1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef LINUX_MM_INLINE_H
3 #define LINUX_MM_INLINE_H
4 
5 #include <linux/atomic.h>
6 #include <linux/huge_mm.h>
7 #include <linux/swap.h>
8 #include <linux/string.h>
9 #include <linux/userfaultfd_k.h>
10 #include <linux/swapops.h>
11 
12 /**
13  * folio_is_file_lru - Should the folio be on a file LRU or anon LRU?
14  * @folio: The folio to test.
15  *
16  * We would like to get this info without a page flag, but the state
17  * needs to survive until the folio is last deleted from the LRU, which
18  * could be as far down as __page_cache_release.
19  *
20  * Return: An integer (not a boolean!) used to sort a folio onto the
21  * right LRU list and to account folios correctly.
22  * 1 if @folio is a regular filesystem backed page cache folio
23  * or a lazily freed anonymous folio (e.g. via MADV_FREE).
24  * 0 if @folio is a normal anonymous folio, a tmpfs folio or otherwise
25  * ram or swap backed folio.
26  */
folio_is_file_lru(struct folio * folio)27 static inline int folio_is_file_lru(struct folio *folio)
28 {
29 	return !folio_test_swapbacked(folio);
30 }
31 
page_is_file_lru(struct page * page)32 static inline int page_is_file_lru(struct page *page)
33 {
34 	return folio_is_file_lru(page_folio(page));
35 }
36 
__update_lru_size(struct lruvec * lruvec,enum lru_list lru,enum zone_type zid,long nr_pages)37 static __always_inline void __update_lru_size(struct lruvec *lruvec,
38 				enum lru_list lru, enum zone_type zid,
39 				long nr_pages)
40 {
41 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
42 
43 	lockdep_assert_held(&lruvec->lru_lock);
44 	WARN_ON_ONCE(nr_pages != (int)nr_pages);
45 
46 	__mod_lruvec_state(lruvec, NR_LRU_BASE + lru, nr_pages);
47 	__mod_zone_page_state(&pgdat->node_zones[zid],
48 				NR_ZONE_LRU_BASE + lru, nr_pages);
49 }
50 
update_lru_size(struct lruvec * lruvec,enum lru_list lru,enum zone_type zid,long nr_pages)51 static __always_inline void update_lru_size(struct lruvec *lruvec,
52 				enum lru_list lru, enum zone_type zid,
53 				long nr_pages)
54 {
55 	__update_lru_size(lruvec, lru, zid, nr_pages);
56 #ifdef CONFIG_MEMCG
57 	mem_cgroup_update_lru_size(lruvec, lru, zid, nr_pages);
58 #endif
59 }
60 
61 /**
62  * __folio_clear_lru_flags - Clear page lru flags before releasing a page.
63  * @folio: The folio that was on lru and now has a zero reference.
64  */
__folio_clear_lru_flags(struct folio * folio)65 static __always_inline void __folio_clear_lru_flags(struct folio *folio)
66 {
67 	VM_BUG_ON_FOLIO(!folio_test_lru(folio), folio);
68 
69 	__folio_clear_lru(folio);
70 
71 	/* this shouldn't happen, so leave the flags to bad_page() */
72 	if (folio_test_active(folio) && folio_test_unevictable(folio))
73 		return;
74 
75 	__folio_clear_active(folio);
76 	__folio_clear_unevictable(folio);
77 }
78 
79 /**
80  * folio_lru_list - Which LRU list should a folio be on?
81  * @folio: The folio to test.
82  *
83  * Return: The LRU list a folio should be on, as an index
84  * into the array of LRU lists.
