Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / infiniband / ulp / ipoib / ipoib_ib.c
diff --git a/kernel/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/kernel/drivers/infiniband/ulp/ipoib/ipoib_ib.c
new file mode 100644 (file)
index 0000000..63b92cb
--- /dev/null
@@ -0,0 +1,1123 @@
+/*
+ * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
+ * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2004, 2005 Voltaire, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/delay.h>
+#include <linux/moduleparam.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+
+#include <linux/ip.h>
+#include <linux/tcp.h>
+
+#include "ipoib.h"
+
+#ifdef CONFIG_INFINIBAND_IPOIB_DEBUG_DATA
+static int data_debug_level;
+
+module_param(data_debug_level, int, 0644);
+MODULE_PARM_DESC(data_debug_level,
+                "Enable data path debug tracing if > 0");
+#endif
+
+static DEFINE_MUTEX(pkey_mutex);
+
+struct ipoib_ah *ipoib_create_ah(struct net_device *dev,
+                                struct ib_pd *pd, struct ib_ah_attr *attr)
+{
+       struct ipoib_ah *ah;
+       struct ib_ah *vah;
+
+       ah = kmalloc(sizeof *ah, GFP_KERNEL);
+       if (!ah)
+               return ERR_PTR(-ENOMEM);
+
+       ah->dev       = dev;
+       ah->last_send = 0;
+       kref_init(&ah->ref);
+
+       vah = ib_create_ah(pd, attr);
+       if (IS_ERR(vah)) {
+               kfree(ah);
+               ah = (struct ipoib_ah *)vah;
+       } else {
+               ah->ah = vah;
+               ipoib_dbg(netdev_priv(dev), "Created ah %p\n", ah->ah);
+       }
+
+       return ah;
+}
+
+void ipoib_free_ah(struct kref *kref)
+{
+       struct ipoib_ah *ah = container_of(kref, struct ipoib_ah, ref);
+       struct ipoib_dev_priv *priv = netdev_priv(ah->dev);
+
+       unsigned long flags;
+
+       spin_lock_irqsave(&priv->lock, flags);
+       list_add_tail(&ah->list, &priv->dead_ahs);
+       spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void ipoib_ud_dma_unmap_rx(struct ipoib_dev_priv *priv,
+                                 u64 mapping[IPOIB_UD_RX_SG])
+{
+       ib_dma_unmap_single(priv->ca, mapping[0],
+                           IPOIB_UD_BUF_SIZE(priv->max_ib_mtu),
+                           DMA_FROM_DEVICE);
+}
+
+static int ipoib_ib_post_receive(struct net_device *dev, int id)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       struct ib_recv_wr *bad_wr;
+       int ret;
+
+       priv->rx_wr.wr_id   = id | IPOIB_OP_RECV;
+       priv->rx_sge[0].addr = priv->rx_ring[id].mapping[0];
+       priv->rx_sge[1].addr = priv->rx_ring[id].mapping[1];
+
+
+       ret = ib_post_recv(priv->qp, &priv->rx_wr, &bad_wr);
+       if (unlikely(ret)) {
+               ipoib_warn(priv, "receive failed for buf %d (%d)\n", id, ret);
+               ipoib_ud_dma_unmap_rx(priv, priv->rx_ring[id].mapping);
+               dev_kfree_skb_any(priv->rx_ring[id].skb);
+               priv->rx_ring[id].skb = NULL;
+       }
+
+       return ret;
+}
+
+static struct sk_buff *ipoib_alloc_rx_skb(struct net_device *dev, int id)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       struct sk_buff *skb;
+       int buf_size;
+       u64 *mapping;
+
+       buf_size = IPOIB_UD_BUF_SIZE(priv->max_ib_mtu);
+
+       skb = dev_alloc_skb(buf_size + IPOIB_ENCAP_LEN);
+       if (unlikely(!skb))
+               return NULL;
+
+       /*
+        * 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);
+
+       mapping = priv->rx_ring[id].mapping;
+       mapping[0] = ib_dma_map_single(priv->ca, skb->data, buf_size,
+                                      DMA_FROM_DEVICE);
+       if (unlikely(ib_dma_mapping_error(priv->ca, mapping[0])))
+               goto error;
+
+       priv->rx_ring[id].skb = skb;
+       return skb;
+error:
+       dev_kfree_skb_any(skb);
+       return NULL;
+}
+
+static int ipoib_ib_post_receives(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       int i;
+
+       for (i = 0; i < ipoib_recvq_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;
+               }
+       }
+
+       return 0;
+}
+
+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 & ~IPOIB_OP_RECV;
+       struct sk_buff *skb;
+       u64 mapping[IPOIB_UD_RX_SG];
+       union ib_gid *dgid;
+
