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1da177e4
LT
1#ifndef _ASM_GENERIC_PGTABLE_H
2#define _ASM_GENERIC_PGTABLE_H
3
673eae82 4#ifndef __ASSEMBLY__
9535239f 5#ifdef CONFIG_MMU
673eae82 6
fbd71844 7#include <linux/mm_types.h>
187f1882 8#include <linux/bug.h>
fbd71844 9
6ee8630e
HD
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
1da177e4 20#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
e2cda322
AA
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);
1da177e4
LT
30#endif
31
32#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
e2cda322
AA
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 */
1da177e4
LT
70#endif
71
72#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
e2cda322
AA
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);
1da177e4
LT
80#endif
81
1da177e4 82#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
e2cda322
AA
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;
2d28a227 100 pmd_clear(pmdp);
e2cda322 101 return pmd;
49b24d6b 102}
e2cda322 103#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1da177e4
LT
104#endif
105
a600388d 106#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
e2cda322
AA
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}
a600388d
ZA
115#endif
116
9888a1ca
ZA
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
e2cda322
AA
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}
a600388d
ZA
130#endif
131
1da177e4 132#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
e2cda322
AA
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);
1da177e4
LT
142#endif
143
144#ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
8c65b4a6 145struct mm_struct;
1da177e4
LT
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
e2cda322
AA
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
73636b1a
CM
171extern void pmdp_splitting_flush(struct vm_area_struct *vma,
172 unsigned long address, pmd_t *pmdp);
e2cda322
AA
173#endif
174
e3ebcf64 175#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
6b0b50b0
AK
176extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
177 pgtable_t pgtable);
e3ebcf64
GS
178#endif
179
180#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW
6b0b50b0 181extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
e3ebcf64
GS
182#endif
183
46dcde73
GS
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
1da177e4 189#ifndef __HAVE_ARCH_PTE_SAME
e2cda322
AA
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
45961722
KW
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
e2cda322
AA
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 */
1da177e4
LT
222#endif
223
1da177e4
LT
224#ifndef __HAVE_ARCH_PGD_OFFSET_GATE
225#define pgd_offset_gate(mm, addr) pgd_offset(mm, addr)
226#endif
227
0b0968a3 228#ifndef __HAVE_ARCH_MOVE_PTE
8b1f3124 229#define move_pte(pte, prot, old_addr, new_addr) (pte)
8b1f3124
NP
230#endif
231
2c3cf556 232#ifndef pte_accessible
20841405 233# define pte_accessible(mm, pte) ((void)(pte), 1)
2c3cf556
RR
234#endif
235
c46a7c81
MG
236#ifndef pte_present_nonuma
237#define pte_present_nonuma(pte) pte_present(pte)
238#endif
239
61c77326
SL
240#ifndef flush_tlb_fix_spurious_fault
241#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)
242#endif
243
0634a632
PM
244#ifndef pgprot_noncached
245#define pgprot_noncached(prot) (prot)
246#endif
247
2520bd31 248#ifndef pgprot_writecombine
249#define pgprot_writecombine pgprot_noncached
250#endif
251
1da177e4 252/*
8f6c99c1
HD
253 * When walking page tables, get the address of the next boundary,
254 * or the end address of the range if that comes earlier. Although no
255 * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
1da177e4
LT
256 */
257
1da177e4
LT
258#define pgd_addr_end(addr, end) \
259({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \
260 (__boundary - 1 < (end) - 1)? __boundary: (end); \
261})
1da177e4
LT
262
263#ifndef pud_addr_end
264#define pud_addr_end(addr, end) \
265({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \
266 (__boundary - 1 < (end) - 1)? __boundary: (end); \
267})
268#endif
269
270#ifndef pmd_addr_end
271#define pmd_addr_end(addr, end) \
272({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \
273 (__boundary - 1 < (end) - 1)? __boundary: (end); \
274})
275#endif
276
1da177e4
LT
277/*
278 * When walking page tables, we usually want to skip any p?d_none entries;
279 * and any p?d_bad entries - reporting the error before resetting to none.
280 * Do the tests inline, but report and clear the bad entry in mm/memory.c.
