1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2012 ARM Ltd.
5 #ifndef __ASM_PGTABLE_H
6 #define __ASM_PGTABLE_H
9 #include <asm/proc-fns.h>
11 #include <asm/memory.h>
12 #include <asm/pgtable-hwdef.h>
13 #include <asm/pgtable-prot.h>
14 #include <asm/tlbflush.h>
19 * VMALLOC_START: beginning of the kernel vmalloc space
20 * VMALLOC_END: extends to the available space below vmemmap, PCI I/O space
23 #define VMALLOC_START (MODULES_END)
24 #define VMALLOC_END (- PUD_SIZE - VMEMMAP_SIZE - SZ_64K)
26 #define FIRST_USER_ADDRESS 0UL
30 #include <asm/cmpxchg.h>
31 #include <asm/fixmap.h>
32 #include <linux/mmdebug.h>
33 #include <linux/mm_types.h>
34 #include <linux/sched.h>
36 extern struct page *vmemmap;
38 extern void __pte_error(const char *file, int line, unsigned long val);
39 extern void __pmd_error(const char *file, int line, unsigned long val);
40 extern void __pud_error(const char *file, int line, unsigned long val);
41 extern void __pgd_error(const char *file, int line, unsigned long val);
44 * ZERO_PAGE is a global shared page that is always zero: used
45 * for zero-mapped memory areas etc..
47 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
48 #define ZERO_PAGE(vaddr) phys_to_page(__pa_symbol(empty_zero_page))
50 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte))
53 * Macros to convert between a physical address and its placement in a
54 * page table entry, taking care of 52-bit addresses.
56 #ifdef CONFIG_ARM64_PA_BITS_52
57 #define __pte_to_phys(pte) \
58 ((pte_val(pte) & PTE_ADDR_LOW) | ((pte_val(pte) & PTE_ADDR_HIGH) << 36))
59 #define __phys_to_pte_val(phys) (((phys) | ((phys) >> 36)) & PTE_ADDR_MASK)
61 #define __pte_to_phys(pte) (pte_val(pte) & PTE_ADDR_MASK)
62 #define __phys_to_pte_val(phys) (phys)
65 #define pte_pfn(pte) (__pte_to_phys(pte) >> PAGE_SHIFT)
66 #define pfn_pte(pfn,prot) \
67 __pte(__phys_to_pte_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
69 #define pte_none(pte) (!pte_val(pte))
70 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0))
71 #define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
74 * The following only work if pte_present(). Undefined behaviour otherwise.
76 #define pte_present(pte) (!!(pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)))
77 #define pte_young(pte) (!!(pte_val(pte) & PTE_AF))
78 #define pte_special(pte) (!!(pte_val(pte) & PTE_SPECIAL))
79 #define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE))
80 #define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN))
81 #define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT))
82 #define pte_devmap(pte) (!!(pte_val(pte) & PTE_DEVMAP))
84 #define pte_cont_addr_end(addr, end) \
85 ({ unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK; \
86 (__boundary - 1 < (end) - 1) ? __boundary : (end); \
89 #define pmd_cont_addr_end(addr, end) \
90 ({ unsigned long __boundary = ((addr) + CONT_PMD_SIZE) & CONT_PMD_MASK; \
91 (__boundary - 1 < (end) - 1) ? __boundary : (end); \
94 #define pte_hw_dirty(pte) (pte_write(pte) && !(pte_val(pte) & PTE_RDONLY))
95 #define pte_sw_dirty(pte) (!!(pte_val(pte) & PTE_DIRTY))
96 #define pte_dirty(pte) (pte_sw_dirty(pte) || pte_hw_dirty(pte))
98 #define pte_valid(pte) (!!(pte_val(pte) & PTE_VALID))
100 * Execute-only user mappings do not have the PTE_USER bit set. All valid
101 * kernel mappings have the PTE_UXN bit set.
