at v3.18 22 kB view raw
1#ifndef _ASM_GENERIC_PGTABLE_H 2#define _ASM_GENERIC_PGTABLE_H 3 4#ifndef __ASSEMBLY__ 5#ifdef CONFIG_MMU 6 7#include <linux/mm_types.h> 8#include <linux/bug.h> 9 10/* 11 * On almost all architectures and configurations, 0 can be used as the 12 * upper ceiling to free_pgtables(): on many architectures it has the same 13 * effect as using TASK_SIZE. However, there is one configuration which 14 * must impose a more careful limit, to avoid freeing kernel pgtables. 15 */ 16#ifndef USER_PGTABLES_CEILING 17#define USER_PGTABLES_CEILING 0UL 18#endif 19 20#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS 21extern int ptep_set_access_flags(struct vm_area_struct *vma, 22 unsigned long address, pte_t *ptep, 23 pte_t entry, int dirty); 24#endif 25 26#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS 27extern int pmdp_set_access_flags(struct vm_area_struct *vma, 28 unsigned long address, pmd_t *pmdp, 29 pmd_t entry, int dirty); 30#endif 31 32#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG 33static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, 34 unsigned long address, 35 pte_t *ptep) 36{ 37 pte_t pte = *ptep; 38 int r = 1; 39 if (!pte_young(pte)) 40 r = 0; 41 else 42 set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte)); 43 return r; 44} 45#endif 46 47#ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG 48#ifdef CONFIG_TRANSPARENT_HUGEPAGE 49static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, 50 unsigned long address, 51 pmd_t *pmdp) 52{ 53 pmd_t pmd = *pmdp; 54 int r = 1; 55 if (!pmd_young(pmd)) 56 r = 0; 57 else 58 set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd)); 59 return r; 60} 61#else /* CONFIG_TRANSPARENT_HUGEPAGE */ 62static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, 63 unsigned long address, 64 pmd_t *pmdp) 65{ 66 BUG(); 67 return 0; 68} 69#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 70#endif 71 72#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH 73int ptep_clear_flush_young(struct vm_area_struct *vma, 74 unsigned long address, pte_t *ptep); 75#endif 76 77#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH 78int pmdp_clear_flush_young(struct vm_area_struct *vma, 79 unsigned long address, pmd_t *pmdp); 80#endif 81 82#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR 83static inline pte_t ptep_get_and_clear(struct mm_struct *mm, 84 unsigned long address, 85 pte_t *ptep) 86{ 87 pte_t pte = *ptep; 88 pte_clear(mm, address, ptep); 89 return pte; 90} 91#endif 92 93#ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR 94#ifdef CONFIG_TRANSPARENT_HUGEPAGE 95static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm, 96 unsigned long address, 97 pmd_t *pmdp) 98{ 99 pmd_t pmd = *pmdp; 100 pmd_clear(pmdp); 101 return pmd; 102} 103#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 104#endif 105 106#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL 107static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, 108 unsigned long address, pte_t *ptep, 109 int full) 110{ 111 pte_t pte; 112 pte = ptep_get_and_clear(mm, address, ptep); 113 return pte; 114} 115#endif 116 117/* 118 * Some architectures may be able to avoid expensive synchronization 119 * primitives when modifications are made to PTE's which are already 120 * not present, or in the process of an address space destruction. 121 */ 122#ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL 123static inline void pte_clear_not_present_full(struct mm_struct *mm, 124 unsigned long address, 125 pte_t *ptep, 126 int full) 127{ 128 pte_clear(mm, address, ptep); 129} 130#endif 131 132#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH 133extern pte_t ptep_clear_flush(struct vm_area_struct *vma, 134 unsigned long address, 135 pte_t *ptep); 136#endif 137 138#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH 139extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma, 140 unsigned long address, 141 pmd_t *pmdp); 142#endif 143 144#ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT 145struct mm_struct; 