drivers/infiniband/ulp/iser/iser_verbs.c

   1 /*
   2  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
   3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
   4  * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  */
  34 #include <linux/kernel.h>
  35 #include <linux/module.h>
  36 #include <linux/slab.h>
  37 #include <linux/delay.h>
  38
  39 #include "iscsi_iser.h"
  40
  41 #define ISCSI_ISER_MAX_CONN     8
  42 #define ISER_MAX_RX_LEN         (ISER_QP_MAX_RECV_DTOS * ISCSI_ISER_MAX_CONN)
  43 #define ISER_MAX_TX_LEN         (ISER_QP_MAX_REQ_DTOS  * ISCSI_ISER_MAX_CONN)
  44 #define ISER_MAX_CQ_LEN         (ISER_MAX_RX_LEN + ISER_MAX_TX_LEN + \
  45                                  ISCSI_ISER_MAX_CONN)
  46
  47 static int iser_cq_poll_limit = 512;
  48
  49 static void iser_cq_tasklet_fn(unsigned long data);
  50 static void iser_cq_callback(struct ib_cq *cq, void *cq_context);
  51
  52 static void iser_cq_event_callback(struct ib_event *cause, void *context)
  53 {
  54         iser_err("got cq event %d \n", cause->event);
  55 }
  56
  57 static void iser_qp_event_callback(struct ib_event *cause, void *context)
  58 {
  59         iser_err("got qp event %d\n",cause->event);
  60 }
  61
  62 static void iser_event_handler(struct ib_event_handler *handler,
  63                                 struct ib_event *event)
  64 {
  65         iser_err("async event %d on device %s port %d\n", event->event,
  66                 event->device->name, event->element.port_num);
  67 }
  68
  69 /**
  70  * iser_create_device_ib_res - creates Protection Domain (PD), Completion
  71  * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with
  72  * the adapator.
  73  *
  74  * returns 0 on success, -1 on failure
  75  */
  76 static int iser_create_device_ib_res(struct iser_device *device)
  77 {
  78         struct ib_device_attr *dev_attr = &device->dev_attr;
  79         int ret, i;
  80
  81         ret = ib_query_device(device->ib_device, dev_attr);
  82         if (ret) {
  83                 pr_warn("Query device failed for %s\n", device->ib_device->name);
  84                 return ret;
  85         }
  86
  87         /* Assign function handles  - based on FMR support */
  88         if (device->ib_device->alloc_fmr && device->ib_device->dealloc_fmr &&
  89             device->ib_device->map_phys_fmr && device->ib_device->unmap_fmr) {
  90                 iser_info("FMR supported, using FMR for registration\n");
  91                 device->iser_alloc_rdma_reg_res = iser_create_fmr_pool;
  92                 device->iser_free_rdma_reg_res = iser_free_fmr_pool;
  93                 device->iser_reg_rdma_mem = iser_reg_rdma_mem_fmr;
  94                 device->iser_unreg_rdma_mem = iser_unreg_mem_fmr;
  95         } else
  96         if (dev_attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) {
  97                 iser_info("FastReg supported, using FastReg for registration\n");
  98                 device->iser_alloc_rdma_reg_res = iser_create_fastreg_pool;
  99                 device->iser_free_rdma_reg_res = iser_free_fastreg_pool;
 100                 device->iser_reg_rdma_mem = iser_reg_rdma_mem_fastreg;
 101                 device->iser_unreg_rdma_mem = iser_unreg_mem_fastreg;
 102         } else {
 103                 iser_err("IB device does not support FMRs nor FastRegs, can't register memory\n");
 104                 return -1;
 105         }
 106
 107         device->comps_used = min(ISER_MAX_CQ,
 108                                  device->ib_device->num_comp_vectors);
 109         iser_info("using %d CQs, device %s supports %d vectors\n",
 110                   device->comps_used, device->ib_device->name,
 111                   device->ib_device->num_comp_vectors);
 112
 113         device->pd = ib_alloc_pd(device->ib_device);
 114         if (IS_ERR(device->pd))
 115                 goto pd_err;
 116
 117         for (i = 0; i < device->comps_used; i++) {
 118                 struct iser_comp *comp = &device->comps[i];
 119
 120                 comp->device = device;
 121                 comp->cq = ib_create_cq(device->ib_device,
 122                                         iser_cq_callback,
 123                                         iser_cq_event_callback,
 124                                         (void *)comp,
 125                                         ISER_MAX_CQ_LEN, i);
 126                 if (IS_ERR(comp->cq)) {
 127                         comp->cq = NULL;
 128                         goto cq_err;
 129                 }
 130
 131                 if (ib_req_notify_cq(comp->cq, IB_CQ_NEXT_COMP))
 132                         goto cq_err;
 133
 134                 tasklet_init(&comp->tasklet, iser_cq_tasklet_fn,
 135                              (unsigned long)comp);
 136         }
 137
 138         device->mr = ib_get_dma_mr(device->pd, IB_ACCESS_LOCAL_WRITE |
 139                                    IB_ACCESS_REMOTE_WRITE |
 140                                    IB_ACCESS_REMOTE_READ);
 141         if (IS_ERR(device->mr))
 142                 goto dma_mr_err;
 143
 144         INIT_IB_EVENT_HANDLER(&device->event_handler, device->ib_device,
 145                                 iser_event_handler);
 146         if (ib_register_event_handler(&device->event_handler))
 147                 goto handler_err;
 148
 149         return 0;
 150
 151 handler_err:
 152         ib_dereg_mr(device->mr);
 153 dma_mr_err:
 154         for (i = 0; i < device->comps_used; i++)
 155                 tasklet_kill(&device->comps[i].tasklet);
 156 cq_err:
 157         for (i = 0; i < device->comps_used; i++) {
 158                 struct iser_comp *comp = &device->comps[i];
 159
 160                 if (comp->cq)
 161                         ib_destroy_cq(comp->cq);
 162         }
 163         ib_dealloc_pd(device->pd);
 164 pd_err:
 165         iser_err("failed to allocate an IB resource\n");
 166         return -1;
 167 }
 168
 169 /**
 170  * iser_free_device_ib_res - destroy/dealloc/dereg the DMA MR,
 171  * CQ and PD created with the device associated with the adapator.
