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
  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 #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
 130 static 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  */
 139 static 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
 145 static inline int pte_exec(pte_t pte){
 146         return((pte_get_bits(pte, _PAGE_USER)) &&
 147                !(pte_get_bits(pte, _PAGE_PROTNONE)));
 148 }
 149
 150 static 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  */
 159 static inline int pte_file(pte_t pte)
 160 {
 161         return pte_get_bits(pte, _PAGE_FILE);
 162 }
 163
 164 static inline int pte_dirty(pte_t pte)
 165 {
 166         return pte_get_bits(pte, _PAGE_DIRTY);
 167 }
 168
 169 static inline int pte_young(pte_t pte)
 170 {
 171         return pte_get_bits(pte, _PAGE_ACCESSED);
 172 }
 173
 174 static inline int pte_newpage(pte_t pte)
 175 {
 176         return pte_get_bits(pte, _PAGE_NEWPAGE);
 177 }
 178
 179 static inline int pte_newprot(pte_t pte)
 180 {
 181         return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
 182 }
 183
 184 static inline int pte_special(pte_t pte)
 185 {
 186         return 0;
 187 }
 188
 189 /*
 190  * =================================
 191  * Flags setting section.
 192  * =================================
 193  */
 194
 195 static inline pte_t pte_mknewprot(pte_t pte)
 196 {
 197         pte_set_bits(pte, _PAGE_NEWPROT);
 198         return(pte);
 199 }
 200
 201 static inline pte_t pte_mkclean(pte_t pte)
 202 {
 203         pte_clear_bits(pte, _PAGE_DIRTY);
 204         return(pte);
 205 }
 206
 207 static inline pte_t pte_mkold(pte_t pte)
 208 {
 209         pte_clear_bits(pte, _PAGE_ACCESSED);
 210         return(pte);
 211 }
 212
 213 static inline pte_t pte_wrprotect(pte_t pte)
 214 {
 215         pte_clear_bits(pte, _PAGE_RW);
 216         return(pte_mknewprot(pte));
 217 }
 218
 219 static inline pte_t pte_mkread(pte_t pte)
 220 {
 221         pte_set_bits(pte, _PAGE_USER);
 222         return(pte_mknewprot(pte));
 223 }
 224
 225 static inline pte_t pte_mkdirty(pte_t pte)
 226 {
 227         pte_set_bits(pte, _PAGE_DIRTY);
 228         return(pte);
 229 }
 230
 231 static inline pte_t pte_mkyoung(pte_t pte)
 232 {
 233         pte_set_bits(pte, _PAGE_ACCESSED);
 234         return(pte);
 235 }
 236
 237 static inline pte_t pte_mkwrite(pte_t pte)
 238 {
 239         pte_set_bits(pte, _PAGE_RW);
 240         return(pte_mknewprot(pte));
 241 }
 242
 243 static 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
 251 static inline pte_t pte_mknewpage(pte_t pte)
 252 {
 253         pte_set_bits(pte, _PAGE_NEWPAGE);
 254         return(pte);
 255 }
 256
 257 static inline pte_t pte_mkspecial(pte_t pte)
 258 {
 259         return(pte);
 260 }
 261
 262 static 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
 277 static 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
 300 static 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
 351 struct mm_struct;
 352 extern 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)           \
 372 do {                                            \
 373         pte_clear(&init_mm, (vaddr), (ptep));   \
 374         __flush_tlb_one((vaddr));               \
 375 } while (0)
 376
 377 #endif