xref: /linux/arch/arm64/include/asm/pgtable.h (revision 881f1bb5e25c8982ed963b2d319fc0fc732e55db)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 ARM Ltd.
4  */
5 #ifndef __ASM_PGTABLE_H
6 #define __ASM_PGTABLE_H
7 
8 #include <asm/bug.h>
9 #include <asm/proc-fns.h>
10 
11 #include <asm/memory.h>
12 #include <asm/mte.h>
13 #include <asm/pgtable-hwdef.h>
14 #include <asm/pgtable-prot.h>
15 #include <asm/tlbflush.h>
16 
17 /*
18  * VMALLOC range.
19  *
20  * VMALLOC_START: beginning of the kernel vmalloc space
21  * VMALLOC_END: extends to the available space below vmemmap
22  */
23 #define VMALLOC_START		(MODULES_END)
24 #if VA_BITS == VA_BITS_MIN
25 #define VMALLOC_END		(VMEMMAP_START - SZ_8M)
26 #else
27 #define VMEMMAP_UNUSED_NPAGES	((_PAGE_OFFSET(vabits_actual) - PAGE_OFFSET) >> PAGE_SHIFT)
28 #define VMALLOC_END		(VMEMMAP_START + VMEMMAP_UNUSED_NPAGES * sizeof(struct page) - SZ_8M)
29 #endif
30 
31 #define vmemmap			((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT))
32 
33 #ifndef __ASSEMBLY__
34 
35 #include <asm/cmpxchg.h>
36 #include <asm/fixmap.h>
37 #include <linux/mmdebug.h>
38 #include <linux/mm_types.h>
39 #include <linux/sched.h>
40 #include <linux/page_table_check.h>
41 
42 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
43 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
44 
45 /* Set stride and tlb_level in flush_*_tlb_range */
46 #define flush_pmd_tlb_range(vma, addr, end)	\
47 	__flush_tlb_range(vma, addr, end, PMD_SIZE, false, 2)
48 #define flush_pud_tlb_range(vma, addr, end)	\
49 	__flush_tlb_range(vma, addr, end, PUD_SIZE, false, 1)
50 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
51 
52 /*
53  * Outside of a few very special situations (e.g. hibernation), we always
54  * use broadcast TLB invalidation instructions, therefore a spurious page
55  * fault on one CPU which has been handled concurrently by another CPU
56  * does not need to perform additional invalidation.
57  */
58 #define flush_tlb_fix_spurious_fault(vma, address, ptep) do { } while (0)
59 
60 /*
61  * ZERO_PAGE is a global shared page that is always zero: used
62  * for zero-mapped memory areas etc..
63  */
64 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
65 #define ZERO_PAGE(vaddr)	phys_to_page(__pa_symbol(empty_zero_page))
66 
67 #define pte_ERROR(e)	\
68 	pr_err("%s:%d: bad pte %016llx.\n", __FILE__, __LINE__, pte_val(e))
69 
70 /*
71  * Macros to convert between a physical address and its placement in a
72  * page table entry, taking care of 52-bit addresses.
73  */
74 #ifdef CONFIG_ARM64_PA_BITS_52
75 static inline phys_addr_t __pte_to_phys(pte_t pte)
76 {
77 	pte_val(pte) &= ~PTE_MAYBE_SHARED;
78 	return (pte_val(pte) & PTE_ADDR_LOW) |
79 		((pte_val(pte) & PTE_ADDR_HIGH) << PTE_ADDR_HIGH_SHIFT);
80 }
81 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
82 {
83 	return (phys | (phys >> PTE_ADDR_HIGH_SHIFT)) & PHYS_TO_PTE_ADDR_MASK;
84 }
85 #else
86 #define __pte_to_phys(pte)	(pte_val(pte) & PTE_ADDR_LOW)
87 #define __phys_to_pte_val(phys)	(phys)
88 #endif
89 
90 #define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
91 #define pfn_pte(pfn,prot)	\
92 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
93 
94 #define pte_none(pte)		(!pte_val(pte))
95 #define __pte_clear(mm, addr, ptep) \
96 				__set_pte(ptep, __pte(0))
97 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
98 
99 /*
100  * The following only work if pte_present(). Undefined behaviour otherwise.
101  */
102 #define pte_present(pte)	(!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
103 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
104 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
105 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
106 #define pte_rdonly(pte)		(!!(pte_val(pte) & PTE_RDONLY))
107 #define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
108 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
109 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
110 #define pte_devmap(pte)		(!!(pte_val(pte) & PTE_DEVMAP))
111 #define pte_tagged(pte)		((pte_val(pte) & PTE_ATTRINDX_MASK) == \
112 				 PTE_ATTRINDX(MT_NORMAL_TAGGED))
113 
114 #define pte_cont_addr_end(addr, end)						\
115 ({	unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK;	\
116 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
117 })
118 
119 #define pmd_cont_addr_end(addr, end)						\
120 ({	unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK;	\
121 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
122 })
123 
124 #define pte_hw_dirty(pte)	(pte_write(pte) && !pte_rdonly(pte))
125 #define pte_sw_dirty(pte)	(!!(pte_val(pte) & PTE_DIRTY))
126 #define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))
127 
128 #define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))
129 /*
130  * Execute-only user mappings do not have the PTE_USER bit set. All valid
131  * kernel mappings have the PTE_UXN bit set.
132  */
133 #define pte_valid_not_user(pte) \
134 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
135 /*
136  * Returns true if the pte is valid and has the contiguous bit set.
137  */
138 #define pte_valid_cont(pte)	(pte_valid(pte) && pte_cont(pte))
139 /*
140  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
141  * so that we don't erroneously return false for pages that have been
142  * remapped as PROT_NONE but are yet to be flushed from the TLB.
143  * Note that we can't make any assumptions based on the state of the access
144  * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the
145  * TLB.
146  */
147 #define pte_accessible(mm, pte)	\
148 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
149 
150 /*
151  * p??_access_permitted() is true for valid user mappings (PTE_USER
152  * bit set, subject to the write permission check). For execute-only
153  * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
154  * not set) must return false. PROT_NONE mappings do not have the
155  * PTE_VALID bit set.
