drivers/infiniband/ulp/srp/ib_srp.c

   1 /*
   2  * Copyright (c) 2005 Cisco Systems.  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
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #define pr_fmt(fmt) PFX fmt
  34
  35 #include <linux/module.h>
  36 #include <linux/init.h>
  37 #include <linux/slab.h>
  38 #include <linux/err.h>
  39 #include <linux/string.h>
  40 #include <linux/parser.h>
  41 #include <linux/random.h>
  42 #include <linux/jiffies.h>
  43
  44 #include <linux/atomic.h>
  45
  46 #include <scsi/scsi.h>
  47 #include <scsi/scsi_device.h>
  48 #include <scsi/scsi_dbg.h>
  49 #include <scsi/srp.h>
  50 #include <scsi/scsi_transport_srp.h>
  51
  52 #include "ib_srp.h"
  53
  54 #define DRV_NAME        "ib_srp"
  55 #define PFX             DRV_NAME ": "
  56 #define DRV_VERSION     "0.2"
  57 #define DRV_RELDATE     "November 1, 2005"
  58
  59 MODULE_AUTHOR("Roland Dreier");
  60 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
  61                    "v" DRV_VERSION " (" DRV_RELDATE ")");
  62 MODULE_LICENSE("Dual BSD/GPL");
  63
  64 static unsigned int srp_sg_tablesize;
  65 static unsigned int cmd_sg_entries;
  66 static unsigned int indirect_sg_entries;
  67 static bool allow_ext_sg;
  68 static int topspin_workarounds = 1;
  69
  70 module_param(srp_sg_tablesize, uint, 0444);
  71 MODULE_PARM_DESC(srp_sg_tablesize, "Deprecated name for cmd_sg_entries");
  72
  73 module_param(cmd_sg_entries, uint, 0444);
  74 MODULE_PARM_DESC(cmd_sg_entries,
  75                  "Default number of gather/scatter entries in the SRP command (default is 12, max 255)");
  76
  77 module_param(indirect_sg_entries, uint, 0444);
  78 MODULE_PARM_DESC(indirect_sg_entries,
  79                  "Default max number of gather/scatter entries (default is 12, max is " __stringify(SCSI_MAX_SG_CHAIN_SEGMENTS) ")");
  80
  81 module_param(allow_ext_sg, bool, 0444);
  82 MODULE_PARM_DESC(allow_ext_sg,
  83                   "Default behavior when there are more than cmd_sg_entries S/G entries after mapping; fails the request when false (default false)");
  84
  85 module_param(topspin_workarounds, int, 0444);
  86 MODULE_PARM_DESC(topspin_workarounds,
  87                  "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
  88
  89 static void srp_add_one(struct ib_device *device);
  90 static void srp_remove_one(struct ib_device *device);
  91 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);
  92 static void srp_send_completion(struct ib_cq *cq, void *target_ptr);
  93 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
  94
  95 static struct scsi_transport_template *ib_srp_transport_template;
  96
  97 static struct ib_client srp_client = {
  98         .name   = "srp",
  99         .add    = srp_add_one,
 100         .remove = srp_remove_one
 101 };
 102
 103 static struct ib_sa_client srp_sa_client;
 104
 105 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
 106 {
 107         return (struct srp_target_port *) host->hostdata;
 108 }
 109
 110 static const char *srp_target_info(struct Scsi_Host *host)
 111 {
 112         return host_to_target(host)->target_name;
 113 }
 114
 115 static int srp_target_is_topspin(struct srp_target_port *target)
 116 {
 117         static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
 118         static const u8 cisco_oui[3]   = { 0x00, 0x1b, 0x0d };
 119
 120         return topspin_workarounds &&
 121                 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
 122                  !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
 123 }
 124
 125 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
 126                                    gfp_t gfp_mask,
 127                                    enum dma_data_direction direction)
 128 {
 129         struct srp_iu *iu;
 130
 131         iu = kmalloc(sizeof *iu, gfp_mask);
 132         if (!iu)
 133                 goto out;
 134
 135         iu->buf = kzalloc(size, gfp_mask);
 136         if (!iu->buf)
 137                 goto out_free_iu;
 138
 139         iu->dma = ib_dma_map_single(host->srp_dev->dev, iu->buf, size,
 140                                     direction);
 141         if (ib_dma_mapping_error(host->srp_dev->dev, iu->dma))
 142                 goto out_free_buf;
 143
 144         iu->size      = size;
 145         iu->direction = direction;
 146
 147         return iu;
 148
 149 out_free_buf:
 150         kfree(iu->buf);
 151 out_free_iu:
 152         kfree(iu);
 153 out:
 154         return NULL;
 155 }
 156
 157 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
 158 {
 159         if (!iu)
 160                 return;
 161
 162         ib_dma_unmap_single(host->srp_dev->dev, iu->dma, iu->size,
 163                             iu->direction);
 164         kfree(iu->buf);
 165         kfree(iu);
 166 }
 167
 168 static void srp_qp_event(struct ib_event *event, void *context)
 169 {
 170         pr_debug("QP event %d\n", event->event);
 171 }
 172
 173 static int srp_init_qp(struct srp_target_port *target,
 174                        struct ib_qp *qp)
 175 {
 176         struct ib_qp_attr *attr;
 177         int ret;
 178
 179         attr = kmalloc(sizeof *attr, GFP_KERNEL);
 180         if (!attr)
 181                 return -ENOMEM;
 182
 183         ret = ib_find_pkey(target->srp_host->srp_dev->dev,
 184                            target->srp_host->port,
 185                            be16_to_cpu(target->path.pkey),
 186                            &attr->pkey_index);
 187         if (ret)
 188                 goto out;
 189
 190         attr->qp_state        = IB_QPS_INIT;
 191         attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
 192                                     IB_ACCESS_REMOTE_WRITE);
 193         attr->port_num        = target->srp_host->port;
 194
 195         ret = ib_modify_qp(qp, attr,
 196                            IB_QP_STATE          |
 197                            IB_QP_PKEY_INDEX     |
 198                            IB_QP_ACCESS_FLAGS   |
 199                            IB_QP_PORT);
 200
 201 out:
 202         kfree(attr);
 203         return ret;
 204 }
 205
 206 static int srp_new_cm_id(struct srp_target_port *target)
 207 {
 208         struct ib_cm_id *new_cm_id;
 209
 210         new_cm_id = ib_create_cm_id(target->srp_host->srp_dev->dev,
 211                                     srp_cm_handler, target);
 212         if (IS_ERR(new_cm_id))
 213                 return PTR_ERR(new_cm_id);
 214
 215         if (target->cm_id)
 216                 ib_destroy_cm_id(target->cm_id);
 217         target->cm_id = new_cm_id;
 218
 219         return 0;
 220 }
 221
 222 static int srp_create_target_ib(struct srp_target_port *target)
 223 {
 224         struct ib_qp_init_attr *init_attr;
 225         int ret;
 226
 227         init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
 228         if (!init_attr)
 229                 return -ENOMEM;
 230
 231         target->recv_cq = ib_create_cq(target->srp_host->srp_dev->dev,
 232                                        srp_recv_completion, NULL, target, SRP_RQ_SIZE, 0);
 233         if (IS_ERR(target->recv_cq)) {
 234                 ret = PTR_ERR(target->recv_cq);
 235                 goto err;
 236         }
 237
 238         target->send_cq = ib_create_cq(target->srp_host->srp_dev->dev,
 239                                        srp_send_completion, NULL, target, SRP_SQ_SIZE, 0);
 240         if (IS_ERR(target->send_cq)) {
 241                 ret = PTR_ERR(target->send_cq);
 242                 goto err_recv_cq;
 243         }
 244
 245         ib_req_notify_cq(target->recv_cq, IB_CQ_NEXT_COMP);
 246
 247         init_attr->event_handler       = srp_qp_event;
 248         init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
 249         init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
 250         init_attr->cap.max_recv_sge    = 1;
 251         init_attr->cap.max_send_sge    = 1;
 252         init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
 253         init_attr->qp_type             = IB_QPT_RC;
 254         init_attr->send_cq             = target->send_cq;
 255         init_attr->recv_cq             = target->recv_cq;
 256
 257         target->qp = ib_create_qp(target->srp_host->srp_dev->pd, init_attr);
 258         if (IS_ERR(target->qp)) {
 259                 ret = PTR_ERR(target->qp);
 260                 goto err_send_cq;
 261         }
 262
 263         ret = srp_init_qp(target, target->qp);
 264         if (ret)
 265                 goto err_qp;
 266
 267         kfree(init_attr);
 268         return 0;
 269
 270 err_qp:
 271         ib_destroy_qp(target->qp);
 272
 273 err_send_cq:
 274         ib_destroy_cq(target->send_cq);
 275
 276 err_recv_cq:
 277         ib_destroy_cq(target->recv_cq);
 278
 279 err:
 280         kfree(init_attr);
 281         return ret;
 282 }
 283
 284 static void srp_free_target_ib(struct srp_target_port *target)
 285 {
 286         int i;
 287
 288         ib_destroy_qp(target->qp);
 289         ib_destroy_cq(target->send_cq);
 290         ib_destroy_cq(target->recv_cq);
 291
 292         for (i = 0; i < SRP_RQ_SIZE; ++i)
 293                 srp_free_iu(target->srp_host, target->rx_ring[i]);
 294         for (i = 0; i < SRP_SQ_SIZE; ++i)
 295                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 296 }
 297
 298 static void srp_path_rec_completion(int status,
 299                                     struct ib_sa_path_rec *pathrec,
 300                                     void *target_ptr)
 301 {
 302         struct srp_target_port *target = target_ptr;
 303
 304         target->status = status;
 305         if (status)
 306                 shost_printk(KERN_ERR, target->scsi_host,
 307                              PFX "Got failed path rec status %d\n", status);
 308         else
 309                 target->path = *pathrec;
 310         complete(&target->done);
 311 }
 312
 313 static int srp_lookup_path(struct srp_target_port *target)
 314 {
 315         target->path.numb_path = 1;
 316
 317         init_completion(&target->done);
 318
 319         target->path_query_id = ib_sa_path_rec_get(&srp_sa_client,
 320                                                    target->srp_host->srp_dev->dev,
 321                                                    target->srp_host->port,
 322                                                    &target->path,
 323                                                    IB_SA_PATH_REC_SERVICE_ID    |
 324                                                    IB_SA_PATH_REC_DGID          |
 325                                                    IB_SA_PATH_REC_SGID          |
 326                                                    IB_SA_PATH_REC_NUMB_PATH     |
 327                                                    IB_SA_PATH_REC_PKEY,
 328                                                    SRP_PATH_REC_TIMEOUT_MS,
 329                                                    GFP_KERNEL,
 330                                                    srp_path_rec_completion,
 331                                                    target, &target->path_query);
 332         if (target->path_query_id < 0)
 333                 return target->path_query_id;
 334
 335         wait_for_completion(&target->done);
 336
 337         if (target->status < 0)
 338                 shost_printk(KERN_WARNING, target->scsi_host,
 339                              PFX "Path record query failed\n");
 340
 341         return target->status;
 342 }
 343
 344 static int srp_send_req(struct srp_target_port *target)
 345 {
 346         struct {
 347                 struct ib_cm_req_param param;
 348                 struct srp_login_req   priv;
 349         } *req = NULL;
 350         int status;
 351
 352         req = kzalloc(sizeof *req, GFP_KERNEL);
 353         if (!req)
 354                 return -ENOMEM;
 355
 356         req->param.primary_path               = &target->path;
 357         req->param.alternate_path             = NULL;
 358         req->param.service_id                 = target->service_id;
 359         req->param.qp_num                     = target->qp->qp_num;
 360         req->param.qp_type                    = target->qp->qp_type;
 361         req->param.private_data               = &req->priv;
 362         req->param.private_data_len           = sizeof req->priv;
 363         req->param.flow_control               = 1;
 364
 365         get_random_bytes(&req->param.starting_psn, 4);
 366         req->param.starting_psn              &= 0xffffff;
 367
 368         /*
 369          * Pick some arbitrary defaults here; we could make these
 370          * module parameters if anyone cared about setting them.
