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