1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* include/asm-generic/tlb.h
3 *
4 * Generic TLB shootdown code
5 *
6 * Copyright 2001 Red Hat, Inc.
7 * Based on code from mm/memory.c Copyright Linus Torvalds and others.
8 *
9 * Copyright 2011 Red Hat, Inc., Peter Zijlstra
10 */
11 #ifndef _ASM_GENERIC__TLB_H
12 #define _ASM_GENERIC__TLB_H
13
14 #include <linux/mmu_notifier.h>
15 #include <linux/swap.h>
16 #include <linux/hugetlb_inline.h>
17 #include <asm/tlbflush.h>
18 #include <asm/cacheflush.h>
19
20 /*
21 * Blindly accessing user memory from NMI context can be dangerous
22 * if we're in the middle of switching the current user task or switching
23 * the loaded mm.
24 */
25 #ifndef nmi_uaccess_okay
26 # define nmi_uaccess_okay() true
27 #endif
28
29 #ifdef CONFIG_MMU
30
31 /*
32 * Generic MMU-gather implementation.
33 *
34 * The mmu_gather data structure is used by the mm code to implement the
35 * correct and efficient ordering of freeing pages and TLB invalidations.
36 *
37 * This correct ordering is:
38 *
39 * 1) unhook page
40 * 2) TLB invalidate page
41 * 3) free page
42 *
43 * That is, we must never free a page before we have ensured there are no live
44 * translations left to it. Otherwise it might be possible to observe (or
45 * worse, change) the page content after it has been reused.
46 *
47 * The mmu_gather API consists of:
48 *
49 * - tlb_gather_mmu() / tlb_gather_mmu_fullmm() / tlb_finish_mmu()
50 *
51 * start and finish a mmu_gather
52 *
53 * Finish in particular will issue a (final) TLB invalidate and free
54 * all (remaining) queued pages.
55 *
56 * - tlb_start_vma() / tlb_end_vma(); marks the start / end of a VMA
57 *
58 * Defaults to flushing at tlb_end_vma() to reset the range; helps when
59 * there's large holes between the VMAs.
60 *
61 * - tlb_remove_table()
62 *
63 * tlb_remove_table() is the basic primitive to free page-table directories
64 * (__p*_free_tlb()). In it's most primitive form it is an alias for
65 * tlb_remove_page() below, for when page directories are pages and have no
66 * additional constraints.
67 *
68 * See also MMU_GATHER_TABLE_FREE and MMU_GATHER_RCU_TABLE_FREE.
69 *
70 * - tlb_remove_page() / __tlb_remove_page()
71 * - tlb_remove_page_size() / __tlb_remove_page_size()
72 * - __tlb_remove_folio_pages()
73 *
74 * __tlb_remove_page_size() is the basic primitive that queues a page for
75 * freeing. __tlb_remove_page() assumes PAGE_SIZE. Both will return a
76 * boolean indicating if the queue is (now) full and a call to
77 * tlb_flush_mmu() is required.
78 *
79 * tlb_remove_page() and tlb_remove_page_size() imply the call to
80 * tlb_flush_mmu() when required and has no return value.
81 *
82 * __tlb_remove_folio_pages() is similar to __tlb_remove_page(), however,
83 * instead of removing a single page, remove the given number of consecutive
84 * pages that are all part of the same (large) folio: just like calling
85 * __tlb_remove_page() on each page individually.
86 *
87 * - tlb_change_page_size()
88 *
89 * call before __tlb_remove_page*() to set the current page-size; implies a
90 * possible tlb_flush_mmu() call.
91 *
92 * - tlb_flush_mmu() / tlb_flush_mmu_tlbonly()
93 *
94 * tlb_flush_mmu_tlbonly() - does the TLB invalidate (and resets
95 * related state, like the range)
96 *
97 * tlb_flush_mmu() - in addition to the above TLB invalidate, also frees
98 * whatever pages are still batched.
99 *
100 * - mmu_gather::fullmm
101 *
102 * A flag set by tlb_gather_mmu_fullmm() to indicate we're going to free
103 * the entire mm; this allows a number of optimizations.
