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 struct ib_mr *dma_mr; 98 u32 lkey; 99 long timeout; 100 int sq_depth; 101 struct semaphore sq_sem; 102 int rq_depth; 103 struct semaphore rq_sem; 104 atomic_t excess_rc; 105 struct sockaddr_in addr; 106 spinlock_t req_lock; 107 108 struct completion cm_done; 109 }; 110 111 /** 112 * p9_rdma_context - Keeps track of in-process WR 113 * 114 * @wc_op: The original WR op for when the CQE completes in error. 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 enum ib_wc_opcode wc_op; 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 int sq_depth; 140 int rq_depth; 141 long timeout; 142 }; 143 144 /* 145 * Option Parsing (code inspired by NFS code) 146 */ 147 enum { 148 /* Options that take integer arguments */ 149 Opt_port, Opt_rq_depth, Opt_sq_depth, Opt_timeout, Opt_err, 150 }; 151 152 static match_table_t tokens = { 153 {Opt_port, "port=%u"}, 154 {Opt_sq_depth, "sq=%u"}, 155 {Opt_rq_depth, "rq=%u"}, 156 {Opt_timeout, "timeout=%u"}, 157 {Opt_err, NULL}, 158 }; 159 160 /** 161 * parse_opts - parse mount options into rdma options structure 162 * @params: options string passed from mount 163 * @opts: rdma transport-specific structure to parse options into 164 * 165 * Returns 0 upon success, -ERRNO upon failure 166 */ 167 static int parse_opts(char *params, struct p9_rdma_opts *opts) 168 { 169 char *p; 170 substring_t args[MAX_OPT_ARGS]; 171 int option; 172 char *options, *tmp_options; 173 174 opts->port = P9_PORT; 175 opts->sq_depth = P9_RDMA_SQ_DEPTH; 176 opts->rq_depth = P9_RDMA_RQ_DEPTH; 177 opts->timeout = P9_RDMA_TIMEOUT; 178 179 if (!params) 180 return 0; 181 182 tmp_options = kstrdup(params, GFP_KERNEL); 183 if (!tmp_options) { 184 p9_debug(P9_DEBUG_ERROR, 185 "failed to allocate copy of option string\n"); 186 return -ENOMEM; 187 } 188 options = tmp_options; 189 190 while ((p = strsep(&options, ",")) != NULL) { 191 int token; 192 int r; 193 if (!*p) 194 continue; 195 token = match_token(p, tokens, args); 196 if (token == Opt_err) 197 continue; 198 r = match_int(&args[0], &option); 199 if (r < 0) { 200 p9_debug(P9_DEBUG_ERROR, 201 "integer field, but no integer?\n"); 202 continue; 203 } 204 switch (token) { 205 case Opt_port: 206 opts->port = option; 207 break; 208 case Opt_sq_depth: 209 opts->sq_depth = option; 210 break; 211 case Opt_rq_depth: 212 opts->rq_depth = option; 213 break; 214 case Opt_timeout: 215 opts->timeout = option; 216 break; 217 default: 218 continue; 219 } 220 } 221 /* RQ must be at least as large as the SQ */ 222 opts->rq_depth = max(opts->rq_depth, opts->sq_depth); 223 kfree(tmp_options); 224 return 0; 225 } 226 227 static int 228 p9_cm_event_handler(struct rdma_cm_id *id, struct rdma_cm_event *event) 229 { 230 struct p9_client *c = id->context; 231 struct p9_trans_rdma *rdma = c->trans; 232 switch (event->event) { 233 case RDMA_CM_EVENT_ADDR_RESOLVED: 234 BUG_ON(rdma->state != P9_RDMA_INIT); 235 rdma->state = P9_RDMA_ADDR_RESOLVED; 236 break; 237 238 case RDMA_CM_EVENT_ROUTE_RESOLVED: 239 BUG_ON(rdma->state != P9_RDMA_ADDR_RESOLVED); 240 rdma->state = P9_RDMA_ROUTE_RESOLVED; 241 break; 242 243 case RDMA_CM_EVENT_ESTABLISHED: 244 BUG_ON(rdma->state != P9_RDMA_ROUTE_RESOLVED); 245 rdma->state = P9_RDMA_CONNECTED; 246 break; 247 248 case RDMA_CM_EVENT_DISCONNECTED: 249 if (rdma) 250 rdma->state = P9_RDMA_CLOSED; 251 if (c) 252 c->status = Disconnected; 253 break; 254 255 case RDMA_CM_EVENT_TIMEWAIT_EXIT: 256 break; 257 258 case RDMA_CM_EVENT_ADDR_CHANGE: 259 