xref: /linux/arch/arm64/include/asm/pgtable.h (revision 9557b4376d02088a33e5f4116bcc324d35a3b64c)
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_valid(pte) || pte_present_invalid(pte))
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 #define pte_present_invalid(pte) \
130 	((pte_val(pte) & (PTE_VALID | PTE_PRESENT_INVALID)) == PTE_PRESENT_INVALID)
131 /*
132  * Execute-only user mappings do not have the PTE_USER bit set. All valid
133  * kernel mappings have the PTE_UXN bit set.
134  */
135 #define pte_valid_not_user(pte) \
136 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
137 /*
138  * Returns true if the pte is valid and has the contiguous bit set.
139  */
140 #define pte_valid_cont(pte)	(pte_valid(pte) && pte_cont(pte))
141 /*
142  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
143  * so that we don't erroneously return false for pages that have been
144  * remapped as PROT_NONE but are yet to be flushed from the TLB.
145  * Note that we can't make any assumptions based on the state of the access
146  * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the
147  * TLB.
148  */
149 #define pte_accessible(mm, pte)	\
150 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
151 
152 /*
153  * p??_access_permitted() is true for valid user mappings (PTE_USER
154  * bit set, subject to the write permission check). For execute-only
155  * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
156  * not set) must return false. PROT_NONE mappings do not have the
157  * PTE_VALID bit set.
158  */
159 #define pte_access_permitted(pte, write) \
160 	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
161 #define pmd_access_permitted(pmd, write) \
162 	(pte_access_permitted(pmd_pte(pmd), (write)))
163 #define pud_access_permitted(pud, write) \
164 	(pte_access_permitted(pud_pte(pud), (write)))
165 
166 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
167 {
168 	pte_val(pte) &= ~pgprot_val(prot);
169 	return pte;
170 }
171 
172 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
173 {
174 	pte_val(pte) |= pgprot_val(prot);
175 	return pte;
176 }
177 
178 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
179 {
180 	pmd_val(pmd) &= ~pgprot_val(prot);
181 	return pmd;
182 }
183 
184 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
185 {
186 	pmd_val(pmd) |= pgprot_val(prot);
187 	return pmd;
188 }
189 
190 static inline pte_t pte_mkwrite_novma(pte_t pte)
191 {
192 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
193 	pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
194 	return pte;
195 }
196 
197 static inline pte_t pte_mkclean(pte_t pte)
198 {
199 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
200 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
201 
202 	return pte;
203 }
204 
205 static inline pte_t pte_mkdirty(pte_t pte)
206 {
207 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
208 
209 	if (pte_write(pte))
210 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
211 
212 	return pte;
213 }
214 
215 static inline pte_t pte_wrprotect(pte_t pte)
216 {
217 	/*
218 	 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
219 	 * clear), set the PTE_DIRTY bit.
220 	 */
221 	if (pte_hw_dirty(pte))
222 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
223 
224 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
225 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
226 	return pte;
227 }
228 
229 static inline pte_t pte_mkold(pte_t pte)
230 {
231 	return clear_pte_bit(pte, __pgprot(PTE_AF));
232 }
233 
234 static inline pte_t pte_mkyoung(pte_t pte)
235 {
236 	return set_pte_bit(pte, __pgprot(PTE_AF));
237 }
238 
239 static inline pte_t pte_mkspecial(pte_t pte)
240 {
241 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
242 }
243 
244 static inline pte_t pte_mkcont(pte_t pte)
245 {
246 	pte = set_pte_bit(pte, __pgprot(PTE_CONT));
247 	return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
248 }
249 
250 static inline pte_t pte_mknoncont(pte_t pte)
251 {
252 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
253 }
254 
255 static inline pte_t pte_mkpresent(pte_t pte)
256 {
257 	return set_pte_bit(pte, __pgprot(PTE_VALID));
258 }
259 
260 static inline pte_t pte_mkinvalid(pte_t pte)
261 {
262 	pte = set_pte_bit(pte, __pgprot(PTE_PRESENT_INVALID));
263 	pte = clear_pte_bit(pte, __pgprot(PTE_VALID));
264 	return pte;
265 }
266 
267 static inline pmd_t pmd_mkcont(pmd_t pmd)
268 {
269 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
270 }
271 
272 static inline pte_t pte_mkdevmap(pte_t pte)
273 {
274 	return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL));
275 }
276 
277 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
278 static inline int pte_uffd_wp(pte_t pte)
279 {
280 	return !!(pte_val(pte) & PTE_UFFD_WP);
281 }
282 
283 static inline pte_t pte_mkuffd_wp(pte_t pte)
284 {
285 	return pte_wrprotect(set_pte_bit(pte, __pgprot(PTE_UFFD_WP)));
286 }
287 
288 static inline pte_t pte_clear_uffd_wp(pte_t pte)
289 {
290 	return clear_pte_bit(pte, __pgprot(PTE_UFFD_WP));
291 }
292 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
293 
294 static inline void __set_pte_nosync(pte_t *ptep, pte_t pte)
295 {
296 	WRITE_ONCE(*ptep, pte);
297 }
298 
299 static inline void __set_pte(pte_t *ptep, pte_t pte)
300 {
301 	__set_pte_nosync(ptep, pte);
302 
303 	/*
304 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
305 	 * or update_mmu_cache() have the necessary barriers.
306 	 */
307 	if (pte_valid_not_user(pte)) {
308 		dsb(ishst);
309 		isb();
310 	}
311 }
312 
313 static inline pte_t __ptep_get(pte_t *ptep)
314 {
315 	return READ_ONCE(*ptep);
316 }
317 
318 extern void __sync_icache_dcache(pte_t pteval);
319 bool pgattr_change_is_safe(u64 old, u64 new);
320 
321 /*
322  * PTE bits configuration in the presence of hardware Dirty Bit Management
323  * (PTE_WRITE == PTE_DBM):
324  *
325  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
326  *   0      0      |   1           0          0
327  *   0      1      |   1           1          0
328  *   1      0      |   1           0          1
329  *   1      1      |   0           1          x
330  *
331  * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
332  * the page fault mechanism. Checking the dirty status of a pte becomes:
333  *
334  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
335  */
336 
337 static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep,
338 					   pte_t pte)
339 {
340 	pte_t old_pte;
341 
342 	if (!IS_ENABLED(CONFIG_DEBUG_VM))
343 		return;
344 
345 	old_pte = __ptep_get(ptep);
346 
347 	if (!pte_valid(old_pte) || !pte_valid(pte))
348 		return;
349 	if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
350 		return;
351 
352 	/*
353 	 * Check for potential race with hardware updates of the pte
354 	 * (__ptep_set_access_flags safely changes valid ptes without going
355 	 * through an invalid entry).
