Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161443AbWJKVMr (ORCPT ); Wed, 11 Oct 2006 17:12:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161453AbWJKVJ4 (ORCPT ); Wed, 11 Oct 2006 17:09:56 -0400 Received: from mail.kroah.org ([69.55.234.183]:50083 "EHLO perch.kroah.org") by vger.kernel.org with ESMTP id S1161451AbWJKVJa (ORCPT ); Wed, 11 Oct 2006 17:09:30 -0400 Date: Wed, 11 Oct 2006 14:08:56 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, torvalds@osdl.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , akpm@osdl.org, alan@lxorguk.ukuu.org.uk, nickpiggin@yahoo.com.au, Chuck Lever , Peter Zijlstra , Greg Kroah-Hartman Subject: [patch 61/67] invalidate_inode_pages2(): ignore page refcounts Message-ID: <20061011210856.GJ16627@kroah.com> References: <20061011204756.642936754@quad.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="invalidate_inode_pages2-ignore-page-refcounts.patch" In-Reply-To: <20061011210310.GA16627@kroah.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2950 Lines: 92 -stable review patch. If anyone has any objections, please let us know. ------------------ From: Andrew Morton The recent fix to invalidate_inode_pages() (git commit 016eb4a) managed to unfix invalidate_inode_pages2(). The problem is that various bits of code in the kernel can take transient refs on pages: the page scanner will do this when inspecting a batch of pages, and the lru_cache_add() batching pagevecs also hold a ref. Net result is transient failures in invalidate_inode_pages2(). This affects NFS directory invalidation (observed) and presumably also block-backed direct-io (not yet reported). Fix it by reverting invalidate_inode_pages2() back to the old version which ignores the page refcounts. We may come up with something more clever later, but for now we need a 2.6.18 fix for NFS. Cc: Chuck Lever Cc: Nick Piggin Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/truncate.c | 34 ++++++++++++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) --- linux-2.6.18.orig/mm/truncate.c +++ linux-2.6.18/mm/truncate.c @@ -270,9 +270,39 @@ unsigned long invalidate_inode_pages(str { return invalidate_mapping_pages(mapping, 0, ~0UL); } - EXPORT_SYMBOL(invalidate_inode_pages); +/* + * This is like invalidate_complete_page(), except it ignores the page's + * refcount. We do this because invalidate_inode_pages2() needs stronger + * invalidation guarantees, and cannot afford to leave pages behind because + * shrink_list() has a temp ref on them, or because they're transiently sitting + * in the lru_cache_add() pagevecs. + */ +static int +invalidate_complete_page2(struct address_space *mapping, struct page *page) +{ + if (page->mapping != mapping) + return 0; + + if (PagePrivate(page) && !try_to_release_page(page, 0)) + return 0; + + write_lock_irq(&mapping->tree_lock); + if (PageDirty(page)) + goto failed; + + BUG_ON(PagePrivate(page)); + __remove_from_page_cache(page); + write_unlock_irq(&mapping->tree_lock); + ClearPageUptodate(page); + page_cache_release(page); /* pagecache ref */ + return 1; +failed: + write_unlock_irq(&mapping->tree_lock); + return 0; +} + /** * invalidate_inode_pages2_range - remove range of pages from an address_space * @mapping: the address_space @@ -339,7 +369,7 @@ int invalidate_inode_pages2_range(struct } } was_dirty = test_clear_page_dirty(page); - if (!invalidate_complete_page(mapping, page)) { + if (!invalidate_complete_page2(mapping, page)) { if (was_dirty) set_page_dirty(page); ret = -EIO; -- - 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/