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  * $Id: ib_srp.c 3932 2005-11-01 17:19:29Z roland $
  33  */
  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 <asm/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
  51 #include <rdma/ib_cache.h>
  52
  53 #include "ib_srp.h"
  54
  55 #define DRV_NAME        "ib_srp"
  56 #define PFX             DRV_NAME ": "
  57 #define DRV_VERSION     "0.2"
  58 #define DRV_RELDATE     "November 1, 2005"
  59
  60 MODULE_AUTHOR("Roland Dreier");
  61 MODULE_DESCRIPTION("InfiniBand SCSI RDMA Protocol initiator "
  62                    "v" DRV_VERSION " (" DRV_RELDATE ")");
  63 MODULE_LICENSE("Dual BSD/GPL");
  64
  65 static int topspin_workarounds = 1;
  66
  67 module_param(topspin_workarounds, int, 0444);
  68 MODULE_PARM_DESC(topspin_workarounds,
  69                  "Enable workarounds for Topspin/Cisco SRP target bugs if != 0");
  70
  71 static const u8 topspin_oui[3] = { 0x00, 0x05, 0xad };
  72
  73 static void srp_add_one(struct ib_device *device);
  74 static void srp_remove_one(struct ib_device *device);
  75 static void srp_completion(struct ib_cq *cq, void *target_ptr);
  76 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
  77
  78 static struct ib_client srp_client = {
  79         .name   = "srp",
  80         .add    = srp_add_one,
  81         .remove = srp_remove_one
  82 };
  83
  84 static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
  85 {
  86         return (struct srp_target_port *) host->hostdata;
  87 }
  88
  89 static const char *srp_target_info(struct Scsi_Host *host)
  90 {
  91         return host_to_target(host)->target_name;
  92 }
  93
  94 static struct srp_iu *srp_alloc_iu(struct srp_host *host, size_t size,
  95                                    gfp_t gfp_mask,
  96                                    enum dma_data_direction direction)
  97 {
  98         struct srp_iu *iu;
  99
 100         iu = kmalloc(sizeof *iu, gfp_mask);
 101         if (!iu)
 102                 goto out;
 103
 104         iu->buf = kzalloc(size, gfp_mask);
 105         if (!iu->buf)
 106                 goto out_free_iu;
 107
 108         iu->dma = dma_map_single(host->dev->dma_device, iu->buf, size, direction);
 109         if (dma_mapping_error(iu->dma))
 110                 goto out_free_buf;
 111
 112         iu->size      = size;
 113         iu->direction = direction;
 114
 115         return iu;
 116
 117 out_free_buf:
 118         kfree(iu->buf);
 119 out_free_iu:
 120         kfree(iu);
 121 out:
 122         return NULL;
 123 }
 124
 125 static void srp_free_iu(struct srp_host *host, struct srp_iu *iu)
 126 {
 127         if (!iu)
 128                 return;
 129
 130         dma_unmap_single(host->dev->dma_device, iu->dma, iu->size, iu->direction);
 131         kfree(iu->buf);
 132         kfree(iu);
 133 }
 134
 135 static void srp_qp_event(struct ib_event *event, void *context)
 136 {
 137         printk(KERN_ERR PFX "QP event %d\n", event->event);
 138 }
 139
 140 static int srp_init_qp(struct srp_target_port *target,
 141                        struct ib_qp *qp)
 142 {
 143         struct ib_qp_attr *attr;
 144         int ret;
 145
 146         attr = kmalloc(sizeof *attr, GFP_KERNEL);
 147         if (!attr)
 148                 return -ENOMEM;
 149
 150         ret = ib_find_cached_pkey(target->srp_host->dev,
 151                                   target->srp_host->port,
 152                                   be16_to_cpu(target->path.pkey),
 153                                   &attr->pkey_index);
 154         if (ret)
 155                 goto out;
 156
 157         attr->qp_state        = IB_QPS_INIT;
 158         attr->qp_access_flags = (IB_ACCESS_REMOTE_READ |
 159                                     IB_ACCESS_REMOTE_WRITE);
 160         attr->port_num        = target->srp_host->port;
 161
 162         ret = ib_modify_qp(qp, attr,
 163                            IB_QP_STATE          |
 164                            IB_QP_PKEY_INDEX     |
 165                            IB_QP_ACCESS_FLAGS   |
 166                            IB_QP_PORT);
 167
 168 out:
 169         kfree(attr);
 170         return ret;
 171 }
 172
 173 static int srp_create_target_ib(struct srp_target_port *target)
 174 {
 175         struct ib_qp_init_attr *init_attr;
 176         int ret;
 177
 178         init_attr = kzalloc(sizeof *init_attr, GFP_KERNEL);
 179         if (!init_attr)
 180                 return -ENOMEM;
 181
 182         target->cq = ib_create_cq(target->srp_host->dev, srp_completion,
 183                                   NULL, target, SRP_CQ_SIZE);
 184         if (IS_ERR(target->cq)) {
 185                 ret = PTR_ERR(target->cq);
 186                 goto out;
 187         }
 188
 189         ib_req_notify_cq(target->cq, IB_CQ_NEXT_COMP);
 190
 191         init_attr->event_handler       = srp_qp_event;
 192         init_attr->cap.max_send_wr     = SRP_SQ_SIZE;
 193         init_attr->cap.max_recv_wr     = SRP_RQ_SIZE;
 194         init_attr->cap.max_recv_sge    = 1;
 195         init_attr->cap.max_send_sge    = 1;
 196         init_attr->sq_sig_type         = IB_SIGNAL_ALL_WR;
 197         init_attr->qp_type             = IB_QPT_RC;
 198         init_attr->send_cq             = target->cq;
 199         init_attr->recv_cq             = target->cq;
 200
 201         target->qp = ib_create_qp(target->srp_host->pd, init_attr);
 202         if (IS_ERR(target->qp)) {
 203                 ret = PTR_ERR(target->qp);
 204                 ib_destroy_cq(target->cq);
 205                 goto out;
 206         }
 207
 208         ret = srp_init_qp(target, target->qp);
 209         if (ret) {
 210                 ib_destroy_qp(target->qp);
 211                 ib_destroy_cq(target->cq);
 212                 goto out;
 213         }
 214
 215 out:
 216         kfree(init_attr);
 217         return ret;
 218 }
 219
 220 static void srp_free_target_ib(struct srp_target_port *target)
 221 {
 222         int i;
 223
 224         ib_destroy_qp(target->qp);
 225         ib_destroy_cq(target->cq);
 226
 227         for (i = 0; i < SRP_RQ_SIZE; ++i)
 228                 srp_free_iu(target->srp_host, target->rx_ring[i]);
 229         for (i = 0; i < SRP_SQ_SIZE + 1; ++i)
 230                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 231 }
 232
 233 static void srp_path_rec_completion(int status,
 234                                     struct ib_sa_path_rec *pathrec,
 235                                     void *target_ptr)
 236 {
 237         struct srp_target_port *target = target_ptr;
 238
 239         target->status = status;
 240         if (status)
 241                 printk(KERN_ERR PFX "Got failed path rec status %d\n", status);
 242         else
 243                 target->path = *pathrec;
 244         complete(&target->done);
 245 }
 246
 247 static int srp_lookup_path(struct srp_target_port *target)
 248 {
 249         target->path.numb_path = 1;
 250
 251         init_completion(&target->done);
 252
 253         target->path_query_id = ib_sa_path_rec_get(target->srp_host->dev,
 254                                                    target->srp_host->port,
 255                                                    &target->path,
 256                                                    IB_SA_PATH_REC_DGID          |
 257                                                    IB_SA_PATH_REC_SGID          |
 258                                                    IB_SA_PATH_REC_NUMB_PATH     |
 259                                                    IB_SA_PATH_REC_PKEY,
 260                                                    SRP_PATH_REC_TIMEOUT_MS,
 261                                                    GFP_KERNEL,
 262                                                    srp_path_rec_completion,
 263                                                    target, &target->path_query);
 264         if (target->path_query_id < 0)
 265                 return target->path_query_id;
 266
 267         wait_for_completion(&target->done);
 268
 269         if (target->status < 0)
 270                 printk(KERN_WARNING PFX "Path record query failed\n");
 271
 272         return target->status;
 273 }
 274
 275 static int srp_send_req(struct srp_target_port *target)
 276 {
 277         struct {
 278                 struct ib_cm_req_param param;
 279                 struct srp_login_req   priv;
 280         } *req = NULL;
 281         int status;
 282
 283         req = kzalloc(sizeof *req, GFP_KERNEL);
 284         if (!req)
 285                 return -ENOMEM;
 286
 287         req->param.primary_path               = &target->path;
 288         req->param.alternate_path             = NULL;
 289         req->param.service_id                 = target->service_id;
 290         req->param.qp_num                     = target->qp->qp_num;
 291         req->param.qp_type                    = target->qp->qp_type;
 292         req->param.private_data               = &req->priv;
 293         req->param.private_data_len           = sizeof req->priv;
 294         req->param.flow_control               = 1;
 295
 296         get_random_bytes(&req->param.starting_psn, 4);
 297         req->param.starting_psn              &= 0xffffff;
 298
 299         /*
 300          * Pick some arbitrary defaults here; we could make these
 301          * module parameters if anyone cared about setting them.
 302          */
 303         req->param.responder_resources        = 4;
 304         req->param.remote_cm_response_timeout = 20;
 305         req->param.local_cm_response_timeout  = 20;
 306         req->param.retry_count                = 7;
 307         req->param.rnr_retry_count            = 7;
 308         req->param.max_cm_retries             = 15;
 309
 310         req->priv.opcode        = SRP_LOGIN_REQ;
 311         req->priv.tag           = 0;
 312         req->priv.req_it_iu_len = cpu_to_be32(SRP_MAX_IU_LEN);
 313         req->priv.req_buf_fmt   = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
 314                                               SRP_BUF_FORMAT_INDIRECT);
 315         memcpy(req->priv.initiator_port_id, target->srp_host->initiator_port_id, 16);
 316         /*
 317          * Topspin/Cisco SRP targets will reject our login unless we
 318          * zero out the first 8 bytes of our initiator port ID.  The
 319          * second 8 bytes must be our local node GUID, but we always
 320          * use that anyway.
 321          */
 322         if (topspin_workarounds && !memcmp(&target->ioc_guid, topspin_oui, 3)) {
 323                 printk(KERN_DEBUG PFX "Topspin/Cisco initiator port ID workaround "
 324                        "activated for target GUID %016llx\n",
 325                        (unsigned long long) be64_to_cpu(target->ioc_guid));
 326                 memset(req->priv.initiator_port_id, 0, 8);
 327         }
 328         memcpy(req->priv.target_port_id,     &target->id_ext, 8);
 329         memcpy(req->priv.target_port_id + 8, &target->ioc_guid, 8);
 330
 331         status = ib_send_cm_req(target->cm_id, &req->param);
 332
 333         kfree(req);
 334
 335         return status;
 336 }
 337
 338 static void srp_disconnect_target(struct srp_target_port *target)
 339 {
 340         /* XXX should send SRP_I_LOGOUT request */
 341
 342         init_completion(&target->done);
 343         ib_send_cm_dreq(target->cm_id, NULL, 0);
 344         wait_for_completion(&target->done);
 345 }
 346
 347 static void srp_remove_work(void *target_ptr)
 348 {
 349         struct srp_target_port *target = target_ptr;
 350
 351         spin_lock_irq(target->scsi_host->host_lock);
 352         if (target->state != SRP_TARGET_DEAD) {
 353                 spin_unlock_irq(target->scsi_host->host_lock);
 354                 scsi_host_put(target->scsi_host);
 355                 return;
 356         }
 357         target->state = SRP_TARGET_REMOVED;
 358         spin_unlock_irq(target->scsi_host->host_lock);
 359
 360         mutex_lock(&target->srp_host->target_mutex);
 361         list_del(&target->list);
 362         mutex_unlock(&target->srp_host->target_mutex);
 363
 364         scsi_remove_host(target->scsi_host);
 365         ib_destroy_cm_id(target->cm_id);
 366         srp_free_target_ib(target);
 367         scsi_host_put(target->scsi_host);
 368         /* And another put to really free the target port... */
 369         scsi_host_put(target->scsi_host);
 370 }
 371
 372 static int srp_connect_target(struct srp_target_port *target)
 373 {
 374         int ret;
 375
 376         ret = srp_lookup_path(target);
 377         if (ret)
 378                 return ret;
 379
 380         while (1) {
 381                 init_completion(&target->done);
 382                 ret = srp_send_req(target);
 383                 if (ret)
 384                         return ret;
 385                 wait_for_completion(&target->done);
 386
 387                 /*
 388                  * The CM event handling code will set status to
 389                  * SRP_PORT_REDIRECT if we get a port redirect REJ
 390                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
 391                  * redirect REJ back.
 392                  */
 393                 switch (target->status) {
 394                 case 0:
 395                         return 0;
 396
 397                 case SRP_PORT_REDIRECT:
 398                         ret = srp_lookup_path(target);
 399                         if (ret)
 400                                 return ret;
 401                         break;
 402
 403                 case SRP_DLID_REDIRECT:
 404                         break;
 405
 406                 default:
 407                         return target->status;
 408                 }
 409         }
 410 }
 411
 412 static int srp_reconnect_target(struct srp_target_port *target)
 413 {
 414         struct ib_cm_id *new_cm_id;
 415         struct ib_qp_attr qp_attr;
 416         struct srp_request *req;
 417         struct ib_wc wc;
 418         int ret;
 419         int i;
 420
 421         spin_lock_irq(target->scsi_host->host_lock);
 422         if (target->state != SRP_TARGET_LIVE) {
 423                 spin_unlock_irq(target->scsi_host->host_lock);
 424                 return -EAGAIN;
 425         }
 426         target->state = SRP_TARGET_CONNECTING;
 427         spin_unlock_irq(target->scsi_host->host_lock);
 428
 429         srp_disconnect_target(target);
 430         /*
 431          * Now get a new local CM ID so that we avoid confusing the
 432          * target in case things are really fouled up.
 433          */
 434         new_cm_id = ib_create_cm_id(target->srp_host->dev,
 435                                     srp_cm_handler, target);
 436         if (IS_ERR(new_cm_id)) {
 437                 ret = PTR_ERR(new_cm_id);
 438                 goto err;
 439         }
 440         ib_destroy_cm_id(target->cm_id);
 441         target->cm_id = new_cm_id;
 442
 443         qp_attr.qp_state = IB_QPS_RESET;
 444         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
 445         if (ret)
 446                 goto err;
 447
 448         ret = srp_init_qp(target, target->qp);
 449         if (ret)
 450                 goto err;
 451
 452         while (ib_poll_cq(target->cq, 1, &wc) > 0)
 453                 ; /* nothing */
 454
 455         list_for_each_entry(req, &target->req_queue, list) {
 456                 req->scmnd->result = DID_RESET << 16;
 457                 req->scmnd->scsi_done(req->scmnd);
 458         }
 459
 460         target->rx_head  = 0;
 461         target->tx_head  = 0;
 462         target->tx_tail  = 0;
 463         target->req_head = 0;
 464         for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
 465                 target->req_ring[i].next = i + 1;
 466         target->req_ring[SRP_SQ_SIZE - 1].next = -1;
 467         INIT_LIST_HEAD(&target->req_queue);
 468
 469         ret = srp_connect_target(target);
 470         if (ret)
 471                 goto err;
 472
 473         spin_lock_irq(target->scsi_host->host_lock);
 474         if (target->state == SRP_TARGET_CONNECTING) {
 475                 ret = 0;
 476                 target->state = SRP_TARGET_LIVE;
 477         } else
 478                 ret = -EAGAIN;
 479         spin_unlock_irq(target->scsi_host->host_lock);
 480
 481         return ret;
 482
 483 err:
 484         printk(KERN_ERR PFX "reconnect failed (%d), removing target port.\n", ret);
 485
 486         /*
 487          * We couldn't reconnect, so kill our target port off.
 488          * However, we have to defer the real removal because we might
 489          * be in the context of the SCSI error handler now, which
 490          * would deadlock if we call scsi_remove_host().
 491          */
 492         spin_lock_irq(target->scsi_host->host_lock);
 493         if (target->state == SRP_TARGET_CONNECTING) {
 494                 target->state = SRP_TARGET_DEAD;
 495                 INIT_WORK(&target->work, srp_remove_work, target);
 496                 schedule_work(&target->work);
 497         }
 498         spin_unlock_irq(target->scsi_host->host_lock);
 499
 500         return ret;
 501 }
 502
 503 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
 504                         struct srp_request *req)
 505 {
 506         struct scatterlist *scat;
 507         struct srp_cmd *cmd = req->cmd->buf;
 508         int len, nents, count;
 509         int i;
 510         u8 fmt;
 511
 512         if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
 513                 return sizeof (struct srp_cmd);
 514
 515         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
 516             scmnd->sc_data_direction != DMA_TO_DEVICE) {
 517                 printk(KERN_WARNING PFX "Unhandled data direction %d\n",
 518                        scmnd->sc_data_direction);
 519                 return -EINVAL;
 520         }
 521
 522         /*
 523          * This handling of non-SG commands can be killed when the
 524          * SCSI midlayer no longer generates non-SG commands.
 525          */
 526         if (likely(scmnd->use_sg)) {
 527                 nents = scmnd->use_sg;
 528                 scat  = scmnd->request_buffer;
 529         } else {
 530                 nents = 1;
 531                 scat  = &req->fake_sg;
 532                 sg_init_one(scat, scmnd->request_buffer, scmnd->request_bufflen);
 533         }
 534
 535         count = dma_map_sg(target->srp_host->dev->dma_device, scat, nents,
 536                            scmnd->sc_data_direction);
 537
 538         if (count == 1) {
 539                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 540
 541                 fmt = SRP_DATA_DESC_DIRECT;
 542
 543                 buf->va  = cpu_to_be64(sg_dma_address(scat));
 544                 buf->key = cpu_to_be32(target->srp_host->mr->rkey);
 545                 buf->len = cpu_to_be32(sg_dma_len(scat));
 546
 547                 len = sizeof (struct srp_cmd) +
 548                         sizeof (struct srp_direct_buf);
 549         } else {
 550                 struct srp_indirect_buf *buf = (void *) cmd->add_data;
 551                 u32 datalen = 0;
 552
 553                 fmt = SRP_DATA_DESC_INDIRECT;
 554
 555                 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 556                         cmd->data_out_desc_cnt = count;
 557                 else
 558                         cmd->data_in_desc_cnt = count;
 559
 560                 buf->table_desc.va  = cpu_to_be64(req->cmd->dma +
 561                                                   sizeof *cmd +
 562                                                   sizeof *buf);
 563                 buf->table_desc.key =
 564                         cpu_to_be32(target->srp_host->mr->rkey);
 565                 buf->table_desc.len =
 566                         cpu_to_be32(count * sizeof (struct srp_direct_buf));
 567
 568                 for (i = 0; i < count; ++i) {
 569                         buf->desc_list[i].va  = cpu_to_be64(sg_dma_address(&scat[i]));
 570                         buf->desc_list[i].key =
 571                                 cpu_to_be32(target->srp_host->mr->rkey);
 572                         buf->desc_list[i].len = cpu_to_be32(sg_dma_len(&scat[i]));
 573
 574                         datalen += sg_dma_len(&scat[i]);
 575                 }
 576
 577                 buf->len = cpu_to_be32(datalen);
 578
 579                 len = sizeof (struct srp_cmd) +
 580                         sizeof (struct srp_indirect_buf) +
 581                         count * sizeof (struct srp_direct_buf);
 582         }
 583
 584         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 585                 cmd->buf_fmt = fmt << 4;
 586         else
 587                 cmd->buf_fmt = fmt;
 588
 589         return len;
 590 }
 591
 592 static void srp_unmap_data(struct scsi_cmnd *scmnd,
 593                            struct srp_target_port *target,
 594                            struct srp_request *req)
 595 {
 596         struct scatterlist *scat;
 597         int nents;
 598
 599         if (!scmnd->request_buffer ||
 600             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
 601              scmnd->sc_data_direction != DMA_FROM_DEVICE))
 602                 return;
 603
 604         /*
 605          * This handling of non-SG commands can be killed when the
 606          * SCSI midlayer no longer generates non-SG commands.
