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/interrupt.h> 46 #include <linux/sched.h> 47 #include <linux/slab.h> 48 #include <linux/spinlock.h> 49 #include <linux/workqueue.h> 50 #include <rdma/ib_verbs.h> 51 #include <rdma/rdma_cm.h> 52 #include <linux/sunrpc/svc_rdma.h> 53 #include <linux/export.h> 54 55 #define RPCDBG_FACILITY RPCDBG_SVCXPRT 56 57 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, 58 struct net *net, 59 struct sockaddr *sa, int salen, 60 int flags); 61 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt); 62 static void svc_rdma_release_rqst(struct svc_rqst *); 63 static void dto_tasklet_func(unsigned long data); 64 static void svc_rdma_detach(struct svc_xprt *xprt); 65 static void svc_rdma_free(struct svc_xprt *xprt); 66 static int svc_rdma_has_wspace(struct svc_xprt *xprt); 67 static void rq_cq_reap(struct svcxprt_rdma *xprt); 68 static void sq_cq_reap(struct svcxprt_rdma *xprt); 69 70 static DECLARE_TASKLET(dto_tasklet, dto_tasklet_func, 0UL); 71 static DEFINE_SPINLOCK(dto_lock); 72 static LIST_HEAD(dto_xprt_q); 73 74 static struct svc_xprt_ops svc_rdma_ops = { 75 .xpo_create = svc_rdma_create, 76 .xpo_recvfrom = svc_rdma_recvfrom, 77 .xpo_sendto = svc_rdma_sendto, 78 .xpo_release_rqst = svc_rdma_release_rqst, 79 .xpo_detach = svc_rdma_detach, 80 .xpo_free = svc_rdma_free, 81 .xpo_prep_reply_hdr = svc_rdma_prep_reply_hdr, 82 .xpo_has_wspace = svc_rdma_has_wspace, 83 .xpo_accept = svc_rdma_accept, 84 }; 85 86 struct svc_xprt_class svc_rdma_class = { 87 .xcl_name = "rdma", 88 .xcl_owner = THIS_MODULE, 89 .xcl_ops = &svc_rdma_ops, 90 .xcl_max_payload = RPCSVC_MAXPAYLOAD_TCP, 91 }; 92 93 /* WR context cache. Created in svc_rdma.c */ 94 extern struct kmem_cache *svc_rdma_ctxt_cachep; 95 96 /* Workqueue created in svc_rdma.c */ 97 extern struct workqueue_struct *svc_rdma_wq; 98 99 struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *xprt) 100 { 101 struct svc_rdma_op_ctxt *ctxt; 102 103 while (1) { 104 ctxt = kmem_cache_alloc(svc_rdma_ctxt_cachep, GFP_KERNEL); 105 if (ctxt) 106 break; 107 schedule_timeout_uninterruptible(msecs_to_jiffies(500)); 108 } 109 ctxt->xprt = xprt; 110 INIT_LIST_HEAD(&ctxt->dto_q); 111 ctxt->count = 0; 112 ctxt->frmr = NULL; 113 atomic_inc(&xprt->sc_ctxt_used); 114 return ctxt; 115 } 116 117 void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt) 118 { 119 struct svcxprt_rdma *xprt = ctxt->xprt; 120 int i; 121 for (i = 0; i < ctxt->count && ctxt->sge[i].length; i++) { 122 /* 123 * Unmap the DMA addr in the SGE if the lkey matches 124 * the sc_dma_lkey, otherwise, ignore it since it is 125 * an FRMR lkey and will be unmapped later when the 126 * last WR that uses it completes. 127 */ 128 if (ctxt->sge[i].lkey == xprt->sc_dma_lkey) { 129 atomic_dec(&xprt->sc_dma_used); 130 ib_dma_unmap_page(xprt->sc_cm_id->device, 131 ctxt->sge[i].addr, 132 ctxt->sge[i].length, 133 ctxt->direction); 134 } 135 } 136 } 137 138 void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages) 139 { 140 struct svcxprt_rdma *xprt; 141 int i; 142 143 BUG_ON(!ctxt); 144 xprt = ctxt->xprt; 145 if (free_pages) 146 for (i = 0; i < ctxt->count; i++) 147 put_page(ctxt->pages[i]); 148 149 kmem_cache_free(svc_rdma_ctxt_cachep, ctxt); 150 atomic_dec(&xprt->sc_ctxt_used); 151 } 152 153 /* Temporary NFS request map cache. Created in svc_rdma.c */ 154 extern struct kmem_cache *svc_rdma_map_cachep; 155 156 /* 157 * Temporary NFS req mappings are shared across all transport 158 * instances. These are short lived and should be bounded by the number 159 * of concurrent server threads * depth of the SQ. 160 */ 161 struct svc_rdma_req_map *svc_rdma_get_req_map(void) 162 { 163 struct svc_rdma_req_map *map; 164 while (1) { 165 map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL); 166 if (map) 167 break; 168 schedule_timeout_uninterruptible(msecs_to_jiffies(500)); 169 } 170 map->count = 0; 171 map->frmr = NULL; 172 return map; 173 } 174 175 void svc_rdma_put_req_map(struct svc_rdma_req_map *map) 176 { 177 kmem_cache_free(svc_rdma_map_cachep, map); 178 } 179 180 /* ib_cq event handler */ 181 static void cq_event_handler(struct ib_event *event, void *context) 182 { 183 struct svc_xprt *xprt = context; 184 dprintk("svcrdma: received CQ event id=%d, context=%p\n", 185 event->event, context); 186 set_bit(XPT_CLOSE, &xprt->xpt_flags); 187 } 188 189 /* QP event handler */ 190 static void qp_event_handler(struct ib_event *event, void *context) 191 { 192 struct svc_xprt *xprt = context; 193 194 switch (event->event) { 195 /* These are considered benign events */ 196 case IB_EVENT_PATH_MIG: 197 case IB_EVENT_COMM_EST: 198 case IB_EVENT_SQ_DRAINED: 199 case IB_EVENT_QP_LAST_WQE_REACHED: 200 dprintk("svcrdma: QP event %d received for QP=%p\n", 201 event->event, event->element.qp); 202 break; 203 /* These are considered fatal events */ 204 case IB_EVENT_PATH_MIG_ERR: 205 case IB_EVENT_QP_FATAL: 206 case IB_EVENT_QP_REQ_ERR: 207 case IB_EVENT_QP_ACCESS_ERR: 208 case IB_EVENT_DEVICE_FATAL: 209 default: 210 dprintk("svcrdma: QP ERROR event %d received for QP=%p, " 211 "closing transport\n", 212 event->event, event->element.qp); 213 set_bit(XPT_CLOSE, &xprt->xpt_flags); 214 break; 215 } 216 } 217 218 /* 219 * Data Transfer Operation Tasklet 220 * 221 * Walks a list of transports with I/O pending, removing entries as 222 * they are added to the server's I/O pending list. Two bits indicate 223 * if SQ, RQ, or both have I/O pending. The dto_lock is an irqsave 224 * spinlock that serializes access to the transport list with the RQ 225 * and SQ interrupt handlers. 226 */ 227 static void dto_tasklet_func(unsigned long data) 228 { 229 struct svcxprt_rdma *xprt; 230 unsigned long flags; 231 232 spin_lock_irqsave(&dto_lock, flags); 233 while (!list_empty(&dto_xprt_q)) { 234 xprt = list_entry(dto_xprt_q.next, 235 struct svcxprt_rdma, sc_dto_q); 236 list_del_init(&xprt->sc_dto_q); 237 spin_unlock_irqrestore(&dto_lock, flags); 238 239 rq_cq_reap(xprt); 240 sq_cq_reap(xprt); 241 242 svc_xprt_put(&xprt->sc_xprt); 243 spin_lock_irqsave(&dto_lock, flags); 244 } 245 spin_unlock_irqrestore(&dto_lock, flags); 246 } 247 248 /* 249 * Receive Queue Completion Handler 250 * 251 * Since an RQ completion handler is called on interrupt context, we 252 * need to defer the handling of the I/O to a tasklet 253 */ 254 static void rq_comp_handler(struct ib_cq *cq, void *cq_context) 255 { 256 struct svcxprt_rdma *xprt = cq_context; 257 unsigned long flags; 258 259 /* Guard against unconditional flush call for destroyed QP */ 260 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0) 261 return; 262 263 /* 264 * Set the bit regardless of whether or not it's on the list 265 * because it may be on the list already due to an SQ 266 * completion. 267 */ 268 set_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags); 269 270 /* 271 * If this transport is not already on the DTO transport queue, 272 * add it 273 */ 274 spin_lock_irqsave(&dto_lock, flags); 275 if (list_empty(&xprt->sc_dto_q)) { 276 svc_xprt_get(&xprt->sc_xprt); 277 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q); 278 } 279 spin_unlock_irqrestore(&dto_lock, flags); 280 281 /* Tasklet does all the work to avoid irqsave locks. */ 282 tasklet_schedule(&dto_tasklet); 283 } 284 285 /* 286 * rq_cq_reap - Process the RQ CQ. 287 * 288 * Take all completing WC off the CQE and enqueue the associated DTO 289 * context on the dto_q for the transport. 290 * 291 * Note that caller must hold a transport reference. 292 */ 293 static void rq_cq_reap(struct svcxprt_rdma *xprt) 294 { 295 int ret; 296 struct ib_wc wc; 297 struct svc_rdma_op_ctxt *ctxt = NULL; 298 299 if (!test_and_clear_bit(RDMAXPRT_RQ_PENDING, &xprt->sc_flags)) 300 return; 301 302 ib_req_notify_cq(xprt->sc_rq_cq, IB_CQ_NEXT_COMP); 303 atomic_inc(&rdma_stat_rq_poll); 304 305 while ((ret = ib_poll_cq(xprt->sc_rq_cq, 1, &wc)) > 0) { 306 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id; 307 ctxt->wc_status = wc.status; 308 ctxt->byte_len = wc.byte_len; 309 svc_rdma_unmap_dma(ctxt); 310 if (wc.status != IB_WC_SUCCESS) { 311 /* Close the transport */ 312 dprintk("svcrdma: transport closing putting ctxt %p\n", ctxt); 313 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 314 svc_rdma_put_context(ctxt, 1); 315 svc_xprt_put(&xprt->sc_xprt); 316 continue; 317 } 318 spin_lock_bh(&xprt->sc_rq_dto_lock); 319 list_add_tail(&ctxt->dto_q, &xprt->sc_rq_dto_q); 320 spin_unlock_bh(&xprt->sc_rq_dto_lock); 321 svc_xprt_put(&xprt->sc_xprt); 322 } 323 324 if (ctxt) 325 atomic_inc(&rdma_stat_rq_prod); 326 327 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags); 328 /* 329 * If data arrived before established event, 330 * don't enqueue. This defers RPC I/O until the 331 * RDMA connection is complete. 332 */ 333 if (!test_bit(RDMAXPRT_CONN_PENDING, &xprt->sc_flags)) 334 svc_xprt_enqueue(&xprt->sc_xprt); 335 } 336 337 /* 338 * Process a completion context 339 */ 340 static void process_context(struct svcxprt_rdma *xprt, 341 struct svc_rdma_op_ctxt *ctxt) 342 { 343 svc_rdma_unmap_dma(ctxt); 344 345 switch (ctxt->wr_op) { 346 case IB_WR_SEND: 347 if (test_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags)) 348 svc_rdma_put_frmr(xprt, ctxt->frmr); 349 svc_rdma_put_context(ctxt, 1); 350 break; 351 352 case IB_WR_RDMA_WRITE: 353 svc_rdma_put_context(ctxt, 0); 354 break; 355 356 case IB_WR_RDMA_READ: 357 case IB_WR_RDMA_READ_WITH_INV: 358 if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) { 359 struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr; 360 BUG_ON(!read_hdr); 361 if (test_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags)) 362 svc_rdma_put_frmr(xprt, ctxt->frmr); 363 spin_lock_bh(&xprt->sc_rq_dto_lock); 364 set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags); 365 list_add_tail(&read_hdr->dto_q, 366 &xprt->sc_read_complete_q); 367 spin_unlock_bh(&xprt->sc_rq_dto_lock); 368 svc_xprt_enqueue(&xprt->sc_xprt); 369 } 370 svc_rdma_put_context(ctxt, 0); 371 break; 372 373 default: 374 printk(KERN_ERR "svcrdma: unexpected completion type, " 375 "opcode=%d\n", 376 ctxt->wr_op); 377 break; 378 } 379 } 380 381 /* 382 * Send Queue Completion Handler - potentially called on interrupt context. 383 * 384 * Note that caller must hold a transport reference. 385 */ 386 static void sq_cq_reap(struct svcxprt_rdma *xprt) 387 { 388 struct svc_rdma_op_ctxt *ctxt = NULL; 389 struct ib_wc wc; 390 struct ib_cq *cq = xprt->sc_sq_cq; 391 int ret; 392 393 if (!test_and_clear_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags)) 394 return; 395 396 ib_req_notify_cq(xprt->sc_sq_cq, IB_CQ_NEXT_COMP); 397 atomic_inc(&rdma_stat_sq_poll); 398 while ((ret = ib_poll_cq(cq, 1, &wc)) > 0) { 399 if (wc.status != IB_WC_SUCCESS) 400 /* Close the transport */ 401 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 402 403 /* Decrement used SQ WR count */ 404 atomic_dec(&xprt->sc_sq_count); 405 wake_up(&xprt->sc_send_wait); 406 407 ctxt = (struct svc_rdma_op_ctxt *)(unsigned long)wc.wr_id; 408 if (ctxt) 409 process_context(xprt, ctxt); 410 411 svc_xprt_put(&xprt->sc_xprt); 412 } 413 414 if (ctxt) 415 atomic_inc(&rdma_stat_sq_prod); 416 } 417 418 static void sq_comp_handler(struct ib_cq *cq, void *cq_context) 419 { 420 struct svcxprt_rdma *xprt = cq_context; 421 unsigned long flags; 422 423 /* Guard against unconditional flush call for destroyed QP */ 424 if (atomic_read(&xprt->sc_xprt.xpt_ref.refcount)==0) 425 return; 426 427 /* 428 * Set the bit regardless of whether or not it's on the list 429 * because it may be on the list already due to an RQ 430 * completion. 431 */ 432 set_bit(RDMAXPRT_SQ_PENDING, &xprt->sc_flags); 433 434 /* 435 * If this transport is not already on the DTO transport queue, 436 * add it 437 */ 438 spin_lock_irqsave(&dto_lock, flags); 439 if (list_empty(&xprt->sc_dto_q)) { 440 svc_xprt_get(&xprt->sc_xprt); 441 list_add_tail(&xprt->sc_dto_q, &dto_xprt_q); 442 } 443 spin_unlock_irqrestore(&dto_lock, flags); 444 445 /* Tasklet does all the work to avoid irqsave locks. */ 446 tasklet_schedule(&dto_tasklet); 447 } 448 449 static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv, 450 int listener) 451 { 452 struct svcxprt_rdma *cma_xprt = kzalloc(sizeof *cma_xprt, GFP_KERNEL); 453 454 if (!cma_xprt) 455 return NULL; 456 svc_xprt_init(&svc_rdma_class, &cma_xprt->sc_xprt, serv); 457 INIT_LIST_HEAD(&cma_xprt->sc_accept_q); 458 INIT_LIST_HEAD(&cma_xprt->sc_dto_q); 459 INIT_LIST_HEAD(&cma_xprt->sc_rq_dto_q); 460 INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q); 461 INIT_LIST_HEAD(&cma_xprt->sc_frmr_q); 462 init_waitqueue_head(&cma_xprt->sc_send_wait); 463 464 spin_lock_init(&cma_xprt->sc_lock); 465 spin_lock_init(&cma_xprt->sc_rq_dto_lock); 466 spin_lock_init(&cma_xprt->sc_frmr_q_lock); 467 468 cma_xprt->sc_ord = svcrdma_ord; 469 470 cma_xprt->sc_max_req_size = svcrdma_max_req_size; 471 cma_xprt->sc_max_requests = svcrdma_max_requests; 472 cma_xprt->sc_sq_depth = svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT; 473 atomic_set(&cma_xprt->sc_sq_count, 0); 474 atomic_set(&cma_xprt->sc_ctxt_used, 0); 475 476 if (listener) 477 set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags); 478 479 return cma_xprt; 480 } 481 482 struct page *svc_rdma_get_page(void) 483 { 484 struct page *page; 485 486 while ((page = alloc_page(GFP_KERNEL)) == NULL) { 487 /* If we can't get memory, wait a bit and try again */ 488 printk(KERN_INFO "svcrdma: out of memory...retrying in 1000 " 489 "jiffies.\n"); 490 schedule_timeout_uninterruptible(msecs_to_jiffies(1000)); 491 } 492 return page; 493 } 494 495 int svc_rdma_post_recv(struct svcxprt_rdma *xprt) 496 { 497 struct ib_recv_wr recv_wr, *bad_recv_wr; 498 struct svc_rdma_op_ctxt *ctxt; 499 struct page *page; 500 dma_addr_t pa; 501 int sge_no; 502 int buflen; 503 int ret; 504 505 ctxt = svc_rdma_get_context(xprt); 506 buflen = 0; 507 ctxt->direction = DMA_FROM_DEVICE; 508 for (sge_no = 0; buflen < xprt->sc_max_req_size; sge_no++) { 509 BUG_ON(sge_no >= xprt->sc_max_sge); 510 page = svc_rdma_get_page(); 511 ctxt->pages[sge_no] = page; 512 pa = ib_dma_map_page(xprt->sc_cm_id->device, 513 page, 0, PAGE_SIZE, 514 DMA_FROM_DEVICE); 515 if (ib_dma_mapping_error(xprt->sc_cm_id->device, pa)) 516 goto err_put_ctxt; 517 atomic_inc(&xprt->sc_dma_used); 518 ctxt->sge[sge_no].addr = pa; 519 ctxt->sge[sge_no].length = PAGE_SIZE; 520 ctxt->sge[sge_no].lkey = xprt->sc_dma_lkey; 521 ctxt->count = sge_no + 1; 522 buflen += PAGE_SIZE; 523 } 524 recv_wr.next = NULL; 525 recv_wr.sg_list = &ctxt->sge[0]; 526 recv_wr.num_sge = ctxt->count; 527 recv_wr.wr_id = (u64)(unsigned long)ctxt; 528 529 svc_xprt_get(&xprt->sc_xprt); 530 ret = ib_post_recv(xprt->sc_qp, &recv_wr, &bad_recv_wr); 531 if (ret) { 532 svc_rdma_unmap_dma(ctxt); 533 svc_rdma_put_context(ctxt, 1); 534 svc_xprt_put(&xprt->sc_xprt); 535 } 536 return ret; 537 538 err_put_ctxt: 539 svc_rdma_unmap_dma(ctxt); 540 svc_rdma_put_context(ctxt, 1); 541 return -ENOMEM; 542 } 543 544 /* 545 * This function handles the CONNECT_REQUEST event on a listening 546 * endpoint. It is passed the cma_id for the _new_ connection. The context in 547 * this cma_id is inherited from the listening cma_id and is the svc_xprt 548 * structure for the listening endpoint. 