 371          */
 372         req->param.responder_resources        = 4;
 373         req->param.remote_cm_response_timeout = 20;
 374         req->param.local_cm_response_timeout  = 20;
 375         req->param.retry_count                = 7;
 376         req->param.rnr_retry_count            = 7;
 377         req->param.max_cm_retries             = 15;
 378
 379         req->priv.opcode        = SRP_LOGIN_REQ;
 380         req->priv.tag           = 0;
 381         req->priv.req_it_iu_len = cpu_to_be32(target->max_iu_len);
 382         req->priv.req_buf_fmt   = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
 383                                               SRP_BUF_FORMAT_INDIRECT);
 384         /*
 385          * In the published SRP specification (draft rev. 16a), the
 386          * port identifier format is 8 bytes of ID extension followed
 387          * by 8 bytes of GUID.  Older drafts put the two halves in the
 388          * opposite order, so that the GUID comes first.
 389          *
 390          * Targets conforming to these obsolete drafts can be
 391          * recognized by the I/O Class they report.
 392          */
 393         if (target->io_class == SRP_REV10_IB_IO_CLASS) {
 394                 memcpy(req->priv.initiator_port_id,
 395                        &target->path.sgid.global.interface_id, 8);
 396                 memcpy(req->priv.initiator_port_id + 8,
 397                        &target->initiator_ext, 8);
 398                 memcpy(req->priv.target_port_id,     &target->ioc_guid, 8);
 399                 memcpy(req->priv.target_port_id + 8, &target->id_ext, 8);
 400         } else {
 401                 memcpy(req->priv.initiator_port_id,
 402                        &target->initiator_ext, 8);
 403                 memcpy(req->priv.initiator_port_id + 8,
 404                        &target->path.sgid.global.interface_id, 8);
 405                 memcpy(req->priv.target_port_id,     &target->id_ext, 8);
 406                 memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
 407         }
 408
 409         /*
 410          * Topspin/Cisco SRP targets will reject our login unless we
 411          * zero out the first 8 bytes of our initiator port ID and set
 412          * the second 8 bytes to the local node GUID.
 413          */
 414         if (srp_target_is_topspin(target)) {
 415                 shost_printk(KERN_DEBUG, target->scsi_host,
 416                              PFX "Topspin/Cisco initiator port ID workaround "
 417                              "activated for target GUID %016llx\n",
 418                              (unsigned long long) be64_to_cpu(target->ioc_guid));
 419                 memset(req->priv.initiator_port_id, 0, 8);
 420                 memcpy(req->priv.initiator_port_id + 8,
 421                        &target->srp_host->srp_dev->dev->node_guid, 8);
 422         }
 423
 424         status = ib_send_cm_req(target->cm_id, &req->param);
 425
 426         kfree(req);
 427
 428         return status;
 429 }
 430
 431 static void srp_disconnect_target(struct srp_target_port *target)
 432 {
 433         /* XXX should send SRP_I_LOGOUT request */
 434
 435         init_completion(&target->done);
 436         if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
 437                 shost_printk(KERN_DEBUG, target->scsi_host,
 438                              PFX "Sending CM DREQ failed\n");
 439                 return;
 440         }
 441         wait_for_completion(&target->done);
 442 }
 443
 444 static bool srp_change_state(struct srp_target_port *target,
 445                             enum srp_target_state old,
 446                             enum srp_target_state new)
 447 {
 448         bool changed = false;
 449
 450         spin_lock_irq(&target->lock);
 451         if (target->state == old) {
 452                 target->state = new;
 453                 changed = true;
 454         }
 455         spin_unlock_irq(&target->lock);
 456         return changed;
 457 }
 458
 459 static void srp_free_req_data(struct srp_target_port *target)
 460 {
 461         struct ib_device *ibdev = target->srp_host->srp_dev->dev;
 462         struct srp_request *req;
 463         int i;
 464
 465         for (i = 0, req = target->req_ring; i < SRP_CMD_SQ_SIZE; ++i, ++req) {
 466                 kfree(req->fmr_list);
 467                 kfree(req->map_page);
 468                 if (req->indirect_dma_addr) {
 469                         ib_dma_unmap_single(ibdev, req->indirect_dma_addr,
 470                                             target->indirect_size,
 471                                             DMA_TO_DEVICE);
 472                 }
 473                 kfree(req->indirect_desc);
 474         }
 475 }
 476
 477 /**
 478  * srp_del_scsi_host_attr() - Remove attributes defined in the host template.
 479  * @shost: SCSI host whose attributes to remove from sysfs.
 480  *
 481  * Note: Any attributes defined in the host template and that did not exist
 482  * before invocation of this function will be ignored.
 483  */
 484 static void srp_del_scsi_host_attr(struct Scsi_Host *shost)
 485 {
 486         struct device_attribute **attr;
 487
 488         for (attr = shost->hostt->shost_attrs; attr && *attr; ++attr)
 489                 device_remove_file(&shost->shost_dev, *attr);
 490 }
 491
 492 static void srp_remove_work(struct work_struct *work)
 493 {
 494         struct srp_target_port *target =
 495                 container_of(work, struct srp_target_port, work);
 496
 497         if (!srp_change_state(target, SRP_TARGET_DEAD, SRP_TARGET_REMOVED))
 498                 return;
 499
 500         spin_lock(&target->srp_host->target_lock);
 501         list_del(&target->list);
 502         spin_unlock(&target->srp_host->target_lock);
 503
 504         srp_del_scsi_host_attr(target->scsi_host);
 505         srp_remove_host(target->scsi_host);
 506         scsi_remove_host(target->scsi_host);
 507         ib_destroy_cm_id(target->cm_id);
 508         srp_free_target_ib(target);
 509         srp_free_req_data(target);
 510         scsi_host_put(target->scsi_host);
 511 }
 512
 513 static int srp_connect_target(struct srp_target_port *target)
 514 {
 515         int retries = 3;
 516         int ret;
 517
 518         ret = srp_lookup_path(target);
 519         if (ret)
 520                 return ret;
 521
 522         while (1) {
 523                 init_completion(&target->done);
 524                 ret = srp_send_req(target);
 525                 if (ret)
 526                         return ret;
 527                 wait_for_completion(&target->done);
 528
 529                 /*
 530                  * The CM event handling code will set status to
 531                  * SRP_PORT_REDIRECT if we get a port redirect REJ
 532                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
 533                  * redirect REJ back.
 534                  */
 535                 switch (target->status) {
 536                 case 0:
 537                         return 0;
 538
 539                 case SRP_PORT_REDIRECT:
 540                         ret = srp_lookup_path(target);
 541                         if (ret)
 542                                 return ret;
 543                         break;
 544
 545                 case SRP_DLID_REDIRECT:
 546                         break;
 547
 548                 case SRP_STALE_CONN:
 549                         /* Our current CM id was stale, and is now in timewait.
 550                          * Try to reconnect with a new one.
 551                          */
 552                         if (!retries-- || srp_new_cm_id(target)) {
 553                                 shost_printk(KERN_ERR, target->scsi_host, PFX
 554                                              "giving up on stale connection\n");
 555                                 target->status = -ECONNRESET;
 556                                 return target->status;
 557                         }
 558
 559                         shost_printk(KERN_ERR, target->scsi_host, PFX
 560                                      "retrying stale connection\n");
 561                         break;
 562
 563                 default:
 564                         return target->status;
 565                 }
 566         }
 567 }
 568
 569 static void srp_unmap_data(struct scsi_cmnd *scmnd,
 570                            struct srp_target_port *target,
 571                            struct srp_request *req)
 572 {
 573         struct ib_device *ibdev = target->srp_host->srp_dev->dev;
 574         struct ib_pool_fmr **pfmr;
 575
 576         if (!scsi_sglist(scmnd) ||
 577             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
 578              scmnd->sc_data_direction != DMA_FROM_DEVICE))
 579                 return;
 580
 581         pfmr = req->fmr_list;
 582         while (req->nfmr--)
 583                 ib_fmr_pool_unmap(*pfmr++);
 584
 585         ib_dma_unmap_sg(ibdev, scsi_sglist(scmnd), scsi_sg_count(scmnd),
 586                         scmnd->sc_data_direction);
 587 }
 588
 589 static void srp_remove_req(struct srp_target_port *target,
 590                            struct srp_request *req, s32 req_lim_delta)
 591 {
 592         unsigned long flags;
 593
 594         srp_unmap_data(req->scmnd, target, req);
 595         spin_lock_irqsave(&target->lock, flags);
 596         target->req_lim += req_lim_delta;
 597         req->scmnd = NULL;
 598         list_add_tail(&req->list, &target->free_reqs);
 599         spin_unlock_irqrestore(&target->lock, flags);
 600 }
 601
 602 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
 603 {
 604         req->scmnd->result = DID_RESET << 16;
 605         req->scmnd->scsi_done(req->scmnd);
 606         srp_remove_req(target, req, 0);
 607 }
 608
 609 static int srp_reconnect_target(struct srp_target_port *target)
 610 {
 611         struct ib_qp_attr qp_attr;
 612         struct ib_wc wc;
 613         int i, ret;
 614
 615         if (!srp_change_state(target, SRP_TARGET_LIVE, SRP_TARGET_CONNECTING))
 616                 return -EAGAIN;
 617
 618         srp_disconnect_target(target);
 619         /*
 620          * Now get a new local CM ID so that we avoid confusing the
 621          * target in case things are really fouled up.