 607          */
 608         if (likely(scmnd->use_sg)) {
 609                 nents = scmnd->use_sg;
 610                 scat  = scmnd->request_buffer;
 611         } else {
 612                 nents = 1;
 613                 scat  = &req->fake_sg;
 614         }
 615
 616         dma_unmap_sg(target->srp_host->dev->dma_device, scat, nents,
 617                      scmnd->sc_data_direction);
 618 }
 619
 620 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req,
 621                            int index)
 622 {
 623         list_del(&req->list);
 624         req->next = target->req_head;
 625         target->req_head = index;
 626 }
 627
 628 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
 629 {
 630         struct srp_request *req;
 631         struct scsi_cmnd *scmnd;
 632         unsigned long flags;
 633         s32 delta;
 634
 635         delta = (s32) be32_to_cpu(rsp->req_lim_delta);
 636
 637         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 638
 639         target->req_lim += delta;
 640
 641         req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
 642
 643         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
 644                 if (be32_to_cpu(rsp->resp_data_len) < 4)
 645                         req->tsk_status = -1;
 646                 else
 647                         req->tsk_status = rsp->data[3];
 648                 complete(&req->done);
 649         } else {
 650                 scmnd         = req->scmnd;
 651                 if (!scmnd)
 652                         printk(KERN_ERR "Null scmnd for RSP w/tag %016llx\n",
 653                                (unsigned long long) rsp->tag);
 654                 scmnd->result = rsp->status;
 655
 656                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
 657                         memcpy(scmnd->sense_buffer, rsp->data +
 658                                be32_to_cpu(rsp->resp_data_len),
 659                                min_t(int, be32_to_cpu(rsp->sense_data_len),
 660                                      SCSI_SENSE_BUFFERSIZE));
 661                 }
 662
 663                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
 664                         scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
 665                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
 666                         scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
 667
 668                 srp_unmap_data(scmnd, target, req);
 669
 670                 if (!req->tsk_mgmt) {
 671                         req->scmnd = NULL;
 672                         scmnd->host_scribble = (void *) -1L;
 673                         scmnd->scsi_done(scmnd);
 674
 675                         srp_remove_req(target, req, rsp->tag & ~SRP_TAG_TSK_MGMT);
 676                 } else
 677                         req->cmd_done = 1;
 678         }
 679
 680         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 681 }
 682
 683 static void srp_reconnect_work(void *target_ptr)
 684 {
 685         struct srp_target_port *target = target_ptr;
 686
 687         srp_reconnect_target(target);
 688 }
 689
 690 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 691 {
 692         struct srp_iu *iu;
 693         u8 opcode;
 694
 695         iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
 696
 697         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 698                                 target->max_ti_iu_len, DMA_FROM_DEVICE);
 699
 700         opcode = *(u8 *) iu->buf;
 701
 702         if (0) {
 703                 int i;
 704
 705                 printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
 706
 707                 for (i = 0; i < wc->byte_len; ++i) {
 708                         if (i % 8 == 0)
 709                                 printk(KERN_ERR "  [%02x] ", i);
 710                         printk(" %02x", ((u8 *) iu->buf)[i]);
 711                         if ((i + 1) % 8 == 0)
 712                                 printk("\n");
 713                 }
 714
 715                 if (wc->byte_len % 8)
 716                         printk("\n");
 717         }
 718
 719         switch (opcode) {
 720         case SRP_RSP:
 721                 srp_process_rsp(target, iu->buf);
 722                 break;
 723
 724         case SRP_T_LOGOUT:
 725                 /* XXX Handle target logout */
 726                 printk(KERN_WARNING PFX "Got target logout request\n");
 727                 break;
 728
 729         default:
 730                 printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
 731                 break;
 732         }
 733
 734         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 735                                    target->max_ti_iu_len, DMA_FROM_DEVICE);
 736 }
 737
 738 static void srp_completion(struct ib_cq *cq, void *target_ptr)
 739 {
 740         struct srp_target_port *target = target_ptr;
 741         struct ib_wc wc;
 742         unsigned long flags;
 743
 744         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
 745         while (ib_poll_cq(cq, 1, &wc) > 0) {
 746                 if (wc.status) {
 747                         printk(KERN_ERR PFX "failed %s status %d\n",
 748                                wc.wr_id & SRP_OP_RECV ? "receive" : "send",
 749                                wc.status);
 750                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 751                         if (target->state == SRP_TARGET_LIVE)
 752                                 schedule_work(&target->work);
 753                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 754                         break;
 755                 }
 756
 757                 if (wc.wr_id & SRP_OP_RECV)
 758                         srp_handle_recv(target, &wc);
 759                 else
 760                         ++target->tx_tail;
 761         }
 762 }
 763
 764 static int __srp_post_recv(struct srp_target_port *target)
 765 {
 766         struct srp_iu *iu;
 767         struct ib_sge list;
 768         struct ib_recv_wr wr, *bad_wr;
 769         unsigned int next;
 770         int ret;
 771
 772         next     = target->rx_head & (SRP_RQ_SIZE - 1);
 773         wr.wr_id = next | SRP_OP_RECV;
 774         iu       = target->rx_ring[next];
 775
 776         list.addr   = iu->dma;
 777         list.length = iu->size;
 778         list.lkey   = target->srp_host->mr->lkey;
 779
 780         wr.next     = NULL;
 781         wr.sg_list  = &list;
 782         wr.num_sge  = 1;
 783
 784         ret = ib_post_recv(target->qp, &wr, &bad_wr);
 785         if (!ret)
 786                 ++target->rx_head;
 787
 788         return ret;
 789 }
 790
 791 static int srp_post_recv(struct srp_target_port *target)
 792 {
 793         unsigned long flags;
 794         int ret;
 795
 796         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 797         ret = __srp_post_recv(target);
 798         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 799
 800         return ret;
 801 }
 802
 803 /*
 804  * Must be called with target->scsi_host->host_lock held to protect
 805  * req_lim and tx_head.  Lock cannot be dropped between call here and
 806  * call to __srp_post_send().
 807  */
 808 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
 809 {
 810         if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
 811                 return NULL;
 812
 813         if (unlikely(target->req_lim < 1)) {
 814                 if (printk_ratelimit())
 815                         printk(KERN_DEBUG PFX "Target has req_lim %d\n",
 816                                target->req_lim);
 817                 return NULL;
 818         }
 819
 820         return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
 821 }
 822
 823 /*
 824  * Must be called with target->scsi_host->host_lock held to protect
 825  * req_lim and tx_head.
