net/rds/ib_cm.c

   1 /*
   2  * Copyright (c) 2006 Oracle.  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 <linux/kernel.h>
  34 #include <linux/in.h>
  35 #include <linux/slab.h>
  36 #include <linux/vmalloc.h>
  37
  38 #include "rds.h"
  39 #include "ib.h"
  40
  41 /*
  42  * Set the selected protocol version
  43  */
  44 static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
  45 {
  46         conn->c_version = version;
  47 }
  48
  49 /*
  50  * Set up flow control
  51  */
  52 static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
  53 {
  54         struct rds_ib_connection *ic = conn->c_transport_data;
  55
  56         if (rds_ib_sysctl_flow_control && credits != 0) {
  57                 /* We're doing flow control */
  58                 ic->i_flowctl = 1;
  59                 rds_ib_send_add_credits(conn, credits);
  60         } else {
  61                 ic->i_flowctl = 0;
  62         }
  63 }
  64
  65 /*
  66  * Tune RNR behavior. Without flow control, we use a rather
  67  * low timeout, but not the absolute minimum - this should
  68  * be tunable.
  69  *
  70  * We already set the RNR retry count to 7 (which is the
  71  * smallest infinite number :-) above.
  72  * If flow control is off, we want to change this back to 0
  73  * so that we learn quickly when our credit accounting is
  74  * buggy.
  75  *
  76  * Caller passes in a qp_attr pointer - don't waste stack spacv
  77  * by allocation this twice.
  78  */
  79 static void
  80 rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
  81 {
  82         int ret;
  83
  84         attr->min_rnr_timer = IB_RNR_TIMER_000_32;
  85         ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
  86         if (ret)
  87                 printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
  88 }
  89
  90 /*
  91  * Connection established.
  92  * We get here for both outgoing and incoming connection.
  93  */
  94 void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
  95 {
  96         const struct rds_ib_connect_private *dp = NULL;
  97         struct rds_ib_connection *ic = conn->c_transport_data;
  98         struct rds_ib_device *rds_ibdev;
  99         struct ib_qp_attr qp_attr;
 100         int err;
 101
 102         if (event->param.conn.private_data_len >= sizeof(*dp)) {
 103                 dp = event->param.conn.private_data;
 104
 105                 /* make sure it isn't empty data */
 106                 if (dp->dp_protocol_major) {
 107                         rds_ib_set_protocol(conn,
 108                                 RDS_PROTOCOL(dp->dp_protocol_major,
 109                                 dp->dp_protocol_minor));
 110                         rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
 111                 }
 112         }
 113
 114         if (conn->c_version < RDS_PROTOCOL(3,1)) {
 115                 printk(KERN_NOTICE "RDS/IB: Connection to %pI4 version %u.%u failed,"
 116                        " no longer supported\n",
 117                        &conn->c_faddr,
 118                        RDS_PROTOCOL_MAJOR(conn->c_version),
 119                        RDS_PROTOCOL_MINOR(conn->c_version));
 120                 rds_conn_destroy(conn);
 121                 return;
 122         } else {
 123                 printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
 124                        &conn->c_faddr,
 125                        RDS_PROTOCOL_MAJOR(conn->c_version),
 126                        RDS_PROTOCOL_MINOR(conn->c_version),
 127                        ic->i_flowctl ? ", flow control" : "");
 128         }
 129
 130         /*
 131          * Init rings and fill recv. this needs to wait until protocol negotiation
 132          * is complete, since ring layout is different from 3.0 to 3.1.
