ocfs2_zero_range_for_truncate() can try to zero pages beyond current
inode size despite the fact that underlying blocks should be already
zeroed out and writeback will skip writing such pages anyway.  Avoid the
pointless work.

Link: https://lkml.kernel.org/r/20211025151332.11301-2-jack@suse.czSigned-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>