104 *
105 * - We can ignore tlb_{start,end}_vma(); because we don't
106 * care about ranges. Everything will be shot down.
107 *
108 * - (RISC) architectures that use ASIDs can cycle to a new ASID
109 * and delay the invalidation until ASID space runs out.
110 *
111 * - mmu_gather::need_flush_all
112 *
113 * A flag that can be set by the arch code if it wants to force
114 * flush the entire TLB irrespective of the range. For instance
115 * x86-PAE needs this when changing top-level entries.
116 *
117 * And allows the architecture to provide and implement tlb_flush():
118 *
119 * tlb_flush() may, in addition to the above mentioned mmu_gather fields, make
120 * use of:
121 *
122 * - mmu_gather::start / mmu_gather::end
123 *
124 * which provides the range that needs to be flushed to cover the pages to
125 * be freed.
126 *
127 * - mmu_gather::freed_tables
128 *
129 * set when we freed page table pages
130 *
131 * - tlb_get_unmap_shift() / tlb_get_unmap_size()
132 *
133 * returns the smallest TLB entry size unmapped in this range.
134 *
135 * If an architecture does not provide tlb_flush() a default implementation
136 * based on flush_tlb_range() will be used, unless MMU_GATHER_NO_RANGE is
137 * specified, in which case we'll default to flush_tlb_mm().
138 *
139 * Additionally there are a few opt-in features:
140 *
141 * MMU_GATHER_PAGE_SIZE
142 *
143 * This ensures we call tlb_flush() every time tlb_change_page_size() actually
144 * changes the size and provides mmu_gather::page_size to tlb_flush().
145 *
146 * This might be useful if your architecture has size specific TLB
147 * invalidation instructions.
148 *
149 * MMU_GATHER_TABLE_FREE
150 *
151 * This provides tlb_remove_table(), to be used instead of tlb_remove_page()
152 * for page directores (__p*_free_tlb()).
153 *
154 * Useful if your architecture has non-page page directories.
155 *
156 * When used, an architecture is expected to provide __tlb_remove_table()
157 * which does the actual freeing of these pages.
158 *
159 * MMU_GATHER_RCU_TABLE_FREE
160 *
161 * Like MMU_GATHER_TABLE_FREE, and adds semi-RCU semantics to the free (see
162 * comment below).
163 *
164 * Useful if your architecture doesn't use IPIs for remote TLB invalidates
165 * and therefore doesn't naturally serialize with software page-table walkers.
166 *
167 * MMU_GATHER_NO_FLUSH_CACHE
168 *
169 * Indicates the architecture has flush_cache_range() but it needs *NOT* be called
170 * before unmapping a VMA.
171 *
172 * NOTE: strictly speaking we shouldn't have this knob and instead rely on
173 * flush_cache_range() being a NOP, except Sparc64 seems to be
174 * different here.
175 *
176 * MMU_GATHER_MERGE_VMAS
177 *
178 * Indicates the architecture wants to merge ranges over VMAs; typical when
179 * multiple range invalidates are more expensive than a full invalidate.
180 *
181 * MMU_GATHER_NO_RANGE
182 *
183 * Use this if your architecture lacks an efficient flush_tlb_range(). This
184 * option implies MMU_GATHER_MERGE_VMAS above.
185 *
186 * MMU_GATHER_NO_GATHER
187 *
188 * If the option is set the mmu_gather will not track individual pages for
189 * delayed page free anymore. A platform that enables the option needs to
190 * provide its own implementation of the __tlb_remove_page_size() function to
191 * free pages.
192 *
193 * This is useful if your architecture already flushes TLB entries in the
194 * various ptep_get_and_clear() functions.
