3 files changed, 85 insertions, 60 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index 6b14bd1c60a0..c994a916a58a 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -100,7 +100,12 @@ struct ipoib_pseudoheader {
 
 struct ipoib_mcast;
 
-struct ipoib_buf {
+struct ipoib_rx_buf {
+        struct sk_buff *skb;
+        dma_addr_t      mapping;
+};
+
+struct ipoib_tx_buf {
         struct sk_buff *skb;
         DECLARE_PCI_UNMAP_ADDR(mapping)
 };
@@ -150,14 +155,14 @@ struct ipoib_dev_priv {
         unsigned int admin_mtu;
         unsigned int mcast_mtu;
 
-        struct ipoib_buf *rx_ring;
+        struct ipoib_rx_buf *rx_ring;
 
-        spinlock_t        tx_lock;
-        struct ipoib_buf *tx_ring;
-        unsigned          tx_head;
-        unsigned          tx_tail;
-        struct ib_sge     tx_sge;
-        struct ib_send_wr tx_wr;
+        spinlock_t           tx_lock;
+        struct ipoib_tx_buf *tx_ring;
+        unsigned             tx_head;
+        unsigned             tx_tail;
+        struct ib_sge        tx_sge;
+        struct ib_send_wr    tx_wr;
 
         struct ib_wc ibwc[IPOIB_NUM_WC];
 
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index 02d0e0006578..192fef884e21 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -95,57 +95,65 @@ void ipoib_free_ah(struct kref *kref)
         }
 }
 
-static inline int ipoib_ib_receive(struct ipoib_dev_priv *priv,
-                                   unsigned int wr_id,
-                                   dma_addr_t addr)
+static int ipoib_ib_post_receive(struct net_device *dev, int id)
 {
-        struct ib_sge list = {
-                .addr    = addr,
-                .length  = IPOIB_BUF_SIZE,
-                .lkey    = priv->mr->lkey,
-        };
-        struct ib_recv_wr param = {
-                .wr_id      = wr_id | IPOIB_OP_RECV,
-                .sg_list    = &list,
-                .num_sge    = 1,
-        };
+        struct ipoib_dev_priv *priv = netdev_priv(dev);
+        struct ib_sge list;
+        struct ib_recv_wr param;
         struct ib_recv_wr *bad_wr;
+        int ret;
+
+        list.addr     = priv->rx_ring[id].mapping;
+        list.length   = IPOIB_BUF_SIZE;
+        list.lkey     = priv->mr->lkey;
+
+        param.next    = NULL;
+        param.wr_id   = id | IPOIB_OP_RECV;
+        param.sg_list = &list;
+        param.num_sge = 1;
+
+        ret = ib_post_recv(priv->qp, &param, &bad_wr);
+        if (unlikely(ret)) {
+                ipoib_warn(priv, "receive failed for buf %d (%d)\n", id, ret);
+                dma_unmap_single(priv->ca->dma_device,
+                                 priv->rx_ring[id].mapping,
+                                 IPOIB_BUF_SIZE, DMA_FROM_DEVICE);
+                dev_kfree_skb_any(priv->rx_ring[id].skb);
+                priv->rx_ring[id].skb = NULL;
+        }
 
-        return ib_post_recv(priv->qp, &param, &bad_wr);
+        return ret;
 }
 
-static int ipoib_ib_post_receive(struct net_device *dev, int id)
+static int ipoib_alloc_rx_skb(struct net_device *dev, int id)
 {
         struct ipoib_dev_priv *priv = netdev_priv(dev);
         struct sk_buff *skb;
         dma_addr_t addr;
-        int ret;
 
