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 <net/9p/9p.h> 47 #include <net/9p/client.h> 48 #include <net/9p/transport.h> 49 #include <rdma/ib_verbs.h> 50 #include <rdma/rdma_cm.h> 51 52 #define P9_PORT 5640 53 #define P9_RDMA_SQ_DEPTH 32 54 #define P9_RDMA_RQ_DEPTH 32 55 #define P9_RDMA_SEND_SGE 4 56 #define P9_RDMA_RECV_SGE 4 57 #define P9_RDMA_IRD 0 58 #define P9_RDMA_ORD 0 59 #define P9_RDMA_TIMEOUT 30000 /* 30 seconds */ 60 #define P9_RDMA_MAXSIZE (1024*1024) /* 1MB */ 61 62 /** 63 * struct p9_trans_rdma - RDMA transport instance 64 * 65 * @state: tracks the transport state machine for connection setup and tear down 66 * @cm_id: The RDMA CM ID 67 * @pd: Protection Domain pointer 68 * @qp: Queue Pair pointer 69 * @cq: Completion Queue pointer 70 * @dm_mr: DMA Memory Region pointer 71 * @lkey: The local access only memory region key 72 * @timeout: Number of uSecs to wait for connection management events 73 * @sq_depth: The depth of the Send Queue 74 * @sq_sem: Semaphore for the SQ 75 * @rq_depth: The depth of the Receive Queue. 76 * @rq_sem: Semaphore for the RQ 77 * @excess_rc : Amount of posted Receive Contexts without a pending request. 78 * See rdma_request() 79 * @addr: The remote peer's address 80 * @req_lock: Protects the active request list 81 * @cm_done: Completion event for connection management tracking 82 */ 83 struct p9_trans_rdma { 84 enum { 85 P9_RDMA_INIT, 86 P9_RDMA_ADDR_RESOLVED, 87 P9_RDMA_ROUTE_RESOLVED, 88 P9_RDMA_CONNECTED, 89 P9_RDMA_FLUSHING, 90 P9_RDMA_CLOSING, 91 P9_RDMA_CLOSED, 92 } state; 93 struct rdma_cm_id *cm_id; 94 struct ib_pd *pd; 95 struct ib_qp *qp; 96 struct ib_cq *cq; 97 long timeout; 98 int sq_depth; 99 struct semaphore sq_sem; 100 int rq_depth; 101 struct semaphore rq_sem; 102 atomic_t excess_rc; 103 struct sockaddr_in addr; 104 spinlock_t req_lock; 105 106 struct completion cm_done; 107 }; 108 109 /** 110 * p9_rdma_context - Keeps track of in-process WR 111 * 112 * @wc_op: The original WR op for when the CQE completes in error. 113 * @busa: Bus address to unmap when the WR completes 114 * @req: Keeps track of requests (send) 115 * @rc: Keepts track of replies (receive) 116 */ 117 struct p9_rdma_req; 118 struct p9_rdma_context { 119 enum ib_wc_opcode wc_op; 120 dma_addr_t busa; 121 union { 122 struct p9_req_t *req; 123 struct p9_fcall *rc; 124 }; 125 }; 126 127 /** 128 * p9_rdma_opts - Collection of mount options 129 * @port: port of connection 130 * @sq_depth: The requested depth of the SQ. This really doesn't need 131 * to be any deeper than the number of threads used in the client 132 * @rq_depth: The depth of the RQ. Should be greater than or equal to SQ depth 133 * @timeout: Time to wait in msecs for CM events 134 */ 135 struct p9_rdma_opts { 136 short port; 137 int sq_depth; 138 int rq_depth; 139 long timeout; 140 int privport; 141 }; 142 143 /* 144 * Option Parsing (code inspired by NFS code) 145 */ 146 enum { 147 /* Options that take integer arguments */ 148 Opt_port, Opt_rq_depth, Opt_sq_depth, Opt_timeout, 149 /* Options that take no argument */ 150 Opt_privport, 151 Opt_err, 152 }; 153 154 static match_table_t tokens = { 155 {Opt_port, "port=%u"}, 156 {Opt_sq_depth, "sq=%u"}, 157 {Opt_rq_depth, "rq=%u"}, 158 {Opt_timeout, "timeout=%u"}, 159 {Opt_privport, "privport"}, 160 {Opt_err, NULL}, 161 }; 162 163 /** 164 * parse_opts - parse mount options into rdma options structure 165 * @params: options string passed from mount 166 * @opts: rdma transport-specific structure to parse options into 167 * 168 * Returns 0 upon success, -ERRNO upon failure 169 */ 170 static int parse_opts(char *params, struct p9_rdma_opts *opts) 171 { 172 char *p; 173 substring_t args[MAX_OPT_ARGS]; 174 int option; 175 char *options, *tmp_options; 176 177 opts->port = P9_PORT; 178 opts->sq_depth = P9_RDMA_SQ_DEPTH; 179 opts->rq_depth = P9_RDMA_RQ_DEPTH; 180 opts->timeout = P9_RDMA_TIMEOUT; 181 opts->privport = 0; 182 183 if (!params) 184 return 0; 185 186 tmp_options = kstrdup(params, GFP_KERNEL); 187 if (!tmp_options) { 188 p9_debug(P9_DEBUG_ERROR, 189 "failed to allocate copy of option string\n"); 190 return -ENOMEM; 191 } 192 options = tmp_options; 193 194 while ((p = strsep(&options, ",")) != NULL) { 195 int token; 196 int r; 197 if (!*p) 198 continue; 199 token = match_token(p, tokens, args); 200 if ((token != Opt_err) && (token != Opt_privport)) { 201 r = match_int(&args[0], &option); 202 if (r < 0) { 203 p9_debug(P9_DEBUG_ERROR, 204 "integer field, but no integer?\n"); 205 continue; 206 } 207 } 208 switch (token) { 209 case Opt_port: 210 opts->port = option; 211 break; 212 case Opt_sq_depth: 213 opts->sq_depth = option; 214 break; 215 case Opt_rq_depth: 216 opts->rq_depth = option; 217 break; 218 case Opt_timeout: 219 opts->timeout = option; 220 break; 221 case Opt_privport: 222 opts->privport = 1; 223 break; 224 default: 225 continue; 226 } 227 } 228 /* RQ must be at least as large as the SQ */ 229 opts->rq_depth = max(opts->rq_depth, opts->sq_depth); 230 kfree(tmp_options); 231 return 0; 232 } 233 234 static int 235 p9_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event) 236 { 237 struct p9_client *c = id->context; 238 struct p9_trans_rdma *rdma = c->trans; 239 switch (event->event) { 240 case RDMA_CM_EVENT_ADDR_RESOLVED: 241 BUG_ON(rdma->state != P9_RDMA_INIT); 242 rdma->state = P9_RDMA_ADDR_RESOLVED; 243 break; 244 245 case RDMA_CM_EVENT_ROUTE_RESOLVED: 246 BUG_ON(rdma->state != P9_RDMA_ADDR_RESOLVED); 247 rdma->state = P9_RDMA_ROUTE_RESOLVED; 248 break; 249 250 case RDMA_CM_EVENT_ESTABLISHED: 251 BUG_ON(rdma->state != P9_RDMA_ROUTE_RESOLVED); 252 rdma->state = P9_RDMA_CONNECTED; 253 break; 254 255 case RDMA_CM_EVENT_DISCONNECTED: 256 if (rdma) 257 rdma->state = P9_RDMA_CLOSED; 258 if (c) 259 c->status = Disconnected; 260 break; 261 262 case RDMA_CM_EVENT_TIMEWAIT_EXIT: 263 break; 264 265 case RDMA_CM_EVENT_ADDR_CHANGE: 266 case RDMA_CM_EVENT_ROUTE_ERROR: 267 case RDMA_CM_EVENT_DEVICE_REMOVAL: 268 case RDMA_CM_EVENT_MULTICAST_JOIN: 269 case RDMA_CM_EVENT_MULTICAST_ERROR: 270 case RDMA_CM_EVENT_REJECTED: 271 case RDMA_CM_EVENT_CONNECT_REQUEST: 272 case RDMA_CM_EVENT_CONNECT_RESPONSE: 273 case RDMA_CM_EVENT_CONNECT_ERROR: 274 case RDMA_CM_EVENT_ADDR_ERROR: 