linux/drivers/infiniband/ulp/ipoib/ipoib_cm.c
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   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
  33#include <rdma/ib_cm.h>
  34#include <net/dst.h>
  35#include <net/icmp.h>
  36#include <linux/icmpv6.h>
  37#include <linux/delay.h>
  38#include <linux/vmalloc.h>
  39
  40#include "ipoib.h"
  41
  42int ipoib_max_conn_qp = 128;
  43
  44module_param_named(max_nonsrq_conn_qp, ipoib_max_conn_qp, int, 0444);
  45MODULE_PARM_DESC(max_nonsrq_conn_qp,
  46                 "Max number of connected-mode QPs per interface "
  47                 "(applied only if shared receive queue is not available)");
  48
  49#ifdef CONFIG_INFINIBAND_IPOIB_DEBUG_DATA
  50static int data_debug_level;
  51
  52module_param_named(cm_data_debug_level, data_debug_level, int, 0644);
  53MODULE_PARM_DESC(cm_data_debug_level,
  54                 "Enable data path debug tracing for connected mode if > 0");
  55#endif
  56
  57#define IPOIB_CM_IETF_ID 0x1000000000000000ULL
  58
  59#define IPOIB_CM_RX_UPDATE_TIME (256 * HZ)
  60#define IPOIB_CM_RX_TIMEOUT     (2 * 256 * HZ)
  61#define IPOIB_CM_RX_DELAY       (3 * 256 * HZ)
  62#define IPOIB_CM_RX_UPDATE_MASK (0x3)
  63
  64static struct ib_qp_attr ipoib_cm_err_attr = {
  65        .qp_state = IB_QPS_ERR
  66};
  67
  68#define IPOIB_CM_RX_DRAIN_WRID 0xffffffff
  69
  70static struct ib_send_wr ipoib_cm_rx_drain_wr = {
  71        .wr_id = IPOIB_CM_RX_DRAIN_WRID,
  72        .opcode = IB_WR_SEND,
  73};
  74
  75static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
  76                               struct ib_cm_event *event);
  77
  78static void ipoib_cm_dma_unmap_rx(struct ipoib_dev_priv *priv, int frags,
  79                                  u64 mapping[IPOIB_CM_RX_SG])
  80{
  81        int i;
  82
  83        ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_CM_HEAD_SIZE, DMA_FROM_DEVICE);
  84
  85        for (i = 0; i < frags; ++i)
  86                ib_dma_unmap_single(priv->ca, mapping[i + 1], PAGE_SIZE, DMA_FROM_DEVICE);
  87}
  88
  89static int ipoib_cm_post_receive_srq(struct net_device *dev, int id)
  90{
  91        struct ipoib_dev_priv *priv = netdev_priv(dev);
  92        struct ib_recv_wr *bad_wr;
  93        int i, ret;
  94
  95        priv->cm.rx_wr.wr_id = id | IPOIB_OP_CM | IPOIB_OP_RECV;
  96
  97        for (i = 0; i < priv->cm.num_frags; ++i)
  98                priv->cm.rx_sge[i].addr = priv->cm.srq_ring[id].mapping[i];
  99
 100        ret = ib_post_srq_recv(priv->cm.srq, &priv->cm.rx_wr, &bad_wr);
 101        if (unlikely(ret)) {
 102                ipoib_warn(priv, "post srq failed for buf %d (%d)\n", id, ret);
 103                ipoib_cm_dma_unmap_rx(priv, priv->cm.num_frags - 1,
 104                                      priv->cm.srq_ring[id].mapping);
 105                dev_kfree_skb_any(priv->cm.srq_ring[id].skb);
 106                priv->cm.srq_ring[id].skb = NULL;
 107        }
 108
 109        return ret;
 110}
 111
 112static int ipoib_cm_post_receive_nonsrq(struct net_device *dev,
 113                                        struct ipoib_cm_rx *rx,
 114                                        struct ib_recv_wr *wr,
 115                                        struct ib_sge *sge, int id)
 116{
 117        struct ipoib_dev_priv *priv = netdev_priv(dev);
 118        struct ib_recv_wr *bad_wr;
 119        int i, ret;
 120
 121        wr->wr_id = id | IPOIB_OP_CM | IPOIB_OP_RECV;
 122
 123        for (i = 0; i < IPOIB_CM_RX_SG; ++i)
 124                sge[i].addr = rx->rx_ring[id].mapping[i];
 125
 126        ret = ib_post_recv(rx->qp, wr, &bad_wr);
 127        if (unlikely(ret)) {
 128                ipoib_warn(priv, "post recv failed for buf %d (%d)\n", id, ret);
 129                ipoib_cm_dma_unmap_rx(priv, IPOIB_CM_RX_SG - 1,
 130                                      rx->rx_ring[id].mapping);
 131                dev_kfree_skb_any(rx->rx_ring[id].skb);
 132                rx->rx_ring[id].skb = NULL;
 133        }
 134
 135        return ret;
 136}
 137
 138static struct sk_buff *ipoib_cm_alloc_rx_skb(struct net_device *dev,
 139                                             struct ipoib_cm_rx_buf *rx_ring,
 140                                             int id, int frags,
 141                                             u64 mapping[IPOIB_CM_RX_SG])
 142{
 143        struct ipoib_dev_priv *priv = netdev_priv(dev);
 144        struct sk_buff *skb;
 145        int i;
 146
 147        skb = dev_alloc_skb(IPOIB_CM_HEAD_SIZE + 12);
 148        if (unlikely(!skb))
 149                return NULL;
 150
 151        /*
 152         * IPoIB adds a 4 byte header. So we need 12 more bytes to align the
 153         * IP header to a multiple of 16.
 154         */
 155        skb_reserve(skb, 12);
 156
 157        mapping[0] = ib_dma_map_single(priv->ca, skb->data, IPOIB_CM_HEAD_SIZE,
 158                                       DMA_FROM_DEVICE);
 159        if (unlikely(ib_dma_mapping_error(priv->ca, mapping[0]))) {
 160                dev_kfree_skb_any(skb);
 161                return NULL;
 162        }
 163
 164        for (i = 0; i < frags; i++) {
 165                struct page *page = alloc_page(GFP_ATOMIC);
 166
 167                if (!page)
 168                        goto partial_error;
 169                skb_fill_page_desc(skb, i, page, 0, PAGE_SIZE);
 170
 171                mapping[i + 1] = ib_dma_map_page(priv->ca, skb_shinfo(skb)->frags[i].page,
 172                                                 0, PAGE_SIZE, DMA_FROM_DEVICE);
 173                if (unlikely(ib_dma_mapping_error(priv->ca, mapping[i + 1])))
 174                        goto partial_error;
 175        }
 176
 177        rx_ring[id].skb = skb;
 178        return skb;
 179
 180partial_error:
 181
 182        ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_CM_HEAD_SIZE, DMA_FROM_DEVICE);
 183
 184        for (; i > 0; --i)
 185                ib_dma_unmap_single(priv->ca, mapping[i], PAGE_SIZE, DMA_FROM_DEVICE);
 186
 187        dev_kfree_skb_any(skb);
 188        return NULL;
 189}
 190
 191static void ipoib_cm_free_rx_ring(struct net_device *dev,
 192                                  struct ipoib_cm_rx_buf *rx_ring)
 193{
 194        struct ipoib_dev_priv *priv = netdev_priv(dev);
 195        int i;
 196
 197        for (i = 0; i < ipoib_recvq_size; ++i)
 198                if (rx_ring[i].skb) {
 199                        ipoib_cm_dma_unmap_rx(priv, IPOIB_CM_RX_SG - 1,
 200                                              rx_ring[i].mapping);
 201                        dev_kfree_skb_any(rx_ring[i].skb);
 202                }
 203
 204        vfree(rx_ring);
 205}
 206
 207static void ipoib_cm_start_rx_drain(struct ipoib_dev_priv *priv)
 208{
 209        struct ib_send_wr *bad_wr;
 210        struct ipoib_cm_rx *p;
 211
 212        /* We only reserved 1 extra slot in CQ for drain WRs, so
 213         * make sure we have at most 1 outstanding WR. */
 214        if (list_empty(&priv->cm.rx_flush_list) ||
 215            !list_empty(&priv->cm.rx_drain_list))
 216                return;
 217
 218        /*
 219         * QPs on flush list are error state.  This way, a "flush
 220         * error" WC will be immediately generated for each WR we post.