156  */
157 #define pte_access_permitted(pte, write) \
158 	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
159 #define pmd_access_permitted(pmd, write) \
160 	(pte_access_permitted(pmd_pte(pmd), (write)))
161 #define pud_access_permitted(pud, write) \
162 	(pte_access_permitted(pud_pte(pud), (write)))
163 
164 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
165 {
166 	pte_val(pte) &= ~pgprot_val(prot);
167 	return pte;
168 }
169 
170 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
171 {
172 	pte_val(pte) |= pgprot_val(prot);
173 	return pte;
174 }
175 
176 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
177 {
178 	pmd_val(pmd) &= ~pgprot_val(prot);
179 	return pmd;
180 }
181 
182 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
183 {
184 	pmd_val(pmd) |= pgprot_val(prot);
185 	return pmd;
186 }
187 
188 static inline pte_t pte_mkwrite_novma(pte_t pte)
189 {
190 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
191 	pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
192 	return pte;
193 }
194 
195 static inline pte_t pte_mkclean(pte_t pte)
196 {
197 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
198 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
199 
200 	return pte;
201 }
202 
203 static inline pte_t pte_mkdirty(pte_t pte)
204 {
205 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
206 
207 	if (pte_write(pte))
208 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
209 
210 	return pte;
211 }
212 
213 static inline pte_t pte_wrprotect(pte_t pte)
214 {
215 	/*
216 	 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
217 	 * clear), set the PTE_DIRTY bit.
218 	 */
219 	if (pte_hw_dirty(pte))
220 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
221 
222 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
223 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
224 	return pte;
225 }
226 
227 static inline pte_t pte_mkold(pte_t pte)
228 {
229 	return clear_pte_bit(pte, __pgprot(PTE_AF));
230 }
231 
232 static inline pte_t pte_mkyoung(pte_t pte)
233 {
234 	return set_pte_bit(pte, __pgprot(PTE_AF));
235 }
236 
237 static inline pte_t pte_mkspecial(pte_t pte)
238 {
239 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
240 }
241 
242 static inline pte_t pte_mkcont(pte_t pte)
243 {
244 	pte = set_pte_bit(pte, __pgprot(PTE_CONT));
245 	return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
246 }
247 
248 static inline pte_t pte_mknoncont(pte_t pte)
249 {
250 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
251 }
252 
253 static inline pte_t pte_mkpresent(pte_t pte)
254 {
255 	return set_pte_bit(pte, __pgprot(PTE_VALID));
256 }
257 
258 static inline pmd_t pmd_mkcont(pmd_t pmd)
259 {
260 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
261 }
262 
263 static inline pte_t pte_mkdevmap(pte_t pte)
264 {
265 	return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL));
266 }
267 
268 static inline void __set_pte(pte_t *ptep, pte_t pte)
269 {
270 	WRITE_ONCE(*ptep, pte);
271 
272 	/*
273 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
274 	 * or update_mmu_cache() have the necessary barriers.
275 	 */
276 	if (pte_valid_not_user(pte)) {
277 		dsb(ishst);
278 		isb();
279 	}
280 }
281 
282 static inline pte_t __ptep_get(pte_t *ptep)
283 {
284 	return READ_ONCE(*ptep);
285 }
286 
287 extern void __sync_icache_dcache(pte_t pteval);
288 bool pgattr_change_is_safe(u64 old, u64 new);
289 
290 /*
291  * PTE bits configuration in the presence of hardware Dirty Bit Management
292  * (PTE_WRITE == PTE_DBM):
293  *
294  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
295  *   0      0      |   1           0          0
296  *   0      1      |   1           1          0
297  *   1      0      |   1           0          1
298  *   1      1      |   0           1          x
299  *
300  * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
301  * the page fault mechanism. Checking the dirty status of a pte becomes:
302  *
303  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
304  */
305 
306 static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep,
307 					   pte_t pte)
308 {
309 	pte_t old_pte;
310 
311 	if (!IS_ENABLED(CONFIG_DEBUG_VM))
312 		return;
313 
314 	old_pte = __ptep_get(ptep);
315 
316 	if (!pte_valid(old_pte) || !pte_valid(pte))
317 		return;
318 	if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
319 		return;
320 
321 	/*
322 	 * Check for potential race with hardware updates of the pte
323 	 * (__ptep_set_access_flags safely changes valid ptes without going
324 	 * through an invalid entry).
325 	 */
326 	VM_WARN_ONCE(!pte_young(pte),
327 		     "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
328 		     __func__, pte_val(old_pte), pte_val(pte));
329 	VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
330 		     "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
331 		     __func__, pte_val(old_pte), pte_val(pte));
332 	VM_WARN_ONCE(!pgattr_change_is_safe(pte_val(old_pte), pte_val(pte)),
333 		     "%s: unsafe attribute change: 0x%016llx -> 0x%016llx",
334 		     __func__, pte_val(old_pte), pte_val(pte));
335 }
336 
337 static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages)
338 {
339 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
340 		__sync_icache_dcache(pte);
341 
342 	/*
343 	 * If the PTE would provide user space access to the tags associated
344 	 * with it then ensure that the MTE tags are synchronised.  Although
345 	 * pte_access_permitted() returns false for exec only mappings, they
346 	 * don't expose tags (instruction fetches don't check tags).
347 	 */
348 	if (system_supports_mte() && pte_access_permitted(pte, false) &&
349 	    !pte_special(pte) && pte_tagged(pte))
350 		mte_sync_tags(pte, nr_pages);
351 }
352 
353 /*
354  * Select all bits except the pfn
355  */
356 static inline pgprot_t pte_pgprot(pte_t pte)
357 {
358 	unsigned long pfn = pte_pfn(pte);
359 
360 	return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
361 }
362 
363 #define pte_advance_pfn pte_advance_pfn
364 static inline pte_t pte_advance_pfn(pte_t pte, unsigned long nr)
365 {
366 	return pfn_pte(pte_pfn(pte) + nr, pte_pgprot(pte));
367 }
368 
369 static inline void __set_ptes(struct mm_struct *mm,
370 			      unsigned long __always_unused addr,
371 			      pte_t *ptep, pte_t pte, unsigned int nr)
372 {
373 	page_table_check_ptes_set(mm, ptep, pte, nr);
374 	__sync_cache_and_tags(pte, nr);
375 
376 	for (;;) {
377 		__check_safe_pte_update(mm, ptep, pte);
378 		__set_pte(ptep, pte);
379 		if (--nr == 0)
380 			break;
381 		ptep++;
382 		pte = pte_advance_pfn(pte, 1);
383 	}
384 }
385 
386 /*
387  * Huge pte definitions.
388  */
389 #define pte_mkhuge(pte)		(__pte(pte_val(pte) & ~PTE_TABLE_BIT))
390 
391 /*
392  * Hugetlb definitions.
