net/rds/ib_cm.c

   1 /*
   2  * Copyright (c) 2006, 2018 Oracle and/or its affiliates. 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 #include <linux/ratelimit.h>
  38 #include <net/addrconf.h>
  39
  40 #include "rds_single_path.h"
  41 #include "rds.h"
  42 #include "ib.h"
  43 #include "ib_mr.h"
  44
  45 /*
  46  * Set the selected protocol version
  47  */
  48 static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
  49 {
  50         conn->c_version = version;
  51 }
  52
  53 /*
  54  * Set up flow control
  55  */
  56 static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
  57 {
  58         struct rds_ib_connection *ic = conn->c_transport_data;
  59
  60         if (rds_ib_sysctl_flow_control && credits != 0) {
  61                 /* We're doing flow control */
  62                 ic->i_flowctl = 1;
  63                 rds_ib_send_add_credits(conn, credits);
  64         } else {
  65                 ic->i_flowctl = 0;
  66         }
  67 }
  68
  69 /*
  70  * Tune RNR behavior. Without flow control, we use a rather
  71  * low timeout, but not the absolute minimum - this should
  72  * be tunable.
  73  *
  74  * We already set the RNR retry count to 7 (which is the
  75  * smallest infinite number :-) above.
  76  * If flow control is off, we want to change this back to 0
  77  * so that we learn quickly when our credit accounting is
  78  * buggy.
  79  *
  80  * Caller passes in a qp_attr pointer - don't waste stack spacv
  81  * by allocation this twice.
  82  */
  83 static void
  84 rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
  85 {
  86         int ret;
  87
  88         attr->min_rnr_timer = IB_RNR_TIMER_000_32;
  89         ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
  90         if (ret)
  91                 printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
  92 }
  93
  94 /*
  95  * Connection established.
  96  * We get here for both outgoing and incoming connection.
  97  */
  98 void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
  99 {
 100         struct rds_ib_connection *ic = conn->c_transport_data;
 101         const union rds_ib_conn_priv *dp = NULL;
 102         struct ib_qp_attr qp_attr;
 103         __be64 ack_seq = 0;
 104         __be32 credit = 0;
 105         u8 major = 0;
 106         u8 minor = 0;
 107         int err;
 108
 109         dp = event->param.conn.private_data;
 110         if (conn->c_isv6) {
 111                 if (event->param.conn.private_data_len >=
 112                     sizeof(struct rds6_ib_connect_private)) {
 113                         major = dp->ricp_v6.dp_protocol_major;
 114                         minor = dp->ricp_v6.dp_protocol_minor;
 115                         credit = dp->ricp_v6.dp_credit;
 116                         /* dp structure start is not guaranteed to be 8 bytes
 117                          * aligned.  Since dp_ack_seq is 64-bit extended load
 118                          * operations can be used so go through get_unaligned
 119                          * to avoid unaligned errors.
 120                          */
 121                         ack_seq = get_unaligned(&dp->ricp_v6.dp_ack_seq);
 122                 }
 123         } else if (event->param.conn.private_data_len >=
 124                    sizeof(struct rds_ib_connect_private)) {
 125                 major = dp->ricp_v4.dp_protocol_major;
 126                 minor = dp->ricp_v4.dp_protocol_minor;
 127                 credit = dp->ricp_v4.dp_credit;
 128                 ack_seq = get_unaligned(&dp->ricp_v4.dp_ack_seq);
 129         }
 130
 131         /* make sure it isn't empty data */
 132         if (major) {
 133                 rds_ib_set_protocol(conn, RDS_PROTOCOL(major, minor));
 134                 rds_ib_set_flow_control(conn, be32_to_cpu(credit));
 135         }
 136
 137         if (conn->c_version < RDS_PROTOCOL_VERSION) {
 138                 if (conn->c_version != RDS_PROTOCOL_COMPAT_VERSION) {
 139                         pr_notice("RDS/IB: Connection <%pI6c,%pI6c> version %u.%u no longer supported\n",
 140                                   &conn->c_laddr, &conn->c_faddr,
 141                                   RDS_PROTOCOL_MAJOR(conn->c_version),
 142                                   RDS_PROTOCOL_MINOR(conn->c_version));
 143                         rds_conn_destroy(conn);
 144                         return;
 145                 }
 146         }
 147
 148         pr_notice("RDS/IB: %s conn connected <%pI6c,%pI6c,%d> version %u.%u%s\n",
 149                   ic->i_active_side ? "Active" : "Passive",
 150                   &conn->c_laddr, &conn->c_faddr, conn->c_tos,
 151                   RDS_PROTOCOL_MAJOR(conn->c_version),
 152                   RDS_PROTOCOL_MINOR(conn->c_version),
 153                   ic->i_flowctl ? ", flow control" : "");
 154
 155         atomic_set(&ic->i_cq_quiesce, 0);
 156
 157         /* Init rings and fill recv. this needs to wait until protocol
 158          * negotiation is complete, since ring layout is different
 159          * from 3.1 to 4.1.
