1 /* 2 * linux/fs/9p/trans_rdma.c 3 * 4 * RDMA transport layer based on the trans_fd.c implementation. 5 * 6 * Copyright (C) 2008 by Tom Tucker <tom@opengridcomputing.com> 7 * Copyright (C) 2006 by Russ Cox <rsc@swtch.com> 8 * Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net> 9 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com> 10 * Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com> 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License version 2 14 * as published by the Free Software Foundation. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to: 23 * Free Software Foundation 24 * 51 Franklin Street, Fifth Floor 25 * Boston, MA 02111-1301 USA 26 * 27 */ 28 29 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 30 31 #include <linux/in.h> 32 #include <linux/module.h> 33 #include <linux/net.h> 34 #include <linux/ipv6.h> 35 #include <linux/kthread.h> 36 #include <linux/errno.h> 37 #include <linux/kernel.h> 38 #include <linux/un.h> 39 #include <linux/uaccess.h> 40 #include <linux/inet.h> 41 #include <linux/idr.h> 42 #include <linux/file.h> 43 #include <linux/parser.h> 44 #include <linux/semaphore.h> 45 #include <linux/slab.h> 46 #include <linux/seq_file.h> 47 #include <net/9p/9p.h> 48 #include <net/9p/client.h> 49 #include <net/9p/transport.h> 50 #include <rdma/ib_verbs.h> 51 #include <rdma/rdma_cm.h> 52 53 #define P9_PORT 5640 54 #define P9_RDMA_SQ_DEPTH 32 55 #define P9_RDMA_RQ_DEPTH 32 56 #define P9_RDMA_SEND_SGE 4 57 #define P9_RDMA_RECV_SGE 4 58 #define P9_RDMA_IRD 0 59 #define P9_RDMA_ORD 0 60 #define P9_RDMA_TIMEOUT 30000 /* 30 seconds */ 61 #define P9_RDMA_MAXSIZE (1024*1024) /* 1MB */ 62 63 /** 64 * struct p9_trans_rdma - RDMA transport instance 65 * 66 * @state: tracks the transport state machine for connection setup and tear down 67 * @cm_id: The RDMA CM ID 68 * @pd: Protection Domain pointer 69 * @qp: Queue Pair pointer 70 * @cq: Completion Queue pointer 71 * @timeout: Number of uSecs to wait for connection management events 72 * @privport: Whether a privileged port may be used 73 * @port: The port to use 74 * @sq_depth: The depth of the Send Queue 75 * @sq_sem: Semaphore for the SQ 76 * @rq_depth: The depth of the Receive Queue. 77 * @rq_sem: Semaphore for the RQ 78 * @excess_rc : Amount of posted Receive Contexts without a pending request. 79 * See rdma_request() 80 * @addr: The remote peer's address 81 * @req_lock: Protects the active request list 82 * @cm_done: Completion event for connection management tracking 83 */ 84 struct p9_trans_rdma { 85 enum { 86 P9_RDMA_INIT, 87 P9_RDMA_ADDR_RESOLVED, 88 P9_RDMA_ROUTE_RESOLVED, 89 P9_RDMA_CONNECTED, 90 P9_RDMA_FLUSHING, 91 P9_RDMA_CLOSING, 92 P9_RDMA_CLOSED, 93 } state; 94 struct rdma_cm_id *cm_id; 95 struct ib_pd *pd; 96 struct ib_qp *qp; 97 struct ib_cq *cq; 98 long timeout; 99 bool privport; 100 u16 port; 101 int sq_depth; 102 struct semaphore sq_sem; 103 int rq_depth; 104 struct semaphore rq_sem; 105 atomic_t excess_rc; 106 struct sockaddr_in addr; 107 spinlock_t req_lock; 108 109 struct completion cm_done; 110 }; 111 112 /** 113 * p9_rdma_context - Keeps track of in-process WR 114 * 115 * @busa: Bus address to unmap when the WR completes 116 * @req: Keeps track of requests (send) 117 * @rc: Keepts track of replies (receive) 118 */ 119 struct p9_rdma_req; 120 struct p9_rdma_context { 121 struct ib_cqe cqe; 122 dma_addr_t busa; 123 union { 124 struct p9_req_t *req; 125 struct p9_fcall *rc; 126 }; 127 }; 128 129 /** 130 * p9_rdma_opts - Collection of mount options 131 * @port: port of connection 132 * @sq_depth: The requested depth of the SQ. This really doesn't need 133 * to be any deeper than the number of threads used in the client 134 * @rq_depth: The depth of the RQ. Should be greater than or equal to SQ depth 135 * @timeout: Time to wait in msecs for CM events 136 */ 137 struct p9_rdma_opts { 138 short port; 139 bool privport; 140 int sq_depth; 141 int rq_depth; 142 long timeout; 143 }; 144 145 /* 146 * Option Parsing (code inspired by NFS code) 147 */ 148 enum { 149 /* Options that take integer arguments */ 150 Opt_port, Opt_rq_depth, Opt_sq_depth, Opt_timeout, 151 /* Options that take no argument */ 152 Opt_privport, 153 Opt_err, 154 }; 155 156 static match_table_t tokens = { 157 {Opt_port, "port=%u"}, 158 {Opt_sq_depth, "sq=%u"}, 159 {Opt_rq_depth, "rq=%u"}, 160 {Opt_timeout, "timeout=%u"}, 161 {Opt_privport, "privport"}, 162 {Opt_err, NULL}, 163 }; 164 165 static int p9_rdma_show_options(struct seq_file *m, struct p9_client *clnt) 166 { 167 struct p9_trans_rdma *rdma = clnt->trans; 168 169 if (rdma->port != P9_PORT) 170 seq_printf(m, ",port=%u", rdma->port); 171 if (rdma->sq_depth != P9_RDMA_SQ_DEPTH) 172 seq_printf(m, ",sq=%u", rdma->sq_depth); 173 if (rdma->rq_depth != P9_RDMA_RQ_DEPTH) 174 seq_printf(m, ",rq=%u", rdma->rq_depth); 175 if (rdma->timeout != P9_RDMA_TIMEOUT) 176 seq_printf(m, ",timeout=%lu", rdma->timeout); 177 if (rdma->privport) 178 seq_puts(m, ",privport"); 179 return 0; 180 } 181 182 /** 183 * parse_opts - parse mount options into rdma options structure 184 * @params: options string passed from mount 185 * @opts: rdma transport-specific structure to parse options into 186 * 187 * Returns 0 upon success, -ERRNO upon failure 188 */ 189 static int parse_opts(char *params, struct p9_rdma_opts *opts) 190 { 191 char *p; 192 substring_t args[MAX_OPT_ARGS]; 193 int option; 194 char *options, *tmp_options; 195 196 opts->port = P9_PORT; 197 opts->sq_depth = P9_RDMA_SQ_DEPTH; 198 opts->rq_depth = P9_RDMA_RQ_DEPTH; 199 opts->timeout = P9_RDMA_TIMEOUT; 200 opts->privport = false; 201 202 if (!params) 203 return 0; 204 205 tmp_options = kstrdup(params, GFP_KERNEL); 206 if (!tmp_options) { 207 p9_debug(P9_DEBUG_ERROR, 208 "failed to allocate copy of option string\n"); 209 return -ENOMEM; 210 } 211 options = tmp_options; 212 213 while ((p = strsep(&options, ",")) != NULL) { 214 int token; 215 int r; 216 if (!