 221         */
 222        p = list_entry(priv->cm.rx_flush_list.next, typeof(*p), list);
 223        if (ib_post_send(p->qp, &ipoib_cm_rx_drain_wr, &bad_wr))
 224                ipoib_warn(priv, "failed to post drain wr\n");
 225
 226        list_splice_init(&priv->cm.rx_flush_list, &priv->cm.rx_drain_list);
 227}
 228
 229static void ipoib_cm_rx_event_handler(struct ib_event *event, void *ctx)
 230{
 231        struct ipoib_cm_rx *p = ctx;
 232        struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 233        unsigned long flags;
 234
 235        if (event->event != IB_EVENT_QP_LAST_WQE_REACHED)
 236                return;
 237
 238        spin_lock_irqsave(&priv->lock, flags);
 239        list_move(&p->list, &priv->cm.rx_flush_list);
 240        p->state = IPOIB_CM_RX_FLUSH;
 241        ipoib_cm_start_rx_drain(priv);
 242        spin_unlock_irqrestore(&priv->lock, flags);
 243}
 244
 245static struct ib_qp *ipoib_cm_create_rx_qp(struct net_device *dev,
 246                                           struct ipoib_cm_rx *p)
 247{
 248        struct ipoib_dev_priv *priv = netdev_priv(dev);
 249        struct ib_qp_init_attr attr = {
 250                .event_handler = ipoib_cm_rx_event_handler,
 251                .send_cq = priv->recv_cq, /* For drain WR */
 252                .recv_cq = priv->recv_cq,
 253                .srq = priv->cm.srq,
 254                .cap.max_send_wr = 1, /* For drain WR */
 255                .cap.max_send_sge = 1, /* FIXME: 0 Seems not to work */
 256                .sq_sig_type = IB_SIGNAL_ALL_WR,
 257                .qp_type = IB_QPT_RC,
 258                .qp_context = p,
 259        };
 260
 261        if (!ipoib_cm_has_srq(dev)) {
 262                attr.cap.max_recv_wr  = ipoib_recvq_size;
 263                attr.cap.max_recv_sge = IPOIB_CM_RX_SG;
 264        }
 265
 266        return ib_create_qp(priv->pd, &attr);
 267}
 268
 269static int ipoib_cm_modify_rx_qp(struct net_device *dev,
 270                                 struct ib_cm_id *cm_id, struct ib_qp *qp,
 271                                 unsigned psn)
 272{
 273        struct ipoib_dev_priv *priv = netdev_priv(dev);
 274        struct ib_qp_attr qp_attr;
 275        int qp_attr_mask, ret;
 276
 277        qp_attr.qp_state = IB_QPS_INIT;
 278        ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 279        if (ret) {
 280                ipoib_warn(priv, "failed to init QP attr for INIT: %d\n", ret);
 281                return ret;
 282        }
 283        ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
 284        if (ret) {
 285                ipoib_warn(priv, "failed to modify QP to INIT: %d\n", ret);
 286                return ret;
 287        }
 288        qp_attr.qp_state = IB_QPS_RTR;
 289        ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 290        if (ret) {
 291                ipoib_warn(priv, "failed to init QP attr for RTR: %d\n", ret);
 292                return ret;
 293        }
 294        qp_attr.rq_psn = psn;
 295        ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
 296        if (ret) {
 297                ipoib_warn(priv, "failed to modify QP to RTR: %d\n", ret);
 298                return ret;
 299        }
 300
 301        /*
 302         * Current Mellanox HCA firmware won't generate completions
 303         * with error for drain WRs unless the QP has been moved to
 304         * RTS first. This work-around leaves a window where a QP has
 305         * moved to error asynchronously, but this will eventually get
 306         * fixed in firmware, so let's not error out if modify QP
 307         * fails.
 308         */
 309        qp_attr.qp_state = IB_QPS_RTS;
 310        ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 311        if (ret) {
 312                ipoib_warn(priv, "failed to init QP attr for RTS: %d\n", ret);
 313                return 0;
 314        }
 315        ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
 316        if (ret) {
 317                ipoib_warn(priv, "failed to modify QP to RTS: %d\n", ret);
 318                return 0;
 319        }
 320
 321        return 0;
 322}
 323
 324static void ipoib_cm_init_rx_wr(struct net_device *dev,
 325                                struct ib_recv_wr *wr,
 326                                struct ib_sge *sge)
 327{
 328        struct ipoib_dev_priv *priv = netdev_priv(dev);
 329        int i;
 330
 331        for (i = 0; i < priv->cm.num_frags; ++i)
 332                sge[i].lkey = priv->mr->lkey;
 333
 334        sge[0].length = IPOIB_CM_HEAD_SIZE;
 335        for (i = 1; i < priv->cm.num_frags; ++i)
 336                sge[i].length = PAGE_SIZE;
 337
 338        wr->next    = NULL;
 339        wr->sg_list = sge;
 340        wr->num_sge = priv->cm.num_frags;
 341}
 342
 343static int ipoib_cm_nonsrq_init_rx(struct net_device *dev, struct ib_cm_id *cm_id,
 344                                   struct ipoib_cm_rx *rx)
 345{
 346        struct ipoib_dev_priv *priv = netdev_priv(dev);
 347        struct {
 348                struct ib_recv_wr wr;
 349                struct ib_sge sge[IPOIB_CM_RX_SG];
 350        } *t;
 351        int ret;
 352        int i;
 353
 354        rx->rx_ring = vmalloc(ipoib_recvq_size * sizeof *rx->rx_ring);
 355        if (!rx->rx_ring) {
 356                printk(KERN_WARNING "%s: failed to allocate CM non-SRQ ring (%d entries)\n",
 357                       priv->ca->name, ipoib_recvq_size);
 358                return -ENOMEM;
 359        }
 360
 361        memset(rx->rx_ring, 0, ipoib_recvq_size * sizeof *rx->rx_ring);
 362
 363        t = kmalloc(sizeof *t, GFP_KERNEL);
 364        if (!t) {
 365                ret = -ENOMEM;
 366                goto err_free;
 367        }
 368
 369        ipoib_cm_init_rx_wr(dev, &t->wr, t->sge);
 370
 371        spin_lock_irq(&priv->lock);
 372
 373        if (priv->cm.nonsrq_conn_qp >= ipoib_max_conn_qp) {
 374                spin_unlock_irq(&priv->lock);
 375                ib_send_cm_rej(cm_id, IB_CM_REJ_NO_QP, NULL, 0, NULL, 0);
 376                ret = -EINVAL;
 377                goto err_free;
 378        } else
 379                ++priv->cm.nonsrq_conn_qp;
 380
 381        spin_unlock_irq(&priv->lock);
 382
 383        for (i = 0; i < ipoib_recvq_size; ++i) {
 384                if (!ipoib_cm_alloc_rx_skb(dev, rx->rx_ring, i, IPOIB_CM_RX_SG - 1,
 385                                           rx->rx_ring[i].mapping)) {
 386                        ipoib_warn(priv, "failed to allocate receive buffer %d\n", i);
 387                                ret = -ENOMEM;
 388                                goto err_count;
 389                }
 390                ret = ipoib_cm_post_receive_nonsrq(dev, rx, &t->wr, t->sge, i);
 391                if (ret) {
 392                        ipoib_warn(priv, "ipoib_cm_post_receive_nonsrq "
 393                                   "failed for buf %d\n", i);
 394                        ret = -EIO;
 395                        goto err_count;
 396                }
 397        }
 398
 399        rx->recv_count = ipoib_recvq_size;
 400
 401        kfree(t);
 402
 403        return 0;
 404
 405err_count:
 406        spin_lock_irq(&priv->lock);
 407        --priv->cm.nonsrq_conn_qp;
 408        spin_unlock_irq(&priv->lock);
 409
 410err_free:
 411        kfree(t);
 412        ipoib_cm_free_rx_ring(dev, rx->rx_ring);
 413
 414        return ret;
 415}
 416
 417static int ipoib_cm_send_rep(struct net_device *dev, struct ib_cm_id *cm_id,
 418                             struct ib_qp *qp, struct ib_cm_req_event_param *req,
 419                             unsigned psn)
 420{
 421        struct ipoib_dev_priv *priv = netdev_priv(dev);
 422        struct ipoib_cm_data data = {};
 423        struct ib_cm_rep_param rep = {};
 424
 425        data.qpn = cpu_to_be32(priv->qp->qp_num);
 426        data.mtu = cpu_to_be32(IPOIB_CM_BUF_SIZE);
 427
 428        rep.private_data = &data;
 429        rep.private_data_len = sizeof data;
 430        rep.flow_control = 0;
 431        rep.rnr_retry_count = req->rnr_retry_count;
 432        rep.srq = ipoib_cm_has_srq(dev);
 433        rep.qp_num = qp->qp_num;
 434        rep.starting_psn = psn;
 435        return ib_send_cm_rep(cm_id, &rep);
 436}
 437
 438static int ipoib_cm_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 439{
 440        struct net_device *dev = cm_id->context;
 441        struct ipoib_dev_priv *priv = netdev_priv(dev);
 442        struct ipoib_cm_rx *p;
 443        unsigned psn;
 444        int ret;
 445
 446        ipoib_dbg(priv, "REQ arrived\n");
 447        p = kzalloc(sizeof *p, GFP_KERNEL);
 448        if (!p)
 449                return -ENOMEM;
 450        p->dev = dev;
 451        p->id = cm_id;
 452        cm_id->context = p;
 453        p->state = IPOIB_CM_RX_LIVE;
 454        p->jiffies = jiffies;
 455        INIT_LIST_HEAD(&p->list);
 456
 457        p->qp = ipoib_cm_create_rx_qp(dev, p);
 458        if (IS_ERR(p->qp)) {
 459                ret = PTR_ERR(p->qp);
 460                goto err_qp;
 461        }
 462
 463        psn = random32() & 0xffffff;
 464        ret = ipoib_cm_modify_rx_qp(dev, cm_id, p->qp, psn);
 465        if (ret)
 466                goto err_modify;
 467
 468        if (!ipoib_cm_has_srq(dev)) {
 469                ret = ipoib_cm_nonsrq_init_rx(dev, cm_id, p);
 470                if (ret)
 471                        goto err_modify;
 472        }
 473
 474        spin_lock_irq(&priv->lock);
 475        queue_delayed_work(ipoib_workqueue,
 476                           &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
 477        /* Add this entry to passive ids list head, but do not re-add it
 478         * if IB_EVENT_QP_LAST_WQE_REACHED has moved it to flush list. */
 479        p->jiffies = jiffies;
 480        if (p->state == IPOIB_CM_RX_LIVE)
 481                list_move(&p->list, &priv->cm.passive_ids);
 482        spin_unlock_irq(&priv->lock);
 483
 484        ret = ipoib_cm_send_rep(dev, cm_id, p->qp, &event->param.req_rcvd, psn);
 485        if (ret) {
 486                ipoib_warn(priv, "failed to send REP: %d\n", ret);
 487                if (ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE))
 488                        ipoib_warn(priv, "unable to move qp to error state\n");
 489        }
 490        return 0;
 491
 492err_modify:
 493        ib_destroy_qp(p->qp);
 494err_qp:
 495        kfree(p);
 496        return ret;
 497}
 498
 499static int ipoib_cm_rx_handler(struct ib_cm_id *cm_id,
 500                               struct ib_cm_event *event)
 501{
 502        struct ipoib_cm_rx *p;
 503        struct ipoib_dev_priv *priv;
 504
 505        switch (event->event) {
 506        case IB_CM_REQ_RECEIVED:
 507                return ipoib_cm_req_handler(cm_id, event);
 508        case IB_CM_DREQ_RECEIVED:
 509                p = cm_id->context;
 510                ib_send_cm_drep(cm_id, NULL, 0);
 511                /* Fall through */
 512        case IB_CM_REJ_RECEIVED:
 513                p = cm_id->context;
 514                priv = netdev_priv(p->dev);
 515                if (ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE))
 516                        ipoib_warn(priv, "unable to move qp to error state\n");
 517                /* Fall through */
 518        default:
 519                return 0;
 520        }
 521}
 522/* Adjust length of skb with fragments to match received data */
 523static void skb_put_frags(struct sk_buff *skb, unsigned int hdr_space,
 524                          unsigned int length, struct sk_buff *toskb)
 525{
 526        int i, num_frags;
 527        unsigned int size;
 528
 529        /* put header into skb */
 530        size = min(length, hdr_space);
 531        skb->tail += size;
 532        skb->len += size;
 533        length -= size;
 534
 535        num_frags = skb_shinfo(skb)->nr_frags;
 536        for (i = 0; i < num_frags; i++) {
 537                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 538
 539                if (length == 0) {
 540                        /* don't need this page */
 541                        skb_fill_page_desc(toskb, i, frag->page, 0, PAGE_SIZE);
 542                        --skb_shinfo(skb)->nr_frags;
 543                } else {
 544                        size = min(length, (unsigned) PAGE_SIZE);
 545
 546                        frag->size = size;
 547                        skb->data_len += size;
 548                        skb->truesize += size;
 549                        skb->len += size;
 550                        length -= size;
 551                }
 552        }
 553}
 554
 555void ipoib_cm_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
 556{
 557        struct ipoib_dev_priv *priv = netdev_priv(dev);
 558        struct ipoib_cm_rx_buf *rx_ring;
 559        unsigned int wr_id = wc->wr_id & ~(IPOIB_OP_CM | IPOIB_OP_RECV);
 560        struct sk_buff *skb, *newskb;
 561        struct ipoib_cm_rx *p;
 562        unsigned long flags;
 563        u64 mapping[IPOIB_CM_RX_SG];
 564        int frags;
 565        int has_srq;
 566        struct sk_buff *small_skb;
 567
 568        ipoib_dbg_data(priv, "cm recv completion: id %d, status: %d\n",
 569                       wr_id, wc->status);
 570
 571        if (unlikely(wr_id >= ipoib_recvq_size)) {
 572                if (wr_id == (IPOIB_CM_RX_DRAIN_WRID & ~(IPOIB_OP_CM | IPOIB_OP_RECV))) {
 573                        spin_lock_irqsave(&priv->lock, flags);
 574                        list_splice_init(&priv->cm.rx_drain_list, &priv->cm.rx_reap_list);
 575                        ipoib_cm_start_rx_drain(priv);
 576                        queue_work(ipoib_workqueue, &priv->cm.rx_reap_task);
 577                        spin_unlock_irqrestore(&priv->lock, flags);
 578                } else
 579                        ipoib_warn(priv, "cm recv completion event with wrid %d (> %d)\n",
 580                                   wr_id, ipoib_recvq_size);
 581                return;
 582        }
 583
 584        p = wc->qp->qp_context;
 585
 586        has_srq = ipoib_cm_has_srq(dev);
 587        rx_ring = has_srq ? priv->cm.srq_ring : p->rx_ring;
 588
 589        skb = rx_ring[wr_id].skb;
 590
 591        if (unlikely(wc->status != IB_WC_SUCCESS)) {
 592                ipoib_dbg(priv, "cm recv error "
 593                           "(status=%d, wrid=%d vend_err %x)\n",
 594                           wc->status, wr_id, wc->vendor_err);
 595                ++dev->stats.rx_dropped;
 596                if (has_srq)
 597                        goto repost;
 598                else {
 599                        if (!--p->recv_count) {
 600                                spin_lock_irqsave(&priv->lock, flags);
 601                                list_move(&p->list, &priv->cm.rx_reap_list);
 602                                spin_unlock_irqrestore(&priv->lock, flags);
 603                                queue_work(ipoib_workqueue, &priv->cm.rx_reap_task);
 604                        }
 605                        return;
 606                }
 607        }
 608
 609        if (unlikely(!(wr_id & IPOIB_CM_RX_UPDATE_MASK))) {
 610                if (p && time_after_eq(jiffies, p->jiffies + IPOIB_CM_RX_UPDATE_TIME)) {
 611                        spin_lock_irqsave(&priv->lock, flags);
 612                        p->jiffies = jiffies;
 613                        /* Move this entry to list head, but do not re-add it
 614                         * if it has been moved out of list. */
 615                        if (p->state == IPOIB_CM_RX_LIVE)
 616                                list_move(&p->list, &priv->cm.passive_ids);
 617                        spin_unlock_irqrestore(&priv->lock, flags);
 618                }
 619        }
 620
 621        if (wc->byte_len < IPOIB_CM_COPYBREAK) {
 622                int dlen = wc->byte_len;
 623
 624                small_skb = dev_alloc_skb(dlen + 12);
 625                if (small_skb) {
 626                        skb_reserve(small_skb, 12);
 627                        ib_dma_sync_single_for_cpu(priv->ca, rx_ring[wr_id].mapping[0],
 628                                                   dlen, DMA_FROM_DEVICE);
 629                        skb_copy_from_linear_data(skb, small_skb->data, dlen);
 630                        ib_dma_sync_single_for_device(priv->ca, rx_ring[wr_id].mapping[0],
 631                                                      dlen, DMA_FROM_DEVICE);
 632                        skb_put(small_skb, dlen);
 633                        skb = small_skb;
 634                        goto copied;
 635                }
 636        }
 637
 638        frags = PAGE_ALIGN(wc->byte_len - min(wc->byte_len,
 639                                              (unsigned)IPOIB_CM_HEAD_SIZE)) / PAGE_SIZE;
 640
 641        newskb = ipoib_cm_alloc_rx_skb(dev, rx_ring, wr_id, frags, mapping);
 642        if (unlikely(!newskb)) {
 643                /*
 644                 * If we can't allocate a new RX buffer, dump
 645                 * this packet and reuse the old buffer.
 646                 */
 647                ipoib_dbg(priv, "failed to allocate receive buffer %d\n", wr_id);
 648                ++dev->stats.rx_dropped;
 649                goto repost;
 650        }
 651
 652        ipoib_cm_dma_unmap_rx(priv, frags, rx_ring[wr_id].mapping);
 653        memcpy(rx_ring[wr_id].mapping, mapping, (frags + 1) * sizeof *mapping);
 654
 655        ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n",
 656                       wc->byte_len, wc->slid);
 657
 658        skb_put_frags(skb, IPOIB_CM_HEAD_SIZE, wc->byte_len, newskb);
 659
 660copied:
 661        skb->protocol = ((struct ipoib_header *) skb->data)->proto;
 662        skb_reset_mac_header(skb);
 663        skb_pull(skb, IPOIB_ENCAP_LEN);
 664
 665        ++dev->stats.rx_packets;
 666        dev->stats.rx_bytes += skb->len;
 667
 668        skb->dev = dev;
 669        /* XXX get correct PACKET_ type here */
 670        skb->pkt_type = PACKET_HOST;
 671        netif_receive_skb(skb);
 672
 673repost:
 674        if (has_srq) {
 675                if (unlikely(ipoib_cm_post_receive_srq(dev, wr_id)))
 676                        ipoib_warn(priv, "ipoib_cm_post_receive_srq failed "
 677                                   "for buf %d\n", wr_id);
 678        } else {
 679                if (unlikely(ipoib_cm_post_receive_nonsrq(dev, p,
 680                                                          &priv->cm.rx_wr,
 681                                                          priv->cm.rx_sge,
 682                                                          wr_id))) {
 683                        --p->recv_count;
 684                        ipoib_warn(priv, "ipoib_cm_post_receive_nonsrq failed "
 685                                   "for buf %d\n", wr_id);
 686                }
 687        }
 688}
 689
 690static inline int post_send(struct ipoib_dev_priv *priv,
 691                            struct ipoib_cm_tx *tx,
 692                            unsigned int wr_id,
 693                            u64 addr, int len)
 694{
 695        struct ib_send_wr *bad_wr;
 696
 697        priv->tx_sge[0].addr          = addr;
 698        priv->tx_sge[0].length        = len;
 699
 700        priv->tx_wr.num_sge     = 1;
 701        priv->tx_wr.wr_id       = wr_id | IPOIB_OP_CM;
 702
 703        return ib_post_send(tx->qp, &priv->tx_wr, &bad_wr);
 704}
 705
 706void ipoib_cm_send(struct net_device *dev, struct sk_buff *skb, struct ipoib_cm_tx *tx)
 707{
 708        struct ipoib_dev_priv *priv = netdev_priv(dev);
 709        struct ipoib_cm_tx_buf *tx_req;
 710        u64 addr;
 711
 712        if (unlikely(skb->len > tx->mtu)) {
 713                ipoib_warn(priv, "packet len %d (> %d) too long to send, dropping\n",
 714                           skb->len, tx->mtu);
 715                ++dev->stats.tx_dropped;
 716                ++dev->stats.tx_errors;
 717                ipoib_cm_skb_too_long(dev, skb, tx->mtu - IPOIB_ENCAP_LEN);
 718                return;
 719        }
 720
 721        ipoib_dbg_data(priv, "sending packet: head 0x%x length %d connection 0x%x\n",
 722                       tx->tx_head, skb->len, tx->qp->qp_num);
 723
 724        /*
 725         * We put the skb into the tx_ring _before_ we call post_send()
 726         * because it's entirely possible that the completion handler will
 727         * run before we execute anything after the post_send().  That
 728         * means we have to make sure everything is properly recorded and
 729         * our state is consistent before we call post_send().
 730         */
 731        tx_req = &tx->tx_ring[tx->tx_head & (ipoib_sendq_size - 1)];
 732        tx_req->skb = skb;
 733        addr = ib_dma_map_single(priv->ca, skb->data, skb->len, DMA_TO_DEVICE);
 734        if (unlikely(ib_dma_mapping_error(priv->ca, addr))) {
 735                ++dev->stats.tx_errors;
 736                dev_kfree_skb_any(skb);
 737                return;
 738        }
 739
 740        tx_req->mapping = addr;
 741
 742        if (unlikely(post_send(priv, tx, tx->tx_head & (ipoib_sendq_size - 1),
 743                               addr, skb->len))) {
 744                ipoib_warn(priv, "post_send failed\n");
 745                ++dev->stats.tx_errors;
 746                ib_dma_unmap_single(priv->ca, addr, skb->len, DMA_TO_DEVICE);
 747                dev_kfree_skb_any(skb);
 748        } else {
 749                dev->trans_start = jiffies;
 750                ++tx->tx_head;
 751
 752                if (++priv->tx_outstanding == ipoib_sendq_size) {
 753                        ipoib_dbg(priv, "TX ring 0x%x full, stopping kernel net queue\n",
 754                                  tx->qp->qp_num);
 755                        netif_stop_queue(dev);
 756                }
 757        }
 758}
 759
 760void ipoib_cm_handle_tx_wc(struct net_device *dev, struct ib_wc *wc)
 761{
 762        struct ipoib_dev_priv *priv = netdev_priv(dev);
 763        struct ipoib_cm_tx *tx = wc->qp->qp_context;
 764        unsigned int wr_id = wc->wr_id & ~IPOIB_OP_CM;
 765        struct ipoib_cm_tx_buf *tx_req;
 766        unsigned long flags;
 767
 768        ipoib_dbg_data(priv, "cm send completion: id %d, status: %d\n",
 769                       wr_id, wc->status);
 770
 771        if (unlikely(wr_id >= ipoib_sendq_size)) {
 772                ipoib_warn(priv, "cm send completion event with wrid %d (> %d)\n",
 773                           wr_id, ipoib_sendq_size);
 774                return;
 775        }
 776
 777        tx_req = &tx->tx_ring[wr_id];
 778
 779        ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len, DMA_TO_DEVICE);
 780
 781        /* FIXME: is this right? Shouldn't we only increment on success? */
 782        ++dev->stats.tx_packets;
 783        dev->stats.tx_bytes += tx_req->skb->len;
 784
 785        dev_kfree_skb_any(tx_req->skb);
 786
 787        netif_tx_lock(dev);
 788
 789        ++tx->tx_tail;
 790        if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
 791            netif_queue_stopped(dev) &&
 792            test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
 793                netif_wake_queue(dev);
 794
 795        if (wc->status != IB_WC_SUCCESS &&
 796            wc->status != IB_WC_WR_FLUSH_ERR) {
 797                struct ipoib_neigh *neigh;
 798
 799                ipoib_dbg(priv, "failed cm send event "
 800                           "(status=%d, wrid=%d vend_err %x)\n",
 801                           wc->status, wr_id, wc->vendor_err);
 802
 803                spin_lock_irqsave(&priv->lock, flags);
 804                neigh = tx->neigh;
 805
 806                if (neigh) {
 807                        neigh->cm = NULL;
 808                        list_del(&neigh->list);
 809                        if (neigh->ah)
 810                                ipoib_put_ah(neigh->ah);
 811                        ipoib_neigh_free(dev, neigh);
 812
 813                        tx->neigh = NULL;
 814                }
 815
 816                if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
 817                        list_move(&tx->list, &priv->cm.reap_list);
 818                        queue_work(ipoib_workqueue, &priv->cm.reap_task);
 819                }
 820
 821                clear_bit(IPOIB_FLAG_OPER_UP, &tx->flags);
 822
 823                spin_unlock_irqrestore(&priv->lock, flags);
 824        }
 825
 826        netif_tx_unlock(dev);
 827}
 828
 829int ipoib_cm_dev_open(struct net_device *dev)
 830{
 831        struct ipoib_dev_priv *priv = netdev_priv(dev);
 832        int ret;
 833
 834        if (!IPOIB_CM_SUPPORTED(dev->dev_addr))
 835                return 0;
 836
 837        priv->cm.id = ib_create_cm_id(priv->ca, ipoib_cm_rx_handler, dev);
 838        if (IS_ERR(priv->cm.id)) {
 839                printk(KERN_WARNING "%s: failed to create CM ID\n", priv->ca->name);
 840                ret = PTR_ERR(priv->cm.id);
 841                goto err_cm;
 842        }
 843
 844        ret = ib_cm_listen(priv->cm.id, cpu_to_be64(IPOIB_CM_IETF_ID | priv->qp->qp_num),
 845                           0, NULL);
 846        if (ret) {