356 	 */
357 	VM_WARN_ONCE(!pte_young(pte),
358 		     "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
359 		     __func__, pte_val(old_pte), pte_val(pte));
360 	VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
361 		     "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
362 		     __func__, pte_val(old_pte), pte_val(pte));
363 	VM_WARN_ONCE(!pgattr_change_is_safe(pte_val(old_pte), pte_val(pte)),
364 		     "%s: unsafe attribute change: 0x%016llx -> 0x%016llx",
365 		     __func__, pte_val(old_pte), pte_val(pte));
366 }
367 
368 static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages)
369 {
370 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
371 		__sync_icache_dcache(pte);
372 
373 	/*
374 	 * If the PTE would provide user space access to the tags associated
375 	 * with it then ensure that the MTE tags are synchronised.  Although
376 	 * pte_access_permitted() returns false for exec only mappings, they
377 	 * don't expose tags (instruction fetches don't check tags).
378 	 */
379 	if (system_supports_mte() && pte_access_permitted(pte, false) &&
380 	    !pte_special(pte) && pte_tagged(pte))
381 		mte_sync_tags(pte, nr_pages);
382 }
383 
384 /*
385  * Select all bits except the pfn
386  */
387 static inline pgprot_t pte_pgprot(pte_t pte)
388 {
389 	unsigned long pfn = pte_pfn(pte);
390 
391 	return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
392 }
393 
394 #define pte_advance_pfn pte_advance_pfn
395 static inline pte_t pte_advance_pfn(pte_t pte, unsigned long nr)
396 {
397 	return pfn_pte(pte_pfn(pte) + nr, pte_pgprot(pte));
398 }
399 
400 static inline void __set_ptes(struct mm_struct *mm,
401 			      unsigned long __always_unused addr,
402 			      pte_t *ptep, pte_t pte, unsigned int nr)
403 {
404 	page_table_check_ptes_set(mm, ptep, pte, nr);
405 	__sync_cache_and_tags(pte, nr);
406 
407 	for (;;) {
408 		__check_safe_pte_update(mm, ptep, pte);
409 		__set_pte(ptep, pte);
410 		if (--nr == 0)
411 			break;
412 		ptep++;
413 		pte = pte_advance_pfn(pte, 1);
414 	}
415 }
416 
417 /*
418  * Huge pte definitions.
419  */
420 #define pte_mkhuge(pte)		(__pte(pte_val(pte) & ~PTE_TABLE_BIT))
421 
422 /*
423  * Hugetlb definitions.
424  */
425 #define HUGE_MAX_HSTATE		4
426 #define HPAGE_SHIFT		PMD_SHIFT
427 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
428 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
429 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
430 
431 static inline pte_t pgd_pte(pgd_t pgd)
432 {
433 	return __pte(pgd_val(pgd));
434 }
435 
436 static inline pte_t p4d_pte(p4d_t p4d)
437 {
438 	return __pte(p4d_val(p4d));
439 }
440 
441 static inline pte_t pud_pte(pud_t pud)
442 {
443 	return __pte(pud_val(pud));
444 }
445 
446 static inline pud_t pte_pud(pte_t pte)
447 {
448 	return __pud(pte_val(pte));
449 }
450 
451 static inline pmd_t pud_pmd(pud_t pud)
452 {
453 	return __pmd(pud_val(pud));
454 }
455 
456 static inline pte_t pmd_pte(pmd_t pmd)
457 {
458 	return __pte(pmd_val(pmd));
459 }
460 
461 static inline pmd_t pte_pmd(pte_t pte)
462 {
463 	return __pmd(pte_val(pte));
464 }
465 
466 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
467 {
468 	return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT);
469 }
470 
471 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
472 {
473 	return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
474 }
475 
476 static inline pte_t pte_swp_mkexclusive(pte_t pte)
477 {
478 	return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
479 }
480 
481 static inline int pte_swp_exclusive(pte_t pte)
482 {
483 	return pte_val(pte) & PTE_SWP_EXCLUSIVE;
484 }
485 
486 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
487 {
488 	return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
489 }
490 
491 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
492 static inline pte_t pte_swp_mkuffd_wp(pte_t pte)
493 {
494 	return set_pte_bit(pte, __pgprot(PTE_SWP_UFFD_WP));
495 }
496 
497 static inline int pte_swp_uffd_wp(pte_t pte)
498 {
499 	return !!(pte_val(pte) & PTE_SWP_UFFD_WP);
500 }
501 
502 static inline pte_t pte_swp_clear_uffd_wp(pte_t pte)
503 {
504 	return clear_pte_bit(pte, __pgprot(PTE_SWP_UFFD_WP));
505 }
506 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
507 
508 #ifdef CONFIG_NUMA_BALANCING
509 /*
510  * See the comment in include/linux/pgtable.h
511  */
512 static inline int pte_protnone(pte_t pte)
513 {
514 	/*
515 	 * pte_present_invalid() tells us that the pte is invalid from HW
516 	 * perspective but present from SW perspective, so the fields are to be
517 	 * interpretted as per the HW layout. The second 2 checks are the unique
518 	 * encoding that we use for PROT_NONE. It is insufficient to only use
519 	 * the first check because we share the same encoding scheme with pmds
520 	 * which support pmd_mkinvalid(), so can be present-invalid without
521 	 * being PROT_NONE.
522 	 */
523 	return pte_present_invalid(pte) && !pte_user(pte) && !pte_user_exec(pte);
524 }
525 
526 static inline int pmd_protnone(pmd_t pmd)
527 {
528 	return pte_protnone(pmd_pte(pmd));
529 }
530 #endif
531 
532 #define pmd_present(pmd)	pte_present(pmd_pte(pmd))
533 
534 /*
535  * THP definitions.