549 * 550 * This function creates a new xprt for the new connection and enqueues it on 551 * the accept queue for the listent xprt. When the listen thread is kicked, it 552 * will call the recvfrom method on the listen xprt which will accept the new 553 * connection. 554 */ 555 static void handle_connect_req(struct rdma_cm_id *new_cma_id, size_t client_ird) 556 { 557 struct svcxprt_rdma *listen_xprt = new_cma_id->context; 558 struct svcxprt_rdma *newxprt; 559 struct sockaddr *sa; 560 561 /* Create a new transport */ 562 newxprt = rdma_create_xprt(listen_xprt->sc_xprt.xpt_server, 0); 563 if (!newxprt) { 564 dprintk("svcrdma: failed to create new transport\n"); 565 return; 566 } 567 newxprt->sc_cm_id = new_cma_id; 568 new_cma_id->context = newxprt; 569 dprintk("svcrdma: Creating newxprt=%p, cm_id=%p, listenxprt=%p\n", 570 newxprt, newxprt->sc_cm_id, listen_xprt); 571 572 /* Save client advertised inbound read limit for use later in accept. */ 573 newxprt->sc_ord = client_ird; 574 575 /* Set the local and remote addresses in the transport */ 576 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.dst_addr; 577 svc_xprt_set_remote(&newxprt->sc_xprt, sa, svc_addr_len(sa)); 578 sa = (struct sockaddr *)&newxprt->sc_cm_id->route.addr.src_addr; 579 svc_xprt_set_local(&newxprt->sc_xprt, sa, svc_addr_len(sa)); 580 581 /* 582 * Enqueue the new transport on the accept queue of the listening 583 * transport 584 */ 585 spin_lock_bh(&listen_xprt->sc_lock); 586 list_add_tail(&newxprt->sc_accept_q, &listen_xprt->sc_accept_q); 587 spin_unlock_bh(&listen_xprt->sc_lock); 588 589 /* 590 * Can't use svc_xprt_received here because we are not on a 591 * rqstp thread 592 */ 593 set_bit(XPT_CONN, &listen_xprt->sc_xprt.xpt_flags); 594 svc_xprt_enqueue(&listen_xprt->sc_xprt); 595 } 596 597 /* 598 * Handles events generated on the listening endpoint. These events will be 599 * either be incoming connect requests or adapter removal events. 600 */ 601 static int rdma_listen_handler(struct rdma_cm_id *cma_id, 602 struct rdma_cm_event *event) 603 { 604 struct svcxprt_rdma *xprt = cma_id->context; 605 int ret = 0; 606 607 switch (event->event) { 608 case RDMA_CM_EVENT_CONNECT_REQUEST: 609 dprintk("svcrdma: Connect request on cma_id=%p, xprt = %p, " 610 "event=%d\n", cma_id, cma_id->context, event->event); 611 handle_connect_req(cma_id, 612 event->param.conn.initiator_depth); 613 break; 614 615 case RDMA_CM_EVENT_ESTABLISHED: 616 /* Accept complete */ 617 dprintk("svcrdma: Connection completed on LISTEN xprt=%p, " 618 "cm_id=%p\n", xprt, cma_id); 619 break; 620 621 case RDMA_CM_EVENT_DEVICE_REMOVAL: 622 dprintk("svcrdma: Device removal xprt=%p, cm_id=%p\n", 623 xprt, cma_id); 624 if (xprt) 625 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 626 break; 627 628 default: 629 dprintk("svcrdma: Unexpected event on listening endpoint %p, " 630 "event=%d\n", cma_id, event->event); 631 break; 632 } 633 634 return ret; 635 } 636 637 static int rdma_cma_handler(struct rdma_cm_id *cma_id, 638 struct rdma_cm_event *event) 639 { 640 struct svc_xprt *xprt = cma_id->context; 641 struct svcxprt_rdma *rdma = 642 container_of(xprt, struct svcxprt_rdma, sc_xprt); 643 switch (event->event) { 644 case RDMA_CM_EVENT_ESTABLISHED: 645 /* Accept complete */ 646 svc_xprt_get(xprt); 647 dprintk("svcrdma: Connection completed on DTO xprt=%p, " 648 "cm_id=%p\n", xprt, cma_id); 649 clear_bit(RDMAXPRT_CONN_PENDING, &rdma->sc_flags); 650 svc_xprt_enqueue(xprt); 651 break; 652 case RDMA_CM_EVENT_DISCONNECTED: 653 dprintk("svcrdma: Disconnect on DTO xprt=%p, cm_id=%p\n", 654 xprt, cma_id); 655 if (xprt) { 656 set_bit(XPT_CLOSE, &xprt->xpt_flags); 657 svc_xprt_enqueue(xprt); 658 svc_xprt_put(xprt); 659 } 660 break; 661 case RDMA_CM_EVENT_DEVICE_REMOVAL: 662 dprintk("svcrdma: Device removal cma_id=%p, xprt = %p, " 663 "event=%d\n", cma_id, xprt, event->event); 664 if (xprt) { 665 set_bit(XPT_CLOSE, &xprt->xpt_flags); 666 svc_xprt_enqueue(xprt); 667 } 668 break; 669 default: 670 dprintk("svcrdma: Unexpected event on DTO endpoint %p, " 671 "event=%d\n", cma_id, event->event); 672 break; 673 } 674 return 0; 675 } 676 677 /* 678 * Create a listening RDMA service endpoint. 679 */ 680 static struct svc_xprt *svc_rdma_create(struct svc_serv *serv, 681 struct net *net, 682 struct sockaddr *sa, int salen, 683 int flags) 684 { 685 struct rdma_cm_id *listen_id; 686 struct svcxprt_rdma *cma_xprt; 687 struct svc_xprt *xprt; 688 int ret; 689 690 dprintk("svcrdma: Creating RDMA socket\n"); 691 if (sa->sa_family != AF_INET) { 692 dprintk("svcrdma: Address family %d is not supported.\n", sa->sa_family); 693 return ERR_PTR(-EAFNOSUPPORT); 694 } 695 cma_xprt = rdma_create_xprt(serv, 1); 696 if (!cma_xprt) 697 return ERR_PTR(-ENOMEM); 698 xprt = &cma_xprt->sc_xprt; 699 700 listen_id = rdma_create_id(rdma_listen_handler, cma_xprt, RDMA_PS_TCP, 701 IB_QPT_RC); 702 if (IS_ERR(listen_id)) { 703 ret = PTR_ERR(listen_id); 704 dprintk("svcrdma: rdma_create_id failed = %d\n", ret); 705 goto err0; 706 } 707 708 ret = rdma_bind_addr(listen_id, sa); 709 if (ret) { 710 dprintk("svcrdma: rdma_bind_addr failed = %d\n", ret); 711 goto err1; 712 } 713 cma_xprt->sc_cm_id = listen_id; 714 715 ret = rdma_listen(listen_id, RPCRDMA_LISTEN_BACKLOG); 716 if (ret) { 717 dprintk("svcrdma: rdma_listen failed = %d\n", ret); 718 goto err1; 719 } 720 721 /* 722 * We need to use the address from the cm_id in case the 723 * caller specified 0 for the port number. 724 */ 725 sa = (struct sockaddr *)&cma_xprt->sc_cm_id->route.addr.src_addr; 726 svc_xprt_set_local(&cma_xprt->sc_xprt, sa, salen); 727 728 return &cma_xprt->sc_xprt; 729 730 err1: 731 rdma_destroy_id(listen_id); 732 err0: 733 kfree(cma_xprt); 734 return ERR_PTR(ret); 735 } 736 737 static struct svc_rdma_fastreg_mr *rdma_alloc_frmr(struct svcxprt_rdma *xprt) 738 { 739 struct ib_mr *mr; 740 struct ib_fast_reg_page_list *pl; 741 struct svc_rdma_fastreg_mr *frmr; 742 743 frmr = kmalloc(sizeof(*frmr), GFP_KERNEL); 744 if (!frmr) 745 goto err; 746 747 mr = ib_alloc_fast_reg_mr(xprt->sc_pd, RPCSVC_MAXPAGES); 748 if (IS_ERR(mr)) 749 goto err_free_frmr; 750 751 pl = ib_alloc_fast_reg_page_list(xprt->sc_cm_id->device, 752 RPCSVC_MAXPAGES); 753 if (IS_ERR(pl)) 754 goto err_free_mr; 755 756 frmr->mr = mr; 757 frmr->page_list = pl; 758 INIT_LIST_HEAD(&frmr->frmr_list); 759 return frmr; 760 761 err_free_mr: 762 ib_dereg_mr(mr); 763 err_free_frmr: 764 kfree(frmr); 765 err: 766 return ERR_PTR(-ENOMEM); 767 } 768 769 static void rdma_dealloc_frmr_q(struct svcxprt_rdma *xprt) 770 { 771 struct svc_rdma_fastreg_mr *frmr; 772 773 while (!list_empty(&xprt->sc_frmr_q)) { 774 frmr = list_entry(xprt->sc_frmr_q.next, 775 struct svc_rdma_fastreg_mr, frmr_list); 776 list_del_init(&frmr->frmr_list); 777 ib_dereg_mr(frmr->mr); 778 ib_free_fast_reg_page_list(frmr->page_list); 779 kfree(frmr); 780 } 781 } 782 783 struct svc_rdma_fastreg_mr *svc_rdma_get_frmr(struct svcxprt_rdma *rdma) 784 { 785 struct svc_rdma_fastreg_mr *frmr = NULL; 786 787 spin_lock_bh(&rdma->sc_frmr_q_lock); 788 if (!list_empty(&rdma->sc_frmr_q)) { 789 frmr = list_entry(rdma->sc_frmr_q.next, 790 struct svc_rdma_fastreg_mr, frmr_list); 791 list_del_init(&frmr->frmr_list); 792 frmr->map_len = 0; 793 frmr->page_list_len = 0; 794 } 795 spin_unlock_bh(&rdma->sc_frmr_q_lock); 796 if (frmr) 797 return frmr; 798 799 return rdma_alloc_frmr(rdma); 800 } 801 802 static void frmr_unmap_dma(struct svcxprt_rdma *xprt, 803 struct svc_rdma_fastreg_mr *frmr) 804 { 805 int page_no; 806 for (page_no = 0; page_no < frmr->page_list_len; page_no++) { 807 dma_addr_t addr = frmr->page_list->page_list[page_no]; 808 if (ib_dma_mapping_error(frmr->mr->device, addr)) 809 continue; 810 atomic_dec(&xprt->sc_dma_used); 811 ib_dma_unmap_page(frmr->mr->device, addr, PAGE_SIZE, 812 frmr->direction); 813 } 814 } 815 816 void svc_rdma_put_frmr(struct svcxprt_rdma *rdma, 817 struct svc_rdma_fastreg_mr *frmr) 818 { 819 if (frmr) { 820 frmr_unmap_dma(rdma, frmr); 821 spin_lock_bh(&rdma->sc_frmr_q_lock); 822 BUG_ON(!list_empty(&frmr->frmr_list)); 823 list_add(&frmr->frmr_list, &rdma->sc_frmr_q); 824 spin_unlock_bh(&rdma->sc_frmr_q_lock); 825 } 826 } 827 828 /* 829 * This is the xpo_recvfrom function for listening endpoints. Its 830 * purpose is to accept incoming connections. The CMA callback handler 831 * has already created a new transport and attached it to the new CMA 832 * ID. 833 * 834 * There is a queue of pending connections hung on the listening 835 * transport. This queue contains the new svc_xprt structure. This 836 * function takes svc_xprt structures off the accept_q and completes 837 * the connection. 838 */ 839 static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) 840 { 841 struct svcxprt_rdma *listen_rdma; 842 struct svcxprt_rdma *newxprt = NULL; 843 struct rdma_conn_param conn_param; 844 struct ib_qp_init_attr qp_attr; 845 struct ib_device_attr devattr; 846 int uninitialized_var(dma_mr_acc); 847 int need_dma_mr; 848 int ret; 849 int i; 850 851 listen_rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); 852 clear_bit(XPT_CONN, &xprt->xpt_flags); 853 /* Get the next entry off the accept list */ 854 spin_lock_bh(&listen_rdma->sc_lock); 855 if (!list_empty(&listen_rdma->sc_accept_q)) { 856 newxprt = list_entry(listen_rdma->sc_accept_q.next, 857 struct svcxprt_rdma, sc_accept_q); 858 list_del_init(&newxprt->sc_accept_q); 859 } 860 if (!list_empty(&listen_rdma->sc_accept_q)) 861 set_bit(XPT_CONN, &listen_rdma->sc_xprt.xpt_flags); 862 spin_unlock_bh(&listen_rdma->sc_lock); 863 if (!newxprt) 864 return NULL; 865 866 dprintk("svcrdma: newxprt from accept queue = %p, cm_id=%p\n", 867 newxprt, newxprt->sc_cm_id); 868 869 ret = ib_query_device(newxprt->sc_cm_id->device, &devattr); 870 if (ret) { 871 dprintk("svcrdma: could not query device attributes on " 872 "device %p, rc=%d\n", newxprt->sc_cm_id->device, ret); 873 goto errout; 874 } 875 876 /* Qualify the transport resource defaults with the 877 * capabilities of this particular device */ 878 newxprt->sc_max_sge = min((size_t)devattr.max_sge, 879 (size_t)RPCSVC_MAXPAGES); 880 newxprt->sc_max_requests = min((size_t)devattr.max_qp_wr, 881 (size_t)svcrdma_max_requests); 882 newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_max_requests; 883 884 /* 885 * Limit ORD based on client limit, local device limit, and 886 * configured svcrdma limit. 