pgtable.h 20 KB

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  1. #ifndef _ASM_GENERIC_PGTABLE_H
  2. #define _ASM_GENERIC_PGTABLE_H
  3. #ifndef __ASSEMBLY__
  4. #ifdef CONFIG_MMU
  5. #include <linux/mm_types.h>
  6. #include <linux/bug.h>
  7. /*
  8. * On almost all architectures and configurations, 0 can be used as the
  9. * upper ceiling to free_pgtables(): on many architectures it has the same
  10. * effect as using TASK_SIZE. However, there is one configuration which
  11. * must impose a more careful limit, to avoid freeing kernel pgtables.
  12. */
  13. #ifndef USER_PGTABLES_CEILING
  14. #define USER_PGTABLES_CEILING 0UL
  15. #endif
  16. #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
  17. extern int ptep_set_access_flags(struct vm_area_struct *vma,
  18. unsigned long address, pte_t *ptep,
  19. pte_t entry, int dirty);
  20. #endif
  21. #ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
  22. extern int pmdp_set_access_flags(struct vm_area_struct *vma,
  23. unsigned long address, pmd_t *pmdp,
  24. pmd_t entry, int dirty);
  25. #endif
  26. #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
  27. static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
  28. unsigned long address,
  29. pte_t *ptep)
  30. {
  31. pte_t pte = *ptep;
  32. int r = 1;
  33. if (!pte_young(pte))
  34. r = 0;
  35. else
  36. set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte));
  37. return r;
  38. }
  39. #endif
  40. #ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
  41. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  42. static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
  43. unsigned long address,
  44. pmd_t *pmdp)
  45. {
  46. pmd_t pmd = *pmdp;
  47. int r = 1;
  48. if (!pmd_young(pmd))
  49. r = 0;
  50. else
  51. set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));
  52. return r;
  53. }
  54. #else /* CONFIG_TRANSPARENT_HUGEPAGE */
  55. static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
  56. unsigned long address,
  57. pmd_t *pmdp)
  58. {
  59. BUG();
  60. return 0;
  61. }
  62. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  63. #endif
  64. #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
  65. int ptep_clear_flush_young(struct vm_area_struct *vma,
  66. unsigned long address, pte_t *ptep);
  67. #endif
  68. #ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
  69. int pmdp_clear_flush_young(struct vm_area_struct *vma,
  70. unsigned long address, pmd_t *pmdp);
  71. #endif
  72. #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
  73. static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
  74. unsigned long address,
  75. pte_t *ptep)
  76. {
  77. pte_t pte = *ptep;
  78. pte_clear(mm, address, ptep);
  79. return pte;
  80. }
  81. #endif
  82. #ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR
  83. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  84. static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
  85. unsigned long address,
  86. pmd_t *pmdp)
  87. {
  88. pmd_t pmd = *pmdp;
  89. pmd_clear(pmdp);
  90. return pmd;
  91. }
  92. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  93. #endif
  94. #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
  95. static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
  96. unsigned long address, pte_t *ptep,
  97. int full)
  98. {
  99. pte_t pte;
  100. pte = ptep_get_and_clear(mm, address, ptep);
  101. return pte;
  102. }
  103. #endif
  104. /*
  105. * Some architectures may be able to avoid expensive synchronization
  106. * primitives when modifications are made to PTE's which are already
  107. * not present, or in the process of an address space destruction.