 172  */
 173 static void iser_free_device_ib_res(struct iser_device *device)
 174 {
 175         int i;
 176         BUG_ON(device->mr == NULL);
 177
 178         for (i = 0; i < device->comps_used; i++) {
 179                 struct iser_comp *comp = &device->comps[i];
 180
 181                 tasklet_kill(&comp->tasklet);
 182                 ib_destroy_cq(comp->cq);
 183                 comp->cq = NULL;
 184         }
 185
 186         (void)ib_unregister_event_handler(&device->event_handler);
 187         (void)ib_dereg_mr(device->mr);
 188         (void)ib_dealloc_pd(device->pd);
 189
 190         device->mr = NULL;
 191         device->pd = NULL;
 192 }
 193
 194 /**
 195  * iser_create_fmr_pool - Creates FMR pool and page_vector
 196  *
 197  * returns 0 on success, or errno code on failure
 198  */
 199 int iser_create_fmr_pool(struct ib_conn *ib_conn, unsigned cmds_max)
 200 {
 201         struct iser_device *device = ib_conn->device;
 202         struct ib_fmr_pool_param params;
 203         int ret = -ENOMEM;
 204
 205         ib_conn->fmr.page_vec = kmalloc(sizeof(*ib_conn->fmr.page_vec) +
 206                                         (sizeof(u64)*(ISCSI_ISER_SG_TABLESIZE + 1)),
 207                                         GFP_KERNEL);
 208         if (!ib_conn->fmr.page_vec)
 209                 return ret;
 210
 211         ib_conn->fmr.page_vec->pages = (u64 *)(ib_conn->fmr.page_vec + 1);
 212
 213         params.page_shift        = SHIFT_4K;
 214         /* when the first/last SG element are not start/end *
 215          * page aligned, the map whould be of N+1 pages     */
 216         params.max_pages_per_fmr = ISCSI_ISER_SG_TABLESIZE + 1;
 217         /* make the pool size twice the max number of SCSI commands *
 218          * the ML is expected to queue, watermark for unmap at 50%  */
 219         params.pool_size         = cmds_max * 2;
 220         params.dirty_watermark   = cmds_max;
 221         params.cache             = 0;
 222         params.flush_function    = NULL;
 223         params.access            = (IB_ACCESS_LOCAL_WRITE  |
 224                                     IB_ACCESS_REMOTE_WRITE |
 225                                     IB_ACCESS_REMOTE_READ);
 226
 227         ib_conn->fmr.pool = ib_create_fmr_pool(device->pd, &params);
 228         if (!IS_ERR(ib_conn->fmr.pool))
 229                 return 0;
 230
 231         /* no FMR => no need for page_vec */
 232         kfree(ib_conn->fmr.page_vec);
 233         ib_conn->fmr.page_vec = NULL;
 234
 235         ret = PTR_ERR(ib_conn->fmr.pool);
 236         ib_conn->fmr.pool = NULL;
 237         if (ret != -ENOSYS) {
 238                 iser_err("FMR allocation failed, err %d\n", ret);
 239                 return ret;
 240         } else {
 241                 iser_warn("FMRs are not supported, using unaligned mode\n");
 242                 return 0;
 243         }
 244 }
 245
 246 /**
 247  * iser_free_fmr_pool - releases the FMR pool and page vec
 248  */
 249 void iser_free_fmr_pool(struct ib_conn *ib_conn)
 250 {
 251         iser_info("freeing conn %p fmr pool %p\n",
 252                   ib_conn, ib_conn->fmr.pool);
 253
 254         if (ib_conn->fmr.pool != NULL)
 255                 ib_destroy_fmr_pool(ib_conn->fmr.pool);
 256
 257         ib_conn->fmr.pool = NULL;
 258
 259         kfree(ib_conn->fmr.page_vec);
 260         ib_conn->fmr.page_vec = NULL;
 261 }
 262
 263 static int
 264 iser_create_fastreg_desc(struct ib_device *ib_device, struct ib_pd *pd,
 265                          bool pi_enable, struct fast_reg_descriptor *desc)
 266 {
 267         int ret;
 268
 269         desc->data_frpl = ib_alloc_fast_reg_page_list(ib_device,
 270                                                       ISCSI_ISER_SG_TABLESIZE + 1);
 271         if (IS_ERR(desc->data_frpl)) {
 272                 ret = PTR_ERR(desc->data_frpl);
 273                 iser_err("Failed to allocate ib_fast_reg_page_list err=%d\n",
 274                          ret);
 275                 return PTR_ERR(desc->data_frpl);
 276         }
 277
 278         desc->data_mr = ib_alloc_fast_reg_mr(pd, ISCSI_ISER_SG_TABLESIZE + 1);
 279         if (IS_ERR(desc->data_mr)) {
 280                 ret = PTR_ERR(desc->data_mr);
 281                 iser_err("Failed to allocate ib_fast_reg_mr err=%d\n", ret);
 282                 goto fast_reg_mr_failure;
 283         }
 284         desc->reg_indicators |= ISER_DATA_KEY_VALID;
 285
 286         if (pi_enable) {
 287                 struct ib_mr_init_attr mr_init_attr = {0};
 288                 struct iser_pi_context *pi_ctx = NULL;
 289
 290                 desc->pi_ctx = kzalloc(sizeof(*desc->pi_ctx), GFP_KERNEL);
 291                 if (!desc->pi_ctx) {
 292                         iser_err("Failed to allocate pi context\n");
 293                         ret = -ENOMEM;
 294                         goto pi_ctx_alloc_failure;
 295                 }
 296                 pi_ctx = desc->pi_ctx;
 297
 298                 pi_ctx->prot_frpl = ib_alloc_fast_reg_page_list(ib_device,
 299                                                     ISCSI_ISER_SG_TABLESIZE);
 300                 if (IS_ERR(pi_ctx->prot_frpl)) {
 301                         ret = PTR_ERR(pi_ctx->prot_frpl);
 302                         iser_err("Failed to allocate prot frpl ret=%d\n",
 303                                  ret);
 304                         goto prot_frpl_failure;
 305                 }
 306
 307                 pi_ctx->prot_mr = ib_alloc_fast_reg_mr(pd,
 308                                                 ISCSI_ISER_SG_TABLESIZE + 1);
 309                 if (IS_ERR(pi_ctx->prot_mr)) {
 310                         ret = PTR_ERR(pi_ctx->prot_mr);
 311                         iser_err("Failed to allocate prot frmr ret=%d\n",
 312                                  ret);
 313                         goto prot_mr_failure;
 314                 }
 315                 desc->reg_indicators |= ISER_PROT_KEY_VALID;
 316
 317                 mr_init_attr.max_reg_descriptors = 2;
 318                 mr_init_attr.flags |= IB_MR_SIGNATURE_EN;
 319                 pi_ctx->sig_mr = ib_create_mr(pd, &mr_init_attr);
 320                 if (IS_ERR(pi_ctx->sig_mr)) {
 321                         ret = PTR_ERR(pi_ctx->sig_mr);
 322                         iser_err("Failed to allocate signature enabled mr err=%d\n",
 323                                  ret);
 324                         goto sig_mr_failure;
 325                 }
 326                 desc->reg_indicators |= ISER_SIG_KEY_VALID;
 327         }
 328         desc->reg_indicators &= ~ISER_FASTREG_PROTECTED;
 329
 330         iser_dbg("Create fr_desc %p page_list %p\n",
 331                  desc, desc->data_frpl->page_list);
 332
 333         return 0;
 334 sig_mr_failure:
 335         ib_dereg_mr(desc->pi_ctx->prot_mr);
 336 prot_mr_failure:
 337         ib_free_fast_reg_page_list(desc->pi_ctx->prot_frpl);
 338 prot_frpl_failure:
 339         kfree(desc->pi_ctx);
 340 pi_ctx_alloc_failure:
 341         ib_dereg_mr(desc->data_mr);
 342 fast_reg_mr_failure:
 343         ib_free_fast_reg_page_list(desc->data_frpl);
 344
 345         return ret;
 346 }
 347
 348 /**
 349  * iser_create_fastreg_pool - Creates pool of fast_reg descriptors
 350  * for fast registration work requests.