103 #define pte_valid_not_user(pte) \
104 ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == (PTE_VALID | PTE_UXN))
105 #define pte_valid_young(pte) \
106 ((pte_val(pte) & (PTE_VALID | PTE_AF)) == (PTE_VALID | PTE_AF))
107 #define pte_valid_user(pte) \
108 ((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER))
111 * Could the pte be present in the TLB? We must check mm_tlb_flush_pending
112 * so that we don't erroneously return false for pages that have been
113 * remapped as PROT_NONE but are yet to be flushed from the TLB.
115 #define pte_accessible(mm, pte) \
116 (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid_young(pte))
119 * p??_access_permitted() is true for valid user mappings (subject to the
120 * write permission check) other than user execute-only which do not have the
121 * PTE_USER bit set. PROT_NONE mappings do not have the PTE_VALID bit set.
123 #define pte_access_permitted(pte, write) \
124 (pte_valid_user(pte) && (!(write) || pte_write(pte)))
125 #define pmd_access_permitted(pmd, write) \
126 (pte_access_permitted(pmd_pte(pmd), (write)))
127 #define pud_access_permitted(pud, write) \
128 (pte_access_permitted(pud_pte(pud), (write)))
130 static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot)
132 pte_val(pte) &= ~pgprot_val(prot);
136 static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot)
138 pte_val(pte) |= pgprot_val(prot);
142 static inline pte_t pte_wrprotect(pte_t pte)
144 pte = clear_pte_bit(pte, __pgprot(PTE_WRITE));
145 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
149 static inline pte_t pte_mkwrite(pte_t pte)
151 pte = set_pte_bit(pte, __pgprot(PTE_WRITE));
152 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
156 static inline pte_t pte_mkclean(pte_t pte)
158 pte = clear_pte_bit(pte, __pgprot(PTE_DIRTY));
159 pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
164 static inline pte_t pte_mkdirty(pte_t pte)
166 pte = set_pte_bit(pte, __pgprot(PTE_DIRTY));
169 pte = clear_pte_bit(pte, __pgprot(PTE_RDONLY));
174 static inline pte_t pte_mkold(pte_t pte)
176 return clear_pte_bit(pte, __pgprot(PTE_AF));
179 static inline pte_t pte_mkyoung(pte_t pte)
181 return set_pte_bit(pte, __pgprot(PTE_AF));
184 static inline pte_t pte_mkspecial(pte_t pte)
186 return set_pte_bit(pte, __pgprot(PTE_SPECIAL));
189 static inline pte_t pte_mkcont(pte_t pte)
191 pte = set_pte_bit(pte, __pgprot(PTE_CONT));
192 return set_pte_bit(pte, __pgprot(PTE_TYPE_PAGE));
195 static inline pte_t pte_mknoncont(pte_t pte)
197 return clear_pte_bit(pte, __pgprot(PTE_CONT));
200 static inline pte_t pte_mkpresent(pte_t pte)
202 return set_pte_bit(pte, __pgprot(PTE_VALID));
205 static inline pmd_t pmd_mkcont(pmd_t pmd)
207 return __pmd(pmd_val(pmd) | PMD_SECT_CONT);
210 static inline pte_t pte_mkdevmap(pte_t pte)
212 return set_pte_bit(pte, __pgprot(PTE_DEVMAP | PTE_SPECIAL));
215 static inline void set_pte(pte_t *ptep, pte_t pte)
217 WRITE_ONCE(*ptep, pte);
220 * Only if the new pte is valid and kernel, otherwise TLB maintenance
221 * or update_mmu_cache() have the necessary barriers.