  108. */
  109. #ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL
  110. static inline void pte_clear_not_present_full(struct mm_struct *mm,
  111. unsigned long address,
  112. pte_t *ptep,
  113. int full)
  114. {
  115. pte_clear(mm, address, ptep);
  116. }
  117. #endif
  118. #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
  119. extern pte_t ptep_clear_flush(struct vm_area_struct *vma,
  120. unsigned long address,
  121. pte_t *ptep);
  122. #endif
  123. #ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
  124. extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
  125. unsigned long address,
  126. pmd_t *pmdp);
  127. #endif
  128. #ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
  129. struct mm_struct;
  130. static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
  131. {
  132. pte_t old_pte = *ptep;
  133. set_pte_at(mm, address, ptep, pte_wrprotect(old_pte));
  134. }
  135. #endif
  136. #ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT
  137. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  138. static inline void pmdp_set_wrprotect(struct mm_struct *mm,
  139. unsigned long address, pmd_t *pmdp)
  140. {
  141. pmd_t old_pmd = *pmdp;
  142. set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd));
  143. }
  144. #else /* CONFIG_TRANSPARENT_HUGEPAGE */
  145. static inline void pmdp_set_wrprotect(struct mm_struct *mm,
  146. unsigned long address, pmd_t *pmdp)
  147. {
  148. BUG();
  149. }
  150. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  151. #endif
  152. #ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
  153. extern void pmdp_splitting_flush(struct vm_area_struct *vma,
  154. unsigned long address, pmd_t *pmdp);
  155. #endif
  156. #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
  157. extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
  158. pgtable_t pgtable);
  159. #endif
  160. #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW
  161. extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
  162. #endif
  163. #ifndef __HAVE_ARCH_PMDP_INVALIDATE
  164. extern void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
  165. pmd_t *pmdp);
  166. #endif
  167. #ifndef __HAVE_ARCH_PTE_SAME
  168. static inline int pte_same(pte_t pte_a, pte_t pte_b)
  169. {
  170. return pte_val(pte_a) == pte_val(pte_b);
  171. }
  172. #endif
  173. #ifndef __HAVE_ARCH_PMD_SAME
  174. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  175. static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
  176. {
  177. return pmd_val(pmd_a) == pmd_val(pmd_b);
  178. }
  179. #else /* CONFIG_TRANSPARENT_HUGEPAGE */
  180. static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
  181. {
  182. BUG();
  183. return 0;
  184. }
  185. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  186. #endif
  187. #ifndef __HAVE_ARCH_PGD_OFFSET_GATE
  188. #define pgd_offset_gate(mm, addr) pgd_offset(mm, addr)
  189. #endif
  190. #ifndef __HAVE_ARCH_MOVE_PTE
  191. #define move_pte(pte, prot, old_addr, new_addr) (pte)
  192. #endif
  193. #ifndef pte_accessible
  194. # define pte_accessible(pte) ((void)(pte),1)
  195. #endif
  196. #ifndef flush_tlb_fix_spurious_fault
  197. #define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)
  198. #endif
  199. #ifndef pgprot_noncached
  200. #define pgprot_noncached(prot) (prot)
  201. #endif
  202. #ifndef pgprot_writecombine
  203. #define pgprot_writecombine pgprot_noncached
  204. #endif
  205. /*
  206. * When walking page tables, get the address of the next boundary,
  207. * or the end address of the range if that comes earlier. Although no
  208. * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
  209. */
  210. #define pgd_addr_end(addr, end) \
  211. ({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \
  212. (__boundary - 1 < (end) - 1)? __boundary: (end); \
  213. })
  214. #ifndef pud_addr_end
  215. #define pud_addr_end(addr, end) \
  216. ({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \
  217. (__boundary - 1 < (end) - 1)? __boundary: (end); \
  218. })
  219. #endif
  220. #ifndef pmd_addr_end
  221. #define pmd_addr_end(addr, end) \
  222. ({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \
  223. (__boundary - 1 < (end) - 1)? __boundary: (end); \
  224. })
  225. #endif
  226. /*
  227. * When walking page tables, we usually want to skip any p?d_none entries;
  228. * and any p?d_bad entries - reporting the error before resetting to none.
  229. * Do the tests inline, but report and clear the bad entry in mm/memory.c.
  230. */
  231. void pgd_clear_bad(pgd_t *);
  232. void pud_clear_bad(pud_t *);
  233. void pmd_clear_bad(pmd_t *);
  234. static inline int pgd_none_or_clear_bad(pgd_t *pgd)
  235. {
  236. if (pgd_none(*pgd))
  237. return 1;
  238. if (unlikely(pgd_bad(*pgd))) {
  239. pgd_clear_bad(pgd);
  240. return 1;
  241. }
  242. return 0;
  243. }
  244. static inline int pud_none_or_clear_bad(pud_t *pud)
  245. {
  246. if (pud_none(*pud))
  247. return 1;
  248. if (unlikely(pud_bad(*pud))) {
  249. pud_clear_bad(pud);
  250. return 1;
  251. }
  252. return 0;
  253. }
  254. static inline int pmd_none_or_clear_bad(pmd_t *pmd)
  255. {
  256. if (pmd_none(*pmd))
  257. return 1;
  258. if (unlikely(pmd_bad(*pmd))) {
  259. pmd_clear_bad(pmd);
  260. return 1;
  261. }
  262. return 0;
  263. }
  264. static inline pte_t __ptep_modify_prot_start(struct mm_struct *mm,
  265. unsigned long addr,
  266. pte_t *ptep)
  267. {
  268. /*
  269. * Get the current pte state, but zero it out to make it
  270. * non-present, preventing the hardware from asynchronously
  271. * updating it.