 351  * returns 0 on success, or errno code on failure
 352  */
 353 int iser_create_fastreg_pool(struct ib_conn *ib_conn, unsigned cmds_max)
 354 {
 355         struct iser_device *device = ib_conn->device;
 356         struct fast_reg_descriptor *desc;
 357         int i, ret;
 358
 359         INIT_LIST_HEAD(&ib_conn->fastreg.pool);
 360         ib_conn->fastreg.pool_size = 0;
 361         for (i = 0; i < cmds_max; i++) {
 362                 desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 363                 if (!desc) {
 364                         iser_err("Failed to allocate a new fast_reg descriptor\n");
 365                         ret = -ENOMEM;
 366                         goto err;
 367                 }
 368
 369                 ret = iser_create_fastreg_desc(device->ib_device, device->pd,
 370                                                ib_conn->pi_support, desc);
 371                 if (ret) {
 372                         iser_err("Failed to create fastreg descriptor err=%d\n",
 373                                  ret);
 374                         kfree(desc);
 375                         goto err;
 376                 }
 377
 378                 list_add_tail(&desc->list, &ib_conn->fastreg.pool);
 379                 ib_conn->fastreg.pool_size++;
 380         }
 381
 382         return 0;
 383
 384 err:
 385         iser_free_fastreg_pool(ib_conn);
 386         return ret;
 387 }
 388
 389 /**
 390  * iser_free_fastreg_pool - releases the pool of fast_reg descriptors
 391  */
 392 void iser_free_fastreg_pool(struct ib_conn *ib_conn)
 393 {
 394         struct fast_reg_descriptor *desc, *tmp;
 395         int i = 0;
 396
 397         if (list_empty(&ib_conn->fastreg.pool))
 398                 return;
 399
 400         iser_info("freeing conn %p fr pool\n", ib_conn);
 401
 402         list_for_each_entry_safe(desc, tmp, &ib_conn->fastreg.pool, list) {
 403                 list_del(&desc->list);
 404                 ib_free_fast_reg_page_list(desc->data_frpl);
 405                 ib_dereg_mr(desc->data_mr);
 406                 if (desc->pi_ctx) {
 407                         ib_free_fast_reg_page_list(desc->pi_ctx->prot_frpl);
 408                         ib_dereg_mr(desc->pi_ctx->prot_mr);
 409                         ib_destroy_mr(desc->pi_ctx->sig_mr);
 410                         kfree(desc->pi_ctx);
 411                 }
 412                 kfree(desc);
 413                 ++i;
 414         }
 415
 416         if (i < ib_conn->fastreg.pool_size)
 417                 iser_warn("pool still has %d regions registered\n",
 418                           ib_conn->fastreg.pool_size - i);
 419 }
 420
 421 /**
 422  * iser_create_ib_conn_res - Queue-Pair (QP)
 423  *
 424  * returns 0 on success, -1 on failure
 425  */
 426 static int iser_create_ib_conn_res(struct ib_conn *ib_conn)
 427 {
 428         struct iser_device      *device;
 429         struct ib_qp_init_attr  init_attr;
 430         int                     ret = -ENOMEM;
 431         int index, min_index = 0;
 432
 433         BUG_ON(ib_conn->device == NULL);
 434
 435         device = ib_conn->device;
 436
 437         memset(&init_attr, 0, sizeof init_attr);
 438
 439         mutex_lock(&ig.connlist_mutex);
 440         /* select the CQ with the minimal number of usages */
 441         for (index = 0; index < device->comps_used; index++) {
 442                 if (device->comps[index].active_qps <
 443                     device->comps[min_index].active_qps)
 444                         min_index = index;
 445         }
 446         ib_conn->comp = &device->comps[min_index];
 447         ib_conn->comp->active_qps++;
 448         mutex_unlock(&ig.connlist_mutex);
 449         iser_info("cq index %d used for ib_conn %p\n", min_index, ib_conn);
 450
 451         init_attr.event_handler = iser_qp_event_callback;
 452         init_attr.qp_context    = (void *)ib_conn;
 453         init_attr.send_cq       = ib_conn->comp->cq;
 454         init_attr.recv_cq       = ib_conn->comp->cq;
 455         init_attr.cap.max_recv_wr  = ISER_QP_MAX_RECV_DTOS;
 456         init_attr.cap.max_send_sge = 2;
 457         init_attr.cap.max_recv_sge = 1;
 458         init_attr.sq_sig_type   = IB_SIGNAL_REQ_WR;
 459         init_attr.qp_type       = IB_QPT_RC;
 460         if (ib_conn->pi_support) {
 461                 init_attr.cap.max_send_wr = ISER_QP_SIG_MAX_REQ_DTOS + 1;
 462                 init_attr.create_flags |= IB_QP_CREATE_SIGNATURE_EN;
 463         } else {
 464                 init_attr.cap.max_send_wr  = ISER_QP_MAX_REQ_DTOS + 1;
 465         }
 466
 467         ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr);
 468         if (ret)
 469                 goto out_err;
 470
 471         ib_conn->qp = ib_conn->cma_id->qp;
 472         iser_info("setting conn %p cma_id %p qp %p\n",
 473                   ib_conn, ib_conn->cma_id,
 474                   ib_conn->cma_id->qp);
 475         return ret;
 476
 477 out_err:
 478         iser_err("unable to alloc mem or create resource, err %d\n", ret);
 479         return ret;
 480 }
 481
 482 /**
 483  * based on the resolved device node GUID see if there already allocated
 484  * device for this device. If there's no such, create one.