 826  */
 827 static int __srp_post_send(struct srp_target_port *target,
 828                            struct srp_iu *iu, int len)
 829 {
 830         struct ib_sge list;
 831         struct ib_send_wr wr, *bad_wr;
 832         int ret = 0;
 833
 834         list.addr   = iu->dma;
 835         list.length = len;
 836         list.lkey   = target->srp_host->mr->lkey;
 837
 838         wr.next       = NULL;
 839         wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
 840         wr.sg_list    = &list;
 841         wr.num_sge    = 1;
 842         wr.opcode     = IB_WR_SEND;
 843         wr.send_flags = IB_SEND_SIGNALED;
 844
 845         ret = ib_post_send(target->qp, &wr, &bad_wr);
 846
 847         if (!ret) {
 848                 ++target->tx_head;
 849                 --target->req_lim;
 850         }
 851
 852         return ret;
 853 }
 854
 855 static int srp_queuecommand(struct scsi_cmnd *scmnd,
 856                             void (*done)(struct scsi_cmnd *))
 857 {
 858         struct srp_target_port *target = host_to_target(scmnd->device->host);
 859         struct srp_request *req;
 860         struct srp_iu *iu;
 861         struct srp_cmd *cmd;
 862         long req_index;
 863         int len;
 864
 865         if (target->state == SRP_TARGET_CONNECTING)
 866                 goto err;
 867
 868         if (target->state == SRP_TARGET_DEAD ||
 869             target->state == SRP_TARGET_REMOVED) {
 870                 scmnd->result = DID_BAD_TARGET << 16;
 871                 done(scmnd);
 872                 return 0;
 873         }
 874
 875         iu = __srp_get_tx_iu(target);
 876         if (!iu)
 877                 goto err;
 878
 879         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 880                                 SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 881
 882         req_index = target->req_head;
 883
 884         scmnd->scsi_done     = done;
 885         scmnd->result        = 0;
 886         scmnd->host_scribble = (void *) req_index;
 887
 888         cmd = iu->buf;
 889         memset(cmd, 0, sizeof *cmd);
 890
 891         cmd->opcode = SRP_CMD;
 892         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
 893         cmd->tag    = req_index;
 894         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
 895
 896         req = &target->req_ring[req_index];
 897
 898         req->scmnd    = scmnd;
 899         req->cmd      = iu;
 900         req->cmd_done = 0;
 901         req->tsk_mgmt = NULL;
 902
 903         len = srp_map_data(scmnd, target, req);
 904         if (len < 0) {
 905                 printk(KERN_ERR PFX "Failed to map data\n");
 906                 goto err;
 907         }
 908
 909         if (__srp_post_recv(target)) {
 910                 printk(KERN_ERR PFX "Recv failed\n");
 911                 goto err_unmap;
 912         }
 913
 914         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 915                                    SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 916
 917         if (__srp_post_send(target, iu, len)) {
 918                 printk(KERN_ERR PFX "Send failed\n");
 919                 goto err_unmap;
 920         }
 921
 922         target->req_head = req->next;
 923         list_add_tail(&req->list, &target->req_queue);
 924
 925         return 0;
 926
 927 err_unmap:
 928         srp_unmap_data(scmnd, target, req);
 929
 930 err:
 931         return SCSI_MLQUEUE_HOST_BUSY;
 932 }
 933
 934 static int srp_alloc_iu_bufs(struct srp_target_port *target)
 935 {
 936         int i;
 937
 938         for (i = 0; i < SRP_RQ_SIZE; ++i) {
 939                 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
 940                                                   target->max_ti_iu_len,
 941                                                   GFP_KERNEL, DMA_FROM_DEVICE);
 942                 if (!target->rx_ring[i])
 943                         goto err;
 944         }
 945
 946         for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
 947                 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
 948                                                   SRP_MAX_IU_LEN,
 949                                                   GFP_KERNEL, DMA_TO_DEVICE);
 950                 if (!target->tx_ring[i])
 951                         goto err;
 952         }
 953
 954         return 0;
 955
 956 err:
 957         for (i = 0; i < SRP_RQ_SIZE; ++i) {
 958                 srp_free_iu(target->srp_host, target->rx_ring[i]);
 959                 target->rx_ring[i] = NULL;
 960         }
 961
 962         for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
 963                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 964                 target->tx_ring[i] = NULL;
 965         }
 966
 967         return -ENOMEM;
 968 }
 969
 970 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
 971                                struct ib_cm_event *event,
 972                                struct srp_target_port *target)
 973 {
 974         struct ib_class_port_info *cpi;
 975         int opcode;
 976
 977         switch (event->param.rej_rcvd.reason) {
 978         case IB_CM_REJ_PORT_CM_REDIRECT:
 979                 cpi = event->param.rej_rcvd.ari;
 980                 target->path.dlid = cpi->redirect_lid;
 981                 target->path.pkey = cpi->redirect_pkey;
 982                 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
 983                 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
 984
 985                 target->status = target->path.dlid ?
 986                         SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
 987                 break;
 988
 989         case IB_CM_REJ_PORT_REDIRECT:
 990                 if (topspin_workarounds &&
 991                     !memcmp(&target->ioc_guid, topspin_oui, 3)) {
 992                         /*
 993                          * Topspin/Cisco SRP gateways incorrectly send
 994                          * reject reason code 25 when they mean 24
 995                          * (port redirect).
 996                          */
 997                         memcpy(target->path.dgid.raw,
 998                                event->param.rej_rcvd.ari, 16);
 999
1000                         printk(KERN_DEBUG PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
1001                                (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
1002                                (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
1003
1004                         target->status = SRP_PORT_REDIRECT;
1005                 } else {
1006                         printk(KERN_WARNING "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1007                         target->status = -ECONNRESET;
1008                 }
1009                 break;
1010
1011         case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1012                 printk(KERN_WARNING "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1013                 target->status = -ECONNRESET;
1014                 break;
1015
1016         case IB_CM_REJ_CONSUMER_DEFINED:
1017                 opcode = *(u8 *) event->private_data;
1018                 if (opcode == SRP_LOGIN_REJ) {
1019                         struct srp_login_rej *rej = event->private_data;
1020                         u32 reason = be32_to_cpu(rej->reason);
1021
1022                         if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1023                                 printk(KERN_WARNING PFX
1024                                        "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1025                         else
1026                                 printk(KERN_WARNING PFX
1027                                        "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1028                 } else
1029                         printk(KERN_WARNING "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1030                                " opcode 0x%02x\n", opcode);
1031                 target->status = -ECONNRESET;
1032                 break;
1033
1034         default:
1035                 printk(KERN_WARNING "  REJ reason 0x%x\n",
1036                        event->param.rej_rcvd.reason);
1037                 target->status = -ECONNRESET;
1038         }
1039 }
1040
1041 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1042 {
1043         struct srp_target_port *target = cm_id->context;
1044         struct ib_qp_attr *qp_attr = NULL;
1045         int attr_mask = 0;
1046         int comp = 0;
1047         int opcode = 0;
1048
1049         switch (event->event) {
1050         case IB_CM_REQ_ERROR:
1051                 printk(KERN_DEBUG PFX "Sending CM REQ failed\n");
1052                 comp = 1;
1053                 target->status = -ECONNRESET;
1054                 break;
1055
1056         case IB_CM_REP_RECEIVED:
1057                 comp = 1;
1058                 opcode = *(u8 *) event->private_data;
1059
1060                 if (opcode == SRP_LOGIN_RSP) {
1061                         struct srp_login_rsp *rsp = event->private_data;
1062
1063                         target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1064                         target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1065
1066                         target->scsi_host->can_queue = min(target->req_lim,
1067                                                            target->scsi_host->can_queue);
1068                 } else {
1069                         printk(KERN_WARNING PFX "Unhandled RSP opcode %#x\n", opcode);
1070                         target->status = -ECONNRESET;
1071                         break;
1072                 }
1073
1074                 target->status = srp_alloc_iu_bufs(target);
1075                 if (target->status)
1076                         break;
1077
1078                 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1079                 if (!qp_attr) {
1080                         target->status = -ENOMEM;
1081                         break;
1082                 }
1083
1084                 qp_attr->qp_state = IB_QPS_RTR;
1085                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1086                 if (target->status)
1087                         break;
1088
1089                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1090                 if (target->status)
