include/asm-x86/pgtable.h

   1 #ifndef _ASM_X86_PGTABLE_H
   2 #define _ASM_X86_PGTABLE_H
   3
   4 #define FIRST_USER_ADDRESS      0
   5
   6 #define _PAGE_BIT_PRESENT       0       /* is present */
   7 #define _PAGE_BIT_RW            1       /* writeable */
   8 #define _PAGE_BIT_USER          2       /* userspace addressable */
   9 #define _PAGE_BIT_PWT           3       /* page write through */
  10 #define _PAGE_BIT_PCD           4       /* page cache disabled */
  11 #define _PAGE_BIT_ACCESSED      5       /* was accessed (raised by CPU) */
  12 #define _PAGE_BIT_DIRTY         6       /* was written to (raised by CPU) */
  13 #define _PAGE_BIT_FILE          6
  14 #define _PAGE_BIT_PSE           7       /* 4 MB (or 2MB) page */
  15 #define _PAGE_BIT_PAT           7       /* on 4KB pages */
  16 #define _PAGE_BIT_GLOBAL        8       /* Global TLB entry PPro+ */
  17 #define _PAGE_BIT_UNUSED1       9       /* available for programmer */
  18 #define _PAGE_BIT_UNUSED2       10
  19 #define _PAGE_BIT_UNUSED3       11
  20 #define _PAGE_BIT_PAT_LARGE     12      /* On 2MB or 1GB pages */
  21 #define _PAGE_BIT_NX           63       /* No execute: only valid after cpuid check */
  22
  23 /*
  24  * Note: we use _AC(1, L) instead of _AC(1, UL) so that we get a
  25  * sign-extended value on 32-bit with all 1's in the upper word,
  26  * which preserves the upper pte values on 64-bit ptes:
  27  */
  28 #define _PAGE_PRESENT   (_AC(1, L)<<_PAGE_BIT_PRESENT)
  29 #define _PAGE_RW        (_AC(1, L)<<_PAGE_BIT_RW)
  30 #define _PAGE_USER      (_AC(1, L)<<_PAGE_BIT_USER)
  31 #define _PAGE_PWT       (_AC(1, L)<<_PAGE_BIT_PWT)
  32 #define _PAGE_PCD       (_AC(1, L)<<_PAGE_BIT_PCD)
  33 #define _PAGE_ACCESSED  (_AC(1, L)<<_PAGE_BIT_ACCESSED)
  34 #define _PAGE_DIRTY     (_AC(1, L)<<_PAGE_BIT_DIRTY)
  35 #define _PAGE_PSE       (_AC(1, L)<<_PAGE_BIT_PSE)      /* 2MB page */
  36 #define _PAGE_GLOBAL    (_AC(1, L)<<_PAGE_BIT_GLOBAL)   /* Global TLB entry */
  37 #define _PAGE_UNUSED1   (_AC(1, L)<<_PAGE_BIT_UNUSED1)
  38 #define _PAGE_UNUSED2   (_AC(1, L)<<_PAGE_BIT_UNUSED2)
  39 #define _PAGE_UNUSED3   (_AC(1, L)<<_PAGE_BIT_UNUSED3)
  40 #define _PAGE_PAT       (_AC(1, L)<<_PAGE_BIT_PAT)
  41 #define _PAGE_PAT_LARGE (_AC(1, L)<<_PAGE_BIT_PAT_LARGE)
  42
  43 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
  44 #define _PAGE_NX        (_AC(1, ULL) << _PAGE_BIT_NX)
  45 #else
  46 #define _PAGE_NX        0
  47 #endif
  48
  49 /* If _PAGE_PRESENT is clear, we use these: */
  50 #define _PAGE_FILE      _PAGE_DIRTY     /* nonlinear file mapping,
  51                                          * saved PTE; unset:swap */
  52 #define _PAGE_PROTNONE  _PAGE_PSE       /* if the user mapped it with PROT_NONE;
