diff --git a/mm/migrate.c b/mm/migrate.c index 6d7774ef0e6c107b2262a265d8e453e297151568..7b44ebdf2d2684a1dac8ab413592d39c5e775e92 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -722,7 +722,7 @@ static int fallback_migrate_page(struct address_space *mapping, * MIGRATEPAGE_SUCCESS - success */ static int move_to_new_page(struct page *newpage, struct page *page, - int page_was_mapped, enum migrate_mode mode) + enum migrate_mode mode) { struct address_space *mapping; int rc; @@ -755,19 +755,21 @@ static int move_to_new_page(struct page *newpage, struct page *page, * space which also has its own migratepage callback. This * is the most common path for page migration. */ - rc = mapping->a_ops->migratepage(mapping, - newpage, page, mode); + rc = mapping->a_ops->migratepage(mapping, newpage, page, mode); else rc = fallback_migrate_page(mapping, newpage, page, mode); - if (rc != MIGRATEPAGE_SUCCESS) { + /* + * When successful, old pagecache page->mapping must be cleared before + * page is freed; but stats require that PageAnon be left as PageAnon. + */ + if (rc == MIGRATEPAGE_SUCCESS) { + set_page_memcg(page, NULL); + if (!PageAnon(page)) + page->mapping = NULL; + } else { set_page_memcg(newpage, NULL); newpage->mapping = NULL; - } else { - set_page_memcg(page, NULL); - if (page_was_mapped) - remove_migration_ptes(page, newpage); - page->mapping = NULL; } return rc; } @@ -902,10 +904,11 @@ static int __unmap_and_move(struct page *page, struct page *newpage, } if (!page_mapped(page)) - rc = move_to_new_page(newpage, page, page_was_mapped, mode); + rc = move_to_new_page(newpage, page, mode); - if (rc && page_was_mapped) - remove_migration_ptes(page, page); + if (page_was_mapped) + remove_migration_ptes(page, + rc == MIGRATEPAGE_SUCCESS ? newpage : page); out_unlock_both: unlock_page(newpage); @@ -1066,10 +1069,11 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, } if (!page_mapped(hpage)) - rc = move_to_new_page(new_hpage, hpage, page_was_mapped, mode); + rc = move_to_new_page(new_hpage, hpage, mode); - if (rc != MIGRATEPAGE_SUCCESS && page_was_mapped) - remove_migration_ptes(hpage, hpage); + if (page_was_mapped) + remove_migration_ptes(hpage, + rc == MIGRATEPAGE_SUCCESS ? new_hpage : hpage); unlock_page(new_hpage);