281 */
282void pgd_clear_bad(pgd_t *);
283void pud_clear_bad(pud_t *);
284void pmd_clear_bad(pmd_t *);
285
286static inline int pgd_none_or_clear_bad(pgd_t *pgd)
287{
288 if (pgd_none(*pgd))
289 return 1;
290 if (unlikely(pgd_bad(*pgd))) {
291 pgd_clear_bad(pgd);
292 return 1;
293 }
294 return 0;
295}
296
297static inline int pud_none_or_clear_bad(pud_t *pud)
298{
299 if (pud_none(*pud))
300 return 1;
301 if (unlikely(pud_bad(*pud))) {
302 pud_clear_bad(pud);
303 return 1;
304 }
305 return 0;
306}
307
308static inline int pmd_none_or_clear_bad(pmd_t *pmd)
309{
310 if (pmd_none(*pmd))
311 return 1;
312 if (unlikely(pmd_bad(*pmd))) {
313 pmd_clear_bad(pmd);
314 return 1;
315 }
316 return 0;
317}
9535239f 318
1ea0704e
JF
319static inline pte_t __ptep_modify_prot_start(struct mm_struct *mm,
320 unsigned long addr,
321 pte_t *ptep)
322{
323 /*
324 * Get the current pte state, but zero it out to make it
325 * non-present, preventing the hardware from asynchronously
326 * updating it.
327 */
328 return ptep_get_and_clear(mm, addr, ptep);
329}
330
331static inline void __ptep_modify_prot_commit(struct mm_struct *mm,
332 unsigned long addr,
333 pte_t *ptep, pte_t pte)
334{
335 /*
336 * The pte is non-present, so there's no hardware state to
337 * preserve.
338 */
339 set_pte_at(mm, addr, ptep, pte);
340}
341
342#ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
343/*
344 * Start a pte protection read-modify-write transaction, which
345 * protects against asynchronous hardware modifications to the pte.
346 * The intention is not to prevent the hardware from making pte
347 * updates, but to prevent any updates it may make from being lost.
348 *
349 * This does not protect against other software modifications of the
350 * pte; the appropriate pte lock must be held over the transation.
351 *
352 * Note that this interface is intended to be batchable, meaning that
353 * ptep_modify_prot_commit may not actually update the pte, but merely
354 * queue the update to be done at some later time. The update must be
355 * actually committed before the pte lock is released, however.
356 */
357static inline pte_t ptep_modify_prot_start(struct mm_struct *mm,
358 unsigned long addr,
359 pte_t *ptep)
360{
361 return __ptep_modify_prot_start(mm, addr, ptep);
362}
363
364/*
365 * Commit an update to a pte, leaving any hardware-controlled bits in
366 * the PTE unmodified.
367 */
368static inline void ptep_modify_prot_commit(struct mm_struct *mm,
369 unsigned long addr,
370 pte_t *ptep, pte_t pte)
371{
372 __ptep_modify_prot_commit(mm, addr, ptep, pte);
373}
374#endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */
fe1a6875 375#endif /* CONFIG_MMU */
1ea0704e 376
9535239f
GU
377/*
378 * A facility to provide lazy MMU batching. This allows PTE updates and
379 * page invalidations to be delayed until a call to leave lazy MMU mode
380 * is issued. Some architectures may benefit from doing this, and it is
381 * beneficial for both shadow and direct mode hypervisors, which may batch
382 * the PTE updates which happen during this window. Note that using this
383 * interface requires that read hazards be removed from the code. A read
384 * hazard could result in the direct mode hypervisor case, since the actual
385 * write to the page tables may not yet have taken place, so reads though
386 * a raw PTE pointer after it has been modified are not guaranteed to be
387 * up to date. This mode can only be entered and left under the protection of
388 * the page table locks for all page tables which may be modified. In the UP
389 * case, this is required so that preemption is disabled, and in the SMP case,
390 * it must synchronize the delayed page table writes properly on other CPUs.
391 */
392#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE
393#define arch_enter_lazy_mmu_mode() do {} while (0)
394#define arch_leave_lazy_mmu_mode() do {} while (0)
395#define arch_flush_lazy_mmu_mode() do {} while (0)
396#endif
397
398/*
7fd7d83d
JF
399 * A facility to provide batching of the reload of page tables and
400 * other process state with the actual context switch code for
401 * paravirtualized guests. By convention, only one of the batched
402 * update (lazy) modes (CPU, MMU) should be active at any given time,
403 * entry should never be nested, and entry and exits should always be
404 * paired. This is for sanity of maintaining and reasoning about the
405 * kernel code. In this case, the exit (end of the context switch) is
406 * in architecture-specific code, and so doesn't need a generic
407 * definition.
