Move the body of inet6_rt_notify() to __inet6_rt_notify() and give it
the deletion reason. inet6_rt_notify() keeps its prototype, so the
route addition path does not change.
Add inet6_rt_del_notify() and call it from fib6_del_route().
RTA_DEL_REASON now reaches user space on RTM_DELROUTE for routes the
kernel deleted on its own.
Signed-off-by: Yuyang Huang <sigefriedhyy@gmail.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260808005642.26901-7-sigefriedhyy@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>