xref: /linux/arch/arm64/include/asm/pgtable.h (revision 85cdaca6970028bf6f544c355c90035586836ddf)
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_wp(pte_t pte)
349 {
350 	return !!(pte_val(pte) & PTE_UFFD_WP);
351 }
352 
353 static inline pte_t pte_mkuffd_wp(pte_t pte)
354 {
355 	return pte_wrprotect(set_pte_bit(pte, __pgprot(PTE_UFFD_WP)));
356 }
357 
358 static inline pte_t pte_clear_uffd_wp(pte_t pte)
359 {
360 	return clear_pte_bit(pte, __pgprot(PTE_UFFD_WP));
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_wp(pte_t pte)
545 {
546 	return set_pte_bit(pte, __pgprot(PTE_SWP_UFFD_WP));
547 }
548 
549 static inline int pte_swp_uffd_wp(pte_t pte)
550 {
551 	return !!(pte_val(pte) & PTE_SWP_UFFD_WP);
552 }
553 
554 static inline pte_t pte_swp_clear_uffd_wp(pte_t pte)
555 {
556 	return clear_pte_bit(pte, __pgprot(PTE_SWP_UFFD_WP));
557 }
558 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
559 
560 #ifdef CONFIG_NUMA_BALANCING
561 /*
562  * See the comment in include/linux/pgtable.h
563  */
564 static inline int pte_protnone(pte_t pte)
565 {
566 	/*
567 	 * pte_present_invalid() tells us that the pte is invalid from HW
568 	 * perspective but present from SW perspective, so the fields are to be
569 	 * interpreted as per the HW layout. The second 2 checks are the unique
570 	 * encoding that we use for PROT_NONE. It is insufficient to only use
571 	 * the first check because we share the same encoding scheme with pmds
572 	 * which support pmd_mkinvalid(), so can be present-invalid without
573 	 * being PROT_NONE.
574 	 */
575 	return pte_present_invalid(pte) && !pte_user(pte) && !pte_user_exec(pte);
576 }
577 
578 static inline int pmd_protnone(pmd_t pmd)
579 {
580 	return pte_protnone(pmd_pte(pmd));
581 }
582 #endif
583 
584 #define pmd_present(pmd)	pte_present(pmd_pte(pmd))
585 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
586 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
587 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
588 #define pmd_user(pmd)		pte_user(pmd_pte(pmd))
589 #define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
590 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
591 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
592 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
593 #define pmd_mkwrite_novma(pmd)	pte_pmd(pte_mkwrite_novma(pmd_pte(pmd)))
594 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
595 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
596 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
597 #define pmd_mkvalid_k(pmd)	pte_pmd(pte_mkvalid_k(pmd_pte(pmd)))
598 #define pmd_mkinvalid(pmd)	pte_pmd(pte_mkinvalid(pmd_pte(pmd)))
599 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
600 #define pmd_uffd_wp(pmd)	pte_uffd_wp(pmd_pte(pmd))
601 #define pmd_mkuffd_wp(pmd)	pte_pmd(pte_mkuffd_wp(pmd_pte(pmd)))
602 #define pmd_clear_uffd_wp(pmd)	pte_pmd(pte_clear_uffd_wp(pmd_pte(pmd)))
603 #define pmd_swp_uffd_wp(pmd)	pte_swp_uffd_wp(pmd_pte(pmd))
604 #define pmd_swp_mkuffd_wp(pmd)	pte_pmd(pte_swp_mkuffd_wp(pmd_pte(pmd)))
605 #define pmd_swp_clear_uffd_wp(pmd) \
606 				pte_pmd(pte_swp_clear_uffd_wp(pmd_pte(pmd)))
607 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
608 
609 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
610 
611 static inline pmd_t pmd_mkhuge(pmd_t pmd)
612 {
613 	/*
614 	 * It's possible that the pmd is present-invalid on entry
615 	 * and in that case it needs to remain present-invalid on
616 	 * exit. So ensure the VALID bit does not get modified.
617 	 */
618 	pmdval_t mask = PMD_TYPE_MASK & ~PTE_VALID;
619 	pmdval_t val = PMD_TYPE_SECT & ~PTE_VALID;
620 
621 	return __pmd((pmd_val(pmd) & ~mask) | val);
622 }
623 
624 #ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP
625 #define pmd_special(pte)	(!!((pmd_val(pte) & PTE_SPECIAL)))
626 static inline pmd_t pmd_mkspecial(pmd_t pmd)
627 {
628 	return set_pmd_bit(pmd, __pgprot(PTE_SPECIAL));
629 }
630 #endif
631 
632 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
633 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
634 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
635 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
636 
637 #define pud_young(pud)		pte_young(pud_pte(pud))
638 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
639 #define pud_mkwrite_novma(pud)	pte_pud(pte_mkwrite_novma(pud_pte(pud)))
640 #define pud_mkvalid_k(pud)	pte_pud(pte_mkvalid_k(pud_pte(pud)))
641 #define pud_write(pud)		pte_write(pud_pte(pud))
642 
643 static inline pud_t pud_mkhuge(pud_t pud)
644 {
645 	/*
646 	 * It's possible that the pud is present-invalid on entry
647 	 * and in that case it needs to remain present-invalid on
648 	 * exit. So ensure the VALID bit does not get modified.