536  */
537 
538 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
539 static inline int pmd_trans_huge(pmd_t pmd)
540 {
541 	return pmd_val(pmd) && pmd_present(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
542 }
543 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
544 
545 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
546 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
547 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
548 #define pmd_user(pmd)		pte_user(pmd_pte(pmd))
549 #define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
550 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
551 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
552 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
553 #define pmd_mkwrite_novma(pmd)	pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)))
554 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
555 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
556 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
557 #define pmd_mkinvalid(pmd)	pte_pmd(pte_mkinvalid(pmd_pte(pmd)))
558 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
559 #define pmd_uffd_wp(pmd)	pte_uffd_wp(pmd_pte(pmd))
560 #define pmd_mkuffd_wp(pmd)	pte_pmd(pte_mkuffd_wp(pmd_pte(pmd)))
561 #define pmd_clear_uffd_wp(pmd)	pte_pmd(pte_clear_uffd_wp(pmd_pte(pmd)))
562 #define pmd_swp_uffd_wp(pmd)	pte_swp_uffd_wp(pmd_pte(pmd))
563 #define pmd_swp_mkuffd_wp(pmd)	pte_pmd(pte_swp_mkuffd_wp(pmd_pte(pmd)))
564 #define pmd_swp_clear_uffd_wp(pmd) \
565 				pte_pmd(pte_swp_clear_uffd_wp(pmd_pte(pmd)))
566 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
567 
568 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
569 
570 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
571 
572 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
573 #define pmd_devmap(pmd)		pte_devmap(pmd_pte(pmd))
574 #endif
575 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
576 {
577 	return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP)));
578 }
579 
580 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
581 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
582 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
583 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
584 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
585 
586 #define pud_young(pud)		pte_young(pud_pte(pud))
587 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
588 #define pud_write(pud)		pte_write(pud_pte(pud))
589 
590 #define pud_mkhuge(pud)		(__pud(pud_val(pud) & ~PUD_TABLE_BIT))
591 
592 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
593 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
594 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
595 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
596 
597 static inline void __set_pte_at(struct mm_struct *mm,
598 				unsigned long __always_unused addr,
599 				pte_t *ptep, pte_t pte, unsigned int nr)
600 {
601 	__sync_cache_and_tags(pte, nr);
602 	__check_safe_pte_update(mm, ptep, pte);
603 	__set_pte(ptep, pte);
604 }
605 
606 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
607 			      pmd_t *pmdp, pmd_t pmd)
608 {
609 	page_table_check_pmd_set(mm, pmdp, pmd);
610 	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd),
611 						PMD_SIZE >> PAGE_SHIFT);
612 }
613 
614 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
615 			      pud_t *pudp, pud_t pud)
616 {
617 	page_table_check_pud_set(mm, pudp, pud);
618 	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud),
619 						PUD_SIZE >> PAGE_SHIFT);
620 }
621 
622 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
623 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
624 
625 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
626 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
627 
628 #define __pgprot_modify(prot,mask,bits) \
629 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
630 
631 #define pgprot_nx(prot) \
632 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
633 
634 /*
635  * Mark the prot value as uncacheable and unbufferable.
636  */
637 #define pgprot_noncached(prot) \
638 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
639 #define pgprot_writecombine(prot) \
640 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
641 #define pgprot_device(prot) \
642 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
643 #define pgprot_tagged(prot) \
644 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
645 #define pgprot_mhp	pgprot_tagged
646 /*
647  * DMA allocations for non-coherent devices use what the Arm architecture calls
648  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
649  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
650  * is intended for MMIO and thus forbids speculation, preserves access size,
651  * requires strict alignment and can also force write responses to come from the
652  * endpoint.
653  */
654 #define pgprot_dmacoherent(prot) \
655 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
656 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
657 
658 #define __HAVE_PHYS_MEM_ACCESS_PROT
659 struct file;
660 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
661 				     unsigned long size, pgprot_t vma_prot);
662 
663 #define pmd_none(pmd)		(!pmd_val(pmd))
664 
665 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
666 				 PMD_TYPE_TABLE)
667 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
668 				 PMD_TYPE_SECT)
669 #define pmd_leaf(pmd)		(pmd_present(pmd) && !pmd_table(pmd))
670 #define pmd_bad(pmd)		(!pmd_table(pmd))
671 
672 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
673 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
674 
675 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
676 static inline bool pud_sect(pud_t pud) { return false; }
677 static inline bool pud_table(pud_t pud) { return true; }
678 #else
679 #define pud_sect(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
680 				 PUD_TYPE_SECT)
681 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
682 				 PUD_TYPE_TABLE)
683 #endif
684 
685 extern pgd_t init_pg_dir[];
686 extern pgd_t init_pg_end[];
687 extern pgd_t swapper_pg_dir[];
688 extern pgd_t idmap_pg_dir[];
689 extern pgd_t tramp_pg_dir[];
690 extern pgd_t reserved_pg_dir[];
691 
692 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
693 
694 static inline bool in_swapper_pgdir(void *addr)
695 {
696 	return ((unsigned long)addr & PAGE_MASK) ==
697 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
698 }
699 
700 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
701 {
702 #ifdef __PAGETABLE_PMD_FOLDED
703 	if (in_swapper_pgdir(pmdp)) {
704 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
705 		return;
706 	}
707 #endif /* __PAGETABLE_PMD_FOLDED */
708 
709 	WRITE_ONCE(*pmdp, pmd);
710 
711 	if (pmd_valid(pmd)) {
712 		dsb(ishst);
713 		isb();
714 	}
715 }
716 
717 static inline void pmd_clear(pmd_t *pmdp)
718 {
719 	set_pmd(pmdp, __pmd(0));
720 }
721 
722 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
723 {
724 	return __pmd_to_phys(pmd);
725 }
726 
727 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
728 {
729 	return (unsigned long)__va(pmd_page_paddr(pmd));
730 }
731 
732 /* Find an entry in the third-level page table. */
733 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
734 
735 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
736 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
737 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
738 
739 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
740 
741 /* use ONLY for statically allocated translation tables */
742 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
743 
744 /*
745  * Conversion functions: convert a page and protection to a page entry,
746  * and a page entry and page directory to the page they refer to.
