1 /* 2 * Copyright (c) 2006 Oracle. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 * 32 */ 33 #include <linux/kernel.h> 34 #include <linux/in.h> 35 #include <linux/slab.h> 36 #include <linux/vmalloc.h> 37 #include <linux/ratelimit.h> 38 39 #include "rds_single_path.h" 40 #include "rds.h" 41 #include "ib.h" 42 43 /* 44 * Set the selected protocol version 45 */ 46 static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version) 47 { 48 conn->c_version = version; 49 } 50 51 /* 52 * Set up flow control 53 */ 54 static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits) 55 { 56 struct rds_ib_connection *ic = conn->c_transport_data; 57 58 if (rds_ib_sysctl_flow_control && credits != 0) { 59 /* We're doing flow control */ 60 ic->i_flowctl = 1; 61 rds_ib_send_add_credits(conn, credits); 62 } else { 63 ic->i_flowctl = 0; 64 } 65 } 66 67 /* 68 * Tune RNR behavior. Without flow control, we use a rather 69 * low timeout, but not the absolute minimum - this should 70 * be tunable. 71 * 72 * We already set the RNR retry count to 7 (which is the 73 * smallest infinite number :-) above. 74 * If flow control is off, we want to change this back to 0 75 * so that we learn quickly when our credit accounting is 76 * buggy. 77 * 78 * Caller passes in a qp_attr pointer - don't waste stack spacv 79 * by allocation this twice. 80 */ 81 static void 82 rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr) 83 { 84 int ret; 85 86 attr->min_rnr_timer = IB_RNR_TIMER_000_32; 87 ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER); 88 if (ret) 89 printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret); 90 } 91 92 /* 93 * Connection established. 94 * We get here for both outgoing and incoming connection. 95 */ 96 void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event) 97 { 98 const struct rds_ib_connect_private *dp = NULL; 99 struct rds_ib_connection *ic = conn->c_transport_data; 100 struct ib_qp_attr qp_attr; 101 int err; 102 103 if (event->param.conn.private_data_len >= sizeof(*dp)) { 104 dp = event->param.conn.private_data; 105 106 /* make sure it isn't empty data */ 107 if (dp->dp_protocol_major) { 108 rds_ib_set_protocol(conn, 109 RDS_PROTOCOL(dp->dp_protocol_major, 110 dp->dp_protocol_minor)); 111 rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit)); 112 } 113 } 114 115 if (conn->c_version < RDS_PROTOCOL(3, 1)) { 116 pr_notice("RDS/IB: Connection <%pI4,%pI4> version %u.%u no longer supported\n", 117 &conn->c_laddr, &conn->c_faddr, 118 RDS_PROTOCOL_MAJOR(conn->c_version), 119 RDS_PROTOCOL_MINOR(conn->c_version)); 120 set_bit(RDS_DESTROY_PENDING, &conn->c_path[0].cp_flags); 121 rds_conn_destroy(conn); 122 return; 123 } else { 124 pr_notice("RDS/IB: %s conn connected <%pI4,%pI4> version %u.%u%s\n", 125 ic->i_active_side ? "Active" : "Passive", 126 &conn->c_laddr, &conn->c_faddr, 127 RDS_PROTOCOL_MAJOR(conn->c_version), 128 RDS_PROTOCOL_MINOR(conn->c_version), 129 ic->i_flowctl ? ", flow control" : ""); 130 } 131 132 atomic_set(&ic->i_cq_quiesce, 0); 133 134 /* Init rings and fill recv. this needs to wait until protocol 135 * negotiation is complete, since ring layout is different 136 * from 3.1 to 4.1. 137 */ 138 rds_ib_send_init_ring(ic); 139 rds_ib_recv_init_ring(ic); 140 /* Post receive buffers - as a side effect, this will update 141 * the posted credit count. */ 142 rds_ib_recv_refill(conn, 1, GFP_KERNEL); 143 144 /* Tune RNR behavior */ 145 rds_ib_tune_rnr(ic, &qp_attr); 146 147 qp_attr.qp_state = IB_QPS_RTS; 148 err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE); 149 if (err) 150 printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err); 151 152 /* update ib_device with this local ipaddr */ 153 err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr); 154 if (err) 155 printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n", 156 err); 157 158 /* If the peer gave us the last packet it saw, process this as if 159 * we had received a regular ACK. */ 160 if (dp) { 161 /* dp structure start is not guaranteed to be 8 bytes aligned. 162 * Since dp_ack_seq is 64-bit extended load operations can be 163 * used so go through get_unaligned to avoid unaligned errors. 164 */ 165 __be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq); 166 167 if (dp_ack_seq) 168 rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq), 169 NULL); 170 } 171 172 rds_connect_complete(conn); 173 } 174 175 static void rds_ib_cm_fill_conn_param(struct rds_connection *conn, 176 struct rdma_conn_param *conn_param, 177 struct rds_ib_connect_private *dp, 178 u32 protocol_version, 179 u32 max_responder_resources, 180 u32 max_initiator_depth) 181 { 182 struct rds_ib_connection *ic = conn->c_transport_data; 183 struct rds_ib_device *rds_ibdev = ic->rds_ibdev; 184 185 memset(conn_param, 0, sizeof(struct rdma_conn_param)); 186 187 conn_param->responder_resources = 188 min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources); 189 conn_param->initiator_depth = 190 min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth); 191 conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7); 192 conn_param->rnr_retry_count = 7; 193 194 if (dp) { 195 memset(dp, 0, sizeof(*dp)); 196 dp->dp_saddr = conn->c_laddr; 197 dp->dp_daddr = conn->c_faddr; 198 dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version); 199 dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version); 200 dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS); 201 dp->dp_ack_seq = cpu_to_be64(rds_ib_piggyb_ack(ic)); 202 203 /* Advertise flow control */ 204 if (ic->i_flowctl) { 205 unsigned int credits; 206 207 credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits)); 208 dp->dp_credit = cpu_to_be32(credits); 209 atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits); 210 } 211 212 conn_param->private_data = dp; 213 conn_param->private_data_len = sizeof(*dp); 214 } 215 } 216 217 static void rds_ib_cq_event_handler(struct ib_event *event, void *data) 218 { 219 rdsdebug("event %u (%s) data %p\n", 220 event->event, ib_event_msg(event->event), data); 221 } 222 223 /* Plucking the oldest entry from the ring can be done concurrently with 224 * the thread refilling the ring. Each ring operation is protected by 225 * spinlocks and the transient state of refilling doesn't change the 226 * recording of which entry is oldest. 227 * 228 * This relies on IB only calling one cq comp_handler for each cq so that 229 * there will only be one caller of rds_recv_incoming() per RDS connection. 230 */ 231 static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context) 232 { 233 struct rds_connection *conn = context; 234 struct rds_ib_connection *ic = conn->c_transport_data; 235 236 rdsdebug("conn %p cq %p\n", conn, cq); 237 238 rds_ib_stats_inc(s_ib_evt_handler_call); 239 240 tasklet_schedule(&ic->i_recv_tasklet); 241 } 242 243 static void poll_scq(struct rds_ib_connection *ic, struct ib_cq *cq, 244 struct ib_wc *wcs) 245 { 246 int nr, i; 247 struct ib_wc *wc; 248 249 while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) { 250 for (i = 0; i < nr; i++) { 251 wc = wcs + i; 252 rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n", 253 (unsigned long long)wc->wr_id, wc->status, 254 wc->byte_len, be32_to_cpu(wc->ex.imm_data)); 255 256 if (wc->wr_id <= ic->i_send_ring.w_nr || 257 wc->wr_id == RDS_IB_ACK_WR_ID) 258 rds_ib_send_cqe_handler(ic, wc); 259 else 260 rds_ib_mr_cqe_handler(ic, wc); 261 262 } 263 } 264 } 265 266 static void rds_ib_tasklet_fn_send(unsigned long data) 267 { 268 struct rds_ib_connection *ic = (struct rds_ib_connection *)data; 269 struct rds_connection *conn = ic->conn; 270 271 rds_ib_stats_inc(s_ib_tasklet_call); 272 273 /* if cq has been already reaped, ignore incoming cq event */ 274 if (atomic_read(&ic->i_cq_quiesce)) 275 return; 276 277 poll_scq(ic, ic->i_send_cq, ic->i_send_wc); 278 ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP); 279 poll_scq(ic, ic->i_send_cq, ic->i_send_wc); 280 281 if (rds_conn_up(conn) && 282 (!test_bit(RDS_LL_SEND_FULL, &conn->c_flags) || 283 test_bit(0, &conn->c_map_queued))) 284 rds_send_xmit(&ic->conn->c_path[0]); 285 } 286 287 static void poll_rcq(struct rds_ib_connection *ic, struct ib_cq *cq, 288 struct ib_wc *wcs, 289 struct rds_ib_ack_state *ack_state) 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 rds_ib_recv_cqe_handler(ic, wc, ack_state); 302 } 303 } 304 } 305 306 static void rds_ib_tasklet_fn_recv(unsigned long data) 307 { 308 struct rds_ib_connection *ic = (struct rds_ib_connection *)data; 309 struct rds_connection *conn = ic->conn; 310 struct rds_ib_device *rds_ibdev = ic->rds_ibdev; 311 struct rds_ib_ack_state state; 312 313 if (!rds_ibdev) 314 rds_conn_drop(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 memset(&state, 0, sizeof(state)); 323 poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state); 324 ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED); 325 poll_rcq(ic, ic->i_recv_cq, ic->i_recv_wc, &state); 326 327 if (state.ack_next_valid) 328 rds_ib_set_ack(ic, state.ack_next, state.ack_required); 329 if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) { 330 rds_send_drop_acked(conn, state.ack_recv, NULL); 331 ic->i_ack_recv = state.ack_recv; 332 } 333 334 if (rds_conn_up(conn)) 335 rds_ib_attempt_ack(ic); 336 } 337 338 static void rds_ib_qp_event_handler(struct ib_event *event, void *data) 339 { 340 struct rds_connection *conn = data; 341 struct rds_ib_connection *ic = conn->c_transport_data; 342 343 rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event, 344 ib_event_msg(event->event)); 345 346 switch (event->event) { 347 case IB_EVENT_COMM_EST: 348 rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST); 349 break; 350 default: 351 rdsdebug("Fatal QP Event %u (%s) " 352 "- connection %pI4->%pI4, reconnecting\n", 353 event->event, ib_event_msg(event->event), 354 &conn->c_laddr, &conn->c_faddr); 355 rds_conn_drop(conn); 356 break; 357 } 358 } 359 360 static void rds_ib_cq_comp_handler_send(struct ib_cq *cq, void *context) 361 { 362 struct rds_connection *conn = context; 363 struct rds_ib_connection *ic = conn->c_transport_data; 364 365 rdsdebug("conn %p cq %p\n", conn, cq); 366 367 rds_ib_stats_inc(s_ib_evt_handler_call); 368 369 tasklet_schedule(&ic->i_send_tasklet); 370 } 371 372 static inline int ibdev_get_unused_vector(struct rds_ib_device *rds_ibdev) 373 { 374 int min = rds_ibdev->vector_load[rds_ibdev->dev->num_comp_vectors - 1]; 375 int index = rds_ibdev->dev->num_comp_vectors - 1; 376 int i; 377 378 for (i = rds_ibdev->dev->num_comp_vectors - 1; i >= 0; i--) { 379 if (rds_ibdev->vector_load[i] < min) { 380 index = i; 381 min = rds_ibdev->vector_load[i]; 382 } 383 } 384 385 rds_ibdev->vector_load[index]++; 386 return index; 387 } 388 389 static inline void ibdev_put_vector(struct rds_ib_device *rds_ibdev, int index) 390 { 391 rds_ibdev->vector_load[index]--; 392 } 393 394 /* 395 * This needs to be very careful to not leave IS_ERR pointers around for 396 * cleanup to trip over. 397 */ 398 static int rds_ib_setup_qp(struct rds_connection *conn) 399 { 400 struct rds_ib_connection *ic = conn->c_transport_data; 401 struct ib_device *dev = ic->i_cm_id->device; 402 struct ib_qp_init_attr attr; 403 struct ib_cq_init_attr cq_attr = {}; 404 struct rds_ib_device *rds_ibdev; 405 int ret, fr_queue_space; 406 407 /* 408 * It's normal to see a null device if an incoming connection races 409 * with device removal, so we don't print a warning. 