xref: /linux/arch/arm64/include/asm/pgtable.h (revision da51bbcdbace8f43adf6066934c3926b656376e5)
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 static inline bool arch_thp_swp_supported(void)
53 {
54 	return !system_supports_mte();
55 }
56 #define arch_thp_swp_supported arch_thp_swp_supported
57 
58 /*
59  * Outside of a few very special situations (e.g. hibernation), we always
60  * use broadcast TLB invalidation instructions, therefore a spurious page
61  * fault on one CPU which has been handled concurrently by another CPU
62  * does not need to perform additional invalidation.
63  */
64 #define flush_tlb_fix_spurious_fault(vma, address, ptep) do { } while (0)
65 
66 /*
67  * ZERO_PAGE is a global shared page that is always zero: used
68  * for zero-mapped memory areas etc..
69  */
70 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
71 #define ZERO_PAGE(vaddr)	phys_to_page(__pa_symbol(empty_zero_page))
72 
73 #define pte_ERROR(e)	\
74 	pr_err("%s:%d: bad pte %016llx.\n", __FILE__, __LINE__, pte_val(e))
75 
76 /*
77  * Macros to convert between a physical address and its placement in a
78  * page table entry, taking care of 52-bit addresses.
79  */
80 #ifdef CONFIG_ARM64_PA_BITS_52
81 static inline phys_addr_t __pte_to_phys(pte_t pte)
82 {
83 	pte_val(pte) &= ~PTE_MAYBE_SHARED;
84 	return (pte_val(pte) & PTE_ADDR_LOW) |
85 		((pte_val(pte) & PTE_ADDR_HIGH) << PTE_ADDR_HIGH_SHIFT);
86 }
87 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
88 {
89 	return (phys | (phys >> PTE_ADDR_HIGH_SHIFT)) & PHYS_TO_PTE_ADDR_MASK;
90 }
91 #else
92 #define __pte_to_phys(pte)	(pte_val(pte) & PTE_ADDR_LOW)
93 #define __phys_to_pte_val(phys)	(phys)
94 #endif
95 
96 #define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
97 #define pfn_pte(pfn,prot)	\
98 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
99 
100 #define pte_none(pte)		(!pte_val(pte))
101 #define __pte_clear(mm, addr, ptep) \
102 				__set_pte(ptep, __pte(0))
103 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
104 
105 /*
106  * The following only work if pte_present(). Undefined behaviour otherwise.
107  */
108 #define pte_present(pte)	(!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
109 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
110 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
111 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
112 #define pte_rdonly(pte)		(!!(pte_val(pte) & PTE_RDONLY))
113 #define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
114 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
115 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
116 #define pte_devmap(pte)		(!!(pte_val(pte) & PTE_DEVMAP))
117 #define pte_tagged(pte)		((pte_val(pte) & PTE_ATTRINDX_MASK) == \
118 				 PTE_ATTRINDX(MT_NORMAL_TAGGED))
119 
120 #define pte_cont_addr_end(addr, end)						\
121 ({	unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK;	\
122 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
123 })
124 
125 #define pmd_cont_addr_end(addr, end)						\
126 ({	unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK;	\
127 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
128 })
129 
130 #define pte_hw_dirty(pte)	(pte_write(pte) && !pte_rdonly(pte))
131 #define pte_sw_dirty(pte)	(!!(pte_val(pte) & PTE_DIRTY))
132 #define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))
133 
134 #define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))
135 /*
136  * Execute-only user mappings do not have the PTE_USER bit set. All valid
137  * kernel mappings have the PTE_UXN bit set.
138  */
139 #define pte_valid_not_user(pte) \
140 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
141 /*
142  * Returns true if the pte is valid and has the contiguous bit set.
143  */
144 #define pte_valid_cont(pte)	(pte_valid(pte) && pte_cont(pte))
145 /*
146  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
147  * so that we don't erroneously return false for pages that have been
148  * remapped as PROT_NONE but are yet to be flushed from the TLB.
149  * Note that we can't make any assumptions based on the state of the access
150  * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the
151  * TLB.
152  */
153 #define pte_accessible(mm, pte)	\
154 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
155 
156 /*
157  * p??_access_permitted() is true for valid user mappings (PTE_USER
158  * bit set, subject to the write permission check). For execute-only
159  * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
160  * not set) must return false. PROT_NONE mappings do not have the
161  * PTE_VALID bit set.
162  */
163 #define pte_access_permitted(pte, write) \
164 	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
165 #define pmd_access_permitted(pmd, write) \
166 	(pte_access_permitted(pmd_pte(pmd), (write)))
167 #define pud_access_permitted(pud, write) \
168 	(pte_access_permitted(pud_pte(pud), (write)))
169 
170 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
171 {
172 	pte_val(pte) &= ~pgprot_val(prot);
173 	return pte;
174 }
175 
176 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
177 {
178 	pte_val(pte) |= pgprot_val(prot);
179 	return pte;
180 }
181 
182 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
183 {
184 	pmd_val(pmd) &= ~pgprot_val(prot);
185 	return pmd;
186 }
187 
188 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
189 {
190 	pmd_val(pmd) |= pgprot_val(prot);
191 	return pmd;
192 }
193 
194 static inline pte_t pte_mkwrite_novma(pte_t pte)
195 {
196 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
197 	pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
198 	return pte;
199 }
200 
201 static inline pte_t pte_mkclean(pte_t pte)
202 {
203 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
204 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
205 
206 	return pte;
207 }
208 
209 static inline pte_t pte_mkdirty(pte_t pte)
210 {
211 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
212 
213 	if (pte_write(pte))
214 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
215 
216 	return pte;
217 }
218 
219 static inline pte_t pte_wrprotect(pte_t pte)
220 {
221 	/*
222 	 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
223 	 * clear), set the PTE_DIRTY bit.
