1 /* 2 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved. 3 * Copyright (c) 2005, 2006 Cisco Systems. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 */ 33 #include <linux/kernel.h> 34 #include <linux/module.h> 35 #include <linux/delay.h> 36 #include <linux/version.h> 37 38 #include "iscsi_iser.h" 39 40 #define ISCSI_ISER_MAX_CONN 8 41 #define ISER_MAX_CQ_LEN ((ISER_QP_MAX_RECV_DTOS + \ 42 ISER_QP_MAX_REQ_DTOS) * \ 43 ISCSI_ISER_MAX_CONN) 44 45 static void iser_cq_tasklet_fn(unsigned long data); 46 static void iser_cq_callback(struct ib_cq *cq, void *cq_context); 47 48 static void iser_cq_event_callback(struct ib_event *cause, void *context) 49 { 50 iser_err("got cq event %d \n", cause->event); 51 } 52 53 static void iser_qp_event_callback(struct ib_event *cause, void *context) 54 { 55 iser_err("got qp event %d\n",cause->event); 56 } 57 58 /** 59 * iser_create_device_ib_res - creates Protection Domain (PD), Completion 60 * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with 61 * the adapator. 62 * 63 * returns 0 on success, -1 on failure 64 */ 65 static int iser_create_device_ib_res(struct iser_device *device) 66 { 67 device->pd = ib_alloc_pd(device->ib_device); 68 if (IS_ERR(device->pd)) 69 goto pd_err; 70 71 device->cq = ib_create_cq(device->ib_device, 72 iser_cq_callback, 73 iser_cq_event_callback, 74 (void *)device, 75 ISER_MAX_CQ_LEN, 0); 76 if (IS_ERR(device->cq)) 77 goto cq_err; 78 79 if (ib_req_notify_cq(device->cq, IB_CQ_NEXT_COMP)) 80 goto cq_arm_err; 81 82 tasklet_init(&device->cq_tasklet, 83 iser_cq_tasklet_fn, 84 (unsigned long)device); 85 86 device->mr = ib_get_dma_mr(device->pd, IB_ACCESS_LOCAL_WRITE | 87 IB_ACCESS_REMOTE_WRITE | 88 IB_ACCESS_REMOTE_READ); 89 if (IS_ERR(device->mr)) 90 goto dma_mr_err; 91 92 return 0; 93 94 dma_mr_err: 95 tasklet_kill(&device->cq_tasklet); 96 cq_arm_err: 97 ib_destroy_cq(device->cq); 98 cq_err: 99 ib_dealloc_pd(device->pd); 100 pd_err: 101 iser_err("failed to allocate an IB resource\n"); 102 return -1; 103 } 104 105 /** 106 * iser_free_device_ib_res - destroy/dealloc/dereg the DMA MR, 107 * CQ and PD created with the device associated with the adapator. 108 */ 109 static void iser_free_device_ib_res(struct iser_device *device) 110 { 111 BUG_ON(device->mr == NULL); 112 113 tasklet_kill(&device->cq_tasklet); 114 115 (void)ib_dereg_mr(device->mr); 116 (void)ib_destroy_cq(device->cq); 117 (void)ib_dealloc_pd(device->pd); 118 119 device->mr = NULL; 120 device->cq = NULL; 121 device->pd = NULL; 122 } 123 124 /** 125 * iser_create_ib_conn_res - Creates FMR pool and Queue-Pair (QP) 126 * 127 * returns 0 on success, -1 on failure 128 */ 129 static int iser_create_ib_conn_res(struct iser_conn *ib_conn) 130 { 131 struct iser_device *device; 132 struct ib_qp_init_attr init_attr; 133 int ret; 134 struct ib_fmr_pool_param params; 135 136 BUG_ON(ib_conn->device == NULL); 137 138 device = ib_conn->device; 139 140 ib_conn->page_vec = kmalloc(sizeof(struct iser_page_vec) + 141 (sizeof(u64) * (ISCSI_ISER_SG_TABLESIZE +1)), 142 GFP_KERNEL); 143 if (!ib_conn->page_vec) { 144 ret = -ENOMEM; 145 goto alloc_err; 146 } 147 ib_conn->page_vec->pages = (u64 *) (ib_conn->page_vec + 1); 148 149 params.page_shift = SHIFT_4K; 150 /* when the first/last SG element are not start/end * 151 * page aligned, the map whould be of N+1 pages */ 152 params.max_pages_per_fmr = ISCSI_ISER_SG_TABLESIZE + 1; 153 /* make the pool size twice the max number of SCSI commands * 154 * the ML is expected to queue, watermark for unmap at 50% */ 155 params.pool_size = ISCSI_DEF_XMIT_CMDS_MAX * 2; 156 params.dirty_watermark = ISCSI_DEF_XMIT_CMDS_MAX; 157 params.cache = 0; 158 params.flush_function = NULL; 159 params.access = (IB_ACCESS_LOCAL_WRITE | 160 IB_ACCESS_REMOTE_WRITE | 161 IB_ACCESS_REMOTE_READ); 162 163 ib_conn->fmr_pool = ib_create_fmr_pool(device->pd, ¶ms); 164 if (IS_ERR(ib_conn->fmr_pool)) { 165 ret = PTR_ERR(ib_conn->fmr_pool); 166 goto fmr_pool_err; 167 } 168 169 memset(&init_attr, 0, sizeof init_attr); 170 171 init_attr.event_handler = iser_qp_event_callback; 172 init_attr.qp_context = (void *)ib_conn; 173 init_attr.send_cq = device->cq; 174 init_attr.recv_cq = device->cq; 175 init_attr.cap.max_send_wr = ISER_QP_MAX_REQ_DTOS; 176 init_attr.cap.max_recv_wr = ISER_QP_MAX_RECV_DTOS; 177 init_attr.cap.max_send_sge = MAX_REGD_BUF_VECTOR_LEN; 178 init_attr.cap.max_recv_sge = 2; 179 init_attr.sq_sig_type = IB_SIGNAL_REQ_WR; 180 init_attr.qp_type = IB_QPT_RC; 181 182 ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr); 183 if (ret) 184 goto qp_err; 185 186 ib_conn->qp = ib_conn->cma_id->qp; 187 iser_err("setting conn %p cma_id %p: fmr_pool %p qp %p\n", 188 ib_conn, ib_conn->cma_id, 189 ib_conn->fmr_pool, ib_conn->cma_id->qp); 190 return ret; 191 192 qp_err: 193 (void)ib_destroy_fmr_pool(ib_conn->fmr_pool); 194 fmr_pool_err: 195 kfree(ib_conn->page_vec); 196 alloc_err: 197 iser_err("unable to alloc mem or create resource, err %d\n", ret); 198 return ret; 199 } 200 201 /** 202 * releases the FMR pool, QP and CMA ID objects, returns 0 on success, 203 * -1 on failure 204 */ 205 static int iser_free_ib_conn_res(struct iser_conn *ib_conn) 206 { 207 BUG_ON(ib_conn == NULL); 208 209 iser_err("freeing conn %p cma_id %p fmr pool %p qp %p\n", 210 ib_conn, ib_conn->cma_id, 211 ib_conn->fmr_pool, ib_conn->qp); 212 213 /* qp is created only once both addr & route are resolved */ 214 if (ib_conn->fmr_pool != NULL) 215 ib_destroy_fmr_pool(ib_conn->fmr_pool); 216 217 if (ib_conn->qp != NULL) 218 rdma_destroy_qp(ib_conn->cma_id); 219 220 if (ib_conn->cma_id != NULL) 221 rdma_destroy_id(ib_conn->cma_id); 222 223 ib_conn->fmr_pool = NULL; 224 ib_conn->qp = NULL; 225 ib_conn->cma_id = NULL; 226 kfree(ib_conn->page_vec); 227 228 return 0; 229 } 230 231 /** 232 * based on the resolved device node GUID see if there already allocated 233 * device for this device. If there's no such, create one. 234 */ 235 static 236 struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id) 237 { 238 struct iser_device *device; 239 240 mutex_lock(&ig.device_list_mutex); 241 242 list_for_each_entry(device, &ig.device_list, ig_list) 243 /* find if there's a match using the node GUID */ 244 if (device->ib_device->node_guid == cma_id->device->node_guid) 245 goto inc_refcnt; 246 247 device = kzalloc(sizeof *device, GFP_KERNEL); 248 if (device == NULL) 249 goto out; 250 251 /* assign this device to the device */ 252 device->ib_device = cma_id->device; 253 /* init the device and link it into ig device list */ 254 if (iser_create_device_ib_res(device)) { 255 kfree(device); 256 device = NULL; 257 goto out; 258 } 259 list_add(&device->ig_list, &ig.device_list); 260 261 inc_refcnt: 262 device->refcount++; 263 out: 264 mutex_unlock(&ig.device_list_mutex); 265 return device; 266 } 267 268 /* if there's no demand for this device, release it */ 269 static void iser_device_try_release(struct iser_device *device) 270 { 271 mutex_lock(&ig.device_list_mutex); 272 device->refcount--; 273 iser_err("device %p refcount %d\n",device,device->refcount); 274 if (!device->refcount) { 275 iser_free_device_ib_res(device); 276 list_del(&device->ig_list); 277 kfree(device); 278 } 279 mutex_unlock(&ig.device_list_mutex); 280 } 281 282 int iser_conn_state_comp(struct iser_conn *ib_conn, 283 enum iser_ib_conn_state comp) 284 { 285 int ret; 286 287 spin_lock_bh(&ib_conn->lock); 288 ret = (ib_conn->state == comp); 289 spin_unlock_bh(&ib_conn->lock); 290 return ret; 291 } 292 293 static int iser_conn_state_comp_exch(struct iser_conn *ib_conn, 294 enum iser_ib_conn_state comp, 295 enum iser_ib_conn_state exch) 296 { 297 int ret; 298 299 spin_lock_bh(&ib_conn->lock); 300 if ((ret = (ib_conn->state == comp))) 301 ib_conn->state = exch; 302 spin_unlock_bh(&ib_conn->lock); 303 return ret; 304 } 305 306 /** 307 * Frees all conn objects and deallocs conn descriptor 308 */ 309 static void iser_conn_release(struct iser_conn *ib_conn) 310 { 311 struct iser_device *device = ib_conn->device; 312 313 BUG_ON(ib_conn->state != ISER_CONN_DOWN); 314 315 mutex_lock(&ig.connlist_mutex); 316 list_del(&ib_conn->conn_list); 317 mutex_unlock(&ig.connlist_mutex); 318 319 iser_free_ib_conn_res(ib_conn); 320 ib_conn->device = NULL; 321 /* on EVENT_ADDR_ERROR there's no device yet for this conn */ 322 if (device != NULL) 323 iser_device_try_release(device); 324 if (ib_conn->iser_conn) 325 ib_conn->iser_conn->ib_conn = NULL; 326 iscsi_destroy_endpoint(ib_conn->ep); 327 } 328 329 void iser_conn_get(struct iser_conn *ib_conn) 330 { 331 atomic_inc(&ib_conn->refcount); 332 } 333 334 void iser_conn_put(struct iser_conn *ib_conn) 335 { 336 if (atomic_dec_and_test(&ib_conn->refcount)) 337 iser_conn_release(ib_conn); 338 } 339 340 /** 341 * triggers start of the disconnect procedures and wait for them to be done 342 */ 343 void iser_conn_terminate(struct iser_conn *ib_conn) 344 { 345 int err = 0; 346 347 /* change the ib conn state only if the conn is UP, however always call 348 * rdma_disconnect since this is the only way to cause the CMA to change 349 * the QP state to ERROR 350 */ 351 352 iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, ISER_CONN_TERMINATING); 353 err = rdma_disconnect(ib_conn->cma_id); 354 if (err) 355 iser_err("Failed to disconnect, conn: 0x%p err %d\n", 356 ib_conn,err); 357 358 wait_event_interruptible(ib_conn->wait, 359 ib_conn->state == ISER_CONN_DOWN); 360 361 iser_conn_put(ib_conn); 362 } 363 364 static void iser_connect_error(struct rdma_cm_id *cma_id) 365 { 366 struct iser_conn *ib_conn; 367 ib_conn = (struct iser_conn *)cma_id->context; 368 369 ib_conn->state = ISER_CONN_DOWN; 370 wake_up_interruptible(&ib_conn->wait); 