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 #include <linux/module.h>
  34 #include <linux/init.h>
  35 #include <linux/slab.h>
  36 #include <linux/err.h>
  37 #include <linux/string.h>
  38 #include <linux/parser.h>
  39 #include <linux/random.h>
  40 #include <linux/jiffies.h>
  41
  42 #include <asm/atomic.h>
  43
  44 #include <scsi/scsi.h>
  45 #include <scsi/scsi_device.h>
  46 #include <scsi/scsi_dbg.h>
  47 #include <scsi/srp.h>
  48 #include <scsi/scsi_transport_srp.h>
  49
  50 #include "ib_srp.h"
  51
  52 #define DRV_NAME        "ib_srp"
  53 #define PFX             DRV_NAME ": "
  54 #define DRV_VERSION     "0.2"
  55 #define DRV_RELDATE     "November 1, 2005"
  56
  57 MODULE_AUTHOR("Roland Dreier");
  58 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
  59                    "v" DRV_VERSION " (" DRV_RELDATE ")");
  60 MODULE_LICENSE("Dual BSD/GPL");
  61
  62 static int srp_sg_tablesize = SRP_DEF_SG_TABLESIZE;
  63 static int srp_max_iu_len;
  64
  65 module_param(srp_sg_tablesize, int, 0444);
  66 MODULE_PARM_DESC(srp_sg_tablesize,
  67                  "Max number of gather/scatter entries per I/O (default is 12, max 255)");
  68
  69 static int topspin_workarounds = 1;
  70
  71 module_param(topspin_workarounds, int, 0444);
  72 MODULE_PARM_DESC(topspin_workarounds,
  73                  "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
  74
  75 static int mellanox_workarounds = 1;
  76
  77 module_param(mellanox_workarounds, int, 0444);
  78 MODULE_PARM_DESC(mellanox_workarounds,
  79                  "Enable workarounds for Mellanox SRP target bugs if != 0");
  80
  81 static void srp_add_one(struct ib_device *device);
  82 static void srp_remove_one(struct ib_device *device);
  83 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);
  84 static void srp_send_completion(struct ib_cq *cq, void *target_ptr);
  85 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
  86
  87 static struct scsi_transport_template *ib_srp_transport_template;
  88
  89 static struct ib_client srp_client = {
  90         .name   = "srp",
  91         .add    = srp_add_one,
  92         .remove = srp_remove_one
  93 };
  94
  95 static struct ib_sa_client srp_sa_client;
  96
  97 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
  98 {
  99         return (struct srp_target_port *) host->hostdata;
 100 }
 101
 102 static const char *srp_target_info(struct Scsi_Host *host)
 103 {
 104         return host_to_target(host)->target_name;
 105 }
 106
 107 static int srp_target_is_topspin(struct srp_target_port *target)
 108 {
 109         static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
 110         static const u8 cisco_oui[3]   = { 0x00, 0x1b, 0x0d };
 111
 112         return topspin_workarounds &&
 113                 (!memcmp(&target->ioc_guid, topspin_oui, sizeof topspin_oui) ||
 114                  !memcmp(&target->ioc_guid, cisco_oui, sizeof cisco_oui));
 115 }
 116
 117 static int srp_target_is_mellanox(struct srp_target_port *target)
 118 {
 119         static const u8 mellanox_oui[3] = { 0x00, 0x02, 0xc9 };
 120
 121         return mellanox_workarounds &&
 122                 !memcmp(&target->ioc_guid, mellanox_oui, sizeof mellanox_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         printk(KERN_ERR PFX "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(srp_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 void srp_remove_work(struct work_struct *work)
 445 {
 446         struct srp_target_port *target =
 447                 container_of(work, struct srp_target_port, work);
 448
 449         spin_lock_irq(target->scsi_host->host_lock);
 450         if (target->state != SRP_TARGET_DEAD) {
 451                 spin_unlock_irq(target->scsi_host->host_lock);
 452                 return;
 453         }
 454         target->state = SRP_TARGET_REMOVED;
 455         spin_unlock_irq(target->scsi_host->host_lock);
 456
 457         spin_lock(&target->srp_host->target_lock);
 458         list_del(&target->list);
 459         spin_unlock(&target->srp_host->target_lock);
 460
 461         srp_remove_host(target->scsi_host);
 462         scsi_remove_host(target->scsi_host);
 463         ib_destroy_cm_id(target->cm_id);
 464         srp_free_target_ib(target);
 465         scsi_host_put(target->scsi_host);
 466 }
 467
 468 static int srp_connect_target(struct srp_target_port *target)
 469 {
 470         int retries = 3;
 471         int ret;
 472
 473         ret = srp_lookup_path(target);
 474         if (ret)
 475                 return ret;
 476
 477         while (1) {
 478                 init_completion(&target->done);
 479                 ret = srp_send_req(target);
 480                 if (ret)
 481                         return ret;
 482                 wait_for_completion(&target->done);
 483
 484                 /*
 485                  * The CM event handling code will set status to
 486                  * SRP_PORT_REDIRECT if we get a port redirect REJ
 487                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
 488                  * redirect REJ back.
 489                  */
 490                 switch (target->status) {
 491                 case 0:
 492                         return 0;
 493
 494                 case SRP_PORT_REDIRECT:
 495                         ret = srp_lookup_path(target);
 496                         if (ret)
 497                                 return ret;
 498                         break;
 499
 500                 case SRP_DLID_REDIRECT:
 501                         break;
 502
 503                 case SRP_STALE_CONN:
 504                         /* Our current CM id was stale, and is now in timewait.
 505                          * Try to reconnect with a new one.
 506                          */
 507                         if (!retries-- || srp_new_cm_id(target)) {
 508                                 shost_printk(KERN_ERR, target->scsi_host, PFX
 509                                              "giving up on stale connection\n");
 510                                 target->status = -ECONNRESET;
 511                                 return target->status;
 512                         }
 513
 514                         shost_printk(KERN_ERR, target->scsi_host, PFX
 515                                      "retrying stale connection\n");
 516                         break;
 517
 518                 default:
 519                         return target->status;
 520                 }
 521         }
 522 }
 523
 524 static void srp_unmap_data(struct scsi_cmnd *scmnd,
 525                            struct srp_target_port *target,
 526                            struct srp_request *req)
 527 {
 528         if (!scsi_sglist(scmnd) ||
 529             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
 530              scmnd->sc_data_direction != DMA_FROM_DEVICE))
 531                 return;
 532
 533         if (req->fmr) {
 534                 ib_fmr_pool_unmap(req->fmr);
 535                 req->fmr = NULL;
 536         }
 537
 538         ib_dma_unmap_sg(target->srp_host->srp_dev->dev, scsi_sglist(scmnd),
 539                         scsi_sg_count(scmnd), scmnd->sc_data_direction);
 540 }
 541
 542 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req)
 543 {
 544         srp_unmap_data(req->scmnd, target, req);
 545         list_move_tail(&req->list, &target->free_reqs);
 546 }
 547
 548 static void srp_reset_req(struct srp_target_port *target, struct srp_request *req)
 549 {
 550         req->scmnd->result = DID_RESET << 16;
 551         req->scmnd->scsi_done(req->scmnd);
 552         srp_remove_req(target, req);
 553 }
 554
 555 static int srp_reconnect_target(struct srp_target_port *target)
 556 {
 557         struct ib_qp_attr qp_attr;
 558         struct srp_request *req, *tmp;
 559         struct ib_wc wc;
 560         int ret;
 561
 562         spin_lock_irq(target->scsi_host->host_lock);
 563         if (target->state != SRP_TARGET_LIVE) {
 564                 spin_unlock_irq(target->scsi_host->host_lock);
 565                 return -EAGAIN;
 566         }
 567         target->state = SRP_TARGET_CONNECTING;
 568         spin_unlock_irq(target->scsi_host->host_lock);
 569
 570         srp_disconnect_target(target);
 571         /*
 572          * Now get a new local CM ID so that we avoid confusing the
 573          * target in case things are really fouled up.