393  */
394 #define HUGE_MAX_HSTATE		4
395 #define HPAGE_SHIFT		PMD_SHIFT
396 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
397 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
398 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
399 
400 static inline pte_t pgd_pte(pgd_t pgd)
401 {
402 	return __pte(pgd_val(pgd));
403 }
404 
405 static inline pte_t p4d_pte(p4d_t p4d)
406 {
407 	return __pte(p4d_val(p4d));
408 }
409 
410 static inline pte_t pud_pte(pud_t pud)
411 {
412 	return __pte(pud_val(pud));
413 }
414 
415 static inline pud_t pte_pud(pte_t pte)
416 {
417 	return __pud(pte_val(pte));
418 }
419 
420 static inline pmd_t pud_pmd(pud_t pud)
421 {
422 	return __pmd(pud_val(pud));
423 }
424 
425 static inline pte_t pmd_pte(pmd_t pmd)
426 {
427 	return __pte(pmd_val(pmd));
428 }
429 
430 static inline pmd_t pte_pmd(pte_t pte)
431 {
432 	return __pmd(pte_val(pte));
433 }
434 
435 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
436 {
437 	return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT);
438 }
439 
440 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
441 {
442 	return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
443 }
444 
445 static inline pte_t pte_swp_mkexclusive(pte_t pte)
446 {
447 	return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
448 }
449 
450 static inline int pte_swp_exclusive(pte_t pte)
451 {
452 	return pte_val(pte) & PTE_SWP_EXCLUSIVE;
453 }
454 
455 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
456 {
457 	return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
458 }
459 
460 #ifdef CONFIG_NUMA_BALANCING
461 /*
462  * See the comment in include/linux/pgtable.h
463  */
464 static inline int pte_protnone(pte_t pte)
465 {
466 	return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE;
467 }
468 
469 static inline int pmd_protnone(pmd_t pmd)
470 {
471 	return pte_protnone(pmd_pte(pmd));
472 }
473 #endif
474 
475 #define pmd_present_invalid(pmd)     (!!(pmd_val(pmd) & PMD_PRESENT_INVALID))
476 
477 static inline int pmd_present(pmd_t pmd)
478 {
479 	return pte_present(pmd_pte(pmd)) || pmd_present_invalid(pmd);
480 }
481 
482 /*
483  * THP definitions.
484  */
485 
486 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
487 static inline int pmd_trans_huge(pmd_t pmd)
488 {
489 	return pmd_val(pmd) && pmd_present(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
490 }
491 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
492 
493 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
494 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
495 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
496 #define pmd_user(pmd)		pte_user(pmd_pte(pmd))
497 #define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
498 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
499 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
500 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
501 #define pmd_mkwrite_novma(pmd)	pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)))
502 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
503 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
504 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
505 
506 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
507 {
508 	pmd = set_pmd_bit(pmd, __pgprot(PMD_PRESENT_INVALID));
509 	pmd = clear_pmd_bit(pmd, __pgprot(PMD_SECT_VALID));
510 
511 	return pmd;
512 }
513 
514 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
515 
516 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
517 
518 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
519 #define pmd_devmap(pmd)		pte_devmap(pmd_pte(pmd))
520 #endif
521 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
522 {
523 	return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP)));
524 }
525 
526 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
527 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
528 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
529 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
530 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
531 
532 #define pud_young(pud)		pte_young(pud_pte(pud))
533 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
534 #define pud_write(pud)		pte_write(pud_pte(pud))
535 
536 #define pud_mkhuge(pud)		(__pud(pud_val(pud) & ~PUD_TABLE_BIT))
537 
538 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
539 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
540 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
541 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
542 
543 static inline void __set_pte_at(struct mm_struct *mm,
544 				unsigned long __always_unused addr,
545 				pte_t *ptep, pte_t pte, unsigned int nr)
546 {
547 	__sync_cache_and_tags(pte, nr);
548 	__check_safe_pte_update(mm, ptep, pte);
549 	__set_pte(ptep, pte);
550 }
551 
552 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
553 			      pmd_t *pmdp, pmd_t pmd)
554 {
555 	page_table_check_pmd_set(mm, pmdp, pmd);
556 	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd),
557 						PMD_SIZE >> PAGE_SHIFT);
558 }
559 
560 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
561 			      pud_t *pudp, pud_t pud)
562 {
563 	page_table_check_pud_set(mm, pudp, pud);
564 	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud),
565 						PUD_SIZE >> PAGE_SHIFT);
566 }
567 
568 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
569 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
570 
571 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
572 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
573 
574 #define __pgprot_modify(prot,mask,bits) \
575 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
576 
577 #define pgprot_nx(prot) \
578 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
579 
580 /*
581  * Mark the prot value as uncacheable and unbufferable.
582  */
583 #define pgprot_noncached(prot) \
584 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
585 #define pgprot_writecombine(prot) \
586 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
587 #define pgprot_device(prot) \
588 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
589 #define pgprot_tagged(prot) \
590 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
591 #define pgprot_mhp	pgprot_tagged
592 /*
593  * DMA allocations for non-coherent devices use what the Arm architecture calls
594  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
595  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
596  * is intended for MMIO and thus forbids speculation, preserves access size,
597  * requires strict alignment and can also force write responses to come from the
598  * endpoint.
599  */
600 #define pgprot_dmacoherent(prot) \
601 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
602 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
603 
604 #define __HAVE_PHYS_MEM_ACCESS_PROT
605 struct file;
606 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
607 				     unsigned long size, pgprot_t vma_prot);
608 
609 #define pmd_none(pmd)		(!pmd_val(pmd))
610 
611 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
612 				 PMD_TYPE_TABLE)
613 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
614 				 PMD_TYPE_SECT)
615 #define pmd_leaf(pmd)		(pmd_present(pmd) && !pmd_table(pmd))
616 #define pmd_bad(pmd)		(!pmd_table(pmd))
617 
618 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
619 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
620 
621 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
622 static inline bool pud_sect(pud_t pud) { return false; }
623 static inline bool pud_table(pud_t pud) { return true; }
624 #else
625 #define pud_sect(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
626 				 PUD_TYPE_SECT)
627 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
628 				 PUD_TYPE_TABLE)
629 #endif
630 
631 extern pgd_t init_pg_dir[];
632 extern pgd_t init_pg_end[];
633 extern pgd_t swapper_pg_dir[];
634 extern pgd_t idmap_pg_dir[];
635 extern pgd_t tramp_pg_dir[];
636 extern pgd_t reserved_pg_dir[];
637 
638 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
639 
640 static inline bool in_swapper_pgdir(void *addr)
641 {
642 	return ((unsigned long)addr & PAGE_MASK) ==
643 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
644 }
645 
646 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
647 {
648 #ifdef __PAGETABLE_PMD_FOLDED
649 	if (in_swapper_pgdir(pmdp)) {
650 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
651 		return;
652 	}
653 #endif /* __PAGETABLE_PMD_FOLDED */
654 
655 	WRITE_ONCE(*pmdp, pmd);
656 
657 	if (pmd_valid(pmd)) {
658 		dsb(ishst);
659 		isb();
660 	}
661 }
662 
663 static inline void pmd_clear(pmd_t *pmdp)
664 {
665 	set_pmd(pmdp, __pmd(0));
666 }
667 
668 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
669 {
670 	return __pmd_to_phys(pmd);
671 }
672 
673 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
674 {
675 	return (unsigned long)__va(pmd_page_paddr(pmd));
676 }
677 
678 /* Find an entry in the third-level page table. */
679 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
680 
681 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
682 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
683 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
684 
685 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
686 
687 /* use ONLY for statically allocated translation tables */
688 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
689 
690 /*
691  * Conversion functions: convert a page and protection to a page entry,
692  * and a page entry and page directory to the page they refer to.