85  */
folio_lru_list(struct folio * folio)86 static __always_inline enum lru_list folio_lru_list(struct folio *folio)
87 {
88 	enum lru_list lru;
89 
90 	VM_BUG_ON_FOLIO(folio_test_active(folio) && folio_test_unevictable(folio), folio);
91 
92 	if (folio_test_unevictable(folio))
93 		return LRU_UNEVICTABLE;
94 
95 	lru = folio_is_file_lru(folio) ? LRU_INACTIVE_FILE : LRU_INACTIVE_ANON;
96 	if (folio_test_active(folio))
97 		lru += LRU_ACTIVE;
98 
99 	return lru;
100 }
101 
102 #ifdef CONFIG_LRU_GEN
103 
104 #ifdef CONFIG_LRU_GEN_ENABLED
lru_gen_enabled(void)105 static inline bool lru_gen_enabled(void)
106 {
107 	DECLARE_STATIC_KEY_TRUE(lru_gen_caps[NR_LRU_GEN_CAPS]);
108 
109 	return static_branch_likely(&lru_gen_caps[LRU_GEN_CORE]);
110 }
111 #else
lru_gen_enabled(void)112 static inline bool lru_gen_enabled(void)
113 {
114 	DECLARE_STATIC_KEY_FALSE(lru_gen_caps[NR_LRU_GEN_CAPS]);
115 
116 	return static_branch_unlikely(&lru_gen_caps[LRU_GEN_CORE]);
117 }
118 #endif
119 
lru_gen_in_fault(void)120 static inline bool lru_gen_in_fault(void)
121 {
122 	return current->in_lru_fault;
123 }
124 
lru_gen_from_seq(unsigned long seq)125 static inline int lru_gen_from_seq(unsigned long seq)
126 {
127 	return seq % MAX_NR_GENS;
128 }
129 
lru_hist_from_seq(unsigned long seq)130 static inline int lru_hist_from_seq(unsigned long seq)
131 {
132 	return seq % NR_HIST_GENS;
133 }
134 
lru_tier_from_refs(int refs)135 static inline int lru_tier_from_refs(int refs)
136 {
137 	VM_WARN_ON_ONCE(refs > BIT(LRU_REFS_WIDTH));
138 
139 	/* see the comment in folio_lru_refs() */
140 	return order_base_2(refs + 1);
141 }
142 
folio_lru_refs(struct folio * folio)143 static inline int folio_lru_refs(struct folio *folio)
144 {
145 	unsigned long flags = READ_ONCE(folio->flags);
146 	bool workingset = flags & BIT(PG_workingset);
147 
148 	/*
149 	 * Return the number of accesses beyond PG_referenced, i.e., N-1 if the
150 	 * total number of accesses is N>1, since N=0,1 both map to the first
151 	 * tier. lru_tier_from_refs() will account for this off-by-one. Also see
152 	 * the comment on MAX_NR_TIERS.
153 	 */
154 	return ((flags & LRU_REFS_MASK) >> LRU_REFS_PGOFF) + workingset;
155 }
156 
folio_lru_gen(struct folio * folio)157 static inline int folio_lru_gen(struct folio *folio)
158 {
159 	unsigned long flags = READ_ONCE(folio->flags);
160 
161 	return ((flags & LRU_GEN_MASK) >> LRU_GEN_PGOFF) - 1;
162 }
163 
lru_gen_is_active(struct lruvec * lruvec,int gen)164 static inline bool lru_gen_is_active(struct lruvec *lruvec, int gen)
165 {
166 	unsigned long max_seq = lruvec->lrugen.max_seq;
167 
168 	VM_WARN_ON_ONCE(gen >= MAX_NR_GENS);
169 
170 	/* see the comment on MIN_NR_GENS */
171 	return gen == lru_gen_from_seq(max_seq) || gen == lru_gen_from_seq(max_seq - 1);
172 }
173 
lru_gen_update_size(struct lruvec * lruvec,struct folio * folio,int old_gen,int new_gen)174 static inline void lru_gen_update_size(struct lruvec *lruvec, struct folio *folio,
175 				       int old_gen, int new_gen)
176 {
177 	int type = folio_is_file_lru(folio);
178 	int zone = folio_zonenum(folio);
179 	int delta = folio_nr_pages(folio);
180 	enum lru_list lru = type * LRU_INACTIVE_FILE;
181 	struct lru_gen_struct *lrugen = &lruvec->lrugen;
182 
183 	VM_WARN_ON_ONCE(old_gen != -1 && old_gen >= MAX_NR_GENS);