 485  */
 486 static
 487 struct iser_device *iser_device_find_by_ib_device(struct rdma_cm_id *cma_id)
 488 {
 489         struct iser_device *device;
 490
 491         mutex_lock(&ig.device_list_mutex);
 492
 493         list_for_each_entry(device, &ig.device_list, ig_list)
 494                 /* find if there's a match using the node GUID */
 495                 if (device->ib_device->node_guid == cma_id->device->node_guid)
 496                         goto inc_refcnt;
 497
 498         device = kzalloc(sizeof *device, GFP_KERNEL);
 499         if (device == NULL)
 500                 goto out;
 501
 502         /* assign this device to the device */
 503         device->ib_device = cma_id->device;
 504         /* init the device and link it into ig device list */
 505         if (iser_create_device_ib_res(device)) {
 506                 kfree(device);
 507                 device = NULL;
 508                 goto out;
 509         }
 510         list_add(&device->ig_list, &ig.device_list);
 511
 512 inc_refcnt:
 513         device->refcount++;
 514 out:
 515         mutex_unlock(&ig.device_list_mutex);
 516         return device;
 517 }
 518
 519 /* if there's no demand for this device, release it */
 520 static void iser_device_try_release(struct iser_device *device)
 521 {
 522         mutex_lock(&ig.device_list_mutex);
 523         device->refcount--;
 524         iser_info("device %p refcount %d\n", device, device->refcount);
 525         if (!device->refcount) {
 526                 iser_free_device_ib_res(device);
 527                 list_del(&device->ig_list);
 528                 kfree(device);
 529         }
 530         mutex_unlock(&ig.device_list_mutex);
 531 }
 532
 533 /**
 534  * Called with state mutex held
 535  **/
 536 static int iser_conn_state_comp_exch(struct iser_conn *iser_conn,
 537                                      enum iser_conn_state comp,
 538                                      enum iser_conn_state exch)
 539 {
 540         int ret;
 541
 542         ret = (iser_conn->state == comp);
 543         if (ret)
 544                 iser_conn->state = exch;
 545
 546         return ret;
 547 }
 548
 549 void iser_release_work(struct work_struct *work)
 550 {
 551         struct iser_conn *iser_conn;
 552
 553         iser_conn = container_of(work, struct iser_conn, release_work);
 554
 555         /* Wait for conn_stop to complete */
 556         wait_for_completion(&iser_conn->stop_completion);
 557         /* Wait for IB resouces cleanup to complete */
 558         wait_for_completion(&iser_conn->ib_completion);
 559
 560         mutex_lock(&iser_conn->state_mutex);
 561         iser_conn->state = ISER_CONN_DOWN;
 562         mutex_unlock(&iser_conn->state_mutex);
 563
 564         iser_conn_release(iser_conn);
 565 }
 566
 567 /**
 568  * iser_free_ib_conn_res - release IB related resources
 569  * @iser_conn: iser connection struct
 570  * @destroy_device: indicator if we need to try to release
 571  *     the iser device (only iscsi shutdown and DEVICE_REMOVAL
 572  *     will use this.
 573  *
 574  * This routine is called with the iser state mutex held
 575  * so the cm_id removal is out of here. It is Safe to
 576  * be invoked multiple times.
 577  */
 578 static void iser_free_ib_conn_res(struct iser_conn *iser_conn,
 579                                   bool destroy_device)
 580 {
 581         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 582         struct iser_device *device = ib_conn->device;
 583
 584         iser_info("freeing conn %p cma_id %p qp %p\n",
 585                   iser_conn, ib_conn->cma_id, ib_conn->qp);
 586
 587         iser_free_rx_descriptors(iser_conn);
 588
 589         if (ib_conn->qp != NULL) {
 590                 ib_conn->comp->active_qps--;
 591                 rdma_destroy_qp(ib_conn->cma_id);
 592                 ib_conn->qp = NULL;
 593         }
 594
 595         if (destroy_device && device != NULL) {
 596                 iser_device_try_release(device);
 597                 ib_conn->device = NULL;
 598         }
 599 }
 600
 601 /**
 602  * Frees all conn objects and deallocs conn descriptor
 603  */
 604 void iser_conn_release(struct iser_conn *iser_conn)
 605 {
 606         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 607
 608         mutex_lock(&ig.connlist_mutex);
 609         list_del(&iser_conn->conn_list);
 610         mutex_unlock(&ig.connlist_mutex);
 611
 612         mutex_lock(&iser_conn->state_mutex);
 613         if (iser_conn->state != ISER_CONN_DOWN)
 614                 iser_warn("iser conn %p state %d, expected state down.\n",
 615                           iser_conn, iser_conn->state);
 616         /*
 617          * In case we never got to bind stage, we still need to
 618          * release IB resources (which is safe to call more than once).
 619          */
 620         iser_free_ib_conn_res(iser_conn, true);
 621         mutex_unlock(&iser_conn->state_mutex);
 622
 623         if (ib_conn->cma_id != NULL) {
 624                 rdma_destroy_id(ib_conn->cma_id);
 625                 ib_conn->cma_id = NULL;
 626         }
 627
 628         kfree(iser_conn);
 629 }
 630
 631 /**
 632  * triggers start of the disconnect procedures and wait for them to be done
 633  * Called with state mutex held
 634  */
 635 int iser_conn_terminate(struct iser_conn *iser_conn)
 636 {
 637         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 638         struct ib_send_wr *bad_wr;
 639         int err = 0;
 640
 641         /* terminate the iser conn only if the conn state is UP */
 642         if (!iser_conn_state_comp_exch(iser_conn, ISER_CONN_UP,
 643                                        ISER_CONN_TERMINATING))
 644                 return 0;
 645
 646         iser_info("iser_conn %p state %d\n", iser_conn, iser_conn->state);
 647
 648         /* suspend queuing of new iscsi commands */
 649         if (iser_conn->iscsi_conn)
 650                 iscsi_suspend_queue(iser_conn->iscsi_conn);
 651
 652         /*
 653          * In case we didn't already clean up the cma_id (peer initiated
 654          * a disconnection), we need to Cause the CMA to change the QP
 655          * state to ERROR.