 133          */
 134         rds_ib_send_init_ring(ic);
 135         rds_ib_recv_init_ring(ic);
 136         /* Post receive buffers - as a side effect, this will update
 137          * the posted credit count. */
 138         rds_ib_recv_refill(conn, 1);
 139
 140         /* Tune RNR behavior */
 141         rds_ib_tune_rnr(ic, &qp_attr);
 142
 143         qp_attr.qp_state = IB_QPS_RTS;
 144         err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
 145         if (err)
 146                 printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
 147
 148         /* update ib_device with this local ipaddr & conn */
 149         rds_ibdev = ib_get_client_data(ic->i_cm_id->device, &rds_ib_client);
 150         err = rds_ib_update_ipaddr(rds_ibdev, conn->c_laddr);
 151         if (err)
 152                 printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n", err);
 153         rds_ib_add_conn(rds_ibdev, conn);
 154
 155         /* If the peer gave us the last packet it saw, process this as if
 156          * we had received a regular ACK. */
 157         if (dp && dp->dp_ack_seq)
 158                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
 159
 160         rds_connect_complete(conn);
 161 }
 162
 163 static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
 164                         struct rdma_conn_param *conn_param,
 165                         struct rds_ib_connect_private *dp,
 166                         u32 protocol_version,
 167                         u32 max_responder_resources,
 168                         u32 max_initiator_depth)
 169 {
 170         struct rds_ib_connection *ic = conn->c_transport_data;
 171         struct rds_ib_device *rds_ibdev;
 172
 173         memset(conn_param, 0, sizeof(struct rdma_conn_param));
 174
 175         rds_ibdev = ib_get_client_data(ic->i_cm_id->device, &rds_ib_client);
 176
 177         conn_param->responder_resources =
 178                 min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
 179         conn_param->initiator_depth =
 180                 min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
 181         conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
 182         conn_param->rnr_retry_count = 7;
 183
 184         if (dp) {
 185                 memset(dp, 0, sizeof(*dp));
 186                 dp->dp_saddr = conn->c_laddr;
 187                 dp->dp_daddr = conn->c_faddr;
 188                 dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
 189                 dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
 190                 dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
 191                 dp->dp_ack_seq = rds_ib_piggyb_ack(ic);
 192
 193                 /* Advertise flow control */
 194                 if (ic->i_flowctl) {
 195                         unsigned int credits;
 196
 197                         credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
 198                         dp->dp_credit = cpu_to_be32(credits);
 199                         atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
 200                 }
 201
 202                 conn_param->private_data = dp;
 203                 conn_param->private_data_len = sizeof(*dp);
 204         }
 205 }
 206
 207 static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
 208 {
 209         rdsdebug("event %u data %p\n", event->event, data);
 210 }
 211
 212 static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
 213 {
 214         struct rds_connection *conn = data;
 215         struct rds_ib_connection *ic = conn->c_transport_data;
 216
 217         rdsdebug("conn %p ic %p event %u\n", conn, ic, event->event);
 218
 219         switch (event->event) {
 220         case IB_EVENT_COMM_EST:
 221                 rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
 222                 break;
 223         default:
 224                 rdsdebug("Fatal QP Event %u "
 225                         "- connection %pI4->%pI4, reconnecting\n",
 226                         event->event, &conn->c_laddr, &conn->c_faddr);
 227                 rds_conn_drop(conn);
 228                 break;
 229         }
 230 }
 231
 232 /*
 233  * This needs to be very careful to not leave IS_ERR pointers around for
 234  * cleanup to trip over.
 235  */
 236 static int rds_ib_setup_qp(struct rds_connection *conn)
 237 {
 238         struct rds_ib_connection *ic = conn->c_transport_data;
 239         struct ib_device *dev = ic->i_cm_id->device;
 240         struct ib_qp_init_attr attr;
 241         struct rds_ib_device *rds_ibdev;
 242         int ret;
 243
 244         /* rds_ib_add_one creates a rds_ib_device object per IB device,
 245          * and allocates a protection domain, memory range and FMR pool
 246          * for each.  If that fails for any reason, it will not register
 247          * the rds_ibdev at all.
