1 /* 2 * Copyright (c) 2005-2007 Network Appliance, Inc. 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 BSD-type 8 * license below: 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 17 * Redistributions in binary form must reproduce the above 18 * copyright notice, this list of conditions and the following 19 * disclaimer in the documentation and/or other materials provided 20 * with the distribution. 21 * 22 * Neither the name of the Network Appliance, Inc. nor the names of 23 * its contributors may be used to endorse or promote products 24 * derived from this software without specific prior written 25 * permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 38 * 39 * Author: Tom Tucker <tom@opengridcomputing.com> 40 */ 41 42 #include <linux/sunrpc/svc_xprt.h> 43 #include <linux/sunrpc/debug.h> 44 #include <linux/sunrpc/rpc_rdma.h> 45 #include <linux/sched.h> 46 #include <linux/slab.h> 47 #include <linux/spinlock.h> 48 #include <linux/workqueue.h> 49 #include <rdma/ib_verbs.h> 50 #include <rdma/rdma_cm.h> 51 #include <linux/sunrpc/svc_rdma.h> 52 53 #define RPCDBG_FACILITY RPCDBG_SVCXPRT 54 55 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, 56 struct net *net, 57 struct sockaddr *sa, int salen, 58 int flags); 59 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt); 60 static void svc_rdma_release_rqst(struct svc_rqst *); 61 static void dto_tasklet_func(unsigned long data); 62 static void svc_rdma_detach(struct svc_xprt *xprt); 63 static void svc_rdma_free(struct svc_xprt *xprt); 64 static int svc_rdma_has_wspace(struct svc_xprt *xprt); 65 static void rq_cq_reap(struct svcxprt_rdma *xprt); 66 static void sq_cq_reap(struct svcxprt_rdma *xprt); 67 68 static DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL); 69 static DEFINE_SPINLOCK(dto_lock); 70 static LIST_HEAD(dto_xprt_q); 71 72 static struct svc_xprt_ops svc_rdma_ops = { 73 .xpo_create = svc_rdma_create, 74 .xpo_recvfrom = svc_rdma_recvfrom, 75 .xpo_sendto = svc_rdma_sendto, 76 .xpo_release_rqst = svc_rdma_release_rqst, 77 .xpo_detach = svc_rdma_detach, 78 .xpo_free = svc_rdma_free, 79 .xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr, 80 .xpo_has_wspace = svc_rdma_has_wspace, 81 .xpo_accept = svc_rdma_accept, 82 }; 83 84 struct svc_xprt_class svc_rdma_class = { 85 .xcl_name = "rdma", 86 .xcl_owner = THIS_MODULE, 87 .xcl_ops = &svc_rdma_ops, 88 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP, 89 }; 90 91 /* WR context cache. Created in svc_rdma.c */ 92 extern struct kmem_cache *svc_rdma_ctxt_cachep; 93 94 /* Workqueue created in svc_rdma.c */ 95 extern struct workqueue_struct *svc_rdma_wq; 96 97 struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt) 98 { 99 struct svc_rdma_op_ctxt *ctxt; 100 101 while (1) { 102 ctxt = kmem_cache_alloc(svc_rdma_ctxt_cachep, GFP_KERNEL); 103 if (ctxt) 104 break; 105 schedule_timeout_uninterruptible(msecs_to_jiffies(500)); 106 } 107 ctxt->xprt = xprt; 108 INIT_LIST_HEAD(&ctxt->dto_q); 109 ctxt->count = 0; 110 ctxt->frmr = NULL; 111 atomic_inc(&xprt->sc_ctxt_used); 112 return ctxt; 113 } 114 115 void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt) 116 { 117 struct svcxprt_rdma *xprt = ctxt->xprt; 118 int i; 119 for (i = 0; i < ctxt->count && ctxt->sge[i].length; i++) { 120 /* 121 * Unmap the DMA addr in the SGE if the lkey matches 122 * the sc_dma_lkey, otherwise, ignore it since it is 123 * an FRMR lkey and will be unmapped later when the 124 * last WR that uses it completes. 125 */ 126 if (ctxt->sge[i].lkey == xprt->sc_dma_lkey) { 127 atomic_dec(&xprt->sc_dma_used); 128 ib_dma_unmap_page(xprt->sc_cm_id->device, 129 ctxt->sge[i].addr, 130 ctxt->sge[i].length, 131 ctxt->direction); 132 } 133 } 134 } 135 136 void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages) 137 { 138 struct svcxprt_rdma *xprt; 139 int i; 140 141 BUG_ON(!ctxt); 142 xprt = ctxt->xprt; 143 if (free_pages) 144 for (i = 0; i < ctxt->count; i++) 145 put_page(ctxt->pages[i]); 146 147 kmem_cache_free(svc_rdma_ctxt_cachep, ctxt); 148 atomic_dec(&xprt->sc_ctxt_used); 149 } 150 151 /* Temporary NFS request map cache. Created in svc_rdma.c */ 152 extern struct kmem_cache *svc_rdma_map_cachep; 153 154 /* 155 * Temporary NFS req mappings are shared across all transport 156 * instances. These are short lived and should be bounded by the number 157 * of concurrent server threads * depth of the SQ. 158 */ 159 struct svc_rdma_req_map *svc_rdma_get_req_map(void) 160 { 161 struct svc_rdma_req_map *map; 162 while (1) { 163 map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL); 164 if (map) 165 break; 166 schedule_timeout_uninterruptible(msecs_to_jiffies(500)); 167 } 168 map->count = 0; 169 map->frmr = NULL; 170 return map; 171 } 172 173 void svc_rdma_put_req_map(struct svc_rdma_req_map *map) 174 { 175 kmem_cache_free(svc_rdma_map_cachep, map); 176 } 177 178 /* ib_cq event handler */ 179 static void cq_event_handler(struct ib_event *event, void *context) 180 { 181 struct svc_xprt *xprt = context; 182 dprintk("svcrdma: received CQ event id=%d, context=%p\n", 183 event->event, context); 184 set_bit(XPT_CLOSE, &xprt->xpt_flags); 185 } 186 187 /* QP event handler */ 188 static void qp_event_handler(struct