 656          */
 657         if (ib_conn->cma_id) {
 658                 err = rdma_disconnect(ib_conn->cma_id);
 659                 if (err)
 660                         iser_err("Failed to disconnect, conn: 0x%p err %d\n",
 661                                  iser_conn, err);
 662
 663                 /* post an indication that all flush errors were consumed */
 664                 err = ib_post_send(ib_conn->qp, &ib_conn->beacon, &bad_wr);
 665                 if (err)
 666                         iser_err("conn %p failed to post beacon", ib_conn);
 667
 668                 wait_for_completion(&ib_conn->flush_comp);
 669         }
 670
 671         return 1;
 672 }
 673
 674 /**
 675  * Called with state mutex held
 676  **/
 677 static void iser_connect_error(struct rdma_cm_id *cma_id)
 678 {
 679         struct iser_conn *iser_conn;
 680
 681         iser_conn = (struct iser_conn *)cma_id->context;
 682         iser_conn->state = ISER_CONN_DOWN;
 683 }
 684
 685 /**
 686  * Called with state mutex held
 687  **/
 688 static void iser_addr_handler(struct rdma_cm_id *cma_id)
 689 {
 690         struct iser_device *device;
 691         struct iser_conn   *iser_conn;
 692         struct ib_conn   *ib_conn;
 693         int    ret;
 694
 695         iser_conn = (struct iser_conn *)cma_id->context;
 696         if (iser_conn->state != ISER_CONN_PENDING)
 697                 /* bailout */
 698                 return;
 699
 700         ib_conn = &iser_conn->ib_conn;
 701         device = iser_device_find_by_ib_device(cma_id);
 702         if (!device) {
 703                 iser_err("device lookup/creation failed\n");
 704                 iser_connect_error(cma_id);
 705                 return;
 706         }
 707
 708         ib_conn->device = device;
 709
 710         /* connection T10-PI support */
 711         if (iser_pi_enable) {
 712                 if (!(device->dev_attr.device_cap_flags &
 713                       IB_DEVICE_SIGNATURE_HANDOVER)) {
 714                         iser_warn("T10-PI requested but not supported on %s, "
 715                                   "continue without T10-PI\n",
 716                                   ib_conn->device->ib_device->name);
 717                         ib_conn->pi_support = false;
 718                 } else {
 719                         ib_conn->pi_support = true;
 720                 }
 721         }
 722
 723         ret = rdma_resolve_route(cma_id, 1000);
 724         if (ret) {
 725                 iser_err("resolve route failed: %d\n", ret);
 726                 iser_connect_error(cma_id);
 727                 return;
 728         }
 729 }
 730
 731 /**
 732  * Called with state mutex held
 733  **/
 734 static void iser_route_handler(struct rdma_cm_id *cma_id)
 735 {
 736         struct rdma_conn_param conn_param;
 737         int    ret;
 738         struct iser_cm_hdr req_hdr;
 739         struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;
 740         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 741         struct iser_device *device = ib_conn->device;
 742
 743         if (iser_conn->state != ISER_CONN_PENDING)
 744                 /* bailout */
 745                 return;
 746
 747         ret = iser_create_ib_conn_res(ib_conn);
 748         if (ret)
 749                 goto failure;
 750
 751         memset(&conn_param, 0, sizeof conn_param);
 752         conn_param.responder_resources = device->dev_attr.max_qp_rd_atom;
 753         conn_param.initiator_depth     = 1;
 754         conn_param.retry_count         = 7;
 755         conn_param.rnr_retry_count     = 6;
 756
 757         memset(&req_hdr, 0, sizeof(req_hdr));
 758         req_hdr.flags = (ISER_ZBVA_NOT_SUPPORTED |
 759                         ISER_SEND_W_INV_NOT_SUPPORTED);
 760         conn_param.private_data         = (void *)&req_hdr;
 761         conn_param.private_data_len     = sizeof(struct iser_cm_hdr);
 762
 763         ret = rdma_connect(cma_id, &conn_param);
 764         if (ret) {
 765                 iser_err("failure connecting: %d\n", ret);
 766                 goto failure;
 767         }
 768
 769         return;
 770 failure:
 771         iser_connect_error(cma_id);
 772 }
 773
 774 static void iser_connected_handler(struct rdma_cm_id *cma_id)
 775 {
 776         struct iser_conn *iser_conn;
 777         struct ib_qp_attr attr;
 778         struct ib_qp_init_attr init_attr;
 779
 780         iser_conn = (struct iser_conn *)cma_id->context;
 781         if (iser_conn->state != ISER_CONN_PENDING)
 782                 /* bailout */
 783                 return;
 784
 785         (void)ib_query_qp(cma_id->qp, &attr, ~0, &init_attr);
 786         iser_info("remote qpn:%x my qpn:%x\n", attr.dest_qp_num, cma_id->qp->qp_num);
 787
 788         iser_conn->state = ISER_CONN_UP;
 789         complete(&iser_conn->up_completion);
 790 }
 791
 792 static void iser_disconnected_handler(struct rdma_cm_id *cma_id)
 793 {
 794         struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;
 795
 796         if (iser_conn_terminate(iser_conn)) {
 797                 if (iser_conn->iscsi_conn)
 798                         iscsi_conn_failure(iser_conn->iscsi_conn,
 799                                            ISCSI_ERR_CONN_FAILED);
 800                 else
 801                         iser_err("iscsi_iser connection isn't bound\n");
 802         }
 803 }
 804
 805 static void iser_cleanup_handler(struct rdma_cm_id *cma_id,
 806                                  bool destroy_device)
 807 {
 808         struct iser_conn *iser_conn = (struct iser_conn *)cma_id->context;
 809
 810         /*
 811          * We are not guaranteed that we visited disconnected_handler
 812          * by now, call it here to be safe that we handle CM drep
 813          * and flush errors.
 814          */
 815         iser_disconnected_handler(cma_id);
 816         iser_free_ib_conn_res(iser_conn, destroy_device);
 817         complete(&iser_conn->ib_completion);
 818 };
 819
 820 static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
 821 {
 822         struct iser_conn *iser_conn;
 823         int ret = 0;
 824
 825         iser_conn = (struct iser_conn *)cma_id->context;
 826         iser_info("event %d status %d conn %p id %p\n",
 827                   event->event, event->status, cma_id->context, cma_id);
 828
 829         mutex_lock(&iser_conn->state_mutex);
 830         switch (event->event) {
 831         case RDMA_CM_EVENT_ADDR_RESOLVED:
 832                 iser_addr_handler(cma_id);
 833                 break;
 834         case RDMA_CM_EVENT_ROUTE_RESOLVED:
 835                 iser_route_handler(cma_id);
 836                 break;
 837         case RDMA_CM_EVENT_ESTABLISHED:
 838                 iser_connected_handler(cma_id);
 839                 break;
 840         case RDMA_CM_EVENT_ADDR_ERROR:
 841         case RDMA_CM_EVENT_ROUTE_ERROR:
 842         case RDMA_CM_EVENT_CONNECT_ERROR:
 843         case RDMA_CM_EVENT_UNREACHABLE:
 844         case RDMA_CM_EVENT_REJECTED:
 845                 iser_connect_error(cma_id);
 846                 break;
 847         case RDMA_CM_EVENT_DISCONNECTED:
 848         case RDMA_CM_EVENT_ADDR_CHANGE:
 849                 iser_disconnected_handler(cma_id);
 850                 break;
 851         case RDMA_CM_EVENT_DEVICE_REMOVAL:
 852                 /*
 853                  * we *must* destroy the device as we cannot rely
 854                  * on iscsid to be around to initiate error handling.
