From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 26 Mar 2002 13:02:12 +0000 (GMT) From: Hugh Dickins Subject: Re: [PATCH] updated radix-tree pagecache In-Reply-To: <3CA045BC.AA75D788@zip.com.au> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Christoph Hellwig , Christoph Rohland , linux-mm@kvack.org, linux-kernel@vger.kernel.org, velco@fadata.bg List-ID: On Tue, 26 Mar 2002, Andrew Morton wrote: > > Aside: This is not related to ratcache: shmem_getpage_locked() is > setting PG_dirty but not adding the page to mapping->dirty_pages. Is > this intended? Yes. It used to be the case that if a tmpfs file page got on to mapping->dirty_pages, fsync on that file would never escape from filemap_fdatasync if there was no swap. Hence also "SetPageDirty" in several places which originally said "set_page_dirty". Nowadays the "if (!PageLaunder(page)) return fail_writepage(page);" at the start of shmem_writepage would prevent that hang, and prevents a subtler tmpfs file corruption we realized later on. But the dirty_pages list is still a waste of time for tmpfs: its data does not need to be committed to stable storage. Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/