 847                printk(KERN_WARNING "%s: failed to listen on ID 0x%llx\n", priv->ca->name,
 848                       IPOIB_CM_IETF_ID | priv->qp->qp_num);
 849                goto err_listen;
 850        }
 851
 852        return 0;
 853
 854err_listen:
 855        ib_destroy_cm_id(priv->cm.id);
 856err_cm:
 857        priv->cm.id = NULL;
 858        return ret;
 859}
 860
 861static void ipoib_cm_free_rx_reap_list(struct net_device *dev)
 862{
 863        struct ipoib_dev_priv *priv = netdev_priv(dev);
 864        struct ipoib_cm_rx *rx, *n;
 865        LIST_HEAD(list);
 866
 867        spin_lock_irq(&priv->lock);
 868        list_splice_init(&priv->cm.rx_reap_list, &list);
 869        spin_unlock_irq(&priv->lock);
 870
 871        list_for_each_entry_safe(rx, n, &list, list) {
 872                ib_destroy_cm_id(rx->id);
 873                ib_destroy_qp(rx->qp);
 874                if (!ipoib_cm_has_srq(dev)) {
 875                        ipoib_cm_free_rx_ring(priv->dev, rx->rx_ring);
 876                        spin_lock_irq(&priv->lock);
 877                        --priv->cm.nonsrq_conn_qp;
 878                        spin_unlock_irq(&priv->lock);
 879                }
 880                kfree(rx);
 881        }
 882}
 883
 884void ipoib_cm_dev_stop(struct net_device *dev)
 885{
 886        struct ipoib_dev_priv *priv = netdev_priv(dev);
 887        struct ipoib_cm_rx *p;
 888        unsigned long begin;
 889        int ret;
 890
 891        if (!IPOIB_CM_SUPPORTED(dev->dev_addr) || !priv->cm.id)
 892                return;
 893
 894        ib_destroy_cm_id(priv->cm.id);
 895        priv->cm.id = NULL;
 896
 897        spin_lock_irq(&priv->lock);
 898        while (!list_empty(&priv->cm.passive_ids)) {
 899                p = list_entry(priv->cm.passive_ids.next, typeof(*p), list);
 900                list_move(&p->list, &priv->cm.rx_error_list);
 901                p->state = IPOIB_CM_RX_ERROR;
 902                spin_unlock_irq(&priv->lock);
 903                ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
 904                if (ret)
 905                        ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
 906                spin_lock_irq(&priv->lock);
 907        }
 908
 909        /* Wait for all RX to be drained */
 910        begin = jiffies;
 911
 912        while (!list_empty(&priv->cm.rx_error_list) ||
 913               !list_empty(&priv->cm.rx_flush_list) ||
 914               !list_empty(&priv->cm.rx_drain_list)) {
 915                if (time_after(jiffies, begin + 5 * HZ)) {
 916                        ipoib_warn(priv, "RX drain timing out\n");
 917
 918                        /*
 919                         * assume the HW is wedged and just free up everything.
 920                         */
 921                        list_splice_init(&priv->cm.rx_flush_list,
 922                                         &priv->cm.rx_reap_list);
 923                        list_splice_init(&priv->cm.rx_error_list,
 924                                         &priv->cm.rx_reap_list);
 925                        list_splice_init(&priv->cm.rx_drain_list,
 926                                         &priv->cm.rx_reap_list);
 927                        break;
 928                }
 929                spin_unlock_irq(&priv->lock);
 930                msleep(1);
 931                ipoib_drain_cq(dev);
 932                spin_lock_irq(&priv->lock);
 933        }
 934
 935        spin_unlock_irq(&priv->lock);
 936
 937        ipoib_cm_free_rx_reap_list(dev);
 938
 939        cancel_delayed_work(&priv->cm.stale_task);
 940}
 941
 942static int ipoib_cm_rep_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 943{
 944        struct ipoib_cm_tx *p = cm_id->context;
 945        struct ipoib_dev_priv *priv = netdev_priv(p->dev);
 946        struct ipoib_cm_data *data = event->private_data;
 947        struct sk_buff_head skqueue;
 948        struct ib_qp_attr qp_attr;
 949        int qp_attr_mask, ret;
 950        struct sk_buff *skb;
 951
 952        p->mtu = be32_to_cpu(data->mtu);
 953
 954        if (p->mtu <= IPOIB_ENCAP_LEN) {
 955                ipoib_warn(priv, "Rejecting connection: mtu %d <= %d\n",
 956                           p->mtu, IPOIB_ENCAP_LEN);
 957                return -EINVAL;
 958        }
 959
 960        qp_attr.qp_state = IB_QPS_RTR;
 961        ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 962        if (ret) {
 963                ipoib_warn(priv, "failed to init QP attr for RTR: %d\n", ret);
 964                return ret;
 965        }
 966
 967        qp_attr.rq_psn = 0 /* FIXME */;
 968        ret = ib_modify_qp(p->qp, &qp_attr, qp_attr_mask);
 969        if (ret) {
 970                ipoib_warn(priv, "failed to modify QP to RTR: %d\n", ret);
 971                return ret;
 972        }
 973
 974        qp_attr.qp_state = IB_QPS_RTS;
 975        ret = ib_cm_init_qp_attr(cm_id, &qp_attr, &qp_attr_mask);
 976        if (ret) {
 977                ipoib_warn(priv, "failed to init QP attr for RTS: %d\n", ret);
 978                return ret;
 979        }
 980        ret = ib_modify_qp(p->qp, &qp_attr, qp_attr_mask);
 981        if (ret) {
 982                ipoib_warn(priv, "failed to modify QP to RTS: %d\n", ret);
 983                return ret;
 984        }
 985
 986        skb_queue_head_init(&skqueue);
 987
 988        spin_lock_irq(&priv->lock);
 989        set_bit(IPOIB_FLAG_OPER_UP, &p->flags);
 990        if (p->neigh)
 991                while ((skb = __skb_dequeue(&p->neigh->queue)))
 992                        __skb_queue_tail(&skqueue, skb);
 993        spin_unlock_irq(&priv->lock);
 994
 995        while ((skb = __skb_dequeue(&skqueue))) {
 996                skb->dev = p->dev;
 997                if (dev_queue_xmit(skb))
 998                        ipoib_warn(priv, "dev_queue_xmit failed "
 999                                   "to requeue packet\n");
1000        }
1001
1002        ret = ib_send_cm_rtu(cm_id, NULL, 0);
1003        if (ret) {
1004                ipoib_warn(priv, "failed to send RTU: %d\n", ret);
1005                return ret;
1006        }
1007        return 0;
1008}
1009
1010static struct ib_qp *ipoib_cm_create_tx_qp(struct net_device *dev, struct ipoib_cm_tx *tx)
1011{
1012        struct ipoib_dev_priv *priv = netdev_priv(dev);
1013        struct ib_qp_init_attr attr = {
1014                .send_cq                = priv->recv_cq,
1015                .recv_cq                = priv->recv_cq,
1016                .srq                    = priv->cm.srq,
1017                .cap.max_send_wr        = ipoib_sendq_size,
1018                .cap.max_send_sge       = 1,
1019                .sq_sig_type            = IB_SIGNAL_ALL_WR,
1020                .qp_type                = IB_QPT_RC,
1021                .qp_context             = tx
1022        };
1023
1024        return ib_create_qp(priv->pd, &attr);
1025}
1026
1027static int ipoib_cm_send_req(struct net_device *dev,
1028                             struct ib_cm_id *id, struct ib_qp *qp,
1029                             u32 qpn,
1030                             struct ib_sa_path_rec *pathrec)
1031{
1032        struct ipoib_dev_priv *priv = netdev_priv(dev);
1033        struct ipoib_cm_data data = {};
1034        struct ib_cm_req_param req = {};
1035
1036        data.qpn = cpu_to_be32(priv->qp->qp_num);
1037        data.mtu = cpu_to_be32(IPOIB_CM_BUF_SIZE);
1038
1039        req.primary_path                = pathrec;
1040        req.alternate_path              = NULL;
1041        req.service_id                  = cpu_to_be64(IPOIB_CM_IETF_ID | qpn);
1042        req.qp_num                      = qp->qp_num;
1043        req.qp_type                     = qp->qp_type;
1044        req.private_data                = &data;
1045        req.private_data_len            = sizeof data;
1046        req.flow_control                = 0;
1047
1048        req.starting_psn                = 0; /* FIXME */
1049
1050        /*
1051         * Pick some arbitrary defaults here; we could make these
1052         * module parameters if anyone cared about setting them.