+       ipoib_dbg_data(priv, "recv completion: id %d, status: %d\n",
+                      wr_id, wc->status);
+
+       if (unlikely(wr_id >= ipoib_recvq_size)) {
+               ipoib_warn(priv, "recv completion event with wrid %d (> %d)\n",
+                          wr_id, ipoib_recvq_size);
+               return;
+       }
+
+       skb  = priv->rx_ring[wr_id].skb;
+
+       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);
+               ipoib_ud_dma_unmap_rx(priv, priv->rx_ring[wr_id].mapping);
+               dev_kfree_skb_any(skb);
+               priv->rx_ring[wr_id].skb = NULL;
+               return;
+       }
+
+       /*
+        * Drop packets that this interface sent, ie multicast packets
+        * that the HCA has replicated.
+        */
+       if (wc->slid == priv->local_lid && wc->src_qp == priv->qp->qp_num)
+               goto repost;
+
+       memcpy(mapping, priv->rx_ring[wr_id].mapping,
+              IPOIB_UD_RX_SG * sizeof *mapping);
+
+       /*
+        * 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))) {
+               ++dev->stats.rx_dropped;
+               goto repost;
+       }
+
+       ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
+                      wc->byte_len, wc->slid);
+
+       ipoib_ud_dma_unmap_rx(priv, mapping);
+
+       skb_put(skb, wc->byte_len);
+
+       /* First byte of dgid signals multicast when 0xff */
+       dgid = &((struct ib_grh *)skb->data)->dgid;
+
+       if (!(wc->wc_flags & IB_WC_GRH) || dgid->raw[0] != 0xff)
+               skb->pkt_type = PACKET_HOST;
+       else if (memcmp(dgid, dev->broadcast + 4, sizeof(union ib_gid)) == 0)
+               skb->pkt_type = PACKET_BROADCAST;
+       else
+               skb->pkt_type = PACKET_MULTICAST;
+
+       skb_pull(skb, IB_GRH_BYTES);
+
+       skb->protocol = ((struct ipoib_header *) skb->data)->proto;
+       skb_reset_mac_header(skb);
+       skb_pull(skb, IPOIB_ENCAP_LEN);
+
+       skb->truesize = SKB_TRUESIZE(skb->len);
+
+       ++dev->stats.rx_packets;
+       dev->stats.rx_bytes += skb->len;
+
+       skb->dev = dev;
+       if ((dev->features & NETIF_F_RXCSUM) &&
+                       likely(wc->wc_flags & IB_WC_IP_CSUM_OK))
+               skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+       napi_gro_receive(&priv->napi, skb);
+
+repost:
+       if (unlikely(ipoib_ib_post_receive(dev, wr_id)))
+               ipoib_warn(priv, "ipoib_ib_post_receive failed "
+                          "for buf %d\n", wr_id);
+}
+
+static int ipoib_dma_map_tx(struct ib_device *ca,
+                           struct ipoib_tx_buf *tx_req)
+{
+       struct sk_buff *skb = tx_req->skb;
+       u64 *mapping = tx_req->mapping;
+       int i;
+       int off;
+
+       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) {
+               const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+               mapping[i + off] = ib_dma_map_page(ca,
+                                                skb_frag_page(frag),
+                                                frag->page_offset, skb_frag_size(frag),
+                                                DMA_TO_DEVICE);
+               if (unlikely(ib_dma_mapping_error(ca, mapping[i + off])))
+                       goto partial_error;
+       }
+       return 0;
+
+partial_error:
+       for (; i > 0; --i) {
+               const skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
+
+               ib_dma_unmap_page(ca, mapping[i - !off], skb_frag_size(frag), DMA_TO_DEVICE);
+       }
+
+       if (off)
+               ib_dma_unmap_single(ca, mapping[0], skb_headlen(skb), DMA_TO_DEVICE);
+
+       return -EIO;
+}
+
+static void ipoib_dma_unmap_tx(struct ib_device *ca,
+                              struct ipoib_tx_buf *tx_req)
+{
+       struct sk_buff *skb = tx_req->skb;
+       u64 *mapping = tx_req->mapping;
+       int i;
+       int off;
+
+       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) {
+               const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+               ib_dma_unmap_page(ca, mapping[i + off], skb_frag_size(frag),
+                                 DMA_TO_DEVICE);
+       }
+}
+
+/*
+ * As the result of a completion error the QP Can be transferred to SQE states.