887 */ 888 newxprt->sc_ord = min_t(size_t, devattr.max_qp_rd_atom, newxprt->sc_ord); 889 newxprt->sc_ord = min_t(size_t, svcrdma_ord, newxprt->sc_ord); 890 891 newxprt->sc_pd = ib_alloc_pd(newxprt->sc_cm_id->device); 892 if (IS_ERR(newxprt->sc_pd)) { 893 dprintk("svcrdma: error creating PD for connect request\n"); 894 goto errout; 895 } 896 newxprt->sc_sq_cq = ib_create_cq(newxprt->sc_cm_id->device, 897 sq_comp_handler, 898 cq_event_handler, 899 newxprt, 900 newxprt->sc_sq_depth, 901 0); 902 if (IS_ERR(newxprt->sc_sq_cq)) { 903 dprintk("svcrdma: error creating SQ CQ for connect request\n"); 904 goto errout; 905 } 906 newxprt->sc_rq_cq = ib_create_cq(newxprt->sc_cm_id->device, 907 rq_comp_handler, 908 cq_event_handler, 909 newxprt, 910 newxprt->sc_max_requests, 911 0); 912 if (IS_ERR(newxprt->sc_rq_cq)) { 913 dprintk("svcrdma: error creating RQ CQ for connect request\n"); 914 goto errout; 915 } 916 917 memset(&qp_attr, 0, sizeof qp_attr); 918 qp_attr.event_handler = qp_event_handler; 919 qp_attr.qp_context = &newxprt->sc_xprt; 920 qp_attr.cap.max_send_wr = newxprt->sc_sq_depth; 921 qp_attr.cap.max_recv_wr = newxprt->sc_max_requests; 922 qp_attr.cap.max_send_sge = newxprt->sc_max_sge; 923 qp_attr.cap.max_recv_sge = newxprt->sc_max_sge; 924 qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; 925 qp_attr.qp_type = IB_QPT_RC; 926 qp_attr.send_cq = newxprt->sc_sq_cq; 927 qp_attr.recv_cq = newxprt->sc_rq_cq; 928 dprintk("svcrdma: newxprt->sc_cm_id=%p, newxprt->sc_pd=%p\n" 929 " cm_id->device=%p, sc_pd->device=%p\n" 930 " cap.max_send_wr = %d\n" 931 " cap.max_recv_wr = %d\n" 932 " cap.max_send_sge = %d\n" 933 " cap.max_recv_sge = %d\n", 934 newxprt->sc_cm_id, newxprt->sc_pd, 935 newxprt->sc_cm_id->device, newxprt->sc_pd->device, 936 qp_attr.cap.max_send_wr, 937 qp_attr.cap.max_recv_wr, 938 qp_attr.cap.max_send_sge, 939 qp_attr.cap.max_recv_sge); 940 941 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, &qp_attr); 942 if (ret) { 943 /* 944 * XXX: This is a hack. We need a xx_request_qp interface 945 * that will adjust the qp_attr's with a best-effort 946 * number 947 */ 948 qp_attr.cap.max_send_sge -= 2; 949 qp_attr.cap.max_recv_sge -= 2; 950 ret = rdma_create_qp(newxprt->sc_cm_id, newxprt->sc_pd, 951 &qp_attr); 952 if (ret) { 953 dprintk("svcrdma: failed to create QP, ret=%d\n", ret); 954 goto errout; 955 } 956 newxprt->sc_max_sge = qp_attr.cap.max_send_sge; 957 newxprt->sc_max_sge = qp_attr.cap.max_recv_sge; 958 newxprt->sc_sq_depth = qp_attr.cap.max_send_wr; 959 newxprt->sc_max_requests = qp_attr.cap.max_recv_wr; 960 } 961 newxprt->sc_qp = newxprt->sc_cm_id->qp; 962 963 /* 964 * Use the most secure set of MR resources based on the 965 * transport type and available memory management features in 966 * the device. Here's the table implemented below: 967 * 968 * Fast Global DMA Remote WR 969 * Reg LKEY MR Access 970 * Sup'd Sup'd Needed Needed 971 * 972 * IWARP N N Y Y 973 * N Y Y Y 974 * Y N Y N 975 * Y Y N - 976 * 977 * IB N N Y N 978 * N Y N - 979 * Y N Y N 980 * Y Y N - 981 * 982 * NB: iWARP requires remote write access for the data sink 983 * of an RDMA_READ. IB does not. 984 */ 985 if (devattr.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) { 986 newxprt->sc_frmr_pg_list_len = 987 devattr.max_fast_reg_page_list_len; 988 newxprt->sc_dev_caps |= SVCRDMA_DEVCAP_FAST_REG; 989 } 990 991 /* 992 * Determine if a DMA MR is required and if so, what privs are required 993 */ 994 switch (rdma_node_get_transport(newxprt->sc_cm_id->device->node_type)) { 995 case RDMA_TRANSPORT_IWARP: 996 newxprt->sc_dev_caps |= SVCRDMA_DEVCAP_READ_W_INV; 997 if (!(newxprt->sc_dev_caps & SVCRDMA_DEVCAP_FAST_REG)) { 998 need_dma_mr = 1; 999 dma_mr_acc = 1000 (IB_ACCESS_LOCAL_WRITE | 1001 IB_ACCESS_REMOTE_WRITE); 1002 } else if (!(devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)) { 1003 need_dma_mr = 1; 1004 dma_mr_acc = IB_ACCESS_LOCAL_WRITE; 1005 } else 1006 need_dma_mr = 0; 1007 break; 1008 case RDMA_TRANSPORT_IB: 1009 if (!(devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY)) { 1010 need_dma_mr = 1; 1011 dma_mr_acc = IB_ACCESS_LOCAL_WRITE; 1012 } else 1013 need_dma_mr = 0; 1014 break; 1015 default: 1016 goto errout; 1017 } 1018 1019 /* Create the DMA MR if needed, otherwise, use the DMA LKEY */ 1020 if (need_dma_mr) { 1021 /* Register all of physical memory */ 1022 newxprt->sc_phys_mr = 1023 ib_get_dma_mr(newxprt->sc_pd, dma_mr_acc); 1024 if (IS_ERR(newxprt->sc_phys_mr)) { 1025 dprintk("svcrdma: Failed to create DMA MR ret=%d\n", 1026 ret); 1027 goto errout; 1028 } 1029 newxprt->sc_dma_lkey = newxprt->sc_phys_mr->lkey; 1030 } else 1031 newxprt->sc_dma_lkey = 1032 newxprt->sc_cm_id->device->local_dma_lkey; 1033 1034 /* Post receive buffers */ 1035 for (i = 0; i < newxprt->sc_max_requests; i++) { 1036 ret = svc_rdma_post_recv(newxprt); 1037 if (ret) { 1038 dprintk("svcrdma: failure posting receive buffers\n"); 1039 goto errout; 1040 } 1041 } 1042 1043 /* Swap out