From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 47AA4329F21 for ; Thu, 11 Sep 2025 03:34:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757561655; cv=none; b=X2NlnbwcVAhYamp8Qns+T0ukMSdVXOOSFhKd7UHnOghK2gOVK0Rtg2M9FuoRN5vhkULjC8QAFuU04tGgU0aepbLDtQO7GZ9WTEdpStXnoO4tDSGv/ILn073yrZyk/sHB+jfWG4FM7nN0Z/cNXiwrFnQcZU98cgXIJ+wnbaMUl10= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757561655; c=relaxed/simple; bh=aFRYFllGC8iv5Ps3xo9d7orAvONw/RgdtXrnk9kpVho=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=QUPlP0mXS5WrWfSLPpRMQES0vbAFglPzRYyDbnxfjTFtGCb4omOIqggtjPnAOSRb6S32F7y+CSlWj7uzqxUndqDgzHQByYdwGiW6R/96n7JKwLPNOoCiiJqazfLzOyCVguUgQ9Lo7NKrg8cZZPMb9jMKOFZDNAN71YCdxe0jZX0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lW26JSl0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lW26JSl0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 498FCC4CEF1; Thu, 11 Sep 2025 03:34:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757561654; bh=aFRYFllGC8iv5Ps3xo9d7orAvONw/RgdtXrnk9kpVho=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=lW26JSl0bz6t2mNzplcTpLOlMuxyLvG/ik2fNGT9J7G0RZpLVtWgqFaaAGFiKl3Q2 vJXJNpXvtQCLYjJ32bS38ttJSsRMfLWs2md56Bddc6iPRNoOpwJo/SetXAj/olV6qI YULBl5+5LwLCdP9fHaBIKL5MEb71kbRJ0E+cVw7VNL86ydnrmpHPjOnppl8se0tJjP ZCAzE9KVN9RIth8ASP/lPskJuKZ6poEczULAQDbkL38gjj8aIRmE5gL8BhjRb1ESl7 uQTZdDJCU0UoUeKva7dZTJ5Nv+4puN/2qOxWpv6DX9u79V1xknnfYtvWp1iWxbmL/U XNOHuzQJ6nB6g== Message-ID: Date: Thu, 11 Sep 2025 11:34:11 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: chao@kernel.org, bintian.wang@honor.com, feng.han@honor.com, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [f2fs-dev] [PATCH 1/2] f2fs: fix wrong extent_info data for precache extents To: wangzijie , jaegeuk@kernel.org References: <20250910135835.2751574-1-wangzijie1@honor.com> Content-Language: en-US From: Chao Yu In-Reply-To: <20250910135835.2751574-1-wangzijie1@honor.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/10/25 21:58, wangzijie wrote: > When the data layout is like this: > dnode1: dnode2: > [0] A [0] NEW_ADDR > [1] A+1 [1] 0x0 > ... .... > [1016] A+1016 > [1017] B (B!=A+1017) [1017] 0x0 > > We can build this kind of layout by following steps(with i_extra_isize:36): > ./f2fs_io write 1 0 1881 rand dsync testfile > ./f2fs_io write 1 1881 1 rand buffered testfile > ./f2fs_io fallocate 0 7708672 4096 testfile > > And when we map first data block in dnode2, we will get wrong extent_info data: > map->m_len = 1 > ofs = start_pgofs - map->m_lblk = 1882 - 1881 = 1 > > ei.fofs = start_pgofs = 1882 > ei.len = map->m_len - ofs = 1 - 1 = 0 Hi Zijie, I tried to reproduce w/ below steps: f2fs_io write 1 0 1881 rand dsync testfile f2fs_io write 1 1881 1 rand buffered testfile f2fs_io fallocate 0 7708672 4096 testfile umount mount f2fs_io precache_extents testfile f2fs_io-921 [013] ..... 1049.855817: f2fs_lookup_start: dev = (253,16), pino = 3, name:testfile, flags:65537 f2fs_io-921 [013] ..... 1049.855870: f2fs_submit_read_bio: dev = (253,16)/(253,16), rw = READ(), DATA, sector = 139280, size = 4096 f2fs_io-921 [013] ..... 1049.856116: f2fs_submit_folio_bio: dev = (253,16), ino = 1, folio_index = 0x5, oldaddr = 0x5553, newaddr = 0x5553, rw = READ(), type = HOT_NODE f2fs_io-921 [013] ..... 1049.856147: f2fs_submit_read_bio: dev = (253,16)/(253,16), rw = READ(), NODE, sector = 174744, size = 4096 f2fs_io-921 [013] ..... 1049.856273: f2fs_iget: dev = (253,16), ino = 5, pino = 3, i_mode = 0x81ed, i_size = 7712768, i_nlink = 1, i_blocks = 15080, i_advise = 0x0 f2fs_io-921 [013] ..... 1049.856305: f2fs_lookup_end: dev = (253,16), pino = 3, name:testfile, ino:5, err:0 f2fs_io-921 [013] ..... 1049.856316: f2fs_lookup_extent_tree_start: dev = (253,16), ino = 5, pgofs = 0, type = Read f2fs_io-921 [013] ..... 1049.856317: f2fs_lookup_read_extent_tree_end: dev = (253,16), ino = 5, pgofs = 0, read_ext_info(fofs: 0, len: 512, blk: 1055744) f2fs_io-921 [013] ..... 