  272. */
  273. return ptep_get_and_clear(mm, addr, ptep);
  274. }
  275. static inline void __ptep_modify_prot_commit(struct mm_struct *mm,
  276. unsigned long addr,
  277. pte_t *ptep, pte_t pte)
  278. {
  279. /*
  280. * The pte is non-present, so there's no hardware state to
  281. * preserve.
  282. */
  283. set_pte_at(mm, addr, ptep, pte);
  284. }
  285. #ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
  286. /*
  287. * Start a pte protection read-modify-write transaction, which
  288. * protects against asynchronous hardware modifications to the pte.
  289. * The intention is not to prevent the hardware from making pte
  290. * updates, but to prevent any updates it may make from being lost.
  291. *
  292. * This does not protect against other software modifications of the
  293. * pte; the appropriate pte lock must be held over the transation.
  294. *
  295. * Note that this interface is intended to be batchable, meaning that
  296. * ptep_modify_prot_commit may not actually update the pte, but merely
  297. * queue the update to be done at some later time. The update must be
  298. * actually committed before the pte lock is released, however.
  299. */
  300. static inline pte_t ptep_modify_prot_start(struct mm_struct *mm,
  301. unsigned long addr,
  302. pte_t *ptep)
  303. {
  304. return __ptep_modify_prot_start(mm, addr, ptep);
  305. }
  306. /*
  307. * Commit an update to a pte, leaving any hardware-controlled bits in
  308. * the PTE unmodified.
  309. */
  310. static inline void ptep_modify_prot_commit(struct mm_struct *mm,
  311. unsigned long addr,
  312. pte_t *ptep, pte_t pte)
  313. {
  314. __ptep_modify_prot_commit(mm, addr, ptep, pte);
  315. }
  316. #endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */
  317. #endif /* CONFIG_MMU */
  318. /*
  319. * A facility to provide lazy MMU batching. This allows PTE updates and
  320. * page invalidations to be delayed until a call to leave lazy MMU mode
  321. * is issued. Some architectures may benefit from doing this, and it is
  322. * beneficial for both shadow and direct mode hypervisors, which may batch
  323. * the PTE updates which happen during this window. Note that using this
  324. * interface requires that read hazards be removed from the code. A read
  325. * hazard could result in the direct mode hypervisor case, since the actual
  326. * write to the page tables may not yet have taken place, so reads though
  327. * a raw PTE pointer after it has been modified are not guaranteed to be
  328. * up to date. This mode can only be entered and left under the protection of
  329. * the page table locks for all page tables which may be modified. In the UP
  330. * case, this is required so that preemption is disabled, and in the SMP case,
  331. * it must synchronize the delayed page table writes properly on other CPUs.
  332. */
  333. #ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE
  334. #define arch_enter_lazy_mmu_mode() do {} while (0)
  335. #define arch_leave_lazy_mmu_mode() do {} while (0)
  336. #define arch_flush_lazy_mmu_mode() do {} while (0)
  337. #endif
  338. /*
  339. * A facility to provide batching of the reload of page tables and
  340. * other process state with the actual context switch code for
  341. * paravirtualized guests. By convention, only one of the batched
  342. * update (lazy) modes (CPU, MMU) should be active at any given time,
  343. * entry should never be nested, and entry and exits should always be
  344. * paired. This is for sanity of maintaining and reasoning about the
  345. * kernel code. In this case, the exit (end of the context switch) is
  346. * in architecture-specific code, and so doesn't need a generic
  347. * definition.
