| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _LINUX_PGTABLE_H |
| #define _LINUX_PGTABLE_H |
| |
| #include <linux/pfn.h> |
| #include <asm/pgtable.h> |
| |
| #ifndef __ASSEMBLY__ |
| #ifdef CONFIG_MMU |
| |
| #include <linux/mm_types.h> |
| #include <linux/bug.h> |
| #include <linux/errno.h> |
| #include <asm-generic/pgtable_uffd.h> |
| |
| #if 5 - defined(__PAGETABLE_P4D_FOLDED) - defined(__PAGETABLE_PUD_FOLDED) - \ |
| defined(__PAGETABLE_PMD_FOLDED) != CONFIG_PGTABLE_LEVELS |
| #error CONFIG_PGTABLE_LEVELS is not consistent with __PAGETABLE_{P4D,PUD,PMD}_FOLDED |
| #endif |
| |
| /* |
| * On almost all architectures and configurations, 0 can be used as the |
| * upper ceiling to free_pgtables(): on many architectures it has the same |
| * effect as using TASK_SIZE. However, there is one configuration which |
| * must impose a more careful limit, to avoid freeing kernel pgtables. |
| */ |
| #ifndef USER_PGTABLES_CEILING |
| #define USER_PGTABLES_CEILING 0UL |
| #endif |
| |
| /* |
| * A page table page can be thought of an array like this: pXd_t[PTRS_PER_PxD] |
| * |
| * The pXx_index() functions return the index of the entry in the page |
| * table page which would control the given virtual address |
| * |
| * As these functions may be used by the same code for different levels of |
| * the page table folding, they are always available, regardless of |
| * CONFIG_PGTABLE_LEVELS value. For the folded levels they simply return 0 |
| * because in such cases PTRS_PER_PxD equals 1. |
| */ |
| |
| static inline unsigned long pte_index(unsigned long address) |
| { |
| return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1); |
| } |
| |
| #ifndef pmd_index |
| static inline unsigned long pmd_index(unsigned long address) |
| { |
| return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); |
| } |
| #define pmd_index pmd_index |
| #endif |
| |
| #ifndef pud_index |
| static inline unsigned long pud_index(unsigned long address) |
| { |
| return (address >> PUD_SHIFT) & (PTRS_PER_PUD - 1); |
| } |
| #define pud_index pud_index |
| #endif |
| |
| #ifndef pgd_index |
| /* Must be a compile-time constant, so implement it as a macro */ |
| #define pgd_index(a) (((a) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)) |
| #endif |
| |
| #ifndef pte_offset_kernel |
| static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address) |
| { |
| return (pte_t *)pmd_page_vaddr(*pmd) + pte_index(address); |
| } |
| #define pte_offset_kernel pte_offset_kernel |
| #endif |
| |
| #if defined(CONFIG_HIGHPTE) |
| #define pte_offset_map(dir, address) \ |
| ((pte_t *)kmap_atomic(pmd_page(*(dir))) + \ |
| pte_index((address))) |
| #define pte_unmap(pte) kunmap_atomic((pte)) |
| #else |
| #define pte_offset_map(dir, address) pte_offset_kernel((dir), (address)) |
| #define pte_unmap(pte) ((void)(pte)) /* NOP */ |
| #endif |
| |
| /* Find an entry in the second-level page table.. */ |
| #ifndef pmd_offset |
| static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) |
| { |
| return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); |
| } |
| #define pmd_offset pmd_offset |
| #endif |
| |
| #ifndef pud_offset |
| static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address) |
| { |
| return (pud_t *)p4d_page_vaddr(*p4d) + pud_index(address); |
| } |
| #define pud_offset pud_offset |
| #endif |
| |
| static inline pgd_t *pgd_offset_pgd(pgd_t *pgd, unsigned long address) |
| { |
| return (pgd + pgd_index(address)); |
| }; |
| |
| /* |
| * a shortcut to get a pgd_t in a given mm |
| */ |
| #ifndef pgd_offset |
| #define pgd_offset(mm, address) pgd_offset_pgd((mm)->pgd, (address)) |
| #endif |
| |
| /* |
| * a shortcut which implies the use of the kernel's pgd, instead |
| * of a process's |
| */ |
| #ifndef pgd_offset_k |
| #define pgd_offset_k(address) pgd_offset(&init_mm, (address)) |
| #endif |
| |
| /* |
| * In many cases it is known that a virtual address is mapped at PMD or PTE |
| * level, so instead of traversing all the page table levels, we can get a |
| * pointer to the PMD entry in user or kernel page table or translate a virtual |
| * address to the pointer in the PTE in the kernel page tables with simple |
| * helpers. |
| */ |
| static inline pmd_t *pmd_off(struct mm_struct *mm, unsigned long va) |
| { |
| return pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, va), va), va), va); |
| } |
| |
| static inline pmd_t *pmd_off_k(unsigned long va) |
| { |
| return pmd_offset(pud_offset(p4d_offset(pgd_offset_k(va), va), va), va); |
| } |
| |
| static inline pte_t *virt_to_kpte(unsigned long vaddr) |
| { |
| pmd_t *pmd = pmd_off_k(vaddr); |
| |
| return pmd_none(*pmd) ? NULL : pte_offset_kernel(pmd, vaddr); |
| } |
| |
| #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS |
| extern int ptep_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pte_t *ptep, |
| pte_t entry, int dirty); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| extern int pmdp_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp, |
| pmd_t entry, int dirty); |
| extern int pudp_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pud_t *pudp, |
| pud_t entry, int dirty); |
| #else |
| static inline int pmdp_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp, |
| pmd_t entry, int dirty) |
| { |
| BUILD_BUG(); |
| return 0; |
| } |
| static inline int pudp_set_access_flags(struct vm_area_struct *vma, |
| unsigned long address, pud_t *pudp, |
| pud_t entry, int dirty) |
| { |
| BUILD_BUG(); |
| return 0; |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG |
| static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, |
| unsigned long address, |
| pte_t *ptep) |
| { |
| pte_t pte = *ptep; |
| int r = 1; |
| if (!pte_young(pte)) |
| r = 0; |
| else |
| set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte)); |
| return r; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| pmd_t pmd = *pmdp; |
| int r = 1; |
