xref: /openbmc/linux/arch/x86/include/asm/pgtable.h (revision aeb64ff3)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PGTABLE_H
3 #define _ASM_X86_PGTABLE_H
4 
5 #include <linux/mem_encrypt.h>
6 #include <asm/page.h>
7 #include <asm/pgtable_types.h>
8 
9 /*
10  * Macro to mark a page protection value as UC-
11  */
12 #define pgprot_noncached(prot)						\
13 	((boot_cpu_data.x86 > 3)					\
14 	 ? (__pgprot(pgprot_val(prot) |					\
15 		     cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS)))	\
16 	 : (prot))
17 
18 /*
19  * Macros to add or remove encryption attribute
20  */
21 #define pgprot_encrypted(prot)	__pgprot(__sme_set(pgprot_val(prot)))
22 #define pgprot_decrypted(prot)	__pgprot(__sme_clr(pgprot_val(prot)))
23 
24 #ifndef __ASSEMBLY__
25 #include <asm/x86_init.h>
26 #include <asm/fpu/xstate.h>
27 #include <asm/fpu/api.h>
28 
29 extern pgd_t early_top_pgt[PTRS_PER_PGD];
30 int __init __early_make_pgtable(unsigned long address, pmdval_t pmd);
31 
32 void ptdump_walk_pgd_level(struct seq_file *m, pgd_t *pgd);
33 void ptdump_walk_pgd_level_debugfs(struct seq_file *m, pgd_t *pgd, bool user);
34 void ptdump_walk_pgd_level_checkwx(void);
35 void ptdump_walk_user_pgd_level_checkwx(void);
36 
37 #ifdef CONFIG_DEBUG_WX
38 #define debug_checkwx()		ptdump_walk_pgd_level_checkwx()
39 #define debug_checkwx_user()	ptdump_walk_user_pgd_level_checkwx()
40 #else
41 #define debug_checkwx()		do { } while (0)
42 #define debug_checkwx_user()	do { } while (0)
43 #endif
44 
45 /*
46  * ZERO_PAGE is a global shared page that is always zero: used
47  * for zero-mapped memory areas etc..
48  */
49 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
50 	__visible;
51 #define ZERO_PAGE(vaddr) ((void)(vaddr),virt_to_page(empty_zero_page))
52 
53 extern spinlock_t pgd_lock;
54 extern struct list_head pgd_list;
55 
56 extern struct mm_struct *pgd_page_get_mm(struct page *page);
57 
58 extern pmdval_t early_pmd_flags;
59 
60 #ifdef CONFIG_PARAVIRT_XXL
61 #include <asm/paravirt.h>
62 #else  /* !CONFIG_PARAVIRT_XXL */
63 #define set_pte(ptep, pte)		native_set_pte(ptep, pte)
64 #define set_pte_at(mm, addr, ptep, pte)	native_set_pte_at(mm, addr, ptep, pte)
65 
66 #define set_pte_atomic(ptep, pte)					\
67 	native_set_pte_atomic(ptep, pte)
68 
69 #define set_pmd(pmdp, pmd)		native_set_pmd(pmdp, pmd)
70 
71 #ifndef __PAGETABLE_P4D_FOLDED
72 #define set_pgd(pgdp, pgd)		native_set_pgd(pgdp, pgd)
73 #define pgd_clear(pgd)			(pgtable_l5_enabled() ? native_pgd_clear(pgd) : 0)
74 #endif
75 
76 #ifndef set_p4d
77 # define set_p4d(p4dp, p4d)		native_set_p4d(p4dp, p4d)
78 #endif
79 
80 #ifndef __PAGETABLE_PUD_FOLDED
81 #define p4d_clear(p4d)			native_p4d_clear(p4d)
82 #endif
83 
84 #ifndef set_pud
85 # define set_pud(pudp, pud)		native_set_pud(pudp, pud)
86 #endif
87 
88 #ifndef __PAGETABLE_PUD_FOLDED
89 #define pud_clear(pud)			native_pud_clear(pud)
90 #endif
91 
92 #define pte_clear(mm, addr, ptep)	native_pte_clear(mm, addr, ptep)
93 #define pmd_clear(pmd)			native_pmd_clear(pmd)
94 
95 #define pgd_val(x)	native_pgd_val(x)
96 #define __pgd(x)	native_make_pgd(x)
97 
98 #ifndef __PAGETABLE_P4D_FOLDED
99 #define p4d_val(x)	native_p4d_val(x)
100 #define __p4d(x)	native_make_p4d(x)
101 #endif
102 
103 #ifndef __PAGETABLE_PUD_FOLDED
104 #define pud_val(x)	native_pud_val(x)
105 #define __pud(x)	native_make_pud(x)
106 #endif
107 
108 #ifndef __PAGETABLE_PMD_FOLDED
109 #define pmd_val(x)	native_pmd_val(x)
110 #define __pmd(x)	native_make_pmd(x)
111 #endif
112 
113 #define pte_val(x)	native_pte_val(x)
114 #define __pte(x)	native_make_pte(x)
115 
116 #define arch_end_context_switch(prev)	do {} while(0)
117 #endif	/* CONFIG_PARAVIRT_XXL */
118 
119 /*
120  * The following only work if pte_present() is true.
121  * Undefined behaviour if not..
122  */
123 static inline int pte_dirty(pte_t pte)
124 {
125 	return pte_flags(pte) & _PAGE_DIRTY;
126 }
127 
128 
129 static inline u32 read_pkru(void)
130 {
131 	if (boot_cpu_has(X86_FEATURE_OSPKE))
132 		return rdpkru();
133 	return 0;
134 }
135 
136 static inline void write_pkru(u32 pkru)
137 {
138 	struct pkru_state *pk;
139 
140 	if (!boot_cpu_has(X86_FEATURE_OSPKE))
141 		return;
142 
143 	pk = get_xsave_addr(&current->thread.fpu.state.xsave, XFEATURE_PKRU);
144 
145 	/*
146 	 * The PKRU value in xstate needs to be in sync with the value that is
147 	 * written to the CPU. The FPU restore on return to userland would
148 	 * otherwise load the previous value again.
