Re: [PATCH] filemap: remove obsolete comment in lock_page

From: Matthew Wilcox
Date: Mon Apr 04 2022 - 11:33:03 EST


On Sat, Apr 02, 2022 at 02:22:18PM +0800, Miaohe Lin wrote:
> lock_page needs the caller to have a reference on the page->mapping inode
> due to sync_page. Also lock_page_nosync is introduced which does not do a
> sync_page via commit db37648cd6ce ("[PATCH] mm: non syncing lock_page()").
> But commit 7eaceaccab5f ("block: remove per-queue plugging") kills off the
> old plugging along with aops->sync_page() and lock_page_nosync. So there
> is no need to have a reference on the page->mapping inode when calling
> lock_page anymore. Remove this obsolete and confusing comment.
>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>

Thanks. I'll fix up the changelog (some of the tenses are a little
strange) and take this through my pagecache tree.

> include/linux/pagemap.h | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
> index 993994cd943a..8dfe8e49c427 100644
> --- a/include/linux/pagemap.h
> +++ b/include/linux/pagemap.h
> @@ -908,9 +908,6 @@ static inline void folio_lock(struct folio *folio)
> __folio_lock(folio);
> }
>
> -/*
> - * lock_page may only be called if we have the page's inode pinned.
> - */
> static inline void lock_page(struct page *page)
> {
> struct folio *folio;
> --
> 2.23.0
>