 248          */
 249         rds_ibdev = ib_get_client_data(dev, &rds_ib_client);
 250         if (!rds_ibdev) {
 251                 if (printk_ratelimit())
 252                         printk(KERN_NOTICE "RDS/IB: No client_data for device %s\n",
 253                                         dev->name);
 254                 return -EOPNOTSUPP;
 255         }
 256
 257         if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
 258                 rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
 259         if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
 260                 rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
 261
 262         /* Protection domain and memory range */
 263         ic->i_pd = rds_ibdev->pd;
 264         ic->i_mr = rds_ibdev->mr;
 265
 266         ic->i_send_cq = ib_create_cq(dev, rds_ib_send_cq_comp_handler,
 267                                      rds_ib_cq_event_handler, conn,
 268                                      ic->i_send_ring.w_nr + 1, 0);
 269         if (IS_ERR(ic->i_send_cq)) {
 270                 ret = PTR_ERR(ic->i_send_cq);
 271                 ic->i_send_cq = NULL;
 272                 rdsdebug("ib_create_cq send failed: %d\n", ret);
 273                 goto out;
 274         }
 275
 276         ic->i_recv_cq = ib_create_cq(dev, rds_ib_recv_cq_comp_handler,
 277                                      rds_ib_cq_event_handler, conn,
 278                                      ic->i_recv_ring.w_nr, 0);
 279         if (IS_ERR(ic->i_recv_cq)) {
 280                 ret = PTR_ERR(ic->i_recv_cq);
 281                 ic->i_recv_cq = NULL;
 282                 rdsdebug("ib_create_cq recv failed: %d\n", ret);
 283                 goto out;
 284         }
 285
 286         ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
 287         if (ret) {
 288                 rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
 289                 goto out;
 290         }
 291
 292         ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
 293         if (ret) {
 294                 rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
 295                 goto out;
 296         }
 297
 298         /* XXX negotiate max send/recv with remote? */
 299         memset(&attr, 0, sizeof(attr));
 300         attr.event_handler = rds_ib_qp_event_handler;
 301         attr.qp_context = conn;
 302         /* + 1 to allow for the single ack message */
 303         attr.cap.max_send_wr = ic->i_send_ring.w_nr + 1;
 304         attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
 305         attr.cap.max_send_sge = rds_ibdev->max_sge;
 306         attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
 307         attr.sq_sig_type = IB_SIGNAL_REQ_WR;
 308         attr.qp_type = IB_QPT_RC;
 309         attr.send_cq = ic->i_send_cq;
 310         attr.recv_cq = ic->i_recv_cq;
 311
 312         /*
 313          * XXX this can fail if max_*_wr is too large?  Are we supposed
 314          * to back off until we get a value that the hardware can support?
 315          */
 316         ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
 317         if (ret) {
 318                 rdsdebug("rdma_create_qp failed: %d\n", ret);
 319                 goto out;
 320         }
 321
 322         ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
 323                                            ic->i_send_ring.w_nr *
 324                                                 sizeof(struct rds_header),
 325                                            &ic->i_send_hdrs_dma, GFP_KERNEL);
 326         if (!ic->i_send_hdrs) {
 327                 ret = -ENOMEM;
 328                 rdsdebug("ib_dma_alloc_coherent send failed\n");
 329                 goto out;
 330         }
 331
 332         ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
 333                                            ic->i_recv_ring.w_nr *
 334                                                 sizeof(struct rds_header),
 335                                            &ic->i_recv_hdrs_dma, GFP_KERNEL);
 336         if (!ic->i_recv_hdrs) {
 337                 ret = -ENOMEM;
 338                 rdsdebug("ib_dma_alloc_coherent recv failed\n");
 339                 goto out;
 340         }
 341
 342         ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
 343                                        &ic->i_ack_dma, GFP_KERNEL);
 344         if (!ic->i_ack) {
 345                 ret = -ENOMEM;
 346                 rdsdebug("ib_dma_alloc_coherent ack failed\n");
 347                 goto out;
 348         }
 349
