xref: /linux/arch/arm64/include/asm/pgtable.h (revision 570f7e331f5febb30f1384817463c7e42b65ca7d)
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 #define pte_ERROR(e)	\
111 	pr_err("%s:%d: bad pte %016llx.\n", __FILE__, __LINE__, pte_val(e))
112 
113 #ifdef CONFIG_ARM64_PA_BITS_52
114 static inline phys_addr_t __pte_to_phys(pte_t pte)
115 {
116 	pte_val(pte) &= ~PTE_MAYBE_SHARED;
117 	return (pte_val(pte) & PTE_ADDR_LOW) |
118 		((pte_val(pte) & PTE_ADDR_HIGH) << PTE_ADDR_HIGH_SHIFT);
119 }
120 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
121 {
122 	return (phys | (phys >> PTE_ADDR_HIGH_SHIFT)) & PHYS_TO_PTE_ADDR_MASK;
123 }
124 #else
125 static inline phys_addr_t __pte_to_phys(pte_t pte)
126 {
127 	return pte_val(pte) & PTE_ADDR_LOW;
128 }
129 
130 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
131 {
132 	return phys;
133 }
134 #endif
135 
136 #define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
137 #define pfn_pte(pfn,prot)	\
138 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
139 
140 #define pte_none(pte)		(!pte_val(pte))
141 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
142 
143 #define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))
144 #define pte_present_invalid(pte) \
145 	((pte_val(pte) & (PTE_VALID | PTE_PRESENT_INVALID)) == PTE_PRESENT_INVALID)
146 
147 /*
148  * The following only work if pte_present(). Undefined behaviour otherwise.
149  */
150 static __always_inline bool pte_present(pte_t pte)
151 {
152 	return pte_valid(pte) || pte_present_invalid(pte);
153 }
154 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
155 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
156 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
157 #define pte_rdonly(pte)		(!!(pte_val(pte) & PTE_RDONLY))
158 #define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
159 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
160 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
161 #define pte_tagged(pte)		((pte_val(pte) & PTE_ATTRINDX_MASK) == \
162 				 PTE_ATTRINDX(MT_NORMAL_TAGGED))
163 
164 #define pte_cont_addr_end(addr, end)						\
165 ({	unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK;	\
166 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
167 })
168 
169 #define pmd_cont_addr_end(addr, end)						\
170 ({	unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK;	\
171 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
172 })
173 
174 #define pte_hw_dirty(pte)	(pte_write(pte) && !pte_rdonly(pte))
175 #define pte_sw_dirty(pte)	(!!(pte_val(pte) & PTE_DIRTY))
176 #define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))
177 
178 /*
179  * Execute-only user mappings do not have the PTE_USER bit set. All valid
180  * kernel mappings have the PTE_UXN bit set.
181  */
182 #define pte_valid_not_user(pte) \
183 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
184 /*
185  * Returns true if the pte is valid and has the contiguous bit set.
186  */
187 #define pte_valid_cont(pte)	(pte_valid(pte) && pte_cont(pte))
188 /*
189  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
190  * so that we don't erroneously return false for pages that have been
191  * remapped as PROT_NONE but are yet to be flushed from the TLB.
192  * Note that we can't make any assumptions based on the state of the access
193  * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the
194  * TLB.
195  */
196 #define pte_accessible(mm, pte)	\
197 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
198 
199 static inline bool por_el0_allows_pkey(u8 pkey, bool write, bool execute)
200 {
201 	u64 por;
202 
203 	if (!system_supports_poe())
204 		return true;
205 
206 	por = read_sysreg_s(SYS_POR_EL0);
207 
208 	if (write)
209 		return por_elx_allows_write(por, pkey);
210 
211 	if (execute)
212 		return por_elx_allows_exec(por, pkey);
213 
214 	return por_elx_allows_read(por, pkey);
215 }
216 
217 /*
218  * p??_access_permitted() is true for valid user mappings (PTE_USER
219  * bit set, subject to the write permission check). For execute-only
220  * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
221  * not set) must return false. PROT_NONE mappings do not have the
222  * PTE_VALID bit set.
223  */
224 #define pte_access_permitted_no_overlay(pte, write) \
225 	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
226 #define pte_access_permitted(pte, write) \
227 	(pte_access_permitted_no_overlay(pte, write) && \
228 	por_el0_allows_pkey(FIELD_GET(PTE_PO_IDX_MASK, pte_val(pte)), write, false))
229 #define pmd_access_permitted(pmd, write) \
230 	(pte_access_permitted(pmd_pte(pmd), (write)))
231 #define pud_access_permitted(pud, write) \
232 	(pte_access_permitted(pud_pte(pud), (write)))
233 
234 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
235 {
236 	pte_val(pte) &= ~pgprot_val(prot);
237 	return pte;
238 }
239 
240 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
241 {
242 	pte_val(pte) |= pgprot_val(prot);
243 	return pte;
244 }
245 
246 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
247 {
248 	pmd_val(pmd) &= ~pgprot_val(prot);
249 	return pmd;
250 }
251 
252 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
253 {
254 	pmd_val(pmd) |= pgprot_val(prot);
255 	return pmd;
256 }
257 
258 static inline pte_t pte_mkwrite_novma(pte_t pte)
259 {
260 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
261 	if (pte_sw_dirty(pte))
262 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
263 	return pte;
264 }
265 
266 static inline pte_t pte_mkclean(pte_t pte)
267 {
268 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
269 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
270 
271 	return pte;
272 }
273 
274 static inline pte_t pte_mkdirty(pte_t pte)
275 {
276 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
277 
278 	if (pte_write(pte))
279 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
280 
281 	return pte;
282 }
283 
284 static inline pte_t pte_wrprotect(pte_t pte)
285 {
286 	/*
287 	 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
288 	 * clear), set the PTE_DIRTY bit.
289 	 */
290 	if (pte_hw_dirty(pte))
291 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
292 
293 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
294 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
295 	return pte;
296 }
297 
298 static inline pte_t pte_mkold(pte_t pte)
299 {
300 	return clear_pte_bit(pte, __pgprot(PTE_AF));
301 }
302 
303 static inline pte_t pte_mkyoung(pte_t pte)
304 {
305 	return set_pte_bit(pte, __pgprot(PTE_AF));
306 }
307 
308 static inline pte_t pte_mkspecial(pte_t pte)
309 {
310 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
311 }
312 
313 static inline pte_t pte_mkcont(pte_t pte)
314 {
315 	return set_pte_bit(pte, __pgprot(PTE_CONT));
316 }
317 
318 static inline pte_t pte_mknoncont(pte_t pte)
319 {
320 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
321 }
322 
323 static inline pte_t pte_mkvalid_k(pte_t pte)
324 {
325 	pte = clear_pte_bit(pte, __pgprot(PTE_PRESENT_INVALID));
326 	pte = set_pte_bit(pte, __pgprot(PTE_PRESENT_VALID_KERNEL));
327 	return pte;
328 }
329 
330 static inline pte_t pte_mkinvalid(pte_t pte)
331 {
332 	pte = set_pte_bit(pte, __pgprot(PTE_PRESENT_INVALID));
333 	pte = clear_pte_bit(pte, __pgprot(PTE_VALID));
334 	return pte;
335 }
336 
337 static inline pmd_t pmd_mkcont(pmd_t pmd)
338 {
339 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
340 }
341 
342 static inline pmd_t pmd_mknoncont(pmd_t pmd)
343 {
344 	return __pmd(pmd_val(pmd) & ~PMD_SECT_CONT);
345 }
346 
347 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
348 static inline int pte_uffd(pte_t pte)
349 {
350 	return !!(pte_val(pte) & PTE_UFFD);
351 }
352 
353 static inline pte_t pte_mkuffd(pte_t pte)
354 {
355 	return pte_wrprotect(set_pte_bit(pte, __pgprot(PTE_UFFD)));
356 }
357 
358 static inline pte_t pte_clear_uffd(pte_t pte)
359 {
360 	return clear_pte_bit(pte, __pgprot(PTE_UFFD));
361 }
362 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
363 
364 static inline void __set_pte_nosync(pte_t *ptep, pte_t pte)
365 {
366 	WRITE_ONCE(*ptep, pte);
367 }
368 
369 static inline void __set_pte_complete(pte_t pte)
370 {
371 	/*
372 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
373 	 * has the necessary barriers.