 574          */
 575         ret = srp_new_cm_id(target);
 576         if (ret)
 577                 goto err;
 578
 579         qp_attr.qp_state = IB_QPS_RESET;
 580         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
 581         if (ret)
 582                 goto err;
 583
 584         ret = srp_init_qp(target, target->qp);
 585         if (ret)
 586                 goto err;
 587
 588         while (ib_poll_cq(target->recv_cq, 1, &wc) > 0)
 589                 ; /* nothing */
 590         while (ib_poll_cq(target->send_cq, 1, &wc) > 0)
 591                 ; /* nothing */
 592
 593         spin_lock_irq(target->scsi_host->host_lock);
 594         list_for_each_entry_safe(req, tmp, &target->req_queue, list)
 595                 srp_reset_req(target, req);
 596         spin_unlock_irq(target->scsi_host->host_lock);
 597
 598         target->rx_head  = 0;
 599         target->tx_head  = 0;
 600         target->tx_tail  = 0;
 601
 602         target->qp_in_error = 0;
 603         ret = srp_connect_target(target);
 604         if (ret)
 605                 goto err;
 606
 607         spin_lock_irq(target->scsi_host->host_lock);
 608         if (target->state == SRP_TARGET_CONNECTING) {
 609                 ret = 0;
 610                 target->state = SRP_TARGET_LIVE;
 611         } else
 612                 ret = -EAGAIN;
 613         spin_unlock_irq(target->scsi_host->host_lock);
 614
 615         return ret;
 616
 617 err:
 618         shost_printk(KERN_ERR, target->scsi_host,
 619                      PFX "reconnect failed (%d), removing target port.\n", ret);
 620
 621         /*
 622          * We couldn't reconnect, so kill our target port off.
 623          * However, we have to defer the real removal because we might
 624          * be in the context of the SCSI error handler now, which
 625          * would deadlock if we call scsi_remove_host().
 626          */
 627         spin_lock_irq(target->scsi_host->host_lock);
 628         if (target->state == SRP_TARGET_CONNECTING) {
 629                 target->state = SRP_TARGET_DEAD;
 630                 INIT_WORK(&target->work, srp_remove_work);
 631                 schedule_work(&target->work);
 632         }
 633         spin_unlock_irq(target->scsi_host->host_lock);
 634
 635         return ret;
 636 }
 637
 638 static int srp_map_fmr(struct srp_target_port *target, struct scatterlist *scat,
 639                        int sg_cnt, struct srp_request *req,
 640                        struct srp_direct_buf *buf)
 641 {
 642         u64 io_addr = 0;
 643         u64 *dma_pages;
 644         u32 len;
 645         int page_cnt;
 646         int i, j;
 647         int ret;
 648         struct srp_device *dev = target->srp_host->srp_dev;
 649         struct ib_device *ibdev = dev->dev;
 650         struct scatterlist *sg;
 651
 652         if (!dev->fmr_pool)
 653                 return -ENODEV;
 654
 655         if (srp_target_is_mellanox(target) &&
 656             (ib_sg_dma_address(ibdev, &scat[0]) & ~dev->fmr_page_mask))
 657                 return -EINVAL;
 658
 659         len = page_cnt = 0;
 660         scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
 661                 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 662
 663                 if (ib_sg_dma_address(ibdev, sg) & ~dev->fmr_page_mask) {
 664                         if (i > 0)
 665                                 return -EINVAL;
 666                         else
 667                                 ++page_cnt;
 668                 }
 669                 if ((ib_sg_dma_address(ibdev, sg) + dma_len) &
 670                     ~dev->fmr_page_mask) {
 671                         if (i < sg_cnt - 1)
 672                                 return -EINVAL;
 673                         else
 674                                 ++page_cnt;
 675                 }
 676
 677                 len += dma_len;
 678         }
 679
 680         page_cnt += len >> dev->fmr_page_shift;
 681         if (page_cnt > SRP_FMR_SIZE)
 682                 return -ENOMEM;
 683
 684         dma_pages = kmalloc(sizeof (u64) * page_cnt, GFP_ATOMIC);
 685         if (!dma_pages)
 686                 return -ENOMEM;
 687
 688         page_cnt = 0;
 689         scsi_for_each_sg(req->scmnd, sg, sg_cnt, i) {
 690                 unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 691
 692                 for (j = 0; j < dma_len; j += dev->fmr_page_size)
 693                         dma_pages[page_cnt++] =
 694                                 (ib_sg_dma_address(ibdev, sg) &
 695                                  dev->fmr_page_mask) + j;
 696         }
 697
 698         req->fmr = ib_fmr_pool_map_phys(dev->fmr_pool,
 699                                         dma_pages, page_cnt, io_addr);
 700         if (IS_ERR(req->fmr)) {
 701                 ret = PTR_ERR(req->fmr);
 702                 req->fmr = NULL;
 703                 goto out;
 704         }
 705
 706         buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, &scat[0]) &
 707                                ~dev->fmr_page_mask);
 708         buf->key = cpu_to_be32(req->fmr->fmr->rkey);
 709         buf->len = cpu_to_be32(len);
 710
 711         ret = 0;
 712
 713 out:
 714         kfree(dma_pages);
 715
 716         return ret;
 717 }
 718
 719 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
 720                         struct srp_request *req)
 721 {
 722         struct scatterlist *scat;
 723         struct srp_cmd *cmd = req->cmd->buf;
 724         int len, nents, count;
 725         u8 fmt = SRP_DATA_DESC_DIRECT;
 726         struct srp_device *dev;
 727         struct ib_device *ibdev;
 728
 729         if (!scsi_sglist(scmnd) || scmnd->sc_data_direction == DMA_NONE)
 730                 return sizeof (struct srp_cmd);
 731
 732         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
 733             scmnd->sc_data_direction != DMA_TO_DEVICE) {
 734                 shost_printk(KERN_WARNING, target->scsi_host,
 735                              PFX "Unhandled data direction %d\n",
 736                              scmnd->sc_data_direction);
 737                 return -EINVAL;
 738         }
 739
 740         nents = scsi_sg_count(scmnd);
 741         scat  = scsi_sglist(scmnd);
 742
 743         dev = target->srp_host->srp_dev;
 744         ibdev = dev->dev;
 745
 746         count = ib_dma_map_sg(ibdev, scat, nents, scmnd->sc_data_direction);
 747
 748         fmt = SRP_DATA_DESC_DIRECT;
 749         len = sizeof (struct srp_cmd) + sizeof (struct srp_direct_buf);
 750
 751         if (count == 1) {
 752                 /*
 753                  * The midlayer only generated a single gather/scatter
 754                  * entry, or DMA mapping coalesced everything to a
 755                  * single entry.  So a direct descriptor along with
 756                  * the DMA MR suffices.
 757                  */
 758                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 759
 760                 buf->va  = cpu_to_be64(ib_sg_dma_address(ibdev, scat));
 761                 buf->key = cpu_to_be32(dev->mr->rkey);
 762                 buf->len = cpu_to_be32(ib_sg_dma_len(ibdev, scat));
 763         } else if (srp_map_fmr(target, scat, count, req,
 764                                (void *) cmd->add_data)) {
 765                 /*
 766                  * FMR mapping failed, and the scatterlist has more
 767                  * than one entry.  Generate an indirect memory
 768                  * descriptor.
 769                  */
 770                 struct srp_indirect_buf *buf = (void *) cmd->add_data;
 771                 struct scatterlist *sg;
 772                 u32 datalen = 0;
 773                 int i;
 774
 775                 fmt = SRP_DATA_DESC_INDIRECT;
 776                 len = sizeof (struct srp_cmd) +
 777                         sizeof (struct srp_indirect_buf) +
 778                         count * sizeof (struct srp_direct_buf);
 779
 780                 scsi_for_each_sg(scmnd, sg, count, i) {
 781                         unsigned int dma_len = ib_sg_dma_len(ibdev, sg);
 782
 783                         buf->desc_list[i].va  =
 784                                 cpu_to_be64(ib_sg_dma_address(ibdev, sg));
 785                         buf->desc_list[i].key =
 786                                 cpu_to_be32(dev->mr->rkey);
 787                         buf->desc_list[i].len = cpu_to_be32(dma_len);
 788                         datalen += dma_len;
 789                 }
 790
 791                 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 792                         cmd->data_out_desc_cnt = count;
 793                 else
 794                         cmd->data_in_desc_cnt = count;
 795
 796                 buf->table_desc.va  =
 797                         cpu_to_be64(req->cmd->dma + sizeof *cmd + sizeof *buf);
 798                 buf->table_desc.key =
 799                         cpu_to_be32(target->srp_host->srp_dev->mr->rkey);
 800                 buf->table_desc.len =
 801                         cpu_to_be32(count * sizeof (struct srp_direct_buf));
 802
 803                 buf->len = cpu_to_be32(datalen);
 804         }
 805
 806         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 807                 cmd->buf_fmt = fmt << 4;
 808         else
 809                 cmd->buf_fmt = fmt;
 810
 811         return len;
 812 }
 813
 814 /*
 815  * Must be called with target->scsi_host->host_lock held to protect
 816  * req_lim and tx_head.  Lock cannot be dropped between call here and
 817  * call to __srp_post_send().
 818  *
 819  * Note:
 820  * An upper limit for the number of allocated information units for each
 821  * request type is:
 822  * - SRP_IU_CMD: SRP_CMD_SQ_SIZE, since the SCSI mid-layer never queues
 823  *   more than Scsi_Host.can_queue requests.
