xref: /openbmc/linux/arch/arm64/include/asm/pgtable.h (revision be58f710)
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, PCI I/O space
22  *	and fixed mappings
23  */
24 #define VMALLOC_START		(MODULES_END)
25 #define VMALLOC_END		(VMEMMAP_START - SZ_256M)
26 
27 #define vmemmap			((struct page *)VMEMMAP_START - (memstart_addr >> PAGE_SHIFT))
28 
29 #ifndef __ASSEMBLY__
30 
31 #include <asm/cmpxchg.h>
32 #include <asm/fixmap.h>
33 #include <linux/mmdebug.h>
34 #include <linux/mm_types.h>
35 #include <linux/sched.h>
36 
37 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
38 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
39 
40 /* Set stride and tlb_level in flush_*_tlb_range */
41 #define flush_pmd_tlb_range(vma, addr, end)	\
42 	__flush_tlb_range(vma, addr, end, PMD_SIZE, false, 2)
43 #define flush_pud_tlb_range(vma, addr, end)	\
44 	__flush_tlb_range(vma, addr, end, PUD_SIZE, false, 1)
45 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
46 
47 /*
48  * Outside of a few very special situations (e.g. hibernation), we always
49  * use broadcast TLB invalidation instructions, therefore a spurious page
50  * fault on one CPU which has been handled concurrently by another CPU
51  * does not need to perform additional invalidation.
52  */
53 #define flush_tlb_fix_spurious_fault(vma, address) do { } while (0)
54 
55 /*
56  * ZERO_PAGE is a global shared page that is always zero: used
57  * for zero-mapped memory areas etc..
58  */
59 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
60 #define ZERO_PAGE(vaddr)	phys_to_page(__pa_symbol(empty_zero_page))
61 
62 #define pte_ERROR(e)	\
63 	pr_err("%s:%d: bad pte %016llx.\n", __FILE__, __LINE__, pte_val(e))
64 
65 /*
66  * Macros to convert between a physical address and its placement in a
67  * page table entry, taking care of 52-bit addresses.
68  */
69 #ifdef CONFIG_ARM64_PA_BITS_52
70 #define __pte_to_phys(pte)	\
71 	((pte_val(pte) & PTE_ADDR_LOW) | ((pte_val(pte) & PTE_ADDR_HIGH) << 36))
72 #define __phys_to_pte_val(phys)	(((phys) | ((phys) >> 36)) & PTE_ADDR_MASK)
73 #else
74 #define __pte_to_phys(pte)	(pte_val(pte) & PTE_ADDR_MASK)
75 #define __phys_to_pte_val(phys)	(phys)
76 #endif
77 
78 #define pte_pfn(pte)		(__pte_to_phys(pte) >> PAGE_SHIFT)
79 #define pfn_pte(pfn,prot)	\
80 	__pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
81 
82 #define pte_none(pte)		(!pte_val(pte))
83 #define pte_clear(mm,addr,ptep)	set_pte(ptep, __pte(0))
84 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
85 
86 /*
87  * The following only work if pte_present(). Undefined behaviour otherwise.
88  */
89 #define pte_present(pte)	(!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
90 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
91 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
92 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
93 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
94 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
95 #define pte_devmap(pte)		(!!(pte_val(pte) & PTE_DEVMAP))
96 #define pte_tagged(pte)		((pte_val(pte) & PTE_ATTRINDX_MASK) == \
97 				 PTE_ATTRINDX(MT_NORMAL_TAGGED))
98 
99 #define pte_cont_addr_end(addr, end)						\
100 ({	unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK;	\
101 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
102 })
103 
104 #define pmd_cont_addr_end(addr, end)						\
105 ({	unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK;	\
106 	(__boundary - 1 < (end) - 1) ? __boundary : (end);			\
107 })
108 
109 #define pte_hw_dirty(pte)	(pte_write(pte) && !(pte_val(pte) & PTE_RDONLY))
110 #define pte_sw_dirty(pte)	(!!(pte_val(pte) & PTE_DIRTY))
111 #define pte_dirty(pte)		(pte_sw_dirty(pte) || pte_hw_dirty(pte))
112 
113 #define pte_valid(pte)		(!!(pte_val(pte) & PTE_VALID))
114 /*
115  * Execute-only user mappings do not have the PTE_USER bit set. All valid
116  * kernel mappings have the PTE_UXN bit set.