371 } 372 373 static void iser_addr_handler(struct rdma_cm_id *cma_id) 374 { 375 struct iser_device *device; 376 struct iser_conn *ib_conn; 377 int ret; 378 379 device = iser_device_find_by_ib_device(cma_id); 380 if (!device) { 381 iser_err("device lookup/creation failed\n"); 382 iser_connect_error(cma_id); 383 return; 384 } 385 386 ib_conn = (struct iser_conn *)cma_id->context; 387 ib_conn->device = device; 388 389 ret = rdma_resolve_route(cma_id, 1000); 390 if (ret) { 391 iser_err("resolve route failed: %d\n", ret); 392 iser_connect_error(cma_id); 393 } 394 } 395 396 static void iser_route_handler(struct rdma_cm_id *cma_id) 397 { 398 struct rdma_conn_param conn_param; 399 int ret; 400 401 ret = iser_create_ib_conn_res((struct iser_conn *)cma_id->context); 402 if (ret) 403 goto failure; 404 405 iser_dbg("path.mtu is %d setting it to %d\n", 406 cma_id->route.path_rec->mtu, IB_MTU_1024); 407 408 /* we must set the MTU to 1024 as this is what the target is assuming */ 409 if (cma_id->route.path_rec->mtu > IB_MTU_1024) 410 cma_id->route.path_rec->mtu = IB_MTU_1024; 411 412 memset(&conn_param, 0, sizeof conn_param); 413 conn_param.responder_resources = 4; 414 conn_param.initiator_depth = 1; 415 conn_param.retry_count = 7; 416 conn_param.rnr_retry_count = 6; 417 418 ret = rdma_connect(cma_id, &conn_param); 419 if (ret) { 420 iser_err("failure connecting: %d\n", ret); 421 goto failure; 422 } 423 424 return; 425 failure: 426 iser_connect_error(cma_id); 427 } 428 429 static void iser_connected_handler(struct rdma_cm_id *cma_id) 430 { 431 struct iser_conn *ib_conn; 432 433 ib_conn = (struct iser_conn *)cma_id->context; 434 ib_conn->state = ISER_CONN_UP; 435 wake_up_interruptible(&ib_conn->wait); 436 } 437 438 static void iser_disconnected_handler(struct rdma_cm_id *cma_id) 439 { 440 struct iser_conn *ib_conn; 441 442 ib_conn = (struct iser_conn *)cma_id->context; 443 ib_conn->disc_evt_flag = 1; 444 445 /* getting here when the state is UP means that the conn is being * 446 * terminated asynchronously from the iSCSI layer's perspective. */ 447 if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, 448 ISER_CONN_TERMINATING)) 449 iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn, 450 ISCSI_ERR_CONN_FAILED); 451 452 /* Complete the termination process if no posts are pending */ 453 if ((atomic_read(&ib_conn->post_recv_buf_count) == 0) && 454 (atomic_read(&ib_conn->post_send_buf_count) == 0)) { 455 ib_conn->state = ISER_CONN_DOWN; 456 wake_up_interruptible(&ib_conn->wait); 457 } 458 } 459 460 static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event) 461 { 462 int ret = 0; 463 464 iser_err("event %d conn %p id %p\n",event->event,cma_id->context,cma_id); 465 466 switch (event->event) { 467 case RDMA_CM_EVENT_ADDR_RESOLVED: 468 iser_addr_handler(cma_id); 469 break; 470 case RDMA_CM_EVENT_ROUTE_RESOLVED: 471 iser_route_handler(cma_id); 472 break; 473 case RDMA_CM_EVENT_ESTABLISHED: 474 iser_connected_handler(cma_id); 475 break; 476 case RDMA_CM_EVENT_ADDR_ERROR: 477 case RDMA_CM_EVENT_ROUTE_ERROR: 478 case RDMA_CM_EVENT_CONNECT_ERROR: 479 case RDMA_CM_EVENT_UNREACHABLE: 480 case RDMA_CM_EVENT_REJECTED: 481 iser_err("event: %d, error: %d\n", event->event, event->status); 