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  = (struct scatterlist *) scmnd->request_buffer;
 611         } else {
 612                 nents = 1;
 613                 scat  = (struct scatterlist *) scmnd->request_buffer;
 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_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
 621 {
 622         struct srp_request *req;
 623         struct scsi_cmnd *scmnd;
 624         unsigned long flags;
 625         s32 delta;
 626
 627         delta = (s32) be32_to_cpu(rsp->req_lim_delta);
 628
 629         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 630
 631         target->req_lim += delta;
 632
 633         req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
 634
 635         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
 636                 if (be32_to_cpu(rsp->resp_data_len) < 4)
 637                         req->tsk_status = -1;
 638                 else
 639                         req->tsk_status = rsp->data[3];
 640                 complete(&req->done);
 641         } else {
 642                 scmnd         = req->scmnd;
 643                 if (!scmnd)
 644                         printk(KERN_ERR "Null scmnd for RSP w/tag %016llx\n",
 645                                (unsigned long long) rsp->tag);
 646                 scmnd->result = rsp->status;
 647
 648                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
 649                         memcpy(scmnd->sense_buffer, rsp->data +
 650                                be32_to_cpu(rsp->resp_data_len),
 651                                min_t(int, be32_to_cpu(rsp->sense_data_len),
 652                                      SCSI_SENSE_BUFFERSIZE));
 653                 }
 654
 655                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
 656                         scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
 657                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
 658                         scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
 659
 660                 srp_unmap_data(scmnd, target, req);
 661
 662                 if (!req->tsk_mgmt) {
 663                         req->scmnd = NULL;
 664                         scmnd->host_scribble = (void *) -1L;
 665                         scmnd->scsi_done(scmnd);
 666
 667                         list_del(&req->list);
 668                         req->next = target->req_head;
 669                         target->req_head = rsp->tag & ~SRP_TAG_TSK_MGMT;
 670                 } else
 671                         req->cmd_done = 1;
 672         }
 673
 674         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 675 }
 676
 677 static void srp_reconnect_work(void *target_ptr)
 678 {
 679         struct srp_target_port *target = target_ptr;
 680
 681         srp_reconnect_target(target);
 682 }
 683
 684 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 685 {
 686         struct srp_iu *iu;
 687         u8 opcode;
 688
 689         iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
 690
 691         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 692                                 target->max_ti_iu_len, DMA_FROM_DEVICE);
 693
 694         opcode = *(u8 *) iu->buf;
 695
 696         if (0) {
 697                 int i;
 698
 699                 printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
 700
 701                 for (i = 0; i < wc->byte_len; ++i) {
 702                         if (i % 8 == 0)
 703                                 printk(KERN_ERR "  [%02x] ", i);
 704                         printk(" %02x", ((u8 *) iu->buf)[i]);
 705                         if ((i + 1) % 8 == 0)
 706                                 printk("\n");
 707                 }
 708
 709                 if (wc->byte_len % 8)
 710                         printk("\n");
 711         }
 712
 713         switch (opcode) {
 714         case SRP_RSP:
 715                 srp_process_rsp(target, iu->buf);
 716                 break;
 717
 718         case SRP_T_LOGOUT:
 719                 /* XXX Handle target logout */
 720                 printk(KERN_WARNING PFX "Got target logout request\n");
 721                 break;
 722
 723         default:
 724                 printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
 725                 break;
 726         }
 727
 728         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 729                                    target->max_ti_iu_len, DMA_FROM_DEVICE);
 730 }
 731
 732 static void srp_completion(struct ib_cq *cq, void *target_ptr)
 733 {
 734         struct srp_target_port *target = target_ptr;
 735         struct ib_wc wc;
 736         unsigned long flags;
 737
 738         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
 739         while (ib_poll_cq(cq, 1, &wc) > 0) {
 740                 if (wc.status) {
 741                         printk(KERN_ERR PFX "failed %s status %d\n",
 742                                wc.wr_id & SRP_OP_RECV ? "receive" : "send",
 743                                wc.status);
 744                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 745                         if (target->state == SRP_TARGET_LIVE)
 746                                 schedule_work(&target->work);
 747                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 748                         break;
 749                 }
 750
 751                 if (wc.wr_id & SRP_OP_RECV)
 752                         srp_handle_recv(target, &wc);
 753                 else
 754                         ++target->tx_tail;
 755         }
 756 }
 757
 758 static int __srp_post_recv(struct srp_target_port *target)
 759 {
 760         struct srp_iu *iu;
 761         struct ib_sge list;
 762         struct ib_recv_wr wr, *bad_wr;
 763         unsigned int next;
 764         int ret;
 765
 766         next     = target->rx_head & (SRP_RQ_SIZE - 1);
 767         wr.wr_id = next | SRP_OP_RECV;
 768         iu       = target->rx_ring[next];
 769
 770         list.addr   = iu->dma;
 771         list.length = iu->size;
 772         list.lkey   = target->srp_host->mr->lkey;
 773
 774         wr.next     = NULL;
 775         wr.sg_list  = &list;
 776         wr.num_sge  = 1;
 777
 778         ret = ib_post_recv(target->qp, &wr, &bad_wr);
 779         if (!ret)
 780                 ++target->rx_head;
 781
 782         return ret;
 783 }
 784
 785 static int srp_post_recv(struct srp_target_port *target)
 786 {
 787         unsigned long flags;
 788         int ret;
 789
 790         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 791         ret = __srp_post_recv(target);
 792         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 793
 794         return ret;
 795 }
 796
 797 /*
 798  * Must be called with target->scsi_host->host_lock held to protect
 799  * req_lim and tx_head.  Lock cannot be dropped between call here and
 800  * call to __srp_post_send().
 801  */
 802 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
 803 {
 804         if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
 805                 return NULL;
 806
 807         if (unlikely(target->req_lim < 1)) {
 808                 if (printk_ratelimit())
 809                         printk(KERN_DEBUG PFX "Target has req_lim %d\n",
 810                                target->req_lim);
 811                 return NULL;
 812         }
 813
 814         return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
 815 }
 816
 817 /*
 818  * Must be called with target->scsi_host->host_lock held to protect
 819  * req_lim and tx_head.
 820  */
 821 static int __srp_post_send(struct srp_target_port *target,
 822                            struct srp_iu *iu, int len)
 823 {
 824         struct ib_sge list;
 825         struct ib_send_wr wr, *bad_wr;
 826         int ret = 0;
 827
 828         list.addr   = iu->dma;
 829         list.length = len;
 830         list.lkey   = target->srp_host->mr->lkey;
 831
 832         wr.next       = NULL;
 833         wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
 834         wr.sg_list    = &list;
 835         wr.num_sge    = 1;
 836         wr.opcode     = IB_WR_SEND;
 837         wr.send_flags = IB_SEND_SIGNALED;
 838
 839         ret = ib_post_send(target->qp, &wr, &bad_wr);
 840
 841         if (!ret) {
 842                 ++target->tx_head;
 843                 --target->req_lim;
 844         }
 845
 846         return ret;
 847 }
 848
 849 static int srp_queuecommand(struct scsi_cmnd *scmnd,
 850                             void (*done)(struct scsi_cmnd *))
 851 {
 852         struct srp_target_port *target = host_to_target(scmnd->device->host);
 853         struct srp_request *req;
 854         struct srp_iu *iu;
 855         struct srp_cmd *cmd;
 856         long req_index;
 857         int len;
 858
 859         if (target->state == SRP_TARGET_CONNECTING)
 860                 goto err;
 861
 862         if (target->state == SRP_TARGET_DEAD ||
 863             target->state == SRP_TARGET_REMOVED) {
 864                 scmnd->result = DID_BAD_TARGET << 16;
 865                 done(scmnd);
 866                 return 0;
 867         }
 868
 869         iu = __srp_get_tx_iu(target);
 870         if (!iu)
 871                 goto err;
 872
 873         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 874                                 SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 875
 876         req_index = target->req_head;
 877
 878         scmnd->scsi_done     = done;
 879         scmnd->result        = 0;
 880         scmnd->host_scribble = (void *) req_index;
 881
 882         cmd = iu->buf;
 883         memset(cmd, 0, sizeof *cmd);
 884
 885         cmd->opcode = SRP_CMD;
 886         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
 887         cmd->tag    = req_index;
 888         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
 889
 890         req = &target->req_ring[req_index];
 891
 892         req->scmnd    = scmnd;
 893         req->cmd      = iu;
 894         req->cmd_done = 0;
 895         req->tsk_mgmt = NULL;
 896
 897         len = srp_map_data(scmnd, target, req);
 898         if (len < 0) {
 899                 printk(KERN_ERR PFX "Failed to map data\n");
 900                 goto err;
 901         }
 902
 903         if (__srp_post_recv(target)) {
 904                 printk(KERN_ERR PFX "Recv failed\n");
 905                 goto err_unmap;
 906         }
 907
 908         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 909                                    SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 910
 911         if (__srp_post_send(target, iu, len)) {
 912                 printk(KERN_ERR PFX "Send failed\n");
 913                 goto err_unmap;
 914         }
 915
 916         target->req_head = req->next;
 917         list_add_tail(&req->list, &target->req_queue);
 918
 919         return 0;
 920
 921 err_unmap:
 922         srp_unmap_data(scmnd, target, req);
 923
 924 err:
 925         return SCSI_MLQUEUE_HOST_BUSY;
 926 }
 927
 928 static int srp_alloc_iu_bufs(struct srp_target_port *target)
 929 {
 930         int i;
 931
 932         for (i = 0; i < SRP_RQ_SIZE; ++i) {
 933                 target->rx_ring[i] = srp_alloc_iu(target->srp_host,
 934                                                   target->max_ti_iu_len,
 935                                                   GFP_KERNEL, DMA_FROM_DEVICE);
 936                 if (!target->rx_ring[i])
 937                         goto err;
 938         }
 939
 940         for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
 941                 target->tx_ring[i] = srp_alloc_iu(target->srp_host,
 942                                                   SRP_MAX_IU_LEN,
 943                                                   GFP_KERNEL, DMA_TO_DEVICE);
 944                 if (!target->tx_ring[i])
 945                         goto err;
 946         }
 947
 948         return 0;
 949
 950 err:
 951         for (i = 0; i < SRP_RQ_SIZE; ++i) {
 952                 srp_free_iu(target->srp_host, target->rx_ring[i]);
 953                 target->rx_ring[i] = NULL;
 954         }
 955
 956         for (i = 0; i < SRP_SQ_SIZE + 1; ++i) {
 957                 srp_free_iu(target->srp_host, target->tx_ring[i]);
 958                 target->tx_ring[i] = NULL;
 959         }
 960
 961         return -ENOMEM;
 962 }
 963
 964 static void srp_cm_rej_handler(struct ib_cm_id *cm_id,
 965                                struct ib_cm_event *event,
 966                                struct srp_target_port *target)
 967 {
 968         struct ib_class_port_info *cpi;
 969         int opcode;
 970
 971         switch (event->param.rej_rcvd.reason) {
 972         case IB_CM_REJ_PORT_CM_REDIRECT:
 973                 cpi = event->param.rej_rcvd.ari;
 974                 target->path.dlid = cpi->redirect_lid;
 975                 target->path.pkey = cpi->redirect_pkey;
 976                 cm_id->remote_cm_qpn = be32_to_cpu(cpi->redirect_qp) & 0x00ffffff;
 977                 memcpy(target->path.dgid.raw, cpi->redirect_gid, 16);
 978
 979                 target->status = target->path.dlid ?
 980                         SRP_DLID_REDIRECT : SRP_PORT_REDIRECT;
 981                 break;
 982
 983         case IB_CM_REJ_PORT_REDIRECT:
 984                 if (topspin_workarounds &&
 985                     !memcmp(&target->ioc_guid, topspin_oui, 3)) {
 986                         /*
 987                          * Topspin/Cisco SRP gateways incorrectly send
 988                          * reject reason code 25 when they mean 24
 989                          * (port redirect).
 990                          */
 991                         memcpy(target->path.dgid.raw,
 992                                event->param.rej_rcvd.ari, 16);
 993
 994                         printk(KERN_DEBUG PFX "Topspin/Cisco redirect to target port GID %016llx%016llx\n",
 995                                (unsigned long long) be64_to_cpu(target->path.dgid.global.subnet_prefix),
 996                                (unsigned long long) be64_to_cpu(target->path.dgid.global.interface_id));
 997
 998                         target->status = SRP_PORT_REDIRECT;
 999                 } else {
1000                         printk(KERN_WARNING "  REJ reason: IB_CM_REJ_PORT_REDIRECT\n");
1001                         target->status = -ECONNRESET;
1002                 }
1003                 break;
1004
1005         case IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID:
1006                 printk(KERN_WARNING "  REJ reason: IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID\n");
1007                 target->status = -ECONNRESET;
1008                 break;
1009
1010         case IB_CM_REJ_CONSUMER_DEFINED:
1011                 opcode = *(u8 *) event->private_data;
1012                 if (opcode == SRP_LOGIN_REJ) {
1013                         struct srp_login_rej *rej = event->private_data;
1014                         u32 reason = be32_to_cpu(rej->reason);
1015
1016                         if (reason == SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE)
1017                                 printk(KERN_WARNING PFX
1018                                        "SRP_LOGIN_REJ: requested max_it_iu_len too large\n");
1019                         else
1020                                 printk(KERN_WARNING PFX
1021                                        "SRP LOGIN REJECTED, reason 0x%08x\n", reason);
1022                 } else
1023                         printk(KERN_WARNING "  REJ reason: IB_CM_REJ_CONSUMER_DEFINED,"
1024                                " opcode 0x%02x\n", opcode);
1025                 target->status = -ECONNRESET;
1026                 break;
1027
1028         default:
1029                 printk(KERN_WARNING "  REJ reason 0x%x\n",
1030                        event->param.rej_rcvd.reason);
1031                 target->status = -ECONNRESET;
1032         }
1033 }
1034
1035 static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
1036 {
1037         struct srp_target_port *target = cm_id->context;
1038         struct ib_qp_attr *qp_attr = NULL;
1039         int attr_mask = 0;
1040         int comp = 0;
1041         int opcode = 0;
1042
1043         switch (event->event) {
1044         case IB_CM_REQ_ERROR:
1045                 printk(KERN_DEBUG PFX "Sending CM REQ failed\n");
1046                 comp = 1;
1047                 target->status = -ECONNRESET;
1048                 break;
1049
1050         case IB_CM_REP_RECEIVED:
1051                 comp = 1;
1052                 opcode = *(u8 *) event->private_data;
1053
1054                 if (opcode == SRP_LOGIN_RSP) {
1055                         struct srp_login_rsp *rsp = event->private_data;
1056
1057                         target->max_ti_iu_len = be32_to_cpu(rsp->max_ti_iu_len);
1058                         target->req_lim       = be32_to_cpu(rsp->req_lim_delta);
1059
1060                         target->scsi_host->can_queue = min(target->req_lim,
1061                                                            target->scsi_host->can_queue);
1062                 } else {
1063                         printk(KERN_WARNING PFX "Unhandled RSP opcode %#x\n", opcode);
1064                         target->status = -ECONNRESET;
1065                         break;
1066                 }
1067
1068                 target->status = srp_alloc_iu_bufs(target);
1069                 if (target->status)
1070                         break;
1071
1072                 qp_attr = kmalloc(sizeof *qp_attr, GFP_KERNEL);
1073                 if (!qp_attr) {
1074                         target->status = -ENOMEM;
1075                         break;
1076                 }
1077
1078                 qp_attr->qp_state = IB_QPS_RTR;
1079                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1080                 if (target->status)
1081                         break;
1082
1083                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1084                 if (target->status)
1085                         break;
1086
1087                 target->status = srp_post_recv(target);
1088                 if (target->status)
1089                         break;
1090
1091                 qp_attr->qp_state = IB_QPS_RTS;
1092                 target->status = ib_cm_init_qp_attr(cm_id, qp_attr, &attr_mask);
1093                 if (target->status)
1094                         break;
1095
1096                 target->status = ib_modify_qp(target->qp, qp_attr, attr_mask);
1097                 if (target->status)
1098                         break;
1099
1100                 target->status = ib_send_cm_rtu(cm_id, NULL, 0);
1101                 if (target->status)
1102                         break;
1103
1104                 break;
1105
1106         case IB_CM_REJ_RECEIVED:
1107                 printk(KERN_DEBUG PFX "REJ received\n");
1108                 comp = 1;
1109
1110                 srp_cm_rej_handler(cm_id, event, target);
1111                 break;
