mlxsw: spectrum_acl: Implement region migration according to hints

If the hints are returned, the migration should be started. For that to
happen, there is a need to create a second physical region in TCAM with
new ERP set by passing the hints and then move chunk by chunk,
entry by entry.

During the transition, two lookups will occur. One in old region and
another in new region. The highest priority rule will be chosen.

In an unlikely case that the migration will fail and also rollback to
original region will fail the vregion will become in bad state.
Everything will work, only no future rehash will be possible. In a
follow-up work, this can be resolved by trying to resume the rollback
in delayed work and repair the vregion.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_acl_tcam.h

@@ -17,6 +17,8 @@ struct mlxsw_sp_acl_tcam {
 	unsigned long *used_groups;  /* bit array */
 	unsigned int max_groups;
 	unsigned int max_group_size;
+	struct list_head vregion_list;
+	u32 vregion_rehash_intrvl;   /* ms */
 	unsigned long priv[0];
 	/* priv has to be always the last item */
 };