747  */
748 #define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
749 
750 #if CONFIG_PGTABLE_LEVELS > 2
751 
752 #define pmd_ERROR(e)	\
753 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
754 
755 #define pud_none(pud)		(!pud_val(pud))
756 #define pud_bad(pud)		(!pud_table(pud))
757 #define pud_present(pud)	pte_present(pud_pte(pud))
758 #ifndef __PAGETABLE_PMD_FOLDED
759 #define pud_leaf(pud)		(pud_present(pud) && !pud_table(pud))
760 #else
761 #define pud_leaf(pud)		false
762 #endif
763 #define pud_valid(pud)		pte_valid(pud_pte(pud))
764 #define pud_user(pud)		pte_user(pud_pte(pud))
765 #define pud_user_exec(pud)	pte_user_exec(pud_pte(pud))
766 
767 static inline bool pgtable_l4_enabled(void);
768 
769 static inline void set_pud(pud_t *pudp, pud_t pud)
770 {
771 	if (!pgtable_l4_enabled() && in_swapper_pgdir(pudp)) {
772 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
773 		return;
774 	}
775 
776 	WRITE_ONCE(*pudp, pud);
777 
778 	if (pud_valid(pud)) {
779 		dsb(ishst);
780 		isb();
781 	}
782 }
783 
784 static inline void pud_clear(pud_t *pudp)
785 {
786 	set_pud(pudp, __pud(0));
787 }
788 
789 static inline phys_addr_t pud_page_paddr(pud_t pud)
790 {
791 	return __pud_to_phys(pud);
792 }
793 
794 static inline pmd_t *pud_pgtable(pud_t pud)
795 {
796 	return (pmd_t *)__va(pud_page_paddr(pud));
797 }
798 
799 /* Find an entry in the second-level page table. */
800 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
801 
802 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
803 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
804 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
805 
806 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
807 
808 /* use ONLY for statically allocated translation tables */
809 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
810 
811 #else
812 
813 #define pud_valid(pud)		false
814 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
815 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
816 
817 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
818 #define pmd_set_fixmap(addr)		NULL
819 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
820 #define pmd_clear_fixmap()
821 
822 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
823 
824 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
825 
826 #if CONFIG_PGTABLE_LEVELS > 3
827 
828 static __always_inline bool pgtable_l4_enabled(void)
829 {
830 	if (CONFIG_PGTABLE_LEVELS > 4 || !IS_ENABLED(CONFIG_ARM64_LPA2))
831 		return true;
832 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
833 		return vabits_actual == VA_BITS;
834 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
835 }
836 
837 static inline bool mm_pud_folded(const struct mm_struct *mm)
838 {
839 	return !pgtable_l4_enabled();
840 }
841 #define mm_pud_folded  mm_pud_folded
842 
843 #define pud_ERROR(e)	\
844 	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
845 
846 #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
847 #define p4d_bad(p4d)		(pgtable_l4_enabled() && !(p4d_val(p4d) & 2))
848 #define p4d_present(p4d)	(!p4d_none(p4d))
849 
850 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
851 {
852 	if (in_swapper_pgdir(p4dp)) {
853 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
854 		return;
855 	}
856 
857 	WRITE_ONCE(*p4dp, p4d);
858 	dsb(ishst);
859 	isb();
860 }
861 
862 static inline void p4d_clear(p4d_t *p4dp)
863 {
864 	if (pgtable_l4_enabled())
865 		set_p4d(p4dp, __p4d(0));
866 }
867 
868 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
869 {
870 	return __p4d_to_phys(p4d);
871 }
872 
873 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
874 
875 static inline pud_t *p4d_to_folded_pud(p4d_t *p4dp, unsigned long addr)
876 {
877 	return (pud_t *)PTR_ALIGN_DOWN(p4dp, PAGE_SIZE) + pud_index(addr);
878 }
879 
880 static inline pud_t *p4d_pgtable(p4d_t p4d)
881 {
882 	return (pud_t *)__va(p4d_page_paddr(p4d));
883 }
884 
885 static inline phys_addr_t pud_offset_phys(p4d_t *p4dp, unsigned long addr)
886 {
887 	BUG_ON(!pgtable_l4_enabled());
888 
889 	return p4d_page_paddr(READ_ONCE(*p4dp)) + pud_index(addr) * sizeof(pud_t);
890 }
891 
892 static inline
893 pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long addr)
894 {
895 	if (!pgtable_l4_enabled())
896 		return p4d_to_folded_pud(p4dp, addr);
897 	return (pud_t *)__va(p4d_page_paddr(p4d)) + pud_index(addr);
898 }
899 #define pud_offset_lockless pud_offset_lockless
900 
901 static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long addr)
902 {
903 	return pud_offset_lockless(p4dp, READ_ONCE(*p4dp), addr);
904 }
905 #define pud_offset	pud_offset
906 
907 static inline pud_t *pud_set_fixmap(unsigned long addr)
908 {
909 	if (!pgtable_l4_enabled())
910 		return NULL;
911 	return (pud_t *)set_fixmap_offset(FIX_PUD, addr);
912 }
913 
914 static inline pud_t *pud_set_fixmap_offset(p4d_t *p4dp, unsigned long addr)
915 {
916 	if (!pgtable_l4_enabled())
917 		return p4d_to_folded_pud(p4dp, addr);
918 	return pud_set_fixmap(pud_offset_phys(p4dp, addr));
919 }
920 
921 static inline void pud_clear_fixmap(void)
922 {
923 	if (pgtable_l4_enabled())
924 		clear_fixmap(FIX_PUD);
925 }
926 
927 /* use ONLY for statically allocated translation tables */
928 static inline pud_t *pud_offset_kimg(p4d_t *p4dp, u64 addr)
929 {
930 	if (!pgtable_l4_enabled())
931 		return p4d_to_folded_pud(p4dp, addr);
932 	return (pud_t *)__phys_to_kimg(pud_offset_phys(p4dp, addr));
933 }
934 
935 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
936 
937 #else
938 
939 static inline bool pgtable_l4_enabled(void) { return false; }
940 
941 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
942 
943 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
944 #define pud_set_fixmap(addr)		NULL
945 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
946 #define pud_clear_fixmap()
947 
948 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
949 
950 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
951 
952 #if CONFIG_PGTABLE_LEVELS > 4
953 
954 static __always_inline bool pgtable_l5_enabled(void)
955 {
956 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
957 		return vabits_actual == VA_BITS;
958 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
959 }
960 
961 static inline bool mm_p4d_folded(const struct mm_struct *mm)
962 {
963 	return !pgtable_l5_enabled();
964 }
965 #define mm_p4d_folded  mm_p4d_folded
966 
967 #define p4d_ERROR(e)	\
968 	pr_err("%s:%d: bad p4d %016llx.\n", __FILE__, __LINE__, p4d_val(e))
969 
970 #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
971 #define pgd_bad(pgd)		(pgtable_l5_enabled() && !(pgd_val(pgd) & 2))
972 #define pgd_present(pgd)	(!pgd_none(pgd))
973 
974 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
975 {
976 	if (in_swapper_pgdir(pgdp)) {
977 		set_swapper_pgd(pgdp, __pgd(pgd_val(pgd)));
978 		return;
979 	}
980 
981 	WRITE_ONCE(*pgdp, pgd);
982 	dsb(ishst);
983 	isb();
984 }
985 
986 static inline void pgd_clear(pgd_t *pgdp)
987 {
988 	if (pgtable_l5_enabled())
