xref: /linux/arch/arm64/include/asm/pgtable.h (revision 101fea09a860c7cd3ef53faefaab1f4a03132446)
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 __ASSEMBLER__
34 
35 #include <asm/cmpxchg.h>
36 #include <asm/fixmap.h>
37 #include <asm/por.h>
38 #include <linux/mmdebug.h>
39 #include <linux/mm_types.h>
40 #include <linux/sched.h>
41 #include <linux/page_table_check.h>
42 
43 static inline void emit_pte_barriers(void)
44 {
45 	/*
46 	 * These barriers are emitted under certain conditions after a pte entry
47 	 * was modified (see e.g. __set_pte_complete()). The dsb makes the store
48 	 * visible to the table walker. The isb ensures that any previous
49 	 * speculative "invalid translation" marker that is in the CPU's
50 	 * pipeline gets cleared, so that any access to that address after
51 	 * setting the pte to valid won't cause a spurious fault. If the thread
52 	 * gets preempted after storing to the pgtable but before emitting these
53 	 * barriers, __switch_to() emits a dsb which ensure the walker gets to
54 	 * see the store. There is no guarantee of an isb being issued though.
55 	 * This is safe because it will still get issued (albeit on a
56 	 * potentially different CPU) when the thread starts running again,
57 	 * before any access to the address.
58 	 */
59 	dsb(ishst);
60 	isb();
61 }
62 
63 static inline void queue_pte_barriers(void)
64 {
65 	if (is_lazy_mmu_mode_active()) {
66 		/* Avoid the atomic op if already set. */
67 		if (!test_thread_flag(TIF_LAZY_MMU_PENDING))
68 			set_thread_flag(TIF_LAZY_MMU_PENDING);
69 	} else {
70 		emit_pte_barriers();
71 	}
72 }
73 
74 static inline void arch_enter_lazy_mmu_mode(void) {}
75 
76 static inline void arch_flush_lazy_mmu_mode(void)
77 {
78 	if (test_and_clear_thread_flag(TIF_LAZY_MMU_PENDING))
79 		emit_pte_barriers();
80 }
81 
82 static inline void arch_leave_lazy_mmu_mode(void)
83 {
84 	arch_flush_lazy_mmu_mode();
85 }
86 
87 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
88 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
89 
90 /* Set stride and tlb_level in flush_*_tlb_range */
91 #define flush_pmd_tlb_range(vma, addr, end)	\
92 	__flush_tlb_range(vma, addr, end, PMD_SIZE, 2, TLBF_NONE)
93 #define flush_pud_tlb_range(vma, addr, end)	\
94 	__flush_tlb_range(vma, addr, end, PUD_SIZE, 1, TLBF_NONE)
95 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
96 
97 /*
98  * We use local TLB invalidation instruction when reusing page in
99  * write protection fault handler to avoid TLBI broadcast in the hot
100  * path.  This will cause spurious page faults if stale read-only TLB
101  * entries exist.
102  */
103 #define flush_tlb_fix_spurious_fault(vma, address, ptep)	\
104 	__flush_tlb_page(vma, address, TLBF_NOBROADCAST | TLBF_NONOTIFY)
105 
106 #define flush_tlb_fix_spurious_fault_pmd(vma, address, pmdp)			\
107 	__flush_tlb_range(vma, address, address + PMD_SIZE, PMD_SIZE, 2,	\
108 			  TLBF_NOBROADCAST | TLBF_NONOTIFY | TLBF_NOWALKCACHE)
109 
110 #ifdef CONFIG_ARM64_PA_BITS_52
111 static inline phys_addr_t __pte_to_phys(pte_t pte)
112 {
113 	pte_val(pte) &= ~PTE_MAYBE_SHARED;
114 	return (pte_val(pte) & PTE_ADDR_LOW) |
115 		((pte_val(pte) & PTE_ADDR_HIGH) << PTE_ADDR_HIGH_SHIFT);
116 }
117 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
118 {
119 	return (phys | (phys >> PTE_ADDR_HIGH_SHIFT)) & PHYS_TO_PTE_ADDR_MASK;
120 }
121 #else
122 static inline phys_addr_t __pte_to_phys(pte_t pte)
123 {
124 	return pte_val(pte) & PTE_ADDR_LOW;
125 }
126 
127 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
128 {
129 	return phys;
130 }
131 #endif
132 
133 #define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
134 #define pfn_pte(pfn,prot)	\
135 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
136 
137 #define pte_none(pte)		(!pte_val(pte))
138 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
139 
140 #define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))
141 #define pte_present_invalid(pte) \
142 	((pte_val(pte) & (PTE_VALID | PTE_PRESENT_INVALID)) == PTE_PRESENT_INVALID)
143 
144 /*
145  * The following only work if pte_present(). Undefined behaviour otherwise.
146  */
147 static __always_inline bool pte_present(pte_t pte)
148 {
149 	return pte_valid(pte) || pte_present_invalid(pte);
150 }
151 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
152 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
153 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
154 #define pte_rdonly(pte)		(!!(pte_val(pte) & PTE_RDONLY))
155 #define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
156 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
157 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
158 #define pte_tagged(pte)		((pte_val(pte) & PTE_ATTRINDX_MASK) == \
159 				 PTE_ATTRINDX(MT_NORMAL_TAGGED))
160 
161 #define pte_cont_addr_end(addr, end)						\
162 ({	unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK;	\
163 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
164 })
165 
166 #define pmd_cont_addr_end(addr, end)						\
167 ({	unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK;	\
168 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
169 })
170 
171 #define pte_hw_dirty(pte)	(pte_write(pte) && !pte_rdonly(pte))
172 #define pte_sw_dirty(pte)	(!!(pte_val(pte) & PTE_DIRTY))
173 #define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))
174 
175 /*
176  * Execute-only user mappings do not have the PTE_USER bit set. All valid
177  * kernel mappings have the PTE_UXN bit set.
178  */
179 #define pte_valid_not_user(pte) \
180 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
181 /*
182  * Returns true if the pte is valid and has the contiguous bit set.
183  */
184 #define pte_valid_cont(pte)	(pte_valid(pte) && pte_cont(pte))
185 /*
186  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
187  * so that we don't erroneously return false for pages that have been
188  * remapped as PROT_NONE but are yet to be flushed from the TLB.
189  * Note that we can't make any assumptions based on the state of the access
190  * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the
191  * TLB.
192  */
193 #define pte_accessible(mm, pte)	\
194 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
195 
196 static inline bool por_el0_allows_pkey(u8 pkey, bool write, bool execute)
197 {
198 	u64 por;
199 
200 	if (!system_supports_poe())
201 		return true;
202 
203 	por = read_sysreg_s(SYS_POR_EL0);
204 
205 	if (write)
206 		return por_elx_allows_write(por, pkey);
207 
208 	if (execute)
209 		return por_elx_allows_exec(por, pkey);
210 
211 	return por_elx_allows_read(por, pkey);
212 }
213 
214 /*
215  * p??_access_permitted() is true for valid user mappings (PTE_USER
216  * bit set, subject to the write permission check). For execute-only
217  * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
218  * not set) must return false. PROT_NONE mappings do not have the
219  * PTE_VALID bit set.
220  */
221 #define pte_access_permitted_no_overlay(pte, write) \
222 	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
223 #define pte_access_permitted(pte, write) \
224 	(pte_access_permitted_no_overlay(pte, write) && \
225 	por_el0_allows_pkey(FIELD_GET(PTE_PO_IDX_MASK, pte_val(pte)), write, false))
226 #define pmd_access_permitted(pmd, write) \
227 	(pte_access_permitted(pmd_pte(pmd), (write)))
228 #define pud_access_permitted(pud, write) \
229 	(pte_access_permitted(pud_pte(pud), (write)))
230 
231 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
232 {
233 	pte_val(pte) &= ~pgprot_val(prot);
234 	return pte;
235 }
236 
237 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
238 {
239 	pte_val(pte) |= pgprot_val(prot);
240 	return pte;
241 }
242 
243 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
244 {
245 	pmd_val(pmd) &= ~pgprot_val(prot);
246 	return pmd;
247 }
248 
249 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
250 {
251 	pmd_val(pmd) |= pgprot_val(prot);
252 	return pmd;
253 }
254 
255 static inline pte_t pte_mkwrite_novma(pte_t pte)
256 {
257 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
258 	if (pte_sw_dirty(pte))
259 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
260 	return pte;
261 }
262 
263 static inline pte_t pte_mkclean(pte_t pte)
264 {
265 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
266 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
267 
268 	return pte;
269 }
270 
271 static inline pte_t pte_mkdirty(pte_t pte)
272 {
273 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
274 
275 	if (pte_write(pte))
276 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
277 
278 	return pte;
279 }
280 
281 static inline pte_t pte_wrprotect(pte_t pte)
282 {
283 	/*
284 	 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
285 	 * clear), set the PTE_DIRTY bit.