223 if (pte_valid_not_user(pte)) {
229 extern void __sync_icache_dcache(pte_t pteval);
232 * PTE bits configuration in the presence of hardware Dirty Bit Management
233 * (PTE_WRITE == PTE_DBM):
235 * Dirty Writable | PTE_RDONLY PTE_WRITE PTE_DIRTY (sw)
241 * When hardware DBM is not present, the sofware PTE_DIRTY bit is updated via
242 * the page fault mechanism. Checking the dirty status of a pte becomes:
244 * PTE_DIRTY || (PTE_WRITE && !PTE_RDONLY)
247 static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep,
252 if (!IS_ENABLED(CONFIG_DEBUG_VM))
255 old_pte = READ_ONCE(*ptep);
257 if (!pte_valid(old_pte) || !pte_valid(pte))
259 if (mm != current->active_mm && atomic_read(&mm->mm_users) <= 1)
263 * Check for potential race with hardware updates of the pte
264 * (ptep_set_access_flags safely changes valid ptes without going
265 * through an invalid entry).
267 VM_WARN_ONCE(!pte_young(pte),
268 "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
269 __func__, pte_val(old_pte), pte_val(pte));
270 VM_WARN_ONCE(pte_write(old_pte) && !pte_dirty(pte),
271 "%s: racy dirty state clearing: 0x%016llx -> 0x%016llx",
272 __func__, pte_val(old_pte), pte_val(pte));
275 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
276 pte_t *ptep, pte_t pte)
278 if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
279 __sync_icache_dcache(pte);
281 __check_racy_pte_update(mm, ptep, pte);
287 * Huge pte definitions.
289 #define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT))
292 * Hugetlb definitions.
294 #define HUGE_MAX_HSTATE 4
295 #define HPAGE_SHIFT PMD_SHIFT
296 #define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT)
297 #define HPAGE_MASK (~(HPAGE_SIZE - 1))
298 #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
300 static inline pte_t pgd_pte(pgd_t pgd)
302 return __pte(pgd_val(pgd));
305 static inline pte_t pud_pte(pud_t pud)
307 return __pte(pud_val(pud));
310 static inline pud_t pte_pud(pte_t pte)
312 return __pud(pte_val(pte));
315 static inline pmd_t pud_pmd(pud_t pud)
317 return __pmd(pud_val(pud));
320 static inline pte_t pmd_pte(pmd_t pmd)
322 return __pte(pmd_val(pmd));
325 static inline pmd_t pte_pmd(pte_t pte)
327 return __pmd(pte_val(pte));
330 static inline pgprot_t mk_pud_sect_prot(pgprot_t prot)
332 return __pgprot((pgprot_val(prot) & ~PUD_TABLE_BIT) | PUD_TYPE_SECT);
335 static inline pgprot_t mk_pmd_sect_prot(pgprot_t prot)
337 return __pgprot((pgprot_val(prot) & ~PMD_TABLE_BIT) | PMD_TYPE_SECT);
340 #ifdef CONFIG_NUMA_BALANCING
342 * See the comment in include/asm-generic/pgtable.h
344 static inline int pte_protnone(pte_t pte)
346 return (pte_val(pte) & (PTE_VALID | PTE_PROT_NONE)) == PTE_PROT_NONE;
349 static inline int pmd_protnone(pmd_t pmd)
351 return pte_protnone(pmd_pte(pmd));
359 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
360 #define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT))
361 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
363 #define pmd_present(pmd) pte_present(pmd_pte(pmd))
364 #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd))
365 #define pmd_young(pmd) pte_young(pmd_pte(pmd))
366 #define pmd_valid(pmd) pte_valid(pmd_pte(pmd))
367 #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd)))
368 #define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd)))
369 #define pmd_mkwrite(pmd) pte_pmd(pte_mkwrite(pmd_pte(pmd)))
370 #define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd)))
371 #define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd)))
372 #define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd)))
373 #define pmd_mknotpresent(pmd) (__pmd(pmd_val(pmd) & ~PMD_SECT_VALID))
375 #define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd))
377 #define pmd_write(pmd) pte_write(pmd_pte(pmd))
379 #define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
381 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
382 #define pmd_devmap(pmd) pte_devmap(pmd_pte(pmd))
384 static inline pmd_t pmd_mkdevmap(pmd_t pmd)
386 return pte_pmd(set_pte_bit(pmd_pte(pmd), __pgprot(PTE_DEVMAP)));
389 #define __pmd_to_phys(pmd) __pte_to_phys(pmd_pte(pmd))
390 #define __phys_to_pmd_val(phys) __phys_to_pte_val(phys)
391 #define pmd_pfn(pmd) ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT)
392 #define pfn_pmd(pfn,prot) __pmd(__phys_to_pmd_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
