[ofa-general] [PATCH 4/16 v2] IB/ipoib: Add checksum offload support for ipoib

[Eli Cohen]

Add checksum offload support for ipoib

Signed-off-by: Eli Cohen <eli at mellanox.co.il>
---

changes:
remove ipv6 support
add call to skb_reset_network_header()

 drivers/infiniband/ulp/ipoib/ipoib.h      |    1 +
 drivers/infiniband/ulp/ipoib/ipoib_cm.c   |    9 +++++++++
 drivers/infiniband/ulp/ipoib/ipoib_ib.c   |   20 ++++++++++++++++++++
 drivers/infiniband/ulp/ipoib/ipoib_main.c |   15 +++++++++++++++
 4 files changed, 45 insertions(+), 0 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index 6729c14..f0876dc 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -86,6 +86,7 @@ enum {
 	IPOIB_MCAST_STARTED       = 8,
 	IPOIB_FLAG_ADMIN_CM 	  = 9,
 	IPOIB_FLAG_UMCAST	  = 10,
+	IPOIB_FLAG_CSUM		  = 11,
 
 	IPOIB_MAX_BACKOFF_SECONDS = 16,
 
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index 8485fde..1c1e446 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -1234,6 +1234,11 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
 		set_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
 		ipoib_warn(priv, "enabling connected mode "
 			   "will cause multicast packet drops\n");
+
+		dev->features &= ~NETIF_F_IP_CSUM;
+
+		priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
+
 		ipoib_flush_paths(dev);
 		return count;
 	}
@@ -1242,6 +1247,10 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
 		clear_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
 		dev->mtu = min(priv->mcast_mtu, dev->mtu);
 		ipoib_flush_paths(dev);
+
+		if (priv->ca->flags & IB_DEVICE_IP_CSUM)
+			dev->features |= NETIF_F_IP_CSUM;
+
 		return count;
 	}
 
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index 680c27f..875eba0 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -37,6 +37,7 @@
 
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
+#include <linux/ip.h>
 
 #include <rdma/ib_cache.h>
 
@@ -231,6 +232,19 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
 	skb->dev = dev;
 	/* XXX get correct PACKET_ type here */
 	skb->pkt_type = PACKET_HOST;
+
+	/* check rx csum */
+	if (test_bit(IPOIB_FLAG_CSUM, &priv->flags) && likely(wc->csum_ok)) {
+		/*
+		 * Note: this is a specific requirement for Mellanox
+		 * HW but since it is the only HW currently supporting
+		 * checksum offload I put it here
+		 */
+		skb_reset_network_header(skb);
+		if (ip_hdr(skb)->ihl == 5)
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+	}
+
 	netif_receive_skb(skb);
 
 repost:
@@ -394,6 +408,12 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb,
 		return;
 	}
 
+	if (dev->flags & NETIF_F_IP_CSUM &&
+	    skb->ip_summed == CHECKSUM_PARTIAL)
+		priv->tx_wr.send_flags |= IB_SEND_IP_CSUM;
+	else
+		priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
+
 	if (unlikely(post_send(priv, priv->tx_head & (ipoib_sendq_size - 1),
 			       address->ah, qpn,
 			       tx_req->mapping, skb_headlen(skb),
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index b40e0f7..c0e6c01 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1106,6 +1106,20 @@ int ipoib_add_pkey_attr(struct net_device *dev)
 	return device_create_file(&dev->dev, &dev_attr_pkey);
 }
 
+static void set_csum(struct net_device *dev, struct ib_device *hca)
+{
+	struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+	if (test_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags))
+		return;
+
+	if (!(hca->flags & IB_DEVICE_IP_CSUM))
+		return;
+
+	dev->features |= NETIF_F_SG | NETIF_F_IP_CSUM;
+	set_bit(IPOIB_FLAG_CSUM, &priv->flags);
+}
+
 static struct net_device *ipoib_add_port(const char *format,
 					 struct ib_device *hca, u8 port)
 {
@@ -1144,6 +1158,7 @@ static struct net_device *ipoib_add_port(const char *format,
 	} else
 		memcpy(priv->dev->dev_addr + 4, priv->local_gid.raw, sizeof (union ib_gid));
 
+	set_csum(priv->dev, hca);
 
 	result = ipoib_dev_init(priv->dev, hca, port);
 	if (result < 0) {
-- 
1.5.3.8