 824  * - SRP_IU_TSK_MGMT: SRP_TSK_MGMT_SQ_SIZE.
 825  * - SRP_IU_RSP: 1, since a conforming SRP target never sends more than
 826  *   one unanswered SRP request to an initiator.
 827  */
 828 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
 829                                       enum srp_iu_type iu_type)
 830 {
 831         s32 rsv = (iu_type == SRP_IU_TSK_MGMT) ? 0 : SRP_TSK_MGMT_SQ_SIZE;
 832         struct srp_iu *iu;
 833
 834         srp_send_completion(target->send_cq, target);
 835
 836         if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
 837                 return NULL;
 838
 839         /* Initiator responses to target requests do not consume credits */
 840         if (target->req_lim <= rsv && iu_type != SRP_IU_RSP) {
 841                 ++target->zero_req_lim;
 842                 return NULL;
 843         }
 844
 845         iu = target->tx_ring[target->tx_head & SRP_SQ_MASK];
 846         iu->type = iu_type;
 847         return iu;
 848 }
 849
 850 /*
 851  * Must be called with target->scsi_host->host_lock held to protect
 852  * req_lim and tx_head.
 853  */
 854 static int __srp_post_send(struct srp_target_port *target,
 855                            struct srp_iu *iu, int len)
 856 {
 857         struct ib_sge list;
 858         struct ib_send_wr wr, *bad_wr;
 859         int ret = 0;
 860
 861         list.addr   = iu->dma;
 862         list.length = len;
 863         list.lkey   = target->srp_host->srp_dev->mr->lkey;
 864
 865         wr.next       = NULL;
 866         wr.wr_id      = target->tx_head & SRP_SQ_MASK;
 867         wr.sg_list    = &list;
 868         wr.num_sge    = 1;
 869         wr.opcode     = IB_WR_SEND;
 870         wr.send_flags = IB_SEND_SIGNALED;
 871
 872         ret = ib_post_send(target->qp, &wr, &bad_wr);
 873
 874         if (!ret) {
 875                 ++target->tx_head;
 876                 if (iu->type != SRP_IU_RSP)
 877                         --target->req_lim;
 878         }
 879
 880         return ret;
 881 }
 882
 883 static int srp_post_recv(struct srp_target_port *target)
 884 {
 885         unsigned long flags;
 886         struct srp_iu *iu;
 887         struct ib_sge list;
 888         struct ib_recv_wr wr, *bad_wr;
 889         unsigned int next;
 890         int ret;
 891
 892         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 893
 894         next     = target->rx_head & SRP_RQ_MASK;
 895         wr.wr_id = next;
 896         iu       = target->rx_ring[next];
 897
 898         list.addr   = iu->dma;
 899         list.length = iu->size;
 900         list.lkey   = target->srp_host->srp_dev->mr->lkey;
 901
 902         wr.next     = NULL;
 903         wr.sg_list  = &list;
 904         wr.num_sge  = 1;
 905
 906         ret = ib_post_recv(target->qp, &wr, &bad_wr);
 907         if (!ret)
 908                 ++target->rx_head;
 909
 910         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 911
 912         return ret;
 913 }
 914
 915 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
 916 {
 917         struct srp_request *req;
 918         struct scsi_cmnd *scmnd;
 919         unsigned long flags;
 920         s32 delta;
 921
 922         delta = (s32) be32_to_cpu(rsp->req_lim_delta);
 923
 924         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 925
 926         target->req_lim += delta;
 927
 928         req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
 929
 930         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
 931                 if (be32_to_cpu(rsp->resp_data_len) < 4)
 932                         req->tsk_status = -1;
 933                 else
 934                         req->tsk_status = rsp->data[3];
 935                 complete(&req->done);
 936         } else {
 937                 scmnd = req->scmnd;
 938                 if (!scmnd)
 939                         shost_printk(KERN_ERR, target->scsi_host,
 940                                      "Null scmnd for RSP w/tag %016llx\n",
 941                                      (unsigned long long) rsp->tag);
 942                 scmnd->result = rsp->status;
 943
 944                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
 945                         memcpy(scmnd->sense_buffer, rsp->data +
 946                                be32_to_cpu(rsp->resp_data_len),
 947                                min_t(int, be32_to_cpu(rsp->sense_data_len),
 948                                      SCSI_SENSE_BUFFERSIZE));
 949                 }
 950
 951                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
 952                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
 953                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
 954                         scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
 955
 956                 if (!req->tsk_mgmt) {
 957                         scmnd->host_scribble = (void *) -1L;
 958                         scmnd->scsi_done(scmnd);
 959
 960                         srp_remove_req(target, req);
 961                 } else
 962                         req->cmd_done = 1;
 963         }
 964
 965         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 966 }
 967
 968 static int srp_response_common(struct srp_target_port *target, s32 req_delta,
 969                                void *rsp, int len)
 970 {
 971         struct ib_device *dev;
 972         unsigned long flags;
 973         struct srp_iu *iu;
 974         int err = 1;
 975
 976         dev = target->srp_host->srp_dev->dev;
 977
 978         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 979         target->req_lim += req_delta;
 980
 981         iu = __srp_get_tx_iu(target, SRP_IU_RSP);
 982         if (!iu) {
 983                 shost_printk(KERN_ERR, target->scsi_host, PFX
 984                              "no IU available to send response\n");
 985                 goto out;
 986         }
 987
 988         ib_dma_sync_single_for_cpu(dev, iu->dma, len, DMA_TO_DEVICE);
 989         memcpy(iu->buf, rsp, len);
 990         ib_dma_sync_single_for_device(dev, iu->dma, len, DMA_TO_DEVICE);
 991
 992         err = __srp_post_send(target, iu, len);
 993         if (err)
 994                 shost_printk(KERN_ERR, target->scsi_host, PFX
 995                              "unable to post response: %d\n", err);
 996
 997 out:
 998         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 999         return err;
1000 }
1001
1002 static void srp_process_cred_req(struct srp_target_port *target,
1003                                  struct srp_cred_req *req)
1004 {
1005         struct srp_cred_rsp rsp = {
1006                 .opcode = SRP_CRED_RSP,
1007                 .tag = req->tag,
1008         };
1009         s32 delta = be32_to_cpu(req->req_lim_delta);
1010
1011         if (srp_response_common(target, delta, &rsp, sizeof rsp))
1012                 shost_printk(KERN_ERR, target->scsi_host, PFX
1013                              "problems processing SRP_CRED_REQ\n");
1014 }
1015
1016 static void srp_process_aer_req(struct srp_target_port *target,
1017                                 struct srp_aer_req *req)
1018 {
1019         struct srp_aer_rsp rsp = {
1020                 .opcode = SRP_AER_RSP,
1021                 .tag = req->tag,
1022         };
1023         s32 delta = be32_to_cpu(req->req_lim_delta);
1024
1025         shost_printk(KERN_ERR, target->scsi_host, PFX
1026                      "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
1027
1028         if (srp_response_common(target, delta, &rsp, sizeof rsp))
1029                 shost_printk(KERN_ERR, target->scsi_host, PFX
1030                              "problems processing SRP_AER_REQ\n");
1031 }
1032
1033 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
1034 {
1035         struct ib_device *dev;
1036         struct srp_iu *iu;
1037         int res;
1038         u8 opcode;
1039
1040         iu = target->rx_ring[wc->wr_id];
1041
1042         dev = target->srp_host->srp_dev->dev;
1043         ib_dma_sync_single_for_cpu(dev, iu->dma, target->max_ti_iu_len,
1044                                    DMA_FROM_DEVICE);
1045
1046         opcode = *(u8 *) iu->buf;
1047
1048         if (0) {
1049                 shost_printk(KERN_ERR, target->scsi_host,
1050                              PFX "recv completion, opcode 0x%02x\n", opcode);
1051                 print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 8, 1,
1052                                iu->buf, wc->byte_len, true);
1053         }
1054
1055         switch (opcode) {
1056         case SRP_RSP:
1057                 srp_process_rsp(target, iu->buf);
1058                 break;
1059
1060         case SRP_CRED_REQ:
1061                 srp_process_cred_req(target, iu->buf);
1062                 break;
1063
1064         case SRP_AER_REQ:
1065                 srp_process_aer_req(target, iu->buf);
1066                 break;
1067
1068         case SRP_T_LOGOUT:
1069                 /* XXX Handle target logout */
1070                 shost_printk(KERN_WARNING, target->scsi_host,
1071                              PFX "Got target logout request\n");
1072                 break;
1073
1074         default:
1075                 shost_printk(KERN_WARNING, target->scsi_host,
1076                              PFX "Unhandled SRP opcode 0x%02x\n", opcode);
1077                 break;
1078         }
1079
1080         ib_dma_sync_single_for_device(dev, iu->dma, target->max_ti_iu_len,
1081                                       DMA_FROM_DEVICE);
1082
1083         res = srp_post_recv(target);
1084         if (res != 0)
1085                 shost_printk(KERN_ERR, target->scsi_host,
1086                              PFX "Recv failed with error code %d\n", res);
1087 }
1088
1089 static void srp_recv_completion(struct ib_cq *cq, void *target_ptr)
1090 {
1091         struct srp_target_port *target = target_ptr;
1092         struct ib_wc wc;
1093
1094         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
1095         while (ib_poll_cq(cq, 1, &wc) > 0) {
1096                 if (wc.status) {