649 	 */
650 	pudval_t mask = PUD_TYPE_MASK & ~PTE_VALID;
651 	pudval_t val = PUD_TYPE_SECT & ~PTE_VALID;
652 
653 	return __pud((pud_val(pud) & ~mask) | val);
654 }
655 
656 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
657 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
658 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
659 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
660 
661 #define pmd_pgprot pmd_pgprot
662 static inline pgprot_t pmd_pgprot(pmd_t pmd)
663 {
664 	unsigned long pfn = pmd_pfn(pmd);
665 
666 	return __pgprot(pmd_val(pfn_pmd(pfn, __pgprot(0))) ^ pmd_val(pmd));
667 }
668 
669 #define pud_pgprot pud_pgprot
670 static inline pgprot_t pud_pgprot(pud_t pud)
671 {
672 	unsigned long pfn = pud_pfn(pud);
673 
674 	return __pgprot(pud_val(pfn_pud(pfn, __pgprot(0))) ^ pud_val(pud));
675 }
676 
677 static inline void __set_ptes_anysz(struct mm_struct *mm, unsigned long addr,
678 				    pte_t *ptep, pte_t pte, unsigned int nr,
679 				    unsigned long pgsize)
680 {
681 	unsigned long stride = pgsize >> PAGE_SHIFT;
682 
683 	switch (pgsize) {
684 	case PAGE_SIZE:
685 		page_table_check_ptes_set(mm, addr, ptep, pte, nr);
686 		break;
687 	case PMD_SIZE:
688 		page_table_check_pmds_set(mm, addr, (pmd_t *)ptep,
689 					  pte_pmd(pte), nr);
690 		break;
691 #ifndef __PAGETABLE_PMD_FOLDED
692 	case PUD_SIZE:
693 		page_table_check_puds_set(mm, addr, (pud_t *)ptep,
694 					  pte_pud(pte), nr);
695 		break;
696 #endif
697 	default:
698 		VM_WARN_ON(1);
699 	}
700 
701 	__sync_cache_and_tags(pte, nr * stride);
702 
703 	for (;;) {
704 		__check_safe_pte_update(mm, ptep, pte);
705 		__set_pte_nosync(ptep, pte);
706 		if (--nr == 0)
707 			break;
708 		ptep++;
709 		pte = pte_advance_pfn(pte, stride);
710 	}
711 
712 	__set_pte_complete(pte);
713 }
714 
715 static inline void __set_ptes(struct mm_struct *mm, unsigned long addr,
716 			      pte_t *ptep, pte_t pte, unsigned int nr)
717 {
718 	__set_ptes_anysz(mm, addr, ptep, pte, nr, PAGE_SIZE);
719 }
720 
721 static inline void __set_pmds(struct mm_struct *mm, unsigned long addr,
722 			      pmd_t *pmdp, pmd_t pmd, unsigned int nr)
723 {
724 	__set_ptes_anysz(mm, addr, (pte_t *)pmdp, pmd_pte(pmd), nr, PMD_SIZE);
725 }
726 #define set_pmd_at(mm, addr, pmdp, pmd) __set_pmds(mm, addr, pmdp, pmd, 1)
727 
728 static inline void __set_puds(struct mm_struct *mm, unsigned long addr,
729 			      pud_t *pudp, pud_t pud, unsigned int nr)
730 {
731 	__set_ptes_anysz(mm, addr, (pte_t *)pudp, pud_pte(pud), nr, PUD_SIZE);
732 }
733 #define set_pud_at(mm, addr, pudp, pud) __set_puds(mm, addr, pudp, pud, 1)
734 
735 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
736 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
737 
738 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
739 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
740 
741 #define __pgprot_modify(prot,mask,bits) \
742 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
743 
744 #define pgprot_nx(prot) \
745 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
746 
747 #define pgprot_decrypted(prot) \
748 	__pgprot_modify(prot, PROT_NS_SHARED, PROT_NS_SHARED)
749 #define pgprot_encrypted(prot) \
750 	__pgprot_modify(prot, PROT_NS_SHARED, 0)
751 
752 /*
753  * Mark the prot value as uncacheable and unbufferable.
754  */
755 #define pgprot_noncached(prot) \
756 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
757 #define pgprot_writecombine(prot) \
758 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
759 #define pgprot_device(prot) \
760 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
761 #define pgprot_tagged(prot) \
762 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
763 #define pgprot_mhp	pgprot_tagged
764 /*
765  * DMA allocations for non-coherent devices use what the Arm architecture calls
766  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
767  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
768  * is intended for MMIO and thus forbids speculation, preserves access size,
769  * requires strict alignment and can also force write responses to come from the
770  * endpoint.
771  */
772 #define pgprot_dmacoherent(prot) \
773 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
774 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
775 
776 #define __HAVE_PHYS_MEM_ACCESS_PROT
777 struct file;
778 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
779 				     unsigned long size, pgprot_t vma_prot);
780 
781 #define pmd_none(pmd)		(!pmd_val(pmd))
782 
783 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
784 				 PMD_TYPE_TABLE)
785 
786 #define pmd_leaf pmd_leaf
787 static inline bool pmd_leaf(pmd_t pmd)
788 {
789 	return pmd_present(pmd) && !pmd_table(pmd);
790 }
791 
792 #define pmd_bad(pmd)		(!pmd_table(pmd))
793 
794 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
795 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
796 
797 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
798 static inline int pmd_trans_huge(pmd_t pmd)
799 {
800 	/*
801 	 * If pmd is present-invalid, pmd_table() won't detect it
802 	 * as a table, so force the valid bit for the comparison.
803 	 */
804 	return pmd_present(pmd) && !pmd_table(__pmd(pmd_val(pmd) | PTE_VALID));
805 }
806 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
807 
808 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
809 static inline bool pud_table(pud_t pud) { return true; }
810 #else
811 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
812 				 PUD_TYPE_TABLE)
813 #endif
814 
815 extern pgd_t swapper_pg_dir[];
816 extern pgd_t idmap_pg_dir[];
817 extern pgd_t tramp_pg_dir[];
818 extern pgd_t reserved_pg_dir[];
819 
820 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
821 
822 static inline bool in_swapper_pgdir(void *addr)
823 {
824 	return ((unsigned long)addr & PAGE_MASK) ==
825 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
826 }
827 
828 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
829 {
830 #ifdef __PAGETABLE_PMD_FOLDED
831 	if (in_swapper_pgdir(pmdp)) {
832 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
833 		return;
834 	}
835 #endif /* __PAGETABLE_PMD_FOLDED */
836 
837 	WRITE_ONCE(*pmdp, pmd);
838 
839 	if (pmd_valid(pmd))
840 		queue_pte_barriers();
841 }
842 
843 static inline void pmd_clear(pmd_t *pmdp)
844 {
845 	set_pmd(pmdp, __pmd(0));
846 }
847 
848 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
