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

   1/* 
   2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   3 * Copyright 2003 PathScale, Inc.
   4 * Derived from include/asm-i386/pgtable.h
   5 * Licensed under the GPL
   6 */
   7
   8#ifndef __UM_PGTABLE_H
   9#define __UM_PGTABLE_H
  10
  11#include <asm/fixmap.h>
  12
  13#define _PAGE_PRESENT   0x001
  14#define _PAGE_NEWPAGE   0x002
  15#define _PAGE_NEWPROT   0x004
  16#define _PAGE_RW        0x020
  17#define _PAGE_USER      0x040
  18#define _PAGE_ACCESSED  0x080
  19#define _PAGE_DIRTY     0x100
  20/* If _PAGE_PRESENT is clear, we use these: */
  21#define _PAGE_FILE      0x008   /* nonlinear file mapping, saved PTE; unset:swap */
  22#define _PAGE_PROTNONE  0x010   /* if the user mapped it with PROT_NONE;
  23                                   pte_present gives true */
  24
  25#ifdef CONFIG_3_LEVEL_PGTABLES
  26#include "asm/pgtable-3level.h"
  27#else
  28#include "asm/pgtable-2level.h"
  29#endif
  30
  31extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
  32
  33/* zero page used for uninitialized stuff */
  34extern unsigned long *empty_zero_page;
  35
  36#define pgtable_cache_init() do ; while (0)
  37
  38/* Just any arbitrary offset to the start of the vmalloc VM area: the
  39 * current 8MB value just means that there will be a 8MB "hole" after the
  40 * physical memory until the kernel virtual memory starts.  That means that
  41 * any out-of-bounds memory accesses will hopefully be caught.
  42 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  43 * area for the same reason. ;)
  44 */
  45
  46extern unsigned long end_iomem;
  47
  48#define VMALLOC_OFFSET  (__va_space)
  49#define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
  50#define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
  51#ifdef CONFIG_HIGHMEM
  52# define VMALLOC_END    (PKMAP_BASE-2*PAGE_SIZE)
  53#else
  54# define VMALLOC_END    (FIXADDR_START-2*PAGE_SIZE)
  55#endif
  56
  57#define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
  58#define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
  59#define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
  60
  61#define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  62#define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
  63#define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  64#define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  65#define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  66
  67/*
  68 * The i386 can't do page protection for execute, and considers that the same
  69 * are read.
  70 * Also, write permissions imply read permissions. This is the closest we can
  71 * get..
  72 */
  73#define __P000  PAGE_NONE
  74#define __P001  PAGE_READONLY
  75#define __P010  PAGE_COPY
  76#define __P011  PAGE_COPY
  77#define __P100  PAGE_READONLY
  78#define __P101  PAGE_READONLY
  79#define __P110  PAGE_COPY
  80#define __P111  PAGE_COPY
  81
  82#define __S000  PAGE_NONE
  83#define __S001  PAGE_READONLY
  84#define __S010  PAGE_SHARED
  85#define __S011  PAGE_SHARED
  86#define __S100  PAGE_READONLY
  87#define __S101  PAGE_READONLY
  88#define __S110  PAGE_SHARED
  89#define __S111  PAGE_SHARED
  90
  91/*
  92 * ZERO_PAGE is a global shared page that is always zero: used
  93 * for zero-mapped memory areas etc..
  94 */
  95#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
  96
  97#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
  98
  99#define pmd_none(x)     (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
 100#define pmd_bad(x)      ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 101
 102#define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 103#define pmd_clear(xp)   do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
 104
 105#define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
 106#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
 107
 108#define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
 109#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
 110
 111#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
 112
 113#define pte_page(x) pfn_to_page(pte_pfn(x))
 114
 115#define pte_present(x)  pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
 116
 117/*
 118 * =================================
 119 * Flags checking section.
 120 * =================================
 121 */
 122
 123static inline int pte_none(pte_t pte)
 124{
 125        return pte_is_zero(pte);
 126}
 127
 128/*
 129 * The following only work if pte_present() is true.
 130 * Undefined behaviour if not..
 131 */
 132static inline int pte_read(pte_t pte)
 133{ 
 134        return((pte_get_bits(pte, _PAGE_USER)) &&
 135               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 136}
 137
 138static inline int pte_exec(pte_t pte){
 139        return((pte_get_bits(pte, _PAGE_USER)) &&
 140               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 141}
 142
 143static inline int pte_write(pte_t pte)
 144{
 145        return((pte_get_bits(pte, _PAGE_RW)) &&
 146               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 147}
 148
 149/*
 150 * The following only works if pte_present() is not true.
 151 */
 152static inline int pte_file(pte_t pte)
 153{
 154        return pte_get_bits(pte, _PAGE_FILE);
 155}
 156
 157static inline int pte_dirty(pte_t pte)
 158{
 159        return pte_get_bits(pte, _PAGE_DIRTY);
 160}
 161
 162static inline int pte_young(pte_t pte)
 163{
 164        return pte_get_bits(pte, _PAGE_ACCESSED);
 165}
 166
 167static inline int pte_newpage(pte_t pte)
 168{
 169        return pte_get_bits(pte, _PAGE_NEWPAGE);
 170}
 171
 172static inline int pte_newprot(pte_t pte)
 173{ 
 174        return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
 175}
 176
 177static inline int pte_special(pte_t pte)
 178{
 179        return 0;
 180}
 181
 182/*
 183 * =================================
 184 * Flags setting section.