149 	 */
150 	fpregs_lock();
151 	if (pk)
152 		pk->pkru = pkru;
153 	__write_pkru(pkru);
154 	fpregs_unlock();
155 }
156 
157 static inline int pte_young(pte_t pte)
158 {
159 	return pte_flags(pte) & _PAGE_ACCESSED;
160 }
161 
162 static inline int pmd_dirty(pmd_t pmd)
163 {
164 	return pmd_flags(pmd) & _PAGE_DIRTY;
165 }
166 
167 static inline int pmd_young(pmd_t pmd)
168 {
169 	return pmd_flags(pmd) & _PAGE_ACCESSED;
170 }
171 
172 static inline int pud_dirty(pud_t pud)
173 {
174 	return pud_flags(pud) & _PAGE_DIRTY;
175 }
176 
177 static inline int pud_young(pud_t pud)
178 {
179 	return pud_flags(pud) & _PAGE_ACCESSED;
180 }
181 
182 static inline int pte_write(pte_t pte)
183 {
184 	return pte_flags(pte) & _PAGE_RW;
185 }
186 
187 static inline int pte_huge(pte_t pte)
188 {
189 	return pte_flags(pte) & _PAGE_PSE;
190 }
191 
192 static inline int pte_global(pte_t pte)
193 {
194 	return pte_flags(pte) & _PAGE_GLOBAL;
195 }
196 
197 static inline int pte_exec(pte_t pte)
198 {
199 	return !(pte_flags(pte) & _PAGE_NX);
200 }
201 
202 static inline int pte_special(pte_t pte)
203 {
204 	return pte_flags(pte) & _PAGE_SPECIAL;
205 }
206 
207 /* Entries that were set to PROT_NONE are inverted */
208 
209 static inline u64 protnone_mask(u64 val);
210 
211 static inline unsigned long pte_pfn(pte_t pte)
212 {
213 	phys_addr_t pfn = pte_val(pte);
214 	pfn ^= protnone_mask(pfn);
215 	return (pfn & PTE_PFN_MASK) >> PAGE_SHIFT;
216 }
217 
218 static inline unsigned long pmd_pfn(pmd_t pmd)
219 {
220 	phys_addr_t pfn = pmd_val(pmd);
221 	pfn ^= protnone_mask(pfn);
222 	return (pfn & pmd_pfn_mask(pmd)) >> PAGE_SHIFT;
223 }
224 
225 static inline unsigned long pud_pfn(pud_t pud)
226 {
227 	phys_addr_t pfn = pud_val(pud);
228 	pfn ^= protnone_mask(pfn);
229 	return (pfn & pud_pfn_mask(pud)) >> PAGE_SHIFT;
230 }
231 
232 static inline unsigned long p4d_pfn(p4d_t p4d)
233 {
234 	return (p4d_val(p4d) & p4d_pfn_mask(p4d)) >> PAGE_SHIFT;
235 }
236 
237 static inline unsigned long pgd_pfn(pgd_t pgd)
238 {
239 	return (pgd_val(pgd) & PTE_PFN_MASK) >> PAGE_SHIFT;
240 }
241 
242 static inline int p4d_large(p4d_t p4d)
243 {
244 	/* No 512 GiB pages yet */
245 	return 0;
246 }
247 
248 #define pte_page(pte)	pfn_to_page(pte_pfn(pte))
249 
250 static inline int pmd_large(pmd_t pte)
251 {
252 	return pmd_flags(pte) & _PAGE_PSE;
253 }
254 
255 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
256 static inline int pmd_trans_huge(pmd_t pmd)
257 {
258 	return (pmd_val(pmd) & (_PAGE_PSE|_PAGE_DEVMAP)) == _PAGE_PSE;
259 }
260 
261 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
262 static inline int pud_trans_huge(pud_t pud)
263 {
264 	return (pud_val(pud) & (_PAGE_PSE|_PAGE_DEVMAP)) == _PAGE_PSE;
265 }
266 #endif
267 
268 #define has_transparent_hugepage has_transparent_hugepage
269 static inline int has_transparent_hugepage(void)
270 {
271 	return boot_cpu_has(X86_FEATURE_PSE);
272 }
273 
274 #ifdef CONFIG_ARCH_HAS_PTE_DEVMAP
275 static inline int pmd_devmap(pmd_t pmd)
276 {
277 	return !!(pmd_val(pmd) & _PAGE_DEVMAP);
278 }
279 
280 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
281 static inline int pud_devmap(pud_t pud)
282 {
283 	return !!(pud_val(pud) & _PAGE_DEVMAP);
284 }
285 #else
286 static inline int pud_devmap(pud_t pud)
287 {
288 	return 0;
289 }
290 #endif
291 
292 static inline int pgd_devmap(pgd_t pgd)
293 {
294 	return 0;
295 }
296 #endif
297 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
298 
299 static inline pte_t pte_set_flags(pte_t pte, pteval_t set)
300 {
301 	pteval_t v = native_pte_val(pte);
302 
303 	return native_make_pte(v | set);
304 }
305 
306 static inline pte_t pte_clear_flags(pte_t pte, pteval_t clear)
307 {
308 	pteval_t v = native_pte_val(pte);
309 
310 	return native_make_pte(v & ~clear);
311 }
312 
313 static inline pte_t pte_mkclean(pte_t pte)
314 {
315 	return pte_clear_flags(pte, _PAGE_DIRTY);
316 }
317 
318 static inline pte_t pte_mkold(pte_t pte)
319 {
320 	return pte_clear_flags(pte, _PAGE_ACCESSED);
321 }
322 
323 static inline pte_t pte_wrprotect(pte_t pte)
324 {
325 	return pte_clear_flags(pte, _PAGE_RW);
326 }
327 
328 static inline pte_t pte_mkexec(pte_t pte)
329 {
330 	return pte_clear_flags(pte, _PAGE_NX);
331 }
332 
333 static inline pte_t pte_mkdirty(pte_t pte)
334 {
335 	return pte_set_flags(pte, _PAGE_DIRTY | _PAGE_SOFT_DIRTY);
336 }
337 
338 static inline pte_t pte_mkyoung(pte_t pte)
339 {
340 	return pte_set_flags(pte, _PAGE_ACCESSED);
341 }
342 
343 static inline pte_t pte_mkwrite(pte_t pte)
344 {