 350         ic->i_sends = vmalloc(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work));
 351         if (!ic->i_sends) {
 352                 ret = -ENOMEM;
 353                 rdsdebug("send allocation failed\n");
 354                 goto out;
 355         }
 356         memset(ic->i_sends, 0, ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work));
 357
 358         ic->i_recvs = vmalloc(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work));
 359         if (!ic->i_recvs) {
 360                 ret = -ENOMEM;
 361                 rdsdebug("recv allocation failed\n");
 362                 goto out;
 363         }
 364         memset(ic->i_recvs, 0, ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work));
 365
 366         rds_ib_recv_init_ack(ic);
 367
 368         rdsdebug("conn %p pd %p mr %p cq %p %p\n", conn, ic->i_pd, ic->i_mr,
 369                  ic->i_send_cq, ic->i_recv_cq);
 370
 371 out:
 372         return ret;
 373 }
 374
 375 static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
 376 {
 377         const struct rds_ib_connect_private *dp = event->param.conn.private_data;
 378         u16 common;
 379         u32 version = 0;
 380
 381         /*
 382          * rdma_cm private data is odd - when there is any private data in the
 383          * request, we will be given a pretty large buffer without telling us the
 384          * original size. The only way to tell the difference is by looking at
 385          * the contents, which are initialized to zero.
 386          * If the protocol version fields aren't set, this is a connection attempt
 387          * from an older version. This could could be 3.0 or 2.0 - we can't tell.
 388          * We really should have changed this for OFED 1.3 :-(
 389          */
 390
 391         /* Be paranoid. RDS always has privdata */
 392         if (!event->param.conn.private_data_len) {
 393                 printk(KERN_NOTICE "RDS incoming connection has no private data, "
 394                         "rejecting\n");
 395                 return 0;
 396         }
 397
 398         /* Even if len is crap *now* I still want to check it. -ASG */
 399         if (event->param.conn.private_data_len < sizeof (*dp) ||
 400             dp->dp_protocol_major == 0)
 401                 return RDS_PROTOCOL_3_0;
 402
 403         common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
 404         if (dp->dp_protocol_major == 3 && common) {
 405                 version = RDS_PROTOCOL_3_0;
 406                 while ((common >>= 1) != 0)
 407                         version++;
 408         } else if (printk_ratelimit()) {
 409                 printk(KERN_NOTICE "RDS: Connection from %pI4 using "
 410                         "incompatible protocol version %u.%u\n",
 411                         &dp->dp_saddr,
 412                         dp->dp_protocol_major,
 413                         dp->dp_protocol_minor);
 414         }
 415         return version;
 416 }
 417
 418 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
 419                                     struct rdma_cm_event *event)
 420 {
 421         __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
 422         __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
 423         const struct rds_ib_connect_private *dp = event->param.conn.private_data;
 424         struct rds_ib_connect_private dp_rep;
 425         struct rds_connection *conn = NULL;
 426         struct rds_ib_connection *ic = NULL;
 427         struct rdma_conn_param conn_param;
 428         u32 version;
 429         int err, destroy = 1;
 430
 431         /* Check whether the remote protocol version matches ours. */
 432         version = rds_ib_protocol_compatible(event);
 433         if (!version)
 434                 goto out;
 435
 436         rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
 437                  "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
 438                  RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
 439                  (unsigned long long)be64_to_cpu(lguid),
 440                  (unsigned long long)be64_to_cpu(fguid));
 441
 442         conn = rds_conn_create(dp->dp_daddr, dp->dp_saddr, &rds_ib_transport,
 443                                GFP_KERNEL);
 444         if (IS_ERR(conn)) {
 445                 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
 446                 conn = NULL;
 447                 goto out;
 448         }
 449
 450         /*
 451          * The connection request may occur while the
 452          * previous connection exist, e.g. in case of failover.