117  */
118 #define pte_valid_not_user(pte) \
119 	((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
120 /*
121  * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
122  * so that we don't erroneously return false for pages that have been
123  * remapped as PROT_NONE but are yet to be flushed from the TLB.
124  * Note that we can't make any assumptions based on the state of the access
125  * flag, since ptep_clear_flush_young() elides a DSB when invalidating the
126  * TLB.
127  */
128 #define pte_accessible(mm, pte)	\
129 	(mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
130 
131 /*
132  * p??_access_permitted() is true for valid user mappings (PTE_USER
133  * bit set, subject to the write permission check). For execute-only
134  * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
135  * not set) must return false. PROT_NONE mappings do not have the
136  * PTE_VALID bit set.
137  */
138 #define pte_access_permitted(pte, write) \
139 	(((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
140 #define pmd_access_permitted(pmd, write) \
141 	(pte_access_permitted(pmd_pte(pmd), (write)))
142 #define pud_access_permitted(pud, write) \
143 	(pte_access_permitted(pud_pte(pud), (write)))
144 
145 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
146 {
147 	pte_val(pte) &= ~pgprot_val(prot);
148 	return pte;
149 }
150 
151 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
152 {
153 	pte_val(pte) |= pgprot_val(prot);
154 	return pte;
155 }
156 
157 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
158 {
159 	pmd_val(pmd) &= ~pgprot_val(prot);
160 	return pmd;
161 }
162 
163 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
164 {
165 	pmd_val(pmd) |= pgprot_val(prot);
166 	return pmd;
167 }
168 
169 static inline pte_t pte_mkwrite(pte_t pte)
170 {
171 	pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
172 	pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
173 	return pte;
174 }
175 
176 static inline pte_t pte_mkclean(pte_t pte)
177 {
178 	pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
179 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
180 
181 	return pte;
182 }
183 
184 static inline pte_t pte_mkdirty(pte_t pte)
185 {
186 	pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
187 
188 	if (pte_write(pte))
189 		pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
190 
191 	return pte;
192 }
193 
194 static inline pte_t pte_wrprotect(pte_t pte)
195 {
196 	/*
197 	 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
198 	 * clear), set the PTE_DIRTY bit.
199 	 */
200 	if (pte_hw_dirty(pte))
201 		pte = pte_mkdirty(pte);
202 
203 	pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
204 	pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
205 	return pte;
206 }
207 
208 static inline pte_t pte_mkold(pte_t pte)
209 {
210 	return clear_pte_bit(pte, __pgprot(PTE_AF));
211 }
212 
213 static inline pte_t pte_mkyoung(pte_t pte)
214 {
215 	return set_pte_bit(pte, __pgprot(PTE_AF));
216 }
217 
218 static inline pte_t pte_mkspecial(pte_t pte)
219 {
220 	return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
221 }
222 
223 static inline pte_t pte_mkcont(pte_t pte)
224 {
225 	pte = set_pte_bit(pte, __pgprot(PTE_CONT));
226 	return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
227 }
228 
229 static inline pte_t pte_mknoncont(pte_t pte)
230 {
231 	return clear_pte_bit(pte, __pgprot(PTE_CONT));
232 }
233 
234 static inline pte_t pte_mkpresent(pte_t pte)
235 {
236 	return set_pte_bit(pte, __pgprot(PTE_VALID));
237 }
238 
239 static inline pmd_t pmd_mkcont(pmd_t pmd)
240 {
241 	return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
242 }
243 
244 static inline pte_t pte_mkdevmap(pte_t pte)
245 {
246 	return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL));
247 }
248 
249 static inline void set_pte(pte_t *ptep, pte_t pte)
250 {
251 	WRITE_ONCE(*ptep, pte);
252 
253 	/*
254 	 * Only if the new pte is valid and kernel, otherwise TLB maintenance
255 	 * or update_mmu_cache() have the necessary barriers.