195 */
196
197 #ifdef CONFIG_MMU_GATHER_TABLE_FREE
198
199 struct mmu_table_batch {
200 #ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE
201 struct rcu_head rcu;
202 #endif
203 unsigned int nr;
204 void *tables[];
205 };
206
207 #define MAX_TABLE_BATCH \
208 ((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *))
209
210 extern void tlb_remove_table(struct mmu_gather *tlb, void *table);
211
212 #else /* !CONFIG_MMU_GATHER_HAVE_TABLE_FREE */
213
214 /*
215 * Without MMU_GATHER_TABLE_FREE the architecture is assumed to have page based
216 * page directories and we can use the normal page batching to free them.
217 */
218 #define tlb_remove_table(tlb, page) tlb_remove_page((tlb), (page))
219
220 #endif /* CONFIG_MMU_GATHER_TABLE_FREE */
221
222 #ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE
223 /*
224 * This allows an architecture that does not use the linux page-tables for
225 * hardware to skip the TLBI when freeing page tables.
226 */
227 #ifndef tlb_needs_table_invalidate
228 #define tlb_needs_table_invalidate() (true)
229 #endif
230
231 void tlb_remove_table_sync_one(void);
232
233 #else
234
235 #ifdef tlb_needs_table_invalidate
236 #error tlb_needs_table_invalidate() requires MMU_GATHER_RCU_TABLE_FREE
237 #endif
238
239 static inline void tlb_remove_table_sync_one(void) { }
240
241 #endif /* CONFIG_MMU_GATHER_RCU_TABLE_FREE */
242
243
244 #ifndef CONFIG_MMU_GATHER_NO_GATHER
245 /*
246 * If we can't allocate a page to make a big batch of page pointers
247 * to work on, then just handle a few from the on-stack structure.
248 */
249 #define MMU_GATHER_BUNDLE 8
250
251 struct mmu_gather_batch {
252 struct mmu_gather_batch *next;
253 unsigned int nr;
254 unsigned int max;
255 struct encoded_page *encoded_pages[];
256 };
257
258 #define MAX_GATHER_BATCH \
259 ((PAGE_SIZE - sizeof(struct mmu_gather_batch)) / sizeof(void *))
260
261 /*
262 * Limit the maximum number of mmu_gather batches to reduce a risk of soft
263 * lockups for non-preemptible kernels on huge machines when a lot of memory
264 * is zapped during unmapping.
265 * 10K pages freed at once should be safe even without a preemption point.
266 */
267 #define MAX_GATHER_BATCH_COUNT (10000UL/MAX_GATHER_BATCH)
268
269 extern bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page,
270 bool delay_rmap, int page_size);
271 bool __tlb_remove_folio_pages(struct mmu_gather *tlb, struct page *page,
272 unsigned int nr_pages, bool delay_rmap);
273
274 #ifdef CONFIG_SMP
275 /*
276 * This both sets 'delayed_rmap', and returns true. It would be an inline
277 * function, except we define it before the 'struct mmu_gather'.
278 */
279 #define tlb_delay_rmap(tlb) (((tlb)->delayed_rmap = 1), true)
280 extern void tlb_flush_rmaps(struct mmu_gather *tlb, struct vm_area_struct *vma);
281 #endif
282
283 #endif
284
285 /*
286 * We have a no-op version of the rmap removal that doesn't
287 * delay anything. That is used on S390, which flushes remote
288 * TLBs synchronously, and on UP, which doesn't have any
289 * remote TLBs to flush and is not preemptible due to this
290 * all happening under the page table lock.
291 */
292 #ifndef tlb_delay_rmap
293 #define tlb_delay_rmap(tlb) (false)
294 static inline void tlb_flush_rmaps(struct mmu_gather *tlb, struct vm_area_struct *vma) { }
295 #endif
296
297 /*
298 * struct mmu_gather is an opaque type used by the mm code for passing around
299 * any data needed by arch specific code for tlb_remove_page.
300 */
301 struct mmu_gather {
302 struct mm_struct *mm;
303
304 #ifdef CONFIG_MMU_GATHER_TABLE_FREE
305 struct mmu_table_batch *batch;
306 #endif
307
308 unsigned long start;
309 unsigned long end;
310 /*
311 * we are in the middle of an operation to clear
312 * a full mm and can make some optimizations
313 */
314 unsigned int fullmm : 1;
315
316 /*
317 * we have performed an operation which
318 * requires a complete flush of the tlb
319 */
320 unsigned int need_flush_all : 1;
321
322 /*
323 * we have removed page directories
324 */
325 unsigned int freed_tables : 1;
326
327 /*
328 * Do we have pending delayed rmap removals?