286 	 */
287 	if (pte_hw_dirty(pte))
288 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
289 
290 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
291 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
292 	return pte;
293 }
294 
295 static inline pte_t pte_mkold(pte_t pte)
296 {
297 	return clear_pte_bit(pte, __pgprot(PTE_AF));
298 }
299 
300 static inline pte_t pte_mkyoung(pte_t pte)
301 {
302 	return set_pte_bit(pte, __pgprot(PTE_AF));
303 }
304 
305 static inline pte_t pte_mkspecial(pte_t pte)
306 {
307 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
308 }
309 
310 static inline pte_t pte_mkcont(pte_t pte)
311 {
312 	return set_pte_bit(pte, __pgprot(PTE_CONT));
313 }
314 
315 static inline pte_t pte_mknoncont(pte_t pte)
316 {
317 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
318 }
319 
320 static inline pte_t pte_mkvalid_k(pte_t pte)
321 {
322 	pte = clear_pte_bit(pte, __pgprot(PTE_PRESENT_INVALID));
323 	pte = set_pte_bit(pte, __pgprot(PTE_PRESENT_VALID_KERNEL));
324 	return pte;
325 }
326 
327 static inline pte_t pte_mkinvalid(pte_t pte)
328 {
329 	pte = set_pte_bit(pte, __pgprot(PTE_PRESENT_INVALID));
330 	pte = clear_pte_bit(pte, __pgprot(PTE_VALID));
331 	return pte;
332 }
333 
334 static inline pmd_t pmd_mkcont(pmd_t pmd)
335 {
336 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
337 }
338 
339 static inline pmd_t pmd_mknoncont(pmd_t pmd)
340 {
341 	return __pmd(pmd_val(pmd) & ~PMD_SECT_CONT);
342 }
343 
344 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
345 static inline int pte_uffd(pte_t pte)
346 {
347 	return !!(pte_val(pte) & PTE_UFFD);
348 }
349 
350 static inline pte_t pte_mkuffd(pte_t pte)
351 {
352 	return pte_wrprotect(set_pte_bit(pte, __pgprot(PTE_UFFD)));
353 }
354 
355 static inline pte_t pte_clear_uffd(pte_t pte)
356 {
357 	return clear_pte_bit(pte, __pgprot(PTE_UFFD));
358 }
359 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
360 
361 static inline void __set_pte_nosync(pte_t *ptep, pte_t pte)
362 {
363 	WRITE_ONCE(*ptep, pte);
364 }
365 
366 static inline void __set_pte_complete(pte_t pte)
367 {
368 	/*
369 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
370 	 * has the necessary barriers.
371 	 */
372 	if (pte_valid_not_user(pte))
373 		queue_pte_barriers();
374 }
375 
376 static inline void __set_pte(pte_t *ptep, pte_t pte)
377 {
378 	__set_pte_nosync(ptep, pte);
379 	__set_pte_complete(pte);
380 }
381 
382 static inline pte_t __ptep_get(pte_t *ptep)
383 {
384 	return READ_ONCE(*ptep);
385 }
386 
387 extern void __sync_icache_dcache(pte_t pteval);
388 bool pgattr_change_is_safe(pteval_t old, pteval_t new);
389 
390 #ifdef CONFIG_DEBUG_VM
391 void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep, pte_t pte);
392 #else
393 static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep, pte_t pte)
394 {
395 }
396 #endif /* CONFIG_DEBUG_VM */
397 
398 static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages)
399 {
400 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
401 		__sync_icache_dcache(pte);
402 
403 	/*
404 	 * If the PTE would provide user space access to the tags associated
405 	 * with it then ensure that the MTE tags are synchronised.  Although
406 	 * pte_access_permitted_no_overlay() returns false for exec only
407 	 * mappings, they don't expose tags (instruction fetches don't check
408 	 * tags).
409 	 */
410 	if (system_supports_mte() && pte_access_permitted_no_overlay(pte, false) &&
411 	    !pte_special(pte) && pte_tagged(pte))
412 		mte_sync_tags(pte, nr_pages);
413 }
414 
415 /*
416  * Select all bits except the pfn
417  */
418 #define pte_pgprot pte_pgprot
419 static inline pgprot_t pte_pgprot(pte_t pte)
420 {
421 	unsigned long pfn = pte_pfn(pte);
422 
423 	return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
424 }
425 
426 #define pte_advance_pfn pte_advance_pfn
427 static inline pte_t pte_advance_pfn(pte_t pte, unsigned long nr)
428 {
429 	return pfn_pte(pte_pfn(pte) + nr, pte_pgprot(pte));
430 }
431 
432 /*
433  * Hugetlb definitions.
434  */
435 #define HUGE_MAX_HSTATE		4
436 #define HPAGE_SHIFT		PMD_SHIFT
437 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
438 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
439 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
440 
441 static inline pte_t pgd_pte(pgd_t pgd)
442 {
443 	return __pte(pgd_val(pgd));
444 }
445 
446 static inline pte_t p4d_pte(p4d_t p4d)
447 {
448 	return __pte(p4d_val(p4d));
449 }
450 
451 static inline pte_t pud_pte(pud_t pud)
452 {
453 	return __pte(pud_val(pud));
454 }
455 
456 static inline pud_t pte_pud(pte_t pte)
457 {
458 	return __pud(pte_val(pte));
459 }
460 
461 static inline pmd_t pud_pmd(pud_t pud)
462 {
463 	return __pmd(pud_val(pud));
464 }
465 
466 static inline pte_t pmd_pte(pmd_t pmd)
467 {
468 	return __pte(pmd_val(pmd));
469 }
470 
471 static inline pmd_t pte_pmd(pte_t pte)
472 {
473 	return __pmd(pte_val(pte));
474 }
475 
476 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
477 {
478 	return __pgprot((pgprot_val(prot) & ~PUD_TYPE_MASK) | PUD_TYPE_SECT);
479 }
480 
481 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
482 {
483 	return __pgprot((pgprot_val(prot) & ~PMD_TYPE_MASK) | PMD_TYPE_SECT);
484 }
485 
486 static inline pte_t pte_swp_mkexclusive(pte_t pte)
487 {
488 	return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
489 }
490 
491 static inline bool pte_swp_exclusive(pte_t pte)
492 {
493 	return pte_val(pte) & PTE_SWP_EXCLUSIVE;
494 }
495 
496 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
497 {
498 	return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
499 }
500 
501 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
502 static inline pte_t pte_swp_mkuffd(pte_t pte)
503 {
504 	return set_pte_bit(pte, __pgprot(PTE_SWP_UFFD));
505 }
506 
507 static inline int pte_swp_uffd(pte_t pte)
508 {
509 	return !!(pte_val(pte) & PTE_SWP_UFFD);
510 }
511 
512 static inline pte_t pte_swp_clear_uffd(pte_t pte)
513 {
514 	return clear_pte_bit(pte, __pgprot(PTE_SWP_UFFD));
515 }
516 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
517 
518 #ifdef CONFIG_ARCH_HAS_PTE_PROTNONE
519 static inline int pte_protnone(pte_t pte)
520 {
521 	/*
522 	 * pte_present_invalid() tells us that the pte is invalid from HW
523 	 * perspective but present from SW perspective, so the fields are to be
524 	 * interpreted as per the HW layout. The second 2 checks are the unique
525 	 * encoding that we use for PROT_NONE. It is insufficient to only use
526 	 * the first check because we share the same encoding scheme with pmds
527 	 * which support pmd_mkinvalid(), so can be present-invalid without
528 	 * being PROT_NONE.
