drivers/infiniband/ulp/ipoib/ipoib_cm.c

   1 /*
   2  * Copyright (c) 2006 Mellanox Technologies. All rights reserved
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  *
  32  * $Id$
  33  */
  34
  35 #include <rdma/ib_cm.h>
  36 #include <rdma/ib_cache.h>
  37 #include <net/dst.h>
  38 #include <net/icmp.h>
  39 #include <linux/icmpv6.h>
  40 #include <linux/delay.h>
  41
  42 #ifdef CONFIG_INFINIBAND_IPOIB_DEBUG_DATA
  43 static int data_debug_level;
  44
  45 module_param_named(cm_data_debug_level, data_debug_level, int, 0644);
  46 MODULE_PARM_DESC(cm_data_debug_level,
  47                  "Enable data path debug tracing for connected mode if > 0");
  48 #endif
  49
  50 #include "ipoib.h"
  51
  52 #define IPOIB_CM_IETF_ID 0x1000000000000000ULL
  53
  54 #define IPOIB_CM_RX_UPDATE_TIME (256 * HZ)
  55 #define IPOIB_CM_RX_TIMEOUT     (2 * 256 * HZ)
  56 #define IPOIB_CM_RX_DELAY       (3 * 256 * HZ)
  57 #define IPOIB_CM_RX_UPDATE_MASK (0x3)
  58
  59 struct ipoib_cm_id {
  60         struct ib_cm_id *id;
  61         int flags;
  62         u32 remote_qpn;
  63         u32 remote_mtu;
  64 };
  65
  66 static struct ib_qp_attr ipoib_cm_err_attr = {
  67         .qp_state = IB_QPS_ERR
  68 };
  69
  70 #define IPOIB_CM_RX_DRAIN_WRID 0x7fffffff
  71
  72 static struct ib_recv_wr ipoib_cm_rx_drain_wr = {
  73         .wr_id = IPOIB_CM_RX_DRAIN_WRID
  74 };
  75
  76 static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
  77                                struct ib_cm_event *event);
  78
  79 static void ipoib_cm_dma_unmap_rx(struct ipoib_dev_priv *priv, int frags,
  80                                   u64 mapping[IPOIB_CM_RX_SG])
  81 {
  82         int i;
  83
  84         ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_CM_HEAD_SIZE, DMA_FROM_DEVICE);
  85
  86         for (i = 0; i < frags; ++i)
  87                 ib_dma_unmap_single(priv->ca, mapping[i + 1], PAGE_SIZE, DMA_FROM_DEVICE);
  88 }
  89
  90 static int ipoib_cm_post_receive(struct net_device *dev, int id)
  91 {
  92         struct ipoib_dev_priv *priv = netdev_priv(dev);
  93         struct ib_recv_wr *bad_wr;
  94         int i, ret;
  95
  96         priv->cm.rx_wr.wr_id = id | IPOIB_CM_OP_SRQ;
  97
  98         for (i = 0; i < IPOIB_CM_RX_SG; ++i)
  99                 priv->cm.rx_sge[i].addr = priv->cm.srq_ring[id].mapping[i];
 100
 101         ret = ib_post_srq_recv(priv->cm.srq, &priv->cm.rx_wr, &bad_wr);
 102         if (unlikely(ret)) {
 103                 ipoib_warn(priv, "post srq failed for buf %d (%d)\n", id, ret);
 104                 ipoib_cm_dma_unmap_rx(priv, IPOIB_CM_RX_SG - 1,
 105                                       priv->cm.srq_ring[id].mapping);
 106                 dev_kfree_skb_any(priv->cm.srq_ring[id].skb);
 107                 priv->cm.srq_ring[id].skb = NULL;
 108         }
 109
 110         return ret;
 111 }
 112
 113 static struct sk_buff *ipoib_cm_alloc_rx_skb(struct net_device *dev, int id, int frags,
 114                                              u64 mapping[IPOIB_CM_RX_SG])
 115 {
 116         struct ipoib_dev_priv *priv = netdev_priv(dev);
 117         struct sk_buff *skb;
 118         int i;
 119
 120         skb = dev_alloc_skb(IPOIB_CM_HEAD_SIZE + 12);
 121         if (unlikely(!skb))
 122                 return NULL;
 123
 124         /*
 125          * IPoIB adds a 4 byte header. So we need 12 more bytes to align the
 126          * IP header to a multiple of 16.
 127          */
 128         skb_reserve(skb, 12);
 129
 130         mapping[0] = ib_dma_map_single(priv->ca, skb->data, IPOIB_CM_HEAD_SIZE,
 131                                        DMA_FROM_DEVICE);
 132         if (unlikely(ib_dma_mapping_error(priv->ca, mapping[0]))) {
 133                 dev_kfree_skb_any(skb);
 134                 return NULL;
 135         }
 136
 137         for (i = 0; i < frags; i++) {
 138                 struct page *page = alloc_page(GFP_ATOMIC);
 139
 140                 if (!page)
 141                         goto partial_error;
 142                 skb_fill_page_desc(skb, i, page, 0, PAGE_SIZE);
 143
 144                 mapping[i + 1] = ib_dma_map_page(priv->ca, skb_shinfo(skb)->frags[i].page,
 145                                                  0, PAGE_SIZE, DMA_FROM_DEVICE);
 146                 if (unlikely(ib_dma_mapping_error(priv->ca, mapping[i + 1])))
 147                         goto partial_error;
 148         }
 149
 150         priv->cm.srq_ring[id].skb = skb;
 151         return skb;
 152
 153 partial_error:
 154
 155         ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_CM_HEAD_SIZE, DMA_FROM_DEVICE);
 156
 157         for (; i >= 0; --i)
 158                 ib_dma_unmap_single(priv->ca, mapping[i + 1], PAGE_SIZE, DMA_FROM_DEVICE);
 159
 160         dev_kfree_skb_any(skb);
 161         return NULL;
 162 }
 163
 164 static void ipoib_cm_start_rx_drain(struct ipoib_dev_priv* priv)
 165 {
 166         struct ib_recv_wr *bad_wr;
 167
 168         /* rx_drain_qp send queue depth is 1, so
 169          * make sure we have at most 1 outstanding WR. */
 170         if (list_empty(&priv->cm.rx_flush_list) ||
 171             !list_empty(&priv->cm.rx_drain_list))
 172                 return;
 173
 174         if (ib_post_recv(priv->cm.rx_drain_qp, &ipoib_cm_rx_drain_wr, &bad_wr))
 175                 ipoib_warn(priv, "failed to post rx_drain wr\n");
 176
 177         list_splice_init(&priv->cm.rx_flush_list, &priv->cm.rx_drain_list);
 178 }
 179
 180 static void ipoib_cm_rx_event_handler(struct ib_event *event, void *ctx)
 181 {
 182         struct ipoib_cm_rx *p = ctx;
 183         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 184         unsigned long flags;
 185
 186         if (event->event != IB_EVENT_QP_LAST_WQE_REACHED)
 187                 return;
 188
 189         spin_lock_irqsave(&priv->lock, flags);
 190         list_move(&p->list, &priv->cm.rx_flush_list);
 191         p->state = IPOIB_CM_RX_FLUSH;
 192         ipoib_cm_start_rx_drain(priv);
 193         spin_unlock_irqrestore(&priv->lock, flags);
 194 }
 195
 196 static struct ib_qp *ipoib_cm_create_rx_qp(struct net_device *dev,
 197                                            struct ipoib_cm_rx *p)
 198 {
 199         struct ipoib_dev_priv *priv = netdev_priv(dev);