9535239f 408 */
7fd7d83d 409#ifndef __HAVE_ARCH_START_CONTEXT_SWITCH
224101ed 410#define arch_start_context_switch(prev) do {} while (0)
9535239f
GU
411#endif
412
0f8975ec
PE
413#ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY
414static inline int pte_soft_dirty(pte_t pte)
415{
416 return 0;
417}
418
419static inline int pmd_soft_dirty(pmd_t pmd)
420{
421 return 0;
422}
423
424static inline pte_t pte_mksoft_dirty(pte_t pte)
425{
426 return pte;
427}
428
429static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
430{
431 return pmd;
432}
179ef71c
CG
433
434static inline pte_t pte_swp_mksoft_dirty(pte_t pte)
435{
436 return pte;
437}
438
439static inline int pte_swp_soft_dirty(pte_t pte)
440{
441 return 0;
442}
443
444static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
445{
446 return pte;
447}
41bb3476
CG
448
449static inline pte_t pte_file_clear_soft_dirty(pte_t pte)
450{
451 return pte;
452}
453
454static inline pte_t pte_file_mksoft_dirty(pte_t pte)
455{
456 return pte;
457}
458
459static inline int pte_file_soft_dirty(pte_t pte)
460{
461 return 0;
462}
0f8975ec
PE
463#endif
464
34801ba9 465#ifndef __HAVE_PFNMAP_TRACKING
466/*
5180da41
SS
467 * Interfaces that can be used by architecture code to keep track of
468 * memory type of pfn mappings specified by the remap_pfn_range,
469 * vm_insert_pfn.
470 */
471
472/*
473 * track_pfn_remap is called when a _new_ pfn mapping is being established
474 * by remap_pfn_range() for physical range indicated by pfn and size.
34801ba9 475 */
5180da41 476static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
b3b9c293
KK
477 unsigned long pfn, unsigned long addr,
478 unsigned long size)
34801ba9 479{
480 return 0;
481}
482
483/*
5180da41
SS
484 * track_pfn_insert is called when a _new_ single pfn is established
485 * by vm_insert_pfn().
486 */
487static inline int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
488 unsigned long pfn)
489{
490 return 0;
491}
492
493/*
494 * track_pfn_copy is called when vma that is covering the pfnmap gets
34801ba9 495 * copied through copy_page_range().
496 */
5180da41 497static inline int track_pfn_copy(struct vm_area_struct *vma)
34801ba9 498{
499 return 0;
500}
501
502/*
34801ba9 503 * untrack_pfn_vma is called while unmapping a pfnmap for a region.
504 * untrack can be called for a specific region indicated by pfn and size or
5180da41 505 * can be for the entire vma (in which case pfn, size are zero).
34801ba9 506 */
5180da41
SS
507static inline void untrack_pfn(struct vm_area_struct *vma,
508 unsigned long pfn, unsigned long size)
34801ba9 509{
510}
511#else
5180da41 512extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
b3b9c293
KK
513 unsigned long pfn, unsigned long addr,
514 unsigned long size);
5180da41
SS
515extern int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
516 unsigned long pfn);
517extern int track_pfn_copy(struct vm_area_struct *vma);
518extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
519 unsigned long size);
34801ba9 520#endif
521
816422ad
KS
522#ifdef __HAVE_COLOR_ZERO_PAGE
523static inline int is_zero_pfn(unsigned long pfn)
524{
525 extern unsigned long zero_pfn;
526 unsigned long offset_from_zero_pfn = pfn - zero_pfn;
527 return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
528}
529
2f91ec8c
KS
530#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr))
531
816422ad
KS
532#else
533static inline int is_zero_pfn(unsigned long pfn)
534{
535 extern unsigned long zero_pfn;
536 return pfn == zero_pfn;
537}
538
539static inline unsigned long my_zero_pfn(unsigned long addr)
540{
541 extern unsigned long zero_pfn;
542 return zero_pfn;
543}
544#endif
545
1a5a9906
AA
546#ifdef CONFIG_MMU
547
5f6e8da7
AA
548#ifndef CONFIG_TRANSPARENT_HUGEPAGE
549static inline int pmd_trans_huge(pmd_t pmd)
550{
551 return 0;
552}
553static inline int pmd_trans_splitting(pmd_t pmd)
554{
555 return 0;
556}
e2cda322
AA
557#ifndef __HAVE_ARCH_PMD_WRITE
558static inline int pmd_write(pmd_t pmd)
559{
560 BUG();
561 return 0;
562}
563#endif /* __HAVE_ARCH_PMD_WRITE */
1a5a9906
AA
564#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
565
26c19178
AA
566#ifndef pmd_read_atomic
567static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
568{
569 /*
570 * Depend on compiler for an atomic pmd read. NOTE: this is
571 * only going to work, if the pmdval_t isn't larger than
572 * an unsigned long.