224 	 */
225 	if (pte_hw_dirty(pte))
226 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
227 
228 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
229 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
230 	return pte;
231 }
232 
233 static inline pte_t pte_mkold(pte_t pte)
234 {
235 	return clear_pte_bit(pte, __pgprot(PTE_AF));
236 }
237 
238 static inline pte_t pte_mkyoung(pte_t pte)
239 {
240 	return set_pte_bit(pte, __pgprot(PTE_AF));
241 }
242 
243 static inline pte_t pte_mkspecial(pte_t pte)
244 {
245 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
246 }
247 
248 static inline pte_t pte_mkcont(pte_t pte)
249 {
250 	pte = set_pte_bit(pte, __pgprot(PTE_CONT));
251 	return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
252 }
253 
254 static inline pte_t pte_mknoncont(pte_t pte)
255 {
256 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
257 }
258 
259 static inline pte_t pte_mkpresent(pte_t pte)
260 {
261 	return set_pte_bit(pte, __pgprot(PTE_VALID));
262 }
263 
264 static inline pmd_t pmd_mkcont(pmd_t pmd)
265 {
266 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
267 }
268 
269 static inline pte_t pte_mkdevmap(pte_t pte)
270 {
271 	return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL));
272 }
273 
274 static inline void __set_pte(pte_t *ptep, pte_t pte)
275 {
276 	WRITE_ONCE(*ptep, pte);
277 
278 	/*
279 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
280 	 * or update_mmu_cache() have the necessary barriers.
281 	 */
282 	if (pte_valid_not_user(pte)) {
283 		dsb(ishst);
284 		isb();
285 	}
286 }
287 
288 static inline pte_t __ptep_get(pte_t *ptep)
289 {
290 	return READ_ONCE(*ptep);
291 }
292 
293 extern void __sync_icache_dcache(pte_t pteval);
294 bool pgattr_change_is_safe(u64 old, u64 new);
295 
296 /*
297  * PTE bits configuration in the presence of hardware Dirty Bit Management
298  * (PTE_WRITE == PTE_DBM):
299  *
300  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
301  *   0      0      |   1           0          0
302  *   0      1      |   1           1          0
303  *   1      0      |   1           0          1
304  *   1      1      |   0           1          x
305  *
306  * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
307  * the page fault mechanism. Checking the dirty status of a pte becomes:
308  *
309  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
310  */
311 
312 static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep,
313 					   pte_t pte)
314 {
315 	pte_t old_pte;
316 
317 	if (!IS_ENABLED(CONFIG_DEBUG_VM))
318 		return;
319 
320 	old_pte = __ptep_get(ptep);
321 
322 	if (!pte_valid(old_pte) || !pte_valid(pte))
323 		return;
324 	if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
325 		return;
326 
327 	/*
328 	 * Check for potential race with hardware updates of the pte
329 	 * (__ptep_set_access_flags safely changes valid ptes without going
330 	 * through an invalid entry).
331 	 */
332 	VM_WARN_ONCE(!pte_young(pte),
333 		     "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
334 		     __func__, pte_val(old_pte), pte_val(pte));
335 	VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
336 		     "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
337 		     __func__, pte_val(old_pte), pte_val(pte));
338 	VM_WARN_ONCE(!pgattr_change_is_safe(pte_val(old_pte), pte_val(pte)),
339 		     "%s: unsafe attribute change: 0x%016llx -> 0x%016llx",
340 		     __func__, pte_val(old_pte), pte_val(pte));
341 }
342 
343 static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages)
344 {
345 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
346 		__sync_icache_dcache(pte);
347 
348 	/*
349 	 * If the PTE would provide user space access to the tags associated
350 	 * with it then ensure that the MTE tags are synchronised.  Although
351 	 * pte_access_permitted() returns false for exec only mappings, they
352 	 * don't expose tags (instruction fetches don't check tags).
353 	 */
354 	if (system_supports_mte() && pte_access_permitted(pte, false) &&
355 	    !pte_special(pte) && pte_tagged(pte))
356 		mte_sync_tags(pte, nr_pages);
357 }
358 
359 /*
360  * Select all bits except the pfn
361  */
362 static inline pgprot_t pte_pgprot(pte_t pte)
363 {
364 	unsigned long pfn = pte_pfn(pte);
365 
366 	return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
367 }
368 
369 #define pte_advance_pfn pte_advance_pfn
370 static inline pte_t pte_advance_pfn(pte_t pte, unsigned long nr)
371 {
372 	return pfn_pte(pte_pfn(pte) + nr, pte_pgprot(pte));
373 }
374 
375 static inline void __set_ptes(struct mm_struct *mm,
376 			      unsigned long __always_unused addr,
377 			      pte_t *ptep, pte_t pte, unsigned int nr)
378 {
379 	page_table_check_ptes_set(mm, ptep, pte, nr);
380 	__sync_cache_and_tags(pte, nr);
381 
382 	for (;;) {
383 		__check_safe_pte_update(mm, ptep, pte);
384 		__set_pte(ptep, pte);
385 		if (--nr == 0)
386 			break;
387 		ptep++;
388 		pte = pte_advance_pfn(pte, 1);
389 	}
390 }
391 
392 /*
393  * Huge pte definitions.
394  */
395 #define pte_mkhuge(pte)		(__pte(pte_val(pte) & ~PTE_TABLE_BIT))
396 
397 /*
398  * Hugetlb definitions.
399  */
400 #define HUGE_MAX_HSTATE		4
401 #define HPAGE_SHIFT		PMD_SHIFT
402 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
403 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
404 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
405 
406 static inline pte_t pgd_pte(pgd_t pgd)
407 {
408 	return __pte(pgd_val(pgd));
409 }
410 
411 static inline pte_t p4d_pte(p4d_t p4d)
412 {
413 	return __pte(p4d_val(p4d));
414 }
415 
416 static inline pte_t pud_pte(pud_t pud)
417 {
418 	return __pte(pud_val(pud));
419 }
420 
421 static inline pud_t pte_pud(pte_t pte)
422 {
423 	return __pud(pte_val(pte));
424 }
425 
426 static inline pmd_t pud_pmd(pud_t pud)
427 {
428 	return __pmd(pud_val(pud));
429 }
430 
431 static inline pte_t pmd_pte(pmd_t pmd)
432 {
433 	return __pte(pmd_val(pmd));
434 }
435 
436 static inline pmd_t pte_pmd(pte_t pte)
437 {
438 	return __pmd(pte_val(pte));
439 }
440 
441 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
442 {
443 	return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT);
444 }
445 
446 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
447 {
448 	return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
449 }
450 
451 static inline pte_t pte_swp_mkexclusive(pte_t pte)
452 {
453 	return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
454 }
455 
456 static inline int pte_swp_exclusive(pte_t pte)
457 {
458 	return pte_val(pte) & PTE_SWP_EXCLUSIVE;
459 }
460 
461 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
462 {
463 	return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
464 }
465 
466 #ifdef CONFIG_NUMA_BALANCING
467 /*
468  * See the comment in include/linux/pgtable.h
469  */
470 static inline int pte_protnone(pte_t pte)
471 {
472 	return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE;
473 }
474 
475 static inline int pmd_protnone(pmd_t pmd)
476 {
477 	return pte_protnone(pmd_pte(pmd));
478 }
479 #endif
480 
481 #define pmd_present_invalid(pmd)     (!!(pmd_val(pmd) & PMD_PRESENT_INVALID))
482 
483 static inline int pmd_present(pmd_t pmd)
484 {
485 	return pte_present(pmd_pte(pmd)) || pmd_present_invalid(pmd);
486 }
487 
488 /*
489  * THP definitions.
