pgtable.h 15 KB

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  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) 2003 Ralf Baechle
  7. */
  8. #ifndef _ASM_PGTABLE_H
  9. #define _ASM_PGTABLE_H
  10. #include <linux/mm_types.h>
  11. #include <linux/mmzone.h>
  12. #ifdef CONFIG_32BIT
  13. #include <asm/pgtable-32.h>
  14. #endif
  15. #ifdef CONFIG_64BIT
  16. #include <asm/pgtable-64.h>
  17. #endif
  18. #include <asm/io.h>
  19. #include <asm/pgtable-bits.h>
  20. struct mm_struct;
  21. struct vm_area_struct;
  22. #define PAGE_NONE __pgprot(_PAGE_PRESENT | _CACHE_CACHABLE_NONCOHERENT)
  23. #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_WRITE | (cpu_has_rixi ? 0 : _PAGE_READ) | \
  24. _page_cachable_default)
  25. #define PAGE_COPY __pgprot(_PAGE_PRESENT | (cpu_has_rixi ? 0 : _PAGE_READ) | \
  26. (cpu_has_rixi ? _PAGE_NO_EXEC : 0) | _page_cachable_default)
  27. #define PAGE_READONLY __pgprot(_PAGE_PRESENT | (cpu_has_rixi ? 0 : _PAGE_READ) | \
  28. _page_cachable_default)
  29. #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
  30. _PAGE_GLOBAL | _page_cachable_default)
  31. #define PAGE_USERIO __pgprot(_PAGE_PRESENT | (cpu_has_rixi ? 0 : _PAGE_READ) | _PAGE_WRITE | \
  32. _page_cachable_default)
  33. #define PAGE_KERNEL_UNCACHED __pgprot(_PAGE_PRESENT | __READABLE | \
  34. __WRITEABLE | _PAGE_GLOBAL | _CACHE_UNCACHED)
  35. /*
  36. * If _PAGE_NO_EXEC is not defined, we can't do page protection for
  37. * execute, and consider it to be the same as read. Also, write
  38. * permissions imply read permissions. This is the closest we can get
  39. * by reasonable means..
  40. */
  41. /*
  42. * Dummy values to fill the table in mmap.c
  43. * The real values will be generated at runtime
  44. */
  45. #define __P000 __pgprot(0)
  46. #define __P001 __pgprot(0)
  47. #define __P010 __pgprot(0)
  48. #define __P011 __pgprot(0)
  49. #define __P100 __pgprot(0)
  50. #define __P101 __pgprot(0)
  51. #define __P110 __pgprot(0)
  52. #define __P111 __pgprot(0)
  53. #define __S000 __pgprot(0)
  54. #define __S001 __pgprot(0)
  55. #define __S010 __pgprot(0)
  56. #define __S011 __pgprot(0)
  57. #define __S100 __pgprot(0)
  58. #define __S101 __pgprot(0)
  59. #define __S110 __pgprot(0)
  60. #define __S111 __pgprot(0)
  61. extern unsigned long _page_cachable_default;
  62. /*
  63. * ZERO_PAGE is a global shared page that is always zero; used
  64. * for zero-mapped memory areas etc..
  65. */
  66. extern unsigned long empty_zero_page;
  67. extern unsigned long zero_page_mask;
  68. #define ZERO_PAGE(vaddr) \
  69. (virt_to_page((void *)(empty_zero_page + (((unsigned long)(vaddr)) & zero_page_mask))))
  70. #define __HAVE_COLOR_ZERO_PAGE
  71. extern void paging_init(void);
  72. /*
  73. * Conversion functions: convert a page and protection to a page entry,
  74. * and a page entry and page directory to the page they refer to.
