linux/net/rds/iw_cm.c
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   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 */
  44static 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 */
  52static 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 */
  69void 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
 106static 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
 141static 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
 146static 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 */
 172static 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 accomodate 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
 232out:
 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 */
 246static 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 == NULL) {
 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 == NULL) {
 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 == NULL) {
 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 == NULL) {
 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 == NULL) {
 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 == NULL) {
 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
 344out:
 345        return ret;
 346}
 347
 348static 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
 378int 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
 471out:
 472        rdma_reject(cm_id, NULL, 0);
 473        return destroy;
 474}
 475
 476
 477int 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
 502out:
 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
 515int 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);
 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
 566out:
 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 */
 575void 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
 692int 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 == NULL)
 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 */
 732void 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 */
 756void
 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}
 767