IPoIB: Add LSO support

For HCAs that support TCP segmentation offload (IB_DEVICE_UD_TSO), set
NETIF_F_TSO and use HW LSO to offload TCP segmentation.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index 08930ca..19a41ff 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -319,6 +319,7 @@ struct ipoib_dev_priv {
        struct dentry *mcg_dentry;
        struct dentry *path_dentry;
 #endif
+       int     hca_caps;
 };
 
 struct ipoib_ah {

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_cm.c b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
index edf63dc..9d411f2 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_cm.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_cm.c
@@ -1384,7 +1384,7 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
                ipoib_warn(priv, "enabling connected mode "
                           "will cause multicast packet drops\n");
 
-               dev->features &= ~(NETIF_F_IP_CSUM | NETIF_F_SG);
+               dev->features &= ~(NETIF_F_IP_CSUM | NETIF_F_SG | NETIF_F_TSO);
                priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
 
                ipoib_flush_paths(dev);
@@ -1396,8 +1396,11 @@ static ssize_t set_mode(struct device *d, struct device_attribute *attr,
                dev->mtu = min(priv->mcast_mtu, dev->mtu);
                ipoib_flush_paths(dev);
 
-               if (test_bit(IPOIB_FLAG_CSUM, &priv->flags))
+               if (test_bit(IPOIB_FLAG_CSUM, &priv->flags)) {
                        dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
+                       if (priv->hca_caps & IB_DEVICE_UD_TSO)
+                               dev->features |= NETIF_F_TSO;
+               }
 
                return count;
        }

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index d13f4fb..8b4ff69 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -39,6 +39,8 @@
 #include <linux/dma-mapping.h>
 
 #include <rdma/ib_cache.h>
+#include <linux/ip.h>
+#include <linux/tcp.h>
 
 #include "ipoib.h"
 
@@ -249,29 +251,37 @@ static int ipoib_dma_map_tx(struct ib_device *ca,
        struct sk_buff *skb = tx_req->skb;
        u64 *mapping = tx_req->mapping;
        int i;
+       int off;
 
-       mapping[0] = ib_dma_map_single(ca, skb->data, skb_headlen(skb),
-                                      DMA_TO_DEVICE);
-       if (unlikely(ib_dma_mapping_error(ca, mapping[0])))
-               return -EIO;
+       if (skb_headlen(skb)) {
+               mapping[0] = ib_dma_map_single(ca, skb->data, skb_headlen(skb),
+                                              DMA_TO_DEVICE);
+               if (unlikely(ib_dma_mapping_error(ca, mapping[0])))
+                       return -EIO;
+
+               off = 1;
+       } else
+               off = 0;
 
        for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-               mapping[i + 1] = ib_dma_map_page(ca, frag->page,
+               mapping[i + off] = ib_dma_map_page(ca, frag->page,
                                                 frag->page_offset, frag->size,
                                                 DMA_TO_DEVICE);
-               if (unlikely(ib_dma_mapping_error(ca, mapping[i + 1])))
+               if (unlikely(ib_dma_mapping_error(ca, mapping[i + off])))
                        goto partial_error;
        }
        return 0;
 
 partial_error:
-       ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
-
        for (; i > 0; --i) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
-               ib_dma_unmap_page(ca, mapping[i], frag->size, DMA_TO_DEVICE);
+               ib_dma_unmap_page(ca, mapping[i - !off], frag->size, DMA_TO_DEVICE);
        }
+
+       if (off)
+               ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
+
        return -EIO;
 }
 
@@ -281,12 +291,17 @@ static void ipoib_dma_unmap_tx(struct ib_device *ca,
        struct sk_buff *skb = tx_req->skb;
        u64 *mapping = tx_req->mapping;
        int i;
+       int off;
 
-       ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
+       if (skb_headlen(skb)) {
+               ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
+               off = 1;
+       } else
+               off = 0;
 
        for (i = 0; i < skb_shinfo(skb)->nr_frags; ++i) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
-               ib_dma_unmap_page(ca, mapping[i + 1], frag->size,
+               ib_dma_unmap_page(ca, mapping[i + off], frag->size,
                                  DMA_TO_DEVICE);
        }
 }
@@ -392,24 +407,40 @@ void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr)
 static inline int post_send(struct ipoib_dev_priv *priv,
                            unsigned int wr_id,
                            struct ib_ah *address, u32 qpn,
-                           u64 *mapping, int headlen,
-                           skb_frag_t *frags,
-                           int nr_frags)
+                           struct ipoib_tx_buf *tx_req,
+                           void *head, int hlen)
 {
        struct ib_send_wr *bad_wr;
-       int i;
+       int i, off;
+       struct sk_buff *skb = tx_req->skb;
+       skb_frag_t *frags = skb_shinfo(skb)->frags;
+       int nr_frags = skb_shinfo(skb)->nr_frags;
+       u64 *mapping = tx_req->mapping;
+
+       if (skb_headlen(skb)) {
+               priv->tx_sge[0].addr         = mapping[0];
+               priv->tx_sge[0].length       = skb_headlen(skb);
+               off = 1;
+       } else
+               off = 0;
 
