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
__pte_to_phys(pte_t pte)70 static inline phys_addr_t __pte_to_phys(pte_t pte)
71 {
72 return (pte_val(pte) & PTE_ADDR_LOW) |
73 ((pte_val(pte) & PTE_ADDR_HIGH) << 36);
74 }
__phys_to_pte_val(phys_addr_t phys)75 static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
76 {
77 return (phys | (phys >> 36)) & PTE_ADDR_MASK;
78 }
79 #else
80 #define __pte_to_phys(pte) (pte_val(pte) & PTE_ADDR_MASK)
81 #define __phys_to_pte_val(phys) (phys)
82 #endif
83
84 #define pte_pfn(pte) (__pte_to_phys(pte) >> PAGE_SHIFT)
85 #define pfn_pte(pfn,prot) \
86 __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
87
88 #define pte_none(pte) (!pte_val(pte))
89 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0))
90 #define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
91
92 /*
93 * The following only work if pte_present(). Undefined behaviour otherwise.
94 */
95 #define pte_present(pte) (!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
96 #define pte_young(pte) (!!(pte_val(pte) & PTE_AF))
97 #define pte_special(pte) (!!(pte_val(pte) & PTE_SPECIAL))
98 #define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE))
99 #define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN))
100 #define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT))
101 #define pte_devmap(pte) (!!(pte_val(pte) & PTE_DEVMAP))
102 #define pte_tagged(pte) ((pte_val(pte) & PTE_ATTRINDX_MASK) == \
103 PTE_ATTRINDX(MT_NORMAL_TAGGED))
104
105 #define pte_cont_addr_end(addr, end) \
106 ({ unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK; \
107 (__boundary - 1 < (end) - 1) ? __boundary : (end); \
108 })
109
110 #define pmd_cont_addr_end(addr, end) \
111 ({ unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK; \
112 (__boundary - 1 < (end) - 1) ? __boundary : (end); \
113 })
114
115 #define pte_hw_dirty(pte) (pte_write(pte) && !(pte_val(pte) & PTE_RDONLY))
116 #define pte_sw_dirty(pte) (!!(pte_val(pte) & PTE_DIRTY))
117 #define pte_dirty(pte) (pte_sw_dirty(pte) || pte_hw_dirty(pte))
118
119 #define pte_valid(pte) (!!(pte_val(pte) & PTE_VALID))
120 /*
121 * Execute-only user mappings do not have the PTE_USER bit set. All valid
122 * kernel mappings have the PTE_UXN bit set.
123 */
124 #define pte_valid_not_user(pte) \
125 ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
126 /*
127 * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
128 * so that we don't erroneously return false for pages that have been
129 * remapped as PROT_NONE but are yet to be flushed from the TLB.
130 * Note that we can't make any assumptions based on the state of the access
131 * flag, since ptep_clear_flush_young() elides a DSB when invalidating the
132 * TLB.
133 */
134 #define pte_accessible(mm, pte) \
135 (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte))
136
137 /*
138 * p??_access_permitted() is true for valid user mappings (PTE_USER
139 * bit set, subject to the write permission check). For execute-only
140 * mappings, like PROT_EXEC with EPAN (both PTE_USER and PTE_UXN bits
141 * not set) must return false. PROT_NONE mappings do not have the
142 * PTE_VALID bit set.
143 */
144 #define pte_access_permitted(pte, write) \
145 (((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) && (!(write) || pte_write(pte)))
146 #define pmd_access_permitted(pmd, write) \
147 (pte_access_permitted(pmd_pte(pmd), (write)))
148 #define pud_access_permitted(pud, write) \
149 (pte_access_permitted(pud_pte(pud), (write)))
150
clear_pte_bit(pte_t pte,pgprot_t prot)151 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
152 {
153 pte_val(pte) &= ~pgprot_val(prot);
154 return pte;
155 }
156
set_pte_bit(pte_t pte,pgprot_t prot)157 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
158 {
159 pte_val(pte) |= pgprot_val(prot);
160 return pte;
161 }
162
clear_pmd_bit(pmd_t pmd,pgprot_t prot)163 static inline pmd_t clear_pmd_bit(pmd_t pmd, pgprot_t prot)
164 {
165 pmd_val(pmd) &= ~pgprot_val(prot);
166 return pmd;
167 }
168
set_pmd_bit(pmd_t pmd,pgprot_t prot)169 static inline pmd_t set_pmd_bit(pmd_t pmd, pgprot_t prot)
170 {
171 pmd_val(pmd) |= pgprot_val(prot);
172 return pmd;
173 }
174
pte_mkwrite(pte_t pte)175 static inline pte_t pte_mkwrite(pte_t pte)
176 {
177 pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
178 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
179 return pte;
180 }
181
pte_mkclean(pte_t pte)182 static inline pte_t pte_mkclean(pte_t pte)
183 {
184 pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
185 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
186
187 return pte;
188 }
189
pte_mkdirty(pte_t pte)190 static inline pte_t pte_mkdirty(pte_t pte)
191 {
192 pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
193
194 if (pte_write(pte))
195 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
196
197 return pte;
198 }
199
pte_wrprotect(pte_t pte)200 static inline pte_t pte_wrprotect(pte_t pte)
201 {
202 /*
203 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
204 * clear), set the PTE_DIRTY bit.