184 	VM_WARN_ON_ONCE(new_gen != -1 && new_gen >= MAX_NR_GENS);
185 	VM_WARN_ON_ONCE(old_gen == -1 && new_gen == -1);
186 
187 	if (old_gen >= 0)
188 		WRITE_ONCE(lrugen->nr_pages[old_gen][type][zone],
189 			   lrugen->nr_pages[old_gen][type][zone] - delta);
190 	if (new_gen >= 0)
191 		WRITE_ONCE(lrugen->nr_pages[new_gen][type][zone],
192 			   lrugen->nr_pages[new_gen][type][zone] + delta);
193 
194 	/* addition */
195 	if (old_gen < 0) {
196 		if (lru_gen_is_active(lruvec, new_gen))
197 			lru += LRU_ACTIVE;
198 		__update_lru_size(lruvec, lru, zone, delta);
199 		return;
200 	}
201 
202 	/* deletion */
203 	if (new_gen < 0) {
204 		if (lru_gen_is_active(lruvec, old_gen))
205 			lru += LRU_ACTIVE;
206 		__update_lru_size(lruvec, lru, zone, -delta);
207 		return;
208 	}
209 
210 	/* promotion */
211 	if (!lru_gen_is_active(lruvec, old_gen) && lru_gen_is_active(lruvec, new_gen)) {
212 		__update_lru_size(lruvec, lru, zone, -delta);
213 		__update_lru_size(lruvec, lru + LRU_ACTIVE, zone, delta);
214 	}
215 
216 	/* demotion requires isolation, e.g., lru_deactivate_fn() */
217 	VM_WARN_ON_ONCE(lru_gen_is_active(lruvec, old_gen) && !lru_gen_is_active(lruvec, new_gen));
218 }
219 
lru_gen_add_folio(struct lruvec * lruvec,struct folio * folio,bool reclaiming)220 static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming)
221 {
222 	unsigned long seq;
223 	unsigned long flags;
224 	int gen = folio_lru_gen(folio);
225 	int type = folio_is_file_lru(folio);
226 	int zone = folio_zonenum(folio);
227 	struct lru_gen_struct *lrugen = &lruvec->lrugen;
228 
229 	VM_WARN_ON_ONCE_FOLIO(gen != -1, folio);
230 
231 	if (folio_test_unevictable(folio) || !lrugen->enabled)
232 		return false;
233 	/*
234 	 * There are three common cases for this page:
235 	 * 1. If it's hot, e.g., freshly faulted in or previously hot and
236 	 *    migrated, add it to the youngest generation.
237 	 * 2. If it's cold but can't be evicted immediately, i.e., an anon page
238 	 *    not in swapcache or a dirty page pending writeback, add it to the
239 	 *    second oldest generation.
240 	 * 3. Everything else (clean, cold) is added to the oldest generation.
241 	 */
242 	if (folio_test_active(folio))
243 		seq = lrugen->max_seq;
244 	else if ((type == LRU_GEN_ANON && !folio_test_swapcache(folio)) ||
245 		 (folio_test_reclaim(folio) &&
246 		  (folio_test_dirty(folio) || folio_test_writeback(folio))))
247 		seq = lrugen->min_seq[type] + 1;
248 	else
249 		seq = lrugen->min_seq[type];
250 
251 	gen = lru_gen_from_seq(seq);
252 	flags = (gen + 1UL) << LRU_GEN_PGOFF;
253 	/* see the comment on MIN_NR_GENS about PG_active */
254 	set_mask_bits(&folio->flags, LRU_GEN_MASK | BIT(PG_active), flags);
255 
256 	lru_gen_update_size(lruvec, folio, -1, gen);
257 	/* for folio_rotate_reclaimable() */
258 	if (reclaiming)
259 		list_add_tail(&folio->lru, &lrugen->lists[gen][type][zone]);
260 	else
261 		list_add(&folio->lru, &lrugen->lists[gen][type][zone]);
262 
263 	return true;
264 }
265 
lru_gen_del_folio(struct lruvec * lruvec,struct folio * folio,bool reclaiming)266 static inline bool lru_gen_del_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming)
267 {
268 	unsigned long flags;
269 	int gen = folio_lru_gen(folio);
270 
271 	if (gen < 0)
272 		return false;
273 
274 	VM_WARN_ON_ONCE_FOLIO(folio_test_active(folio), folio);
275 	VM_WARN_ON_ONCE_FOLIO(folio_test_unevictable(folio), folio);
276 
277 	/* for folio_migrate_flags() */
278 	flags = !reclaiming && lru_gen_is_active(lruvec, gen) ? BIT(PG_active) : 0;
279 	flags = set_mask_bits(&folio->flags, LRU_GEN_MASK, flags);
280 	gen = ((flags & LRU_GEN_MASK) >> LRU_GEN_PGOFF) - 1;
281 
282 	lru_gen_update_size(lruvec, folio, gen, -1);
283 	list_del(&folio->lru);
284 
285 	return true;
286 }
287 
288 #else /* !CONFIG_LRU_GEN */
289 
lru_gen_enabled(void)290 static inline bool lru_gen_enabled(void)
291 {
292 	return false;
293 }
294 
lru_gen_in_fault(void)295 static inline bool lru_gen_in_fault(void)
296 {
297 	return false;
298 }
299 
lru_gen_add_folio(struct lruvec * lruvec,struct folio * folio,bool reclaiming)300 static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming)
301 {
302 	return false;
303 }
304 
lru_gen_del_folio(struct lruvec * lruvec,struct folio * folio,bool reclaiming)305 static inline bool lru_gen_del_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming)
306 {
307 	return false;
308 }
309 
310 #endif /* CONFIG_LRU_GEN */
311 
312 static __always_inline
lruvec_add_folio(struct lruvec * lruvec,struct folio * folio)313 void lruvec_add_folio(struct lruvec *lruvec, struct folio *folio)
314 {
315 	enum lru_list lru = folio_lru_list(folio);
316 
317 	if (lru_gen_add_folio(lruvec, folio, false))
318 		return;
319 
320 	update_lru_size(lruvec, lru, folio_zonenum(folio),
321 			folio_nr_pages(folio));
322 	if (lru != LRU_UNEVICTABLE)
323 		list_add(&folio->lru, &lruvec->lists[lru]);
324 }
325 
add_page_to_lru_list(struct page * page,struct lruvec * lruvec)326 static __always_inline void add_page_to_lru_list(struct page *page,
327 				struct lruvec *lruvec)
328 {
329 	lruvec_add_folio(lruvec, page_folio(page));
330 }
331 
332 static __always_inline
lruvec_add_folio_tail(struct lruvec * lruvec,struct folio * folio)333 void lruvec_add_folio_tail(struct lruvec *lruvec, struct folio *folio)
334 {
335 	enum lru_list lru = folio_lru_list(folio);
336 
337 	if (lru_gen_add_folio(lruvec, folio, true))
338 		return;
339 
340 	update_lru_size(lruvec, lru, folio_zonenum(folio),
341 			folio_nr_pages(folio));
342 	/* This is not expected to be used on LRU_UNEVICTABLE */
343 	list_add_tail(&folio->lru, &lruvec->lists[lru]);
344 }
345 
346 static __always_inline
lruvec_del_folio(struct lruvec * lruvec,struct folio * folio)347 void lruvec_del_folio(struct lruvec *lruvec, struct folio *folio)
348 {
349 	enum lru_list lru = folio_lru_list(folio);
350 
351 	if (lru_gen_del_folio(lruvec, folio, false))
352 		return;
353 
354 	if (lru != LRU_UNEVICTABLE)
355 		list_del(&folio->lru);
356 	update_lru_size(lruvec, lru, folio_zonenum(folio),
357 			-folio_nr_pages(folio));
358 }
359 
del_page_from_lru_list(struct page * page,struct lruvec * lruvec)360 static __always_inline void del_page_from_lru_list(struct page *page,
361 				struct lruvec *lruvec)
362 {
363 	lruvec_del_folio(lruvec, page_folio(page));
364 }
365 
366 #ifdef CONFIG_ANON_VMA_NAME
367 /*
368  * mmap_lock should be read-locked when calling anon_vma_name(). Caller should
369  * either keep holding the lock while using the returned pointer or it should
370  * raise anon_vma_name refcount before releasing the lock.