 200         struct ib_qp_init_attr attr = {
 201                 .event_handler = ipoib_cm_rx_event_handler,
 202                 .send_cq = priv->cq, /* does not matter, we never send anything */
 203                 .recv_cq = priv->cq,
 204                 .srq = priv->cm.srq,
 205                 .cap.max_send_wr = 1, /* FIXME: 0 Seems not to work */
 206                 .cap.max_send_sge = 1, /* FIXME: 0 Seems not to work */
 207                 .sq_sig_type = IB_SIGNAL_ALL_WR,
 208                 .qp_type = IB_QPT_RC,
 209                 .qp_context = p,
 210         };
 211         return ib_create_qp(priv->pd, &attr);
 212 }
 213
 214 static int ipoib_cm_modify_rx_qp(struct net_device *dev,
 215                                   struct ib_cm_id *cm_id, struct ib_qp *qp,
 216                                   unsigned psn)
 217 {
 218         struct ipoib_dev_priv *priv = netdev_priv(dev);
 219         struct ib_qp_attr qp_attr;
 220         int qp_attr_mask, ret;
 221
 222         qp_attr.qp_state = IB_QPS_INIT;
 223         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 224         if (ret) {
 225                 ipoib_warn(priv, "failed to init QP attr for INIT: %d\n", ret);
 226                 return ret;
 227         }
 228         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
 229         if (ret) {
 230                 ipoib_warn(priv, "failed to modify QP to INIT: %d\n", ret);
 231                 return ret;
 232         }
 233         qp_attr.qp_state = IB_QPS_RTR;
 234         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 235         if (ret) {
 236                 ipoib_warn(priv, "failed to init QP attr for RTR: %d\n", ret);
 237                 return ret;
 238         }
 239         qp_attr.rq_psn = psn;
 240         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
 241         if (ret) {
 242                 ipoib_warn(priv, "failed to modify QP to RTR: %d\n", ret);
 243                 return ret;
 244         }
 245         return 0;
 246 }
 247
 248 static int ipoib_cm_send_rep(struct net_device *dev, struct ib_cm_id *cm_id,
 249                              struct ib_qp *qp, struct ib_cm_req_event_param *req,
 250                              unsigned psn)
 251 {
 252         struct ipoib_dev_priv *priv = netdev_priv(dev);
 253         struct ipoib_cm_data data = {};
 254         struct ib_cm_rep_param rep = {};
 255
 256         data.qpn = cpu_to_be32(priv->qp->qp_num);
 257         data.mtu = cpu_to_be32(IPOIB_CM_BUF_SIZE);
 258
 259         rep.private_data = &data;
 260         rep.private_data_len = sizeof data;
 261         rep.flow_control = 0;
 262         rep.rnr_retry_count = req->rnr_retry_count;
 263         rep.target_ack_delay = 20; /* FIXME */
 264         rep.srq = 1;
 265         rep.qp_num = qp->qp_num;
 266         rep.starting_psn = psn;
 267         return ib_send_cm_rep(cm_id, &rep);
 268 }
 269
 270 static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 271 {
 272         struct net_device *dev = cm_id->context;
 273         struct ipoib_dev_priv *priv = netdev_priv(dev);
 274         struct ipoib_cm_rx *p;
 275         unsigned psn;
 276         int ret;
 277
 278         ipoib_dbg(priv, "REQ arrived\n");
 279         p = kzalloc(sizeof *p, GFP_KERNEL);
 280         if (!p)
 281                 return -ENOMEM;
 282         p->dev = dev;
 283         p->id = cm_id;
 284         p->qp = ipoib_cm_create_rx_qp(dev, p);
 285         if (IS_ERR(p->qp)) {
 286                 ret = PTR_ERR(p->qp);
 287                 goto err_qp;
 288         }
 289
 290         psn = random32() & 0xffffff;
 291         ret = ipoib_cm_modify_rx_qp(dev, cm_id, p->qp, psn);
 292         if (ret)
 293                 goto err_modify;
 294
 295         ret = ipoib_cm_send_rep(dev, cm_id, p->qp, &event->param.req_rcvd, psn);
 296         if (ret) {
 297                 ipoib_warn(priv, "failed to send REP: %d\n", ret);
 298                 goto err_rep;
 299         }
 300
 301         cm_id->context = p;
 302         p->jiffies = jiffies;
 303         p->state = IPOIB_CM_RX_LIVE;
 304         spin_lock_irq(&priv->lock);
 305         if (list_empty(&priv->cm.passive_ids))
 306                 queue_delayed_work(ipoib_workqueue,
 307                                    &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
 308         list_add(&p->list, &priv->cm.passive_ids);
 309         spin_unlock_irq(&priv->lock);
 310         return 0;
 311
 312 err_rep:
 313 err_modify:
 314         ib_destroy_qp(p->qp);
 315 err_qp:
 316         kfree(p);
 317         return ret;
 318 }
 319
 320 static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
 321                                struct ib_cm_event *event)
 322 {
 323         struct ipoib_cm_rx *p;
 324         struct ipoib_dev_priv *priv;
 325
 326         switch (event->event) {
 327         case IB_CM_REQ_RECEIVED:
 328                 return ipoib_cm_req_handler(cm_id, event);
 329         case IB_CM_DREQ_RECEIVED:
 330                 p = cm_id->context;
 331                 ib_send_cm_drep(cm_id, NULL, 0);
 332                 /* Fall through */
 333         case IB_CM_REJ_RECEIVED:
 334                 p = cm_id->context;
 335                 priv = netdev_priv(p->dev);
 336                 if (ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE))
 337                         ipoib_warn(priv, "unable to move qp to error state\n");
 338                 /* Fall through */
 339         default:
 340                 return 0;
 341         }
 342 }
 343 /* Adjust length of skb with fragments to match received data */
 344 static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
 345                           unsigned int length, struct sk_buff *toskb)
 346 {
 347         int i, num_frags;
 348         unsigned int size;
 349
 350         /* put header into skb */
 351         size = min(length, hdr_space);
 352         skb->tail += size;
 353         skb->len += size;
 354         length -= size;
 355
 356         num_frags = skb_shinfo(skb)->nr_frags;
 357         for (i = 0; i < num_frags; i++) {
 358                 skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 359
 360                 if (length == 0) {
 361                         /* don't need this page */