 160          */
 161         rds_ib_send_init_ring(ic);
 162         rds_ib_recv_init_ring(ic);
 163         /* Post receive buffers - as a side effect, this will update
 164          * the posted credit count. */
 165         rds_ib_recv_refill(conn, 1, GFP_KERNEL);
 166
 167         /* Tune RNR behavior */
 168         rds_ib_tune_rnr(ic, &qp_attr);
 169
 170         qp_attr.qp_state = IB_QPS_RTS;
 171         err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
 172         if (err)
 173                 printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
 174
 175         /* update ib_device with this local ipaddr */
 176         err = rds_ib_update_ipaddr(ic->rds_ibdev, &conn->c_laddr);
 177         if (err)
 178                 printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
 179                         err);
 180
 181         /* If the peer gave us the last packet it saw, process this as if
 182          * we had received a regular ACK. */
 183         if (dp) {
 184                 if (ack_seq)
 185                         rds_send_drop_acked(conn, be64_to_cpu(ack_seq),
 186                                             NULL);
 187         }
 188
 189         conn->c_proposed_version = conn->c_version;
 190         rds_connect_complete(conn);
 191 }
 192
 193 static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
 194                                       struct rdma_conn_param *conn_param,
 195                                       union rds_ib_conn_priv *dp,
 196                                       u32 protocol_version,
 197                                       u32 max_responder_resources,
 198                                       u32 max_initiator_depth,
 199                                       bool isv6)
 200 {
 201         struct rds_ib_connection *ic = conn->c_transport_data;
 202         struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
 203
 204         memset(conn_param, 0, sizeof(struct rdma_conn_param));
 205
 206         conn_param->responder_resources =
 207                 min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
 208         conn_param->initiator_depth =
 209                 min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
 210         conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
 211         conn_param->rnr_retry_count = 7;
 212
 213         if (dp) {
 214                 memset(dp, 0, sizeof(*dp));
 215                 if (isv6) {
 216                         dp->ricp_v6.dp_saddr = conn->c_laddr;
 217                         dp->ricp_v6.dp_daddr = conn->c_faddr;
 218                         dp->ricp_v6.dp_protocol_major =
 219                             RDS_PROTOCOL_MAJOR(protocol_version);
 220                         dp->ricp_v6.dp_protocol_minor =
 221                             RDS_PROTOCOL_MINOR(protocol_version);
 222                         dp->ricp_v6.dp_protocol_minor_mask =
 223                             cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
 224                         dp->ricp_v6.dp_ack_seq =
 225                             cpu_to_be64(rds_ib_piggyb_ack(ic));
 226                         dp->ricp_v6.dp_cmn.ricpc_dp_toss = conn->c_tos;
 227
 228                         conn_param->private_data = &dp->ricp_v6;
 229                         conn_param->private_data_len = sizeof(dp->ricp_v6);
 230                 } else {
 231                         dp->ricp_v4.dp_saddr = conn->c_laddr.s6_addr32[3];
 232                         dp->ricp_v4.dp_daddr = conn->c_faddr.s6_addr32[3];
 233                         dp->ricp_v4.dp_protocol_major =
 234                             RDS_PROTOCOL_MAJOR(protocol_version);
 235                         dp->ricp_v4.dp_protocol_minor =
 236                             RDS_PROTOCOL_MINOR(protocol_version);
 237                         dp->ricp_v4.dp_protocol_minor_mask =
 238                             cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
 239                         dp->ricp_v4.dp_ack_seq =
 240                             cpu_to_be64(rds_ib_piggyb_ack(ic));
 241                         dp->ricp_v4.dp_cmn.ricpc_dp_toss = conn->c_tos;
 242
 243                         conn_param->private_data = &dp->ricp_v4;
 244                         conn_param->private_data_len = sizeof(dp->ricp_v4);
 245                 }
 246
 247                 /* Advertise flow control */
 248                 if (ic->i_flowctl) {
 249                         unsigned int credits;
 250
 251                         credits = IB_GET_POST_CREDITS
 252                                 (atomic_read(&ic->i_credits));
 253                         if (isv6)
 254                                 dp->ricp_v6.dp_credit = cpu_to_be32(credits);
 255                         else
 256                                 dp->ricp_v4.dp_credit = cpu_to_be32(credits);
 257                         atomic_sub(IB_SET_POST_CREDITS(credits),
 258                                    &ic->i_credits);
 259                 }
 260         }
 261 }
 262
 263 static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
 264 {
 265         rdsdebug("event %u (%s) data %p\n",
 266                  event->event, ib_event_msg(event->event), data);
 267 }
 268
 269 /* Plucking the oldest entry from the ring can be done concurrently with
 270  * the thread refilling the ring.  Each ring operation is protected by
 271  * spinlocks and the transient state of refilling doesn't change the
 272  * recording of which entry is oldest.
 273  *
 274  * This relies on IB only calling one cq comp_handler for each cq so that
 275  * there will only be one caller of rds_recv_incoming() per RDS connection.