345 	return pte_set_flags(pte, _PAGE_RW);
346 }
347 
348 static inline pte_t pte_mkhuge(pte_t pte)
349 {
350 	return pte_set_flags(pte, _PAGE_PSE);
351 }
352 
353 static inline pte_t pte_clrhuge(pte_t pte)
354 {
355 	return pte_clear_flags(pte, _PAGE_PSE);
356 }
357 
358 static inline pte_t pte_mkglobal(pte_t pte)
359 {
360 	return pte_set_flags(pte, _PAGE_GLOBAL);
361 }
362 
363 static inline pte_t pte_clrglobal(pte_t pte)
364 {
365 	return pte_clear_flags(pte, _PAGE_GLOBAL);
366 }
367 
368 static inline pte_t pte_mkspecial(pte_t pte)
369 {
370 	return pte_set_flags(pte, _PAGE_SPECIAL);
371 }
372 
373 static inline pte_t pte_mkdevmap(pte_t pte)
374 {
375 	return pte_set_flags(pte, _PAGE_SPECIAL|_PAGE_DEVMAP);
376 }
377 
378 static inline pmd_t pmd_set_flags(pmd_t pmd, pmdval_t set)
379 {
380 	pmdval_t v = native_pmd_val(pmd);
381 
382 	return native_make_pmd(v | set);
383 }
384 
385 static inline pmd_t pmd_clear_flags(pmd_t pmd, pmdval_t clear)
386 {
387 	pmdval_t v = native_pmd_val(pmd);
388 
389 	return native_make_pmd(v & ~clear);
390 }
391 
392 static inline pmd_t pmd_mkold(pmd_t pmd)
393 {
394 	return pmd_clear_flags(pmd, _PAGE_ACCESSED);
395 }
396 
397 static inline pmd_t pmd_mkclean(pmd_t pmd)
398 {
399 	return pmd_clear_flags(pmd, _PAGE_DIRTY);
400 }
401 
402 static inline pmd_t pmd_wrprotect(pmd_t pmd)
403 {
404 	return pmd_clear_flags(pmd, _PAGE_RW);
405 }
406 
407 static inline pmd_t pmd_mkdirty(pmd_t pmd)
408 {
409 	return pmd_set_flags(pmd, _PAGE_DIRTY | _PAGE_SOFT_DIRTY);
410 }
411 
412 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
413 {
414 	return pmd_set_flags(pmd, _PAGE_DEVMAP);
415 }
416 
417 static inline pmd_t pmd_mkhuge(pmd_t pmd)
418 {
419 	return pmd_set_flags(pmd, _PAGE_PSE);
420 }
421 
422 static inline pmd_t pmd_mkyoung(pmd_t pmd)
423 {
424 	return pmd_set_flags(pmd, _PAGE_ACCESSED);
425 }
426 
427 static inline pmd_t pmd_mkwrite(pmd_t pmd)
428 {
429 	return pmd_set_flags(pmd, _PAGE_RW);
430 }
431 
432 static inline pud_t pud_set_flags(pud_t pud, pudval_t set)
433 {
434 	pudval_t v = native_pud_val(pud);
435 
436 	return native_make_pud(v | set);
437 }
438 
439 static inline pud_t pud_clear_flags(pud_t pud, pudval_t clear)
440 {
441 	pudval_t v = native_pud_val(pud);
442 
443 	return native_make_pud(v & ~clear);
444 }
445 
446 static inline pud_t pud_mkold(pud_t pud)
447 {
448 	return pud_clear_flags(pud, _PAGE_ACCESSED);
449 }
450 
451 static inline pud_t pud_mkclean(pud_t pud)
452 {
453 	return pud_clear_flags(pud, _PAGE_DIRTY);
454 }
455 
456 static inline pud_t pud_wrprotect(pud_t pud)
457 {
458 	return pud_clear_flags(pud, _PAGE_RW);
459 }
460 
461 static inline pud_t pud_mkdirty(pud_t pud)
462 {
463 	return pud_set_flags(pud, _PAGE_DIRTY | _PAGE_SOFT_DIRTY);
464 }
465 
466 static inline pud_t pud_mkdevmap(pud_t pud)
467 {
468 	return pud_set_flags(pud, _PAGE_DEVMAP);
469 }
470 
471 static inline pud_t pud_mkhuge(pud_t pud)
472 {
473 	return pud_set_flags(pud, _PAGE_PSE);
474 }
475 
476 static inline pud_t pud_mkyoung(pud_t pud)
477 {
478 	return pud_set_flags(pud, _PAGE_ACCESSED);
479 }
480 
481 static inline pud_t pud_mkwrite(pud_t pud)
482 {
483 	return pud_set_flags(pud, _PAGE_RW);
484 }
485 
486 #ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
487 static inline int pte_soft_dirty(pte_t pte)
488 {
489 	return pte_flags(pte) & _PAGE_SOFT_DIRTY;
490 }
491 
492 static inline int pmd_soft_dirty(pmd_t pmd)
493 {
494 	return pmd_flags(pmd) & _PAGE_SOFT_DIRTY;
495 }
496 
497 static inline int pud_soft_dirty(pud_t pud)
498 {
499 	return pud_flags(pud) & _PAGE_SOFT_DIRTY;
500 }
501 
502 static inline pte_t pte_mksoft_dirty(pte_t pte)
503 {
504 	return pte_set_flags(pte, _PAGE_SOFT_DIRTY);
505 }
506 
507 static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
508 {
509 	return pmd_set_flags(pmd, _PAGE_SOFT_DIRTY);
510 }
511 
512 static inline pud_t pud_mksoft_dirty(pud_t pud)
513 {
514 	return pud_set_flags(pud, _PAGE_SOFT_DIRTY);
515 }
516 
517 static inline pte_t pte_clear_soft_dirty(pte_t pte)
518 {
519 	return pte_clear_flags(pte, _PAGE_SOFT_DIRTY);
520 }
521 
522 static inline pmd_t pmd_clear_soft_dirty(pmd_t pmd)
523 {
524 	return pmd_clear_flags(pmd, _PAGE_SOFT_DIRTY);
525 }
526 
527 static inline pud_t pud_clear_soft_dirty(pud_t pud)
528 {
529 	return pud_clear_flags(pud, _PAGE_SOFT_DIRTY);
530 }
531 
532 #endif /* CONFIG_HAVE_ARCH_SOFT_DIRTY */
533 
534 /*
535  * Mask out unsupported bits in a present pgprot.  Non-present pgprots
536  * can use those bits for other purposes, so leave them be.