693  */
694 #define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
695 
696 #if CONFIG_PGTABLE_LEVELS > 2
697 
698 #define pmd_ERROR(e)	\
699 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
700 
701 #define pud_none(pud)		(!pud_val(pud))
702 #define pud_bad(pud)		(!pud_table(pud))
703 #define pud_present(pud)	pte_present(pud_pte(pud))
704 #ifndef __PAGETABLE_PMD_FOLDED
705 #define pud_leaf(pud)		(pud_present(pud) && !pud_table(pud))
706 #else
707 #define pud_leaf(pud)		false
708 #endif
709 #define pud_valid(pud)		pte_valid(pud_pte(pud))
710 #define pud_user(pud)		pte_user(pud_pte(pud))
711 #define pud_user_exec(pud)	pte_user_exec(pud_pte(pud))
712 
713 static inline bool pgtable_l4_enabled(void);
714 
715 static inline void set_pud(pud_t *pudp, pud_t pud)
716 {
717 	if (!pgtable_l4_enabled() && in_swapper_pgdir(pudp)) {
718 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
719 		return;
720 	}
721 
722 	WRITE_ONCE(*pudp, pud);
723 
724 	if (pud_valid(pud)) {
725 		dsb(ishst);
726 		isb();
727 	}
728 }
729 
730 static inline void pud_clear(pud_t *pudp)
731 {
732 	set_pud(pudp, __pud(0));
733 }
734 
735 static inline phys_addr_t pud_page_paddr(pud_t pud)
736 {
737 	return __pud_to_phys(pud);
738 }
739 
740 static inline pmd_t *pud_pgtable(pud_t pud)
741 {
742 	return (pmd_t *)__va(pud_page_paddr(pud));
743 }
744 
745 /* Find an entry in the second-level page table. */
746 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
747 
748 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
749 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
750 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
751 
752 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
753 
754 /* use ONLY for statically allocated translation tables */
755 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
756 
757 #else
758 
759 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
760 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
761 
762 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
763 #define pmd_set_fixmap(addr)		NULL
764 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
765 #define pmd_clear_fixmap()
766 
767 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
768 
769 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
770 
771 #if CONFIG_PGTABLE_LEVELS > 3
772 
773 static __always_inline bool pgtable_l4_enabled(void)
774 {
775 	if (CONFIG_PGTABLE_LEVELS > 4 || !IS_ENABLED(CONFIG_ARM64_LPA2))
776 		return true;
777 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
778 		return vabits_actual == VA_BITS;
779 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
780 }
781 
782 static inline bool mm_pud_folded(const struct mm_struct *mm)
783 {
784 	return !pgtable_l4_enabled();
785 }
786 #define mm_pud_folded  mm_pud_folded
787 
788 #define pud_ERROR(e)	\
789 	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
790 
791 #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
792 #define p4d_bad(p4d)		(pgtable_l4_enabled() && !(p4d_val(p4d) & 2))
793 #define p4d_present(p4d)	(!p4d_none(p4d))
794 
795 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
796 {
797 	if (in_swapper_pgdir(p4dp)) {
798 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
799 		return;
800 	}
801 
802 	WRITE_ONCE(*p4dp, p4d);
803 	dsb(ishst);
804 	isb();
805 }
806 
807 static inline void p4d_clear(p4d_t *p4dp)
808 {
809 	if (pgtable_l4_enabled())
810 		set_p4d(p4dp, __p4d(0));
811 }
812 
813 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
814 {
815 	return __p4d_to_phys(p4d);
816 }
817 
818 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
819 
820 static inline pud_t *p4d_to_folded_pud(p4d_t *p4dp, unsigned long addr)
821 {
822 	return (pud_t *)PTR_ALIGN_DOWN(p4dp, PAGE_SIZE) + pud_index(addr);
823 }
824 
825 static inline pud_t *p4d_pgtable(p4d_t p4d)
826 {
827 	return (pud_t *)__va(p4d_page_paddr(p4d));
828 }
829 
830 static inline phys_addr_t pud_offset_phys(p4d_t *p4dp, unsigned long addr)
831 {
832 	BUG_ON(!pgtable_l4_enabled());
833 
834 	return p4d_page_paddr(READ_ONCE(*p4dp)) + pud_index(addr) * sizeof(pud_t);
835 }
836 
837 static inline
838 pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long addr)
839 {
840 	if (!pgtable_l4_enabled())
841 		return p4d_to_folded_pud(p4dp, addr);
842 	return (pud_t *)__va(p4d_page_paddr(p4d)) + pud_index(addr);
843 }
844 #define pud_offset_lockless pud_offset_lockless
845 
846 static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long addr)
847 {
848 	return pud_offset_lockless(p4dp, READ_ONCE(*p4dp), addr);
849 }
850 #define pud_offset	pud_offset
851 
852 static inline pud_t *pud_set_fixmap(unsigned long addr)
853 {
854 	if (!pgtable_l4_enabled())
855 		return NULL;
856 	return (pud_t *)set_fixmap_offset(FIX_PUD, addr);
857 }
858 
859 static inline pud_t *pud_set_fixmap_offset(p4d_t *p4dp, unsigned long addr)
860 {
861 	if (!pgtable_l4_enabled())
862 		return p4d_to_folded_pud(p4dp, addr);
863 	return pud_set_fixmap(pud_offset_phys(p4dp, addr));
864 }
865 
866 static inline void pud_clear_fixmap(void)
867 {
868 	if (pgtable_l4_enabled())
869 		clear_fixmap(FIX_PUD);
870 }
871 
872 /* use ONLY for statically allocated translation tables */
873 static inline pud_t *pud_offset_kimg(p4d_t *p4dp, u64 addr)
874 {
875 	if (!pgtable_l4_enabled())
876 		return p4d_to_folded_pud(p4dp, addr);
877 	return (pud_t *)__phys_to_kimg(pud_offset_phys(p4dp, addr));
878 }
879 
880 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
881 
882 #else
883 
884 static inline bool pgtable_l4_enabled(void) { return false; }
885 
886 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
887 
888 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
889 #define pud_set_fixmap(addr)		NULL
890 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
891 #define pud_clear_fixmap()
892 
893 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
894 
895 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
896 
897 #if CONFIG_PGTABLE_LEVELS > 4
898 
899 static __always_inline bool pgtable_l5_enabled(void)
900 {
901 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
902 		return vabits_actual == VA_BITS;
903 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
904 }
905 
906 static inline bool mm_p4d_folded(const struct mm_struct *mm)
907 {
908 	return !pgtable_l5_enabled();
909 }
910 #define mm_p4d_folded  mm_p4d_folded
911 
912 #define p4d_ERROR(e)	\
