Re: [RFC PATCH net-next 3/4] rocker: add fwd_mark support

From: Scott Feldman <redacted>

If device flags ingress packet as "fwd offload", mark the skb->fwd_mark
using the ingress port's dev->fwd_mark.  This will be the hint to the
kernel that this packet has already been forwarded by device to egress
ports matching skb->fwd_mark.

For rocker, derive port dev->fwd_mark based on device switch ID.  If port
is bridged, include the bridge's ifindex in the key for deriving
dev->fwd_mark.

Signed-off-by: Scott Feldman <redacted>
---
drivers/net/ethernet/rocker/rocker.c |   24 ++++++++++++++++++++++++
drivers/net/ethernet/rocker/rocker.h |    1 +
2 files changed, 25 insertions(+)

diff --git a/drivers/net/ethernet/rocker/rocker.c b/drivers/net/ethernet/rocker/rocker.c
index a06b93d..81407d8 100644
--- a/drivers/net/ethernet/rocker/rocker.c
+++ b/drivers/net/ethernet/rocker/rocker.c

@@ -4701,6 +4701,7 @@ static int rocker_port_rx_proc(const struct rocker *rocker,

	const struct rocker_tlv *attrs[ROCKER_TLV_RX_MAX + 1];
	struct sk_buff *skb = rocker_desc_cookie_ptr_get(desc_info);
	size_t rx_len;
+	u16 rx_flags = 0;

	if (!skb)
		return -ENOENT;

@@ -4708,6 +4709,8 @@ static int rocker_port_rx_proc(const struct rocker *rocker,

	rocker_tlv_parse_desc(attrs, ROCKER_TLV_RX_MAX, desc_info);
	if (!attrs[ROCKER_TLV_RX_FRAG_LEN])
		return -EINVAL;
+	if (attrs[ROCKER_TLV_RX_FLAGS])
+		rx_flags = rocker_tlv_get_u16(attrs[ROCKER_TLV_RX_FLAGS]);

	rocker_dma_rx_ring_skb_unmap(rocker, attrs);

@@ -4715,6 +4718,9 @@ static int rocker_port_rx_proc(const struct rocker *rocker,

	skb_put(skb, rx_len);
	skb->protocol = eth_type_trans(skb, rocker_port->dev);

+	if (rx_flags & ROCKER_RX_FLAGS_FWD_OFFLOAD)

+		skb->fwd_mark = rocker_port->dev->fwd_mark;
+
	rocker_port->dev->stats.rx_packets++;
	rocker_port->dev->stats.rx_bytes += skb->len;

@@ -4814,6 +4820,21 @@ static void rocker_port_dev_addr_init(struct rocker_port *rocker_port)

	}
}

+static void rocker_port_fwd_mark_set(struct rocker_port *rocker_port)
+{
+	struct rocker *rocker = rocker_port->rocker;
+	struct {
+		u64 hw_id;
+		int ifindex;
+	} key = {
+		.hw_id = rocker->hw.id,
+		.ifindex = rocker_port_is_bridged(rocker_port) ?
+			   rocker_port->bridge_dev->ifindex : 0,
+	};
+
+	rocker_port->dev->fwd_mark = switchdev_mark_get(&key, sizeof(key));
+}
+
static int rocker_probe_port(struct rocker *rocker, unsigned int port_number)
{
	const struct pci_dev *pdev = rocker->pdev;

@@ -4832,6 +4853,7 @@ static int rocker_probe_port(struct rocker *rocker, unsigned int port_number)

	rocker_port->pport = port_number + 1;
	rocker_port->brport_flags = BR_LEARNING | BR_LEARNING_SYNC;
	INIT_LIST_HEAD(&rocker_port->trans_mem);
+	rocker_port_fwd_mark_set(rocker_port);

	rocker_port_dev_addr_init(rocker_port);
	dev->netdev_ops = &rocker_port_netdev_ops;

@@ -5131,6 +5153,7 @@ static int rocker_port_bridge_join(struct rocker_port *rocker_port,

		rocker_port_internal_vlan_id_get(rocker_port, bridge->ifindex);

	rocker_port->bridge_dev = bridge;
+	rocker_port_fwd_mark_set(rocker_port);

	return rocker_port_vlan_add(rocker_port, SWITCHDEV_TRANS_NONE,
				    untagged_vid, 0);

@@ -5152,6 +5175,7 @@ static int rocker_port_bridge_leave(struct rocker_port *rocker_port)

						 rocker_port->dev->ifindex);

	rocker_port->bridge_dev = NULL;
+	rocker_port_fwd_mark_set(rocker_port);