1097                         shost_printk(KERN_ERR, target->scsi_host,
1098                                      PFX "failed receive status %d\n",
1099                                      wc.status);
1100                         target->qp_in_error = 1;
1101                         break;
1102                 }
1103
1104                 srp_handle_recv(target, &wc);
1105         }
1106 }
1107
1108 static void srp_send_completion(struct ib_cq *cq, void *target_ptr)
1109 {
1110         struct srp_target_port *target = target_ptr;
1111         struct ib_wc wc;
1112
1113         while (ib_poll_cq(cq, 1, &wc) > 0) {
1114                 if (wc.status) {
1115                         shost_printk(KERN_ERR, target->scsi_host,
1116                                      PFX "failed send status %d\n",
1117                                      wc.status);
1118                         target->qp_in_error = 1;
1119                         break;
1120                 }
1121
1122                 ++target->tx_tail;
1123         }
1124 }
1125
1126 static int srp_queuecommand(struct scsi_cmnd *scmnd,
1127                             void (*done)(struct scsi_cmnd *))
1128 {
1129         struct srp_target_port *target = host_to_target(scmnd->device->host);
1130         struct srp_request *req;
1131         struct srp_iu *iu;
1132         struct srp_cmd *cmd;
1133         struct ib_device *dev;
1134         int len;
1135
1136         if (target->state == SRP_TARGET_CONNECTING)
1137                 goto err;
1138
1139         if (target->state == SRP_TARGET_DEAD ||
1140             target->state == SRP_TARGET_REMOVED) {
1141                 scmnd->result = DID_BAD_TARGET << 16;
1142                 done(scmnd);
1143                 return 0;
1144         }
1145
1146         iu = __srp_get_tx_iu(target, SRP_IU_CMD);
1147         if (!iu)
1148                 goto err;
1149
1150         dev = target->srp_host->srp_dev->dev;
1151         ib_dma_sync_single_for_cpu(dev, iu->dma, srp_max_iu_len,
1152                                    DMA_TO_DEVICE);
1153
1154         req = list_first_entry(&target->free_reqs, struct srp_request, list);
1155
1156         scmnd->scsi_done     = done;
1157         scmnd->result        = 0;
1158         scmnd->host_scribble = (void *) (long) req->index;
1159
1160         cmd = iu->buf;
1161         memset(cmd, 0, sizeof *cmd);
1162
1163         cmd->opcode = SRP_CMD;
1164         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
1165         cmd->tag    = req->index;
1166         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
1167
1168         req->scmnd    = scmnd;
1169         req->cmd      = iu;
1170         req->cmd_done = 0;
1171         req->tsk_mgmt = NULL;
1172
1173         len = srp_map_data(scmnd, target, req);
1174         if (len < 0) {
1175                 shost_printk(KERN_ERR, target->scsi_host,
1176                              PFX "Failed to map data\n");
1177                 goto err;
1178         }
1179
1180         ib_dma_sync_single_for_device(dev, iu->dma, srp_max_iu_len,
1181                                       DMA_TO_DEVICE);
1182
1183         if (__srp_post_send(target, iu, len)) {
1184                 shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
1185                 goto err_unmap;
1186         }
1187
1188         list_move_tail(&req->list, &target->req_queue);
1189
1190         return 0;
1191
1192 err_unmap:
1193         srp_unmap_data(scmnd, target, req);
1194
1195 err:
1196         return SCSI_MLQUEUE_HOST_BUSY;
1197 }
1198
1199 static int srp_alloc_iu_bufs(struct srp_target_port *target)
1200 {
1201         int i;
1202
1203         for (i = 0; i < SRP_RQ_SIZE; ++i) {
1204                 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
1205                                                   target->max_ti_iu_len,
1206                                                   GFP_KERNEL, DMA_FROM_DEVICE);
1207                 if (!target->rx_ring[i])
1208                         goto err;
1209         }
1210
1211         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1212                 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
1213                                                   srp_max_iu_len,
1214                                                   GFP_KERNEL, DMA_TO_DEVICE);
1215                 if (!target->tx_ring[i])
1216                         goto err;
1217         }
1218
1219         return 0;
1220
1221 err:
1222         for (i = 0; i < SRP_RQ_SIZE; ++i) {
1223                 srp_free_iu(target->srp_host, target->rx_ring[i]);
1224                 target->rx_ring[i] = NULL;
1225         }
1226
1227         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1228                 srp_free_iu(target->srp_host, target->tx_ring[i]);
1229                 target->tx_ring[i] = NULL;
1230         }
1231
1232         return -ENOMEM;
1233 }
1234
1235 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
1236                                struct ib_cm_event *event,
1237                                struct srp_target_port *target)
1238 {
1239         struct Scsi_Host *shost = target->scsi_host;
1240         struct ib_class_port_info *cpi;
1241         int opcode;
1242
1243         switch (event->param.rej_rcvd.reason) {
1244         case IB_CM_REJ_PORT_CM_REDIRECT:
1245                 cpi = event->param.rej_rcvd.ari;
1246                 target->path.dlid = cpi->redirect_lid;
1247                 target->path.pkey = cpi->redirect_pkey;
1248                 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
1249                 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
1250
1251                 target->status = target->path.dlid ?
1252                         SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
1253                 break;
1254
1255         case IB_CM_REJ_PORT_REDIRECT:
1256                 if (srp_target_is_topspin(target)) {
1257                         /*
1258                          * Topspin/Cisco SRP gateways incorrectly send
1259                          * reject reason code 25 when they mean 24
1260                          * (port redirect).
1261                          */
1262                         memcpy(target->path.dgid.raw,
1263                                event->param.rej_rcvd.ari, 16);
1264
1265                         shost_printk(KERN_DEBUG, shost,
1266                                      PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1267                                      (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1268                                      (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1269
1270                         target->status = SRP_PORT_REDIRECT;
1271                 } else {
1272                         shost_printk(KERN_WARNING, shost,
1273                                      "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1274                         target->status = -ECONNRESET;
1275                 }
1276                 break;
1277
1278         case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1279                 shost_printk(KERN_WARNING, shost,
1280                             "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1281                 target->status = -ECONNRESET;
1282                 break;
1283
1284         case IB_CM_REJ_CONSUMER_DEFINED:
1285                 opcode = *(u8 *) event->private_data;
1286                 if (opcode == SRP_LOGIN_REJ) {
1287                         struct srp_login_rej *rej = event->private_data;
1288                         u32 reason = be32_to_cpu(rej->reason);
1289
1290                         if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1291                                 shost_printk(KERN_WARNING, shost,
1292                                              PFX "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1293                         else
1294                                 shost_printk(KERN_WARNING, shost,
1295                                             PFX "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1296                 } else
1297                         shost_printk(KERN_WARNING, shost,
1298                                      "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1299                                      " opcode 0x%02x\n", opcode);
1300                 target->status = -ECONNRESET;
1301                 break;
1302
1303         case IB_CM_REJ_STALE_CONN:
1304                 shost_printk(KERN_WARNING, shost, "  REJ reason: stale connection\n");
1305                 target->status = SRP_STALE_CONN;
1306                 break;
1307
1308         default:
1309                 shost_printk(KERN_WARNING, shost, "  REJ reason 0x%x\n",
1310                              event->param.rej_rcvd.reason);
1311                 target->status = -ECONNRESET;
1312         }
1313 }
1314
1315 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1316 {
1317         struct srp_target_port *target = cm_id->context;
1318         struct ib_qp_attr *qp_attr = NULL;
1319         int attr_mask = 0;
1320         int comp = 0;
1321         int opcode = 0;
1322         int i;
1323
1324         switch (event->event) {
1325         case IB_CM_REQ_ERROR:
1326                 shost_printk(KERN_DEBUG, target->scsi_host,
1327                              PFX "Sending CM REQ failed\n");
1328                 comp = 1;
1329                 target->status = -ECONNRESET;
1330                 break;
1331
1332         case IB_CM_REP_RECEIVED:
1333                 comp = 1;
1334                 opcode = *(u8 *) event->private_data;
1335
1336                 if (opcode == SRP_LOGIN_RSP) {
1337                         struct srp_login_rsp *rsp = event->private_data;
1338
1339                         target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1340                         target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1341
1342                         /*
1343                          * Reserve credits for task management so we don't
1344                          * bounce requests back to the SCSI mid-layer.
1345                          */
1346                         target->scsi_host->can_queue
1347                                 = min(target->req_lim - SRP_TSK_MGMT_SQ_SIZE,
1348                                       target->scsi_host->can_queue);
1349                 } else {
1350                         shost_printk(KERN_WARNING, target->scsi_host,
1351                                     PFX "Unhandled RSP opcode %#x\n", opcode);
1352                         target->status = -ECONNRESET;
1353                         break;
1354                 }
1355
1356                 if (!target->rx_ring[0]) {
1357                         target->status = srp_alloc_iu_bufs(target);
1358                         if (target->status)
1359                                 break;
1360                 }
1361
1362                 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1363                 if (!qp_attr) {
1364                         target->status = -ENOMEM;
1365                         break;
1366                 }
1367
1368                 qp_attr->qp_state = IB_QPS_RTR;
1369                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1370                 if (target->status)
1371                         break;
1372
1373                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1374                 if (target->status)
1375                         break;
1376
1377                 for (i = 0; i < SRP_RQ_SIZE; i++) {
1378                         target->status = srp_post_recv(target);
1379                         if (target->status)
1380                                 break;
1381                 }
1382                 if (target->status)
1383                         break;
1384
1385                 qp_attr->qp_state = IB_QPS_RTS;
1386                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1387                 if (target->status)
1388                         break;
1389
1390                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1391                 if (target->status)
1392                         break;
1393
1394                 target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1395                 if (target->status)
1396                         break;
1397
1398                 break;
1399
1400         case IB_CM_REJ_RECEIVED:
1401                 shost_printk(KERN_DEBUG, target->scsi_host, PFX "REJ received\n");
1402                 comp = 1;
1403
1404                 srp_cm_rej_handler(cm_id, event, target);
1405                 break;
1406
1407         case IB_CM_DREQ_RECEIVED:
1408                 shost_printk(KERN_WARNING, target->scsi_host,
1409                              PFX "DREQ received - connection closed\n");
1410                 if (ib_send_cm_drep(cm_id, NULL, 0))
1411                         shost_printk(KERN_ERR, target->scsi_host,
1412                                      PFX "Sending CM DREP failed\n");
1413                 break;
1414
1415         case IB_CM_TIMEWAIT_EXIT:
1416                 shost_printk(KERN_ERR, target->scsi_host,
1417                              PFX "connection closed\n");
1418
1419                 comp = 1;
1420                 target->status = 0;
1421                 break;
1422
1423         case IB_CM_MRA_RECEIVED:
1424         case IB_CM_DREQ_ERROR:
1425         case IB_CM_DREP_RECEIVED:
1426                 break;
1427
1428         default:
1429                 shost_printk(KERN_WARNING, target->scsi_host,
1430                              PFX "Unhandled CM event %d\n", event->event);
1431                 break;
1432         }
1433
1434         if (comp)
1435                 complete(&target->done);
1436
1437         kfree(qp_attr);
1438
1439         return 0;
1440 }
1441
1442 static int srp_send_tsk_mgmt(struct srp_target_port *target,
1443                              struct srp_request *req, u8 func)
1444 {
1445         struct ib_device *dev = target->srp_host->srp_dev->dev;
1446         struct srp_iu *iu;
1447         struct srp_tsk_mgmt *tsk_mgmt;
1448
1449         spin_lock_irq(target->scsi_host->host_lock);
1450
1451         if (target->state == SRP_TARGET_DEAD ||
1452             target->state == SRP_TARGET_REMOVED) {
1453                 req->scmnd->result = DID_BAD_TARGET << 16;
1454                 goto out;
1455         }
1456
1457         init_completion(&req->done);
1458
1459         iu = __srp_get_tx_iu(target, SRP_IU_TSK_MGMT);
1460         if (!iu)
1461                 goto out;
1462
1463         ib_dma_sync_single_for_cpu(dev, iu->dma, sizeof *tsk_mgmt,
1464                                    DMA_TO_DEVICE);
1465         tsk_mgmt = iu->buf;
1466         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1467
1468         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1469         tsk_mgmt->lun           = cpu_to_be64((u64) req->scmnd->device->lun << 48);
1470         tsk_mgmt->tag           = req->index | SRP_TAG_TSK_MGMT;
1471         tsk_mgmt->tsk_mgmt_func = func;
1472         tsk_mgmt->task_tag      = req->index;
1473
1474         ib_dma_sync_single_for_device(dev, iu->dma, sizeof *tsk_mgmt,
1475                                       DMA_TO_DEVICE);
1476         if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1477                 goto out;
1478
1479         req->tsk_mgmt = iu;
1480
1481         spin_unlock_irq(target->scsi_host->host_lock);
1482
1483         if (!wait_for_completion_timeout(&req->done,
1484                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1485                 return -1;
1486
1487         return 0;
1488
1489 out:
1490         spin_unlock_irq(target->scsi_host->host_lock);
1491         return -1;
1492 }
1493
1494 static int srp_find_req(struct srp_target_port *target,
1495                         struct scsi_cmnd *scmnd,
1496                         struct srp_request **req)
1497 {
1498         if (scmnd->host_scribble == (void *) -1L)
1499                 return -1;
1500
1501         *req = &target->req_ring[(long) scmnd->host_scribble];
1502
1503         return 0;
1504 }
1505
1506 static int srp_abort(struct scsi_cmnd *scmnd)
1507 {
1508         struct srp_target_port *target = host_to_target(scmnd->device->host);
1509         struct srp_request *req;
1510         int ret = SUCCESS;
1511
1512         shost_printk(KERN_ERR, target->scsi_host, "SRP abort called\n");
1513
1514         if (target->qp_in_error)
1515                 return FAILED;
1516         if (srp_find_req(target, scmnd, &req))
1517                 return FAILED;
1518         if (srp_send_tsk_mgmt(target, req, SRP_TSK_ABORT_TASK))
1519                 return FAILED;
1520
1521         spin_lock_irq(target->scsi_host->host_lock);
1522
1523         if (req->cmd_done) {
1524                 srp_remove_req(target, req);
1525                 scmnd->scsi_done(scmnd);
1526         } else if (!req->tsk_status) {
1527                 srp_remove_req(target, req);
1528                 scmnd->result = DID_ABORT << 16;
1529         } else
1530                 ret = FAILED;
1531
1532         spin_unlock_irq(target->scsi_host->host_lock);
1533
1534         return ret;
1535 }
1536
1537 static int srp_reset_device(struct scsi_cmnd *scmnd)
1538 {
1539         struct srp_target_port *target = host_to_target(scmnd->device->host);
1540         struct srp_request *req, *tmp;
1541
1542         shost_printk(KERN_ERR, target->scsi_host, "SRP reset_device called\n");
1543
1544         if (target->qp_in_error)
1545                 return FAILED;
1546         if (srp_find_req(target, scmnd, &req))
1547                 return FAILED;
1548         if (srp_send_tsk_mgmt(target, req, SRP_TSK_LUN_RESET))
1549                 return FAILED;
1550         if (req->tsk_status)
1551                 return FAILED;
1552
1553         spin_lock_irq(target->scsi_host->host_lock);
1554
1555         list_for_each_entry_safe(req, tmp, &target->req_queue, list)
1556                 if (req->scmnd->device == scmnd->device)
1557                         srp_reset_req(target, req);
1558
1559         spin_unlock_irq(target->scsi_host->host_lock);
1560
1561         return SUCCESS;
1562 }
1563
1564 static int srp_reset_host(struct scsi_cmnd *scmnd)
1565 {
1566         struct srp_target_port *target = host_to_target(scmnd->device->host);
1567         int ret = FAILED;
1568