537  */
538 static inline pgprotval_t massage_pgprot(pgprot_t pgprot)
539 {
540 	pgprotval_t protval = pgprot_val(pgprot);
541 
542 	if (protval & _PAGE_PRESENT)
543 		protval &= __supported_pte_mask;
544 
545 	return protval;
546 }
547 
548 static inline pgprotval_t check_pgprot(pgprot_t pgprot)
549 {
550 	pgprotval_t massaged_val = massage_pgprot(pgprot);
551 
552 	/* mmdebug.h can not be included here because of dependencies */
553 #ifdef CONFIG_DEBUG_VM
554 	WARN_ONCE(pgprot_val(pgprot) != massaged_val,
555 		  "attempted to set unsupported pgprot: %016llx "
556 		  "bits: %016llx supported: %016llx\n",
557 		  (u64)pgprot_val(pgprot),
558 		  (u64)pgprot_val(pgprot) ^ massaged_val,
559 		  (u64)__supported_pte_mask);
560 #endif
561 
562 	return massaged_val;
563 }
564 
565 static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot)
566 {
567 	phys_addr_t pfn = (phys_addr_t)page_nr << PAGE_SHIFT;
568 	pfn ^= protnone_mask(pgprot_val(pgprot));
569 	pfn &= PTE_PFN_MASK;
570 	return __pte(pfn | check_pgprot(pgprot));
571 }
572 
573 static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
574 {
575 	phys_addr_t pfn = (phys_addr_t)page_nr << PAGE_SHIFT;
576 	pfn ^= protnone_mask(pgprot_val(pgprot));
577 	pfn &= PHYSICAL_PMD_PAGE_MASK;
578 	return __pmd(pfn | check_pgprot(pgprot));
579 }
580 
581 static inline pud_t pfn_pud(unsigned long page_nr, pgprot_t pgprot)
582 {
583 	phys_addr_t pfn = (phys_addr_t)page_nr << PAGE_SHIFT;
584 	pfn ^= protnone_mask(pgprot_val(pgprot));
585 	pfn &= PHYSICAL_PUD_PAGE_MASK;
586 	return __pud(pfn | check_pgprot(pgprot));
587 }
588 
589 static inline pmd_t pmd_mknotpresent(pmd_t pmd)
590 {
591 	return pfn_pmd(pmd_pfn(pmd),
592 		      __pgprot(pmd_flags(pmd) & ~(_PAGE_PRESENT|_PAGE_PROTNONE)));
593 }
594 
595 static inline pud_t pud_mknotpresent(pud_t pud)
596 {
597 	return pfn_pud(pud_pfn(pud),
598 	      __pgprot(pud_flags(pud) & ~(_PAGE_PRESENT|_PAGE_PROTNONE)));
599 }
600 
601 static inline u64 flip_protnone_guard(u64 oldval, u64 val, u64 mask);
602 
603 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
604 {
605 	pteval_t val = pte_val(pte), oldval = val;
606 
607 	/*
608 	 * Chop off the NX bit (if present), and add the NX portion of
609 	 * the newprot (if present):
610 	 */
611 	val &= _PAGE_CHG_MASK;
612 	val |= check_pgprot(newprot) & ~_PAGE_CHG_MASK;
613 	val = flip_protnone_guard(oldval, val, PTE_PFN_MASK);
614 	return __pte(val);
615 }
616 
617 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
618 {
619 	pmdval_t val = pmd_val(pmd), oldval = val;
620 
621 	val &= _HPAGE_CHG_MASK;
622 	val |= check_pgprot(newprot) & ~_HPAGE_CHG_MASK;
623 	val = flip_protnone_guard(oldval, val, PHYSICAL_PMD_PAGE_MASK);
624 	return __pmd(val);
625 }
626 
627 /* mprotect needs to preserve PAT bits when updating vm_page_prot */
628 #define pgprot_modify pgprot_modify
629 static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
630 {
631 	pgprotval_t preservebits = pgprot_val(oldprot) & _PAGE_CHG_MASK;
632 	pgprotval_t addbits = pgprot_val(newprot);
633 	return __pgprot(preservebits | addbits);
634 }
635 
636 #define pte_pgprot(x) __pgprot(pte_flags(x))
637 #define pmd_pgprot(x) __pgprot(pmd_flags(x))
638 #define pud_pgprot(x) __pgprot(pud_flags(x))
639 #define p4d_pgprot(x) __pgprot(p4d_flags(x))
640 
641 #define canon_pgprot(p) __pgprot(massage_pgprot(p))
642 
643 static inline pgprot_t arch_filter_pgprot(pgprot_t prot)
644 {
645 	return canon_pgprot(prot);
646 }
647 
648 static inline int is_new_memtype_allowed(u64 paddr, unsigned long size,
649 					 enum page_cache_mode pcm,
650 					 enum page_cache_mode new_pcm)
651 {
652 	/*
653 	 * PAT type is always WB for untracked ranges, so no need to check.
654 	 */
655 	if (x86_platform.is_untracked_pat_range(paddr, paddr + size))
656 		return 1;
657 
658 	/*
659 	 * Certain new memtypes are not allowed with certain
660 	 * requested memtype:
661 	 * - request is uncached, return cannot be write-back
662 	 * - request is write-combine, return cannot be write-back
663 	 * - request is write-through, return cannot be write-back
664 	 * - request is write-through, return cannot be write-combine
665 	 */
666 	if ((pcm == _PAGE_CACHE_MODE_UC_MINUS &&
667 	     new_pcm == _PAGE_CACHE_MODE_WB) ||
668 	    (pcm == _PAGE_CACHE_MODE_WC &&
669 	     new_pcm == _PAGE_CACHE_MODE_WB) ||
670 	    (pcm == _PAGE_CACHE_MODE_WT &&
671 	     new_pcm == _PAGE_CACHE_MODE_WB) ||
672 	    (pcm == _PAGE_CACHE_MODE_WT &&
673 	     new_pcm == _PAGE_CACHE_MODE_WC)) {
674 		return 0;
675 	}
676 
677 	return 1;
678 }
679 
680 pmd_t *populate_extra_pmd(unsigned long vaddr);
681 pte_t *populate_extra_pte(unsigned long vaddr);
682 
683 #ifdef CONFIG_PAGE_TABLE_ISOLATION
684 pgd_t __pti_set_user_pgtbl(pgd_t *pgdp, pgd_t pgd);
685 
686 /*
687  * Take a PGD location (pgdp) and a pgd value that needs to be set there.
688  * Populates the user and returns the resulting PGD that must be set in
689  * the kernel copy of the page tables.