  53                                            pte_present gives true */
  54
  55 #define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |        \
  56                          _PAGE_ACCESSED | _PAGE_DIRTY)
  57 #define _KERNPG_TABLE   (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED |    \
  58                          _PAGE_DIRTY)
  59
  60 /* Set of bits not changed in pte_modify */
  61 #define _PAGE_CHG_MASK  (PTE_MASK | _PAGE_PCD | _PAGE_PWT |             \
  62                          _PAGE_ACCESSED | _PAGE_DIRTY)
  63
  64 #define _PAGE_CACHE_MASK        (_PAGE_PCD | _PAGE_PWT)
  65 #define _PAGE_CACHE_WB          (0)
  66 #define _PAGE_CACHE_WC          (_PAGE_PWT)
  67 #define _PAGE_CACHE_UC_MINUS    (_PAGE_PCD)
  68 #define _PAGE_CACHE_UC          (_PAGE_PCD | _PAGE_PWT)
  69
  70 #define PAGE_NONE       __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
  71 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
  72                                  _PAGE_ACCESSED | _PAGE_NX)
  73
  74 #define PAGE_SHARED_EXEC        __pgprot(_PAGE_PRESENT | _PAGE_RW |     \
  75                                          _PAGE_USER | _PAGE_ACCESSED)
  76 #define PAGE_COPY_NOEXEC        __pgprot(_PAGE_PRESENT | _PAGE_USER |   \
  77                                          _PAGE_ACCESSED | _PAGE_NX)
  78 #define PAGE_COPY_EXEC          __pgprot(_PAGE_PRESENT | _PAGE_USER |   \
  79                                          _PAGE_ACCESSED)
  80 #define PAGE_COPY               PAGE_COPY_NOEXEC
  81 #define PAGE_READONLY           __pgprot(_PAGE_PRESENT | _PAGE_USER |   \
  82                                          _PAGE_ACCESSED | _PAGE_NX)
  83 #define PAGE_READONLY_EXEC      __pgprot(_PAGE_PRESENT | _PAGE_USER |   \
  84                                          _PAGE_ACCESSED)
  85
  86 #ifdef CONFIG_X86_32
  87 #define _PAGE_KERNEL_EXEC \
  88         (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  89 #define _PAGE_KERNEL (_PAGE_KERNEL_EXEC | _PAGE_NX)
  90
  91 #ifndef __ASSEMBLY__
  92 extern pteval_t __PAGE_KERNEL, __PAGE_KERNEL_EXEC;
  93 #endif  /* __ASSEMBLY__ */
  94 #else
  95 #define __PAGE_KERNEL_EXEC                                              \
  96         (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
  97 #define __PAGE_KERNEL           (__PAGE_KERNEL_EXEC | _PAGE_NX)
  98 #endif
  99
 100 #define __PAGE_KERNEL_RO                (__PAGE_KERNEL & ~_PAGE_RW)
 101 #define __PAGE_KERNEL_RX                (__PAGE_KERNEL_EXEC & ~_PAGE_RW)
 102 #define __PAGE_KERNEL_EXEC_NOCACHE      (__PAGE_KERNEL_EXEC | _PAGE_PCD | _PAGE_PWT)
 103 #define __PAGE_KERNEL_WC                (__PAGE_KERNEL | _PAGE_CACHE_WC)
 104 #define __PAGE_KERNEL_NOCACHE           (__PAGE_KERNEL | _PAGE_PCD | _PAGE_PWT)
 105 #define __PAGE_KERNEL_UC_MINUS          (__PAGE_KERNEL | _PAGE_PCD)
 106 #define __PAGE_KERNEL_VSYSCALL          (__PAGE_KERNEL_RX | _PAGE_USER)
 107 #define __PAGE_KERNEL_VSYSCALL_NOCACHE  (__PAGE_KERNEL_VSYSCALL | _PAGE_PCD | _PAGE_PWT)
 108 #define __PAGE_KERNEL_LARGE             (__PAGE_KERNEL | _PAGE_PSE)
 109 #define __PAGE_KERNEL_LARGE_EXEC        (__PAGE_KERNEL_EXEC | _PAGE_PSE)
 110
 111 #ifdef CONFIG_X86_32
 112 # define MAKE_GLOBAL(x)                 __pgprot((x))
 113 #else
 114 # define MAKE_GLOBAL(x)                 __pgprot((x) | _PAGE_GLOBAL)
 115 #endif
 116
 117 #define PAGE_KERNEL                     MAKE_GLOBAL(__PAGE_KERNEL)
 118 #define PAGE_KERNEL_RO                  MAKE_GLOBAL(__PAGE_KERNEL_RO)
 119 #define PAGE_KERNEL_EXEC                MAKE_GLOBAL(__PAGE_KERNEL_EXEC)
 120 #define PAGE_KERNEL_RX                  MAKE_GLOBAL(__PAGE_KERNEL_RX)
 121 #define PAGE_KERNEL_WC                  MAKE_GLOBAL(__PAGE_KERNEL_WC)
 122 #define PAGE_KERNEL_NOCACHE             MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
 123 #define PAGE_KERNEL_UC_MINUS            MAKE_GLOBAL(__PAGE_KERNEL_UC_MINUS)
 124 #define PAGE_KERNEL_EXEC_NOCACHE        MAKE_GLOBAL(__PAGE_KERNEL_EXEC_NOCACHE)
 125 #define PAGE_KERNEL_LARGE               MAKE_GLOBAL(__PAGE_KERNEL_LARGE)
 126 #define PAGE_KERNEL_LARGE_EXEC          MAKE_GLOBAL(__PAGE_KERNEL_LARGE_EXEC)
 127 #define PAGE_KERNEL_VSYSCALL            MAKE_GLOBAL(__PAGE_KERNEL_VSYSCALL)
 128 #define PAGE_KERNEL_VSYSCALL_NOCACHE    MAKE_GLOBAL(__PAGE_KERNEL_VSYSCALL_NOCACHE)
 129
 130 /*         xwr */
 131 #define __P000  PAGE_NONE
 132 #define __P001  PAGE_READONLY
 133 #define __P010  PAGE_COPY
 134 #define __P011  PAGE_COPY
 135 #define __P100  PAGE_READONLY_EXEC
 136 #define __P101  PAGE_READONLY_EXEC
 137 #define __P110  PAGE_COPY_EXEC
 138 #define __P111  PAGE_COPY_EXEC
 139
 140 #define __S000  PAGE_NONE
 141 #define __S001  PAGE_READONLY
 142 #define __S010  PAGE_SHARED
 143 #define __S011  PAGE_SHARED
 144 #define __S100  PAGE_READONLY_EXEC
 145 #define __S101  PAGE_READONLY_EXEC
 146 #define __S110  PAGE_SHARED_EXEC
 147 #define __S111  PAGE_SHARED_EXEC
 148
 149 #ifndef __ASSEMBLY__
 150
 151 /*
 152  * ZERO_PAGE is a global shared page that is always zero: used
 153  * for zero-mapped memory areas etc..
 154  */
 155 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
 156 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
 157
 158 extern spinlock_t pgd_lock;
 159 extern struct list_head pgd_list;
 160
 161 /*
 162  * The following only work if pte_present() is true.
 163  * Undefined behaviour if not..
 164  */
 165 static inline int pte_dirty(pte_t pte)
 166 {
 167         return pte_val(pte) & _PAGE_DIRTY;
 168 }
 169
 170 static inline int pte_young(pte_t pte)
 171 {
 172         return pte_val(pte) & _PAGE_ACCESSED;
 173 }
 174
 175 static inline int pte_write(pte_t pte)
 176 {
 177         return pte_val(pte) & _PAGE_RW;
 178 }
 179
 180 static inline int pte_file(pte_t pte)
 181 {
 182         return pte_val(pte) & _PAGE_FILE;
 183 }
 184
 185 static inline int pte_huge(pte_t pte)
 186 {
 187         return pte_val(pte) & _PAGE_PSE;
 188 }
 189
 190 static inline int pte_global(pte_t pte)
 191 {
 192         return pte_val(pte) & _PAGE_GLOBAL;
 193 }
 194
 195 static inline int pte_exec(pte_t pte)
 196 {
 197         return !(pte_val(pte) & _PAGE_NX);
 198 }
 199
 200 static inline int pte_special(pte_t pte)
 201 {
 202         return 0;
 203 }
 204
 205 static inline int pmd_large(pmd_t pte)
 206 {
 207         return (pmd_val(pte) & (_PAGE_PSE | _PAGE_PRESENT)) ==
 208                 (_PAGE_PSE | _PAGE_PRESENT);
 209 }
 210
 211 static inline pte_t pte_mkclean(pte_t pte)
 212 {
 213         return __pte(pte_val(pte) & ~(pteval_t)_PAGE_DIRTY);
 214 }
 215
 216 static inline pte_t pte_mkold(pte_t pte)
 217 {
 218         return __pte(pte_val(pte) & ~(pteval_t)_PAGE_ACCESSED);
 219 }
 220
 221 static inline pte_t pte_wrprotect(pte_t pte)
 222 {
 223         return __pte(pte_val(pte) & ~(pteval_t)_PAGE_RW);
 224 }
 225
 226 static inline pte_t pte_mkexec(pte_t pte)
 227 {
 228         return __pte(pte_val(pte) & ~(pteval_t)_PAGE_NX);
 229 }
 230
 231 static inline pte_t pte_mkdirty(pte_t pte)
 232 {
 233         return __pte(pte_val(pte) | _PAGE_DIRTY);
 234 }
 235
 236 static inline pte_t pte_mkyoung(pte_t pte)
 237 {
 238         return __pte(pte_val(pte) | _PAGE_ACCESSED);
 239 }
 240
 241 static inline pte_t pte_mkwrite(pte_t pte)
 242 {
 243         return __pte(pte_val(pte) | _PAGE_RW);
 244 }
 245
 246 static inline pte_t pte_mkhuge(pte_t pte)
 247 {
 248         return __pte(pte_val(pte) | _PAGE_PSE);
 249 }
 250
 251 static inline pte_t pte_clrhuge(pte_t pte)
 252 {
 253         return __pte(pte_val(pte) & ~(pteval_t)_PAGE_PSE);
 254 }
 255
 256 static inline pte_t pte_mkglobal(pte_t pte)
 257 {
 258         return __pte(pte_val(pte) | _PAGE_GLOBAL);
 259 }
 260
 261 static inline pte_t pte_clrglobal(pte_t pte)
 262 {
 263         return __pte(pte_val(pte) & ~(pteval_t)_PAGE_GLOBAL);
 264 }
 265
 266 static inline pte_t pte_mkspecial(pte_t pte)
 267 {
 268         return pte;
 269 }
 270
 271 extern pteval_t __supported_pte_mask;
 272
 273 static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
 274 {
 275         return __pte((((phys_addr_t)page_nr << PAGE_SHIFT) |
 276                       pgprot_val(pgprot)) & __supported_pte_mask);
 277 }
 278
 279 static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
 280 {
 281         return __pmd((((phys_addr_t)page_nr << PAGE_SHIFT) |
 282                       pgprot_val(pgprot)) & __supported_pte_mask);
 283 }
 284
 285 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 286 {
 287         pteval_t val = pte_val(pte);
 288
 289         /*
 290          * Chop off the NX bit (if present), and add the NX portion of
