net/mlx5e: Modify and restore TC rules for IPSec TX rules

net/mlx5e: Modify and restore TC rules for IPSec TX rules

After IPsec policy/state TX rules are added, any TC flow rule, which
forwards packets to uplink, is modified to forward to IPsec TX tables.
As these tables are destroyed dynamically, whenever there is no
reference to them, the destinations of this kind of rules must be
restored to uplink.

There is a special case for packet encapsulation, as the
packet_reformat_id in the extended destination is used to reformat
packets, but only for the VPORT destination. To forward packet to
IPsec table and do encapsulation in one FTE, move the
packet_reformat_id to flow context, instead of using the extended
destination. As a limitation, multiple encapsulations with table
forwarding, and one together with other VPORT destinations, are not
allowed, so add a check when offloading TC rules.

TC rules are not allowed before IPsec TX rule is added, so only need
to restore TC rules after flush IPSec TX rules. As they are saved in
the vport_rep rhashtables, we walk all the rules in the rhashtables,
and find TC rules with destinations pointing to IPsec tables, and
modify them one by one. To avoid concurrent issue, this handling is
done under the protection of eswitch mode_lock.

Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/7bcb2c7e2ecf0e0d06b095c8dcc6a37ea7f02faf.1690802064.git.leon@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>