1569         shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host called\n");
1570
1571         if (!srp_reconnect_target(target))
1572                 ret = SUCCESS;
1573
1574         return ret;
1575 }
1576
1577 static ssize_t show_id_ext(struct device *dev, struct device_attribute *attr,
1578                            char *buf)
1579 {
1580         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1581
1582         if (target->state == SRP_TARGET_DEAD ||
1583             target->state == SRP_TARGET_REMOVED)
1584                 return -ENODEV;
1585
1586         return sprintf(buf, "0x%016llx\n",
1587                        (unsigned long long) be64_to_cpu(target->id_ext));
1588 }
1589
1590 static ssize_t show_ioc_guid(struct device *dev, struct device_attribute *attr,
1591                              char *buf)
1592 {
1593         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1594
1595         if (target->state == SRP_TARGET_DEAD ||
1596             target->state == SRP_TARGET_REMOVED)
1597                 return -ENODEV;
1598
1599         return sprintf(buf, "0x%016llx\n",
1600                        (unsigned long long) be64_to_cpu(target->ioc_guid));
1601 }
1602
1603 static ssize_t show_service_id(struct device *dev,
1604                                struct device_attribute *attr, char *buf)
1605 {
1606         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1607
1608         if (target->state == SRP_TARGET_DEAD ||
1609             target->state == SRP_TARGET_REMOVED)
1610                 return -ENODEV;
1611
1612         return sprintf(buf, "0x%016llx\n",
1613                        (unsigned long long) be64_to_cpu(target->service_id));
1614 }
1615
1616 static ssize_t show_pkey(struct device *dev, struct device_attribute *attr,
1617                          char *buf)
1618 {
1619         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1620
1621         if (target->state == SRP_TARGET_DEAD ||
1622             target->state == SRP_TARGET_REMOVED)
1623                 return -ENODEV;
1624
1625         return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1626 }
1627
1628 static ssize_t show_dgid(struct device *dev, struct device_attribute *attr,
1629                          char *buf)
1630 {
1631         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1632
1633         if (target->state == SRP_TARGET_DEAD ||
1634             target->state == SRP_TARGET_REMOVED)
1635                 return -ENODEV;
1636
1637         return sprintf(buf, "%pI6\n", target->path.dgid.raw);
1638 }
1639
1640 static ssize_t show_orig_dgid(struct device *dev,
1641                               struct device_attribute *attr, char *buf)
1642 {
1643         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1644
1645         if (target->state == SRP_TARGET_DEAD ||
1646             target->state == SRP_TARGET_REMOVED)
1647                 return -ENODEV;
1648
1649         return sprintf(buf, "%pI6\n", target->orig_dgid);
1650 }
1651
1652 static ssize_t show_req_lim(struct device *dev,
1653                             struct device_attribute *attr, char *buf)
1654 {
1655         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1656
1657         if (target->state == SRP_TARGET_DEAD ||
1658             target->state == SRP_TARGET_REMOVED)
1659                 return -ENODEV;
1660
1661         return sprintf(buf, "%d\n", target->req_lim);
1662 }
1663
1664 static ssize_t show_zero_req_lim(struct device *dev,
1665                                  struct device_attribute *attr, char *buf)
1666 {
1667         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1668
1669         if (target->state == SRP_TARGET_DEAD ||
1670             target->state == SRP_TARGET_REMOVED)
1671                 return -ENODEV;
1672
1673         return sprintf(buf, "%d\n", target->zero_req_lim);
1674 }
1675
1676 static ssize_t show_local_ib_port(struct device *dev,
1677                                   struct device_attribute *attr, char *buf)
1678 {
1679         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1680
1681         return sprintf(buf, "%d\n", target->srp_host->port);
1682 }
1683
1684 static ssize_t show_local_ib_device(struct device *dev,
1685                                     struct device_attribute *attr, char *buf)
1686 {
1687         struct srp_target_port *target = host_to_target(class_to_shost(dev));
1688
1689         return sprintf(buf, "%s\n", target->srp_host->srp_dev->dev->name);
1690 }
1691
1692 static DEVICE_ATTR(id_ext,          S_IRUGO, show_id_ext,          NULL);
1693 static DEVICE_ATTR(ioc_guid,        S_IRUGO, show_ioc_guid,        NULL);
1694 static DEVICE_ATTR(service_id,      S_IRUGO, show_service_id,      NULL);
1695 static DEVICE_ATTR(pkey,            S_IRUGO, show_pkey,            NULL);
1696 static DEVICE_ATTR(dgid,            S_IRUGO, show_dgid,            NULL);
1697 static DEVICE_ATTR(orig_dgid,       S_IRUGO, show_orig_dgid,       NULL);
1698 static DEVICE_ATTR(req_lim,         S_IRUGO, show_req_lim,         NULL);
1699 static DEVICE_ATTR(zero_req_lim,    S_IRUGO, show_zero_req_lim,    NULL);
1700 static DEVICE_ATTR(local_ib_port,   S_IRUGO, show_local_ib_port,   NULL);
1701 static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL);
1702
1703 static struct device_attribute *srp_host_attrs[] = {
1704         &dev_attr_id_ext,
1705         &dev_attr_ioc_guid,
1706         &dev_attr_service_id,
1707         &dev_attr_pkey,
1708         &dev_attr_dgid,
1709         &dev_attr_orig_dgid,
1710         &dev_attr_req_lim,
1711         &dev_attr_zero_req_lim,
1712         &dev_attr_local_ib_port,
1713         &dev_attr_local_ib_device,
1714         NULL
1715 };
1716
1717 static struct scsi_host_template srp_template = {
1718         .module                         = THIS_MODULE,
1719         .name                           = "InfiniBand SRP initiator",
1720         .proc_name                      = DRV_NAME,
1721         .info                           = srp_target_info,
1722         .queuecommand                   = srp_queuecommand,
1723         .eh_abort_handler               = srp_abort,
1724         .eh_device_reset_handler        = srp_reset_device,
1725         .eh_host_reset_handler          = srp_reset_host,
1726         .can_queue                      = SRP_CMD_SQ_SIZE,
1727         .this_id                        = -1,
1728         .cmd_per_lun                    = SRP_CMD_SQ_SIZE,
1729         .use_clustering                 = ENABLE_CLUSTERING,
1730         .shost_attrs                    = srp_host_attrs
1731 };
1732
1733 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1734 {
1735         struct srp_rport_identifiers ids;
1736         struct srp_rport *rport;
1737
1738         sprintf(target->target_name, "SRP.T10:%016llX",
1739                  (unsigned long long) be64_to_cpu(target->id_ext));
1740
1741         if (scsi_add_host(target->scsi_host, host->srp_dev->dev->dma_device))
1742                 return -ENODEV;
1743
1744         memcpy(ids.port_id, &target->id_ext, 8);
1745         memcpy(ids.port_id + 8, &target->ioc_guid, 8);
1746         ids.roles = SRP_RPORT_ROLE_TARGET;
1747         rport = srp_rport_add(target->scsi_host, &ids);
1748         if (IS_ERR(rport)) {
1749                 scsi_remove_host(target->scsi_host);
1750                 return PTR_ERR(rport);
1751         }
1752
1753         spin_lock(&host->target_lock);
1754         list_add_tail(&target->list, &host->target_list);
1755         spin_unlock(&host->target_lock);
1756
1757         target->state = SRP_TARGET_LIVE;
1758
1759         scsi_scan_target(&target->scsi_host->shost_gendev,
1760                          0, target->scsi_id, SCAN_WILD_CARD, 0);
1761
1762         return 0;
1763 }
1764
1765 static void srp_release_dev(struct device *dev)
1766 {
1767         struct srp_host *host =
1768                 container_of(dev, struct srp_host, dev);
1769
1770         complete(&host->released);
1771 }
1772
1773 static struct class srp_class = {
1774         .name    = "infiniband_srp",
1775         .dev_release = srp_release_dev
1776 };
1777
1778 /*
1779  * Target ports are added by writing
1780  *
1781  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1782  *     pkey=<P_Key>,service_id=<service ID>
1783  *
1784  * to the add_target sysfs attribute.