*p) 217 continue; 218 token = match_token(p, tokens, args); 219 if ((token != Opt_err) && (token != Opt_privport)) { 220 r = match_int(&args[0], &option); 221 if (r < 0) { 222 p9_debug(P9_DEBUG_ERROR, 223 "integer field, but no integer?\n"); 224 continue; 225 } 226 } 227 switch (token) { 228 case Opt_port: 229 opts->port = option; 230 break; 231 case Opt_sq_depth: 232 opts->sq_depth = option; 233 break; 234 case Opt_rq_depth: 235 opts->rq_depth = option; 236 break; 237 case Opt_timeout: 238 opts->timeout = option; 239 break; 240 case Opt_privport: 241 opts->privport = true; 242 break; 243 default: 244 continue; 245 } 246 } 247 /* RQ must be at least as large as the SQ */ 248 opts->rq_depth = max(opts->rq_depth, opts->sq_depth); 249 kfree(tmp_options); 250 return 0; 251 } 252 253 static int 254 p9_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event) 255 { 256 struct p9_client *c = id->context; 257 struct p9_trans_rdma *rdma = c->trans; 258 switch (event->event) { 259 case RDMA_CM_EVENT_ADDR_RESOLVED: 260 BUG_ON(rdma->state != P9_RDMA_INIT); 261 rdma->state = P9_RDMA_ADDR_RESOLVED; 262 break; 263 264 case RDMA_CM_EVENT_ROUTE_RESOLVED: 265 BUG_ON(rdma->state != P9_RDMA_ADDR_RESOLVED); 266 rdma->state = P9_RDMA_ROUTE_RESOLVED; 267 break; 268 269 case RDMA_CM_EVENT_ESTABLISHED: 270 BUG_ON(rdma->state != P9_RDMA_ROUTE_RESOLVED); 271 rdma->state = P9_RDMA_CONNECTED; 272 break; 273 274 case RDMA_CM_EVENT_DISCONNECTED: 275 if (rdma) 276 rdma->state = P9_RDMA_CLOSED; 277 if (c) 278 c->status = Disconnected; 279 break; 280 281 case RDMA_CM_EVENT_TIMEWAIT_EXIT: 282 break; 283 284 case RDMA_CM_EVENT_ADDR_CHANGE: 285 case RDMA_CM_EVENT_ROUTE_ERROR: 286 case RDMA_CM_EVENT_DEVICE_REMOVAL: 287 case RDMA_CM_EVENT_MULTICAST_JOIN: 288 case RDMA_CM_EVENT_MULTICAST_ERROR: 289 case RDMA_CM_EVENT_REJECTED: 290 case RDMA_CM_EVENT_CONNECT_REQUEST: 291 case RDMA_CM_EVENT_CONNECT_RESPONSE: 292 case RDMA_CM_EVENT_CONNECT_ERROR: 293 case RDMA_CM_EVENT_ADDR_ERROR: 294 case RDMA_CM_EVENT_UNREACHABLE: 295 c->status = Disconnected; 296 rdma_disconnect(rdma->cm_id); 297 break; 298 default: 299 BUG(); 300 } 301 complete(&rdma->cm_done); 302 return 0; 303 } 304 305 static void 306 recv_done(struct ib_cq *cq, struct ib_wc *wc) 307 { 308 struct p9_client *client = cq->cq_context; 309 struct p9_trans_rdma *rdma = client->trans; 310 struct p9_rdma_context *c = 311 container_of(wc->wr_cqe, struct p9_rdma_context, cqe); 312 struct p9_req_t *req; 313 int err = 0; 314 int16_t tag; 315 316 req = NULL; 317 ib_dma_unmap_single(rdma->cm_id->device, c->busa, client->msize, 318 DMA_FROM_DEVICE); 319 320 if (wc->status != IB_WC_SUCCESS) 321 goto err_out; 322 323 err = p9_parse_header(c->rc, NULL, NULL, &tag, 1); 324 if (err) 325 goto err_out; 326 327 req = p9_tag_lookup(client, tag); 328 if (!req) 329 goto err_out; 330 331 /* Check that we have not yet received a reply for this request. 