 276  */
 277 static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context)
 278 {
 279         struct rds_connection *conn = context;
 280         struct rds_ib_connection *ic = conn->c_transport_data;
 281
 282         rdsdebug("conn %p cq %p\n", conn, cq);
 283
 284         rds_ib_stats_inc(s_ib_evt_handler_call);
 285
 286         tasklet_schedule(&ic->i_recv_tasklet);
 287 }
 288
 289 static void poll_scq(struct rds_ib_connection *ic, struct ib_cq *cq,
 290                      struct ib_wc *wcs)
 291 {
 292         int nr, i;
 293         struct ib_wc *wc;
 294
 295         while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
 296                 for (i = 0; i < nr; i++) {
 297                         wc = wcs + i;
 298                         rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
 299                                  (unsigned long long)wc->wr_id, wc->status,
 300                                  wc->byte_len, be32_to_cpu(wc->ex.imm_data));
 301
 302                         if (wc->wr_id <= ic->i_send_ring.w_nr ||
 303                             wc->wr_id == RDS_IB_ACK_WR_ID)
 304                                 rds_ib_send_cqe_handler(ic, wc);
 305                         else
 306                                 rds_ib_mr_cqe_handler(ic, wc);
 307
 308                 }
 309         }
 310 }
 311
 312 static void rds_ib_tasklet_fn_send(unsigned long data)
 313 {
 314         struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
 315         struct rds_connection *conn = ic->conn;
 316
 317         rds_ib_stats_inc(s_ib_tasklet_call);
 318
 319         /* if cq has been already reaped, ignore incoming cq event */
 320         if (atomic_read(&ic->i_cq_quiesce))
 321                 return;
 322
 323         poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
 324         ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
 325         poll_scq(ic, ic->i_send_cq, ic->i_send_wc);
 326
 327         if (rds_conn_up(conn) &&
 328             (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags) ||
 329             test_bit(0, &conn->c_map_queued)))
 330                 rds_send_xmit(&ic->conn->c_path[0]);
 331 }
 332
 333 static void poll_rcq(struct rds_ib_connection *ic, struct ib_cq *cq,
 334                      struct ib_wc *wcs,
 335                      struct rds_ib_ack_state *ack_state)
 336 {
 337         int nr, i;
 338         struct ib_wc *wc;
 339
 340         while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
 341                 for (i = 0; i < nr; i++) {
 342                         wc = wcs + i;
 343                         rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
 344                                  (unsigned long long)wc->wr_id, wc->status,
 345                                  wc->byte_len, be32_to_cpu(wc->ex.imm_data));
 346
 347                         rds_ib_recv_cqe_handler(ic, wc, ack_state);
 348                 }
 349         }
 350 }
 351
 352 static void rds_ib_tasklet_fn_recv(unsigned long data)
 353 {
 354         struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
 355         struct rds_connection *conn = ic->conn;
 356         struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
 357         struct rds_ib_ack_state state;
 358
 359         if (!rds_ibdev)
 360                 rds_conn_drop(conn);
 361
 362         rds_ib_stats_inc(s_ib_tasklet_call);
 363
 364         /* if cq has been already reaped, ignore incoming cq event */
 365         if (atomic_read(&ic->i_cq_quiesce))
 366                 return;
 367
 368         memset(&state, 0, sizeof(state));
 369         poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
 370         ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
 371         poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
 372
 373         if (state.ack_next_valid)
 374                 rds_ib_set_ack(ic, state.ack_next, state.ack_required);
 375         if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) {
 376                 rds_send_drop_acked(conn, state.ack_recv, NULL);
 377                 ic->i_ack_recv = state.ack_recv;
 378         }
 379
 380         if (rds_conn_up(conn))
 381                 rds_ib_attempt_ack(ic);
 382 }
 383
 384 static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
 385 {
 386         struct rds_connection *conn = data;
 387         struct rds_ib_connection *ic = conn->c_transport_data;
 388
 389         rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
 390                  ib_event_msg(event->event));
 391
 392         switch (event->event) {
 393         case IB_EVENT_COMM_EST:
 394                 rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
 395                 break;
 396         default:
 397                 rdsdebug("Fatal QP Event %u (%s) - connection %pI6c->%pI6c, reconnecting\n",
 398                          event->event, ib_event_msg(event->event),
 399                          &conn->c_laddr, &conn->c_faddr);
 400                 rds_conn_drop(conn);
 401                 break;
 402         }
 403 }
 404
 405 static void rds_ib_cq_comp_handler_send(struct ib_cq *cq, void *context)
 406 {
 407         struct rds_connection *conn = context;
 408         struct rds_ib_connection *ic = conn->c_transport_data;
 409
 410         rdsdebug("conn %p cq %p\n", conn, cq);
 411
 412         rds_ib_stats_inc(s_ib_evt_handler_call);
 413
 414         tasklet_schedule(&ic->i_send_tasklet);
 415 }
 416
 417 static inline int ibdev_get_unused_vector(struct rds_ib_device *rds_ibdev)
 418 {
 419         int min = rds_ibdev->vector_load[rds_ibdev->dev->num_comp_vectors - 1];
 420         int index = rds_ibdev->dev->num_comp_vectors - 1;
 421         int i;
 422
 423         for (i = rds_ibdev->dev->num_comp_vectors - 1; i >= 0; i--) {
 424                 if (rds_ibdev->vector_load[i] < min) {
 425                         index = i;
 426                         min = rds_ibdev->vector_load[i];
 427                 }
 428         }
 429
 430         rds_ibdev->vector_load[index]++;
 431         return index;
 432 }
 433
 434 static inline void ibdev_put_vector(struct rds_ib_device *rds_ibdev, int index)
 435 {
 436         rds_ibdev->vector_load[index]--;
 437 }
 438
 439 /*
 440  * This needs to be very careful to not leave IS_ERR pointers around for
 441  * cleanup to trip over.
 442  */
 443 static int rds_ib_setup_qp(struct rds_connection *conn)
 444 {
 445         struct rds_ib_connection *ic = conn->c_transport_data;
 446         struct ib_device *dev = ic->i_cm_id->device;
 447         struct ib_qp_init_attr attr;
 448         struct ib_cq_init_attr cq_attr = {};
 449         struct rds_ib_device *rds_ibdev;
 450         int ret, fr_queue_space;
 451
 452         /*
 453          * It's normal to see a null device if an incoming connection races
 454          * with device removal, so we don't print a warning.