  75. */
  76. #define pmd_phys(pmd) virt_to_phys((void *)pmd_val(pmd))
  77. #define __pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
  78. #ifndef CONFIG_TRANSPARENT_HUGEPAGE
  79. #define pmd_page(pmd) __pmd_page(pmd)
  80. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  81. #define pmd_page_vaddr(pmd) pmd_val(pmd)
  82. #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
  83. #define pte_none(pte) (!(((pte).pte_low | (pte).pte_high) & ~_PAGE_GLOBAL))
  84. #define pte_present(pte) ((pte).pte_low & _PAGE_PRESENT)
  85. static inline void set_pte(pte_t *ptep, pte_t pte)
  86. {
  87. ptep->pte_high = pte.pte_high;
  88. smp_wmb();
  89. ptep->pte_low = pte.pte_low;
  90. if (pte.pte_low & _PAGE_GLOBAL) {
  91. pte_t *buddy = ptep_buddy(ptep);
  92. /*
  93. * Make sure the buddy is global too (if it's !none,
  94. * it better already be global)
  95. */
  96. if (pte_none(*buddy)) {
  97. buddy->pte_low |= _PAGE_GLOBAL;
  98. buddy->pte_high |= _PAGE_GLOBAL;
  99. }
  100. }
  101. }
  102. #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
  103. static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
  104. {
  105. pte_t null = __pte(0);
  106. /* Preserve global status for the pair */
  107. if (ptep_buddy(ptep)->pte_low & _PAGE_GLOBAL)
  108. null.pte_low = null.pte_high = _PAGE_GLOBAL;
  109. set_pte_at(mm, addr, ptep, null);
  110. }
  111. #else
  112. #define pte_none(pte) (!(pte_val(pte) & ~_PAGE_GLOBAL))
  113. #define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)
  114. /*
  115. * Certain architectures need to do special things when pte's
  116. * within a page table are directly modified. Thus, the following
  117. * hook is made available.
  118. */
  119. static inline void set_pte(pte_t *ptep, pte_t pteval)
  120. {
  121. *ptep = pteval;
  122. #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
  123. if (pte_val(pteval) & _PAGE_GLOBAL) {
  124. pte_t *buddy = ptep_buddy(ptep);
  125. /*
  126. * Make sure the buddy is global too (if it's !none,
  127. * it better already be global)
  128. */
  129. if (pte_none(*buddy))
  130. pte_val(*buddy) = pte_val(*buddy) | _PAGE_GLOBAL;
  131. }
  132. #endif
  133. }
  134. #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
  135. static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
  136. {
  137. #if !defined(CONFIG_CPU_R3000) && !defined(CONFIG_CPU_TX39XX)
  138. /* Preserve global status for the pair */
  139. if (pte_val(*ptep_buddy(ptep)) & _PAGE_GLOBAL)
  140. set_pte_at(mm, addr, ptep, __pte(_PAGE_GLOBAL));
  141. else
  142. #endif
  143. set_pte_at(mm, addr, ptep, __pte(0));
  144. }
  145. #endif
  146. /*
  147. * (pmds are folded into puds so this doesn't get actually called,
  148. * but the define is needed for a generic inline function.)
  149. */
  150. #define set_pmd(pmdptr, pmdval) do { *(pmdptr) = (pmdval); } while(0)
  151. #ifndef __PAGETABLE_PMD_FOLDED
  152. /*
  153. * (puds are folded into pgds so this doesn't get actually called,
  154. * but the define is needed for a generic inline function.)
  155. */
  156. #define set_pud(pudptr, pudval) do { *(pudptr) = (pudval); } while(0)
  157. #endif
  158. #define PGD_T_LOG2 (__builtin_ffs(sizeof(pgd_t)) - 1)
  159. #define PMD_T_LOG2 (__builtin_ffs(sizeof(pmd_t)) - 1)
  160. #define PTE_T_LOG2 (__builtin_ffs(sizeof(pte_t)) - 1)
  161. /*
  162. * We used to declare this array with size but gcc 3.3 and older are not able
  163. * to find that this expression is a constant, so the size is dropped.
  164. */
  165. extern pgd_t swapper_pg_dir[];
  166. /*
  167. * The following only work if pte_present() is true.
  168. * Undefined behaviour if not..
