net: hns3: fix reuse conflict of the rx page

net: hns3: fix reuse conflict of the rx page

In the current rx page reuse handling process, the rx page buffer may
have conflict between driver and stack in high-pressure scenario.

To fix this problem, we need to check whether the page is only owned
by driver at the begin and at the end of a page to make sure there is
no reuse conflict between driver and stack when desc_cb->page_offset
is rollbacked to zero or increased.

Fixes: fa7711b888f2 ("net: hns3: optimize the rx page reuse handling process")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>