371  */
372 extern struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma);
373 extern struct anon_vma_name *anon_vma_name_alloc(const char *name);
374 extern void anon_vma_name_free(struct kref *kref);
375 
376 /* mmap_lock should be read-locked */
anon_vma_name_get(struct anon_vma_name * anon_name)377 static inline void anon_vma_name_get(struct anon_vma_name *anon_name)
378 {
379 	if (anon_name)
380 		kref_get(&anon_name->kref);
381 }
382 
anon_vma_name_put(struct anon_vma_name * anon_name)383 static inline void anon_vma_name_put(struct anon_vma_name *anon_name)
384 {
385 	if (anon_name)
386 		kref_put(&anon_name->kref, anon_vma_name_free);
387 }
388 
389 static inline
anon_vma_name_reuse(struct anon_vma_name * anon_name)390 struct anon_vma_name *anon_vma_name_reuse(struct anon_vma_name *anon_name)
391 {
392 	/* Prevent anon_name refcount saturation early on */
393 	if (kref_read(&anon_name->kref) < REFCOUNT_MAX) {
394 		anon_vma_name_get(anon_name);
395 		return anon_name;
396 
397 	}
398 	return anon_vma_name_alloc(anon_name->name);
399 }
400 
dup_anon_vma_name(struct vm_area_struct * orig_vma,struct vm_area_struct * new_vma)401 static inline void dup_anon_vma_name(struct vm_area_struct *orig_vma,
402 				     struct vm_area_struct *new_vma)
403 {
404 	struct anon_vma_name *anon_name = anon_vma_name(orig_vma);
405 
406 	if (anon_name)
407 		new_vma->anon_name = anon_vma_name_reuse(anon_name);
408 }
409 
free_anon_vma_name(struct vm_area_struct * vma)410 static inline void free_anon_vma_name(struct vm_area_struct *vma)
411 {
412 	/*
413 	 * Not using anon_vma_name because it generates a warning if mmap_lock
414 	 * is not held, which might be the case here.
415 	 */
416 	if (!vma->vm_file)
417 		anon_vma_name_put(vma->anon_name);
418 }
419 
anon_vma_name_eq(struct anon_vma_name * anon_name1,struct anon_vma_name * anon_name2)420 static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1,
421 				    struct anon_vma_name *anon_name2)
422 {
423 	if (anon_name1 == anon_name2)
424 		return true;
425 
426 	return anon_name1 && anon_name2 &&
427 		!strcmp(anon_name1->name, anon_name2->name);
428 }
429 
430 #else /* CONFIG_ANON_VMA_NAME */
anon_vma_name(struct vm_area_struct * vma)431 static inline struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma)
432 {
433 	return NULL;
434 }
435 
anon_vma_name_alloc(const char * name)436 static inline struct anon_vma_name *anon_vma_name_alloc(const char *name)
437 {
438 	return NULL;
439 }
440 
anon_vma_name_get(struct anon_vma_name * anon_name)441 static inline void anon_vma_name_get(struct anon_vma_name *anon_name) {}
anon_vma_name_put(struct anon_vma_name * anon_name)442 static inline void anon_vma_name_put(struct anon_vma_name *anon_name) {}
dup_anon_vma_name(struct vm_area_struct * orig_vma,struct vm_area_struct * new_vma)443 static inline void dup_anon_vma_name(struct vm_area_struct *orig_vma,
444 				     struct vm_area_struct *new_vma) {}
free_anon_vma_name(struct vm_area_struct * vma)445 static inline void free_anon_vma_name(struct vm_area_struct *vma) {}
446 
anon_vma_name_eq(struct anon_vma_name * anon_name1,struct anon_vma_name * anon_name2)447 static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1,
448 				    struct anon_vma_name *anon_name2)
449 {
450 	return true;
451 }
452 
453 #endif  /* CONFIG_ANON_VMA_NAME */
454 
init_tlb_flush_pending(struct mm_struct * mm)455 static inline void init_tlb_flush_pending(struct mm_struct *mm)
456 {
457 	atomic_set(&mm->tlb_flush_pending, 0);
458 }
459 
inc_tlb_flush_pending(struct mm_struct * mm)460 static inline void inc_tlb_flush_pending(struct mm_struct *mm)
461 {
462 	atomic_inc(&mm->tlb_flush_pending);
463 	/*
464 	 * The only time this value is relevant is when there are indeed pages
465 	 * to flush. And we'll only flush pages after changing them, which
466 	 * requires the PTL.
467 	 *
468 	 * So the ordering here is:
469 	 *
470 	 *	atomic_inc(&mm->tlb_flush_pending);
471 	 *	spin_lock(&ptl);
472 	 *	...
473 	 *	set_pte_at();
474 	 *	spin_unlock(&ptl);
475 	 *
476 	 *				spin_lock(&ptl)
477 	 *				mm_tlb_flush_pending();
478 	 *				....
479 	 *				spin_unlock(&ptl);
480 	 *
481 	 *	flush_tlb_range();
482 	 *	atomic_dec(&mm->tlb_flush_pending);
483 	 *
484 	 * Where the increment if constrained by the PTL unlock, it thus
485 	 * ensures that the increment is visible if the PTE modification is
486 	 * visible. After all, if there is no PTE modification, nobody cares
487 	 * about TLB flushes either.