374 	 */
375 	if (pte_valid_not_user(pte))
376 		queue_pte_barriers();
377 }
378 
379 static inline void __set_pte(pte_t *ptep, pte_t pte)
380 {
381 	__set_pte_nosync(ptep, pte);
382 	__set_pte_complete(pte);
383 }
384 
385 static inline pte_t __ptep_get(pte_t *ptep)
386 {
387 	return READ_ONCE(*ptep);
388 }
389 
390 extern void __sync_icache_dcache(pte_t pteval);
391 bool pgattr_change_is_safe(pteval_t old, pteval_t new);
392 
393 /*
394  * PTE bits configuration in the presence of hardware Dirty Bit Management
395  * (PTE_WRITE == PTE_DBM):
396  *
397  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
398  *   0      0      |   1           0          0
399  *   0      1      |   1           1          0
400  *   1      0      |   1           0          1
401  *   1      1      |   0           1          x
402  *
403  * When hardware DBM is not present, the software PTE_DIRTY bit is updated via
404  * the page fault mechanism. Checking the dirty status of a pte becomes:
405  *
406  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
407  */
408 
409 static inline void __check_safe_pte_update(struct mm_struct *mm, pte_t *ptep,
410 					   pte_t pte)
411 {
412 	pte_t old_pte;
413 
414 	if (!IS_ENABLED(CONFIG_DEBUG_VM))
415 		return;
416 
417 	old_pte = __ptep_get(ptep);
418 
419 	if (!pte_valid(old_pte) || !pte_valid(pte))
420 		return;
421 	if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
422 		return;
423 
424 	/*
425 	 * Check for potential race with hardware updates of the pte
426 	 * (__ptep_set_access_flags safely changes valid ptes without going
427 	 * through an invalid entry).
428 	 */
429 	VM_WARN_ONCE(!pte_young(pte),
430 		     "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
431 		     __func__, pte_val(old_pte), pte_val(pte));
432 	VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
433 		     "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
434 		     __func__, pte_val(old_pte), pte_val(pte));
435 	VM_WARN_ONCE(!pgattr_change_is_safe(pte_val(old_pte), pte_val(pte)),
436 		     "%s: unsafe attribute change: 0x%016llx -> 0x%016llx",
437 		     __func__, pte_val(old_pte), pte_val(pte));
438 }
439 
440 static inline void __sync_cache_and_tags(pte_t pte, unsigned int nr_pages)
441 {
442 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
443 		__sync_icache_dcache(pte);
444 
445 	/*
446 	 * If the PTE would provide user space access to the tags associated
447 	 * with it then ensure that the MTE tags are synchronised.  Although
448 	 * pte_access_permitted_no_overlay() returns false for exec only
449 	 * mappings, they don't expose tags (instruction fetches don't check
450 	 * tags).
451 	 */
452 	if (system_supports_mte() && pte_access_permitted_no_overlay(pte, false) &&
453 	    !pte_special(pte) && pte_tagged(pte))
454 		mte_sync_tags(pte, nr_pages);
455 }
456 
457 /*
458  * Select all bits except the pfn
459  */
460 #define pte_pgprot pte_pgprot
461 static inline pgprot_t pte_pgprot(pte_t pte)
462 {
463 	unsigned long pfn = pte_pfn(pte);
464 
465 	return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
466 }
467 
468 #define pte_advance_pfn pte_advance_pfn
469 static inline pte_t pte_advance_pfn(pte_t pte, unsigned long nr)
470 {
471 	return pfn_pte(pte_pfn(pte) + nr, pte_pgprot(pte));
472 }
473 
474 /*
475  * Hugetlb definitions.
476  */
477 #define HUGE_MAX_HSTATE		4
478 #define HPAGE_SHIFT		PMD_SHIFT
479 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
480 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
481 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
482 
483 static inline pte_t pgd_pte(pgd_t pgd)
484 {
485 	return __pte(pgd_val(pgd));
486 }
487 
488 static inline pte_t p4d_pte(p4d_t p4d)
489 {
490 	return __pte(p4d_val(p4d));
491 }
492 
493 static inline pte_t pud_pte(pud_t pud)
494 {
495 	return __pte(pud_val(pud));
496 }
497 
498 static inline pud_t pte_pud(pte_t pte)
499 {
500 	return __pud(pte_val(pte));
501 }
502 
503 static inline pmd_t pud_pmd(pud_t pud)
504 {
505 	return __pmd(pud_val(pud));
506 }
507 
508 static inline pte_t pmd_pte(pmd_t pmd)
509 {
510 	return __pte(pmd_val(pmd));
511 }
512 
513 static inline pmd_t pte_pmd(pte_t pte)
514 {
515 	return __pmd(pte_val(pte));
516 }
517 
518 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
519 {
520 	return __pgprot((pgprot_val(prot) & ~PUD_TYPE_MASK) | PUD_TYPE_SECT);
521 }
522 
523 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
524 {
525 	return __pgprot((pgprot_val(prot) & ~PMD_TYPE_MASK) | PMD_TYPE_SECT);
526 }
527 
528 static inline pte_t pte_swp_mkexclusive(pte_t pte)
529 {
530 	return set_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
531 }
532 
533 static inline bool pte_swp_exclusive(pte_t pte)
534 {
535 	return pte_val(pte) & PTE_SWP_EXCLUSIVE;
536 }
537 
538 static inline pte_t pte_swp_clear_exclusive(pte_t pte)
539 {
540 	return clear_pte_bit(pte, __pgprot(PTE_SWP_EXCLUSIVE));
541 }
542 
543 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
544 static inline pte_t pte_swp_mkuffd(pte_t pte)
545 {
546 	return set_pte_bit(pte, __pgprot(PTE_SWP_UFFD));
547 }
548 
549 static inline int pte_swp_uffd(pte_t pte)
550 {
551 	return !!(pte_val(pte) & PTE_SWP_UFFD);
552 }
553 
554 static inline pte_t pte_swp_clear_uffd(pte_t pte)
555 {
556 	return clear_pte_bit(pte, __pgprot(PTE_SWP_UFFD));
557 }
558 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
559 
560 #ifdef CONFIG_ARCH_HAS_PTE_PROTNONE
561 static inline int pte_protnone(pte_t pte)
562 {
563 	/*
564 	 * pte_present_invalid() tells us that the pte is invalid from HW
565 	 * perspective but present from SW perspective, so the fields are to be
566 	 * interpreted as per the HW layout. The second 2 checks are the unique
567 	 * encoding that we use for PROT_NONE. It is insufficient to only use
568 	 * the first check because we share the same encoding scheme with pmds
569 	 * which support pmd_mkinvalid(), so can be present-invalid without
570 	 * being PROT_NONE.
571 	 */
572 	return pte_present_invalid(pte) && !pte_user(pte) && !pte_user_exec(pte);
573 }
574 
575 static inline int pmd_protnone(pmd_t pmd)
576 {
577 	return pte_protnone(pmd_pte(pmd));
578 }
579 #endif /* CONFIG_ARCH_HAS_PTE_PROTNONE */
580 
581 #define pmd_present(pmd)	pte_present(pmd_pte(pmd))
582 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
583 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
584 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
585 #define pmd_user(pmd)		pte_user(pmd_pte(pmd))
586 #define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
587 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
588 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
589 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
590 #define pmd_mkwrite_novma(pmd)	pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)))
591 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
592 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
593 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
594 #define pmd_mkvalid_k(pmd)	pte_pmd(pte_mkvalid_k(pmd_pte(pmd)))
595 #define pmd_mkinvalid(pmd)	pte_pmd(pte_mkinvalid(pmd_pte(pmd)))
596 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
597 #define pmd_uffd(pmd)	pte_uffd(pmd_pte(pmd))
598 #define pmd_mkuffd(pmd)	pte_pmd(pte_mkuffd(pmd_pte(pmd)))
599 #define pmd_clear_uffd(pmd)	pte_pmd(pte_clear_uffd(pmd_pte(pmd)))
600 #define pmd_swp_uffd(pmd)	pte_swp_uffd(pmd_pte(pmd))
601 #define pmd_swp_mkuffd(pmd)	pte_pmd(pte_swp_mkuffd(pmd_pte(pmd)))
602 #define pmd_swp_clear_uffd(pmd) \
603 				pte_pmd(pte_swp_clear_uffd(pmd_pte(pmd)))
604 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
605 
606 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
607 
608 static inline pmd_t pmd_mkhuge(pmd_t pmd)
609 {
610 	/*
611 	 * It's possible that the pmd is present-invalid on entry
612 	 * and in that case it needs to remain present-invalid on
613 	 * exit. So ensure the VALID bit does not get modified.