 185 * =================================
 186 */
 187
 188static inline pte_t pte_mknewprot(pte_t pte)
 189{
 190        pte_set_bits(pte, _PAGE_NEWPROT);
 191        return(pte);
 192}
 193
 194static inline pte_t pte_mkclean(pte_t pte)
 195{
 196        pte_clear_bits(pte, _PAGE_DIRTY);
 197        return(pte);
 198}
 199
 200static inline pte_t pte_mkold(pte_t pte)        
 201{ 
 202        pte_clear_bits(pte, _PAGE_ACCESSED);
 203        return(pte);
 204}
 205
 206static inline pte_t pte_wrprotect(pte_t pte)
 207{ 
 208        pte_clear_bits(pte, _PAGE_RW);
 209        return(pte_mknewprot(pte)); 
 210}
 211
 212static inline pte_t pte_mkread(pte_t pte)
 213{ 
 214        pte_set_bits(pte, _PAGE_USER);
 215        return(pte_mknewprot(pte)); 
 216}
 217
 218static inline pte_t pte_mkdirty(pte_t pte)
 219{ 
 220        pte_set_bits(pte, _PAGE_DIRTY);
 221        return(pte);
 222}
 223
 224static inline pte_t pte_mkyoung(pte_t pte)
 225{
 226        pte_set_bits(pte, _PAGE_ACCESSED);
 227        return(pte);
 228}
 229
 230static inline pte_t pte_mkwrite(pte_t pte)      
 231{
 232        pte_set_bits(pte, _PAGE_RW);
 233        return(pte_mknewprot(pte)); 
 234}
 235
 236static inline pte_t pte_mkuptodate(pte_t pte)   
 237{
 238        pte_clear_bits(pte, _PAGE_NEWPAGE);
 239        if(pte_present(pte))
 240                pte_clear_bits(pte, _PAGE_NEWPROT);
 241        return(pte); 
 242}
 243
 244static inline pte_t pte_mknewpage(pte_t pte)
 245{
 246        pte_set_bits(pte, _PAGE_NEWPAGE);
 247        return(pte);
 248}
 249
 250static inline pte_t pte_mkspecial(pte_t pte)
 251{
 252        return(pte);
 253}
 254
 255static inline void set_pte(pte_t *pteptr, pte_t pteval)
 256{
 257        pte_copy(*pteptr, pteval);
 258
 259        /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
 260         * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
 261         * mapped pages.
 262         */
 263
 264        *pteptr = pte_mknewpage(*pteptr);
 265        if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
 266}
 267#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 268
 269/*
 270 * Conversion functions: convert a page and protection to a page entry,
 271 * and a page entry and page directory to the page they refer to.
 272 */
 273
 274#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
 275#define __virt_to_page(virt) phys_to_page(__pa(virt))
 276#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
 277#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
 278
 279#define mk_pte(page, pgprot) \
 280        ({ pte_t pte;                                   \
 281                                                        \
 282        pte_set_val(pte, page_to_phys(page), (pgprot)); \
 283        if (pte_present(pte))                           \
 284                pte_mknewprot(pte_mknewpage(pte));      \
 285        pte;})
 286
 287static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 288{
 289        pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
 290        return pte; 
 291}
 292
 293/*
 294 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 295 *
 296 * this macro returns the index of the entry in the pgd page which would
 297 * control the given virtual address
 298 */
 299#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
 300
 301/*
 302 * pgd_offset() returns a (pgd_t *)
 303 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 304 */
 305#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
 306
 307/*
 308 * a shortcut which implies the use of the kernel's pgd, instead
 309 * of a process's
 310 */
 311#define pgd_offset_k(address) pgd_offset(&init_mm, address)
 312
 313/*
 314 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
 315 *
 316 * this macro returns the index of the entry in the pmd page which would
 317 * control the given virtual address
 318 */
 319#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 320#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
 321
 322#define pmd_page_vaddr(pmd) \
 323        ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 324
 325/*
 326 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 327 *
 328 * this macro returns the index of the entry in the pte page which would
 329 * control the given virtual address
 330 */
 331#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 332#define pte_offset_kernel(dir, address) \
 333        ((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
 334#define pte_offset_map(dir, address) \
 335        ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 336#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
 337#define pte_unmap(pte) do { } while (0)
 338#define pte_unmap_nested(pte) do { } while (0)
 339
 340struct mm_struct;
 341extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
 342
 343#define update_mmu_cache(vma,address,pte) do ; while (0)
 344
 345/* Encode and de-code a swap entry */
 346#define __swp_type(x)                   (((x).val >> 4) & 0x3f)
 347#define __swp_offset(x)                 ((x).val >> 11)
 348
 349#define __swp_entry(type, offset) \
 350        ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
 351#define __pte_to_swp_entry(pte) \
 352        ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
 353#define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 354
 355#define kern_addr_valid(addr) (1)
 356
 357#include <asm-generic/pgtable.h>
 358
 359/* Clear a kernel PTE and flush it from the TLB */
 360#define kpte_clear_flush(ptep, vaddr)           \
 361do {                                            \
 362        pte_clear(&init_mm, (vaddr), (ptep));   \
 363        __flush_tlb_one((vaddr));               \
 364} while (0)
 365
 366#endif
 367