913 	pr_err("%s:%d: bad p4d %016llx.\n", __FILE__, __LINE__, p4d_val(e))
914 
915 #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
916 #define pgd_bad(pgd)		(pgtable_l5_enabled() && !(pgd_val(pgd) & 2))
917 #define pgd_present(pgd)	(!pgd_none(pgd))
918 
919 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
920 {
921 	if (in_swapper_pgdir(pgdp)) {
922 		set_swapper_pgd(pgdp, __pgd(pgd_val(pgd)));
923 		return;
924 	}
925 
926 	WRITE_ONCE(*pgdp, pgd);
927 	dsb(ishst);
928 	isb();
929 }
930 
931 static inline void pgd_clear(pgd_t *pgdp)
932 {
933 	if (pgtable_l5_enabled())
934 		set_pgd(pgdp, __pgd(0));
935 }
936 
937 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
938 {
939 	return __pgd_to_phys(pgd);
940 }
941 
942 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
943 
944 static inline p4d_t *pgd_to_folded_p4d(pgd_t *pgdp, unsigned long addr)
945 {
946 	return (p4d_t *)PTR_ALIGN_DOWN(pgdp, PAGE_SIZE) + p4d_index(addr);
947 }
948 
949 static inline phys_addr_t p4d_offset_phys(pgd_t *pgdp, unsigned long addr)
950 {
951 	BUG_ON(!pgtable_l5_enabled());
952 
953 	return pgd_page_paddr(READ_ONCE(*pgdp)) + p4d_index(addr) * sizeof(p4d_t);
954 }
955 
956 static inline
957 p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
958 {
959 	if (!pgtable_l5_enabled())
960 		return pgd_to_folded_p4d(pgdp, addr);
961 	return (p4d_t *)__va(pgd_page_paddr(pgd)) + p4d_index(addr);
962 }
963 #define p4d_offset_lockless p4d_offset_lockless
964 
965 static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long addr)
966 {
967 	return p4d_offset_lockless(pgdp, READ_ONCE(*pgdp), addr);
968 }
969 
970 static inline p4d_t *p4d_set_fixmap(unsigned long addr)
971 {
972 	if (!pgtable_l5_enabled())
973 		return NULL;
974 	return (p4d_t *)set_fixmap_offset(FIX_P4D, addr);
975 }
976 
977 static inline p4d_t *p4d_set_fixmap_offset(pgd_t *pgdp, unsigned long addr)
978 {
979 	if (!pgtable_l5_enabled())
980 		return pgd_to_folded_p4d(pgdp, addr);
981 	return p4d_set_fixmap(p4d_offset_phys(pgdp, addr));
982 }
983 
984 static inline void p4d_clear_fixmap(void)
985 {
986 	if (pgtable_l5_enabled())
987 		clear_fixmap(FIX_P4D);
988 }
989 
990 /* use ONLY for statically allocated translation tables */
991 static inline p4d_t *p4d_offset_kimg(pgd_t *pgdp, u64 addr)
992 {
993 	if (!pgtable_l5_enabled())
994 		return pgd_to_folded_p4d(pgdp, addr);
995 	return (p4d_t *)__phys_to_kimg(p4d_offset_phys(pgdp, addr));
996 }
997 
998 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
999 
1000 #else
1001 
1002 static inline bool pgtable_l5_enabled(void) { return false; }
1003 
1004 /* Match p4d_offset folding in <asm/generic/pgtable-nop4d.h> */
1005 #define p4d_set_fixmap(addr)		NULL
1006 #define p4d_set_fixmap_offset(p4dp, addr)	((p4d_t *)p4dp)
1007 #define p4d_clear_fixmap()
1008 
1009 #define p4d_offset_kimg(dir,addr)	((p4d_t *)dir)
1010 
1011 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
1012 
1013 #define pgd_ERROR(e)	\
1014 	pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
1015 
1016 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
1017 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
1018 
1019 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
1020 {
1021 	/*
1022 	 * Normal and Normal-Tagged are two different memory types and indices
1023 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
1024 	 */
1025 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
1026 			      PTE_PROT_NONE | PTE_VALID | PTE_WRITE | PTE_GP |
1027 			      PTE_ATTRINDX_MASK;
1028 	/* preserve the hardware dirty information */
1029 	if (pte_hw_dirty(pte))
1030 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
1031 
1032 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
1033 	/*
1034 	 * If we end up clearing hw dirtiness for a sw-dirty PTE, set hardware
1035 	 * dirtiness again.
1036 	 */
1037 	if (pte_sw_dirty(pte))
1038 		pte = pte_mkdirty(pte);
1039 	return pte;
1040 }
1041 
1042 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1043 {
1044 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
1045 }
1046 
1047 extern int __ptep_set_access_flags(struct vm_area_struct *vma,
1048 				 unsigned long address, pte_t *ptep,
1049 				 pte_t entry, int dirty);
1050 
1051 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1052 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1053 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1054 					unsigned long address, pmd_t *pmdp,
1055 					pmd_t entry, int dirty)
1056 {
1057 	return __ptep_set_access_flags(vma, address, (pte_t *)pmdp,
1058 							pmd_pte(entry), dirty);
1059 }
1060 
1061 static inline int pud_devmap(pud_t pud)
1062 {
1063 	return 0;
1064 }
1065 
1066 static inline int pgd_devmap(pgd_t pgd)
1067 {
1068 	return 0;
1069 }
1070 #endif
1071 
1072 #ifdef CONFIG_PAGE_TABLE_CHECK
1073 static inline bool pte_user_accessible_page(pte_t pte)
1074 {
1075 	return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte));
1076 }
1077 
1078 static inline bool pmd_user_accessible_page(pmd_t pmd)
1079 {
1080 	return pmd_leaf(pmd) && !pmd_present_invalid(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
1081 }
1082 
1083 static inline bool pud_user_accessible_page(pud_t pud)
1084 {
1085 	return pud_leaf(pud) && (pud_user(pud) || pud_user_exec(pud));
1086 }
1087 #endif
1088 
1089 /*
1090  * Atomic pte/pmd modifications.
1091  */
1092 static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma,
1093 					      unsigned long address,
1094 					      pte_t *ptep)
1095 {
1096 	pte_t old_pte, pte;
1097 
1098 	pte = __ptep_get(ptep);
1099 	do {
1100 		old_pte = pte;
1101 		pte = pte_mkold(pte);
1102 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1103 					       pte_val(old_pte), pte_val(pte));
1104 	} while (pte_val(pte) != pte_val(old_pte));
1105 
1106 	return pte_young(pte);
1107 }
1108 
1109 static inline int __ptep_clear_flush_young(struct vm_area_struct *vma,
1110 					 unsigned long address, pte_t *ptep)
1111 {
1112 	int young = __ptep_test_and_clear_young(vma, address, ptep);
1113 
1114 	if (young) {
1115 		/*
1116 		 * We can elide the trailing DSB here since the worst that can
1117 		 * happen is that a CPU continues to use the young entry in its
1118 		 * TLB and we mistakenly reclaim the associated page. The
1119 		 * window for such an event is bounded by the next
1120 		 * context-switch, which provides a DSB to complete the TLB
1121 		 * invalidation.
1122 		 */
1123 		flush_tlb_page_nosync(vma, address);
1124 	}
1125 
1126 	return young;
1127 }
1128 
1129 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1130 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1131 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
1132 					    unsigned long address,
1133 					    pmd_t *pmdp)
1134 {
1135 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
1136 }
1137 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1138 
1139 static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
1140 				       unsigned long address, pte_t *ptep)
1141 {
1142 	pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
1143 
1144 	page_table_check_pte_clear(mm, pte);
1145 
1146 	return pte;
1147 }
1148 
1149 static inline void __clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1150 				pte_t *ptep, unsigned int nr, int full)
1151 {
1152 	for (;;) {
1153 		__ptep_get_and_clear(mm, addr, ptep);
1154 		if (--nr == 0)
1155 			break;
1156 		ptep++;
1157 		addr += PAGE_SIZE;
1158 	}
1159 }
1160 
1161 static inline pte_t __get_and_clear_full_ptes(struct mm_struct *mm,
1162 				unsigned long addr, pte_t *ptep,
1163 				unsigned int nr, int full)
1164 {
1165 	pte_t pte, tmp_pte;
1166 
1167 	pte = __ptep_get_and_clear(mm, addr, ptep);
1168 	while (--nr) {
1169 		ptep++;
1170 		addr += PAGE_SIZE;
1171 		tmp_pte = __ptep_get_and_clear(mm, addr, ptep);
1172 		if (pte_dirty(tmp_pte))
1173 			pte = pte_mkdirty(pte);
1174 		if (pte_young(tmp_pte))
1175 			pte = pte_mkyoung(pte);
1176 	}
1177 	return pte;
1178 }
1179 
1180 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1181 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1182 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1183 					    unsigned long address, pmd_t *pmdp)
1184 {
1185 	pmd_t pmd = __pmd(xchg_relaxed(&pmd_val(*pmdp), 0));
1186 
1187 	page_table_check_pmd_clear(mm, pmd);
1188 
1189 	return pmd;
1190 }
1191 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1192 
1193 static inline void ___ptep_set_wrprotect(struct mm_struct *mm,
1194 					unsigned long address, pte_t *ptep,
1195 					pte_t pte)
1196 {
1197 	pte_t old_pte;
1198 
1199 	do {
1200 		old_pte = pte;
1201 		pte = pte_wrprotect(pte);
1202 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1203 					       pte_val(old_pte), pte_val(pte));
1204 	} while (pte_val(pte) != pte_val(old_pte));
1205 }
1206 
1207 /*
1208  * __ptep_set_wrprotect - mark read-only while trasferring potential hardware
1209  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
1210  */
1211 static inline void __ptep_set_wrprotect(struct mm_struct *mm,
1212 					unsigned long address, pte_t *ptep)
1213 {
1214 	___ptep_set_wrprotect(mm, address, ptep, __ptep_get(ptep));
1215 }
1216 
1217 static inline void __wrprotect_ptes(struct mm_struct *mm, unsigned long address,
1218 				pte_t *ptep, unsigned int nr)
1219 {
1220 	unsigned int i;
1221 
1222 	for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++)
1223 		__ptep_set_wrprotect(mm, address, ptep);
1224 }
1225 
1226 static inline void __clear_young_dirty_pte(struct vm_area_struct *vma,
1227 					   unsigned long addr, pte_t *ptep,
1228 					   pte_t pte, cydp_t flags)
1229 {
1230 	pte_t old_pte;
1231 
1232 	do {
1233 		old_pte = pte;
1234 
1235 		if (flags & CYDP_CLEAR_YOUNG)
1236 			pte = pte_mkold(pte);
1237 		if (flags & CYDP_CLEAR_DIRTY)
1238 			pte = pte_mkclean(pte);
1239 
1240 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1241 					       pte_val(old_pte), pte_val(pte));
1242 	} while (pte_val(pte) != pte_val(old_pte));
1243 }
1244 
1245 static inline void __clear_young_dirty_ptes(struct vm_area_struct *vma,
1246 					    unsigned long addr, pte_t *ptep,
1247 					    unsigned int nr, cydp_t flags)
1248 {
1249 	pte_t pte;
1250 
1251 	for (;;) {
1252 		pte = __ptep_get(ptep);
1253 
1254 		if (flags == (CYDP_CLEAR_YOUNG | CYDP_CLEAR_DIRTY))
1255 			__set_pte(ptep, pte_mkclean(pte_mkold(pte)));
1256 		else
1257 			__clear_young_dirty_pte(vma, addr, ptep, pte, flags);
1258 
1259 		if (--nr == 0)
1260 			break;
1261 		ptep++;
1262 		addr += PAGE_SIZE;
1263 	}
1264 }
1265 
1266 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1267 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1268 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1269 				      unsigned long address, pmd_t *pmdp)
1270 {
1271 	__ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
1272 }
1273 
1274 #define pmdp_establish pmdp_establish
1275 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1276 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1277 {
1278 	page_table_check_pmd_set(vma->vm_mm, pmdp, pmd);
1279 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
1280 }
1281 #endif
1282 
1283 /*
1284  * Encode and decode a swap entry:
1285  *	bits 0-1:	present (must be zero)
1286  *	bits 2:		remember PG_anon_exclusive
1287  *	bits 3-7:	swap type
1288  *	bits 8-57:	swap offset
1289  *	bit  58:	PTE_PROT_NONE (must be zero)
1290  */
1291 #define __SWP_TYPE_SHIFT	3
1292 #define __SWP_TYPE_BITS		5
1293 #define __SWP_OFFSET_BITS	50
1294 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
1295 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
1296 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
1297 
1298 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
1299 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
1300 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
1301 
1302 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1303 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
1304 
1305 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1306 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
1307 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
1308 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
1309 
1310 /*
1311  * Ensure that there are not more swap files than can be encoded in the kernel
1312  * PTEs.