         skb = dev_alloc_skb(IPOIB_BUF_SIZE + 4);
-        if (!skb) {
-                ipoib_warn(priv, "failed to allocate receive buffer\n");
-
-                priv->rx_ring[id].skb = NULL;
+        if (!skb)
                 return -ENOMEM;
-        }
-        skb_reserve(skb, 4);    /* 16 byte align IP header */
-        priv->rx_ring[id].skb = skb;
+
+        /*
+         * IB will leave a 40 byte gap for a GRH and IPoIB adds a 4 byte
+         * header.  So we need 4 more bytes to get to 48 and align the
+         * IP header to a multiple of 16.
+         */
+        skb_reserve(skb, 4);
+
         addr = dma_map_single(priv->ca->dma_device,
                               skb->data, IPOIB_BUF_SIZE,
                               DMA_FROM_DEVICE);
-        pci_unmap_addr_set(&priv->rx_ring[id], mapping, addr);
-
-        ret = ipoib_ib_receive(priv, id, addr);
-        if (ret) {
-                ipoib_warn(priv, "ipoib_ib_receive failed for buf %d (%d)\n",
-                           id, ret);
-                dma_unmap_single(priv->ca->dma_device, addr,
-                                 IPOIB_BUF_SIZE, DMA_FROM_DEVICE);
+        if (unlikely(dma_mapping_error(addr))) {
                 dev_kfree_skb_any(skb);
-                priv->rx_ring[id].skb = NULL;
+                return -EIO;
         }
 
-        return ret;
+        priv->rx_ring[id].skb     = skb;
+        priv->rx_ring[id].mapping = addr;
+
+        return 0;
 }
 
 static int ipoib_ib_post_receives(struct net_device *dev)
@@ -154,6 +162,10 @@ static int ipoib_ib_post_receives(struct net_device *dev)
         int i;
 
         for (i = 0; i < IPOIB_RX_RING_SIZE; ++i) {
+                if (ipoib_alloc_rx_skb(dev, i)) {
+                        ipoib_warn(priv, "failed to allocate receive buffer %d\n", i);
+                        return -ENOMEM;
+                }
                 if (ipoib_ib_post_receive(dev, i)) {
                         ipoib_warn(priv, "ipoib_ib_post_receive failed for buf %d\n", i);
                         return -EIO;
@@ -176,28 +188,36 @@ static void ipoib_ib_handle_wc(struct net_device *dev,
                 wr_id &= ~IPOIB_OP_RECV;
 
                 if (wr_id < IPOIB_RX_RING_SIZE) {
-                        struct sk_buff *skb = priv->rx_ring[wr_id].skb;
-
-                        priv->rx_ring[wr_id].skb = NULL;
+                        struct sk_buff *skb  = priv->rx_ring[wr_id].skb;
+                        dma_addr_t      addr = priv->rx_ring[wr_id].mapping;
 
-                        dma_unmap_single(priv->ca->dma_device,
-                                         pci_unmap_addr(&priv->rx_ring[wr_id],
-                                                        mapping),
-                                         IPOIB_BUF_SIZE,
-                                         DMA_FROM_DEVICE);
-
-                        if (wc->status != IB_WC_SUCCESS) {
+                        if (unlikely(wc->status != IB_WC_SUCCESS)) {
                                 if (wc->status != IB_WC_WR_FLUSH_ERR)
                                         ipoib_warn(priv, "failed recv event "
                                                    "(status=%d, wrid=%d vend_err %x)\n",
                                                    wc->status, wr_id, wc->vendor_err);
+                                dma_unmap_single(priv->ca->dma_device, addr,
+                                                 IPOIB_BUF_SIZE, DMA_FROM_DEVICE);
                                 dev_kfree_skb_any(skb);
+                                priv->rx_ring[wr_id].skb = NULL;
                                 return;
                         }
 
+                        /*
+                         * If we can't allocate a new RX buffer, dump
+                         * this packet and reuse the old buffer.
+                         */
+                        if (unlikely(ipoib_alloc_rx_skb(dev, wr_id))) {
+                                ++priv->stats.rx_dropped;
+                                goto repost;
+                        }
+
                         ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
                                        wc->byte_len, wc->slid);
 