  169. */
  170. #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
  171. static inline int pte_write(pte_t pte) { return pte.pte_low & _PAGE_WRITE; }
  172. static inline int pte_dirty(pte_t pte) { return pte.pte_low & _PAGE_MODIFIED; }
  173. static inline int pte_young(pte_t pte) { return pte.pte_low & _PAGE_ACCESSED; }
  174. static inline int pte_file(pte_t pte) { return pte.pte_low & _PAGE_FILE; }
  175. static inline pte_t pte_wrprotect(pte_t pte)
  176. {
  177. pte.pte_low &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
  178. pte.pte_high &= ~_PAGE_SILENT_WRITE;
  179. return pte;
  180. }
  181. static inline pte_t pte_mkclean(pte_t pte)
  182. {
  183. pte.pte_low &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
  184. pte.pte_high &= ~_PAGE_SILENT_WRITE;
  185. return pte;
  186. }
  187. static inline pte_t pte_mkold(pte_t pte)
  188. {
  189. pte.pte_low &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
  190. pte.pte_high &= ~_PAGE_SILENT_READ;
  191. return pte;
  192. }
  193. static inline pte_t pte_mkwrite(pte_t pte)
  194. {
  195. pte.pte_low |= _PAGE_WRITE;
  196. if (pte.pte_low & _PAGE_MODIFIED) {
  197. pte.pte_low |= _PAGE_SILENT_WRITE;
  198. pte.pte_high |= _PAGE_SILENT_WRITE;
  199. }
  200. return pte;
  201. }
  202. static inline pte_t pte_mkdirty(pte_t pte)
  203. {
  204. pte.pte_low |= _PAGE_MODIFIED;
  205. if (pte.pte_low & _PAGE_WRITE) {
  206. pte.pte_low |= _PAGE_SILENT_WRITE;
  207. pte.pte_high |= _PAGE_SILENT_WRITE;
  208. }
  209. return pte;
  210. }
  211. static inline pte_t pte_mkyoung(pte_t pte)
  212. {
  213. pte.pte_low |= _PAGE_ACCESSED;
  214. if (pte.pte_low & _PAGE_READ) {
  215. pte.pte_low |= _PAGE_SILENT_READ;
  216. pte.pte_high |= _PAGE_SILENT_READ;
  217. }
  218. return pte;
  219. }
  220. #else
  221. static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
  222. static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_MODIFIED; }
  223. static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
  224. static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
  225. static inline pte_t pte_wrprotect(pte_t pte)
  226. {
  227. pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
  228. return pte;
  229. }
  230. static inline pte_t pte_mkclean(pte_t pte)
  231. {
  232. pte_val(pte) &= ~(_PAGE_MODIFIED|_PAGE_SILENT_WRITE);
  233. return pte;
  234. }
  235. static inline pte_t pte_mkold(pte_t pte)
  236. {
  237. pte_val(pte) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
  238. return pte;
  239. }
  240. static inline pte_t pte_mkwrite(pte_t pte)
  241. {
  242. pte_val(pte) |= _PAGE_WRITE;
  243. if (pte_val(pte) & _PAGE_MODIFIED)
  244. pte_val(pte) |= _PAGE_SILENT_WRITE;
  245. return pte;
  246. }
  247. static inline pte_t pte_mkdirty(pte_t pte)
  248. {
  249. pte_val(pte) |= _PAGE_MODIFIED;
  250. if (pte_val(pte) & _PAGE_WRITE)
  251. pte_val(pte) |= _PAGE_SILENT_WRITE;
  252. return pte;
  253. }
  254. static inline pte_t pte_mkyoung(pte_t pte)
  255. {
  256. pte_val(pte) |= _PAGE_ACCESSED;
  257. if (cpu_has_rixi) {
  258. if (!(pte_val(pte) & _PAGE_NO_READ))
  259. pte_val(pte) |= _PAGE_SILENT_READ;
  260. } else {
  261. if (pte_val(pte) & _PAGE_READ)
  262. pte_val(pte) |= _PAGE_SILENT_READ;
  263. }
  264. return pte;
  265. }
  266. #ifdef _PAGE_HUGE
  267. static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE; }
  268. static inline pte_t pte_mkhuge(pte_t pte)
  269. {
  270. pte_val(pte) |= _PAGE_HUGE;
  271. return pte;
  272. }
  273. #endif /* _PAGE_HUGE */
  274. #endif
  275. static inline int pte_special(pte_t pte) { return 0; }
  276. static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
  277. /*
  278. * Macro to make mark a page protection value as "uncacheable". Note
  279. * that "protection" is really a misnomer here as the protection value
  280. * contains the memory attribute bits, dirty bits, and various other
  281. * bits as well.