393 #define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot)
395 #define pud_young(pud) pte_young(pud_pte(pud))
396 #define pud_mkyoung(pud) pte_pud(pte_mkyoung(pud_pte(pud)))
397 #define pud_write(pud) pte_write(pud_pte(pud))
399 #define pud_mkhuge(pud) (__pud(pud_val(pud) & ~PUD_TABLE_BIT))
401 #define __pud_to_phys(pud) __pte_to_phys(pud_pte(pud))
402 #define __phys_to_pud_val(phys) __phys_to_pte_val(phys)
403 #define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
404 #define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
406 #define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
408 #define __pgd_to_phys(pgd) __pte_to_phys(pgd_pte(pgd))
409 #define __phys_to_pgd_val(phys) __phys_to_pte_val(phys)
411 #define __pgprot_modify(prot,mask,bits) \
412 __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
415 * Mark the prot value as uncacheable and unbufferable.
417 #define pgprot_noncached(prot) \
418 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE) | PTE_PXN | PTE_UXN)
419 #define pgprot_writecombine(prot) \
420 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
421 #define pgprot_device(prot) \
422 __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_PXN | PTE_UXN)
424 * DMA allocations for non-coherent devices use what the Arm architecture calls
425 * "Normal non-cacheable" memory, which permits speculation, unaligned accesses
426 * and merging of writes. This is different from "Device-nGnR[nE]" memory which
427 * is intended for MMIO and thus forbids speculation, preserves access size,
428 * requires strict alignment and can also force write responses to come from the
431 #define pgprot_dmacoherent(prot) \
432 __pgprot_modify(prot, PTE_ATTRINDX_MASK, \
433 PTE_ATTRINDX(MT_NORMAL_NC) | PTE_PXN | PTE_UXN)
435 #define __HAVE_PHYS_MEM_ACCESS_PROT
437 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
438 unsigned long size, pgprot_t vma_prot);
440 #define pmd_none(pmd) (!pmd_val(pmd))
442 #define pmd_bad(pmd) (!(pmd_val(pmd) & PMD_TABLE_BIT))
444 #define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
446 #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
449 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
450 static inline bool pud_sect(pud_t pud) { return false; }
451 static inline bool pud_table(pud_t pud) { return true; }
453 #define pud_sect(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \
455 #define pud_table(pud) ((pud_val(pud) & PUD_TYPE_MASK) == \
459 extern pgd_t init_pg_dir[PTRS_PER_PGD];
460 extern pgd_t init_pg_end[];
461 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
462 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
463 extern pgd_t tramp_pg_dir[PTRS_PER_PGD];
465 extern void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd);
467 static inline bool in_swapper_pgdir(void *addr)
469 return ((unsigned long)addr & PAGE_MASK) ==
470 ((unsigned long)swapper_pg_dir & PAGE_MASK);
473 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
475 #ifdef __PAGETABLE_PMD_FOLDED
476 if (in_swapper_pgdir(pmdp)) {
477 set_swapper_pgd((pgd_t *)pmdp, __pgd(pmd_val(pmd)));
480 #endif /* __PAGETABLE_PMD_FOLDED */
482 WRITE_ONCE(*pmdp, pmd);
484 if (pmd_valid(pmd)) {
490 static inline void pmd_clear(pmd_t *pmdp)
492 set_pmd(pmdp, __pmd(0));
495 static inline phys_addr_t pmd_page_paddr(pmd_t pmd)
497 return __pmd_to_phys(pmd);
500 static inline void pte_unmap(pte_t *pte) { }
502 /* Find an entry in the third-level page table. */
503 #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
505 #define pte_offset_phys(dir,addr) (pmd_page_paddr(READ_ONCE(*(dir))) + pte_index(addr) * sizeof(pte_t))
506 #define pte_offset_kernel(dir,addr) ((pte_t *)__va(pte_offset_phys((dir), (addr))))
508 #define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr))
510 #define pte_set_fixmap(addr) ((pte_t *)set_fixmap_offset(FIX_PTE, addr))
511 #define pte_set_fixmap_offset(pmd, addr) pte_set_fixmap(pte_offset_phys(pmd, addr))
512 #define pte_clear_fixmap() clear_fixmap(FIX_PTE)
514 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(__pmd_to_phys(pmd)))
516 /* use ONLY for statically allocated translation tables */
517 #define pte_offset_kimg(dir,addr) ((pte_t *)__phys_to_kimg(pte_offset_phys((dir), (addr))))
520 * Conversion functions: convert a page and protection to a page entry,
521 * and a page entry and page directory to the page they refer to.