490  */
491 
492 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
493 static inline int pmd_trans_huge(pmd_t pmd)
494 {
495 	return pmd_val(pmd) && pmd_present(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
496 }
497 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
498 
499 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
500 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
501 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
502 #define pmd_user(pmd)		pte_user(pmd_pte(pmd))
503 #define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
504 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
505 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
506 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
507 #define pmd_mkwrite_novma(pmd)	pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)))
508 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
509 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
510 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
511 
512 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
513 {
514 	pmd = set_pmd_bit(pmd, __pgprot(PMD_PRESENT_INVALID));
515 	pmd = clear_pmd_bit(pmd, __pgprot(PMD_SECT_VALID));
516 
517 	return pmd;
518 }
519 
520 #define pmd_thp_or_huge(pmd)	(pmd_huge(pmd) || pmd_trans_huge(pmd))
521 
522 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
523 
524 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
525 
526 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
527 #define pmd_devmap(pmd)		pte_devmap(pmd_pte(pmd))
528 #endif
529 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
530 {
531 	return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP)));
532 }
533 
534 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
535 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
536 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
537 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
538 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
539 
540 #define pud_young(pud)		pte_young(pud_pte(pud))
541 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
542 #define pud_write(pud)		pte_write(pud_pte(pud))
543 
544 #define pud_mkhuge(pud)		(__pud(pud_val(pud) & ~PUD_TABLE_BIT))
545 
546 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
547 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
548 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
549 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
550 
551 static inline void __set_pte_at(struct mm_struct *mm,
552 				unsigned long __always_unused addr,
553 				pte_t *ptep, pte_t pte, unsigned int nr)
554 {
555 	__sync_cache_and_tags(pte, nr);
556 	__check_safe_pte_update(mm, ptep, pte);
557 	__set_pte(ptep, pte);
558 }
559 
560 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
561 			      pmd_t *pmdp, pmd_t pmd)
562 {
563 	page_table_check_pmd_set(mm, pmdp, pmd);
564 	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd),
565 						PMD_SIZE >> PAGE_SHIFT);
566 }
567 
568 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
569 			      pud_t *pudp, pud_t pud)
570 {
571 	page_table_check_pud_set(mm, pudp, pud);
572 	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud),
573 						PUD_SIZE >> PAGE_SHIFT);
574 }
575 
576 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
577 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
578 
579 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
580 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
581 
582 #define __pgprot_modify(prot,mask,bits) \
583 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
584 
585 #define pgprot_nx(prot) \
586 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
587 
588 /*
589  * Mark the prot value as uncacheable and unbufferable.
590  */
591 #define pgprot_noncached(prot) \
592 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
593 #define pgprot_writecombine(prot) \
594 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
595 #define pgprot_device(prot) \
596 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
597 #define pgprot_tagged(prot) \
598 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
599 #define pgprot_mhp	pgprot_tagged
600 /*
601  * DMA allocations for non-coherent devices use what the Arm architecture calls
602  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
603  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
604  * is intended for MMIO and thus forbids speculation, preserves access size,
605  * requires strict alignment and can also force write responses to come from the
606  * endpoint.
607  */
608 #define pgprot_dmacoherent(prot) \
609 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
610 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
611 
612 #define __HAVE_PHYS_MEM_ACCESS_PROT
613 struct file;
614 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
615 				     unsigned long size, pgprot_t vma_prot);
616 
617 #define pmd_none(pmd)		(!pmd_val(pmd))
618 
619 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
620 				 PMD_TYPE_TABLE)
621 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
622 				 PMD_TYPE_SECT)
623 #define pmd_leaf(pmd)		(pmd_present(pmd) && !pmd_table(pmd))
624 #define pmd_bad(pmd)		(!pmd_table(pmd))
625 
626 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
627 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
628 
629 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
630 static inline bool pud_sect(pud_t pud) { return false; }
631 static inline bool pud_table(pud_t pud) { return true; }
632 #else
633 #define pud_sect(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
634 				 PUD_TYPE_SECT)
635 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
636 				 PUD_TYPE_TABLE)
637 #endif
638 
639 extern pgd_t init_pg_dir[];
640 extern pgd_t init_pg_end[];
641 extern pgd_t swapper_pg_dir[];
642 extern pgd_t idmap_pg_dir[];
643 extern pgd_t tramp_pg_dir[];
644 extern pgd_t reserved_pg_dir[];
645 
646 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
647 
648 static inline bool in_swapper_pgdir(void *addr)
649 {
650 	return ((unsigned long)addr & PAGE_MASK) ==
651 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
652 }
653 
654 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
655 {
656 #ifdef __PAGETABLE_PMD_FOLDED
657 	if (in_swapper_pgdir(pmdp)) {
658 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
659 		return;
660 	}
661 #endif /* __PAGETABLE_PMD_FOLDED */
662 
663 	WRITE_ONCE(*pmdp, pmd);
664 
665 	if (pmd_valid(pmd)) {
666 		dsb(ishst);
667 		isb();
668 	}
669 }
670 
671 static inline void pmd_clear(pmd_t *pmdp)
672 {
673 	set_pmd(pmdp, __pmd(0));
674 }
675 
676 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
677 {
678 	return __pmd_to_phys(pmd);
679 }
680 
681 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
682 {
683 	return (unsigned long)__va(pmd_page_paddr(pmd));
684 }
685 
686 /* Find an entry in the third-level page table. */
687 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
688 
689 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
690 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
691 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
692 
693 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
694 
695 /* use ONLY for statically allocated translation tables */
696 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
697 
698 /*
699  * Conversion functions: convert a page and protection to a page entry,
700  * and a page entry and page directory to the page they refer to.