+ * The function checks if the (send)QP is in SQE state and
+ * moves it back to RTS state, that in order to have it functional again.
+ */
+static void ipoib_qp_state_validate_work(struct work_struct *work)
+{
+       struct ipoib_qp_state_validate *qp_work =
+               container_of(work, struct ipoib_qp_state_validate, work);
+
+       struct ipoib_dev_priv *priv = qp_work->priv;
+       struct ib_qp_attr qp_attr;
+       struct ib_qp_init_attr query_init_attr;
+       int ret;
+
+       ret = ib_query_qp(priv->qp, &qp_attr, IB_QP_STATE, &query_init_attr);
+       if (ret) {
+               ipoib_warn(priv, "%s: Failed to query QP ret: %d\n",
+                          __func__, ret);
+               goto free_res;
+       }
+       pr_info("%s: QP: 0x%x is in state: %d\n",
+               __func__, priv->qp->qp_num, qp_attr.qp_state);
+
+       /* currently support only in SQE->RTS transition*/
+       if (qp_attr.qp_state == IB_QPS_SQE) {
+               qp_attr.qp_state = IB_QPS_RTS;
+
+               ret = ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE);
+               if (ret) {
+                       pr_warn("failed(%d) modify QP:0x%x SQE->RTS\n",
+                               ret, priv->qp->qp_num);
+                       goto free_res;
+               }
+               pr_info("%s: QP: 0x%x moved from IB_QPS_SQE to IB_QPS_RTS\n",
+                       __func__, priv->qp->qp_num);
+       } else {
+               pr_warn("QP (%d) will stay in state: %d\n",
+                       priv->qp->qp_num, qp_attr.qp_state);
+       }
+
+free_res:
+       kfree(qp_work);
+}
+
+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;
+
+       ipoib_dbg_data(priv, "send completion: id %d, status: %d\n",
+                      wr_id, wc->status);
+
+       if (unlikely(wr_id >= ipoib_sendq_size)) {
+               ipoib_warn(priv, "send completion event with wrid %d (> %d)\n",
+                          wr_id, ipoib_sendq_size);
+               return;
+       }
+
+       tx_req = &priv->tx_ring[wr_id];
+
+       ipoib_dma_unmap_tx(priv->ca, tx_req);
+
+       ++dev->stats.tx_packets;
+       dev->stats.tx_bytes += tx_req->skb->len;
+
+       dev_kfree_skb_any(tx_req->skb);
+
+       ++priv->tx_tail;
+       if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
+           netif_queue_stopped(dev) &&
+           test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
+               netif_wake_queue(dev);
+
+       if (wc->status != IB_WC_SUCCESS &&
+           wc->status != IB_WC_WR_FLUSH_ERR) {
+               struct ipoib_qp_state_validate *qp_work;
+               ipoib_warn(priv, "failed send event "
+                          "(status=%d, wrid=%d vend_err %x)\n",
+                          wc->status, wr_id, wc->vendor_err);
+               qp_work = kzalloc(sizeof(*qp_work), GFP_ATOMIC);
+               if (!qp_work) {
+                       ipoib_warn(priv, "%s Failed alloc ipoib_qp_state_validate for qp: 0x%x\n",
+                                  __func__, priv->qp->qp_num);
+                       return;
+               }
+
+               INIT_WORK(&qp_work->work, ipoib_qp_state_validate_work);
+               qp_work->priv = priv;
+               queue_work(priv->wq, &qp_work->work);
+       }
+}
+
+static int poll_tx(struct ipoib_dev_priv *priv)
+{
+       int n, i;
+
+       n = ib_poll_cq(priv->send_cq, MAX_SEND_CQE, priv->send_wc);
+       for (i = 0; i < n; ++i)