 622          */
 623         ret = srp_new_cm_id(target);
 624         if (ret)
 625                 goto err;
 626
 627         qp_attr.qp_state = IB_QPS_RESET;
 628         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
 629         if (ret)
 630                 goto err;
 631
 632         ret = srp_init_qp(target, target->qp);
 633         if (ret)
 634                 goto err;
 635
 636         while (ib_poll_cq(target->recv_cq, 1, &wc) > 0)
 637                 ; /* nothing */
 638         while (ib_poll_cq(target->send_cq, 1, &wc) > 0)
 639                 ; /* nothing */
 640
 641         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
 642                 struct srp_request *req = &target->req_ring[i];
 643                 if (req->scmnd)
 644                         srp_reset_req(target, req);
 645         }
 646
 647         INIT_LIST_HEAD(&target->free_tx);
 648         for (i = 0; i < SRP_SQ_SIZE; ++i)
 649                 list_add(&target->tx_ring[i]->list, &target->free_tx);
 650
 651         target->qp_in_error = 0;
 652         ret = srp_connect_target(target);
 653         if (ret)
 654                 goto err;
 655
 656         if (!srp_change_state(target, SRP_TARGET_CONNECTING, SRP_TARGET_LIVE))
 657                 ret = -EAGAIN;
 658
 659         return ret;
 660
 661 err:
 662         shost_printk(KERN_ERR, target->scsi_host,
 663                      PFX "reconnect failed (%d), removing target port.\n", ret);
 664
 665         /*
 666          * We couldn't reconnect, so kill our target port off.
 667          * However, we have to defer the real removal because we
 668          * are in the context of the SCSI error handler now, which
 669          * will deadlock if we call scsi_remove_host().
 670          *
 671          * Schedule our work inside the lock to avoid a race with
 672          * the flush_scheduled_work() in srp_remove_one().
 673          */
 674         spin_lock_irq(&target->lock);
 675         if (target->state == SRP_TARGET_CONNECTING) {
 676                 target->state = SRP_TARGET_DEAD;
 677                 INIT_WORK(&target->work, srp_remove_work);
 678                 queue_work(ib_wq, &target->work);
 679         }
 680         spin_unlock_irq(&target->lock);
 681
 682         return ret;
 683 }
 684
 685 static void srp_map_desc(struct srp_map_state *state, dma_addr_t dma_addr,
 686                          unsigned int dma_len, u32 rkey)
 687 {
 688         struct srp_direct_buf *desc = state->desc;
 689
 690         desc->va = cpu_to_be64(dma_addr);
 691         desc->key = cpu_to_be32(rkey);
 692         desc->len = cpu_to_be32(dma_len);
 693
 694         state->total_len += dma_len;
 695         state->desc++;
 696         state->ndesc++;
 697 }
 698
 699 static int srp_map_finish_fmr(struct srp_map_state *state,
 700                               struct srp_target_port *target)
 701 {
 702         struct srp_device *dev = target->srp_host->srp_dev;
 703         struct ib_pool_fmr *fmr;
 704         u64 io_addr = 0;
 705
 706         if (!state->npages)
 707                 return 0;
 708
 709         if (state->npages == 1) {
 710                 srp_map_desc(state, state->base_dma_addr, state->fmr_len,
 711                              target->rkey);
 712                 state->npages = state->fmr_len = 0;
 713                 return 0;
 714         }
 715
 716         fmr = ib_fmr_pool_map_phys(dev->fmr_pool, state->pages,
 717                                    state->npages, io_addr);
 718         if (IS_ERR(fmr))
 719                 return PTR_ERR(fmr);
 720
 721         *state->next_fmr++ = fmr;
 722         state->nfmr++;
 723
 724         srp_map_desc(state, 0, state->fmr_len, fmr->fmr->rkey);
 725         state->npages = state->fmr_len = 0;
 726         return 0;
 727 }
 728
 729 static void srp_map_update_start(struct srp_map_state *state,
 730                                  struct scatterlist *sg, int sg_index,
 731                                  dma_addr_t dma_addr)
 732 {
 733         state->unmapped_sg = sg;
 734         state->unmapped_index = sg_index;
 735         state->unmapped_addr = dma_addr;
 736 }
 737
 738 static int srp_map_sg_entry(struct srp_map_state *state,
 739                             struct srp_target_port *target,
 740                             struct scatterlist *sg, int sg_index,
 741                             int use_fmr)
 742 {
 743         struct srp_device *dev = target->srp_host->srp_dev;
 744         struct ib_device *ibdev = dev->dev;
 745         dma_addr_t dma_addr = ib_sg_dma_address(ibdev, sg);
 746         unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 747         unsigned int len;
 748         int ret;
 749
 750         if (!dma_len)
 751                 return 0;
 752
 753         if (use_fmr == SRP_MAP_NO_FMR) {
 754                 /* Once we're in direct map mode for a request, we don't
 755                  * go back to FMR mode, so no need to update anything
 756                  * other than the descriptor.
 757                  */
 758                 srp_map_desc(state, dma_addr, dma_len, target->rkey);
 759                 return 0;
 760         }
 761
 762         /* If we start at an offset into the FMR page, don't merge into
 763          * the current FMR. Finish it out, and use the kernel's MR for this
 764          * sg entry. This is to avoid potential bugs on some SRP targets
 765          * that were never quite defined, but went away when the initiator
 766          * avoided using FMR on such page fragments.
 767          */
 768         if (dma_addr & ~dev->fmr_page_mask || dma_len > dev->fmr_max_size) {
 769                 ret = srp_map_finish_fmr(state, target);
 770                 if (ret)
 771                         return ret;
 772
 773                 srp_map_desc(state, dma_addr, dma_len, target->rkey);
 774                 srp_map_update_start(state, NULL, 0, 0);
 775                 return 0;
 776         }
 777
 778         /* If this is the first sg to go into the FMR, save our position.
 779          * We need to know the first unmapped entry, its index, and the
 780          * first unmapped address within that entry to be able to restart
 781          * mapping after an error.
 782          */
 783         if (!state->unmapped_sg)
 784                 srp_map_update_start(state, sg, sg_index, dma_addr);
 785
 786         while (dma_len) {
 787                 if (state->npages == SRP_FMR_SIZE) {
 788                         ret = srp_map_finish_fmr(state, target);
 789                         if (ret)
 790                                 return ret;
 791
 792                         srp_map_update_start(state, sg, sg_index, dma_addr);
 793                 }
 794
 795                 len = min_t(unsigned int, dma_len, dev->fmr_page_size);
 796
 797                 if (!state->npages)
 798                         state->base_dma_addr = dma_addr;
 799                 state->pages[state->npages++] = dma_addr;
 800                 state->fmr_len += len;
 801                 dma_addr += len;
 802                 dma_len -= len;
 803         }
 804
 805         /* If the last entry of the FMR wasn't a full page, then we need to
 806          * close it out and start a new one -- we can only merge at page
 807          * boundries.
 808          */
 809         ret = 0;
 810         if (len != dev->fmr_page_size) {
 811                 ret = srp_map_finish_fmr(state, target);
 812                 if (!ret)
 813                         srp_map_update_start(state, NULL, 0, 0);
 814         }
 815         return ret;
 816 }
 817
 818 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
 819                         struct srp_request *req)
 820 {
 821         struct scatterlist *scat, *sg;
 822         struct srp_cmd *cmd = req->cmd->buf;
 823         int i, len, nents, count, use_fmr;
 824         struct srp_device *dev;
 825         struct ib_device *ibdev;
 826         struct srp_map_state state;
 827         struct srp_indirect_buf *indirect_hdr;
 828         u32 table_len;
 829         u8 fmt;
 830
 831         if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
 832                 return sizeof (struct srp_cmd);
 833
 834         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
 835             scmnd->sc_data_direction != DMA_TO_DEVICE) {
 836                 shost_printk(KERN_WARNING, target->scsi_host,
 837                              PFX "Unhandled data direction %d\n",
 838                              scmnd->sc_data_direction);
 839                 return -EINVAL;
 840         }
 841
 842         nents = scsi_sg_count(scmnd);
 843         scat  = scsi_sglist(scmnd);
 844
 845         dev = target->srp_host->srp_dev;
 846         ibdev = dev->dev;
 847
 848         count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
 849         if (unlikely(count == 0))
 850                 return -EIO;
 851
 852         fmt = SRP_DATA_DESC_DIRECT;
 853         len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
 854
 855         if (count == 1) {
 856                 /*
 857                  * The midlayer only generated a single gather/scatter
 858                  * entry, or DMA mapping coalesced everything to a
 859                  * single entry.  So a direct descriptor along with
 860                  * the DMA MR suffices.
 861                  */
 862                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 863
 864                 buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
 865                 buf->key = cpu_to_be32(target->rkey);
 866                 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
 867
 868                 req->nfmr = 0;
 869                 goto map_complete;
 870         }
 871
 872         /* We have more than one scatter/gather entry, so build our indirect
 873          * descriptor table, trying to merge as many entries with FMR as we
 874          * can.
 875          */
 876         indirect_hdr = (void *) cmd->add_data;
 877
 878         ib_dma_sync_single_for_cpu(ibdev, req->indirect_dma_addr,
 879                                    target->indirect_size, DMA_TO_DEVICE);
 880
 881         memset(&state, 0, sizeof(state));
 882         state.desc      = req->indirect_desc;
 883         state.pages     = req->map_page;
 884         state.next_fmr  = req->fmr_list;
 885
 886         use_fmr = dev->fmr_pool ? SRP_MAP_ALLOW_FMR : SRP_MAP_NO_FMR;
 887
 888         for_each_sg(scat, sg, count, i) {
 889                 if (srp_map_sg_entry(&state, target, sg, i, use_fmr)) {
 890                         /* FMR mapping failed, so backtrack to the first
 891                          * unmapped entry and continue on without using FMR.
 892                          */
 893                         dma_addr_t dma_addr;
 894                         unsigned int dma_len;
 895
 896 backtrack:
 897                         sg = state.unmapped_sg;
 898                         i = state.unmapped_index;
 899
 900                         dma_addr = ib_sg_dma_address(ibdev, sg);
 901                         dma_len = ib_sg_dma_len(ibdev, sg);
 902                         dma_len -= (state.unmapped_addr - dma_addr);
 903                         dma_addr = state.unmapped_addr;
 904                         use_fmr = SRP_MAP_NO_FMR;
 905                         srp_map_desc(&state, dma_addr, dma_len, target->rkey);
 906                 }
 907         }
 908
 909         if (use_fmr == SRP_MAP_ALLOW_FMR && srp_map_finish_fmr(&state, target))
 910                 goto backtrack;
 911
 912         /* We've mapped the request, now pull as much of the indirect
 913          * descriptor table as we can into the command buffer. If this
 914          * target is not using an external indirect table, we are
 915          * guaranteed to fit into the command, as the SCSI layer won't
 916          * give us more S/G entries than we allow.
 917          */
 918         req->nfmr = state.nfmr;
 919         if (state.ndesc == 1) {
 920                 /* FMR mapping was able to collapse this to one entry,
 921                  * so use a direct descriptor.