 362                         skb_fill_page_desc(toskb, i, frag->page, 0, PAGE_SIZE);
 363                         --skb_shinfo(skb)->nr_frags;
 364                 } else {
 365                         size = min(length, (unsigned) PAGE_SIZE);
 366
 367                         frag->size = size;
 368                         skb->data_len += size;
 369                         skb->truesize += size;
 370                         skb->len += size;
 371                         length -= size;
 372                 }
 373         }
 374 }
 375
 376 void ipoib_cm_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
 377 {
 378         struct ipoib_dev_priv *priv = netdev_priv(dev);
 379         unsigned int wr_id = wc->wr_id & ~IPOIB_CM_OP_SRQ;
 380         struct sk_buff *skb, *newskb;
 381         struct ipoib_cm_rx *p;
 382         unsigned long flags;
 383         u64 mapping[IPOIB_CM_RX_SG];
 384         int frags;
 385
 386         ipoib_dbg_data(priv, "cm recv completion: id %d, status: %d\n",
 387                        wr_id, wc->status);
 388
 389         if (unlikely(wr_id >= ipoib_recvq_size)) {
 390                 if (wr_id == (IPOIB_CM_RX_DRAIN_WRID & ~IPOIB_CM_OP_SRQ)) {
 391                         spin_lock_irqsave(&priv->lock, flags);
 392                         list_splice_init(&priv->cm.rx_drain_list, &priv->cm.rx_reap_list);
 393                         ipoib_cm_start_rx_drain(priv);
 394                         queue_work(ipoib_workqueue, &priv->cm.rx_reap_task);
 395                         spin_unlock_irqrestore(&priv->lock, flags);
 396                 } else
 397                         ipoib_warn(priv, "cm recv completion event with wrid %d (> %d)\n",
 398                                    wr_id, ipoib_recvq_size);
 399                 return;
 400         }
 401
 402         skb  = priv->cm.srq_ring[wr_id].skb;
 403
 404         if (unlikely(wc->status != IB_WC_SUCCESS)) {
 405                 ipoib_dbg(priv, "cm recv error "
 406                            "(status=%d, wrid=%d vend_err %x)\n",
 407                            wc->status, wr_id, wc->vendor_err);
 408                 ++priv->stats.rx_dropped;
 409                 goto repost;
 410         }
 411
 412         if (!likely(wr_id & IPOIB_CM_RX_UPDATE_MASK)) {
 413                 p = wc->qp->qp_context;
 414                 if (p && time_after_eq(jiffies, p->jiffies + IPOIB_CM_RX_UPDATE_TIME)) {
 415                         spin_lock_irqsave(&priv->lock, flags);
 416                         p->jiffies = jiffies;
 417                         /* Move this entry to list head, but do not re-add it
 418                          * if it has been moved out of list. */
 419                         if (p->state == IPOIB_CM_RX_LIVE)
 420                                 list_move(&p->list, &priv->cm.passive_ids);
 421                         spin_unlock_irqrestore(&priv->lock, flags);
 422                 }
 423         }
 424
 425         frags = PAGE_ALIGN(wc->byte_len - min(wc->byte_len,
 426                                               (unsigned)IPOIB_CM_HEAD_SIZE)) / PAGE_SIZE;
 427
 428         newskb = ipoib_cm_alloc_rx_skb(dev, wr_id, frags, mapping);
 429         if (unlikely(!newskb)) {
 430                 /*
 431                  * If we can't allocate a new RX buffer, dump
 432                  * this packet and reuse the old buffer.
 433                  */
 434                 ipoib_dbg(priv, "failed to allocate receive buffer %d\n", wr_id);
 435                 ++priv->stats.rx_dropped;
 436                 goto repost;
 437         }
 438
 439         ipoib_cm_dma_unmap_rx(priv, frags, priv->cm.srq_ring[wr_id].mapping);
 440         memcpy(priv->cm.srq_ring[wr_id].mapping, mapping, (frags + 1) * sizeof *mapping);
 441
 442         ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
 443                        wc->byte_len, wc->slid);
 444
 445         skb_put_frags(skb, IPOIB_CM_HEAD_SIZE, wc->byte_len, newskb);
 446
 447         skb->protocol = ((struct ipoib_header *) skb->data)->proto;
 448         skb_reset_mac_header(skb);
 449         skb_pull(skb, IPOIB_ENCAP_LEN);
 450
 451         dev->last_rx = jiffies;
 452         ++priv->stats.rx_packets;
 453         priv->stats.rx_bytes += skb->len;
 454
 455         skb->dev = dev;
 456         /* XXX get correct PACKET_ type here */
 457         skb->pkt_type = PACKET_HOST;
 458         netif_receive_skb(skb);
 459
 460 repost:
 461         if (unlikely(ipoib_cm_post_receive(dev, wr_id)))
 462                 ipoib_warn(priv, "ipoib_cm_post_receive failed "
 463                            "for buf %d\n", wr_id);
 464 }
 465
 466 static inline int post_send(struct ipoib_dev_priv *priv,
 467                             struct ipoib_cm_tx *tx,
 468                             unsigned int wr_id,
 469                             u64 addr, int len)
 470 {
 471         struct ib_send_wr *bad_wr;
 472
 473         priv->tx_sge.addr             = addr;
 474         priv->tx_sge.length           = len;
 475
 476         priv->tx_wr.wr_id             = wr_id;
 477
 478         return ib_post_send(tx->qp, &priv->tx_wr, &bad_wr);
 479 }
 480
 481 void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_tx *tx)
 482 {
 483         struct ipoib_dev_priv *priv = netdev_priv(dev);
 484         struct ipoib_tx_buf *tx_req;
 485         u64 addr;
 486
 487         if (unlikely(skb->len > tx->mtu)) {
 488                 ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n",
 489                            skb->len, tx->mtu);
 490                 ++priv->stats.tx_dropped;
 491                 ++priv->stats.tx_errors;
 492                 ipoib_cm_skb_too_long(dev, skb, tx->mtu - IPOIB_ENCAP_LEN);
 493                 return;
 494         }
 495
 496         ipoib_dbg_data(priv, "sending packet: head 0x%x length %d connection 0x%x\n",
 497                        tx->tx_head, skb->len, tx->qp->qp_num);
 498
 499         /*
 500          * We put the skb into the tx_ring _before_ we call post_send()
 501          * because it's entirely possible that the completion handler will
 502          * run before we execute anything after the post_send().  That
 503          * means we have to make sure everything is properly recorded and
 504          * our state is consistent before we call post_send().
