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#define MODULES_VADDR   VMALLOC_START
  57#define MODULES_END     VMALLOC_END
  58#define MODULES_LEN     (MODULES_VADDR - MODULES_END)
  59
  60#define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
  61#define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
  62#define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
  63#define __PAGE_KERNEL_EXEC                                              \
  64         (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  65#define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  66#define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
  67#define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  68#define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  69#define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  70#define PAGE_KERNEL_EXEC        __pgprot(__PAGE_KERNEL_EXEC)
  71
  72#define io_remap_pfn_range      remap_pfn_range
  73
  74/*
  75 * The i386 can't do page protection for execute, and considers that the same
  76 * are read.
  77 * Also, write permissions imply read permissions. This is the closest we can
  78 * get..
  79 */
  80#define __P000  PAGE_NONE
  81#define __P001  PAGE_READONLY
  82#define __P010  PAGE_COPY
  83#define __P011  PAGE_COPY
  84#define __P100  PAGE_READONLY
  85#define __P101  PAGE_READONLY
  86#define __P110  PAGE_COPY
  87#define __P111  PAGE_COPY
  88
  89#define __S000  PAGE_NONE
  90#define __S001  PAGE_READONLY
  91#define __S010  PAGE_SHARED
  92#define __S011  PAGE_SHARED
  93#define __S100  PAGE_READONLY
  94#define __S101  PAGE_READONLY
  95#define __S110  PAGE_SHARED
  96#define __S111  PAGE_SHARED
  97
  98/*
  99 * ZERO_PAGE is a global shared page that is always zero: used
 100 * for zero-mapped memory areas etc..
 101 */
 102#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
 103
 104#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
 105
 106#define pmd_none(x)     (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
 107#define pmd_bad(x)      ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 108
 109#define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 110#define pmd_clear(xp)   do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
 111
 112#define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
 113#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
 114
 115#define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
 116#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
 117
 118#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
 119
 120#define pte_page(x) pfn_to_page(pte_pfn(x))
 121
 122#define pte_present(x)  pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
 123
 124/*
 125 * =================================
 126 * Flags checking section.
 127 * =================================
 128 */
 129
 130static inline int pte_none(pte_t pte)
 131{
 132        return pte_is_zero(pte);
 133}
 134
 135/*
 136 * The following only work if pte_present() is true.
 137 * Undefined behaviour if not..
 138 */
 139static inline int pte_read(pte_t pte)
 140{ 
 141        return((pte_get_bits(pte, _PAGE_USER)) &&
 142               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 143}
 144
 145static inline int pte_exec(pte_t pte){
 146        return((pte_get_bits(pte, _PAGE_USER)) &&
 147               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 148}
 149
 150static inline int pte_write(pte_t pte)
 151{
 152        return((pte_get_bits(pte, _PAGE_RW)) &&
 153               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 154}
 155
 156/*
 157 * The following only works if pte_present() is not true.
 158 */
 159static inline int pte_file(pte_t pte)
 160{
 161        return pte_get_bits(pte, _PAGE_FILE);
 162}
 163
 164static inline int pte_dirty(pte_t pte)
 165{
 166        return pte_get_bits(pte, _PAGE_DIRTY);
 167}
 168
 169static inline int pte_young(pte_t pte)
 170{
 171        return pte_get_bits(pte, _PAGE_ACCESSED);
 172}
 173
 174static inline int pte_newpage(pte_t pte)
 175{
 176        return pte_get_bits(pte, _PAGE_NEWPAGE);
 177}
 178
 179static inline int pte_newprot(pte_t pte)
 180{ 
 181        return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
 182}
 183
 184static inline int pte_special(pte_t pte)
 185{
 186        return 0;
 187}
 188
 189/*
 190 * =================================
 191 * Flags setting section.
 192 * =================================
 193 */
 194
 195static inline pte_t pte_mknewprot(pte_t pte)
 196{
 197        pte_set_bits(pte, _PAGE_NEWPROT);
 198        return(pte);
 199}
 200
 201static inline pte_t pte_mkclean(pte_t pte)
 202{
 203        pte_clear_bits(pte, _PAGE_DIRTY);
 204        return(pte);
 205}
 206
 207static inline pte_t pte_mkold(pte_t pte)        
 208{ 
 209        pte_clear_bits(pte, _PAGE_ACCESSED);
 210        return(pte);
 211}
 212
 213static inline pte_t pte_wrprotect(pte_t pte)
 214{ 
 215        pte_clear_bits(pte, _PAGE_RW);
 216        return(pte_mknewprot(pte)); 
 217}
 218
 219static inline pte_t pte_mkread(pte_t pte)
 220{ 
 221        pte_set_bits(pte, _PAGE_USER);
 222        return(pte_mknewprot(pte)); 
 223}
 224
 225static inline pte_t pte_mkdirty(pte_t pte)
 226{ 
 227        pte_set_bits(pte, _PAGE_DIRTY);
 228        return(pte);
 229}
 230
 231static inline pte_t pte_mkyoung(pte_t pte)
 232{
 233        pte_set_bits(pte, _PAGE_ACCESSED);
 234        return(pte);
 235}
 236
 237static inline pte_t pte_mkwrite(pte_t pte)      
 238{
 239        pte_set_bits(pte, _PAGE_RW);
 240        return(pte_mknewprot(pte)); 
 241}
 242
 243static inline pte_t pte_mkuptodate(pte_t pte)   
 244{
 245        pte_clear_bits(pte, _PAGE_NEWPAGE);
 246        if(pte_present(pte))
 247                pte_clear_bits(pte, _PAGE_NEWPROT);
 248        return(pte); 
 249}
 250
 251static inline pte_t pte_mknewpage(pte_t pte)
 252{
 253        pte_set_bits(pte, _PAGE_NEWPAGE);
 254        return(pte);
 255}
 256
 257static inline pte_t pte_mkspecial(pte_t pte)
 258{
 259        return(pte);
 260}
 261
 262static inline void set_pte(pte_t *pteptr, pte_t pteval)
 263{
 264        pte_copy(*pteptr, pteval);
 265
 266        /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
 267         * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
 268         * mapped pages.
 269         */
 270
 271        *pteptr = pte_mknewpage(*pteptr);
 272        if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
 273}
 274#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 275
 276#define __HAVE_ARCH_PTE_SAME
 277static inline int pte_same(pte_t pte_a, pte_t pte_b)
 278{
 279        return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
 280}
 281
 282/*
 283 * Conversion functions: convert a page and protection to a page entry,
 284 * and a page entry and page directory to the page they refer to.
 285 */
 286
 287#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
 288#define __virt_to_page(virt) phys_to_page(__pa(virt))
 289#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
 290#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
 291
 292#define mk_pte(page, pgprot) \
 293        ({ pte_t pte;                                   \
 294                                                        \
 295        pte_set_val(pte, page_to_phys(page), (pgprot)); \
 296        if (pte_present(pte))                           \
 297                pte_mknewprot(pte_mknewpage(pte));      \
 298        pte;})
 299
 300static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 301{
 302        pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
 303        return pte; 
 304}
 305
 306/*
 307 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 308 *
 309 * this macro returns the index of the entry in the pgd page which would
 310 * control the given virtual address
 311 */
 312#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
 313
 314/*
 315 * pgd_offset() returns a (pgd_t *)
 316 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 317 */
 318#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
 319
 320/*
 321 * a shortcut which implies the use of the kernel's pgd, instead
 322 * of a process's
 323 */
 324#define pgd_offset_k(address) pgd_offset(&init_mm, address)
 325
 326/*
 327 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
 328 *
 329 * this macro returns the index of the entry in the pmd page which would
 330 * control the given virtual address
 331 */
 332#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 333#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
 334
 335#define pmd_page_vaddr(pmd) \
 336        ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 337
 338/*
 339 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 340 *
 341 * this macro returns the index of the entry in the pte page which would
 342 * control the given virtual address
 343 */
 344#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 345#define pte_offset_kernel(dir, address) \
 346        ((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
 347#define pte_offset_map(dir, address) \
 348        ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 349#define pte_unmap(pte) do { } while (0)
 350
 351struct mm_struct;
 352extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
 353
 354#define update_mmu_cache(vma,address,ptep) do ; while (0)
 355
 356/* Encode and de-code a swap entry */
 357#define __swp_type(x)                   (((x).val >> 5) & 0x1f)
 358#define __swp_offset(x)                 ((x).val >> 11)
 359
 360#define __swp_entry(type, offset) \
 361        ((swp_entry_t) { ((type) << 5) | ((offset) << 11) })
 362#define __pte_to_swp_entry(pte) \
 363        ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
 364#define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 365
 366#define kern_addr_valid(addr) (1)
 367
 368#include <asm-generic/pgtable.h>
 369
 370/* Clear a kernel PTE and flush it from the TLB */
 371#define kpte_clear_flush(ptep, vaddr)           \
 372do {                                            \
 373        pte_clear(&init_mm, (vaddr), (ptep));   \
 374        __flush_tlb_one((vaddr));               \
 375} while (0)
 376
 377#endif
 378