488 	 *
489 	 * This very much relies on users (mm_tlb_flush_pending() and
490 	 * mm_tlb_flush_nested()) only caring about _specific_ PTEs (and
491 	 * therefore specific PTLs), because with SPLIT_PTE_PTLOCKS and RCpc
492 	 * locks (PPC) the unlock of one doesn't order against the lock of
493 	 * another PTL.
494 	 *
495 	 * The decrement is ordered by the flush_tlb_range(), such that
496 	 * mm_tlb_flush_pending() will not return false unless all flushes have
497 	 * completed.
498 	 */
499 }
500 
dec_tlb_flush_pending(struct mm_struct * mm)501 static inline void dec_tlb_flush_pending(struct mm_struct *mm)
502 {
503 	/*
504 	 * See inc_tlb_flush_pending().
505 	 *
506 	 * This cannot be smp_mb__before_atomic() because smp_mb() simply does
507 	 * not order against TLB invalidate completion, which is what we need.
508 	 *
509 	 * Therefore we must rely on tlb_flush_*() to guarantee order.
510 	 */
511 	atomic_dec(&mm->tlb_flush_pending);
512 }
513 
mm_tlb_flush_pending(struct mm_struct * mm)514 static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
515 {
516 	/*
517 	 * Must be called after having acquired the PTL; orders against that
518 	 * PTLs release and therefore ensures that if we observe the modified
519 	 * PTE we must also observe the increment from inc_tlb_flush_pending().
520 	 *
521 	 * That is, it only guarantees to return true if there is a flush
522 	 * pending for _this_ PTL.
523 	 */
524 	return atomic_read(&mm->tlb_flush_pending);
525 }
526 
mm_tlb_flush_nested(struct mm_struct * mm)527 static inline bool mm_tlb_flush_nested(struct mm_struct *mm)
528 {
529 	/*
530 	 * Similar to mm_tlb_flush_pending(), we must have acquired the PTL
531 	 * for which there is a TLB flush pending in order to guarantee
532 	 * we've seen both that PTE modification and the increment.
533 	 *
534 	 * (no requirement on actually still holding the PTL, that is irrelevant)
535 	 */
536 	return atomic_read(&mm->tlb_flush_pending) > 1;
537 }
538 
539 /*
540  * If this pte is wr-protected by uffd-wp in any form, arm the special pte to
541  * replace a none pte.  NOTE!  This should only be called when *pte is already
542  * cleared so we will never accidentally replace something valuable.  Meanwhile
543  * none pte also means we are not demoting the pte so tlb flushed is not needed.
544  * E.g., when pte cleared the caller should have taken care of the tlb flush.
545  *
546  * Must be called with pgtable lock held so that no thread will see the none
547  * pte, and if they see it, they'll fault and serialize at the pgtable lock.
548  *
549  * This function is a no-op if PTE_MARKER_UFFD_WP is not enabled.
550  */
551 static inline void
pte_install_uffd_wp_if_needed(struct vm_area_struct * vma,unsigned long addr,pte_t * pte,pte_t pteval)552 pte_install_uffd_wp_if_needed(struct vm_area_struct *vma, unsigned long addr,
553 			      pte_t *pte, pte_t pteval)
554 {
555 #ifdef CONFIG_PTE_MARKER_UFFD_WP
556 	bool arm_uffd_pte = false;
557 
558 	/* The current status of the pte should be "cleared" before calling */
559 	WARN_ON_ONCE(!pte_none(*pte));
560 
561 	if (vma_is_anonymous(vma) || !userfaultfd_wp(vma))
562 		return;
563 
564 	/* A uffd-wp wr-protected normal pte */
565 	if (unlikely(pte_present(pteval) && pte_uffd_wp(pteval)))
566 		arm_uffd_pte = true;
567 
568 	/*
569 	 * A uffd-wp wr-protected swap pte.  Note: this should even cover an
570 	 * existing pte marker with uffd-wp bit set.
571 	 */
572 	if (unlikely(pte_swp_uffd_wp_any(pteval)))
573 		arm_uffd_pte = true;
574 
575 	if (unlikely(arm_uffd_pte))
576 		set_pte_at(vma->vm_mm, addr, pte,
577 			   make_pte_marker(PTE_MARKER_UFFD_WP));
578 #endif
579 }
580 
581 #endif
582