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/*
  73 * The i386 can't do page protection for execute, and considers that the same
  74 * are read.
  75 * Also, write permissions imply read permissions. This is the closest we can
  76 * get..
  77 */
  78#define __P000  PAGE_NONE
  79#define __P001  PAGE_READONLY
  80#define __P010  PAGE_COPY
  81#define __P011  PAGE_COPY
  82#define __P100  PAGE_READONLY
  83#define __P101  PAGE_READONLY
  84#define __P110  PAGE_COPY
  85#define __P111  PAGE_COPY
  86
  87#define __S000  PAGE_NONE
  88#define __S001  PAGE_READONLY
  89#define __S010  PAGE_SHARED
  90#define __S011  PAGE_SHARED
  91#define __S100  PAGE_READONLY
  92#define __S101  PAGE_READONLY
  93#define __S110  PAGE_SHARED
  94#define __S111  PAGE_SHARED
  95
  96/*
  97 * ZERO_PAGE is a global shared page that is always zero: used
  98 * for zero-mapped memory areas etc..
  99 */
 100#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
 101
 102#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
 103
 104#define pmd_none(x)     (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
 105#define pmd_bad(x)      ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 106
 107#define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 108#define pmd_clear(xp)   do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
 109
 110#define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
 111#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
 112
 113#define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
 114#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
 115
 116#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
 117
 118#define pte_page(x) pfn_to_page(pte_pfn(x))
 119
 120#define pte_present(x)  pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
 121
 122/*
 123 * =================================
 124 * Flags checking section.
 125 * =================================
 126 */
 127
 128static inline int pte_none(pte_t pte)
 129{
 130        return pte_is_zero(pte);
 131}
 132
 133/*
 134 * The following only work if pte_present() is true.
 135 * Undefined behaviour if not..
 136 */
 137static inline int pte_read(pte_t pte)
 138{ 
 139        return((pte_get_bits(pte, _PAGE_USER)) &&
 140               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 141}
 142
 143static inline int pte_exec(pte_t pte){
 144        return((pte_get_bits(pte, _PAGE_USER)) &&
 145               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 146}
 147
 148static inline int pte_write(pte_t pte)
 149{
 150        return((pte_get_bits(pte, _PAGE_RW)) &&
 151               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 152}
 153
 154/*
 155 * The following only works if pte_present() is not true.
 156 */
 157static inline int pte_file(pte_t pte)
 158{
 159        return pte_get_bits(pte, _PAGE_FILE);
 160}
 161
 162static inline int pte_dirty(pte_t pte)
 163{
 164        return pte_get_bits(pte, _PAGE_DIRTY);
 165}
 166
 167static inline int pte_young(pte_t pte)
 168{
 169        return pte_get_bits(pte, _PAGE_ACCESSED);
 170}
 171
 172static inline int pte_newpage(pte_t pte)
 173{
 174        return pte_get_bits(pte, _PAGE_NEWPAGE);
 175}
 176
 177static inline int pte_newprot(pte_t pte)
 178{ 
 179        return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
 180}
 181
 182static inline int pte_special(pte_t pte)
 183{
 184        return 0;
 185}
 186
 187/*
 188 * =================================
 189 * Flags setting section.