529 	 */
530 	return pte_present_invalid(pte) && !pte_user(pte) && !pte_user_exec(pte);
531 }
532 
533 static inline int pmd_protnone(pmd_t pmd)
534 {
535 	return pte_protnone(pmd_pte(pmd));
536 }
537 #endif /* CONFIG_ARCH_HAS_PTE_PROTNONE */
538 
539 #define pmd_present(pmd)	pte_present(pmd_pte(pmd))
540 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
541 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
542 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
543 #define pmd_user(pmd)		pte_user(pmd_pte(pmd))
544 #define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
545 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
546 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
547 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
548 #define pmd_mkwrite_novma(pmd)	pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)))
549 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
550 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
551 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
552 #define pmd_mkvalid_k(pmd)	pte_pmd(pte_mkvalid_k(pmd_pte(pmd)))
553 #define pmd_mkinvalid(pmd)	pte_pmd(pte_mkinvalid(pmd_pte(pmd)))
554 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
555 #define pmd_uffd(pmd)	pte_uffd(pmd_pte(pmd))
556 #define pmd_mkuffd(pmd)	pte_pmd(pte_mkuffd(pmd_pte(pmd)))
557 #define pmd_clear_uffd(pmd)	pte_pmd(pte_clear_uffd(pmd_pte(pmd)))
558 #define pmd_swp_uffd(pmd)	pte_swp_uffd(pmd_pte(pmd))
559 #define pmd_swp_mkuffd(pmd)	pte_pmd(pte_swp_mkuffd(pmd_pte(pmd)))
560 #define pmd_swp_clear_uffd(pmd) \
561 				pte_pmd(pte_swp_clear_uffd(pmd_pte(pmd)))
562 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
563 
564 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
565 
566 static inline pmd_t pmd_mkhuge(pmd_t pmd)
567 {
568 	/*
569 	 * It's possible that the pmd is present-invalid on entry
570 	 * and in that case it needs to remain present-invalid on
571 	 * exit. So ensure the VALID bit does not get modified.
572 	 */
573 	pmdval_t mask = PMD_TYPE_MASK & ~PTE_VALID;
574 	pmdval_t val = PMD_TYPE_SECT & ~PTE_VALID;
575 
576 	return __pmd((pmd_val(pmd) & ~mask) | val);
577 }
578 
579 #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP
580 #define pmd_special(pte)	(!!((pmd_val(pte) & PTE_SPECIAL)))
581 static inline pmd_t pmd_mkspecial(pmd_t pmd)
582 {
583 	return set_pmd_bit(pmd, __pgprot(PTE_SPECIAL));
584 }
585 #endif
586 
587 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
588 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
589 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
590 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
591 
592 #define pud_young(pud)		pte_young(pud_pte(pud))
593 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
594 #define pud_mkwrite_novma(pud)	pte_pud(pte_mkwrite_novma(pud_pte(pud)))
595 #define pud_mkvalid_k(pud)	pte_pud(pte_mkvalid_k(pud_pte(pud)))
596 #define pud_write(pud)		pte_write(pud_pte(pud))
597 
598 static inline pud_t pud_mkhuge(pud_t pud)
599 {
600 	/*
601 	 * It's possible that the pud is present-invalid on entry
602 	 * and in that case it needs to remain present-invalid on
603 	 * exit. So ensure the VALID bit does not get modified.
604 	 */
605 	pudval_t mask = PUD_TYPE_MASK & ~PTE_VALID;
606 	pudval_t val = PUD_TYPE_SECT & ~PTE_VALID;
607 
608 	return __pud((pud_val(pud) & ~mask) | val);
609 }
610 
611 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
612 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
613 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
614 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
615 
616 #define pmd_pgprot pmd_pgprot
617 static inline pgprot_t pmd_pgprot(pmd_t pmd)
618 {
619 	unsigned long pfn = pmd_pfn(pmd);
620 
621 	return __pgprot(pmd_val(pfn_pmd(pfn, __pgprot(0))) ^ pmd_val(pmd));
622 }
623 
624 #define pud_pgprot pud_pgprot
625 static inline pgprot_t pud_pgprot(pud_t pud)
626 {
627 	unsigned long pfn = pud_pfn(pud);
628 
629 	return __pgprot(pud_val(pfn_pud(pfn, __pgprot(0))) ^ pud_val(pud));
630 }
631 
632 static inline void __set_ptes_anysz(struct mm_struct *mm, unsigned long addr,
633 				    pte_t *ptep, pte_t pte, unsigned int nr,
634 				    unsigned long pgsize)
635 {
636 	unsigned long stride = pgsize >> PAGE_SHIFT;
637 
638 	switch (pgsize) {
639 	case PAGE_SIZE:
640 		page_table_check_ptes_set(mm, addr, ptep, pte, nr);
641 		break;
642 	case PMD_SIZE:
643 		page_table_check_pmds_set(mm, addr, (pmd_t *)ptep,
644 					  pte_pmd(pte), nr);
645 		break;
646 #ifndef __PAGETABLE_PMD_FOLDED
647 	case PUD_SIZE:
648 		page_table_check_puds_set(mm, addr, (pud_t *)ptep,
649 					  pte_pud(pte), nr);
650 		break;
651 #endif
652 	default:
653 		VM_WARN_ON(1);
654 	}
655 
656 	__sync_cache_and_tags(pte, nr * stride);
657 
658 	for (;;) {
659 		__check_safe_pte_update(mm, ptep, pte);
660 		__set_pte_nosync(ptep, pte);
661 		if (--nr == 0)
662 			break;
663 		ptep++;
664 		pte = pte_advance_pfn(pte, stride);
665 	}
666 
667 	__set_pte_complete(pte);
668 }
669 
670 static inline void __set_ptes(struct mm_struct *mm, unsigned long addr,
671 			      pte_t *ptep, pte_t pte, unsigned int nr)
672 {
673 	__set_ptes_anysz(mm, addr, ptep, pte, nr, PAGE_SIZE);
674 }
675 
676 static inline void __set_pmds(struct mm_struct *mm, unsigned long addr,
677 			      pmd_t *pmdp, pmd_t pmd, unsigned int nr)
678 {
679 	__set_ptes_anysz(mm, addr, (pte_t *)pmdp, pmd_pte(pmd), nr, PMD_SIZE);
680 }
681 #define set_pmd_at(mm, addr, pmdp, pmd) __set_pmds(mm, addr, pmdp, pmd, 1)
682 
683 static inline void __set_puds(struct mm_struct *mm, unsigned long addr,
684 			      pud_t *pudp, pud_t pud, unsigned int nr)
685 {
686 	__set_ptes_anysz(mm, addr, (pte_t *)pudp, pud_pte(pud), nr, PUD_SIZE);
687 }
688 #define set_pud_at(mm, addr, pudp, pud) __set_puds(mm, addr, pudp, pud, 1)
689 
690 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
691 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
692 
693 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
694 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
695 
696 #define __pgprot_modify(prot,mask,bits) \
697 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
698 
699 #define pgprot_nx(prot) \
700 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
701 
702 #define pgprot_decrypted(prot) \
703 	__pgprot_modify(prot, PROT_NS_SHARED, PROT_NS_SHARED)
704 #define pgprot_encrypted(prot) \
705 	__pgprot_modify(prot, PROT_NS_SHARED, 0)
706 
707 /*
708  * Mark the prot value as uncacheable and unbufferable.
709  */
710 #define pgprot_noncached(prot) \
711 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
712 #define pgprot_writecombine(prot) \
713 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
714 #define pgprot_device(prot) \
715 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
716 #define pgprot_tagged(prot) \
717 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
718 #define pgprot_mhp	pgprot_tagged
719 /*
720  * DMA allocations for non-coherent devices use what the Arm architecture calls
721  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
722  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
723  * is intended for MMIO and thus forbids speculation, preserves access size,
724  * requires strict alignment and can also force write responses to come from the
725  * endpoint.
726  */
727 #define pgprot_dmacoherent(prot) \
728 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
729 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
730 
731 #define __HAVE_PHYS_MEM_ACCESS_PROT
732 struct file;
733 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
734 				     unsigned long size, pgprot_t vma_prot);
735 
736 #define pmd_none(pmd)		(!pmd_val(pmd))
737 
738 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
739 				 PMD_TYPE_TABLE)
740 
741 #define pmd_leaf pmd_leaf
742 static inline bool pmd_leaf(pmd_t pmd)
743 {
744 	return pmd_present(pmd) && !pmd_table(pmd);
745 }
746 
747 #define pmd_bad(pmd)		(!pmd_table(pmd))
748 
749 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
750 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
751 
752 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
753 static inline int pmd_trans_huge(pmd_t pmd)
754 {
755 	/*
756 	 * If pmd is present-invalid, pmd_table() won't detect it
757 	 * as a table, so force the valid bit for the comparison.