 505          */
 506         tx_req = &tx->tx_ring[tx->tx_head & (ipoib_sendq_size - 1)];
 507         tx_req->skb = skb;
 508         addr = ib_dma_map_single(priv->ca, skb->data, skb->len, DMA_TO_DEVICE);
 509         if (unlikely(ib_dma_mapping_error(priv->ca, addr))) {
 510                 ++priv->stats.tx_errors;
 511                 dev_kfree_skb_any(skb);
 512                 return;
 513         }
 514
 515         tx_req->mapping = addr;
 516
 517         if (unlikely(post_send(priv, tx, tx->tx_head & (ipoib_sendq_size - 1),
 518                                 addr, skb->len))) {
 519                 ipoib_warn(priv, "post_send failed\n");
 520                 ++priv->stats.tx_errors;
 521                 ib_dma_unmap_single(priv->ca, addr, skb->len, DMA_TO_DEVICE);
 522                 dev_kfree_skb_any(skb);
 523         } else {
 524                 dev->trans_start = jiffies;
 525                 ++tx->tx_head;
 526
 527                 if (tx->tx_head - tx->tx_tail == ipoib_sendq_size) {
 528                         ipoib_dbg(priv, "TX ring 0x%x full, stopping kernel net queue\n",
 529                                   tx->qp->qp_num);
 530                         netif_stop_queue(dev);
 531                         set_bit(IPOIB_FLAG_NETIF_STOPPED, &tx->flags);
 532                 }
 533         }
 534 }
 535
 536 static void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ipoib_cm_tx *tx,
 537                                   struct ib_wc *wc)
 538 {
 539         struct ipoib_dev_priv *priv = netdev_priv(dev);
 540         unsigned int wr_id = wc->wr_id;
 541         struct ipoib_tx_buf *tx_req;
 542         unsigned long flags;
 543
 544         ipoib_dbg_data(priv, "cm send completion: id %d, status: %d\n",
 545                        wr_id, wc->status);
 546
 547         if (unlikely(wr_id >= ipoib_sendq_size)) {
 548                 ipoib_warn(priv, "cm send completion event with wrid %d (> %d)\n",
 549                            wr_id, ipoib_sendq_size);
 550                 return;
 551         }
 552
 553         tx_req = &tx->tx_ring[wr_id];
 554
 555         ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len, DMA_TO_DEVICE);
 556
 557         /* FIXME: is this right? Shouldn't we only increment on success? */
 558         ++priv->stats.tx_packets;
 559         priv->stats.tx_bytes += tx_req->skb->len;
 560
 561         dev_kfree_skb_any(tx_req->skb);
 562
 563         spin_lock_irqsave(&priv->tx_lock, flags);
 564         ++tx->tx_tail;
 565         if (unlikely(test_bit(IPOIB_FLAG_NETIF_STOPPED, &tx->flags)) &&
 566             tx->tx_head - tx->tx_tail <= ipoib_sendq_size >> 1) {
 567                 clear_bit(IPOIB_FLAG_NETIF_STOPPED, &tx->flags);
 568                 netif_wake_queue(dev);
 569         }
 570
 571         if (wc->status != IB_WC_SUCCESS &&
 572             wc->status != IB_WC_WR_FLUSH_ERR) {
 573                 struct ipoib_neigh *neigh;
 574
 575                 ipoib_dbg(priv, "failed cm send event "
 576                            "(status=%d, wrid=%d vend_err %x)\n",
 577                            wc->status, wr_id, wc->vendor_err);
 578
 579                 spin_lock(&priv->lock);
 580                 neigh = tx->neigh;
 581
 582                 if (neigh) {
 583                         neigh->cm = NULL;
 584                         list_del(&neigh->list);
 585                         if (neigh->ah)
 586                                 ipoib_put_ah(neigh->ah);
 587                         ipoib_neigh_free(dev, neigh);
 588
 589                         tx->neigh = NULL;
 590                 }
 591
 592                 /* queue would be re-started anyway when TX is destroyed,
 593                  * but it makes sense to do it ASAP here. */
 594                 if (test_and_clear_bit(IPOIB_FLAG_NETIF_STOPPED, &tx->flags))
 595                         netif_wake_queue(dev);
 596
 597                 if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
 598                         list_move(&tx->list, &priv->cm.reap_list);
 599                         queue_work(ipoib_workqueue, &priv->cm.reap_task);
 600                 }
 601
 602                 clear_bit(IPOIB_FLAG_OPER_UP, &tx->flags);
 603
 604                 spin_unlock(&priv->lock);
 605         }
 606
 607         spin_unlock_irqrestore(&priv->tx_lock, flags);
 608 }
 609
 610 static void ipoib_cm_tx_completion(struct ib_cq *cq, void *tx_ptr)
 611 {
 612         struct ipoib_cm_tx *tx = tx_ptr;
 613         int n, i;
 614
 615         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
 616         do {
 617                 n = ib_poll_cq(cq, IPOIB_NUM_WC, tx->ibwc);
 618                 for (i = 0; i < n; ++i)
 619                         ipoib_cm_handle_tx_wc(tx->dev, tx, tx->ibwc + i);
 620         } while (n == IPOIB_NUM_WC);
 621 }
 622
 623 int ipoib_cm_dev_open(struct net_device *dev)
 624 {
 625         struct ipoib_dev_priv *priv = netdev_priv(dev);
 626         struct ib_qp_init_attr qp_init_attr = {
 627                 .send_cq = priv->cq,   /* does not matter, we never send anything */
 628                 .recv_cq = priv->cq,
 629                 .cap.max_send_wr = 1,  /* FIXME: 0 Seems not to work */
 630                 .cap.max_send_sge = 1, /* FIXME: 0 Seems not to work */
 631                 .cap.max_recv_wr = 1,
 632                 .cap.max_recv_sge = 1, /* FIXME: 0 Seems not to work */
 633                 .sq_sig_type = IB_SIGNAL_ALL_WR,
 634                 .qp_type = IB_QPT_UC,
 635         };
 636         int ret;
 637
 638         if (!IPOIB_CM_SUPPORTED(dev->dev_addr))
 639                 return 0;
 640
 641         priv->cm.rx_drain_qp = ib_create_qp(priv->pd, &qp_init_attr);
 642         if (IS_ERR(priv->cm.rx_drain_qp)) {
 643                 printk(KERN_WARNING "%s: failed to create CM ID\n", priv->ca->name);
 644                 ret = PTR_ERR(priv->cm.rx_drain_qp);
 645                 return ret;
 646         }
 647
 648         /*
 649          * We put the QP in error state directly.  This way, a "flush
 650          * error" WC will be immediately generated for each WR we post.
 651          */
 652         ret = ib_modify_qp(priv->cm.rx_drain_qp, &ipoib_cm_err_attr, IB_QP_STATE);
 653         if (ret) {
 654                 ipoib_warn(priv, "failed to modify drain QP to error: %d\n", ret);
 655                 goto err_qp;
 656         }
 657
 658         priv->cm.id = ib_create_cm_id(priv->ca, ipoib_cm_rx_handler, dev);
 659         if (IS_ERR(priv->cm.id)) {
 660                 printk(KERN_WARNING "%s: failed to create CM ID\n", priv->ca->name);
 661                 ret = PTR_ERR(priv->cm.id);
 662                 goto err_cm;
 663         }
 664
 665         ret = ib_cm_listen(priv->cm.id, cpu_to_be64(IPOIB_CM_IETF_ID | priv->qp->qp_num),
 666                            0, NULL);
 667         if (ret) {
 668                 printk(KERN_WARNING "%s: failed to listen on ID 0x%llx\n", priv->ca->name,
 669                        IPOIB_CM_IETF_ID | priv->qp->qp_num);
 670                 goto err_listen;
 671         }
 672
 673         return 0;
 674
 675 err_listen:
 676         ib_destroy_cm_id(priv->cm.id);
 677 err_cm:
 678         priv->cm.id = NULL;
 679 err_qp:
 680         ib_destroy_qp(priv->cm.rx_drain_qp);
 681         return ret;
 682 }
 683
 684 void ipoib_cm_dev_stop(struct net_device *dev)
 685 {
 686         struct ipoib_dev_priv *priv = netdev_priv(dev);
 687         struct ipoib_cm_rx *p, *n;
 688         unsigned long begin;
 689         LIST_HEAD(list);
 690         int ret;
 691
 692         if (!IPOIB_CM_SUPPORTED(dev->dev_addr) || !priv->cm.id)
 693                 return;
 694
 695         ib_destroy_cm_id(priv->cm.id);
 696         priv->cm.id = NULL;
 697
 698         spin_lock_irq(&priv->lock);
 699         while (!list_empty(&priv->cm.passive_ids)) {
 700                 p = list_entry(priv->cm.passive_ids.next, typeof(*p), list);
 701                 list_move(&p->list, &priv->cm.rx_error_list);
 702                 p->state = IPOIB_CM_RX_ERROR;
 703                 spin_unlock_irq(&priv->lock);
 704                 ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
 705                 if (ret)
 706                         ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
 707                 spin_lock_irq(&priv->lock);
 708         }
 709
 710         /* Wait for all RX to be drained */
 711         begin = jiffies;
 712
 713         while (!list_empty(&priv->cm.rx_error_list) ||
 714                !list_empty(&priv->cm.rx_flush_list) ||
 715                !list_empty(&priv->cm.rx_drain_list)) {
 716                 if (time_after(jiffies, begin + 5 * HZ)) {
 717                         ipoib_warn(priv, "RX drain timing out\n");
 718
 719                         /*
 720                          * assume the HW is wedged and just free up everything.