701  */
702 #define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
703 
704 #if CONFIG_PGTABLE_LEVELS > 2
705 
706 #define pmd_ERROR(e)	\
707 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
708 
709 #define pud_none(pud)		(!pud_val(pud))
710 #define pud_bad(pud)		(!pud_table(pud))
711 #define pud_present(pud)	pte_present(pud_pte(pud))
712 #define pud_leaf(pud)		(pud_present(pud) && !pud_table(pud))
713 #define pud_valid(pud)		pte_valid(pud_pte(pud))
714 #define pud_user(pud)		pte_user(pud_pte(pud))
715 #define pud_user_exec(pud)	pte_user_exec(pud_pte(pud))
716 
717 static inline bool pgtable_l4_enabled(void);
718 
719 static inline void set_pud(pud_t *pudp, pud_t pud)
720 {
721 	if (!pgtable_l4_enabled() && in_swapper_pgdir(pudp)) {
722 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
723 		return;
724 	}
725 
726 	WRITE_ONCE(*pudp, pud);
727 
728 	if (pud_valid(pud)) {
729 		dsb(ishst);
730 		isb();
731 	}
732 }
733 
734 static inline void pud_clear(pud_t *pudp)
735 {
736 	set_pud(pudp, __pud(0));
737 }
738 
739 static inline phys_addr_t pud_page_paddr(pud_t pud)
740 {
741 	return __pud_to_phys(pud);
742 }
743 
744 static inline pmd_t *pud_pgtable(pud_t pud)
745 {
746 	return (pmd_t *)__va(pud_page_paddr(pud));
747 }
748 
749 /* Find an entry in the second-level page table. */
750 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
751 
752 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
753 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
754 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
755 
756 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
757 
758 /* use ONLY for statically allocated translation tables */
759 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
760 
761 #else
762 
763 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
764 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
765 
766 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
767 #define pmd_set_fixmap(addr)		NULL
768 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
769 #define pmd_clear_fixmap()
770 
771 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
772 
773 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
774 
775 #if CONFIG_PGTABLE_LEVELS > 3
776 
777 static __always_inline bool pgtable_l4_enabled(void)
778 {
779 	if (CONFIG_PGTABLE_LEVELS > 4 || !IS_ENABLED(CONFIG_ARM64_LPA2))
780 		return true;
781 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
782 		return vabits_actual == VA_BITS;
783 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
784 }
785 
786 static inline bool mm_pud_folded(const struct mm_struct *mm)
787 {
788 	return !pgtable_l4_enabled();
789 }
790 #define mm_pud_folded  mm_pud_folded
791 
792 #define pud_ERROR(e)	\
793 	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
794 
795 #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
796 #define p4d_bad(p4d)		(pgtable_l4_enabled() && !(p4d_val(p4d) & 2))
797 #define p4d_present(p4d)	(!p4d_none(p4d))
798 
799 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
800 {
801 	if (in_swapper_pgdir(p4dp)) {
802 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
803 		return;
804 	}
805 
806 	WRITE_ONCE(*p4dp, p4d);
807 	dsb(ishst);
808 	isb();
809 }
810 
811 static inline void p4d_clear(p4d_t *p4dp)
812 {
813 	if (pgtable_l4_enabled())
814 		set_p4d(p4dp, __p4d(0));
815 }
816 
817 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
818 {
819 	return __p4d_to_phys(p4d);
820 }
821 
822 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
823 
824 static inline pud_t *p4d_to_folded_pud(p4d_t *p4dp, unsigned long addr)
825 {
826 	return (pud_t *)PTR_ALIGN_DOWN(p4dp, PAGE_SIZE) + pud_index(addr);
827 }
828 
829 static inline pud_t *p4d_pgtable(p4d_t p4d)
830 {
831 	return (pud_t *)__va(p4d_page_paddr(p4d));
832 }
833 
834 static inline phys_addr_t pud_offset_phys(p4d_t *p4dp, unsigned long addr)
835 {
836 	BUG_ON(!pgtable_l4_enabled());
837 
838 	return p4d_page_paddr(READ_ONCE(*p4dp)) + pud_index(addr) * sizeof(pud_t);
839 }
840 
841 static inline
842 pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long addr)
843 {
844 	if (!pgtable_l4_enabled())
845 		return p4d_to_folded_pud(p4dp, addr);
846 	return (pud_t *)__va(p4d_page_paddr(p4d)) + pud_index(addr);
847 }
848 #define pud_offset_lockless pud_offset_lockless
849 
850 static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long addr)
851 {
852 	return pud_offset_lockless(p4dp, READ_ONCE(*p4dp), addr);
853 }
854 #define pud_offset	pud_offset
855 
856 static inline pud_t *pud_set_fixmap(unsigned long addr)
857 {
858 	if (!pgtable_l4_enabled())
859 		return NULL;
860 	return (pud_t *)set_fixmap_offset(FIX_PUD, addr);
861 }
862 
863 static inline pud_t *pud_set_fixmap_offset(p4d_t *p4dp, unsigned long addr)
864 {
865 	if (!pgtable_l4_enabled())
866 		return p4d_to_folded_pud(p4dp, addr);
867 	return pud_set_fixmap(pud_offset_phys(p4dp, addr));
868 }
869 
870 static inline void pud_clear_fixmap(void)
871 {
872 	if (pgtable_l4_enabled())
873 		clear_fixmap(FIX_PUD);
874 }
875 
876 /* use ONLY for statically allocated translation tables */
877 static inline pud_t *pud_offset_kimg(p4d_t *p4dp, u64 addr)
878 {
879 	if (!pgtable_l4_enabled())
880 		return p4d_to_folded_pud(p4dp, addr);
881 	return (pud_t *)__phys_to_kimg(pud_offset_phys(p4dp, addr));
882 }
883 
884 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
885 
886 #else
887 
888 static inline bool pgtable_l4_enabled(void) { return false; }
889 
890 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
891 
892 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
893 #define pud_set_fixmap(addr)		NULL
894 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
895 #define pud_clear_fixmap()
896 
897 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
898 
899 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