275 case RDMA_CM_EVENT_UNREACHABLE: 276 c->status = Disconnected; 277 rdma_disconnect(rdma->cm_id); 278 break; 279 default: 280 BUG(); 281 } 282 complete(&rdma->cm_done); 283 return 0; 284 } 285 286 static void 287 handle_recv(struct p9_client *client, struct p9_trans_rdma *rdma, 288 struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len) 289 { 290 struct p9_req_t *req; 291 int err = 0; 292 int16_t tag; 293 294 req = NULL; 295 ib_dma_unmap_single(rdma->cm_id->device, c->busa, client->msize, 296 DMA_FROM_DEVICE); 297 298 if (status != IB_WC_SUCCESS) 299 goto err_out; 300 301 err = p9_parse_header(c->rc, NULL, NULL, &tag, 1); 302 if (err) 303 goto err_out; 304 305 req = p9_tag_lookup(client, tag); 306 if (!req) 307 goto err_out; 308 309 /* Check that we have not yet received a reply for this request. 310 */ 311 if (unlikely(req->rc)) { 312 pr_err("Duplicate reply for request %d", tag); 313 goto err_out; 314 } 315 316 req->rc = c->rc; 317 p9_client_cb(client, req, REQ_STATUS_RCVD); 318 319 return; 320 321 err_out: 322 p9_debug(P9_DEBUG_ERROR, "req %p err %d status %d\n", req, err, status); 323 rdma->state = P9_RDMA_FLUSHING; 324 client->status = Disconnected; 325 } 326 327 static void 328 handle_send(struct p9_client *client, struct p9_trans_rdma *rdma, 329 struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len) 330 { 331 ib_dma_unmap_single(rdma->cm_id->device, 332 c->busa, c->req->tc->size, 333 DMA_TO_DEVICE); 334 } 335 336 static void qp_event_handler(struct ib_event *event, void *context) 337 { 338 p9_debug(P9_DEBUG_ERROR, "QP event %d context %p\n", 339 event->event, context); 340 } 341 342 static void cq_comp_handler(struct ib_cq *cq, void *cq_context) 343 { 344 struct p9_client *client = cq_context; 345 struct p9_trans_rdma *rdma = client->trans; 346 int ret; 347 struct ib_wc wc; 348 349 ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP); 350 while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) { 351 struct p9_rdma_context *c = (void *) (unsigned long) wc.wr_id; 352 353 switch (c->wc_op) { 354 case IB_WC_RECV: 355 handle_recv(client, rdma, c, wc.status, wc.byte_len); 356 up(&rdma->rq_sem); 357 break; 358 359 case IB_WC_SEND: 360 handle_send(client, rdma, c, wc.status, wc.byte_len); 361 up(&rdma->sq_sem); 362 break; 363 364 default: 365 pr_err("unexpected completion type, c->wc_op=%d, wc.opcode=%d, status=%d\n", 366 c->wc_op, wc.opcode, wc.status); 367 break; 368 } 369 kfree(c); 370 } 371 } 372 373 static void cq_event_handler(struct ib_event *e, void *v) 374 { 375 p9_debug(P9_DEBUG_ERROR, "CQ event %d context %p\n", e->event, v); 376 } 377 378 static void rdma_destroy_trans(struct p9_trans_rdma *rdma) 379 { 380 if (!rdma) 381 return; 382 383 if (rdma->qp && !IS_ERR(rdma->qp)) 384 ib_destroy_qp(rdma->qp); 385 386 if (rdma->pd && !IS_ERR(rdma->pd)) 387 ib_dealloc_pd(rdma->pd); 388 389 if (rdma->cq && !IS_ERR(rdma->cq)) 390 ib_destroy_cq(rdma->cq); 391 392 if (rdma->cm_id && !IS_ERR(rdma->cm_id)) 393 rdma_destroy_id(rdma->cm_id); 394 395 kfree(rdma); 396 } 397 398 static int 399 post_recv(struct p9_client *client, struct