 922                  */
 923                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 924
 925                 *buf = req->indirect_desc[0];
 926                 goto map_complete;
 927         }
 928
 929         if (unlikely(target->cmd_sg_cnt < state.ndesc &&
 930                                                 !target->allow_ext_sg)) {
 931                 shost_printk(KERN_ERR, target->scsi_host,
 932                              "Could not fit S/G list into SRP_CMD\n");
 933                 return -EIO;
 934         }
 935
 936         count = min(state.ndesc, target->cmd_sg_cnt);
 937         table_len = state.ndesc * sizeof (struct srp_direct_buf);
 938
 939         fmt = SRP_DATA_DESC_INDIRECT;
 940         len = sizeof(struct srp_cmd) + sizeof (struct srp_indirect_buf);
 941         len += count * sizeof (struct srp_direct_buf);
 942
 943         memcpy(indirect_hdr->desc_list, req->indirect_desc,
 944                count * sizeof (struct srp_direct_buf));
 945
 946         indirect_hdr->table_desc.va = cpu_to_be64(req->indirect_dma_addr);
 947         indirect_hdr->table_desc.key = cpu_to_be32(target->rkey);
 948         indirect_hdr->table_desc.len = cpu_to_be32(table_len);
 949         indirect_hdr->len = cpu_to_be32(state.total_len);
 950
 951         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 952                 cmd->data_out_desc_cnt = count;
 953         else
 954                 cmd->data_in_desc_cnt = count;
 955
 956         ib_dma_sync_single_for_device(ibdev, req->indirect_dma_addr, table_len,
 957                                       DMA_TO_DEVICE);
 958
 959 map_complete:
 960         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 961                 cmd->buf_fmt = fmt << 4;
 962         else
 963                 cmd->buf_fmt = fmt;
 964
 965         return len;
 966 }
 967
 968 /*
 969  * Return an IU and possible credit to the free pool
 970  */
 971 static void srp_put_tx_iu(struct srp_target_port *target, struct srp_iu *iu,
 972                           enum srp_iu_type iu_type)
 973 {
 974         unsigned long flags;
 975
 976         spin_lock_irqsave(&target->lock, flags);
 977         list_add(&iu->list, &target->free_tx);
 978         if (iu_type != SRP_IU_RSP)
 979                 ++target->req_lim;
 980         spin_unlock_irqrestore(&target->lock, flags);
 981 }
 982
 983 /*
 984  * Must be called with target->lock held to protect req_lim and free_tx.
 985  * If IU is not sent, it must be returned using srp_put_tx_iu().
 986  *
 987  * Note:
 988  * An upper limit for the number of allocated information units for each
 989  * request type is:
 990  * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
 991  *   more than Scsi_Host.can_queue requests.
 992  * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
 993  * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
 994  *   one unanswered SRP request to an initiator.
 995  */
 996 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
 997                                       enum srp_iu_type iu_type)
 998 {
 999         s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
1000         struct srp_iu *iu;
1001
1002         srp_send_completion(target->send_cq, target);
1003
1004         if (list_empty(&target->free_tx))
1005                 return NULL;
1006
1007         /* Initiator responses to target requests do not consume credits */
1008         if (iu_type != SRP_IU_RSP) {
1009                 if (target->req_lim <= rsv) {
1010                         ++target->zero_req_lim;
1011                         return NULL;
1012                 }
1013
1014                 --target->req_lim;
1015         }
1016
1017         iu = list_first_entry(&target->free_tx, struct srp_iu, list);
1018         list_del(&iu->list);
1019         return iu;
1020 }
1021
1022 static int srp_post_send(struct srp_target_port *target,
1023                          struct srp_iu *iu, int len)
1024 {
1025         struct ib_sge list;
1026         struct ib_send_wr wr, *bad_wr;
1027
1028         list.addr   = iu->dma;
1029         list.length = len;
1030         list.lkey   = target->lkey;
1031
1032         wr.next       = NULL;
1033         wr.wr_id      = (uintptr_t) iu;
1034         wr.sg_list    = &list;
1035         wr.num_sge    = 1;
1036         wr.opcode     = IB_WR_SEND;
1037         wr.send_flags = IB_SEND_SIGNALED;
1038
1039         return ib_post_send(target->qp, &wr, &bad_wr);
1040 }
1041
1042 static int srp_post_recv(struct srp_target_port *target, struct srp_iu *iu)
1043 {
1044         struct ib_recv_wr wr, *bad_wr;
1045         struct ib_sge list;
1046
1047         list.addr   = iu->dma;
1048         list.length = iu->size;
1049         list.lkey   = target->lkey;
1050
1051         wr.next     = NULL;
1052         wr.wr_id    = (uintptr_t) iu;
1053         wr.sg_list  = &list;
1054         wr.num_sge  = 1;
1055
1056         return ib_post_recv(target->qp, &wr, &bad_wr);
1057 }
1058
1059 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
1060 {
1061         struct srp_request *req;
1062         struct scsi_cmnd *scmnd;
1063         unsigned long flags;
1064
1065         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
1066                 spin_lock_irqsave(&target->lock, flags);
1067                 target->req_lim += be32_to_cpu(rsp->req_lim_delta);
1068                 spin_unlock_irqrestore(&target->lock, flags);
1069
1070                 target->tsk_mgmt_status = -1;
1071                 if (be32_to_cpu(rsp->resp_data_len) >= 4)
1072                         target->tsk_mgmt_status = rsp->data[3];
1073                 complete(&target->tsk_mgmt_done);
1074         } else {
1075                 req = &target->req_ring[rsp->tag];
1076                 scmnd = req->scmnd;
1077                 if (!scmnd)
1078                         shost_printk(KERN_ERR, target->scsi_host,
1079                                      "Null scmnd for RSP w/tag %016llx\n",
1080                                      (unsigned long long) rsp->tag);
1081                 scmnd->result = rsp->status;
1082
1083                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
1084                         memcpy(scmnd->sense_buffer, rsp->data +
1085                                be32_to_cpu(rsp->resp_data_len),
1086                                min_t(int, be32_to_cpu(rsp->sense_data_len),
1087                                      SCSI_SENSE_BUFFERSIZE));
1088                 }
1089
1090                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
1091                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
1092                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
1093                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
1094
1095                 srp_remove_req(target, req, be32_to_cpu(rsp->req_lim_delta));
1096                 scmnd->host_scribble = NULL;
1097                 scmnd->scsi_done(scmnd);
1098         }
1099 }
1100
1101 static int srp_response_common(struct srp_target_port *target, s32 req_delta,
1102                                void *rsp, int len)
1103 {
1104         struct ib_device *dev = target->srp_host->srp_dev->dev;
1105         unsigned long flags;
1106         struct srp_iu *iu;
1107         int err;
1108
1109         spin_lock_irqsave(&target->lock, flags);
1110         target->req_lim += req_delta;
1111         iu = __srp_get_tx_iu(target, SRP_IU_RSP);
1112         spin_unlock_irqrestore(&target->lock, flags);
1113
1114         if (!iu) {
1115                 shost_printk(KERN_ERR, target->scsi_host, PFX
1116                              "no IU available to send response\n");
1117                 return 1;
1118         }
1119
1120         ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
1121         memcpy(iu->buf, rsp, len);
1122         ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
1123
1124         err = srp_post_send(target, iu, len);
1125         if (err) {
1126                 shost_printk(KERN_ERR, target->scsi_host, PFX
1127                              "unable to post response: %d\n", err);
1128                 srp_put_tx_iu(target, iu, SRP_IU_RSP);
1129         }
1130
1131         return err;
1132 }
1133
1134 static void srp_process_cred_req(struct srp_target_port *target,
1135                                  struct srp_cred_req *req)
1136 {
1137         struct srp_cred_rsp rsp = {
1138                 .opcode = SRP_CRED_RSP,
1139                 .tag = req->tag,
1140         };
1141         s32 delta = be32_to_cpu(req->req_lim_delta);
1142
1143         if (srp_response_common(target, delta, &rsp, sizeof rsp))
1144                 shost_printk(KERN_ERR, target->scsi_host, PFX
1145                              "problems processing SRP_CRED_REQ\n");
1146 }
1147
1148 static void srp_process_aer_req(struct srp_target_port *target,
1149                                 struct srp_aer_req *req)
1150 {
1151         struct srp_aer_rsp rsp = {
1152                 .opcode = SRP_AER_RSP,
1153                 .tag = req->tag,
1154         };
1155         s32 delta = be32_to_cpu(req->req_lim_delta);
1156
1157         shost_printk(KERN_ERR, target->scsi_host, PFX
1158                      "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
1159
1160         if (srp_response_common(target, delta, &rsp, sizeof rsp))
1161                 shost_printk(KERN_ERR, target->scsi_host, PFX
1162                              "problems processing SRP_AER_REQ\n");
1163 }
1164
1165 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
1166 {
1167         struct ib_device *dev = target->srp_host->srp_dev->dev;
1168         struct srp_iu *iu = (struct srp_iu *) (uintptr_t) wc->wr_id;
1169         int res;
1170         u8 opcode;
1171
1172         ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
1173                                    DMA_FROM_DEVICE);
1174
1175         opcode = *(u8 *) iu->buf;
1176
1177         if (0) {
1178                 shost_printk(KERN_ERR, target->scsi_host,
1179                              PFX "recv completion, opcode 0x%02x\n", opcode);
1180                 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
1181                                iu->buf, wc->byte_len, true);
1182         }
1183
1184         switch (opcode) {
1185         case SRP_RSP:
1186                 srp_process_rsp(target, iu->buf);
1187                 break;
1188
1189         case SRP_CRED_REQ:
1190                 srp_process_cred_req(target, iu->buf);
1191                 break;
1192
1193         case SRP_AER_REQ:
1194                 srp_process_aer_req(target, iu->buf);
1195                 break;
1196
1197         case SRP_T_LOGOUT:
1198                 /* XXX Handle target logout */
1199                 shost_printk(KERN_WARNING, target->scsi_host,
1200                              PFX "Got target logout request\n");
1201                 break;
1202
1203         default:
1204                 shost_printk(KERN_WARNING, target->scsi_host,
1205                              PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1206                 break;
1207         }
1208
1209         ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
1210                                       DMA_FROM_DEVICE);
1211
1212         res = srp_post_recv(target, iu);
1213         if (res != 0)
1214                 shost_printk(KERN_ERR, target->scsi_host,
1215                              PFX "Recv failed with error code %d\n", res);
1216 }
1217
1218 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr)
1219 {
1220         struct srp_target_port *target = target_ptr;
1221         struct ib_wc wc;
1222
1223         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1224         while (ib_poll_cq(cq, 1, &wc) > 0) {
1225                 if (wc.status) {
1226                         shost_printk(KERN_ERR, target->scsi_host,
1227                                      PFX "failed receive status %d\n",
1228                                      wc.status);
1229                         target->qp_in_error = 1;
1230                         break;
1231                 }
1232
1233                 srp_handle_recv(target, &wc);
1234         }
1235 }
1236
1237 static void srp_send_completion(struct ib_cq *cq, void *target_ptr)
1238 {
1239         struct srp_target_port *target = target_ptr;
1240         struct ib_wc wc;
1241         struct srp_iu *iu;
1242
1243         while (ib_poll_cq(cq, 1, &wc) > 0) {