256 	 */
257 	if (pte_valid_not_user(pte)) {
258 		dsb(ishst);
259 		isb();
260 	}
261 }
262 
263 extern void __sync_icache_dcache(pte_t pteval);
264 
265 /*
266  * PTE bits configuration in the presence of hardware Dirty Bit Management
267  * (PTE_WRITE == PTE_DBM):
268  *
269  * Dirty  Writable | PTE_RDONLY  PTE_WRITE  PTE_DIRTY (sw)
270  *   0      0      |   1           0          0
271  *   0      1      |   1           1          0
272  *   1      0      |   1           0          1
273  *   1      1      |   0           1          x
274  *
275  * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
276  * the page fault mechanism. Checking the dirty status of a pte becomes:
277  *
278  *   PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
279  */
280 
281 static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep,
282 					   pte_t pte)
283 {
284 	pte_t old_pte;
285 
286 	if (!IS_ENABLED(CONFIG_DEBUG_VM))
287 		return;
288 
289 	old_pte = READ_ONCE(*ptep);
290 
291 	if (!pte_valid(old_pte) || !pte_valid(pte))
292 		return;
293 	if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
294 		return;
295 
296 	/*
297 	 * Check for potential race with hardware updates of the pte
298 	 * (ptep_set_access_flags safely changes valid ptes without going
299 	 * through an invalid entry).
300 	 */
301 	VM_WARN_ONCE(!pte_young(pte),
302 		     "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
303 		     __func__, pte_val(old_pte), pte_val(pte));
304 	VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
305 		     "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
306 		     __func__, pte_val(old_pte), pte_val(pte));
307 }
308 
309 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
310 			      pte_t *ptep, pte_t pte)
311 {
312 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
313 		__sync_icache_dcache(pte);
314 
315 	/*
316 	 * If the PTE would provide user space access to the tags associated
317 	 * with it then ensure that the MTE tags are synchronised.  Although
318 	 * pte_access_permitted() returns false for exec only mappings, they
319 	 * don't expose tags (instruction fetches don't check tags).
320 	 */
321 	if (system_supports_mte() && pte_access_permitted(pte, false) &&
322 	    !pte_special(pte)) {
323 		pte_t old_pte = READ_ONCE(*ptep);
324 		/*
325 		 * We only need to synchronise if the new PTE has tags enabled
326 		 * or if swapping in (in which case another mapping may have
327 		 * set tags in the past even if this PTE isn't tagged).
328 		 * (!pte_none() && !pte_present()) is an open coded version of
329 		 * is_swap_pte()
330 		 */
331 		if (pte_tagged(pte) || (!pte_none(old_pte) && !pte_present(old_pte)))
332 			mte_sync_tags(old_pte, pte);
333 	}
334 
335 	__check_racy_pte_update(mm, ptep, pte);
336 
337 	set_pte(ptep, pte);
338 }
339 
340 /*
341  * Huge pte definitions.
342  */
343 #define pte_mkhuge(pte)		(__pte(pte_val(pte) & ~PTE_TABLE_BIT))
344 
345 /*
346  * Hugetlb definitions.
347  */
348 #define HUGE_MAX_HSTATE		4
349 #define HPAGE_SHIFT		PMD_SHIFT
350 #define HPAGE_SIZE		(_AC(1, UL) << HPAGE_SHIFT)
351 #define HPAGE_MASK		(~(HPAGE_SIZE - 1))
352 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
353 
354 static inline pte_t pgd_pte(pgd_t pgd)
355 {
356 	return __pte(pgd_val(pgd));
357 }
358 
359 static inline pte_t p4d_pte(p4d_t p4d)
360 {
361 	return __pte(p4d_val(p4d));
362 }
363 
364 static inline pte_t pud_pte(pud_t pud)
365 {
366 	return __pte(pud_val(pud));
367 }
368 
369 static inline pud_t pte_pud(pte_t pte)
370 {
371 	return __pud(pte_val(pte));
372 }
373 
374 static inline pmd_t pud_pmd(pud_t pud)
375 {
376 	return __pmd(pud_val(pud));
377 }
378 
379 static inline pte_t pmd_pte(pmd_t pmd)
380 {
381 	return __pte(pmd_val(pmd));
382 }
383 
384 static inline pmd_t pte_pmd(pte_t pte)
385 {
386 	return __pmd(pte_val(pte));
387 }
388 
389 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
390 {
391 	return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT);
392 }
393 
394 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
395 {
396 	return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
397 }
398 
399 #ifdef CONFIG_NUMA_BALANCING
400 /*
401  * See the comment in include/linux/pgtable.h
402  */
403 static inline int pte_protnone(pte_t pte)
404 {
405 	return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE;
406 }
407 
408 static inline int pmd_protnone(pmd_t pmd)
409 {
410 	return pte_protnone(pmd_pte(pmd));
411 }
412 #endif
413 
414 #define pmd_present_invalid(pmd)     (!!(pmd_val(pmd) & PMD_PRESENT_INVALID))
415 
416 static inline int pmd_present(pmd_t pmd)
417 {
418 	return pte_present(pmd_pte(pmd)) || pmd_present_invalid(pmd);
419 }
420 
421 /*
422  * THP definitions.
423  */
424 
425 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
426 static inline int pmd_trans_huge(pmd_t pmd)
427 {
428 	return pmd_val(pmd) && pmd_present(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
429 }
430 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
431 
432 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
433 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
434 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
435 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
436 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
437 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
438 #define pmd_mkwrite(pmd)	pte_pmd(pte_mkwrite(pmd_pte(pmd)))
439 #define pmd_mkclean(pmd)	pte_pmd(pte_mkclean(pmd_pte(pmd)))
440 #define pmd_mkdirty(pmd)	pte_pmd(pte_mkdirty(pmd_pte(pmd)))
441 #define pmd_mkyoung(pmd)	pte_pmd(pte_mkyoung(pmd_pte(pmd)))
442 
443 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
444 {
445 	pmd = set_pmd_bit(pmd, __pgprot(PMD_PRESENT_INVALID));
446 	pmd = clear_pmd_bit(pmd, __pgprot(PMD_SECT_VALID));
447 
448 	return pmd;
449 }
450 
451 #define pmd_thp_or_huge(pmd)	(pmd_huge(pmd) || pmd_trans_huge(pmd))
452 
453 #define pmd_write(pmd)		pte_write(pmd_pte(pmd))
454 
455 #define pmd_mkhuge(pmd)		(__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
456 
457 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
458 #define pmd_devmap(pmd)		pte_devmap(pmd_pte(pmd))
459 #endif
460 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
461 {
462 	return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP)));
463 }
464 
465 #define __pmd_to_phys(pmd)	__pte_to_phys(pmd_pte(pmd))
466 #define __phys_to_pmd_val(phys)	__phys_to_pte_val(phys)
467 #define pmd_pfn(pmd)		((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
468 #define pfn_pmd(pfn,prot)	__pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
469 #define mk_pmd(page,prot)	pfn_pmd(page_to_pfn(page),prot)
470 
471 #define pud_young(pud)		pte_young(pud_pte(pud))
472 #define pud_mkyoung(pud)	pte_pud(pte_mkyoung(pud_pte(pud)))
473 #define pud_write(pud)		pte_write(pud_pte(pud))
474 
475 #define pud_mkhuge(pud)		(__pud(pud_val(pud) & ~PUD_TABLE_BIT))
476 
477 #define __pud_to_phys(pud)	__pte_to_phys(pud_pte(pud))
478 #define __phys_to_pud_val(phys)	__phys_to_pte_val(phys)
479 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
480 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
481 
482 #define set_pmd_at(mm, addr, pmdp, pmd)	set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
483 #define set_pud_at(mm, addr, pudp, pud)	set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud))
484 
485 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
486 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
487 
488 #define __pgd_to_phys(pgd)	__pte_to_phys(pgd_pte(pgd))
489 #define __phys_to_pgd_val(phys)	__phys_to_pte_val(phys)
490 
491 #define __pgprot_modify(prot,mask,bits) \
492 	__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
493 
494 #define pgprot_nx(prot) \
495 	__pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
496 
497 /*
498  * Mark the prot value as uncacheable and unbufferable.
499  */
500 #define pgprot_noncached(prot) \
501 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
502 #define pgprot_writecombine(prot) \
503 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
504 #define pgprot_device(prot) \
505 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
506 #define pgprot_tagged(prot) \
507 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
508 #define pgprot_mhp	pgprot_tagged
509 /*
510  * DMA allocations for non-coherent devices use what the Arm architecture calls
511  * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
512  * and merging of writes.  This is different from "Device-nGnR[nE]" memory which
513  * is intended for MMIO and thus forbids speculation, preserves access size,
514  * requires strict alignment and can also force write responses to come from the
515  * endpoint.
