ext4: add mask of ext4 flags to swap

ext4: add mask of ext4 flags to swap

commit abdc644e8cbac2e9b19763680e5a7cf9bab2bee7 upstream.

The reason is that while swapping two inode, we swap the flags too.
Some flags such as EXT4_JOURNAL_DATA_FL can really confuse the things
since we're not resetting the address operations structure.  The
simplest way to keep things sane is to restrict the flags that can be
swapped.

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>