+               ipoib_ib_handle_tx_wc(priv->dev, priv->send_wc + i);
+
+       return n == MAX_SEND_CQE;
+}
+
+int ipoib_poll(struct napi_struct *napi, int budget)
+{
+       struct ipoib_dev_priv *priv = container_of(napi, struct ipoib_dev_priv, napi);
+       struct net_device *dev = priv->dev;
+       int done;
+       int t;
+       int n, i;
+
+       done  = 0;
+
+poll_more:
+       while (done < budget) {
+               int max = (budget - done);
+
+               t = min(IPOIB_NUM_WC, max);
+               n = ib_poll_cq(priv->recv_cq, t, priv->ibwc);
+
+               for (i = 0; i < n; i++) {
+                       struct ib_wc *wc = priv->ibwc + i;
+
+                       if (wc->wr_id & IPOIB_OP_RECV) {
+                               ++done;
+                               if (wc->wr_id & IPOIB_OP_CM)
+                                       ipoib_cm_handle_rx_wc(dev, wc);
+                               else
+                                       ipoib_ib_handle_rx_wc(dev, wc);
+                       } else
+                               ipoib_cm_handle_tx_wc(priv->dev, wc);
+               }
+
+               if (n != t)
+                       break;
+       }
+
+       if (done < budget) {
+               napi_complete(napi);
+               if (unlikely(ib_req_notify_cq(priv->recv_cq,
+                                             IB_CQ_NEXT_COMP |
+                                             IB_CQ_REPORT_MISSED_EVENTS)) &&
+                   napi_reschedule(napi))
+                       goto poll_more;
+       }
+
+       return done;
+}
+
+void ipoib_ib_completion(struct ib_cq *cq, void *dev_ptr)
+{
+       struct net_device *dev = dev_ptr;
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       napi_schedule(&priv->napi);
+}
+
+static void drain_tx_cq(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       netif_tx_lock(dev);
+       while (poll_tx(priv))
+               ; /* nothing */
+
+       if (netif_queue_stopped(dev))
+               mod_timer(&priv->poll_timer, jiffies + 1);
+
+       netif_tx_unlock(dev);
+}
+
+void ipoib_send_comp_handler(struct ib_cq *cq, void *dev_ptr)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev_ptr);
+
+       mod_timer(&priv->poll_timer, jiffies);
+}
+
+static inline int post_send(struct ipoib_dev_priv *priv,
+                           unsigned int wr_id,
+                           struct ib_ah *address, u32 qpn,
+                           struct ipoib_tx_buf *tx_req,
+                           void *head, int hlen)
+{
+       struct ib_send_wr *bad_wr;
+       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;
+
+       for (i = 0; i < nr_frags; ++i) {
+               priv->tx_sge[i + off].addr = mapping[i + off];
+               priv->tx_sge[i + off].length = skb_frag_size(&frags[i]);
+       }
+       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);
+}
+
+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_tx_buf *tx_req;
+       int hlen, rc;
+       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",
+                      skb->len, address, qpn);
+
+       /*
+        * We put the skb into the tx_ring _before_ we call post_send()
+        * because it's entirely possible that the completion handler will
+        * run before we execute anything after the post_send().  That
+        * means we have to make sure everything is properly recorded and
+        * our state is consistent before we call post_send().