516  */
517 #define pgprot_dmacoherent(prot) \
518 	__pgprot_modify(prot, PTE_ATTRINDX_MASK, \
519 			PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
520 
521 #define __HAVE_PHYS_MEM_ACCESS_PROT
522 struct file;
523 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
524 				     unsigned long size, pgprot_t vma_prot);
525 
526 #define pmd_none(pmd)		(!pmd_val(pmd))
527 
528 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
529 				 PMD_TYPE_TABLE)
530 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
531 				 PMD_TYPE_SECT)
532 #define pmd_leaf(pmd)		pmd_sect(pmd)
533 #define pmd_bad(pmd)		(!pmd_table(pmd))
534 
535 #define pmd_leaf_size(pmd)	(pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
536 #define pte_leaf_size(pte)	(pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
537 
538 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
539 static inline bool pud_sect(pud_t pud) { return false; }
540 static inline bool pud_table(pud_t pud) { return true; }
541 #else
542 #define pud_sect(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
543 				 PUD_TYPE_SECT)
544 #define pud_table(pud)		((pud_val(pud) & PUD_TYPE_MASK) == \
545 				 PUD_TYPE_TABLE)
546 #endif
547 
548 extern pgd_t init_pg_dir[PTRS_PER_PGD];
549 extern pgd_t init_pg_end[];
550 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
551 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
552 extern pgd_t idmap_pg_end[];
553 extern pgd_t tramp_pg_dir[PTRS_PER_PGD];
554 extern pgd_t reserved_pg_dir[PTRS_PER_PGD];
555 
556 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
557 
558 static inline bool in_swapper_pgdir(void *addr)
559 {
560 	return ((unsigned long)addr & PAGE_MASK) ==
561 	        ((unsigned long)swapper_pg_dir & PAGE_MASK);
562 }
563 
564 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
565 {
566 #ifdef __PAGETABLE_PMD_FOLDED
567 	if (in_swapper_pgdir(pmdp)) {
568 		set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
569 		return;
570 	}
571 #endif /* __PAGETABLE_PMD_FOLDED */
572 
573 	WRITE_ONCE(*pmdp, pmd);
574 
575 	if (pmd_valid(pmd)) {
576 		dsb(ishst);
577 		isb();
578 	}
579 }
580 
581 static inline void pmd_clear(pmd_t *pmdp)
582 {
583 	set_pmd(pmdp, __pmd(0));
584 }
585 
586 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
587 {
588 	return __pmd_to_phys(pmd);
589 }
590 
591 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
592 {
593 	return (unsigned long)__va(pmd_page_paddr(pmd));
594 }
595 
596 /* Find an entry in the third-level page table. */
597 #define pte_offset_phys(dir,addr)	(pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
598 
599 #define pte_set_fixmap(addr)		((pte_t *)set_fixmap_offset(FIX_PTE, addr))
600 #define pte_set_fixmap_offset(pmd, addr)	pte_set_fixmap(pte_offset_phys(pmd, addr))
601 #define pte_clear_fixmap()		clear_fixmap(FIX_PTE)
602 
603 #define pmd_page(pmd)			phys_to_page(__pmd_to_phys(pmd))
604 
605 /* use ONLY for statically allocated translation tables */
606 #define pte_offset_kimg(dir,addr)	((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
607 
608 /*
609  * Conversion functions: convert a page and protection to a page entry,
610  * and a page entry and page directory to the page they refer to.