849 {
850 	return __pmd_to_phys(pmd);
851 }
852 
853 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
854 {
855 	return (unsigned long)__va(pmd_page_paddr(pmd));
856 }
857 
858 /* Find an entry in the third-level page table. */
859 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
860 
861 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
862 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
863 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
864 
865 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
866 
867 /* use ONLY for statically allocated translation tables */
868 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
869 
870 #if CONFIG_PGTABLE_LEVELS > 2
871 
872 #define pmd_ERROR(e)	\
873 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
874 
875 #define pud_none(pud)		(!pud_val(pud))
876 #define pud_bad(pud)		((pud_val(pud) & PUD_TYPE_MASK) != \
877 				 PUD_TYPE_TABLE)
878 #define pud_present(pud)	pte_present(pud_pte(pud))
879 #ifndef __PAGETABLE_PMD_FOLDED
880 #define pud_leaf pud_leaf
881 static inline bool pud_leaf(pud_t pud)
882 {
883 	return pud_present(pud) && !pud_table(pud);
884 }
885 #else
886 #define pud_leaf(pud)		false
887 #endif
888 #define pud_valid(pud)		pte_valid(pud_pte(pud))
889 #define pud_user(pud)		pte_user(pud_pte(pud))
890 #define pud_user_exec(pud)	pte_user_exec(pud_pte(pud))
891 
892 static inline bool pgtable_l4_enabled(void);
893 
894 static inline void set_pud(pud_t *pudp, pud_t pud)
895 {
896 	if (!pgtable_l4_enabled() && in_swapper_pgdir(pudp)) {
897 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
898 		return;
899 	}
900 
901 	WRITE_ONCE(*pudp, pud);
902 
903 	if (pud_valid(pud))
904 		queue_pte_barriers();
905 }
906 
907 static inline void pud_clear(pud_t *pudp)
908 {
909 	set_pud(pudp, __pud(0));
910 }
911 
912 static inline phys_addr_t pud_page_paddr(pud_t pud)
913 {
914 	return __pud_to_phys(pud);
915 }
916 
917 static inline pmd_t *pud_pgtable(pud_t pud)
918 {
919 	return (pmd_t *)__va(pud_page_paddr(pud));
920 }
921 
922 /* Find an entry in the second-level page table. */
923 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
924 
925 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
926 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
927 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
928 
929 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
930 
931 /* use ONLY for statically allocated translation tables */
932 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
933 
934 #else
935 
936 #define pud_valid(pud)		false
937 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
938 #define pud_user_exec(pud)	pud_user(pud) /* Always 0 with folding */
939 
940 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
941 #define pmd_set_fixmap(addr)		NULL
942 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
943 #define pmd_clear_fixmap()
944 
945 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
946 
947 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
948 
949 #if CONFIG_PGTABLE_LEVELS > 3
950 
951 static __always_inline bool pgtable_l4_enabled(void)
952 {
953 	if (CONFIG_PGTABLE_LEVELS > 4 || !IS_ENABLED(CONFIG_ARM64_LPA2))
954 		return true;
955 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
956 		return vabits_actual == VA_BITS;
957 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
958 }
959 
960 static inline bool mm_pud_folded(const struct mm_struct *mm)
961 {
962 	return !pgtable_l4_enabled();
963 }
964 #define mm_pud_folded  mm_pud_folded
965 
966 #define pud_ERROR(e)	\
967 	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
968 
969 #define p4d_none(p4d)		(pgtable_l4_enabled() && !p4d_val(p4d))
970 #define p4d_bad(p4d)		(pgtable_l4_enabled() && \
971 				((p4d_val(p4d) & P4D_TYPE_MASK) != \
972 				 P4D_TYPE_TABLE))
973 #define p4d_present(p4d)	(!p4d_none(p4d))
974 
975 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
976 {
977 	if (in_swapper_pgdir(p4dp)) {
978 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
979 		return;
980 	}
981 
982 	WRITE_ONCE(*p4dp, p4d);
983 	queue_pte_barriers();
984 }
985 
986 static inline void p4d_clear(p4d_t *p4dp)
987 {
988 	if (pgtable_l4_enabled())
989 		set_p4d(p4dp, __p4d(0));
990 }
991 
992 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
993 {
994 	return __p4d_to_phys(p4d);
995 }
996 
997 #define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
998 
999 static inline pud_t *p4d_to_folded_pud(p4d_t *p4dp, unsigned long addr)
1000 {
1001 	/* Ensure that 'p4dp' indexes a page table according to 'addr' */
1002 	VM_BUG_ON(((addr >> P4D_SHIFT) ^ ((u64)p4dp >> 3)) % PTRS_PER_P4D);
1003 
1004 	return (pud_t *)PTR_ALIGN_DOWN(p4dp, PAGE_SIZE) + pud_index(addr);
1005 }
1006 
1007 static inline pud_t *p4d_pgtable(p4d_t p4d)
1008 {
1009 	return (pud_t *)__va(p4d_page_paddr(p4d));
1010 }
1011 
1012 static inline phys_addr_t pud_offset_phys(p4d_t *p4dp, unsigned long addr)
1013 {
1014 	VM_WARN_ON_ONCE(!pgtable_l4_enabled());
1015 
1016 	return p4d_page_paddr(READ_ONCE(*p4dp)) + pud_index(addr) * sizeof(pud_t);
1017 }
1018 
1019 static inline
1020 pud_t *pud_offset_lockless(p4d_t *p4dp, p4d_t p4d, unsigned long addr)
1021 {
1022 	if (!pgtable_l4_enabled())
1023 		return p4d_to_folded_pud(p4dp, addr);
1024 	return (pud_t *)__va(p4d_page_paddr(p4d)) + pud_index(addr);
1025 }
1026 #define pud_offset_lockless pud_offset_lockless
1027 
1028 static inline pud_t *pud_offset(p4d_t *p4dp, unsigned long addr)
1029 {
1030 	return pud_offset_lockless(p4dp, READ_ONCE(*p4dp), addr);
1031 }
1032 #define pud_offset	pud_offset
1033 
1034 static inline pud_t *pud_set_fixmap(unsigned long addr)
1035 {
1036 	if (!pgtable_l4_enabled())
1037 		return NULL;
1038 	return (pud_t *)set_fixmap_offset(FIX_PUD, addr);
1039 }
1040 
1041 static inline pud_t *pud_set_fixmap_offset(p4d_t *p4dp, unsigned long addr)
1042 {
1043 	if (!pgtable_l4_enabled())
1044 		return p4d_to_folded_pud(p4dp, addr);
1045 	return pud_set_fixmap(pud_offset_phys(p4dp, addr));
1046 }
1047 
1048 static inline void pud_clear_fixmap(void)
1049 {
1050 	if (pgtable_l4_enabled())
1051 		clear_fixmap(FIX_PUD);
1052 }
1053 
1054 /* use ONLY for statically allocated translation tables */
1055 static inline pud_t *pud_offset_kimg(p4d_t *p4dp, u64 addr)
1056 {
1057 	if (!pgtable_l4_enabled())
1058 		return p4d_to_folded_pud(p4dp, addr);
1059 	return (pud_t *)__phys_to_kimg(pud_offset_phys(p4dp, addr));
1060 }
1061 
1062 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
1063 
1064 #else
1065 
1066 static inline bool pgtable_l4_enabled(void) { return false; }
1067 
1068 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
1069 
1070 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
1071 #define pud_set_fixmap(addr)		NULL
1072 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
1073 #define pud_clear_fixmap()
1074 
1075 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
1076 
1077 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
1078 
1079 #if CONFIG_PGTABLE_LEVELS > 4
1080 
1081 static __always_inline bool pgtable_l5_enabled(void)
1082 {
1083 	if (!alternative_has_cap_likely(ARM64_ALWAYS_BOOT))
1084 		return vabits_actual == VA_BITS;
1085 	return alternative_has_cap_unlikely(ARM64_HAS_VA52);
1086 }
1087 
1088 static inline bool mm_p4d_folded(const struct mm_struct *mm)
1089 {
1090 	return !pgtable_l5_enabled();
1091 }
1092 #define mm_p4d_folded  mm_p4d_folded
1093 
1094 #define p4d_ERROR(e)	\
1095 	pr_err("%s:%d: bad p4d %016llx.\n", __FILE__, __LINE__, p4d_val(e))
1096 
1097 #define pgd_none(pgd)		(pgtable_l5_enabled() && !pgd_val(pgd))
1098 #define pgd_bad(pgd)		(pgtable_l5_enabled() && \
1099 				((pgd_val(pgd) & PGD_TYPE_MASK) != \
1100 				 PGD_TYPE_TABLE))
1101 #define pgd_present(pgd)	(!pgd_none(pgd))
1102 
1103 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
1104 {
1105 	if (in_swapper_pgdir(pgdp)) {
1106 		set_swapper_pgd(pgdp, __pgd(pgd_val(pgd)));
1107 		return;
1108 	}
1109 
1110 	WRITE_ONCE(*pgdp, pgd);
1111 	queue_pte_barriers();
1112 }
1113 
1114 static inline void pgd_clear(pgd_t *pgdp)
1115 {
1116 	if (pgtable_l5_enabled())
1117 		set_pgd(pgdp, __pgd(0));
1118 }
1119 
1120 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
1121 {
1122 	return __pgd_to_phys(pgd);
1123 }
1124 
1125 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1126 
1127 static inline p4d_t *pgd_to_folded_p4d(pgd_t *pgdp, unsigned long addr)
1128 {
1129 	/* Ensure that 'pgdp' indexes a page table according to 'addr' */
1130 	VM_BUG_ON(((addr >> PGDIR_SHIFT) ^ ((u64)pgdp >> 3)) % PTRS_PER_PGD);
1131 
1132 	return (p4d_t *)PTR_ALIGN_DOWN(pgdp, PAGE_SIZE) + p4d_index(addr);
1133 }
1134 
1135 static inline phys_addr_t p4d_offset_phys(pgd_t *pgdp, unsigned long addr)
1136 {
1137 	VM_WARN_ON_ONCE(!pgtable_l5_enabled());
1138 
1139 	return pgd_page_paddr(READ_ONCE(*pgdp)) + p4d_index(addr) * sizeof(p4d_t);
1140 }
1141 
1142 static inline
1143 p4d_t *p4d_offset_lockless(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1144 {
1145 	if (!pgtable_l5_enabled())
1146 		return pgd_to_folded_p4d(pgdp, addr);
1147 	return (p4d_t *)__va(pgd_page_paddr(pgd)) + p4d_index(addr);
1148 }
1149 #define p4d_offset_lockless p4d_offset_lockless
1150 
1151 static inline p4d_t *p4d_offset(pgd_t *pgdp, unsigned long addr)
1152 {
1153 	return p4d_offset_lockless(pgdp, READ_ONCE(*pgdp), addr);
1154 }
1155 
1156 static inline p4d_t *p4d_set_fixmap(unsigned long addr)
1157 {
1158 	if (!pgtable_l5_enabled())
1159 		return NULL;
1160 	return (p4d_t *)set_fixmap_offset(FIX_P4D, addr);
1161 }
1162 
1163 static inline p4d_t *p4d_set_fixmap_offset(pgd_t *pgdp, unsigned long addr)
1164 {
1165 	if (!pgtable_l5_enabled())
1166 		return pgd_to_folded_p4d(pgdp, addr);
1167 	return p4d_set_fixmap(p4d_offset_phys(pgdp, addr));
1168 }
1169 
1170 static inline void p4d_clear_fixmap(void)
1171 {
1172 	if (pgtable_l5_enabled())
1173 		clear_fixmap(FIX_P4D);
1174 }
1175 
1176 /* use ONLY for statically allocated translation tables */
1177 static inline p4d_t *p4d_offset_kimg(pgd_t *pgdp, u64 addr)
1178 {
1179 	if (!pgtable_l5_enabled())
1180 		return pgd_to_folded_p4d(pgdp, addr);
1181 	return (p4d_t *)__phys_to_kimg(p4d_offset_phys(pgdp, addr));
1182 }
1183 
1184 #define pgd_page(pgd)		pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
1185 
1186 #else
1187 
1188 static inline bool pgtable_l5_enabled(void) { return false; }
1189 
1190 #define p4d_index(addr)		(((addr) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
1191 
1192 /* Match p4d_offset folding in <asm/generic/pgtable-nop4d.h> */
1193 #define p4d_set_fixmap(addr)		NULL
1194 #define p4d_set_fixmap_offset(p4dp, addr)	((p4d_t *)p4dp)
1195 #define p4d_clear_fixmap()
1196 
1197 #define p4d_offset_kimg(dir,addr)	((p4d_t *)dir)
1198 
1199 static inline
1200 p4d_t *p4d_offset_lockless_folded(pgd_t *pgdp, pgd_t pgd, unsigned long addr)
1201 {
1202 	/*
1203 	 * With runtime folding of the pud, pud_offset_lockless() passes
1204 	 * the 'pgd_t *' we return here to p4d_to_folded_pud(), which
1205 	 * will offset the pointer assuming that it points into
1206 	 * a page-table page. However, the fast GUP path passes us a
1207 	 * pgd_t allocated on the stack and so we must use the original
1208 	 * pointer in 'pgdp' to construct the p4d pointer instead of
1209 	 * using the generic p4d_offset_lockless() implementation.
1210 	 *
1211 	 * Note: reusing the original pointer means that we may
1212 	 * dereference the same (live) page-table entry multiple times.
1213 	 * This is safe because it is still only loaded once in the
1214 	 * context of each level and the CPU guarantees same-address
1215 	 * read-after-read ordering.
1216 	 */
1217 	return p4d_offset(pgdp, addr);
1218 }
1219 #define p4d_offset_lockless p4d_offset_lockless_folded
1220 
1221 #endif  /* CONFIG_PGTABLE_LEVELS > 4 */
1222 
1223 #define pgd_ERROR(e)	\
1224 	pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
1225 
1226 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
1227 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
1228 
1229 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
1230 {
1231 	/*
1232 	 * Normal and Normal-Tagged are two different memory types and indices
1233 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
1234 	 */
1235 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
1236 			      PTE_PRESENT_INVALID | PTE_VALID | PTE_WRITE |
1237 			      PTE_GP | PTE_ATTRINDX_MASK | PTE_PO_IDX_MASK;
1238 
1239 	/* preserve the hardware dirty information */
1240 	if (pte_hw_dirty(pte))
1241 		pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
1242 
1243 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
1244 	/*
1245 	 * If we end up clearing hw dirtiness for a sw-dirty PTE, set hardware
1246 	 * dirtiness again.