 721                          */
 722                         list_splice_init(&priv->cm.rx_flush_list, &list);
 723                         list_splice_init(&priv->cm.rx_error_list, &list);
 724                         list_splice_init(&priv->cm.rx_drain_list, &list);
 725                         break;
 726                 }
 727                 spin_unlock_irq(&priv->lock);
 728                 msleep(1);
 729                 spin_lock_irq(&priv->lock);
 730         }
 731
 732         list_splice_init(&priv->cm.rx_reap_list, &list);
 733
 734         spin_unlock_irq(&priv->lock);
 735
 736         list_for_each_entry_safe(p, n, &list, list) {
 737                 ib_destroy_cm_id(p->id);
 738                 ib_destroy_qp(p->qp);
 739                 kfree(p);
 740         }
 741
 742         ib_destroy_qp(priv->cm.rx_drain_qp);
 743         cancel_delayed_work(&priv->cm.stale_task);
 744 }
 745
 746 static int ipoib_cm_rep_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 747 {
 748         struct ipoib_cm_tx *p = cm_id->context;
 749         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 750         struct ipoib_cm_data *data = event->private_data;
 751         struct sk_buff_head skqueue;
 752         struct ib_qp_attr qp_attr;
 753         int qp_attr_mask, ret;
 754         struct sk_buff *skb;
 755
 756         p->mtu = be32_to_cpu(data->mtu);
 757
 758         if (p->mtu < priv->dev->mtu + IPOIB_ENCAP_LEN) {
 759                 ipoib_warn(priv, "Rejecting connection: mtu %d < device mtu %d + 4\n",
 760                            p->mtu, priv->dev->mtu);
 761                 return -EINVAL;
 762         }
 763
 764         qp_attr.qp_state = IB_QPS_RTR;
 765         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 766         if (ret) {
 767                 ipoib_warn(priv, "failed to init QP attr for RTR: %d\n", ret);
 768                 return ret;
 769         }
 770
 771         qp_attr.rq_psn = 0 /* FIXME */;
 772         ret = ib_modify_qp(p->qp, &qp_attr, qp_attr_mask);
 773         if (ret) {
 774                 ipoib_warn(priv, "failed to modify QP to RTR: %d\n", ret);
 775                 return ret;
 776         }
 777
 778         qp_attr.qp_state = IB_QPS_RTS;
 779         ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 780         if (ret) {
 781                 ipoib_warn(priv, "failed to init QP attr for RTS: %d\n", ret);
 782                 return ret;
 783         }
 784         ret = ib_modify_qp(p->qp, &qp_attr, qp_attr_mask);
 785         if (ret) {
 786                 ipoib_warn(priv, "failed to modify QP to RTS: %d\n", ret);
 787                 return ret;
 788         }
 789
 790         skb_queue_head_init(&skqueue);
 791
 792         spin_lock_irq(&priv->lock);
 793         set_bit(IPOIB_FLAG_OPER_UP, &p->flags);
 794         if (p->neigh)
 795                 while ((skb = __skb_dequeue(&p->neigh->queue)))
 796                         __skb_queue_tail(&skqueue, skb);
 797         spin_unlock_irq(&priv->lock);
 798
 799         while ((skb = __skb_dequeue(&skqueue))) {
 800                 skb->dev = p->dev;
 801                 if (dev_queue_xmit(skb))
 802                         ipoib_warn(priv, "dev_queue_xmit failed "
 803                                    "to requeue packet\n");
 804         }
 805
 806         ret = ib_send_cm_rtu(cm_id, NULL, 0);
 807         if (ret) {
 808                 ipoib_warn(priv, "failed to send RTU: %d\n", ret);
 809                 return ret;
 810         }
 811         return 0;
 812 }
 813
 814 static struct ib_qp *ipoib_cm_create_tx_qp(struct net_device *dev, struct ib_cq *cq)
 815 {
 816         struct ipoib_dev_priv *priv = netdev_priv(dev);
 817         struct ib_qp_init_attr attr = {};
 818         attr.recv_cq = priv->cq;
 819         attr.srq = priv->cm.srq;
 820         attr.cap.max_send_wr = ipoib_sendq_size;
 821         attr.cap.max_send_sge = 1;
 822         attr.sq_sig_type = IB_SIGNAL_ALL_WR;
 823         attr.qp_type = IB_QPT_RC;
 824         attr.send_cq = cq;
 825         return ib_create_qp(priv->pd, &attr);
 826 }
 827
 828 static int ipoib_cm_send_req(struct net_device *dev,
 829                              struct ib_cm_id *id, struct ib_qp *qp,
 830                              u32 qpn,
 831                              struct ib_sa_path_rec *pathrec)
 832 {
 833         struct ipoib_dev_priv *priv = netdev_priv(dev);
 834         struct ipoib_cm_data data = {};
 835         struct ib_cm_req_param req = {};
 836
 837         data.qpn = cpu_to_be32(priv->qp->qp_num);
 838         data.mtu = cpu_to_be32(IPOIB_CM_BUF_SIZE);
 839
 840         req.primary_path              = pathrec;
 841         req.alternate_path            = NULL;
 842         req.service_id                = cpu_to_be64(IPOIB_CM_IETF_ID | qpn);
 843         req.qp_num                    = qp->qp_num;
 844         req.qp_type                   = qp->qp_type;
 845         req.private_data              = &data;
 846         req.private_data_len          = sizeof data;
 847         req.flow_control              = 0;
 848
 849         req.starting_psn              = 0; /* FIXME */
 850
 851         /*
 852          * Pick some arbitrary defaults here; we could make these
 853          * module parameters if anyone cared about setting them.
 854          */
 855         req.responder_resources       = 4;
 856         req.remote_cm_response_timeout = 20;
 857         req.local_cm_response_timeout  = 20;
 858         req.retry_count               = 0; /* RFC draft warns against retries */
 859         req.rnr_retry_count           = 0; /* RFC draft warns against retries */
 860         req.max_cm_retries            = 15;
 861         req.srq                       = 1;
 862         return ib_send_cm_req(id, &req);
 863 }
 864
 865 static int ipoib_cm_modify_tx_init(struct net_device *dev,
 866                                   struct ib_cm_id *cm_id, struct ib_qp *qp)
 867 {
 868         struct ipoib_dev_priv *priv = netdev_priv(dev);
 869         struct ib_qp_attr qp_attr;
 870         int qp_attr_mask, ret;
 871         ret = ib_find_cached_pkey(priv->ca, priv->port, priv->pkey, &qp_attr.pkey_index);
 872         if (ret) {
 873                 ipoib_warn(priv, "pkey 0x%x not in cache: %d\n", priv->pkey, ret);
 874                 return ret;
 875         }
 876
 877         qp_attr.qp_state = IB_QPS_INIT;
 878         qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE;
 879         qp_attr.port_num = priv->port;
 880         qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PKEY_INDEX | IB_QP_PORT;
 881
 882         ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
 883         if (ret) {
 884                 ipoib_warn(priv, "failed to modify tx QP to INIT: %d\n", ret);
 885                 return ret;
 886         }
 887         return 0;
 888 }
 889
 890 static int ipoib_cm_tx_init(struct ipoib_cm_tx *p, u32 qpn,
 891                             struct ib_sa_path_rec *pathrec)
 892 {
 893         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 894         int ret;
 895
 896         p->tx_ring = kzalloc(ipoib_sendq_size * sizeof *p->tx_ring,
 897                                 GFP_KERNEL);
 898         if (!p->tx_ring) {
 899                 ipoib_warn(priv, "failed to allocate tx ring\n");
 900                 ret = -ENOMEM;
 901                 goto err_tx;
 902         }
 903
 904         p->cq = ib_create_cq(priv->ca, ipoib_cm_tx_completion, NULL, p,
 905                              ipoib_sendq_size + 1, 0);
 906         if (IS_ERR(p->cq)) {
 907                 ret = PTR_ERR(p->cq);
 908                 ipoib_warn(priv, "failed to allocate tx cq: %d\n", ret);
 909                 goto err_cq;
 910         }
 911
 912         ret = ib_req_notify_cq(p->cq, IB_CQ_NEXT_COMP);
 913         if (ret) {
 914                 ipoib_warn(priv, "failed to request completion notification: %d\n", ret);
 915                 goto err_req_notify;
 916         }
 917
 918         p->qp = ipoib_cm_create_tx_qp(p->dev, p->cq);
 919         if (IS_ERR(p->qp)) {
 920                 ret = PTR_ERR(p->qp);
 921                 ipoib_warn(priv, "failed to allocate tx qp: %d\n", ret);
 922                 goto err_qp;
 923         }
 924
 925         p->id = ib_create_cm_id(priv->ca, ipoib_cm_tx_handler, p);
 926         if (IS_ERR(p->id)) {
 927                 ret = PTR_ERR(p->id);
 928                 ipoib_warn(priv, "failed to create tx cm id: %d\n", ret);
 929                 goto err_id;
 930         }
 931
 932         ret = ipoib_cm_modify_tx_init(p->dev, p->id,  p->qp);
 933         if (ret) {
 934                 ipoib_warn(priv, "failed to modify tx qp to rtr: %d\n", ret);
 935                 goto err_modify;
 936         }
 937
 938         ret = ipoib_cm_send_req(p->dev, p->id, p->qp, qpn, pathrec);
 939         if (ret) {
 940                 ipoib_warn(priv, "failed to send cm req: %d\n", ret);
 941                 goto err_send_cm;
 942         }
 943
 944         ipoib_dbg(priv, "Request connection 0x%x for gid " IPOIB_GID_FMT " qpn 0x%x\n",
 945                   p->qp->qp_num, IPOIB_GID_ARG(pathrec->dgid), qpn);
 946
 947         return 0;
 948
 949 err_send_cm:
 950 err_modify:
 951         ib_destroy_cm_id(p->id);
 952 err_id:
 953         p->id = NULL;
 954         ib_destroy_qp(p->qp);
 955 err_req_notify:
 956 err_qp:
 957         p->qp = NULL;
 958         ib_destroy_cq(p->cq);
 959 err_cq:
 960         p->cq = NULL;
 961 err_tx:
 962         return ret;
 963 }
 964
 965 static void ipoib_cm_tx_destroy(struct ipoib_cm_tx *p)
 966 {
 967         struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 968         struct ipoib_tx_buf *tx_req;
 969
 970         ipoib_dbg(priv, "Destroy active connection 0x%x head 0x%x tail 0x%x\n",
 971                   p->qp ? p->qp->qp_num : 0, p->tx_head, p->tx_tail);
 972
 973         if (p->id)
 974                 ib_destroy_cm_id(p->id);
 975
 976         if (p->qp)
 977                 ib_destroy_qp(p->qp);
 978
 979         if (p->cq)
 980                 ib_destroy_cq(p->cq);
 981
 982         if (test_bit(IPOIB_FLAG_NETIF_STOPPED, &p->flags))
 983                 netif_wake_queue(p->dev);
 984
 985         if (p->tx_ring) {
 986                 while ((int) p->tx_tail - (int) p->tx_head < 0) {
 987                         tx_req = &p->tx_ring[p->tx_tail & (ipoib_sendq_size - 1)];
 988                         ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len,
 989                                          DMA_TO_DEVICE);
 990                         dev_kfree_skb_any(tx_req->skb);
 991                         ++p->tx_tail;
 992                 }
 993
 994                 kfree(p->tx_ring);
 995         }
 996
 997         kfree(p);
 998 }
 999
1000 static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
1001                                struct ib_cm_event *event)
1002 {
1003         struct ipoib_cm_tx *tx = cm_id->context;
1004         struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
1005         struct net_device *dev = priv->dev;
1006         struct ipoib_neigh *neigh;
1007         int ret;
1008
1009         switch (event->event) {
1010         case IB_CM_DREQ_RECEIVED:
1011                 ipoib_dbg(priv, "DREQ received.\n");
1012                 ib_send_cm_drep(cm_id, NULL, 0);
1013                 break;
1014         case IB_CM_REP_RECEIVED:
1015                 ipoib_dbg(priv, "REP received.\n");
1016                 ret = ipoib_cm_rep_handler(cm_id, event);
1017                 if (ret)
1018                         ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED,
1019                                        NULL, 0, NULL, 0);
1020                 break;
1021         case IB_CM_REQ_ERROR:
1022         case IB_CM_REJ_RECEIVED:
1023         case IB_CM_TIMEWAIT_EXIT:
1024                 ipoib_dbg(priv, "CM error %d.\n", event->event);
1025                 spin_lock_irq(&priv->tx_lock);
1026                 spin_lock(&priv->lock);
1027                 neigh = tx->neigh;
1028
1029                 if (neigh) {
1030                         neigh->cm = NULL;
1031                         list_del(&neigh->list);
1032                         if (neigh->ah)
1033                                 ipoib_put_ah(neigh->ah);
1034                         ipoib_neigh_free(dev, neigh);
1035
1036                         tx->neigh = NULL;