  282. */
  283. #define pgprot_noncached pgprot_noncached
  284. static inline pgprot_t pgprot_noncached(pgprot_t _prot)
  285. {
  286. unsigned long prot = pgprot_val(_prot);
  287. prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
  288. return __pgprot(prot);
  289. }
  290. /*
  291. * Conversion functions: convert a page and protection to a page entry,
  292. * and a page entry and page directory to the page they refer to.
  293. */
  294. #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
  295. #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
  296. static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
  297. {
  298. pte.pte_low &= _PAGE_CHG_MASK;
  299. pte.pte_high &= ~0x3f;
  300. pte.pte_low |= pgprot_val(newprot);
  301. pte.pte_high |= pgprot_val(newprot) & 0x3f;
  302. return pte;
  303. }
  304. #else
  305. static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
  306. {
  307. return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot));
  308. }
  309. #endif
  310. extern void __update_tlb(struct vm_area_struct *vma, unsigned long address,
  311. pte_t pte);
  312. extern void __update_cache(struct vm_area_struct *vma, unsigned long address,
  313. pte_t pte);
  314. static inline void update_mmu_cache(struct vm_area_struct *vma,
  315. unsigned long address, pte_t *ptep)
  316. {
  317. pte_t pte = *ptep;
  318. __update_tlb(vma, address, pte);
  319. __update_cache(vma, address, pte);
  320. }
  321. static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
  322. unsigned long address, pmd_t *pmdp)
  323. {
  324. pte_t pte = *(pte_t *)pmdp;
  325. __update_tlb(vma, address, pte);
  326. }
  327. #define kern_addr_valid(addr) (1)
  328. #ifdef CONFIG_64BIT_PHYS_ADDR
  329. extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long pfn, unsigned long size, pgprot_t prot);
  330. static inline int io_remap_pfn_range(struct vm_area_struct *vma,
  331. unsigned long vaddr,
  332. unsigned long pfn,
  333. unsigned long size,
  334. pgprot_t prot)
  335. {
  336. phys_t phys_addr_high = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
  337. return remap_pfn_range(vma, vaddr, phys_addr_high >> PAGE_SHIFT, size, prot);
  338. }
  339. #define io_remap_pfn_range io_remap_pfn_range
  340. #endif
  341. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  342. extern int has_transparent_hugepage(void);
  343. static inline int pmd_trans_huge(pmd_t pmd)
  344. {
  345. return !!(pmd_val(pmd) & _PAGE_HUGE);
  346. }
  347. static inline pmd_t pmd_mkhuge(pmd_t pmd)
  348. {
  349. pmd_val(pmd) |= _PAGE_HUGE;
  350. return pmd;
  351. }
  352. static inline int pmd_trans_splitting(pmd_t pmd)
  353. {
  354. return !!(pmd_val(pmd) & _PAGE_SPLITTING);
  355. }
  356. static inline pmd_t pmd_mksplitting(pmd_t pmd)
  357. {
  358. pmd_val(pmd) |= _PAGE_SPLITTING;
  359. return pmd;
  360. }
  361. extern void set_pmd_at(struct mm_struct *mm, unsigned long addr,
  362. pmd_t *pmdp, pmd_t pmd);
  363. #define __HAVE_ARCH_PMDP_SPLITTING_FLUSH
  364. /* Extern to avoid header file madness */
  365. extern void pmdp_splitting_flush(struct vm_area_struct *vma,
  366. unsigned long address,
  367. pmd_t *pmdp);
  368. #define __HAVE_ARCH_PMD_WRITE
  369. static inline int pmd_write(pmd_t pmd)
  370. {
  371. return !!(pmd_val(pmd) & _PAGE_WRITE);
  372. }
  373. static inline pmd_t pmd_wrprotect(pmd_t pmd)
  374. {
  375. pmd_val(pmd) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