205 */
206 if (pte_hw_dirty(pte))
207 pte = pte_mkdirty(pte);
208
209 pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
210 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
211 return pte;
212 }
213
pte_mkold(pte_t pte)214 static inline pte_t pte_mkold(pte_t pte)
215 {
216 return clear_pte_bit(pte, __pgprot(PTE_AF));
217 }
218
pte_mkyoung(pte_t pte)219 static inline pte_t pte_mkyoung(pte_t pte)
220 {
221 return set_pte_bit(pte, __pgprot(PTE_AF));
222 }
223
pte_mkspecial(pte_t pte)224 static inline pte_t pte_mkspecial(pte_t pte)
225 {
226 return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
227 }
228
pte_mkcont(pte_t pte)229 static inline pte_t pte_mkcont(pte_t pte)
230 {
231 pte = set_pte_bit(pte, __pgprot(PTE_CONT));
232 return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
233 }
234
pte_mknoncont(pte_t pte)235 static inline pte_t pte_mknoncont(pte_t pte)
236 {
237 return clear_pte_bit(pte, __pgprot(PTE_CONT));
238 }
239
pte_mkpresent(pte_t pte)240 static inline pte_t pte_mkpresent(pte_t pte)
241 {
242 return set_pte_bit(pte, __pgprot(PTE_VALID));
243 }
244
pmd_mkcont(pmd_t pmd)245 static inline pmd_t pmd_mkcont(pmd_t pmd)
246 {
247 return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
248 }
249
pte_mkdevmap(pte_t pte)250 static inline pte_t pte_mkdevmap(pte_t pte)
251 {
252 return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL));
253 }
254
set_pte(pte_t * ptep,pte_t pte)255 static inline void set_pte(pte_t *ptep, pte_t pte)
256 {
257 WRITE_ONCE(*ptep, pte);
258
259 /*
260 * Only if the new pte is valid and kernel, otherwise TLB maintenance
261 * or update_mmu_cache() have the necessary barriers.
262 */
263 if (pte_valid_not_user(pte)) {
264 dsb(ishst);
265 isb();
266 }
267 }
268
269 extern void __sync_icache_dcache(pte_t pteval);
270
271 /*
272 * PTE bits configuration in the presence of hardware Dirty Bit Management
273 * (PTE_WRITE == PTE_DBM):
274 *
275 * Dirty Writable | PTE_RDONLY PTE_WRITE PTE_DIRTY (sw)
276 * 0 0 | 1 0 0
277 * 0 1 | 1 1 0
278 * 1 0 | 1 0 1
279 * 1 1 | 0 1 x
280 *
281 * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
282 * the page fault mechanism. Checking the dirty status of a pte becomes:
283 *
284 * PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
285 */
286
__check_racy_pte_update(struct mm_struct * mm,pte_t * ptep,pte_t pte)287 static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep,
288 pte_t pte)
289 {
290 pte_t old_pte;
291
292 if (!IS_ENABLED(CONFIG_DEBUG_VM))
293 return;
294
295 old_pte = READ_ONCE(*ptep);
296
297 if (!pte_valid(old_pte) || !pte_valid(pte))
298 return;
299 if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
300 return;
301
302 /*
303 * Check for potential race with hardware updates of the pte
304 * (ptep_set_access_flags safely changes valid ptes without going
305 * through an invalid entry).