+        */
+       tx_req = &priv->tx_ring[priv->tx_head & (ipoib_sendq_size - 1)];
+       tx_req->skb = skb;
+       if (unlikely(ipoib_dma_map_tx(priv->ca, tx_req))) {
+               ++dev->stats.tx_errors;
+               dev_kfree_skb_any(skb);
+               return;
+       }
+
+       if (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 (++priv->tx_outstanding == ipoib_sendq_size) {
+               ipoib_dbg(priv, "TX ring full, stopping kernel net queue\n");
+               if (ib_req_notify_cq(priv->send_cq, IB_CQ_NEXT_COMP))
+                       ipoib_warn(priv, "request notify on send CQ failed\n");
+               netif_stop_queue(dev);
+       }
+
+       skb_orphan(skb);
+       skb_dst_drop(skb);
+
+       rc = post_send(priv, priv->tx_head & (ipoib_sendq_size - 1),
+                      address->ah, qpn, tx_req, phead, hlen);
+       if (unlikely(rc)) {
+               ipoib_warn(priv, "post_send failed, error %d\n", rc);
+               ++dev->stats.tx_errors;
+               --priv->tx_outstanding;
+               ipoib_dma_unmap_tx(priv->ca, tx_req);
+               dev_kfree_skb_any(skb);
+               if (netif_queue_stopped(dev))
+                       netif_wake_queue(dev);
+       } else {
+               dev->trans_start = jiffies;
+
+               address->last_send = priv->tx_head;
+               ++priv->tx_head;
+       }
+
+       if (unlikely(priv->tx_outstanding > MAX_SEND_CQE))
+               while (poll_tx(priv))
+                       ; /* nothing */
+}
+
+static void __ipoib_reap_ah(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       struct ipoib_ah *ah, *tah;
+       LIST_HEAD(remove_list);
+       unsigned long flags;
+
+       netif_tx_lock_bh(dev);
+       spin_lock_irqsave(&priv->lock, flags);
+
+       list_for_each_entry_safe(ah, tah, &priv->dead_ahs, list)
+               if ((int) priv->tx_tail - (int) ah->last_send >= 0) {
+                       list_del(&ah->list);
+                       ib_destroy_ah(ah->ah);
+                       kfree(ah);
+               }
+
+       spin_unlock_irqrestore(&priv->lock, flags);
+       netif_tx_unlock_bh(dev);
+}
+
+void ipoib_reap_ah(struct work_struct *work)
+{
+       struct ipoib_dev_priv *priv =
+               container_of(work, struct ipoib_dev_priv, ah_reap_task.work);
+       struct net_device *dev = priv->dev;
+
+       __ipoib_reap_ah(dev);
+
+       if (!test_bit(IPOIB_STOP_REAPER, &priv->flags))
+               queue_delayed_work(priv->wq, &priv->ah_reap_task,
+                                  round_jiffies_relative(HZ));
+}
+
+static void ipoib_flush_ah(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       cancel_delayed_work(&priv->ah_reap_task);
+       flush_workqueue(priv->wq);
+       ipoib_reap_ah(&priv->ah_reap_task.work);
+}
+
+static void ipoib_stop_ah(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       set_bit(IPOIB_STOP_REAPER, &priv->flags);
+       ipoib_flush_ah(dev);
+}
+
+static void ipoib_ib_tx_timer_func(unsigned long ctx)
+{
+       drain_tx_cq((struct net_device *)ctx);
+}
+
+int ipoib_ib_dev_open(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       int ret;
+
+       ipoib_pkey_dev_check_presence(dev);
+
+       if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags)) {
+               ipoib_warn(priv, "P_Key 0x%04x is %s\n", priv->pkey,
+                          (!(priv->pkey & 0x7fff) ? "Invalid" : "not found"));
+               return -1;
+       }
+
+       ret = ipoib_init_qp(dev);
+       if (ret) {
+               ipoib_warn(priv, "ipoib_init_qp returned %d\n", ret);
+               return -1;
+       }
+
+       ret = ipoib_ib_post_receives(dev);
+       if (ret) {
+               ipoib_warn(priv, "ipoib_ib_post_receives returned %d\n", ret);
+               goto dev_stop;
+       }
+
+       ret = ipoib_cm_dev_open(dev);
+       if (ret) {
+               ipoib_warn(priv, "ipoib_cm_dev_open returned %d\n", ret);
+               goto dev_stop;
+       }
+
+       clear_bit(IPOIB_STOP_REAPER, &priv->flags);
+       queue_delayed_work(priv->wq, &priv->ah_reap_task,
+                          round_jiffies_relative(HZ));
+
+       if (!test_and_set_bit(IPOIB_FLAG_INITIALIZED, &priv->flags))
+               napi_enable(&priv->napi);