 855                  * also implicitly destroy the cma_id.
 856                  */
 857                 iser_cleanup_handler(cma_id, true);
 858                 iser_conn->ib_conn.cma_id = NULL;
 859                 ret = 1;
 860                 break;
 861         case RDMA_CM_EVENT_TIMEWAIT_EXIT:
 862                 iser_cleanup_handler(cma_id, false);
 863                 break;
 864         default:
 865                 iser_err("Unexpected RDMA CM event (%d)\n", event->event);
 866                 break;
 867         }
 868         mutex_unlock(&iser_conn->state_mutex);
 869
 870         return ret;
 871 }
 872
 873 void iser_conn_init(struct iser_conn *iser_conn)
 874 {
 875         iser_conn->state = ISER_CONN_INIT;
 876         iser_conn->ib_conn.post_recv_buf_count = 0;
 877         init_completion(&iser_conn->ib_conn.flush_comp);
 878         init_completion(&iser_conn->stop_completion);
 879         init_completion(&iser_conn->ib_completion);
 880         init_completion(&iser_conn->up_completion);
 881         INIT_LIST_HEAD(&iser_conn->conn_list);
 882         spin_lock_init(&iser_conn->ib_conn.lock);
 883         mutex_init(&iser_conn->state_mutex);
 884 }
 885
 886  /**
 887  * starts the process of connecting to the target
 888  * sleeps until the connection is established or rejected
 889  */
 890 int iser_connect(struct iser_conn   *iser_conn,
 891                  struct sockaddr    *src_addr,
 892                  struct sockaddr    *dst_addr,
 893                  int                 non_blocking)
 894 {
 895         struct ib_conn *ib_conn = &iser_conn->ib_conn;
 896         int err = 0;
 897
 898         mutex_lock(&iser_conn->state_mutex);
 899
 900         sprintf(iser_conn->name, "%pISp", dst_addr);
 901
 902         iser_info("connecting to: %s\n", iser_conn->name);
 903
 904         /* the device is known only --after-- address resolution */
 905         ib_conn->device = NULL;
 906
 907         iser_conn->state = ISER_CONN_PENDING;
 908
 909         ib_conn->beacon.wr_id = ISER_BEACON_WRID;
 910         ib_conn->beacon.opcode = IB_WR_SEND;
 911
 912         ib_conn->cma_id = rdma_create_id(iser_cma_handler,
 913                                          (void *)iser_conn,
 914                                          RDMA_PS_TCP, IB_QPT_RC);
 915         if (IS_ERR(ib_conn->cma_id)) {
 916                 err = PTR_ERR(ib_conn->cma_id);
 917                 iser_err("rdma_create_id failed: %d\n", err);
 918                 goto id_failure;
 919         }
 920
 921         err = rdma_resolve_addr(ib_conn->cma_id, src_addr, dst_addr, 1000);
 922         if (err) {
 923                 iser_err("rdma_resolve_addr failed: %d\n", err);
 924                 goto addr_failure;
 925         }
 926
 927         if (!non_blocking) {
 928                 wait_for_completion_interruptible(&iser_conn->up_completion);
 929
 930                 if (iser_conn->state != ISER_CONN_UP) {
 931                         err =  -EIO;
 932                         goto connect_failure;
 933                 }
 934         }
 935         mutex_unlock(&iser_conn->state_mutex);
 936
 937         mutex_lock(&ig.connlist_mutex);
 938         list_add(&iser_conn->conn_list, &ig.connlist);
 939         mutex_unlock(&ig.connlist_mutex);
 940         return 0;
 941
 942 id_failure:
 943         ib_conn->cma_id = NULL;
 944 addr_failure:
 945         iser_conn->state = ISER_CONN_DOWN;
 946 connect_failure:
 947         mutex_unlock(&iser_conn->state_mutex);
 948         iser_conn_release(iser_conn);
 949         return err;
 950 }
 951
 952 /**
 953  * iser_reg_page_vec - Register physical memory
 954  *
 955  * returns: 0 on success, errno code on failure
 956  */
 957 int iser_reg_page_vec(struct ib_conn *ib_conn,
 958                       struct iser_page_vec *page_vec,
 959                       struct iser_mem_reg  *mem_reg)
 960 {
 961         struct ib_pool_fmr *mem;
 962         u64                io_addr;
 963         u64                *page_list;
 964         int                status;
 965
 966         page_list = page_vec->pages;
 967         io_addr   = page_list[0];
 968
 969         mem  = ib_fmr_pool_map_phys(ib_conn->fmr.pool,
 970                                     page_list,
 971                                     page_vec->length,
 972                                     io_addr);
 973
 974         if (IS_ERR(mem)) {
 975                 status = (int)PTR_ERR(mem);
 976                 iser_err("ib_fmr_pool_map_phys failed: %d\n", status);
 977                 return status;
 978         }
 979
 980         mem_reg->lkey  = mem->fmr->lkey;
 981         mem_reg->rkey  = mem->fmr->rkey;
 982         mem_reg->len   = page_vec->length * SIZE_4K;
 983         mem_reg->va    = io_addr;
 984         mem_reg->is_mr = 1;
 985         mem_reg->mem_h = (void *)mem;
 986
 987         mem_reg->va   += page_vec->offset;
 988         mem_reg->len   = page_vec->data_size;
 989
 990         iser_dbg("PHYSICAL Mem.register, [PHYS p_array: 0x%p, sz: %d, "
 991                  "entry[0]: (0x%08lx,%ld)] -> "
 992                  "[lkey: 0x%08X mem_h: 0x%p va: 0x%08lX sz: %ld]\n",
 993                  page_vec, page_vec->length,
 994                  (unsigned long)page_vec->pages[0],
 995                  (unsigned long)page_vec->data_size,
 996                  (unsigned int)mem_reg->lkey, mem_reg->mem_h,
 997                  (unsigned long)mem_reg->va, (unsigned long)mem_reg->len);
 998         return 0;
 999 }
1000
1001 /**
1002  * Unregister (previosuly registered using FMR) memory.