614 	 */
615 	pmdval_t mask = PMD_TYPE_MASK & ~PTE_VALID;
616 	pmdval_t val = PMD_TYPE_SECT & ~PTE_VALID;
617 
618 	return __pmd((pmd_val(pmd) & ~mask) | val);
619 }
620 
621 #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP
622 #define pmd_special(pte)	(!!((pmd_val(pte) & PTE_SPECIAL)))
623 static inline pmd_t pmd_mkspecial(pmd_t pmd)
624 {
625 	return set_pmd_bit(pmd, __pgprot(PTE_SPECIAL));
626 }
627 #endif
628 
629 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
630 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
631 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
632 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
633 
634 #define pud_young(pud)		pte_young(pud_pte(pud))
635 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
636 #define pud_mkwrite_novma(pud)	pte_pud(pte_mkwrite_novma(pud_pte(pud)))
637 #define pud_mkvalid_k(pud)	pte_pud(pte_mkvalid_k(pud_pte(pud)))
638 #define pud_write(pud)		pte_write(pud_pte(pud))
639 
640 static inline pud_t pud_mkhuge(pud_t pud)
641 {
642 	/*
643 	 * It's possible that the pud is present-invalid on entry
644 	 * and in that case it needs to remain present-invalid on
645 	 * exit. So ensure the VALID bit does not get modified.
646 	 */
647 	pudval_t mask = PUD_TYPE_MASK & ~PTE_VALID;
648 	pudval_t val = PUD_TYPE_SECT & ~PTE_VALID;
649 
650 	return __pud((pud_val(pud) & ~mask) | val);
651 }
652 
653 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
654 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
655 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
656 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
657 
658 #define pmd_pgprot pmd_pgprot
659 static inline pgprot_t pmd_pgprot(pmd_t pmd)
660 {
661 	unsigned long pfn = pmd_pfn(pmd);
662 
663 	return __pgprot(pmd_val(pfn_pmd(pfn, __pgprot(0))) ^ pmd_val(pmd));
664 }
665 
666 #define pud_pgprot pud_pgprot
667 static inline pgprot_t pud_pgprot(pud_t pud)
668 {
669 	unsigned long pfn = pud_pfn(pud);
670 
671 	return __pgprot(pud_val(pfn_pud(pfn, __pgprot(0))) ^ pud_val(pud));
672 }
673 
674 static inline void __set_ptes_anysz(struct mm_struct *mm, unsigned long addr,
675 				    pte_t *ptep, pte_t pte, unsigned int nr,
676 				    unsigned long pgsize)
677 {
678 	unsigned long stride = pgsize >> PAGE_SHIFT;
679 
680 	switch (pgsize) {
681 	case PAGE_SIZE:
682 		page_table_check_ptes_set(mm, addr, ptep, pte, nr);
683 		break;
684 	case PMD_SIZE:
685 		page_table_check_pmds_set(mm, addr, (pmd_t *)ptep,
686 					  pte_pmd(pte), nr);
687 		break;
688 #ifndef __PAGETABLE_PMD_FOLDED
689 	case PUD_SIZE:
690 		page_table_check_puds_set(mm, addr, (pud_t *)ptep,
691 					  pte_pud(pte), nr);
692 		break;
693 #endif
694 	default:
695 		VM_WARN_ON(1);
696 	}
697 
698 	__sync_cache_and_tags(pte, nr * stride);
699 
700 	for (;;) {
701 		__check_safe_pte_update(mm, ptep, pte);
702 		__set_pte_nosync(ptep, pte);
703 		if (--nr == 0)
704 			break;
705 		ptep++;
706 		pte = pte_advance_pfn(pte, stride);
707 	}
708 
709 	__set_pte_complete(pte);
710 }
711 
712 static inline void __set_ptes(struct mm_struct *mm, unsigned long addr,
713 			      pte_t *ptep, pte_t pte, unsigned int nr)
714 {
715 	__set_ptes_anysz(mm, addr, ptep, pte, nr, PAGE_SIZE);
716 }
717 
718 static inline void __set_pmds(struct mm_struct *mm, unsigned long addr,
719 			      pmd_t *pmdp, pmd_t pmd, unsigned int nr)
720 {
721 	__set_ptes_anysz(mm, addr, (pte_t *)pmdp, pmd_pte(pmd), nr, PMD_SIZE);
722 }
723 #define set_pmd_at(mm, addr, pmdp, pmd) __set_pmds(mm, addr, pmdp, pmd, 1)
724 
725 static inline void __set_puds(struct mm_struct *mm, unsigned long addr,
726 			      pud_t *pudp, pud_t pud, unsigned int nr)
727 {
728 	__set_ptes_anysz(mm, addr, (pte_t *)pudp, pud_pte(pud), nr, PUD_SIZE);
729 }
730 #define set_pud_at(mm, addr, pudp, pud) __set_puds(mm, addr, pudp, pud, 1)
731 
732 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
733 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
734 
735 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
736 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
737 
738 #define __pgprot_modify(prot,mask,bits) \
739 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
740 
741 #define pgprot_nx(prot) \
742 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
743 
744 #define pgprot_decrypted(prot) \
745 	__pgprot_modify(prot, PROT_NS_SHARED, PROT_NS_SHARED)
746 #define pgprot_encrypted(prot) \
747 	__pgprot_modify(prot, PROT_NS_SHARED, 0)
748 
749 /*
750  * Mark the prot value as uncacheable and unbufferable.
751  */
752 #define pgprot_noncached(prot) \
753 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
754 #define pgprot_writecombine(prot) \
755 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
756 #define pgprot_device(prot) \
757 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
758 #define pgprot_tagged(prot) \
759 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
760 #define pgprot_mhp	pgprot_tagged
761 /*
762  * DMA allocations for non-coherent devices use what the Arm architecture calls
763  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
764  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
765  * is intended for MMIO and thus forbids speculation, preserves access size,
766  * requires strict alignment and can also force write responses to come from the
767  * endpoint.
768  */
769 #define pgprot_dmacoherent(prot) \
770 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
771 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
772 
773 #define __HAVE_PHYS_MEM_ACCESS_PROT
774 struct file;
775 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
776 				     unsigned long size, pgprot_t vma_prot);
777 
778 #define pmd_none(pmd)		(!pmd_val(pmd))
779 
780 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
781 				 PMD_TYPE_TABLE)
782 
783 #define pmd_leaf pmd_leaf
784 static inline bool pmd_leaf(pmd_t pmd)
785 {
786 	return pmd_present(pmd) && !pmd_table(pmd);
787 }
788 
789 #define pmd_bad(pmd)		(!pmd_table(pmd))
790 
791 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
792 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
793 
794 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
795 static inline int pmd_trans_huge(pmd_t pmd)
796 {
797 	/*
798 	 * If pmd is present-invalid, pmd_table() won't detect it
799 	 * as a table, so force the valid bit for the comparison.
