include/asm-mips64/pgtable.h

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 - 2001 by Ralf Baechle at alii
   7  * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
   8  */
   9 #ifndef _ASM_PGTABLE_H
  10 #define _ASM_PGTABLE_H
  11
  12 #include <linux/config.h>
  13 #include <asm/addrspace.h>
  14 #include <asm/page.h>
  15
  16 #ifndef __ASSEMBLY__
  17
  18 #include <linux/linkage.h>
  19 #include <linux/mmzone.h>
  20 #include <asm/cachectl.h>
  21
  22 /*
  23  * This flag is used to indicate that the page pointed to by a pte
  24  * is dirty and requires cleaning before returning it to the user.
  25  */
  26 #define PG_dcache_dirty                 PG_arch_1
  27
  28 #define Page_dcache_dirty(page)         \
  29         test_bit(PG_dcache_dirty, &(page)->flags)
  30 #define SetPageDcacheDirty(page)        \
  31         set_bit(PG_dcache_dirty, &(page)->flags)
  32 #define ClearPageDcacheDirty(page)      \
  33         clear_bit(PG_dcache_dirty, &(page)->flags)
  34
  35
  36 /*
  37  * Each address space has 2 4K pages as its page directory, giving 1024
  38  * (== PTRS_PER_PGD) 8 byte pointers to pmd tables. Each pmd table is a
  39  * pair of 4K pages, giving 1024 (== PTRS_PER_PMD) 8 byte pointers to
  40  * page tables. Each page table is a single 4K page, giving 512 (==
  41  * PTRS_PER_PTE) 8 byte ptes. Each pgde is initialized to point to
  42  * invalid_pmd_table, each pmde is initialized to point to
  43  * invalid_pte_table, each pte is initialized to 0. When memory is low,
  44  * and a pmd table or a page table allocation fails, empty_bad_pmd_table
  45  * and empty_bad_page_table is returned back to higher layer code, so
  46  * that the failure is recognized later on. Linux does not seem to
  47  * handle these failures very well though. The empty_bad_page_table has
  48  * invalid pte entries in it, to force page faults.
  49  * Vmalloc handling: vmalloc uses swapper_pg_dir[0] (returned by
  50  * pgd_offset_k), which is initalized to point to kpmdtbl. kpmdtbl is
  51  * the only single page pmd in the system. kpmdtbl entries point into
  52  * kptbl[] array. We reserve 1 << PGD_ORDER pages to hold the
  53  * vmalloc range translations, which the fault handler looks at.
  54  */
  55
  56 #endif /* !__ASSEMBLY__ */
  57
  58 /* PMD_SHIFT determines the size of the area a second-level page table can map */
  59 #define PMD_SHIFT       (PAGE_SHIFT + (PAGE_SHIFT - 3))
  60 #define PMD_SIZE        (1UL << PMD_SHIFT)
  61 #define PMD_MASK        (~(PMD_SIZE-1))
  62
  63 /* PGDIR_SHIFT determines what a third-level page table entry can map */
  64 #define PGDIR_SHIFT     (PMD_SHIFT + (PAGE_SHIFT + 1 - 3))
  65 #define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
  66 #define PGDIR_MASK      (~(PGDIR_SIZE-1))
  67
  68 /* Entries per page directory level: we use two-level, so we don't really
  69    have any PMD directory physically.  */
  70 #define PTRS_PER_PGD            1024
  71 #define PTRS_PER_PMD            1024
  72 #define PTRS_PER_PTE            512
  73 #define PGD_ORDER               1
  74 #define PMD_ORDER               1
  75 #define PTE_ORDER               0
  76
  77 #define USER_PTRS_PER_PGD       (TASK_SIZE / PGDIR_SIZE)
  78 #define FIRST_USER_PGD_NR       0
  79
  80 #define VMALLOC_START           XKSEG
  81 #define VMALLOC_VMADDR(x)       ((unsigned long)(x))
  82 #define VMALLOC_END     \
  83         (VMALLOC_START + ((1 << PGD_ORDER) * PTRS_PER_PTE * PAGE_SIZE))
  84
  85 #include <asm/pgtable-bits.h>
  86
  87 #define PAGE_NONE       __pgprot(_PAGE_PRESENT | _CACHE_CACHABLE_NONCOHERENT)
  88 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
  89                         PAGE_CACHABLE_DEFAULT)
  90 #define PAGE_COPY       __pgprot(_PAGE_PRESENT | _PAGE_READ | \
  91                         PAGE_CACHABLE_DEFAULT)
  92 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_READ | \
  93                         PAGE_CACHABLE_DEFAULT)
  94 #define PAGE_KERNEL     __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
  95                         _PAGE_GLOBAL | PAGE_CACHABLE_DEFAULT)
  96 #define PAGE_USERIO     __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
  97                         PAGE_CACHABLE_DEFAULT)
  98 #define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
  99                         __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
 100
 101 /*
 102  * MIPS can't do page protection for execute, and considers that the same like
 103  * read. Also, write permissions imply read permissions. This is the closest
 104  * we can get by reasonable means..
 105  */
 106 #define __P000  PAGE_NONE
 107 #define __P001  PAGE_READONLY
 108 #define __P010  PAGE_COPY
 109 #define __P011  PAGE_COPY
 110 #define __P100  PAGE_READONLY
 111 #define __P101  PAGE_READONLY
 112 #define __P110  PAGE_COPY
 113 #define __P111  PAGE_COPY
 114
 115 #define __S000  PAGE_NONE
 116 #define __S001  PAGE_READONLY
 117 #define __S010  PAGE_SHARED
 118 #define __S011  PAGE_SHARED
 119 #define __S100  PAGE_READONLY
 120 #define __S101  PAGE_READONLY
 121 #define __S110  PAGE_SHARED
 122 #define __S111  PAGE_SHARED
 123
 124 #ifndef __ASSEMBLY__
 125
 126 #define pte_ERROR(e) \
 127         printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
 128 #define pmd_ERROR(e) \
 129         printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
 130 #define pgd_ERROR(e) \
 131         printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
 132
 133 /*
 134  * ZERO_PAGE is a global shared page that is always zero; used
 135  * for zero-mapped memory areas etc..
 136  */
 137
 138 extern unsigned long empty_zero_page;
 139 extern unsigned long zero_page_mask;
 140
 141 #define ZERO_PAGE(vaddr) \
 142         (virt_to_page(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask)))
 143
 144 extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
 145 extern pte_t empty_bad_page_table[PAGE_SIZE/sizeof(pte_t)];
 146 extern pmd_t invalid_pmd_table[2*PAGE_SIZE/sizeof(pmd_t)];
 147 extern pmd_t empty_bad_pmd_table[2*PAGE_SIZE/sizeof(pmd_t)];
 148
 149 /*
 150  * Conversion functions: convert a page and protection to a page entry,
 151  * and a page entry and page directory to the page they refer to.
 152  */
 153 #define page_pte(page)          page_pte_prot(page, __pgprot(0))
 154 #define pmd_phys(pmd)           (pmd_val(pmd) - PAGE_OFFSET)
 155 #define pmd_page(pmd)           (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
 156 #define pmd_page_kernel(pmd)    pmd_val(pmd)
 157
 158 static inline unsigned long pgd_page(pgd_t pgd)
 159 {
 160         return pgd_val(pgd);
 161 }
 162
 163 static inline int pte_none(pte_t pte)
 164 {
 165         return !(pte_val(pte) & ~_PAGE_GLOBAL);
 166 }
 167
 168 static inline int pte_present(pte_t pte)
 169 {
 170         return pte_val(pte) & _PAGE_PRESENT;
 171 }
 172
 173 /*
 174  * Certain architectures need to do special things when pte's
 175  * within a page table are directly modified.  Thus, the following
 176  * hook is made available.
