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