| if (!pmd_young(pmd)) |
| r = 0; |
| else |
| set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd)); |
| return r; |
| } |
| #else |
| static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| BUILD_BUG(); |
| return 0; |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH |
| int ptep_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pte_t *ptep); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| extern int pmdp_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp); |
| #else |
| /* |
| * Despite relevant to THP only, this API is called from generic rmap code |
| * under PageTransHuge(), hence needs a dummy implementation for !THP |
| */ |
| static inline int pmdp_clear_flush_young(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp) |
| { |
| BUILD_BUG(); |
| return 0; |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR |
| static inline pte_t ptep_get_and_clear(struct mm_struct *mm, |
| unsigned long address, |
| pte_t *ptep) |
| { |
| pte_t pte = *ptep; |
| pte_clear(mm, address, ptep); |
| return pte; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_GET |
| static inline pte_t ptep_get(pte_t *ptep) |
| { |
| return READ_ONCE(*ptep); |
| } |
| #endif |
| |
| #ifdef CONFIG_GUP_GET_PTE_LOW_HIGH |
| /* |
| * WARNING: only to be used in the get_user_pages_fast() implementation. |
| * |
| * With get_user_pages_fast(), we walk down the pagetables without taking any |
| * locks. For this we would like to load the pointers atomically, but sometimes |
| * that is not possible (e.g. without expensive cmpxchg8b on x86_32 PAE). What |
| * we do have is the guarantee that a PTE will only either go from not present |
| * to present, or present to not present or both -- it will not switch to a |
| * completely different present page without a TLB flush in between; something |
| * that we are blocking by holding interrupts off. |
| * |
| * Setting ptes from not present to present goes: |
| * |
| * ptep->pte_high = h; |
| * smp_wmb(); |
| * ptep->pte_low = l; |
| * |
| * And present to not present goes: |
| * |
| * ptep->pte_low = 0; |
| * smp_wmb(); |
| * ptep->pte_high = 0; |
| * |
| * We must ensure here that the load of pte_low sees 'l' IFF pte_high sees 'h'. |
| * We load pte_high *after* loading pte_low, which ensures we don't see an older |
| * value of pte_high. *Then* we recheck pte_low, which ensures that we haven't |
| * picked up a changed pte high. We might have gotten rubbish values from |
| * pte_low and pte_high, but we are guaranteed that pte_low will not have the |
| * present bit set *unless* it is 'l'. Because get_user_pages_fast() only |
| * operates on present ptes we're safe. |
| */ |
| static inline pte_t ptep_get_lockless(pte_t *ptep) |
| { |
| pte_t pte; |
| |
| do { |
| pte.pte_low = ptep->pte_low; |
| smp_rmb(); |
| pte.pte_high = ptep->pte_high; |
| smp_rmb(); |
| } while (unlikely(pte.pte_low != ptep->pte_low)); |
| |
| return pte; |
| } |
| #else /* CONFIG_GUP_GET_PTE_LOW_HIGH */ |
| /* |
| * We require that the PTE can be read atomically. |
| */ |
| static inline pte_t ptep_get_lockless(pte_t *ptep) |
| { |
| return ptep_get(ptep); |
| } |
| #endif /* CONFIG_GUP_GET_PTE_LOW_HIGH */ |
| |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| #ifndef __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR |
| static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| pmd_t pmd = *pmdp; |
| pmd_clear(pmdp); |
| return pmd; |
| } |
| #endif /* __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR */ |
| #ifndef __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR |
| static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm, |
| unsigned long address, |
| pud_t *pudp) |
| { |
| pud_t pud = *pudp; |
| |
| pud_clear(pudp); |
| return pud; |
| } |
| #endif /* __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR */ |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| #ifndef __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR_FULL |
| static inline pmd_t pmdp_huge_get_and_clear_full(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp, |
| int full) |
| { |
| return pmdp_huge_get_and_clear(vma->vm_mm, address, pmdp); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR_FULL |
| static inline pud_t pudp_huge_get_and_clear_full(struct mm_struct *mm, |
| unsigned long address, pud_t *pudp, |
| int full) |
| { |
| return pudp_huge_get_and_clear(mm, address, pudp); |
| } |
| #endif |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| |
| #ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL |
| static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, |
| unsigned long address, pte_t *ptep, |
| int full) |
| { |
| pte_t pte; |
| pte = ptep_get_and_clear(mm, address, ptep); |
| return pte; |
| } |
| #endif |
| |
| |
| /* |
| * If two threads concurrently fault at the same page, the thread that |
| * won the race updates the PTE and its local TLB/Cache. The other thread |
| * gives up, simply does nothing, and continues; on architectures where |
| * software can update TLB, local TLB can be updated here to avoid next page |
| * fault. This function updates TLB only, do nothing with cache or others. |
| * It is the difference with function update_mmu_cache. |
| */ |
| #ifndef __HAVE_ARCH_UPDATE_MMU_TLB |
| static inline void update_mmu_tlb(struct vm_area_struct *vma, |
| unsigned long address, pte_t *ptep) |
| { |
| } |
| #define __HAVE_ARCH_UPDATE_MMU_TLB |
| #endif |
| |
| /* |
| * Some architectures may be able to avoid expensive synchronization |
| * primitives when modifications are made to PTE's which are already |
| * not present, or in the process of an address space destruction. |
| */ |
| #ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL |
| static inline void pte_clear_not_present_full(struct mm_struct *mm, |
| unsigned long address, |
| pte_t *ptep, |
| int full) |
| { |
| pte_clear(mm, address, ptep); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH |
| extern pte_t ptep_clear_flush(struct vm_area_struct *vma, |
| unsigned long address, |
| pte_t *ptep); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH |
| extern pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp); |
| extern pud_t pudp_huge_clear_flush(struct vm_area_struct *vma, |
| unsigned long address, |
| pud_t *pudp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT |
| struct mm_struct; |
| static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep) |
| { |
| pte_t old_pte = *ptep; |
| set_pte_at(mm, address, ptep, pte_wrprotect(old_pte)); |
| } |
| #endif |
| |
| /* |
| * On some architectures hardware does not set page access bit when accessing |
| * memory page, it is responsibilty of software setting this bit. It brings |
| * out extra page fault penalty to track page access bit. For optimization page |
| * access bit can be set during all page fault flow on these arches. |
| * To be differentiate with macro pte_mkyoung, this macro is used on platforms |
| * where software maintains page access bit. |
| */ |
| #ifndef pte_savedwrite |
| #define pte_savedwrite pte_write |
| #endif |
| |
| #ifndef pte_mk_savedwrite |
| #define pte_mk_savedwrite pte_mkwrite |
| #endif |
| |
| #ifndef pte_clear_savedwrite |
| #define pte_clear_savedwrite pte_wrprotect |
| #endif |
| |
| #ifndef pmd_savedwrite |
| #define pmd_savedwrite pmd_write |
| #endif |
| |
| #ifndef pmd_mk_savedwrite |
| #define pmd_mk_savedwrite pmd_mkwrite |
| #endif |
| |
| #ifndef pmd_clear_savedwrite |
| #define pmd_clear_savedwrite pmd_wrprotect |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline void pmdp_set_wrprotect(struct mm_struct *mm, |
| unsigned long address, pmd_t *pmdp) |
| { |
| pmd_t old_pmd = *pmdp; |
| set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd)); |
| } |
| #else |
| static inline void pmdp_set_wrprotect(struct mm_struct *mm, |
| unsigned long address, pmd_t *pmdp) |
| { |
| BUILD_BUG(); |
| } |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| #ifndef __HAVE_ARCH_PUDP_SET_WRPROTECT |
| #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD |
| static inline void pudp_set_wrprotect(struct mm_struct *mm, |
| unsigned long address, pud_t *pudp) |
| { |
| pud_t old_pud = *pudp; |
| |
| set_pud_at(mm, address, pudp, pud_wrprotect(old_pud)); |
| } |
| #else |
| static inline void pudp_set_wrprotect(struct mm_struct *mm, |
| unsigned long address, pud_t *pudp) |
| { |
| BUILD_BUG(); |
| } |
| #endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */ |
| #endif |
| |
| #ifndef pmdp_collapse_flush |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| extern pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp); |
| #else |
| static inline pmd_t pmdp_collapse_flush(struct vm_area_struct *vma, |
| unsigned long address, |
| pmd_t *pmdp) |
| { |
| BUILD_BUG(); |
| return *pmdp; |
| } |
| #define pmdp_collapse_flush pmdp_collapse_flush |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT |
| extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, |
| pgtable_t pgtable); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW |
| extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp); |
| #endif |
| |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| /* |
| * This is an implementation of pmdp_establish() that is only suitable for an |
| * architecture that doesn't have hardware dirty/accessed bits. In this case we |
| * can't race with CPU which sets these bits and non-atomic aproach is fine. |
| */ |
| static inline pmd_t generic_pmdp_establish(struct vm_area_struct *vma, |
| unsigned long address, pmd_t *pmdp, pmd_t pmd) |
| { |
| pmd_t old_pmd = *pmdp; |
| set_pmd_at(vma->vm_mm, address, pmdp, pmd); |
| return old_pmd; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMDP_INVALIDATE |
| extern pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, |
| pmd_t *pmdp); |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTE_SAME |
| static inline int pte_same(pte_t pte_a, pte_t pte_b) |
| { |
| return pte_val(pte_a) == pte_val(pte_b); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PTE_UNUSED |
| /* |
| * Some architectures provide facilities to virtualization guests |
| * so that they can flag allocated pages as unused. This allows the |
| * host to transparently reclaim unused pages. This function returns |
| * whether the pte's page is unused. |
| */ |
| static inline int pte_unused(pte_t pte) |
| { |
| return 0; |
| } |
| #endif |
| |
| #ifndef pte_access_permitted |
| #define pte_access_permitted(pte, write) \ |
| (pte_present(pte) && (!(write) || pte_write(pte))) |
| #endif |
| |
| #ifndef pmd_access_permitted |
| #define pmd_access_permitted(pmd, write) \ |
| (pmd_present(pmd) && (!(write) || pmd_write(pmd))) |
| #endif |
| |
| #ifndef pud_access_permitted |
| #define pud_access_permitted(pud, write) \ |
| (pud_present(pud) && (!(write) || pud_write(pud))) |
| #endif |
| |
| #ifndef p4d_access_permitted |
| #define p4d_access_permitted(p4d, write) \ |
| (p4d_present(p4d) && (!(write) || p4d_write(p4d))) |
| #endif |
| |
| #ifndef pgd_access_permitted |
| #define pgd_access_permitted(pgd, write) \ |
| (pgd_present(pgd) && (!(write) || pgd_write(pgd))) |
| #endif |
| |
| #ifndef __HAVE_ARCH_PMD_SAME |
| static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b) |
| { |
| return pmd_val(pmd_a) == pmd_val(pmd_b); |
| } |
| |
| static inline int pud_same(pud_t pud_a, pud_t pud_b) |
| { |
| return pud_val(pud_a) == pud_val(pud_b); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_P4D_SAME |
| static inline int p4d_same(p4d_t p4d_a, p4d_t p4d_b) |
| { |
| return p4d_val(p4d_a) == p4d_val(p4d_b); |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGD_SAME |
| static inline int pgd_same(pgd_t pgd_a, pgd_t pgd_b) |
| { |
| return pgd_val(pgd_a) == pgd_val(pgd_b); |
| } |
| #endif |
| |
| /* |
| * Use set_p*_safe(), and elide TLB flushing, when confident that *no* |
| * TLB flush will be required as a result of the "set". For example, use |
| * in scenarios where it is known ahead of time that the routine is |
| * setting non-present entries, or re-setting an existing entry to the |
| * same value. Otherwise, use the typical "set" helpers and flush the |
| * TLB. |
| */ |
| #define set_pte_safe(ptep, pte) \ |
| ({ \ |
| WARN_ON_ONCE(pte_present(*ptep) && !pte_same(*ptep, pte)); \ |
| set_pte(ptep, pte); \ |
| }) |
| |
| #define set_pmd_safe(pmdp, pmd) \ |
| ({ \ |
| WARN_ON_ONCE(pmd_present(*pmdp) && !pmd_same(*pmdp, pmd)); \ |
| set_pmd(pmdp, pmd); \ |
| }) |
| |
| #define set_pud_safe(pudp, pud) \ |
| ({ \ |
| WARN_ON_ONCE(pud_present(*pudp) && !pud_same(*pudp, pud)); \ |
| set_pud(pudp, pud); \ |
| }) |
| |
| #define set_p4d_safe(p4dp, p4d) \ |
| ({ \ |
| WARN_ON_ONCE(p4d_present(*p4dp) && !p4d_same(*p4dp, p4d)); \ |
| set_p4d(p4dp, p4d); \ |
| }) |
| |
| #define set_pgd_safe(pgdp, pgd) \ |
| ({ \ |
| WARN_ON_ONCE(pgd_present(*pgdp) && !pgd_same(*pgdp, pgd)); \ |
| set_pgd(pgdp, pgd); \ |
| }) |
| |
| #ifndef __HAVE_ARCH_DO_SWAP_PAGE |
| /* |
| * Some architectures support metadata associated with a page. When a |
| * page is being swapped out, this metadata must be saved so it can be |
| * restored when the page is swapped back in. SPARC M7 and newer |
| * processors support an ADI (Application Data Integrity) tag for the |
| * page as metadata for the page. arch_do_swap_page() can restore this |
| * metadata when a page is swapped back in. |
| */ |
| static inline void arch_do_swap_page(struct mm_struct *mm, |
| struct vm_area_struct *vma, |
| unsigned long addr, |
| pte_t pte, pte_t oldpte) |
| { |
| |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_UNMAP_ONE |
| /* |
| * Some architectures support metadata associated with a page. When a |
| * page is being swapped out, this metadata must be saved so it can be |
| * restored when the page is swapped back in. SPARC M7 and newer |
| * processors support an ADI (Application Data Integrity) tag for the |
| * page as metadata for the page. arch_unmap_one() can save this |
| * metadata on a swap-out of a page. |
| */ |
| static inline int arch_unmap_one(struct mm_struct *mm, |
| struct vm_area_struct *vma, |
| unsigned long addr, |
| pte_t orig_pte) |
| { |
| return 0; |
| } |
| #endif |
| |
| /* |
| * Allow architectures to preserve additional metadata associated with |
| * swapped-out pages. The corresponding __HAVE_ARCH_SWAP_* macros and function |
| * prototypes must be defined in the arch-specific asm/pgtable.h file. |
| */ |
| #ifndef __HAVE_ARCH_PREPARE_TO_SWAP |
| static inline int arch_prepare_to_swap(struct page *page) |
| { |
| return 0; |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_SWAP_INVALIDATE |
| static inline void arch_swap_invalidate_page(int type, pgoff_t offset) |
| { |
| } |
| |
| static inline void arch_swap_invalidate_area(int type) |
| { |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_SWAP_RESTORE |
| static inline void arch_swap_restore(swp_entry_t entry, struct page *page) |
| { |
| } |
| #endif |
| |
| #ifndef __HAVE_ARCH_PGD_OFFSET_GATE |
| #define pgd_offset_gate(mm, addr) pgd_offset(mm, addr) |
| #endif |
| |
| #ifndef __HAVE_ARCH_MOVE_PTE |
| #define move_pte(pte, prot, old_addr, new_addr) (pte) |
| #endif |
| |
| #ifndef pte_accessible |
| # define pte_accessible(mm, pte) ((void)(pte), 1) |
| #endif |
| |
| #ifndef flush_tlb_fix_spurious_fault |
| #define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address) |
| #endif |
| |
| /* |
| * When walking page tables, get the address of the next boundary, |
| * or the end address of the range if that comes earlier. Although no |
| * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout. |
| */ |
| |
| #define pgd_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| |
| #ifndef p4d_addr_end |
| #define p4d_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + P4D_SIZE) & P4D_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| #endif |
| |
| #ifndef pud_addr_end |
| #define pud_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| #endif |
| |
| #ifndef pmd_addr_end |
| #define pmd_addr_end(addr, end) \ |
| ({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \ |
| (__boundary - 1 < (end) - 1)? __boundary: (end); \ |
| }) |
| #endif |
| |
| /* |
| * When walking page tables, we usually want to skip any p?d_none entries; |
| * and any p?d_bad entries - reporting the error before resetting to none. |
| * Do the tests inline, but report and clear the bad entry in mm/memory.c. |
| */ |
| void pgd_clear_bad(pgd_t *); |
| |
| #ifndef __PAGETABLE_P4D_FOLDED |
| void p4d_clear_bad(p4d_t *); |
| #else |
| #define p4d_clear_bad(p4d) do { } while (0) |
| #endif |
| |
| #ifndef __PAGETABLE_PUD_FOLDED |
| void pud_clear_bad(pud_t *); |
| #else |
| #define pud_clear_bad(p4d) do { } while (0) |
| #endif |
| |
| void pmd_clear_bad(pmd_t *); |
| |
| static inline int pgd_none_or_clear_bad(pgd_t *pgd) |
| { |
| if (pgd_none(*pgd)) |
| return 1; |
| if (unlikely(pgd_bad(*pgd))) { |
| pgd_clear_bad(pgd); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline int p4d_none_or_clear_bad(p4d_t *p4d) |
| { |
| if (p4d_none(*p4d)) |
| return 1; |
| if (unlikely(p4d_bad(*p4d))) { |
| p4d_clear_bad(p4d); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline int pud_none_or_clear_bad(pud_t *pud) |
| { |
| if (pud_none(*pud)) |
| return 1; |
| if (unlikely(pud_bad(*pud))) { |
| pud_clear_bad(pud); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline int pmd_none_or_clear_bad(pmd_t *pmd) |
| { |
| if (pmd_none(*pmd)) |
| return 1; |
| if (unlikely(pmd_bad(*pmd))) { |
| pmd_clear_bad(pmd); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static inline pte_t __ptep_modify_prot_start(struct vm_area_struct *vma, |
| unsigned long addr, |
| pte_t *ptep) |
| { |
| /* |
| * Get the current pte state, but zero it out to make it |