900 
901 #if CONFIG_PGTABLE_LEVELS > 4
902 
903 static __always_inline bool pgtable_l5_enabled(void)
904 {
905 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
906 		return vabits_actual == VA_BITS;
907 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
908 }
909 
910 static inline bool mm_p4d_folded(const struct mm_struct *mm)
911 {
912 	return !pgtable_l5_enabled();
913 }
914 #define mm_p4d_folded  mm_p4d_folded
915 
916 #define p4d_ERROR(e)	\
917 	pr_err("%s:%d: bad p4d %016llx.\n", __FILE__, __LINE__, p4d_val(e))
918 
919 #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
920 #define pgd_bad(pgd)		(pgtable_l5_enabled() && !(pgd_val(pgd) & 2))
921 #define pgd_present(pgd)	(!pgd_none(pgd))
922 
923 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
924 {
925 	if (in_swapper_pgdir(pgdp)) {
926 		set_swapper_pgd(pgdp, __pgd(pgd_val(pgd)));
927 		return;
928 	}
929 
930 	WRITE_ONCE(*pgdp, pgd);
931 	dsb(ishst);
932 	isb();
933 }
934 
935 static inline void pgd_clear(pgd_t *pgdp)
936 {
937 	if (pgtable_l5_enabled())
938 		set_pgd(pgdp, __pgd(0));
939 }
940 
941 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
942 {
943 	return __pgd_to_phys(pgd);
944 }
945 
946 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
947 
948 static inline p4d_t *pgd_to_folded_p4d(pgd_t *pgdp, unsigned long addr)
949 {
950 	return (p4d_t *)PTR_ALIGN_DOWN(pgdp, PAGE_SIZE) + p4d_index(addr);
951 }
952 
953 static inline phys_addr_t p4d_offset_phys(pgd_t *pgdp, unsigned long addr)
954 {
955 	BUG_ON(!pgtable_l5_enabled());
956 
957 	return pgd_page_paddr(READ_ONCE(*pgdp)) + p4d_index(addr) * sizeof(p4d_t);
958 }
959 
960 static inline
961 p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
962 {
963 	if (!pgtable_l5_enabled())
964 		return pgd_to_folded_p4d(pgdp, addr);
965 	return (p4d_t *)__va(pgd_page_paddr(pgd)) + p4d_index(addr);
966 }
967 #define p4d_offset_lockless p4d_offset_lockless
968 
969 static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long addr)
970 {
971 	return p4d_offset_lockless(pgdp, READ_ONCE(*pgdp), addr);
972 }
973 
974 static inline p4d_t *p4d_set_fixmap(unsigned long addr)
975 {
976 	if (!pgtable_l5_enabled())
977 		return NULL;
978 	return (p4d_t *)set_fixmap_offset(FIX_P4D, addr);
979 }
980 
981 static inline p4d_t *p4d_set_fixmap_offset(pgd_t *pgdp, unsigned long addr)
982 {
983 	if (!pgtable_l5_enabled())
984 		return pgd_to_folded_p4d(pgdp, addr);
985 	return p4d_set_fixmap(p4d_offset_phys(pgdp, addr));
986 }
987 
988 static inline void p4d_clear_fixmap(void)
989 {
990 	if (pgtable_l5_enabled())
991 		clear_fixmap(FIX_P4D);
992 }
993 
994 /* use ONLY for statically allocated translation tables */
995 static inline p4d_t *p4d_offset_kimg(pgd_t *pgdp, u64 addr)
996 {
997 	if (!pgtable_l5_enabled())
998 		return pgd_to_folded_p4d(pgdp, addr);
999 	return (p4d_t *)__phys_to_kimg(p4d_offset_phys(pgdp, addr));
1000 }
1001 
1002 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
1003 
1004 #else
1005 
1006 static inline bool pgtable_l5_enabled(void) { return false; }
1007 
1008 /* Match p4d_offset folding in <asm/generic/pgtable-nop4d.h> */
1009 #define p4d_set_fixmap(addr)		NULL
1010 #define p4d_set_fixmap_offset(p4dp, addr)	((p4d_t *)p4dp)
1011 #define p4d_clear_fixmap()
1012 
1013 #define p4d_offset_kimg(dir,addr)	((p4d_t *)dir)
1014 
1015 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
1016 
1017 #define pgd_ERROR(e)	\
1018 	pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
1019 
1020 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
1021 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
1022 
1023 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
1024 {
1025 	/*
1026 	 * Normal and Normal-Tagged are two different memory types and indices
1027 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
1028 	 */
1029 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
1030 			      PTE_PROT_NONE | PTE_VALID | PTE_WRITE | PTE_GP |
1031 			      PTE_ATTRINDX_MASK;
1032 	/* preserve the hardware dirty information */
1033 	if (pte_hw_dirty(pte))
1034 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
1035 
1036 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
1037 	/*
1038 	 * If we end up clearing hw dirtiness for a sw-dirty PTE, set hardware
1039 	 * dirtiness again.
1040 	 */
1041 	if (pte_sw_dirty(pte))
1042 		pte = pte_mkdirty(pte);
1043 	return pte;
1044 }
1045 
1046 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1047 {
1048 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
1049 }
1050 
1051 extern int __ptep_set_access_flags(struct vm_area_struct *vma,
1052 				 unsigned long address, pte_t *ptep,
1053 				 pte_t entry, int dirty);
1054 
1055 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1056 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1057 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1058 					unsigned long address, pmd_t *pmdp,
1059 					pmd_t entry, int dirty)
1060 {
1061 	return __ptep_set_access_flags(vma, address, (pte_t *)pmdp,
1062 							pmd_pte(entry), dirty);
1063 }
1064 
1065 static inline int pud_devmap(pud_t pud)
1066 {
1067 	return 0;
1068 }
1069 
1070 static inline int pgd_devmap(pgd_t pgd)
1071 {
1072 	return 0;
1073 }
1074 #endif
1075 
1076 #ifdef CONFIG_PAGE_TABLE_CHECK
1077 static inline bool pte_user_accessible_page(pte_t pte)
1078 {
1079 	return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte));
1080 }
1081 
1082 static inline bool pmd_user_accessible_page(pmd_t pmd)
1083 {
1084 	return pmd_leaf(pmd) && !pmd_present_invalid(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
1085 }
1086 
1087 static inline bool pud_user_accessible_page(pud_t pud)
1088 {
1089 	return pud_leaf(pud) && (pud_user(pud) || pud_user_exec(pud));
1090 }
1091 #endif
1092 
1093 /*
1094  * Atomic pte/pmd modifications.