 453          * But as connections may be initiated simultaneously
 454          * by both hosts, we have a random backoff mechanism -
 455          * see the comment above rds_queue_reconnect()
 456          */
 457         mutex_lock(&conn->c_cm_lock);
 458         if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
 459                 if (rds_conn_state(conn) == RDS_CONN_UP) {
 460                         rdsdebug("incoming connect while connecting\n");
 461                         rds_conn_drop(conn);
 462                         rds_ib_stats_inc(s_ib_listen_closed_stale);
 463                 } else
 464                 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
 465                         /* Wait and see - our connect may still be succeeding */
 466                         rds_ib_stats_inc(s_ib_connect_raced);
 467                 }
 468                 mutex_unlock(&conn->c_cm_lock);
 469                 goto out;
 470         }
 471
 472         ic = conn->c_transport_data;
 473
 474         rds_ib_set_protocol(conn, version);
 475         rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
 476
 477         /* If the peer gave us the last packet it saw, process this as if
 478          * we had received a regular ACK. */
 479         if (dp->dp_ack_seq)
 480                 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
 481
 482         BUG_ON(cm_id->context);
 483         BUG_ON(ic->i_cm_id);
 484
 485         ic->i_cm_id = cm_id;
 486         cm_id->context = conn;
 487
 488         /* We got halfway through setting up the ib_connection, if we
 489          * fail now, we have to take the long route out of this mess. */
 490         destroy = 0;
 491
 492         err = rds_ib_setup_qp(conn);
 493         if (err) {
 494                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
 495                 mutex_unlock(&conn->c_cm_lock);
 496                 goto out;
 497         }
 498
 499         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
 500                 event->param.conn.responder_resources,
 501                 event->param.conn.initiator_depth);
 502
 503         /* rdma_accept() calls rdma_reject() internally if it fails */
 504         err = rdma_accept(cm_id, &conn_param);
 505         mutex_unlock(&conn->c_cm_lock);
 506         if (err) {
 507                 rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
 508                 goto out;
 509         }
 510
 511         return 0;
 512
 513 out:
 514         rdma_reject(cm_id, NULL, 0);
 515         return destroy;
 516 }
 517
 518
 519 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
 520 {
 521         struct rds_connection *conn = cm_id->context;
 522         struct rds_ib_connection *ic = conn->c_transport_data;
 523         struct rdma_conn_param conn_param;
 524         struct rds_ib_connect_private dp;
 525         int ret;
 526
 527         /* If the peer doesn't do protocol negotiation, we must
 528          * default to RDSv3.0 */
 529         rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
 530         ic->i_flowctl = rds_ib_sysctl_flow_control;     /* advertise flow control */
 531
 532         ret = rds_ib_setup_qp(conn);
 533         if (ret) {
 534                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
 535                 goto out;
 536         }
 537
 538         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
 539                 UINT_MAX, UINT_MAX);
 540         ret = rdma_connect(cm_id, &conn_param);
 541         if (ret)
 542                 rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
 543
 544 out:
 545         /* Beware - returning non-zero tells the rdma_cm to destroy
 546          * the cm_id. We should certainly not do it as long as we still
 547          * "own" the cm_id. */
 548         if (ret) {
 549                 if (ic->i_cm_id == cm_id)
 550                         ret = 0;
 551         }
 552         return ret;
 553 }
 554
 555 int rds_ib_conn_connect(struct rds_connection *conn)
 556 {
 557         struct rds_ib_connection *ic = conn->c_transport_data;
 558         struct sockaddr_in src, dest;
 559         int ret;
 560
 561         /* XXX I wonder what affect the port space has */
 562         /* delegate cm event handler to rdma_transport */
 563         ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
 564                                      RDMA_PS_TCP);
 565         if (IS_ERR(ic->i_cm_id)) {
 566                 ret = PTR_ERR(ic->i_cm_id);
 567                 ic->i_cm_id = NULL;
 568                 rdsdebug("rdma_create_id() failed: %d\n", ret);
 569                 goto out;
 570         }
 571
 572         rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
 573
 574         src.sin_family = AF_INET;
 575         src.sin_addr.s_addr = (__force u32)conn->c_laddr;
 576         src.sin_port = (__force u16)htons(0);
 577
 578         dest.sin_family = AF_INET;
 579         dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
 580         dest.sin_port = (__force u16)htons(RDS_PORT);
 581
 582         ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
 583                                 (struct sockaddr *)&dest,
 584                                 RDS_RDMA_RESOLVE_TIMEOUT_MS);
 585         if (ret) {
 586                 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
 587                          ret);
 588                 rdma_destroy_id(ic->i_cm_id);
 589                 ic->i_cm_id = NULL;
 590         }
 591
 592 out:
 593         return ret;
 594 }
 595
 596 /*
 597  * This is so careful about only cleaning up resources that were built up
 598  * so that it can be called at any point during startup.  In fact it
 599  * can be called multiple times for a given connection.
