skbuff: Rename 'offload_mr_fwd_mark' to 'offload_l3_fwd_mark'

Commit abf4bb6b ("skbuff: Add the offload_mr_fwd_mark field") added
the 'offload_mr_fwd_mark' field to indicate that a packet has already
undergone L3 multicast routing by a capable device. The field is used to
prevent the kernel from forwarding a packet through a netdev through
which the device has already forwarded the packet.

Currently, no unicast packet is routed by both the device and the
kernel, but this is about to change by subsequent patches and we need to
be able to mark such packets, so that they will no be forwarded twice.

Instead of adding yet another field to 'struct sk_buff', we can just
rename 'offload_mr_fwd_mark' to 'offload_l3_fwd_mark', as a packet
either has a multicast or a unicast destination IP.

While at it, add a comment about both 'offload_fwd_mark' and
'offload_l3_fwd_mark'.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -3554,10 +3554,10 @@ static void mlxsw_sp_rx_listener_mark_func(struct sk_buff *skb, u8 local_port,
 	return mlxsw_sp_rx_listener_no_mark_func(skb, local_port, priv);
 }
 
-static void mlxsw_sp_rx_listener_mr_mark_func(struct sk_buff *skb,
+static void mlxsw_sp_rx_listener_l3_mark_func(struct sk_buff *skb,
 					      u8 local_port, void *priv)
 {
-	skb->offload_mr_fwd_mark = 1;
+	skb->offload_l3_fwd_mark = 1;
 	skb->offload_fwd_mark = 1;
 	return mlxsw_sp_rx_listener_no_mark_func(skb, local_port, priv);
 }
@@ -3605,8 +3605,8 @@ static void mlxsw_sp_rx_listener_sample_func(struct sk_buff *skb, u8 local_port,
 	MLXSW_RXL(mlxsw_sp_rx_listener_mark_func, _trap_id, _action,	\
 		_is_ctrl, SP_##_trap_group, DISCARD)
 
-#define MLXSW_SP_RXL_MR_MARK(_trap_id, _action, _trap_group, _is_ctrl)	\
-	MLXSW_RXL(mlxsw_sp_rx_listener_mr_mark_func, _trap_id, _action,	\
+#define MLXSW_SP_RXL_L3_MARK(_trap_id, _action, _trap_group, _is_ctrl)	\
+	MLXSW_RXL(mlxsw_sp_rx_listener_l3_mark_func, _trap_id, _action,	\
 		_is_ctrl, SP_##_trap_group, DISCARD)
 
 #define MLXSW_SP_EVENTL(_func, _trap_id)		\
@@ -3683,7 +3683,7 @@ static const struct mlxsw_listener mlxsw_sp_listener[] = {
 	MLXSW_SP_RXL_MARK(IPV6_PIM, TRAP_TO_CPU, PIM, false),
 	MLXSW_SP_RXL_MARK(RPF, TRAP_TO_CPU, RPF, false),
 	MLXSW_SP_RXL_MARK(ACL1, TRAP_TO_CPU, MULTICAST, false),
-	MLXSW_SP_RXL_MR_MARK(ACL2, TRAP_TO_CPU, MULTICAST, false),
+	MLXSW_SP_RXL_L3_MARK(ACL2, TRAP_TO_CPU, MULTICAST, false),
 	/* NVE traps */
 	MLXSW_SP_RXL_MARK(NVE_ENCAP_ARP, TRAP_TO_CPU, ARP, false),
 };

include/linux/skbuff.h

@@ -616,6 +616,8 @@ typedef unsigned char *sk_buff_data_t;
  *	@pkt_type: Packet class
  *	@fclone: skbuff clone status
  *	@ipvs_property: skbuff is owned by ipvs
+ *	@offload_fwd_mark: Packet was L2-forwarded in hardware
+ *	@offload_l3_fwd_mark: Packet was L3-forwarded in hardware
  *	@tc_skip_classify: do not classify packet. set by IFB device
  *	@tc_at_ingress: used within tc_classify to distinguish in/egress
  *	@tc_redirected: packet was redirected by a tc action
@@ -799,7 +801,7 @@ struct sk_buff {
 	__u8			remcsum_offload:1;
 #ifdef CONFIG_NET_SWITCHDEV
 	__u8			offload_fwd_mark:1;
-	__u8			offload_mr_fwd_mark:1;
+	__u8			offload_l3_fwd_mark:1;
 #endif
 #ifdef CONFIG_NET_CLS_ACT
 	__u8			tc_skip_classify:1;

net/core/skbuff.c

@@ -4885,7 +4885,7 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet)
 
 #ifdef CONFIG_NET_SWITCHDEV
 	skb->offload_fwd_mark = 0;
-	skb->offload_mr_fwd_mark = 0;
+	skb->offload_l3_fwd_mark = 0;
 #endif
 
 	if (!xnet)

net/ipv4/ipmr.c

@@ -1802,7 +1802,7 @@ static bool ipmr_forward_offloaded(struct sk_buff *skb, struct mr_table *mrt,
 	struct vif_device *out_vif = &mrt->vif_table[out_vifi];
 	struct vif_device *in_vif = &mrt->vif_table[in_vifi];
 
-	if (!skb->offload_mr_fwd_mark)
+	if (!skb->offload_l3_fwd_mark)
 		return false;
 	if (!out_vif->dev_parent_id.id_len || !in_vif->dev_parent_id.id_len)
 		return false;