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_PROTNONE  0x010   /* if the user mapped it with PROT_NONE;
  22                                   pte_present gives true */
  23
  24#ifdef CONFIG_3_LEVEL_PGTABLES
  25#include <asm/pgtable-3level.h>
  26#else
  27#include <asm/pgtable-2level.h>
  28#endif
  29
  30extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
  31
  32/* zero page used for uninitialized stuff */
  33extern unsigned long *empty_zero_page;
  34
  35#define pgtable_cache_init() do ; while (0)
  36
  37/* Just any arbitrary offset to the start of the vmalloc VM area: the
  38 * current 8MB value just means that there will be a 8MB "hole" after the
  39 * physical memory until the kernel virtual memory starts.  That means that
  40 * any out-of-bounds memory accesses will hopefully be caught.
  41 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
  42 * area for the same reason. ;)
  43 */
  44
  45extern unsigned long end_iomem;
  46
  47#define VMALLOC_OFFSET  (__va_space)
  48#define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
  49#define PKMAP_BASE ((FIXADDR_START - LAST_PKMAP * PAGE_SIZE) & PMD_MASK)
  50#ifdef CONFIG_HIGHMEM
  51# define VMALLOC_END    (PKMAP_BASE-2*PAGE_SIZE)
  52#else
  53# define VMALLOC_END    (FIXADDR_START-2*PAGE_SIZE)
  54#endif
  55#define MODULES_VADDR   VMALLOC_START
  56#define MODULES_END     VMALLOC_END
  57#define MODULES_LEN     (MODULES_VADDR - MODULES_END)
  58
  59#define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
  60#define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
  61#define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
  62#define __PAGE_KERNEL_EXEC                                              \
  63         (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  64#define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  65#define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
  66#define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  67#define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  68#define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  69#define PAGE_KERNEL_EXEC        __pgprot(__PAGE_KERNEL_EXEC)
  70
  71/*
  72 * The i386 can't do page protection for execute, and considers that the same
  73 * are read.
  74 * Also, write permissions imply read permissions. This is the closest we can
  75 * get..
  76 */
  77#define __P000  PAGE_NONE
  78#define __P001  PAGE_READONLY
  79#define __P010  PAGE_COPY
  80#define __P011  PAGE_COPY
  81#define __P100  PAGE_READONLY
  82#define __P101  PAGE_READONLY
  83#define __P110  PAGE_COPY
  84#define __P111  PAGE_COPY
  85
  86#define __S000  PAGE_NONE
  87#define __S001  PAGE_READONLY
  88#define __S010  PAGE_SHARED
  89#define __S011  PAGE_SHARED
  90#define __S100  PAGE_READONLY
  91#define __S101  PAGE_READONLY
  92#define __S110  PAGE_SHARED
  93#define __S111  PAGE_SHARED
  94
  95/*
  96 * ZERO_PAGE is a global shared page that is always zero: used
  97 * for zero-mapped memory areas etc..
  98 */
  99#define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
 100
 101#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
 102
 103#define pmd_none(x)     (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
 104#define pmd_bad(x)      ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 105
 106#define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 107#define pmd_clear(xp)   do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
 108
 109#define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
 110#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
 111
 112#define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
 113#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
 114
 115#define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
 116
 117#define pte_page(x) pfn_to_page(pte_pfn(x))
 118
 119#define pte_present(x)  pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
 120
 121/*
 122 * =================================
 123 * Flags checking section.
 124 * =================================
 125 */
 126
 127static inline int pte_none(pte_t pte)
 128{
 129        return pte_is_zero(pte);
 130}
 131
 132/*
 133 * The following only work if pte_present() is true.
 134 * Undefined behaviour if not..
 135 */
 136static inline int pte_read(pte_t pte)
 137{ 
 138        return((pte_get_bits(pte, _PAGE_USER)) &&
 139               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 140}
 141
 142static inline int pte_exec(pte_t pte){
 143        return((pte_get_bits(pte, _PAGE_USER)) &&
 144               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 145}
 146
 147static inline int pte_write(pte_t pte)
 148{
 149        return((pte_get_bits(pte, _PAGE_RW)) &&
 150               !(pte_get_bits(pte, _PAGE_PROTNONE)));
 151}
 152
 153static inline int pte_dirty(pte_t pte)
 154{
 155        return pte_get_bits(pte, _PAGE_DIRTY);
 156}
 157
 158static inline int pte_young(pte_t pte)
 159{
 160        return pte_get_bits(pte, _PAGE_ACCESSED);
 161}
 162
 163static inline int pte_newpage(pte_t pte)
 164{
 165        return pte_get_bits(pte, _PAGE_NEWPAGE);
 166}
 167
 168static inline int pte_newprot(pte_t pte)
 169{ 
 170        return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
 171}
 172
 173static inline int pte_special(pte_t pte)
 174{
 175        return 0;
 176}
 177
 178/*
 179 * =================================
 180 * Flags setting section.
 181 * =================================
 182 */
 183
 184static inline pte_t pte_mknewprot(pte_t pte)
 185{
 186        pte_set_bits(pte, _PAGE_NEWPROT);
 187        return(pte);
 188}
 189
 190static inline pte_t pte_mkclean(pte_t pte)
 191{
 192        pte_clear_bits(pte, _PAGE_DIRTY);
 193        return(pte);
 194}
 195
 196static inline pte_t pte_mkold(pte_t pte)        
 197{ 
 198        pte_clear_bits(pte, _PAGE_ACCESSED);
 199        return(pte);
 200}
 201
 202static inline pte_t pte_wrprotect(pte_t pte)
 203{ 
 204        pte_clear_bits(pte, _PAGE_RW);
 205        return(pte_mknewprot(pte)); 
 206}
 207
 208static inline pte_t pte_mkread(pte_t pte)
 209{ 
 210        pte_set_bits(pte, _PAGE_USER);
 211        return(pte_mknewprot(pte)); 
 212}
 213
 214static inline pte_t pte_mkdirty(pte_t pte)
 215{ 
 216        pte_set_bits(pte, _PAGE_DIRTY);
 217        return(pte);
 218}
 219
 220static inline pte_t pte_mkyoung(pte_t pte)
 221{
 222        pte_set_bits(pte, _PAGE_ACCESSED);
 223        return(pte);
 224}
 225
 226static inline pte_t pte_mkwrite(pte_t pte)      
 227{
 228        pte_set_bits(pte, _PAGE_RW);
 229        return(pte_mknewprot(pte)); 
 230}
 231
 232static inline pte_t pte_mkuptodate(pte_t pte)   
 233{
 234        pte_clear_bits(pte, _PAGE_NEWPAGE);
 235        if(pte_present(pte))
 236                pte_clear_bits(pte, _PAGE_NEWPROT);
 237        return(pte); 
 238}
 239
 240static inline pte_t pte_mknewpage(pte_t pte)
 241{
 242        pte_set_bits(pte, _PAGE_NEWPAGE);
 243        return(pte);
 244}
 245
 246static inline pte_t pte_mkspecial(pte_t pte)
 247{
 248        return(pte);
 249}
 250
 251static inline void set_pte(pte_t *pteptr, pte_t pteval)
 252{
 253        pte_copy(*pteptr, pteval);
 254
 255        /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
 256         * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
 257         * mapped pages.
 258         */
 259
 260        *pteptr = pte_mknewpage(*pteptr);
 261        if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
 262}
 263#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 264
 265#define __HAVE_ARCH_PTE_SAME
 266static inline int pte_same(pte_t pte_a, pte_t pte_b)
 267{
 268        return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
 269}
 270
 271/*
 272 * Conversion functions: convert a page and protection to a page entry,
 273 * and a page entry and page directory to the page they refer to.
 274 */
 275
 276#define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
 277#define __virt_to_page(virt) phys_to_page(__pa(virt))
 278#define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
 279#define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
 280
 281#define mk_pte(page, pgprot) \
 282        ({ pte_t pte;                                   \
 283                                                        \
 284        pte_set_val(pte, page_to_phys(page), (pgprot)); \
 285        if (pte_present(pte))                           \
 286                pte_mknewprot(pte_mknewpage(pte));      \
 287        pte;})
 288
 289static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 290{
 291        pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
 292        return pte; 
 293}
 294
 295/*
 296 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 297 *
 298 * this macro returns the index of the entry in the pgd page which would
 299 * control the given virtual address
 300 */
 301#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
 302
 303/*
 304 * pgd_offset() returns a (pgd_t *)
 305 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 306 */
 307#define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
 308
 309/*
 310 * a shortcut which implies the use of the kernel's pgd, instead
 311 * of a process's
 312 */
 313#define pgd_offset_k(address) pgd_offset(&init_mm, address)
 314
 315/*
 316 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
 317 *
 318 * this macro returns the index of the entry in the pmd page which would
 319 * control the given virtual address
 320 */
 321#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 322#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
 323
 324#define pmd_page_vaddr(pmd) \
 325        ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 326
 327/*
 328 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 329 *
 330 * this macro returns the index of the entry in the pte page which would
 331 * control the given virtual address
 332 */
 333#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 334#define pte_offset_kernel(dir, address) \
 335        ((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
 336#define pte_offset_map(dir, address) \
 337        ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 338#define pte_unmap(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,ptep) do ; while (0)
 344
 345/* Encode and de-code a swap entry */
 346#define __swp_type(x)                   (((x).val >> 5) & 0x1f)
 347#define __swp_offset(x)                 ((x).val >> 11)
 348
 349#define __swp_entry(type, offset) \
 350        ((swp_entry_t) { ((type) << 5) | ((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