the handler */ 1044 newxprt->sc_cm_id->event_handler = rdma_cma_handler; 1045 1046 /* 1047 * Arm the CQs for the SQ and RQ before accepting so we can't 1048 * miss the first message 1049 */ 1050 ib_req_notify_cq(newxprt->sc_sq_cq, IB_CQ_NEXT_COMP); 1051 ib_req_notify_cq(newxprt->sc_rq_cq, IB_CQ_NEXT_COMP); 1052 1053 /* Accept Connection */ 1054 set_bit(RDMAXPRT_CONN_PENDING, &newxprt->sc_flags); 1055 memset(&conn_param, 0, sizeof conn_param); 1056 conn_param.responder_resources = 0; 1057 conn_param.initiator_depth = newxprt->sc_ord; 1058 ret = rdma_accept(newxprt->sc_cm_id, &conn_param); 1059 if (ret) { 1060 dprintk("svcrdma: failed to accept new connection, ret=%d\n", 1061 ret); 1062 goto errout; 1063 } 1064 1065 dprintk("svcrdma: new connection %p accepted with the following " 1066 "attributes:\n" 1067 " local_ip : %pI4\n" 1068 " local_port : %d\n" 1069 " remote_ip : %pI4\n" 1070 " remote_port : %d\n" 1071 " max_sge : %d\n" 1072 " sq_depth : %d\n" 1073 " max_requests : %d\n" 1074 " ord : %d\n", 1075 newxprt, 1076 &((struct sockaddr_in *)&newxprt->sc_cm_id-> 1077 route.addr.src_addr)->sin_addr.s_addr, 1078 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id-> 1079 route.addr.src_addr)->sin_port), 1080 &((struct sockaddr_in *)&newxprt->sc_cm_id-> 1081 route.addr.dst_addr)->sin_addr.s_addr, 1082 ntohs(((struct sockaddr_in *)&newxprt->sc_cm_id-> 1083 route.addr.dst_addr)->sin_port), 1084 newxprt->sc_max_sge, 1085 newxprt->sc_sq_depth, 1086 newxprt->sc_max_requests, 1087 newxprt->sc_ord); 1088 1089 return &newxprt->sc_xprt; 1090 1091 errout: 1092 dprintk("svcrdma: failure accepting new connection rc=%d.\n", ret); 1093 /* Take a reference in case the DTO handler runs */ 1094 svc_xprt_get(&newxprt->sc_xprt); 1095 if (newxprt->sc_qp && !IS_ERR(newxprt->sc_qp)) 1096 ib_destroy_qp(newxprt->sc_qp); 1097 rdma_destroy_id(newxprt->sc_cm_id); 1098 /* This call to put will destroy the transport */ 1099 svc_xprt_put(&newxprt->sc_xprt); 1100 return NULL; 1101 } 1102 1103 static void svc_rdma_release_rqst(struct svc_rqst *rqstp) 1104 { 1105 } 1106 1107 /* 1108 * When connected, an svc_xprt has at least two references: 1109 * 1110 * - A reference held by the cm_id between the ESTABLISHED and 1111 * DISCONNECTED events. If the remote peer disconnected first, this 1112 * reference could be gone. 1113 * 1114 * - A reference held by the svc_recv code that called this function 1115 * as part of close processing. 1116 * 1117 * At a minimum one references should still be held. 1118 */ 1119 static void svc_rdma_detach(struct svc_xprt *xprt) 1120 { 1121 struct svcxprt_rdma *rdma = 1122 container_of(xprt, struct svcxprt_rdma, sc_xprt); 1123 dprintk("svc: svc_rdma_detach(%p)\n", xprt); 1124 1125 /* Disconnect and flush posted WQE */ 1126 rdma_disconnect(rdma->sc_cm_id); 1127 } 1128 1129 static void __svc_rdma_free(struct work_struct *work) 1130 { 1131 struct svcxprt_rdma *rdma = 1132 container_of(work, struct svcxprt_rdma, sc_work); 1133 dprintk("svcrdma: svc_rdma_free(%p)\n", rdma); 1134 1135 /* We should only be called from kref_put */ 1136 BUG_ON(atomic_read(&rdma->sc_xprt.xpt_ref.refcount) != 0); 1137 1138 /* 1139 * Destroy queued, but not processed read completions. Note 1140 * that this cleanup has to be done before destroying the 1141 * cm_id because the device ptr is needed to unmap the dma in 1142 * svc_rdma_put_context. 1143 */ 1144 while (!list_empty(&rdma->sc_read_complete_q)) { 1145 struct svc_rdma_op_ctxt *ctxt; 1146 ctxt = list_entry(rdma->sc_read_complete_q.next, 1147 struct svc_rdma_op_ctxt, 1148 dto_q); 1149 list_del_init(&ctxt->dto_q); 1150 svc_rdma_put_context(ctxt, 1); 1151 } 1152 1153 /* Destroy queued, but not processed recv completions */ 1154 while (!list_empty(&rdma->sc_rq_dto_q)) { 1155 struct svc_rdma_op_ctxt *ctxt; 1156 ctxt = list_entry(rdma->sc_rq_dto_q.next, 1157 struct svc_rdma_op_ctxt, 1158 dto_q); 1159 list_del_init(&ctxt->dto_q); 1160 svc_rdma_put_context(ctxt, 1); 1161 } 1162 1163 /* Warn if we leaked a resource or under-referenced */ 1164 WARN_ON(atomic_read(&rdma->sc_ctxt_used) != 0); 1165 WARN_ON(atomic_read(&rdma->sc_dma_used) != 0); 1166 1167 /* De-allocate fastreg mr */ 1168 rdma_dealloc_frmr_q(rdma); 1169 1170 /* Destroy the QP if present (not a listener) */ 1171 if (rdma->sc_qp && !IS_ERR(rdma->sc_qp)) 1172 ib_destroy_qp(rdma->sc_qp); 1173 1174 if (rdma->sc_sq_cq && !IS_ERR(rdma->sc_sq_cq)) 1175 ib_destroy_cq(rdma->sc_sq_cq); 1176 1177 if (rdma->sc_rq_cq && !IS_ERR(rdma->sc_rq_cq)) 1178 ib_destroy_cq(rdma->sc_rq_cq); 1179 1180 if (rdma->sc_phys_mr && !IS_ERR(rdma->sc_phys_mr)) 1181 ib_dereg_mr(rdma->sc_phys_mr); 1182 1183 if (rdma->sc_pd && !IS_ERR(rdma->sc_pd)) 1184 ib_dealloc_pd(rdma->sc_pd); 1185 1186 /* Destroy the CM ID */ 1187 rdma_destroy_id(rdma->sc_cm_id); 1188 1189 kfree(rdma); 1190 } 1191 1192 static void svc_rdma_free(struct svc_xprt *xprt) 1193 { 1194 struct svcxprt_rdma *rdma = 1195 container_of(xprt, struct svcxprt_rdma, sc_xprt); 1196 INIT_WORK(&rdma->sc_work, __svc_rdma_free); 1197 queue_work(svc_rdma_wq, &rdma->sc_work); 1198 } 1199 1200 static int svc_rdma_has_wspace(struct svc_xprt *xprt) 1201 { 1202 struct svcxprt_rdma *rdma = 1203 container_of(xprt, struct svcxprt_rdma, sc_xprt); 1204 1205 /* 1206 * If there are fewer SQ WR available than required to send a 1207 * simple response, return false. 