p9_rdma_context *c) 400 { 401 struct p9_trans_rdma *rdma = client->trans; 402 struct ib_recv_wr wr, *bad_wr; 403 struct ib_sge sge; 404 405 c->busa = ib_dma_map_single(rdma->cm_id->device, 406 c->rc->sdata, client->msize, 407 DMA_FROM_DEVICE); 408 if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) 409 goto error; 410 411 sge.addr = c->busa; 412 sge.length = client->msize; 413 sge.lkey = rdma->pd->local_dma_lkey; 414 415 wr.next = NULL; 416 c->wc_op = IB_WC_RECV; 417 wr.wr_id = (unsigned long) c; 418 wr.sg_list = &sge; 419 wr.num_sge = 1; 420 return ib_post_recv(rdma->qp, &wr, &bad_wr); 421 422 error: 423 p9_debug(P9_DEBUG_ERROR, "EIO\n"); 424 return -EIO; 425 } 426 427 static int rdma_request(struct p9_client *client, struct p9_req_t *req) 428 { 429 struct p9_trans_rdma *rdma = client->trans; 430 struct ib_send_wr wr, *bad_wr; 431 struct ib_sge sge; 432 int err = 0; 433 unsigned long flags; 434 struct p9_rdma_context *c = NULL; 435 struct p9_rdma_context *rpl_context = NULL; 436 437 /* When an error occurs between posting the recv and the send, 438 * there will be a receive context posted without a pending request. 439 * Since there is no way to "un-post" it, we remember it and skip 440 * post_recv() for the next request. 441 * So here, 442 * see if we are this `next request' and need to absorb an excess rc. 443 * If yes, then drop and free our own, and do not recv_post(). 444 **/ 445 if (unlikely(atomic_read(&rdma->excess_rc) > 0)) { 446 if ((atomic_sub_return(1, &rdma->excess_rc) >= 0)) { 447 /* Got one ! */ 448 kfree(req->rc); 449 req->rc = NULL; 450 goto dont_need_post_recv; 451 } else { 452 /* We raced and lost. */ 453 atomic_inc(&rdma->excess_rc); 454 } 455 } 456 457 /* Allocate an fcall for the reply */ 458 rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS); 459 if (!rpl_context) { 460 err = -ENOMEM; 461 goto recv_error; 462 } 463 rpl_context->rc = req->rc; 464 465 /* 466 * Post a receive buffer for this request. We need to ensure 467 * there is a reply buffer available for every outstanding 468 * request. A flushed request can result in no reply for an 469 * outstanding request, so we must keep a count to avoid 470 * overflowing the RQ. 471 */ 472 if (down_interruptible(&rdma->rq_sem)) { 473 err = -EINTR; 474 goto recv_error; 475 } 476 477 err = post_recv(client, rpl_context); 478 if (err) { 479 p9_debug(P9_DEBUG_FCALL, "POST RECV failed\n"); 480 goto recv_error; 481 } 482 /* remove posted receive buffer from request structure */ 483 req->rc = NULL; 484 485 dont_need_post_recv: 486 /* Post the request */ 487 c = kmalloc(sizeof *c, GFP_NOFS); 488 if (!c) { 489 err = -ENOMEM; 490 goto send_error; 491 } 492 c->req = req; 493 494 c->busa = ib_dma_map_single(rdma->cm_id->device, 495 c->req->tc->sdata, c->req->tc->size, 496 DMA_TO_DEVICE); 497 if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) { 498 err = -EIO; 499 goto send_error; 500 } 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 c->wc_op = IB_WC_SEND; 508 wr.wr_id = (unsigned long) c; 509 wr.opcode = IB_WR_SEND; 510 wr.send_flags = IB_SEND_SIGNALED; 511 wr.sg_list = &sge; 512 wr.num_sge = 1; 513 514 if (down_interruptible(&rdma->sq_sem)) { 515 err = -EINTR; 516 goto send_error; 517 } 518 519 /* Mark request as `sent' *before* we actually send it, 520 * because doing if after could erase the REQ_STATUS_RCVD 521 * status in case of a very fast reply. 