1053         */
1054        req.responder_resources         = 4;
1055        req.remote_cm_response_timeout  = 20;
1056        req.local_cm_response_timeout   = 20;
1057        req.retry_count                 = 0; /* RFC draft warns against retries */
1058        req.rnr_retry_count             = 0; /* RFC draft warns against retries */
1059        req.max_cm_retries              = 15;
1060        req.srq                         = ipoib_cm_has_srq(dev);
1061        return ib_send_cm_req(id, &req);
1062}
1063
1064static int ipoib_cm_modify_tx_init(struct net_device *dev,
1065                                  struct ib_cm_id *cm_id, struct ib_qp *qp)
1066{
1067        struct ipoib_dev_priv *priv = netdev_priv(dev);
1068        struct ib_qp_attr qp_attr;
1069        int qp_attr_mask, ret;
1070        ret = ib_find_pkey(priv->ca, priv->port, priv->pkey, &qp_attr.pkey_index);
1071        if (ret) {
1072                ipoib_warn(priv, "pkey 0x%x not found: %d\n", priv->pkey, ret);
1073                return ret;
1074        }
1075
1076        qp_attr.qp_state = IB_QPS_INIT;
1077        qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE;
1078        qp_attr.port_num = priv->port;
1079        qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS | IB_QP_PKEY_INDEX | IB_QP_PORT;
1080
1081        ret = ib_modify_qp(qp, &qp_attr, qp_attr_mask);
1082        if (ret) {
1083                ipoib_warn(priv, "failed to modify tx QP to INIT: %d\n", ret);
1084                return ret;
1085        }
1086        return 0;
1087}
1088
1089static int ipoib_cm_tx_init(struct ipoib_cm_tx *p, u32 qpn,
1090                            struct ib_sa_path_rec *pathrec)
1091{
1092        struct ipoib_dev_priv *priv = netdev_priv(p->dev);
1093        int ret;
1094
1095        p->tx_ring = vmalloc(ipoib_sendq_size * sizeof *p->tx_ring);
1096        if (!p->tx_ring) {
1097                ipoib_warn(priv, "failed to allocate tx ring\n");
1098                ret = -ENOMEM;
1099                goto err_tx;
1100        }
1101        memset(p->tx_ring, 0, ipoib_sendq_size * sizeof *p->tx_ring);
1102
1103        p->qp = ipoib_cm_create_tx_qp(p->dev, p);
1104        if (IS_ERR(p->qp)) {
1105                ret = PTR_ERR(p->qp);
1106                ipoib_warn(priv, "failed to allocate tx qp: %d\n", ret);
1107                goto err_qp;
1108        }
1109
1110        p->id = ib_create_cm_id(priv->ca, ipoib_cm_tx_handler, p);
1111        if (IS_ERR(p->id)) {
1112                ret = PTR_ERR(p->id);
1113                ipoib_warn(priv, "failed to create tx cm id: %d\n", ret);
1114                goto err_id;
1115        }
1116
1117        ret = ipoib_cm_modify_tx_init(p->dev, p->id,  p->qp);
1118        if (ret) {
1119                ipoib_warn(priv, "failed to modify tx qp to rtr: %d\n", ret);
1120                goto err_modify;
1121        }
1122
1123        ret = ipoib_cm_send_req(p->dev, p->id, p->qp, qpn, pathrec);
1124        if (ret) {
1125                ipoib_warn(priv, "failed to send cm req: %d\n", ret);
1126                goto err_send_cm;
1127        }
1128
1129        ipoib_dbg(priv, "Request connection 0x%x for gid %pI6 qpn 0x%x\n",
1130                  p->qp->qp_num, pathrec->dgid.raw, qpn);
1131
1132        return 0;
1133
1134err_send_cm:
1135err_modify:
1136        ib_destroy_cm_id(p->id);
1137err_id:
1138        p->id = NULL;
1139        ib_destroy_qp(p->qp);
1140err_qp:
1141        p->qp = NULL;
1142        vfree(p->tx_ring);
1143err_tx:
1144        return ret;
1145}
1146
1147static void ipoib_cm_tx_destroy(struct ipoib_cm_tx *p)
1148{
1149        struct ipoib_dev_priv *priv = netdev_priv(p->dev);
1150        struct ipoib_cm_tx_buf *tx_req;
1151        unsigned long begin;
1152
1153        ipoib_dbg(priv, "Destroy active connection 0x%x head 0x%x tail 0x%x\n",
1154                  p->qp ? p->qp->qp_num : 0, p->tx_head, p->tx_tail);
1155
1156        if (p->id)
1157                ib_destroy_cm_id(p->id);
1158
1159        if (p->tx_ring) {
1160                /* Wait for all sends to complete */
1161                begin = jiffies;
1162                while ((int) p->tx_tail - (int) p->tx_head < 0) {
1163                        if (time_after(jiffies, begin + 5 * HZ)) {
1164                                ipoib_warn(priv, "timing out; %d sends not completed\n",
1165                                           p->tx_head - p->tx_tail);
1166                                goto timeout;
1167                        }
1168
1169                        msleep(1);
1170                }
1171        }
1172
1173timeout:
1174
1175        while ((int) p->tx_tail - (int) p->tx_head < 0) {
1176                tx_req = &p->tx_ring[p->tx_tail & (ipoib_sendq_size - 1)];
1177                ib_dma_unmap_single(priv->ca, tx_req->mapping, tx_req->skb->len,
1178                                    DMA_TO_DEVICE);
1179                dev_kfree_skb_any(tx_req->skb);
1180                ++p->tx_tail;
1181                netif_tx_lock_bh(p->dev);
1182                if (unlikely(--priv->tx_outstanding == ipoib_sendq_size >> 1) &&
1183                    netif_queue_stopped(p->dev) &&
1184                    test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
1185                        netif_wake_queue(p->dev);
1186                netif_tx_unlock_bh(p->dev);
1187        }
1188
1189        if (p->qp)
1190                ib_destroy_qp(p->qp);
1191
1192        vfree(p->tx_ring);
1193        kfree(p);
1194}
1195
1196static int ipoib_cm_tx_handler(struct ib_cm_id *cm_id,
1197                               struct ib_cm_event *event)
1198{
1199        struct ipoib_cm_tx *tx = cm_id->context;
1200        struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
1201        struct net_device *dev = priv->dev;
1202        struct ipoib_neigh *neigh;
1203        unsigned long flags;
1204        int ret;
1205
1206        switch (event->event) {
1207        case IB_CM_DREQ_RECEIVED:
1208                ipoib_dbg(priv, "DREQ received.\n");
1209                ib_send_cm_drep(cm_id, NULL, 0);
1210                break;
1211        case IB_CM_REP_RECEIVED:
1212                ipoib_dbg(priv, "REP received.\n");
1213                ret = ipoib_cm_rep_handler(cm_id, event);
1214                if (ret)
1215                        ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED,
1216                                       NULL, 0, NULL, 0);
1217                break;
1218        case IB_CM_REQ_ERROR:
1219        case IB_CM_REJ_RECEIVED:
1220        case IB_CM_TIMEWAIT_EXIT:
1221                ipoib_dbg(priv, "CM error %d.\n", event->event);
1222                netif_tx_lock_bh(dev);
1223                spin_lock_irqsave(&priv->lock, flags);
1224                neigh = tx->neigh;
1225
1226                if (neigh) {
1227                        neigh->cm = NULL;
1228                        list_del(&neigh->list);
1229                        if (neigh->ah)
1230                                ipoib_put_ah(neigh->ah);
1231                        ipoib_neigh_free(dev, neigh);
1232
1233                        tx->neigh = NULL;
1234                }
1235
1236                if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
1237                        list_move(&tx->list, &priv->cm.reap_list);
1238                        queue_work(ipoib_workqueue, &priv->cm.reap_task);
1239                }
1240
1241                spin_unlock_irqrestore(&priv->lock, flags);
1242                netif_tx_unlock_bh(dev);