989 		set_pgd(pgdp, __pgd(0));
990 }
991 
992 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
993 {
994 	return __pgd_to_phys(pgd);
995 }
996 
997 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
998 
999 static inline p4d_t *pgd_to_folded_p4d(pgd_t *pgdp, unsigned long addr)
1000 {
1001 	return (p4d_t *)PTR_ALIGN_DOWN(pgdp, PAGE_SIZE) + p4d_index(addr);
1002 }
1003 
1004 static inline phys_addr_t p4d_offset_phys(pgd_t *pgdp, unsigned long addr)
1005 {
1006 	BUG_ON(!pgtable_l5_enabled());
1007 
1008 	return pgd_page_paddr(READ_ONCE(*pgdp)) + p4d_index(addr) * sizeof(p4d_t);
1009 }
1010 
1011 static inline
1012 p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1013 {
1014 	if (!pgtable_l5_enabled())
1015 		return pgd_to_folded_p4d(pgdp, addr);
1016 	return (p4d_t *)__va(pgd_page_paddr(pgd)) + p4d_index(addr);
1017 }
1018 #define p4d_offset_lockless p4d_offset_lockless
1019 
1020 static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long addr)
1021 {
1022 	return p4d_offset_lockless(pgdp, READ_ONCE(*pgdp), addr);
1023 }
1024 
1025 static inline p4d_t *p4d_set_fixmap(unsigned long addr)
1026 {
1027 	if (!pgtable_l5_enabled())
1028 		return NULL;
1029 	return (p4d_t *)set_fixmap_offset(FIX_P4D, addr);
1030 }
1031 
1032 static inline p4d_t *p4d_set_fixmap_offset(pgd_t *pgdp, unsigned long addr)
1033 {
1034 	if (!pgtable_l5_enabled())
1035 		return pgd_to_folded_p4d(pgdp, addr);
1036 	return p4d_set_fixmap(p4d_offset_phys(pgdp, addr));
1037 }
1038 
1039 static inline void p4d_clear_fixmap(void)
1040 {
1041 	if (pgtable_l5_enabled())
1042 		clear_fixmap(FIX_P4D);
1043 }
1044 
1045 /* use ONLY for statically allocated translation tables */
1046 static inline p4d_t *p4d_offset_kimg(pgd_t *pgdp, u64 addr)
1047 {
1048 	if (!pgtable_l5_enabled())
1049 		return pgd_to_folded_p4d(pgdp, addr);
1050 	return (p4d_t *)__phys_to_kimg(p4d_offset_phys(pgdp, addr));
1051 }
1052 
1053 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
1054 
1055 #else
1056 
1057 static inline bool pgtable_l5_enabled(void) { return false; }
1058 
1059 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1060 
1061 /* Match p4d_offset folding in <asm/generic/pgtable-nop4d.h> */
1062 #define p4d_set_fixmap(addr)		NULL
1063 #define p4d_set_fixmap_offset(p4dp, addr)	((p4d_t *)p4dp)
1064 #define p4d_clear_fixmap()
1065 
1066 #define p4d_offset_kimg(dir,addr)	((p4d_t *)dir)
1067 
1068 static inline
1069 p4d_t *p4d_offset_lockless_folded(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1070 {
1071 	/*
1072 	 * With runtime folding of the pud, pud_offset_lockless() passes
1073 	 * the 'pgd_t *' we return here to p4d_to_folded_pud(), which
1074 	 * will offset the pointer assuming that it points into
1075 	 * a page-table page. However, the fast GUP path passes us a
1076 	 * pgd_t allocated on the stack and so we must use the original
1077 	 * pointer in 'pgdp' to construct the p4d pointer instead of
1078 	 * using the generic p4d_offset_lockless() implementation.
1079 	 *
1080 	 * Note: reusing the original pointer means that we may
1081 	 * dereference the same (live) page-table entry multiple times.
1082 	 * This is safe because it is still only loaded once in the
1083 	 * context of each level and the CPU guarantees same-address
1084 	 * read-after-read ordering.
1085 	 */
1086 	return p4d_offset(pgdp, addr);
1087 }
1088 #define p4d_offset_lockless p4d_offset_lockless_folded
1089 
1090 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
1091 
1092 #define pgd_ERROR(e)	\
1093 	pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
1094 
1095 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
1096 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
1097 
1098 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
1099 {
1100 	/*
1101 	 * Normal and Normal-Tagged are two different memory types and indices
1102 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
1103 	 */
1104 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
1105 			      PTE_PRESENT_INVALID | PTE_VALID | PTE_WRITE |
1106 			      PTE_GP | PTE_ATTRINDX_MASK;
1107 	/* preserve the hardware dirty information */
1108 	if (pte_hw_dirty(pte))
1109 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
1110 
1111 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
1112 	/*
1113 	 * If we end up clearing hw dirtiness for a sw-dirty PTE, set hardware
1114 	 * dirtiness again.
1115 	 */
1116 	if (pte_sw_dirty(pte))
1117 		pte = pte_mkdirty(pte);
1118 	return pte;
1119 }
1120 
1121 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1122 {
1123 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
1124 }
1125 
1126 extern int __ptep_set_access_flags(struct vm_area_struct *vma,
1127 				 unsigned long address, pte_t *ptep,
1128 				 pte_t entry, int dirty);
1129 
1130 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1131 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1132 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1133 					unsigned long address, pmd_t *pmdp,
1134 					pmd_t entry, int dirty)
1135 {
1136 	return __ptep_set_access_flags(vma, address, (pte_t *)pmdp,
1137 							pmd_pte(entry), dirty);
1138 }
1139 
1140 static inline int pud_devmap(pud_t pud)
1141 {
1142 	return 0;
1143 }
1144 
1145 static inline int pgd_devmap(pgd_t pgd)
1146 {
1147 	return 0;
1148 }
1149 #endif
1150 
1151 #ifdef CONFIG_PAGE_TABLE_CHECK
1152 static inline bool pte_user_accessible_page(pte_t pte)
1153 {
1154 	return pte_valid(pte) && (pte_user(pte) || pte_user_exec(pte));
1155 }
1156 
1157 static inline bool pmd_user_accessible_page(pmd_t pmd)
1158 {
1159 	return pmd_valid(pmd) && !pmd_table(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
1160 }
1161 
1162 static inline bool pud_user_accessible_page(pud_t pud)
1163 {
1164 	return pud_valid(pud) && !pud_table(pud) && (pud_user(pud) || pud_user_exec(pud));
1165 }
1166 #endif
1167 
1168 /*
1169  * Atomic pte/pmd modifications.
1170  */
1171 static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma,
1172 					      unsigned long address,
1173 					      pte_t *ptep)
1174 {
1175 	pte_t old_pte, pte;
1176 
1177 	pte = __ptep_get(ptep);
1178 	do {
1179 		old_pte = pte;
1180 		pte = pte_mkold(pte);
1181 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1182 					       pte_val(old_pte), pte_val(pte));
1183 	} while (pte_val(pte) != pte_val(old_pte));
1184 
1185 	return pte_young(pte);
1186 }
1187 
1188 static inline int __ptep_clear_flush_young(struct vm_area_struct *vma,
1189 					 unsigned long address, pte_t *ptep)
1190 {
1191 	int young = __ptep_test_and_clear_young(vma, address, ptep);
1192 
1193 	if (young) {
1194 		/*
1195 		 * We can elide the trailing DSB here since the worst that can
1196 		 * happen is that a CPU continues to use the young entry in its
1197 		 * TLB and we mistakenly reclaim the associated page. The
1198 		 * window for such an event is bounded by the next
1199 		 * context-switch, which provides a DSB to complete the TLB
1200 		 * invalidation.