690  */
691 static inline pgd_t pti_set_user_pgtbl(pgd_t *pgdp, pgd_t pgd)
692 {
693 	if (!static_cpu_has(X86_FEATURE_PTI))
694 		return pgd;
695 	return __pti_set_user_pgtbl(pgdp, pgd);
696 }
697 #else   /* CONFIG_PAGE_TABLE_ISOLATION */
698 static inline pgd_t pti_set_user_pgtbl(pgd_t *pgdp, pgd_t pgd)
699 {
700 	return pgd;
701 }
702 #endif  /* CONFIG_PAGE_TABLE_ISOLATION */
703 
704 #endif	/* __ASSEMBLY__ */
705 
706 
707 #ifdef CONFIG_X86_32
708 # include <asm/pgtable_32.h>
709 #else
710 # include <asm/pgtable_64.h>
711 #endif
712 
713 #ifndef __ASSEMBLY__
714 #include <linux/mm_types.h>
715 #include <linux/mmdebug.h>
716 #include <linux/log2.h>
717 #include <asm/fixmap.h>
718 
719 static inline int pte_none(pte_t pte)
720 {
721 	return !(pte.pte & ~(_PAGE_KNL_ERRATUM_MASK));
722 }
723 
724 #define __HAVE_ARCH_PTE_SAME
725 static inline int pte_same(pte_t a, pte_t b)
726 {
727 	return a.pte == b.pte;
728 }
729 
730 static inline int pte_present(pte_t a)
731 {
732 	return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE);
733 }
734 
735 #ifdef CONFIG_ARCH_HAS_PTE_DEVMAP
736 static inline int pte_devmap(pte_t a)
737 {
738 	return (pte_flags(a) & _PAGE_DEVMAP) == _PAGE_DEVMAP;
739 }
740 #endif
741 
742 #define pte_accessible pte_accessible
743 static inline bool pte_accessible(struct mm_struct *mm, pte_t a)
744 {
745 	if (pte_flags(a) & _PAGE_PRESENT)
746 		return true;
747 
748 	if ((pte_flags(a) & _PAGE_PROTNONE) &&
749 			mm_tlb_flush_pending(mm))
750 		return true;
751 
752 	return false;
753 }
754 
755 static inline int pmd_present(pmd_t pmd)
756 {
757 	/*
758 	 * Checking for _PAGE_PSE is needed too because
759 	 * split_huge_page will temporarily clear the present bit (but
760 	 * the _PAGE_PSE flag will remain set at all times while the
761 	 * _PAGE_PRESENT bit is clear).
762 	 */
763 	return pmd_flags(pmd) & (_PAGE_PRESENT | _PAGE_PROTNONE | _PAGE_PSE);
764 }
765 
766 #ifdef CONFIG_NUMA_BALANCING
767 /*
768  * These work without NUMA balancing but the kernel does not care. See the
769  * comment in include/asm-generic/pgtable.h
770  */
771 static inline int pte_protnone(pte_t pte)
772 {
773 	return (pte_flags(pte) & (_PAGE_PROTNONE | _PAGE_PRESENT))
774 		== _PAGE_PROTNONE;
775 }
776 
777 static inline int pmd_protnone(pmd_t pmd)
778 {
779 	return (pmd_flags(pmd) & (_PAGE_PROTNONE | _PAGE_PRESENT))
780 		== _PAGE_PROTNONE;
781 }
782 #endif /* CONFIG_NUMA_BALANCING */
783 
784 static inline int pmd_none(pmd_t pmd)
785 {
786 	/* Only check low word on 32-bit platforms, since it might be
787 	   out of sync with upper half. */
788 	unsigned long val = native_pmd_val(pmd);
789 	return (val & ~_PAGE_KNL_ERRATUM_MASK) == 0;
790 }
791 
792 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
793 {
794 	return (unsigned long)__va(pmd_val(pmd) & pmd_pfn_mask(pmd));
795 }
796 
797 /*
798  * Currently stuck as a macro due to indirect forward reference to
799  * linux/mmzone.h's __section_mem_map_addr() definition:
800  */
801 #define pmd_page(pmd)	pfn_to_page(pmd_pfn(pmd))
802 
803 /*
804  * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
805  *
806  * this macro returns the index of the entry in the pmd page which would
807  * control the given virtual address
808  */
809 static inline unsigned long pmd_index(unsigned long address)
810 {
811 	return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
812 }
813 
814 /*
815  * Conversion functions: convert a page and protection to a page entry,
816  * and a page entry and page directory to the page they refer to.
817  *
818  * (Currently stuck as a macro because of indirect forward reference
819  * to linux/mm.h:page_to_nid())
820  */
821 #define mk_pte(page, pgprot)   pfn_pte(page_to_pfn(page), (pgprot))
822 
823 /*
824  * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
825  *
826  * this function returns the index of the entry in the pte page which would
827  * control the given virtual address
828  */
829 static inline unsigned long pte_index(unsigned long address)
830 {
831 	return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
832 }
833 
834 static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address)
835 {
836 	return (pte_t *)pmd_page_vaddr(*pmd) + pte_index(address);
837 }
838 
839 static inline int pmd_bad(pmd_t pmd)
840 {
841 	return (pmd_flags(pmd) & ~_PAGE_USER) != _KERNPG_TABLE;
842 }
843 
844 static inline unsigned long pages_to_mb(unsigned long npg)
845 {
846 	return npg >> (20 - PAGE_SHIFT);
847 }
848 
849 #if CONFIG_PGTABLE_LEVELS > 2
850 static inline int pud_none(pud_t pud)
851 {
852 	return (native_pud_val(pud) & ~(_PAGE_KNL_ERRATUM_MASK)) == 0;
853 }
854 
855 static inline int pud_present(pud_t pud)
856 {
857 	return pud_flags(pud) & _PAGE_PRESENT;
858 }
859 
860 static inline unsigned long pud_page_vaddr(pud_t pud)
861 {
862 	return (unsigned long)__va(pud_val(pud) & pud_pfn_mask(pud));
863 }
864 
865 /*
866  * Currently stuck as a macro due to indirect forward reference to
867  * linux/mmzone.h's __section_mem_map_addr() definition:
868  */
869 #define pud_page(pud)	pfn_to_page(pud_pfn(pud))
870 
871 /* Find an entry in the second-level page table.. */
872 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
873 {
874 	return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
875 }
876 
877 static inline int pud_large(pud_t pud)
878 {
879 	return (pud_val(pud) & (_PAGE_PSE | _PAGE_PRESENT)) ==
880 		(_PAGE_PSE | _PAGE_PRESENT);
881 }
882 
883 static inline int pud_bad(pud_t pud)
884 {
885 	return (pud_flags(pud) & ~(_KERNPG_TABLE | _PAGE_USER)) != 0;
886 }
887 #else
888 static inline int pud_large(pud_t pud)
889 {
890 	return 0;
891 }
892 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
893 
894 static inline unsigned long pud_index(unsigned long address)
895 {
896 	return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1);
897 }
898 
899 #if CONFIG_PGTABLE_LEVELS > 3