332 */ 333 if (unlikely(req->rc)) { 334 pr_err("Duplicate reply for request %d", tag); 335 goto err_out; 336 } 337 338 req->rc = c->rc; 339 p9_client_cb(client, req, REQ_STATUS_RCVD); 340 341 out: 342 up(&rdma->rq_sem); 343 kfree(c); 344 return; 345 346 err_out: 347 p9_debug(P9_DEBUG_ERROR, "req %p err %d status %d\n", 348 req, err, wc->status); 349 rdma->state = P9_RDMA_FLUSHING; 350 client->status = Disconnected; 351 goto out; 352 } 353 354 static void 355 send_done(struct ib_cq *cq, struct ib_wc *wc) 356 { 357 struct p9_client *client = cq->cq_context; 358 struct p9_trans_rdma *rdma = client->trans; 359 struct p9_rdma_context *c = 360 container_of(wc->wr_cqe, struct p9_rdma_context, cqe); 361 362 ib_dma_unmap_single(rdma->cm_id->device, 363 c->busa, c->req->tc->size, 364 DMA_TO_DEVICE); 365 up(&rdma->sq_sem); 366 kfree(c); 367 } 368 369 static void qp_event_handler(struct ib_event *event, void *context) 370 { 371 p9_debug(P9_DEBUG_ERROR, "QP event %d context %p\n", 372 event->event, context); 373 } 374 375 static void rdma_destroy_trans(struct p9_trans_rdma *rdma) 376 { 377 if (!rdma) 378 return; 379 380 if (rdma->qp && !IS_ERR(rdma->qp)) 381 ib_destroy_qp(rdma->qp); 382 383 if (rdma->pd && !IS_ERR(rdma->pd)) 384 ib_dealloc_pd(rdma->pd); 385 386 if (rdma->cq && !IS_ERR(rdma->cq)) 387 ib_free_cq(rdma->cq); 388 389 if (rdma->cm_id && !IS_ERR(rdma->cm_id)) 390 rdma_destroy_id(rdma->cm_id); 391 392 kfree(rdma); 393 } 394 395 static int 396 post_recv(struct p9_client *client, struct p9_rdma_context *c) 397 { 398 struct p9_trans_rdma *rdma = client->trans; 399 struct ib_recv_wr wr, *bad_wr; 400 struct ib_sge sge; 401 402 c->busa = ib_dma_map_single(rdma->cm_id->device, 403 c->rc->sdata, client->msize, 404 DMA_FROM_DEVICE); 405 if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) 406 goto error; 407 408 c->cqe.done = recv_done; 409 410 sge.addr = c->busa; 411 sge.length = client->msize; 412 sge.lkey = rdma->pd->local_dma_lkey; 413 414 wr.next = NULL; 415 wr.wr_cqe = &c->cqe; 416 wr.sg_list = &sge; 417 wr.num_sge = 1; 418 return ib_post_recv(rdma->qp, &wr, &bad_wr); 419 420 error: 421 p9_debug(P9_DEBUG_ERROR, "EIO\n"); 422 return -EIO; 423 } 424 425 static int rdma_request(struct p9_client *client, struct p9_req_t *req) 426 { 427 struct p9_trans_rdma *rdma = client->trans; 428 struct ib_send_wr wr, *bad_wr; 429 struct ib_sge sge; 430 int err = 0; 431 unsigned long flags; 432 struct p9_rdma_context *c = NULL; 433 struct p9_rdma_context *rpl_context = NULL; 434 435 /* When an error occurs between posting the recv and the send, 436 * there will be a receive context posted without a pending request. 437 * Since there is no way to "un-post" it, we remember it and skip 438 * post_recv() for the next request. 439 * So here, 440 * see if we are this `next request' and need to absorb an excess rc. 441 * If yes, then drop and free our own, and do not recv_post(). 