800 	 */
801 	return pmd_present(pmd) && !pmd_table(__pmd(pmd_val(pmd) | PTE_VALID));
802 }
803 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
804 
805 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
806 static inline bool pud_table(pud_t pud) { return true; }
807 #else
808 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
809 				 PUD_TYPE_TABLE)
810 #endif
811 
812 extern pgd_t swapper_pg_dir[];
813 extern pgd_t idmap_pg_dir[];
814 extern pgd_t tramp_pg_dir[];
815 extern pgd_t reserved_pg_dir[];
816 
817 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
818 
819 static inline bool in_swapper_pgdir(void *addr)
820 {
821 	return ((unsigned long)addr & PAGE_MASK) ==
822 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
823 }
824 
825 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
826 {
827 #ifdef __PAGETABLE_PMD_FOLDED
828 	if (in_swapper_pgdir(pmdp)) {
829 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
830 		return;
831 	}
832 #endif /* __PAGETABLE_PMD_FOLDED */
833 
834 	WRITE_ONCE(*pmdp, pmd);
835 
836 	if (pmd_valid(pmd))
837 		queue_pte_barriers();
838 }
839 
840 static inline void pmd_clear(pmd_t *pmdp)
841 {
842 	set_pmd(pmdp, __pmd(0));
843 }
844 
845 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
846 {
847 	return __pmd_to_phys(pmd);
848 }
849 
850 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
851 {
852 	return (unsigned long)__va(pmd_page_paddr(pmd));
853 }
854 
855 /* Find an entry in the third-level page table. */
856 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
857 
858 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
859 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
860 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
861 
862 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
863 
864 /* use ONLY for statically allocated translation tables */
865 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
866 
867 #if CONFIG_PGTABLE_LEVELS > 2
868 
869 #define pmd_ERROR(e)	\
870 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
871 
872 #define pud_none(pud)		(!pud_val(pud))
873 #define pud_bad(pud)		((pud_val(pud) & PUD_TYPE_MASK) != \
874 				 PUD_TYPE_TABLE)
875 #define pud_present(pud)	pte_present(pud_pte(pud))
876 #ifndef __PAGETABLE_PMD_FOLDED
877 #define pud_leaf pud_leaf
878 static inline bool pud_leaf(pud_t pud)
879 {
880 	return pud_present(pud) && !pud_table(pud);
881 }
882 #else
883 #define pud_leaf(pud)		false
884 #endif
885 #define pud_valid(pud)		pte_valid(pud_pte(pud))
886 #define pud_user(pud)		pte_user(pud_pte(pud))
887 #define pud_user_exec(pud)	pte_user_exec(pud_pte(pud))
888 
889 static inline bool pgtable_l4_enabled(void);
890 
891 static inline void set_pud(pud_t *pudp, pud_t pud)
892 {
893 	if (!pgtable_l4_enabled() && in_swapper_pgdir(pudp)) {
894 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
895 		return;
896 	}
897 
898 	WRITE_ONCE(*pudp, pud);
899 
900 	if (pud_valid(pud))
901 		queue_pte_barriers();
902 }
903 
904 static inline void pud_clear(pud_t *pudp)
905 {
906 	set_pud(pudp, __pud(0));
907 }
908 
909 static inline phys_addr_t pud_page_paddr(pud_t pud)
910 {
911 	return __pud_to_phys(pud);
912 }
913 
914 static inline pmd_t *pud_pgtable(pud_t pud)
915 {
916 	return (pmd_t *)__va(pud_page_paddr(pud));
917 }
918 
919 /* Find an entry in the second-level page table. */
920 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
921 
922 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
923 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
924 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
925 
926 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
927 
928 /* use ONLY for statically allocated translation tables */
929 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
930 
931 #else
932 
933 #define pud_valid(pud)		false
934 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
935 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
936 
937 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
938 #define pmd_set_fixmap(addr)		NULL
939 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
940 #define pmd_clear_fixmap()
941 
942 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
943 
944 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
945 
946 #if CONFIG_PGTABLE_LEVELS > 3
947 
948 static __always_inline bool pgtable_l4_enabled(void)
949 {
950 	if (CONFIG_PGTABLE_LEVELS > 4 || !IS_ENABLED(CONFIG_ARM64_LPA2))
951 		return true;
952 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
953 		return vabits_actual == VA_BITS;
954 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
955 }
956 
957 static inline bool mm_pud_folded(const struct mm_struct *mm)
958 {
959 	return !pgtable_l4_enabled();
960 }
961 #define mm_pud_folded  mm_pud_folded
962 
963 #define pud_ERROR(e)	\
964 	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
965 
966 #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
967 #define p4d_bad(p4d)		(pgtable_l4_enabled() && \
968 				((p4d_val(p4d) & P4D_TYPE_MASK) != \
969 				 P4D_TYPE_TABLE))
970 #define p4d_present(p4d)	(!p4d_none(p4d))
971 
972 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
973 {
974 	if (in_swapper_pgdir(p4dp)) {
975 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
976 		return;
977 	}
978 
979 	WRITE_ONCE(*p4dp, p4d);
980 	queue_pte_barriers();
981 }
982 
983 static inline void p4d_clear(p4d_t *p4dp)
984 {
985 	if (pgtable_l4_enabled())
986 		set_p4d(p4dp, __p4d(0));
987 }
988 
989 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
990 {
991 	return __p4d_to_phys(p4d);
992 }
993 
994 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
995 
996 static inline pud_t *p4d_to_folded_pud(p4d_t *p4dp, unsigned long addr)
997 {
998 	/* Ensure that 'p4dp' indexes a page table according to 'addr' */
999 	VM_BUG_ON(((addr >> P4D_SHIFT) ^ ((u64)p4dp >> 3)) % PTRS_PER_P4D);
1000 
1001 	return (pud_t *)PTR_ALIGN_DOWN(p4dp, PAGE_SIZE) + pud_index(addr);
1002 }
1003 
1004 static inline pud_t *p4d_pgtable(p4d_t p4d)
1005 {
1006 	return (pud_t *)__va(p4d_page_paddr(p4d));
1007 }
1008 
1009 static inline phys_addr_t pud_offset_phys(p4d_t *p4dp, unsigned long addr)
1010 {
1011 	VM_WARN_ON_ONCE(!pgtable_l4_enabled());
1012 
1013 	return p4d_page_paddr(READ_ONCE(*p4dp)) + pud_index(addr) * sizeof(pud_t);
1014 }
1015 
1016 static inline
1017 pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long addr)
1018 {
1019 	if (!pgtable_l4_enabled())
1020 		return p4d_to_folded_pud(p4dp, addr);
1021 	return (pud_t *)__va(p4d_page_paddr(p4d)) + pud_index(addr);
1022 }
1023 #define pud_offset_lockless pud_offset_lockless
1024 
1025 static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long addr)
1026 {
1027 	return pud_offset_lockless(p4dp, READ_ONCE(*p4dp), addr);
1028 }
1029 #define pud_offset	pud_offset
1030 
1031 static inline pud_t *pud_set_fixmap(unsigned long addr)
1032 {
1033 	if (!pgtable_l4_enabled())
1034 		return NULL;
1035 	return (pud_t *)set_fixmap_offset(FIX_PUD, addr);
1036 }
1037 
1038 static inline pud_t *pud_set_fixmap_offset(p4d_t *p4dp, unsigned long addr)
1039 {
1040 	if (!pgtable_l4_enabled())
1041 		return p4d_to_folded_pud(p4dp, addr);
1042 	return pud_set_fixmap(pud_offset_phys(p4dp, addr));
1043 }
1044 
1045 static inline void pud_clear_fixmap(void)
1046 {
1047 	if (pgtable_l4_enabled())
1048 		clear_fixmap(FIX_PUD);
1049 }
1050 
1051 /* use ONLY for statically allocated translation tables */
1052 static inline pud_t *pud_offset_kimg(p4d_t *p4dp, u64 addr)
1053 {
1054 	if (!pgtable_l4_enabled())
1055 		return p4d_to_folded_pud(p4dp, addr);
1056 	return (pud_t *)__phys_to_kimg(pud_offset_phys(p4dp, addr));
1057 }
1058 
1059 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
1060 
1061 #else
1062 
1063 static inline bool pgtable_l4_enabled(void) { return false; }
1064 
1065 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