900 static inline int p4d_none(p4d_t p4d)
901 {
902 	return (native_p4d_val(p4d) & ~(_PAGE_KNL_ERRATUM_MASK)) == 0;
903 }
904 
905 static inline int p4d_present(p4d_t p4d)
906 {
907 	return p4d_flags(p4d) & _PAGE_PRESENT;
908 }
909 
910 static inline unsigned long p4d_page_vaddr(p4d_t p4d)
911 {
912 	return (unsigned long)__va(p4d_val(p4d) & p4d_pfn_mask(p4d));
913 }
914 
915 /*
916  * Currently stuck as a macro due to indirect forward reference to
917  * linux/mmzone.h's __section_mem_map_addr() definition:
918  */
919 #define p4d_page(p4d)	pfn_to_page(p4d_pfn(p4d))
920 
921 /* Find an entry in the third-level page table.. */
922 static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
923 {
924 	return (pud_t *)p4d_page_vaddr(*p4d) + pud_index(address);
925 }
926 
927 static inline int p4d_bad(p4d_t p4d)
928 {
929 	unsigned long ignore_flags = _KERNPG_TABLE | _PAGE_USER;
930 
931 	if (IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION))
932 		ignore_flags |= _PAGE_NX;
933 
934 	return (p4d_flags(p4d) & ~ignore_flags) != 0;
935 }
936 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
937 
938 static inline unsigned long p4d_index(unsigned long address)
939 {
940 	return (address >> P4D_SHIFT) & (PTRS_PER_P4D - 1);
941 }
942 
943 #if CONFIG_PGTABLE_LEVELS > 4
944 static inline int pgd_present(pgd_t pgd)
945 {
946 	if (!pgtable_l5_enabled())
947 		return 1;
948 	return pgd_flags(pgd) & _PAGE_PRESENT;
949 }
950 
951 static inline unsigned long pgd_page_vaddr(pgd_t pgd)
952 {
953 	return (unsigned long)__va((unsigned long)pgd_val(pgd) & PTE_PFN_MASK);
954 }
955 
956 /*
957  * Currently stuck as a macro due to indirect forward reference to
958  * linux/mmzone.h's __section_mem_map_addr() definition:
959  */
960 #define pgd_page(pgd)	pfn_to_page(pgd_pfn(pgd))
961 
962 /* to find an entry in a page-table-directory. */
963 static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
964 {
965 	if (!pgtable_l5_enabled())
966 		return (p4d_t *)pgd;
967 	return (p4d_t *)pgd_page_vaddr(*pgd) + p4d_index(address);
968 }
969 
970 static inline int pgd_bad(pgd_t pgd)
971 {
972 	unsigned long ignore_flags = _PAGE_USER;
973 
974 	if (!pgtable_l5_enabled())
975 		return 0;
976 
977 	if (IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION))
978 		ignore_flags |= _PAGE_NX;
979 
980 	return (pgd_flags(pgd) & ~ignore_flags) != _KERNPG_TABLE;
981 }
982 
983 static inline int pgd_none(pgd_t pgd)
984 {
985 	if (!pgtable_l5_enabled())
986 		return 0;
987 	/*
988 	 * There is no need to do a workaround for the KNL stray
989 	 * A/D bit erratum here.  PGDs only point to page tables
990 	 * except on 32-bit non-PAE which is not supported on
991 	 * KNL.
992 	 */
993 	return !native_pgd_val(pgd);
994 }
995 #endif	/* CONFIG_PGTABLE_LEVELS > 4 */
996 
997 #endif	/* __ASSEMBLY__ */
998 
999 /*
1000  * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
1001  *
1002  * this macro returns the index of the entry in the pgd page which would
1003  * control the given virtual address
1004  */
1005 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
1006 
1007 /*
1008  * pgd_offset() returns a (pgd_t *)
1009  * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
1010  */
1011 #define pgd_offset_pgd(pgd, address) (pgd + pgd_index((address)))
1012 /*
1013  * a shortcut to get a pgd_t in a given mm
1014  */
1015 #define pgd_offset(mm, address) pgd_offset_pgd((mm)->pgd, (address))
1016 /*
1017  * a shortcut which implies the use of the kernel's pgd, instead
1018  * of a process's
1019  */
1020 #define pgd_offset_k(address) pgd_offset(&init_mm, (address))
1021 
1022 
1023 #define KERNEL_PGD_BOUNDARY	pgd_index(PAGE_OFFSET)
1024 #define KERNEL_PGD_PTRS		(PTRS_PER_PGD - KERNEL_PGD_BOUNDARY)
1025 
1026 #ifndef __ASSEMBLY__
1027 
1028 extern int direct_gbpages;
1029 void init_mem_mapping(void);
1030 void early_alloc_pgt_buf(void);
1031 extern void memblock_find_dma_reserve(void);
1032 
1033 #ifdef CONFIG_X86_64
1034 /* Realmode trampoline initialization. */
1035 extern pgd_t trampoline_pgd_entry;
1036 static inline void __meminit init_trampoline_default(void)
1037 {
1038 	/* Default trampoline pgd value */
1039 	trampoline_pgd_entry = init_top_pgt[pgd_index(__PAGE_OFFSET)];
1040 }
1041 
1042 void __init poking_init(void);
1043 
1044 # ifdef CONFIG_RANDOMIZE_MEMORY
1045 void __meminit init_trampoline(void);
1046 # else
1047 #  define init_trampoline init_trampoline_default
1048 # endif
1049 #else
1050 static inline void init_trampoline(void) { }
1051 #endif
1052 
1053 /* local pte updates need not use xchg for locking */
1054 static inline pte_t native_local_ptep_get_and_clear(pte_t *ptep)
1055 {
1056 	pte_t res = *ptep;
1057 
1058 	/* Pure native function needs no input for mm, addr */
1059 	native_pte_clear(NULL, 0, ptep);
1060 	return res;
1061 }
1062 
1063 static inline pmd_t native_local_pmdp_get_and_clear(pmd_t *pmdp)
1064 {
1065 	pmd_t res = *pmdp;
1066 
1067 	native_pmd_clear(pmdp);
1068 	return res;
1069 }
1070 
1071 static inline pud_t native_local_pudp_get_and_clear(pud_t *pudp)
1072 {
1073 	pud_t res = *pudp;
1074 
1075 	native_pud_clear(pudp);
1076 	return res;
1077 }
1078 
1079 static inline void native_set_pte_at(struct mm_struct *mm, unsigned long addr,
1080 				     pte_t *ptep , pte_t pte)
1081 {
1082 	native_set_pte(ptep, pte);
1083 }
1084 
1085 static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
1086 			      pmd_t *pmdp, pmd_t pmd)
1087 {
1088 	set_pmd(pmdp, pmd);
1089 }
1090 
1091 static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
1092 			      pud_t *pudp, pud_t pud)
1093 {
1094 	native_set_pud(pudp, pud);
1095 }
1096 
1097 /*
1098  * We only update the dirty/accessed state if we set
1099  * the dirty bit by hand in the kernel, since the hardware
1100  * will do the accessed bit for us, and we don't want to
1101  * race with other CPU's that might be updating the dirty
1102  * bit at the same time.