758 	 */
759 	return pmd_present(pmd) && !pmd_table(__pmd(pmd_val(pmd) | PTE_VALID));
760 }
761 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
762 
763 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
764 static inline bool pud_table(pud_t pud) { return true; }
765 #else
766 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
767 				 PUD_TYPE_TABLE)
768 #endif
769 
770 extern pgd_t swapper_pg_dir[];
771 extern pgd_t idmap_pg_dir[];
772 extern pgd_t tramp_pg_dir[];
773 extern pgd_t reserved_pg_dir[];
774 
775 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
776 
777 static inline bool in_swapper_pgdir(void *addr)
778 {
779 	return ((unsigned long)addr & PAGE_MASK) ==
780 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
781 }
782 
783 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
784 {
785 #ifdef __PAGETABLE_PMD_FOLDED
786 	if (in_swapper_pgdir(pmdp)) {
787 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
788 		return;
789 	}
790 #endif /* __PAGETABLE_PMD_FOLDED */
791 
792 	WRITE_ONCE(*pmdp, pmd);
793 
794 	if (pmd_valid(pmd))
795 		queue_pte_barriers();
796 }
797 
798 static inline void pmd_clear(pmd_t *pmdp)
799 {
800 	set_pmd(pmdp, __pmd(0));
801 }
802 
803 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
804 {
805 	return __pmd_to_phys(pmd);
806 }
807 
808 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
809 {
810 	return (unsigned long)__va(pmd_page_paddr(pmd));
811 }
812 
813 /* Find an entry in the third-level page table. */
814 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
815 
816 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
817 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
818 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
819 
820 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
821 
822 /* use ONLY for statically allocated translation tables */
823 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
824 
825 #if CONFIG_PGTABLE_LEVELS > 2
826 
827 #define pud_none(pud)		(!pud_val(pud))
828 #define pud_bad(pud)		((pud_val(pud) & PUD_TYPE_MASK) != \
829 				 PUD_TYPE_TABLE)
830 #define pud_present(pud)	pte_present(pud_pte(pud))
831 #ifndef __PAGETABLE_PMD_FOLDED
832 #define pud_leaf pud_leaf
833 static inline bool pud_leaf(pud_t pud)
834 {
835 	return pud_present(pud) && !pud_table(pud);
836 }
837 #else
838 #define pud_leaf(pud)		false
839 #endif
840 #define pud_valid(pud)		pte_valid(pud_pte(pud))
841 #define pud_user(pud)		pte_user(pud_pte(pud))
842 #define pud_user_exec(pud)	pte_user_exec(pud_pte(pud))
843 
844 static inline bool pgtable_l4_enabled(void);
845 
846 static inline void set_pud(pud_t *pudp, pud_t pud)
847 {
848 	if (!pgtable_l4_enabled() && in_swapper_pgdir(pudp)) {
849 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
850 		return;
851 	}
852 
853 	WRITE_ONCE(*pudp, pud);
854 
855 	if (pud_valid(pud))
856 		queue_pte_barriers();
857 }
858 
859 static inline void pud_clear(pud_t *pudp)
860 {
861 	set_pud(pudp, __pud(0));
862 }
863 
864 static inline phys_addr_t pud_page_paddr(pud_t pud)
865 {
866 	return __pud_to_phys(pud);
867 }
868 
869 static inline pmd_t *pud_pgtable(pud_t pud)
870 {
871 	return (pmd_t *)__va(pud_page_paddr(pud));
872 }
873 
874 /* Find an entry in the second-level page table. */
875 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
876 
877 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
878 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
879 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
880 
881 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
882 
883 /* use ONLY for statically allocated translation tables */
884 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
885 
886 #else
887 
888 #define pud_valid(pud)		false
889 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
890 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
891 
892 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
893 #define pmd_set_fixmap(addr)		NULL
894 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
895 #define pmd_clear_fixmap()
896 
897 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
898 
899 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
900 
901 #if CONFIG_PGTABLE_LEVELS > 3
902 
903 static __always_inline bool pgtable_l4_enabled(void)
904 {
905 	if (CONFIG_PGTABLE_LEVELS > 4 || !IS_ENABLED(CONFIG_ARM64_LPA2))
906 		return true;
907 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
908 		return vabits_actual == VA_BITS;
909 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
910 }
911 
912 static inline bool mm_pud_folded(const struct mm_struct *mm)
913 {
914 	return !pgtable_l4_enabled();
915 }
916 #define mm_pud_folded  mm_pud_folded
917 
918 #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
919 #define p4d_bad(p4d)		(pgtable_l4_enabled() && \
920 				((p4d_val(p4d) & P4D_TYPE_MASK) != \
921 				 P4D_TYPE_TABLE))
922 #define p4d_present(p4d)	(!p4d_none(p4d))
923 
924 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
925 {
926 	if (in_swapper_pgdir(p4dp)) {
927 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
928 		return;
929 	}
930 
931 	WRITE_ONCE(*p4dp, p4d);
932 	queue_pte_barriers();
933 }
934 
935 static inline void p4d_clear(p4d_t *p4dp)
936 {
937 	if (pgtable_l4_enabled())
938 		set_p4d(p4dp, __p4d(0));
939 }
940 
941 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
942 {
943 	return __p4d_to_phys(p4d);
944 }
945 
946 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
947 
948 static inline pud_t *p4d_to_folded_pud(p4d_t *p4dp, unsigned long addr)
949 {
950 	/* Ensure that 'p4dp' indexes a page table according to 'addr' */
951 	VM_BUG_ON(((addr >> P4D_SHIFT) ^ ((u64)p4dp >> 3)) % PTRS_PER_P4D);
952 
953 	return (pud_t *)PTR_ALIGN_DOWN(p4dp, PAGE_SIZE) + pud_index(addr);
954 }
955 
956 static inline pud_t *p4d_pgtable(p4d_t p4d)
957 {
958 	return (pud_t *)__va(p4d_page_paddr(p4d));
959 }
960 
961 static inline phys_addr_t pud_offset_phys(p4d_t *p4dp, unsigned long addr)
962 {
963 	VM_WARN_ON_ONCE(!pgtable_l4_enabled());
964 
965 	return p4d_page_paddr(READ_ONCE(*p4dp)) + pud_index(addr) * sizeof(pud_t);
966 }
967 
968 static inline
969 pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long addr)
970 {
971 	if (!pgtable_l4_enabled())
972 		return p4d_to_folded_pud(p4dp, addr);
973 	return (pud_t *)__va(p4d_page_paddr(p4d)) + pud_index(addr);
974 }
975 #define pud_offset_lockless pud_offset_lockless
976 
977 static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long addr)
978 {
979 	return pud_offset_lockless(p4dp, READ_ONCE(*p4dp), addr);
980 }
981 #define pud_offset	pud_offset
982 
983 static inline pud_t *pud_set_fixmap(unsigned long addr)
984 {
985 	if (!pgtable_l4_enabled())
986 		return NULL;
987 	return (pud_t *)set_fixmap_offset(FIX_PUD, addr);
988 }
989 
990 static inline pud_t *pud_set_fixmap_offset(p4d_t *p4dp, unsigned long addr)
991 {
992 	if (!pgtable_l4_enabled())
993 		return p4d_to_folded_pud(p4dp, addr);
994 	return pud_set_fixmap(pud_offset_phys(p4dp, addr));
995 }
996 
997 static inline void pud_clear_fixmap(void)
998 {
999 	if (pgtable_l4_enabled())
1000 		clear_fixmap(FIX_PUD);
1001 }
1002 
1003 /* use ONLY for statically allocated translation tables */
1004 static inline pud_t *pud_offset_kimg(p4d_t *p4dp, u64 addr)
1005 {
1006 	if (!pgtable_l4_enabled())
1007 		return p4d_to_folded_pud(p4dp, addr);
1008 	return (pud_t *)__phys_to_kimg(pud_offset_phys(p4dp, addr));
1009 }
1010 
1011 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
1012 
1013 #else
1014 
1015 static inline bool pgtable_l4_enabled(void) { return false; }
1016 
1017 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
1018 