| * non-present, preventing the hardware from asynchronously |
| * updating it. |
| */ |
| return ptep_get_and_clear(vma->vm_mm, addr, ptep); |
| } |
| |
| static inline void __ptep_modify_prot_commit(struct vm_area_struct *vma, |
| unsigned long addr, |
| pte_t *ptep, pte_t pte) |
| { |
| /* |
| * The pte is non-present, so there's no hardware state to |
| * preserve. |
| */ |
| set_pte_at(vma->vm_mm, addr, ptep, pte); |
| } |
| |
| #ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION |
| /* |
| * Start a pte protection read-modify-write transaction, which |
| * protects against asynchronous hardware modifications to the pte. |
| * The intention is not to prevent the hardware from making pte |
| * updates, but to prevent any updates it may make from being lost. |
| * |
| * This does not protect against other software modifications of the |
| * pte; the appropriate pte lock must be held over the transation. |
| * |
| * Note that this interface is intended to be batchable, meaning that |
| * ptep_modify_prot_commit may not actually update the pte, but merely |
| * queue the update to be done at some later time. The update must be |
| * actually committed before the pte lock is released, however. |
| */ |
| static inline pte_t ptep_modify_prot_start(struct vm_area_struct *vma, |
| unsigned long addr, |
| pte_t *ptep) |
| { |
| return __ptep_modify_prot_start(vma, addr, ptep); |
| } |
| |
| /* |
| * Commit an update to a pte, leaving any hardware-controlled bits in |
| * the PTE unmodified. |
| */ |
| static inline void ptep_modify_prot_commit(struct vm_area_struct *vma, |
| unsigned long addr, |
| pte_t *ptep, pte_t old_pte, pte_t pte) |
| { |
| __ptep_modify_prot_commit(vma, addr, ptep, pte); |
| } |
| #endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */ |
| #endif /* CONFIG_MMU */ |
| |
| /* |
| * No-op macros that just return the current protection value. Defined here |
| * because these macros can be used even if CONFIG_MMU is not defined. |
| */ |
| |
| #ifndef pgprot_nx |
| #define pgprot_nx(prot) (prot) |
| #endif |
| |
| #ifndef pgprot_noncached |
| #define pgprot_noncached(prot) (prot) |
| #endif |
| |
| #ifndef pgprot_writecombine |
| #define pgprot_writecombine pgprot_noncached |
| #endif |
| |
| #ifndef pgprot_writethrough |
| #define pgprot_writethrough pgprot_noncached |
| #endif |
| |
| #ifndef pgprot_device |
| #define pgprot_device pgprot_noncached |
| #endif |
| |
| #ifdef CONFIG_MMU |
| #ifndef pgprot_modify |
| #define pgprot_modify pgprot_modify |
| static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) |
| { |
| if (pgprot_val(oldprot) == pgprot_val(pgprot_noncached(oldprot))) |
| newprot = pgprot_noncached(newprot); |
| if (pgprot_val(oldprot) == pgprot_val(pgprot_writecombine(oldprot))) |
| newprot = pgprot_writecombine(newprot); |
| if (pgprot_val(oldprot) == pgprot_val(pgprot_device(oldprot))) |
| newprot = pgprot_device(newprot); |
| return newprot; |
| } |
| #endif |
| #endif /* CONFIG_MMU */ |
| |
| #ifndef pgprot_encrypted |
| #define pgprot_encrypted(prot) (prot) |
| #endif |
| |
| #ifndef pgprot_decrypted |
| #define pgprot_decrypted(prot) (prot) |
| #endif |
| |
| /* |
| * A facility to provide lazy MMU batching. This allows PTE updates and |
| * page invalidations to be delayed until a call to leave lazy MMU mode |
| * is issued. Some architectures may benefit from doing this, and it is |
| * beneficial for both shadow and direct mode hypervisors, which may batch |
| * the PTE updates which happen during this window. Note that using this |
| * interface requires that read hazards be removed from the code. A read |
| * hazard could result in the direct mode hypervisor case, since the actual |
| * write to the page tables may not yet have taken place, so reads though |
| * a raw PTE pointer after it has been modified are not guaranteed to be |
| * up to date. This mode can only be entered and left under the protection of |
| * the page table locks for all page tables which may be modified. In the UP |
| * case, this is required so that preemption is disabled, and in the SMP case, |
| * it must synchronize the delayed page table writes properly on other CPUs. |
| */ |
| #ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE |
| #define arch_enter_lazy_mmu_mode() do {} while (0) |
| #define arch_leave_lazy_mmu_mode() do {} while (0) |
| #define arch_flush_lazy_mmu_mode() do {} while (0) |
| #endif |
| |
| /* |
| * A facility to provide batching of the reload of page tables and |
| * other process state with the actual context switch code for |
| * paravirtualized guests. By convention, only one of the batched |
| * update (lazy) modes (CPU, MMU) should be active at any given time, |
| * entry should never be nested, and entry and exits should always be |
| * paired. This is for sanity of maintaining and reasoning about the |
| * kernel code. In this case, the exit (end of the context switch) is |
| * in architecture-specific code, and so doesn't need a generic |
| * definition. |
| */ |
| #ifndef __HAVE_ARCH_START_CONTEXT_SWITCH |
| #define arch_start_context_switch(prev) do {} while (0) |
| #endif |
| |
| #ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY |
| #ifndef CONFIG_ARCH_ENABLE_THP_MIGRATION |
| static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline int pmd_swp_soft_dirty(pmd_t pmd) |
| { |
| return 0; |
| } |
| |
| static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| #endif |
| #else /* !CONFIG_HAVE_ARCH_SOFT_DIRTY */ |
| static inline int pte_soft_dirty(pte_t pte) |
| { |
| return 0; |
| } |
| |
| static inline int pmd_soft_dirty(pmd_t pmd) |
| { |
| return 0; |
| } |
| |
| static inline pte_t pte_mksoft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pmd_t pmd_mksoft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline pte_t pte_clear_soft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pmd_t pmd_clear_soft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline pte_t pte_swp_mksoft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline int pte_swp_soft_dirty(pte_t pte) |