 190 * =================================
 191 */
 192
 193static inline pte_t pte_mknewprot(pte_t pte)
 194{
 195        pte_set_bits(pte, _PAGE_NEWPROT);
 196        return(pte);
 197}
 198
 199static inline pte_t pte_mkclean(pte_t pte)
 200{
 201        pte_clear_bits(pte, _PAGE_DIRTY);
 202        return(pte);
 203}
 204
 205static inline pte_t pte_mkold(pte_t pte)        
 206{ 
 207        pte_clear_bits(pte, _PAGE_ACCESSED);
 208        return(pte);
 209}
 210
 211static inline pte_t pte_wrprotect(pte_t pte)
 212{ 
 213        pte_clear_bits(pte, _PAGE_RW);
 214        return(pte_mknewprot(pte)); 
 215}
 216
 217static inline pte_t pte_mkread(pte_t pte)
 218{ 
 219        pte_set_bits(pte, _PAGE_USER);
 220        return(pte_mknewprot(pte)); 
 221}
 222
 223static inline pte_t pte_mkdirty(pte_t pte)
 224{ 
 225        pte_set_bits(pte, _PAGE_DIRTY);
 226        return(pte);
 227}
 228
 229static inline pte_t pte_mkyoung(pte_t pte)
 230{
 231        pte_set_bits(pte, _PAGE_ACCESSED);
 232        return(pte);
 233}
 234
 235static inline pte_t pte_mkwrite(pte_t pte)      
 236{
 237        pte_set_bits(pte, _PAGE_RW);
 238        return(pte_mknewprot(pte)); 
 239}
 240
 241static inline pte_t pte_mkuptodate(pte_t pte)   
 242{
 243        pte_clear_bits(pte, _PAGE_NEWPAGE);
 244        if(pte_present(pte))
 245                pte_clear_bits(pte, _PAGE_NEWPROT);
 246        return(pte); 
 247}
 248
 249static inline pte_t pte_mknewpage(pte_t pte)
 250{
 251        pte_set_bits(pte, _PAGE_NEWPAGE);
 252        return(pte);
 253}
 254
 255static inline pte_t pte_mkspecial(pte_t pte)
 256{
 257        return(pte);
 258}
 259
 260static inline void set_pte(pte_t *pteptr, pte_t pteval)
 261{
 262        pte_copy(*pteptr, pteval);
 263
 264        /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
 265         * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
 266         * mapped pages.
 267         */
 268
 269        *pteptr = pte_mknewpage(*pteptr);
 270        if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
 271}
 272#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 273
 274/*
 275 * Conversion functions: convert a page and protection to a page entry,
 276 * and a page entry and page directory to the page they refer to.
 277 */
 278
 279#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
 280#define __virt_to_page(virt) phys_to_page(__pa(virt))
 281#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
 282#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
 283
 284#define mk_pte(page, pgprot) \
 285        ({ pte_t pte;                                   \
 286                                                        \
 287        pte_set_val(pte, page_to_phys(page), (pgprot)); \
 288        if (pte_present(pte))                           \
 289                pte_mknewprot(pte_mknewpage(pte));      \
 290        pte;})
 291
 292static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 293{
 294        pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
 295        return pte; 
 296}
 297
 298/*
 299 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 300 *
 301 * this macro returns the index of the entry in the pgd page which would
 302 * control the given virtual address
 303 */
 304#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
 305
 306/*
 307 * pgd_offset() returns a (pgd_t *)
 308 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 309 */
 310#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
 311
 312/*
 313 * a shortcut which implies the use of the kernel's pgd, instead
 314 * of a process's
 315 */
 316#define pgd_offset_k(address) pgd_offset(&init_mm, address)
 317
 318/*
 319 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
 320 *
 321 * this macro returns the index of the entry in the pmd page which would
 322 * control the given virtual address
 323 */
 324#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 325#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
 326
 327#define pmd_page_vaddr(pmd) \
 328        ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 329
 330/*
 331 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 332 *
 333 * this macro returns the index of the entry in the pte page which would
 334 * control the given virtual address
 335 */
 336#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 337#define pte_offset_kernel(dir, address) \
 338        ((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
 339#define pte_offset_map(dir, address) \
 340        ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 341#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
 342#define pte_unmap(pte) do { } while (0)
 343#define pte_unmap_nested(pte) do { } while (0)
 344
 345struct mm_struct;
 346extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
 347
 348#define update_mmu_cache(vma,address,pte) do ; while (0)
 349
 350/* Encode and de-code a swap entry */
 351#define __swp_type(x)                   (((x).val >> 4) & 0x3f)
 352#define __swp_offset(x)                 ((x).val >> 11)
 353
 354#define __swp_entry(type, offset) \
 355        ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
 356#define __pte_to_swp_entry(pte) \
 357        ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
 358#define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 359
 360#define kern_addr_valid(addr) (1)
 361
 362#include <asm-generic/pgtable.h>
 363
 364/* Clear a kernel PTE and flush it from the TLB */
 365#define kpte_clear_flush(ptep, vaddr)           \
 366do {                                            \
 367        pte_clear(&init_mm, (vaddr), (ptep));   \
 368        __flush_tlb_one((vaddr));               \
 369} while (0)
 370
 371#endif
 372