611  */
612 #define mk_pte(page,prot)	pfn_pte(page_to_pfn(page),prot)
613 
614 #if CONFIG_PGTABLE_LEVELS > 2
615 
616 #define pmd_ERROR(e)	\
617 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
618 
619 #define pud_none(pud)		(!pud_val(pud))
620 #define pud_bad(pud)		(!pud_table(pud))
621 #define pud_present(pud)	pte_present(pud_pte(pud))
622 #define pud_leaf(pud)		pud_sect(pud)
623 #define pud_valid(pud)		pte_valid(pud_pte(pud))
624 
625 static inline void set_pud(pud_t *pudp, pud_t pud)
626 {
627 #ifdef __PAGETABLE_PUD_FOLDED
628 	if (in_swapper_pgdir(pudp)) {
629 		set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
630 		return;
631 	}
632 #endif /* __PAGETABLE_PUD_FOLDED */
633 
634 	WRITE_ONCE(*pudp, pud);
635 
636 	if (pud_valid(pud)) {
637 		dsb(ishst);
638 		isb();
639 	}
640 }
641 
642 static inline void pud_clear(pud_t *pudp)
643 {
644 	set_pud(pudp, __pud(0));
645 }
646 
647 static inline phys_addr_t pud_page_paddr(pud_t pud)
648 {
649 	return __pud_to_phys(pud);
650 }
651 
652 static inline pmd_t *pud_pgtable(pud_t pud)
653 {
654 	return (pmd_t *)__va(pud_page_paddr(pud));
655 }
656 
657 /* Find an entry in the second-level page table. */
658 #define pmd_offset_phys(dir, addr)	(pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
659 
660 #define pmd_set_fixmap(addr)		((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
661 #define pmd_set_fixmap_offset(pud, addr)	pmd_set_fixmap(pmd_offset_phys(pud, addr))
662 #define pmd_clear_fixmap()		clear_fixmap(FIX_PMD)
663 
664 #define pud_page(pud)			phys_to_page(__pud_to_phys(pud))
665 
666 /* use ONLY for statically allocated translation tables */
667 #define pmd_offset_kimg(dir,addr)	((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
668 
669 #else
670 
671 #define pud_page_paddr(pud)	({ BUILD_BUG(); 0; })
672 
673 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
674 #define pmd_set_fixmap(addr)		NULL
675 #define pmd_set_fixmap_offset(pudp, addr)	((pmd_t *)pudp)
676 #define pmd_clear_fixmap()
677 
678 #define pmd_offset_kimg(dir,addr)	((pmd_t *)dir)
679 
680 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
681 
682 #if CONFIG_PGTABLE_LEVELS > 3
683 
684 #define pud_ERROR(e)	\
685 	pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
686 
687 #define p4d_none(p4d)		(!p4d_val(p4d))
688 #define p4d_bad(p4d)		(!(p4d_val(p4d) & 2))
689 #define p4d_present(p4d)	(p4d_val(p4d))
690 
691 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
692 {
693 	if (in_swapper_pgdir(p4dp)) {
694 		set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
695 		return;
696 	}
697 
698 	WRITE_ONCE(*p4dp, p4d);
699 	dsb(ishst);
700 	isb();
701 }
702 
703 static inline void p4d_clear(p4d_t *p4dp)
704 {
705 	set_p4d(p4dp, __p4d(0));
706 }
707 
708 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
709 {
710 	return __p4d_to_phys(p4d);
711 }
712 
713 static inline pud_t *p4d_pgtable(p4d_t p4d)
714 {
715 	return (pud_t *)__va(p4d_page_paddr(p4d));
716 }
717 
718 /* Find an entry in the first-level page table. */
719 #define pud_offset_phys(dir, addr)	(p4d_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t))
720 
721 #define pud_set_fixmap(addr)		((pud_t *)set_fixmap_offset(FIX_PUD, addr))
722 #define pud_set_fixmap_offset(p4d, addr)	pud_set_fixmap(pud_offset_phys(p4d, addr))
723 #define pud_clear_fixmap()		clear_fixmap(FIX_PUD)
724 
725 #define p4d_page(p4d)		pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
726 
727 /* use ONLY for statically allocated translation tables */
728 #define pud_offset_kimg(dir,addr)	((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr))))
729 
730 #else
731 
732 #define p4d_page_paddr(p4d)	({ BUILD_BUG(); 0;})
733 #define pgd_page_paddr(pgd)	({ BUILD_BUG(); 0;})
734 
735 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
736 #define pud_set_fixmap(addr)		NULL
737 #define pud_set_fixmap_offset(pgdp, addr)	((pud_t *)pgdp)
738 #define pud_clear_fixmap()
739 
740 #define pud_offset_kimg(dir,addr)	((pud_t *)dir)
741 
742 #endif  /* CONFIG_PGTABLE_LEVELS > 3 */
743 
744 #define pgd_ERROR(e)	\
745 	pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
746 
747 #define pgd_set_fixmap(addr)	((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
748 #define pgd_clear_fixmap()	clear_fixmap(FIX_PGD)
749 
750 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
751 {
752 	/*
753 	 * Normal and Normal-Tagged are two different memory types and indices
754 	 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
755 	 */
756 	const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
757 			      PTE_PROT_NONE | PTE_VALID | PTE_WRITE | PTE_GP |
758 			      PTE_ATTRINDX_MASK;
759 	/* preserve the hardware dirty information */
760 	if (pte_hw_dirty(pte))
761 		pte = pte_mkdirty(pte);
762 	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
763 	return pte;
764 }
765 
766 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
767 {
768 	return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
769 }
770 
771 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
772 extern int ptep_set_access_flags(struct vm_area_struct *vma,
773 				 unsigned long address, pte_t *ptep,
774 				 pte_t entry, int dirty);
775 