1066 
1067 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
1068 #define pud_set_fixmap(addr)		NULL
1069 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
1070 #define pud_clear_fixmap()
1071 
1072 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
1073 
1074 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
1075 
1076 #if CONFIG_PGTABLE_LEVELS > 4
1077 
1078 static __always_inline bool pgtable_l5_enabled(void)
1079 {
1080 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
1081 		return vabits_actual == VA_BITS;
1082 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
1083 }
1084 
1085 static inline bool mm_p4d_folded(const struct mm_struct *mm)
1086 {
1087 	return !pgtable_l5_enabled();
1088 }
1089 #define mm_p4d_folded  mm_p4d_folded
1090 
1091 #define p4d_ERROR(e)	\
1092 	pr_err("%s:%d: bad p4d %016llx.\n", __FILE__, __LINE__, p4d_val(e))
1093 
1094 #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
1095 #define pgd_bad(pgd)		(pgtable_l5_enabled() && \
1096 				((pgd_val(pgd) & PGD_TYPE_MASK) != \
1097 				 PGD_TYPE_TABLE))
1098 #define pgd_present(pgd)	(!pgd_none(pgd))
1099 
1100 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
1101 {
1102 	if (in_swapper_pgdir(pgdp)) {
1103 		set_swapper_pgd(pgdp, __pgd(pgd_val(pgd)));
1104 		return;
1105 	}
1106 
1107 	WRITE_ONCE(*pgdp, pgd);
1108 	queue_pte_barriers();
1109 }
1110 
1111 static inline void pgd_clear(pgd_t *pgdp)
1112 {
1113 	if (pgtable_l5_enabled())
1114 		set_pgd(pgdp, __pgd(0));
1115 }
1116 
1117 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
1118 {
1119 	return __pgd_to_phys(pgd);
1120 }
1121 
1122 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1123 
1124 static inline p4d_t *pgd_to_folded_p4d(pgd_t *pgdp, unsigned long addr)
1125 {
1126 	/* Ensure that 'pgdp' indexes a page table according to 'addr' */
1127 	VM_BUG_ON(((addr >> PGDIR_SHIFT) ^ ((u64)pgdp >> 3)) % PTRS_PER_PGD);
1128 
1129 	return (p4d_t *)PTR_ALIGN_DOWN(pgdp, PAGE_SIZE) + p4d_index(addr);
1130 }
1131 
1132 static inline phys_addr_t p4d_offset_phys(pgd_t *pgdp, unsigned long addr)
1133 {
1134 	VM_WARN_ON_ONCE(!pgtable_l5_enabled());
1135 
1136 	return pgd_page_paddr(READ_ONCE(*pgdp)) + p4d_index(addr) * sizeof(p4d_t);
1137 }
1138 
1139 static inline
1140 p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1141 {
1142 	if (!pgtable_l5_enabled())
1143 		return pgd_to_folded_p4d(pgdp, addr);
1144 	return (p4d_t *)__va(pgd_page_paddr(pgd)) + p4d_index(addr);
1145 }
1146 #define p4d_offset_lockless p4d_offset_lockless
1147 
1148 static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long addr)
1149 {
1150 	return p4d_offset_lockless(pgdp, READ_ONCE(*pgdp), addr);
1151 }
1152 
1153 static inline p4d_t *p4d_set_fixmap(unsigned long addr)
1154 {
1155 	if (!pgtable_l5_enabled())
1156 		return NULL;
1157 	return (p4d_t *)set_fixmap_offset(FIX_P4D, addr);
1158 }
1159 
1160 static inline p4d_t *p4d_set_fixmap_offset(pgd_t *pgdp, unsigned long addr)
1161 {
1162 	if (!pgtable_l5_enabled())
1163 		return pgd_to_folded_p4d(pgdp, addr);
1164 	return p4d_set_fixmap(p4d_offset_phys(pgdp, addr));
1165 }
1166 
1167 static inline void p4d_clear_fixmap(void)
1168 {
1169 	if (pgtable_l5_enabled())
1170 		clear_fixmap(FIX_P4D);
1171 }
1172 
1173 /* use ONLY for statically allocated translation tables */
1174 static inline p4d_t *p4d_offset_kimg(pgd_t *pgdp, u64 addr)
1175 {
1176 	if (!pgtable_l5_enabled())
1177 		return pgd_to_folded_p4d(pgdp, addr);
1178 	return (p4d_t *)__phys_to_kimg(p4d_offset_phys(pgdp, addr));
1179 }
1180 
1181 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
1182 
1183 #else
1184 
1185 static inline bool pgtable_l5_enabled(void) { return false; }
1186 
1187 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1188 
1189 /* Match p4d_offset folding in <asm/generic/pgtable-nop4d.h> */
1190 #define p4d_set_fixmap(addr)		NULL
1191 #define p4d_set_fixmap_offset(p4dp, addr)	((p4d_t *)p4dp)
1192 #define p4d_clear_fixmap()
1193 
1194 #define p4d_offset_kimg(dir,addr)	((p4d_t *)dir)
1195 
1196 static inline
1197 p4d_t *p4d_offset_lockless_folded(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1198 {
1199 	/*
1200 	 * With runtime folding of the pud, pud_offset_lockless() passes
1201 	 * the 'pgd_t *' we return here to p4d_to_folded_pud(), which
1202 	 * will offset the pointer assuming that it points into
1203 	 * a page-table page. However, the fast GUP path passes us a
1204 	 * pgd_t allocated on the stack and so we must use the original
1205 	 * pointer in 'pgdp' to construct the p4d pointer instead of
1206 	 * using the generic p4d_offset_lockless() implementation.
1207 	 *
1208 	 * Note: reusing the original pointer means that we may
1209 	 * dereference the same (live) page-table entry multiple times.
1210 	 * This is safe because it is still only loaded once in the
1211 	 * context of each level and the CPU guarantees same-address
1212 	 * read-after-read ordering.
1213 	 */
1214 	return p4d_offset(pgdp, addr);
1215 }
1216 #define p4d_offset_lockless p4d_offset_lockless_folded
1217 
1218 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
1219 
1220 #define pgd_ERROR(e)	\
1221 	pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
1222 
1223 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
1224 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
1225 
1226 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
1227 {
1228 	/*
1229 	 * Normal and Normal-Tagged are two different memory types and indices
1230 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
1231 	 */
1232 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
1233 			      PTE_PRESENT_INVALID | PTE_VALID | PTE_WRITE |
1234 			      PTE_GP | PTE_ATTRINDX_MASK | PTE_PO_IDX_MASK;
1235 
1236 	/* preserve the hardware dirty information */
1237 	if (pte_hw_dirty(pte))
1238 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
1239 
1240 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
1241 	/*
1242 	 * If we end up clearing hw dirtiness for a sw-dirty PTE, set hardware
1243 	 * dirtiness again.
1244 	 */
1245 	if (pte_sw_dirty(pte))
1246 		pte = pte_mkdirty(pte);
1247 	return pte;
1248 }
1249 
1250 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1251 {
1252 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
1253 }
1254 
1255 extern int __ptep_set_access_flags_anysz(struct vm_area_struct *vma,
1256 					 unsigned long address, pte_t *ptep,
1257 					 pte_t entry, int dirty,
1258 					 unsigned long pgsize);
1259 
1260 static inline int __ptep_set_access_flags(struct vm_area_struct *vma,
1261 					  unsigned long address, pte_t *ptep,
1262 					  pte_t entry, int dirty)
1263 {
1264 	return __ptep_set_access_flags_anysz(vma, address, ptep, entry, dirty,
1265 					     PAGE_SIZE);
1266 }
1267 
1268 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1269 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1270 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1271 					unsigned long address, pmd_t *pmdp,
1272 					pmd_t entry, int dirty)
1273 {
1274 	return __ptep_set_access_flags_anysz(vma, address, (pte_t *)pmdp,
1275 					     pmd_pte(entry), dirty, PMD_SIZE);
1276 }
1277 #endif
1278 
1279 #ifdef CONFIG_PAGE_TABLE_CHECK
1280 static inline bool pte_user_accessible_page(struct mm_struct *mm, unsigned long addr, pte_t pte)
1281 {
1282 	return pte_valid(pte) && (pte_user(pte) || pte_user_exec(pte));
1283 }
1284 
1285 static inline bool pmd_user_accessible_page(struct mm_struct *mm, unsigned long addr, pmd_t pmd)
1286 {
1287 	return pmd_valid(pmd) && !pmd_table(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
1288 }
1289 
1290 static inline bool pud_user_accessible_page(struct mm_struct *mm, unsigned long addr, pud_t pud)
1291 {
1292 	return pud_valid(pud) && !pud_table(pud) && (pud_user(pud) || pud_user_exec(pud));
1293 }
1294 #endif
1295 
1296 /*
1297  * Atomic pte/pmd modifications.