1003  * If memory is non-FMR does nothing.
1004  */
1005 void iser_unreg_mem_fmr(struct iscsi_iser_task *iser_task,
1006                         enum iser_data_dir cmd_dir)
1007 {
1008         struct iser_mem_reg *reg = &iser_task->rdma_regd[cmd_dir].reg;
1009         int ret;
1010
1011         if (!reg->is_mr)
1012                 return;
1013
1014         iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n",reg->mem_h);
1015
1016         ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h);
1017         if (ret)
1018                 iser_err("ib_fmr_pool_unmap failed %d\n", ret);
1019
1020         reg->mem_h = NULL;
1021 }
1022
1023 void iser_unreg_mem_fastreg(struct iscsi_iser_task *iser_task,
1024                             enum iser_data_dir cmd_dir)
1025 {
1026         struct iser_mem_reg *reg = &iser_task->rdma_regd[cmd_dir].reg;
1027         struct iser_conn *iser_conn = iser_task->iser_conn;
1028         struct ib_conn *ib_conn = &iser_conn->ib_conn;
1029         struct fast_reg_descriptor *desc = reg->mem_h;
1030
1031         if (!reg->is_mr)
1032                 return;
1033
1034         reg->mem_h = NULL;
1035         reg->is_mr = 0;
1036         spin_lock_bh(&ib_conn->lock);
1037         list_add_tail(&desc->list, &ib_conn->fastreg.pool);
1038         spin_unlock_bh(&ib_conn->lock);
1039 }
1040
1041 int iser_post_recvl(struct iser_conn *iser_conn)
1042 {
1043         struct ib_recv_wr rx_wr, *rx_wr_failed;
1044         struct ib_conn *ib_conn = &iser_conn->ib_conn;
1045         struct ib_sge     sge;
1046         int ib_ret;
1047
1048         sge.addr   = iser_conn->login_resp_dma;
1049         sge.length = ISER_RX_LOGIN_SIZE;
1050         sge.lkey   = ib_conn->device->mr->lkey;
1051
1052         rx_wr.wr_id   = (unsigned long)iser_conn->login_resp_buf;
1053         rx_wr.sg_list = &sge;
1054         rx_wr.num_sge = 1;
1055         rx_wr.next    = NULL;
1056
1057         ib_conn->post_recv_buf_count++;
1058         ib_ret  = ib_post_recv(ib_conn->qp, &rx_wr, &rx_wr_failed);
1059         if (ib_ret) {
1060                 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
1061                 ib_conn->post_recv_buf_count--;
1062         }
1063         return ib_ret;
1064 }
1065
1066 int iser_post_recvm(struct iser_conn *iser_conn, int count)
1067 {
1068         struct ib_recv_wr *rx_wr, *rx_wr_failed;
1069         int i, ib_ret;
1070         struct ib_conn *ib_conn = &iser_conn->ib_conn;
1071         unsigned int my_rx_head = iser_conn->rx_desc_head;
1072         struct iser_rx_desc *rx_desc;
1073
1074         for (rx_wr = ib_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
1075                 rx_desc         = &iser_conn->rx_descs[my_rx_head];
1076                 rx_wr->wr_id    = (unsigned long)rx_desc;
1077                 rx_wr->sg_list  = &rx_desc->rx_sg;
1078                 rx_wr->num_sge  = 1;
1079                 rx_wr->next     = rx_wr + 1;
1080                 my_rx_head = (my_rx_head + 1) & iser_conn->qp_max_recv_dtos_mask;
1081         }
1082
1083         rx_wr--;
1084         rx_wr->next = NULL; /* mark end of work requests list */
1085
1086         ib_conn->post_recv_buf_count += count;
1087         ib_ret  = ib_post_recv(ib_conn->qp, ib_conn->rx_wr, &rx_wr_failed);
1088         if (ib_ret) {
1089                 iser_err("ib_post_recv failed ret=%d\n", ib_ret);
1090                 ib_conn->post_recv_buf_count -= count;
1091         } else
1092                 iser_conn->rx_desc_head = my_rx_head;
1093         return ib_ret;
1094 }
1095
1096
1097 /**
1098  * iser_start_send - Initiate a Send DTO operation
1099  *
1100  * returns 0 on success, -1 on failure
1101  */
1102 int iser_post_send(struct ib_conn *ib_conn, struct iser_tx_desc *tx_desc,
1103                    bool signal)
1104 {
1105         int               ib_ret;
1106         struct ib_send_wr send_wr, *send_wr_failed;
1107
1108         ib_dma_sync_single_for_device(ib_conn->device->ib_device,
1109                                       tx_desc->dma_addr, ISER_HEADERS_LEN,
1110                                       DMA_TO_DEVICE);
1111
1112         send_wr.next       = NULL;
1113         send_wr.wr_id      = (unsigned long)tx_desc;
1114         send_wr.sg_list    = tx_desc->tx_sg;
1115         send_wr.num_sge    = tx_desc->num_sge;
1116         send_wr.opcode     = IB_WR_SEND;
1117         send_wr.send_flags = signal ? IB_SEND_SIGNALED : 0;
1118
1119         ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed);
1120         if (ib_ret)
1121                 iser_err("ib_post_send failed, ret:%d\n", ib_ret);
1122
1123         return ib_ret;
1124 }
1125
1126 /**
1127  * is_iser_tx_desc - Indicate if the completion wr_id
1128  *     is a TX descriptor or not.
1129  * @iser_conn: iser connection
1130  * @wr_id: completion WR identifier
1131  *
1132  * Since we cannot rely on wc opcode in FLUSH errors
1133  * we must work around it by checking if the wr_id address
1134  * falls in the iser connection rx_descs buffer. If so
1135  * it is an RX descriptor, otherwize it is a TX.
1136  */
1137 static inline bool
1138 is_iser_tx_desc(struct iser_conn *iser_conn, void *wr_id)
1139 {
1140         void *start = iser_conn->rx_descs;
1141         int len = iser_conn->num_rx_descs * sizeof(*iser_conn->rx_descs);
1142
1143         if (wr_id >= start && wr_id < start + len)
1144                 return false;
1145
1146         return true;
1147 }
1148
1149 /**
1150  * iser_handle_comp_error() - Handle error completion
1151  * @ib_conn:   connection RDMA resources
1152  * @wc:        work completion
1153  *
1154  * Notes: We may handle a FLUSH error completion and in this case
1155  *        we only cleanup in case TX type was DATAOUT. For non-FLUSH
1156  *        error completion we should also notify iscsi layer that
1157  *        connection is failed (in case we passed bind stage).