146static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep) 147{ 148 pte_t old_pte = *ptep; 149 set_pte_at(mm, address, ptep, pte_wrprotect(old_pte)); 150} 151#endif 152 153#ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT 154#ifdef CONFIG_TRANSPARENT_HUGEPAGE 155static inline void pmdp_set_wrprotect(struct mm_struct *mm, 156 unsigned long address, pmd_t *pmdp) 157{ 158 pmd_t old_pmd = *pmdp; 159 set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd)); 160} 161#else /* CONFIG_TRANSPARENT_HUGEPAGE */ 162static inline void pmdp_set_wrprotect(struct mm_struct *mm, 163 unsigned long address, pmd_t *pmdp) 164{ 165 BUG(); 166} 167#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 168#endif 169 170#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH 171extern void pmdp_splitting_flush(struct vm_area_struct *vma, 172 unsigned long address, pmd_t *pmdp); 173#endif 174 175#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT 176extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, 177 pgtable_t pgtable); 178#endif 179 180#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW 181extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp); 182#endif 183 184#ifndef __HAVE_ARCH_PMDP_INVALIDATE 185extern void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, 186 pmd_t *pmdp); 187#endif 188 189#ifndef __HAVE_ARCH_PTE_SAME 190static inline int pte_same(pte_t pte_a, pte_t pte_b) 191{ 192 return pte_val(pte_a) == pte_val(pte_b); 193} 194#endif 195 196#ifndef __HAVE_ARCH_PTE_UNUSED 197/* 198 * Some architectures provide facilities to virtualization guests 199 * so that they can flag allocated pages as unused. This allows the 200 * host to transparently reclaim unused pages. This function returns 201 * whether the pte's page is unused. 202 */ 203static inline int pte_unused(pte_t pte) 204{ 205 return 0; 206} 207#endif 208 209#ifndef __HAVE_ARCH_PMD_SAME 210#ifdef CONFIG_TRANSPARENT_HUGEPAGE 211static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) 212{ 213 return pmd_val(pmd_a) == pmd_val(pmd_b); 214} 215#else /* CONFIG_TRANSPARENT_HUGEPAGE */ 216static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) 217{ 218 BUG(); 219 return 0; 220} 221#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 222#endif 223 224#ifndef __HAVE_ARCH_PGD_OFFSET_GATE 225#define pgd_offset_gate(mm, addr) pgd_offset(mm, addr) 226#endif 227 228#ifndef __HAVE_ARCH_MOVE_PTE 229#define move_pte(pte, prot, old_addr, new_addr) (pte) 230#endif 231 232#ifndef pte_accessible 233# define pte_accessible(mm, pte) ((void)(pte), 1) 234#endif 235 236#ifndef pte_present_nonuma 237#define pte_present_nonuma(pte) pte_present(pte) 238#endif 239 240#ifndef flush_tlb_fix_spurious_fault 241#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address) 242#endif 243 244#ifndef pgprot_noncached 245#define pgprot_noncached(prot) (prot) 246#endif 247 248#ifndef pgprot_writecombine 249#define pgprot_writecombine pgprot_noncached 250#endif 251 252#ifndef pgprot_device 253#define pgprot_device pgprot_noncached 254#endif 255 256#ifndef pgprot_modify 257#define pgprot_modify pgprot_modify 258static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) 259{ 260 if (pgprot_val(oldprot) == pgprot_val(pgprot_noncached(oldprot))) 261 newprot = pgprot_noncached(newprot); 262 if (pgprot_val(oldprot) == pgprot_val(pgprot_writecombine(oldprot))) 263 newprot = pgprot_writecombine(newprot); 264 if (pgprot_val(oldprot) == pgprot_val(pgprot_device(oldprot))) 265 newprot = pgprot_device(newprot); 266 return newprot; 267} 268#endif 269 270/* 271 * When walking page tables, get the address of the next boundary, 272 * or the end address of the range if that comes earlier. Although no 273 * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout. 274 */ 275 276#define pgd_addr_end(addr, end) \ 277({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \ 278 (__boundary - 1 < (end) - 1)? __boundary: (end); \ 279}) 280 281#ifndef pud_addr_end 282#define pud_addr_end(addr, end) \ 283({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \ 284 (__boundary - 1 < (end) - 1)? __boundary: (end); \ 285}) 286#endif 287 288#ifndef pmd_addr_end 289#define pmd_addr_end(addr, end) \ 290({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \ 291 (__boundary - 1 < (end) - 1)? __boundary: (end); \ 292}) 293#endif 294 295/* 296 * When walking page tables, we usually want to skip any p?d_none entries; 297 * and any p?d_bad entries - reporting the error before resetting to none. 298 * Do the tests inline, but report and clear the bad entry in mm/memory.c. 299 */ 300void pgd_clear_bad(pgd_t *); 301void pud_clear_bad(pud_t *); 302void pmd_clear_bad(pmd_t *); 303 304static inline int pgd_none_or_clear_bad(pgd_t *pgd) 305{ 306 if (pgd_none(*pgd)) 307 return 1; 308 if (unlikely(pgd_bad(*pgd))) { 309 pgd_clear_bad(pgd); 310 return 1; 311 } 312 return 0; 313} 314 315static inline int pud_none_or_clear_bad(pud_t *pud) 316{ 317 if (pud_none(*pud)) 318 return 1; 319 if (unlikely(pud_bad(*pud))) { 320 pud_clear_bad(pud); 321 return 1; 322 } 323 return 0; 324} 325 326static inline int pmd_none_or_clear_bad(pmd_t *pmd) 327{ 328 if (pmd_none(*pmd)) 329 return 1; 330 if (unlikely(pmd_bad(*pmd))) { 331 pmd_clear_bad(pmd); 332 return 1; 333 } 334 return 0; 335} 336 337static inline pte_t __ptep_modify_prot_start(struct mm_struct *mm, 338 unsigned long addr, 339 pte_t *ptep) 340{ 341 /* 342 * Get the current pte state, but zero it out to make it 343 * non-present, preventing the hardware from asynchronously 344 * updating it. 345 */ 346 return ptep_get_and_clear(mm, addr, ptep); 347} 348 349static inline void __ptep_modify_prot_commit(struct mm_struct *mm, 350 unsigned long addr, 351 pte_t *ptep, pte_t pte) 352{ 353 /* 354 * The pte is non-present, so there's no hardware state to 355 * preserve. 356 */ 357 set_pte_at(mm, addr, ptep, pte); 358} 359 360#ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION 361/* 362 * Start a pte protection read-modify-write transaction, which 363 * protects against asynchronous hardware modifications to the pte. 364 * The intention is not to prevent the hardware from making pte 365 * updates, but to prevent any updates it may make from being lost. 366 * 367 * This does not protect against other software modifications of the 368 * pte; the appropriate pte lock must be held over the transation. 369 * 370 * Note that this interface is intended to be batchable, meaning that 371 * ptep_modify_prot_commit may not actually update the pte, but merely 372 * queue the update to be done at some later time. The update must be 373 * actually committed before the pte lock is released, however. 374 */ 375static inline pte_t ptep_modify_prot_start(struct mm_struct *mm, 376 unsigned long addr, 377 pte_t *ptep) 378{ 379 return __ptep_modify_prot_start(mm, addr, ptep); 380} 381 382/* 383 * Commit an update to a pte, leaving any hardware-controlled bits in 384 * the PTE unmodified. 385 */ 386static inline void ptep_modify_prot_commit(struct mm_struct *mm, 387 unsigned long addr, 388 pte_t *ptep, pte_t pte) 389{ 390 __ptep_modify_prot_commit(mm, addr, ptep, pte); 391} 392#endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */ 393#endif /* CONFIG_MMU */ 394 395/* 396 * A facility to provide lazy MMU batching. This allows PTE updates and 397 * page invalidations to be delayed until a call to leave lazy MMU mode 398 * is issued. Some architectures may benefit from doing this, and it is 399 * beneficial for both shadow and direct mode hypervisors, which may batch 400 * the PTE updates which happen during this window. Note that using this 401 * interface requires that read hazards be removed from the code. A read 402 * hazard could result in the direct mode hypervisor case, since the actual 403 * write to the page tables may not yet have taken place, so reads though 404 * a raw PTE pointer after it has been modified are not guaranteed to be 405 * up to date. This mode can only be entered and left under the protection of 406 * the page table locks for all page tables which may be modified. In the UP 407 * case, this is required so that preemption is disabled, and in the SMP case, 408 * it must synchronize the delayed page table writes properly on other CPUs. 409 */ 410#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE 411#define arch_enter_lazy_mmu_mode() do {} while (0) 412#define arch_leave_lazy_mmu_mode() do {} while (0) 413#define arch_flush_lazy_mmu_mode() do {} while (0) 414#endif 415 416/* 417 * A facility to provide batching of the reload of page tables and 418 * other process state with the actual context switch code for 419 * paravirtualized guests. By convention, only one of the batched 420 * update (lazy) modes (CPU, MMU) should be active at any given time, 421 * entry should never be nested, and entry and exits should always be 422 * paired. This is for sanity of maintaining and reasoning about the 423 * kernel code. In this case, the exit (end of the context switch) is 424 * in architecture-specific code, and so doesn't need a generic 425 * definition. 426 */ 427#ifndef __HAVE_ARCH_START_CONTEXT_SWITCH 428#define arch_start_context_switch(prev) do {} while (0) 429#endif 430 431#ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY 432static inline int pte_soft_dirty(pte_t pte) 433{ 434 return 0; 435} 436 437static inline int pmd_soft_dirty(pmd_t pmd) 438{ 439 return 0; 440} 441 442static inline pte_t pte_mksoft_dirty(pte_t pte) 443{ 444 return pte; 445} 446 447static inline pmd_t pmd_mksoft_dirty(pmd_t pmd) 448{ 449 return pmd; 450} 451 452static inline pte_t pte_swp_mksoft_dirty(pte_t pte) 453{ 454 return pte; 455} 456 457static inline int pte_swp_soft_dirty(pte_t pte) 458{ 459 return 0; 460} 461 462static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) 463{ 464 return pte; 465} 466 467static inline pte_t pte_file_clear_soft_dirty(pte_t pte) 468{ 469 return pte; 470} 471 472static inline pte_t pte_file_mksoft_dirty(pte_t pte) 473{ 474 return pte; 475} 476 477static inline int pte_file_soft_dirty(pte_t pte) 478{ 479 return 0; 480} 481#endif 482 483#ifndef __HAVE_PFNMAP_TRACKING 484/* 485 * Interfaces that can be used by architecture code to keep track of 486 * memory type of pfn mappings specified by the remap_pfn_range, 487 * vm_insert_pfn. 488 */ 489 490/* 491 * track_pfn_remap is called when a _new_ pfn mapping is being established 492 * by remap_pfn_range() for physical range indicated by pfn and size. 493 */ 494static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, 495 unsigned long pfn, unsigned long addr, 496 unsigned long size) 497{ 498 return 0; 499} 500 501/* 502 * track_pfn_insert is called when a _new_ single pfn is established 503 * by vm_insert_pfn(). 504 */ 505static inline int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, 506 unsigned long pfn) 507{ 508 return 0; 509} 510 511/* 512 * track_pfn_copy is called when vma that is covering the pfnmap gets 513 * copied through copy_page_range(). 514 */ 515static inline int track_pfn_copy(struct vm_area_struct *vma) 516{ 517 return 0; 518} 519 520/* 521 * untrack_pfn_vma is called while unmapping a pfnmap for a region. 522 * untrack can be called for a specific region indicated by pfn and size or 523 * can be for the entire vma (in which case pfn, size are zero). 524 */ 525static inline void untrack_pfn(struct vm_area_struct *vma, 526 unsigned long pfn, unsigned long size) 527{ 528} 529#else 530extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, 531 unsigned long pfn, unsigned long addr, 532 unsigned long size); 533extern int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, 534 unsigned long pfn); 535extern int track_pfn_copy(struct vm_area_struct *vma); 536extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, 537 unsigned long size); 538#endif 539 540#ifdef __HAVE_COLOR_ZERO_PAGE 541static inline int is_zero_pfn(unsigned long pfn) 542{ 543 extern unsigned long zero_pfn; 544 unsigned long offset_from_zero_pfn = pfn - zero_pfn; 545 return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); 546} 547 548#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) 