1247 	 */
1248 	if (pte_sw_dirty(pte))
1249 		pte = pte_mkdirty(pte);
1250 	return pte;
1251 }
1252 
1253 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
1254 {
1255 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
1256 }
1257 
1258 extern int __ptep_set_access_flags_anysz(struct vm_area_struct *vma,
1259 					 unsigned long address, pte_t *ptep,
1260 					 pte_t entry, int dirty,
1261 					 unsigned long pgsize);
1262 
1263 static inline int __ptep_set_access_flags(struct vm_area_struct *vma,
1264 					  unsigned long address, pte_t *ptep,
1265 					  pte_t entry, int dirty)
1266 {
1267 	return __ptep_set_access_flags_anysz(vma, address, ptep, entry, dirty,
1268 					     PAGE_SIZE);
1269 }
1270 
1271 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1272 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1273 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
1274 					unsigned long address, pmd_t *pmdp,
1275 					pmd_t entry, int dirty)
1276 {
1277 	return __ptep_set_access_flags_anysz(vma, address, (pte_t *)pmdp,
1278 					     pmd_pte(entry), dirty, PMD_SIZE);
1279 }
1280 #endif
1281 
1282 #ifdef CONFIG_PAGE_TABLE_CHECK
1283 static inline bool pte_user_accessible_page(struct mm_struct *mm, unsigned long addr, pte_t pte)
1284 {
1285 	return pte_valid(pte) && (pte_user(pte) || pte_user_exec(pte));
1286 }
1287 
1288 static inline bool pmd_user_accessible_page(struct mm_struct *mm, unsigned long addr, pmd_t pmd)
1289 {
1290 	return pmd_valid(pmd) && !pmd_table(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
1291 }
1292 
1293 static inline bool pud_user_accessible_page(struct mm_struct *mm, unsigned long addr, pud_t pud)
1294 {
1295 	return pud_valid(pud) && !pud_table(pud) && (pud_user(pud) || pud_user_exec(pud));
1296 }
1297 #endif
1298 
1299 /*
1300  * Atomic pte/pmd modifications.
1301  */
1302 
1303 static inline void __pte_clear(struct mm_struct *mm,
1304 			       unsigned long addr, pte_t *ptep)
1305 {
1306 	__set_pte(ptep, __pte(0));
1307 }
1308 
1309 static inline bool __ptep_test_and_clear_young(struct vm_area_struct *vma,
1310 		unsigned long address, pte_t *ptep)
1311 {
1312 	pte_t old_pte, pte;
1313 
1314 	pte = __ptep_get(ptep);
1315 	do {
1316 		old_pte = pte;
1317 		pte = pte_mkold(pte);
1318 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1319 					       pte_val(old_pte), pte_val(pte));
1320 	} while (pte_val(pte) != pte_val(old_pte));
1321 
1322 	return pte_young(pte);
1323 }
1324 
1325 static inline bool __ptep_clear_flush_young(struct vm_area_struct *vma,
1326 		unsigned long address, pte_t *ptep)
1327 {
1328 	bool young = __ptep_test_and_clear_young(vma, address, ptep);
1329 
1330 	if (young) {
1331 		/*
1332 		 * We can elide the trailing DSB here since the worst that can
1333 		 * happen is that a CPU continues to use the young entry in its
1334 		 * TLB and we mistakenly reclaim the associated page. The
1335 		 * window for such an event is bounded by the next
1336 		 * context-switch, which provides a DSB to complete the TLB
1337 		 * invalidation.
1338 		 */
1339 		__flush_tlb_page(vma, address, TLBF_NOSYNC);
1340 	}
1341 
1342 	return young;
1343 }
1344 
1345 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG)
1346 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1347 static inline bool pmdp_test_and_clear_young(struct vm_area_struct *vma,
1348 		unsigned long address, pmd_t *pmdp)
1349 {
1350 	/* Operation applies to PMD table entry only if FEAT_HAFT is enabled */
1351 	VM_WARN_ON(pmd_table(READ_ONCE(*pmdp)) && !system_supports_haft());
1352 	return __ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
1353 }
1354 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG */
1355 
1356 static inline pte_t __ptep_get_and_clear_anysz(struct mm_struct *mm,
1357 					       unsigned long address,
1358 					       pte_t *ptep,
1359 					       unsigned long pgsize)
1360 {
1361 	pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
1362 
1363 	switch (pgsize) {
1364 	case PAGE_SIZE:
1365 		page_table_check_pte_clear(mm, address, pte);
1366 		break;
1367 	case PMD_SIZE:
1368 		page_table_check_pmd_clear(mm, address, pte_pmd(pte));
1369 		break;
1370 #ifndef __PAGETABLE_PMD_FOLDED
1371 	case PUD_SIZE:
1372 		page_table_check_pud_clear(mm, address, pte_pud(pte));
1373 		break;
1374 #endif
1375 	default:
1376 		VM_WARN_ON(1);
1377 	}
1378 
1379 	return pte;
1380 }
1381 
1382 static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
1383 				       unsigned long address, pte_t *ptep)
1384 {
1385 	return __ptep_get_and_clear_anysz(mm, address, ptep, PAGE_SIZE);
1386 }
1387 
1388 static inline void __clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1389 				pte_t *ptep, unsigned int nr, int full)
1390 {
1391 	for (;;) {
1392 		__ptep_get_and_clear(mm, addr, ptep);
1393 		if (--nr == 0)
1394 			break;
1395 		ptep++;
1396 		addr += PAGE_SIZE;
1397 	}
1398 }
1399 
1400 static inline pte_t __get_and_clear_full_ptes(struct mm_struct *mm,
1401 				unsigned long addr, pte_t *ptep,
1402 				unsigned int nr, int full)
1403 {
1404 	pte_t pte, tmp_pte;
1405 
1406 	pte = __ptep_get_and_clear(mm, addr, ptep);
1407 	while (--nr) {
1408 		ptep++;
1409 		addr += PAGE_SIZE;
1410 		tmp_pte = __ptep_get_and_clear(mm, addr, ptep);
1411 		if (pte_dirty(tmp_pte))
1412 			pte = pte_mkdirty(pte);
1413 		if (pte_young(tmp_pte))
1414 			pte = pte_mkyoung(pte);
1415 	}
1416 	return pte;
1417 }
1418 
1419 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1420 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1421 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
1422 					    unsigned long address, pmd_t *pmdp)
1423 {
1424 	return pte_pmd(__ptep_get_and_clear_anysz(mm, address, (pte_t *)pmdp, PMD_SIZE));
1425 }
1426 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1427 
1428 static inline void ___ptep_set_wrprotect(struct mm_struct *mm,
1429 					unsigned long address, pte_t *ptep,
1430 					pte_t pte)
1431 {
1432 	pte_t old_pte;
1433 
1434 	do {
1435 		old_pte = pte;
1436 		pte = pte_wrprotect(pte);
1437 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1438 					       pte_val(old_pte), pte_val(pte));
1439 	} while (pte_val(pte) != pte_val(old_pte));
1440 }
1441 
1442 /*
1443  * __ptep_set_wrprotect - mark read-only while transferring potential hardware
1444  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
1445  */
1446 static inline void __ptep_set_wrprotect(struct mm_struct *mm,
1447 					unsigned long address, pte_t *ptep)
1448 {
1449 	___ptep_set_wrprotect(mm, address, ptep, __ptep_get(ptep));
1450 }
1451 
1452 static inline void __wrprotect_ptes(struct mm_struct *mm, unsigned long address,
1453 				pte_t *ptep, unsigned int nr)
1454 {
1455 	unsigned int i;
1456 
1457 	for (i = 0; i < nr; i++, address += PAGE_SIZE, ptep++)
1458 		__ptep_set_wrprotect(mm, address, ptep);
1459 }
1460 