522 */ 523 req->status = REQ_STATUS_SENT; 524 err = ib_post_send(rdma->qp, &wr, &bad_wr); 525 if (err) 526 goto send_error; 527 528 /* Success */ 529 return 0; 530 531 /* Handle errors that happened during or while preparing the send: */ 532 send_error: 533 req->status = REQ_STATUS_ERROR; 534 kfree(c); 535 p9_debug(P9_DEBUG_ERROR, "Error %d in rdma_request()\n", err); 536 537 /* Ach. 538 * We did recv_post(), but not send. We have one recv_post in excess. 539 */ 540 atomic_inc(&rdma->excess_rc); 541 return err; 542 543 /* Handle errors that happened during or while preparing post_recv(): */ 544 recv_error: 545 kfree(rpl_context); 546 spin_lock_irqsave(&rdma->req_lock, flags); 547 if (rdma->state < P9_RDMA_CLOSING) { 548 rdma->state = P9_RDMA_CLOSING; 549 spin_unlock_irqrestore(&rdma->req_lock, flags); 550 rdma_disconnect(rdma->cm_id); 551 } else 552 spin_unlock_irqrestore(&rdma->req_lock, flags); 553 return err; 554 } 555 556 static void rdma_close(struct p9_client *client) 557 { 558 struct p9_trans_rdma *rdma; 559 560 if (!client) 561 return; 562 563 rdma = client->trans; 564 if (!rdma) 565 return; 566 567 client->status = Disconnected; 568 rdma_disconnect(rdma->cm_id); 569 rdma_destroy_trans(rdma); 570 } 571 572 /** 573 * alloc_rdma - Allocate and initialize the rdma transport structure 574 * @opts: Mount options structure 575 */ 576 static struct p9_trans_rdma *alloc_rdma(struct p9_rdma_opts *opts) 577 { 578 struct p9_trans_rdma *rdma; 579 580 rdma = kzalloc(sizeof(struct p9_trans_rdma), GFP_KERNEL); 581 if (!rdma) 582 return NULL; 583 584 rdma->sq_depth = opts->sq_depth; 585 rdma->rq_depth = opts->rq_depth; 586 rdma->timeout = opts->timeout; 587 spin_lock_init(&rdma->req_lock); 588 init_completion(&rdma->cm_done); 589 sema_init(&rdma->sq_sem, rdma->sq_depth); 590 sema_init(&rdma->rq_sem, rdma->rq_depth); 591 atomic_set(&rdma->excess_rc, 0); 592 593 return rdma; 594 } 595 596 static int rdma_cancel(struct p9_client *client, struct p9_req_t *req) 597 { 598 /* Nothing to do here. 599 * We will take care of it (if we have to) in rdma_cancelled() 600 */ 601 return 1; 602 } 603 604 /* A request has been fully flushed without a reply. 605 * That means we have posted one buffer in excess. 606 */ 607 static int rdma_cancelled(struct p9_client *client, struct p9_req_t *req) 608 { 609 struct p9_trans_rdma *rdma = client->trans; 610 atomic_inc(&rdma->excess_rc); 611 return 0; 612 } 613 614 static int p9_rdma_bind_privport(struct p9_trans_rdma *rdma) 615 { 616 struct sockaddr_in cl = { 617 .sin_family = AF_INET, 618 .sin_addr.s_addr = htonl(INADDR_ANY), 619 }; 620 int port, err = -EINVAL; 621 622 for (port = P9_DEF_MAX_RESVPORT; port >= P9_DEF_MIN_RESVPORT; port--) { 623 cl.sin_port = htons((ushort)port); 624 err = rdma_bind_addr(rdma->cm_id, (struct sockaddr *)&cl); 625 if (err != -EADDRINUSE) 