1019 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
1020 #define pud_set_fixmap(addr)		NULL
1021 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
1022 #define pud_clear_fixmap()
1023 
1024 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
1025 
1026 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
1027 
1028 #if CONFIG_PGTABLE_LEVELS > 4
1029 
1030 static __always_inline bool pgtable_l5_enabled(void)
1031 {
1032 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
1033 		return vabits_actual == VA_BITS;
1034 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
1035 }
1036 
1037 static inline bool mm_p4d_folded(const struct mm_struct *mm)
1038 {
1039 	return !pgtable_l5_enabled();
1040 }
1041 #define mm_p4d_folded  mm_p4d_folded
1042 
1043 #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
1044 #define pgd_bad(pgd)		(pgtable_l5_enabled() && \
1045 				((pgd_val(pgd) & PGD_TYPE_MASK) != \
1046 				 PGD_TYPE_TABLE))
1047 #define pgd_present(pgd)	(!pgd_none(pgd))
1048 
1049 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
1050 {
1051 	if (in_swapper_pgdir(pgdp)) {
1052 		set_swapper_pgd(pgdp, __pgd(pgd_val(pgd)));
1053 		return;
1054 	}
1055 
1056 	WRITE_ONCE(*pgdp, pgd);
1057 	queue_pte_barriers();
1058 }
1059 
1060 static inline void pgd_clear(pgd_t *pgdp)
1061 {
1062 	if (pgtable_l5_enabled())
1063 		set_pgd(pgdp, __pgd(0));
1064 }
1065 
1066 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
1067 {
1068 	return __pgd_to_phys(pgd);
1069 }
1070 
1071 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1072 
1073 static inline p4d_t *pgd_to_folded_p4d(pgd_t *pgdp, unsigned long addr)
1074 {
1075 	/* Ensure that 'pgdp' indexes a page table according to 'addr' */
1076 	VM_BUG_ON(((addr >> PGDIR_SHIFT) ^ ((u64)pgdp >> 3)) % PTRS_PER_PGD);
1077 
1078 	return (p4d_t *)PTR_ALIGN_DOWN(pgdp, PAGE_SIZE) + p4d_index(addr);
1079 }
1080 
1081 static inline phys_addr_t p4d_offset_phys(pgd_t *pgdp, unsigned long addr)
1082 {
1083 	VM_WARN_ON_ONCE(!pgtable_l5_enabled());
1084 
1085 	return pgd_page_paddr(READ_ONCE(*pgdp)) + p4d_index(addr) * sizeof(p4d_t);
1086 }
1087 
1088 static inline
1089 p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1090 {
1091 	if (!pgtable_l5_enabled())
1092 		return pgd_to_folded_p4d(pgdp, addr);
1093 	return (p4d_t *)__va(pgd_page_paddr(pgd)) + p4d_index(addr);
1094 }
1095 #define p4d_offset_lockless p4d_offset_lockless
1096 
1097 static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long addr)
1098 {
1099 	return p4d_offset_lockless(pgdp, READ_ONCE(*pgdp), addr);
1100 }
1101 
1102 static inline p4d_t *p4d_set_fixmap(unsigned long addr)
1103 {
1104 	if (!pgtable_l5_enabled())
1105 		return NULL;
1106 	return (p4d_t *)set_fixmap_offset(FIX_P4D, addr);
1107 }
1108 
1109 static inline p4d_t *p4d_set_fixmap_offset(pgd_t *pgdp, unsigned long addr)
1110 {
1111 	if (!pgtable_l5_enabled())
1112 		return pgd_to_folded_p4d(pgdp, addr);
1113 	return p4d_set_fixmap(p4d_offset_phys(pgdp, addr));
1114 }
1115 
1116 static inline void p4d_clear_fixmap(void)
1117 {
1118 	if (pgtable_l5_enabled())
1119 		clear_fixmap(FIX_P4D);
1120 }
1121 
1122 /* use ONLY for statically allocated translation tables */
1123 static inline p4d_t *p4d_offset_kimg(pgd_t *pgdp, u64 addr)
1124 {
1125 	if (!pgtable_l5_enabled())
1126 		return pgd_to_folded_p4d(pgdp, addr);
1127 	return (p4d_t *)__phys_to_kimg(p4d_offset_phys(pgdp, addr));
1128 }
1129 
1130 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
1131 
1132 #else
1133 
1134 static inline bool pgtable_l5_enabled(void) { return false; }
1135 
1136 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1137 
1138 /* Match p4d_offset folding in <asm/generic/pgtable-nop4d.h> */
1139 #define p4d_set_fixmap(addr)		NULL
1140 #define p4d_set_fixmap_offset(p4dp, addr)	((p4d_t *)p4dp)
1141 #define p4d_clear_fixmap()
1142 
1143 #define p4d_offset_kimg(dir,addr)	((p4d_t *)dir)
1144 
1145 static inline
1146 p4d_t *p4d_offset_lockless_folded(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1147 {
1148 	/*
1149 	 * With runtime folding of the pud, pud_offset_lockless() passes
1150 	 * the 'pgd_t *' we return here to p4d_to_folded_pud(), which
1151 	 * will offset the pointer assuming that it points into
1152 	 * a page-table page. However, the fast GUP path passes us a
1153 	 * pgd_t allocated on the stack and so we must use the original
1154 	 * pointer in 'pgdp' to construct the p4d pointer instead of
1155 	 * using the generic p4d_offset_lockless() implementation.
1156 	 *
1157 	 * Note: reusing the original pointer means that we may
1158 	 * dereference the same (live) page-table entry multiple times.
1159 	 * This is safe because it is still only loaded once in the
1160 	 * context of each level and the CPU guarantees same-address
1161 	 * read-after-read ordering.
1162 	 */
1163 	return p4d_offset(pgdp, addr);
1164 }
1165 #define p4d_offset_lockless p4d_offset_lockless_folded
1166 
1167 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
1168 
1169 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
1170 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
1171 
1172 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
1173 {
1174 	/*
1175 	 * Normal and Normal-Tagged are two different memory types and indices
1176 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
1177 	 */
1178 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
1179 			      PTE_PRESENT_INVALID | PTE_VALID | PTE_WRITE |
1180 			      PTE_GP | PTE_ATTRINDX_MASK | PTE_PO_IDX_MASK;
1181 
1182 	/* preserve the hardware dirty information */
1183 	if (pte_hw_dirty(pte))
1184 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
1185 
1186 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
1187 	/*
1188 	 * If we end up clearing hw dirtiness for a sw-dirty PTE, set hardware
1189 	 * dirtiness again.
1190 	 */
1191 	if (pte_sw_dirty(pte))
1192 		pte = pte_mkdirty(pte);
1193 	return pte;
1194 }
1195 
1196 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1197 {
1198 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
1199 }
1200 
1201 extern int __ptep_set_access_flags_anysz(struct vm_area_struct *vma,
1202 					 unsigned long address, pte_t *ptep,
1203 					 pte_t entry, int dirty,
1204 					 unsigned long pgsize);
1205 
1206 static inline int __ptep_set_access_flags(struct vm_area_struct *vma,
1207 					  unsigned long address, pte_t *ptep,
1208 					  pte_t entry, int dirty)
1209 {
1210 	return __ptep_set_access_flags_anysz(vma, address, ptep, entry, dirty,
1211 					     PAGE_SIZE);
1212 }
1213 
1214 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1215 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1216 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1217 					unsigned long address, pmd_t *pmdp,
1218 					pmd_t entry, int dirty)
1219 {
1220 	return __ptep_set_access_flags_anysz(vma, address, (pte_t *)pmdp,
1221 					     pmd_pte(entry), dirty, PMD_SIZE);
1222 }
1223 #endif
1224 
1225 #ifdef CONFIG_PAGE_TABLE_CHECK
1226 static inline bool pte_user_accessible_page(struct mm_struct *mm, unsigned long addr, pte_t pte)
1227 {
1228 	return pte_valid(pte) && (pte_user(pte) || pte_user_exec(pte));
1229 }
1230 
1231 static inline bool pmd_user_accessible_page(struct mm_struct *mm, unsigned long addr, pmd_t pmd)
1232 {
1233 	return pmd_valid(pmd) && !pmd_table(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
1234 }
1235 
1236 static inline bool pud_user_accessible_page(struct mm_struct *mm, unsigned long addr, pud_t pud)
1237 {
1238 	return pud_valid(pud) && !pud_table(pud) && (pud_user(pud) || pud_user_exec(pud));
1239 }
1240 #endif
1241 
1242 /*
1243  * Atomic pte/pmd modifications.
1244  */
1245 
1246 static inline void __pte_clear(struct mm_struct *mm,
1247 			       unsigned long addr, pte_t *ptep)
1248 {
1249 	__set_pte(ptep, __pte(0));
1250 }
1251 
1252 static inline bool __ptep_test_and_clear_young(struct vm_area_struct *vma,
1253 		unsigned long address, pte_t *ptep)
1254 {
1255 	pte_t old_pte, pte;
1256 
1257 	pte = __ptep_get(ptep);
1258 	do {
1259 		old_pte = pte;
1260 		pte = pte_mkold(pte);
1261 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1262 					       pte_val(old_pte), pte_val(pte));
1263 	} while (pte_val(pte) != pte_val(old_pte));
1264 
1265 	return pte_young(pte);
1266 }
1267 
1268 static inline bool __ptep_clear_flush_young(struct vm_area_struct *vma,
1269 		unsigned long address, pte_t *ptep)
1270 {
1271 	bool young = __ptep_test_and_clear_young(vma, address, ptep);
1272 
1273 	if (young) {
1274 		/*
1275 		 * We can elide the trailing DSB here since the worst that can
1276 		 * happen is that a CPU continues to use the young entry in its
1277 		 * TLB and we mistakenly reclaim the associated page. The
1278 		 * window for such an event is bounded by the next
1279 		 * context-switch, which provides a DSB to complete the TLB
1280 		 * invalidation.
1281 		 */
1282 		__flush_tlb_page(vma, address, TLBF_NOSYNC);
1283 	}
1284 
1285 	return young;
1286 }
1287 
1288 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
1289 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1290 static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
1291 		unsigned long address, pmd_t *pmdp)
1292 {
1293 	/* Operation applies to PMD table entry only if FEAT_HAFT is enabled */
1294 	VM_WARN_ON(pmd_table(READ_ONCE(*pmdp)) && !system_supports_haft());
1295 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
1296 }
1297 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */
1298 
1299 static inline pte_t __ptep_get_and_clear_anysz(struct mm_struct *mm,
1300 					       unsigned long address,
1301 					       pte_t *ptep,
1302 					       unsigned long pgsize)
1303 {
1304 	pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
1305 
1306 	switch (pgsize) {
1307 	case PAGE_SIZE:
1308 		page_table_check_pte_clear(mm, address, pte);
1309 		break;
1310 	case PMD_SIZE:
1311 		page_table_check_pmd_clear(mm, address, pte_pmd(pte));
1312 		break;
1313 #ifndef __PAGETABLE_PMD_FOLDED
1314 	case PUD_SIZE:
1315 		page_table_check_pud_clear(mm, address, pte_pud(pte));
1316 		break;
1317 #endif
1318 	default:
1319 		VM_WARN_ON(1);
1320 	}
1321 
1322 	return pte;
1323 }
1324 
1325 static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
1326 				       unsigned long address, pte_t *ptep)
1327 {
1328 	return __ptep_get_and_clear_anysz(mm, address, ptep, PAGE_SIZE);
1329 }
1330 
1331 static inline void __clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1332 				pte_t *ptep, unsigned int nr, int full)
1333 {
1334 	for (;;) {
1335 		__ptep_get_and_clear(mm, addr, ptep);
1336 		if (--nr == 0)
1337 			break;
1338 		ptep++;
1339 		addr += PAGE_SIZE;
1340 	}
1341 }
1342 
1343 static inline pte_t __get_and_clear_full_ptes(struct mm_struct *mm,
1344 				unsigned long addr, pte_t *ptep,
1345 				unsigned int nr, int full)
1346 {
1347 	pte_t pte, tmp_pte;
1348 
1349 	pte = __ptep_get_and_clear(mm, addr, ptep);
1350 	while (--nr) {
1351 		ptep++;
1352 		addr += PAGE_SIZE;
1353 		tmp_pte = __ptep_get_and_clear(mm, addr, ptep);
1354 		if (pte_dirty(tmp_pte))
1355 			pte = pte_mkdirty(pte);
1356 		if (pte_young(tmp_pte))
1357 			pte = pte_mkyoung(pte);
1358 	}
1359 	return pte;
1360 }
1361 
1362 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1363 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1364 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1365 					    unsigned long address, pmd_t *pmdp)
1366 {
1367 	return pte_pmd(__ptep_get_and_clear_anysz(mm, address, (pte_t *)pmdp, PMD_SIZE));
1368 }
1369 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1370 
1371 static inline void ___ptep_set_wrprotect(struct mm_struct *mm,
1372 					unsigned long address, pte_t *ptep,
1373 					pte_t pte)
1374 {
1375 	pte_t old_pte;
1376 
1377 	do {
1378 		old_pte = pte;
1379 		pte = pte_wrprotect(pte);
1380 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1381 					       pte_val(old_pte), pte_val(pte));
1382 	} while (pte_val(pte) != pte_val(old_pte));
1383 }
1384 
1385 /*
1386  * __ptep_set_wrprotect - mark read-only while transferring potential hardware
1387  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
1388  */
1389 static inline void __ptep_set_wrprotect(struct mm_struct *mm,
1390 					unsigned long address, pte_t *ptep)
1391 {
1392 	___ptep_set_wrprotect(mm, address, ptep, __ptep_get(ptep));
1393 }
1394 
1395 static inline void __wrprotect_ptes(struct mm_struct *mm, unsigned long address,
1396 				pte_t *ptep, unsigned int nr)
1397 {
1398 	unsigned int i;
1399 
1400 	for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++)
1401 		__ptep_set_wrprotect(mm, address, ptep);
1402 }
1403 
1404 static inline void __clear_young_dirty_pte(struct vm_area_struct *vma,
1405 					   unsigned long addr, pte_t *ptep,
1406 					   pte_t pte, cydp_t flags)
1407 {
1408 	pte_t old_pte;
1409 
1410 	do {
1411 		old_pte = pte;
1412 
1413 		if (flags & CYDP_CLEAR_YOUNG)
1414 			pte = pte_mkold(pte);
1415 		if (flags & CYDP_CLEAR_DIRTY)
1416 			pte = pte_mkclean(pte);
1417 
1418 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1419 					       pte_val(old_pte), pte_val(pte));
1420 	} while (pte_val(pte) != pte_val(old_pte));
1421 }
1422 
1423 static inline void __clear_young_dirty_ptes(struct vm_area_struct *vma,
1424 					    unsigned long addr, pte_t *ptep,
1425 					    unsigned int nr, cydp_t flags)
1426 {
1427 	pte_t pte;
1428 
1429 	for (;;) {
1430 		pte = __ptep_get(ptep);
1431 
1432 		if (flags == (CYDP_CLEAR_YOUNG | CYDP_CLEAR_DIRTY))
1433 			__set_pte(ptep, pte_mkclean(pte_mkold(pte)));
1434 		else
1435 			__clear_young_dirty_pte(vma, addr, ptep, pte, flags);
1436 
1437 		if (--nr == 0)
1438 			break;
1439 		ptep++;
1440 		addr += PAGE_SIZE;
1441 	}
1442 }
1443 
1444 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1445 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1446 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1447 				      unsigned long address, pmd_t *pmdp)
1448 {
1449 	__ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
1450 }
1451 
1452 #define pmdp_establish pmdp_establish
1453 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1454 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1455 {
1456 	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
1457 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
1458 }
1459 #endif
1460 
1461 /*
1462  * Encode and decode a swap entry:
1463  *	bits 0-1:	present (must be zero)
1464  *	bits 2:		remember PG_anon_exclusive
1465  *	bit  3:		remember uffd state
1466  *	bits 6-10:	swap type
1467  *	bit  11:	PTE_PRESENT_INVALID (must be zero)
1468  *	bits 12-61:	swap offset
1469  */
1470 #define __SWP_TYPE_SHIFT	6
1471 #define __SWP_TYPE_BITS		5
1472 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
1473 #define __SWP_OFFSET_SHIFT	12
1474 #define __SWP_OFFSET_BITS	50
1475 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
1476 
1477 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
1478 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
1479 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
1480 
1481 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1482 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
1483 
1484 #ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES
1485 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
1486 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
1487 #endif /* CONFIG_ARCH_HAS_PMD_SOFTLEAVES */
1488 
1489 /*
1490  * Ensure that there are not more swap files than can be encoded in the kernel
1491  * PTEs.
