Re: [RFC PATCH 6/9] iomap: use set/clear_fs_page_private

Matthew Wilcox
2020-04-27T00:26:35Z

On Sun, Apr 26, 2020 at 11:49:22PM +0200, Guoqing Jiang wrote:
> @@ -59,24 +59,18 @@ iomap_page_create(struct inode *inode, struct page *page)
> * migrate_page_move_mapping() assumes that pages with private data have
> * their count elevated by 1.
> */
> - get_page(page);
> - set_page_private(page, (unsigned long)iop);
> - SetPagePrivate(page);
> - return iop;
> + return (struct iomap_page *)set_fs_page_private(page, iop);
> }

This cast is unnecessary. void * will be automatically cast to the
appropriate pointer type.

> @@ -556,11 +550,9 @@ iomap_migrate_page(struct address_space *mapping, struct page *newpage,
>
> if (page_has_private(page)) {
> ClearPagePrivate(page);
> - get_page(newpage);
> - set_page_private(newpage, page_private(page));
> + set_fs_page_private(newpage, (void *)page_private(page));
> set_page_private(page, 0);
> put_page(page);
> - SetPagePrivate(newpage);
> }

Same comment here as for the btrfs migrate page that Dave reviewed.