306 */
307 VM_WARN_ONCE(!pte_young(pte),
308 "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
309 __func__, pte_val(old_pte), pte_val(pte));
310 VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
311 "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
312 __func__, pte_val(old_pte), pte_val(pte));
313 }
314
set_pte_at(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pte_t pte)315 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
316 pte_t *ptep, pte_t pte)
317 {
318 if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
319 __sync_icache_dcache(pte);
320
321 /*
322 * If the PTE would provide user space access to the tags associated
323 * with it then ensure that the MTE tags are synchronised. Although
324 * pte_access_permitted() returns false for exec only mappings, they
325 * don't expose tags (instruction fetches don't check tags).
326 */
327 if (system_supports_mte() && pte_access_permitted(pte, false) &&
328 !pte_special(pte)) {
329 pte_t old_pte = READ_ONCE(*ptep);
330 /*
331 * We only need to synchronise if the new PTE has tags enabled
332 * or if swapping in (in which case another mapping may have
333 * set tags in the past even if this PTE isn't tagged).
334 * (!pte_none() && !pte_present()) is an open coded version of
335 * is_swap_pte()
336 */
337 if (pte_tagged(pte) || (!pte_none(old_pte) && !pte_present(old_pte)))
338 mte_sync_tags(old_pte, pte);
339 }
340
341 __check_racy_pte_update(mm, ptep, pte);
342
343 set_pte(ptep, pte);
344 }
345
346 /*
347 * Huge pte definitions.
348 */
349 #define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT))
350
351 /*
352 * Hugetlb definitions.
353 */
354 #define HUGE_MAX_HSTATE 4
355 #define HPAGE_SHIFT PMD_SHIFT
356 #define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT)
357 #define HPAGE_MASK (~(HPAGE_SIZE - 1))
358 #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
359
pgd_pte(pgd_t pgd)360 static inline pte_t pgd_pte(pgd_t pgd)
361 {
362 return __pte(pgd_val(pgd));
363 }
364
p4d_pte(p4d_t p4d)365 static inline pte_t p4d_pte(p4d_t p4d)
366 {
367 return __pte(p4d_val(p4d));
368 }
369
pud_pte(pud_t pud)370 static inline pte_t pud_pte(pud_t pud)
371 {
372 return __pte(pud_val(pud));
373 }
374
pte_pud(pte_t pte)375 static inline pud_t pte_pud(pte_t pte)
376 {
377 return __pud(pte_val(pte));
378 }
379
pud_pmd(pud_t pud)380 static inline pmd_t pud_pmd(pud_t pud)
381 {
382 return __pmd(pud_val(pud));
383 }
384
pmd_pte(pmd_t pmd)385 static inline pte_t pmd_pte(pmd_t pmd)
386 {
387 return __pte(pmd_val(pmd));
388 }
389
pte_pmd(pte_t pte)390 static inline pmd_t pte_pmd(pte_t pte)
391 {
392 return __pmd(pte_val(pte));
393 }
394
mk_pud_sect_prot(pgprot_t prot)395 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
396 {
397 return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT);
398 }
399
mk_pmd_sect_prot(pgprot_t prot)400 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
401 {
402 return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
403 }
404
405 #ifdef CONFIG_NUMA_BALANCING
406 /*
407 * See the comment in include/linux/pgtable.h
408 */
pte_protnone(pte_t pte)409 static inline int pte_protnone(pte_t pte)
410 {
411 return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE;
412 }
413
pmd_protnone(pmd_t pmd)414 static inline int pmd_protnone(pmd_t pmd)
415 {
416 return pte_protnone(pmd_pte(pmd));
417 }
418 #endif
419
420 #define pmd_present_invalid(pmd) (!!(pmd_val(pmd) & PMD_PRESENT_INVALID))
421
pmd_present(pmd_t pmd)422 static inline int pmd_present(pmd_t pmd)
423 {
424 return pte_present(pmd_pte(pmd)) || pmd_present_invalid(pmd);
425 }
426
427 /*
428 * THP definitions.
429 */
430
431 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
pmd_trans_huge(pmd_t pmd)432 static inline int pmd_trans_huge(pmd_t pmd)
433 {
434 return pmd_val(pmd) && pmd_present(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
435 }
436 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
437
438 #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd))
439 #define pmd_young(pmd) pte_young(pmd_pte(pmd))
440 #define pmd_valid(pmd) pte_valid(pmd_pte(pmd))
441 #define pmd_cont(pmd) pte_cont(pmd_pte(pmd))
442 #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd)))
443 #define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd)))
444 #define pmd_mkwrite(pmd) pte_pmd(pte_mkwrite(pmd_pte(pmd)))
445 #define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd)))
446 #define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd)))
447 #define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd)))
448
pmd_mkinvalid(pmd_t pmd)449 static inline pmd_t pmd_mkinvalid(pmd_t pmd)
450 {
451 pmd = set_pmd_bit(pmd, __pgprot(PMD_PRESENT_INVALID));
452 pmd = clear_pmd_bit(pmd, __pgprot(PMD_SECT_VALID));
453
454 return pmd;
455 }
456
457 #define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd))
458
459 #define pmd_write(pmd) pte_write(pmd_pte(pmd))
460
461 #define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
462
463 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
464 #define pmd_devmap(pmd) pte_devmap(pmd_pte(pmd))
465 #endif
pmd_mkdevmap(pmd_t pmd)466 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
467 {
468 return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP)));
469 }
470
471 #define __pmd_to_phys(pmd) __pte_to_phys(pmd_pte(pmd))
472 #define __phys_to_pmd_val(phys) __phys_to_pte_val(phys)
473 #define pmd_pfn(pmd) ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
474 #define pfn_pmd(pfn,prot) __pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
475 #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot)
476
477 #define pud_young(pud) pte_young(pud_pte(pud))
478 #define pud_mkyoung(pud) pte_pud(pte_mkyoung(pud_pte(pud)))
479 #define pud_write(pud) pte_write(pud_pte(pud))
480
481 #define pud_mkhuge(pud) (__pud(pud_val(pud) & ~PUD_TABLE_BIT))
482
483 #define __pud_to_phys(pud) __pte_to_phys(pud_pte(pud))
484 #define __phys_to_pud_val(phys) __phys_to_pte_val(phys)
485 #define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
486 #define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
487
488 #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
489 #define set_pud_at(mm, addr, pudp, pud) set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud))
490
491 #define __p4d_to_phys(p4d) __pte_to_phys(p4d_pte(p4d))
492 #define __phys_to_p4d_val(phys) __phys_to_pte_val(phys)
493
494 #define __pgd_to_phys(pgd) __pte_to_phys(pgd_pte(pgd))
495 #define __phys_to_pgd_val(phys) __phys_to_pte_val(phys)
496
497 #define __pgprot_modify(prot,mask,bits) \
498 __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
499
500 #define pgprot_nx(prot) \
501 __pgprot_modify(prot, PTE_MAYBE_GP, PTE_PXN)
502
503 /*
504 * Mark the prot value as uncacheable and unbufferable.
505 */
506 #define pgprot_noncached(prot) \
507 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
508 #define pgprot_writecombine(prot) \
509 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
510 #define pgprot_device(prot) \
511 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
512 #define pgprot_tagged(prot) \
513 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_TAGGED))
514 #define pgprot_mhp pgprot_tagged
515 /*
516 * DMA allocations for non-coherent devices use what the Arm architecture calls
517 * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
518 * and merging of writes. This is different from "Device-nGnR[nE]" memory which
519 * is intended for MMIO and thus forbids speculation, preserves access size,
520 * requires strict alignment and can also force write responses to come from the
521 * endpoint.