  376. return pmd;
  377. }
  378. static inline pmd_t pmd_mkwrite(pmd_t pmd)
  379. {
  380. pmd_val(pmd) |= _PAGE_WRITE;
  381. if (pmd_val(pmd) & _PAGE_MODIFIED)
  382. pmd_val(pmd) |= _PAGE_SILENT_WRITE;
  383. return pmd;
  384. }
  385. static inline int pmd_dirty(pmd_t pmd)
  386. {
  387. return !!(pmd_val(pmd) & _PAGE_MODIFIED);
  388. }
  389. static inline pmd_t pmd_mkclean(pmd_t pmd)
  390. {
  391. pmd_val(pmd) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE);
  392. return pmd;
  393. }
  394. static inline pmd_t pmd_mkdirty(pmd_t pmd)
  395. {
  396. pmd_val(pmd) |= _PAGE_MODIFIED;
  397. if (pmd_val(pmd) & _PAGE_WRITE)
  398. pmd_val(pmd) |= _PAGE_SILENT_WRITE;
  399. return pmd;
  400. }
  401. static inline int pmd_young(pmd_t pmd)
  402. {
  403. return !!(pmd_val(pmd) & _PAGE_ACCESSED);
  404. }
  405. static inline pmd_t pmd_mkold(pmd_t pmd)
  406. {
  407. pmd_val(pmd) &= ~(_PAGE_ACCESSED|_PAGE_SILENT_READ);
  408. return pmd;
  409. }
  410. static inline pmd_t pmd_mkyoung(pmd_t pmd)
  411. {
  412. pmd_val(pmd) |= _PAGE_ACCESSED;
  413. if (cpu_has_rixi) {
  414. if (!(pmd_val(pmd) & _PAGE_NO_READ))
  415. pmd_val(pmd) |= _PAGE_SILENT_READ;
  416. } else {
  417. if (pmd_val(pmd) & _PAGE_READ)
  418. pmd_val(pmd) |= _PAGE_SILENT_READ;
  419. }
  420. return pmd;
  421. }
  422. /* Extern to avoid header file madness */
  423. extern pmd_t mk_pmd(struct page *page, pgprot_t prot);
  424. static inline unsigned long pmd_pfn(pmd_t pmd)
  425. {
  426. return pmd_val(pmd) >> _PFN_SHIFT;
  427. }
  428. static inline struct page *pmd_page(pmd_t pmd)
  429. {
  430. if (pmd_trans_huge(pmd))
  431. return pfn_to_page(pmd_pfn(pmd));
  432. return pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT);
  433. }
  434. static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
  435. {
  436. pmd_val(pmd) = (pmd_val(pmd) & _PAGE_CHG_MASK) | pgprot_val(newprot);
  437. return pmd;
  438. }
  439. static inline pmd_t pmd_mknotpresent(pmd_t pmd)
  440. {
  441. pmd_val(pmd) &= ~(_PAGE_PRESENT | _PAGE_VALID | _PAGE_DIRTY);
  442. return pmd;
  443. }
  444. /*
  445. * The generic version pmdp_get_and_clear uses a version of pmd_clear() with a
  446. * different prototype.
  447. */
  448. #define __HAVE_ARCH_PMDP_GET_AND_CLEAR
  449. static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
  450. unsigned long address, pmd_t *pmdp)
  451. {
  452. pmd_t old = *pmdp;
  453. pmd_clear(pmdp);
  454. return old;
  455. }
  456. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  457. #include <asm-generic/pgtable.h>
  458. /*
  459. * uncached accelerated TLB map for video memory access
  460. */
  461. #ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
  462. #define __HAVE_PHYS_MEM_ACCESS_PROT
  463. struct file;
  464. pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  465. unsigned long size, pgprot_t vma_prot);
  466. int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn,
  467. unsigned long size, pgprot_t *vma_prot);
  468. #endif
  469. /*
  470. * We provide our own get_unmapped area to cope with the virtual aliasing
  471. * constraints placed on us by the cache architecture.
  472. */
  473. #define HAVE_ARCH_UNMAPPED_AREA
  474. #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
  475. /*
  476. * No page table caches to initialise
  477. */
  478. #define pgtable_cache_init() do { } while (0)
  479. #endif /* _ASM_PGTABLE_H */