  348. */
  349. #ifndef __HAVE_ARCH_START_CONTEXT_SWITCH
  350. #define arch_start_context_switch(prev) do {} while (0)
  351. #endif
  352. #ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY
  353. static inline int pte_soft_dirty(pte_t pte)
  354. {
  355. return 0;
  356. }
  357. static inline int pmd_soft_dirty(pmd_t pmd)
  358. {
  359. return 0;
  360. }
  361. static inline pte_t pte_mksoft_dirty(pte_t pte)
  362. {
  363. return pte;
  364. }
  365. static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
  366. {
  367. return pmd;
  368. }
  369. static inline pte_t pte_swp_mksoft_dirty(pte_t pte)
  370. {
  371. return pte;
  372. }
  373. static inline int pte_swp_soft_dirty(pte_t pte)
  374. {
  375. return 0;
  376. }
  377. static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
  378. {
  379. return pte;
  380. }
  381. static inline pte_t pte_file_clear_soft_dirty(pte_t pte)
  382. {
  383. return pte;
  384. }
  385. static inline pte_t pte_file_mksoft_dirty(pte_t pte)
  386. {
  387. return pte;
  388. }
  389. static inline int pte_file_soft_dirty(pte_t pte)
  390. {
  391. return 0;
  392. }
  393. #endif
  394. #ifndef __HAVE_PFNMAP_TRACKING
  395. /*
  396. * Interfaces that can be used by architecture code to keep track of
  397. * memory type of pfn mappings specified by the remap_pfn_range,
  398. * vm_insert_pfn.
  399. */
  400. /*
  401. * track_pfn_remap is called when a _new_ pfn mapping is being established
  402. * by remap_pfn_range() for physical range indicated by pfn and size.
  403. */
  404. static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
  405. unsigned long pfn, unsigned long addr,
  406. unsigned long size)
  407. {
  408. return 0;
  409. }
  410. /*
  411. * track_pfn_insert is called when a _new_ single pfn is established
  412. * by vm_insert_pfn().
  413. */
  414. static inline int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
  415. unsigned long pfn)
  416. {
  417. return 0;
  418. }
  419. /*
  420. * track_pfn_copy is called when vma that is covering the pfnmap gets
  421. * copied through copy_page_range().
  422. */
  423. static inline int track_pfn_copy(struct vm_area_struct *vma)
  424. {
  425. return 0;
  426. }
  427. /*
  428. * untrack_pfn_vma is called while unmapping a pfnmap for a region.
  429. * untrack can be called for a specific region indicated by pfn and size or
  430. * can be for the entire vma (in which case pfn, size are zero).
  431. */
  432. static inline void untrack_pfn(struct vm_area_struct *vma,
  433. unsigned long pfn, unsigned long size)
  434. {
  435. }
  436. #else
  437. extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
  438. unsigned long pfn, unsigned long addr,
  439. unsigned long size);
  440. extern int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
  441. unsigned long pfn);
  442. extern int track_pfn_copy(struct vm_area_struct *vma);
  443. extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
  444. unsigned long size);
  445. #endif
  446. #ifdef __HAVE_COLOR_ZERO_PAGE
  447. static inline int is_zero_pfn(unsigned long pfn)
  448. {
  449. extern unsigned long zero_pfn;
  450. unsigned long offset_from_zero_pfn = pfn - zero_pfn;
  451. return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
  452. }
  453. #define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr))
  454. #else
  455. static inline int is_zero_pfn(unsigned long pfn)
  456. {
  457. extern unsigned long zero_pfn;
  458. return pfn == zero_pfn;
  459. }
  460. static inline unsigned long my_zero_pfn(unsigned long addr)
  461. {
  462. extern unsigned long zero_pfn;
  463. return zero_pfn;
  464. }
  465. #endif
  466. #ifdef CONFIG_MMU
  467. #ifndef CONFIG_TRANSPARENT_HUGEPAGE
  468. static inline int pmd_trans_huge(pmd_t pmd)
  469. {
  470. return 0;
  471. }
  472. static inline int pmd_trans_splitting(pmd_t pmd)
  473. {
  474. return 0;
  475. }
  476. #ifndef __HAVE_ARCH_PMD_WRITE
  477. static inline int pmd_write(pmd_t pmd)
  478. {
  479. BUG();
  480. return 0;
  481. }
  482. #endif /* __HAVE_ARCH_PMD_WRITE */
  483. #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
  484. #ifndef pmd_read_atomic
  485. static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
  486. {
  487. /*
  488. * Depend on compiler for an atomic pmd read. NOTE: this is
  489. * only going to work, if the pmdval_t isn't larger than
  490. * an unsigned long.