522 */
523 #define pgprot_dmacoherent(prot) \
524 __pgprot_modify(prot, PTE_ATTRINDX_MASK, \
525 PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
526
527 #define __HAVE_PHYS_MEM_ACCESS_PROT
528 struct file;
529 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
530 unsigned long size, pgprot_t vma_prot);
531
532 #define pmd_none(pmd) (!pmd_val(pmd))
533
534 #define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
535 PMD_TYPE_TABLE)
536 #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
537 PMD_TYPE_SECT)
538 #define pmd_leaf(pmd) pmd_sect(pmd)
539 #define pmd_bad(pmd) (!pmd_table(pmd))
540
541 #define pmd_leaf_size(pmd) (pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
542 #define pte_leaf_size(pte) (pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE)
543
544 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
pud_sect(pud_t pud)545 static inline bool pud_sect(pud_t pud) { return false; }
pud_table(pud_t pud)546 static inline bool pud_table(pud_t pud) { return true; }
547 #else
548 #define pud_sect(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \
549 PUD_TYPE_SECT)
550 #define pud_table(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \
551 PUD_TYPE_TABLE)
552 #endif
553
554 extern pgd_t init_pg_dir[PTRS_PER_PGD];
555 extern pgd_t init_pg_end[];
556 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
557 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
558 extern pgd_t idmap_pg_end[];
559 extern pgd_t tramp_pg_dir[PTRS_PER_PGD];
560 extern pgd_t reserved_pg_dir[PTRS_PER_PGD];
561
562 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
563
in_swapper_pgdir(void * addr)564 static inline bool in_swapper_pgdir(void *addr)
565 {
566 return ((unsigned long)addr & PAGE_MASK) ==
567 ((unsigned long)swapper_pg_dir & PAGE_MASK);
568 }
569
set_pmd(pmd_t * pmdp,pmd_t pmd)570 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
571 {
572 #ifdef __PAGETABLE_PMD_FOLDED
573 if (in_swapper_pgdir(pmdp)) {
574 set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
575 return;
576 }
577 #endif /* __PAGETABLE_PMD_FOLDED */
578
579 WRITE_ONCE(*pmdp, pmd);
580
581 if (pmd_valid(pmd)) {
582 dsb(ishst);
583 isb();
584 }
585 }
586
pmd_clear(pmd_t * pmdp)587 static inline void pmd_clear(pmd_t *pmdp)
588 {
589 set_pmd(pmdp, __pmd(0));
590 }
591
pmd_page_paddr(pmd_t pmd)592 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
593 {
594 return __pmd_to_phys(pmd);
595 }
596
pmd_page_vaddr(pmd_t pmd)597 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
598 {
599 return (unsigned long)__va(pmd_page_paddr(pmd));
600 }
601
602 /* Find an entry in the third-level page table. */
603 #define pte_offset_phys(dir,addr) (pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
604
605 #define pte_set_fixmap(addr) ((pte_t *)set_fixmap_offset(FIX_PTE, addr))
606 #define pte_set_fixmap_offset(pmd, addr) pte_set_fixmap(pte_offset_phys(pmd, addr))
607 #define pte_clear_fixmap() clear_fixmap(FIX_PTE)
608
609 #define pmd_page(pmd) phys_to_page(__pmd_to_phys(pmd))
610
611 /* use ONLY for statically allocated translation tables */
612 #define pte_offset_kimg(dir,addr) ((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
613
614 /*
615 * Conversion functions: convert a page and protection to a page entry,
616 * and a page entry and page directory to the page they refer to.
617 */
618 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page),prot)
619
620 #if CONFIG_PGTABLE_LEVELS > 2
621
622 #define pmd_ERROR(e) \
623 pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
624
625 #define pud_none(pud) (!pud_val(pud))
626 #define pud_bad(pud) (!pud_table(pud))
627 #define pud_present(pud) pte_present(pud_pte(pud))
628 #define pud_leaf(pud) pud_sect(pud)
629 #define pud_valid(pud) pte_valid(pud_pte(pud))
630
set_pud(pud_t * pudp,pud_t pud)631 static inline void set_pud(pud_t *pudp, pud_t pud)
632 {
633 #ifdef __PAGETABLE_PUD_FOLDED
634 if (in_swapper_pgdir(pudp)) {
635 set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
636 return;
637 }
638 #endif /* __PAGETABLE_PUD_FOLDED */
639
640 WRITE_ONCE(*pudp, pud);
641
642 if (pud_valid(pud)) {
643 dsb(ishst);
644 isb();
645 }
646 }
647
pud_clear(pud_t * pudp)648 static inline void pud_clear(pud_t *pudp)
649 {
650 set_pud(pudp, __pud(0));
651 }
652
pud_page_paddr(pud_t pud)653 static inline phys_addr_t pud_page_paddr(pud_t pud)
654 {
655 return __pud_to_phys(pud);
656 }
657
pud_pgtable(pud_t pud)658 static inline pmd_t *pud_pgtable(pud_t pud)
659 {
660 return (pmd_t *)__va(pud_page_paddr(pud));
661 }
662
663 /* Find an entry in the second-level page table. */
664 #define pmd_offset_phys(dir, addr) (pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
