IPoIB: Refactor completion handling

Split up ipoib_ib_handle_wc() into ipoib_ib_handle_rx_wc() and
ipoib_ib_handle_tx_wc() to make the code easier to read.  This will
also help implement NAPI in the future.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 100 insertions, 88 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
index 5033666b1481..722177ea069b 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c
@@ -169,117 +169,129 @@ static int ipoib_ib_post_receives(struct net_device *dev)
         return 0;
 }
 
-static void ipoib_ib_handle_wc(struct net_device *dev,
-                               struct ib_wc *wc)
+static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
 {
         struct ipoib_dev_priv *priv = netdev_priv(dev);
-        unsigned int wr_id = wc->wr_id;
+        unsigned int wr_id = wc->wr_id & ~IPOIB_OP_RECV;
+        struct sk_buff *skb;
+        dma_addr_t addr;
 
-        ipoib_dbg_data(priv, "called: id %d, op %d, status: %d\n",
+        ipoib_dbg_data(priv, "recv completion: id %d, op %d, status: %d\n",
                        wr_id, wc->opcode, wc->status);
 
-        if (wr_id & IPOIB_OP_RECV) {
-                wr_id &= ~IPOIB_OP_RECV;
-
-                if (wr_id < ipoib_recvq_size) {
-                        struct sk_buff *skb  = priv->rx_ring[wr_id].skb;
-                        dma_addr_t      addr = priv->rx_ring[wr_id].mapping;
-
-                        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 (unlikely(wr_id >= ipoib_recvq_size)) {
+                ipoib_warn(priv, "recv completion event with wrid %d (> %d)\n",
+                           wr_id, ipoib_recvq_size);
+                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;
-                        }
+        skb  = priv->rx_ring[wr_id].skb;
+        addr = priv->rx_ring[wr_id].mapping;
 
-                        ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
-                                       wc->byte_len, wc->slid);
+        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;
+        }
 
-                        dma_unmap_single(priv->ca->dma_device, addr,
-                                         IPOIB_BUF_SIZE, DMA_FROM_DEVICE);
+        /*
+         * 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;
+        }
 
-                        skb_put(skb, wc->byte_len);
-                        skb_pull(skb, IB_GRH_BYTES);
+        ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
+                       wc->byte_len, wc->slid);
 
-                        if (wc->slid != priv->local_lid ||
-                            wc->src_qp != priv->qp->qp_num) {
-                                skb->protocol = ((struct ipoib_header *) skb->data)->proto;
-                                skb->mac.raw = skb->data;
-                                skb_pull(skb, IPOIB_ENCAP_LEN);
+        dma_unmap_single(priv->ca->dma_device, addr,
+                         IPOIB_BUF_SIZE, DMA_FROM_DEVICE);
 
-                                dev->last_rx = jiffies;
-                                ++priv->stats.rx_packets;
-                                priv->stats.rx_bytes += skb->len;
+        skb_put(skb, wc->byte_len);
+        skb_pull(skb, IB_GRH_BYTES);
 
-                                skb->dev = dev;
-                                /* XXX get correct PACKET_ type here */
-                                skb->pkt_type = PACKET_HOST;
-                                netif_rx_ni(skb);
-                        } else {
-                                ipoib_dbg_data(priv, "dropping loopback packet\n");
-                                dev_kfree_skb_any(skb);
-                        }
+        if (wc->slid != priv->local_lid ||
+            wc->src_qp != priv->qp->qp_num) {
+                skb->protocol = ((struct ipoib_header *) skb->data)->proto;
+                skb->mac.raw = skb->data;
+                skb_pull(skb, IPOIB_ENCAP_LEN);
 
-                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
-                        ipoib_warn(priv, "completion event with wrid %d\n",
-                                   wr_id);
+                dev->last_rx = jiffies;
+                ++priv->stats.rx_packets;
+                priv->stats.rx_bytes += skb->len;
 