1298  */
1299 
1300 static inline void __pte_clear(struct mm_struct *mm,
1301 			       unsigned long addr, pte_t *ptep)
1302 {
1303 	__set_pte(ptep, __pte(0));
1304 }
1305 
1306 static inline bool __ptep_test_and_clear_young(struct vm_area_struct *vma,
1307 		unsigned long address, pte_t *ptep)
1308 {
1309 	pte_t old_pte, pte;
1310 
1311 	pte = __ptep_get(ptep);
1312 	do {
1313 		old_pte = pte;
1314 		pte = pte_mkold(pte);
1315 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1316 					       pte_val(old_pte), pte_val(pte));
1317 	} while (pte_val(pte) != pte_val(old_pte));
1318 
1319 	return pte_young(pte);
1320 }
1321 
1322 static inline bool __ptep_clear_flush_young(struct vm_area_struct *vma,
1323 		unsigned long address, pte_t *ptep)
1324 {
1325 	bool young = __ptep_test_and_clear_young(vma, address, ptep);
1326 
1327 	if (young) {
1328 		/*
1329 		 * We can elide the trailing DSB here since the worst that can
1330 		 * happen is that a CPU continues to use the young entry in its
1331 		 * TLB and we mistakenly reclaim the associated page. The
1332 		 * window for such an event is bounded by the next
1333 		 * context-switch, which provides a DSB to complete the TLB
1334 		 * invalidation.
1335 		 */
1336 		__flush_tlb_page(vma, address, TLBF_NOSYNC);
1337 	}
1338 
1339 	return young;
1340 }
1341 
1342 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
1343 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1344 static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
1345 		unsigned long address, pmd_t *pmdp)
1346 {
1347 	/* Operation applies to PMD table entry only if FEAT_HAFT is enabled */
1348 	VM_WARN_ON(pmd_table(READ_ONCE(*pmdp)) && !system_supports_haft());
1349 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
1350 }
1351 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */
1352 
1353 static inline pte_t __ptep_get_and_clear_anysz(struct mm_struct *mm,
1354 					       unsigned long address,
1355 					       pte_t *ptep,
1356 					       unsigned long pgsize)
1357 {
1358 	pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
1359 
1360 	switch (pgsize) {
1361 	case PAGE_SIZE:
1362 		page_table_check_pte_clear(mm, address, pte);
1363 		break;
1364 	case PMD_SIZE:
1365 		page_table_check_pmd_clear(mm, address, pte_pmd(pte));
1366 		break;
1367 #ifndef __PAGETABLE_PMD_FOLDED
1368 	case PUD_SIZE:
1369 		page_table_check_pud_clear(mm, address, pte_pud(pte));
1370 		break;
1371 #endif
1372 	default:
1373 		VM_WARN_ON(1);
1374 	}
1375 
1376 	return pte;
1377 }
1378 
1379 static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
1380 				       unsigned long address, pte_t *ptep)
1381 {
1382 	return __ptep_get_and_clear_anysz(mm, address, ptep, PAGE_SIZE);
1383 }
1384 
1385 static inline void __clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1386 				pte_t *ptep, unsigned int nr, int full)
1387 {
1388 	for (;;) {
1389 		__ptep_get_and_clear(mm, addr, ptep);
1390 		if (--nr == 0)
1391 			break;
1392 		ptep++;
1393 		addr += PAGE_SIZE;
1394 	}
1395 }
1396 
1397 static inline pte_t __get_and_clear_full_ptes(struct mm_struct *mm,
1398 				unsigned long addr, pte_t *ptep,
1399 				unsigned int nr, int full)
1400 {
1401 	pte_t pte, tmp_pte;
1402 
1403 	pte = __ptep_get_and_clear(mm, addr, ptep);
1404 	while (--nr) {
1405 		ptep++;
1406 		addr += PAGE_SIZE;
1407 		tmp_pte = __ptep_get_and_clear(mm, addr, ptep);
1408 		if (pte_dirty(tmp_pte))
1409 			pte = pte_mkdirty(pte);
1410 		if (pte_young(tmp_pte))
1411 			pte = pte_mkyoung(pte);
1412 	}
1413 	return pte;
1414 }
1415 
1416 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1417 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1418 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1419 					    unsigned long address, pmd_t *pmdp)
1420 {
1421 	return pte_pmd(__ptep_get_and_clear_anysz(mm, address, (pte_t *)pmdp, PMD_SIZE));
1422 }
1423 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1424 
1425 static inline void ___ptep_set_wrprotect(struct mm_struct *mm,
1426 					unsigned long address, pte_t *ptep,
1427 					pte_t pte)
1428 {
1429 	pte_t old_pte;
1430 
1431 	do {
1432 		old_pte = pte;
1433 		pte = pte_wrprotect(pte);
1434 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1435 					       pte_val(old_pte), pte_val(pte));
1436 	} while (pte_val(pte) != pte_val(old_pte));
1437 }
1438 
1439 /*
1440  * __ptep_set_wrprotect - mark read-only while transferring potential hardware
1441  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
1442  */
1443 static inline void __ptep_set_wrprotect(struct mm_struct *mm,
1444 					unsigned long address, pte_t *ptep)
1445 {
1446 	___ptep_set_wrprotect(mm, address, ptep, __ptep_get(ptep));
1447 }
1448 
1449 static inline void __wrprotect_ptes(struct mm_struct *mm, unsigned long address,
1450 				pte_t *ptep, unsigned int nr)
1451 {
1452 	unsigned int i;
1453 
1454 	for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++)
1455 		__ptep_set_wrprotect(mm, address, ptep);
1456 }
1457 
1458 static inline void __clear_young_dirty_pte(struct vm_area_struct *vma,
1459 					   unsigned long addr, pte_t *ptep,
1460 					   pte_t pte, cydp_t flags)
1461 {
1462 	pte_t old_pte;
1463 
1464 	do {
1465 		old_pte = pte;
1466 
1467 		if (flags & CYDP_CLEAR_YOUNG)
1468 			pte = pte_mkold(pte);
1469 		if (flags & CYDP_CLEAR_DIRTY)
1470 			pte = pte_mkclean(pte);
1471 
1472 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1473 					       pte_val(old_pte), pte_val(pte));
1474 	} while (pte_val(pte) != pte_val(old_pte));
1475 }
1476 
1477 static inline void __clear_young_dirty_ptes(struct vm_area_struct *vma,
1478 					    unsigned long addr, pte_t *ptep,
1479 					    unsigned int nr, cydp_t flags)
1480 {
1481 	pte_t pte;
1482 
1483 	for (;;) {
1484 		pte = __ptep_get(ptep);
1485 
1486 		if (flags == (CYDP_CLEAR_YOUNG | CYDP_CLEAR_DIRTY))
1487 			__set_pte(ptep, pte_mkclean(pte_mkold(pte)));
1488 		else
1489 			__clear_young_dirty_pte(vma, addr, ptep, pte, flags);
1490 
1491 		if (--nr == 0)
1492 			break;
1493 		ptep++;
1494 		addr += PAGE_SIZE;
1495 	}
1496 }
1497 
1498 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1499 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1500 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1501 				      unsigned long address, pmd_t *pmdp)
1502 {
1503 	__ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
1504 }
1505 
1506 #define pmdp_establish pmdp_establish
1507 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1508 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1509 {
1510 	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
1511 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
1512 }
1513 #endif
1514 
1515 /*
1516  * Encode and decode a swap entry:
1517  *	bits 0-1:	present (must be zero)
1518  *	bits 2:		remember PG_anon_exclusive
1519  *	bit  3:		remember uffd state
1520  *	bits 6-10:	swap type
1521  *	bit  11:	PTE_PRESENT_INVALID (must be zero)
1522  *	bits 12-61:	swap offset
1523  */
1524 #define __SWP_TYPE_SHIFT	6
1525 #define __SWP_TYPE_BITS		5
1526 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
1527 #define __SWP_OFFSET_SHIFT	12
1528 #define __SWP_OFFSET_BITS	50
1529 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
1530 
1531 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
1532 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
1533 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
1534 
1535 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1536 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
1537 
1538 #ifdef CONFIG_ARCH_HAS_PMD_SOFTLEAVES
1539 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
1540 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
1541 #endif /* CONFIG_ARCH_HAS_PMD_SOFTLEAVES */
1542 
1543 /*
1544  * Ensure that there are not more swap files than can be encoded in the kernel
1545  * PTEs.
