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