1244                 if (wc.status) {
1245                         shost_printk(KERN_ERR, target->scsi_host,
1246                                      PFX "failed send status %d\n",
1247                                      wc.status);
1248                         target->qp_in_error = 1;
1249                         break;
1250                 }
1251
1252                 iu = (struct srp_iu *) (uintptr_t) wc.wr_id;
1253                 list_add(&iu->list, &target->free_tx);
1254         }
1255 }
1256
1257 static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd)
1258 {
1259         struct srp_target_port *target = host_to_target(shost);
1260         struct srp_request *req;
1261         struct srp_iu *iu;
1262         struct srp_cmd *cmd;
1263         struct ib_device *dev;
1264         unsigned long flags;
1265         int len;
1266
1267         if (target->state == SRP_TARGET_CONNECTING)
1268                 goto err;
1269
1270         if (target->state == SRP_TARGET_DEAD ||
1271             target->state == SRP_TARGET_REMOVED) {
1272                 scmnd->result = DID_BAD_TARGET << 16;
1273                 scmnd->scsi_done(scmnd);
1274                 return 0;
1275         }
1276
1277         spin_lock_irqsave(&target->lock, flags);
1278         iu = __srp_get_tx_iu(target, SRP_IU_CMD);
1279         if (!iu)
1280                 goto err_unlock;
1281
1282         req = list_first_entry(&target->free_reqs, struct srp_request, list);
1283         list_del(&req->list);
1284         spin_unlock_irqrestore(&target->lock, flags);
1285
1286         dev = target->srp_host->srp_dev->dev;
1287         ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_iu_len,
1288                                    DMA_TO_DEVICE);
1289
1290         scmnd->result        = 0;
1291         scmnd->host_scribble = (void *) req;
1292
1293         cmd = iu->buf;
1294         memset(cmd, 0, sizeof *cmd);
1295
1296         cmd->opcode = SRP_CMD;
1297         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
1298         cmd->tag    = req->index;
1299         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
1300
1301         req->scmnd    = scmnd;
1302         req->cmd      = iu;
1303
1304         len = srp_map_data(scmnd, target, req);
1305         if (len < 0) {
1306                 shost_printk(KERN_ERR, target->scsi_host,
1307                              PFX "Failed to map data\n");
1308                 goto err_iu;
1309         }
1310
1311         ib_dma_sync_single_for_device(dev, iu->dma, target->max_iu_len,
1312                                       DMA_TO_DEVICE);
1313
1314         if (srp_post_send(target, iu, len)) {
1315                 shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
1316                 goto err_unmap;
1317         }
1318
1319         return 0;
1320
1321 err_unmap:
1322         srp_unmap_data(scmnd, target, req);
1323
1324 err_iu:
1325         srp_put_tx_iu(target, iu, SRP_IU_CMD);
1326
1327         spin_lock_irqsave(&target->lock, flags);
1328         list_add(&req->list, &target->free_reqs);
1329
1330 err_unlock:
1331         spin_unlock_irqrestore(&target->lock, flags);
1332
1333 err:
1334         return SCSI_MLQUEUE_HOST_BUSY;
1335 }
1336
1337 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1338 {
1339         int i;
1340
1341         for (i = 0; i < SRP_RQ_SIZE; ++i) {
1342                 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1343                                                   target->max_ti_iu_len,
1344                                                   GFP_KERNEL, DMA_FROM_DEVICE);
1345                 if (!target->rx_ring[i])
1346                         goto err;
1347         }
1348
1349         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1350                 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1351                                                   target->max_iu_len,
1352                                                   GFP_KERNEL, DMA_TO_DEVICE);
1353                 if (!target->tx_ring[i])
1354                         goto err;
1355
1356                 list_add(&target->tx_ring[i]->list, &target->free_tx);
1357         }
1358
1359         return 0;
1360
1361 err:
1362         for (i = 0; i < SRP_RQ_SIZE; ++i) {
1363                 srp_free_iu(target->srp_host, target->rx_ring[i]);
1364                 target->rx_ring[i] = NULL;
1365         }
1366
1367         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1368                 srp_free_iu(target->srp_host, target->tx_ring[i]);
1369                 target->tx_ring[i] = NULL;
1370         }
1371
1372         return -ENOMEM;
1373 }
1374
1375 static void srp_cm_rep_handler(struct ib_cm_id *cm_id,
1376                                struct srp_login_rsp *lrsp,
1377                                struct srp_target_port *target)
1378 {
1379         struct ib_qp_attr *qp_attr = NULL;
1380         int attr_mask = 0;
1381         int ret;
1382         int i;
1383
1384         if (lrsp->opcode == SRP_LOGIN_RSP) {
1385                 target->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len);
1386                 target->req_lim       = be32_to_cpu(lrsp->req_lim_delta);
1387
1388                 /*
1389                  * Reserve credits for task management so we don't
1390                  * bounce requests back to the SCSI mid-layer.
1391                  */
1392                 target->scsi_host->can_queue
1393                         = min(target->req_lim - SRP_TSK_MGMT_SQ_SIZE,
1394                               target->scsi_host->can_queue);
1395         } else {
1396                 shost_printk(KERN_WARNING, target->scsi_host,
1397                              PFX "Unhandled RSP opcode %#x\n", lrsp->opcode);
1398                 ret = -ECONNRESET;
1399                 goto error;
1400         }
1401
1402         if (!target->rx_ring[0]) {
1403                 ret = srp_alloc_iu_bufs(target);
1404                 if (ret)
1405                         goto error;
1406         }
1407
1408         ret = -ENOMEM;
1409         qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1410         if (!qp_attr)
1411                 goto error;
1412
1413         qp_attr->qp_state = IB_QPS_RTR;
1414         ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1415         if (ret)
1416                 goto error_free;
1417
1418         ret = ib_modify_qp(target->qp, qp_attr, attr_mask);
1419         if (ret)
1420                 goto error_free;
1421
1422         for (i = 0; i < SRP_RQ_SIZE; i++) {
1423                 struct srp_iu *iu = target->rx_ring[i];
1424                 ret = srp_post_recv(target, iu);
1425                 if (ret)
1426                         goto error_free;
1427         }
1428
1429         qp_attr->qp_state = IB_QPS_RTS;
1430         ret = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1431         if (ret)
1432                 goto error_free;
1433
1434         ret = ib_modify_qp(target->qp, qp_attr, attr_mask);
1435         if (ret)
1436                 goto error_free;
1437
1438         ret = ib_send_cm_rtu(cm_id, NULL, 0);
1439
1440 error_free:
1441         kfree(qp_attr);
1442
1443 error:
1444         target->status = ret;
1445 }
1446
1447 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1448                                struct ib_cm_event *event,
1449                                struct srp_target_port *target)
1450 {
1451         struct Scsi_Host *shost = target->scsi_host;
1452         struct ib_class_port_info *cpi;
1453         int opcode;
1454
1455         switch (event->param.rej_rcvd.reason) {
1456         case IB_CM_REJ_PORT_CM_REDIRECT:
1457                 cpi = event->param.rej_rcvd.ari;
1458                 target->path.dlid = cpi->redirect_lid;
1459                 target->path.pkey = cpi->redirect_pkey;
1460                 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1461                 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1462
1463                 target->status = target->path.dlid ?
1464                         SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1465                 break;
1466
1467         case IB_CM_REJ_PORT_REDIRECT:
1468                 if (srp_target_is_topspin(target)) {
1469                         /*
1470                          * Topspin/Cisco SRP gateways incorrectly send
1471                          * reject reason code 25 when they mean 24
1472                          * (port redirect).
1473                          */
1474                         memcpy(target->path.dgid.raw,
1475                                event->param.rej_rcvd.ari, 16);
1476
1477                         shost_printk(KERN_DEBUG, shost,
1478                                      PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1479                                      (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1480                                      (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1481
1482                         target->status = SRP_PORT_REDIRECT;
1483                 } else {
1484                         shost_printk(KERN_WARNING, shost,
1485                                      "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1486                         target->status = -ECONNRESET;
1487                 }
1488                 break;
1489
1490         case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1491                 shost_printk(KERN_WARNING, shost,
1492                             "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1493                 target->status = -ECONNRESET;
1494                 break;
1495
1496         case IB_CM_REJ_CONSUMER_DEFINED:
1497                 opcode = *(u8 *) event->private_data;
1498                 if (opcode == SRP_LOGIN_REJ) {
1499                         struct srp_login_rej *rej = event->private_data;
1500                         u32 reason = be32_to_cpu(rej->reason);
1501
1502                         if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1503                                 shost_printk(KERN_WARNING, shost,
1504                                              PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1505                         else
1506                                 shost_printk(KERN_WARNING, shost,
1507                                             PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1508                 } else
1509                         shost_printk(KERN_WARNING, shost,
1510                                      "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1511                                      " opcode 0x%02x\n", opcode);
1512                 target->status = -ECONNRESET;
1513                 break;
1514
1515         case IB_CM_REJ_STALE_CONN:
1516                 shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
1517                 target->status = SRP_STALE_CONN;
1518                 break;
1519
1520         default:
1521                 shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
1522                              event->param.rej_rcvd.reason);
1523                 target->status = -ECONNRESET;
1524         }
1525 }
1526
1527 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1528 {
1529         struct srp_target_port *target = cm_id->context;
1530         int comp = 0;
1531
1532         switch (event->event) {
1533         case IB_CM_REQ_ERROR:
1534                 shost_printk(KERN_DEBUG, target->scsi_host,
1535                              PFX "Sending CM REQ failed\n");
1536                 comp = 1;
1537                 target->status = -ECONNRESET;
1538                 break;
1539
1540         case IB_CM_REP_RECEIVED:
1541                 comp = 1;
1542                 srp_cm_rep_handler(cm_id, event->private_data, target);
1543                 break;
1544
1545         case IB_CM_REJ_RECEIVED:
1546                 shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
1547                 comp = 1;
1548
1549                 srp_cm_rej_handler(cm_id, event, target);
1550                 break;
1551
1552         case IB_CM_DREQ_RECEIVED:
1553                 shost_printk(KERN_WARNING, target->scsi_host,
1554                              PFX "DREQ received - connection closed\n");
1555                 if (ib_send_cm_drep(cm_id, NULL, 0))
1556                         shost_printk(KERN_ERR, target->scsi_host,