1461 static inline void __clear_young_dirty_pte(struct vm_area_struct *vma,
1462 					   unsigned long addr, pte_t *ptep,
1463 					   pte_t pte, cydp_t flags)
1464 {
1465 	pte_t old_pte;
1466 
1467 	do {
1468 		old_pte = pte;
1469 
1470 		if (flags & CYDP_CLEAR_YOUNG)
1471 			pte = pte_mkold(pte);
1472 		if (flags & CYDP_CLEAR_DIRTY)
1473 			pte = pte_mkclean(pte);
1474 
1475 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
1476 					       pte_val(old_pte), pte_val(pte));
1477 	} while (pte_val(pte) != pte_val(old_pte));
1478 }
1479 
1480 static inline void __clear_young_dirty_ptes(struct vm_area_struct *vma,
1481 					    unsigned long addr, pte_t *ptep,
1482 					    unsigned int nr, cydp_t flags)
1483 {
1484 	pte_t pte;
1485 
1486 	for (;;) {
1487 		pte = __ptep_get(ptep);
1488 
1489 		if (flags == (CYDP_CLEAR_YOUNG | CYDP_CLEAR_DIRTY))
1490 			__set_pte(ptep, pte_mkclean(pte_mkold(pte)));
1491 		else
1492 			__clear_young_dirty_pte(vma, addr, ptep, pte, flags);
1493 
1494 		if (--nr == 0)
1495 			break;
1496 		ptep++;
1497 		addr += PAGE_SIZE;
1498 	}
1499 }
1500 
1501 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1502 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1503 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1504 				      unsigned long address, pmd_t *pmdp)
1505 {
1506 	__ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
1507 }
1508 
1509 #define pmdp_establish pmdp_establish
1510 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1511 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1512 {
1513 	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
1514 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
1515 }
1516 #endif
1517 
1518 /*
1519  * Encode and decode a swap entry:
1520  *	bits 0-1:	present (must be zero)
1521  *	bits 2:		remember PG_anon_exclusive
1522  *	bit  3:		remember uffd-wp state
1523  *	bits 6-10:	swap type
1524  *	bit  11:	PTE_PRESENT_INVALID (must be zero)
1525  *	bits 12-61:	swap offset
1526  */
1527 #define __SWP_TYPE_SHIFT	6
1528 #define __SWP_TYPE_BITS		5
1529 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
1530 #define __SWP_OFFSET_SHIFT	12
1531 #define __SWP_OFFSET_BITS	50
1532 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
1533 
1534 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
1535 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
1536 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
1537 
1538 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
1539 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
1540 
1541 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1542 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
1543 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
1544 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
1545 
1546 /*
1547  * Ensure that there are not more swap files than can be encoded in the kernel
1548  * PTEs.
1549  */
1550 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
1551 
1552 #ifdef CONFIG_ARM64_MTE
1553 
1554 #define __HAVE_ARCH_PREPARE_TO_SWAP
1555 extern int arch_prepare_to_swap(struct folio *folio);
1556 
1557 #define __HAVE_ARCH_SWAP_INVALIDATE
1558 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
1559 {
1560 	if (system_supports_mte())
1561 		mte_invalidate_tags(type, offset);
1562 }
1563 
1564 static inline void arch_swap_invalidate_area(int type)
1565 {
1566 	if (system_supports_mte())
1567 		mte_invalidate_tags_area(type);
1568 }
1569 
1570 #define __HAVE_ARCH_SWAP_RESTORE
1571 extern void arch_swap_restore(swp_entry_t entry, struct folio *folio);
1572 
1573 #endif /* CONFIG_ARM64_MTE */
1574 
1575 /*
1576  * On AArch64, the cache coherency is handled via the __set_ptes() function.
1577  */
1578 static inline void update_mmu_cache_range(struct vm_fault *vmf,
1579 		struct vm_area_struct *vma, unsigned long addr, pte_t *ptep,
1580 		unsigned int nr)
1581 {
1582 	/*
1583 	 * We don't do anything here, so there's a very small chance of
1584 	 * us retaking a user fault which we just fixed up. The alternative
1585 	 * is doing a dsb(ishst), but that penalises the fastpath.
1586 	 */
1587 }
1588 
1589 #define update_mmu_cache(vma, addr, ptep) \
1590 	update_mmu_cache_range(NULL, vma, addr, ptep, 1)
1591 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
1592 
1593 #ifdef CONFIG_ARM64_PA_BITS_52
1594 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
1595 #else
1596 #define phys_to_ttbr(addr)	(addr)
1597 #endif
1598 
1599 /*
1600  * On arm64 without hardware Access Flag, copying from user will fail because
1601  * the pte is old and cannot be marked young. So we always end up with zeroed
1602  * page after fork() + CoW for pfn mappings. We don't always have a
1603  * hardware-managed access flag on arm64.
1604  */
1605 #define arch_has_hw_pte_young		cpu_has_hw_af
1606 
1607 #ifdef CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG
1608 #define arch_has_hw_nonleaf_pmd_young	system_supports_haft
1609 #endif
1610 
1611 /*
1612  * Experimentally, it's cheap to set the access flag in hardware and we
1613  * benefit from prefaulting mappings as 'old' to start with.
1614  */
1615 #define arch_wants_old_prefaulted_pte	cpu_has_hw_af
1616 
1617 /*
1618  * Request exec memory is read into pagecache in at least 64K folios. This size
1619  * can be contpte-mapped when 4K base pages are in use (16 pages into 1 iTLB
1620  * entry), and HPA can coalesce it (4 pages into 1 TLB entry) when 16K base
1621  * pages are in use.
1622  */
1623 #define exec_folio_order() ilog2(SZ_64K >> PAGE_SHIFT)
1624 
1625 static inline bool pud_sect_supported(void)
1626 {
1627 	return PAGE_SIZE == SZ_4K;
1628 }
1629 
1630 
1631 #define __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
1632 #define ptep_modify_prot_start ptep_modify_prot_start
1633 extern pte_t ptep_modify_prot_start(struct vm_area_struct *vma,
1634 				    unsigned long addr, pte_t *ptep);
1635 
1636 #define ptep_modify_prot_commit ptep_modify_prot_commit
1637 extern void ptep_modify_prot_commit(struct vm_area_struct *vma,
1638 				    unsigned long addr, pte_t *ptep,
1639 				    pte_t old_pte, pte_t new_pte);
1640 
1641 #define modify_prot_start_ptes modify_prot_start_ptes
1642 extern pte_t modify_prot_start_ptes(struct vm_area_struct *vma,
1643 				    unsigned long addr, pte_t *ptep,
1644 				    unsigned int nr);
1645 
1646 #define modify_prot_commit_ptes modify_prot_commit_ptes
1647 extern void modify_prot_commit_ptes(struct vm_area_struct *vma, unsigned long addr,
1648 				    pte_t *ptep, pte_t old_pte, pte_t pte,
1649 				    unsigned int nr);
1650 
1651 #ifdef CONFIG_ARM64_CONTPTE
1652 
1653 /*
1654  * The contpte APIs are used to transparently manage the contiguous bit in ptes
1655  * where it is possible and makes sense to do so. The PTE_CONT bit is considered
1656  * a private implementation detail of the public ptep API (see below).