1103  */
1104 struct vm_area_struct;
1105 
1106 #define  __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
1107 extern int ptep_set_access_flags(struct vm_area_struct *vma,
1108 				 unsigned long address, pte_t *ptep,
1109 				 pte_t entry, int dirty);
1110 
1111 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
1112 extern int ptep_test_and_clear_young(struct vm_area_struct *vma,
1113 				     unsigned long addr, pte_t *ptep);
1114 
1115 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
1116 extern int ptep_clear_flush_young(struct vm_area_struct *vma,
1117 				  unsigned long address, pte_t *ptep);
1118 
1119 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
1120 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
1121 				       pte_t *ptep)
1122 {
1123 	pte_t pte = native_ptep_get_and_clear(ptep);
1124 	return pte;
1125 }
1126 
1127 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
1128 static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
1129 					    unsigned long addr, pte_t *ptep,
1130 					    int full)
1131 {
1132 	pte_t pte;
1133 	if (full) {
1134 		/*
1135 		 * Full address destruction in progress; paravirt does not
1136 		 * care about updates and native needs no locking
1137 		 */
1138 		pte = native_local_ptep_get_and_clear(ptep);
1139 	} else {
1140 		pte = ptep_get_and_clear(mm, addr, ptep);
1141 	}
1142 	return pte;
1143 }
1144 
1145 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
1146 static inline void ptep_set_wrprotect(struct mm_struct *mm,
1147 				      unsigned long addr, pte_t *ptep)
1148 {
1149 	clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte);
1150 }
1151 
1152 #define flush_tlb_fix_spurious_fault(vma, address) do { } while (0)
1153 
1154 #define mk_pmd(page, pgprot)   pfn_pmd(page_to_pfn(page), (pgprot))
1155 
1156 #define  __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
1157 extern int pmdp_set_access_flags(struct vm_area_struct *vma,
1158 				 unsigned long address, pmd_t *pmdp,
1159 				 pmd_t entry, int dirty);
1160 extern int pudp_set_access_flags(struct vm_area_struct *vma,
1161 				 unsigned long address, pud_t *pudp,
1162 				 pud_t entry, int dirty);
1163 
1164 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
1165 extern int pmdp_test_and_clear_young(struct vm_area_struct *vma,
1166 				     unsigned long addr, pmd_t *pmdp);
1167 extern int pudp_test_and_clear_young(struct vm_area_struct *vma,
1168 				     unsigned long addr, pud_t *pudp);
1169 
1170 #define __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
1171 extern int pmdp_clear_flush_young(struct vm_area_struct *vma,
1172 				  unsigned long address, pmd_t *pmdp);
1173 
1174 
1175 #define pmd_write pmd_write
1176 static inline int pmd_write(pmd_t pmd)
1177 {
1178 	return pmd_flags(pmd) & _PAGE_RW;
1179 }
1180 
1181 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
1182 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr,
1183 				       pmd_t *pmdp)
1184 {
1185 	return native_pmdp_get_and_clear(pmdp);
1186 }
1187 
1188 #define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR
1189 static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm,
1190 					unsigned long addr, pud_t *pudp)
1191 {
1192 	return native_pudp_get_and_clear(pudp);
1193 }
1194 
1195 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
1196 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
1197 				      unsigned long addr, pmd_t *pmdp)
1198 {
1199 	clear_bit(_PAGE_BIT_RW, (unsigned long *)pmdp);
1200 }
1201 
1202 #define pud_write pud_write
1203 static inline int pud_write(pud_t pud)
1204 {
1205 	return pud_flags(pud) & _PAGE_RW;
1206 }
1207 
1208 #ifndef pmdp_establish
1209 #define pmdp_establish pmdp_establish
1210 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
1211 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
1212 {
1213 	if (IS_ENABLED(CONFIG_SMP)) {
1214 		return xchg(pmdp, pmd);
1215 	} else {
1216 		pmd_t old = *pmdp;
1217 		WRITE_ONCE(*pmdp, pmd);
1218 		return old;
1219 	}
1220 }
1221 #endif
1222 /*
1223  * Page table pages are page-aligned.  The lower half of the top
1224  * level is used for userspace and the top half for the kernel.
1225  *
1226  * Returns true for parts of the PGD that map userspace and
1227  * false for the parts that map the kernel.
1228  */
1229 static inline bool pgdp_maps_userspace(void *__ptr)
1230 {
1231 	unsigned long ptr = (unsigned long)__ptr;
1232 
1233 	return (((ptr & ~PAGE_MASK) / sizeof(pgd_t)) < PGD_KERNEL_START);
1234 }
1235 
1236 static inline int pgd_large(pgd_t pgd) { return 0; }
1237 
1238 #ifdef CONFIG_PAGE_TABLE_ISOLATION
1239 /*
1240  * All top-level PAGE_TABLE_ISOLATION page tables are order-1 pages
1241  * (8k-aligned and 8k in size).  The kernel one is at the beginning 4k and
1242  * the user one is in the last 4k.  To switch between them, you
1243  * just need to flip the 12th bit in their addresses.
1244  */
1245 #define PTI_PGTABLE_SWITCH_BIT	PAGE_SHIFT
1246 
1247 /*
1248  * This generates better code than the inline assembly in
1249  * __set_bit().
1250  */
1251 static inline void *ptr_set_bit(void *ptr, int bit)
1252 {
1253 	unsigned long __ptr = (unsigned long)ptr;
1254 
1255 	__ptr |= BIT(bit);
1256 	return (void *)__ptr;
1257 }
1258 static inline void *ptr_clear_bit(void *ptr, int bit)
1259 {
1260 	unsigned long __ptr = (unsigned long)ptr;
1261 
1262 	__ptr &= ~BIT(bit);
1263 	return (void *)__ptr;
1264 }
1265 
1266 static inline pgd_t *kernel_to_user_pgdp(pgd_t *pgdp)
1267 {
1268 	return ptr_set_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
1269 }
1270 
1271 static inline pgd_t *user_to_kernel_pgdp(pgd_t *pgdp)
1272 {
1273 	return ptr_clear_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
1274 }
1275 
1276 static inline p4d_t *kernel_to_user_p4dp(p4d_t *p4dp)
1277 {
1278 	return ptr_set_bit(p4dp, PTI_PGTABLE_SWITCH_BIT);
1279 }
1280 
1281 static inline p4d_t *user_to_kernel_p4dp(p4d_t *p4dp)
1282 {
1283 	return ptr_clear_bit(p4dp, PTI_PGTABLE_SWITCH_BIT);
1284 }
1285 #endif /* CONFIG_PAGE_TABLE_ISOLATION */
1286 
1287 /*
1288  * clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
1289  *
1290  *  dst - pointer to pgd range anwhere on a pgd page
1291  *  src - ""
1292  *  count - the number of pgds to copy.
1293  *
1294  * dst and src can be on the same page, but the range must not overlap,
1295  * and must not cross a page boundary.