776 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
777 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
778 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
779 					unsigned long address, pmd_t *pmdp,
780 					pmd_t entry, int dirty)
781 {
782 	return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
783 }
784 
785 static inline int pud_devmap(pud_t pud)
786 {
787 	return 0;
788 }
789 
790 static inline int pgd_devmap(pgd_t pgd)
791 {
792 	return 0;
793 }
794 #endif
795 
796 /*
797  * Atomic pte/pmd modifications.
798  */
799 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
800 static inline int __ptep_test_and_clear_young(pte_t *ptep)
801 {
802 	pte_t old_pte, pte;
803 
804 	pte = READ_ONCE(*ptep);
805 	do {
806 		old_pte = pte;
807 		pte = pte_mkold(pte);
808 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
809 					       pte_val(old_pte), pte_val(pte));
810 	} while (pte_val(pte) != pte_val(old_pte));
811 
812 	return pte_young(pte);
813 }
814 
815 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
816 					    unsigned long address,
817 					    pte_t *ptep)
818 {
819 	return __ptep_test_and_clear_young(ptep);
820 }
821 
822 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
823 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
824 					 unsigned long address, pte_t *ptep)
825 {
826 	int young = ptep_test_and_clear_young(vma, address, ptep);
827 
828 	if (young) {
829 		/*
830 		 * We can elide the trailing DSB here since the worst that can
831 		 * happen is that a CPU continues to use the young entry in its
832 		 * TLB and we mistakenly reclaim the associated page. The
833 		 * window for such an event is bounded by the next
834 		 * context-switch, which provides a DSB to complete the TLB
835 		 * invalidation.
836 		 */
837 		flush_tlb_page_nosync(vma, address);
838 	}
839 
840 	return young;
841 }
842 
843 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
844 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
845 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
846 					    unsigned long address,
847 					    pmd_t *pmdp)
848 {
849 	return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
850 }
851 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
852 
853 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
854 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
855 				       unsigned long address, pte_t *ptep)
856 {
857 	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
858 }
859 
860 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
861 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
862 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
863 					    unsigned long address, pmd_t *pmdp)
864 {
865 	return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
866 }
867 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
868 
869 /*
870  * ptep_set_wrprotect - mark read-only while trasferring potential hardware
871  * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
872  */
873 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
874 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
875 {
876 	pte_t old_pte, pte;
877 
878 	pte = READ_ONCE(*ptep);
879 	do {
880 		old_pte = pte;
881 		pte = pte_wrprotect(pte);
882 		pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
883 					       pte_val(old_pte), pte_val(pte));
884 	} while (pte_val(pte) != pte_val(old_pte));
885 }
886 
887 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
888 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
889 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
890 				      unsigned long address, pmd_t *pmdp)
891 {
892 	ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
893 }
894 
895 #define pmdp_establish pmdp_establish
896 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
897 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
898 {
899 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
900 }
901 #endif
902 
903 /*
904  * Encode and decode a swap entry:
905  *	bits 0-1:	present (must be zero)
906  *	bits 2-7:	swap type
907  *	bits 8-57:	swap offset
908  *	bit  58:	PTE_PROT_NONE (must be zero)
909  */
910 #define __SWP_TYPE_SHIFT	2
911 #define __SWP_TYPE_BITS		6
912 #define __SWP_OFFSET_BITS	50
913 #define __SWP_TYPE_MASK		((1 << __SWP_TYPE_BITS) - 1)
914 #define __SWP_OFFSET_SHIFT	(__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
915 #define __SWP_OFFSET_MASK	((1UL << __SWP_OFFSET_BITS) - 1)
916 
917 #define __swp_type(x)		(((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
918 #define __swp_offset(x)		(((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
919 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
920 
921 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
922 #define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
923 
924 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
925 #define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val(pmd) })
926 #define __swp_entry_to_pmd(swp)		__pmd((swp).val)
927 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
928 
929 /*
930  * Ensure that there are not more swap files than can be encoded in the kernel
931  * PTEs.