549 550#else 551static inline int is_zero_pfn(unsigned long pfn) 552{ 553 extern unsigned long zero_pfn; 554 return pfn == zero_pfn; 555} 556 557static inline unsigned long my_zero_pfn(unsigned long addr) 558{ 559 extern unsigned long zero_pfn; 560 return zero_pfn; 561} 562#endif 563 564#ifdef CONFIG_MMU 565 566#ifndef CONFIG_TRANSPARENT_HUGEPAGE 567static inline int pmd_trans_huge(pmd_t pmd) 568{ 569 return 0; 570} 571static inline int pmd_trans_splitting(pmd_t pmd) 572{ 573 return 0; 574} 575#ifndef __HAVE_ARCH_PMD_WRITE 576static inline int pmd_write(pmd_t pmd) 577{ 578 BUG(); 579 return 0; 580} 581#endif /* __HAVE_ARCH_PMD_WRITE */ 582#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ 583 584#ifndef pmd_read_atomic 585static inline pmd_t pmd_read_atomic(pmd_t *pmdp) 586{ 587 /* 588 * Depend on compiler for an atomic pmd read. NOTE: this is 589 * only going to work, if the pmdval_t isn't larger than 590 * an unsigned long. 591 */ 592 return *pmdp; 593} 594#endif 595 596#ifndef pmd_move_must_withdraw 597static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl, 598 spinlock_t *old_pmd_ptl) 599{ 600 /* 601 * With split pmd lock we also need to move preallocated 602 * PTE page table if new_pmd is on different PMD page table. 603 */ 604 return new_pmd_ptl != old_pmd_ptl; 605} 606#endif 607 608/* 609 * This function is meant to be used by sites walking pagetables with 610 * the mmap_sem hold in read mode to protect against MADV_DONTNEED and 611 * transhuge page faults. MADV_DONTNEED can convert a transhuge pmd 612 * into a null pmd and the transhuge page fault can convert a null pmd 613 * into an hugepmd or into a regular pmd (if the hugepage allocation 614 * fails). While holding the mmap_sem in read mode the pmd becomes 615 * stable and stops changing under us only if it's not null and not a 616 * transhuge pmd. When those races occurs and this function makes a 617 * difference vs the standard pmd_none_or_clear_bad, the result is 618 * undefined so behaving like if the pmd was none is safe (because it 619 * can return none anyway). The compiler level barrier() is critically 620 * important to compute the two checks atomically on the same pmdval. 621 * 622 * For 32bit kernels with a 64bit large pmd_t this automatically takes 623 * care of reading the pmd atomically to avoid SMP race conditions 624 * against pmd_populate() when the mmap_sem is hold for reading by the 625 * caller (a special atomic read not done by "gcc" as in the generic 626 * version above, is also needed when THP is disabled because the page 627 * fault can populate the pmd from under us). 628 */ 629static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd) 630{ 631 pmd_t pmdval = pmd_read_atomic(pmd); 632 /* 633 * The barrier will stabilize the pmdval in a register or on 634 * the stack so that it will stop changing under the code. 635 * 636 * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE, 637 * pmd_read_atomic is allowed to return a not atomic pmdval 638 * (for example pointing to an hugepage that has never been 639 * mapped in the pmd). The below checks will only care about 640 * the low part of the pmd with 32bit PAE x86 anyway, with the 641 * exception of pmd_none(). So the important thing is that if 642 * the low part of the pmd is found null, the high part will 643 * be also null or the pmd_none() check below would be 644 * confused. 645 */ 646#ifdef CONFIG_TRANSPARENT_HUGEPAGE 647 barrier(); 648#endif 649 if (pmd_none(pmdval) || pmd_trans_huge(pmdval)) 650 return 1; 651 if (unlikely(pmd_bad(pmdval))) { 652 pmd_clear_bad(pmd); 653 return 1; 654 } 655 return 0; 656} 657 658/* 659 * This is a noop if Transparent Hugepage Support is not built into 660 * the kernel. Otherwise it is equivalent to 661 * pmd_none_or_trans_huge_or_clear_bad(), and shall only be called in 662 * places that already verified the pmd is not none and they want to 663 * walk ptes while holding the mmap sem in read mode (write mode don't 664 * need this). If THP is not enabled, the pmd can't go away under the 665 * code even if MADV_DONTNEED runs, but if THP is enabled we need to 666 * run a pmd_trans_unstable before walking the ptes after 667 * split_huge_page_pmd returns (because it may have run when the pmd 668 * become null, but then a page fault can map in a THP and not a 669 * regular page). 