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