  491. */
  492. return *pmdp;
  493. }
  494. #endif
  495. /*
  496. * This function is meant to be used by sites walking pagetables with
  497. * the mmap_sem hold in read mode to protect against MADV_DONTNEED and
  498. * transhuge page faults. MADV_DONTNEED can convert a transhuge pmd
  499. * into a null pmd and the transhuge page fault can convert a null pmd
  500. * into an hugepmd or into a regular pmd (if the hugepage allocation
  501. * fails). While holding the mmap_sem in read mode the pmd becomes
  502. * stable and stops changing under us only if it's not null and not a
  503. * transhuge pmd. When those races occurs and this function makes a
  504. * difference vs the standard pmd_none_or_clear_bad, the result is
  505. * undefined so behaving like if the pmd was none is safe (because it
  506. * can return none anyway). The compiler level barrier() is critically
  507. * important to compute the two checks atomically on the same pmdval.
  508. *
  509. * For 32bit kernels with a 64bit large pmd_t this automatically takes
  510. * care of reading the pmd atomically to avoid SMP race conditions
  511. * against pmd_populate() when the mmap_sem is hold for reading by the
  512. * caller (a special atomic read not done by "gcc" as in the generic
  513. * version above, is also needed when THP is disabled because the page
  514. * fault can populate the pmd from under us).
  515. */
  516. static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd)
  517. {
  518. pmd_t pmdval = pmd_read_atomic(pmd);
  519. /*
  520. * The barrier will stabilize the pmdval in a register or on
  521. * the stack so that it will stop changing under the code.
  522. *
  523. * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE,
  524. * pmd_read_atomic is allowed to return a not atomic pmdval
  525. * (for example pointing to an hugepage that has never been
  526. * mapped in the pmd). The below checks will only care about
  527. * the low part of the pmd with 32bit PAE x86 anyway, with the
  528. * exception of pmd_none(). So the important thing is that if
  529. * the low part of the pmd is found null, the high part will
  530. * be also null or the pmd_none() check below would be
  531. * confused.
  532. */
  533. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  534. barrier();
  535. #endif
  536. if (pmd_none(pmdval))
  537. return 1;
  538. if (unlikely(pmd_bad(pmdval))) {
  539. if (!pmd_trans_huge(pmdval))
  540. pmd_clear_bad(pmd);
  541. return 1;
  542. }
  543. return 0;
  544. }
  545. /*
  546. * This is a noop if Transparent Hugepage Support is not built into
  547. * the kernel. Otherwise it is equivalent to
  548. * pmd_none_or_trans_huge_or_clear_bad(), and shall only be called in
  549. * places that already verified the pmd is not none and they want to
  550. * walk ptes while holding the mmap sem in read mode (write mode don't
  551. * need this). If THP is not enabled, the pmd can't go away under the
  552. * code even if MADV_DONTNEED runs, but if THP is enabled we need to
  553. * run a pmd_trans_unstable before walking the ptes after
  554. * split_huge_page_pmd returns (because it may have run when the pmd
  555. * become null, but then a page fault can map in a THP and not a
  556. * regular page).
  557. */
  558. static inline int pmd_trans_unstable(pmd_t *pmd)
  559. {
  560. #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  561. return pmd_none_or_trans_huge_or_clear_bad(pmd);
  562. #else
  563. return 0;
  564. #endif
  565. }
  566. #ifdef CONFIG_NUMA_BALANCING
  567. #ifdef CONFIG_ARCH_USES_NUMA_PROT_NONE
  568. /*
  569. * _PAGE_NUMA works identical to _PAGE_PROTNONE (it's actually the
  570. * same bit too). It's set only when _PAGE_PRESET is not set and it's
  571. * never set if _PAGE_PRESENT is set.