ib_event *event, void *context) 189 { 190 struct svc_xprt *xprt = context; 191 192 switch (event->event) { 193 /* These are considered benign events */ 194 case IB_EVENT_PATH_MIG: 195 case IB_EVENT_COMM_EST: 196 case IB_EVENT_SQ_DRAINED: 197 case IB_EVENT_QP_LAST_WQE_REACHED: 198 dprintk("svcrdma: QP event %d received for QP=%p\n", 199 event->event, event->element.qp); 200 break; 201 /* These are considered fatal events */ 202 case IB_EVENT_PATH_MIG_ERR: 203 case IB_EVENT_QP_FATAL: 204 case IB_EVENT_QP_REQ_ERR: 205 case IB_EVENT_QP_ACCESS_ERR: 206 case IB_EVENT_DEVICE_FATAL: 207 default: 208 dprintk("svcrdma: QP ERROR event %d received for QP=%p, " 209 "closing transport\n", 210 event->event, event->element.qp); 211 set_bit(XPT_CLOSE, &xprt->xpt_flags); 212 break; 213 } 214 } 215 216 /* 217 * Data Transfer Operation Tasklet 218 * 219 * Walks a list of transports with I/O pending, removing entries as 220 * they are added to the server's I/O pending list. Two bits indicate 221 * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave 222 * spinlock that serializes access to the transport list with the RQ 223 * and SQ interrupt handlers. 224 */ 225 static void dto_tasklet_func(unsigned long data) 226 { 227 struct svcxprt_rdma *xprt; 228 unsigned long flags; 229 230 spin_lock_irqsave(&dto_lock, flags); 231 while (!list_empty(&dto_xprt_q)) { 232 xprt = list_entry(dto_xprt_q.next, 233 struct svcxprt_rdma, sc_dto_q); 234 list_del_init(&xprt->sc_dto_q); 235 spin_unlock_irqrestore(&dto_lock, flags); 236 237 rq_cq_reap(xprt); 238 sq_cq_reap(xprt); 239 240 svc_xprt_put(&xprt->sc_xprt); 241 spin_lock_irqsave(&dto_lock, flags); 242 } 243 spin_unlock_irqrestore(&dto_lock, flags); 244 } 245 246 /* 247 * Receive Queue Completion Handler 248 * 249 * Since an RQ completion handler is called on interrupt context, we 250 * need to defer the handling of the I/O to a tasklet 251 */ 252 static void rq_comp_handler(struct ib_cq *cq, void *cq_context) 253 { 254 struct svcxprt_rdma *xprt = cq_context; 255 unsigned long flags; 256 257 /* Guard against unconditional flush call for destroyed QP */ 258 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0) 259 return; 260 261 /* 262 * Set the bit regardless of whether or not it's on the list 263 * because it may be on the list already due to an SQ 264 * completion. 265 */ 266 set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags); 267 268 /* 269 * If this transport is not already on the DTO transport queue, 270 * add it 271 */ 272 spin_lock_irqsave(&dto_lock, flags); 273 if (list_empty(&xprt->sc_dto_q)) { 274 svc_xprt_get(&xprt->sc_xprt); 275 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q); 276 } 277 spin_unlock_irqrestore(&dto_lock, flags); 278 279 /* Tasklet does all the work to avoid irqsave locks. */ 280 tasklet_schedule(&dto_tasklet); 281 } 282 283 /* 284 * rq_cq_reap - Process the RQ CQ. 285 * 286 * Take all completing WC off the CQE and enqueue the associated DTO 287 * context on the dto_q for the transport. 288 * 289 * Note that caller must hold a transport reference. 290 */ 291 static void rq_cq_reap(struct svcxprt_rdma *xprt) 292 { 293 int ret; 294 struct ib_wc wc; 295 struct svc_rdma_op_ctxt *ctxt = NULL; 296 297 if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags)) 298 return; 299 300 ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP); 301 atomic_inc(&rdma_stat_rq_poll); 302 303 while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) { 304 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id; 305 ctxt->wc_status = wc.status; 306 ctxt->byte_len = wc.byte_len; 307 svc_rdma_unmap_dma(ctxt); 308 if (wc.status != IB_WC_SUCCESS) { 309 /* Close the transport */ 310 dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt); 311 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 312 svc_rdma_put_context(ctxt, 1); 313 svc_xprt_put(&xprt->sc_xprt); 314 continue; 315 } 316 spin_lock_bh(&xprt->sc_rq_dto_lock); 317 list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q); 318 spin_unlock_bh(&xprt->sc_rq_dto_lock); 319 svc_xprt_put(&xprt->sc_xprt); 320 } 321 322 if (ctxt) 323 atomic_inc(&rdma_stat_rq_prod); 324 325 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags); 326 /* 327 * If data arrived before established event, 328 * don't enqueue. This defers RPC I/O until the 329 * RDMA connection is complete. 330 */ 331 if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags)) 332 svc_xprt_enqueue(&xprt->sc_xprt); 333 } 334 335 /* 336 * Process a completion context 337 */ 338 static void process_context(struct svcxprt_rdma *xprt, 339 struct svc_rdma_op_ctxt *ctxt) 340 { 341 svc_rdma_unmap_dma(ctxt); 342 343 switch (ctxt->wr_op) { 344 case IB_WR_SEND: 345 if (test_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags)) 346 svc_rdma_put_frmr(xprt, ctxt->frmr); 347 svc_rdma_put_context(ctxt, 1); 348 break; 349 350 case IB_WR_RDMA_WRITE: 351 svc_rdma_put_context(ctxt, 0); 352 break; 353 354 case IB_WR_RDMA_READ: 355 case IB_WR_RDMA_READ_WITH_INV: 356 if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) { 357 struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr; 358 BUG_ON(!read_hdr); 359 if (test_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags)) 360 svc_rdma_put_frmr(xprt, ctxt->frmr); 361 spin_lock_bh(&xprt->sc_rq_dto_lock); 362 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags); 363 list_add_tail(&read_hdr->dto_q, 364 &xprt->sc_read_complete_q); 365 spin_unlock_bh(&xprt->sc_rq_dto_lock); 366 svc_xprt_enqueue(&xprt->sc_xprt); 367 } 368 svc_rdma_put_context(ctxt, 0); 369 break; 370 371 default: 372 printk(KERN_ERR "svcrdma: unexpected completion type, " 373 "opcode=%d\n", 374 ctxt->wr_op); 375 break; 376 } 377 } 378 379 /* 380 * Send Queue Completion Handler - potentially called on interrupt context. 