329 */
330 unsigned int delayed_rmap : 1;
331
332 /*
333 * at which levels have we cleared entries?
334 */
335 unsigned int cleared_ptes : 1;
336 unsigned int cleared_pmds : 1;
337 unsigned int cleared_puds : 1;
338 unsigned int cleared_p4ds : 1;
339
340 /*
341 * tracks VM_EXEC | VM_HUGETLB in tlb_start_vma
342 */
343 unsigned int vma_exec : 1;
344 unsigned int vma_huge : 1;
345 unsigned int vma_pfn : 1;
346
347 unsigned int batch_count;
348
349 #ifndef CONFIG_MMU_GATHER_NO_GATHER
350 struct mmu_gather_batch *active;
351 struct mmu_gather_batch local;
352 struct page *__pages[MMU_GATHER_BUNDLE];
353
354 #ifdef CONFIG_MMU_GATHER_PAGE_SIZE
355 unsigned int page_size;
356 #endif
357 #endif
358 };
359
360 void tlb_flush_mmu(struct mmu_gather *tlb);
361
362 static inline void __tlb_adjust_range(struct mmu_gather *tlb,
363 unsigned long address,
364 unsigned int range_size)
365 {
366 tlb->start = min(tlb->start, address);
367 tlb->end = max(tlb->end, address + range_size);
368 }
369
370 static inline void __tlb_reset_range(struct mmu_gather *tlb)
371 {
372 if (tlb->fullmm) {
373 tlb->start = tlb->end = ~0;
374 } else {
375 tlb->start = TASK_SIZE;
376 tlb->end = 0;
377 }
378 tlb->freed_tables = 0;
379 tlb->cleared_ptes = 0;
380 tlb->cleared_pmds = 0;
381 tlb->cleared_puds = 0;
382 tlb->cleared_p4ds = 0;
383 /*
384 * Do not reset mmu_gather::vma_* fields here, we do not
385 * call into tlb_start_vma() again to set them if there is an
386 * intermediate flush.
387 */
388 }
389
390 #ifdef CONFIG_MMU_GATHER_NO_RANGE
391
392 #if defined(tlb_flush)
393 #error MMU_GATHER_NO_RANGE relies on default tlb_flush()
394 #endif
395
396 /*
397 * When an architecture does not have efficient means of range flushing TLBs
398 * there is no point in doing intermediate flushes on tlb_end_vma() to keep the
399 * range small. We equally don't have to worry about page granularity or other
400 * things.
401 *
402 * All we need to do is issue a full flush for any !0 range.
403 */
404 static inline void tlb_flush(struct mmu_gather *tlb)
405 {
406 if (tlb->end)
407 flush_tlb_mm(tlb->mm);
408 }
409
410 #else /* CONFIG_MMU_GATHER_NO_RANGE */
411
412 #ifndef tlb_flush
413 /*
414 * When an architecture does not provide its own tlb_flush() implementation
415 * but does have a reasonably efficient flush_vma_range() implementation
416 * use that.
417 */
418 static inline void tlb_flush(struct mmu_gather *tlb)
419 {
420 if (tlb->fullmm || tlb->need_flush_all) {
421 flush_tlb_mm(tlb->mm);
422 } else if (tlb->end) {
423 struct vm_area_struct vma = {
424 .vm_mm = tlb->mm,
425 .vm_flags = (tlb->vma_exec ? VM_EXEC : 0) |
426 (tlb->vma_huge ? VM_HUGETLB : 0),
427 };
428
429 flush_tlb_range(&vma, tlb->start, tlb->end);
430 }
431 }
432 #endif
433
434 #endif /* CONFIG_MMU_GATHER_NO_RANGE */
435
436 static inline void
437 tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma)
438 {
439 /*
440 * flush_tlb_range() implementations that look at VM_HUGETLB (tile,
441 * mips-4k) flush only large pages.