1037                 }
1038
1039                 if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
1040                         list_move(&tx->list, &priv->cm.reap_list);
1041                         queue_work(ipoib_workqueue, &priv->cm.reap_task);
1042                 }
1043
1044                 spin_unlock(&priv->lock);
1045                 spin_unlock_irq(&priv->tx_lock);
1046                 break;
1047         default:
1048                 break;
1049         }
1050
1051         return 0;
1052 }
1053
1054 struct ipoib_cm_tx *ipoib_cm_create_tx(struct net_device *dev, struct ipoib_path *path,
1055                                        struct ipoib_neigh *neigh)
1056 {
1057         struct ipoib_dev_priv *priv = netdev_priv(dev);
1058         struct ipoib_cm_tx *tx;
1059
1060         tx = kzalloc(sizeof *tx, GFP_ATOMIC);
1061         if (!tx)
1062                 return NULL;
1063
1064         neigh->cm = tx;
1065         tx->neigh = neigh;
1066         tx->path = path;
1067         tx->dev = dev;
1068         list_add(&tx->list, &priv->cm.start_list);
1069         set_bit(IPOIB_FLAG_INITIALIZED, &tx->flags);
1070         queue_work(ipoib_workqueue, &priv->cm.start_task);
1071         return tx;
1072 }
1073
1074 void ipoib_cm_destroy_tx(struct ipoib_cm_tx *tx)
1075 {
1076         struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
1077         if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
1078                 list_move(&tx->list, &priv->cm.reap_list);
1079                 queue_work(ipoib_workqueue, &priv->cm.reap_task);
1080                 ipoib_dbg(priv, "Reap connection for gid " IPOIB_GID_FMT "\n",
1081                           IPOIB_GID_ARG(tx->neigh->dgid));
1082                 tx->neigh = NULL;
1083         }
1084 }
1085
1086 static void ipoib_cm_tx_start(struct work_struct *work)
1087 {
1088         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1089                                                    cm.start_task);
1090         struct net_device *dev = priv->dev;
1091         struct ipoib_neigh *neigh;
1092         struct ipoib_cm_tx *p;
1093         unsigned long flags;
1094         int ret;
1095
1096         struct ib_sa_path_rec pathrec;
1097         u32 qpn;
1098
1099         spin_lock_irqsave(&priv->tx_lock, flags);
1100         spin_lock(&priv->lock);
1101         while (!list_empty(&priv->cm.start_list)) {
1102                 p = list_entry(priv->cm.start_list.next, typeof(*p), list);
1103                 list_del_init(&p->list);
1104                 neigh = p->neigh;
1105                 qpn = IPOIB_QPN(neigh->neighbour->ha);
1106                 memcpy(&pathrec, &p->path->pathrec, sizeof pathrec);
1107                 spin_unlock(&priv->lock);
1108                 spin_unlock_irqrestore(&priv->tx_lock, flags);
1109                 ret = ipoib_cm_tx_init(p, qpn, &pathrec);
1110                 spin_lock_irqsave(&priv->tx_lock, flags);
1111                 spin_lock(&priv->lock);
1112                 if (ret) {
1113                         neigh = p->neigh;
1114                         if (neigh) {
1115                                 neigh->cm = NULL;
1116                                 list_del(&neigh->list);
1117                                 if (neigh->ah)
1118                                         ipoib_put_ah(neigh->ah);
1119                                 ipoib_neigh_free(dev, neigh);
1120                         }
1121                         list_del(&p->list);
1122                         kfree(p);
1123                 }
1124         }
1125         spin_unlock(&priv->lock);
1126         spin_unlock_irqrestore(&priv->tx_lock, flags);
1127 }
1128
1129 static void ipoib_cm_tx_reap(struct work_struct *work)
1130 {
1131         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1132                                                    cm.reap_task);
1133         struct ipoib_cm_tx *p;
1134
1135         spin_lock_irq(&priv->tx_lock);
1136         spin_lock(&priv->lock);
1137         while (!list_empty(&priv->cm.reap_list)) {
1138                 p = list_entry(priv->cm.reap_list.next, typeof(*p), list);
1139                 list_del(&p->list);
1140                 spin_unlock(&priv->lock);
1141                 spin_unlock_irq(&priv->tx_lock);
1142                 ipoib_cm_tx_destroy(p);
1143                 spin_lock_irq(&priv->tx_lock);
1144                 spin_lock(&priv->lock);
1145         }
1146         spin_unlock(&priv->lock);
1147         spin_unlock_irq(&priv->tx_lock);
1148 }
1149
1150 static void ipoib_cm_skb_reap(struct work_struct *work)
1151 {
1152         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1153                                                    cm.skb_task);
1154         struct net_device *dev = priv->dev;
1155         struct sk_buff *skb;
1156
1157         unsigned mtu = priv->mcast_mtu;
1158
1159         spin_lock_irq(&priv->tx_lock);
1160         spin_lock(&priv->lock);
1161         while ((skb = skb_dequeue(&priv->cm.skb_queue))) {
1162                 spin_unlock(&priv->lock);
1163                 spin_unlock_irq(&priv->tx_lock);
1164                 if (skb->protocol == htons(ETH_P_IP))
1165                         icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
1166 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1167                 else if (skb->protocol == htons(ETH_P_IPV6))
1168                         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev);
1169 #endif
1170                 dev_kfree_skb_any(skb);
1171                 spin_lock_irq(&priv->tx_lock);
1172                 spin_lock(&priv->lock);
1173         }
1174         spin_unlock(&priv->lock);
1175         spin_unlock_irq(&priv->tx_lock);
1176 }
1177
1178 void ipoib_cm_skb_too_long(struct net_device* dev, struct sk_buff *skb,
1179                            unsigned int mtu)
1180 {
1181         struct ipoib_dev_priv *priv = netdev_priv(dev);
1182         int e = skb_queue_empty(&priv->cm.skb_queue);
1183
1184         if (skb->dst)
1185                 skb->dst->ops->update_pmtu(skb->dst, mtu);
1186
1187         skb_queue_tail(&priv->cm.skb_queue, skb);
1188         if (e)
1189                 queue_work(ipoib_workqueue, &priv->cm.skb_task);
1190 }
1191
1192 static void ipoib_cm_rx_reap(struct work_struct *work)
1193 {
1194         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1195                                                    cm.rx_reap_task);
1196         struct ipoib_cm_rx *p, *n;
1197         LIST_HEAD(list);
1198
1199         spin_lock_irq(&priv->lock);
1200         list_splice_init(&priv->cm.rx_reap_list, &list);
1201         spin_unlock_irq(&priv->lock);
1202
1203         list_for_each_entry_safe(p, n, &list, list) {
1204                 ib_destroy_cm_id(p->id);
1205                 ib_destroy_qp(p->qp);
1206                 kfree(p);
1207         }
1208 }
1209
1210 static void ipoib_cm_stale_task(struct work_struct *work)
1211 {
1212         struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1213                                                    cm.stale_task.work);