 455          */
 456         rds_ibdev = rds_ib_get_client_data(dev);
 457         if (!rds_ibdev)
 458                 return -EOPNOTSUPP;
 459
 460         /* The fr_queue_space is currently set to 512, to add extra space on
 461          * completion queue and send queue. This extra space is used for FRMR
 462          * registration and invalidation work requests
 463          */
 464         fr_queue_space = (rds_ibdev->use_fastreg ? RDS_IB_DEFAULT_FR_WR : 0);
 465
 466         /* add the conn now so that connection establishment has the dev */
 467         rds_ib_add_conn(rds_ibdev, conn);
 468
 469         if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
 470                 rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
 471         if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
 472                 rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
 473
 474         /* Protection domain and memory range */
 475         ic->i_pd = rds_ibdev->pd;
 476
 477         ic->i_scq_vector = ibdev_get_unused_vector(rds_ibdev);
 478         cq_attr.cqe = ic->i_send_ring.w_nr + fr_queue_space + 1;
 479         cq_attr.comp_vector = ic->i_scq_vector;
 480         ic->i_send_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_send,
 481                                      rds_ib_cq_event_handler, conn,
 482                                      &cq_attr);
 483         if (IS_ERR(ic->i_send_cq)) {
 484                 ret = PTR_ERR(ic->i_send_cq);
 485                 ic->i_send_cq = NULL;
 486                 ibdev_put_vector(rds_ibdev, ic->i_scq_vector);
 487                 rdsdebug("ib_create_cq send failed: %d\n", ret);
 488                 goto rds_ibdev_out;
 489         }
 490
 491         ic->i_rcq_vector = ibdev_get_unused_vector(rds_ibdev);
 492         cq_attr.cqe = ic->i_recv_ring.w_nr;
 493         cq_attr.comp_vector = ic->i_rcq_vector;
 494         ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv,
 495                                      rds_ib_cq_event_handler, conn,
 496                                      &cq_attr);
 497         if (IS_ERR(ic->i_recv_cq)) {
 498                 ret = PTR_ERR(ic->i_recv_cq);
 499                 ic->i_recv_cq = NULL;
 500                 ibdev_put_vector(rds_ibdev, ic->i_rcq_vector);
 501                 rdsdebug("ib_create_cq recv failed: %d\n", ret);
 502                 goto send_cq_out;
 503         }
 504
 505         ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
 506         if (ret) {
 507                 rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
 508                 goto recv_cq_out;
 509         }
 510
 511         ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
 512         if (ret) {
 513                 rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
 514                 goto recv_cq_out;
 515         }
 516
 517         /* XXX negotiate max send/recv with remote? */
 518         memset(&attr, 0, sizeof(attr));
 519         attr.event_handler = rds_ib_qp_event_handler;
 520         attr.qp_context = conn;
 521         /* + 1 to allow for the single ack message */
 522         attr.cap.max_send_wr = ic->i_send_ring.w_nr + fr_queue_space + 1;
 523         attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
 524         attr.cap.max_send_sge = rds_ibdev->max_sge;
 525         attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
 526         attr.sq_sig_type = IB_SIGNAL_REQ_WR;
 527         attr.qp_type = IB_QPT_RC;
 528         attr.send_cq = ic->i_send_cq;
 529         attr.recv_cq = ic->i_recv_cq;
 530         atomic_set(&ic->i_fastreg_wrs, RDS_IB_DEFAULT_FR_WR);
 531
 532         /*
 533          * XXX this can fail if max_*_wr is too large?  Are we supposed
 534          * to back off until we get a value that the hardware can support?
 535          */
 536         ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
 537         if (ret) {
 538                 rdsdebug("rdma_create_qp failed: %d\n", ret);
 539                 goto recv_cq_out;
 540         }
 541
 542         ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
 543                                            ic->i_send_ring.w_nr *
 544                                                 sizeof(struct rds_header),
 545                                            &ic->i_send_hdrs_dma, GFP_KERNEL);
 546         if (!ic->i_send_hdrs) {
 547                 ret = -ENOMEM;
 548                 rdsdebug("ib_dma_alloc_coherent send failed\n");
 549                 goto qp_out;
 550         }
 551
 552         ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
 553                                            ic->i_recv_ring.w_nr *
 554                                                 sizeof(struct rds_header),
 555                                            &ic->i_recv_hdrs_dma, GFP_KERNEL);
 556         if (!ic->i_recv_hdrs) {
 557                 ret = -ENOMEM;
 558                 rdsdebug("ib_dma_alloc_coherent recv failed\n");
 559                 goto send_hdrs_dma_out;
 560         }
 561
 562         ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
 563                                        &ic->i_ack_dma, GFP_KERNEL);
 564         if (!ic->i_ack) {
 565                 ret = -ENOMEM;
 566                 rdsdebug("ib_dma_alloc_coherent ack failed\n");
 567                 goto recv_hdrs_dma_out;
 568         }
 569
 570         ic->i_sends = vzalloc_node(array_size(sizeof(struct rds_ib_send_work),
 571                                               ic->i_send_ring.w_nr),
 572                                    ibdev_to_node(dev));
 573         if (!ic->i_sends) {
 574                 ret = -ENOMEM;
 575                 rdsdebug("send allocation failed\n");
 576                 goto ack_dma_out;
 577         }
 578
 579         ic->i_recvs = vzalloc_node(array_size(sizeof(struct rds_ib_recv_work),
 580                                               ic->i_recv_ring.w_nr),
 581                                    ibdev_to_node(dev));
 582         if (!ic->i_recvs) {
 583                 ret = -ENOMEM;
 584                 rdsdebug("recv allocation failed\n");
 585                 goto sends_out;
 586         }
 587
 588         rds_ib_recv_init_ack(ic);
 589
 590         rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd,
 591                  ic->i_send_cq, ic->i_recv_cq);
 592
 593         goto out;
 594
 595 sends_out:
 596         vfree(ic->i_sends);
 597 ack_dma_out:
 598         ib_dma_free_coherent(dev, sizeof(struct rds_header),
 599                              ic->i_ack, ic->i_ack_dma);
 600 recv_hdrs_dma_out:
 601         ib_dma_free_coherent(dev, ic->i_recv_ring.w_nr *
 602                                         sizeof(struct rds_header),
 603                                         ic->i_recv_hdrs, ic->i_recv_hdrs_dma);
 604 send_hdrs_dma_out:
 605         ib_dma_free_coherent(dev, ic->i_send_ring.w_nr *
 606                                         sizeof(struct rds_header),
 607                                         ic->i_send_hdrs, ic->i_send_hdrs_dma);
 608 qp_out:
 609         rdma_destroy_qp(ic->i_cm_id);
 610 recv_cq_out:
 611         if (!ib_destroy_cq(ic->i_recv_cq))
 612                 ic->i_recv_cq = NULL;
 613 send_cq_out:
 614         if (!ib_destroy_cq(ic->i_send_cq))
 615                 ic->i_send_cq = NULL;
 616 rds_ibdev_out:
 617         rds_ib_remove_conn(rds_ibdev, conn);
 618 out:
 619         rds_ib_dev_put(rds_ibdev);
 620
 621         return ret;
 622 }
 623
 624 static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event, bool isv6)
 625 {
 626         const union rds_ib_conn_priv *dp = event->param.conn.private_data;
 627         u8 data_len, major, minor;
 628         u32 version = 0;
 629         __be16 mask;
 630         u16 common;
 631
 632         /*
 633          * rdma_cm private data is odd - when there is any private data in the
 634          * request, we will be given a pretty large buffer without telling us the
 635          * original size. The only way to tell the difference is by looking at
 636          * the contents, which are initialized to zero.
 637          * If the protocol version fields aren't set, this is a connection attempt
 638          * from an older version. This could could be 3.0 or 2.0 - we can't tell.
 639          * We really should have changed this for OFED 1.3 :-(
 640          */
 641
 642         /* Be paranoid. RDS always has privdata */
 643         if (!event->param.conn.private_data_len) {
 644                 printk(KERN_NOTICE "RDS incoming connection has no private data, "
 645                         "rejecting\n");
 646                 return 0;
 647         }
 648
 649         if (isv6) {
 650                 data_len = sizeof(struct rds6_ib_connect_private);
 651                 major = dp->ricp_v6.dp_protocol_major;
 652                 minor = dp->ricp_v6.dp_protocol_minor;
 653                 mask = dp->ricp_v6.dp_protocol_minor_mask;
 654         } else {
 655                 data_len = sizeof(struct rds_ib_connect_private);
 656                 major = dp->ricp_v4.dp_protocol_major;
 657                 minor = dp->ricp_v4.dp_protocol_minor;
 658                 mask = dp->ricp_v4.dp_protocol_minor_mask;
 659         }
 660
 661         /* Even if len is crap *now* I still want to check it. -ASG */
 662         if (event->param.conn.private_data_len < data_len || major == 0)
 663                 return RDS_PROTOCOL_4_0;
 664
 665         common = be16_to_cpu(mask) & RDS_IB_SUPPORTED_PROTOCOLS;
 666         if (major == 4 && common) {
 667                 version = RDS_PROTOCOL_4_0;
 668                 while ((common >>= 1) != 0)
 669                         version++;
 670         } else if (RDS_PROTOCOL_COMPAT_VERSION ==
 671                    RDS_PROTOCOL(major, minor)) {
 672                 version = RDS_PROTOCOL_COMPAT_VERSION;
 673         } else {
 674                 if (isv6)
 675                         printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI6c using incompatible protocol version %u.%u\n",
 676                                            &dp->ricp_v6.dp_saddr, major, minor);
 677                 else
 678                         printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
 679                                            &dp->ricp_v4.dp_saddr, major, minor);
 680         }
 681         return version;
 682 }
 683
 684 #if IS_ENABLED(CONFIG_IPV6)
 685 /* Given an IPv6 address, find the net_device which hosts that address and
 686  * return its index.  This is used by the rds_ib_cm_handle_connect() code to
 687  * find the interface index of where an incoming request comes from when
 688  * the request is using a link local address.
 689  *
 690  * Note one problem in this search.  It is possible that two interfaces have
 691  * the same link local address.  Unfortunately, this cannot be solved unless
 692  * the underlying layer gives us the interface which an incoming RDMA connect
 693  * request comes from.
 694  */
 695 static u32 __rds_find_ifindex(struct net *net, const struct in6_addr *addr)
 696 {
 697         struct net_device *dev;
 698         int idx = 0;
 699
 700         rcu_read_lock();
 701         for_each_netdev_rcu(net, dev) {
 702                 if (ipv6_chk_addr(net, addr, dev, 1)) {
 703                         idx = dev->ifindex;
 704                         break;
 705                 }
 706         }
 707         rcu_read_unlock();
 708
 709         return idx;
 710 }
 711 #endif
 712
 713 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
 714                              struct rdma_cm_event *event, bool isv6)
 715 {
 716         __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
 717         __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
 718         const struct rds_ib_conn_priv_cmn *dp_cmn;
 719         struct rds_connection *conn = NULL;
 720         struct rds_ib_connection *ic = NULL;
 721         struct rdma_conn_param conn_param;
 722         const union rds_ib_conn_priv *dp;
 723         union rds_ib_conn_priv dp_rep;
 724         struct in6_addr s_mapped_addr;
 725         struct in6_addr d_mapped_addr;
 726         const struct in6_addr *saddr6;
 727         const struct in6_addr *daddr6;
 728         int destroy = 1;
 729         u32 ifindex = 0;
 730         u32 version;
 731         int err = 1;
 732
 733         /* Check whether the remote protocol version matches ours. */
 734         version = rds_ib_protocol_compatible(event, isv6);
 735         if (!version) {
 736                 err = RDS_RDMA_REJ_INCOMPAT;
 737                 goto out;
 738         }
 739
 740         dp = event->param.conn.private_data;
 741         if (isv6) {
 742 #if IS_ENABLED(CONFIG_IPV6)
 743                 dp_cmn = &dp->ricp_v6.dp_cmn;
 744                 saddr6 = &dp->ricp_v6.dp_saddr;
 745                 daddr6 = &dp->ricp_v6.dp_daddr;
 746                 /* If either address is link local, need to find the
 747                  * interface index in order to create a proper RDS
 748                  * connection.
 749                  */
 750                 if (ipv6_addr_type(daddr6) & IPV6_ADDR_LINKLOCAL) {
 751                         /* Using init_net for now ..  */
 752                         ifindex = __rds_find_ifindex(&init_net, daddr6);
 753                         /* No index found...  Need to bail out. */
 754                         if (ifindex == 0) {
 755                                 err = -EOPNOTSUPP;
 756                                 goto out;
 757                         }
 758                 } else if (ipv6_addr_type(saddr6) & IPV6_ADDR_LINKLOCAL) {
 759                         /* Use our address to find the correct index. */
 760                         ifindex = __rds_find_ifindex(&init_net, daddr6);
 761                         /* No index found...  Need to bail out. */
 762                         if (ifindex == 0) {
 763                                 err = -EOPNOTSUPP;
 764                                 goto out;
 765                         }
 766                 }
 767 #else
 768                 err = -EOPNOTSUPP;
 769                 goto out;
 770 #endif
 771         } else {
 772                 dp_cmn = &dp->ricp_v4.dp_cmn;
 773                 ipv6_addr_set_v4mapped(dp->ricp_v4.dp_saddr, &s_mapped_addr);
 774                 ipv6_addr_set_v4mapped(dp->ricp_v4.dp_daddr, &d_mapped_addr);
 775                 saddr6 = &s_mapped_addr;
 776                 daddr6 = &d_mapped_addr;
 777         }
 778
 779         rdsdebug("saddr %pI6c daddr %pI6c RDSv%u.%u lguid 0x%llx fguid 0x%llx, tos:%d\n",
 780                  saddr6, daddr6, RDS_PROTOCOL_MAJOR(version),
 781                  RDS_PROTOCOL_MINOR(version),
 782                  (unsigned long long)be64_to_cpu(lguid),
 783                  (unsigned long long)be64_to_cpu(fguid), dp_cmn->ricpc_dp_toss);
 784
 785         /* RDS/IB is not currently netns aware, thus init_net */
 786         conn = rds_conn_create(&init_net, daddr6, saddr6,
 787                                &rds_ib_transport, dp_cmn->ricpc_dp_toss,
 788                                GFP_KERNEL, ifindex);
 789         if (IS_ERR(conn)) {
 790                 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
 791                 conn = NULL;
 792                 goto out;
 793         }
 794
 795         /*
 796          * The connection request may occur while the
 797          * previous connection exist, e.g. in case of failover.
 798          * But as connections may be initiated simultaneously
 799          * by both hosts, we have a random backoff mechanism -
 800          * see the comment above rds_queue_reconnect()
 801          */
 802         mutex_lock(&conn->c_cm_lock);
 803         if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
 804                 if (rds_conn_state(conn) == RDS_CONN_UP) {
 805                         rdsdebug("incoming connect while connecting\n");
 806                         rds_conn_drop(conn);
 807                         rds_ib_stats_inc(s_ib_listen_closed_stale);
 808                 } else
 809                 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
 810                         /* Wait and see - our connect may still be succeeding */
 811                         rds_ib_stats_inc(s_ib_connect_raced);
 812                 }
 813                 goto out;
 814         }
 815
 816         ic = conn->c_transport_data;
 817
 818         rds_ib_set_protocol(conn, version);
 819         rds_ib_set_flow_control(conn, be32_to_cpu(dp_cmn->ricpc_credit));
 820
 821         /* If the peer gave us the last packet it saw, process this as if
 822          * we had received a regular ACK. */
 823         if (dp_cmn->ricpc_ack_seq)
 824                 rds_send_drop_acked(conn, be64_to_cpu(dp_cmn->ricpc_ack_seq),
 825                                     NULL);
 826
 827         BUG_ON(cm_id->context);
 828         BUG_ON(ic->i_cm_id);
 829
 830         ic->i_cm_id = cm_id;
 831         cm_id->context = conn;
 832
 833         /* We got halfway through setting up the ib_connection, if we
 834          * fail now, we have to take the long route out of this mess. */
 835         destroy = 0;
 836
 837         err = rds_ib_setup_qp(conn);
 838         if (err) {
 839                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
 840                 goto out;
 841         }
 842
 843         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
 844                                   event->param.conn.responder_resources,
 845                                   event->param.conn.initiator_depth, isv6);
 846
 847         /* rdma_accept() calls rdma_reject() internally if it fails */
 848         if (rdma_accept(cm_id, &conn_param))
 849                 rds_ib_conn_error(conn, "rdma_accept failed\n");
 850
 851 out:
 852         if (conn)
 853                 mutex_unlock(&conn->c_cm_lock);
 854         if (err)
 855                 rdma_reject(cm_id, &err, sizeof(int));
 856         return destroy;
 857 }
 858
 859
 860 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id, bool isv6)
 861 {
 862         struct rds_connection *conn = cm_id->context;
 863         struct rds_ib_connection *ic = conn->c_transport_data;
 864         struct rdma_conn_param conn_param;
 865         union rds_ib_conn_priv dp;
 866         int ret;
 867
 868         /* If the peer doesn't do protocol negotiation, we must
 869          * default to RDSv3.0 */
 870         rds_ib_set_protocol(conn, RDS_PROTOCOL_4_1);
 871         ic->i_flowctl = rds_ib_sysctl_flow_control;     /* advertise flow control */
 872
 873         ret = rds_ib_setup_qp(conn);
 874         if (ret) {
 875                 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
 876                 goto out;
 877         }
 878
 879         rds_ib_cm_fill_conn_param(conn, &conn_param, &dp,
 880                                   conn->c_proposed_version,
 881                                   UINT_MAX, UINT_MAX, isv6);
 882         ret = rdma_connect(cm_id, &conn_param);
 883         if (ret)
 884                 rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
 885
 886 out:
 887         /* Beware - returning non-zero tells the rdma_cm to destroy
 888          * the cm_id. We should certainly not do it as long as we still
 889          * "own" the cm_id. */
 890         if (ret) {
 891                 if (ic->i_cm_id == cm_id)
 892                         ret = 0;
 893         }
 894         ic->i_active_side = true;
 895         return ret;
 896 }
 897
 898 int rds_ib_conn_path_connect(struct rds_conn_path *cp)
 899 {
 900         struct rds_connection *conn = cp->cp_conn;
 901         struct sockaddr_storage src, dest;
 902         rdma_cm_event_handler handler;
 903         struct rds_ib_connection *ic;
 904         int ret;
 905
 906         ic = conn->c_transport_data;
 907
 908         /* XXX I wonder what affect the port space has */
 909         /* delegate cm event handler to rdma_transport */
 910 #if IS_ENABLED(CONFIG_IPV6)
 911         if (conn->c_isv6)
 912                 handler = rds6_rdma_cm_event_handler;
 913         else
 914 #endif
 915                 handler = rds_rdma_cm_event_handler;
 916         ic->i_cm_id = rdma_create_id(&init_net, handler, conn,
 917                                      RDMA_PS_TCP, IB_QPT_RC);
 918         if (IS_ERR(ic->i_cm_id)) {
 919                 ret = PTR_ERR(ic->i_cm_id);
 920                 ic->i_cm_id = NULL;
 921                 rdsdebug("rdma_create_id() failed: %d\n", ret);
 922                 goto out;
 923         }
 924
 925         rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
 926
 927         if (ipv6_addr_v4mapped(&conn->c_faddr)) {
 928                 struct sockaddr_in *sin;
 929
 930                 sin = (struct sockaddr_in *)&src;
 931                 sin->sin_family = AF_INET;
 932                 sin->sin_addr.s_addr = conn->c_laddr.s6_addr32[3];
 933                 sin->sin_port = 0;
 934
 935                 sin = (struct sockaddr_in *)&dest;
 936                 sin->sin_family = AF_INET;
 937                 sin->sin_addr.s_addr = conn->c_faddr.s6_addr32[3];
 938                 sin->sin_port = htons(RDS_PORT);
 939         } else {
 940                 struct sockaddr_in6 *sin6;
 941
 942                 sin6 = (struct sockaddr_in6 *)&src;
 943                 sin6->sin6_family = AF_INET6;
 944                 sin6->sin6_addr = conn->c_laddr;
 945                 sin6->sin6_port = 0;
 946                 sin6->sin6_scope_id = conn->c_dev_if;
 947
 948                 sin6 = (struct sockaddr_in6 *)&dest;
 949                 sin6->sin6_family = AF_INET6;
 950                 sin6->sin6_addr = conn->c_faddr;
 951                 sin6->sin6_port = htons(RDS_CM_PORT);
 952                 sin6->sin6_scope_id = conn->c_dev_if;
 953         }
 954
 955         ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
 956                                 (struct sockaddr *)&dest,
 957                                 RDS_RDMA_RESOLVE_TIMEOUT_MS);
 958         if (ret) {
 959                 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
 960                          ret);
 961                 rdma_destroy_id(ic->i_cm_id);
 962                 ic->i_cm_id = NULL;
 963         }
 964
 965 out:
 966         return ret;
 967 }
 968
 969 /*
 970  * This is so careful about only cleaning up resources that were built up
 971  * so that it can be called at any point during startup.  In fact it
 972  * can be called multiple times for a given connection.
 973  */
 974 void rds_ib_conn_path_shutdown(struct rds_conn_path *cp)
 975 {
 976         struct rds_connection *conn = cp->cp_conn;
 977         struct rds_ib_connection *ic = conn->c_transport_data;
 978         int err = 0;
 979
 980         rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
 981                  ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
 982                  ic->i_cm_id ? ic->i_cm_id->qp : NULL);
 983
 984         if (ic->i_cm_id) {
 985                 struct ib_device *dev = ic->i_cm_id->device;
 986
 987                 rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
 988                 err = rdma_disconnect(ic->i_cm_id);
 989                 if (err) {
 990                         /* Actually this may happen quite frequently, when
 991                          * an outgoing connect raced with an incoming connect.
 992                          */
 993                         rdsdebug("failed to disconnect, cm: %p err %d\n",
 994                                 ic->i_cm_id, err);
 995                 }
 996
 997                 /* kick off "flush_worker" for all pools in order to reap
 998                  * all FRMR registrations that are still marked "FRMR_IS_INUSE"
 999                  */
1000                 rds_ib_flush_mrs();
1001
1002                 /*
1003                  * We want to wait for tx and rx completion to finish
1004                  * before we tear down the connection, but we have to be
1005                  * careful not to get stuck waiting on a send ring that
1006                  * only has unsignaled sends in it.  We've shutdown new
1007                  * sends before getting here so by waiting for signaled
1008                  * sends to complete we're ensured that there will be no
1009                  * more tx processing.
1010                  */
1011                 wait_event(rds_ib_ring_empty_wait,
1012                            rds_ib_ring_empty(&ic->i_recv_ring) &&
1013                            (atomic_read(&ic->i_signaled_sends) == 0) &&
1014                            (atomic_read(&ic->i_fastreg_inuse_count) == 0) &&
1015                            (atomic_read(&ic->i_fastreg_wrs) == RDS_IB_DEFAULT_FR_WR));
1016                 tasklet_kill(&ic->i_send_tasklet);
1017                 tasklet_kill(&ic->i_recv_tasklet);
1018
1019                 atomic_set(&ic->i_cq_quiesce, 1);
1020
1021                 /* first destroy the ib state that generates callbacks */
1022                 if (ic->i_cm_id->qp)
1023                         rdma_destroy_qp(ic->i_cm_id);
1024                 if (ic->i_send_cq) {
1025                         if (ic->rds_ibdev)
1026                                 ibdev_put_vector(ic->rds_ibdev, ic->i_scq_vector);
1027                         ib_destroy_cq(ic->i_send_cq);
1028                 }
1029
1030                 if (ic->i_recv_cq) {
1031                         if (ic->rds_ibdev)
1032                                 ibdev_put_vector(ic->rds_ibdev, ic->i_rcq_vector);
1033                         ib_destroy_cq(ic->i_recv_cq);
1034                 }
1035
1036                 /* then free the resources that ib callbacks use */
1037                 if (ic->i_send_hdrs)
1038                         ib_dma_free_coherent(dev,
1039                                            ic->i_send_ring.w_nr *
1040                                                 sizeof(struct rds_header),
1041                                            ic->i_send_hdrs,
1042                                            ic->i_send_hdrs_dma);
1043
1044                 if (ic->i_recv_hdrs)
1045                         ib_dma_free_coherent(dev,
1046                                            ic->i_recv_ring.w_nr *
1047                                                 sizeof(struct rds_header),
1048                                            ic->i_recv_hdrs,
1049                                            ic->i_recv_hdrs_dma);
1050
1051                 if (ic->i_ack)
1052                         ib_dma_free_coherent(dev, sizeof(struct rds_header),
1053                                              ic->i_ack, ic->i_ack_dma);
1054
1055                 if (ic->i_sends)
1056                         rds_ib_send_clear_ring(ic);
1057                 if (ic->i_recvs)
1058                         rds_ib_recv_clear_ring(ic);
1059
1060                 rdma_destroy_id(ic->i_cm_id);
1061
1062                 /*
1063                  * Move connection back to the nodev list.
1064                  */
1065                 if (ic->rds_ibdev)
1066                         rds_ib_remove_conn(ic->rds_ibdev, conn);
1067
1068                 ic->i_cm_id = NULL;
1069                 ic->i_pd = NULL;
1070                 ic->i_send_cq = NULL;
1071                 ic->i_recv_cq = NULL;
1072                 ic->i_send_hdrs = NULL;
1073                 ic->i_recv_hdrs = NULL;
1074                 ic->i_ack = NULL;
1075         }
1076         BUG_ON(ic->rds_ibdev);
1077
1078         /* Clear pending transmit */
1079         if (ic->i_data_op) {
1080                 struct rds_message *rm;
1081
1082                 rm = container_of(ic->i_data_op, struct rds_message, data);
1083                 rds_message_put(rm);
1084                 ic->i_data_op = NULL;
1085         }
1086
1087         /* Clear the ACK state */
1088         clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
1089 #ifdef KERNEL_HAS_ATOMIC64
1090         atomic64_set(&ic->i_ack_next, 0);
1091 #else
1092         ic->i_ack_next = 0;
1093 #endif
1094         ic->i_ack_recv = 0;
1095
1096         /* Clear flow control state */
1097         ic->i_flowctl = 0;
1098         atomic_set(&ic->i_credits, 0);
1099
1100         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
1101         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
1102
1103         if (ic->i_ibinc) {
1104                 rds_inc_put(&ic->i_ibinc->ii_inc);
1105                 ic->i_ibinc = NULL;
1106         }
1107
1108         vfree(ic->i_sends);
1109         ic->i_sends = NULL;
1110         vfree(ic->i_recvs);
1111         ic->i_recvs = NULL;
1112         ic->i_active_side = false;
1113 }
1114
1115 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
1116 {
1117         struct rds_ib_connection *ic;
1118         unsigned long flags;
1119         int ret;
1120
1121         /* XXX too lazy? */
1122         ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
1123         if (!ic)
1124                 return -ENOMEM;
1125
1126         ret = rds_ib_recv_alloc_caches(ic, gfp);
1127         if (ret) {
1128                 kfree(ic);
1129                 return ret;
1130         }
1131
1132         INIT_LIST_HEAD(&ic->ib_node);
1133         tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send,
1134                      (unsigned long)ic);
1135         tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
1136                      (unsigned long)ic);
1137         mutex_init(&ic->i_recv_mutex);
1138 #ifndef KERNEL_HAS_ATOMIC64
1139         spin_lock_init(&ic->i_ack_lock);
1140 #endif
1141         atomic_set(&ic->i_signaled_sends, 0);
1142
1143         /*
1144          * rds_ib_conn_shutdown() waits for these to be emptied so they
1145          * must be initialized before it can be called.
1146          */
1147         rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
1148         rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
1149
1150         ic->conn = conn;
1151         conn->c_transport_data = ic;
1152
1153         spin_lock_irqsave(&ib_nodev_conns_lock, flags);
1154         list_add_tail(&ic->ib_node, &ib_nodev_conns);
1155         spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
1156
1157
1158         rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
1159         return 0;
1160 }
1161
1162 /*
1163  * Free a connection. Connection must be shut down and not set for reconnect.
1164  */
1165 void rds_ib_conn_free(void *arg)
1166 {
1167         struct rds_ib_connection *ic = arg;
1168         spinlock_t      *lock_ptr;
1169
1170         rdsdebug("ic %p\n", ic);
1171
1172         /*
1173          * Conn is either on a dev's list or on the nodev list.
1174          * A race with shutdown() or connect() would cause problems
1175          * (since rds_ibdev would change) but that should never happen.
1176          */
1177         lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
1178
1179         spin_lock_irq(lock_ptr);
1180         list_del(&ic->ib_node);
1181         spin_unlock_irq(lock_ptr);
1182
1183         rds_ib_recv_free_caches(ic);
1184
1185         kfree(ic);
1186 }
1187
1188
1189 /*
1190  * An error occurred on the connection
1191  */
1192 void
1193 __rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
1194 {
1195         va_list ap;
1196
1197         rds_conn_drop(conn);
1198
1199         va_start(ap, fmt);
1200         vprintk(fmt, ap);
1201         va_end(ap);
1202 }