case RDMA_CM_EVENT_ROUTE_ERROR: 260 case RDMA_CM_EVENT_DEVICE_REMOVAL: 261 case RDMA_CM_EVENT_MULTICAST_JOIN: 262 case RDMA_CM_EVENT_MULTICAST_ERROR: 263 case RDMA_CM_EVENT_REJECTED: 264 case RDMA_CM_EVENT_CONNECT_REQUEST: 265 case RDMA_CM_EVENT_CONNECT_RESPONSE: 266 case RDMA_CM_EVENT_CONNECT_ERROR: 267 case RDMA_CM_EVENT_ADDR_ERROR: 268 case RDMA_CM_EVENT_UNREACHABLE: 269 c->status = Disconnected; 270 rdma_disconnect(rdma->cm_id); 271 break; 272 default: 273 BUG(); 274 } 275 complete(&rdma->cm_done); 276 return 0; 277 } 278 279 static void 280 handle_recv(struct p9_client *client, struct p9_trans_rdma *rdma, 281 struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len) 282 { 283 struct p9_req_t *req; 284 int err = 0; 285 int16_t tag; 286 287 req = NULL; 288 ib_dma_unmap_single(rdma->cm_id->device, c->busa, client->msize, 289 DMA_FROM_DEVICE); 290 291 if (status != IB_WC_SUCCESS) 292 goto err_out; 293 294 err = p9_parse_header(c->rc, NULL, NULL, &tag, 1); 295 if (err) 296 goto err_out; 297 298 req = p9_tag_lookup(client, tag); 299 if (!req) 300 goto err_out; 301 302 /* Check that we have not yet received a reply for this request. 303 */ 304 if (unlikely(req->rc)) { 305 pr_err("Duplicate reply for request %d", tag); 306 goto err_out; 307 } 308 309 req->rc = c->rc; 310 p9_client_cb(client, req, REQ_STATUS_RCVD); 311 312 return; 313 314 err_out: 315 p9_debug(P9_DEBUG_ERROR, "req %p err %d status %d\n", req, err, status); 316 rdma->state = P9_RDMA_FLUSHING; 317 client->status = Disconnected; 318 } 319 320 static void 321 handle_send(struct p9_client *client, struct p9_trans_rdma *rdma, 322 struct p9_rdma_context *c, enum ib_wc_status status, u32 byte_len) 323 { 324 ib_dma_unmap_single(rdma->cm_id->device, 325 c->busa, c->req->tc->size, 326 DMA_TO_DEVICE); 327 } 328 329 static void qp_event_handler(struct ib_event *event, void *context) 330 { 331 p9_debug(P9_DEBUG_ERROR, "QP event %d context %p\n", 332 event->event, context); 333 } 334 335 static void cq_comp_handler(struct ib_cq *cq, void *cq_context) 336 { 337 struct p9_client *client = cq_context; 338 struct p9_trans_rdma *rdma = client->trans; 339 int ret; 340 struct ib_wc wc; 341 342 ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP); 343 while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) { 344 struct p9_rdma_context *c = (void *) (unsigned long) wc.wr_id; 345 346 switch (c->wc_op) { 347 case IB_WC_RECV: 348 handle_recv(client, rdma, c, wc.status, wc.byte_len); 349 up(&rdma->rq_sem); 350 break; 351 352 case IB_WC_SEND: 353 handle_send(client, rdma, c, wc.status, wc.byte_len); 354 up(&rdma->sq_sem); 355 break; 356 357 default: 358 pr_err("unexpected completion type, c->wc_op=%d, wc.opcode=%d, status=%d\n", 359 c->wc_op, wc.opcode, wc.status); 360 break; 361 } 362 kfree(c); 363 } 364 } 365 366 static void cq_event_handler(struct ib_event *e, void *v) 367 { 368 p9_debug(P9_DEBUG_ERROR, "CQ event %d context %p\n", e->event, v); 369 } 370 371 static void rdma_destroy_trans(struct p9_trans_rdma *rdma) 372 { 373 if (!rdma) 374 return; 375 376 if (rdma->dma_mr && !IS_ERR(rdma->dma_mr)) 377 ib_dereg_mr(rdma->dma_mr); 378 379 if (rdma->qp && !IS_ERR(rdma->qp)) 380 ib_destroy_qp(rdma->qp); 381 382 if (rdma->pd && !IS_ERR(rdma->pd)) 383 ib_dealloc_pd(rdma->pd); 384 385 if (rdma->cq && !IS_ERR(rdma->cq)) 386 ib_destroy_cq(rdma->cq); 387 388 if (rdma->cm_id && !IS_ERR(rdma->cm_id)) 389 rdma_destroy_id(rdma->cm_id); 390 391 kfree(rdma); 392 } 393 394 static int 395 post_recv(struct