626 break; 627 } 628 return err; 629 } 630 631 /** 632 * trans_create_rdma - Transport method for creating atransport instance 633 * @client: client instance 634 * @addr: IP address string 635 * @args: Mount options string 636 */ 637 static int 638 rdma_create_trans(struct p9_client *client, const char *addr, char *args) 639 { 640 int err; 641 struct p9_rdma_opts opts; 642 struct p9_trans_rdma *rdma; 643 struct rdma_conn_param conn_param; 644 struct ib_qp_init_attr qp_attr; 645 struct ib_cq_init_attr cq_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(p9_cm_event_handler, client, RDMA_PS_TCP, 659 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 cq_attr.cqe = opts.sq_depth + opts.rq_depth + 1; 699 rdma->cq = ib_create_cq(rdma->cm_id->device, cq_comp_handler, 700 cq_event_handler, client, 701 &cq_attr); 702 if (IS_ERR(rdma->cq)) 703 goto error; 704 ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP); 705 706 /* Create the Protection Domain */ 707 rdma->pd = ib_alloc_pd(rdma->cm_id->device); 708 if (IS_ERR(rdma->pd)) 709 goto error; 710 711 /* Create the Queue Pair */ 712 memset(&qp_attr, 0, sizeof qp_attr); 713 qp_attr.event_handler = qp_event_handler; 714 qp_attr.qp_context = client; 715 qp_attr.cap.max_send_wr = opts.sq_depth; 716 qp_attr.cap.max_recv_wr = opts.rq_depth; 717 qp_attr.cap.max_send_sge = P9_RDMA_SEND_SGE; 718 qp_attr.cap.max_recv_sge = P9_RDMA_RECV_SGE; 719 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; 720 qp_attr.qp_type = IB_QPT_RC; 721 qp_attr.send_cq = rdma->cq; 722 qp_attr.recv_cq = rdma->cq; 723 err = rdma_create_qp(rdma->cm_id, rdma->pd, &qp_attr); 724 if (err) 725 goto error; 726 rdma->qp = rdma->cm_id->qp; 727 728 /* Request a connection */ 729 memset(&conn_param, 0, sizeof(conn_param)); 730 conn_param.private_data = NULL; 731 conn_param.private_data_len = 0; 732 conn_param.responder_resources = P9_RDMA_IRD; 733 conn_param.initiator_depth = P9_RDMA_ORD; 734 err = rdma_connect(rdma->cm_id, &conn_param); 735 if (err) 736 goto error; 737 err = wait_for_completion_interruptible(&rdma->cm_done); 738 if (err || (rdma->state != P9_RDMA_CONNECTED)) 739 goto error; 740 741 client->status = Connected; 742 743 return 0; 744 745 error: 746 rdma_destroy_trans(rdma); 747 return -ENOTCONN; 748 } 749 750 static struct p9_trans_module p9_rdma_trans = { 751 .name = "rdma", 752 .maxsize = P9_RDMA_MAXSIZE, 753 .def = 0, 754 .owner = THIS_MODULE, 755 .create = rdma_create_trans, 756 .close = rdma_close, 757 .request = rdma_request, 758 .cancel = rdma_cancel, 759 .cancelled = rdma_cancelled, 760 }; 761 762 /** 763 * p9_trans_rdma_init - Register the 9P RDMA transport driver 764 */ 765 static int __init p9_trans_rdma_init(void) 766 { 767 v9fs_register_trans(&p9_rdma_trans); 768 return 0; 769 } 770 771 static void __exit p9_trans_rdma_exit(void) 772 { 773 v9fs_unregister_trans(&p9_rdma_trans); 774 } 775 776 module_init(p9_trans_rdma_init); 777 module_exit(p9_trans_rdma_exit); 778 779 MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>"); 780 MODULE_DESCRIPTION("RDMA Transport for 9P"); 781 MODULE_LICENSE("Dual BSD/GPL"); 782