1208 */ 1209 if ((rdma->sc_sq_depth - atomic_read(&rdma->sc_sq_count) < 3)) 1210 return 0; 1211 1212 /* 1213 * ...or there are already waiters on the SQ, 1214 * return false. 1215 */ 1216 if (waitqueue_active(&rdma->sc_send_wait)) 1217 return 0; 1218 1219 /* Otherwise return true. */ 1220 return 1; 1221 } 1222 1223 /* 1224 * Attempt to register the kvec representing the RPC memory with the 1225 * device. 1226 * 1227 * Returns: 1228 * NULL : The device does not support fastreg or there were no more 1229 * fastreg mr. 1230 * frmr : The kvec register request was successfully posted. 1231 * <0 : An error was encountered attempting to register the kvec. 1232 */ 1233 int svc_rdma_fastreg(struct svcxprt_rdma *xprt, 1234 struct svc_rdma_fastreg_mr *frmr) 1235 { 1236 struct ib_send_wr fastreg_wr; 1237 u8 key; 1238 1239 /* Bump the key */ 1240 key = (u8)(frmr->mr->lkey & 0x000000FF); 1241 ib_update_fast_reg_key(frmr->mr, ++key); 1242 1243 /* Prepare FASTREG WR */ 1244 memset(&fastreg_wr, 0, sizeof fastreg_wr); 1245 fastreg_wr.opcode = IB_WR_FAST_REG_MR; 1246 fastreg_wr.send_flags = IB_SEND_SIGNALED; 1247 fastreg_wr.wr.fast_reg.iova_start = (unsigned long)frmr->kva; 1248 fastreg_wr.wr.fast_reg.page_list = frmr->page_list; 1249 fastreg_wr.wr.fast_reg.page_list_len = frmr->page_list_len; 1250 fastreg_wr.wr.fast_reg.page_shift = PAGE_SHIFT; 1251 fastreg_wr.wr.fast_reg.length = frmr->map_len; 1252 fastreg_wr.wr.fast_reg.access_flags = frmr->access_flags; 1253 fastreg_wr.wr.fast_reg.rkey = frmr->mr->lkey; 1254 return svc_rdma_send(xprt, &fastreg_wr); 1255 } 1256 1257 int svc_rdma_send(struct svcxprt_rdma *xprt, struct ib_send_wr *wr) 1258 { 1259 struct ib_send_wr *bad_wr, *n_wr; 1260 int wr_count; 1261 int i; 1262 int ret; 1263 1264 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags)) 1265 return -ENOTCONN; 1266 1267 BUG_ON(wr->send_flags != IB_SEND_SIGNALED); 1268 wr_count = 1; 1269 for (n_wr = wr->next; n_wr; n_wr = n_wr->next) 1270 wr_count++; 1271 1272 /* If the SQ is full, wait until an SQ entry is available */ 1273 while (1) { 1274 spin_lock_bh(&xprt->sc_lock); 1275 if (xprt->sc_sq_depth < atomic_read(&xprt->sc_sq_count) + wr_count) { 1276 spin_unlock_bh(&xprt->sc_lock); 1277 atomic_inc(&rdma_stat_sq_starve); 1278 1279 /* See if we can opportunistically reap SQ WR to make room */ 1280 sq_cq_reap(xprt); 1281 1282 /* Wait until SQ WR available if SQ still full */ 1283 wait_event(xprt->sc_send_wait, 1284 atomic_read(&xprt->sc_sq_count) < 1285 xprt->sc_sq_depth); 1286 if (test_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags)) 1287 return -ENOTCONN; 1288 continue; 1289 } 1290 /* Take a transport ref for each WR posted */ 1291 for (i = 0; i < wr_count; i++) 1292 svc_xprt_get(&xprt->sc_xprt); 1293 1294 /* Bump used SQ WR count and post */ 1295 atomic_add(wr_count, &xprt->sc_sq_count); 1296 ret = ib_post_send(xprt->sc_qp, wr, &bad_wr); 1297 if (ret) { 1298 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 1299 atomic_sub(wr_count, &xprt->sc_sq_count); 1300 for (i = 0; i < wr_count; i ++) 1301 svc_xprt_put(&xprt->sc_xprt); 1302 dprintk("svcrdma: failed to post SQ WR rc=%d, " 1303 "sc_sq_count=%d, sc_sq_depth=%d\n", 1304 ret, atomic_read(&xprt->sc_sq_count), 1305 xprt->sc_sq_depth); 1306 } 1307 spin_unlock_bh(&xprt->sc_lock); 1308 if (ret) 1309 wake_up(&xprt->sc_send_wait); 1310 break; 1311 } 1312 return ret; 1313 } 1314 1315 void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp, 1316 enum rpcrdma_errcode err) 1317 { 1318 struct ib_send_wr err_wr; 1319 struct page *p; 1320 struct svc_rdma_op_ctxt *ctxt; 1321 u32 *va; 1322 int length; 1323 int ret; 1324 1325 p = svc_rdma_get_page(); 1326 va = page_address(p); 1327 1328 /* XDR encode error */ 1329 length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va); 1330 1331 ctxt = svc_rdma_get_context(xprt); 1332 ctxt->direction = DMA_FROM_DEVICE; 1333 ctxt->count = 1; 1334 ctxt->pages[0] = p; 1335 1336 /* Prepare SGE for local address */ 1337 ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device, 1338 p, 0, length, DMA_FROM_DEVICE); 1339 if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) { 1340 put_page(p); 1341 svc_rdma_put_context(ctxt, 1); 1342 return; 1343 } 1344 atomic_inc(&xprt->sc_dma_used); 1345 ctxt->sge[0].lkey = xprt->sc_dma_lkey; 1346 ctxt->sge[0].length = length; 1347 1348 /* Prepare SEND WR */ 1349 memset(&err_wr, 0, sizeof err_wr); 1350 ctxt->wr_op = IB_WR_SEND; 1351 err_wr.wr_id = (unsigned long)ctxt; 1352 err_wr.sg_list = ctxt->sge; 1353 err_wr.num_sge = 1; 1354 err_wr.opcode = IB_WR_SEND; 1355 err_wr.send_flags = IB_SEND_SIGNALED; 1356 1357 /* Post It */ 1358 ret = svc_rdma_send(xprt, &err_wr); 1359 if (ret) { 1360 dprintk("svcrdma: Error %d posting send for protocol error\n", 1361 ret); 1362 svc_rdma_unmap_dma(ctxt); 1363 svc_rdma_put_context(ctxt, 1); 1364 } 1365 } 1366