From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 4.14 047/170] f2fs: fix race between write_checkpoint and write_begin Date: Mon, 28 Jan 2019 11:09:57 -0500 Message-ID: <20190128161200.55107-47-sashal@kernel.org> References: <20190128161200.55107-1-sashal@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-2.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1go9Xz-0002ep-Hh for linux-f2fs-devel@lists.sourceforge.net; Mon, 28 Jan 2019 16:14:07 +0000 Received: from mail.kernel.org ([198.145.29.99]) by sfi-mx-3.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1go9Xu-003UJ0-02 for linux-f2fs-devel@lists.sourceforge.net; Mon, 28 Jan 2019 16:14:07 +0000 In-Reply-To: <20190128161200.55107-1-sashal@kernel.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sasha Levin , Jaegeuk Kim , linux-f2fs-devel@lists.sourceforge.net From: Sheng Yong [ Upstream commit 2866fb16d67992195b0526d19e65acb6640fb87f ] The following race could lead to inconsistent SIT bitmap: Task A Task B ====== ====== f2fs_write_checkpoint block_operations f2fs_lock_all down_write(node_change) down_write(node_write) ... sync ... up_write(node_change) f2fs_file_write_iter set_inode_flag(FI_NO_PREALLOC) ...... f2fs_write_begin(index=0, has inline data) prepare_write_begin __do_map_lock(AIO) => down_read(node_change) f2fs_convert_inline_page => update SIT __do_map_lock(AIO) => up_read(node_change) f2fs_flush_sit_entries <= inconsistent SIT finish write checkpoint sudden-power-off If SPO occurs after checkpoint is finished, SIT bitmap will be set incorrectly. Signed-off-by: Sheng Yong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/data.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index c68b319b07aa..3d37124eb63e 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1880,6 +1880,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi, bool locked = false; struct extent_info ei = {0,0,0}; int err = 0; + int flag; /* * we already allocated all the blocks, so we don't need to get @@ -1889,9 +1890,15 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi, !is_inode_flag_set(inode, FI_NO_PREALLOC)) return 0; + /* f2fs_lock_op avoids race between write CP and convert_inline_page */ + if (f2fs_has_inline_data(inode) && pos + len > MAX_INLINE_DATA(inode)) + flag = F2FS_GET_BLOCK_DEFAULT; + else + flag = F2FS_GET_BLOCK_PRE_AIO; + if (f2fs_has_inline_data(inode) || (pos & PAGE_MASK) >= i_size_read(inode)) { - __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true); + __do_map_lock(sbi, flag, true); locked = true; } restart: @@ -1929,6 +1936,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi, f2fs_put_dnode(&dn); __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true); + WARN_ON(flag != F2FS_GET_BLOCK_PRE_AIO); locked = true; goto restart; } @@ -1942,7 +1950,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi, f2fs_put_dnode(&dn); unlock_out: if (locked) - __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false); + __do_map_lock(sbi, flag, false); return err; } -- 2.19.1