1095  */
1096 static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma,
1097 					      unsigned long address,
1098 					      pte_t *ptep)
1099 {
1100 	pte_t old_pte, pte;
1101 
1102 	pte = __ptep_get(ptep);
1103 	do {
1104 		old_pte = pte;
1105 		pte = pte_mkold(pte);
1106 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1107 					       pte_val(old_pte), pte_val(pte));
1108 	} while (pte_val(pte) != pte_val(old_pte));
1109 
1110 	return pte_young(pte);
1111 }
1112 
1113 static inline int __ptep_clear_flush_young(struct vm_area_struct *vma,
1114 					 unsigned long address, pte_t *ptep)
1115 {
1116 	int young = __ptep_test_and_clear_young(vma, address, ptep);
1117 
1118 	if (young) {
1119 		/*
1120 		 * We can elide the trailing DSB here since the worst that can
1121 		 * happen is that a CPU continues to use the young entry in its
1122 		 * TLB and we mistakenly reclaim the associated page. The
1123 		 * window for such an event is bounded by the next
1124 		 * context-switch, which provides a DSB to complete the TLB
1125 		 * invalidation.
1126 		 */
1127 		flush_tlb_page_nosync(vma, address);
1128 	}
1129 
1130 	return young;
1131 }
1132 
1133 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1134 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1135 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
1136 					    unsigned long address,
1137 					    pmd_t *pmdp)
1138 {
1139 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
1140 }
1141 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1142 
1143 static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
1144 				       unsigned long address, pte_t *ptep)
1145 {
1146 	pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
1147 
1148 	page_table_check_pte_clear(mm, pte);
1149 
1150 	return pte;
1151 }
1152 
1153 static inline void __clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1154 				pte_t *ptep, unsigned int nr, int full)
1155 {
1156 	for (;;) {
1157 		__ptep_get_and_clear(mm, addr, ptep);
1158 		if (--nr == 0)
1159 			break;
1160 		ptep++;
1161 		addr += PAGE_SIZE;
1162 	}
1163 }
1164 
1165 static inline pte_t __get_and_clear_full_ptes(struct mm_struct *mm,
1166 				unsigned long addr, pte_t *ptep,
1167 				unsigned int nr, int full)
1168 {
1169 	pte_t pte, tmp_pte;
1170 
1171 	pte = __ptep_get_and_clear(mm, addr, ptep);
1172 	while (--nr) {
1173 		ptep++;
1174 		addr += PAGE_SIZE;
1175 		tmp_pte = __ptep_get_and_clear(mm, addr, ptep);
1176 		if (pte_dirty(tmp_pte))
1177 			pte = pte_mkdirty(pte);
1178 		if (pte_young(tmp_pte))
1179 			pte = pte_mkyoung(pte);
1180 	}
1181 	return pte;
1182 }
1183 
1184 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1185 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1186 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1187 					    unsigned long address, pmd_t *pmdp)
1188 {
1189 	pmd_t pmd = __pmd(xchg_relaxed(&pmd_val(*pmdp), 0));
1190 
1191 	page_table_check_pmd_clear(mm, pmd);
1192 
1193 	return pmd;
1194 }
1195 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1196 
1197 static inline void ___ptep_set_wrprotect(struct mm_struct *mm,
1198 					unsigned long address, pte_t *ptep,
1199 					pte_t pte)
1200 {
1201 	pte_t old_pte;
1202 
1203 	do {
1204 		old_pte = pte;
1205 		pte = pte_wrprotect(pte);
1206 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1207 					       pte_val(old_pte), pte_val(pte));
1208 	} while (pte_val(pte) != pte_val(old_pte));
1209 }
1210 
1211 /*
1212  * __ptep_set_wrprotect - mark read-only while trasferring potential hardware
1213  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
1214  */
1215 static inline void __ptep_set_wrprotect(struct mm_struct *mm,
1216 					unsigned long address, pte_t *ptep)
1217 {
1218 	___ptep_set_wrprotect(mm, address, ptep, __ptep_get(ptep));
1219 }
1220 
1221 static inline void __wrprotect_ptes(struct mm_struct *mm, unsigned long address,
1222 				pte_t *ptep, unsigned int nr)
1223 {
1224 	unsigned int i;
1225 
1226 	for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++)
1227 		__ptep_set_wrprotect(mm, address, ptep);
1228 }
1229 
1230 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1231 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1232 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1233 				      unsigned long address, pmd_t *pmdp)
1234 {
1235 	__ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
1236 }
1237 
1238 #define pmdp_establish pmdp_establish
1239 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1240 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1241 {
1242 	page_table_check_pmd_set(vma->vm_mm, pmdp, pmd);
1243 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
1244 }
1245 #endif
1246 
1247 /*
1248  * Encode and decode a swap entry:
1249  *	bits 0-1:	present (must be zero)
1250  *	bits 2:		remember PG_anon_exclusive
1251  *	bits 3-7:	swap type
1252  *	bits 8-57:	swap offset
1253  *	bit  58:	PTE_PROT_NONE (must be zero)
1254  */
1255 #define __SWP_TYPE_SHIFT	3
1256 #define __SWP_TYPE_BITS		5
1257 #define __SWP_OFFSET_BITS	50
1258 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
1259 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
1260 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
1261 
1262 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
1263 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
1264 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
1265 
1266 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1267 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
1268 
1269 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1270 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
1271 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
1272 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
1273 
1274 /*
1275  * Ensure that there are not more swap files than can be encoded in the kernel
1276  * PTEs.
1277  */
1278 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
1279 
1280 #ifdef CONFIG_ARM64_MTE
1281 
1282 #define __HAVE_ARCH_PREPARE_TO_SWAP
1283 static inline int arch_prepare_to_swap(struct page *page)
1284 {
1285 	if (system_supports_mte())
1286 		return mte_save_tags(page);
1287 	return 0;
1288 }
1289 
1290 #define __HAVE_ARCH_SWAP_INVALIDATE
1291 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
1292 {
1293 	if (system_supports_mte())
1294 		mte_invalidate_tags(type, offset);
1295 }
1296 
1297 static inline void arch_swap_invalidate_area(int type)
1298 {
1299 	if (system_supports_mte())
1300 		mte_invalidate_tags_area(type);
1301 }
1302 
1303 #define __HAVE_ARCH_SWAP_RESTORE
1304 static inline void arch_swap_restore(swp_entry_t entry, struct folio *folio)
1305 {
1306 	if (system_supports_mte())
1307 		mte_restore_tags(entry, &folio->page);
1308 }
1309 
1310 #endif /* CONFIG_ARM64_MTE */
1311 
1312 /*
1313  * On AArch64, the cache coherency is handled via the __set_ptes() function.