1091                         break;
1092
1093                 target->status = srp_post_recv(target);
1094                 if (target->status)
1095                         break;
1096
1097                 qp_attr->qp_state = IB_QPS_RTS;
1098                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1099                 if (target->status)
1100                         break;
1101
1102                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1103                 if (target->status)
1104                         break;
1105
1106                 target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1107                 if (target->status)
1108                         break;
1109
1110                 break;
1111
1112         case IB_CM_REJ_RECEIVED:
1113                 printk(KERN_DEBUG PFX "REJ received\n");
1114                 comp = 1;
1115
1116                 srp_cm_rej_handler(cm_id, event, target);
1117                 break;
1118
1119         case IB_CM_MRA_RECEIVED:
1120                 printk(KERN_ERR PFX "MRA received\n");
1121                 break;
1122
1123         case IB_CM_DREP_RECEIVED:
1124                 break;
1125
1126         case IB_CM_TIMEWAIT_EXIT:
1127                 printk(KERN_ERR PFX "connection closed\n");
1128
1129                 comp = 1;
1130                 target->status = 0;
1131                 break;
1132
1133         default:
1134                 printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
1135                 break;
1136         }
1137
1138         if (comp)
1139                 complete(&target->done);
1140
1141         kfree(qp_attr);
1142
1143         return 0;
1144 }
1145
1146 static int srp_send_tsk_mgmt(struct scsi_cmnd *scmnd, u8 func)
1147 {
1148         struct srp_target_port *target = host_to_target(scmnd->device->host);
1149         struct srp_request *req;
1150         struct srp_iu *iu;
1151         struct srp_tsk_mgmt *tsk_mgmt;
1152         int req_index;
1153         int ret = FAILED;
1154
1155         spin_lock_irq(target->scsi_host->host_lock);
1156
1157         if (target->state == SRP_TARGET_DEAD ||
1158             target->state == SRP_TARGET_REMOVED) {
1159                 scmnd->result = DID_BAD_TARGET << 16;
1160                 goto out;
1161         }
1162
1163         if (scmnd->host_scribble == (void *) -1L)
1164                 goto out;
1165
1166         req_index = (long) scmnd->host_scribble;
1167         printk(KERN_ERR "Abort for req_index %d\n", req_index);
1168
1169         req = &target->req_ring[req_index];
1170         init_completion(&req->done);
1171
1172         iu = __srp_get_tx_iu(target);
1173         if (!iu)
1174                 goto out;
1175
1176         tsk_mgmt = iu->buf;
1177         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1178
1179         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1180         tsk_mgmt->lun           = cpu_to_be64((u64) scmnd->device->lun << 48);
1181         tsk_mgmt->tag           = req_index | SRP_TAG_TSK_MGMT;
1182         tsk_mgmt->tsk_mgmt_func = func;
1183         tsk_mgmt->task_tag      = req_index;
1184
1185         if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1186                 goto out;
1187
1188         req->tsk_mgmt = iu;
1189
1190         spin_unlock_irq(target->scsi_host->host_lock);
1191         if (!wait_for_completion_timeout(&req->done,
1192                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1193                 return FAILED;
1194         spin_lock_irq(target->scsi_host->host_lock);
1195
1196         if (req->cmd_done) {
1197                 srp_remove_req(target, req, req_index);
1198                 scmnd->scsi_done(scmnd);
1199         } else if (!req->tsk_status) {
1200                 srp_remove_req(target, req, req_index);
1201                 scmnd->result = DID_ABORT << 16;
1202                 ret = SUCCESS;
1203         }
1204
1205 out:
1206         spin_unlock_irq(target->scsi_host->host_lock);
1207         return ret;
1208 }
1209
1210 static int srp_abort(struct scsi_cmnd *scmnd)
1211 {
1212         printk(KERN_ERR "SRP abort called\n");
1213
1214         return srp_send_tsk_mgmt(scmnd, SRP_TSK_ABORT_TASK);
1215 }
1216
1217 static int srp_reset_device(struct scsi_cmnd *scmnd)
1218 {
1219         printk(KERN_ERR "SRP reset_device called\n");
1220
1221         return srp_send_tsk_mgmt(scmnd, SRP_TSK_LUN_RESET);
1222 }
1223
1224 static int srp_reset_host(struct scsi_cmnd *scmnd)
1225 {
1226         struct srp_target_port *target = host_to_target(scmnd->device->host);
1227         int ret = FAILED;
1228
1229         printk(KERN_ERR PFX "SRP reset_host called\n");
1230
1231         if (!srp_reconnect_target(target))
1232                 ret = SUCCESS;
1233
1234         return ret;
1235 }
1236
1237 static ssize_t show_id_ext(struct class_device *cdev, char *buf)
1238 {
1239         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1240
1241         if (target->state == SRP_TARGET_DEAD ||
1242             target->state == SRP_TARGET_REMOVED)
1243                 return -ENODEV;
1244
1245         return sprintf(buf, "0x%016llx\n",
1246                        (unsigned long long) be64_to_cpu(target->id_ext));
1247 }
1248
1249 static ssize_t show_ioc_guid(struct class_device *cdev, char *buf)
1250 {
1251         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1252
1253         if (target->state == SRP_TARGET_DEAD ||
1254             target->state == SRP_TARGET_REMOVED)
1255                 return -ENODEV;
1256
1257         return sprintf(buf, "0x%016llx\n",
1258                        (unsigned long long) be64_to_cpu(target->ioc_guid));
1259 }
1260
1261 static ssize_t show_service_id(struct class_device *cdev, char *buf)
1262 {
1263         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1264
1265         if (target->state == SRP_TARGET_DEAD ||
1266             target->state == SRP_TARGET_REMOVED)
1267                 return -ENODEV;
1268
1269         return sprintf(buf, "0x%016llx\n",
1270                        (unsigned long long) be64_to_cpu(target->service_id));
1271 }
1272
1273 static ssize_t show_pkey(struct class_device *cdev, char *buf)
1274 {
1275         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1276
1277         if (target->state == SRP_TARGET_DEAD ||
1278             target->state == SRP_TARGET_REMOVED)
1279                 return -ENODEV;
1280
1281         return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1282 }
1283
1284 static ssize_t show_dgid(struct class_device *cdev, char *buf)
1285 {
1286         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1287
1288         if (target->state == SRP_TARGET_DEAD ||
1289             target->state == SRP_TARGET_REMOVED)
1290                 return -ENODEV;
1291
1292         return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1293                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
1294                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
1295                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
1296                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
1297                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
1298                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
1299                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
1300                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
1301 }
1302
1303 static CLASS_DEVICE_ATTR(id_ext,        S_IRUGO, show_id_ext,           NULL);
1304 static CLASS_DEVICE_ATTR(ioc_guid,      S_IRUGO, show_ioc_guid,         NULL);
1305 static CLASS_DEVICE_ATTR(service_id,    S_IRUGO, show_service_id,       NULL);
1306 static CLASS_DEVICE_ATTR(pkey,          S_IRUGO, show_pkey,             NULL);
1307 static CLASS_DEVICE_ATTR(dgid,          S_IRUGO, show_dgid,             NULL);
1308
1309 static struct class_device_attribute *srp_host_attrs[] = {
1310         &class_device_attr_id_ext,
1311         &class_device_attr_ioc_guid,
1312         &class_device_attr_service_id,
1313         &class_device_attr_pkey,
1314         &class_device_attr_dgid,
1315         NULL
1316 };
1317
1318 static struct scsi_host_template srp_template = {
1319         .module                         = THIS_MODULE,
1320         .name                           = DRV_NAME,
1321         .info                           = srp_target_info,
1322         .queuecommand                   = srp_queuecommand,
1323         .eh_abort_handler               = srp_abort,
1324         .eh_device_reset_handler        = srp_reset_device,
1325         .eh_host_reset_handler          = srp_reset_host,
1326         .can_queue                      = SRP_SQ_SIZE,
1327         .this_id                        = -1,
1328         .sg_tablesize                   = SRP_MAX_INDIRECT,
1329         .cmd_per_lun                    = SRP_SQ_SIZE,
1330         .use_clustering                 = ENABLE_CLUSTERING,
1331         .shost_attrs                    = srp_host_attrs
1332 };
1333
1334 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1335 {
1336         sprintf(target->target_name, "SRP.T10:%016llX",
1337                  (unsigned long long) be64_to_cpu(target->id_ext));
1338
1339         if (scsi_add_host(target->scsi_host, host->dev->dma_device))
1340                 return -ENODEV;
1341
1342         mutex_lock(&host->target_mutex);
1343         list_add_tail(&target->list, &host->target_list);
1344         mutex_unlock(&host->target_mutex);
1345
1346         target->state = SRP_TARGET_LIVE;
1347
1348         /* XXX: are we supposed to have a definition of SCAN_WILD_CARD ?? */
1349         scsi_scan_target(&target->scsi_host->shost_gendev,
1350                          0, target->scsi_id, ~0, 0);
1351
1352         return 0;
1353 }
1354
1355 static void srp_release_class_dev(struct class_device *class_dev)
1356 {
1357         struct srp_host *host =
1358                 container_of(class_dev, struct srp_host, class_dev);
1359
1360         complete(&host->released);
1361 }
1362
1363 static struct class srp_class = {
1364         .name    = "infiniband_srp",
1365         .release = srp_release_class_dev
1366 };
1367
1368 /*
1369  * Target ports are added by writing
1370  *
1371  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1372  *     pkey=<P_Key>,service_id=<service ID>
1373  *
1374  * to the add_target sysfs attribute.
1375  */
1376 enum {
1377         SRP_OPT_ERR             = 0,
1378         SRP_OPT_ID_EXT          = 1 << 0,
1379         SRP_OPT_IOC_GUID        = 1 << 1,
1380         SRP_OPT_DGID            = 1 << 2,
1381         SRP_OPT_PKEY            = 1 << 3,
1382         SRP_OPT_SERVICE_ID      = 1 << 4,
1383         SRP_OPT_MAX_SECT        = 1 << 5,
1384         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1385                                    SRP_OPT_IOC_GUID     |
1386                                    SRP_OPT_DGID         |
1387                                    SRP_OPT_PKEY         |
1388                                    SRP_OPT_SERVICE_ID),
1389 };
1390
1391 static match_table_t srp_opt_tokens = {
1392         { SRP_OPT_ID_EXT,       "id_ext=%s"     },
1393         { SRP_OPT_IOC_GUID,     "ioc_guid=%s"   },
1394         { SRP_OPT_DGID,         "dgid=%s"       },
1395         { SRP_OPT_PKEY,         "pkey=%x"       },
1396         { SRP_OPT_SERVICE_ID,   "service_id=%s" },
1397         { SRP_OPT_MAX_SECT,     "max_sect=%d"   },
1398         { SRP_OPT_ERR,          NULL            }
1399 };
1400
1401 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1402 {
1403         char *options, *sep_opt;
1404         char *p;
1405         char dgid[3];
1406         substring_t args[MAX_OPT_ARGS];
1407         int opt_mask = 0;
1408         int token;
1409         int ret = -EINVAL;
1410         int i;
1411
1412         options = kstrdup(buf, GFP_KERNEL);
1413         if (!options)
1414                 return -ENOMEM;
1415
1416         sep_opt = options;
1417         while ((p = strsep(&sep_opt, ",")) != NULL) {
1418                 if (!*p)
1419                         continue;
1420
1421                 token = match_token(p, srp_opt_tokens, args);
1422                 opt_mask |= token;
1423
1424                 switch (token) {
1425                 case SRP_OPT_ID_EXT:
1426                         p = match_strdup(args);
1427                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1428                         kfree(p);
1429                         break;
1430
1431                 case SRP_OPT_IOC_GUID:
1432                         p = match_strdup(args);
1433                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1434                         kfree(p);
1435                         break;
1436
1437                 case SRP_OPT_DGID:
1438                         p = match_strdup(args);
1439                         if (strlen(p) != 32) {
1440                                 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1441                                 kfree(p);
1442                                 goto out;
1443                         }
1444
1445                         for (i = 0; i < 16; ++i) {
1446                                 strlcpy(dgid, p + i * 2, 3);
1447                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1448                         }
1449                         kfree(p);
1450                         break;
1451
1452                 case SRP_OPT_PKEY:
1453                         if (match_hex(args, &token)) {
1454                                 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1455                                 goto out;
1456                         }
1457                         target->path.pkey = cpu_to_be16(token);
1458                         break;
1459
1460                 case SRP_OPT_SERVICE_ID:
1461                         p = match_strdup(args);
1462                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1463                         kfree(p);
1464                         break;
1465
1466                 case SRP_OPT_MAX_SECT:
1467                         if (match_int(args, &token)) {
1468                                 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1469                                 goto out;
1470                         }
1471                         target->scsi_host->max_sectors = token;
1472                         break;
1473
1474                 default:
1475                         printk(KERN_WARNING PFX "unknown parameter or missing value "
1476                                "'%s' in target creation request\n", p);
1477                         goto out;
1478                 }
1479         }
1480
1481         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1482                 ret = 0;
1483         else
1484                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1485                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1486                             !(srp_opt_tokens[i].token & opt_mask))
1487                                 printk(KERN_WARNING PFX "target creation request is "
1488                                        "missing parameter '%s'\n",
1489                                        srp_opt_tokens[i].pattern);
1490
1491 out:
1492         kfree(options);
1493         return ret;
1494 }
1495
1496 static ssize_t srp_create_target(struct class_device *class_dev,
1497                                  const char *buf, size_t count)
1498 {
1499         struct srp_host *host =
1500                 container_of(class_dev, struct srp_host, class_dev);
1501         struct Scsi_Host *target_host;
1502         struct srp_target_port *target;
1503         int ret;
1504         int i;
1505
1506         target_host = scsi_host_alloc(&srp_template,
1507                                       sizeof (struct srp_target_port));
1508         if (!target_host)
1509                 return -ENOMEM;
1510
1511         target_host->max_lun = SRP_MAX_LUN;
1512
1513         target = host_to_target(target_host);
1514         memset(target, 0, sizeof *target);
1515
1516         target->scsi_host  = target_host;
1517         target->srp_host   = host;
1518
1519         INIT_WORK(&target->work, srp_reconnect_work, target);
1520
1521         for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
1522                 target->req_ring[i].next = i + 1;
1523         target->req_ring[SRP_SQ_SIZE - 1].next = -1;
1524         INIT_LIST_HEAD(&target->req_queue);
1525
1526         ret = srp_parse_options(buf, target);
1527         if (ret)
1528                 goto err;
1529
1530         ib_get_cached_gid(host->dev, host->port, 0, &target->path.sgid);
1531
1532         printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1533                "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1534                (unsigned long long) be64_to_cpu(target->id_ext),
1535                (unsigned long long) be64_to_cpu(target->ioc_guid),
1536                be16_to_cpu(target->path.pkey),
1537                (unsigned long long) be64_to_cpu(target->service_id),
1538                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
1539                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
1540                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
1541                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
1542                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
1543                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
1544                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
1545                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
1546
1547         ret = srp_create_target_ib(target);
1548         if (ret)
1549                 goto err;
1550
1551         target->cm_id = ib_create_cm_id(host->dev, srp_cm_handler, target);
1552         if (IS_ERR(target->cm_id)) {