381 * 382 * Note that caller must hold a transport reference. 383 */ 384 static void sq_cq_reap(struct svcxprt_rdma *xprt) 385 { 386 struct svc_rdma_op_ctxt *ctxt = NULL; 387 struct ib_wc wc; 388 struct ib_cq *cq = xprt->sc_sq_cq; 389 int ret; 390 391 if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags)) 392 return; 393 394 ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP); 395 atomic_inc(&rdma_stat_sq_poll); 396 while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) { 397 if (wc.status != IB_WC_SUCCESS) 398 /* Close the transport */ 399 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 400 401 /* Decrement used SQ WR count */ 402 atomic_dec(&xprt->sc_sq_count); 403 wake_up(&xprt->sc_send_wait); 404 405 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id; 406 if (ctxt) 407 process_context(xprt, ctxt); 408 409 svc_xprt_put(&xprt->sc_xprt); 410 } 411 412 if (ctxt) 413 atomic_inc(&rdma_stat_sq_prod); 414 } 415 416 static void sq_comp_handler(struct ib_cq *cq, void *cq_context) 417 { 418 struct svcxprt_rdma *xprt = cq_context; 419 unsigned long flags; 420 421 /* Guard against unconditional flush call for destroyed QP */ 422 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0) 423 return; 424 425 /* 426 * Set the bit regardless of whether or not it's on the list 427 * because it may be on the list already due to an RQ 428 * completion. 429 */ 430 set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags); 431 432 /* 433 * If this transport is not already on the DTO transport queue, 434 * add it 435 */ 436 spin_lock_irqsave(&dto_lock, flags); 437 if (list_empty(&xprt->sc_dto_q)) { 438 svc_xprt_get(&xprt->sc_xprt); 439 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q); 440 } 441 spin_unlock_irqrestore(&dto_lock, flags); 442 443 /* Tasklet does all the work to avoid irqsave locks. */ 444 tasklet_schedule(&dto_tasklet); 445 } 446 447 static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv, 448 int listener) 449 { 450 struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL); 451 452 if (!cma_xprt) 453 return NULL; 454 svc_xprt_init(&svc_rdma_class, &cma_xprt->sc_xprt, serv); 455 INIT_LIST_HEAD(&cma_xprt->sc_accept_q); 456 INIT_LIST_HEAD(&cma_xprt->sc_dto_q); 457 INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q); 458 INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q); 459 INIT_LIST_HEAD(&cma_xprt->sc_frmr_q); 460 init_waitqueue_head(&cma_xprt->sc_send_wait); 461 462 spin_lock_init(&cma_xprt->sc_lock); 463 spin_lock_init(&cma_xprt->sc_rq_dto_lock); 464 spin_lock_init(&cma_xprt->sc_frmr_q_lock); 465 466 cma_xprt->sc_ord = svcrdma_ord; 467 468 cma_xprt->sc_max_req_size = svcrdma_max_req_size; 469 cma_xprt->sc_max_requests = svcrdma_max_requests; 470 cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT; 471 atomic_set(&cma_xprt->sc_sq_count, 0); 472 atomic_set(&cma_xprt->sc_ctxt_used, 0); 473 474 if (listener) 475 set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags); 476 477 return cma_xprt; 478 } 479 480 struct page *svc_rdma_get_page(void) 481 { 482 struct page *page; 483 484 while ((page = alloc_page(GFP_KERNEL)) == NULL) { 485 /* If we can't get memory, wait a bit and try again */ 486 printk(KERN_INFO "svcrdma: out of memory...retrying in 1000 " 487 "jiffies.\n"); 488 schedule_timeout_uninterruptible(msecs_to_jiffies(1000)); 489 } 490 return page; 491 } 492 493 int svc_rdma_post_recv(struct svcxprt_rdma *xprt) 494 { 495 struct ib_recv_wr recv_wr, *bad_recv_wr; 496 struct svc_rdma_op_ctxt *ctxt; 497 struct page *page; 498 dma_addr_t pa; 499 int sge_no; 500 int buflen; 501 int ret; 502 503 ctxt = svc_rdma_get_context(xprt); 504 buflen = 0; 505 ctxt->direction = DMA_FROM_DEVICE; 506 for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) { 507 BUG_ON(sge_no >= xprt->sc_max_sge); 508 page = svc_rdma_get_page(); 509 ctxt->pages[sge_no] = page; 510 pa = ib_dma_map_page(xprt->sc_cm_id->device, 511 page, 0, PAGE_SIZE, 512 DMA_FROM_DEVICE); 513 if (ib_dma_mapping_error(xprt->sc_cm_id->device, pa)) 514 goto err_put_ctxt; 515 atomic_inc(&xprt->sc_dma_used); 516 ctxt->sge[sge_no].addr = pa; 517 ctxt->sge[sge_no].length = PAGE_SIZE; 518 ctxt->sge[sge_no].lkey = xprt->sc_dma_lkey; 519 ctxt->count = sge_no + 1; 520 buflen += PAGE_SIZE; 521 } 522 recv_wr.next = NULL; 523 recv_wr.sg_list = &ctxt->sge[0]; 524 recv_wr.num_sge = ctxt->count; 525 recv_wr.wr_id = (u64)(unsigned long)ctxt; 526 527 svc_xprt_get(&xprt->sc_xprt); 528 ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr); 529 if (ret) { 530 svc_rdma_unmap_dma(ctxt); 531 svc_rdma_put_context(ctxt, 1); 532 svc_xprt_put(&xprt->sc_xprt); 533 } 534 return ret; 535 536 err_put_ctxt: 537 svc_rdma_unmap_dma(ctxt); 538 svc_rdma_put_context(ctxt, 1); 539 return -ENOMEM; 540 } 541 542 /* 543 * This function handles the CONNECT_REQUEST event on a listening 544 * endpoint. It is passed the cma_id for the _new_ connection. The context in 545 * this cma_id is inherited from the listening cma_id and is the svc_xprt 546 * structure for the listening endpoint. 