+
+       return 0;
+dev_stop:
+       if (!test_and_set_bit(IPOIB_FLAG_INITIALIZED, &priv->flags))
+               napi_enable(&priv->napi);
+       ipoib_ib_dev_stop(dev);
+       return -1;
+}
+
+void ipoib_pkey_dev_check_presence(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       if (!(priv->pkey & 0x7fff) ||
+           ib_find_pkey(priv->ca, priv->port, priv->pkey,
+                        &priv->pkey_index))
+               clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
+       else
+               set_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
+}
+
+int ipoib_ib_dev_up(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       ipoib_pkey_dev_check_presence(dev);
+
+       if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags)) {
+               ipoib_dbg(priv, "PKEY is not assigned.\n");
+               return 0;
+       }
+
+       set_bit(IPOIB_FLAG_OPER_UP, &priv->flags);
+
+       return ipoib_mcast_start_thread(dev);
+}
+
+int ipoib_ib_dev_down(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       ipoib_dbg(priv, "downing ib_dev\n");
+
+       clear_bit(IPOIB_FLAG_OPER_UP, &priv->flags);
+       netif_carrier_off(dev);
+
+       ipoib_mcast_stop_thread(dev);
+       ipoib_mcast_dev_flush(dev);
+
+       ipoib_flush_paths(dev);
+
+       return 0;
+}
+
+static int recvs_pending(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       int pending = 0;
+       int i;
+
+       for (i = 0; i < ipoib_recvq_size; ++i)
+               if (priv->rx_ring[i].skb)
+                       ++pending;
+
+       return pending;
+}
+
+void ipoib_drain_cq(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       int i, n;
+
+       /*
+        * We call completion handling routines that expect to be
+        * called from the BH-disabled NAPI poll context, so disable
+        * BHs here too.
+        */
+       local_bh_disable();
+
+       do {
+               n = ib_poll_cq(priv->recv_cq, IPOIB_NUM_WC, priv->ibwc);
+               for (i = 0; i < n; ++i) {
+                       /*
+                        * Convert any successful completions to flush
+                        * errors to avoid passing packets up the
+                        * stack after bringing the device down.
+                        */
+                       if (priv->ibwc[i].status == IB_WC_SUCCESS)
+                               priv->ibwc[i].status = IB_WC_WR_FLUSH_ERR;
+
+                       if (priv->ibwc[i].wr_id & IPOIB_OP_RECV) {
+                               if (priv->ibwc[i].wr_id & IPOIB_OP_CM)
+                                       ipoib_cm_handle_rx_wc(dev, priv->ibwc + i);
+                               else
+                                       ipoib_ib_handle_rx_wc(dev, priv->ibwc + i);
+                       } else
+                               ipoib_cm_handle_tx_wc(dev, priv->ibwc + i);
+               }
+       } while (n == IPOIB_NUM_WC);
+
+       while (poll_tx(priv))
+               ; /* nothing */
+
+       local_bh_enable();
+}
+
+int ipoib_ib_dev_stop(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+       struct ib_qp_attr qp_attr;
+       unsigned long begin;
+       struct ipoib_tx_buf *tx_req;
+       int i;
+
+       if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &priv->flags))
+               napi_disable(&priv->napi);
+
+       ipoib_cm_dev_stop(dev);
+
+       /*
+        * Move our QP to the error state and then reinitialize in
+        * when all work requests have completed or have been flushed.
+        */
+       qp_attr.qp_state = IB_QPS_ERR;
+       if (ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE))
+               ipoib_warn(priv, "Failed to modify QP to ERROR state\n");
+
+       /* Wait for all sends and receives to complete */
+       begin = jiffies;
+
+       while (priv->tx_head != priv->tx_tail || recvs_pending(dev)) {
+               if (time_after(jiffies, begin + 5 * HZ)) {
+                       ipoib_warn(priv, "timing out; %d sends %d receives not completed\n",
+                                  priv->tx_head - priv->tx_tail, recvs_pending(dev));
+
+                       /*
+                        * assume the HW is wedged and just free up
+                        * all our pending work requests.
+                        */
+                       while ((int) priv->tx_tail - (int) priv->tx_head < 0) {
+                               tx_req = &priv->tx_ring[priv->tx_tail &
+                                                       (ipoib_sendq_size - 1)];
+                               ipoib_dma_unmap_tx(priv->ca, tx_req);
+                               dev_kfree_skb_any(tx_req->skb);
+                               ++priv->tx_tail;
+                               --priv->tx_outstanding;
+                       }
+
+                       for (i = 0; i < ipoib_recvq_size; ++i) {
+                               struct ipoib_rx_buf *rx_req;
+
+                               rx_req = &priv->rx_ring[i];
+                               if (!rx_req->skb)
+                                       continue;
+                               ipoib_ud_dma_unmap_rx(priv,
+                                                     priv->rx_ring[i].mapping);
+                               dev_kfree_skb_any(rx_req->skb);
+                               rx_req->skb = NULL;
+                       }
+
+                       goto timeout;
+               }
+
+               ipoib_drain_cq(dev);
+
+               msleep(1);
+       }
+
+       ipoib_dbg(priv, "All sends and receives done.\n");
+
+timeout:
+       del_timer_sync(&priv->poll_timer);
+       qp_attr.qp_state = IB_QPS_RESET;
+       if (ib_modify_qp(priv->qp, &qp_attr, IB_QP_STATE))
+               ipoib_warn(priv, "Failed to modify QP to RESET state\n");
+
+       ipoib_flush_ah(dev);
+
+       ib_req_notify_cq(priv->recv_cq, IB_CQ_NEXT_COMP);
+
+       return 0;
+}
+
+int ipoib_ib_dev_init(struct net_device *dev, struct ib_device *ca, int port)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       priv->ca = ca;
+       priv->port = port;
+       priv->qp = NULL;
+
+       if (ipoib_transport_dev_init(dev, ca)) {
+               printk(KERN_WARNING "%s: ipoib_transport_dev_init failed\n", ca->name);
+               return -ENODEV;
+       }
+
+       setup_timer(&priv->poll_timer, ipoib_ib_tx_timer_func,
+                   (unsigned long) dev);
+
+       if (dev->flags & IFF_UP) {
+               if (ipoib_ib_dev_open(dev)) {
+                       ipoib_transport_dev_cleanup(dev);
+                       return -ENODEV;
+               }
+       }
+
+       return 0;
+}
+
+/*
+ * Takes whatever value which is in pkey index 0 and updates priv->pkey
+ * returns 0 if the pkey value was changed.
+ */
+static inline int update_parent_pkey(struct ipoib_dev_priv *priv)
+{
+       int result;
+       u16 prev_pkey;
+
+       prev_pkey = priv->pkey;
+       result = ib_query_pkey(priv->ca, priv->port, 0, &priv->pkey);
+       if (result) {
+               ipoib_warn(priv, "ib_query_pkey port %d failed (ret = %d)\n",
+                          priv->port, result);
+               return result;
+       }
+
+       priv->pkey |= 0x8000;
+
+       if (prev_pkey != priv->pkey) {
+               ipoib_dbg(priv, "pkey changed from 0x%x to 0x%x\n",
+                         prev_pkey, priv->pkey);
+               /*
+                * Update the pkey in the broadcast address, while making sure to set
+                * the full membership bit, so that we join the right broadcast group.
+                */
+               priv->dev->broadcast[8] = priv->pkey >> 8;
+               priv->dev->broadcast[9] = priv->pkey & 0xff;
+               return 0;
+       }
+
+       return 1;
+}
+/*
+ * returns 0 if pkey value was found in a different slot.
+ */
+static inline int update_child_pkey(struct ipoib_dev_priv *priv)
+{
+       u16 old_index = priv->pkey_index;
+
+       priv->pkey_index = 0;
+       ipoib_pkey_dev_check_presence(priv->dev);
+
+       if (test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags) &&
+           (old_index == priv->pkey_index))
+               return 1;
+       return 0;
+}
+
+static void __ipoib_ib_dev_flush(struct ipoib_dev_priv *priv,
+                               enum ipoib_flush_level level)
+{
+       struct ipoib_dev_priv *cpriv;
+       struct net_device *dev = priv->dev;
+       int result;
+
+       down_read(&priv->vlan_rwsem);
+
+       /*
+        * Flush any child interfaces too -- they might be up even if
+        * the parent is down.
+        */
+       list_for_each_entry(cpriv, &priv->child_intfs, list)
+               __ipoib_ib_dev_flush(cpriv, level);
+
+       up_read(&priv->vlan_rwsem);
+
+       if (!test_bit(IPOIB_FLAG_INITIALIZED, &priv->flags) &&
+           level != IPOIB_FLUSH_HEAVY) {
+               ipoib_dbg(priv, "Not flushing - IPOIB_FLAG_INITIALIZED not set.\n");
+               return;
+       }
+
+       if (!test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags)) {
+               /* interface is down. update pkey and leave. */
+               if (level == IPOIB_FLUSH_HEAVY) {
+                       if (!test_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags))
+                               update_parent_pkey(priv);
+                       else
+                               update_child_pkey(priv);
+               }
+               ipoib_dbg(priv, "Not flushing - IPOIB_FLAG_ADMIN_UP not set.\n");
+               return;
+       }
+
+       if (level == IPOIB_FLUSH_HEAVY) {
+               /* child devices chase their origin pkey value, while non-child
+                * (parent) devices should always takes what present in pkey index 0
+                */
+               if (test_bit(IPOIB_FLAG_SUBINTERFACE, &priv->flags)) {
+                       result = update_child_pkey(priv);
+                       if (result) {
+                               /* restart QP only if P_Key index is changed */
+                               ipoib_dbg(priv, "Not flushing - P_Key index not changed.\n");
+                               return;
+                       }
+
+               } else {
+                       result = update_parent_pkey(priv);
+                       /* restart QP only if P_Key value changed */
+                       if (result) {
+                               ipoib_dbg(priv, "Not flushing - P_Key value not changed.\n");
+                               return;
+                       }
+               }
+       }
+
+       if (level == IPOIB_FLUSH_LIGHT) {
+               ipoib_mark_paths_invalid(dev);
+               ipoib_mcast_dev_flush(dev);
+               ipoib_flush_ah(dev);
+       }
+
+       if (level >= IPOIB_FLUSH_NORMAL)
+               ipoib_ib_dev_down(dev);
+
+       if (level == IPOIB_FLUSH_HEAVY) {
+               if (test_bit(IPOIB_FLAG_INITIALIZED, &priv->flags))
+                       ipoib_ib_dev_stop(dev);
+               if (ipoib_ib_dev_open(dev) != 0)
+                       return;
+               if (netif_queue_stopped(dev))
+                       netif_start_queue(dev);
+       }
+
+       /*
+        * The device could have been brought down between the start and when
+        * we get here, don't bring it back up if it's not configured up
+        */
+       if (test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags)) {
+               if (level >= IPOIB_FLUSH_NORMAL)
+                       ipoib_ib_dev_up(dev);
+               ipoib_mcast_restart_task(&priv->restart_task);
+       }
+}
+
+void ipoib_ib_dev_flush_light(struct work_struct *work)
+{
+       struct ipoib_dev_priv *priv =
+               container_of(work, struct ipoib_dev_priv, flush_light);
+
+       __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_LIGHT);
+}
+
+void ipoib_ib_dev_flush_normal(struct work_struct *work)
+{
+       struct ipoib_dev_priv *priv =
+               container_of(work, struct ipoib_dev_priv, flush_normal);
+
+       __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_NORMAL);
+}
+
+void ipoib_ib_dev_flush_heavy(struct work_struct *work)
+{
+       struct ipoib_dev_priv *priv =
+               container_of(work, struct ipoib_dev_priv, flush_heavy);
+
+       __ipoib_ib_dev_flush(priv, IPOIB_FLUSH_HEAVY);
+}
+
+void ipoib_ib_dev_cleanup(struct net_device *dev)
+{
+       struct ipoib_dev_priv *priv = netdev_priv(dev);
+
+       ipoib_dbg(priv, "cleaning up ib_dev\n");
+       /*
+        * We must make sure there are no more (path) completions
+        * that may wish to touch priv fields that are no longer valid
+        */
+       ipoib_flush_paths(dev);
+
+       ipoib_mcast_stop_thread(dev);
+       ipoib_mcast_dev_flush(dev);
+
+       /*
+        * All of our ah references aren't free until after
+        * ipoib_mcast_dev_flush(), ipoib_flush_paths, and
+        * the neighbor garbage collection is stopped and reaped.
+        * That should all be done now, so make a final ah flush.
+        */
+       ipoib_stop_ah(dev);
+
+       ipoib_transport_dev_cleanup(dev);
+}
+
+