442 **/ 443 if (unlikely(atomic_read(&rdma->excess_rc) > 0)) { 444 if ((atomic_sub_return(1, &rdma->excess_rc) >= 0)) { 445 /* Got one ! */ 446 kfree(req->rc); 447 req->rc = NULL; 448 goto dont_need_post_recv; 449 } else { 450 /* We raced and lost. */ 451 atomic_inc(&rdma->excess_rc); 452 } 453 } 454 455 /* Allocate an fcall for the reply */ 456 rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS); 457 if (!rpl_context) { 458 err = -ENOMEM; 459 goto recv_error; 460 } 461 rpl_context->rc = req->rc; 462 463 /* 464 * Post a receive buffer for this request. We need to ensure 465 * there is a reply buffer available for every outstanding 466 * request. A flushed request can result in no reply for an 467 * outstanding request, so we must keep a count to avoid 468 * overflowing the RQ. 469 */ 470 if (down_interruptible(&rdma->rq_sem)) { 471 err = -EINTR; 472 goto recv_error; 473 } 474 475 err = post_recv(client, rpl_context); 476 if (err) { 477 p9_debug(P9_DEBUG_FCALL, "POST RECV failed\n"); 478 goto recv_error; 479 } 480 /* remove posted receive buffer from request structure */ 481 req->rc = NULL; 482 483 dont_need_post_recv: 484 /* Post the request */ 485 c = kmalloc(sizeof *c, GFP_NOFS); 486 if (!c) { 487 err = -ENOMEM; 488 goto send_error; 489 } 490 c->req = req; 491 492 c->busa = ib_dma_map_single(rdma->cm_id->device, 493 c->req->tc->sdata, c->req->tc->size, 494 DMA_TO_DEVICE); 495 if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) { 496 err = -EIO; 497 goto send_error; 498 } 499 500 c->cqe.done = send_done; 501 502 sge.addr = c->busa; 503 sge.length = c->req->tc->size; 504 sge.lkey = rdma->pd->local_dma_lkey; 505 506 wr.next = NULL; 507 wr.wr_cqe = &c->cqe; 508 wr.opcode = IB_WR_SEND; 509 wr.send_flags = IB_SEND_SIGNALED; 510 wr.sg_list = &sge; 511 wr.num_sge = 1; 512 513 if (down_interruptible(&rdma->sq_sem)) { 514 err = -EINTR; 515 goto send_error; 516 } 517 518 /* Mark request as `sent' *before* we actually send it, 519 * because doing if after could erase the REQ_STATUS_RCVD 520 * status in case of a very fast reply. 521 */ 522 req->status = REQ_STATUS_SENT; 523 err = ib_post_send(rdma->qp, &wr, &bad_wr); 524 if (err) 525 goto send_error; 526 527 /* Success */ 528 return 0; 529 530 /* Handle errors that happened during or while preparing the send: */ 531 send_error: 532 req->status = REQ_STATUS_ERROR; 533 kfree(c); 534 p9_debug(P9_DEBUG_ERROR, "Error %d in rdma_request()\n", err); 535 536 /* Ach. 537 * We did recv_post(), but not send. We have one recv_post in excess. 538 */ 539 atomic_inc(&rdma->excess_rc); 540 return err; 541 542 /* Handle errors that happened during or while preparing post_recv(): */ 543 recv_error: 544 kfree(rpl_context); 545 spin_lock_irqsave(&rdma->req_lock, flags); 546 if (rdma->state < P9_RDMA_CLOSING) { 547 rdma->state = P9_RDMA_CLOSING; 548 spin_unlock_irqrestore(&rdma->req_lock, flags); 549 rdma_disconnect(rdma->cm_id); 550 } else 551 spin_unlock_irqrestore(&rdma->req_lock, flags); 552 return err; 553 } 554 555 static void rdma_close(struct p9_client *client) 556 { 557 struct p9_trans_rdma *rdma; 558 559 if (!client) 560 return; 561 562 rdma = client->trans; 563 if (!rdma) 564 return; 565 566 client->status = Disconnected; 567 rdma_disconnect(rdma->cm_id); 568 rdma_destroy_trans(rdma); 569 } 570 571 /** 572 * alloc_rdma - Allocate and