547 * 548 * This function creates a new xprt for the new connection and enqueues it on 549 * the accept queue for the listent xprt. When the listen thread is kicked, it 550 * will call the recvfrom method on the listen xprt which will accept the new 551 * connection. 552 */ 553 static void handle_connect_req(struct rdma_cm_id *new_cma_id, size_t client_ird) 554 { 555 struct svcxprt_rdma *listen_xprt = new_cma_id->context; 556 struct svcxprt_rdma *newxprt; 557 struct sockaddr *sa; 558 559 /* Create a new transport */ 560 newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0); 561 if (!newxprt) { 562 dprintk("svcrdma: failed to create new transport\n"); 563 return; 564 } 565 newxprt->sc_cm_id = new_cma_id; 566 new_cma_id->context = newxprt; 567 dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n", 568 newxprt, newxprt->sc_cm_id, listen_xprt); 569 570 /* Save client advertised inbound read limit for use later in accept. */ 571 newxprt->sc_ord = client_ird; 572 573 /* Set the local and remote addresses in the transport */ 574 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr; 575 svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa)); 576 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr; 577 svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa)); 578 579 /* 580 * Enqueue the new transport on the accept queue of the listening 581 * transport 582 */ 583 spin_lock_bh(&listen_xprt->sc_lock); 584 list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q); 585 spin_unlock_bh(&listen_xprt->sc_lock); 586 587 /* 588 * Can't use svc_xprt_received here because we are not on a 589 * rqstp thread 590 */ 591 set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags); 592 svc_xprt_enqueue(&listen_xprt->sc_xprt); 593 } 594 595 /* 596 * Handles events generated on the listening endpoint. These events will be 597 * either be incoming connect requests or adapter removal events. 598 */ 599 static int rdma_listen_handler(struct rdma_cm_id *cma_id, 600 struct rdma_cm_event *event) 601 { 602 struct svcxprt_rdma *xprt = cma_id->context; 603 int ret = 0; 604 605 switch (event->event) { 606 case RDMA_CM_EVENT_CONNECT_REQUEST: 607 dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, " 608 "event=%d\n", cma_id, cma_id->context, event->event); 609 handle_connect_req(cma_id, 610 event->param.conn.initiator_depth); 611 break; 612 613 case RDMA_CM_EVENT_ESTABLISHED: 614 /* Accept complete */ 615 dprintk("svcrdma: Connection completed on LISTEN xprt=%p, " 616 "cm_id=%p\n", xprt, cma_id); 617 break; 618 619 case RDMA_CM_EVENT_DEVICE_REMOVAL: 620 dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n", 621 xprt, cma_id); 622 if (xprt) 623 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 624 break; 625 626 default: 627 dprintk("svcrdma: Unexpected event on listening endpoint %p, " 628 "event=%d\n", cma_id, event->event); 629 break; 630 } 631 632 return ret; 633 } 634 635 static int rdma_cma_handler(struct rdma_cm_id *cma_id, 636 struct rdma_cm_event *event) 637 { 638 struct svc_xprt *xprt = cma_id->context; 639 struct svcxprt_rdma *rdma = 640 container_of(xprt, struct svcxprt_rdma, sc_xprt); 641 switch (event->event) { 642 case RDMA_CM_EVENT_ESTABLISHED: 643 /* Accept complete */ 644 svc_xprt_get(xprt); 645 dprintk("svcrdma: Connection completed on DTO xprt=%p, " 646 "cm_id=%p\n", xprt, cma_id); 647 clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags); 648 svc_xprt_enqueue(xprt); 649 break; 650 case RDMA_CM_EVENT_DISCONNECTED: 651 dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n", 652 xprt, cma_id); 653 if (xprt) { 654 set_bit(XPT_CLOSE, &xprt->xpt_flags); 655 svc_xprt_enqueue(xprt); 656 svc_xprt_put(xprt); 657 } 658 break; 659 case RDMA_CM_EVENT_DEVICE_REMOVAL: 660 dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, " 661 "event=%d\n", cma_id, xprt, event->event); 662 if (xprt) { 663 set_bit(XPT_CLOSE, &xprt->xpt_flags); 664 svc_xprt_enqueue(xprt); 665 } 666 break; 667 default: 668 dprintk("svcrdma: Unexpected event on DTO endpoint %p, " 669 "event=%d\n", cma_id, event->event); 670 break; 671 } 672 return 0; 673 } 674 675 /* 676 * Create a listening RDMA service endpoint. 677 */ 678 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, 679 struct net *net, 680 struct sockaddr *sa, int salen, 681 int flags) 682 { 683 struct rdma_cm_id *listen_id; 684 struct svcxprt_rdma *cma_xprt; 685 struct svc_xprt *xprt; 686 int ret; 687 688 dprintk("svcrdma: Creating RDMA socket\n"); 689 if (sa->sa_family != AF_INET) { 690 dprintk("svcrdma: Address family %d is not supported.