1657  */
1658 extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
1659 				pte_t *ptep, pte_t pte);
1660 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
1661 				pte_t *ptep, pte_t pte);
1662 extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
1663 extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
1664 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
1665 				pte_t *ptep, pte_t pte, unsigned int nr);
1666 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1667 				pte_t *ptep, unsigned int nr, int full);
1668 extern pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
1669 				unsigned long addr, pte_t *ptep,
1670 				unsigned int nr, int full);
1671 bool contpte_test_and_clear_young_ptes(struct vm_area_struct *vma,
1672 				unsigned long addr, pte_t *ptep, unsigned int nr);
1673 bool contpte_clear_flush_young_ptes(struct vm_area_struct *vma,
1674 				unsigned long addr, pte_t *ptep, unsigned int nr);
1675 extern void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
1676 				pte_t *ptep, unsigned int nr);
1677 extern int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
1678 				unsigned long addr, pte_t *ptep,
1679 				pte_t entry, int dirty);
1680 extern void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma,
1681 				unsigned long addr, pte_t *ptep,
1682 				unsigned int nr, cydp_t flags);
1683 
1684 static __always_inline void contpte_try_fold(struct mm_struct *mm,
1685 				unsigned long addr, pte_t *ptep, pte_t pte)
1686 {
1687 	/*
1688 	 * Only bother trying if both the virtual and physical addresses are
1689 	 * aligned and correspond to the last entry in a contig range. The core
1690 	 * code mostly modifies ranges from low to high, so this is the likely
1691 	 * the last modification in the contig range, so a good time to fold.
1692 	 * We can't fold special mappings, because there is no associated folio.
1693 	 */
1694 
1695 	const unsigned long contmask = CONT_PTES - 1;
1696 	bool valign = ((addr >> PAGE_SHIFT) & contmask) == contmask;
1697 
1698 	if (unlikely(valign)) {
1699 		bool palign = (pte_pfn(pte) & contmask) == contmask;
1700 
1701 		if (unlikely(palign &&
1702 		    pte_valid(pte) && !pte_cont(pte) && !pte_special(pte)))
1703 			__contpte_try_fold(mm, addr, ptep, pte);
1704 	}
1705 }
1706 
1707 static __always_inline void contpte_try_unfold(struct mm_struct *mm,
1708 				unsigned long addr, pte_t *ptep, pte_t pte)
1709 {
1710 	if (unlikely(pte_valid_cont(pte)))
1711 		__contpte_try_unfold(mm, addr, ptep, pte);
1712 }
1713 
1714 #define pte_batch_hint pte_batch_hint
1715 static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
1716 {
1717 	if (!pte_valid_cont(pte))
1718 		return 1;
1719 
1720 	return CONT_PTES - (((unsigned long)ptep >> 3) & (CONT_PTES - 1));
1721 }
1722 
1723 /*
1724  * The below functions constitute the public API that arm64 presents to the
1725  * core-mm to manipulate PTE entries within their page tables (or at least this
1726  * is the subset of the API that arm64 needs to implement). These public
1727  * versions will automatically and transparently apply the contiguous bit where
1728  * it makes sense to do so. Therefore any users that are contig-aware (e.g.
1729  * hugetlb, kernel mapper) should NOT use these APIs, but instead use the
1730  * private versions, which are prefixed with double underscore. All of these
1731  * APIs except for ptep_get_lockless() are expected to be called with the PTL
1732  * held. Although the contiguous bit is considered private to the
1733  * implementation, it is deliberately allowed to leak through the getters (e.g.
1734  * ptep_get()), back to core code. This is required so that pte_leaf_size() can
1735  * provide an accurate size for perf_get_pgtable_size(). But this leakage means
1736  * its possible a pte will be passed to a setter with the contiguous bit set, so
1737  * we explicitly clear the contiguous bit in those cases to prevent accidentally
1738  * setting it in the pgtable.
1739  */
1740 
1741 #define ptep_get ptep_get
1742 static inline pte_t ptep_get(pte_t *ptep)
1743 {
1744 	pte_t pte = __ptep_get(ptep);
1745 
1746 	if (likely(!pte_valid_cont(pte)))
1747 		return pte;
1748 
1749 	return contpte_ptep_get(ptep, pte);
1750 }
1751 
1752 #define ptep_get_lockless ptep_get_lockless
1753 static inline pte_t ptep_get_lockless(pte_t *ptep)
1754 {
1755 	pte_t pte = __ptep_get(ptep);
1756 
1757 	if (likely(!pte_valid_cont(pte)))
1758 		return pte;
1759 
1760 	return contpte_ptep_get_lockless(ptep);
1761 }
1762 
1763 static inline void set_pte(pte_t *ptep, pte_t pte)
1764 {
1765 	/*
1766 	 * We don't have the mm or vaddr so cannot unfold contig entries (since
1767 	 * it requires tlb maintenance). set_pte() is not used in core code, so
1768 	 * this should never even be called. Regardless do our best to service
1769 	 * any call and emit a warning if there is any attempt to set a pte on
1770 	 * top of an existing contig range.
1771 	 */
1772 	pte_t orig_pte = __ptep_get(ptep);
1773 
1774 	WARN_ON_ONCE(pte_valid_cont(orig_pte));
1775 	__set_pte(ptep, pte_mknoncont(pte));
1776 }
1777 
1778 #define set_ptes set_ptes
1779 static __always_inline void set_ptes(struct mm_struct *mm, unsigned long addr,
1780 				pte_t *ptep, pte_t pte, unsigned int nr)
1781 {
1782 	pte = pte_mknoncont(pte);
1783 
1784 	if (likely(nr == 1)) {
1785 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1786 		__set_ptes(mm, addr, ptep, pte, 1);
1787 		contpte_try_fold(mm, addr, ptep, pte);
1788 	} else {
1789 		contpte_set_ptes(mm, addr, ptep, pte, nr);
1790 	}
1791 }
1792 
1793 static inline void pte_clear(struct mm_struct *mm,
1794 				unsigned long addr, pte_t *ptep)
1795 {
1796 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1797 	__pte_clear(mm, addr, ptep);
1798 }
1799 
1800 #define clear_full_ptes clear_full_ptes
1801 static inline void clear_full_ptes(struct mm_struct *mm, unsigned long addr,
1802 				pte_t *ptep, unsigned int nr, int full)
1803 {
1804 	if (likely(nr == 1)) {
1805 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1806 		__clear_full_ptes(mm, addr, ptep, nr, full);
1807 	} else {
1808 		contpte_clear_full_ptes(mm, addr, ptep, nr, full);
1809 	}
1810 }
1811 
1812 #define get_and_clear_full_ptes get_and_clear_full_ptes
1813 static inline pte_t get_and_clear_full_ptes(struct mm_struct *mm,
1814 				unsigned long addr, pte_t *ptep,
1815 				unsigned int nr, int full)
1816 {
1817 	pte_t pte;
1818 
1819 	if (likely(nr == 1)) {
1820 		contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1821 		pte = __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1822 	} else {
1823 		pte = contpte_get_and_clear_full_ptes(mm, addr, ptep, nr, full);
1824 	}
1825 
1826 	return pte;
1827 }
1828 
1829 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1830 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
1831 				unsigned long addr, pte_t *ptep)
1832 {
1833 	contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
1834 	return __ptep_get_and_clear(mm, addr, ptep);
1835 }
1836 
1837 static inline bool ptep_try_set(pte_t *ptep, pte_t new_pte)
1838 {
1839 	pteval_t old = 0;
1840 
1841 	if (!try_cmpxchg(&pte_val(*ptep), &old, pte_val(new_pte)))
1842 		return false;
1843 
1844 	/*
1845 	 * The store must be complete by the time this returns, but the caller
1846 	 * may be in lazy MMU mode, where __set_pte_complete() would defer the
1847 	 * barriers. Issue them directly.