442 *
443 * flush_tlb_range() implementations that flush I-TLB also flush D-TLB
444 * (tile, xtensa, arm), so it's ok to just add VM_EXEC to an existing
445 * range.
446 *
447 * We rely on tlb_end_vma() to issue a flush, such that when we reset
448 * these values the batch is empty.
449 */
450 tlb->vma_huge = is_vm_hugetlb_page(vma);
451 tlb->vma_exec = !!(vma->vm_flags & VM_EXEC);
452 tlb->vma_pfn = !!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP));
453 }
454
455 static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
456 {
457 /*
458 * Anything calling __tlb_adjust_range() also sets at least one of
459 * these bits.
460 */
461 if (!(tlb->freed_tables || tlb->cleared_ptes || tlb->cleared_pmds ||
462 tlb->cleared_puds || tlb->cleared_p4ds))
463 return;
464
465 tlb_flush(tlb);
466 __tlb_reset_range(tlb);
467 }
468
469 static inline void tlb_remove_page_size(struct mmu_gather *tlb,
470 struct page *page, int page_size)
471 {
472 if (__tlb_remove_page_size(tlb, page, false, page_size))
473 tlb_flush_mmu(tlb);
474 }
475
476 static __always_inline bool __tlb_remove_page(struct mmu_gather *tlb,
477 struct page *page, bool delay_rmap)
478 {
479 return __tlb_remove_page_size(tlb, page, delay_rmap, PAGE_SIZE);
480 }
481
482 /* tlb_remove_page
483 * Similar to __tlb_remove_page but will call tlb_flush_mmu() itself when
484 * required.
485 */
486 static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
487 {
488 return tlb_remove_page_size(tlb, page, PAGE_SIZE);
489 }
490
491 static inline void tlb_remove_ptdesc(struct mmu_gather *tlb, void *pt)
492 {
493 tlb_remove_table(tlb, pt);
494 }
495
496 /* Like tlb_remove_ptdesc, but for page-like page directories. */
497 static inline void tlb_remove_page_ptdesc(struct mmu_gather *tlb, struct ptdesc *pt)
498 {
499 tlb_remove_page(tlb, ptdesc_page(pt));
500 }
501
502 static inline void tlb_change_page_size(struct mmu_gather *tlb,
503 unsigned int page_size)
504 {
505 #ifdef CONFIG_MMU_GATHER_PAGE_SIZE
506 if (tlb->page_size && tlb->page_size != page_size) {
507 if (!tlb->fullmm && !tlb->need_flush_all)
508 tlb_flush_mmu(tlb);
509 }
510
511 tlb->page_size = page_size;
512 #endif
513 }
514
515 static inline unsigned long tlb_get_unmap_shift(struct mmu_gather *tlb)
516 {
517 if (tlb->cleared_ptes)
518 return PAGE_SHIFT;
519 if (tlb->cleared_pmds)
520 return PMD_SHIFT;
521 if (tlb->cleared_puds)
522 return PUD_SHIFT;
523 if (tlb->cleared_p4ds)
524 return P4D_SHIFT;
525
526 return PAGE_SHIFT;
527 }
528
529 static inline unsigned long tlb_get_unmap_size(struct mmu_gather *tlb)
530 {
531 return 1UL << tlb_get_unmap_shift(tlb);
532 }
533
534 /*
535 * In the case of tlb vma handling, we can optimise these away in the
536 * case where we're doing a full MM flush. When we're doing a munmap,
537 * the vmas are adjusted to only cover the region to be torn down.
538 */
539 static inline void tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
540 {
541 if (tlb->fullmm)
542 return;
543
544 tlb_update_vma_flags(tlb, vma);
545 #ifndef CONFIG_MMU_GATHER_NO_FLUSH_CACHE
546 flush_cache_range(vma, vma->vm_start, vma->vm_end);
547 #endif
548 }
549
550 static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
551 {
552 if (tlb->fullmm)
553 return;
554
555 /*
556 * VM_PFNMAP is more fragile because the core mm will not track the
557 * page mapcount -- there might not be page-frames for these PFNs after
558 * all. Force flush TLBs for such ranges to avoid munmap() vs
559 * unmap_mapping_range() races.