-       priv->tx_sge[0].addr         = mapping[0];
-       priv->tx_sge[0].length       = headlen;
        for (i = 0; i < nr_frags; ++i) {
-               priv->tx_sge[i + 1].addr = mapping[i + 1];
-               priv->tx_sge[i + 1].length = frags[i].size;
+               priv->tx_sge[i + off].addr = mapping[i + off];
+               priv->tx_sge[i + off].length = frags[i].size;
        }
-       priv->tx_wr.num_sge          = nr_frags + 1;
+       priv->tx_wr.num_sge          = nr_frags + off;
        priv->tx_wr.wr_id            = wr_id;
        priv->tx_wr.wr.ud.remote_qpn = qpn;
        priv->tx_wr.wr.ud.ah         = address;
 
+       if (head) {
+               priv->tx_wr.wr.ud.mss    = skb_shinfo(skb)->gso_size;
+               priv->tx_wr.wr.ud.header = head;
+               priv->tx_wr.wr.ud.hlen   = hlen;
+               priv->tx_wr.opcode       = IB_WR_LSO;
+       } else
+               priv->tx_wr.opcode       = IB_WR_SEND;
+
        return ib_post_send(priv->qp, &priv->tx_wr, &bad_wr);
 }
 
@@ -418,14 +449,30 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb,
 {
        struct ipoib_dev_priv *priv = netdev_priv(dev);
        struct ipoib_tx_buf *tx_req;
-
-       if (unlikely(skb->len > priv->mcast_mtu + IPOIB_ENCAP_LEN)) {
-               ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n",
-                          skb->len, priv->mcast_mtu + IPOIB_ENCAP_LEN);
-               ++dev->stats.tx_dropped;
-               ++dev->stats.tx_errors;
-               ipoib_cm_skb_too_long(dev, skb, priv->mcast_mtu);
-               return;
+       int hlen;
+       void *phead;
+
+       if (skb_is_gso(skb)) {
+               hlen = skb_transport_offset(skb) + tcp_hdrlen(skb);
+               phead = skb->data;
+               if (unlikely(!skb_pull(skb, hlen))) {
+                       ipoib_warn(priv, "linear data too small\n");
+                       ++dev->stats.tx_dropped;
+                       ++dev->stats.tx_errors;
+                       dev_kfree_skb_any(skb);
+                       return;
+               }
+       } else {
+               if (unlikely(skb->len > priv->mcast_mtu + IPOIB_ENCAP_LEN)) {
+                       ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n",
+                                  skb->len, priv->mcast_mtu + IPOIB_ENCAP_LEN);
+                       ++dev->stats.tx_dropped;
+                       ++dev->stats.tx_errors;
+                       ipoib_cm_skb_too_long(dev, skb, priv->mcast_mtu);
+                       return;
+               }
+               phead = NULL;
+               hlen  = 0;
        }
 
        ipoib_dbg_data(priv, "sending packet, length=%d address=%p qpn=0x%06x\n",
@@ -452,9 +499,7 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb,
                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),
-                              skb_shinfo(skb)->frags, skb_shinfo(skb)->nr_frags))) {
+                              address->ah, qpn, tx_req, phead, hlen))) {
                ipoib_warn(priv, "post_send failed\n");
                ++dev->stats.tx_errors;
                ipoib_dma_unmap_tx(priv->ca, tx_req);

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index d87f531..35a3643 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1134,14 +1134,15 @@ static struct net_device *ipoib_add_port(const char *format,
                kfree(device_attr);
                goto device_init_failed;
        }
+       priv->hca_caps = device_attr->device_cap_flags;
 
-       if (device_attr->device_cap_flags & IB_DEVICE_UD_IP_CSUM) {
+       kfree(device_attr);
+
+       if (priv->hca_caps & IB_DEVICE_UD_IP_CSUM) {
                set_bit(IPOIB_FLAG_CSUM, &priv->flags);
                priv->dev->features |= NETIF_F_SG | NETIF_F_IP_CSUM;
        }
 
-       kfree(device_attr);
-
        /*
         * Set the full membership bit, so that we join the right
         * broadcast group, etc.
@@ -1176,6 +1177,9 @@ static struct net_device *ipoib_add_port(const char *format,
                goto event_failed;
        }
 
+       if (priv->dev->features & NETIF_F_SG && priv->hca_caps & IB_DEVICE_UD_TSO)
+               priv->dev->features |= NETIF_F_TSO;
+
        result = register_netdev(priv->dev);
        if (result) {
                printk(KERN_WARNING "%s: couldn't register ipoib port %d; error %d\n",

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
index a3aeb91..8a20e37 100644 (file)
--- a/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_verbs.c
@@ -192,6 +192,9 @@ int ipoib_transport_dev_init(struct net_device *dev, struct ib_device *ca)
        init_attr.send_cq = priv->cq;
        init_attr.recv_cq = priv->cq;
 
+       if (priv->hca_caps & IB_DEVICE_UD_TSO)
+               init_attr.create_flags = IB_QP_CREATE_IPOIB_UD_LSO;
+
        if (dev->features & NETIF_F_SG)
                init_attr.cap.max_send_sge = MAX_SKB_FRAGS + 1;