523 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page),prot)
525 #if CONFIG_PGTABLE_LEVELS > 2
527 #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
529 #define pud_none(pud) (!pud_val(pud))
530 #define pud_bad(pud) (!(pud_val(pud) & PUD_TABLE_BIT))
531 #define pud_present(pud) pte_present(pud_pte(pud))
532 #define pud_valid(pud) pte_valid(pud_pte(pud))
534 static inline void set_pud(pud_t *pudp, pud_t pud)
536 #ifdef __PAGETABLE_PUD_FOLDED
537 if (in_swapper_pgdir(pudp)) {
538 set_swapper_pgd((pgd_t *)pudp, __pgd(pud_val(pud)));
541 #endif /* __PAGETABLE_PUD_FOLDED */
543 WRITE_ONCE(*pudp, pud);
545 if (pud_valid(pud)) {
551 static inline void pud_clear(pud_t *pudp)
553 set_pud(pudp, __pud(0));
556 static inline phys_addr_t pud_page_paddr(pud_t pud)
558 return __pud_to_phys(pud);
561 /* Find an entry in the second-level page table. */
562 #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
564 #define pmd_offset_phys(dir, addr) (pud_page_paddr(READ_ONCE(*(dir))) + pmd_index(addr) * sizeof(pmd_t))
565 #define pmd_offset(dir, addr) ((pmd_t *)__va(pmd_offset_phys((dir), (addr))))
567 #define pmd_set_fixmap(addr) ((pmd_t *)set_fixmap_offset(FIX_PMD, addr))
568 #define pmd_set_fixmap_offset(pud, addr) pmd_set_fixmap(pmd_offset_phys(pud, addr))
569 #define pmd_clear_fixmap() clear_fixmap(FIX_PMD)
571 #define pud_page(pud) pfn_to_page(__phys_to_pfn(__pud_to_phys(pud)))
573 /* use ONLY for statically allocated translation tables */
574 #define pmd_offset_kimg(dir,addr) ((pmd_t *)__phys_to_kimg(pmd_offset_phys((dir), (addr))))
578 #define pud_page_paddr(pud) ({ BUILD_BUG(); 0; })
580 /* Match pmd_offset folding in <asm/generic/pgtable-nopmd.h> */
581 #define pmd_set_fixmap(addr) NULL
582 #define pmd_set_fixmap_offset(pudp, addr) ((pmd_t *)pudp)
583 #define pmd_clear_fixmap()
585 #define pmd_offset_kimg(dir,addr) ((pmd_t *)dir)
587 #endif /* CONFIG_PGTABLE_LEVELS > 2 */
589 #if CONFIG_PGTABLE_LEVELS > 3
591 #define pud_ERROR(pud) __pud_error(__FILE__, __LINE__, pud_val(pud))
593 #define pgd_none(pgd) (!pgd_val(pgd))
594 #define pgd_bad(pgd) (!(pgd_val(pgd) & 2))
595 #define pgd_present(pgd) (pgd_val(pgd))
597 static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
599 if (in_swapper_pgdir(pgdp)) {
600 set_swapper_pgd(pgdp, pgd);
604 WRITE_ONCE(*pgdp, pgd);
609 static inline void pgd_clear(pgd_t *pgdp)
611 set_pgd(pgdp, __pgd(0));
614 static inline phys_addr_t pgd_page_paddr(pgd_t pgd)
616 return __pgd_to_phys(pgd);
619 /* Find an entry in the frst-level page table. */
620 #define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