1848 	 */
1849 	emit_pte_barriers();
1850 	return true;
1851 }
1852 #define ptep_try_set ptep_try_set
1853 
1854 /*
1855  * arm64 mandates break-before-make: a cleared kernel PTE must have its TLB
1856  * invalidated before a different page is installed in its place. The broadcast
1857  * TLBI is an instruction, not an IPI, so this is safe with interrupts disabled.
1858  */
1859 static inline void flush_tlb_before_set(unsigned long addr)
1860 {
1861 	flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
1862 }
1863 #define flush_tlb_before_set flush_tlb_before_set
1864 
1865 #define test_and_clear_young_ptes test_and_clear_young_ptes
1866 static inline bool test_and_clear_young_ptes(struct vm_area_struct *vma,
1867 		unsigned long addr, pte_t *ptep, unsigned int nr)
1868 {
1869 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1870 		return __ptep_test_and_clear_young(vma, addr, ptep);
1871 
1872 	return contpte_test_and_clear_young_ptes(vma, addr, ptep, nr);
1873 }
1874 
1875 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1876 static inline bool ptep_test_and_clear_young(struct vm_area_struct *vma,
1877 		unsigned long addr, pte_t *ptep)
1878 {
1879 	return test_and_clear_young_ptes(vma, addr, ptep, 1);
1880 }
1881 
1882 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1883 static inline bool ptep_clear_flush_young(struct vm_area_struct *vma,
1884 		unsigned long addr, pte_t *ptep)
1885 {
1886 	pte_t orig_pte = __ptep_get(ptep);
1887 
1888 	if (likely(!pte_valid_cont(orig_pte)))
1889 		return __ptep_clear_flush_young(vma, addr, ptep);
1890 
1891 	return contpte_clear_flush_young_ptes(vma, addr, ptep, 1);
1892 }
1893 
1894 #define clear_flush_young_ptes clear_flush_young_ptes
1895 static inline bool clear_flush_young_ptes(struct vm_area_struct *vma,
1896 		unsigned long addr, pte_t *ptep, unsigned int nr)
1897 {
1898 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1899 		return __ptep_clear_flush_young(vma, addr, ptep);
1900 
1901 	return contpte_clear_flush_young_ptes(vma, addr, ptep, nr);
1902 }
1903 
1904 #define wrprotect_ptes wrprotect_ptes
1905 static __always_inline void wrprotect_ptes(struct mm_struct *mm,
1906 				unsigned long addr, pte_t *ptep, unsigned int nr)
1907 {
1908 	if (likely(nr == 1)) {
1909 		/*
1910 		 * Optimization: wrprotect_ptes() can only be called for present
1911 		 * ptes so we only need to check contig bit as condition for
1912 		 * unfold, and we can remove the contig bit from the pte we read
1913 		 * to avoid re-reading. This speeds up fork() which is sensitive
1914 		 * for order-0 folios. Equivalent to contpte_try_unfold().
1915 		 */
1916 		pte_t orig_pte = __ptep_get(ptep);
1917 
1918 		if (unlikely(pte_cont(orig_pte))) {
1919 			__contpte_try_unfold(mm, addr, ptep, orig_pte);
1920 			orig_pte = pte_mknoncont(orig_pte);
1921 		}
1922 		___ptep_set_wrprotect(mm, addr, ptep, orig_pte);
1923 	} else {
1924 		contpte_wrprotect_ptes(mm, addr, ptep, nr);
1925 	}
1926 }
1927 
1928 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1929 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1930 				unsigned long addr, pte_t *ptep)
1931 {
1932 	wrprotect_ptes(mm, addr, ptep, 1);
1933 }
1934 
1935 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1936 static inline int ptep_set_access_flags(struct vm_area_struct *vma,
1937 				unsigned long addr, pte_t *ptep,
1938 				pte_t entry, int dirty)
1939 {
1940 	pte_t orig_pte = __ptep_get(ptep);
1941 
1942 	entry = pte_mknoncont(entry);
1943 
1944 	if (likely(!pte_valid_cont(orig_pte)))
1945 		return __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1946 
1947 	return contpte_ptep_set_access_flags(vma, addr, ptep, entry, dirty);
1948 }
1949 
1950 #define clear_young_dirty_ptes clear_young_dirty_ptes
1951 static inline void clear_young_dirty_ptes(struct vm_area_struct *vma,
1952 					  unsigned long addr, pte_t *ptep,
1953 					  unsigned int nr, cydp_t flags)
1954 {
1955 	if (likely(nr == 1 && !pte_cont(__ptep_get(ptep))))
1956 		__clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1957 	else
1958 		contpte_clear_young_dirty_ptes(vma, addr, ptep, nr, flags);
1959 }
1960 
1961 #else /* CONFIG_ARM64_CONTPTE */
1962 
1963 #define ptep_get				__ptep_get
1964 #define set_pte					__set_pte
1965 #define set_ptes				__set_ptes
1966 #define pte_clear				__pte_clear
1967 #define clear_full_ptes				__clear_full_ptes
1968 #define get_and_clear_full_ptes			__get_and_clear_full_ptes
1969 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1970 #define ptep_get_and_clear			__ptep_get_and_clear
1971 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1972 #define ptep_test_and_clear_young		__ptep_test_and_clear_young
1973 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1974 #define ptep_clear_flush_young			__ptep_clear_flush_young
1975 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1976 #define ptep_set_wrprotect			__ptep_set_wrprotect
1977 #define wrprotect_ptes				__wrprotect_ptes
1978 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1979 #define ptep_set_access_flags			__ptep_set_access_flags
1980 #define clear_young_dirty_ptes			__clear_young_dirty_ptes
1981 
1982 #endif /* CONFIG_ARM64_CONTPTE */
1983 
1984 #endif /* !__ASSEMBLER__ */
1985 
1986 #endif /* __ASM_PGTABLE_H */
1987