1049.856317: f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 0, start blkaddr = 0x101c00, len = 0x200, flags = 2, seg_type = 8, may_create = 0, multidevice = 0, flag = 6, err = 0 f2fs_io-921 [013] ..... 1049.856318: f2fs_lookup_extent_tree_start: dev = (253,16), ino = 5, pgofs = 512, type = Read f2fs_io-921 [013] ..... 1049.856318: f2fs_lookup_read_extent_tree_end: dev = (253,16), ino = 5, pgofs = 512, read_ext_info(fofs: 0, len: 0, blk: 0) f2fs_io-921 [013] ..... 1049.856323: f2fs_update_read_extent_tree_range: dev = (253,16), ino = 5, pgofs = 512, len = 352, blkaddr = 18432, c_len = 0 f2fs_io-921 [013] ..... 1049.856328: f2fs_submit_folio_bio: dev = (253,16), ino = 1, folio_index = 0x6, oldaddr = 0x5556, newaddr = 0x5556, rw = READ(), type = HOT_NODE f2fs_io-921 [013] ..... 1049.856329: f2fs_submit_read_bio: dev = (253,16)/(253,16), rw = READ(), NODE, sector = 174768, size = 4096 f2fs_io-921 [021] ..... 1049.856968: f2fs_update_read_extent_tree_range: dev = (253,16), ino = 5, pgofs = 864, len = 160, blkaddr = 18784, c_len = 0 f2fs_io-921 [021] ..... 1049.857002: f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 512, start blkaddr = 0x4800, len = 0x200, flags = 2, seg_type = 8, may_create = 0, multidevice = 0, flag = 6, err = 0 f2fs_io-921 [021] ..... 1049.857003: f2fs_lookup_extent_tree_start: dev = (253,16), ino = 5, pgofs = 1025, type = Read f2fs_io-921 [021] ..... 1049.857004: f2fs_lookup_read_extent_tree_end: dev = (253,16), ino = 5, pgofs = 1025, read_ext_info(fofs: 0, len: 0, blk: 0) f2fs_io-921 [021] ..... 1049.857010: f2fs_update_read_extent_tree_range: dev = (253,16), ino = 5, pgofs = 1025, len = 511, blkaddr = 19457, c_len = 0 f2fs_io-921 [021] ..... 1049.857011: f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 1025, start blkaddr = 0x4c01, len = 0x1ff, flags = 2, seg_type = 8, may_create = 0, multidevice = 0, flag = 6, err = 0 f2fs_io-921 [021] ..... 1049.857012: f2fs_lookup_extent_tree_start: dev = (253,16), ino = 5, pgofs = 1537, type = Read f2fs_io-921 [021] ..... 1049.857012: f2fs_lookup_read_extent_tree_end: dev = (253,16), ino = 5, pgofs = 1537, read_ext_info(fofs: 0, len: 0, blk: 0) f2fs_io-921 [021] ..... 1049.857016: f2fs_update_read_extent_tree_range: dev = (253,16), ino = 5, pgofs = 1537, len = 344, blkaddr = 20993, c_len = 0 f2fs_io-921 [021] ..... 1049.857016: f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 1537, start blkaddr = 0x5201, len = 0x158, flags = 2, seg_type = 8, may_create = 0, multidevice = 0, flag = 6, err = 0 f2fs_io-921 [021] ..... 1049.857017: f2fs_lookup_extent_tree_start: dev = (253,16), ino = 5, pgofs = 1882, type = Read f2fs_io-921 [021] ..... 1049.857017: f2fs_lookup_read_extent_tree_end: dev = (253,16), ino = 5, pgofs = 1882, read_ext_info(fofs: 0, len: 0, blk: 0) f2fs_io-921 [021] ..... 1049.857024: f2fs_submit_folio_bio: dev = (253,16), ino = 1, folio_index = 0x7, oldaddr = 0x5555, newaddr = 0x5555, rw = READ(), type = HOT_NODE f2fs_io-921 [021] ..... 1049.857026: f2fs_submit_read_bio: dev = (253,16)/(253,16), rw = READ(), NODE, sector = 174760, size = 4096 f2fs_io-921 [021] ..... 1049.857156: f2fs_map_blocks: dev = (253,16), ino = 5, file offset = 1882, start blkaddr = 0x5201, len = 0x0, flags = 0, seg_type = 8, may_create = 0, multidevice = 0, flag = 6, err = 0 It seems f2fs_update_read_extent_tree_range() won't insert a zero-sized extent? Or am I missing something? Thanks, > > Fix it by skipping updating this kind of extent info. > > Signed-off-by: wangzijie > --- > fs/f2fs/data.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 7961e0ddf..b8bb71852 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -1649,6 +1649,9 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag) > > switch (flag) { > case F2FS_GET_BLOCK_PRECACHE: > + if (__is_valid_data_blkaddr(map->m_pblk) && > + start_pgofs - map->m_lblk == map->m_len) > + map->m_flags &= ~F2FS_MAP_MAPPED; > goto sync_out; > case F2FS_GET_BLOCK_BMAP: > map->m_pblk = 0;