 600  */
 601 void rds_ib_conn_shutdown(struct rds_connection *conn)
 602 {
 603         struct rds_ib_connection *ic = conn->c_transport_data;
 604         int err = 0;
 605
 606         rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
 607                  ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
 608                  ic->i_cm_id ? ic->i_cm_id->qp : NULL);
 609
 610         if (ic->i_cm_id) {
 611                 struct ib_device *dev = ic->i_cm_id->device;
 612
 613                 rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
 614                 err = rdma_disconnect(ic->i_cm_id);
 615                 if (err) {
 616                         /* Actually this may happen quite frequently, when
 617                          * an outgoing connect raced with an incoming connect.
 618                          */
 619                         rdsdebug("failed to disconnect, cm: %p err %d\n",
 620                                 ic->i_cm_id, err);
 621                 }
 622
 623                 /*
 624                  * Don't wait for the send ring to be empty -- there may be completed
 625                  * non-signaled entries sitting on there. We unmap these below.
 626                  */
 627                 wait_event(rds_ib_ring_empty_wait,
 628                         rds_ib_ring_empty(&ic->i_recv_ring));
 629
 630                 if (ic->i_send_hdrs)
 631                         ib_dma_free_coherent(dev,
 632                                            ic->i_send_ring.w_nr *
 633                                                 sizeof(struct rds_header),
 634                                            ic->i_send_hdrs,
 635                                            ic->i_send_hdrs_dma);
 636
 637                 if (ic->i_recv_hdrs)
 638                         ib_dma_free_coherent(dev,
 639                                            ic->i_recv_ring.w_nr *
 640                                                 sizeof(struct rds_header),
 641                                            ic->i_recv_hdrs,
 642                                            ic->i_recv_hdrs_dma);
 643
 644                 if (ic->i_ack)
 645                         ib_dma_free_coherent(dev, sizeof(struct rds_header),
 646                                              ic->i_ack, ic->i_ack_dma);
 647
 648                 if (ic->i_sends)
 649                         rds_ib_send_clear_ring(ic);
 650                 if (ic->i_recvs)
 651                         rds_ib_recv_clear_ring(ic);
 652
 653                 if (ic->i_cm_id->qp)
 654                         rdma_destroy_qp(ic->i_cm_id);
 655                 if (ic->i_send_cq)
 656                         ib_destroy_cq(ic->i_send_cq);
 657                 if (ic->i_recv_cq)
 658                         ib_destroy_cq(ic->i_recv_cq);
 659                 rdma_destroy_id(ic->i_cm_id);
 660
 661                 /*
 662                  * Move connection back to the nodev list.