1492  */
1493 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
1494 
1495 #ifdef CONFIG_ARM64_MTE
1496 
1497 #define __HAVE_ARCH_PREPARE_TO_SWAP
1498 extern int arch_prepare_to_swap(struct folio *folio);
1499 
1500 #define __HAVE_ARCH_SWAP_INVALIDATE
1501 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
1502 {
1503 	if (system_supports_mte())
1504 		mte_invalidate_tags(type, offset);
1505 }
1506 
1507 static inline void arch_swap_invalidate_area(int type)
1508 {
1509 	if (system_supports_mte())
1510 		mte_invalidate_tags_area(type);
1511 }
1512 
1513 #define __HAVE_ARCH_SWAP_RESTORE
1514 extern void arch_swap_restore(swp_entry_t entry, struct folio *folio);
1515 
1516 #endif /* CONFIG_ARM64_MTE */
1517 
1518 /*
1519  * On AArch64, the cache coherency is handled via the __set_ptes() function.
1520  */
1521 static inline void update_mmu_cache_range(struct vm_fault *vmf,
1522 		struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
1523 		unsigned int nr)
1524 {
1525 	/*
1526 	 * We don't do anything here, so there's a very small chance of
1527 	 * us retaking a user fault which we just fixed up. The alternative
1528 	 * is doing a dsb(ishst), but that penalises the fastpath.
1529 	 */
1530 }
1531 
1532 #define update_mmu_cache(vma, addr, ptep) \
1533 	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
1534 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
1535 
1536 #ifdef CONFIG_ARM64_PA_BITS_52
1537 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
1538 #else
1539 #define phys_to_ttbr(addr)	(addr)
1540 #endif
1541 
1542 /*
1543  * On arm64 without hardware Access Flag, copying from user will fail because
1544  * the pte is old and cannot be marked young. So we always end up with zeroed
1545  * page after fork() + CoW for pfn mappings. We don't always have a
1546  * hardware-managed access flag on arm64.
1547  */
1548 #define arch_has_hw_pte_young		cpu_has_hw_af
1549 
1550 #ifdef CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG
1551 #define arch_has_hw_nonleaf_pmd_young	system_supports_haft
1552 #endif
1553 
1554 /*
1555  * Experimentally, it's cheap to set the access flag in hardware and we
1556  * benefit from prefaulting mappings as 'old' to start with.
1557  */
1558 #define arch_wants_old_prefaulted_pte	cpu_has_hw_af
1559 
1560 /*
1561  * Request exec memory is read into pagecache in at least 64K folios. This size
1562  * can be contpte-mapped when 4K base pages are in use (16 pages into 1 iTLB
1563  * entry), and HPA can coalesce it (4 pages into 1 TLB entry) when 16K base
1564  * pages are in use.
1565  */
1566 #define exec_folio_order() ilog2(SZ_64K >> PAGE_SHIFT)
1567 
1568 static inline bool pud_sect_supported(void)
1569 {
1570 	return PAGE_SIZE == SZ_4K;
1571 }
1572 
1573 
1574 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
1575 #define ptep_modify_prot_start ptep_modify_prot_start
1576 extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
1577 				    unsigned long addr, pte_t *ptep);
1578 
1579 #define ptep_modify_prot_commit ptep_modify_prot_commit
1580 extern void ptep_modify_prot_commit(struct vm_area_struct *vma,
1581 				    unsigned long addr, pte_t *ptep,
1582 				    pte_t old_pte, pte_t new_pte);
1583 
1584 #define modify_prot_start_ptes modify_prot_start_ptes
1585 extern pte_t modify_prot_start_ptes(struct vm_area_struct *vma,
1586 				    unsigned long addr, pte_t *ptep,
1587 				    unsigned int nr);
1588 
1589 #define modify_prot_commit_ptes modify_prot_commit_ptes
1590 extern void modify_prot_commit_ptes(struct vm_area_struct *vma, unsigned long addr,
1591 				    pte_t *ptep, pte_t old_pte, pte_t pte,
1592 				    unsigned int nr);
1593 
1594 #ifdef CONFIG_ARM64_CONTPTE
1595 
1596 /*
1597  * The contpte APIs are used to transparently manage the contiguous bit in ptes
1598  * where it is possible and makes sense to do so. The PTE_CONT bit is considered
1599  * a private implementation detail of the public ptep API (see below).
1600  */
1601 extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
1602 				pte_t *ptep, pte_t pte);
1603 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
1604 				pte_t *ptep, pte_t pte);
1605 extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
1606 extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
1607 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
1608 				pte_t *ptep, pte_t pte, unsigned int nr);
1609 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1610 				pte_t *ptep, unsigned int nr, int full);
1611 extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
1612 				unsigned long addr, pte_t *ptep,
1613 				unsigned int nr, int full);
1614 bool contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
1615 				unsigned long addr, pte_t *ptep, unsigned int nr);
1616 bool contpte_clear_flush_young_ptes(struct vm_area_struct *vma,
1617 				unsigned long addr, pte_t *ptep, unsigned int nr);
1618 extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
1619 				pte_t *ptep, unsigned int nr);
1620 extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
1621 				unsigned long addr, pte_t *ptep,
1622 				pte_t entry, int dirty);
1623 extern void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
1624 				unsigned long addr, pte_t *ptep,
1625 				unsigned int nr, cydp_t flags);
1626 
1627 static __always_inline void contpte_try_fold(struct mm_struct *mm,
1628 				unsigned long addr, pte_t *ptep, pte_t pte)
1629 {
1630 	/*
1631 	 * Only bother trying if both the virtual and physical addresses are
1632 	 * aligned and correspond to the last entry in a contig range. The core
1633 	 * code mostly modifies ranges from low to high, so this is the likely
1634 	 * the last modification in the contig range, so a good time to fold.
1635 	 * We can't fold special mappings, because there is no associated folio.
1636 	 */
1637 
1638 	const unsigned long contmask = CONT_PTES - 1;
1639 	bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
1640 
1641 	if (unlikely(valign)) {
1642 		bool palign = (pte_pfn(pte) & contmask) == contmask;
1643 
1644 		if (unlikely(palign &&
1645 		    pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)))
1646 			__contpte_try_fold(mm, addr, ptep, pte);
1647 	}
1648 }
1649 
1650 static __always_inline void contpte_try_unfold(struct mm_struct *mm,
1651 				unsigned long addr, pte_t *ptep, pte_t pte)
1652 {
1653 	if (unlikely(pte_valid_cont(pte)))
1654 		__contpte_try_unfold(mm, addr, ptep, pte);
1655 }
1656 
1657 #define pte_batch_hint pte_batch_hint
1658 static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
1659 {
1660 	if (!pte_valid_cont(pte))
1661 		return 1;
1662 
1663 	return CONT_PTES - (((unsigned long)ptep >> 3) & (CONT_PTES - 1));
1664 }
1665 
1666 /*
1667  * The below functions constitute the public API that arm64 presents to the
1668  * core-mm to manipulate PTE entries within their page tables (or at least this
1669  * is the subset of the API that arm64 needs to implement). These public
1670  * versions will automatically and transparently apply the contiguous bit where
1671  * it makes sense to do so. Therefore any users that are contig-aware (e.g.
1672  * hugetlb, kernel mapper) should NOT use these APIs, but instead use the
1673  * private versions, which are prefixed with double underscore. All of these
1674  * APIs except for ptep_get_lockless() are expected to be called with the PTL
1675  * held. Although the contiguous bit is considered private to the
1676  * implementation, it is deliberately allowed to leak through the getters (e.g.
1677  * ptep_get()), back to core code. This is required so that pte_leaf_size() can
1678  * provide an accurate size for perf_get_pgtable_size(). But this leakage means
1679  * its possible a pte will be passed to a setter with the contiguous bit set, so
1680  * we explicitly clear the contiguous bit in those cases to prevent accidentally
1681  * setting it in the pgtable.
1682  */
1683 
1684 #define ptep_get ptep_get
1685 static inline pte_t ptep_get(pte_t *ptep)
1686 {
1687 	pte_t pte = __ptep_get(ptep);
1688 
1689 	if (likely(!pte_valid_cont(pte)))
1690 		return pte;
1691 
1692 	return contpte_ptep_get(ptep, pte);
1693 }
1694 
1695 #define ptep_get_lockless ptep_get_lockless
1696 static inline pte_t ptep_get_lockless(pte_t *ptep)
1697 {
1698 	pte_t pte = __ptep_get(ptep);
1699 
1700 	if (likely(!pte_valid_cont(pte)))
1701 		return pte;
1702 
1703 	return contpte_ptep_get_lockless(ptep);
1704 }
1705 
1706 static inline void set_pte(pte_t *ptep, pte_t pte)
1707 {
1708 	/*
1709 	 * We don't have the mm or vaddr so cannot unfold contig entries (since
1710 	 * it requires tlb maintenance). set_pte() is not used in core code, so
1711 	 * this should never even be called. Regardless do our best to service
1712 	 * any call and emit a warning if there is any attempt to set a pte on
1713 	 * top of an existing contig range.
1714 	 */
1715 	pte_t orig_pte = __ptep_get(ptep);
1716 
1717 	WARN_ON_ONCE(pte_valid_cont(orig_pte));
1718 	__set_pte(ptep, pte_mknoncont(pte));
1719 }
1720 
1721 #define set_ptes set_ptes
1722 static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
1723 				pte_t *ptep, pte_t pte, unsigned int nr)
1724 {
1725 	pte = pte_mknoncont(pte);
1726 
1727 	if (likely(nr == 1)) {
1728 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1729 		__set_ptes(mm, addr, ptep, pte, 1);
1730 		contpte_try_fold(mm, addr, ptep, pte);
1731 	} else {
1732 		contpte_set_ptes(mm, addr, ptep, pte, nr);
1733 	}
1734 }
1735 
1736 static inline void pte_clear(struct mm_struct *mm,
1737 				unsigned long addr, pte_t *ptep)
1738 {
1739 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1740 	__pte_clear(mm, addr, ptep);
1741 }
1742 
1743 #define clear_full_ptes clear_full_ptes
1744 static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1745 				pte_t *ptep, unsigned int nr, int full)
1746 {
1747 	if (likely(nr == 1)) {
1748 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1749 		__clear_full_ptes(mm, addr, ptep, nr, full);
1750 	} else {
1751 		contpte_clear_full_ptes(mm, addr, ptep, nr, full);
1752 	}
1753 }
1754 
1755 #define get_and_clear_full_ptes get_and_clear_full_ptes
1756 static inline pte_t get_and_clear_full_ptes(struct mm_struct *mm,
1757 				unsigned long addr, pte_t *ptep,
1758 				unsigned int nr, int full)
1759 {
1760 	pte_t pte;
1761 
1762 	if (likely(nr == 1)) {
1763 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1764 		pte = __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1765 	} else {
1766 		pte = contpte_get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1767 	}
1768 
1769 	return pte;
1770 }
1771 
1772 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1773 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
1774 				unsigned long addr, pte_t *ptep)
1775 {
1776 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1777 	return __ptep_get_and_clear(mm, addr, ptep);
1778 }
1779 
1780 static inline bool ptep_try_set(pte_t *ptep, pte_t new_pte)
1781 {
1782 	pteval_t old = 0;
1783 
1784 	if (!try_cmpxchg(&pte_val(*ptep), &old, pte_val(new_pte)))
1785 		return false;
1786 
1787 	/*
1788 	 * The store must be complete by the time this returns, but the caller
1789 	 * may be in lazy MMU mode, where __set_pte_complete() would defer the
1790 	 * barriers. Issue them directly.
1791 	 */
1792 	emit_pte_barriers();
1793 	return true;
1794 }
1795 #define ptep_try_set ptep_try_set
1796 
1797 /*
1798  * arm64 mandates break-before-make: a cleared kernel PTE must have its TLB
1799  * invalidated before a different page is installed in its place. The broadcast
1800  * TLBI is an instruction, not an IPI, so this is safe with interrupts disabled.
1801  */
1802 static inline void flush_tlb_before_set(unsigned long addr)
1803 {
1804 	flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
1805 }
1806 #define flush_tlb_before_set flush_tlb_before_set
1807 
1808 #define test_and_clear_young_ptes test_and_clear_young_ptes
1809 static inline bool test_and_clear_young_ptes(struct vm_area_struct *vma,
1810 		unsigned long addr, pte_t *ptep, unsigned int nr)
1811 {
1812 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1813 		return __ptep_test_and_clear_young(vma, addr, ptep);
1814 
1815 	return contpte_test_and_clear_young_ptes(vma, addr, ptep, nr);
1816 }
1817 
1818 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1819 static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
1820 		unsigned long addr, pte_t *ptep)
1821 {
1822 	return test_and_clear_young_ptes(vma, addr, ptep, 1);
1823 }
1824 
1825 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1826 static inline bool ptep_clear_flush_young(struct vm_area_struct *vma,
1827 		unsigned long addr, pte_t *ptep)
1828 {
1829 	pte_t orig_pte = __ptep_get(ptep);
1830 
1831 	if (likely(!pte_valid_cont(orig_pte)))
1832 		return __ptep_clear_flush_young(vma, addr, ptep);
1833 
1834 	return contpte_clear_flush_young_ptes(vma, addr, ptep, 1);
1835 }
1836 
1837 #define clear_flush_young_ptes clear_flush_young_ptes
1838 static inline bool clear_flush_young_ptes(struct vm_area_struct *vma,
1839 		unsigned long addr, pte_t *ptep, unsigned int nr)
1840 {
1841 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1842 		return __ptep_clear_flush_young(vma, addr, ptep);
1843 
1844 	return contpte_clear_flush_young_ptes(vma, addr, ptep, nr);
1845 }
1846 
1847 #define wrprotect_ptes wrprotect_ptes
1848 static __always_inline void wrprotect_ptes(struct mm_struct *mm,
1849 				unsigned long addr, pte_t *ptep, unsigned int nr)
1850 {
1851 	if (likely(nr == 1)) {
1852 		/*
1853 		 * Optimization: wrprotect_ptes() can only be called for present
1854 		 * ptes so we only need to check contig bit as condition for
1855 		 * unfold, and we can remove the contig bit from the pte we read
1856 		 * to avoid re-reading. This speeds up fork() which is sensitive
1857 		 * for order-0 folios. Equivalent to contpte_try_unfold().
1858 		 */
1859 		pte_t orig_pte = __ptep_get(ptep);
1860 
1861 		if (unlikely(pte_cont(orig_pte))) {
1862 			__contpte_try_unfold(mm, addr, ptep, orig_pte);
1863 			orig_pte = pte_mknoncont(orig_pte);
1864 		}
1865 		___ptep_set_wrprotect(mm, addr, ptep, orig_pte);
1866 	} else {
1867 		contpte_wrprotect_ptes(mm, addr, ptep, nr);
1868 	}
1869 }
1870 
1871 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1872 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1873 				unsigned long addr, pte_t *ptep)
1874 {
1875 	wrprotect_ptes(mm, addr, ptep, 1);
1876 }
1877 
1878 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1879 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
1880 				unsigned long addr, pte_t *ptep,
1881 				pte_t entry, int dirty)
1882 {
1883 	pte_t orig_pte = __ptep_get(ptep);
1884 
1885 	entry = pte_mknoncont(entry);
1886 
1887 	if (likely(!pte_valid_cont(orig_pte)))
1888 		return __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1889 
1890 	return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1891 }
1892 
1893 #define clear_young_dirty_ptes clear_young_dirty_ptes
1894 static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
1895 					  unsigned long addr, pte_t *ptep,
1896 					  unsigned int nr, cydp_t flags)
1897 {
1898 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1899 		__clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1900 	else
1901 		contpte_clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1902 }
1903 
1904 #else /* CONFIG_ARM64_CONTPTE */
1905 
1906 #define ptep_get				__ptep_get
1907 #define set_pte					__set_pte
1908 #define set_ptes				__set_ptes
1909 #define pte_clear				__pte_clear
1910 #define clear_full_ptes				__clear_full_ptes
1911 #define get_and_clear_full_ptes			__get_and_clear_full_ptes
1912 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1913 #define ptep_get_and_clear			__ptep_get_and_clear
1914 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1915 #define ptep_test_and_clear_young		__ptep_test_and_clear_young
1916 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1917 #define ptep_clear_flush_young			__ptep_clear_flush_young
1918 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1919 #define ptep_set_wrprotect			__ptep_set_wrprotect
1920 #define wrprotect_ptes				__wrprotect_ptes
1921 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1922 #define ptep_set_access_flags			__ptep_set_access_flags
1923 #define clear_young_dirty_ptes			__clear_young_dirty_ptes
1924 
1925 #endif /* CONFIG_ARM64_CONTPTE */
1926 
1927 #endif /* !__ASSEMBLER__ */
1928 
1929 #endif /* __ASM_PGTABLE_H */
1930