\n", sa->sa_family); 691 return ERR_PTR(-EAFNOSUPPORT); 692 } 693 cma_xprt = rdma_create_xprt(serv, 1); 694 if (!cma_xprt) 695 return ERR_PTR(-ENOMEM); 696 xprt = &cma_xprt->sc_xprt; 697 698 listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP, 699 IB_QPT_RC); 700 if (IS_ERR(listen_id)) { 701 ret = PTR_ERR(listen_id); 702 dprintk("svcrdma: rdma_create_id failed = %d\n", ret); 703 goto err0; 704 } 705 706 ret = rdma_bind_addr(listen_id, sa); 707 if (ret) { 708 dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret); 709 goto err1; 710 } 711 cma_xprt->sc_cm_id = listen_id; 712 713 ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG); 714 if (ret) { 715 dprintk("svcrdma: rdma_listen failed = %d\n", ret); 716 goto err1; 717 } 718 719 /* 720 * We need to use the address from the cm_id in case the 721 * caller specified 0 for the port number. 722 */ 723 sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr; 724 svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen); 725 726 return &cma_xprt->sc_xprt; 727 728 err1: 729 rdma_destroy_id(listen_id); 730 err0: 731 kfree(cma_xprt); 732 return ERR_PTR(ret); 733 } 734 735 static struct svc_rdma_fastreg_mr *rdma_alloc_frmr(struct svcxprt_rdma *xprt) 736 { 737 struct ib_mr *mr; 738 struct ib_fast_reg_page_list *pl; 739 struct svc_rdma_fastreg_mr *frmr; 740 741 frmr = kmalloc(sizeof(*frmr), GFP_KERNEL); 742 if (!frmr) 743 goto err; 744 745 mr = ib_alloc_fast_reg_mr(xprt->sc_pd, RPCSVC_MAXPAGES); 746 if (IS_ERR(mr)) 747 goto err_free_frmr; 748 749 pl = ib_alloc_fast_reg_page_list(xprt->sc_cm_id->device, 750 RPCSVC_MAXPAGES); 751 if (IS_ERR(pl)) 752 goto err_free_mr; 753 754 frmr->mr = mr; 755 frmr->page_list = pl; 756 INIT_LIST_HEAD(&frmr->frmr_list); 757 return frmr; 758 759 err_free_mr: 760 ib_dereg_mr(mr); 761 err_free_frmr: 762 kfree(frmr); 763 err: 764 return ERR_PTR(-ENOMEM); 765 } 766 767 static void rdma_dealloc_frmr_q(struct svcxprt_rdma *xprt) 768 { 769 struct svc_rdma_fastreg_mr *frmr; 770 771 while (!list_empty(&xprt->sc_frmr_q)) { 772 frmr = list_entry(xprt->sc_frmr_q.next, 773 struct svc_rdma_fastreg_mr, frmr_list); 774 list_del_init(&frmr->frmr_list); 775 ib_dereg_mr(frmr->mr); 776 ib_free_fast_reg_page_list(frmr->page_list); 777 kfree(frmr); 778 } 779 } 780 781 struct svc_rdma_fastreg_mr *svc_rdma_get_frmr(struct svcxprt_rdma *rdma) 782 { 783 struct svc_rdma_fastreg_mr *frmr = NULL; 784 785 spin_lock_bh(&rdma->sc_frmr_q_lock); 786 if (!list_empty(&rdma->sc_frmr_q)) { 787 frmr = list_entry(rdma->sc_frmr_q.next, 788 struct svc_rdma_fastreg_mr, frmr_list); 789 list_del_init(&frmr->frmr_list); 790 frmr->map_len = 0; 791 frmr->page_list_len = 0; 792 } 793 spin_unlock_bh(&rdma->sc_frmr_q_lock); 794 if (frmr) 795 return frmr; 796 797 return rdma_alloc_frmr(rdma); 798 } 799 800 static void frmr_unmap_dma(struct svcxprt_rdma *xprt, 801 struct svc_rdma_fastreg_mr *frmr) 802 { 803 int page_no; 804 for (page_no = 0; page_no < frmr->page_list_len; page_no++) { 805 dma_addr_t addr = frmr->page_list->page_list[page_no]; 806 if (ib_dma_mapping_error(frmr->mr->device, addr)) 807 continue; 808 atomic_dec(&xprt->sc_dma_used); 809 ib_dma_unmap_page(frmr->mr->device, addr, PAGE_SIZE, 810 frmr->direction); 811 } 812 } 813 814 void svc_rdma_put_frmr(struct svcxprt_rdma *rdma, 815 struct svc_rdma_fastreg_mr *frmr) 816 { 817 if (frmr) { 818 frmr_unmap_dma(rdma, frmr); 819 spin_lock_bh(&rdma->sc_frmr_q_lock); 820 BUG_ON(!list_empty(&frmr->frmr_list)); 821 list_add(&frmr->frmr_list, &rdma->sc_frmr_q); 822 spin_unlock_bh(&rdma->sc_frmr_q_lock); 823 } 824 } 825 826 /* 827 * This is the xpo_recvfrom function for listening endpoints. Its 828 * purpose is to accept incoming connections. The CMA callback handler 829 * has already created a new transport and attached it to the new CMA 830 * ID. 831 * 832 * There is a queue of pending connections hung on the listening 833 * transport. This queue contains the new svc_xprt structure. This 834 * function takes svc_xprt structures off the accept_q and completes 835 * the connection. 836 */ 837 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) 838 { 839 struct svcxprt_rdma *listen_rdma; 840 struct svcxprt_rdma *newxprt = NULL; 841 struct rdma_conn_param conn_param; 842 struct ib_qp_init_attr qp_attr; 843 struct ib_device_attr devattr; 844 int uninitialized_var(dma_mr_acc); 845 int need_dma_mr; 846 int ret; 847 int i; 848 849 listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); 850 clear_bit(XPT_CONN, &xprt->xpt_flags); 851 /* Get the next entry off the accept list */ 852 spin_lock_bh(&listen_rdma->sc_lock); 853 if (!list_empty(&listen_rdma->sc_accept_q)) { 854 newxprt = list_entry(listen_rdma->sc_accept_q.next, 855 struct svcxprt_rdma, sc_accept_q); 856 list_del_init(&newxprt->sc_accept_q); 857 } 858 if (!list_empty(&listen_rdma->sc_accept_q)) 859 set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags); 860 spin_unlock_bh(&listen_rdma->sc_lock); 861 if (!newxprt) 862 return NULL; 863 864 dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n", 865 newxprt, newxprt->sc_cm_id); 866 867 ret = ib_query_device(newxprt->sc_cm_id->device, &devattr); 868 if (ret) { 869 dprintk("svcrdma: could not query device attributes on " 870 "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret); 871 goto errout; 872 } 873 874 /* Qualify the transport resource defaults with the 875 * capabilities of this particular device */ 876 newxprt->sc_max_sge = min((size_t)devattr.max_sge, 877 (size_t)RPCSVC_MAXPAGES); 878 newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr, 879 (size_t)svcrdma_max_requests); 880 newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests; 881 882 /* 883 * Limit ORD based on client limit, local device limit, and 884 * configured svcrdma limit. 885 */ 886 newxprt->sc_ord = min_t(size_t, devattr.max_qp_rd_atom, newxprt->sc_ord); 887 newxprt->sc_ord = min_t(size_t, svcrdma_ord, newxprt->sc_ord); 888 889 newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device); 890 if (IS_ERR(newxprt->sc_pd)) { 891 dprintk("svcrdma: error creating PD for connect request\n"); 892 goto errout; 893 } 894 newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device, 895 sq_comp_handler, 896 cq_event_handler, 897 newxprt, 898 newxprt->sc_sq_depth, 899 0); 900 if (IS_ERR(newxprt->sc_sq_cq)) { 901 dprintk("svcrdma: error creating SQ CQ for connect request\n"); 902 goto errout; 903 } 904 newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device, 905 rq_comp_handler, 906 cq_event_handler, 907 newxprt, 908 newxprt->sc_max_requests, 909 0); 910 if (IS_ERR(newxprt->sc_rq_cq)) { 911 dprintk("svcrdma: error creating RQ CQ for connect request\n"); 912 goto errout; 913 } 914 915 memset(&qp_attr, 0, sizeof qp_attr); 916 qp_attr.event_handler = qp_event_handler; 917 qp_attr.qp_context = &newxprt->sc_xprt; 918 qp_attr.cap.max_send_wr = newxprt->sc_sq_depth; 919 qp_attr.cap.max_recv_wr = newxprt->sc_max_requests; 920 qp_attr.cap.max_send_sge = newxprt->sc_max_sge; 921 qp_attr.cap.max_recv_sge = newxprt->sc_max_sge; 922 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; 923 qp_attr.qp_type = IB_QPT_RC; 924 qp_attr.send_cq = newxprt->sc_sq_cq; 925 qp_attr.recv_cq = newxprt->sc_rq_cq; 926 dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n" 927 " cm_id->device=%p, sc_pd->device=%p\n" 928 " cap.max_send_wr = %d\n" 929 " cap.max_recv_wr = %d\n" 930 " cap.max_send_sge = %d\n" 931 " cap.max_recv_sge = %d\n", 932 newxprt->sc_cm_id, newxprt->sc_pd, 933 newxprt->sc_cm_id->device, newxprt->sc_pd->device, 934 qp_attr.cap.max_send_wr, 935 qp_attr.cap.max_recv_wr, 936 qp_attr.cap.max_send_sge, 937 qp_attr.cap.max_recv_sge); 938 939 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr); 940 if (ret) { 941 /* 942 * XXX: This is a hack. We need a xx_request_qp interface 943 * that will adjust the qp_attr's with a best-effort 944 * number 945 */ 946 qp_attr.cap.max_send_sge -= 2; 947 qp_attr.cap.max_recv_sge -= 2; 948 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, 949 &qp_attr); 950 if (ret) { 951 dprintk("svcrdma: failed to create QP, ret=%d\n", ret); 952 goto errout; 953 } 954 newxprt->sc_max_sge = qp_attr.cap.max_send_sge; 955 newxprt->sc_max_sge = qp_attr.cap.max_recv_sge; 956 newxprt->sc_sq_depth = qp_attr.cap.max_send_wr; 957 newxprt->sc_max_requests = qp_attr.cap.max_recv_wr; 958 } 959 newxprt->sc_qp = newxprt->sc_cm_id->qp; 960 961 /* 962 * Use the most secure set of MR resources based on the 963 * transport type and available memory management features in 964 * the device. Here's the table implemented below: 965 * 966 * Fast Global DMA Remote WR 967 * Reg LKEY MR Access 968 * Sup'd Sup'd Needed Needed 969 * 970 * IWARP N N Y Y 971 * N Y Y Y 972 * Y N Y N 973 * Y Y N - 974 * 975 * IB N N Y N 976 * N Y N - 977 * Y N Y N 978 * Y Y N - 979 * 980 * NB: iWARP requires remote write access for the data sink 981 * of an RDMA_READ. IB does not. 982 */ 983 if (devattr.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) { 984 newxprt->sc_frmr_pg_list_len = 985 devattr.max_fast_reg_page_list_len; 986 newxprt->sc_dev_caps |= SVCRDMA_DEVCAP_FAST_REG; 987 } 988 989 /* 990 * Determine if a DMA MR is required and if so, what privs are required 991 */ 992 switch (rdma_node_get_transport(newxprt->sc_cm_id->device->node_type)) { 993 case RDMA_TRANSPORT_IWARP: 994 newxprt->sc_dev_caps |= SVCRDMA_DEVCAP_READ_W_INV; 995 if (!(newxprt->sc_dev_caps & SVCRDMA_DEVCAP_FAST_REG)) { 996 need_dma_mr = 1; 997 dma_mr_acc = 998 (IB_ACCESS_LOCAL_WRITE | 999 IB_ACCESS_REMOTE_WRITE); 1000 } else if (!(devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)) { 1001 need_dma_mr = 1; 1002 dma_mr_acc = IB_ACCESS_LOCAL_WRITE; 1003 } else 1004 need_dma_mr = 0; 1005 break; 1006 case RDMA_TRANSPORT_IB: 1007 if (!(devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)) { 1008 need_dma_mr = 1; 1009 dma_mr_acc = IB_ACCESS_LOCAL_WRITE; 1010 } else 1011 need_dma_mr = 0; 1012 break; 1013 default: 1014 goto errout; 1015 } 1016 1017 /* Create the DMA MR if needed, otherwise, use the DMA LKEY */ 1018 if (need_dma_mr) { 1019 /* Register all of physical memory */ 1020 newxprt->sc_phys_mr = 1021 ib_get_dma_mr(newxprt->sc_pd, dma_mr_acc); 1022 if (IS_ERR(newxprt->sc_phys_mr)) { 1023 dprintk("svcrdma: Failed to create DMA MR ret=%d\n", 1024 ret); 1025 goto errout; 1026 } 1027 newxprt->sc_dma_lkey = newxprt->sc_phys_mr->lkey; 1028 } else 1029 newxprt->sc_dma_lkey = 1030 newxprt->sc_cm_id->device->local_dma_lkey; 1031 1032 /* Post receive buffers */ 1033 for (i = 0; i < newxprt->sc_max_requests; i++) { 1034 ret = svc_rdma_post_recv(newxprt); 1035 if (ret) { 1036 dprintk("svcrdma: failure posting receive buffers\n"); 1037 goto errout; 1038 } 1039 } 1040 1041 /* Swap out the handler */ 1042 newxprt->sc_cm_id->event_handler = rdma_cma_handler; 1043 1044 /* 1045 * Arm the CQs for the SQ and RQ before accepting so we can't 1046 * miss the first message 1047 */ 1048 ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP); 1049 ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP); 1050 1051 /* Accept Connection */ 1052 set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags); 1053 memset(&conn_param, 0, sizeof conn_param); 1054 conn_param.responder_resources = 0; 1055 conn_param.initiator_depth = newxprt->sc_ord; 1056 ret = rdma_accept(newxprt->sc_cm_id, &conn_param); 1057 if (ret) { 1058 dprintk("svcrdma: failed to accept new connection, ret=%d\n", 1059 ret); 1060 goto errout; 1061 } 1062 1063 dprintk("svcrdma: new connection %p accepted with the following " 1064 "attributes:\n" 1065 " local_ip : %pI4\n" 1066 " local_port : %d\n" 1067 " remote_ip : %pI4\n" 1068 " remote_port : %d\n" 1069 " max_sge : %d\n" 1070 " sq_depth : %d\n" 1071 " max_requests : %d\n" 1072 " ord : %d\n", 1073 newxprt, 1074 &((struct sockaddr_in *)&newxprt->sc_cm_id-> 1075 route.addr.src_addr)->sin_addr.s_addr, 1076 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id-> 1077 route.addr.src_addr)->sin_port), 1078 &((struct sockaddr_in *)&newxprt->sc_cm_id-> 1079 route.addr.dst_addr)->sin_addr.s_addr, 1080 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id-> 1081 route.addr.dst_addr)->sin_port), 1082 newxprt->sc_max_sge, 1083 newxprt->sc_sq_depth, 1084 newxprt->sc_max_requests, 1085 newxprt->sc_ord); 1086 1087 return &newxprt->sc_xprt; 1088 1089 errout: 1090 dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret); 1091 /* Take a reference in case the DTO handler runs */ 1092 svc_xprt_get(&newxprt->sc_xprt); 1093 if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp)) 1094 ib_destroy_qp(newxprt->sc_qp); 1095 rdma_destroy_id(newxprt->sc_cm_id); 1096 /* This call to put will destroy the transport */ 1097 svc_xprt_put(&newxprt->sc_xprt); 1098 return NULL; 1099 } 1100 1101 static void svc_rdma_release_rqst(struct svc_rqst *rqstp) 1102 { 1103 } 1104 1105 /* 1106 * When connected, an svc_xprt has at least two references: 1107 * 1108 * - A reference held by the cm_id between the ESTABLISHED and 1109 * DISCONNECTED events. If the remote peer disconnected first, this 1110 * reference could be gone. 1111 * 1112 * - A reference held by the svc_recv code that called this function 1113 * as part of close processing. 1114 * 1115 * At a minimum one references should still be held. 1116 */ 1117 static void svc_rdma_detach(struct svc_xprt *xprt) 1118 { 1119 struct svcxprt_rdma *rdma = 1120 container_of(xprt, struct svcxprt_rdma, sc_xprt); 1121 dprintk("svc: svc_rdma_detach(%p)\n", xprt); 1122 1123 /* Disconnect and flush posted WQE */ 1124 rdma_disconnect(rdma->sc_cm_id); 1125 } 1126 1127 static void __svc_rdma_free(struct work_struct *work) 1128 { 1129 struct svcxprt_rdma *rdma = 1130 container_of(work, struct svcxprt_rdma, sc_work); 1131 dprintk("svcrdma: svc_rdma_free(%p)\n", rdma); 1132 1133 /* We should only be called from kref_put */ 1134 BUG_ON(atomic_read(&rdma->sc_xprt.xpt_ref.refcount) != 0); 1135 1136 /* 1137 * Destroy queued, but not processed read completions. Note 1138 * that this cleanup has to be done before destroying the 1139 * cm_id because the device ptr is needed to unmap the dma in 1140 * svc_rdma_put_context. 1141 */ 1142 while (!list_empty(&rdma->sc_read_complete_q)) { 1143 struct svc_rdma_op_ctxt *ctxt; 1144 ctxt = list_entry(rdma->sc_read_complete_q.next, 1145 struct svc_rdma_op_ctxt, 1146 dto_q); 1147 list_del_init(&ctxt->dto_q); 1148 svc_rdma_put_context(ctxt, 1); 1149 } 1150 1151 /* Destroy queued, but not processed recv completions */ 1152 while (!list_empty(&rdma->sc_rq_dto_q)) { 1153 struct svc_rdma_op_ctxt *ctxt; 1154 ctxt = list_entry(rdma->sc_rq_dto_q.next, 1155 struct svc_rdma_op_ctxt, 1156 dto_q); 1157 list_del_init(&ctxt->dto_q); 1158 svc_rdma_put_context(ctxt, 1); 1159 } 1160 1161 /* Warn if we leaked a resource or under-referenced */ 1162 WARN_ON(atomic_read(&rdma->sc_ctxt_used) != 0); 1163 WARN_ON(atomic_read(&rdma->sc_dma_used) != 0); 1164 1165 /* De-allocate fastreg mr */ 1166 rdma_dealloc_frmr_q(rdma); 1167 1168 /* Destroy the QP if present (not a listener) */ 1169 if (rdma->sc_qp && !IS_ERR(rdma->sc_qp)) 1170 ib_destroy_qp(rdma->sc_qp); 1171 1172 if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq)) 1173 ib_destroy_cq(rdma->sc_sq_cq); 1174 1175 if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq)) 1176 ib_destroy_cq(rdma->sc_rq_cq); 1177 1178 if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr)) 1179 ib_dereg_mr(rdma->sc_phys_mr); 1180 1181 if (rdma->sc_pd && !IS_ERR(rdma->sc_pd)) 1182 ib_dealloc_pd(rdma->sc_pd); 1183 1184 /* Destroy the CM ID */ 1185 rdma_destroy_id(rdma->sc_cm_id); 1186 1187 kfree(rdma); 1188 } 1189 1190 static void svc_rdma_free(struct svc_xprt *xprt) 1191 { 1192 struct svcxprt_rdma *rdma = 1193 container_of(xprt, struct svcxprt_rdma, sc_xprt); 1194 INIT_WORK(&rdma->sc_work, __svc_rdma_free); 1195 queue_work(svc_rdma_wq, &rdma->sc_work); 1196 } 1197 1198 static int svc_rdma_has_wspace(struct svc_xprt *xprt) 1199 { 1200 struct svcxprt_rdma *rdma = 1201 container_of(xprt, struct svcxprt_rdma, sc_xprt); 1202 1203 /* 1204 * If there are fewer SQ WR available than required to send a 1205 * simple response, return false. 