initialize the rdma transport structure 573 * @opts: Mount options structure 574 */ 575 static struct p9_trans_rdma *alloc_rdma(struct p9_rdma_opts *opts) 576 { 577 struct p9_trans_rdma *rdma; 578 579 rdma = kzalloc(sizeof(struct p9_trans_rdma), GFP_KERNEL); 580 if (!rdma) 581 return NULL; 582 583 rdma->port = opts->port; 584 rdma->privport = opts->privport; 585 rdma->sq_depth = opts->sq_depth; 586 rdma->rq_depth = opts->rq_depth; 587 rdma->timeout = opts->timeout; 588 spin_lock_init(&rdma->req_lock); 589 init_completion(&rdma->cm_done); 590 sema_init(&rdma->sq_sem, rdma->sq_depth); 591 sema_init(&rdma->rq_sem, rdma->rq_depth); 592 atomic_set(&rdma->excess_rc, 0); 593 594 return rdma; 595 } 596 597 static int rdma_cancel(struct p9_client *client, struct p9_req_t *req) 598 { 599 /* Nothing to do here. 600 * We will take care of it (if we have to) in rdma_cancelled() 601 */ 602 return 1; 603 } 604 605 /* A request has been fully flushed without a reply. 606 * That means we have posted one buffer in excess. 607 */ 608 static int rdma_cancelled(struct p9_client *client, struct p9_req_t *req) 609 { 610 struct p9_trans_rdma *rdma = client->trans; 611 atomic_inc(&rdma->excess_rc); 612 return 0; 613 } 614 615 static int p9_rdma_bind_privport(struct p9_trans_rdma *rdma) 616 { 617 struct sockaddr_in cl = { 618 .sin_family = AF_INET, 619 .sin_addr.s_addr = htonl(INADDR_ANY), 620 }; 621 int port, err = -EINVAL; 622 623 for (port = P9_DEF_MAX_RESVPORT; port >= P9_DEF_MIN_RESVPORT; port--) { 624 cl.sin_port = htons((ushort)port); 625 err = rdma_bind_addr(rdma->cm_id, (struct sockaddr *)&cl); 626 if (err != -EADDRINUSE) 627 break; 628 } 629 return err; 630 } 631 632 /** 633 * rdma_create_trans - Transport method for creating a transport instance 634 * @client: client instance 635 * @addr: IP address string 636 * @args: Mount options string 637 */ 638 static int 639 rdma_create_trans(struct p9_client *client, const char *addr, char *args) 640 { 641 int err; 642 struct p9_rdma_opts opts; 643 struct p9_trans_rdma *rdma; 644 struct rdma_conn_param conn_param; 645 struct ib_qp_init_attr qp_attr; 646 647 /* Parse the transport specific mount options */ 648 err = parse_opts(args, &opts); 649 if (err < 0) 650 return err; 651 652 /* Create and initialize the RDMA transport structure */ 653 rdma = alloc_rdma(&opts); 654 if (!rdma) 655 return -ENOMEM; 656 657 /* Create the RDMA CM ID */ 658 rdma->cm_id = rdma_create_id(&init_net, p9_cm_event_handler, client, 659 RDMA_PS_TCP, IB_QPT_RC); 660 if (IS_ERR(rdma->cm_id)) 661 goto error; 662 663 /* Associate the client with the transport */ 664 client->trans = rdma; 665 666 /* Bind to a privileged port if we need to */ 667 if (opts.privport) { 668 err = p9_rdma_bind_privport(rdma); 669 if (err < 0) { 670 pr_err("%s (%d): problem binding to privport: %d\n", 671 __func__, task_pid_nr(current), -err); 672 goto error; 673 } 674 } 675 676 /* Resolve the server's address */ 677 rdma->addr.sin_family = AF_INET; 678 rdma->addr.sin_addr.s_addr = in_aton(addr); 679 rdma->addr.sin_port = htons(opts.port); 680 err = rdma_resolve_addr(rdma->cm_id, NULL, 681 (struct sockaddr *)&rdma->addr, 682 rdma->timeout); 683 if (err) 684 goto error; 685 err = wait_for_completion_interruptible(&rdma->cm_done); 686 if (err || (rdma->state != P9_RDMA_ADDR_RESOLVED)) 687 goto error; 688 689 /* Resolve the route to the server */ 690 err = rdma_resolve_route(rdma->cm_id, rdma->timeout); 691 if (err) 692 goto error; 693 err = wait_for_completion_interruptible(&rdma->cm_done); 694 if (err || (rdma->state != P9_RDMA_ROUTE_RESOLVED)) 695 goto error; 696 697 /* Create the Completion Queue */ 698 rdma->cq = ib_alloc_cq(rdma->cm_id->device, client, 699 opts.sq_depth + opts.rq_depth + 1, 700 0, IB_POLL_SOFTIRQ); 701 if (IS_ERR(rdma->cq)) 702 goto error; 703 704 /* Create the Protection Domain */ 705 rdma->pd = ib_alloc_pd(rdma->cm_id->device, 0); 706 if (IS_ERR(rdma->pd)) 707 goto error; 708 709 /* Create the Queue Pair */ 710 memset(&qp_attr, 0, sizeof qp_attr); 711 qp_attr.event_handler = qp_event_handler; 712 qp_attr.qp_context = client; 713 qp_attr.cap.max_send_wr = opts.sq_depth; 714 qp_attr.cap.max_recv_wr = opts.rq_depth; 715 qp_attr.cap.max_send_sge = P9_RDMA_SEND_SGE; 716 qp_attr.cap.max_recv_sge = P9_RDMA_RECV_SGE; 717 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; 718 qp_attr.qp_type = IB_QPT_RC; 719 qp_attr.send_cq = rdma->cq; 720 qp_attr.recv_cq = rdma->cq; 721 err = rdma_create_qp(rdma->cm_id, rdma->pd, &qp_attr); 722 if (err) 723 goto error; 724 rdma->qp = rdma->cm_id->qp; 725 726 /* Request a connection */ 727 memset(&conn_param, 0, sizeof(conn_param)); 728 conn_param.private_data = NULL; 729 conn_param.private_data_len = 0; 730 conn_param.responder_resources = P9_RDMA_IRD; 731 conn_param.initiator_depth = P9_RDMA_ORD; 732 err = rdma_connect(rdma->cm_id, &conn_param); 733 if (err) 734 goto error; 735 err = wait_for_completion_interruptible(&rdma->cm_done); 736 if (err || (rdma->state != P9_RDMA_CONNECTED)) 737 goto error; 738 739 client->status = Connected; 740 741 return 0; 742 743 error: 744 rdma_destroy_trans(rdma); 745 return -ENOTCONN; 746 } 747 748 static struct p9_trans_module p9_rdma_trans = { 749 .name = "rdma", 750 .maxsize = P9_RDMA_MAXSIZE, 751 .def = 0, 752 .owner = THIS_MODULE, 753 .create = rdma_create_trans, 754 .close = rdma_close, 755 .request = rdma_request, 756 .cancel = rdma_cancel, 757 .cancelled = rdma_cancelled, 758 .show_options = p9_rdma_show_options, 759 }; 760 761 /** 762 * p9_trans_rdma_init - Register the 9P RDMA transport driver 763 */ 764 static int __init p9_trans_rdma_init(void) 765 { 766 v9fs_register_trans(&p9_rdma_trans); 767 return 0; 768 } 769 770 static void __exit p9_trans_rdma_exit(void) 771 { 772 v9fs_unregister_trans(&p9_rdma_trans); 773 } 774 775 module_init(p9_trans_rdma_init); 776 module_exit(p9_trans_rdma_exit); 777 778 MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>"); 779 MODULE_DESCRIPTION("RDMA Transport for 9P"); 780 MODULE_LICENSE("Dual BSD/GPL"); 781