622 #define pud_offset_phys(dir, addr) (pgd_page_paddr(READ_ONCE(*(dir))) + pud_index(addr) * sizeof(pud_t))
623 #define pud_offset(dir, addr) ((pud_t *)__va(pud_offset_phys((dir), (addr))))
625 #define pud_set_fixmap(addr) ((pud_t *)set_fixmap_offset(FIX_PUD, addr))
626 #define pud_set_fixmap_offset(pgd, addr) pud_set_fixmap(pud_offset_phys(pgd, addr))
627 #define pud_clear_fixmap() clear_fixmap(FIX_PUD)
629 #define pgd_page(pgd) pfn_to_page(__phys_to_pfn(__pgd_to_phys(pgd)))
631 /* use ONLY for statically allocated translation tables */
632 #define pud_offset_kimg(dir,addr) ((pud_t *)__phys_to_kimg(pud_offset_phys((dir), (addr))))
636 #define pgd_page_paddr(pgd) ({ BUILD_BUG(); 0;})
638 /* Match pud_offset folding in <asm/generic/pgtable-nopud.h> */
639 #define pud_set_fixmap(addr) NULL
640 #define pud_set_fixmap_offset(pgdp, addr) ((pud_t *)pgdp)
641 #define pud_clear_fixmap()
643 #define pud_offset_kimg(dir,addr) ((pud_t *)dir)
645 #endif /* CONFIG_PGTABLE_LEVELS > 3 */
647 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
649 /* to find an entry in a page-table-directory */
650 #define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
652 #define pgd_offset_raw(pgd, addr) ((pgd) + pgd_index(addr))
654 #define pgd_offset(mm, addr) (pgd_offset_raw((mm)->pgd, (addr)))
656 /* to find an entry in a kernel page-table-directory */
657 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
659 #define pgd_set_fixmap(addr) ((pgd_t *)set_fixmap_offset(FIX_PGD, addr))
660 #define pgd_clear_fixmap() clear_fixmap(FIX_PGD)
662 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
664 const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
665 PTE_PROT_NONE | PTE_VALID | PTE_WRITE;
666 /* preserve the hardware dirty information */
667 if (pte_hw_dirty(pte))
668 pte = pte_mkdirty(pte);
669 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
673 static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
675 return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
678 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
679 extern int ptep_set_access_flags(struct vm_area_struct *vma,
680 unsigned long address, pte_t *ptep,
681 pte_t entry, int dirty);
683 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
684 #define __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
685 static inline int pmdp_set_access_flags(struct vm_area_struct *vma,
686 unsigned long address, pmd_t *pmdp,
687 pmd_t entry, int dirty)
689 return ptep_set_access_flags(vma, address, (pte_t *)pmdp, pmd_pte(entry), dirty);
692 static inline int pud_devmap(pud_t pud)
697 static inline int pgd_devmap(pgd_t pgd)
704 * Atomic pte/pmd modifications.
