[PATCH net-next v6 5/5] amd-xgbe: add ethtool jumbo frame selftest

[Raju Rangoju <Raju.Rangoju@amd.com>]

Adds support for jumbo frame selftest. Works only for
mtu size greater than 1500.

Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
---
Changes since v4:
 - remove double semicolon

 drivers/net/ethernet/amd/xgbe/xgbe-selftest.c | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-selftest.c b/drivers/net/ethernet/amd/xgbe/xgbe-selftest.c
index 15c51e96bcdf..55e5e467facd 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-selftest.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-selftest.c
@@ -42,11 +42,19 @@ static int xgbe_test_loopback_validate(struct sk_buff *skb,
 	struct tcphdr *th;
 	struct udphdr *uh;
 	struct iphdr *ih;
+	int eat;
 
 	skb = skb_unshare(skb, GFP_ATOMIC);
 	if (!skb)
 		goto out;
 
+	eat = (skb->tail + skb->data_len) - skb->end;
+	if (eat > 0 && skb_shared(skb)) {
+		skb = skb_share_check(skb, GFP_ATOMIC);
+		if (!skb)
+			goto out;
+	}
+
 	if (skb_linearize(skb))
 		goto out;
 
@@ -215,6 +223,17 @@ static int xgbe_test_sph(struct xgbe_prv_data *pdata)
 	return 0;
 }
 
+static int xgbe_test_jumbo(struct xgbe_prv_data *pdata)
+{
+	struct net_packet_attrs attr = {};
+	int size = pdata->rx_buf_size;
+
+	attr.dst = pdata->netdev->dev_addr;
+	attr.max_size = size - ETH_FCS_LEN;
+
+	return __xgbe_test_loopback(pdata, &attr);
+}
+
 static const struct xgbe_test xgbe_selftests[] = {
 	{
 		.name = "MAC Loopback   ",
@@ -228,6 +247,10 @@ static const struct xgbe_test xgbe_selftests[] = {
 		.name = "Split Header   ",
 		.lb = XGBE_LOOPBACK_PHY,
 		.fn = xgbe_test_sph,
+	}, {
+		.name = "Jumbo Frame    ",
+		.lb = XGBE_LOOPBACK_PHY,
+		.fn = xgbe_test_jumbo,
 	},
 };
 
-- 
2.34.1