1313  */
1314 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
1315 
1316 #ifdef CONFIG_ARM64_MTE
1317 
1318 #define __HAVE_ARCH_PREPARE_TO_SWAP
1319 extern int arch_prepare_to_swap(struct folio *folio);
1320 
1321 #define __HAVE_ARCH_SWAP_INVALIDATE
1322 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
1323 {
1324 	if (system_supports_mte())
1325 		mte_invalidate_tags(type, offset);
1326 }
1327 
1328 static inline void arch_swap_invalidate_area(int type)
1329 {
1330 	if (system_supports_mte())
1331 		mte_invalidate_tags_area(type);
1332 }
1333 
1334 #define __HAVE_ARCH_SWAP_RESTORE
1335 extern void arch_swap_restore(swp_entry_t entry, struct folio *folio);
1336 
1337 #endif /* CONFIG_ARM64_MTE */
1338 
1339 /*
1340  * On AArch64, the cache coherency is handled via the __set_ptes() function.
1341  */
1342 static inline void update_mmu_cache_range(struct vm_fault *vmf,
1343 		struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
1344 		unsigned int nr)
1345 {
1346 	/*
1347 	 * We don't do anything here, so there's a very small chance of
1348 	 * us retaking a user fault which we just fixed up. The alternative
1349 	 * is doing a dsb(ishst), but that penalises the fastpath.
1350 	 */
1351 }
1352 
1353 #define update_mmu_cache(vma, addr, ptep) \
1354 	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
1355 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
1356 
1357 #ifdef CONFIG_ARM64_PA_BITS_52
1358 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
1359 #else
1360 #define phys_to_ttbr(addr)	(addr)
1361 #endif
1362 
1363 /*
1364  * On arm64 without hardware Access Flag, copying from user will fail because
1365  * the pte is old and cannot be marked young. So we always end up with zeroed
1366  * page after fork() + CoW for pfn mappings. We don't always have a
1367  * hardware-managed access flag on arm64.
1368  */
1369 #define arch_has_hw_pte_young		cpu_has_hw_af
1370 
1371 /*
1372  * Experimentally, it's cheap to set the access flag in hardware and we
1373  * benefit from prefaulting mappings as 'old' to start with.
1374  */
1375 #define arch_wants_old_prefaulted_pte	cpu_has_hw_af
1376 
1377 static inline bool pud_sect_supported(void)
1378 {
1379 	return PAGE_SIZE == SZ_4K;
1380 }
1381 
1382 
1383 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
1384 #define ptep_modify_prot_start ptep_modify_prot_start
1385 extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
1386 				    unsigned long addr, pte_t *ptep);
1387 
1388 #define ptep_modify_prot_commit ptep_modify_prot_commit
1389 extern void ptep_modify_prot_commit(struct vm_area_struct *vma,
1390 				    unsigned long addr, pte_t *ptep,
1391 				    pte_t old_pte, pte_t new_pte);
1392 
1393 #ifdef CONFIG_ARM64_CONTPTE
1394 
1395 /*
1396  * The contpte APIs are used to transparently manage the contiguous bit in ptes
1397  * where it is possible and makes sense to do so. The PTE_CONT bit is considered
1398  * a private implementation detail of the public ptep API (see below).
1399  */
1400 extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
1401 				pte_t *ptep, pte_t pte);
1402 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
1403 				pte_t *ptep, pte_t pte);
1404 extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
1405 extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
1406 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
1407 				pte_t *ptep, pte_t pte, unsigned int nr);
1408 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1409 				pte_t *ptep, unsigned int nr, int full);
1410 extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
1411 				unsigned long addr, pte_t *ptep,
1412 				unsigned int nr, int full);
1413 extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
1414 				unsigned long addr, pte_t *ptep);
1415 extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
1416 				unsigned long addr, pte_t *ptep);
1417 extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
1418 				pte_t *ptep, unsigned int nr);
1419 extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
1420 				unsigned long addr, pte_t *ptep,
1421 				pte_t entry, int dirty);
1422 extern void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
1423 				unsigned long addr, pte_t *ptep,
1424 				unsigned int nr, cydp_t flags);
1425 
1426 static __always_inline void contpte_try_fold(struct mm_struct *mm,
1427 				unsigned long addr, pte_t *ptep, pte_t pte)
1428 {
1429 	/*
1430 	 * Only bother trying if both the virtual and physical addresses are
1431 	 * aligned and correspond to the last entry in a contig range. The core
1432 	 * code mostly modifies ranges from low to high, so this is the likely
1433 	 * the last modification in the contig range, so a good time to fold.
1434 	 * We can't fold special mappings, because there is no associated folio.
1435 	 */
1436 
1437 	const unsigned long contmask = CONT_PTES - 1;
1438 	bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
1439 
1440 	if (unlikely(valign)) {
1441 		bool palign = (pte_pfn(pte) & contmask) == contmask;
1442 
1443 		if (unlikely(palign &&
1444 		    pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)))
1445 			__contpte_try_fold(mm, addr, ptep, pte);
1446 	}
1447 }
1448 
1449 static __always_inline void contpte_try_unfold(struct mm_struct *mm,
1450 				unsigned long addr, pte_t *ptep, pte_t pte)
1451 {
1452 	if (unlikely(pte_valid_cont(pte)))
1453 		__contpte_try_unfold(mm, addr, ptep, pte);
1454 }
1455 
1456 #define pte_batch_hint pte_batch_hint
1457 static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
1458 {
1459 	if (!pte_valid_cont(pte))
1460 		return 1;
1461 
1462 	return CONT_PTES - (((unsigned long)ptep >> 3) & (CONT_PTES - 1));
1463 }
1464 
1465 /*
1466  * The below functions constitute the public API that arm64 presents to the
1467  * core-mm to manipulate PTE entries within their page tables (or at least this
1468  * is the subset of the API that arm64 needs to implement). These public
1469  * versions will automatically and transparently apply the contiguous bit where
1470  * it makes sense to do so. Therefore any users that are contig-aware (e.g.
1471  * hugetlb, kernel mapper) should NOT use these APIs, but instead use the
1472  * private versions, which are prefixed with double underscore. All of these
1473  * APIs except for ptep_get_lockless() are expected to be called with the PTL
1474  * held. Although the contiguous bit is considered private to the
1475  * implementation, it is deliberately allowed to leak through the getters (e.g.
1476  * ptep_get()), back to core code. This is required so that pte_leaf_size() can
1477  * provide an accurate size for perf_get_pgtable_size(). But this leakage means
1478  * its possible a pte will be passed to a setter with the contiguous bit set, so
1479  * we explicitly clear the contiguous bit in those cases to prevent accidentally
1480  * setting it in the pgtable.