p9_client *client, struct p9_rdma_context *c) 396 { 397 struct p9_trans_rdma *rdma = client->trans; 398 struct ib_recv_wr wr, *bad_wr; 399 struct ib_sge sge; 400 401 c->busa = ib_dma_map_single(rdma->cm_id->device, 402 c->rc->sdata, client->msize, 403 DMA_FROM_DEVICE); 404 if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) 405 goto error; 406 407 sge.addr = c->busa; 408 sge.length = client->msize; 409 sge.lkey = rdma->lkey; 410 411 wr.next = NULL; 412 c->wc_op = IB_WC_RECV; 413 wr.wr_id = (unsigned long) c; 414 wr.sg_list = &sge; 415 wr.num_sge = 1; 416 return ib_post_recv(rdma->qp, &wr, &bad_wr); 417 418 error: 419 p9_debug(P9_DEBUG_ERROR, "EIO\n"); 420 return -EIO; 421 } 422 423 static int rdma_request(struct p9_client *client, struct p9_req_t *req) 424 { 425 struct p9_trans_rdma *rdma = client->trans; 426 struct ib_send_wr wr, *bad_wr; 427 struct ib_sge sge; 428 int err = 0; 429 unsigned long flags; 430 struct p9_rdma_context *c = NULL; 431 struct p9_rdma_context *rpl_context = NULL; 432 433 /* When an error occurs between posting the recv and the send, 434 * there will be a receive context posted without a pending request. 435 * Since there is no way to "un-post" it, we remember it and skip 436 * post_recv() for the next request. 437 * So here, 438 * see if we are this `next request' and need to absorb an excess rc. 439 * If yes, then drop and free our own, and do not recv_post(). 440 **/ 441 if (unlikely(atomic_read(&rdma->excess_rc) > 0)) { 442 if ((atomic_sub_return(1, &rdma->excess_rc) >= 0)) { 443 /* Got one ! */ 444 kfree(req->rc); 445 req->rc = NULL; 446 goto dont_need_post_recv; 447 } else { 448 /* We raced and lost. */ 449 atomic_inc(&rdma->excess_rc); 450 } 451 } 452 453 /* Allocate an fcall for the reply */ 454 rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS); 455 if (!rpl_context) { 456 err = -ENOMEM; 457 goto recv_error; 458 } 459 rpl_context->rc = req->rc; 460 461 /* 462 * Post a receive buffer for this request. We need to ensure 463 * there is a reply buffer available for every outstanding 464 * request. A flushed request can result in no reply for an 465 * outstanding request, so we must keep a count to avoid 466 * overflowing the RQ. 467 */ 468 if (down_interruptible(&rdma->rq_sem)) { 469 err = -EINTR; 470 goto recv_error; 471 } 472 473 err = post_recv(client, rpl_context); 474 if (err) { 475 p9_debug(P9_DEBUG_FCALL, "POST RECV failed\n"); 476 goto recv_error; 477 } 478 /* remove posted receive buffer from request structure */ 479 req->rc = NULL; 480 481 dont_need_post_recv: 482 /* Post the request */ 483 c = kmalloc(sizeof *c, GFP_NOFS); 484 if (!c) { 485 err = -ENOMEM; 486 goto send_error; 487 } 488 c->req = req; 489 490 c->busa = ib_dma_map_single(rdma->cm_id->device, 491 c->req->tc->sdata, c->req->tc->size, 492 DMA_TO_DEVICE); 493 if (ib_dma_mapping_error(rdma->cm_id->device, c->busa)) { 494 err = -EIO; 495 goto send_error; 496 } 497 498 sge.addr = c->busa; 499 sge.length = c->req->tc->size; 500 sge.lkey = rdma->lkey; 501 502 wr.next = NULL; 503 c->wc_op = IB_WC_SEND; 504 wr.wr_id = (unsigned long) c; 505 wr.opcode = IB_WR_SEND; 506 wr.send_flags = IB_SEND_SIGNALED; 507 wr.sg_list = &sge; 508 wr.num_sge = 1; 509 510 if (down_interruptible(&rdma->sq_sem)) { 511 err = -EINTR; 512 goto send_error; 513 } 514 515 /* Mark request as `sent' *before* we actually send it, 516 * because doing if after could erase the REQ_STATUS_RCVD 517 * status in case of a very fast reply. 