include/asm-um/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
  31 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
  32
  33 /* zero page used for uninitialized stuff */
  34 extern 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
  46 extern unsigned long end_iomem;
  47
  48 #define VMALLOC_OFFSET  (__va_space)
  49 #define VMALLOC_START ((end_iomem + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
  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
  56 #define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
  57 #define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
  58 #define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
  59
  60 #define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  61 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
  62 #define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  63 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
  64 #define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  65
  66 /*
  67  * The i386 can't do page protection for execute, and considers that the same
  68  * are read.
  69  * Also, write permissions imply read permissions. This is the closest we can
  70  * get..
  71  */
  72 #define __P000  PAGE_NONE
  73 #define __P001  PAGE_READONLY
  74 #define __P010  PAGE_COPY
  75 #define __P011  PAGE_COPY
  76 #define __P100  PAGE_READONLY
  77 #define __P101  PAGE_READONLY
  78 #define __P110  PAGE_COPY
  79 #define __P111  PAGE_COPY
  80
  81 #define __S000  PAGE_NONE
  82 #define __S001  PAGE_READONLY
  83 #define __S010  PAGE_SHARED
  84 #define __S011  PAGE_SHARED
  85 #define __S100  PAGE_READONLY
  86 #define __S101  PAGE_READONLY
  87 #define __S110  PAGE_SHARED
  88 #define __S111  PAGE_SHARED
  89
  90 /*
  91  * ZERO_PAGE is a global shared page that is always zero: used
  92  * for zero-mapped memory areas etc..
  93  */
  94 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
  95
  96 #define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
  97
  98 #define pmd_none(x)     (!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
  99 #define pmd_bad(x)      ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 100
 101 #define pmd_present(x)  (pmd_val(x) & _PAGE_PRESENT)
 102 #define pmd_clear(xp)   do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
 103
 104 #define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
 105 #define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
 106
 107 #define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
 108 #define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
 109
 110 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
 111
 112 #define pte_page(x) pfn_to_page(pte_pfn(x))
 113
 114 #define pte_present(x)  pte_get_bits(x, (_PAGE_PRESENT | _PAGE_PROTNONE))
 115
 116 /*
 117  * =================================
 118  * Flags checking section.
 119  * =================================
 120  */
 121
 122 static inline int pte_none(pte_t pte)
 123 {
 124         return pte_is_zero(pte);
 125 }
 126
 127 /*
 128  * The following only work if pte_present() is true.
 129  * Undefined behaviour if not..
 130  */
 131 static inline int pte_read(pte_t pte)
 132 {
 133         return((pte_get_bits(pte, _PAGE_USER)) &&
 134                !(pte_get_bits(pte, _PAGE_PROTNONE)));
 135 }
 136
 137 static inline int pte_exec(pte_t pte){
 138         return((pte_get_bits(pte, _PAGE_USER)) &&
 139                !(pte_get_bits(pte, _PAGE_PROTNONE)));
 140 }
 141
 142 static inline int pte_write(pte_t pte)
 143 {
 144         return((pte_get_bits(pte, _PAGE_RW)) &&
 145                !(pte_get_bits(pte, _PAGE_PROTNONE)));
 146 }
 147
 148 /*
 149  * The following only works if pte_present() is not true.
 150  */
 151 static inline int pte_file(pte_t pte)
 152 {
 153         return pte_get_bits(pte, _PAGE_FILE);
 154 }
 155
 156 static inline int pte_dirty(pte_t pte)
 157 {
 158         return pte_get_bits(pte, _PAGE_DIRTY);
 159 }
 160
 161 static inline int pte_young(pte_t pte)
 162 {
 163         return pte_get_bits(pte, _PAGE_ACCESSED);
 164 }
 165
 166 static inline int pte_newpage(pte_t pte)
 167 {
 168         return pte_get_bits(pte, _PAGE_NEWPAGE);
 169 }
 170
 171 static inline int pte_newprot(pte_t pte)
 172 {
 173         return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
 174 }
 175
 176 /*
 177  * =================================
 178  * Flags setting section.