1214         struct ipoib_cm_rx *p;
1215         int ret;
1216
1217         spin_lock_irq(&priv->lock);
1218         while (!list_empty(&priv->cm.passive_ids)) {
1219                 /* List is sorted by LRU, start from tail,
1220                  * stop when we see a recently used entry */
1221                 p = list_entry(priv->cm.passive_ids.prev, typeof(*p), list);
1222                 if (time_before_eq(jiffies, p->jiffies + IPOIB_CM_RX_TIMEOUT))
1223                         break;
1224                 list_move(&p->list, &priv->cm.rx_error_list);
1225                 p->state = IPOIB_CM_RX_ERROR;
1226                 spin_unlock_irq(&priv->lock);
1227                 ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
1228                 if (ret)
1229                         ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
1230                 spin_lock_irq(&priv->lock);
1231         }
1232
1233         if (!list_empty(&priv->cm.passive_ids))
1234                 queue_delayed_work(ipoib_workqueue,
1235                                    &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
1236         spin_unlock_irq(&priv->lock);
1237 }
1238
1239
1240 static ssize_t show_mode(struct device *d, struct device_attribute *attr,
1241                          char *buf)
1242 {
1243         struct ipoib_dev_priv *priv = netdev_priv(to_net_dev(d));
1244
1245         if (test_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags))
1246                 return sprintf(buf, "connected\n");
1247         else
1248                 return sprintf(buf, "datagram\n");
1249 }
1250
1251 static ssize_t set_mode(struct device *d, struct device_attribute *attr,
1252                         const char *buf, size_t count)
1253 {
1254         struct net_device *dev = to_net_dev(d);
1255         struct ipoib_dev_priv *priv = netdev_priv(dev);
1256
1257         /* flush paths if we switch modes so that connections are restarted */
1258         if (IPOIB_CM_SUPPORTED(dev->dev_addr) && !strcmp(buf, "connected\n")) {
1259                 set_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
1260                 ipoib_warn(priv, "enabling connected mode "
1261                            "will cause multicast packet drops\n");
1262                 ipoib_flush_paths(dev);
1263                 return count;
1264         }
1265
1266         if (!strcmp(buf, "datagram\n")) {
1267                 clear_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
1268                 dev->mtu = min(priv->mcast_mtu, dev->mtu);
1269                 ipoib_flush_paths(dev);
1270                 return count;
1271         }
1272
1273         return -EINVAL;
1274 }
1275
1276 static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO, show_mode, set_mode);
1277
1278 int ipoib_cm_add_mode_attr(struct net_device *dev)
1279 {
1280         return device_create_file(&dev->dev, &dev_attr_mode);
1281 }
1282
1283 int ipoib_cm_dev_init(struct net_device *dev)
1284 {
1285         struct ipoib_dev_priv *priv = netdev_priv(dev);
1286         struct ib_srq_init_attr srq_init_attr = {
1287                 .attr = {
1288                         .max_wr  = ipoib_recvq_size,
1289                         .max_sge = IPOIB_CM_RX_SG
1290                 }
1291         };
1292         int ret, i;
1293
1294         INIT_LIST_HEAD(&priv->cm.passive_ids);
1295         INIT_LIST_HEAD(&priv->cm.reap_list);
1296         INIT_LIST_HEAD(&priv->cm.start_list);
1297         INIT_LIST_HEAD(&priv->cm.rx_error_list);
1298         INIT_LIST_HEAD(&priv->cm.rx_flush_list);
1299         INIT_LIST_HEAD(&priv->cm.rx_drain_list);
1300         INIT_LIST_HEAD(&priv->cm.rx_reap_list);
1301         INIT_WORK(&priv->cm.start_task, ipoib_cm_tx_start);
1302         INIT_WORK(&priv->cm.reap_task, ipoib_cm_tx_reap);
1303         INIT_WORK(&priv->cm.skb_task, ipoib_cm_skb_reap);
1304         INIT_WORK(&priv->cm.rx_reap_task, ipoib_cm_rx_reap);
1305         INIT_DELAYED_WORK(&priv->cm.stale_task, ipoib_cm_stale_task);
1306
1307         skb_queue_head_init(&priv->cm.skb_queue);
1308
1309         priv->cm.srq = ib_create_srq(priv->pd, &srq_init_attr);
1310         if (IS_ERR(priv->cm.srq)) {
1311                 ret = PTR_ERR(priv->cm.srq);
1312                 priv->cm.srq = NULL;
1313                 return ret;
1314         }
1315
1316         priv->cm.srq_ring = kzalloc(ipoib_recvq_size * sizeof *priv->cm.srq_ring,
1317                                     GFP_KERNEL);
1318         if (!priv->cm.srq_ring) {
1319                 printk(KERN_WARNING "%s: failed to allocate CM ring (%d entries)\n",
1320                        priv->ca->name, ipoib_recvq_size);
1321                 ipoib_cm_dev_cleanup(dev);
1322                 return -ENOMEM;
1323         }
1324
1325         for (i = 0; i < IPOIB_CM_RX_SG; ++i)
1326                 priv->cm.rx_sge[i].lkey = priv->mr->lkey;
1327
1328         priv->cm.rx_sge[0].length = IPOIB_CM_HEAD_SIZE;
1329         for (i = 1; i < IPOIB_CM_RX_SG; ++i)
1330                 priv->cm.rx_sge[i].length = PAGE_SIZE;
1331         priv->cm.rx_wr.next = NULL;
1332         priv->cm.rx_wr.sg_list = priv->cm.rx_sge;
1333         priv->cm.rx_wr.num_sge = IPOIB_CM_RX_SG;
1334
1335         for (i = 0; i < ipoib_recvq_size; ++i) {
1336                 if (!ipoib_cm_alloc_rx_skb(dev, i, IPOIB_CM_RX_SG - 1,
1337                                            priv->cm.srq_ring[i].mapping)) {
1338                         ipoib_warn(priv, "failed to allocate receive buffer %d\n", i);
1339                         ipoib_cm_dev_cleanup(dev);
1340                         return -ENOMEM;
1341                 }
1342                 if (ipoib_cm_post_receive(dev, i)) {
1343                         ipoib_warn(priv, "ipoib_ib_post_receive failed for buf %d\n", i);
1344                         ipoib_cm_dev_cleanup(dev);
1345                         return -EIO;
1346                 }
1347         }
1348
1349         priv->dev->dev_addr[0] = IPOIB_FLAGS_RC;
1350         return 0;
1351 }
1352
1353 void ipoib_cm_dev_cleanup(struct net_device *dev)
1354 {
1355         struct ipoib_dev_priv *priv = netdev_priv(dev);
1356         int i, ret;
1357
1358         if (!priv->cm.srq)
1359                 return;
1360
1361         ipoib_dbg(priv, "Cleanup ipoib connected mode.\n");
1362
1363         ret = ib_destroy_srq(priv->cm.srq);
1364         if (ret)
1365                 ipoib_warn(priv, "ib_destroy_srq failed: %d\n", ret);
1366
1367         priv->cm.srq = NULL;
1368         if (!priv->cm.srq_ring)
1369                 return;
1370         for (i = 0; i < ipoib_recvq_size; ++i)
1371                 if (priv->cm.srq_ring[i].skb) {
1372                         ipoib_cm_dma_unmap_rx(priv, IPOIB_CM_RX_SG - 1,
1373                                               priv->cm.srq_ring[i].mapping);
1374                         dev_kfree_skb_any(priv->cm.srq_ring[i].skb);
1375                         priv->cm.srq_ring[i].skb = NULL;
1376                 }
1377         kfree(priv->cm.srq_ring);
1378         priv->cm.srq_ring = NULL;
1379 }