1557                                      PFX "Sending CM DREP failed\n");
1558                 break;
1559
1560         case IB_CM_TIMEWAIT_EXIT:
1561                 shost_printk(KERN_ERR, target->scsi_host,
1562                              PFX "connection closed\n");
1563
1564                 comp = 1;
1565                 target->status = 0;
1566                 break;
1567
1568         case IB_CM_MRA_RECEIVED:
1569         case IB_CM_DREQ_ERROR:
1570         case IB_CM_DREP_RECEIVED:
1571                 break;
1572
1573         default:
1574                 shost_printk(KERN_WARNING, target->scsi_host,
1575                              PFX "Unhandled CM event %d\n", event->event);
1576                 break;
1577         }
1578
1579         if (comp)
1580                 complete(&target->done);
1581
1582         return 0;
1583 }
1584
1585 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1586                              u64 req_tag, unsigned int lun, u8 func)
1587 {
1588         struct ib_device *dev = target->srp_host->srp_dev->dev;
1589         struct srp_iu *iu;
1590         struct srp_tsk_mgmt *tsk_mgmt;
1591
1592         if (target->state == SRP_TARGET_DEAD ||
1593             target->state == SRP_TARGET_REMOVED)
1594                 return -1;
1595
1596         init_completion(&target->tsk_mgmt_done);
1597
1598         spin_lock_irq(&target->lock);
1599         iu = __srp_get_tx_iu(target, SRP_IU_TSK_MGMT);
1600         spin_unlock_irq(&target->lock);
1601
1602         if (!iu)
1603                 return -1;
1604
1605         ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
1606                                    DMA_TO_DEVICE);
1607         tsk_mgmt = iu->buf;
1608         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1609
1610         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1611         tsk_mgmt->lun           = cpu_to_be64((u64) lun << 48);
1612         tsk_mgmt->tag           = req_tag | SRP_TAG_TSK_MGMT;
1613         tsk_mgmt->tsk_mgmt_func = func;
1614         tsk_mgmt->task_tag      = req_tag;
1615
1616         ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
1617                                       DMA_TO_DEVICE);
1618         if (srp_post_send(target, iu, sizeof *tsk_mgmt)) {
1619                 srp_put_tx_iu(target, iu, SRP_IU_TSK_MGMT);
1620                 return -1;
1621         }
1622
1623         if (!wait_for_completion_timeout(&target->tsk_mgmt_done,
1624                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1625                 return -1;
1626
1627         return 0;
1628 }
1629
1630 static int srp_abort(struct scsi_cmnd *scmnd)
1631 {
1632         struct srp_target_port *target = host_to_target(scmnd->device->host);
1633         struct srp_request *req = (struct srp_request *) scmnd->host_scribble;
1634         int ret = SUCCESS;
1635
1636         shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
1637
1638         if (!req || target->qp_in_error)
1639                 return FAILED;
1640         if (srp_send_tsk_mgmt(target, req->index, scmnd->device->lun,
1641                               SRP_TSK_ABORT_TASK))
1642                 return FAILED;
1643
1644         if (req->scmnd) {
1645                 if (!target->tsk_mgmt_status) {
1646                         srp_remove_req(target, req, 0);
1647                         scmnd->result = DID_ABORT << 16;
1648                 } else
1649                         ret = FAILED;
1650         }
1651
1652         return ret;
1653 }
1654
1655 static int srp_reset_device(struct scsi_cmnd *scmnd)
1656 {
1657         struct srp_target_port *target = host_to_target(scmnd->device->host);
1658         int i;
1659
1660         shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
1661
1662         if (target->qp_in_error)
1663                 return FAILED;
1664         if (srp_send_tsk_mgmt(target, SRP_TAG_NO_REQ, scmnd->device->lun,
1665                               SRP_TSK_LUN_RESET))
1666                 return FAILED;
1667         if (target->tsk_mgmt_status)
1668                 return FAILED;
1669
1670         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
1671                 struct srp_request *req = &target->req_ring[i];
1672                 if (req->scmnd && req->scmnd->device == scmnd->device)
1673                         srp_reset_req(target, req);
1674         }
1675
1676         return SUCCESS;
1677 }
1678
1679 static int srp_reset_host(struct scsi_cmnd *scmnd)
1680 {
1681         struct srp_target_port *target = host_to_target(scmnd->device->host);
1682         int ret = FAILED;
1683
1684         shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
1685
1686         if (!srp_reconnect_target(target))
1687                 ret = SUCCESS;
1688
1689         return ret;
1690 }
1691
1692 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
1693                            char *buf)
1694 {
1695         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1696
1697         return sprintf(buf, "0x%016llx\n",
1698                        (unsigned long long) be64_to_cpu(target->id_ext));
1699 }
1700
1701 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
1702                              char *buf)
1703 {
1704         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1705
1706         return sprintf(buf, "0x%016llx\n",
1707                        (unsigned long long) be64_to_cpu(target->ioc_guid));
1708 }
1709
1710 static ssize_t show_service_id(struct device *dev,
1711                                struct device_attribute *attr, char *buf)
1712 {
1713         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1714
1715         return sprintf(buf, "0x%016llx\n",
1716                        (unsigned long long) be64_to_cpu(target->service_id));
1717 }
1718
1719 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
1720                          char *buf)
1721 {
1722         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1723
1724         return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1725 }
1726
1727 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
1728                          char *buf)
1729 {
1730         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1731
1732         return sprintf(buf, "%pI6\n", target->path.dgid.raw);
1733 }
1734
1735 static ssize_t show_orig_dgid(struct device *dev,
1736                               struct device_attribute *attr, char *buf)
1737 {
1738         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1739
1740         return sprintf(buf, "%pI6\n", target->orig_dgid);
1741 }
1742
1743 static ssize_t show_req_lim(struct device *dev,
1744                             struct device_attribute *attr, char *buf)
1745 {
1746         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1747
1748         return sprintf(buf, "%d\n", target->req_lim);
1749 }
1750
1751 static ssize_t show_zero_req_lim(struct device *dev,
1752                                  struct device_attribute *attr, char *buf)
1753 {
1754         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1755
1756         return sprintf(buf, "%d\n", target->zero_req_lim);
1757 }
1758
1759 static ssize_t show_local_ib_port(struct device *dev,
1760                                   struct device_attribute *attr, char *buf)
1761 {
1762         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1763
1764         return sprintf(buf, "%d\n", target->srp_host->port);
1765 }
1766
1767 static ssize_t show_local_ib_device(struct device *dev,
1768                                     struct device_attribute *attr, char *buf)
1769 {
1770         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1771
1772         return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
1773 }
1774
1775 static ssize_t show_cmd_sg_entries(struct device *dev,
1776                                    struct device_attribute *attr, char *buf)
1777 {
1778         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1779
1780         return sprintf(buf, "%u\n", target->cmd_sg_cnt);
1781 }
1782
1783 static ssize_t show_allow_ext_sg(struct device *dev,
1784                                  struct device_attribute *attr, char *buf)
1785 {
1786         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1787
1788         return sprintf(buf, "%s\n", target->allow_ext_sg ? "true" : "false");
1789 }
1790
1791 static DEVICE_ATTR(id_ext,          S_IRUGO, show_id_ext,          NULL);
1792 static DEVICE_ATTR(ioc_guid,        S_IRUGO, show_ioc_guid,        NULL);
1793 static DEVICE_ATTR(service_id,      S_IRUGO, show_service_id,      NULL);
1794 static DEVICE_ATTR(pkey,            S_IRUGO, show_pkey,            NULL);
1795 static DEVICE_ATTR(dgid,            S_IRUGO, show_dgid,            NULL);
1796 static DEVICE_ATTR(orig_dgid,       S_IRUGO, show_orig_dgid,       NULL);
1797 static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
1798 static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,    NULL);
1799 static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
1800 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
1801 static DEVICE_ATTR(cmd_sg_entries,  S_IRUGO, show_cmd_sg_entries,  NULL);
1802 static DEVICE_ATTR(allow_ext_sg,    S_IRUGO, show_allow_ext_sg,    NULL);
1803
1804 static struct device_attribute *srp_host_attrs[] = {
1805         &dev_attr_id_ext,
1806         &dev_attr_ioc_guid,
1807         &dev_attr_service_id,
1808         &dev_attr_pkey,
1809         &dev_attr_dgid,
1810         &dev_attr_orig_dgid,
1811         &dev_attr_req_lim,
1812         &dev_attr_zero_req_lim,
1813         &dev_attr_local_ib_port,
1814         &dev_attr_local_ib_device,
1815         &dev_attr_cmd_sg_entries,
1816         &dev_attr_allow_ext_sg,
1817         NULL
1818 };
1819
1820 static struct scsi_host_template srp_template = {
1821         .module                         = THIS_MODULE,
1822         .name                           = "InfiniBand SRP initiator",
1823         .proc_name                      = DRV_NAME,
1824         .info                           = srp_target_info,
1825         .queuecommand                   = srp_queuecommand,
1826         .eh_abort_handler               = srp_abort,
1827         .eh_device_reset_handler        = srp_reset_device,
1828         .eh_host_reset_handler          = srp_reset_host,
1829         .sg_tablesize                   = SRP_DEF_SG_TABLESIZE,
1830         .can_queue                      = SRP_CMD_SQ_SIZE,
1831         .this_id                        = -1,
1832         .cmd_per_lun                    = SRP_CMD_SQ_SIZE,
1833         .use_clustering                 = ENABLE_CLUSTERING,
1834         .shost_attrs                    = srp_host_attrs
1835 };
1836
1837 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1838 {
1839         struct srp_rport_identifiers ids;
1840         struct srp_rport *rport;
1841
1842         sprintf(target->target_name, "SRP.T10:%016llX",
1843                  (unsigned long long) be64_to_cpu(target->id_ext));
1844
1845         if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
1846                 return -ENODEV;
1847
1848         memcpy(ids.port_id, &target->id_ext, 8);
1849         memcpy(ids.port_id + 8, &target->ioc_guid, 8);
1850         ids.roles = SRP_RPORT_ROLE_TARGET;
1851         rport = srp_rport_add(target->scsi_host, &ids);
1852         if (IS_ERR(rport)) {
1853                 scsi_remove_host(target->scsi_host);
1854                 return PTR_ERR(rport);
1855         }
1856
1857         spin_lock(&host->target_lock);
1858         list_add_tail(&target->list, &host->target_list);
1859         spin_unlock(&host->target_lock);
1860
1861         target->state = SRP_TARGET_LIVE;
1862
1863         scsi_scan_target(&target->scsi_host->shost_gendev,
1864                          0, target->scsi_id, SCAN_WILD_CARD, 0);
1865
1866         return 0;
1867 }
1868
1869 static void srp_release_dev(struct device *dev)
1870 {
1871         struct srp_host *host =
1872                 container_of(dev, struct srp_host, dev);
1873
1874         complete(&host->released);
1875 }
1876
1877 static struct class srp_class = {
1878         .name    = "infiniband_srp",
1879         .dev_release = srp_release_dev
1880 };
1881
1882 /*
1883  * Target ports are added by writing
1884  *
1885  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1886  *     pkey=<P_Key>,service_id=<service ID>
1887  *
1888  * to the add_target sysfs attribute.