1785  */
1786 enum {
1787         SRP_OPT_ERR             = 0,
1788         SRP_OPT_ID_EXT          = 1 << 0,
1789         SRP_OPT_IOC_GUID        = 1 << 1,
1790         SRP_OPT_DGID            = 1 << 2,
1791         SRP_OPT_PKEY            = 1 << 3,
1792         SRP_OPT_SERVICE_ID      = 1 << 4,
1793         SRP_OPT_MAX_SECT        = 1 << 5,
1794         SRP_OPT_MAX_CMD_PER_LUN = 1 << 6,
1795         SRP_OPT_IO_CLASS        = 1 << 7,
1796         SRP_OPT_INITIATOR_EXT   = 1 << 8,
1797         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1798                                    SRP_OPT_IOC_GUID     |
1799                                    SRP_OPT_DGID         |
1800                                    SRP_OPT_PKEY         |
1801                                    SRP_OPT_SERVICE_ID),
1802 };
1803
1804 static const match_table_t srp_opt_tokens = {
1805         { SRP_OPT_ID_EXT,               "id_ext=%s"             },
1806         { SRP_OPT_IOC_GUID,             "ioc_guid=%s"           },
1807         { SRP_OPT_DGID,                 "dgid=%s"               },
1808         { SRP_OPT_PKEY,                 "pkey=%x"               },
1809         { SRP_OPT_SERVICE_ID,           "service_id=%s"         },
1810         { SRP_OPT_MAX_SECT,             "max_sect=%d"           },
1811         { SRP_OPT_MAX_CMD_PER_LUN,      "max_cmd_per_lun=%d"    },
1812         { SRP_OPT_IO_CLASS,             "io_class=%x"           },
1813         { SRP_OPT_INITIATOR_EXT,        "initiator_ext=%s"      },
1814         { SRP_OPT_ERR,                  NULL                    }
1815 };
1816
1817 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1818 {
1819         char *options, *sep_opt;
1820         char *p;
1821         char dgid[3];
1822         substring_t args[MAX_OPT_ARGS];
1823         int opt_mask = 0;
1824         int token;
1825         int ret = -EINVAL;
1826         int i;
1827
1828         options = kstrdup(buf, GFP_KERNEL);
1829         if (!options)
1830                 return -ENOMEM;
1831
1832         sep_opt = options;
1833         while ((p = strsep(&sep_opt, ",")) != NULL) {
1834                 if (!*p)
1835                         continue;
1836
1837                 token = match_token(p, srp_opt_tokens, args);
1838                 opt_mask |= token;
1839
1840                 switch (token) {
1841                 case SRP_OPT_ID_EXT:
1842                         p = match_strdup(args);
1843                         if (!p) {
1844                                 ret = -ENOMEM;
1845                                 goto out;
1846                         }
1847                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1848                         kfree(p);
1849                         break;
1850
1851                 case SRP_OPT_IOC_GUID:
1852                         p = match_strdup(args);
1853                         if (!p) {
1854                                 ret = -ENOMEM;
1855                                 goto out;
1856                         }
1857                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1858                         kfree(p);
1859                         break;
1860
1861                 case SRP_OPT_DGID:
1862                         p = match_strdup(args);
1863                         if (!p) {
1864                                 ret = -ENOMEM;
1865                                 goto out;
1866                         }
1867                         if (strlen(p) != 32) {
1868                                 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1869                                 kfree(p);
1870                                 goto out;
1871                         }
1872
1873                         for (i = 0; i < 16; ++i) {
1874                                 strlcpy(dgid, p + i * 2, 3);
1875                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1876                         }
1877                         kfree(p);
1878                         memcpy(target->orig_dgid, target->path.dgid.raw, 16);
1879                         break;
1880
1881                 case SRP_OPT_PKEY:
1882                         if (match_hex(args, &token)) {
1883                                 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1884                                 goto out;
1885                         }
1886                         target->path.pkey = cpu_to_be16(token);
1887                         break;
1888
1889                 case SRP_OPT_SERVICE_ID:
1890                         p = match_strdup(args);
1891                         if (!p) {
1892                                 ret = -ENOMEM;
1893                                 goto out;
1894                         }
1895                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1896                         target->path.service_id = target->service_id;
1897                         kfree(p);
1898                         break;
1899
1900                 case SRP_OPT_MAX_SECT:
1901                         if (match_int(args, &token)) {
1902                                 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1903                                 goto out;
1904                         }
1905                         target->scsi_host->max_sectors = token;
1906                         break;
1907
1908                 case SRP_OPT_MAX_CMD_PER_LUN:
1909                         if (match_int(args, &token)) {
1910                                 printk(KERN_WARNING PFX "bad max cmd_per_lun parameter '%s'\n", p);
1911                                 goto out;
1912                         }
1913                         target->scsi_host->cmd_per_lun = min(token, SRP_CMD_SQ_SIZE);
1914                         break;
1915
1916                 case SRP_OPT_IO_CLASS:
1917                         if (match_hex(args, &token)) {
1918                                 printk(KERN_WARNING PFX "bad  IO class parameter '%s' \n", p);
1919                                 goto out;
1920                         }
1921                         if (token != SRP_REV10_IB_IO_CLASS &&
1922                             token != SRP_REV16A_IB_IO_CLASS) {
1923                                 printk(KERN_WARNING PFX "unknown IO class parameter value"
1924                                        " %x specified (use %x or %x).\n",
1925                                        token, SRP_REV10_IB_IO_CLASS, SRP_REV16A_IB_IO_CLASS);
1926                                 goto out;
1927                         }
1928                         target->io_class = token;
1929                         break;
1930
1931                 case SRP_OPT_INITIATOR_EXT:
1932                         p = match_strdup(args);
1933                         if (!p) {
1934                                 ret = -ENOMEM;
1935                                 goto out;
1936                         }
1937                         target->initiator_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1938                         kfree(p);
1939                         break;
1940
1941                 default:
1942                         printk(KERN_WARNING PFX "unknown parameter or missing value "
1943                                "'%s' in target creation request\n", p);
1944                         goto out;
1945                 }
1946         }
1947
1948         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1949                 ret = 0;
1950         else
1951                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1952                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1953                             !(srp_opt_tokens[i].token & opt_mask))
1954                                 printk(KERN_WARNING PFX "target creation request is "
1955                                        "missing parameter '%s'\n",
1956                                        srp_opt_tokens[i].pattern);
1957
1958 out:
1959         kfree(options);
1960         return ret;
1961 }
1962
1963 static ssize_t srp_create_target(struct device *dev,
1964                                  struct device_attribute *attr,
1965                                  const char *buf, size_t count)
1966 {
1967         struct srp_host *host =
1968                 container_of(dev, struct srp_host, dev);
1969         struct Scsi_Host *target_host;
1970         struct srp_target_port *target;
1971         int ret;
1972         int i;
1973
1974         target_host = scsi_host_alloc(&srp_template,
1975                                       sizeof (struct srp_target_port));
1976         if (!target_host)
1977                 return -ENOMEM;
1978
1979         target_host->transportt = ib_srp_transport_template;
1980         target_host->max_lun     = SRP_MAX_LUN;
1981         target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
1982
1983         target = host_to_target(target_host);
1984
1985         target->io_class   = SRP_REV16A_IB_IO_CLASS;
1986         target->scsi_host  = target_host;
1987         target->srp_host   = host;
1988
1989         INIT_LIST_HEAD(&target->free_reqs);
1990         INIT_LIST_HEAD(&target->req_queue);
1991         for (i = 0; i < SRP_CMD_SQ_SIZE; ++i) {
1992                 target->req_ring[i].index = i;
1993                 list_add_tail(&target->req_ring[i].list, &target->free_reqs);
1994         }
1995
1996         ret = srp_parse_options(buf, target);
1997         if (ret)
1998                 goto err;
1999
2000         ib_query_gid(host->srp_dev->dev, host->port, 0, &target->path.sgid);
2001
2002         shost_printk(KERN_DEBUG, target->scsi_host, PFX
2003                      "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
2004                      "service_id %016llx dgid %pI6\n",
2005                (unsigned long long) be64_to_cpu(target->id_ext),
2006                (unsigned long long) be64_to_cpu(target->ioc_guid),
2007                be16_to_cpu(target->path.pkey),
2008                (unsigned long long) be64_to_cpu(target->service_id),
2009                target->path.dgid.raw);
2010
2011         ret = srp_create_target_ib(target);
2012         if (ret)
2013                 goto err;
2014
2015         ret = srp_new_cm_id(target);
2016         if (ret)
2017                 goto err_free;
2018
2019         target->qp_in_error = 0;
2020         ret = srp_connect_target(target);
2021         if (ret) {
2022                 shost_printk(KERN_ERR, target->scsi_host,
2023                              PFX "Connection failed\n");
2024                 goto err_cm_id;
2025         }
2026
2027         ret = srp_add_target(host, target);
2028         if (ret)
2029                 goto err_disconnect;
2030
2031         return count;
2032
2033 err_disconnect:
2034         srp_disconnect_target(target);
2035
2036 err_cm_id:
2037         ib_destroy_cm_id(target->cm_id);
2038
2039 err_free:
2040         srp_free_target_ib(target);
2041
2042 err:
2043         scsi_host_put(target_host);
2044
2045         return ret;
2046 }
2047
2048 static DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
2049
2050 static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
2051                           char *buf)
2052 {
2053         struct srp_host *host = container_of(dev, struct srp_host, dev);
2054
2055         return sprintf(buf, "%s\n", host->srp_dev->dev->name);
2056 }
2057
2058 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
2059
2060 static ssize_t show_port(struct device *dev, struct device_attribute *attr,
2061                          char *buf)
2062 {
2063         struct srp_host *host = container_of(dev, struct srp_host, dev);
2064
2065         return sprintf(buf, "%d\n", host->port);
2066 }
2067
2068 static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
2069
2070 static struct srp_host *srp_add_port(struct srp_device *device, u8 port)
2071 {
2072         struct srp_host *host;
2073
2074         host = kzalloc(sizeof *host, GFP_KERNEL);
2075         if (!host)
2076                 return NULL;
2077
2078         INIT_LIST_HEAD(&host->target_list);
2079         spin_lock_init(&host->target_lock);
2080         init_completion(&host->released);
2081         host->srp_dev = device;
2082         host->port = port;
2083
2084         host->dev.class = &srp_class;
2085         host->dev.parent = device->dev->dma_device;
2086         dev_set_name(&host->dev, "srp-%s-%d", device->dev->name, port);
2087
2088         if (device_register(&host->dev))
2089                 goto free_host;
2090         if (device_create_file(&host->dev, &dev_attr_add_target))
2091                 goto err_class;
2092         if (device_create_file(&host->dev, &dev_attr_ibdev))
2093                 goto err_class;
2094         if (device_create_file(&host->dev, &dev_attr_port))
2095                 goto err_class;
2096
2097         return host;
2098
2099 err_class:
2100         device_unregister(&host->dev);
2101
2102 free_host:
2103         kfree(host);
2104
2105         return NULL;
2106 }
2107
2108 static void srp_add_one(struct ib_device *device)
2109 {
2110         struct srp_device *srp_dev;
2111         struct ib_device_attr *dev_attr;
2112         struct ib_fmr_pool_param fmr_param;
2113         struct srp_host *host;
2114         int s, e, p;
2115
2116         dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
2117         if (!dev_attr)
2118                 return;
2119
2120         if (ib_query_device(device, dev_attr)) {
2121                 printk(KERN_WARNING PFX "Query device failed for %s\n",
2122                        device->name);
2123                 goto free_attr;
2124         }
2125
2126         srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
2127         if (!srp_dev)
2128                 goto free_attr;
2129
2130         /*
2131          * Use the smallest page size supported by the HCA, down to a
2132          * minimum of 512 bytes (which is the smallest sector that a
2133          * SCSI command will ever carry).
2134          */
2135         srp_dev->fmr_page_shift = max(9, ffs(dev_attr->page_size_cap) - 1);
2136         srp_dev->fmr_page_size  = 1 << srp_dev->fmr_page_shift;
2137         srp_dev->fmr_page_mask  = ~((u64) srp_dev->fmr_page_size - 1);
2138
2139         INIT_LIST_HEAD(&srp_dev->dev_list);
2140
2141         srp_dev->dev = device;
2142         srp_dev->pd  = ib_alloc_pd(device);
2143         if (IS_ERR(srp_dev->pd))
2144                 goto free_dev;
2145
2146         srp_dev->mr = ib_get_dma_mr(srp_dev->pd,
2147                                     IB_ACCESS_LOCAL_WRITE |
2148                                     IB_ACCESS_REMOTE_READ |
2149                                     IB_ACCESS_REMOTE_WRITE);
2150         if (IS_ERR(srp_dev->mr))
2151                 goto err_pd;
2152
2153         memset(&fmr_param, 0, sizeof fmr_param);
2154         fmr_param.pool_size         = SRP_FMR_POOL_SIZE;
2155         fmr_param.dirty_watermark   = SRP_FMR_DIRTY_SIZE;
2156         fmr_param.cache             = 1;
2157         fmr_param.max_pages_per_fmr = SRP_FMR_SIZE;
2158         fmr_param.page_shift        = srp_dev->fmr_page_shift;
2159         fmr_param.access            = (IB_ACCESS_LOCAL_WRITE |
2160                                        IB_ACCESS_REMOTE_WRITE |
2161                                        IB_ACCESS_REMOTE_READ);
2162
2163         srp_dev->fmr_pool = ib_create_fmr_pool(srp_dev->pd, &fmr_param);
2164         if (IS_ERR(srp_dev->fmr_pool))
2165                 srp_dev->fmr_pool = NULL;
2166
2167         if (device->node_type == RDMA_NODE_IB_SWITCH) {
2168                 s = 0;
2169                 e = 0;
2170         } else {
2171                 s = 1;
2172                 e = device->phys_port_cnt;
2173         }
2174
2175         for (p = s; p <= e; ++p) {
2176                 host = srp_add_port(srp_dev, p);
2177                 if (host)
2178                         list_add_tail(&host->list, &srp_dev->dev_list);
2179         }
2180
2181         ib_set_client_data(device, &srp_client, srp_dev);
2182
2183         goto free_attr;
2184
2185 err_pd:
2186         ib_dealloc_pd(srp_dev->pd);
2187
2188 free_dev:
2189         kfree(srp_dev);
2190
2191 free_attr:
2192         kfree(dev_attr);
2193 }
2194
2195 static void srp_remove_one(struct ib_device *device)
2196 {
2197         struct srp_device *srp_dev;
2198         struct srp_host *host, *tmp_host;
2199         LIST_HEAD(target_list);
2200         struct srp_target_port *target, *tmp_target;
2201
2202         srp_dev = ib_get_client_data(device, &srp_client);
2203
2204         list_for_each_entry_safe(host, tmp_host, &srp_dev->dev_list, list) {
2205                 device_unregister(&host->dev);
2206                 /*
2207                  * Wait for the sysfs entry to go away, so that no new
2208                  * target ports can be created.
2209                  */
2210                 wait_for_completion(&host->released);
2211
2212                 /*
2213                  * Mark all target ports as removed, so we stop queueing
2214                  * commands and don't try to reconnect.
2215                  */
2216                 spin_lock(&host->target_lock);
2217                 list_for_each_entry(target, &host->target_list, list) {
2218                         spin_lock_irq(target->scsi_host->host_lock);
2219                         target->state = SRP_TARGET_REMOVED;
2220                         spin_unlock_irq(target->scsi_host->host_lock);
2221                 }
2222                 spin_unlock(&host->target_lock);
2223
2224                 /*
2225                  * Wait for any reconnection tasks that may have
2226                  * started before we marked our target ports as
2227                  * removed, and any target port removal tasks.
2228                  */
2229                 flush_scheduled_work();
2230
2231                 list_for_each_entry_safe(target, tmp_target,
2232                                          &host->target_list, list) {
2233                         srp_remove_host(target->scsi_host);
2234                         scsi_remove_host(target->scsi_host);
2235                         srp_disconnect_target(target);
2236                         ib_destroy_cm_id(target->cm_id);
2237                         srp_free_target_ib(target);
2238                         scsi_host_put(target->scsi_host);
2239                 }
2240
2241                 kfree(host);
2242         }
2243
2244         if (srp_dev->fmr_pool)
2245                 ib_destroy_fmr_pool(srp_dev->fmr_pool);
2246         ib_dereg_mr(srp_dev->mr);
2247         ib_dealloc_pd(srp_dev->pd);
2248
2249         kfree(srp_dev);
2250 }
2251
2252 static struct srp_function_template ib_srp_transport_functions = {
2253 };
2254
2255 static int __init srp_init_module(void)
2256 {
2257         int ret;
2258
2259         BUILD_BUG_ON_NOT_POWER_OF_2(SRP_SQ_SIZE);
2260         BUILD_BUG_ON_NOT_POWER_OF_2(SRP_RQ_SIZE);
2261
2262         if (srp_sg_tablesize > 255) {
2263                 printk(KERN_WARNING PFX "Clamping srp_sg_tablesize to 255\n");
2264                 srp_sg_tablesize = 255;
2265         }
2266
2267         ib_srp_transport_template =
2268                 srp_attach_transport(&ib_srp_transport_functions);
2269         if (!ib_srp_transport_template)
2270                 return -ENOMEM;
2271
2272         srp_template.sg_tablesize = srp_sg_tablesize;
2273         srp_max_iu_len = (sizeof (struct srp_cmd) +
2274                           sizeof (struct srp_indirect_buf) +
2275                           srp_sg_tablesize * 16);
2276
2277         ret = class_register(&srp_class);
2278         if (ret) {
2279                 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
2280                 srp_release_transport(ib_srp_transport_template);
2281                 return ret;
2282         }
2283
2284         ib_sa_register_client(&srp_sa_client);
2285
2286         ret = ib_register_client(&srp_client);
2287         if (ret) {
2288                 printk(KERN_ERR PFX "couldn't register IB client\n");
2289                 srp_release_transport(ib_srp_transport_template);
2290                 ib_sa_unregister_client(&srp_sa_client);
2291                 class_unregister(&srp_class);
2292                 return ret;
2293         }
2294
2295         return 0;
2296 }
2297
2298 static void __exit srp_cleanup_module(void)
2299 {
2300         ib_unregister_client(&srp_client);
2301         ib_sa_unregister_client(&srp_sa_client);
2302         class_unregister(&srp_class);
2303         srp_release_transport(ib_srp_transport_template);
2304 }
2305
2306 module_init(srp_init_module);
2307 module_exit(srp_cleanup_module);