410 */ 411 rds_ibdev = rds_ib_get_client_data(dev); 412 if (!rds_ibdev) 413 return -EOPNOTSUPP; 414 415 /* The fr_queue_space is currently set to 512, to add extra space on 416 * completion queue and send queue. This extra space is used for FRMR 417 * registration and invalidation work requests 418 */ 419 fr_queue_space = rds_ibdev->use_fastreg ? 420 (RDS_IB_DEFAULT_FR_WR + 1) + 421 (RDS_IB_DEFAULT_FR_INV_WR + 1) 422 : 0; 423 424 /* add the conn now so that connection establishment has the dev */ 425 rds_ib_add_conn(rds_ibdev, conn); 426 427 if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1) 428 rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1); 429 if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1) 430 rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1); 431 432 /* Protection domain and memory range */ 433 ic->i_pd = rds_ibdev->pd; 434 435 ic->i_scq_vector = ibdev_get_unused_vector(rds_ibdev); 436 cq_attr.cqe = ic->i_send_ring.w_nr + fr_queue_space + 1; 437 cq_attr.comp_vector = ic->i_scq_vector; 438 ic->i_send_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_send, 439 rds_ib_cq_event_handler, conn, 440 &cq_attr); 441 if (IS_ERR(ic->i_send_cq)) { 442 ret = PTR_ERR(ic->i_send_cq); 443 ic->i_send_cq = NULL; 444 ibdev_put_vector(rds_ibdev, ic->i_scq_vector); 445 rdsdebug("ib_create_cq send failed: %d\n", ret); 446 goto rds_ibdev_out; 447 } 448 449 ic->i_rcq_vector = ibdev_get_unused_vector(rds_ibdev); 450 cq_attr.cqe = ic->i_recv_ring.w_nr; 451 cq_attr.comp_vector = ic->i_rcq_vector; 452 ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv, 453 rds_ib_cq_event_handler, conn, 454 &cq_attr); 455 if (IS_ERR(ic->i_recv_cq)) { 456 ret = PTR_ERR(ic->i_recv_cq); 457 ic->i_recv_cq = NULL; 458 ibdev_put_vector(rds_ibdev, ic->i_rcq_vector); 459 rdsdebug("ib_create_cq recv failed: %d\n", ret); 460 goto send_cq_out; 461 } 462 463 ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP); 464 if (ret) { 465 rdsdebug("ib_req_notify_cq send failed: %d\n", ret); 466 goto recv_cq_out; 467 } 468 469 ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED); 470 if (ret) { 471 rdsdebug("ib_req_notify_cq recv failed: %d\n", ret); 472 goto recv_cq_out; 473 } 474 475 /* XXX negotiate max send/recv with remote? */ 476 memset(&attr, 0, sizeof(attr)); 477 attr.event_handler = rds_ib_qp_event_handler; 478 attr.qp_context = conn; 479 /* + 1 to allow for the single ack message */ 480 attr.cap.max_send_wr = ic->i_send_ring.w_nr + fr_queue_space + 1; 481 attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1; 482 attr.cap.max_send_sge = rds_ibdev->max_sge; 483 attr.cap.max_recv_sge = RDS_IB_RECV_SGE; 484 attr.sq_sig_type = IB_SIGNAL_REQ_WR; 485 attr.qp_type = IB_QPT_RC; 486 attr.send_cq = ic->i_send_cq; 487 attr.recv_cq = ic->i_recv_cq; 488 atomic_set(&ic->i_fastreg_wrs, RDS_IB_DEFAULT_FR_WR); 489 atomic_set(&ic->i_fastunreg_wrs, RDS_IB_DEFAULT_FR_INV_WR); 490 491 /* 492 * XXX this can fail if max_*_wr is too large? Are we supposed 493 * to back off until we get a value that the hardware can support? 494 */ 495 ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr); 496 if (ret) { 497 rdsdebug("rdma_create_qp failed: %d\n", ret); 498 goto recv_cq_out; 499 } 500 501 ic->i_send_hdrs = ib_dma_alloc_coherent(dev, 502 ic->i_send_ring.w_nr * 503 sizeof(struct rds_header), 504 &ic->i_send_hdrs_dma, GFP_KERNEL); 505 if (!ic->i_send_hdrs) { 506 ret = -ENOMEM; 507 rdsdebug("ib_dma_alloc_coherent send failed\n"); 508 goto qp_out; 509 } 510 511 ic->i_recv_hdrs = ib_dma_alloc_coherent(dev, 512 ic->i_recv_ring.w_nr * 513 sizeof(struct rds_header), 514 &ic->i_recv_hdrs_dma, GFP_KERNEL); 515 if (!ic->i_recv_hdrs) { 516 ret = -ENOMEM; 