573 */
574 return *pmdp;
575}
576#endif
577
b3084f4d
AK
578#ifndef pmd_move_must_withdraw
579static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl,
580 spinlock_t *old_pmd_ptl)
581{
582 /*
583 * With split pmd lock we also need to move preallocated
584 * PTE page table if new_pmd is on different PMD page table.
585 */
586 return new_pmd_ptl != old_pmd_ptl;
587}
588#endif
589
1a5a9906
AA
590/*
591 * This function is meant to be used by sites walking pagetables with
592 * the mmap_sem hold in read mode to protect against MADV_DONTNEED and
593 * transhuge page faults. MADV_DONTNEED can convert a transhuge pmd
594 * into a null pmd and the transhuge page fault can convert a null pmd
595 * into an hugepmd or into a regular pmd (if the hugepage allocation
596 * fails). While holding the mmap_sem in read mode the pmd becomes
597 * stable and stops changing under us only if it's not null and not a
598 * transhuge pmd. When those races occurs and this function makes a
599 * difference vs the standard pmd_none_or_clear_bad, the result is
600 * undefined so behaving like if the pmd was none is safe (because it
601 * can return none anyway). The compiler level barrier() is critically
602 * important to compute the two checks atomically on the same pmdval.
26c19178
AA
603 *
604 * For 32bit kernels with a 64bit large pmd_t this automatically takes
605 * care of reading the pmd atomically to avoid SMP race conditions
606 * against pmd_populate() when the mmap_sem is hold for reading by the
607 * caller (a special atomic read not done by "gcc" as in the generic
608 * version above, is also needed when THP is disabled because the page
609 * fault can populate the pmd from under us).
1a5a9906
AA
610 */
611static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd)
612{
26c19178 613 pmd_t pmdval = pmd_read_atomic(pmd);
1a5a9906
AA
614 /*
615 * The barrier will stabilize the pmdval in a register or on
616 * the stack so that it will stop changing under the code.
e4eed03f
AA
617 *
618 * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE,
619 * pmd_read_atomic is allowed to return a not atomic pmdval
620 * (for example pointing to an hugepage that has never been
621 * mapped in the pmd). The below checks will only care about
622 * the low part of the pmd with 32bit PAE x86 anyway, with the
623 * exception of pmd_none(). So the important thing is that if
624 * the low part of the pmd is found null, the high part will
625 * be also null or the pmd_none() check below would be
626 * confused.
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627 */
628#ifdef CONFIG_TRANSPARENT_HUGEPAGE
629 barrier();
630#endif
ee53664b 631 if (pmd_none(pmdval) || pmd_trans_huge(pmdval))
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632 return 1;
633 if (unlikely(pmd_bad(pmdval))) {
ee53664b 634 pmd_clear_bad(pmd);
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635 return 1;
636 }
637 return 0;
638}
639
640/*
641 * This is a noop if Transparent Hugepage Support is not built into
642 * the kernel. Otherwise it is equivalent to
643 * pmd_none_or_trans_huge_or_clear_bad(), and shall only be called in
644 * places that already verified the pmd is not none and they want to
645 * walk ptes while holding the mmap sem in read mode (write mode don't
646 * need this). If THP is not enabled, the pmd can't go away under the
647 * code even if MADV_DONTNEED runs, but if THP is enabled we need to
648 * run a pmd_trans_unstable before walking the ptes after
649 * split_huge_page_pmd returns (because it may have run when the pmd
650 * become null, but then a page fault can map in a THP and not a
651 * regular page).
652 */
653static inline int pmd_trans_unstable(pmd_t *pmd)
654{
655#ifdef CONFIG_TRANSPARENT_HUGEPAGE
656 return pmd_none_or_trans_huge_or_clear_bad(pmd);
657#else
658 return 0;
5f6e8da7 659#endif
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660}
661
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662#ifdef CONFIG_NUMA_BALANCING
663#ifdef CONFIG_ARCH_USES_NUMA_PROT_NONE
664/*
665 * _PAGE_NUMA works identical to _PAGE_PROTNONE (it's actually the
666 * same bit too). It's set only when _PAGE_PRESET is not set and it's
667 * never set if _PAGE_PRESENT is set.
668 *
669 * pte/pmd_present() returns true if pte/pmd_numa returns true. Page
670 * fault triggers on those regions if pte/pmd_numa returns true
671 * (because _PAGE_PRESENT is not set).