665
666 #define pmd_set_fixmap(addr) ((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
667 #define pmd_set_fixmap_offset(pud, addr) pmd_set_fixmap(pmd_offset_phys(pud, addr))
668 #define pmd_clear_fixmap() clear_fixmap(FIX_PMD)
669
670 #define pud_page(pud) phys_to_page(__pud_to_phys(pud))
671
672 /* use ONLY for statically allocated translation tables */
673 #define pmd_offset_kimg(dir,addr) ((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
674
675 #else
676
677 #define pud_page_paddr(pud) ({ BUILD_BUG(); 0; })
678
679 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
680 #define pmd_set_fixmap(addr) NULL
681 #define pmd_set_fixmap_offset(pudp, addr) ((pmd_t *)pudp)
682 #define pmd_clear_fixmap()
683
684 #define pmd_offset_kimg(dir,addr) ((pmd_t *)dir)
685
686 #endif /* CONFIG_PGTABLE_LEVELS > 2 */
687
688 #if CONFIG_PGTABLE_LEVELS > 3
689
690 #define pud_ERROR(e) \
691 pr_err("%s:%d: bad pud %016llx.\n", __FILE__, __LINE__, pud_val(e))
692
693 #define p4d_none(p4d) (!p4d_val(p4d))
694 #define p4d_bad(p4d) (!(p4d_val(p4d) & 2))
695 #define p4d_present(p4d) (p4d_val(p4d))
696
set_p4d(p4d_t * p4dp,p4d_t p4d)697 static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
698 {
699 if (in_swapper_pgdir(p4dp)) {
700 set_swapper_pgd((pgd_t *)p4dp, __pgd(p4d_val(p4d)));
701 return;
702 }
703
704 WRITE_ONCE(*p4dp, p4d);
705 dsb(ishst);
706 isb();
707 }
708
p4d_clear(p4d_t * p4dp)709 static inline void p4d_clear(p4d_t *p4dp)
710 {
711 set_p4d(p4dp, __p4d(0));
712 }
713
p4d_page_paddr(p4d_t p4d)714 static inline phys_addr_t p4d_page_paddr(p4d_t p4d)
715 {
716 return __p4d_to_phys(p4d);
717 }
718
p4d_pgtable(p4d_t p4d)719 static inline pud_t *p4d_pgtable(p4d_t p4d)
720 {
721 return (pud_t *)__va(p4d_page_paddr(p4d));
722 }
723
724 /* Find an entry in the first-level page table. */
725 #define pud_offset_phys(dir, addr) (p4d_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t))
726
727 #define pud_set_fixmap(addr) ((pud_t *)set_fixmap_offset(FIX_PUD, addr))
728 #define pud_set_fixmap_offset(p4d, addr) pud_set_fixmap(pud_offset_phys(p4d, addr))
729 #define pud_clear_fixmap() clear_fixmap(FIX_PUD)
730
731 #define p4d_page(p4d) pfn_to_page(__phys_to_pfn(__p4d_to_phys(p4d)))
732
733 /* use ONLY for statically allocated translation tables */
734 #define pud_offset_kimg(dir,addr) ((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr))))
735
736 #else
737
738 #define p4d_page_paddr(p4d) ({ BUILD_BUG(); 0;})
739 #define pgd_page_paddr(pgd) ({ BUILD_BUG(); 0;})
740
741 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
742 #define pud_set_fixmap(addr) NULL
743 #define pud_set_fixmap_offset(pgdp, addr) ((pud_t *)pgdp)
744 #define pud_clear_fixmap()
745
746 #define pud_offset_kimg(dir,addr) ((pud_t *)dir)
747
748 #endif /* CONFIG_PGTABLE_LEVELS > 3 */
749
750 #define pgd_ERROR(e) \
751 pr_err("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
752
753 #define pgd_set_fixmap(addr) ((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
754 #define pgd_clear_fixmap() clear_fixmap(FIX_PGD)
755
pte_modify(pte_t pte,pgprot_t newprot)756 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
757 {
758 /*
759 * Normal and Normal-Tagged are two different memory types and indices
760 * in MAIR_EL1. The mask below has to include PTE_ATTRINDX_MASK.
761 */
762 const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
763 PTE_PROT_NONE | PTE_VALID | PTE_WRITE | PTE_GP |
764 PTE_ATTRINDX_MASK;
765 /* preserve the hardware dirty information */
766 if (pte_hw_dirty(pte))
767 pte = pte_mkdirty(pte);
768 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
769 return pte;
770 }
771
pmd_modify(pmd_t pmd,pgprot_t newprot)772 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
773 {
774 return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
775 }
776
777 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
778 extern int ptep_set_access_flags(struct vm_area_struct *vma,
779 unsigned long address, pte_t *ptep,
780 pte_t entry, int dirty);
781
782 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
783 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
pmdp_set_access_flags(struct vm_area_struct * vma,unsigned long address,pmd_t * pmdp,pmd_t entry,int dirty)784 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
785 unsigned long address, pmd_t *pmdp,
786 pmd_t entry, int dirty)
787 {
788 return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
789 }
790
pud_devmap(pud_t pud)791 static inline int pud_devmap(pud_t pud)
792 {
793 return 0;
794 }
795
pgd_devmap(pgd_t pgd)796 static inline int pgd_devmap(pgd_t pgd)
797 {
798 return 0;
799 }
800 #endif
801
802 /*
803 * Atomic pte/pmd modifications.