560 */
561 if (tlb->vma_pfn || !IS_ENABLED(CONFIG_MMU_GATHER_MERGE_VMAS)) {
562 /*
563 * Do a TLB flush and reset the range at VMA boundaries; this avoids
564 * the ranges growing with the unused space between consecutive VMAs.
565 */
566 tlb_flush_mmu_tlbonly(tlb);
567 }
568 }
569
570 /*
571 * tlb_flush_{pte|pmd|pud|p4d}_range() adjust the tlb->start and tlb->end,
572 * and set corresponding cleared_*.
573 */
574 static inline void tlb_flush_pte_range(struct mmu_gather *tlb,
575 unsigned long address, unsigned long size)
576 {
577 __tlb_adjust_range(tlb, address, size);
578 tlb->cleared_ptes = 1;
579 }
580
581 static inline void tlb_flush_pmd_range(struct mmu_gather *tlb,
582 unsigned long address, unsigned long size)
583 {
584 __tlb_adjust_range(tlb, address, size);
585 tlb->cleared_pmds = 1;
586 }
587
588 static inline void tlb_flush_pud_range(struct mmu_gather *tlb,
589 unsigned long address, unsigned long size)
590 {
591 __tlb_adjust_range(tlb, address, size);
592 tlb->cleared_puds = 1;
593 }
594
595 static inline void tlb_flush_p4d_range(struct mmu_gather *tlb,
596 unsigned long address, unsigned long size)
597 {
598 __tlb_adjust_range(tlb, address, size);
599 tlb->cleared_p4ds = 1;
600 }
601
602 #ifndef __tlb_remove_tlb_entry
603 static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long address)
604 {
605 }
606 #endif
607
608 /**
609 * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation.
610 *
611 * Record the fact that pte's were really unmapped by updating the range,
612 * so we can later optimise away the tlb invalidate. This helps when
613 * userspace is unmapping already-unmapped pages, which happens quite a lot.
614 */
615 #define tlb_remove_tlb_entry(tlb, ptep, address) \
616 do { \
617 tlb_flush_pte_range(tlb, address, PAGE_SIZE); \
618 __tlb_remove_tlb_entry(tlb, ptep, address); \
619 } while (0)
620
621 /**
622 * tlb_remove_tlb_entries - remember unmapping of multiple consecutive ptes for
623 * later tlb invalidation.
624 *
625 * Similar to tlb_remove_tlb_entry(), but remember unmapping of multiple
626 * consecutive ptes instead of only a single one.
627 */
628 static inline void tlb_remove_tlb_entries(struct mmu_gather *tlb,
629 pte_t *ptep, unsigned int nr, unsigned long address)
630 {
631 tlb_flush_pte_range(tlb, address, PAGE_SIZE * nr);
632 for (;;) {
633 __tlb_remove_tlb_entry(tlb, ptep, address);
634 if (--nr == 0)
635 break;
636 ptep++;
637 address += PAGE_SIZE;
638 }
639 }
640
641 #define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \
642 do { \
643 unsigned long _sz = huge_page_size(h); \
644 if (_sz >= P4D_SIZE) \
645 tlb_flush_p4d_range(tlb, address, _sz); \
646 else if (_sz >= PUD_SIZE) \
647 tlb_flush_pud_range(tlb, address, _sz); \
648 else if (_sz >= PMD_SIZE) \
649 tlb_flush_pmd_range(tlb, address, _sz); \
650 else \
651 tlb_flush_pte_range(tlb, address, _sz); \
652 __tlb_remove_tlb_entry(tlb, ptep, address); \
653 } while (0)
654
655 /**
656 * tlb_remove_pmd_tlb_entry - remember a pmd mapping for later tlb invalidation
657 * This is a nop so far, because only x86 needs it.