706 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
707 static inline int __ptep_test_and_clear_young(pte_t *ptep)
711 pte = READ_ONCE(*ptep);
714 pte = pte_mkold(pte);
715 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
716 pte_val(old_pte), pte_val(pte));
717 } while (pte_val(pte) != pte_val(old_pte));
719 return pte_young(pte);
722 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
723 unsigned long address,
726 return __ptep_test_and_clear_young(ptep);
729 #define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
730 static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
731 unsigned long address, pte_t *ptep)
733 int young = ptep_test_and_clear_young(vma, address, ptep);
737 * We can elide the trailing DSB here since the worst that can
738 * happen is that a CPU continues to use the young entry in its
739 * TLB and we mistakenly reclaim the associated page. The
740 * window for such an event is bounded by the next
741 * context-switch, which provides a DSB to complete the TLB
744 flush_tlb_page_nosync(vma, address);
750 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
751 #define __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
752 static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
753 unsigned long address,
756 return ptep_test_and_clear_young(vma, address, (pte_t *)pmdp);
758 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
760 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
761 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
762 unsigned long address, pte_t *ptep)
764 return __pte(xchg_relaxed(&pte_val(*ptep), 0));
767 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
768 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
769 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
770 unsigned long address, pmd_t *pmdp)
772 return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
774 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
777 * ptep_set_wrprotect - mark read-only while trasferring potential hardware
778 * dirty status (PTE_DBM && !PTE_RDONLY) to the software PTE_DIRTY bit.
780 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
781 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
785 pte = READ_ONCE(*ptep);
789 * If hardware-dirty (PTE_WRITE/DBM bit set and PTE_RDONLY
790 * clear), set the PTE_DIRTY bit.
792 if (pte_hw_dirty(pte))
793 pte = pte_mkdirty(pte);
794 pte = pte_wrprotect(pte);
795 pte_val(pte) = cmpxchg_relaxed(&pte_val(*ptep),
796 pte_val(old_pte), pte_val(pte));
797 } while (pte_val(pte) != pte_val(old_pte));
800 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
801 #define __HAVE_ARCH_PMDP_SET_WRPROTECT
802 static inline void pmdp_set_wrprotect(struct mm_struct *mm,
803 unsigned long address, pmd_t *pmdp)
805 ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
808 #define pmdp_establish pmdp_establish
809 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
810 unsigned long address, pmd_t *pmdp, pmd_t pmd)
812 return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
817 * Encode and decode a swap entry:
818 * bits 0-1: present (must be zero)
819 * bits 2-7: swap type
820 * bits 8-57: swap offset
821 * bit 58: PTE_PROT_NONE (must be zero)
823 #define __SWP_TYPE_SHIFT 2
824 #define __SWP_TYPE_BITS 6
825 #define __SWP_OFFSET_BITS 50
826 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
827 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
828 #define __SWP_OFFSET_MASK ((1UL << __SWP_OFFSET_BITS) - 1)
830 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
831 #define __swp_offset(x) (((x).val >> __SWP_OFFSET_SHIFT) & __SWP_OFFSET_MASK)
832 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
834 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
835 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
838 * Ensure that there are not more swap files than can be encoded in the kernel
841 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
843 extern int kern_addr_valid(unsigned long addr);
845 #include <asm-generic/pgtable.h>
848 * On AArch64, the cache coherency is handled via the set_pte_at() function.
850 static inline void update_mmu_cache(struct vm_area_struct *vma,
851 unsigned long addr, pte_t *ptep)
854 * We don't do anything here, so there's a very small chance of
855 * us retaking a user fault which we just fixed up. The alternative
856 * is doing a dsb(ishst), but that penalises the fastpath.
860 #define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
862 #ifdef CONFIG_ARM64_PA_BITS_52
863 #define phys_to_ttbr(addr) (((addr) | ((addr) >> 46)) & TTBR_BADDR_MASK_52)
865 #define phys_to_ttbr(addr) (addr)
869 * On arm64 without hardware Access Flag, copying from user will fail because
870 * the pte is old and cannot be marked young. So we always end up with zeroed
871 * page after fork() + CoW for pfn mappings. We don't always have a
872 * hardware-managed access flag on arm64.
874 static inline bool arch_faults_on_old_pte(void)
876 WARN_ON(preemptible());
878 return !cpu_has_hw_af();
880 #define arch_faults_on_old_pte arch_faults_on_old_pte
882 #endif /* !__ASSEMBLY__ */
884 #endif /* __ASM_PGTABLE_H */