804 */
805 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
__ptep_test_and_clear_young(pte_t * ptep)806 static inline int __ptep_test_and_clear_young(pte_t *ptep)
807 {
808 pte_t old_pte, pte;
809
810 pte = READ_ONCE(*ptep);
811 do {
812 old_pte = pte;
813 pte = pte_mkold(pte);
814 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
815 pte_val(old_pte), pte_val(pte));
816 } while (pte_val(pte) != pte_val(old_pte));
817
818 return pte_young(pte);
819 }
820
ptep_test_and_clear_young(struct vm_area_struct * vma,unsigned long address,pte_t * ptep)821 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
822 unsigned long address,
823 pte_t *ptep)
824 {
825 return __ptep_test_and_clear_young(ptep);
826 }
827
828 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
ptep_clear_flush_young(struct vm_area_struct * vma,unsigned long address,pte_t * ptep)829 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
830 unsigned long address, pte_t *ptep)
831 {
832 int young = ptep_test_and_clear_young(vma, address, ptep);
833
834 if (young) {
835 /*
836 * We can elide the trailing DSB here since the worst that can
837 * happen is that a CPU continues to use the young entry in its
838 * TLB and we mistakenly reclaim the associated page. The
839 * window for such an event is bounded by the next
840 * context-switch, which provides a DSB to complete the TLB
841 * invalidation.
842 */
843 flush_tlb_page_nosync(vma, address);
844 }
845
846 return young;
847 }
848
849 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
850 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
pmdp_test_and_clear_young(struct vm_area_struct * vma,unsigned long address,pmd_t * pmdp)851 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
852 unsigned long address,
853 pmd_t *pmdp)
854 {
855 return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
856 }
857 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
858
859 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
ptep_get_and_clear(struct mm_struct * mm,unsigned long address,pte_t * ptep)860 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
861 unsigned long address, pte_t *ptep)
862 {
863 return __pte(xchg_relaxed(&pte_val(*ptep), 0));
864 }
865
866 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
867 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
pmdp_huge_get_and_clear(struct mm_struct * mm,unsigned long address,pmd_t * pmdp)868 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
869 unsigned long address, pmd_t *pmdp)
870 {
871 return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
872 }
873 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
874
875 /*
876 * ptep_set_wrprotect - mark read-only while trasferring potential hardware
877 * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
878 */
879 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
ptep_set_wrprotect(struct mm_struct * mm,unsigned long address,pte_t * ptep)880 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
881 {
882 pte_t old_pte, pte;
883
884 pte = READ_ONCE(*ptep);
885 do {
886 old_pte = pte;
887 pte = pte_wrprotect(pte);
888 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
889 pte_val(old_pte), pte_val(pte));
890 } while (pte_val(pte) != pte_val(old_pte));
891 }
892
893 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
894 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
pmdp_set_wrprotect(struct mm_struct * mm,unsigned long address,pmd_t * pmdp)895 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
896 unsigned long address, pmd_t *pmdp)
897 {
898 ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
899 }
900
901 #define pmdp_establish pmdp_establish
pmdp_establish(struct vm_area_struct * vma,unsigned long address,pmd_t * pmdp,pmd_t pmd)902 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
903 unsigned long address, pmd_t *pmdp, pmd_t pmd)
904 {
905 return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
906 }
907 #endif
908
909 /*
910 * Encode and decode a swap entry:
911 * bits 0-1: present (must be zero)
912 * bits 2-7: swap type
913 * bits 8-57: swap offset
914 * bit 58: PTE_PROT_NONE (must be zero)
915 */
916 #define __SWP_TYPE_SHIFT 2
917 #define __SWP_TYPE_BITS 6
918 #define __SWP_OFFSET_BITS 50
919 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
920 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
921 #define __SWP_OFFSET_MASK ((1UL << __SWP_OFFSET_BITS) - 1)
922
923 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
924 #define __swp_offset(x) (((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
925 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
926
927 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
928 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
929
930 #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
931 #define __pmd_to_swp_entry(pmd) ((swp_entry_t) { pmd_val(pmd) })
932 #define __swp_entry_to_pmd(swp) __pmd((swp).val)
933 #endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */
934
935 /*
936 * Ensure that there are not more swap files than can be encoded in the kernel
937 * PTEs.