1546  */
1547 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
1548 
1549 #ifdef CONFIG_ARM64_MTE
1550 
1551 #define __HAVE_ARCH_PREPARE_TO_SWAP
1552 extern int arch_prepare_to_swap(struct folio *folio);
1553 
1554 #define __HAVE_ARCH_SWAP_INVALIDATE
1555 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
1556 {
1557 	if (system_supports_mte())
1558 		mte_invalidate_tags(type, offset);
1559 }
1560 
1561 static inline void arch_swap_invalidate_area(int type)
1562 {
1563 	if (system_supports_mte())
1564 		mte_invalidate_tags_area(type);
1565 }
1566 
1567 #define __HAVE_ARCH_SWAP_RESTORE
1568 extern void arch_swap_restore(swp_entry_t entry, struct folio *folio);
1569 
1570 #endif /* CONFIG_ARM64_MTE */
1571 
1572 /*
1573  * On AArch64, the cache coherency is handled via the __set_ptes() function.
1574  */
1575 static inline void update_mmu_cache_range(struct vm_fault *vmf,
1576 		struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
1577 		unsigned int nr)
1578 {
1579 	/*
1580 	 * We don't do anything here, so there's a very small chance of
1581 	 * us retaking a user fault which we just fixed up. The alternative
1582 	 * is doing a dsb(ishst), but that penalises the fastpath.
1583 	 */
1584 }
1585 
1586 #define update_mmu_cache(vma, addr, ptep) \
1587 	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
1588 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
1589 
1590 #ifdef CONFIG_ARM64_PA_BITS_52
1591 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
1592 #else
1593 #define phys_to_ttbr(addr)	(addr)
1594 #endif
1595 
1596 /*
1597  * On arm64 without hardware Access Flag, copying from user will fail because
1598  * the pte is old and cannot be marked young. So we always end up with zeroed
1599  * page after fork() + CoW for pfn mappings. We don't always have a
1600  * hardware-managed access flag on arm64.
1601  */
1602 #define arch_has_hw_pte_young		cpu_has_hw_af
1603 
1604 #ifdef CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG
1605 #define arch_has_hw_nonleaf_pmd_young	system_supports_haft
1606 #endif
1607 
1608 /*
1609  * Experimentally, it's cheap to set the access flag in hardware and we
1610  * benefit from prefaulting mappings as 'old' to start with.
1611  */
1612 #define arch_wants_old_prefaulted_pte	cpu_has_hw_af
1613 
1614 /*
1615  * Request exec memory is read into pagecache in at least 64K folios. This size
1616  * can be contpte-mapped when 4K base pages are in use (16 pages into 1 iTLB
1617  * entry), and HPA can coalesce it (4 pages into 1 TLB entry) when 16K base
1618  * pages are in use.
1619  */
1620 #define exec_folio_order() ilog2(SZ_64K >> PAGE_SHIFT)
1621 
1622 static inline bool pud_sect_supported(void)
1623 {
1624 	return PAGE_SIZE == SZ_4K;
1625 }
1626 
1627 
1628 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
1629 #define ptep_modify_prot_start ptep_modify_prot_start
1630 extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
1631 				    unsigned long addr, pte_t *ptep);
1632 
1633 #define ptep_modify_prot_commit ptep_modify_prot_commit
1634 extern void ptep_modify_prot_commit(struct vm_area_struct *vma,
1635 				    unsigned long addr, pte_t *ptep,
1636 				    pte_t old_pte, pte_t new_pte);
1637 
1638 #define modify_prot_start_ptes modify_prot_start_ptes
1639 extern pte_t modify_prot_start_ptes(struct vm_area_struct *vma,
1640 				    unsigned long addr, pte_t *ptep,
1641 				    unsigned int nr);
1642 
1643 #define modify_prot_commit_ptes modify_prot_commit_ptes
1644 extern void modify_prot_commit_ptes(struct vm_area_struct *vma, unsigned long addr,
1645 				    pte_t *ptep, pte_t old_pte, pte_t pte,
1646 				    unsigned int nr);
1647 
1648 #ifdef CONFIG_ARM64_CONTPTE
1649 
1650 /*
1651  * The contpte APIs are used to transparently manage the contiguous bit in ptes
1652  * where it is possible and makes sense to do so. The PTE_CONT bit is considered
1653  * a private implementation detail of the public ptep API (see below).
1654  */
1655 extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
1656 				pte_t *ptep, pte_t pte);
1657 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
1658 				pte_t *ptep, pte_t pte);
1659 extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
1660 extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
1661 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
1662 				pte_t *ptep, pte_t pte, unsigned int nr);
1663 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1664 				pte_t *ptep, unsigned int nr, int full);
1665 extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
1666 				unsigned long addr, pte_t *ptep,
1667 				unsigned int nr, int full);
1668 bool contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
1669 				unsigned long addr, pte_t *ptep, unsigned int nr);
1670 bool contpte_clear_flush_young_ptes(struct vm_area_struct *vma,
1671 				unsigned long addr, pte_t *ptep, unsigned int nr);
1672 extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
1673 				pte_t *ptep, unsigned int nr);
1674 extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
1675 				unsigned long addr, pte_t *ptep,
1676 				pte_t entry, int dirty);
1677 extern void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
1678 				unsigned long addr, pte_t *ptep,
1679 				unsigned int nr, cydp_t flags);
1680 
1681 static __always_inline void contpte_try_fold(struct mm_struct *mm,
1682 				unsigned long addr, pte_t *ptep, pte_t pte)
1683 {
1684 	/*
1685 	 * Only bother trying if both the virtual and physical addresses are
1686 	 * aligned and correspond to the last entry in a contig range. The core
1687 	 * code mostly modifies ranges from low to high, so this is the likely
1688 	 * the last modification in the contig range, so a good time to fold.
1689 	 * We can't fold special mappings, because there is no associated folio.
1690 	 */
1691 
1692 	const unsigned long contmask = CONT_PTES - 1;
1693 	bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
1694 
1695 	if (unlikely(valign)) {
1696 		bool palign = (pte_pfn(pte) & contmask) == contmask;
1697 
1698 		if (unlikely(palign &&
1699 		    pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)))
1700 			__contpte_try_fold(mm, addr, ptep, pte);
1701 	}
1702 }
1703 
1704 static __always_inline void contpte_try_unfold(struct mm_struct *mm,
1705 				unsigned long addr, pte_t *ptep, pte_t pte)
1706 {
1707 	if (unlikely(pte_valid_cont(pte)))
1708 		__contpte_try_unfold(mm, addr, ptep, pte);
1709 }
1710 
1711 #define pte_batch_hint pte_batch_hint
1712 static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
1713 {
1714 	if (!pte_valid_cont(pte))
1715 		return 1;
1716 
1717 	return CONT_PTES - (((unsigned long)ptep >> 3) & (CONT_PTES - 1));
1718 }
1719 
1720 /*
1721  * The below functions constitute the public API that arm64 presents to the
1722  * core-mm to manipulate PTE entries within their page tables (or at least this
1723  * is the subset of the API that arm64 needs to implement). These public
1724  * versions will automatically and transparently apply the contiguous bit where
1725  * it makes sense to do so. Therefore any users that are contig-aware (e.g.
1726  * hugetlb, kernel mapper) should NOT use these APIs, but instead use the
1727  * private versions, which are prefixed with double underscore. All of these
1728  * APIs except for ptep_get_lockless() are expected to be called with the PTL
1729  * held. Although the contiguous bit is considered private to the
1730  * implementation, it is deliberately allowed to leak through the getters (e.g.
1731  * ptep_get()), back to core code. This is required so that pte_leaf_size() can
1732  * provide an accurate size for perf_get_pgtable_size(). But this leakage means
1733  * its possible a pte will be passed to a setter with the contiguous bit set, so
1734  * we explicitly clear the contiguous bit in those cases to prevent accidentally
1735  * setting it in the pgtable.
1736  */
1737 
1738 #define ptep_get ptep_get
1739 static inline pte_t ptep_get(pte_t *ptep)
1740 {
1741 	pte_t pte = __ptep_get(ptep);
1742 
1743 	if (likely(!pte_valid_cont(pte)))
1744 		return pte;
1745 
1746 	return contpte_ptep_get(ptep, pte);
1747 }
1748 
1749 #define ptep_get_lockless ptep_get_lockless
1750 static inline pte_t ptep_get_lockless(pte_t *ptep)
1751 {
1752 	pte_t pte = __ptep_get(ptep);
1753 
1754 	if (likely(!pte_valid_cont(pte)))
1755 		return pte;
1756 
1757 	return contpte_ptep_get_lockless(ptep);
1758 }
1759 
1760 static inline void set_pte(pte_t *ptep, pte_t pte)
1761 {
1762 	/*
1763 	 * We don't have the mm or vaddr so cannot unfold contig entries (since
1764 	 * it requires tlb maintenance). set_pte() is not used in core code, so
1765 	 * this should never even be called. Regardless do our best to service
1766 	 * any call and emit a warning if there is any attempt to set a pte on
1767 	 * top of an existing contig range.