1296  */
1297 static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
1298 {
1299 	memcpy(dst, src, count * sizeof(pgd_t));
1300 #ifdef CONFIG_PAGE_TABLE_ISOLATION
1301 	if (!static_cpu_has(X86_FEATURE_PTI))
1302 		return;
1303 	/* Clone the user space pgd as well */
1304 	memcpy(kernel_to_user_pgdp(dst), kernel_to_user_pgdp(src),
1305 	       count * sizeof(pgd_t));
1306 #endif
1307 }
1308 
1309 #define PTE_SHIFT ilog2(PTRS_PER_PTE)
1310 static inline int page_level_shift(enum pg_level level)
1311 {
1312 	return (PAGE_SHIFT - PTE_SHIFT) + level * PTE_SHIFT;
1313 }
1314 static inline unsigned long page_level_size(enum pg_level level)
1315 {
1316 	return 1UL << page_level_shift(level);
1317 }
1318 static inline unsigned long page_level_mask(enum pg_level level)
1319 {
1320 	return ~(page_level_size(level) - 1);
1321 }
1322 
1323 /*
1324  * The x86 doesn't have any external MMU info: the kernel page
1325  * tables contain all the necessary information.
1326  */
1327 static inline void update_mmu_cache(struct vm_area_struct *vma,
1328 		unsigned long addr, pte_t *ptep)
1329 {
1330 }
1331 static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
1332 		unsigned long addr, pmd_t *pmd)
1333 {
1334 }
1335 static inline void update_mmu_cache_pud(struct vm_area_struct *vma,
1336 		unsigned long addr, pud_t *pud)
1337 {
1338 }
1339 
1340 #ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY
1341 static inline pte_t pte_swp_mksoft_dirty(pte_t pte)
1342 {
1343 	return pte_set_flags(pte, _PAGE_SWP_SOFT_DIRTY);
1344 }
1345 
1346 static inline int pte_swp_soft_dirty(pte_t pte)
1347 {
1348 	return pte_flags(pte) & _PAGE_SWP_SOFT_DIRTY;
1349 }
1350 
1351 static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
1352 {
1353 	return pte_clear_flags(pte, _PAGE_SWP_SOFT_DIRTY);
1354 }
1355 
1356 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1357 static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd)
1358 {
1359 	return pmd_set_flags(pmd, _PAGE_SWP_SOFT_DIRTY);
1360 }
1361 
1362 static inline int pmd_swp_soft_dirty(pmd_t pmd)
1363 {
1364 	return pmd_flags(pmd) & _PAGE_SWP_SOFT_DIRTY;
1365 }
1366 
1367 static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd)
1368 {
1369 	return pmd_clear_flags(pmd, _PAGE_SWP_SOFT_DIRTY);
1370 }
1371 #endif
1372 #endif
1373 
1374 #define PKRU_AD_BIT 0x1
1375 #define PKRU_WD_BIT 0x2
1376 #define PKRU_BITS_PER_PKEY 2
1377 
1378 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
1379 extern u32 init_pkru_value;
1380 #else
1381 #define init_pkru_value	0
1382 #endif
1383 
1384 static inline bool __pkru_allows_read(u32 pkru, u16 pkey)
1385 {
1386 	int pkru_pkey_bits = pkey * PKRU_BITS_PER_PKEY;
1387 	return !(pkru & (PKRU_AD_BIT << pkru_pkey_bits));
1388 }
1389 
1390 static inline bool __pkru_allows_write(u32 pkru, u16 pkey)
1391 {
1392 	int pkru_pkey_bits = pkey * PKRU_BITS_PER_PKEY;
1393 	/*
1394 	 * Access-disable disables writes too so we need to check
1395 	 * both bits here.
1396 	 */
1397 	return !(pkru & ((PKRU_AD_BIT|PKRU_WD_BIT) << pkru_pkey_bits));
1398 }
1399 
1400 static inline u16 pte_flags_pkey(unsigned long pte_flags)
1401 {
1402 #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
1403 	/* ifdef to avoid doing 59-bit shift on 32-bit values */
1404 	return (pte_flags & _PAGE_PKEY_MASK) >> _PAGE_BIT_PKEY_BIT0;
1405 #else
1406 	return 0;
1407 #endif
1408 }
1409 
1410 static inline bool __pkru_allows_pkey(u16 pkey, bool write)
1411 {
1412 	u32 pkru = read_pkru();
1413 
1414 	if (!__pkru_allows_read(pkru, pkey))
1415 		return false;
1416 	if (write && !__pkru_allows_write(pkru, pkey))
1417 		return false;
1418 
1419 	return true;
1420 }
1421 
1422 /*
1423  * 'pteval' can come from a PTE, PMD or PUD.  We only check
1424  * _PAGE_PRESENT, _PAGE_USER, and _PAGE_RW in here which are the
1425  * same value on all 3 types.
1426  */
1427 static inline bool __pte_access_permitted(unsigned long pteval, bool write)
1428 {
1429 	unsigned long need_pte_bits = _PAGE_PRESENT|_PAGE_USER;
1430 
1431 	if (write)
1432 		need_pte_bits |= _PAGE_RW;
1433 
1434 	if ((pteval & need_pte_bits) != need_pte_bits)
1435 		return 0;
1436 
1437 	return __pkru_allows_pkey(pte_flags_pkey(pteval), write);
1438 }
1439 
1440 #define pte_access_permitted pte_access_permitted
1441 static inline bool pte_access_permitted(pte_t pte, bool write)
1442 {
1443 	return __pte_access_permitted(pte_val(pte), write);
1444 }
1445 
1446 #define pmd_access_permitted pmd_access_permitted
1447 static inline bool pmd_access_permitted(pmd_t pmd, bool write)
1448 {
1449 	return __pte_access_permitted(pmd_val(pmd), write);
1450 }
1451 
1452 #define pud_access_permitted pud_access_permitted
1453 static inline bool pud_access_permitted(pud_t pud, bool write)
1454 {
1455 	return __pte_access_permitted(pud_val(pud), write);
1456 }
1457 
1458 #define __HAVE_ARCH_PFN_MODIFY_ALLOWED 1
1459 extern bool pfn_modify_allowed(unsigned long pfn, pgprot_t prot);
1460 
1461 static inline bool arch_has_pfn_modify_check(void)
1462 {
1463 	return boot_cpu_has_bug(X86_BUG_L1TF);
1464 }
1465 
1466 #define arch_faults_on_old_pte arch_faults_on_old_pte
1467 static inline bool arch_faults_on_old_pte(void)
1468 {
1469 	return false;
1470 }
1471 
1472 #include <asm-generic/pgtable.h>
1473 #endif	/* __ASSEMBLY__ */
1474 
1475 #endif /* _ASM_X86_PGTABLE_H */
1476