| { |
| return 0; |
| } |
| |
| static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) |
| { |
| return pte; |
| } |
| |
| static inline pmd_t pmd_swp_mksoft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| |
| static inline int pmd_swp_soft_dirty(pmd_t pmd) |
| { |
| return 0; |
| } |
| |
| static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd) |
| { |
| return pmd; |
| } |
| #endif |
| |
| #ifndef __HAVE_PFNMAP_TRACKING |
| /* |
| * Interfaces that can be used by architecture code to keep track of |
| * memory type of pfn mappings specified by the remap_pfn_range, |
| * vmf_insert_pfn. |
| */ |
| |
| /* |
| * track_pfn_remap is called when a _new_ pfn mapping is being established |
| * by remap_pfn_range() for physical range indicated by pfn and size. |
| */ |
| static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, |
| unsigned long pfn, unsigned long addr, |
| unsigned long size) |
| { |
| return 0; |
| } |
| |
| /* |
| * track_pfn_insert is called when a _new_ single pfn is established |
| * by vmf_insert_pfn(). |
| */ |
| static inline void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, |
| pfn_t pfn) |
| { |
| } |
| |
| /* |
| * track_pfn_copy is called when vma that is covering the pfnmap gets |
| * copied through copy_page_range(). |
| */ |
| static inline int track_pfn_copy(struct vm_area_struct *vma) |
| { |
| return 0; |
| } |
| |
| /* |
| * untrack_pfn is called while unmapping a pfnmap for a region. |
| * untrack can be called for a specific region indicated by pfn and size or |
| * can be for the entire vma (in which case pfn, size are zero). |
| */ |
| static inline void untrack_pfn(struct vm_area_struct *vma, |
| unsigned long pfn, unsigned long size) |
| { |
| } |
| |
| /* |
| * untrack_pfn_moved is called while mremapping a pfnmap for a new region. |
| */ |
| static inline void untrack_pfn_moved(struct vm_area_struct *vma) |
| { |
| } |
| #else |
| extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, |
| unsigned long pfn, unsigned long addr, |
| unsigned long size); |
| extern void track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, |
| pfn_t pfn); |
| extern int track_pfn_copy(struct vm_area_struct *vma); |
| extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, |
| unsigned long size); |
| extern void untrack_pfn_moved(struct vm_area_struct *vma); |
| #endif |
| |
| #ifdef __HAVE_COLOR_ZERO_PAGE |
| static inline int is_zero_pfn(unsigned long pfn) |
| { |
| extern unsigned long zero_pfn; |
| unsigned long offset_from_zero_pfn = pfn - zero_pfn; |
| return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); |
| } |
| |
| #define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) |
| |
| #else |
| static inline int is_zero_pfn(unsigned long pfn) |
| { |
| extern unsigned long zero_pfn; |
| return pfn == zero_pfn; |
| } |
| |
| static inline unsigned long my_zero_pfn(unsigned long addr) |
| { |
| extern unsigned long zero_pfn; |
| return zero_pfn; |
| } |
| #endif |
| |
| #ifdef CONFIG_MMU |
| |
| #ifndef CONFIG_TRANSPARENT_HUGEPAGE |
| static inline int pmd_trans_huge(pmd_t pmd) |
| { |
| return 0; |
| } |
| #ifndef pmd_write |
| static inline int pmd_write(pmd_t pmd) |
| { |
| BUG(); |
| return 0; |
| } |
| #endif /* pmd_write */ |
| #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| |
| #ifndef pud_write |
| static inline int pud_write(pud_t pud) |
| { |
| BUG(); |
| return 0; |
| } |
| #endif /* pud_write */ |
| |
| #if !defined(CONFIG_ARCH_HAS_PTE_DEVMAP) || !defined(CONFIG_TRANSPARENT_HUGEPAGE) |
| static inline int pmd_devmap(pmd_t pmd) |
| { |
| return 0; |
| } |
| static inline int pud_devmap(pud_t pud) |
| { |
| return 0; |
| } |
| static inline int pgd_devmap(pgd_t pgd) |
| { |
| return 0; |
| } |
| #endif |
| |
| #if !defined(CONFIG_TRANSPARENT_HUGEPAGE) || \ |
| (defined(CONFIG_TRANSPARENT_HUGEPAGE) && \ |
| !defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) |
| static inline int pud_trans_huge(pud_t pud) |
| { |
| return 0; |
| } |
| #endif |
| |
| /* See pmd_none_or_trans_huge_or_clear_bad for discussion. */ |
| static inline int pud_none_or_trans_huge_or_dev_or_clear_bad(pud_t *pud) |
| { |
| pud_t pudval = READ_ONCE(*pud); |
| |
| if (pud_none(pudval) || pud_trans_huge(pudval) || pud_devmap(pudval)) |
| return 1; |
| if (unlikely(pud_bad(pudval))) { |
| pud_clear_bad(pud); |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* See pmd_trans_unstable for discussion. */ |
| static inline int pud_trans_unstable(pud_t *pud) |
| { |
| #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \ |
| defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) |
| return pud_none_or_trans_huge_or_dev_or_clear_bad(pud); |
| #else |
| return 0; |
| #endif |
| } |
| |
| #ifndef pmd_read_atomic |
| static inline pmd_t pmd_read_atomic(pmd_t *pmdp) |
| { |
| /* |
| * Depend on compiler for an atomic pmd read. NOTE: this is |
| * only going to work, if the pmdval_t isn't larger than |
| * an unsigned long. |
| */ |
| return *pmdp; |
| } |
| #endif |
| |
| #ifndef arch_needs_pgtable_deposit |
| #define arch_needs_pgtable_deposit() (false) |
| #endif |
| /* |
| * This function is meant to be used by sites walking pagetables with |
| * the mmap_lock held in read mode to protect against MADV_DONTNEED and |
| * transhuge page faults. MADV_DONTNEED can convert a transhuge pmd |
| * into a null pmd and the transhuge page fault can convert a null pmd |
| * into an hugepmd or into a regular pmd (if the hugepage allocation |
| * fails). While holding the mmap_lock in read mode the pmd becomes |
| * stable and stops changing under us only if it's not null and not a |
| * transhuge pmd. When those races occurs and this function makes a |
| * difference vs the standard pmd_none_or_clear_bad, the result is |
