+-+-+
  79 *                                     RWX
  80 */
  81
  82#define _PAGE_BIT_DIRTY         0       /* software: page changed */
  83#define _PAGE_BIT_PRESENT       1       /* Valid: page is valid */
  84#define _PAGE_BIT_GLOBAL        2       /* Global */
  85#define _PAGE_BIT_LARGE         3       /* Large */
  86#define _PAGE_BIT_EXEC          4       /* Execute */
  87#define _PAGE_BIT_WRITE         5       /* Write */
  88#define _PAGE_BIT_READ          6       /* Read */
  89#define _PAGE_BIT_NONCACHABLE   7       /* Non cachable */
  90#define _PAGE_BIT_ACCESSED      8       /* software: page referenced */
  91#define _PAGE_BIT_PROTNONE      9       /* software: if not present */
  92
  93#define _PAGE_DIRTY             (1UL << _PAGE_BIT_DIRTY)
  94#define _PAGE_PRESENT           (1UL << _PAGE_BIT_PRESENT)
  95#define _PAGE_GLOBAL            (1UL << _PAGE_BIT_GLOBAL)
  96#define _PAGE_LARGE             (1UL << _PAGE_BIT_LARGE)
  97#define _PAGE_EXEC              (1UL << _PAGE_BIT_EXEC)
  98#define _PAGE_WRITE             (1UL << _PAGE_BIT_WRITE)
  99#define _PAGE_READ              (1UL << _PAGE_BIT_READ)
 100#define _PAGE_NONCACHABLE       (1UL << _PAGE_BIT_NONCACHABLE)
 101#define _PAGE_ACCESSED          (1UL << _PAGE_BIT_ACCESSED)
 102#define _PAGE_PROTNONE          (1UL << _PAGE_BIT_PROTNONE)
 103
 104#define _PAGE_TABLE     \
 105        ( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
 106        | _PAGE_DIRTY )
 107#define _KERNPG_TABLE   \
 108        ( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
 109        | _PAGE_DIRTY )
 110#define _PAGE_CHG_MASK  \
 111        ( PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY )
 112
 113#ifdef CONFIG_MMU
 114#define PAGE_NONE       \
 115        __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
 116#define PAGE_SHARED     \
 117        __pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED)
 118#define PAGE_SHARED_EXEC \
 119        __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ \
 120                | _PAGE_ACCESSED)
 121#define PAGE_COPY       \
 122        __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
 123#define PAGE_COPY_EXEC  \
 124        __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
 125#define PAGE_READONLY   \
 126        __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
 127#define PAGE_READONLY_EXEC \
 128        __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
 129
 130#define __PAGE_KERNEL   \
 131        ( _PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ | _PAGE_DIRTY \
 132        | _PAGE_ACCESSED )
 133#define __PAGE_KERNEL_RO        ( __PAGE_KERNEL & ~_PAGE_WRITE )
 134#define __PAGE_KERNEL_NOCACHE   ( __PAGE_KERNEL | _PAGE_NONCACHABLE)
 135
 136#define MAKE_GLOBAL(x)  __pgprot((x) | _PAGE_GLOBAL)
 137
 138#define PAGE_KERNEL             MAKE_GLOBAL(__PAGE_KERNEL)
 139#define PAGE_KERNEL_RO          MAKE_GLOBAL(__PAGE_KERNEL_RO)
 140#define PAGE_KERNEL_NOCACHE     MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
 141
 142#else
 143#define PAGE_NONE               __pgprot(0)
 144#define PAGE_SHARED             __pgprot(0)
 145#define PAGE_SHARED_EXEC        __pgprot(0)
 146#define PAGE_COPY               __pgprot(0)
 147#define PAGE_COPY_EXEC          __pgprot(0)
 148#define PAGE_READONLY           __pgprot(0)
 149#define PAGE_READONLY_EXEC      __pgprot(0)
 150
 151#define PAGE_KERNEL             __pgprot(0)
 152#define PAGE_KERNEL_RO          __pgprot(0)
 153#define PAGE_KERNEL_NOCACHE     __pgprot(0)
 154#endif /* CONFIG_MMU */
 155
 156        /* xwr */
 157#define __P000  PAGE_NONE
 158#define __P001  PAGE_READONLY
 159#define __P010  PAGE_COPY
 160#define __P011  PAGE_COPY
 161#define __P100  PAGE_READONLY_EXEC
 162#define __P101  PAGE_READONLY_EXEC
 163#define __P110  PAGE_COPY_EXEC
 164#define __P111  PAGE_COPY_EXEC
 165
 166#define __S000  PAGE_NONE
 167#define __S001  PAGE_READONLY
 168#define __S010  PAGE_SHARED
 169#define __S011  PAGE_SHARED
 170#define __S100  PAGE_READONLY_EXEC
 171#define __S101  PAGE_READONLY_EXEC
 172#define __S110  PAGE_SHARED_EXEC
 173#define __S111  PAGE_SHARED_EXEC
 174
 175/* page table for 0-4MB for everybody */
 176
 177#define pte_present(x)  (pte_val(x) & (_PAGE_PRESENT | _PAGE_PROTNONE))
 178#define pte_clear(mm,addr,xp)   do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
 179
 180#define pmd_none(x)     (!pmd_val(x))
 181#define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 182#define pmd_clear(xp)   do { set_pmd(xp, __pmd(0)); } while (0)
 183#define pmd_bad(x)      ((pmd_val(x) & ~PAGE_MASK) != _KERNPG_TABLE)
 184
 185#define pages_to_mb(x)  ((x) >> (20 - PAGE_SHIFT))
 186
 187/*
 188 * The following only work if pte_present() is true.
 189 * Undefined behaviour if not..
 190 */
 191static inline int pte_dirty(pte_t pte)
 192{
 193        return pte_val(pte) & _PAGE_DIRTY;
 194}
 195
 196static inline int pte_young(pte_t pte)
 197{
 198        return pte_val(pte) & _PAGE_ACCESSED;
 199}
 200
 201static inline int pte_write(pte_t pte)
 202{
 203        return pte_val(pte) & _PAGE_WRITE;
 204}
 205
 206static inline int pte_special(pte_t pte)
 207{
 208        return 0;
 209}
 210
 211static inline pte_t pte_mkclean(pte_t pte)
 212{
 213        pte_val(pte) &= ~_PAGE_DIRTY;
 214        return pte;
 215}
 216
 217static inline pte_t pte_mkold(pte_t pte)
 218{
 219        pte_val(pte) &= ~_PAGE_ACCESSED;
 220        return pte;
 221}
 222
 223static inline pte_t pte_wrprotect(pte_t pte)
 224{
 225        pte_val(pte) &= ~_PAGE_WRITE;
 226        return pte;
 227}
 228
 229static inline pte_t pte_mkdirty(pte_t pte)
 230{
 231        pte_val(pte) |= _PAGE_DIRTY;
 232        return pte;
 233}
 234
 235static inline pte_t pte_mkyoung(pte_t pte)
 236{
 237        pte_val(pte) |= _PAGE_ACCESSED;
 238        return pte;
 239}
 240
 241static inline pte_t pte_mkwrite(pte_t pte)
 242{
 243        pte_val(pte) |= _PAGE_WRITE;
 244        return pte;
 245}
 246
 247static inline pte_t pte_mkspecial(pte_t pte)
 248{
 249        return pte;
 250}
 251
 252static inline  int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
 253{
 254        return test_and_clear_bit(_PAGE_BIT_ACCESSED, ptep);
 255}
 256
 257static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 258{
 259        clear_bit(_PAGE_BIT_WRITE, ptep);
 260}
 261
 262/*
 263 * Macro and implementation to make a page protection as uncachable.
 264 */
 265static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 266{
 267        unsigned long prot = pgprot_val(_prot);
 268
 269        prot |= _PAGE_NONCACHABLE;
 270        return __pgprot(prot);
 271}
 272
 273#define pgprot_writecombine(prot) pgprot_noncached(prot)
 274
 275/*
 276 * Conversion functions: convert a page and protection to a page entry,
 277 * and a page entry and page directory to the page they refer to.
 278 */
 279#define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), pgprot)
 280
 281static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 282{
 283        set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) \
 284                | pgprot_val(newprot)));
 285
 286        return pte;
 287}
 288
 289/*
 290 * Conversion functions: convert a page and protection to a page entry,
 291 * and a page entry and page directory to the page they refer to.
 292 */
 293
 294static inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
 295{
 296        pmd_val(*pmdp) = (((unsigned long) ptep) & PAGE_MASK);
 297}
 298
 299#define pmd_page_vaddr(pmd)     \
 300        ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 301
 302#ifndef CONFIG_DISCONTIGMEM
 303#define pmd_page(pmd)   (mem_map + ((pmd_val(pmd) >> PAGE_SHIFT) - PFN_BASE))
 304#endif /* !CONFIG_DISCONTIGMEM */
 305
 306/* to find an entry in a page-table-directory. */
 307#define pgd_index(address)      \
 308        (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
 309
 310#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
 311
 312/* to find an entry in a kernel page-table-directory */
 313#define pgd_offset_k(address)   pgd_offset(&init_mm, address)
 314
 315#define pmd_index(address)      \
 316        (((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
 317
 318#define pte_index(address)      \
 319        (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 320#define pte_offset_kernel(dir, address) \
 321        ((pte_t *)pmd_page_vaddr(*(dir)) + pte_index(address))
 322#define pte_offset_map(dir, address)    \
 323        ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 324#define pte_unmap(pte)          do { } while (0)
 325
 326/* Encode and de-code a swap entry */
 327#define __swp_type(x)                   (((x).val >> 2) & 0x1f)
 328#define __swp_offset(x)                 ((x).val >> 10)
 329#define __swp_entry(type, offset)       \
 330        ((swp_entry_t) { ((type) << 2) | ((offset) << 10) })
 331#define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) })
 332#define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 333
 334#endif /* !__ASSEMBLY__ */
 335
 336/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
 337#define kern_addr_valid(addr)   (1)
 338
 339#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 340#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 341#define __HAVE_ARCH_PTEP_SET_WRPROTECT
 342#define __HAVE_ARCH_PTE_SAME
 343#include <asm-generic/pgtable.h>
 344
 345#endif /* __KERNEL__ */
 346
 347#endif /* _ASM_M32R_PGTABLE_H */
 348