482 iser_connect_error(cma_id); 483 break; 484 case RDMA_CM_EVENT_DISCONNECTED: 485 case RDMA_CM_EVENT_DEVICE_REMOVAL: 486 case RDMA_CM_EVENT_ADDR_CHANGE: 487 iser_disconnected_handler(cma_id); 488 break; 489 default: 490 iser_err("Unexpected RDMA CM event (%d)\n", event->event); 491 break; 492 } 493 return ret; 494 } 495 496 void iser_conn_init(struct iser_conn *ib_conn) 497 { 498 ib_conn->state = ISER_CONN_INIT; 499 init_waitqueue_head(&ib_conn->wait); 500 atomic_set(&ib_conn->post_recv_buf_count, 0); 501 atomic_set(&ib_conn->post_send_buf_count, 0); 502 atomic_set(&ib_conn->refcount, 1); 503 INIT_LIST_HEAD(&ib_conn->conn_list); 504 spin_lock_init(&ib_conn->lock); 505 } 506 507 /** 508 * starts the process of connecting to the target 509 * sleeps untill the connection is established or rejected 510 */ 511 int iser_connect(struct iser_conn *ib_conn, 512 struct sockaddr_in *src_addr, 513 struct sockaddr_in *dst_addr, 514 int non_blocking) 515 { 516 struct sockaddr *src, *dst; 517 int err = 0; 518 519 sprintf(ib_conn->name,"%d.%d.%d.%d:%d", 520 NIPQUAD(dst_addr->sin_addr.s_addr), dst_addr->sin_port); 521 522 /* the device is known only --after-- address resolution */ 523 ib_conn->device = NULL; 524 525 iser_err("connecting to: %d.%d.%d.%d, port 0x%x\n", 526 NIPQUAD(dst_addr->sin_addr), dst_addr->sin_port); 527 528 ib_conn->state = ISER_CONN_PENDING; 529 530 ib_conn->cma_id = rdma_create_id(iser_cma_handler, 531 (void *)ib_conn, 532 RDMA_PS_TCP); 533 if (IS_ERR(ib_conn->cma_id)) { 534 err = PTR_ERR(ib_conn->cma_id); 535 iser_err("rdma_create_id failed: %d\n", err); 536 goto id_failure; 537 } 538 539 src = (struct sockaddr *)src_addr; 540 dst = (struct sockaddr *)dst_addr; 541 err = rdma_resolve_addr(ib_conn->cma_id, src, dst, 1000); 542 if (err) { 543 iser_err("rdma_resolve_addr failed: %d\n", err); 544 goto addr_failure; 545 } 546 547 if (!non_blocking) { 548 wait_event_interruptible(ib_conn->wait, 549 (ib_conn->state != ISER_CONN_PENDING)); 550 551 if (ib_conn->state != ISER_CONN_UP) { 552 err = -EIO; 553 goto connect_failure; 554 } 555 } 556 557 mutex_lock(&ig.connlist_mutex); 558 list_add(&ib_conn->conn_list, &ig.connlist); 559 mutex_unlock(&ig.connlist_mutex); 560 return 0; 561 562 id_failure: 563 ib_conn->cma_id = NULL; 564 addr_failure: 565 ib_conn->state = ISER_CONN_DOWN; 566 connect_failure: 567 iser_conn_release(ib_conn); 568 return err; 569 } 570 571 /** 572 * iser_reg_page_vec - Register physical memory 573 * 574 * returns: 0 on success, errno code on failure 575 */ 576 int iser_reg_page_vec(struct iser_conn *ib_conn, 577 struct iser_page_vec *page_vec, 578 struct iser_mem_reg *mem_reg) 579 { 580 struct ib_pool_fmr *mem; 581 u64 io_addr; 582 u64 *page_list; 583 int status; 584 585 page_list = page_vec->pages; 586 io_addr = page_list[0]; 587 588 mem = ib_fmr_pool_map_phys(ib_conn->fmr_pool, 589 page_list, 590 page_vec->length, 591 io_addr); 592 593 if (IS_ERR(mem)) { 594 status = (int)PTR_ERR(mem); 595 iser_err("ib_fmr_pool_map_phys failed: %d\n", status); 596 return status; 597 } 598 599 mem_reg->lkey = mem->fmr->lkey; 600 mem_reg->rkey = mem->fmr->rkey; 601 mem_reg->len = page_vec->length * SIZE_4K; 602 mem_reg->va = io_addr; 603 mem_reg->is_fmr = 1; 604 mem_reg->mem_h = (void *)mem; 605 606 mem_reg->va += page_vec->offset; 607 mem_reg->len = page_vec->data_size; 608 609 iser_dbg("PHYSICAL Mem.register, [PHYS p_array: 0x%p, sz: %d, " 610 "entry[0]: (0x%08lx,%ld)] -> " 611 "[lkey: 0x%08X mem_h: 0x%p va: 0x%08lX sz: %ld]\n", 612 page_vec, page_vec->length, 613 (unsigned long)page_vec->pages[0], 614 (unsigned long)page_vec->data_size, 615 (unsigned int)mem_reg->lkey, mem_reg->mem_h, 616 (unsigned long)mem_reg->va, (unsigned long)mem_reg->len); 617 return 0; 618 } 619 620 /** 621 * Unregister (previosuly registered) memory. 622 */ 623 void iser_unreg_mem(struct iser_mem_reg *reg) 624 { 625 int ret; 626 627 iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n",reg->mem_h); 628 629 ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h); 630 if (ret) 631 iser_err("ib_fmr_pool_unmap failed %d\n", ret); 632 633 reg->mem_h = NULL; 634 } 635 636 /** 637 * iser_dto_to_iov - builds IOV from a dto descriptor 638 */ 639 static void iser_dto_to_iov(struct iser_dto *dto, struct ib_sge *iov, int iov_len) 640 { 641 int i; 642 struct ib_sge *sge; 643 struct iser_regd_buf *regd_buf; 644 645 if (dto->regd_vector_len > iov_len) { 646 iser_err("iov size %d too small for posting dto of len %d\n", 647 iov_len, dto->regd_vector_len); 648 BUG(); 649 } 650 651 for (i = 0; i < dto->regd_vector_len; i++) { 652 sge = &iov[i]; 653 regd_buf = dto->regd[i]; 654 655 sge->addr = regd_buf->reg.va; 656 sge->length = regd_buf->reg.len; 657 sge->lkey = regd_buf->reg.lkey; 658 659 if (dto->used_sz[i] > 0) /* Adjust size */ 660 sge->length = dto->used_sz[i]; 661 662 /* offset and length should not exceed the regd buf length */ 663 if (sge->length + dto->offset[i] > regd_buf->reg.len) { 664 iser_err("Used len:%ld + offset:%d, exceed reg.buf.len:" 665 "%ld in dto:0x%p [%d], va:0x%08lX\n", 666 (unsigned long)sge->length, dto->offset[i], 667 (unsigned long)regd_buf->reg.len, dto, i, 668 (unsigned long)sge->addr); 669 BUG(); 670 } 671 672 sge->addr += dto->offset[i]; /* Adjust offset */ 673 } 674 } 675 676 /** 677 * iser_post_recv - Posts a receive buffer. 678 * 679 * returns 0 on success, -1 on failure 680 */ 681 int iser_post_recv(struct iser_desc *rx_desc) 682 { 683 int ib_ret, ret_val = 0; 684 struct ib_recv_wr recv_wr, *recv_wr_failed; 685 struct ib_sge iov[2]; 686 struct iser_conn *ib_conn; 687 struct iser_dto *recv_dto = &rx_desc->dto; 688 689 /* Retrieve conn */ 690 ib_conn = recv_dto->ib_conn; 691 692 iser_dto_to_iov(recv_dto, iov, 2); 693 694 recv_wr.next = NULL; 695 recv_wr.sg_list = iov; 696 recv_wr.num_sge = recv_dto->regd_vector_len; 697 recv_wr.wr_id = (unsigned long)rx_desc; 698 699 atomic_inc(&ib_conn->post_recv_buf_count); 700 ib_ret = ib_post_recv(ib_conn->qp, &recv_wr, &recv_wr_failed); 701 if (ib_ret) { 702 iser_err("ib_post_recv failed ret=%d\n", ib_ret); 703 atomic_dec(&ib_conn->post_recv_buf_count); 704 ret_val = -1; 705 } 706 707 return ret_val; 708 } 709 710 /** 711 * iser_start_send - Initiate a Send DTO operation 712 * 713 * returns 0 on success, -1 on failure 714 */ 715 int iser_post_send(struct iser_desc *tx_desc) 716 { 717 int ib_ret, ret_val = 0; 718 struct ib_send_wr send_wr, *send_wr_failed; 719 struct