1314  */
1315 static inline void update_mmu_cache_range(struct vm_fault *vmf,
1316 		struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
1317 		unsigned int nr)
1318 {
1319 	/*
1320 	 * We don't do anything here, so there's a very small chance of
1321 	 * us retaking a user fault which we just fixed up. The alternative
1322 	 * is doing a dsb(ishst), but that penalises the fastpath.
1323 	 */
1324 }
1325 
1326 #define update_mmu_cache(vma, addr, ptep) \
1327 	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
1328 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
1329 
1330 #ifdef CONFIG_ARM64_PA_BITS_52
1331 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
1332 #else
1333 #define phys_to_ttbr(addr)	(addr)
1334 #endif
1335 
1336 /*
1337  * On arm64 without hardware Access Flag, copying from user will fail because
1338  * the pte is old and cannot be marked young. So we always end up with zeroed
1339  * page after fork() + CoW for pfn mappings. We don't always have a
1340  * hardware-managed access flag on arm64.
1341  */
1342 #define arch_has_hw_pte_young		cpu_has_hw_af
1343 
1344 /*
1345  * Experimentally, it's cheap to set the access flag in hardware and we
1346  * benefit from prefaulting mappings as 'old' to start with.
1347  */
1348 #define arch_wants_old_prefaulted_pte	cpu_has_hw_af
1349 
1350 static inline bool pud_sect_supported(void)
1351 {
1352 	return PAGE_SIZE == SZ_4K;
1353 }
1354 
1355 
1356 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
1357 #define ptep_modify_prot_start ptep_modify_prot_start
1358 extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
1359 				    unsigned long addr, pte_t *ptep);
1360 
1361 #define ptep_modify_prot_commit ptep_modify_prot_commit
1362 extern void ptep_modify_prot_commit(struct vm_area_struct *vma,
1363 				    unsigned long addr, pte_t *ptep,
1364 				    pte_t old_pte, pte_t new_pte);
1365 
1366 #ifdef CONFIG_ARM64_CONTPTE
1367 
1368 /*
1369  * The contpte APIs are used to transparently manage the contiguous bit in ptes
1370  * where it is possible and makes sense to do so. The PTE_CONT bit is considered
1371  * a private implementation detail of the public ptep API (see below).
1372  */
1373 extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
1374 				pte_t *ptep, pte_t pte);
1375 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
1376 				pte_t *ptep, pte_t pte);
1377 extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
1378 extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
1379 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
1380 				pte_t *ptep, pte_t pte, unsigned int nr);
1381 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1382 				pte_t *ptep, unsigned int nr, int full);
1383 extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
1384 				unsigned long addr, pte_t *ptep,
1385 				unsigned int nr, int full);
1386 extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
1387 				unsigned long addr, pte_t *ptep);
1388 extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
1389 				unsigned long addr, pte_t *ptep);
1390 extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
1391 				pte_t *ptep, unsigned int nr);
1392 extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
1393 				unsigned long addr, pte_t *ptep,
1394 				pte_t entry, int dirty);
1395 
1396 static __always_inline void contpte_try_fold(struct mm_struct *mm,
1397 				unsigned long addr, pte_t *ptep, pte_t pte)
1398 {
1399 	/*
1400 	 * Only bother trying if both the virtual and physical addresses are
1401 	 * aligned and correspond to the last entry in a contig range. The core
1402 	 * code mostly modifies ranges from low to high, so this is the likely
1403 	 * the last modification in the contig range, so a good time to fold.
1404 	 * We can't fold special mappings, because there is no associated folio.
1405 	 */
1406 
1407 	const unsigned long contmask = CONT_PTES - 1;
1408 	bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
1409 
1410 	if (unlikely(valign)) {
1411 		bool palign = (pte_pfn(pte) & contmask) == contmask;
1412 
1413 		if (unlikely(palign &&
1414 		    pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)))
1415 			__contpte_try_fold(mm, addr, ptep, pte);
1416 	}
1417 }
1418 
1419 static __always_inline void contpte_try_unfold(struct mm_struct *mm,
1420 				unsigned long addr, pte_t *ptep, pte_t pte)
1421 {
1422 	if (unlikely(pte_valid_cont(pte)))
1423 		__contpte_try_unfold(mm, addr, ptep, pte);
1424 }
1425 
1426 #define pte_batch_hint pte_batch_hint
1427 static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
1428 {
1429 	if (!pte_valid_cont(pte))
1430 		return 1;
1431 
1432 	return CONT_PTES - (((unsigned long)ptep >> 3) & (CONT_PTES - 1));
1433 }
1434 
1435 /*
1436  * The below functions constitute the public API that arm64 presents to the
1437  * core-mm to manipulate PTE entries within their page tables (or at least this
1438  * is the subset of the API that arm64 needs to implement). These public
1439  * versions will automatically and transparently apply the contiguous bit where
1440  * it makes sense to do so. Therefore any users that are contig-aware (e.g.
1441  * hugetlb, kernel mapper) should NOT use these APIs, but instead use the
1442  * private versions, which are prefixed with double underscore. All of these
1443  * APIs except for ptep_get_lockless() are expected to be called with the PTL
1444  * held. Although the contiguous bit is considered private to the
1445  * implementation, it is deliberately allowed to leak through the getters (e.g.
1446  * ptep_get()), back to core code. This is required so that pte_leaf_size() can
1447  * provide an accurate size for perf_get_pgtable_size(). But this leakage means
1448  * its possible a pte will be passed to a setter with the contiguous bit set, so
1449  * we explicitly clear the contiguous bit in those cases to prevent accidentally
1450  * setting it in the pgtable.
1451  */
1452 
1453 #define ptep_get ptep_get
1454 static inline pte_t ptep_get(pte_t *ptep)
1455 {
1456 	pte_t pte = __ptep_get(ptep);
1457 
1458 	if (likely(!pte_valid_cont(pte)))
1459 		return pte;
1460 
1461 	return contpte_ptep_get(ptep, pte);
1462 }
1463 
1464 #define ptep_get_lockless ptep_get_lockless
1465 static inline pte_t ptep_get_lockless(pte_t *ptep)
1466 {
1467 	pte_t pte = __ptep_get(ptep);
1468 
1469 	if (likely(!pte_valid_cont(pte)))
1470 		return pte;
1471 
1472 	return contpte_ptep_get_lockless(ptep);
1473 }
1474 
1475 static inline void set_pte(pte_t *ptep, pte_t pte)
1476 {
1477 	/*
1478 	 * We don't have the mm or vaddr so cannot unfold contig entries (since
1479 	 * it requires tlb maintenance). set_pte() is not used in core code, so
1480 	 * this should never even be called. Regardless do our best to service
1481 	 * any call and emit a warning if there is any attempt to set a pte on
1482 	 * top of an existing contig range.
