ocfs2: unlock inode if deleting inode from orphan fails

When doing append direct io cleanup, if deleting inode fails, it goes
out without unlocking inode, which will cause the inode deadlock.

This issue was introduced by commit cf1776a9e834 ("ocfs2: fix a tiny
race when truncate dio orohaned entry").

Signed-off-by: Guozhonghua <guozhonghua@h3c.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reviewed-by: Gang He <ghe@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>	[4.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2/aops.c

@@ -956,6 +956,7 @@ static ssize_t ocfs2_direct_IO_write(struct kiocb *iocb,
 		tmp_ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh,
 				update_isize, end);
 		if (tmp_ret < 0) {
+			ocfs2_inode_unlock(inode, 1);
 			ret = tmp_ret;
 			mlog_errno(ret);
 			brelse(di_bh);