932  */
933 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
934 
935 extern int kern_addr_valid(unsigned long addr);
936 
937 #ifdef CONFIG_ARM64_MTE
938 
939 #define __HAVE_ARCH_PREPARE_TO_SWAP
940 static inline int arch_prepare_to_swap(struct page *page)
941 {
942 	if (system_supports_mte())
943 		return mte_save_tags(page);
944 	return 0;
945 }
946 
947 #define __HAVE_ARCH_SWAP_INVALIDATE
948 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
949 {
950 	if (system_supports_mte())
951 		mte_invalidate_tags(type, offset);
952 }
953 
954 static inline void arch_swap_invalidate_area(int type)
955 {
956 	if (system_supports_mte())
957 		mte_invalidate_tags_area(type);
958 }
959 
960 #define __HAVE_ARCH_SWAP_RESTORE
961 static inline void arch_swap_restore(swp_entry_t entry, struct page *page)
962 {
963 	if (system_supports_mte() && mte_restore_tags(entry, page))
964 		set_bit(PG_mte_tagged, &page->flags);
965 }
966 
967 #endif /* CONFIG_ARM64_MTE */
968 
969 /*
970  * On AArch64, the cache coherency is handled via the set_pte_at() function.
971  */
972 static inline void update_mmu_cache(struct vm_area_struct *vma,
973 				    unsigned long addr, pte_t *ptep)
974 {
975 	/*
976 	 * We don't do anything here, so there's a very small chance of
977 	 * us retaking a user fault which we just fixed up. The alternative
978 	 * is doing a dsb(ishst), but that penalises the fastpath.
979 	 */
980 }
981 
982 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
983 
984 #ifdef CONFIG_ARM64_PA_BITS_52
985 #define phys_to_ttbr(addr)	(((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
986 #else
987 #define phys_to_ttbr(addr)	(addr)
988 #endif
989 
990 /*
991  * On arm64 without hardware Access Flag, copying from user will fail because
992  * the pte is old and cannot be marked young. So we always end up with zeroed
993  * page after fork() + CoW for pfn mappings. We don't always have a
994  * hardware-managed access flag on arm64.
995  */
996 static inline bool arch_faults_on_old_pte(void)
997 {
998 	WARN_ON(preemptible());
999 
1000 	return !cpu_has_hw_af();
1001 }
1002 #define arch_faults_on_old_pte		arch_faults_on_old_pte
1003 
1004 /*
1005  * Experimentally, it's cheap to set the access flag in hardware and we
1006  * benefit from prefaulting mappings as 'old' to start with.
1007  */
1008 static inline bool arch_wants_old_prefaulted_pte(void)
1009 {
1010 	return !arch_faults_on_old_pte();
1011 }
1012 #define arch_wants_old_prefaulted_pte	arch_wants_old_prefaulted_pte
1013 
1014 static inline pgprot_t arch_filter_pgprot(pgprot_t prot)
1015 {
1016 	if (cpus_have_const_cap(ARM64_HAS_EPAN))
1017 		return prot;
1018 
1019 	if (pgprot_val(prot) != pgprot_val(PAGE_EXECONLY))
1020 		return prot;
1021 
1022 	return PAGE_READONLY_EXEC;
1023 }
1024 
1025 
1026 #endif /* !__ASSEMBLY__ */
1027 
1028 #endif /* __ASM_PGTABLE_H */
1029