1481  */
1482 
1483 #define ptep_get ptep_get
1484 static inline pte_t ptep_get(pte_t *ptep)
1485 {
1486 	pte_t pte = __ptep_get(ptep);
1487 
1488 	if (likely(!pte_valid_cont(pte)))
1489 		return pte;
1490 
1491 	return contpte_ptep_get(ptep, pte);
1492 }
1493 
1494 #define ptep_get_lockless ptep_get_lockless
1495 static inline pte_t ptep_get_lockless(pte_t *ptep)
1496 {
1497 	pte_t pte = __ptep_get(ptep);
1498 
1499 	if (likely(!pte_valid_cont(pte)))
1500 		return pte;
1501 
1502 	return contpte_ptep_get_lockless(ptep);
1503 }
1504 
1505 static inline void set_pte(pte_t *ptep, pte_t pte)
1506 {
1507 	/*
1508 	 * We don't have the mm or vaddr so cannot unfold contig entries (since
1509 	 * it requires tlb maintenance). set_pte() is not used in core code, so
1510 	 * this should never even be called. Regardless do our best to service
1511 	 * any call and emit a warning if there is any attempt to set a pte on
1512 	 * top of an existing contig range.
1513 	 */
1514 	pte_t orig_pte = __ptep_get(ptep);
1515 
1516 	WARN_ON_ONCE(pte_valid_cont(orig_pte));
1517 	__set_pte(ptep, pte_mknoncont(pte));
1518 }
1519 
1520 #define set_ptes set_ptes
1521 static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
1522 				pte_t *ptep, pte_t pte, unsigned int nr)
1523 {
1524 	pte = pte_mknoncont(pte);
1525 
1526 	if (likely(nr == 1)) {
1527 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1528 		__set_ptes(mm, addr, ptep, pte, 1);
1529 		contpte_try_fold(mm, addr, ptep, pte);
1530 	} else {
1531 		contpte_set_ptes(mm, addr, ptep, pte, nr);
1532 	}
1533 }
1534 
1535 static inline void pte_clear(struct mm_struct *mm,
1536 				unsigned long addr, pte_t *ptep)
1537 {
1538 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1539 	__pte_clear(mm, addr, ptep);
1540 }
1541 
1542 #define clear_full_ptes clear_full_ptes
1543 static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1544 				pte_t *ptep, unsigned int nr, int full)
1545 {
1546 	if (likely(nr == 1)) {
1547 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1548 		__clear_full_ptes(mm, addr, ptep, nr, full);
1549 	} else {
1550 		contpte_clear_full_ptes(mm, addr, ptep, nr, full);
1551 	}
1552 }
1553 
1554 #define get_and_clear_full_ptes get_and_clear_full_ptes
1555 static inline pte_t get_and_clear_full_ptes(struct mm_struct *mm,
1556 				unsigned long addr, pte_t *ptep,
1557 				unsigned int nr, int full)
1558 {
1559 	pte_t pte;
1560 
1561 	if (likely(nr == 1)) {
1562 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1563 		pte = __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1564 	} else {
1565 		pte = contpte_get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1566 	}
1567 
1568 	return pte;
1569 }
1570 
1571 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1572 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
1573 				unsigned long addr, pte_t *ptep)
1574 {
1575 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1576 	return __ptep_get_and_clear(mm, addr, ptep);
1577 }
1578 
1579 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1580 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
1581 				unsigned long addr, pte_t *ptep)
1582 {
1583 	pte_t orig_pte = __ptep_get(ptep);
1584 
1585 	if (likely(!pte_valid_cont(orig_pte)))
1586 		return __ptep_test_and_clear_young(vma, addr, ptep);
1587 
1588 	return contpte_ptep_test_and_clear_young(vma, addr, ptep);
1589 }
1590 
1591 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1592 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
1593 				unsigned long addr, pte_t *ptep)
1594 {
1595 	pte_t orig_pte = __ptep_get(ptep);
1596 
1597 	if (likely(!pte_valid_cont(orig_pte)))
1598 		return __ptep_clear_flush_young(vma, addr, ptep);
1599 
1600 	return contpte_ptep_clear_flush_young(vma, addr, ptep);
1601 }
1602 
1603 #define wrprotect_ptes wrprotect_ptes
1604 static __always_inline void wrprotect_ptes(struct mm_struct *mm,
1605 				unsigned long addr, pte_t *ptep, unsigned int nr)
1606 {
1607 	if (likely(nr == 1)) {
1608 		/*
1609 		 * Optimization: wrprotect_ptes() can only be called for present
1610 		 * ptes so we only need to check contig bit as condition for
1611 		 * unfold, and we can remove the contig bit from the pte we read
1612 		 * to avoid re-reading. This speeds up fork() which is sensitive
1613 		 * for order-0 folios. Equivalent to contpte_try_unfold().
1614 		 */
1615 		pte_t orig_pte = __ptep_get(ptep);
1616 
1617 		if (unlikely(pte_cont(orig_pte))) {
1618 			__contpte_try_unfold(mm, addr, ptep, orig_pte);
1619 			orig_pte = pte_mknoncont(orig_pte);
1620 		}
1621 		___ptep_set_wrprotect(mm, addr, ptep, orig_pte);
1622 	} else {
1623 		contpte_wrprotect_ptes(mm, addr, ptep, nr);
1624 	}
1625 }
1626 
1627 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1628 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1629 				unsigned long addr, pte_t *ptep)
1630 {
1631 	wrprotect_ptes(mm, addr, ptep, 1);
1632 }
1633 
1634 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1635 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
1636 				unsigned long addr, pte_t *ptep,
1637 				pte_t entry, int dirty)
1638 {
1639 	pte_t orig_pte = __ptep_get(ptep);
1640 
1641 	entry = pte_mknoncont(entry);
1642 
1643 	if (likely(!pte_valid_cont(orig_pte)))
1644 		return __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1645 
1646 	return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1647 }
1648 
1649 #define clear_young_dirty_ptes clear_young_dirty_ptes
1650 static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
1651 					  unsigned long addr, pte_t *ptep,
1652 					  unsigned int nr, cydp_t flags)
1653 {
1654 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1655 		__clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1656 	else
1657 		contpte_clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1658 }
1659 
1660 #else /* CONFIG_ARM64_CONTPTE */
1661 
1662 #define ptep_get				__ptep_get
1663 #define set_pte					__set_pte
1664 #define set_ptes				__set_ptes
1665 #define pte_clear				__pte_clear
1666 #define clear_full_ptes				__clear_full_ptes
1667 #define get_and_clear_full_ptes			__get_and_clear_full_ptes
1668 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1669 #define ptep_get_and_clear			__ptep_get_and_clear
1670 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1671 #define ptep_test_and_clear_young		__ptep_test_and_clear_young
1672 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1673 #define ptep_clear_flush_young			__ptep_clear_flush_young
1674 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1675 #define ptep_set_wrprotect			__ptep_set_wrprotect
1676 #define wrprotect_ptes				__wrprotect_ptes
1677 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1678 #define ptep_set_access_flags			__ptep_set_access_flags
1679 #define clear_young_dirty_ptes			__clear_young_dirty_ptes
1680 
1681 #endif /* CONFIG_ARM64_CONTPTE */
1682 
1683 #endif /* !__ASSEMBLY__ */
1684 
1685 #endif /* __ASM_PGTABLE_H */
1686