ib_sge iov[MAX_REGD_BUF_VECTOR_LEN]; 720 struct iser_conn *ib_conn; 721 struct iser_dto *dto = &tx_desc->dto; 722 723 ib_conn = dto->ib_conn; 724 725 iser_dto_to_iov(dto, iov, MAX_REGD_BUF_VECTOR_LEN); 726 727 send_wr.next = NULL; 728 send_wr.wr_id = (unsigned long)tx_desc; 729 send_wr.sg_list = iov; 730 send_wr.num_sge = dto->regd_vector_len; 731 send_wr.opcode = IB_WR_SEND; 732 send_wr.send_flags = dto->notify_enable ? IB_SEND_SIGNALED : 0; 733 734 atomic_inc(&ib_conn->post_send_buf_count); 735 736 ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed); 737 if (ib_ret) { 738 iser_err("Failed to start SEND DTO, dto: 0x%p, IOV len: %d\n", 739 dto, dto->regd_vector_len); 740 iser_err("ib_post_send failed, ret:%d\n", ib_ret); 741 atomic_dec(&ib_conn->post_send_buf_count); 742 ret_val = -1; 743 } 744 745 return ret_val; 746 } 747 748 static void iser_handle_comp_error(struct iser_desc *desc) 749 { 750 struct iser_dto *dto = &desc->dto; 751 struct iser_conn *ib_conn = dto->ib_conn; 752 753 iser_dto_buffs_release(dto); 754 755 if (desc->type == ISCSI_RX) { 756 kfree(desc->data); 757 kmem_cache_free(ig.desc_cache, desc); 758 atomic_dec(&ib_conn->post_recv_buf_count); 759 } else { /* type is TX control/command/dataout */ 760 if (desc->type == ISCSI_TX_DATAOUT) 761 kmem_cache_free(ig.desc_cache, desc); 762 atomic_dec(&ib_conn->post_send_buf_count); 763 } 764 765 if (atomic_read(&ib_conn->post_recv_buf_count) == 0 && 766 atomic_read(&ib_conn->post_send_buf_count) == 0) { 767 /* getting here when the state is UP means that the conn is * 768 * being terminated asynchronously from the iSCSI layer's * 769 * perspective. */ 770 if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP, 771 ISER_CONN_TERMINATING)) 772 iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn, 773 ISCSI_ERR_CONN_FAILED); 774 775 /* complete the termination process if disconnect event was delivered * 776 * note there are no more non completed posts to the QP */ 777 if (ib_conn->disc_evt_flag) { 778 ib_conn->state = ISER_CONN_DOWN; 779 wake_up_interruptible(&ib_conn->wait); 780 } 781 } 782 } 783 784 static void iser_cq_tasklet_fn(unsigned long data) 785 { 786 struct iser_device *device = (struct iser_device *)data; 787 struct ib_cq *cq = device->cq; 788 struct ib_wc wc; 789 struct iser_desc *desc; 790 unsigned long xfer_len; 791 792 while (ib_poll_cq(cq, 1, &wc) == 1) { 793 desc = (struct iser_desc *) (unsigned long) wc.wr_id; 794 BUG_ON(desc == NULL); 795 796 if (wc.status == IB_WC_SUCCESS) { 797 if (desc->type == ISCSI_RX) { 798 xfer_len = (unsigned long)wc.byte_len; 799 iser_rcv_completion(desc, xfer_len); 800 } else /* type == ISCSI_TX_CONTROL/SCSI_CMD/DOUT */ 801 iser_snd_completion(desc); 802 } else { 803 iser_err("comp w. error op %d status %d\n",desc->type,wc.status); 804 iser_handle_comp_error(desc); 805 } 806 } 807 /* #warning "it is assumed here that arming CQ only once its empty" * 808 * " would not cause interrupts to be missed" */ 809 ib_req_notify_cq(cq, IB_CQ_NEXT_COMP); 810 } 811 812 static void iser_cq_callback(struct ib_cq *cq, void *cq_context) 813 { 814 struct iser_device *device = (struct iser_device *)cq_context; 815 816 tasklet_schedule(&device->cq_tasklet); 817 } 818