 291          * the newprot (if present):
 292          */
 293         val &= _PAGE_CHG_MASK;
 294         val |= pgprot_val(newprot) & (~_PAGE_CHG_MASK) & __supported_pte_mask;
 295
 296         return __pte(val);
 297 }
 298
 299 /* mprotect needs to preserve PAT bits when updating vm_page_prot */
 300 #define pgprot_modify pgprot_modify
 301 static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
 302 {
 303         pgprotval_t preservebits = pgprot_val(oldprot) & _PAGE_CHG_MASK;
 304         pgprotval_t addbits = pgprot_val(newprot);
 305         return __pgprot(preservebits | addbits);
 306 }
 307
 308 #define pte_pgprot(x) __pgprot(pte_val(x) & ~PTE_MASK)
 309
 310 #define canon_pgprot(p) __pgprot(pgprot_val(p) & __supported_pte_mask)
 311
 312 #ifndef __ASSEMBLY__
 313 #define __HAVE_PHYS_MEM_ACCESS_PROT
 314 struct file;
 315 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 316                               unsigned long size, pgprot_t vma_prot);
 317 int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
 318                               unsigned long size, pgprot_t *vma_prot);
 319 #endif
 320
 321 #ifdef CONFIG_PARAVIRT
 322 #include <asm/paravirt.h>
 323 #else  /* !CONFIG_PARAVIRT */
 324 #define set_pte(ptep, pte)              native_set_pte(ptep, pte)
 325 #define set_pte_at(mm, addr, ptep, pte) native_set_pte_at(mm, addr, ptep, pte)
 326
 327 #define set_pte_present(mm, addr, ptep, pte)                            \
 328         native_set_pte_present(mm, addr, ptep, pte)
 329 #define set_pte_atomic(ptep, pte)                                       \
 330         native_set_pte_atomic(ptep, pte)
 331
 332 #define set_pmd(pmdp, pmd)              native_set_pmd(pmdp, pmd)
 333
 334 #ifndef __PAGETABLE_PUD_FOLDED
 335 #define set_pgd(pgdp, pgd)              native_set_pgd(pgdp, pgd)
 336 #define pgd_clear(pgd)                  native_pgd_clear(pgd)
 337 #endif
 338
 339 #ifndef set_pud
 340 # define set_pud(pudp, pud)             native_set_pud(pudp, pud)
 341 #endif
 342
 343 #ifndef __PAGETABLE_PMD_FOLDED
 344 #define pud_clear(pud)                  native_pud_clear(pud)
 345 #endif
 346
 347 #define pte_clear(mm, addr, ptep)       native_pte_clear(mm, addr, ptep)
 348 #define pmd_clear(pmd)                  native_pmd_clear(pmd)
 349
 350 #define pte_update(mm, addr, ptep)              do { } while (0)
 351 #define pte_update_defer(mm, addr, ptep)        do { } while (0)
 352 #endif  /* CONFIG_PARAVIRT */
 353
 354 #endif  /* __ASSEMBLY__ */
 355
 356 #ifdef CONFIG_X86_32
 357 # include "pgtable_32.h"
 358 #else
 359 # include "pgtable_64.h"
 360 #endif
 361
 362 #define KERNEL_PGD_BOUNDARY     pgd_index(PAGE_OFFSET)
 363 #define KERNEL_PGD_PTRS         (PTRS_PER_PGD - KERNEL_PGD_BOUNDARY)
 364
 365 #ifndef __ASSEMBLY__
 366
 367 enum {
 368         PG_LEVEL_NONE,
 369         PG_LEVEL_4K,
 370         PG_LEVEL_2M,
 371         PG_LEVEL_1G,
 372 };
 373
 374 /*
 375  * Helper function that returns the kernel pagetable entry controlling
 376  * the virtual address 'address'. NULL means no pagetable entry present.
 377  * NOTE: the return type is pte_t but if the pmd is PSE then we return it
 378  * as a pte too.
 379  */
 380 extern pte_t *lookup_address(unsigned long address, unsigned int *level);
 381
 382 /* local pte updates need not use xchg for locking */
 383 static inline pte_t native_local_ptep_get_and_clear(pte_t *ptep)
 384 {
 385         pte_t res = *ptep;
 386
 387         /* Pure native function needs no input for mm, addr */
 388         native_pte_clear(NULL, 0, ptep);
 389         return res;
 390 }
 391
 392 static inline void native_set_pte_at(struct mm_struct *mm, unsigned long addr,
 393                                      pte_t *ptep , pte_t pte)
 394 {
 395         native_set_pte(ptep, pte);
 396 }
 397
 398 #ifndef CONFIG_PARAVIRT
 399 /*
 400  * Rules for using pte_update - it must be called after any PTE update which
 401  * has not been done using the set_pte / clear_pte interfaces.  It is used by
 402  * shadow mode hypervisors to resynchronize the shadow page tables.  Kernel PTE
 403  * updates should either be sets, clears, or set_pte_atomic for P->P
 404  * transitions, which means this hook should only be called for user PTEs.
 405  * This hook implies a P->P protection or access change has taken place, which
 406  * requires a subsequent TLB flush.  The notification can optionally be delayed
 407  * until the TLB flush event by using the pte_update_defer form of the
 408  * interface, but care must be taken to assure that the flush happens while
 409  * still holding the same page table lock so that the shadow and primary pages
 410  * do not become out of sync on SMP.
 411  */
 412 #define pte_update(mm, addr, ptep)              do { } while (0)
 413 #define pte_update_defer(mm, addr, ptep)        do { } while (0)
 414 #endif
 415
 416 /*
 417  * We only update the dirty/accessed state if we set
 418  * the dirty bit by hand in the kernel, since the hardware
 419  * will do the accessed bit for us, and we don't want to
 420  * race with other CPU's that might be updating the dirty
 421  * bit at the same time.
 422  */
 423 #define  __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
 424 extern int ptep_set_access_flags(struct vm_area_struct *vma,
 425                                  unsigned long address, pte_t *ptep,
 426                                  pte_t entry, int dirty);
 427
 428 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 429 extern int ptep_test_and_clear_young(struct vm_area_struct *vma,
 430                                      unsigned long addr, pte_t *ptep);
 431
 432 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
 433 extern int ptep_clear_flush_young(struct vm_area_struct *vma,
 434                                   unsigned long address, pte_t *ptep);
 435
 436 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 437 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 438                                        pte_t *ptep)
 439 {
 440         pte_t pte = native_ptep_get_and_clear(ptep);
 441         pte_update(mm, addr, ptep);
 442         return pte;
 443 }
 444
 445 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
 446 static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
 447                                             unsigned long addr, pte_t *ptep,
 448                                             int full)
 449 {
 450         pte_t pte;
 451         if (full) {
 452                 /*
 453                  * Full address destruction in progress; paravirt does not
 454                  * care about updates and native needs no locking
 455                  */
 456                 pte = native_local_ptep_get_and_clear(ptep);
 457         } else {
 458                 pte = ptep_get_and_clear(mm, addr, ptep);
 459         }
 460         return pte;
 461 }
 462
 463 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 464 static inline void ptep_set_wrprotect(struct mm_struct *mm,
 465                                       unsigned long addr, pte_t *ptep)
 466 {
 467         clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte);
 468         pte_update(mm, addr, ptep);
 469 }
 470
 471 /*
 472  * clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
 473  *
 474  *  dst - pointer to pgd range anwhere on a pgd page
 475  *  src - ""
 476  *  count - the number of pgds to copy.
 477  *
 478  * dst and src can be on the same page, but the range must not overlap,
 479  * and must not cross a page boundary.
 480  */
 481 static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
 482 {
 483        memcpy(dst, src, count * sizeof(pgd_t));
 484 }
 485
 486
 487 #include <asm-generic/pgtable.h>
 488 #endif  /* __ASSEMBLY__ */
 489
 490 #endif  /* _ASM_X86_PGTABLE_H */