1206 */ 1207 if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3)) 1208 return 0; 1209 1210 /* 1211 * ...or there are already waiters on the SQ, 1212 * return false. 1213 */ 1214 if (waitqueue_active(&rdma->sc_send_wait)) 1215 return 0; 1216 1217 /* Otherwise return true. */ 1218 return 1; 1219 } 1220 1221 /* 1222 * Attempt to register the kvec representing the RPC memory with the 1223 * device. 1224 * 1225 * Returns: 1226 * NULL : The device does not support fastreg or there were no more 1227 * fastreg mr. 1228 * frmr : The kvec register request was successfully posted. 1229 * <0 : An error was encountered attempting to register the kvec. 1230 */ 1231 int svc_rdma_fastreg(struct svcxprt_rdma *xprt, 1232 struct svc_rdma_fastreg_mr *frmr) 1233 { 1234 struct ib_send_wr fastreg_wr; 1235 u8 key; 1236 1237 /* Bump the key */ 1238 key = (u8)(frmr->mr->lkey & 0x000000FF); 1239 ib_update_fast_reg_key(frmr->mr, ++key); 1240 1241 /* Prepare FASTREG WR */ 1242 memset(&fastreg_wr, 0, sizeof fastreg_wr); 1243 fastreg_wr.opcode = IB_WR_FAST_REG_MR; 1244 fastreg_wr.send_flags = IB_SEND_SIGNALED; 1245 fastreg_wr.wr.fast_reg.iova_start = (unsigned long)frmr->kva; 1246 fastreg_wr.wr.fast_reg.page_list = frmr->page_list; 1247 fastreg_wr.wr.fast_reg.page_list_len = frmr->page_list_len; 1248 fastreg_wr.wr.fast_reg.page_shift = PAGE_SHIFT; 1249 fastreg_wr.wr.fast_reg.length = frmr->map_len; 1250 fastreg_wr.wr.fast_reg.access_flags = frmr->access_flags; 1251 fastreg_wr.wr.fast_reg.rkey = frmr->mr->lkey; 1252 return svc_rdma_send(xprt, &fastreg_wr); 1253 } 1254 1255 int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr) 1256 { 1257 struct ib_send_wr *bad_wr, *n_wr; 1258 int wr_count; 1259 int i; 1260 int ret; 1261 1262 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags)) 1263 return -ENOTCONN; 1264 1265 BUG_ON(wr->send_flags != IB_SEND_SIGNALED); 1266 wr_count = 1; 1267 for (n_wr = wr->next; n_wr; n_wr = n_wr->next) 1268 wr_count++; 1269 1270 /* If the SQ is full, wait until an SQ entry is available */ 1271 while (1) { 1272 spin_lock_bh(&xprt->sc_lock); 1273 if (xprt->sc_sq_depth < atomic_read(&xprt->sc_sq_count) + wr_count) { 1274 spin_unlock_bh(&xprt->sc_lock); 1275 atomic_inc(&rdma_stat_sq_starve); 1276 1277 /* See if we can opportunistically reap SQ WR to make room */ 1278 sq_cq_reap(xprt); 1279 1280 /* Wait until SQ WR available if SQ still full */ 1281 wait_event(xprt->sc_send_wait, 1282 atomic_read(&xprt->sc_sq_count) < 1283 xprt->sc_sq_depth); 1284 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags)) 1285 return -ENOTCONN; 1286 continue; 1287 } 1288 /* Take a transport ref for each WR posted */ 1289 for (i = 0; i < wr_count; i++) 1290 svc_xprt_get(&xprt->sc_xprt); 1291 1292 /* Bump used SQ WR count and post */ 1293 atomic_add(wr_count, &xprt->sc_sq_count); 1294 ret = ib_post_send(xprt->sc_qp, wr, &bad_wr); 1295 if (ret) { 1296 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 1297 atomic_sub(wr_count, &xprt->sc_sq_count); 1298 for (i = 0; i < wr_count; i ++) 1299 svc_xprt_put(&xprt->sc_xprt); 1300 dprintk("svcrdma: failed to post SQ WR rc=%d, " 1301 "sc_sq_count=%d, sc_sq_depth=%d\n", 1302 ret, atomic_read(&xprt->sc_sq_count), 1303 xprt->sc_sq_depth); 1304 } 1305 spin_unlock_bh(&xprt->sc_lock); 1306 if (ret) 1307 wake_up(&xprt->sc_send_wait); 1308 break; 1309 } 1310 return ret; 1311 } 1312 1313 void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, 1314 enum rpcrdma_errcode err) 1315 { 1316 struct ib_send_wr err_wr; 1317 struct page *p; 1318 struct svc_rdma_op_ctxt *ctxt; 1319 u32 *va; 1320 int length; 1321 int ret; 1322 1323 p = svc_rdma_get_page(); 1324 va = page_address(p); 1325 1326 /* XDR encode error */ 1327 length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va); 1328 1329 ctxt = svc_rdma_get_context(xprt); 1330 ctxt->direction = DMA_FROM_DEVICE; 1331 ctxt->count = 1; 1332 ctxt->pages[0] = p; 1333 1334 /* Prepare SGE for local address */ 1335 ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device, 1336 p, 0, length, DMA_FROM_DEVICE); 1337 if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) { 1338 put_page(p); 1339 svc_rdma_put_context(ctxt, 1); 1340 return; 1341 } 1342 atomic_inc(&xprt->sc_dma_used); 1343 ctxt->sge[0].lkey = xprt->sc_dma_lkey; 1344 ctxt->sge[0].length = length; 1345 1346 /* Prepare SEND WR */ 1347 memset(&err_wr, 0, sizeof err_wr); 1348 ctxt->wr_op = IB_WR_SEND; 1349 err_wr.wr_id = (unsigned long)ctxt; 1350 err_wr.sg_list = ctxt->sge; 1351 err_wr.num_sge = 1; 1352 err_wr.opcode = IB_WR_SEND; 1353 err_wr.send_flags = IB_SEND_SIGNALED; 1354 1355 /* Post It */ 1356 ret = svc_rdma_send(xprt, &err_wr); 1357 if (ret) { 1358 dprintk("svcrdma: Error %d posting send for protocol error\n", 1359 ret); 1360 svc_rdma_unmap_dma(ctxt); 1361 svc_rdma_put_context(ctxt, 1); 1362 } 1363 } 1364