1201 		 */
1202 		flush_tlb_page_nosync(vma, address);
1203 	}
1204 
1205 	return young;
1206 }
1207 
1208 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1209 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1210 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
1211 					    unsigned long address,
1212 					    pmd_t *pmdp)
1213 {
1214 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
1215 }
1216 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1217 
1218 static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
1219 				       unsigned long address, pte_t *ptep)
1220 {
1221 	pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
1222 
1223 	page_table_check_pte_clear(mm, pte);
1224 
1225 	return pte;
1226 }
1227 
1228 static inline void __clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1229 				pte_t *ptep, unsigned int nr, int full)
1230 {
1231 	for (;;) {
1232 		__ptep_get_and_clear(mm, addr, ptep);
1233 		if (--nr == 0)
1234 			break;
1235 		ptep++;
1236 		addr += PAGE_SIZE;
1237 	}
1238 }
1239 
1240 static inline pte_t __get_and_clear_full_ptes(struct mm_struct *mm,
1241 				unsigned long addr, pte_t *ptep,
1242 				unsigned int nr, int full)
1243 {
1244 	pte_t pte, tmp_pte;
1245 
1246 	pte = __ptep_get_and_clear(mm, addr, ptep);
1247 	while (--nr) {
1248 		ptep++;
1249 		addr += PAGE_SIZE;
1250 		tmp_pte = __ptep_get_and_clear(mm, addr, ptep);
1251 		if (pte_dirty(tmp_pte))
1252 			pte = pte_mkdirty(pte);
1253 		if (pte_young(tmp_pte))
1254 			pte = pte_mkyoung(pte);
1255 	}
1256 	return pte;
1257 }
1258 
1259 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1260 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1261 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1262 					    unsigned long address, pmd_t *pmdp)
1263 {
1264 	pmd_t pmd = __pmd(xchg_relaxed(&pmd_val(*pmdp), 0));
1265 
1266 	page_table_check_pmd_clear(mm, pmd);
1267 
1268 	return pmd;
1269 }
1270 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1271 
1272 static inline void ___ptep_set_wrprotect(struct mm_struct *mm,
1273 					unsigned long address, pte_t *ptep,
1274 					pte_t pte)
1275 {
1276 	pte_t old_pte;
1277 
1278 	do {
1279 		old_pte = pte;
1280 		pte = pte_wrprotect(pte);
1281 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1282 					       pte_val(old_pte), pte_val(pte));
1283 	} while (pte_val(pte) != pte_val(old_pte));
1284 }
1285 
1286 /*
1287  * __ptep_set_wrprotect - mark read-only while trasferring potential hardware
1288  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
1289  */
1290 static inline void __ptep_set_wrprotect(struct mm_struct *mm,
1291 					unsigned long address, pte_t *ptep)
1292 {
1293 	___ptep_set_wrprotect(mm, address, ptep, __ptep_get(ptep));
1294 }
1295 
1296 static inline void __wrprotect_ptes(struct mm_struct *mm, unsigned long address,
1297 				pte_t *ptep, unsigned int nr)
1298 {
1299 	unsigned int i;
1300 
1301 	for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++)
1302 		__ptep_set_wrprotect(mm, address, ptep);
1303 }
1304 
1305 static inline void __clear_young_dirty_pte(struct vm_area_struct *vma,
1306 					   unsigned long addr, pte_t *ptep,
1307 					   pte_t pte, cydp_t flags)
1308 {
1309 	pte_t old_pte;
1310 
1311 	do {
1312 		old_pte = pte;
1313 
1314 		if (flags & CYDP_CLEAR_YOUNG)
1315 			pte = pte_mkold(pte);
1316 		if (flags & CYDP_CLEAR_DIRTY)
1317 			pte = pte_mkclean(pte);
1318 
1319 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1320 					       pte_val(old_pte), pte_val(pte));
1321 	} while (pte_val(pte) != pte_val(old_pte));
1322 }
1323 
1324 static inline void __clear_young_dirty_ptes(struct vm_area_struct *vma,
1325 					    unsigned long addr, pte_t *ptep,
1326 					    unsigned int nr, cydp_t flags)
1327 {
1328 	pte_t pte;
1329 
1330 	for (;;) {
1331 		pte = __ptep_get(ptep);
1332 
1333 		if (flags == (CYDP_CLEAR_YOUNG | CYDP_CLEAR_DIRTY))
1334 			__set_pte(ptep, pte_mkclean(pte_mkold(pte)));
1335 		else
1336 			__clear_young_dirty_pte(vma, addr, ptep, pte, flags);
1337 
1338 		if (--nr == 0)
1339 			break;
1340 		ptep++;
1341 		addr += PAGE_SIZE;
1342 	}
1343 }
1344 
1345 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1346 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1347 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1348 				      unsigned long address, pmd_t *pmdp)
1349 {
1350 	__ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
1351 }
1352 
1353 #define pmdp_establish pmdp_establish
1354 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1355 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1356 {
1357 	page_table_check_pmd_set(vma->vm_mm, pmdp, pmd);
1358 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
1359 }
1360 #endif
1361 
1362 /*
1363  * Encode and decode a swap entry:
1364  *	bits 0-1:	present (must be zero)
1365  *	bits 2:		remember PG_anon_exclusive
1366  *	bit  3:		remember uffd-wp state
1367  *	bits 6-10:	swap type
1368  *	bit  11:	PTE_PRESENT_INVALID (must be zero)
1369  *	bits 12-61:	swap offset
1370  */
1371 #define __SWP_TYPE_SHIFT	6
1372 #define __SWP_TYPE_BITS		5
1373 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
1374 #define __SWP_OFFSET_SHIFT	12
1375 #define __SWP_OFFSET_BITS	50
1376 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
1377 
1378 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
1379 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
1380 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
1381 
1382 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1383 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
1384 
1385 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1386 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
1387 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
1388 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
1389 
1390 /*
1391  * Ensure that there are not more swap files than can be encoded in the kernel
1392  * PTEs.
1393  */
1394 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
1395 
1396 #ifdef CONFIG_ARM64_MTE
1397 
1398 #define __HAVE_ARCH_PREPARE_TO_SWAP
1399 extern int arch_prepare_to_swap(struct folio *folio);
1400 
1401 #define __HAVE_ARCH_SWAP_INVALIDATE
1402 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
1403 {
1404 	if (system_supports_mte())
1405 		mte_invalidate_tags(type, offset);
1406 }
1407 
1408 static inline void arch_swap_invalidate_area(int type)
1409 {
1410 	if (system_supports_mte())
1411 		mte_invalidate_tags_area(type);
1412 }
1413 
1414 #define __HAVE_ARCH_SWAP_RESTORE
1415 extern void arch_swap_restore(swp_entry_t entry, struct folio *folio);
1416 
1417 #endif /* CONFIG_ARM64_MTE */
1418 
1419 /*
1420  * On AArch64, the cache coherency is handled via the __set_ptes() function.