658 */
659 #ifndef __tlb_remove_pmd_tlb_entry
660 #define __tlb_remove_pmd_tlb_entry(tlb, pmdp, address) do {} while (0)
661 #endif
662
663 #define tlb_remove_pmd_tlb_entry(tlb, pmdp, address) \
664 do { \
665 tlb_flush_pmd_range(tlb, address, HPAGE_PMD_SIZE); \
666 __tlb_remove_pmd_tlb_entry(tlb, pmdp, address); \
667 } while (0)
668
669 /**
670 * tlb_remove_pud_tlb_entry - remember a pud mapping for later tlb
671 * invalidation. This is a nop so far, because only x86 needs it.
672 */
673 #ifndef __tlb_remove_pud_tlb_entry
674 #define __tlb_remove_pud_tlb_entry(tlb, pudp, address) do {} while (0)
675 #endif
676
677 #define tlb_remove_pud_tlb_entry(tlb, pudp, address) \
678 do { \
679 tlb_flush_pud_range(tlb, address, HPAGE_PUD_SIZE); \
680 __tlb_remove_pud_tlb_entry(tlb, pudp, address); \
681 } while (0)
682
683 /*
684 * For things like page tables caches (ie caching addresses "inside" the
685 * page tables, like x86 does), for legacy reasons, flushing an
686 * individual page had better flush the page table caches behind it. This
687 * is definitely how x86 works, for example. And if you have an
688 * architected non-legacy page table cache (which I'm not aware of
689 * anybody actually doing), you're going to have some architecturally
690 * explicit flushing for that, likely *separate* from a regular TLB entry
691 * flush, and thus you'd need more than just some range expansion..
692 *
693 * So if we ever find an architecture
694 * that would want something that odd, I think it is up to that
695 * architecture to do its own odd thing, not cause pain for others
696 * http://lkml.kernel.org/r/CA+55aFzBggoXtNXQeng5d_mRoDnaMBE5Y+URs+PHR67nUpMtaw@mail.gmail.com
697 *
698 * For now w.r.t page table cache, mark the range_size as PAGE_SIZE
699 */
700
701 #ifndef pte_free_tlb
702 #define pte_free_tlb(tlb, ptep, address) \
703 do { \
704 tlb_flush_pmd_range(tlb, address, PAGE_SIZE); \
705 tlb->freed_tables = 1; \
706 __pte_free_tlb(tlb, ptep, address); \
707 } while (0)
708 #endif
709
710 #ifndef pmd_free_tlb
711 #define pmd_free_tlb(tlb, pmdp, address) \
712 do { \
713 tlb_flush_pud_range(tlb, address, PAGE_SIZE); \
714 tlb->freed_tables = 1; \
715 __pmd_free_tlb(tlb, pmdp, address); \
716 } while (0)
717 #endif
718
719 #ifndef pud_free_tlb
720 #define pud_free_tlb(tlb, pudp, address) \
721 do { \
722 tlb_flush_p4d_range(tlb, address, PAGE_SIZE); \
723 tlb->freed_tables = 1; \
724 __pud_free_tlb(tlb, pudp, address); \
725 } while (0)
726 #endif
727
728 #ifndef p4d_free_tlb
729 #define p4d_free_tlb(tlb, pudp, address) \
730 do { \
731 __tlb_adjust_range(tlb, address, PAGE_SIZE); \
732 tlb->freed_tables = 1; \
733 __p4d_free_tlb(tlb, pudp, address); \
734 } while (0)
735 #endif
736
737 #ifndef pte_needs_flush
738 static inline bool pte_needs_flush(pte_t oldpte, pte_t newpte)
739 {
740 return true;
741 }
742 #endif
743
744 #ifndef huge_pmd_needs_flush
745 static inline bool huge_pmd_needs_flush(pmd_t oldpmd, pmd_t newpmd)
746 {
747 return true;
748 }
749 #endif
750
751 #endif /* CONFIG_MMU */
752
753 #endif /* _ASM_GENERIC__TLB_H */
754
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