672 */
673#ifndef pte_numa
674static inline int pte_numa(pte_t pte)
675{
676 return (pte_flags(pte) &
c46a7c81 677 (_PAGE_NUMA|_PAGE_PROTNONE|_PAGE_PRESENT)) == _PAGE_NUMA;
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678}
679#endif
680
681#ifndef pmd_numa
682static inline int pmd_numa(pmd_t pmd)
683{
684 return (pmd_flags(pmd) &
c46a7c81 685 (_PAGE_NUMA|_PAGE_PROTNONE|_PAGE_PRESENT)) == _PAGE_NUMA;
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686}
687#endif
688
689/*
690 * pte/pmd_mknuma sets the _PAGE_ACCESSED bitflag automatically
691 * because they're called by the NUMA hinting minor page fault. If we
692 * wouldn't set the _PAGE_ACCESSED bitflag here, the TLB miss handler
693 * would be forced to set it later while filling the TLB after we
694 * return to userland. That would trigger a second write to memory
695 * that we optimize away by setting _PAGE_ACCESSED here.
696 */
697#ifndef pte_mknonnuma
698static inline pte_t pte_mknonnuma(pte_t pte)
699{
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700 pteval_t val = pte_val(pte);
701
702 val &= ~_PAGE_NUMA;
703 val |= (_PAGE_PRESENT|_PAGE_ACCESSED);
704 return __pte(val);
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705}
706#endif
707
708#ifndef pmd_mknonnuma
709static inline pmd_t pmd_mknonnuma(pmd_t pmd)
710{
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711 pmdval_t val = pmd_val(pmd);
712
713 val &= ~_PAGE_NUMA;
714 val |= (_PAGE_PRESENT|_PAGE_ACCESSED);
715
716 return __pmd(val);
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717}
718#endif
719
720#ifndef pte_mknuma
721static inline pte_t pte_mknuma(pte_t pte)
722{
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723 pteval_t val = pte_val(pte);
724
725 val &= ~_PAGE_PRESENT;
726 val |= _PAGE_NUMA;
727
728 return __pte(val);
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729}
730#endif
731
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732#ifndef ptep_set_numa
733static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr,
734 pte_t *ptep)
735{
736 pte_t ptent = *ptep;
737
738 ptent = pte_mknuma(ptent);
739 set_pte_at(mm, addr, ptep, ptent);
740 return;
741}
742#endif
743
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744#ifndef pmd_mknuma
745static inline pmd_t pmd_mknuma(pmd_t pmd)
746{
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747 pmdval_t val = pmd_val(pmd);
748
749 val &= ~_PAGE_PRESENT;
750 val |= _PAGE_NUMA;
751
752 return __pmd(val);
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753}
754#endif
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755
756#ifndef pmdp_set_numa
757static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr,
758 pmd_t *pmdp)
759{
760 pmd_t pmd = *pmdp;
761
762 pmd = pmd_mknuma(pmd);
763 set_pmd_at(mm, addr, pmdp, pmd);
764 return;
765}
766#endif
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767#else
768extern int pte_numa(pte_t pte);
769extern int pmd_numa(pmd_t pmd);
770extern pte_t pte_mknonnuma(pte_t pte);
771extern pmd_t pmd_mknonnuma(pmd_t pmd);
772extern pte_t pte_mknuma(pte_t pte);
773extern pmd_t pmd_mknuma(pmd_t pmd);
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774extern void ptep_set_numa(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
775extern void pmdp_set_numa(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp);
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776#endif /* CONFIG_ARCH_USES_NUMA_PROT_NONE */
777#else
778static inline int pmd_numa(pmd_t pmd)
779{
780 return 0;
781}
782
783static inline int pte_numa(pte_t pte)
784{
785 return 0;
786}
787
788static inline pte_t pte_mknonnuma(pte_t pte)
789{
790 return pte;
791}
792
793static inline pmd_t pmd_mknonnuma(pmd_t pmd)
794{
795 return pmd;
796}
797
798static inline pte_t pte_mknuma(pte_t pte)
799{
800 return pte;
801}
802
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803static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr,
804 pte_t *ptep)
805{
806 return;
807}
808
809
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810static inline pmd_t pmd_mknuma(pmd_t pmd)
811{
812 return pmd;
813}
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814
815static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr,
816 pmd_t *pmdp)
817{
818 return ;
819}
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820#endif /* CONFIG_NUMA_BALANCING */
821
1a5a9906 822#endif /* CONFIG_MMU */
5f6e8da7 823
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824#endif /* !__ASSEMBLY__ */
825
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826#ifndef io_remap_pfn_range
827#define io_remap_pfn_range remap_pfn_range
828#endif
829
1da177e4 830#endif /* _ASM_GENERIC_PGTABLE_H */