| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * mm/pgtable-generic.c |
| * |
| * Generic pgtable methods declared in asm-generic/pgtable.h |
| * |
| * Copyright (C) 2010 Linus Torvalds |
| */ |
| |
| #include <linux/pagemap.h> |
| #include <linux/hugetlb.h> |
| #include <asm/tlb.h> |
| #include <asm-generic/pgtable.h> |
| |
| /* |
| * If a p?d_bad entry is found while walking page tables, report |
| * the error, before resetting entry to p?d_none. Usually (but |
| * very seldom) called out from the p?d_none_or_clear_bad macros. |
| */ |
| |
| void pgd_clear_bad(pgd_t *pgd) |
| { |
| pgd_ERROR(*pgd); |
| pgd_clear(pgd); |
| } |
| |
| #ifndef __PAGETABLE_P4D_FOLDED |
| void p4d_clear_bad(p4d_t *p4d) |
| { |
| p4d_ERROR(*p4d); |
| p4d_clear(p4d); |
| } |
| #endif |
| |
| #ifndef __PAGETABLE_PUD_FOLDED |
| void pud_clear_bad(pud_t *pud) |
| { |
| pud_ERROR(*pud); |
| pud_clear(pud); |
| } |
| #endif |
| |
| /* |
| * Note that the pmd variant below can't be stub'ed out just as for p4d/pud |
| * above. pmd folding is special and typically pmd_* macros refer to upper |
| * level even when folded |
| */ |
| void pmd_clear_bad(pmd_t *pmd) |
| { |
| pmd_ERROR(*pmd); |
| pmd_clear(pmd); |
| } |
| |
| #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS |
| /* |
| * Only sets the access flags (dirty, accessed), as well as write |
| * permission. Furthermore, we know it always gets set to a "more |
| * permissive" setting, which allows most architectures to optimize |
| * this. We return whether the PTE actually changed, which in turn |
| * instructs the caller to do things like update__mmu_cache. This |
| * used to be done in the caller, but sparc needs minor faults to |
| * force that call on sun4c so we changed this macro slightly |
| */ |
| int ptep_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pte_t *ptep, |
| pte_t entry, int dirty) |
| { |
| int changed = !pte_same(*ptep, entry); |
| if (changed) { |
| set_pte_at(vma->vm_mm, address, ptep, entry); |
| flush_tlb_fix_spurious_fault(vma, address); |
| } |
| return changed; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH |
| int ptep_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pte_t *ptep) |
| { |
| int young; |
| young = ptep_test_and_clear_young(vma, address, ptep); |
| if (young) |
| flush_tlb_page(vma, address); |
| return young; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH |
| pte_t ptep_clear_flush(struct vm_area_struct *vma, unsigned long address, |
| pte_t *ptep) |
| { |
| struct mm_struct *mm = (vma)->vm_mm; |
| pte_t pte; |
| pte = ptep_get_and_clear(mm, address, ptep); |
| if (pte_accessible(mm, pte)) |
| flush_tlb_page(vma, address); |
| return pte; |
| } |
| #endif |
| |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| |
| #ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS |
| int pmdp_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp, |
| pmd_t entry, int dirty) |
| { |
| int changed = !pmd_same(*pmdp, entry); |
| VM_BUG_ON(address & ~HPAGE_PMD_MASK); |
| if (changed) { |
| set_pmd_at(vma->vm_mm, address, pmdp, entry); |
| flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); |
| } |
| return changed; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH |
| int pmdp_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp) |
| { |
| int young; |
| VM_BUG_ON(address & ~HPAGE_PMD_MASK); |
| young = pmdp_test_and_clear_young(vma, address, pmdp); |
| if (young) |
| flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); |
| return young; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH |
| pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, |
| pmd_t *pmdp) |
| { |
| pmd_t pmd; |
| VM_BUG_ON(address & ~HPAGE_PMD_MASK); |
| VM_BUG_ON((pmd_present(*pmdp) && !pmd_trans_huge(*pmdp) && |
| !pmd_devmap(*pmdp)) || !pmd_present(*pmdp)); |
| pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp); |
| flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); |
| return pmd; |
| } |
| |
| #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD |
| pud_t pudp_huge_clear_flush(struct vm_area_struct *vma, unsigned long address, |
| pud_t *pudp) |
| { |
| pud_t pud; |
| |
| VM_BUG_ON(address & ~HPAGE_PUD_MASK); |
| VM_BUG_ON(!pud_trans_huge(*pudp) && !pud_devmap(*pudp)); |
| pud = pudp_huge_get_and_clear(vma->vm_mm, address, pudp); |
| flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE); |
| return pud; |
| } |
| #endif |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT |
| void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, |
| pgtable_t pgtable) |
| { |
| assert_spin_locked(pmd_lockptr(mm, pmdp)); |
| |
| /* FIFO */ |
| if (!pmd_huge_pte(mm, pmdp)) |
| INIT_LIST_HEAD(&pgtable->lru); |
| else |
| list_add(&pgtable->lru, &pmd_huge_pte(mm, pmdp)->lru); |
| pmd_huge_pte(mm, pmdp) = pgtable; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW |
| /* no "address" argument so destroys page coloring of some arch */ |
| pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) |
| { |
| pgtable_t pgtable; |
| |
| assert_spin_locked(pmd_lockptr(mm, pmdp)); |
| |
| /* FIFO */ |
| pgtable = pmd_huge_pte(mm, pmdp); |
| pmd_huge_pte(mm, pmdp) = list_first_entry_or_null(&pgtable->lru, |
| struct page, lru); |
| if (pmd_huge_pte(mm, pmdp)) |
| list_del(&pgtable->lru); |
| return pgtable; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_INVALIDATE |
| pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, |
| pmd_t *pmdp) |
| { |
| pmd_t old = pmdp_establish(vma, address, pmdp, pmd_mkinvalid(*pmdp)); |
| flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); |
| return old; |
| } |
| #endif |
| |
| #ifndef pmdp_collapse_flush |
| pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long address, |
| pmd_t *pmdp) |
| { |
| /* |
| * pmd and hugepage pte format are same. So we could |
| * use the same function. |
| */ |
| pmd_t pmd; |
| |
| VM_BUG_ON(address & ~HPAGE_PMD_MASK); |
| VM_BUG_ON(pmd_trans_huge(*pmdp)); |
| pmd = pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp); |
| |
| /* collapse entails shooting down ptes not pmd */ |
| flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); |
| return pmd; |
| } |
| #endif |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |