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