1768 	 */
1769 	pte_t orig_pte = __ptep_get(ptep);
1770 
1771 	WARN_ON_ONCE(pte_valid_cont(orig_pte));
1772 	__set_pte(ptep, pte_mknoncont(pte));
1773 }
1774 
1775 #define set_ptes set_ptes
1776 static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
1777 				pte_t *ptep, pte_t pte, unsigned int nr)
1778 {
1779 	pte = pte_mknoncont(pte);
1780 
1781 	if (likely(nr == 1)) {
1782 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1783 		__set_ptes(mm, addr, ptep, pte, 1);
1784 		contpte_try_fold(mm, addr, ptep, pte);
1785 	} else {
1786 		contpte_set_ptes(mm, addr, ptep, pte, nr);
1787 	}
1788 }
1789 
1790 static inline void pte_clear(struct mm_struct *mm,
1791 				unsigned long addr, pte_t *ptep)
1792 {
1793 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1794 	__pte_clear(mm, addr, ptep);
1795 }
1796 
1797 #define clear_full_ptes clear_full_ptes
1798 static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1799 				pte_t *ptep, unsigned int nr, int full)
1800 {
1801 	if (likely(nr == 1)) {
1802 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1803 		__clear_full_ptes(mm, addr, ptep, nr, full);
1804 	} else {
1805 		contpte_clear_full_ptes(mm, addr, ptep, nr, full);
1806 	}
1807 }
1808 
1809 #define get_and_clear_full_ptes get_and_clear_full_ptes
1810 static inline pte_t get_and_clear_full_ptes(struct mm_struct *mm,
1811 				unsigned long addr, pte_t *ptep,
1812 				unsigned int nr, int full)
1813 {
1814 	pte_t pte;
1815 
1816 	if (likely(nr == 1)) {
1817 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1818 		pte = __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1819 	} else {
1820 		pte = contpte_get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1821 	}
1822 
1823 	return pte;
1824 }
1825 
1826 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1827 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
1828 				unsigned long addr, pte_t *ptep)
1829 {
1830 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1831 	return __ptep_get_and_clear(mm, addr, ptep);
1832 }
1833 
1834 static inline bool ptep_try_set(pte_t *ptep, pte_t new_pte)
1835 {
1836 	pteval_t old = 0;
1837 
1838 	if (!try_cmpxchg(&pte_val(*ptep), &old, pte_val(new_pte)))
1839 		return false;
1840 
1841 	/*
1842 	 * The store must be complete by the time this returns, but the caller
1843 	 * may be in lazy MMU mode, where __set_pte_complete() would defer the
1844 	 * barriers. Issue them directly.
1845 	 */
1846 	emit_pte_barriers();
1847 	return true;
1848 }
1849 #define ptep_try_set ptep_try_set
1850 
1851 /*
1852  * arm64 mandates break-before-make: a cleared kernel PTE must have its TLB
1853  * invalidated before a different page is installed in its place. The broadcast
1854  * TLBI is an instruction, not an IPI, so this is safe with interrupts disabled.
1855  */
1856 static inline void flush_tlb_before_set(unsigned long addr)
1857 {
1858 	flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
1859 }
1860 #define flush_tlb_before_set flush_tlb_before_set
1861 
1862 #define test_and_clear_young_ptes test_and_clear_young_ptes
1863 static inline bool test_and_clear_young_ptes(struct vm_area_struct *vma,
1864 		unsigned long addr, pte_t *ptep, unsigned int nr)
1865 {
1866 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1867 		return __ptep_test_and_clear_young(vma, addr, ptep);
1868 
1869 	return contpte_test_and_clear_young_ptes(vma, addr, ptep, nr);
1870 }
1871 
1872 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1873 static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
1874 		unsigned long addr, pte_t *ptep)
1875 {
1876 	return test_and_clear_young_ptes(vma, addr, ptep, 1);
1877 }
1878 
1879 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1880 static inline bool ptep_clear_flush_young(struct vm_area_struct *vma,
1881 		unsigned long addr, pte_t *ptep)
1882 {
1883 	pte_t orig_pte = __ptep_get(ptep);
1884 
1885 	if (likely(!pte_valid_cont(orig_pte)))
1886 		return __ptep_clear_flush_young(vma, addr, ptep);
1887 
1888 	return contpte_clear_flush_young_ptes(vma, addr, ptep, 1);
1889 }
1890 
1891 #define clear_flush_young_ptes clear_flush_young_ptes
1892 static inline bool clear_flush_young_ptes(struct vm_area_struct *vma,
1893 		unsigned long addr, pte_t *ptep, unsigned int nr)
1894 {
1895 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1896 		return __ptep_clear_flush_young(vma, addr, ptep);
1897 
1898 	return contpte_clear_flush_young_ptes(vma, addr, ptep, nr);
1899 }
1900 
1901 #define wrprotect_ptes wrprotect_ptes
1902 static __always_inline void wrprotect_ptes(struct mm_struct *mm,
1903 				unsigned long addr, pte_t *ptep, unsigned int nr)
1904 {
1905 	if (likely(nr == 1)) {
1906 		/*
1907 		 * Optimization: wrprotect_ptes() can only be called for present
1908 		 * ptes so we only need to check contig bit as condition for
1909 		 * unfold, and we can remove the contig bit from the pte we read
1910 		 * to avoid re-reading. This speeds up fork() which is sensitive
1911 		 * for order-0 folios. Equivalent to contpte_try_unfold().
1912 		 */
1913 		pte_t orig_pte = __ptep_get(ptep);
1914 
1915 		if (unlikely(pte_cont(orig_pte))) {
1916 			__contpte_try_unfold(mm, addr, ptep, orig_pte);
1917 			orig_pte = pte_mknoncont(orig_pte);
1918 		}
1919 		___ptep_set_wrprotect(mm, addr, ptep, orig_pte);
1920 	} else {
1921 		contpte_wrprotect_ptes(mm, addr, ptep, nr);
1922 	}
1923 }
1924 
1925 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1926 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1927 				unsigned long addr, pte_t *ptep)
1928 {
1929 	wrprotect_ptes(mm, addr, ptep, 1);
1930 }
1931 
1932 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1933 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
1934 				unsigned long addr, pte_t *ptep,
1935 				pte_t entry, int dirty)
1936 {
1937 	pte_t orig_pte = __ptep_get(ptep);
1938 
1939 	entry = pte_mknoncont(entry);
1940 
1941 	if (likely(!pte_valid_cont(orig_pte)))
1942 		return __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1943 
1944 	return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1945 }
1946 
1947 #define clear_young_dirty_ptes clear_young_dirty_ptes
1948 static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
1949 					  unsigned long addr, pte_t *ptep,
1950 					  unsigned int nr, cydp_t flags)
1951 {
1952 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1953 		__clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1954 	else
1955 		contpte_clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1956 }
1957 
1958 #else /* CONFIG_ARM64_CONTPTE */
1959 
1960 #define ptep_get				__ptep_get
1961 #define set_pte					__set_pte
1962 #define set_ptes				__set_ptes
1963 #define pte_clear				__pte_clear
1964 #define clear_full_ptes				__clear_full_ptes
1965 #define get_and_clear_full_ptes			__get_and_clear_full_ptes
1966 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1967 #define ptep_get_and_clear			__ptep_get_and_clear
1968 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1969 #define ptep_test_and_clear_young		__ptep_test_and_clear_young
1970 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1971 #define ptep_clear_flush_young			__ptep_clear_flush_young
1972 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1973 #define ptep_set_wrprotect			__ptep_set_wrprotect
1974 #define wrprotect_ptes				__wrprotect_ptes
1975 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1976 #define ptep_set_access_flags			__ptep_set_access_flags
1977 #define clear_young_dirty_ptes			__clear_young_dirty_ptes
1978 
1979 #endif /* CONFIG_ARM64_CONTPTE */
1980 
1981 #endif /* !__ASSEMBLER__ */
1982 
1983 #endif /* __ASM_PGTABLE_H */
1984