From patchwork Sat May 2 00:48:40 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jaegeuk Kim X-Patchwork-Id: 6313581 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 5F2CC9F32B for ; Sat, 2 May 2015 00:52:01 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 97C1820386 for ; Sat, 2 May 2015 00:52:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B61B8200DB for ; Sat, 2 May 2015 00:51:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752839AbbEBAv4 (ORCPT ); Fri, 1 May 2015 20:51:56 -0400 Received: from mail.kernel.org ([198.145.29.136]:50780 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752241AbbEBAte (ORCPT ); Fri, 1 May 2015 20:49:34 -0400 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2778C203B4; Sat, 2 May 2015 00:49:33 +0000 (UTC) Received: from localhost (mobile-166-171-250-177.mycingular.net [166.171.250.177]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 34F95203AF; Sat, 2 May 2015 00:49:32 +0000 (UTC) From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Cc: Jaegeuk Kim Subject: [PATCH 13/19] f2fs: fix race on allocating and deallocating a dentry block Date: Fri, 1 May 2015 17:48:40 -0700 Message-Id: <1430527726-68547-13-git-send-email-jaegeuk@kernel.org> X-Mailer: git-send-email 2.1.1 In-Reply-To: <1430527726-68547-1-git-send-email-jaegeuk@kernel.org> References: <1430527726-68547-1-git-send-email-jaegeuk@kernel.org> X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP There are two threads: f2fs_delete_entry() get_new_data_page() f2fs_reserve_block() dn.blkaddr = XXX lock_page(dentry_block) truncate_hole() dn.blkaddr = NULL unlock_page(dentry_block) lock_page(dentry_block) fill the block from XXX address add new dentries unlock_page(dentry_block) Later, f2fs_write_data_page() will truncate the dentry_block, since its block address is NULL. The reason for this was due to the wrong lock order. In this case, we should do f2fs_reserve_block() after locking its dentry block. Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 81d1fd5..9ba30b4 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1076,20 +1076,22 @@ struct page *get_new_data_page(struct inode *inode, struct page *page; struct dnode_of_data dn; int err; +repeat: + page = grab_cache_page(mapping, index); + if (!page) + return ERR_PTR(-ENOMEM); set_new_dnode(&dn, inode, ipage, NULL, 0); err = f2fs_reserve_block(&dn, index); - if (err) + if (err) { + f2fs_put_page(page, 1); return ERR_PTR(err); -repeat: - page = grab_cache_page(mapping, index); - if (!page) { - err = -ENOMEM; - goto put_err; } + if (!ipage) + f2fs_put_dnode(&dn); if (PageUptodate(page)) - return page; + goto got_it; if (dn.data_blkaddr == NEW_ADDR) { zero_user_segment(page, 0, PAGE_CACHE_SIZE); @@ -1104,20 +1106,19 @@ repeat: }; err = f2fs_submit_page_bio(&fio); if (err) - goto put_err; + return ERR_PTR(err); lock_page(page); if (unlikely(!PageUptodate(page))) { f2fs_put_page(page, 1); - err = -EIO; - goto put_err; + return ERR_PTR(-EIO); } if (unlikely(page->mapping != mapping)) { f2fs_put_page(page, 1); goto repeat; } } - +got_it: if (new_i_size && i_size_read(inode) < ((index + 1) << PAGE_CACHE_SHIFT)) { i_size_write(inode, ((index + 1) << PAGE_CACHE_SHIFT)); @@ -1125,10 +1126,6 @@ repeat: set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR); } return page; - -put_err: - f2fs_put_dnode(&dn); - return ERR_PTR(err); } static int __allocate_data_block(struct dnode_of_data *dn)