From mboxrd@z Thu Jan 1 00:00:00 1970 From: jiangyiwen Date: Wed, 9 Sep 2015 09:55:16 +0800 Subject: [Ocfs2-devel] [PATCH] ocfs2: Fill-in the unused portion of the block with zeros by dio_zero_block() Message-ID: <55EF9184.5090007@huawei.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com A simplified test case is (this case from Ryan): 1) dd if=/dev/zero of=/mnt/hello bs=512 count=1 oflag=direct; 2) truncate /mnt/hello -s 2097152 file 'hello' is not exist before test. After this command, file 'hello' should be all zero. But 512~4096 is some random data. Setting bh state to new when get a new block, if so, direct_io_worker()->dio_zero_block() will fill-in the unused portion of the block with zero. Signed-off-by: Yiwen Jiang --- fs/ocfs2/aops.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 1a35c61..bd106b9 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -581,6 +581,7 @@ static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock, ret = -EIO; goto bail; } + set_buffer_new(bh_result); } /* -- 1.8.3.4