517 rdsdebug("ib_dma_alloc_coherent recv failed\n"); 518 goto send_hdrs_dma_out; 519 } 520 521 ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header), 522 &ic->i_ack_dma, GFP_KERNEL); 523 if (!ic->i_ack) { 524 ret = -ENOMEM; 525 rdsdebug("ib_dma_alloc_coherent ack failed\n"); 526 goto recv_hdrs_dma_out; 527 } 528 529 ic->i_sends = vzalloc_node(array_size(sizeof(struct rds_ib_send_work), 530 ic->i_send_ring.w_nr), 531 ibdev_to_node(dev)); 532 if (!ic->i_sends) { 533 ret = -ENOMEM; 534 rdsdebug("send allocation failed\n"); 535 goto ack_dma_out; 536 } 537 538 ic->i_recvs = vzalloc_node(array_size(sizeof(struct rds_ib_recv_work), 539 ic->i_recv_ring.w_nr), 540 ibdev_to_node(dev)); 541 if (!ic->i_recvs) { 542 ret = -ENOMEM; 543 rdsdebug("recv allocation failed\n"); 544 goto sends_out; 545 } 546 547 rds_ib_recv_init_ack(ic); 548 549 rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd, 550 ic->i_send_cq, ic->i_recv_cq); 551 552 goto out; 553 554 sends_out: 555 vfree(ic->i_sends); 556 ack_dma_out: 557 ib_dma_free_coherent(dev, sizeof(struct rds_header), 558 ic->i_ack, ic->i_ack_dma); 559 recv_hdrs_dma_out: 560 ib_dma_free_coherent(dev, ic->i_recv_ring.w_nr * 561 sizeof(struct rds_header), 562 ic->i_recv_hdrs, ic->i_recv_hdrs_dma); 563 send_hdrs_dma_out: 564 ib_dma_free_coherent(dev, ic->i_send_ring.w_nr * 565 sizeof(struct rds_header), 566 ic->i_send_hdrs, ic->i_send_hdrs_dma); 567 qp_out: 568 rdma_destroy_qp(ic->i_cm_id); 569 recv_cq_out: 570 if (!ib_destroy_cq(ic->i_recv_cq)) 571 ic->i_recv_cq = NULL; 572 send_cq_out: 573 if (!ib_destroy_cq(ic->i_send_cq)) 574 ic->i_send_cq = NULL; 575 rds_ibdev_out: 576 rds_ib_remove_conn(rds_ibdev, conn); 577 out: 578 rds_ib_dev_put(rds_ibdev); 579 580 return ret; 581 } 582 583 static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event) 584 { 585 const struct rds_ib_connect_private *dp = event->param.conn.private_data; 586 u16 common; 587 u32 version = 0; 588 589 /* 590 * rdma_cm private data is odd - when there is any private data in the 591 * request, we will be given a pretty large buffer without telling us the 592 * original size. The only way to tell the difference is by looking at 593 * the contents, which are initialized to zero. 594 * If the protocol version fields aren't set, this is a connection attempt 595 * from an older version. This could could be 3.0 or 2.0 - we can't tell. 596 * We really should have changed this for OFED 1.3 :-( 597 */ 598 599 /* Be paranoid. RDS always has privdata */ 600 if (!event->param.conn.private_data_len) { 601 printk(KERN_NOTICE "RDS incoming connection has no private data, " 602 "rejecting\n"); 603 return 0; 604 } 605 606 /* Even if len is crap *now* I still want to check it. -ASG */ 607 if (event->param.conn.private_data_len < sizeof (*dp) || 608 dp->dp_protocol_major == 0) 609 return RDS_PROTOCOL_3_0; 610 611 common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS; 612 if (dp->dp_protocol_major == 3 && common) { 613 version = RDS_PROTOCOL_3_0; 614 while ((common >>= 1) != 0) 615 version++; 616 } else 617 printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n", 618 &dp->dp_saddr, 619 dp->dp_protocol_major, 620 dp->dp_protocol_minor); 621 return version; 622 } 623 624 int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id, 625 struct rdma_cm_event *event) 626 { 627 __be64 lguid = cm_id->route.path_rec->sgid.global.interface_id; 628 __be64 fguid = cm_id->route.path_rec->dgid.global.interface_id; 629 const struct rds_ib_connect_private *dp = event->param.conn.private_data; 630 struct rds_ib_connect_private dp_rep; 631 struct rds_connection *conn = NULL; 632 struct rds_ib_connection *ic = NULL; 633 struct rdma_conn_param conn_param; 634 u32 version; 635 int err = 1, destroy = 1; 636 637 /* Check whether the remote protocol version matches ours. */ 638 version = rds_ib_protocol_compatible(event); 639 if (!version) 640 goto out; 641 642 rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid " 643 "0x%llx\n", &dp->dp_saddr, &dp->dp_daddr, 644 RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version), 645 (unsigned long long)be64_to_cpu(lguid), 646 (unsigned long long)be64_to_cpu(fguid)); 647 648 /* RDS/IB is not currently netns aware, thus init_net */ 649 conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr, 650 &rds_ib_transport, GFP_KERNEL); 651 if (IS_ERR(conn)) { 652 rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn)); 653 conn = NULL; 654 goto out; 655 } 656 657 /* 658 * The connection request may occur while the 659 * previous connection exist, e.g. in case of failover. 660 * But as connections may be initiated simultaneously 661 * by both hosts, we have a random backoff mechanism - 662 * see the comment above rds_queue_reconnect() 663 */ 664 mutex_lock(&conn->c_cm_lock); 665 if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) { 666 if (rds_conn_state(conn) == RDS_CONN_UP) { 667 rdsdebug("incoming connect while connecting\n"); 668 rds_conn_drop(conn); 669 rds_ib_stats_inc(s_ib_listen_closed_stale); 670 } else 671 if (rds_conn_state(conn) == RDS_CONN_CONNECTING) { 672 /* Wait and see - our connect may still be succeeding */ 673 rds_ib_stats_inc(s_ib_connect_raced); 674 } 675 goto out; 676 } 677 678 ic = conn->c_transport_data; 679 680 rds_ib_set_protocol(conn, version); 681 rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit)); 682 683 /* If the peer gave us the last packet it saw, process this as if 684 * we had received a regular ACK. */ 685 if (dp->dp_ack_seq) 686 rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL); 687 688 BUG_ON(cm_id->context); 689 BUG_ON(ic->i_cm_id); 690 691 ic->i_cm_id = cm_id; 692 cm_id->context = conn; 693 694 /* We got halfway through setting up the ib_connection, if we 695 * fail now, we have to take the long route out of this mess. */ 696 destroy = 0; 697 698 err = rds_ib_setup_qp(conn); 699 if (err) { 700 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err); 701 goto out; 702 } 703 704 rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version, 705 event->param.conn.responder_resources, 706 event->param.conn.initiator_depth); 707 708 /* rdma_accept() calls rdma_reject() internally if it fails */ 709 if (rdma_accept(cm_id, &conn_param)) 710 rds_ib_conn_error(conn, "rdma_accept failed\n"); 711 712 out: 713 if (conn) 714 mutex_unlock(&conn->c_cm_lock); 715 if (err) 716 rdma_reject(cm_id, NULL, 0); 717 return destroy; 718 } 719 720 721 int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id) 722 { 723 struct rds_connection *conn = cm_id->context; 724 struct rds_ib_connection *ic = conn->c_transport_data; 725 struct rdma_conn_param conn_param; 726 struct rds_ib_connect_private dp; 727 int ret; 728 729 /* If the peer doesn't do protocol negotiation, we must 730 * default to RDSv3.0 */ 731 rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0); 732 ic->i_flowctl = rds_ib_sysctl_flow_control; /* advertise flow control */ 733 734 ret = rds_ib_setup_qp(conn); 735 if (ret) { 736 rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret); 737 goto out; 738 } 739 740 rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION, 741 UINT_MAX, UINT_MAX); 742 ret = rdma_connect(cm_id, &conn_param); 743 if (ret) 744 rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret); 745 746 out: 747 /* Beware - returning non-zero tells the rdma_cm to destroy 748 * the cm_id. We should certainly not do it as long as we still 749 * "own" the cm_id. */ 750 if (ret) { 751 if (ic->i_cm_id == cm_id) 752 ret = 0; 753 } 754 ic->i_active_side = true; 755 return ret; 756 } 757 758 int rds_ib_conn_path_connect(struct rds_conn_path *cp) 759 { 760 struct rds_connection *conn = cp->cp_conn; 761 struct rds_ib_connection *ic = conn->c_transport_data; 762 struct sockaddr_in src, dest; 763 int ret; 764 765 /* XXX I wonder what affect the port space has */ 766 /* delegate cm event handler to rdma_transport */ 767 ic->i_cm_id = rdma_create_id(&init_net, rds_rdma_cm_event_handler, conn, 768 RDMA_PS_TCP, IB_QPT_RC); 769 if (IS_ERR(ic->i_cm_id)) { 770 ret = PTR_ERR(ic->i_cm_id); 771 ic->i_cm_id = NULL; 772 rdsdebug("rdma_create_id() failed: %d\n", ret); 773 goto out; 774 } 775 776 rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn); 777 778 src.sin_family = AF_INET; 779 src.sin_addr.s_addr = (__force u32)conn->c_laddr; 780 src.sin_port = (__force u16)htons(0); 781 782 dest.sin_family = AF_INET; 783 dest.sin_addr.s_addr = (__force u32)conn->c_faddr; 784 dest.sin_port = (__force u16)htons(RDS_PORT); 785 786 ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src, 787 (struct sockaddr *)&dest, 788 RDS_RDMA_RESOLVE_TIMEOUT_MS); 789 if (ret) { 790 rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id, 791 ret); 792 rdma_destroy_id(ic->i_cm_id); 793 ic->i_cm_id = NULL; 794 } 795 796 out: 797 return ret; 798 } 799 800 /* 801 * This is so careful about only cleaning up resources that were built up 802 * so that it can be called at any point during startup. In fact it 803 * can be called multiple times for a given connection. 804 */ 805 void rds_ib_conn_path_shutdown(struct rds_conn_path *cp) 806 { 807 struct rds_connection *conn = cp->cp_conn; 808 struct rds_ib_connection *ic = conn->c_transport_data; 809 int err = 0; 810 811 rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id, 812 ic->i_pd, ic->i_send_cq, ic->i_recv_cq, 813 ic->i_cm_id ? ic->i_cm_id->qp : NULL); 814 815 if (ic->i_cm_id) { 816 struct ib_device *dev = ic->i_cm_id->device; 817 818 rdsdebug("disconnecting cm %p\n", ic->i_cm_id); 819 err = rdma_disconnect(ic->i_cm_id); 820 if (err) { 821 /* Actually this may happen quite frequently, when 822 * an outgoing connect raced with an incoming connect. 823 */ 824 rdsdebug("failed to disconnect, cm: %p err %d\n", 825 ic->i_cm_id, err); 826 } 827 828 /* 829 * We want to wait for tx and rx completion to finish 830 * before we tear down the connection, but we have to be 831 * careful not to get stuck waiting on a send ring that 832 * only has unsignaled sends in it. We've shutdown new 833 * sends before getting here so by waiting for signaled 834 * sends to complete we're ensured that there will be no 835 * more tx processing. 836 */ 837 wait_event(rds_ib_ring_empty_wait, 838 rds_ib_ring_empty(&ic->i_recv_ring) && 839 (atomic_read(&ic->i_signaled_sends) == 0) && 840 (atomic_read(&ic->i_fastreg_wrs) == RDS_IB_DEFAULT_FR_WR) && 841 (atomic_read(&ic->i_fastunreg_wrs) == RDS_IB_DEFAULT_FR_INV_WR)); 842 tasklet_kill(&ic->i_send_tasklet); 843 tasklet_kill(&ic->i_recv_tasklet); 844 845 atomic_set(&ic->i_cq_quiesce, 1); 846 847 /* first destroy the ib state that generates callbacks */ 848 if (ic->i_cm_id->qp) 849 rdma_destroy_qp(ic->i_cm_id); 850 if (ic->i_send_cq) { 851 if (ic->rds_ibdev) 852 ibdev_put_vector(ic->rds_ibdev, ic->i_scq_vector); 853 ib_destroy_cq(ic->i_send_cq); 854 } 855 856 if (ic->i_recv_cq) { 857 if (ic->rds_ibdev) 858 ibdev_put_vector(ic->rds_ibdev, ic->i_rcq_vector); 859 ib_destroy_cq(ic->i_recv_cq); 860 } 861 862 /* then free the resources that ib callbacks use */ 863 if (ic->i_send_hdrs) 864 ib_dma_free_coherent(dev, 865 ic->i_send_ring.w_nr * 866 sizeof(struct rds_header), 867 ic->i_send_hdrs, 868 ic->i_send_hdrs_dma); 869 870 if (ic->i_recv_hdrs) 871 ib_dma_free_coherent(dev, 872 ic->i_recv_ring.w_nr * 873 sizeof(struct rds_header), 874 ic->i_recv_hdrs, 875 ic->i_recv_hdrs_dma); 