1243                break;
1244        default:
1245                break;
1246        }
1247
1248        return 0;
1249}
1250
1251struct ipoib_cm_tx *ipoib_cm_create_tx(struct net_device *dev, struct ipoib_path *path,
1252                                       struct ipoib_neigh *neigh)
1253{
1254        struct ipoib_dev_priv *priv = netdev_priv(dev);
1255        struct ipoib_cm_tx *tx;
1256
1257        tx = kzalloc(sizeof *tx, GFP_ATOMIC);
1258        if (!tx)
1259                return NULL;
1260
1261        neigh->cm = tx;
1262        tx->neigh = neigh;
1263        tx->path = path;
1264        tx->dev = dev;
1265        list_add(&tx->list, &priv->cm.start_list);
1266        set_bit(IPOIB_FLAG_INITIALIZED, &tx->flags);
1267        queue_work(ipoib_workqueue, &priv->cm.start_task);
1268        return tx;
1269}
1270
1271void ipoib_cm_destroy_tx(struct ipoib_cm_tx *tx)
1272{
1273        struct ipoib_dev_priv *priv = netdev_priv(tx->dev);
1274        if (test_and_clear_bit(IPOIB_FLAG_INITIALIZED, &tx->flags)) {
1275                list_move(&tx->list, &priv->cm.reap_list);
1276                queue_work(ipoib_workqueue, &priv->cm.reap_task);
1277                ipoib_dbg(priv, "Reap connection for gid %pI6\n",
1278                          tx->neigh->dgid.raw);
1279                tx->neigh = NULL;
1280        }
1281}
1282
1283static void ipoib_cm_tx_start(struct work_struct *work)
1284{
1285        struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1286                                                   cm.start_task);
1287        struct net_device *dev = priv->dev;
1288        struct ipoib_neigh *neigh;
1289        struct ipoib_cm_tx *p;
1290        unsigned long flags;
1291        int ret;
1292
1293        struct ib_sa_path_rec pathrec;
1294        u32 qpn;
1295
1296        netif_tx_lock_bh(dev);
1297        spin_lock_irqsave(&priv->lock, flags);
1298
1299        while (!list_empty(&priv->cm.start_list)) {
1300                p = list_entry(priv->cm.start_list.next, typeof(*p), list);
1301                list_del_init(&p->list);
1302                neigh = p->neigh;
1303                qpn = IPOIB_QPN(neigh->neighbour->ha);
1304                memcpy(&pathrec, &p->path->pathrec, sizeof pathrec);
1305
1306                spin_unlock_irqrestore(&priv->lock, flags);
1307                netif_tx_unlock_bh(dev);
1308
1309                ret = ipoib_cm_tx_init(p, qpn, &pathrec);
1310
1311                netif_tx_lock_bh(dev);
1312                spin_lock_irqsave(&priv->lock, flags);
1313
1314                if (ret) {
1315                        neigh = p->neigh;
1316                        if (neigh) {
1317                                neigh->cm = NULL;
1318                                list_del(&neigh->list);
1319                                if (neigh->ah)
1320                                        ipoib_put_ah(neigh->ah);
1321                                ipoib_neigh_free(dev, neigh);
1322                        }
1323                        list_del(&p->list);
1324                        kfree(p);
1325                }
1326        }
1327
1328        spin_unlock_irqrestore(&priv->lock, flags);
1329        netif_tx_unlock_bh(dev);
1330}
1331
1332static void ipoib_cm_tx_reap(struct work_struct *work)
1333{
1334        struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1335                                                   cm.reap_task);
1336        struct net_device *dev = priv->dev;
1337        struct ipoib_cm_tx *p;
1338        unsigned long flags;
1339
1340        netif_tx_lock_bh(dev);
1341        spin_lock_irqsave(&priv->lock, flags);
1342
1343        while (!list_empty(&priv->cm.reap_list)) {
1344                p = list_entry(priv->cm.reap_list.next, typeof(*p), list);
1345                list_del(&p->list);
1346                spin_unlock_irqrestore(&priv->lock, flags);
1347                netif_tx_unlock_bh(dev);
1348                ipoib_cm_tx_destroy(p);
1349                netif_tx_lock_bh(dev);
1350                spin_lock_irqsave(&priv->lock, flags);
1351        }
1352
1353        spin_unlock_irqrestore(&priv->lock, flags);
1354        netif_tx_unlock_bh(dev);
1355}
1356
1357static void ipoib_cm_skb_reap(struct work_struct *work)
1358{
1359        struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1360                                                   cm.skb_task);
1361        struct net_device *dev = priv->dev;
1362        struct sk_buff *skb;
1363        unsigned long flags;
1364        unsigned mtu = priv->mcast_mtu;
1365
1366        netif_tx_lock_bh(dev);
1367        spin_lock_irqsave(&priv->lock, flags);
1368
1369        while ((skb = skb_dequeue(&priv->cm.skb_queue))) {
1370                spin_unlock_irqrestore(&priv->lock, flags);
1371                netif_tx_unlock_bh(dev);
1372
1373                if (skb->protocol == htons(ETH_P_IP))
1374                        icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
1375#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1376                else if (skb->protocol == htons(ETH_P_IPV6))
1377                        icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, priv->dev);
1378#endif
1379                dev_kfree_skb_any(skb);
1380
1381                netif_tx_lock_bh(dev);
1382                spin_lock_irqsave(&priv->lock, flags);
1383        }
1384
1385        spin_unlock_irqrestore(&priv->lock, flags);
1386        netif_tx_unlock_bh(dev);
1387}
1388
1389void ipoib_cm_skb_too_long(struct net_device *dev, struct sk_buff *skb,
1390                           unsigned int mtu)
1391{
1392        struct ipoib_dev_priv *priv = netdev_priv(dev);
1393        int e = skb_queue_empty(&priv->cm.skb_queue);
1394
1395        if (skb_dst(skb))
1396                skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
1397
1398        skb_queue_tail(&priv->cm.skb_queue, skb);
1399        if (e)
1400                queue_work(ipoib_workqueue, &priv->cm.skb_task);
1401}
1402
1403static void ipoib_cm_rx_reap(struct work_struct *work)
1404{
1405        ipoib_cm_free_rx_reap_list(container_of(work, struct ipoib_dev_priv,
1406                                                cm.rx_reap_task)->dev);
1407}
1408
1409static void ipoib_cm_stale_task(struct work_struct *work)
1410{
1411        struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
1412                                                   cm.stale_task.work);
1413        struct ipoib_cm_rx *p;
1414        int ret;
1415
1416        spin_lock_irq(&priv->lock);
1417        while (!list_empty(&priv->cm.passive_ids)) {
1418                /* List is sorted by LRU, start from tail,
1419                 * stop when we see a recently used entry */
1420                p = list_entry(priv->cm.passive_ids.prev, typeof(*p), list);
1421                if (time_before_eq(jiffies, p->jiffies + IPOIB_CM_RX_TIMEOUT))
1422                        break;
1423                list_move(&p->list, &priv->cm.rx_error_list);
1424                p->state = IPOIB_CM_RX_ERROR;
1425                spin_unlock_irq(&priv->lock);
1426                ret = ib_modify_qp(p->qp, &ipoib_cm_err_attr, IB_QP_STATE);
1427                if (ret)
1428                        ipoib_warn(priv, "unable to move qp to error state: %d\n", ret);
1429                spin_lock_irq(&priv->lock);
1430        }
1431
1432        if (!list_empty(&priv->cm.passive_ids))
1433                queue_delayed_work(ipoib_workqueue,