1889  */
1890 enum {
1891         SRP_OPT_ERR             = 0,
1892         SRP_OPT_ID_EXT          = 1 << 0,
1893         SRP_OPT_IOC_GUID        = 1 << 1,
1894         SRP_OPT_DGID            = 1 << 2,
1895         SRP_OPT_PKEY            = 1 << 3,
1896         SRP_OPT_SERVICE_ID      = 1 << 4,
1897         SRP_OPT_MAX_SECT        = 1 << 5,
1898         SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
1899         SRP_OPT_IO_CLASS        = 1 << 7,
1900         SRP_OPT_INITIATOR_EXT   = 1 << 8,
1901         SRP_OPT_CMD_SG_ENTRIES  = 1 << 9,
1902         SRP_OPT_ALLOW_EXT_SG    = 1 << 10,
1903         SRP_OPT_SG_TABLESIZE    = 1 << 11,
1904         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1905                                    SRP_OPT_IOC_GUID     |
1906                                    SRP_OPT_DGID         |
1907                                    SRP_OPT_PKEY         |
1908                                    SRP_OPT_SERVICE_ID),
1909 };
1910
1911 static const match_table_t srp_opt_tokens = {
1912         { SRP_OPT_ID_EXT,               "id_ext=%s"             },
1913         { SRP_OPT_IOC_GUID,             "ioc_guid=%s"           },
1914         { SRP_OPT_DGID,                 "dgid=%s"               },
1915         { SRP_OPT_PKEY,                 "pkey=%x"               },
1916         { SRP_OPT_SERVICE_ID,           "service_id=%s"         },
1917         { SRP_OPT_MAX_SECT,             "max_sect=%d"           },
1918         { SRP_OPT_MAX_CMD_PER_LUN,      "max_cmd_per_lun=%d"    },
1919         { SRP_OPT_IO_CLASS,             "io_class=%x"           },
1920         { SRP_OPT_INITIATOR_EXT,        "initiator_ext=%s"      },
1921         { SRP_OPT_CMD_SG_ENTRIES,       "cmd_sg_entries=%u"     },
1922         { SRP_OPT_ALLOW_EXT_SG,         "allow_ext_sg=%u"       },
1923         { SRP_OPT_SG_TABLESIZE,         "sg_tablesize=%u"       },
1924         { SRP_OPT_ERR,                  NULL                    }
1925 };
1926
1927 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1928 {
1929         char *options, *sep_opt;
1930         char *p;
1931         char dgid[3];
1932         substring_t args[MAX_OPT_ARGS];
1933         int opt_mask = 0;
1934         int token;
1935         int ret = -EINVAL;
1936         int i;
1937
1938         options = kstrdup(buf, GFP_KERNEL);
1939         if (!options)
1940                 return -ENOMEM;
1941
1942         sep_opt = options;
1943         while ((p = strsep(&sep_opt, ",")) != NULL) {
1944                 if (!*p)
1945                         continue;
1946
1947                 token = match_token(p, srp_opt_tokens, args);
1948                 opt_mask |= token;
1949
1950                 switch (token) {
1951                 case SRP_OPT_ID_EXT:
1952                         p = match_strdup(args);
1953                         if (!p) {
1954                                 ret = -ENOMEM;
1955                                 goto out;
1956                         }
1957                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1958                         kfree(p);
1959                         break;
1960
1961                 case SRP_OPT_IOC_GUID:
1962                         p = match_strdup(args);
1963                         if (!p) {
1964                                 ret = -ENOMEM;
1965                                 goto out;
1966                         }
1967                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1968                         kfree(p);
1969                         break;
1970
1971                 case SRP_OPT_DGID:
1972                         p = match_strdup(args);
1973                         if (!p) {
1974                                 ret = -ENOMEM;
1975                                 goto out;
1976                         }
1977                         if (strlen(p) != 32) {
1978                                 pr_warn("bad dest GID parameter '%s'\n", p);
1979                                 kfree(p);
1980                                 goto out;
1981                         }
1982
1983                         for (i = 0; i < 16; ++i) {
1984                                 strlcpy(dgid, p + i * 2, 3);
1985                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1986                         }
1987                         kfree(p);
1988                         memcpy(target->orig_dgid, target->path.dgid.raw, 16);
1989                         break;
1990
1991                 case SRP_OPT_PKEY:
1992                         if (match_hex(args, &token)) {
1993                                 pr_warn("bad P_Key parameter '%s'\n", p);
1994                                 goto out;
1995                         }
1996                         target->path.pkey = cpu_to_be16(token);
1997                         break;
1998
1999                 case SRP_OPT_SERVICE_ID:
2000                         p = match_strdup(args);
2001                         if (!p) {
2002                                 ret = -ENOMEM;
2003                                 goto out;
2004                         }
2005                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
2006                         target->path.service_id = target->service_id;
2007                         kfree(p);
2008                         break;
2009
2010                 case SRP_OPT_MAX_SECT:
2011                         if (match_int(args, &token)) {
2012                                 pr_warn("bad max sect parameter '%s'\n", p);
2013                                 goto out;
2014                         }
2015                         target->scsi_host->max_sectors = token;
2016                         break;
2017
2018                 case SRP_OPT_MAX_CMD_PER_LUN:
2019                         if (match_int(args, &token)) {
2020                                 pr_warn("bad max cmd_per_lun parameter '%s'\n",
2021                                         p);
2022                                 goto out;
2023                         }
2024                         target->scsi_host->cmd_per_lun = min(token, SRP_CMD_SQ_SIZE);
2025                         break;
2026
2027                 case SRP_OPT_IO_CLASS:
2028                         if (match_hex(args, &token)) {
2029                                 pr_warn("bad IO class parameter '%s'\n", p);
2030                                 goto out;
2031                         }
2032                         if (token != SRP_REV10_IB_IO_CLASS &&
2033                             token != SRP_REV16A_IB_IO_CLASS) {
2034                                 pr_warn("unknown IO class parameter value %x specified (use %x or %x).\n",
2035                                         token, SRP_REV10_IB_IO_CLASS,
2036                                         SRP_REV16A_IB_IO_CLASS);
2037                                 goto out;
2038                         }
2039                         target->io_class = token;
2040                         break;
2041
2042                 case SRP_OPT_INITIATOR_EXT:
2043                         p = match_strdup(args);
2044                         if (!p) {
2045                                 ret = -ENOMEM;
2046                                 goto out;
2047                         }
2048                         target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
2049                         kfree(p);
2050                         break;
2051
2052                 case SRP_OPT_CMD_SG_ENTRIES:
2053                         if (match_int(args, &token) || token < 1 || token > 255) {
2054                                 pr_warn("bad max cmd_sg_entries parameter '%s'\n",
2055                                         p);
2056                                 goto out;
2057                         }
2058                         target->cmd_sg_cnt = token;
2059                         break;
2060
2061                 case SRP_OPT_ALLOW_EXT_SG:
2062                         if (match_int(args, &token)) {
2063                                 pr_warn("bad allow_ext_sg parameter '%s'\n", p);
2064                                 goto out;
2065                         }
2066                         target->allow_ext_sg = !!token;
2067                         break;
2068
2069                 case SRP_OPT_SG_TABLESIZE:
2070                         if (match_int(args, &token) || token < 1 ||
2071                                         token > SCSI_MAX_SG_CHAIN_SEGMENTS) {
2072                                 pr_warn("bad max sg_tablesize parameter '%s'\n",
2073                                         p);
2074                                 goto out;
2075                         }
2076                         target->sg_tablesize = token;
2077                         break;
2078
2079                 default:
2080                         pr_warn("unknown parameter or missing value '%s' in target creation request\n",
2081                                 p);
2082                         goto out;
2083                 }
2084         }
2085
2086         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
2087                 ret = 0;
2088         else
2089                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
2090                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
2091                             !(srp_opt_tokens[i].token & opt_mask))
2092                                 pr_warn("target creation request is missing parameter '%s'\n",
2093                                         srp_opt_tokens[i].pattern);
2094
2095 out:
2096         kfree(options);
2097         return ret;
2098 }
2099
2100 static ssize_t srp_create_target(struct device *dev,
2101                                  struct device_attribute *attr,
2102                                  const char *buf, size_t count)
2103 {
2104         struct srp_host *host =
2105                 container_of(dev, struct srp_host, dev);
2106         struct Scsi_Host *target_host;
2107         struct srp_target_port *target;
2108         struct ib_device *ibdev = host->srp_dev->dev;
2109         dma_addr_t dma_addr;
2110         int i, ret;
2111
2112         target_host = scsi_host_alloc(&srp_template,
2113                                       sizeof (struct srp_target_port));
2114         if (!target_host)
2115                 return -ENOMEM;
2116
2117         target_host->transportt  = ib_srp_transport_template;
2118         target_host->max_channel = 0;
2119         target_host->max_id      = 1;
2120         target_host->max_lun     = SRP_MAX_LUN;
2121         target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
2122
2123         target = host_to_target(target_host);
2124
2125         target->io_class        = SRP_REV16A_IB_IO_CLASS;
2126         target->scsi_host       = target_host;
2127         target->srp_host        = host;
2128         target->lkey            = host->srp_dev->mr->lkey;
2129         target->rkey            = host->srp_dev->mr->rkey;
2130         target->cmd_sg_cnt      = cmd_sg_entries;
2131         target->sg_tablesize    = indirect_sg_entries ? : cmd_sg_entries;
2132         target->allow_ext_sg    = allow_ext_sg;
2133
2134         ret = srp_parse_options(buf, target);
2135         if (ret)
2136                 goto err;
2137
2138         if (!host->srp_dev->fmr_pool && !target->allow_ext_sg &&
2139                                 target->cmd_sg_cnt < target->sg_tablesize) {
2140                 pr_warn("No FMR pool and no external indirect descriptors, limiting sg_tablesize to cmd_sg_cnt\n");
2141                 target->sg_tablesize = target->cmd_sg_cnt;
2142         }
2143
2144         target_host->sg_tablesize = target->sg_tablesize;
2145         target->indirect_size = target->sg_tablesize *
2146                                 sizeof (struct srp_direct_buf);
2147         target->max_iu_len = sizeof (struct srp_cmd) +
2148                              sizeof (struct srp_indirect_buf) +
2149                              target->cmd_sg_cnt * sizeof (struct srp_direct_buf);
2150
2151         spin_lock_init(&target->lock);
2152         INIT_LIST_HEAD(&target->free_tx);
2153         INIT_LIST_HEAD(&target->free_reqs);
2154         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
2155                 struct srp_request *req = &target->req_ring[i];
2156
2157                 req->fmr_list = kmalloc(target->cmd_sg_cnt * sizeof (void *),
2158                                         GFP_KERNEL);
2159                 req->map_page = kmalloc(SRP_FMR_SIZE * sizeof (void *),
2160                                         GFP_KERNEL);
2161                 req->indirect_desc = kmalloc(target->indirect_size, GFP_KERNEL);
2162                 if (!req->fmr_list || !req->map_page || !req->indirect_desc)