938 */
939 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
940
941 extern int kern_addr_valid(unsigned long addr);
942
943 #ifdef CONFIG_ARM64_MTE
944
945 #define __HAVE_ARCH_PREPARE_TO_SWAP
arch_prepare_to_swap(struct page * page)946 static inline int arch_prepare_to_swap(struct page *page)
947 {
948 if (system_supports_mte())
949 return mte_save_tags(page);
950 return 0;
951 }
952
953 #define __HAVE_ARCH_SWAP_INVALIDATE
arch_swap_invalidate_page(int type,pgoff_t offset)954 static inline void arch_swap_invalidate_page(int type, pgoff_t offset)
955 {
956 if (system_supports_mte())
957 mte_invalidate_tags(type, offset);
958 }
959
arch_swap_invalidate_area(int type)960 static inline void arch_swap_invalidate_area(int type)
961 {
962 if (system_supports_mte())
963 mte_invalidate_tags_area(type);
964 }
965
966 #define __HAVE_ARCH_SWAP_RESTORE
arch_swap_restore(swp_entry_t entry,struct page * page)967 static inline void arch_swap_restore(swp_entry_t entry, struct page *page)
968 {
969 if (system_supports_mte() && mte_restore_tags(entry, page))
970 set_bit(PG_mte_tagged, &page->flags);
971 }
972
973 #endif /* CONFIG_ARM64_MTE */
974
975 /*
976 * On AArch64, the cache coherency is handled via the set_pte_at() function.
977 */
update_mmu_cache(struct vm_area_struct * vma,unsigned long addr,pte_t * ptep)978 static inline void update_mmu_cache(struct vm_area_struct *vma,
979 unsigned long addr, pte_t *ptep)
980 {
981 /*
982 * We don't do anything here, so there's a very small chance of
983 * us retaking a user fault which we just fixed up. The alternative
984 * is doing a dsb(ishst), but that penalises the fastpath.
985 */
986 }
987
988 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
989
990 #ifdef CONFIG_ARM64_PA_BITS_52
991 #define phys_to_ttbr(addr) (((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
992 #else
993 #define phys_to_ttbr(addr) (addr)
994 #endif
995
996 /*
997 * On arm64 without hardware Access Flag, copying from user will fail because
998 * the pte is old and cannot be marked young. So we always end up with zeroed
999 * page after fork() + CoW for pfn mappings. We don't always have a
1000 * hardware-managed access flag on arm64.
1001 */
arch_faults_on_old_pte(void)1002 static inline bool arch_faults_on_old_pte(void)
1003 {
1004 WARN_ON(preemptible());
1005
1006 return !cpu_has_hw_af();
1007 }
1008 #define arch_faults_on_old_pte arch_faults_on_old_pte
1009
1010 /*
1011 * Experimentally, it's cheap to set the access flag in hardware and we
1012 * benefit from prefaulting mappings as 'old' to start with.
1013 */
arch_wants_old_prefaulted_pte(void)1014 static inline bool arch_wants_old_prefaulted_pte(void)
1015 {
1016 return !arch_faults_on_old_pte();
1017 }
1018 #define arch_wants_old_prefaulted_pte arch_wants_old_prefaulted_pte
1019
arch_filter_pgprot(pgprot_t prot)1020 static inline pgprot_t arch_filter_pgprot(pgprot_t prot)
1021 {
1022 if (cpus_have_const_cap(ARM64_HAS_EPAN))
1023 return prot;
1024
1025 if (pgprot_val(prot) != pgprot_val(PAGE_EXECONLY))
1026 return prot;
1027
1028 return PAGE_READONLY_EXEC;
1029 }
1030
pud_sect_supported(void)1031 static inline bool pud_sect_supported(void)
1032 {
1033 return PAGE_SIZE == SZ_4K;
1034 }
1035
1036
1037 #endif /* !__ASSEMBLY__ */
1038
1039 #endif /* __ASM_PGTABLE_H */
1040