1434                                   &priv->cm.stale_task, IPOIB_CM_RX_DELAY);
1435        spin_unlock_irq(&priv->lock);
1436}
1437
1438
1439static ssize_t show_mode(struct device *d, struct device_attribute *attr,
1440                         char *buf)
1441{
1442        struct ipoib_dev_priv *priv = netdev_priv(to_net_dev(d));
1443
1444        if (test_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags))
1445                return sprintf(buf, "connected\n");
1446        else
1447                return sprintf(buf, "datagram\n");
1448}
1449
1450static ssize_t set_mode(struct device *d, struct device_attribute *attr,
1451                        const char *buf, size_t count)
1452{
1453        struct net_device *dev = to_net_dev(d);
1454        struct ipoib_dev_priv *priv = netdev_priv(dev);
1455
1456        if (!rtnl_trylock())
1457                return restart_syscall();
1458
1459        /* flush paths if we switch modes so that connections are restarted */
1460        if (IPOIB_CM_SUPPORTED(dev->dev_addr) && !strcmp(buf, "connected\n")) {
1461                set_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
1462                ipoib_warn(priv, "enabling connected mode "
1463                           "will cause multicast packet drops\n");
1464
1465                dev->features &= ~(NETIF_F_IP_CSUM | NETIF_F_SG | NETIF_F_TSO);
1466                rtnl_unlock();
1467                priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
1468
1469                ipoib_flush_paths(dev);
1470                return count;
1471        }
1472
1473        if (!strcmp(buf, "datagram\n")) {
1474                clear_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
1475
1476                if (test_bit(IPOIB_FLAG_CSUM, &priv->flags)) {
1477                        dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
1478                        if (priv->hca_caps & IB_DEVICE_UD_TSO)
1479                                dev->features |= NETIF_F_TSO;
1480                }
1481                dev_set_mtu(dev, min(priv->mcast_mtu, dev->mtu));
1482                rtnl_unlock();
1483                ipoib_flush_paths(dev);
1484
1485                return count;
1486        }
1487        rtnl_unlock();
1488
1489        return -EINVAL;
1490}
1491
1492static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO, show_mode, set_mode);
1493
1494int ipoib_cm_add_mode_attr(struct net_device *dev)
1495{
1496        return device_create_file(&dev->dev, &dev_attr_mode);
1497}
1498
1499static void ipoib_cm_create_srq(struct net_device *dev, int max_sge)
1500{
1501        struct ipoib_dev_priv *priv = netdev_priv(dev);
1502        struct ib_srq_init_attr srq_init_attr = {
1503                .attr = {
1504                        .max_wr  = ipoib_recvq_size,
1505                        .max_sge = max_sge
1506                }
1507        };
1508
1509        priv->cm.srq = ib_create_srq(priv->pd, &srq_init_attr);
1510        if (IS_ERR(priv->cm.srq)) {
1511                if (PTR_ERR(priv->cm.srq) != -ENOSYS)
1512                        printk(KERN_WARNING "%s: failed to allocate SRQ, error %ld\n",
1513                               priv->ca->name, PTR_ERR(priv->cm.srq));
1514                priv->cm.srq = NULL;
1515                return;
1516        }
1517
1518        priv->cm.srq_ring = vmalloc(ipoib_recvq_size * sizeof *priv->cm.srq_ring);
1519        if (!priv->cm.srq_ring) {
1520                printk(KERN_WARNING "%s: failed to allocate CM SRQ ring (%d entries)\n",
1521                       priv->ca->name, ipoib_recvq_size);
1522                ib_destroy_srq(priv->cm.srq);
1523                priv->cm.srq = NULL;
1524                return;
1525        }
1526
1527        memset(priv->cm.srq_ring, 0, ipoib_recvq_size * sizeof *priv->cm.srq_ring);
1528}
1529
1530int ipoib_cm_dev_init(struct net_device *dev)
1531{
1532        struct ipoib_dev_priv *priv = netdev_priv(dev);
1533        int i, ret;
1534        struct ib_device_attr attr;
1535
1536        INIT_LIST_HEAD(&priv->cm.passive_ids);
1537        INIT_LIST_HEAD(&priv->cm.reap_list);
1538        INIT_LIST_HEAD(&priv->cm.start_list);
1539        INIT_LIST_HEAD(&priv->cm.rx_error_list);
1540        INIT_LIST_HEAD(&priv->cm.rx_flush_list);
1541        INIT_LIST_HEAD(&priv->cm.rx_drain_list);
1542        INIT_LIST_HEAD(&priv->cm.rx_reap_list);
1543        INIT_WORK(&priv->cm.start_task, ipoib_cm_tx_start);
1544        INIT_WORK(&priv->cm.reap_task, ipoib_cm_tx_reap);
1545        INIT_WORK(&priv->cm.skb_task, ipoib_cm_skb_reap);
1546        INIT_WORK(&priv->cm.rx_reap_task, ipoib_cm_rx_reap);
1547        INIT_DELAYED_WORK(&priv->cm.stale_task, ipoib_cm_stale_task);
1548
1549        skb_queue_head_init(&priv->cm.skb_queue);
1550
1551        ret = ib_query_device(priv->ca, &attr);
1552        if (ret) {
1553                printk(KERN_WARNING "ib_query_device() failed with %d\n", ret);
1554                return ret;
1555        }
1556
1557        ipoib_dbg(priv, "max_srq_sge=%d\n", attr.max_srq_sge);
1558
1559        attr.max_srq_sge = min_t(int, IPOIB_CM_RX_SG, attr.max_srq_sge);
1560        ipoib_cm_create_srq(dev, attr.max_srq_sge);
1561        if (ipoib_cm_has_srq(dev)) {
1562                priv->cm.max_cm_mtu = attr.max_srq_sge * PAGE_SIZE - 0x10;
1563                priv->cm.num_frags  = attr.max_srq_sge;
1564                ipoib_dbg(priv, "max_cm_mtu = 0x%x, num_frags=%d\n",
1565                          priv->cm.max_cm_mtu, priv->cm.num_frags);
1566        } else {
1567                priv->cm.max_cm_mtu = IPOIB_CM_MTU;
1568                priv->cm.num_frags  = IPOIB_CM_RX_SG;
1569        }
1570
1571        ipoib_cm_init_rx_wr(dev, &priv->cm.rx_wr, priv->cm.rx_sge);
1572
1573        if (ipoib_cm_has_srq(dev)) {
1574                for (i = 0; i < ipoib_recvq_size; ++i) {
1575                        if (!ipoib_cm_alloc_rx_skb(dev, priv->cm.srq_ring, i,
1576                                                   priv->cm.num_frags - 1,
1577                                                   priv->cm.srq_ring[i].mapping)) {
1578                                ipoib_warn(priv, "failed to allocate "
1579                                           "receive buffer %d\n", i);
1580                                ipoib_cm_dev_cleanup(dev);
1581                                return -ENOMEM;
1582                        }
1583
1584                        if (ipoib_cm_post_receive_srq(dev, i)) {
1585                                ipoib_warn(priv, "ipoib_cm_post_receive_srq "
1586                                           "failed for buf %d\n", i);
1587                                ipoib_cm_dev_cleanup(dev);
1588                                return -EIO;
1589                        }
1590                }
1591        }
1592
1593        priv->dev->dev_addr[0] = IPOIB_FLAGS_RC;
1594        return 0;
1595}
1596
1597void ipoib_cm_dev_cleanup(struct net_device *dev)
1598{
1599        struct ipoib_dev_priv *priv = netdev_priv(dev);
1600        int ret;
1601
1602        if (!priv->cm.srq)
1603                return;
1604
1605        ipoib_dbg(priv, "Cleanup ipoib connected mode.\n");
1606
1607        ret = ib_destroy_srq(priv->cm.srq);
1608        if (ret)
1609                ipoib_warn(priv, "ib_destroy_srq failed: %d\n", ret);
1610
1611        priv->cm.srq = NULL;
1612        if (!priv->cm.srq_ring)
1613                return;
1614
1615        ipoib_cm_free_rx_ring(dev, priv->cm.srq_ring);
1616        priv->cm.srq_ring = NULL;
1617}
1618