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