 177  */
 178 static inline void set_pte(pte_t *ptep, pte_t pteval)
 179 {
 180         *ptep = pteval;
 181 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
 182         if (pte_val(pteval) & _PAGE_GLOBAL) {
 183                 pte_t *buddy = ptep_buddy(ptep);
 184                 /*
 185                  * Make sure the buddy is global too (if it's !none,
 186                  * it better already be global)
 187                  */
 188                 if (pte_none(*buddy))
 189                         pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
 190         }
 191 #endif
 192 }
 193
 194 static inline void pte_clear(pte_t *ptep)
 195 {
 196 #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
 197         /* Preserve global status for the pair */
 198         if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
 199                 set_pte(ptep, __pte(_PAGE_GLOBAL));
 200         else
 201 #endif
 202                 set_pte(ptep, __pte(0));
 203 }
 204
 205 /*
 206  * (pmds are folded into pgds so this doesn't get actually called,
 207  * but the define is needed for a generic inline function.)
 208  */
 209 #define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)
 210 #define set_pgd(pgdptr, pgdval) do { *(pgdptr) = (pgdval); } while(0)
 211
 212 /*
 213  * Empty pmd entries point to the invalid_pte_table.
 214  */
 215 static inline int pmd_none(pmd_t pmd)
 216 {
 217         return pmd_val(pmd) == (unsigned long) invalid_pte_table;
 218 }
 219
 220 #define pmd_bad(pmd)            (pmd_val(pmd) &~ PAGE_MASK)
 221
 222 static inline int pmd_present(pmd_t pmd)
 223 {
 224         return pmd_val(pmd) != (unsigned long) invalid_pte_table;
 225 }
 226
 227 static inline void pmd_clear(pmd_t *pmdp)
 228 {
 229         pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
 230 }
 231
 232 /*
 233  * Empty pgd entries point to the invalid_pmd_table.
 234  */
 235 static inline int pgd_none(pgd_t pgd)
 236 {
 237         return pgd_val(pgd) == (unsigned long) invalid_pmd_table;
 238 }
 239
 240 #define pgd_bad(pgd)            (pgd_val(pgd) &~ PAGE_MASK)
 241
 242 static inline int pgd_present(pgd_t pgd)
 243 {
 244         return pgd_val(pgd) != (unsigned long) invalid_pmd_table;
 245 }
 246
 247 static inline void pgd_clear(pgd_t *pgdp)
 248 {
 249         pgd_val(*pgdp) = ((unsigned long) invalid_pmd_table);
 250 }
 251
 252 #ifdef CONFIG_DISCONTIGMEM
 253
 254 #define pte_page(x) (NODE_MEM_MAP(PHYSADDR_TO_NID(pte_val(x))) +        \
 255         PLAT_NODE_DATA_LOCALNR(pte_val(x), PHYSADDR_TO_NID(pte_val(x))))
 256
 257 #else
 258 #define pte_page(x)             (mem_map+(unsigned long)((pte_val(x) >> PAGE_SHIFT)))
 259 #define pte_pfn(x)              ((unsigned long)((x).pte >> PAGE_SHIFT))
 260 #define pfn_pte(pfn, prot)      __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 261 #endif
 262
 263 #define PTE_FILE_MAX_BITS       27
 264
 265 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
 266
 267 /*
 268  * Bits 0, 1, 2, 9 and 10 are taken, split up the 27 bits of offset
 269  * into this range:
 270  */
 271
 272 #define pte_to_pgoff(_pte) \
 273         ((((_pte).pte >> 3) & 0x3f ) + (((_pte).pte >> 11) << 8 ))
 274
 275 #define pgoff_to_pte(off) \
 276         ((pte_t) { (((off) & 0x3f) << 3) + (((off) >> 8) << 11) + _PAGE_FILE })
 277
 278 #else
 279
 280 /*
 281  * Bits 0, 1, 2, 7 and 8 are taken, split up the 27 bits of offset
 282  * into this range:
 283  */
 284 #define pte_to_pgoff(_pte) \
 285         ((((_pte).pte >> 3) & 0x1f ) + (((_pte).pte >> 9) << 6 ))
 286
 287 #define pgoff_to_pte(off) \
 288         ((pte_t) { (((off) & 0x1f) << 3) + (((off) >> 6) << 9) + _PAGE_FILE })
 289
 290 #endif
 291
 292 /*
 293  * The following only work if pte_present() is true.
 294  * Undefined behaviour if not..
 295  */
 296 static inline int pte_user(pte_t pte)   { BUG(); return 0; }
 297 static inline int pte_read(pte_t pte)   { return pte_val(pte) & _PAGE_READ; }
 298 static inline int pte_write(pte_t pte)  { return pte_val(pte) & _PAGE_WRITE; }
 299 static inline int pte_dirty(pte_t pte)  { return pte_val(pte) & _PAGE_MODIFIED; }
 300 static inline int pte_young(pte_t pte)  { return pte_val(pte) & _PAGE_ACCESSED; }
 301 static inline int pte_file(pte_t pte)   { return pte_val(pte) & _PAGE_FILE; }
 302
 303 static inline pte_t pte_wrprotect(pte_t pte)
 304 {
 305         pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
 306         return pte;
 307 }
 308
 309 static inline pte_t pte_rdprotect(pte_t pte)
 310 {
 311         pte_val(pte) &= ~(_PAGE_READ | _PAGE_SILENT_READ);
 312         return pte;
 313 }
 314
 315 static inline pte_t pte_mkclean(pte_t pte)
 316 {
 317         pte_val(pte) &= ~(_PAGE_MODIFIED|_PAGE_SILENT_WRITE);
 318         return pte;
 319 }
 320
 321 static inline pte_t pte_mkold(pte_t pte)
 322 {
 323         pte_val(pte) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
 324         return pte;
 325 }
 326
 327 static inline pte_t pte_mkwrite(pte_t pte)
 328 {
 329         pte_val(pte) |= _PAGE_WRITE;
 330         if (pte_val(pte) & _PAGE_MODIFIED)
 331                 pte_val(pte) |= _PAGE_SILENT_WRITE;
 332         return pte;
 333 }
 334
 335 static inline pte_t pte_mkread(pte_t pte)
 336 {
 337         pte_val(pte) |= _PAGE_READ;
 338         if (pte_val(pte) & _PAGE_ACCESSED)
 339                 pte_val(pte) |= _PAGE_SILENT_READ;
 340         return pte;
 341 }
 342
 343 static inline pte_t pte_mkdirty(pte_t pte)
 344 {
 345         pte_val(pte) |= _PAGE_MODIFIED;
 346         if (pte_val(pte) & _PAGE_WRITE)
 347                 pte_val(pte) |= _PAGE_SILENT_WRITE;
 348         return pte;
 349 }
 350
 351 static inline pte_t pte_mkyoung(pte_t pte)
 352 {
 353         pte_val(pte) |= _PAGE_ACCESSED;
 354         if (pte_val(pte) & _PAGE_READ)
 355                 pte_val(pte) |= _PAGE_SILENT_READ;
 356         return pte;
 357 }
 358
 359 /*
 360  * Macro to make mark a page protection value as "uncacheable".  Note
 361  * that "protection" is really a misnomer here as the protection value
 362  * contains the memory attribute bits, dirty bits, and various other
 363  * bits as well.
 364  */
 365 #define pgprot_noncached pgprot_noncached
 366
 367 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
 368 {
 369         unsigned long prot = pgprot_val(_prot);
 370
 371         prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
 372
 373         return __pgprot(prot);
 374 }
 375
 376 /*
 377  * Conversion functions: convert a page and protection to a page entry,
 378  * and a page entry and page directory to the page they refer to.
 379  */
 380 #define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 381
 382 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 383 {
 384         return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
 385 }
 386
 387 #define __pgd_offset(address)   pgd_index(address)
 388 #define page_pte(page) page_pte_prot(page, __pgprot(0))
 389
 390 /* to find an entry in a kernel page-table-directory */
 391 #define pgd_offset_k(address) pgd_offset(&init_mm, 0)
 392
 393 #define pgd_index(address)              ((address) >> PGDIR_SHIFT)
 394
 395 /* to find an entry in a page-table-directory */
 396 #define pgd_offset(mm,addr)     ((mm)->pgd + pgd_index(addr))
 397
 398 /* Find an entry in the second-level page table.. */
 399 static inline pmd_t *pmd_offset(pgd_t * dir, unsigned long address)
 400 {
 401         return (pmd_t *) pgd_page(*dir) +
 402                ((address >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
 403 }
 404
 405 /* Find an entry in the third-level page table.. */
 406 #define __pte_offset(address)                                           \
 407         (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
 408 #define pte_offset(dir, address)                                        \
 409         ((pte_t *) (pmd_page_kernel(*dir)) + __pte_offset(address))
 410 #define pte_offset_kernel(dir, address)                                 \
 411         ((pte_t *) pmd_page_kernel(*(dir)) +  __pte_offset(address))
 412 #define pte_offset_map(dir, address)                                    \
 413         ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
 414 #define pte_offset_map_nested(dir, address)                             \
 415         ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
 416 #define pte_unmap(pte) ((void)(pte))
 417 #define pte_unmap_nested(pte) ((void)(pte))
 418
 419 /*
 420  * Initialize a new pgd / pmd table with invalid pointers.
 421  */
 422 extern void pgd_init(unsigned long page);
 423 extern void pmd_init(unsigned long page, unsigned long pagetable);
 424
 425 extern pgd_t swapper_pg_dir[1024];
 426 extern void paging_init(void);
 427
 428 extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
 429         pte_t pte);
 430 extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
 431         pte_t pte);
 432
 433 static inline void update_mmu_cache(struct vm_area_struct *vma,
 434         unsigned long address, pte_t pte)
 435 {
 436         __update_tlb(vma, address, pte);
 437         __update_cache(vma, address, pte);
 438 }
 439
 440 /*
 441  * Non-present pages:  high 24 bits are offset, next 8 bits type,
 442  * low 32 bits zero.
 443  */
 444 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
 445 { pte_t pte; pte_val(pte) = (type << 32) | (offset << 40); return pte; }
 446
 447 #define __swp_type(x)           (((x).val >> 32) & 0xff)
 448 #define __swp_offset(x)         ((x).val >> 40)
 449 #define __swp_entry(type,offset) ((swp_entry_t) { pte_val(mk_swap_pte((type),(offset))) })
 450 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
 451 #define __swp_entry_to_pte(x)   ((pte_t) { (x).val })
 452
 453 #ifndef CONFIG_DISCONTIGMEM
 454 #define kern_addr_valid(addr)   (1)
 455 #endif
 456
 457 /*
 458  * No page table caches to initialise
 459  */
 460 #define pgtable_cache_init()    do { } while (0)
 461
 462 #include <asm-generic/pgtable.h>
 463
 464 typedef pte_t *pte_addr_t;
 465
 466 /*
 467  * We provide our own get_unmapped area to cope with the virtual aliasing
 468  * constraints placed on us by the cache architecture.
 469  */
 470 #define HAVE_ARCH_UNMAPPED_AREA
 471
 472 #define io_remap_page_range remap_page_range
 473
 474 #endif /* !__ASSEMBLY__ */
 475
 476 #endif /* _ASM_PGTABLE_H */