diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 36 |
1 files changed, 33 insertions, 3 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 0f9389f9d1f8..6ecd1045113b 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -326,7 +326,7 @@ static struct attribute *hugepage_attr[] = { &defrag_attr.attr, &use_zero_page_attr.attr, &hpage_pmd_size_attr.attr, -#if defined(CONFIG_SHMEM) && defined(CONFIG_TRANSPARENT_HUGE_PAGECACHE) +#ifdef CONFIG_SHMEM &shmem_enabled_attr.attr, #endif #ifdef CONFIG_DEBUG_VM @@ -597,6 +597,7 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, if (mem_cgroup_try_charge_delay(page, vma->vm_mm, gfp, &memcg, true)) { put_page(page); count_vm_event(THP_FAULT_FALLBACK); + count_vm_event(THP_FAULT_FALLBACK_CHARGE); return VM_FAULT_FALLBACK; } @@ -1043,6 +1044,14 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, ret = -EAGAIN; pmd = *src_pmd; + /* + * Make sure the _PAGE_UFFD_WP bit is cleared if the new VMA + * does not have the VM_UFFD_WP, which means that the uffd + * fork event is not enabled. + */ + if (!(vma->vm_flags & VM_UFFD_WP)) + pmd = pmd_clear_uffd_wp(pmd); + #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION if (unlikely(is_swap_pmd(pmd))) { swp_entry_t entry = pmd_to_swp_entry(pmd); @@ -1446,6 +1455,7 @@ alloc: put_page(page); ret |= VM_FAULT_FALLBACK; count_vm_event(THP_FAULT_FALLBACK); + count_vm_event(THP_FAULT_FALLBACK_CHARGE); goto out; } @@ -1977,13 +1987,16 @@ bool move_huge_pmd(struct vm_area_struct *vma, unsigned long old_addr, * - HPAGE_PMD_NR is protections changed and TLB flush necessary */ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, pgprot_t newprot, int prot_numa) + unsigned long addr, pgprot_t newprot, unsigned long cp_flags) { struct mm_struct *mm = vma->vm_mm; spinlock_t *ptl; pmd_t entry; bool preserve_write; int ret; + bool prot_numa = cp_flags & MM_CP_PROT_NUMA; + bool uffd_wp = cp_flags & MM_CP_UFFD_WP; + bool uffd_wp_resolve = cp_flags & MM_CP_UFFD_WP_RESOLVE; ptl = __pmd_trans_huge_lock(pmd, vma); if (!ptl) @@ -2050,6 +2063,17 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, entry = pmd_modify(entry, newprot); if (preserve_write) entry = pmd_mk_savedwrite(entry); + if (uffd_wp) { + entry = pmd_wrprotect(entry); + entry = pmd_mkuffd_wp(entry); + } else if (uffd_wp_resolve) { + /* + * Leave the write bit to be handled by PF interrupt + * handler, then things like COW could be properly + * handled. + */ + entry = pmd_clear_uffd_wp(entry); + } ret = HPAGE_PMD_NR; set_pmd_at(mm, addr, pmd, entry); BUG_ON(vma_is_anonymous(vma) && !preserve_write && pmd_write(entry)); @@ -2198,7 +2222,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, struct page *page; pgtable_t pgtable; pmd_t old_pmd, _pmd; - bool young, write, soft_dirty, pmd_migration = false; + bool young, write, soft_dirty, pmd_migration = false, uffd_wp = false; unsigned long addr; int i; @@ -2273,6 +2297,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, write = is_write_migration_entry(entry); young = false; soft_dirty = pmd_swp_soft_dirty(old_pmd); + uffd_wp = pmd_swp_uffd_wp(old_pmd); } else { page = pmd_page(old_pmd); if (pmd_dirty(old_pmd)) @@ -2280,6 +2305,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, write = pmd_write(old_pmd); young = pmd_young(old_pmd); soft_dirty = pmd_soft_dirty(old_pmd); + uffd_wp = pmd_uffd_wp(old_pmd); } VM_BUG_ON_PAGE(!page_count(page), page); page_ref_add(page, HPAGE_PMD_NR - 1); @@ -2304,6 +2330,8 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = swp_entry_to_pte(swp_entry); if (soft_dirty) entry = pte_swp_mksoft_dirty(entry); + if (uffd_wp) + entry = pte_swp_mkuffd_wp(entry); } else { entry = mk_pte(page + i, READ_ONCE(vma->vm_page_prot)); entry = maybe_mkwrite(entry, vma); @@ -2313,6 +2341,8 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = pte_mkold(entry); if (soft_dirty) entry = pte_mksoft_dirty(entry); + if (uffd_wp) + entry = pte_mkuffd_wp(entry); } pte = pte_offset_map(&_pmd, addr); BUG_ON(!pte_none(*pte)); |