  572. *
  573. * pte/pmd_present() returns true if pte/pmd_numa returns true. Page
  574. * fault triggers on those regions if pte/pmd_numa returns true
  575. * (because _PAGE_PRESENT is not set).
  576. */
  577. #ifndef pte_numa
  578. static inline int pte_numa(pte_t pte)
  579. {
  580. return (pte_flags(pte) &
  581. (_PAGE_NUMA|_PAGE_PRESENT)) == _PAGE_NUMA;
  582. }
  583. #endif
  584. #ifndef pmd_numa
  585. static inline int pmd_numa(pmd_t pmd)
  586. {
  587. return (pmd_flags(pmd) &
  588. (_PAGE_NUMA|_PAGE_PRESENT)) == _PAGE_NUMA;
  589. }
  590. #endif
  591. /*
  592. * pte/pmd_mknuma sets the _PAGE_ACCESSED bitflag automatically
  593. * because they're called by the NUMA hinting minor page fault. If we
  594. * wouldn't set the _PAGE_ACCESSED bitflag here, the TLB miss handler
  595. * would be forced to set it later while filling the TLB after we
  596. * return to userland. That would trigger a second write to memory
  597. * that we optimize away by setting _PAGE_ACCESSED here.
  598. */
  599. #ifndef pte_mknonnuma
  600. static inline pte_t pte_mknonnuma(pte_t pte)
  601. {
  602. pte = pte_clear_flags(pte, _PAGE_NUMA);
  603. return pte_set_flags(pte, _PAGE_PRESENT|_PAGE_ACCESSED);
  604. }
  605. #endif
  606. #ifndef pmd_mknonnuma
  607. static inline pmd_t pmd_mknonnuma(pmd_t pmd)
  608. {
  609. pmd = pmd_clear_flags(pmd, _PAGE_NUMA);
  610. return pmd_set_flags(pmd, _PAGE_PRESENT|_PAGE_ACCESSED);
  611. }
  612. #endif
  613. #ifndef pte_mknuma
  614. static inline pte_t pte_mknuma(pte_t pte)
  615. {
  616. pte = pte_set_flags(pte, _PAGE_NUMA);
  617. return pte_clear_flags(pte, _PAGE_PRESENT);
  618. }
  619. #endif
  620. #ifndef pmd_mknuma
  621. static inline pmd_t pmd_mknuma(pmd_t pmd)
  622. {
  623. pmd = pmd_set_flags(pmd, _PAGE_NUMA);
  624. return pmd_clear_flags(pmd, _PAGE_PRESENT);
  625. }
  626. #endif
  627. #else
  628. extern int pte_numa(pte_t pte);
  629. extern int pmd_numa(pmd_t pmd);
  630. extern pte_t pte_mknonnuma(pte_t pte);
  631. extern pmd_t pmd_mknonnuma(pmd_t pmd);
  632. extern pte_t pte_mknuma(pte_t pte);
  633. extern pmd_t pmd_mknuma(pmd_t pmd);
  634. #endif /* CONFIG_ARCH_USES_NUMA_PROT_NONE */
  635. #else
  636. static inline int pmd_numa(pmd_t pmd)
  637. {
  638. return 0;
  639. }
  640. static inline int pte_numa(pte_t pte)
  641. {
  642. return 0;
  643. }
  644. static inline pte_t pte_mknonnuma(pte_t pte)
  645. {
  646. return pte;
  647. }
  648. static inline pmd_t pmd_mknonnuma(pmd_t pmd)
  649. {
  650. return pmd;
  651. }
  652. static inline pte_t pte_mknuma(pte_t pte)
  653. {
  654. return pte;
  655. }
  656. static inline pmd_t pmd_mknuma(pmd_t pmd)
  657. {
  658. return pmd;
  659. }
  660. #endif /* CONFIG_NUMA_BALANCING */
  661. #endif /* CONFIG_MMU */
  662. #endif /* !__ASSEMBLY__ */
  663. #ifndef io_remap_pfn_range
  664. #define io_remap_pfn_range remap_pfn_range
  665. #endif
  666. #endif /* _ASM_GENERIC_PGTABLE_H */