 663                  */
 664                 if (ic->rds_ibdev)
 665                         rds_ib_remove_conn(ic->rds_ibdev, conn);
 666
 667                 ic->i_cm_id = NULL;
 668                 ic->i_pd = NULL;
 669                 ic->i_mr = NULL;
 670                 ic->i_send_cq = NULL;
 671                 ic->i_recv_cq = NULL;
 672                 ic->i_send_hdrs = NULL;
 673                 ic->i_recv_hdrs = NULL;
 674                 ic->i_ack = NULL;
 675         }
 676         BUG_ON(ic->rds_ibdev);
 677
 678         /* Clear pending transmit */
 679         if (ic->i_data_op) {
 680                 struct rds_message *rm;
 681
 682                 rm = container_of(ic->i_data_op, struct rds_message, data);
 683                 rds_message_put(rm);
 684                 ic->i_data_op = NULL;
 685         }
 686
 687         /* Clear the ACK state */
 688         clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
 689 #ifdef KERNEL_HAS_ATOMIC64
 690         atomic64_set(&ic->i_ack_next, 0);
 691 #else
 692         ic->i_ack_next = 0;
 693 #endif
 694         ic->i_ack_recv = 0;
 695
 696         /* Clear flow control state */
 697         ic->i_flowctl = 0;
 698         atomic_set(&ic->i_credits, 0);
 699
 700         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
 701         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
 702
 703         if (ic->i_ibinc) {
 704                 rds_inc_put(&ic->i_ibinc->ii_inc);
 705                 ic->i_ibinc = NULL;
 706         }
 707
 708         vfree(ic->i_sends);
 709         ic->i_sends = NULL;
 710         vfree(ic->i_recvs);
 711         ic->i_recvs = NULL;
 712 }
 713
 714 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
 715 {
 716         struct rds_ib_connection *ic;
 717         unsigned long flags;
 718
 719         /* XXX too lazy? */
 720         ic = kzalloc(sizeof(struct rds_ib_connection), GFP_KERNEL);
 721         if (!ic)
 722                 return -ENOMEM;
 723
 724         INIT_LIST_HEAD(&ic->ib_node);
 725         tasklet_init(&ic->i_recv_tasklet, rds_ib_recv_tasklet_fn,
 726                      (unsigned long) ic);
 727         mutex_init(&ic->i_recv_mutex);
 728 #ifndef KERNEL_HAS_ATOMIC64
 729         spin_lock_init(&ic->i_ack_lock);
 730 #endif
 731
 732         /*
 733          * rds_ib_conn_shutdown() waits for these to be emptied so they
 734          * must be initialized before it can be called.
 735          */
 736         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
 737         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
 738
 739         ic->conn = conn;
 740         conn->c_transport_data = ic;
 741
 742         spin_lock_irqsave(&ib_nodev_conns_lock, flags);
 743         list_add_tail(&ic->ib_node, &ib_nodev_conns);
 744         spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
 745
 746
 747         rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
 748         return 0;
 749 }
 750
 751 /*
 752  * Free a connection. Connection must be shut down and not set for reconnect.
 753  */
 754 void rds_ib_conn_free(void *arg)
 755 {
 756         struct rds_ib_connection *ic = arg;
 757         spinlock_t      *lock_ptr;
 758
 759         rdsdebug("ic %p\n", ic);
 760
 761         /*
 762          * Conn is either on a dev's list or on the nodev list.
 763          * A race with shutdown() or connect() would cause problems
 764          * (since rds_ibdev would change) but that should never happen.
 765          */
 766         lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
 767
 768         spin_lock_irq(lock_ptr);
 769         list_del(&ic->ib_node);
 770         spin_unlock_irq(lock_ptr);
 771
 772         kfree(ic);
 773 }
 774
 775
 776 /*
 777  * An error occurred on the connection
 778  */
 779 void
 780 __rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
 781 {
 782         va_list ap;
 783
 784         rds_conn_drop(conn);
 785
 786         va_start(ap, fmt);
 787         vprintk(fmt, ap);
 788         va_end(ap);
 789 }