876 877 if (ic->i_ack) 878 ib_dma_free_coherent(dev, sizeof(struct rds_header), 879 ic->i_ack, ic->i_ack_dma); 880 881 if (ic->i_sends) 882 rds_ib_send_clear_ring(ic); 883 if (ic->i_recvs) 884 rds_ib_recv_clear_ring(ic); 885 886 rdma_destroy_id(ic->i_cm_id); 887 888 /* 889 * Move connection back to the nodev list. 890 */ 891 if (ic->rds_ibdev) 892 rds_ib_remove_conn(ic->rds_ibdev, conn); 893 894 ic->i_cm_id = NULL; 895 ic->i_pd = NULL; 896 ic->i_send_cq = NULL; 897 ic->i_recv_cq = NULL; 898 ic->i_send_hdrs = NULL; 899 ic->i_recv_hdrs = NULL; 900 ic->i_ack = NULL; 901 } 902 BUG_ON(ic->rds_ibdev); 903 904 /* Clear pending transmit */ 905 if (ic->i_data_op) { 906 struct rds_message *rm; 907 908 rm = container_of(ic->i_data_op, struct rds_message, data); 909 rds_message_put(rm); 910 ic->i_data_op = NULL; 911 } 912 913 /* Clear the ACK state */ 914 clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags); 915 #ifdef KERNEL_HAS_ATOMIC64 916 atomic64_set(&ic->i_ack_next, 0); 917 #else 918 ic->i_ack_next = 0; 919 #endif 920 ic->i_ack_recv = 0; 921 922 /* Clear flow control state */ 923 ic->i_flowctl = 0; 924 atomic_set(&ic->i_credits, 0); 925 926 rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr); 927 rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr); 928 929 if (ic->i_ibinc) { 930 rds_inc_put(&ic->i_ibinc->ii_inc); 931 ic->i_ibinc = NULL; 932 } 933 934 vfree(ic->i_sends); 935 ic->i_sends = NULL; 936 vfree(ic->i_recvs); 937 ic->i_recvs = NULL; 938 ic->i_active_side = false; 939 } 940 941 int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp) 942 { 943 struct rds_ib_connection *ic; 944 unsigned long flags; 945 int ret; 946 947 /* XXX too lazy? */ 948 ic = kzalloc(sizeof(struct rds_ib_connection), gfp); 949 if (!ic) 950 return -ENOMEM; 951 952 ret = rds_ib_recv_alloc_caches(ic); 953 if (ret) { 954 kfree(ic); 955 return ret; 956 } 957 958 INIT_LIST_HEAD(&ic->ib_node); 959 tasklet_init(&ic->i_send_tasklet, rds_ib_tasklet_fn_send, 960 (unsigned long)ic); 961 tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv, 962 (unsigned long)ic); 963 mutex_init(&ic->i_recv_mutex); 964 #ifndef KERNEL_HAS_ATOMIC64 965 spin_lock_init(&ic->i_ack_lock); 966 #endif 967 atomic_set(&ic->i_signaled_sends, 0); 968 969 /* 970 * rds_ib_conn_shutdown() waits for these to be emptied so they 971 * must be initialized before it can be called. 972 */ 973 rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr); 974 rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr); 975 976 ic->conn = conn; 977 conn->c_transport_data = ic; 978 979 spin_lock_irqsave(&ib_nodev_conns_lock, flags); 980 list_add_tail(&ic->ib_node, &ib_nodev_conns); 981 spin_unlock_irqrestore(&ib_nodev_conns_lock, flags); 982 983 984 rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data); 985 return 0; 986 } 987 988 /* 989 * Free a connection. Connection must be shut down and not set for reconnect. 990 */ 991 void rds_ib_conn_free(void *arg) 992 { 993 struct rds_ib_connection *ic = arg; 994 spinlock_t *lock_ptr; 995 996 rdsdebug("ic %p\n", ic); 997 998 /* 999 * Conn is either on a dev's list or on the nodev list. 1000 * A race with shutdown() or connect() would cause problems 1001 * (since rds_ibdev would change) but that should never happen. 1002 */ 1003 lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock; 1004 1005 spin_lock_irq(lock_ptr); 1006 list_del(&ic->ib_node); 1007 spin_unlock_irq(lock_ptr); 1008 1009 rds_ib_recv_free_caches(ic); 1010 1011 kfree(ic); 1012 } 1013 1014 1015 /* 1016 * An error occurred on the connection 1017 */ 1018 void 1019 __rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...) 1020 { 1021 va_list ap; 1022 1023 rds_conn_drop(conn); 1024 1025 va_start(ap, fmt); 1026 vprintk(fmt, ap); 1027 va_end(ap); 1028 } 1029