670 */ 671static inline int pmd_trans_unstable(pmd_t *pmd) 672{ 673#ifdef CONFIG_TRANSPARENT_HUGEPAGE 674 return pmd_none_or_trans_huge_or_clear_bad(pmd); 675#else 676 return 0; 677#endif 678} 679 680#ifdef CONFIG_NUMA_BALANCING 681/* 682 * _PAGE_NUMA distinguishes between an unmapped page table entry, an entry that 683 * is protected for PROT_NONE and a NUMA hinting fault entry. If the 684 * architecture defines __PAGE_PROTNONE then it should take that into account 685 * but those that do not can rely on the fact that the NUMA hinting scanner 686 * skips inaccessible VMAs. 687 * 688 * pte/pmd_present() returns true if pte/pmd_numa returns true. Page 689 * fault triggers on those regions if pte/pmd_numa returns true 690 * (because _PAGE_PRESENT is not set). 691 */ 692#ifndef pte_numa 693static inline int pte_numa(pte_t pte) 694{ 695 return ptenuma_flags(pte) == _PAGE_NUMA; 696} 697#endif 698 699#ifndef pmd_numa 700static inline int pmd_numa(pmd_t pmd) 701{ 702 return pmdnuma_flags(pmd) == _PAGE_NUMA; 703} 704#endif 705 706/* 707 * pte/pmd_mknuma sets the _PAGE_ACCESSED bitflag automatically 708 * because they're called by the NUMA hinting minor page fault. If we 709 * wouldn't set the _PAGE_ACCESSED bitflag here, the TLB miss handler 710 * would be forced to set it later while filling the TLB after we 711 * return to userland. That would trigger a second write to memory 712 * that we optimize away by setting _PAGE_ACCESSED here. 713 */ 714#ifndef pte_mknonnuma 715static inline pte_t pte_mknonnuma(pte_t pte) 716{ 717 pteval_t val = pte_val(pte); 718 719 val &= ~_PAGE_NUMA; 720 val |= (_PAGE_PRESENT|_PAGE_ACCESSED); 721 return __pte(val); 722} 723#endif 724 725#ifndef pmd_mknonnuma 726static inline pmd_t pmd_mknonnuma(pmd_t pmd) 727{ 728 pmdval_t val = pmd_val(pmd); 729 730 val &= ~_PAGE_NUMA; 731 val |= (_PAGE_PRESENT|_PAGE_ACCESSED); 732 733 return __pmd(val); 734} 735#endif 736 737#ifndef pte_mknuma 738static inline pte_t pte_mknuma(pte_t pte) 739{ 740 pteval_t val = pte_val(pte); 741 742 VM_BUG_ON(!(val & _PAGE_PRESENT)); 743 744 val &= ~_PAGE_PRESENT; 745 val |= _PAGE_NUMA; 746 747 return __pte(val); 748} 749#endif 750 751#ifndef ptep_set_numa 752static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr, 753 pte_t *ptep) 754{ 755 pte_t ptent = *ptep; 756 757 ptent = pte_mknuma(ptent); 758 set_pte_at(mm, addr, ptep, ptent); 759 return; 760} 761#endif 762 763#ifndef pmd_mknuma 764static inline pmd_t pmd_mknuma(pmd_t pmd) 765{ 766 pmdval_t val = pmd_val(pmd); 767 768 val &= ~_PAGE_PRESENT; 769 val |= _PAGE_NUMA; 770 771 return __pmd(val); 772} 773#endif 774 775#ifndef pmdp_set_numa 776static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr, 777 pmd_t *pmdp) 778{ 779 pmd_t pmd = *pmdp; 780 781 pmd = pmd_mknuma(pmd); 782 set_pmd_at(mm, addr, pmdp, pmd); 783 return; 784} 785#endif 786#else 787static inline int pmd_numa(pmd_t pmd) 788{ 789 return 0; 790} 791 792static inline int pte_numa(pte_t pte) 793{ 794 return 0; 795} 796 797static inline pte_t pte_mknonnuma(pte_t pte) 798{ 799 return pte; 800} 801 802static inline pmd_t pmd_mknonnuma(pmd_t pmd) 803{ 804 return pmd; 805} 806 807static inline pte_t pte_mknuma(pte_t pte) 808{ 809 return pte; 810} 811 812static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr, 813 pte_t *ptep) 814{ 815 return; 816} 817 818 819static inline pmd_t pmd_mknuma(pmd_t pmd) 820{ 821 return pmd; 822} 823 824static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr, 825 pmd_t *pmdp) 826{ 827 return ; 828} 829#endif /* CONFIG_NUMA_BALANCING */ 830 831#endif /* CONFIG_MMU */ 832 833#endif /* !__ASSEMBLY__ */ 834 835#ifndef io_remap_pfn_range 836#define io_remap_pfn_range remap_pfn_range 837#endif 838 839#endif /* _ASM_GENERIC_PGTABLE_H */