2163                         goto err_free_mem;
2164
2165                 dma_addr = ib_dma_map_single(ibdev, req->indirect_desc,
2166                                              target->indirect_size,
2167                                              DMA_TO_DEVICE);
2168                 if (ib_dma_mapping_error(ibdev, dma_addr))
2169                         goto err_free_mem;
2170
2171                 req->indirect_dma_addr = dma_addr;
2172                 req->index = i;
2173                 list_add_tail(&req->list, &target->free_reqs);
2174         }
2175
2176         ib_query_gid(ibdev, host->port, 0, &target->path.sgid);
2177
2178         shost_printk(KERN_DEBUG, target->scsi_host, PFX
2179                      "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
2180                      "service_id %016llx dgid %pI6\n",
2181                (unsigned long long) be64_to_cpu(target->id_ext),
2182                (unsigned long long) be64_to_cpu(target->ioc_guid),
2183                be16_to_cpu(target->path.pkey),
2184                (unsigned long long) be64_to_cpu(target->service_id),
2185                target->path.dgid.raw);
2186
2187         ret = srp_create_target_ib(target);
2188         if (ret)
2189                 goto err_free_mem;
2190
2191         ret = srp_new_cm_id(target);
2192         if (ret)
2193                 goto err_free_ib;
2194
2195         target->qp_in_error = 0;
2196         ret = srp_connect_target(target);
2197         if (ret) {
2198                 shost_printk(KERN_ERR, target->scsi_host,
2199                              PFX "Connection failed\n");
2200                 goto err_cm_id;
2201         }
2202
2203         ret = srp_add_target(host, target);
2204         if (ret)
2205                 goto err_disconnect;
2206
2207         return count;
2208
2209 err_disconnect:
2210         srp_disconnect_target(target);
2211
2212 err_cm_id:
2213         ib_destroy_cm_id(target->cm_id);
2214
2215 err_free_ib:
2216         srp_free_target_ib(target);
2217
2218 err_free_mem:
2219         srp_free_req_data(target);
2220
2221 err:
2222         scsi_host_put(target_host);
2223
2224         return ret;
2225 }
2226
2227 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
2228
2229 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
2230                           char *buf)
2231 {
2232         struct srp_host *host = container_of(dev, struct srp_host, dev);
2233
2234         return sprintf(buf, "%s\n", host->srp_dev->dev->name);
2235 }
2236
2237 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
2238
2239 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
2240                          char *buf)
2241 {
2242         struct srp_host *host = container_of(dev, struct srp_host, dev);
2243
2244         return sprintf(buf, "%d\n", host->port);
2245 }
2246
2247 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
2248
2249 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
2250 {
2251         struct srp_host *host;
2252
2253         host = kzalloc(sizeof *host, GFP_KERNEL);
2254         if (!host)
2255                 return NULL;
2256
2257         INIT_LIST_HEAD(&host->target_list);
2258         spin_lock_init(&host->target_lock);
2259         init_completion(&host->released);
2260         host->srp_dev = device;
2261         host->port = port;
2262
2263         host->dev.class = &srp_class;
2264         host->dev.parent = device->dev->dma_device;
2265         dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
2266
2267         if (device_register(&host->dev))
2268                 goto free_host;
2269         if (device_create_file(&host->dev, &dev_attr_add_target))
2270                 goto err_class;
2271         if (device_create_file(&host->dev, &dev_attr_ibdev))
2272                 goto err_class;
2273         if (device_create_file(&host->dev, &dev_attr_port))
2274                 goto err_class;
2275
2276         return host;
2277
2278 err_class:
2279         device_unregister(&host->dev);
2280
2281 free_host:
2282         kfree(host);
2283
2284         return NULL;
2285 }
2286
2287 static void srp_add_one(struct ib_device *device)
2288 {
2289         struct srp_device *srp_dev;
2290         struct ib_device_attr *dev_attr;
2291         struct ib_fmr_pool_param fmr_param;
2292         struct srp_host *host;
2293         int max_pages_per_fmr, fmr_page_shift, s, e, p;
2294
2295         dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
2296         if (!dev_attr)
2297                 return;
2298
2299         if (ib_query_device(device, dev_attr)) {
2300                 pr_warn("Query device failed for %s\n", device->name);
2301                 goto free_attr;
2302         }
2303
2304         srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
2305         if (!srp_dev)
2306                 goto free_attr;
2307
2308         /*
2309          * Use the smallest page size supported by the HCA, down to a
2310          * minimum of 4096 bytes. We're unlikely to build large sglists
2311          * out of smaller entries.
2312          */
2313         fmr_page_shift          = max(12, ffs(dev_attr->page_size_cap) - 1);
2314         srp_dev->fmr_page_size  = 1 << fmr_page_shift;
2315         srp_dev->fmr_page_mask  = ~((u64) srp_dev->fmr_page_size - 1);
2316         srp_dev->fmr_max_size   = srp_dev->fmr_page_size * SRP_FMR_SIZE;
2317
2318         INIT_LIST_HEAD(&srp_dev->dev_list);
2319
2320         srp_dev->dev = device;
2321         srp_dev->pd  = ib_alloc_pd(device);
2322         if (IS_ERR(srp_dev->pd))
2323                 goto free_dev;
2324
2325         srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
2326                                     IB_ACCESS_LOCAL_WRITE |
2327                                     IB_ACCESS_REMOTE_READ |
2328                                     IB_ACCESS_REMOTE_WRITE);
2329         if (IS_ERR(srp_dev->mr))
2330                 goto err_pd;
2331
2332         for (max_pages_per_fmr = SRP_FMR_SIZE;
2333                         max_pages_per_fmr >= SRP_FMR_MIN_SIZE;
2334                         max_pages_per_fmr /= 2, srp_dev->fmr_max_size /= 2) {
2335                 memset(&fmr_param, 0, sizeof fmr_param);
2336                 fmr_param.pool_size         = SRP_FMR_POOL_SIZE;
2337                 fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
2338                 fmr_param.cache             = 1;
2339                 fmr_param.max_pages_per_fmr = max_pages_per_fmr;
2340                 fmr_param.page_shift        = fmr_page_shift;
2341                 fmr_param.access            = (IB_ACCESS_LOCAL_WRITE |
2342                                                IB_ACCESS_REMOTE_WRITE |
2343                                                IB_ACCESS_REMOTE_READ);
2344
2345                 srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
2346                 if (!IS_ERR(srp_dev->fmr_pool))
2347                         break;
2348         }
2349
2350         if (IS_ERR(srp_dev->fmr_pool))
2351                 srp_dev->fmr_pool = NULL;
2352
2353         if (device->node_type == RDMA_NODE_IB_SWITCH) {
2354                 s = 0;
2355                 e = 0;
2356         } else {
2357                 s = 1;
2358                 e = device->phys_port_cnt;
2359         }
2360
2361         for (p = s; p <= e; ++p) {
2362                 host = srp_add_port(srp_dev, p);
2363                 if (host)
2364                         list_add_tail(&host->list, &srp_dev->dev_list);
2365         }
2366
2367         ib_set_client_data(device, &srp_client, srp_dev);
2368
2369         goto free_attr;
2370
2371 err_pd:
2372         ib_dealloc_pd(srp_dev->pd);
2373
2374 free_dev:
2375         kfree(srp_dev);
2376
2377 free_attr:
2378         kfree(dev_attr);
2379 }
2380
2381 static void srp_remove_one(struct ib_device *device)
2382 {
2383         struct srp_device *srp_dev;
2384         struct srp_host *host, *tmp_host;
2385         LIST_HEAD(target_list);
2386         struct srp_target_port *target, *tmp_target;
2387
2388         srp_dev = ib_get_client_data(device, &srp_client);
2389
2390         list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
2391                 device_unregister(&host->dev);
2392                 /*
2393                  * Wait for the sysfs entry to go away, so that no new
2394                  * target ports can be created.
2395                  */
2396                 wait_for_completion(&host->released);
2397
2398                 /*
2399                  * Mark all target ports as removed, so we stop queueing
2400                  * commands and don't try to reconnect.
2401                  */
2402                 spin_lock(&host->target_lock);
2403                 list_for_each_entry(target, &host->target_list, list) {
2404                         spin_lock_irq(&target->lock);
2405                         target->state = SRP_TARGET_REMOVED;
2406                         spin_unlock_irq(&target->lock);
2407                 }
2408                 spin_unlock(&host->target_lock);
2409
2410                 /*
2411                  * Wait for any reconnection tasks that may have
2412                  * started before we marked our target ports as
2413                  * removed, and any target port removal tasks.
2414                  */
2415                 flush_workqueue(ib_wq);
2416
2417                 list_for_each_entry_safe(target, tmp_target,
2418                                          &host->target_list, list) {
2419                         srp_del_scsi_host_attr(target->scsi_host);
2420                         srp_remove_host(target->scsi_host);
2421                         scsi_remove_host(target->scsi_host);
2422                         srp_disconnect_target(target);
2423                         ib_destroy_cm_id(target->cm_id);
2424                         srp_free_target_ib(target);
2425                         srp_free_req_data(target);
2426                         scsi_host_put(target->scsi_host);
2427                 }
2428
2429                 kfree(host);
2430         }
2431
2432         if (srp_dev->fmr_pool)
2433                 ib_destroy_fmr_pool(srp_dev->fmr_pool);
2434         ib_dereg_mr(srp_dev->mr);
2435         ib_dealloc_pd(srp_dev->pd);
2436
2437         kfree(srp_dev);
2438 }
2439
2440 static struct srp_function_template ib_srp_transport_functions = {
2441 };
2442
2443 static int __init srp_init_module(void)
2444 {
2445         int ret;
2446
2447         BUILD_BUG_ON(FIELD_SIZEOF(struct ib_wc, wr_id) < sizeof(void *));
2448
2449         if (srp_sg_tablesize) {
2450                 pr_warn("srp_sg_tablesize is deprecated, please use cmd_sg_entries\n");
2451                 if (!cmd_sg_entries)
2452                         cmd_sg_entries = srp_sg_tablesize;
2453         }
2454
2455         if (!cmd_sg_entries)
2456                 cmd_sg_entries = SRP_DEF_SG_TABLESIZE;
2457
2458         if (cmd_sg_entries > 255) {
2459                 pr_warn("Clamping cmd_sg_entries to 255\n");
2460                 cmd_sg_entries = 255;
2461         }
2462
2463         if (!indirect_sg_entries)
2464                 indirect_sg_entries = cmd_sg_entries;
2465         else if (indirect_sg_entries < cmd_sg_entries) {
2466                 pr_warn("Bumping up indirect_sg_entries to match cmd_sg_entries (%u)\n",
2467                         cmd_sg_entries);
2468                 indirect_sg_entries = cmd_sg_entries;
2469         }
2470
2471         ib_srp_transport_template =
2472                 srp_attach_transport(&ib_srp_transport_functions);
2473         if (!ib_srp_transport_template)
2474                 return -ENOMEM;
2475
2476         ret = class_register(&srp_class);
2477         if (ret) {
2478                 pr_err("couldn't register class infiniband_srp\n");
2479                 srp_release_transport(ib_srp_transport_template);
2480                 return ret;
2481         }
2482
2483         ib_sa_register_client(&srp_sa_client);
2484
2485         ret = ib_register_client(&srp_client);
2486         if (ret) {
2487                 pr_err("couldn't register IB client\n");
2488                 srp_release_transport(ib_srp_transport_template);
2489                 ib_sa_unregister_client(&srp_sa_client);
2490                 class_unregister(&srp_class);
2491                 return ret;
2492         }
2493
2494         return 0;
2495 }
2496
2497 static void __exit srp_cleanup_module(void)
2498 {
2499         ib_unregister_client(&srp_client);
2500         ib_sa_unregister_client(&srp_sa_client);
2501         class_unregister(&srp_class);
2502         srp_release_transport(ib_srp_transport_template);
2503 }
2504
2505 module_init(srp_init_module);
2506 module_exit(srp_cleanup_module);