518 */ 519 req->status = REQ_STATUS_SENT; 520 err = ib_post_send(rdma->qp, &wr, &bad_wr); 521 if (err) 522 goto send_error; 523 524 /* Success */ 525 return 0; 526 527 /* Handle errors that happened during or while preparing the send: */ 528 send_error: 529 req->status = REQ_STATUS_ERROR; 530 kfree(c); 531 p9_debug(P9_DEBUG_ERROR, "Error %d in rdma_request()\n", err); 532 533 /* Ach. 534 * We did recv_post(), but not send. We have one recv_post in excess. 535 */ 536 atomic_inc(&rdma->excess_rc); 537 return err; 538 539 /* Handle errors that happened during or while preparing post_recv(): */ 540 recv_error: 541 kfree(rpl_context); 542 spin_lock_irqsave(&rdma->req_lock, flags); 543 if (rdma->state < P9_RDMA_CLOSING) { 544 rdma->state = P9_RDMA_CLOSING; 545 spin_unlock_irqrestore(&rdma->req_lock, flags); 546 rdma_disconnect(rdma->cm_id); 547 } else 548 spin_unlock_irqrestore(&rdma->req_lock, flags); 549 return err; 550 } 551 552 static void rdma_close(struct p9_client *client) 553 { 554 struct p9_trans_rdma *rdma; 555 556 if (!client) 557 return; 558 559 rdma = client->trans; 560 if (!rdma) 561 return; 562 563 client->status = Disconnected; 564 rdma_disconnect(rdma->cm_id); 565 rdma_destroy_trans(rdma); 566 } 567 568 /** 569 * alloc_rdma - Allocate and initialize the rdma transport structure 570 * @opts: Mount options structure 571 */ 572 static struct p9_trans_rdma *alloc_rdma(struct p9_rdma_opts *opts) 573 { 574 struct p9_trans_rdma *rdma; 575 576 rdma = kzalloc(sizeof(struct p9_trans_rdma), GFP_KERNEL); 577 if (!rdma) 578 return NULL; 579 580 rdma->sq_depth = opts->sq_depth; 581 rdma->rq_depth = opts->rq_depth; 582 rdma->timeout = opts->timeout; 583 spin_lock_init(&rdma->req_lock); 584 init_completion(&rdma->cm_done); 585 sema_init(&rdma->sq_sem, rdma->sq_depth); 586 sema_init(&rdma->rq_sem, rdma->rq_depth); 587 atomic_set(&rdma->excess_rc, 0); 588 589 return rdma; 590 } 591 592 static int rdma_cancel(struct p9_client *client, struct p9_req_t *req) 593 { 594 /* Nothing to do here. 595 * We will take care of it (if we have to) in rdma_cancelled() 596 */ 597 return 1; 598 } 599 600 /* A request has been fully flushed without a reply. 601 * That means we have posted one buffer in excess. 602 */ 603 static int rdma_cancelled(struct p9_client *client, struct p9_req_t *req) 604 { 605 struct p9_trans_rdma *rdma = client->trans; 606 atomic_inc(&rdma->excess_rc); 607 return 0; 608 } 609 610 /** 611 * trans_create_rdma - Transport method for creating atransport instance 612 * @client: client instance 613 * @addr: IP address string 614 * @args: Mount options string 615 */ 616 static int 617 rdma_create_trans(struct p9_client *client, const char *addr, char *args) 618 { 619 int err; 620 struct p9_rdma_opts opts; 621 struct p9_trans_rdma *rdma; 622 struct rdma_conn_param conn_param; 623 struct ib_qp_init_attr qp_attr; 624 struct ib_device_attr devattr; 625 626 /* Parse the transport specific mount options */ 627 err = parse_opts(args, &opts); 628 if (err < 0) 629 return err; 630 631 /* Create and initialize the RDMA transport structure */ 632 rdma = alloc_rdma(&opts); 633 if (!rdma) 634 return -ENOMEM; 635 636 /* Create the RDMA CM ID */ 637 rdma->cm_id = rdma_create_id(p9_cm_event_handler, client, RDMA_PS_TCP, 638 IB_QPT_RC); 639 if (IS_ERR(rdma->cm_id)) 640 goto error; 641 642 /* Associate the client with the transport */ 643 client->trans = rdma; 644 645 /* Resolve the server's address */ 646 rdma->addr.sin_family = AF_INET; 647 rdma->addr.sin_addr.s_addr = in_aton(addr); 648 