Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966303AbWKNUIx (ORCPT ); Tue, 14 Nov 2006 15:08:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S966306AbWKNUIw (ORCPT ); Tue, 14 Nov 2006 15:08:52 -0500 Received: from mx1.redhat.com ([66.187.233.31]:1961 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S966303AbWKNUIv (ORCPT ); Tue, 14 Nov 2006 15:08:51 -0500 From: David Howells Subject: [PATCH 03/19] FS-Cache: Release page->private after failed readahead Date: Tue, 14 Nov 2006 20:06:28 +0000 To: torvalds@osdl.org, akpm@osdl.org, sds@tycho.nsa.gov, trond.myklebust@fys.uio.no Cc: dhowells@redhat.com, selinux@tycho.nsa.gov, linux-kernel@vger.kernel.org, aviro@redhat.com, steved@redhat.com Message-Id: <20061114200628.12943.90169.stgit@warthog.cambridge.redhat.com> In-Reply-To: <20061114200621.12943.18023.stgit@warthog.cambridge.redhat.com> References: <20061114200621.12943.18023.stgit@warthog.cambridge.redhat.com> Content-Type: text/plain; charset=utf-8; format=fixed Content-Transfer-Encoding: 8bit User-Agent: StGIT/0.10 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3007 Lines: 94 The attached patch causes read_cache_pages() to release page-private data on a page for which add_to_page_cache() fails or the filler function fails. This permits pages with caching references associated with them to be cleaned up. The invalidatepage() address space op is called (indirectly) to do the honours. Signed-Off-By: David Howells --- mm/readahead.c | 46 ++++++++++++++++++++++++++++++++++++++-------- 1 files changed, 38 insertions(+), 8 deletions(-) diff --git a/mm/readahead.c b/mm/readahead.c index 23cb61a..c64f366 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -14,6 +14,7 @@ #include #include #include #include +#include void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page) { @@ -118,6 +119,41 @@ static inline unsigned long get_next_ra_ #define list_to_page(head) (list_entry((head)->prev, struct page, lru)) +/* + * see if a page needs releasing upon read_cache_pages() failure + * - the caller of read_cache_pages() may have set PG_private before calling, + * such as the NFS fs marking pages that are cached locally on disk, thus we + * need to give the fs a chance to clean up in the event of an error + */ +static void read_cache_pages_invalidate_page(struct address_space *mapping, + struct page *page) +{ + if (PagePrivate(page)) { + if (TestSetPageLocked(page)) + BUG(); + page->mapping = mapping; + do_invalidatepage(page, 0); + page->mapping = NULL; + unlock_page(page); + } + page_cache_release(page); +} + +/* + * release a list of pages, invalidating them first if need be + */ +static void read_cache_pages_invalidate_pages(struct address_space *mapping, + struct list_head *pages) +{ + struct page *victim; + + while (!list_empty(pages)) { + victim = list_to_page(pages); + list_del(&victim->lru); + read_cache_pages_invalidate_page(mapping, victim); + } +} + /** * read_cache_pages - populate an address space with some pages & start reads against them * @mapping: the address_space @@ -141,20 +177,14 @@ int read_cache_pages(struct address_spac page = list_to_page(pages); list_del(&page->lru); if (add_to_page_cache(page, mapping, page->index, GFP_KERNEL)) { - page_cache_release(page); + read_cache_pages_invalidate_page(mapping, page); continue; } ret = filler(data, page); if (!pagevec_add(&lru_pvec, page)) __pagevec_lru_add(&lru_pvec); if (ret) { - while (!list_empty(pages)) { - struct page *victim; - - victim = list_to_page(pages); - list_del(&victim->lru); - page_cache_release(victim); - } + read_cache_pages_invalidate_pages(mapping, pages); break; } } - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/