1158  */
1159 static void
1160 iser_handle_comp_error(struct ib_conn *ib_conn,
1161                        struct ib_wc *wc)
1162 {
1163         struct iser_conn *iser_conn = container_of(ib_conn, struct iser_conn,
1164                                                    ib_conn);
1165
1166         if (wc->status != IB_WC_WR_FLUSH_ERR)
1167                 if (iser_conn->iscsi_conn)
1168                         iscsi_conn_failure(iser_conn->iscsi_conn,
1169                                            ISCSI_ERR_CONN_FAILED);
1170
1171         if (is_iser_tx_desc(iser_conn, (void *)wc->wr_id)) {
1172                 struct iser_tx_desc *desc = (struct iser_tx_desc *)wc->wr_id;
1173
1174                 if (desc->type == ISCSI_TX_DATAOUT)
1175                         kmem_cache_free(ig.desc_cache, desc);
1176         } else {
1177                 ib_conn->post_recv_buf_count--;
1178         }
1179 }
1180
1181 /**
1182  * iser_handle_wc - handle a single work completion
1183  * @wc: work completion
1184  *
1185  * Soft-IRQ context, work completion can be either
1186  * SEND or RECV, and can turn out successful or
1187  * with error (or flush error).
1188  */
1189 static void iser_handle_wc(struct ib_wc *wc)
1190 {
1191         struct ib_conn *ib_conn;
1192         struct iser_tx_desc *tx_desc;
1193         struct iser_rx_desc *rx_desc;
1194
1195         ib_conn = wc->qp->qp_context;
1196         if (wc->status == IB_WC_SUCCESS) {
1197                 if (wc->opcode == IB_WC_RECV) {
1198                         rx_desc = (struct iser_rx_desc *)wc->wr_id;
1199                         iser_rcv_completion(rx_desc, wc->byte_len,
1200                                             ib_conn);
1201                 } else
1202                 if (wc->opcode == IB_WC_SEND) {
1203                         tx_desc = (struct iser_tx_desc *)wc->wr_id;
1204                         iser_snd_completion(tx_desc, ib_conn);
1205                 } else {
1206                         iser_err("Unknown wc opcode %d\n", wc->opcode);
1207                 }
1208         } else {
1209                 if (wc->status != IB_WC_WR_FLUSH_ERR)
1210                         iser_err("wr id %llx status %d vend_err %x\n",
1211                                  wc->wr_id, wc->status, wc->vendor_err);
1212                 else
1213                         iser_dbg("flush error: wr id %llx\n", wc->wr_id);
1214
1215                 if (wc->wr_id != ISER_FASTREG_LI_WRID &&
1216                     wc->wr_id != ISER_BEACON_WRID)
1217                         iser_handle_comp_error(ib_conn, wc);
1218
1219                 /* complete in case all flush errors were consumed */
1220                 if (wc->wr_id == ISER_BEACON_WRID)
1221                         complete(&ib_conn->flush_comp);
1222         }
1223 }
1224
1225 /**
1226  * iser_cq_tasklet_fn - iSER completion polling loop
1227  * @data: iSER completion context
1228  *
1229  * Soft-IRQ context, polling connection CQ until
1230  * either CQ was empty or we exausted polling budget
1231  */
1232 static void iser_cq_tasklet_fn(unsigned long data)
1233 {
1234         struct iser_comp *comp = (struct iser_comp *)data;
1235         struct ib_cq *cq = comp->cq;
1236         struct ib_wc *const wcs = comp->wcs;
1237         int i, n, completed = 0;
1238
1239         while ((n = ib_poll_cq(cq, ARRAY_SIZE(comp->wcs), wcs)) > 0) {
1240                 for (i = 0; i < n; i++)
1241                         iser_handle_wc(&wcs[i]);
1242
1243                 completed += n;
1244                 if (completed >= iser_cq_poll_limit)
1245                         break;
1246         }
1247
1248         /*
1249          * It is assumed here that arming CQ only once its empty
1250          * would not cause interrupts to be missed.
1251          */
1252         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1253
1254         iser_dbg("got %d completions\n", completed);
1255 }
1256
1257 static void iser_cq_callback(struct ib_cq *cq, void *cq_context)
1258 {
1259         struct iser_comp *comp = cq_context;
1260
1261         tasklet_schedule(&comp->tasklet);
1262 }
1263
1264 u8 iser_check_task_pi_status(struct iscsi_iser_task *iser_task,
1265                              enum iser_data_dir cmd_dir, sector_t *sector)
1266 {
1267         struct iser_mem_reg *reg = &iser_task->rdma_regd[cmd_dir].reg;
1268         struct fast_reg_descriptor *desc = reg->mem_h;
1269         unsigned long sector_size = iser_task->sc->device->sector_size;
1270         struct ib_mr_status mr_status;
1271         int ret;
1272
1273         if (desc && desc->reg_indicators & ISER_FASTREG_PROTECTED) {
1274                 desc->reg_indicators &= ~ISER_FASTREG_PROTECTED;
1275                 ret = ib_check_mr_status(desc->pi_ctx->sig_mr,
1276                                          IB_MR_CHECK_SIG_STATUS, &mr_status);
1277                 if (ret) {
1278                         pr_err("ib_check_mr_status failed, ret %d\n", ret);
1279                         goto err;
1280                 }
1281
1282                 if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
1283                         sector_t sector_off = mr_status.sig_err.sig_err_offset;
1284
1285                         do_div(sector_off, sector_size + 8);
1286                         *sector = scsi_get_lba(iser_task->sc) + sector_off;
1287
1288                         pr_err("PI error found type %d at sector %llx "
1289                                "expected %x vs actual %x\n",
1290                                mr_status.sig_err.err_type,
1291                                (unsigned long long)*sector,
1292                                mr_status.sig_err.expected,
1293                                mr_status.sig_err.actual);
1294
1295                         switch (mr_status.sig_err.err_type) {
1296                         case IB_SIG_BAD_GUARD:
1297                                 return 0x1;
1298                         case IB_SIG_BAD_REFTAG:
1299                                 return 0x3;
1300                         case IB_SIG_BAD_APPTAG:
1301                                 return 0x2;
1302                         }
1303                 }
1304         }
1305
1306         return 0;
1307 err:
1308         /* Not alot we can do here, return ambiguous guard error */
1309         return 0x1;
1310 }