| * undefined so behaving like if the pmd was none is safe (because it |
| * can return none anyway). The compiler level barrier() is critically |
| * important to compute the two checks atomically on the same pmdval. |
| * |
| * For 32bit kernels with a 64bit large pmd_t this automatically takes |
| * care of reading the pmd atomically to avoid SMP race conditions |
| * against pmd_populate() when the mmap_lock is hold for reading by the |
| * caller (a special atomic read not done by "gcc" as in the generic |
| * version above, is also needed when THP is disabled because the page |
| * fault can populate the pmd from under us). |
| */ |
| static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd) |
| { |
| pmd_t pmdval = pmd_read_atomic(pmd); |
| /* |
| * The barrier will stabilize the pmdval in a register or on |
| * the stack so that it will stop changing under the code. |
| * |
| * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE, |
| * pmd_read_atomic is allowed to return a not atomic pmdval |
| * (for example pointing to an hugepage that has never been |
| * mapped in the pmd). The below checks will only care about |
| * the low part of the pmd with 32bit PAE x86 anyway, with the |
| * exception of pmd_none(). So the important thing is that if |
| * the low part of the pmd is found null, the high part will |
| * be also null or the pmd_none() check below would be |
| * confused. |
| */ |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| barrier(); |
| #endif |
| /* |
| * !pmd_present() checks for pmd migration entries |
| * |
| * The complete check uses is_pmd_migration_entry() in linux/swapops.h |
| * But using that requires moving current function and pmd_trans_unstable() |
| * to linux/swapops.h to resovle dependency, which is too much code move. |
| * |
| * !pmd_present() is equivalent to is_pmd_migration_entry() currently, |
| * because !pmd_present() pages can only be under migration not swapped |
| * out. |
| * |
| * pmd_none() is preseved for future condition checks on pmd migration |
| * entries and not confusing with this function name, although it is |
| * redundant with !pmd_present(). |
| */ |
| if (pmd_none(pmdval) || pmd_trans_huge(pmdval) || |
| (IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION) && !pmd_present(pmdval))) |
| return 1; |
| if (unlikely(pmd_bad(pmdval))) { |
| pmd_clear_bad(pmd); |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* |
| * This is a noop if Transparent Hugepage Support is not built into |
| * the kernel. Otherwise it is equivalent to |
| * pmd_none_or_trans_huge_or_clear_bad(), and shall only be called in |
| * places that already verified the pmd is not none and they want to |
| * walk ptes while holding the mmap sem in read mode (write mode don't |
| * need this). If THP is not enabled, the pmd can't go away under the |
| * code even if MADV_DONTNEED runs, but if THP is enabled we need to |
| * run a pmd_trans_unstable before walking the ptes after |
| * split_huge_pmd returns (because it may have run when the pmd become |
| * null, but then a page fault can map in a THP and not a regular page). |
| */ |
| static inline int pmd_trans_unstable(pmd_t *pmd) |
| { |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| return pmd_none_or_trans_huge_or_clear_bad(pmd); |
| #else |
| return 0; |
| #endif |
| } |
| |
| /* |
| * the ordering of these checks is important for pmds with _page_devmap set. |
| * if we check pmd_trans_unstable() first we will trip the bad_pmd() check |
| * inside of pmd_none_or_trans_huge_or_clear_bad(). this will end up correctly |
| * returning 1 but not before it spams dmesg with the pmd_clear_bad() output. |
| */ |
| static inline int pmd_devmap_trans_unstable(pmd_t *pmd) |
| { |
| return pmd_devmap(*pmd) || pmd_trans_unstable(pmd); |
| } |
| |
| #ifndef CONFIG_NUMA_BALANCING |
| /* |
| * Technically a PTE can be PROTNONE even when not doing NUMA balancing but |
| * the only case the kernel cares is for NUMA balancing and is only ever set |
| * when the VMA is accessible. For PROT_NONE VMAs, the PTEs are not marked |
| * _PAGE_PROTNONE so by default, implement the helper as "always no". It |
| * is the responsibility of the caller to distinguish between PROT_NONE |
| * protections and NUMA hinting fault protections. |
| */ |
| static inline int pte_protnone(pte_t pte) |
| { |
| return 0; |
| } |
| |
| static inline int pmd_protnone(pmd_t pmd) |
| { |
| return 0; |
| } |
| #endif /* CONFIG_NUMA_BALANCING */ |
| |
| #endif /* CONFIG_MMU */ |
| |
| #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP |
| |
| #ifndef __PAGETABLE_P4D_FOLDED |
| int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot); |
| int p4d_clear_huge(p4d_t *p4d); |
| #else |
| static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot) |
| { |
| return 0; |
| } |
| static inline int p4d_clear_huge(p4d_t *p4d) |
| { |
| return 0; |
| } |
| #endif /* !__PAGETABLE_P4D_FOLDED */ |
| |
| int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot); |
| int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot); |
| int pud_clear_huge(pud_t *pud); |
| int pmd_clear_huge(pmd_t *pmd); |
| int p4d_free_pud_page(p4d_t *p4d, unsigned long addr); |
| int pud_free_pmd_page(pud_t *pud, unsigned long addr); |
| int pmd_free_pte_page(pmd_t *pmd, unsigned long addr); |
| #else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */ |
| static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot) |
| { |
| return 0; |
| } |
| static inline int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot) |
| { |
| return 0; |
| } |
| static inline int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot) |
| { |
| return 0; |
| } |
| static inline int p4d_clear_huge(p4d_t *p4d) |
| { |
| return 0; |
| } |
| static inline int pud_clear_huge(pud_t *pud) |
| { |
| return 0; |
| } |
| static inline int pmd_clear_huge(pmd_t *pmd) |
| { |
| return 0; |
| } |
| static inline int p4d_free_pud_page(p4d_t *p4d, unsigned long addr) |
| { |
| return 0; |
| } |
| static inline int pud_free_pmd_page(pud_t *pud, unsigned long addr) |
| { |
| return 0; |
| } |
| static inline int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) |
| { |
| return 0; |
| } |
| #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ |
| |
| #ifndef __HAVE_ARCH_FLUSH_PMD_TLB_RANGE |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| /* |
| * ARCHes with special requirements for evicting THP backing TLB entries can |
| * implement this. Otherwise also, it can help optimize normal TLB flush in |
| * THP regime. Stock flush_tlb_range() typically has optimization to nuke the |
| * entire TLB if flush span is greater than a threshold, which will |
| * likely be true for a single huge page. Thus a single THP flush will |
| * invalidate the entire TLB which is not desirable. |
| * e.g. see arch/arc: flush_pmd_tlb_range |
| */ |
| #define flush_pmd_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end) |
| #define flush_pud_tlb_range(vma, addr, end) flush_tlb_range(vma, addr, end) |
| #else |
| #define flush_pmd_tlb_range(vma, addr, end) BUILD_BUG() |
| #define flush_pud_tlb_range(vma, addr, end) BUILD_BUG() |
| #endif |
| #endif |
| |
| struct file; |
| int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, |
| unsigned long size, pgprot_t *vma_prot); |
| |
| #ifndef CONFIG_X86_ESPFIX64 |
| static inline void init_espfix_bsp(void) { } |
| #endif |
| |
| extern void __init pgtable_cache_init(void); |
| |
| #ifndef __HAVE_ARCH_PFN_MODIFY_ALLOWED |
| static inline bool pfn_modify_allowed(unsigned long pfn, pgprot_t prot) |
| { |
| return true; |
| } |
| |
| static inline bool arch_has_pfn_modify_check(void) |
| { |
| return false; |
| } |
| #endif /* !_HAVE_ARCH_PFN_MODIFY_ALLOWED */ |
| |
| /* |
| * Architecture PAGE_KERNEL_* fallbacks |
| * |
| * Some architectures don't define certain PAGE_KERNEL_* flags. This is either |
| * because they really don't support them, or the port needs to be updated to |
| * reflect the required functionality. Below are a set of relatively safe |
| * fallbacks, as best effort, which we can count on in lieu of the architectures |
| * not defining them on their own yet. |
| */ |
| |
| #ifndef PAGE_KERNEL_RO |
| # define PAGE_KERNEL_RO PAGE_KERNEL |
| #endif |
| |
| #ifndef PAGE_KERNEL_EXEC |
| # define PAGE_KERNEL_EXEC PAGE_KERNEL |
| #endif |
| |
| /* |
| * Page Table Modification bits for pgtbl_mod_mask. |
| * |
| * These are used by the p?d_alloc_track*() set of functions an in the generic |
| * vmalloc/ioremap code to track at which page-table levels entries have been |
| * modified. Based on that the code can better decide when vmalloc and ioremap |
| * mapping changes need to be synchronized to other page-tables in the system. |
| */ |
| #define __PGTBL_PGD_MODIFIED 0 |
| #define __PGTBL_P4D_MODIFIED 1 |
| #define __PGTBL_PUD_MODIFIED 2 |
| #define __PGTBL_PMD_MODIFIED 3 |
| #define __PGTBL_PTE_MODIFIED 4 |
| |
| #define PGTBL_PGD_MODIFIED BIT(__PGTBL_PGD_MODIFIED) |
| #define PGTBL_P4D_MODIFIED BIT(__PGTBL_P4D_MODIFIED) |
| #define PGTBL_PUD_MODIFIED BIT(__PGTBL_PUD_MODIFIED) |
| #define PGTBL_PMD_MODIFIED BIT(__PGTBL_PMD_MODIFIED) |
| #define PGTBL_PTE_MODIFIED BIT(__PGTBL_PTE_MODIFIED) |
| |
| /* Page-Table Modification Mask */ |
| typedef unsigned int pgtbl_mod_mask; |
| |
| #endif /* !__ASSEMBLY__ */ |
| |
| #if !defined(MAX_POSSIBLE_PHYSMEM_BITS) && !defined(CONFIG_64BIT) |
| #ifdef CONFIG_PHYS_ADDR_T_64BIT |
| /* |
| * ZSMALLOC needs to know the highest PFN on 32-bit architectures |
| * with physical address space extension, but falls back to |
| * BITS_PER_LONG otherwise. |
| */ |
| #error Missing MAX_POSSIBLE_PHYSMEM_BITS definition |
| #else |
| #define MAX_POSSIBLE_PHYSMEM_BITS 32 |
| #endif |
| #endif |
| |
| #ifndef has_transparent_hugepage |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| #define has_transparent_hugepage() 1 |
| #else |
| #define has_transparent_hugepage() 0 |
| #endif |
| #endif |
| |
| /* |
| * On some architectures it depends on the mm if the p4d/pud or pmd |
| * layer of the page table hierarchy is folded or not. |
| */ |
| #ifndef mm_p4d_folded |
| #define mm_p4d_folded(mm) __is_defined(__PAGETABLE_P4D_FOLDED) |
| #endif |
| |
| #ifndef mm_pud_folded |
| #define mm_pud_folded(mm) __is_defined(__PAGETABLE_PUD_FOLDED) |
| #endif |
| |
| #ifndef mm_pmd_folded |
| #define mm_pmd_folded(mm) __is_defined(__PAGETABLE_PMD_FOLDED) |
| #endif |
| |
| #ifndef p4d_offset_lockless |
| #define p4d_offset_lockless(pgdp, pgd, address) p4d_offset(&(pgd), address) |
| #endif |
| #ifndef pud_offset_lockless |
| #define pud_offset_lockless(p4dp, p4d, address) pud_offset(&(p4d), address) |
| #endif |
| #ifndef pmd_offset_lockless |
| #define pmd_offset_lockless(pudp, pud, address) pmd_offset(&(pud), address) |
| #endif |
| |
| /* |
| * p?d_leaf() - true if this entry is a final mapping to a physical address. |
| * This differs from p?d_huge() by the fact that they are always available (if |
| * the architecture supports large pages at the appropriate level) even |
| * if CONFIG_HUGETLB_PAGE is not defined. |
| * Only meaningful when called on a valid entry. |
| */ |
| #ifndef pgd_leaf |
| #define pgd_leaf(x) 0 |
| #endif |
| #ifndef p4d_leaf |
| #define p4d_leaf(x) 0 |
| #endif |
| #ifndef pud_leaf |
| #define pud_leaf(x) 0 |
| #endif |
| #ifndef pmd_leaf |
| #define pmd_leaf(x) 0 |
| #endif |
| |
| #ifndef pgd_leaf_size |
| #define pgd_leaf_size(x) (1ULL << PGDIR_SHIFT) |
| #endif |
| #ifndef p4d_leaf_size |
| #define p4d_leaf_size(x) P4D_SIZE |
| #endif |
| #ifndef pud_leaf_size |
| #define pud_leaf_size(x) PUD_SIZE |
| #endif |
| #ifndef pmd_leaf_size |
| #define pmd_leaf_size(x) PMD_SIZE |
| #endif |
| #ifndef pte_leaf_size |
| #define pte_leaf_size(x) PAGE_SIZE |
| #endif |
| |
| #endif /* _LINUX_PGTABLE_H */ |