1421  */
1422 static inline void update_mmu_cache_range(struct vm_fault *vmf,
1423 		struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
1424 		unsigned int nr)
1425 {
1426 	/*
1427 	 * We don't do anything here, so there's a very small chance of
1428 	 * us retaking a user fault which we just fixed up. The alternative
1429 	 * is doing a dsb(ishst), but that penalises the fastpath.
1430 	 */
1431 }
1432 
1433 #define update_mmu_cache(vma, addr, ptep) \
1434 	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
1435 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
1436 
1437 #ifdef CONFIG_ARM64_PA_BITS_52
1438 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
1439 #else
1440 #define phys_to_ttbr(addr)	(addr)
1441 #endif
1442 
1443 /*
1444  * On arm64 without hardware Access Flag, copying from user will fail because
1445  * the pte is old and cannot be marked young. So we always end up with zeroed
1446  * page after fork() + CoW for pfn mappings. We don't always have a
1447  * hardware-managed access flag on arm64.
1448  */
1449 #define arch_has_hw_pte_young		cpu_has_hw_af
1450 
1451 /*
1452  * Experimentally, it's cheap to set the access flag in hardware and we
1453  * benefit from prefaulting mappings as 'old' to start with.
1454  */
1455 #define arch_wants_old_prefaulted_pte	cpu_has_hw_af
1456 
1457 static inline bool pud_sect_supported(void)
1458 {
1459 	return PAGE_SIZE == SZ_4K;
1460 }
1461 
1462 
1463 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
1464 #define ptep_modify_prot_start ptep_modify_prot_start
1465 extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
1466 				    unsigned long addr, pte_t *ptep);
1467 
1468 #define ptep_modify_prot_commit ptep_modify_prot_commit
1469 extern void ptep_modify_prot_commit(struct vm_area_struct *vma,
1470 				    unsigned long addr, pte_t *ptep,
1471 				    pte_t old_pte, pte_t new_pte);
1472 
1473 #ifdef CONFIG_ARM64_CONTPTE
1474 
1475 /*
1476  * The contpte APIs are used to transparently manage the contiguous bit in ptes
1477  * where it is possible and makes sense to do so. The PTE_CONT bit is considered
1478  * a private implementation detail of the public ptep API (see below).
1479  */
1480 extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
1481 				pte_t *ptep, pte_t pte);
1482 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
1483 				pte_t *ptep, pte_t pte);
1484 extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
1485 extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
1486 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
1487 				pte_t *ptep, pte_t pte, unsigned int nr);
1488 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1489 				pte_t *ptep, unsigned int nr, int full);
1490 extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
1491 				unsigned long addr, pte_t *ptep,
1492 				unsigned int nr, int full);
1493 extern int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
1494 				unsigned long addr, pte_t *ptep);
1495 extern int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
1496 				unsigned long addr, pte_t *ptep);
1497 extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
1498 				pte_t *ptep, unsigned int nr);
1499 extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
1500 				unsigned long addr, pte_t *ptep,
1501 				pte_t entry, int dirty);
1502 extern void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
1503 				unsigned long addr, pte_t *ptep,
1504 				unsigned int nr, cydp_t flags);
1505 
1506 static __always_inline void contpte_try_fold(struct mm_struct *mm,
1507 				unsigned long addr, pte_t *ptep, pte_t pte)
1508 {
1509 	/*
1510 	 * Only bother trying if both the virtual and physical addresses are
1511 	 * aligned and correspond to the last entry in a contig range. The core
1512 	 * code mostly modifies ranges from low to high, so this is the likely
1513 	 * the last modification in the contig range, so a good time to fold.
1514 	 * We can't fold special mappings, because there is no associated folio.
1515 	 */
1516 
1517 	const unsigned long contmask = CONT_PTES - 1;
1518 	bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
1519 
1520 	if (unlikely(valign)) {
1521 		bool palign = (pte_pfn(pte) & contmask) == contmask;
1522 
1523 		if (unlikely(palign &&
1524 		    pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)))
1525 			__contpte_try_fold(mm, addr, ptep, pte);
1526 	}
1527 }
1528 
1529 static __always_inline void contpte_try_unfold(struct mm_struct *mm,
1530 				unsigned long addr, pte_t *ptep, pte_t pte)
1531 {
1532 	if (unlikely(pte_valid_cont(pte)))
1533 		__contpte_try_unfold(mm, addr, ptep, pte);
1534 }
1535 
1536 #define pte_batch_hint pte_batch_hint
1537 static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
1538 {
1539 	if (!pte_valid_cont(pte))
1540 		return 1;
1541 
1542 	return CONT_PTES - (((unsigned long)ptep >> 3) & (CONT_PTES - 1));
1543 }
1544 
1545 /*
1546  * The below functions constitute the public API that arm64 presents to the
1547  * core-mm to manipulate PTE entries within their page tables (or at least this
1548  * is the subset of the API that arm64 needs to implement). These public
1549  * versions will automatically and transparently apply the contiguous bit where
1550  * it makes sense to do so. Therefore any users that are contig-aware (e.g.
1551  * hugetlb, kernel mapper) should NOT use these APIs, but instead use the
1552  * private versions, which are prefixed with double underscore. All of these
1553  * APIs except for ptep_get_lockless() are expected to be called with the PTL
1554  * held. Although the contiguous bit is considered private to the
1555  * implementation, it is deliberately allowed to leak through the getters (e.g.
1556  * ptep_get()), back to core code. This is required so that pte_leaf_size() can
1557  * provide an accurate size for perf_get_pgtable_size(). But this leakage means
1558  * its possible a pte will be passed to a setter with the contiguous bit set, so
1559  * we explicitly clear the contiguous bit in those cases to prevent accidentally
1560  * setting it in the pgtable.
1561  */
1562 
1563 #define ptep_get ptep_get
1564 static inline pte_t ptep_get(pte_t *ptep)
1565 {
1566 	pte_t pte = __ptep_get(ptep);
1567 
1568 	if (likely(!pte_valid_cont(pte)))
1569 		return pte;
1570 
1571 	return contpte_ptep_get(ptep, pte);
1572 }
1573 
1574 #define ptep_get_lockless ptep_get_lockless
1575 static inline pte_t ptep_get_lockless(pte_t *ptep)
1576 {
1577 	pte_t pte = __ptep_get(ptep);
1578 
1579 	if (likely(!pte_valid_cont(pte)))
1580 		return pte;
1581 
1582 	return contpte_ptep_get_lockless(ptep);
1583 }
1584 
1585 static inline void set_pte(pte_t *ptep, pte_t pte)
1586 {
1587 	/*
1588 	 * We don't have the mm or vaddr so cannot unfold contig entries (since
1589 	 * it requires tlb maintenance). set_pte() is not used in core code, so
1590 	 * this should never even be called. Regardless do our best to service
1591 	 * any call and emit a warning if there is any attempt to set a pte on
1592 	 * top of an existing contig range.