rdma->addr.sin_port = htons(opts.port); 649 err = rdma_resolve_addr(rdma->cm_id, NULL, 650 (struct sockaddr *)&rdma->addr, 651 rdma->timeout); 652 if (err) 653 goto error; 654 err = wait_for_completion_interruptible(&rdma->cm_done); 655 if (err || (rdma->state != P9_RDMA_ADDR_RESOLVED)) 656 goto error; 657 658 /* Resolve the route to the server */ 659 err = rdma_resolve_route(rdma->cm_id, rdma->timeout); 660 if (err) 661 goto error; 662 err = wait_for_completion_interruptible(&rdma->cm_done); 663 if (err || (rdma->state != P9_RDMA_ROUTE_RESOLVED)) 664 goto error; 665 666 /* Query the device attributes */ 667 err = ib_query_device(rdma->cm_id->device, &devattr); 668 if (err) 669 goto error; 670 671 /* Create the Completion Queue */ 672 rdma->cq = ib_create_cq(rdma->cm_id->device, cq_comp_handler, 673 cq_event_handler, client, 674 opts.sq_depth + opts.rq_depth + 1, 0); 675 if (IS_ERR(rdma->cq)) 676 goto error; 677 ib_req_notify_cq(rdma->cq, IB_CQ_NEXT_COMP); 678 679 /* Create the Protection Domain */ 680 rdma->pd = ib_alloc_pd(rdma->cm_id->device); 681 if (IS_ERR(rdma->pd)) 682 goto error; 683 684 /* Cache the DMA lkey in the transport */ 685 rdma->dma_mr = NULL; 686 if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY) 687 rdma->lkey = rdma->cm_id->device->local_dma_lkey; 688 else { 689 rdma->dma_mr = ib_get_dma_mr(rdma->pd, IB_ACCESS_LOCAL_WRITE); 690 if (IS_ERR(rdma->dma_mr)) 691 goto error; 692 rdma->lkey = rdma->dma_mr->lkey; 693 } 694 695 /* Create the Queue Pair */ 696 memset(&qp_attr, 0, sizeof qp_attr); 697 qp_attr.event_handler = qp_event_handler; 698 qp_attr.qp_context = client; 699 qp_attr.cap.max_send_wr = opts.sq_depth; 700 qp_attr.cap.max_recv_wr = opts.rq_depth; 701 qp_attr.cap.max_send_sge = P9_RDMA_SEND_SGE; 702 qp_attr.cap.max_recv_sge = P9_RDMA_RECV_SGE; 703 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; 704 qp_attr.qp_type = IB_QPT_RC; 705 qp_attr.send_cq = rdma->cq; 706 qp_attr.recv_cq = rdma->cq; 707 err = rdma_create_qp(rdma->cm_id, rdma->pd, &qp_attr); 708 if (err) 709 goto error; 710 rdma->qp = rdma->cm_id->qp; 711 712 /* Request a connection */ 713 memset(&conn_param, 0, sizeof(conn_param)); 714 conn_param.private_data = NULL; 715 conn_param.private_data_len = 0; 716 conn_param.responder_resources = P9_RDMA_IRD; 717 conn_param.initiator_depth = P9_RDMA_ORD; 718 err = rdma_connect(rdma->cm_id, &conn_param); 719 if (err) 720 goto error; 721 err = wait_for_completion_interruptible(&rdma->cm_done); 722 if (err || (rdma->state != P9_RDMA_CONNECTED)) 723 goto error; 724 725 client->status = Connected; 726 727 return 0; 728 729 error: 730 rdma_destroy_trans(rdma); 731 return -ENOTCONN; 732 } 733 734 static struct p9_trans_module p9_rdma_trans = { 735 .name = "rdma", 736 .maxsize = P9_RDMA_MAXSIZE, 737 .def = 0, 738 .owner = THIS_MODULE, 739 .create = rdma_create_trans, 740 .close = rdma_close, 741 .request = rdma_request, 742 .cancel = rdma_cancel, 743 .cancelled = rdma_cancelled, 744 }; 745 746 /** 747 * p9_trans_rdma_init - Register the 9P RDMA transport driver 748 */ 749 static int __init p9_trans_rdma_init(void) 750 { 751 v9fs_register_trans(&p9_rdma_trans); 752 return 0; 753 } 754 755 static void __exit p9_trans_rdma_exit(void) 756 { 757 v9fs_unregister_trans(&p9_rdma_trans); 758 } 759 760 module_init(p9_trans_rdma_init); 761 module_exit(p9_trans_rdma_exit); 762 763 MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>"); 764 MODULE_DESCRIPTION("RDMA Transport for 9P"); 765 MODULE_LICENSE("Dual BSD/GPL"); 766