1553                 ret = PTR_ERR(target->cm_id);
1554                 goto err_free;
1555         }
1556
1557         ret = srp_connect_target(target);
1558         if (ret) {
1559                 printk(KERN_ERR PFX "Connection failed\n");
1560                 goto err_cm_id;
1561         }
1562
1563         ret = srp_add_target(host, target);
1564         if (ret)
1565                 goto err_disconnect;
1566
1567         return count;
1568
1569 err_disconnect:
1570         srp_disconnect_target(target);
1571
1572 err_cm_id:
1573         ib_destroy_cm_id(target->cm_id);
1574
1575 err_free:
1576         srp_free_target_ib(target);
1577
1578 err:
1579         scsi_host_put(target_host);
1580
1581         return ret;
1582 }
1583
1584 static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1585
1586 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
1587 {
1588         struct srp_host *host =
1589                 container_of(class_dev, struct srp_host, class_dev);
1590
1591         return sprintf(buf, "%s\n", host->dev->name);
1592 }
1593
1594 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1595
1596 static ssize_t show_port(struct class_device *class_dev, char *buf)
1597 {
1598         struct srp_host *host =
1599                 container_of(class_dev, struct srp_host, class_dev);
1600
1601         return sprintf(buf, "%d\n", host->port);
1602 }
1603
1604 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1605
1606 static struct srp_host *srp_add_port(struct ib_device *device, u8 port)
1607 {
1608         struct srp_host *host;
1609
1610         host = kzalloc(sizeof *host, GFP_KERNEL);
1611         if (!host)
1612                 return NULL;
1613
1614         INIT_LIST_HEAD(&host->target_list);
1615         mutex_init(&host->target_mutex);
1616         init_completion(&host->released);
1617         host->dev  = device;
1618         host->port = port;
1619
1620         host->initiator_port_id[7] = port;
1621         memcpy(host->initiator_port_id + 8, &device->node_guid, 8);
1622
1623         host->pd   = ib_alloc_pd(device);
1624         if (IS_ERR(host->pd))
1625                 goto err_free;
1626
1627         host->mr   = ib_get_dma_mr(host->pd,
1628                                    IB_ACCESS_LOCAL_WRITE |
1629                                    IB_ACCESS_REMOTE_READ |
1630                                    IB_ACCESS_REMOTE_WRITE);
1631         if (IS_ERR(host->mr))
1632                 goto err_pd;
1633
1634         host->class_dev.class = &srp_class;
1635         host->class_dev.dev   = device->dma_device;
1636         snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
1637                  device->name, port);
1638
1639         if (class_device_register(&host->class_dev))
1640                 goto err_mr;
1641         if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
1642                 goto err_class;
1643         if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
1644                 goto err_class;
1645         if (class_device_create_file(&host->class_dev, &class_device_attr_port))
1646                 goto err_class;
1647
1648         return host;
1649
1650 err_class:
1651         class_device_unregister(&host->class_dev);
1652
1653 err_mr:
1654         ib_dereg_mr(host->mr);
1655
1656 err_pd:
1657         ib_dealloc_pd(host->pd);
1658
1659 err_free:
1660         kfree(host);
1661
1662         return NULL;
1663 }
1664
1665 static void srp_add_one(struct ib_device *device)
1666 {
1667         struct list_head *dev_list;
1668         struct srp_host *host;
1669         int s, e, p;
1670
1671         dev_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
1672         if (!dev_list)
1673                 return;
1674
1675         INIT_LIST_HEAD(dev_list);
1676
1677         if (device->node_type == IB_NODE_SWITCH) {
1678                 s = 0;
1679                 e = 0;
1680         } else {
1681                 s = 1;
1682                 e = device->phys_port_cnt;
1683         }
1684
1685         for (p = s; p <= e; ++p) {
1686                 host = srp_add_port(device, p);
1687                 if (host)
1688                         list_add_tail(&host->list, dev_list);
1689         }
1690
1691         ib_set_client_data(device, &srp_client, dev_list);
1692 }
1693
1694 static void srp_remove_one(struct ib_device *device)
1695 {
1696         struct list_head *dev_list;
1697         struct srp_host *host, *tmp_host;
1698         LIST_HEAD(target_list);
1699         struct srp_target_port *target, *tmp_target;
1700         unsigned long flags;
1701
1702         dev_list = ib_get_client_data(device, &srp_client);
1703
1704         list_for_each_entry_safe(host, tmp_host, dev_list, list) {
1705                 class_device_unregister(&host->class_dev);
1706                 /*
1707                  * Wait for the sysfs entry to go away, so that no new
1708                  * target ports can be created.
1709                  */
1710                 wait_for_completion(&host->released);
1711
1712                 /*
1713                  * Mark all target ports as removed, so we stop queueing
1714                  * commands and don't try to reconnect.
1715                  */
1716                 mutex_lock(&host->target_mutex);
1717                 list_for_each_entry_safe(target, tmp_target,
1718                                          &host->target_list, list) {
1719                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
1720                         if (target->state != SRP_TARGET_REMOVED)
1721                                 target->state = SRP_TARGET_REMOVED;
1722                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
1723                 }
1724                 mutex_unlock(&host->target_mutex);
1725
1726                 /*
1727                  * Wait for any reconnection tasks that may have
1728                  * started before we marked our target ports as
1729                  * removed, and any target port removal tasks.
1730                  */
1731                 flush_scheduled_work();
1732
1733                 list_for_each_entry_safe(target, tmp_target,
1734                                          &host->target_list, list) {
1735                         scsi_remove_host(target->scsi_host);
1736                         srp_disconnect_target(target);
1737                         ib_destroy_cm_id(target->cm_id);
1738                         srp_free_target_ib(target);
1739                         scsi_host_put(target->scsi_host);
1740                 }
1741
1742                 ib_dereg_mr(host->mr);
1743                 ib_dealloc_pd(host->pd);
1744                 kfree(host);
1745         }
1746
1747         kfree(dev_list);
1748 }
1749
1750 static int __init srp_init_module(void)
1751 {
1752         int ret;
1753
1754         ret = class_register(&srp_class);
1755         if (ret) {
1756                 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
1757                 return ret;
1758         }
1759
1760         ret = ib_register_client(&srp_client);
1761         if (ret) {
1762                 printk(KERN_ERR PFX "couldn't register IB client\n");
1763                 class_unregister(&srp_class);
1764                 return ret;
1765         }
1766
1767         return 0;
1768 }
1769
1770 static void __exit srp_cleanup_module(void)
1771 {
1772         ib_unregister_client(&srp_client);
1773         class_unregister(&srp_class);
1774 }
1775
1776 module_init(srp_init_module);
1777 module_exit(srp_cleanup_module);