1593 	 */
1594 	pte_t orig_pte = __ptep_get(ptep);
1595 
1596 	WARN_ON_ONCE(pte_valid_cont(orig_pte));
1597 	__set_pte(ptep, pte_mknoncont(pte));
1598 }
1599 
1600 #define set_ptes set_ptes
1601 static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
1602 				pte_t *ptep, pte_t pte, unsigned int nr)
1603 {
1604 	pte = pte_mknoncont(pte);
1605 
1606 	if (likely(nr == 1)) {
1607 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1608 		__set_ptes(mm, addr, ptep, pte, 1);
1609 		contpte_try_fold(mm, addr, ptep, pte);
1610 	} else {
1611 		contpte_set_ptes(mm, addr, ptep, pte, nr);
1612 	}
1613 }
1614 
1615 static inline void pte_clear(struct mm_struct *mm,
1616 				unsigned long addr, pte_t *ptep)
1617 {
1618 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1619 	__pte_clear(mm, addr, ptep);
1620 }
1621 
1622 #define clear_full_ptes clear_full_ptes
1623 static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1624 				pte_t *ptep, unsigned int nr, int full)
1625 {
1626 	if (likely(nr == 1)) {
1627 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1628 		__clear_full_ptes(mm, addr, ptep, nr, full);
1629 	} else {
1630 		contpte_clear_full_ptes(mm, addr, ptep, nr, full);
1631 	}
1632 }
1633 
1634 #define get_and_clear_full_ptes get_and_clear_full_ptes
1635 static inline pte_t get_and_clear_full_ptes(struct mm_struct *mm,
1636 				unsigned long addr, pte_t *ptep,
1637 				unsigned int nr, int full)
1638 {
1639 	pte_t pte;
1640 
1641 	if (likely(nr == 1)) {
1642 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1643 		pte = __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1644 	} else {
1645 		pte = contpte_get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1646 	}
1647 
1648 	return pte;
1649 }
1650 
1651 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1652 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
1653 				unsigned long addr, pte_t *ptep)
1654 {
1655 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1656 	return __ptep_get_and_clear(mm, addr, ptep);
1657 }
1658 
1659 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1660 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
1661 				unsigned long addr, pte_t *ptep)
1662 {
1663 	pte_t orig_pte = __ptep_get(ptep);
1664 
1665 	if (likely(!pte_valid_cont(orig_pte)))
1666 		return __ptep_test_and_clear_young(vma, addr, ptep);
1667 
1668 	return contpte_ptep_test_and_clear_young(vma, addr, ptep);
1669 }
1670 
1671 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1672 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
1673 				unsigned long addr, pte_t *ptep)
1674 {
1675 	pte_t orig_pte = __ptep_get(ptep);
1676 
1677 	if (likely(!pte_valid_cont(orig_pte)))
1678 		return __ptep_clear_flush_young(vma, addr, ptep);
1679 
1680 	return contpte_ptep_clear_flush_young(vma, addr, ptep);
1681 }
1682 
1683 #define wrprotect_ptes wrprotect_ptes
1684 static __always_inline void wrprotect_ptes(struct mm_struct *mm,
1685 				unsigned long addr, pte_t *ptep, unsigned int nr)
1686 {
1687 	if (likely(nr == 1)) {
1688 		/*
1689 		 * Optimization: wrprotect_ptes() can only be called for present
1690 		 * ptes so we only need to check contig bit as condition for
1691 		 * unfold, and we can remove the contig bit from the pte we read
1692 		 * to avoid re-reading. This speeds up fork() which is sensitive
1693 		 * for order-0 folios. Equivalent to contpte_try_unfold().
1694 		 */
1695 		pte_t orig_pte = __ptep_get(ptep);
1696 
1697 		if (unlikely(pte_cont(orig_pte))) {
1698 			__contpte_try_unfold(mm, addr, ptep, orig_pte);
1699 			orig_pte = pte_mknoncont(orig_pte);
1700 		}
1701 		___ptep_set_wrprotect(mm, addr, ptep, orig_pte);
1702 	} else {
1703 		contpte_wrprotect_ptes(mm, addr, ptep, nr);
1704 	}
1705 }
1706 
1707 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1708 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1709 				unsigned long addr, pte_t *ptep)
1710 {
1711 	wrprotect_ptes(mm, addr, ptep, 1);
1712 }
1713 
1714 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1715 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
1716 				unsigned long addr, pte_t *ptep,
1717 				pte_t entry, int dirty)
1718 {
1719 	pte_t orig_pte = __ptep_get(ptep);
1720 
1721 	entry = pte_mknoncont(entry);
1722 
1723 	if (likely(!pte_valid_cont(orig_pte)))
1724 		return __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1725 
1726 	return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1727 }
1728 
1729 #define clear_young_dirty_ptes clear_young_dirty_ptes
1730 static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
1731 					  unsigned long addr, pte_t *ptep,
1732 					  unsigned int nr, cydp_t flags)
1733 {
1734 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1735 		__clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1736 	else
1737 		contpte_clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1738 }
1739 
1740 #else /* CONFIG_ARM64_CONTPTE */
1741 
1742 #define ptep_get				__ptep_get
1743 #define set_pte					__set_pte
1744 #define set_ptes				__set_ptes
1745 #define pte_clear				__pte_clear
1746 #define clear_full_ptes				__clear_full_ptes
1747 #define get_and_clear_full_ptes			__get_and_clear_full_ptes
1748 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1749 #define ptep_get_and_clear			__ptep_get_and_clear
1750 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1751 #define ptep_test_and_clear_young		__ptep_test_and_clear_young
1752 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1753 #define ptep_clear_flush_young			__ptep_clear_flush_young
1754 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1755 #define ptep_set_wrprotect			__ptep_set_wrprotect
1756 #define wrprotect_ptes				__wrprotect_ptes
1757 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1758 #define ptep_set_access_flags			__ptep_set_access_flags
1759 #define clear_young_dirty_ptes			__clear_young_dirty_ptes
1760 
1761 #endif /* CONFIG_ARM64_CONTPTE */
1762 
1763 #endif /* !__ASSEMBLY__ */
1764 
1765 #endif /* __ASM_PGTABLE_H */
1766