From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99C98C2D0C6 for ; Fri, 27 Dec 2019 10:45:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 68BA020882 for ; Fri, 27 Dec 2019 10:45:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726607AbfL0KpO (ORCPT ); Fri, 27 Dec 2019 05:45:14 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:8630 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726270AbfL0KpN (ORCPT ); Fri, 27 Dec 2019 05:45:13 -0500 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 07909F06EFC9B69146BE; Fri, 27 Dec 2019 18:45:11 +0800 (CST) Received: from szvp000203569.huawei.com (10.120.216.130) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.439.0; Fri, 27 Dec 2019 18:45:04 +0800 From: Chao Yu To: CC: , , , Chao Yu Subject: [PATCH] f2fs: fix to add swap extent correctly Date: Fri, 27 Dec 2019 18:44:56 +0800 Message-ID: <20191227104456.24528-1-yuchao0@huawei.com> X-Mailer: git-send-email 2.18.0.rc1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.120.216.130] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As Youling reported in mailing list: https://www.linuxquestions.org/questions/linux-newbie-8/the-file-system-f2fs-is-broken-4175666043/ https://www.linux.org/threads/the-file-system-f2fs-is-broken.26490/ There is a test case can corrupt f2fs image: - dd if=/dev/zero of=/swapfile bs=1M count=4096 - chmod 600 /swapfile - mkswap /swapfile - swapon --discard /swapfile The root cause is f2fs_swap_activate() intends to return zero value to setup_swap_extents() to enable SWP_FS mode (swap file goes through fs), in this flow, setup_swap_extents() setups swap extent with wrong block address range, result in discard_swap() erasing incorrect address. Because f2fs_swap_activate() has pinned swapfile, its data block address will not change, it's safe to let swap to handle IO through raw device, so we can get rid of SWAP_FS mode and initial swap extents inside f2fs_swap_activate(), by this way, later discard_swap() can trim in right address range. Fixes: 4969c06a0d83 ("f2fs: support swap file w/ DIO") Signed-off-by: Chao Yu --- fs/f2fs/data.c | 32 +++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 19cd03450066..ee4d3d284379 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -3608,7 +3608,8 @@ int f2fs_migrate_page(struct address_space *mapping, #ifdef CONFIG_SWAP /* Copied from generic_swapfile_activate() to check any holes */ -static int check_swap_activate(struct file *swap_file, unsigned int max) +static int check_swap_activate(struct swap_info_struct *sis, + struct file *swap_file, sector_t *span) { struct address_space *mapping = swap_file->f_mapping; struct inode *inode = mapping->host; @@ -3619,6 +3620,8 @@ static int check_swap_activate(struct file *swap_file, unsigned int max) sector_t last_block; sector_t lowest_block = -1; sector_t highest_block = 0; + int nr_extents = 0; + int ret; blkbits = inode->i_blkbits; blocks_per_page = PAGE_SIZE >> blkbits; @@ -3630,7 +3633,8 @@ static int check_swap_activate(struct file *swap_file, unsigned int max) probe_block = 0; page_no = 0; last_block = i_size_read(inode) >> blkbits; - while ((probe_block + blocks_per_page) <= last_block && page_no < max) { + while ((probe_block + blocks_per_page) <= last_block && + page_no < sis->max) { unsigned block_in_page; sector_t first_block; @@ -3670,13 +3674,27 @@ static int check_swap_activate(struct file *swap_file, unsigned int max) highest_block = first_block; } + /* + * We found a PAGE_SIZE-length, PAGE_SIZE-aligned run of blocks + */ + ret = add_swap_extent(sis, page_no, 1, first_block); + if (ret < 0) + goto out; + nr_extents += ret; page_no++; probe_block += blocks_per_page; reprobe: continue; } - return 0; - + ret = nr_extents; + *span = 1 + highest_block - lowest_block; + if (page_no == 0) + page_no = 1; /* force Empty message */ + sis->max = page_no; + sis->pages = page_no - 1; + sis->highest_bit = page_no - 1; +out: + return ret; bad_bmap: pr_err("swapon: swapfile has holes\n"); return -EINVAL; @@ -3701,14 +3719,14 @@ static int f2fs_swap_activate(struct swap_info_struct *sis, struct file *file, if (f2fs_disable_compressed_file(inode)) return -EINVAL; - ret = check_swap_activate(file, sis->max); - if (ret) + ret = check_swap_activate(sis, file, span); + if (ret < 0) return ret; set_inode_flag(inode, FI_PIN_FILE); f2fs_precache_extents(inode); f2fs_update_time(F2FS_I_SB(inode), REQ_TIME); - return 0; + return ret; } static void f2fs_swap_deactivate(struct file *file) -- 2.18.0.rc1