1483 	 */
1484 	pte_t orig_pte = __ptep_get(ptep);
1485 
1486 	WARN_ON_ONCE(pte_valid_cont(orig_pte));
1487 	__set_pte(ptep, pte_mknoncont(pte));
1488 }
1489 
1490 #define set_ptes set_ptes
1491 static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
1492 				pte_t *ptep, pte_t pte, unsigned int nr)
1493 {
1494 	pte = pte_mknoncont(pte);
1495 
1496 	if (likely(nr == 1)) {
1497 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1498 		__set_ptes(mm, addr, ptep, pte, 1);
1499 		contpte_try_fold(mm, addr, ptep, pte);
1500 	} else {
1501 		contpte_set_ptes(mm, addr, ptep, pte, nr);
1502 	}
1503 }
1504 
1505 static inline void pte_clear(struct mm_struct *mm,
1506 				unsigned long addr, pte_t *ptep)
1507 {
1508 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1509 	__pte_clear(mm, addr, ptep);
1510 }
1511 
1512 #define clear_full_ptes clear_full_ptes
1513 static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1514 				pte_t *ptep, unsigned int nr, int full)
1515 {
1516 	if (likely(nr == 1)) {
1517 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1518 		__clear_full_ptes(mm, addr, ptep, nr, full);
1519 	} else {
1520 		contpte_clear_full_ptes(mm, addr, ptep, nr, full);
1521 	}
1522 }
1523 
1524 #define get_and_clear_full_ptes get_and_clear_full_ptes
1525 static inline pte_t get_and_clear_full_ptes(struct mm_struct *mm,
1526 				unsigned long addr, pte_t *ptep,
1527 				unsigned int nr, int full)
1528 {
1529 	pte_t pte;
1530 
1531 	if (likely(nr == 1)) {
1532 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1533 		pte = __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1534 	} else {
1535 		pte = contpte_get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1536 	}
1537 
1538 	return pte;
1539 }
1540 
1541 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1542 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
1543 				unsigned long addr, pte_t *ptep)
1544 {
1545 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1546 	return __ptep_get_and_clear(mm, addr, ptep);
1547 }
1548 
1549 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1550 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
1551 				unsigned long addr, pte_t *ptep)
1552 {
1553 	pte_t orig_pte = __ptep_get(ptep);
1554 
1555 	if (likely(!pte_valid_cont(orig_pte)))
1556 		return __ptep_test_and_clear_young(vma, addr, ptep);
1557 
1558 	return contpte_ptep_test_and_clear_young(vma, addr, ptep);
1559 }
1560 
1561 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1562 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
1563 				unsigned long addr, pte_t *ptep)
1564 {
1565 	pte_t orig_pte = __ptep_get(ptep);
1566 
1567 	if (likely(!pte_valid_cont(orig_pte)))
1568 		return __ptep_clear_flush_young(vma, addr, ptep);
1569 
1570 	return contpte_ptep_clear_flush_young(vma, addr, ptep);
1571 }
1572 
1573 #define wrprotect_ptes wrprotect_ptes
1574 static __always_inline void wrprotect_ptes(struct mm_struct *mm,
1575 				unsigned long addr, pte_t *ptep, unsigned int nr)
1576 {
1577 	if (likely(nr == 1)) {
1578 		/*
1579 		 * Optimization: wrprotect_ptes() can only be called for present
1580 		 * ptes so we only need to check contig bit as condition for
1581 		 * unfold, and we can remove the contig bit from the pte we read
1582 		 * to avoid re-reading. This speeds up fork() which is sensitive
1583 		 * for order-0 folios. Equivalent to contpte_try_unfold().
1584 		 */
1585 		pte_t orig_pte = __ptep_get(ptep);
1586 
1587 		if (unlikely(pte_cont(orig_pte))) {
1588 			__contpte_try_unfold(mm, addr, ptep, orig_pte);
1589 			orig_pte = pte_mknoncont(orig_pte);
1590 		}
1591 		___ptep_set_wrprotect(mm, addr, ptep, orig_pte);
1592 	} else {
1593 		contpte_wrprotect_ptes(mm, addr, ptep, nr);
1594 	}
1595 }
1596 
1597 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1598 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1599 				unsigned long addr, pte_t *ptep)
1600 {
1601 	wrprotect_ptes(mm, addr, ptep, 1);
1602 }
1603 
1604 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1605 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
1606 				unsigned long addr, pte_t *ptep,
1607 				pte_t entry, int dirty)
1608 {
1609 	pte_t orig_pte = __ptep_get(ptep);
1610 
1611 	entry = pte_mknoncont(entry);
1612 
1613 	if (likely(!pte_valid_cont(orig_pte)))
1614 		return __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1615 
1616 	return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1617 }
1618 
1619 #else /* CONFIG_ARM64_CONTPTE */
1620 
1621 #define ptep_get				__ptep_get
1622 #define set_pte					__set_pte
1623 #define set_ptes				__set_ptes
1624 #define pte_clear				__pte_clear
1625 #define clear_full_ptes				__clear_full_ptes
1626 #define get_and_clear_full_ptes			__get_and_clear_full_ptes
1627 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1628 #define ptep_get_and_clear			__ptep_get_and_clear
1629 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1630 #define ptep_test_and_clear_young		__ptep_test_and_clear_young
1631 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1632 #define ptep_clear_flush_young			__ptep_clear_flush_young
1633 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1634 #define ptep_set_wrprotect			__ptep_set_wrprotect
1635 #define wrprotect_ptes				__wrprotect_ptes
1636 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1637 #define ptep_set_access_flags			__ptep_set_access_flags
1638 
1639 #endif /* CONFIG_ARM64_CONTPTE */
1640 
1641 #endif /* !__ASSEMBLY__ */
1642 
1643 #endif /* __ASM_PGTABLE_H */
1644