+                        dma_unmap_single(priv->ca->dma_device, addr,
+                                         IPOIB_BUF_SIZE, DMA_FROM_DEVICE);
+
                         skb_put(skb, wc->byte_len);
                         skb_pull(skb, IB_GRH_BYTES);
 
@@ -220,8 +240,8 @@ static void ipoib_ib_handle_wc(struct net_device *dev,
                                 dev_kfree_skb_any(skb);
                         }
 
-                        /* repost receive */
-                        if (ipoib_ib_post_receive(dev, wr_id))
+                repost:
+                        if (unlikely(ipoib_ib_post_receive(dev, wr_id)))
                                 ipoib_warn(priv, "ipoib_ib_post_receive failed "
                                            "for buf %d\n", wr_id);
                 } else
@@ -229,7 +249,7 @@ static void ipoib_ib_handle_wc(struct net_device *dev,
                                    wr_id);
 
         } else {
-                struct ipoib_buf *tx_req;
+                struct ipoib_tx_buf *tx_req;
                 unsigned long flags;
 
                 if (wr_id >= IPOIB_TX_RING_SIZE) {
@@ -302,7 +322,7 @@ void ipoib_send(struct net_device *dev, struct sk_buff *skb,
                 struct ipoib_ah *address, u32 qpn)
 {
         struct ipoib_dev_priv *priv = netdev_priv(dev);
-        struct ipoib_buf *tx_req;
+        struct ipoib_tx_buf *tx_req;
         dma_addr_t addr;
 
         if (skb->len > dev->mtu + INFINIBAND_ALEN) {
@@ -468,7 +488,7 @@ int ipoib_ib_dev_stop(struct net_device *dev)
         struct ib_qp_attr qp_attr;
         int attr_mask;
         unsigned long begin;
-        struct ipoib_buf *tx_req;
+        struct ipoib_tx_buf *tx_req;
         int i;
 
         /* Kill the existing QP and allocate a new one */
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index ee303859b044..cd4f42328dbe 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -732,7 +732,7 @@ int ipoib_dev_init(struct net_device *dev, struct ib_device *ca, int port)
 
         /* Allocate RX/TX "rings" to hold queued skbs */
 
-        priv->rx_ring = kmalloc(IPOIB_RX_RING_SIZE * sizeof (struct ipoib_buf),
+        priv->rx_ring = kmalloc(IPOIB_RX_RING_SIZE * sizeof (struct ipoib_rx_buf),
                                 GFP_KERNEL);
         if (!priv->rx_ring) {
                 printk(KERN_WARNING "%s: failed to allocate RX ring (%d entries)\n",
@@ -740,9 +740,9 @@ int ipoib_dev_init(struct net_device *dev, struct ib_device *ca, int port)
                 goto out;
         }
         memset(priv->rx_ring, 0,
-               IPOIB_RX_RING_SIZE * sizeof (struct ipoib_buf));
+               IPOIB_RX_RING_SIZE * sizeof (struct ipoib_rx_buf));
 
-        priv->tx_ring = kmalloc(IPOIB_TX_RING_SIZE * sizeof (struct ipoib_buf),
+        priv->tx_ring = kmalloc(IPOIB_TX_RING_SIZE * sizeof (struct ipoib_tx_buf),
                                 GFP_KERNEL);
         if (!priv->tx_ring) {
                 printk(KERN_WARNING "%s: failed to allocate TX ring (%d entries)\n",
@@ -750,7 +750,7 @@ int ipoib_dev_init(struct net_device *dev, struct ib_device *ca, int port)
                 goto out_rx_ring_cleanup;
         }
         memset(priv->tx_ring, 0,
-               IPOIB_TX_RING_SIZE * sizeof (struct ipoib_buf));
+               IPOIB_TX_RING_SIZE * sizeof (struct ipoib_tx_buf));
 
         /* priv->tx_head & tx_tail are already 0 */