+                skb->dev = dev;
+                /* XXX get correct PACKET_ type here */
+                skb->pkt_type = PACKET_HOST;
+                netif_rx_ni(skb);
         } else {
-                struct ipoib_tx_buf *tx_req;
-                unsigned long flags;
+                ipoib_dbg_data(priv, "dropping loopback packet\n");
+                dev_kfree_skb_any(skb);
+        }
 
-                if (wr_id >= ipoib_sendq_size) {
-                        ipoib_warn(priv, "completion event with wrid %d (> %d)\n",
-                                   wr_id, ipoib_sendq_size);
-                        return;
-                }
+repost:
+        if (unlikely(ipoib_ib_post_receive(dev, wr_id)))
+                ipoib_warn(priv, "ipoib_ib_post_receive failed "
+                           "for buf %d\n", wr_id);
+}
 
-                ipoib_dbg_data(priv, "send complete, wrid %d\n", wr_id);
+static void ipoib_ib_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
+{
+        struct ipoib_dev_priv *priv = netdev_priv(dev);
+        unsigned int wr_id = wc->wr_id;
+        struct ipoib_tx_buf *tx_req;
+        unsigned long flags;
 
-                tx_req = &priv->tx_ring[wr_id];
+        ipoib_dbg_data(priv, "send completion: id %d, op %d, status: %d\n",
+                       wr_id, wc->opcode, wc->status);
 
-                dma_unmap_single(priv->ca->dma_device,
-                                 pci_unmap_addr(tx_req, mapping),
-                                 tx_req->skb->len,
-                                 DMA_TO_DEVICE);
+        if (unlikely(wr_id >= ipoib_sendq_size)) {
+                ipoib_warn(priv, "send completion event with wrid %d (> %d)\n",
+                           wr_id, ipoib_sendq_size);
+                return;
+        }
 
-                ++priv->stats.tx_packets;
-                priv->stats.tx_bytes += tx_req->skb->len;
+        tx_req = &priv->tx_ring[wr_id];
 
-                dev_kfree_skb_any(tx_req->skb);
+        dma_unmap_single(priv->ca->dma_device,
+                         pci_unmap_addr(tx_req, mapping),
+                         tx_req->skb->len,
+                         DMA_TO_DEVICE);
 
-                spin_lock_irqsave(&priv->tx_lock, flags);
-                ++priv->tx_tail;
-                if (netif_queue_stopped(dev) &&
-                    test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags) &&
-                    priv->tx_head - priv->tx_tail <= ipoib_sendq_size >> 1)
-                        netif_wake_queue(dev);
-                spin_unlock_irqrestore(&priv->tx_lock, flags);
+        ++priv->stats.tx_packets;
+        priv->stats.tx_bytes += tx_req->skb->len;
 
-                if (wc->status != IB_WC_SUCCESS &&
-                    wc->status != IB_WC_WR_FLUSH_ERR)
-                        ipoib_warn(priv, "failed send event "
-                                   "(status=%d, wrid=%d vend_err %x)\n",
-                                   wc->status, wr_id, wc->vendor_err);
-        }
+        dev_kfree_skb_any(tx_req->skb);
+
+        spin_lock_irqsave(&priv->tx_lock, flags);
+        ++priv->tx_tail;
+        if (netif_queue_stopped(dev) &&
+            test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags) &&
+            priv->tx_head - priv->tx_tail <= ipoib_sendq_size >> 1)
+                netif_wake_queue(dev);
+        spin_unlock_irqrestore(&priv->tx_lock, flags);
+
+        if (wc->status != IB_WC_SUCCESS &&
+            wc->status != IB_WC_WR_FLUSH_ERR)
+                ipoib_warn(priv, "failed send event "
+                           "(status=%d, wrid=%d vend_err %x)\n",
+                           wc->status, wr_id, wc->vendor_err);
+}
+
+static void ipoib_ib_handle_wc(struct net_device *dev, struct ib_wc *wc)
+{
+        if (wc->wr_id & IPOIB_OP_RECV)
+                ipoib_ib_handle_rx_wc(dev, wc);
+        else
+                ipoib_ib_handle_tx_wc(dev, wc);
 }
 
 void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr)