From 4b8554c527f3cfa183f6c06d231a9387873205a0 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Fri, 28 Jan 2022 14:29:43 -0500 Subject: mm/rmap: Convert try_to_migrate() to folios Convert the callers to pass a folio and the try_to_migrate_one() worker to use a folio throughout. Fixes an assumption that a folio must be <= PMD size. Signed-off-by: Matthew Wilcox (Oracle) --- include/linux/rmap.h | 2 +- mm/huge_memory.c | 4 ++-- mm/migrate.c | 6 ++++-- mm/migrate_device.c | 6 ++++-- mm/rmap.c | 59 +++++++++++++++++++++++++++------------------------- 5 files changed, 42 insertions(+), 35 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index a0c5c38c733f..e6e935c81414 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -193,7 +193,7 @@ static inline void page_dup_rmap(struct page *page, bool compound) int folio_referenced(struct folio *, int is_locked, struct mem_cgroup *memcg, unsigned long *vm_flags); -void try_to_migrate(struct page *page, enum ttu_flags flags); +void try_to_migrate(struct folio *folio, enum ttu_flags flags); void try_to_unmap(struct folio *, enum ttu_flags flags); int make_device_exclusive_range(struct mm_struct *mm, unsigned long start, diff --git a/mm/huge_memory.c b/mm/huge_memory.c index de684427f79c..7df1934d6528 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2262,8 +2262,8 @@ static void unmap_page(struct page *page) * pages can simply be left unmapped, then faulted back on demand. * If that is ever changed (perhaps for mlock), update remap_page(). */ - if (PageAnon(page)) - try_to_migrate(page, ttu_flags); + if (folio_test_anon(folio)) + try_to_migrate(folio, ttu_flags); else try_to_unmap(folio, ttu_flags | TTU_IGNORE_MLOCK); diff --git a/mm/migrate.c b/mm/migrate.c index 358bc311caaa..6ed85a5d1be5 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -912,6 +912,7 @@ out: static int __unmap_and_move(struct page *page, struct page *newpage, int force, enum migrate_mode mode) { + struct folio *folio = page_folio(page); int rc = -EAGAIN; bool page_was_mapped = false; struct anon_vma *anon_vma = NULL; @@ -1015,7 +1016,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage, /* Establish migration ptes */ VM_BUG_ON_PAGE(PageAnon(page) && !PageKsm(page) && !anon_vma, page); - try_to_migrate(page, 0); + try_to_migrate(folio, 0); page_was_mapped = true; } @@ -1165,6 +1166,7 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, enum migrate_mode mode, int reason, struct list_head *ret) { + struct folio *src = page_folio(hpage); int rc = -EAGAIN; int page_was_mapped = 0; struct page *new_hpage; @@ -1241,7 +1243,7 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, ttu |= TTU_RMAP_LOCKED; } - try_to_migrate(hpage, ttu); + try_to_migrate(src, ttu); page_was_mapped = 1; if (mapping_locked) diff --git a/mm/migrate_device.c b/mm/migrate_device.c index 0326b901d2fd..b2c611d4bdb2 100644 --- a/mm/migrate_device.c +++ b/mm/migrate_device.c @@ -333,6 +333,7 @@ static void migrate_vma_unmap(struct migrate_vma *migrate) for (i = 0; i < npages; i++) { struct page *page = migrate_pfn_to_page(migrate->src[i]); + struct folio *folio; if (!page) continue; @@ -356,8 +357,9 @@ static void migrate_vma_unmap(struct migrate_vma *migrate) put_page(page); } - if (page_mapped(page)) - try_to_migrate(page, 0); + folio = page_folio(page); + if (folio_mapped(folio)) + try_to_migrate(folio, 0); if (page_mapped(page) || !migrate_vma_check_page(page)) { if (!is_zone_device_page(page)) { diff --git a/mm/rmap.c b/mm/rmap.c index cf6e3de9d2f7..8497da29193c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1706,7 +1706,7 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, { struct folio *folio = page_folio(page); struct mm_struct *mm = vma->vm_mm; - DEFINE_PAGE_VMA_WALK(pvmw, page, vma, address, 0); + DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, address, 0); pte_t pteval; struct page *subpage; bool ret = true; @@ -1740,7 +1740,7 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, range.end = vma_address_end(&pvmw); mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, vma->vm_mm, address, range.end); - if (PageHuge(page)) { + if (folio_test_hugetlb(folio)) { /* * If sharing is possible, start and end will be adjusted * accordingly. @@ -1754,21 +1754,24 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION /* PMD-mapped THP migration entry */ if (!pvmw.pte) { - VM_BUG_ON_PAGE(PageHuge(page) || - !PageTransCompound(page), page); + subpage = folio_page(folio, + pmd_pfn(*pvmw.pmd) - folio_pfn(folio)); + VM_BUG_ON_FOLIO(folio_test_hugetlb(folio) || + !folio_test_pmd_mappable(folio), folio); - set_pmd_migration_entry(&pvmw, page); + set_pmd_migration_entry(&pvmw, subpage); continue; } #endif /* Unexpected PMD-mapped THP? */ - VM_BUG_ON_PAGE(!pvmw.pte, page); + VM_BUG_ON_FOLIO(!pvmw.pte, folio); - subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte); + subpage = folio_page(folio, + pte_pfn(*pvmw.pte) - folio_pfn(folio)); address = pvmw.address; - if (PageHuge(page) && !PageAnon(page)) { + if (folio_test_hugetlb(folio) && !folio_test_anon(folio)) { /* * To call huge_pmd_unshare, i_mmap_rwsem must be * held in write mode. Caller needs to explicitly @@ -1806,15 +1809,15 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, flush_cache_page(vma, address, pte_pfn(*pvmw.pte)); pteval = ptep_clear_flush(vma, address, pvmw.pte); - /* Move the dirty bit to the page. Now the pte is gone. */ + /* Set the dirty flag on the folio now the pte is gone. */ if (pte_dirty(pteval)) - set_page_dirty(page); + folio_mark_dirty(folio); /* Update high watermark before we lower rss */ update_hiwater_rss(mm); - if (is_zone_device_page(page)) { - unsigned long pfn = page_to_pfn(page); + if (folio_is_zone_device(folio)) { + unsigned long pfn = folio_pfn(folio); swp_entry_t entry; pte_t swp_pte; @@ -1850,16 +1853,16 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, * changed when hugepage migrations to device private * memory are supported. */ - subpage = page; - } else if (PageHWPoison(page)) { + subpage = &folio->page; + } else if (PageHWPoison(subpage)) { pteval = swp_entry_to_pte(make_hwpoison_entry(subpage)); - if (PageHuge(page)) { - hugetlb_count_sub(compound_nr(page), mm); + if (folio_test_hugetlb(folio)) { + hugetlb_count_sub(folio_nr_pages(folio), mm); set_huge_swap_pte_at(mm, address, pvmw.pte, pteval, vma_mmu_pagesize(vma)); } else { - dec_mm_counter(mm, mm_counter(page)); + dec_mm_counter(mm, mm_counter(&folio->page)); set_pte_at(mm, address, pvmw.pte, pteval); } @@ -1874,7 +1877,7 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, * migration) will not expect userfaults on already * copied pages. */ - dec_mm_counter(mm, mm_counter(page)); + dec_mm_counter(mm, mm_counter(&folio->page)); /* We have to invalidate as we cleared the pte */ mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); @@ -1920,10 +1923,10 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, * * See Documentation/vm/mmu_notifier.rst */ - page_remove_rmap(subpage, vma, PageHuge(page)); + page_remove_rmap(subpage, vma, folio_test_hugetlb(folio)); if (vma->vm_flags & VM_LOCKED) mlock_page_drain(smp_processor_id()); - put_page(page); + folio_put(folio); } mmu_notifier_invalidate_range_end(&range); @@ -1933,13 +1936,13 @@ static bool try_to_migrate_one(struct page *page, struct vm_area_struct *vma, /** * try_to_migrate - try to replace all page table mappings with swap entries - * @page: the page to replace page table entries for + * @folio: the folio to replace page table entries for * @flags: action and flags * - * Tries to remove all the page table entries which are mapping this page and - * replace them with special swap entries. Caller must hold the page lock. + * Tries to remove all the page table entries which are mapping this folio and + * replace them with special swap entries. Caller must hold the folio lock. */ -void try_to_migrate(struct page *page, enum ttu_flags flags) +void try_to_migrate(struct folio *folio, enum ttu_flags flags) { struct rmap_walk_control rwc = { .rmap_one = try_to_migrate_one, @@ -1956,7 +1959,7 @@ void try_to_migrate(struct page *page, enum ttu_flags flags) TTU_SYNC))) return; - if (is_zone_device_page(page) && !is_device_private_page(page)) + if (folio_is_zone_device(folio) && !folio_is_device_private(folio)) return; /* @@ -1967,13 +1970,13 @@ void try_to_migrate(struct page *page, enum ttu_flags flags) * locking requirements of exec(), migration skips * temporary VMAs until after exec() completes. */ - if (!PageKsm(page) && PageAnon(page)) + if (!folio_test_ksm(folio) && folio_test_anon(folio)) rwc.invalid_vma = invalid_migration_vma; if (flags & TTU_RMAP_LOCKED) - rmap_walk_locked(page, &rwc); + rmap_walk_locked(&folio->page, &rwc); else - rmap_walk(page, &rwc); + rmap_walk(&folio->page, &rwc); } #ifdef CONFIG_DEVICE_PRIVATE -- cgit v1.2.3