 179  * =================================
 180  */
 181
 182 static inline pte_t pte_mknewprot(pte_t pte)
 183 {
 184         pte_set_bits(pte, _PAGE_NEWPROT);
 185         return(pte);
 186 }
 187
 188 static inline pte_t pte_mkclean(pte_t pte)
 189 {
 190         pte_clear_bits(pte, _PAGE_DIRTY);
 191         return(pte);
 192 }
 193
 194 static inline pte_t pte_mkold(pte_t pte)
 195 {
 196         pte_clear_bits(pte, _PAGE_ACCESSED);
 197         return(pte);
 198 }
 199
 200 static inline pte_t pte_wrprotect(pte_t pte)
 201 {
 202         pte_clear_bits(pte, _PAGE_RW);
 203         return(pte_mknewprot(pte));
 204 }
 205
 206 static inline pte_t pte_mkread(pte_t pte)
 207 {
 208         pte_set_bits(pte, _PAGE_USER);
 209         return(pte_mknewprot(pte));
 210 }
 211
 212 static inline pte_t pte_mkdirty(pte_t pte)
 213 {
 214         pte_set_bits(pte, _PAGE_DIRTY);
 215         return(pte);
 216 }
 217
 218 static inline pte_t pte_mkyoung(pte_t pte)
 219 {
 220         pte_set_bits(pte, _PAGE_ACCESSED);
 221         return(pte);
 222 }
 223
 224 static inline pte_t pte_mkwrite(pte_t pte)
 225 {
 226         pte_set_bits(pte, _PAGE_RW);
 227         return(pte_mknewprot(pte));
 228 }
 229
 230 static inline pte_t pte_mkuptodate(pte_t pte)
 231 {
 232         pte_clear_bits(pte, _PAGE_NEWPAGE);
 233         if(pte_present(pte))
 234                 pte_clear_bits(pte, _PAGE_NEWPROT);
 235         return(pte);
 236 }
 237
 238 static inline pte_t pte_mknewpage(pte_t pte)
 239 {
 240         pte_set_bits(pte, _PAGE_NEWPAGE);
 241         return(pte);
 242 }
 243
 244 static inline void set_pte(pte_t *pteptr, pte_t pteval)
 245 {
 246         pte_copy(*pteptr, pteval);
 247
 248         /* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
 249          * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
 250          * mapped pages.
 251          */
 252
 253         *pteptr = pte_mknewpage(*pteptr);
 254         if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
 255 }
 256 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
 257
 258 /*
 259  * Conversion functions: convert a page and protection to a page entry,
 260  * and a page entry and page directory to the page they refer to.
 261  */
 262
 263 #define phys_to_page(phys) pfn_to_page(phys_to_pfn(phys))
 264 #define __virt_to_page(virt) phys_to_page(__pa(virt))
 265 #define page_to_phys(page) pfn_to_phys((pfn_t) page_to_pfn(page))
 266 #define virt_to_page(addr) __virt_to_page((const unsigned long) addr)
 267
 268 #define mk_pte(page, pgprot) \
 269         ({ pte_t pte;                                   \
 270                                                         \
 271         pte_set_val(pte, page_to_phys(page), (pgprot)); \
 272         if (pte_present(pte))                           \
 273                 pte_mknewprot(pte_mknewpage(pte));      \
 274         pte;})
 275
 276 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 277 {
 278         pte_set_val(pte, (pte_val(pte) & _PAGE_CHG_MASK), newprot);
 279         return pte;
 280 }
 281
 282 /*
 283  * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 284  *
 285  * this macro returns the index of the entry in the pgd page which would
 286  * control the given virtual address
 287  */
 288 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
 289
 290 /*
 291  * pgd_offset() returns a (pgd_t *)
 292  * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 293  */
 294 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
 295
 296 /*
 297  * a shortcut which implies the use of the kernel's pgd, instead
 298  * of a process's
 299  */
 300 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
 301
 302 /*
 303  * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
 304  *
 305  * this macro returns the index of the entry in the pmd page which would
 306  * control the given virtual address
 307  */
 308 #define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
 309 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
 310
 311 /*
 312  * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 313  *
 314  * this macro returns the index of the entry in the pte page which would
 315  * control the given virtual address
 316  */
 317 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 318 #define pte_offset_kernel(dir, address) \
 319         ((pte_t *) pmd_page_vaddr(*(dir)) +  pte_index(address))
 320 #define pte_offset_map(dir, address) \
 321         ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
 322 #define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
 323 #define pte_unmap(pte) do { } while (0)
 324 #define pte_unmap_nested(pte) do { } while (0)
 325
 326 struct mm_struct;
 327 extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
 328
 329 #define update_mmu_cache(vma,address,pte) do ; while (0)
 330
 331 /* Encode and de-code a swap entry */
 332 #define __swp_type(x)                   (((x).val >> 4) & 0x3f)
 333 #define __swp_offset(x)                 ((x).val >> 11)
 334
 335 #define __swp_entry(type, offset) \
 336         ((swp_entry_t) { ((type) << 4) | ((offset) << 11) })
 337 #define __pte_to_swp_entry(pte) \
 338         ((swp_entry_t) { pte_val(pte_mkuptodate(pte)) })
 339 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 340
 341 #define kern_addr_valid(addr) (1)
 342
 343 #include <asm-generic/pgtable.h>
 344
 345 #endif