1112
1113         case IB_CM_MRA_RECEIVED:
1114                 printk(KERN_ERR PFX "MRA received\n");
1115                 break;
1116
1117         case IB_CM_DREP_RECEIVED:
1118                 break;
1119
1120         case IB_CM_TIMEWAIT_EXIT:
1121                 printk(KERN_ERR PFX "connection closed\n");
1122
1123                 comp = 1;
1124                 target->status = 0;
1125                 break;
1126
1127         default:
1128                 printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
1129                 break;
1130         }
1131
1132         if (comp)
1133                 complete(&target->done);
1134
1135         kfree(qp_attr);
1136
1137         return 0;
1138 }
1139
1140 static int srp_send_tsk_mgmt(struct scsi_cmnd *scmnd, u8 func)
1141 {
1142         struct srp_target_port *target = host_to_target(scmnd->device->host);
1143         struct srp_request *req;
1144         struct srp_iu *iu;
1145         struct srp_tsk_mgmt *tsk_mgmt;
1146         int req_index;
1147         int ret = FAILED;
1148
1149         spin_lock_irq(target->scsi_host->host_lock);
1150
1151         if (target->state == SRP_TARGET_DEAD ||
1152             target->state == SRP_TARGET_REMOVED) {
1153                 scmnd->result = DID_BAD_TARGET << 16;
1154                 goto out;
1155         }
1156
1157         if (scmnd->host_scribble == (void *) -1L)
1158                 goto out;
1159
1160         req_index = (long) scmnd->host_scribble;
1161         printk(KERN_ERR "Abort for req_index %d\n", req_index);
1162
1163         req = &target->req_ring[req_index];
1164         init_completion(&req->done);
1165
1166         iu = __srp_get_tx_iu(target);
1167         if (!iu)
1168                 goto out;
1169
1170         tsk_mgmt = iu->buf;
1171         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1172
1173         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1174         tsk_mgmt->lun           = cpu_to_be64((u64) scmnd->device->lun << 48);
1175         tsk_mgmt->tag           = req_index | SRP_TAG_TSK_MGMT;
1176         tsk_mgmt->tsk_mgmt_func = func;
1177         tsk_mgmt->task_tag      = req_index;
1178
1179         if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1180                 goto out;
1181
1182         req->tsk_mgmt = iu;
1183
1184         spin_unlock_irq(target->scsi_host->host_lock);
1185         if (!wait_for_completion_timeout(&req->done,
1186                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1187                 return FAILED;
1188         spin_lock_irq(target->scsi_host->host_lock);
1189
1190         if (req->cmd_done) {
1191                 list_del(&req->list);
1192                 req->next = target->req_head;
1193                 target->req_head = req_index;
1194
1195                 scmnd->scsi_done(scmnd);
1196         } else if (!req->tsk_status) {
1197                 scmnd->result = DID_ABORT << 16;
1198                 ret = SUCCESS;
1199         }
1200
1201 out:
1202         spin_unlock_irq(target->scsi_host->host_lock);
1203         return ret;
1204 }
1205
1206 static int srp_abort(struct scsi_cmnd *scmnd)
1207 {
1208         printk(KERN_ERR "SRP abort called\n");
1209
1210         return srp_send_tsk_mgmt(scmnd, SRP_TSK_ABORT_TASK);
1211 }
1212
1213 static int srp_reset_device(struct scsi_cmnd *scmnd)
1214 {
1215         printk(KERN_ERR "SRP reset_device called\n");
1216
1217         return srp_send_tsk_mgmt(scmnd, SRP_TSK_LUN_RESET);
1218 }
1219
1220 static int srp_reset_host(struct scsi_cmnd *scmnd)
1221 {
1222         struct srp_target_port *target = host_to_target(scmnd->device->host);
1223         int ret = FAILED;
1224
1225         printk(KERN_ERR PFX "SRP reset_host called\n");
1226
1227         if (!srp_reconnect_target(target))
1228                 ret = SUCCESS;
1229
1230         return ret;
1231 }
1232
1233 static ssize_t show_id_ext(struct class_device *cdev, char *buf)
1234 {
1235         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1236
1237         if (target->state == SRP_TARGET_DEAD ||
1238             target->state == SRP_TARGET_REMOVED)
1239                 return -ENODEV;
1240
1241         return sprintf(buf, "0x%016llx\n",
1242                        (unsigned long long) be64_to_cpu(target->id_ext));
1243 }
1244
1245 static ssize_t show_ioc_guid(struct class_device *cdev, char *buf)
1246 {
1247         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1248
1249         if (target->state == SRP_TARGET_DEAD ||
1250             target->state == SRP_TARGET_REMOVED)
1251                 return -ENODEV;
1252
1253         return sprintf(buf, "0x%016llx\n",
1254                        (unsigned long long) be64_to_cpu(target->ioc_guid));
1255 }
1256
1257 static ssize_t show_service_id(struct class_device *cdev, char *buf)
1258 {
1259         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1260
1261         if (target->state == SRP_TARGET_DEAD ||
1262             target->state == SRP_TARGET_REMOVED)
1263                 return -ENODEV;
1264
1265         return sprintf(buf, "0x%016llx\n",
1266                        (unsigned long long) be64_to_cpu(target->service_id));
1267 }
1268
1269 static ssize_t show_pkey(struct class_device *cdev, char *buf)
1270 {
1271         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1272
1273         if (target->state == SRP_TARGET_DEAD ||
1274             target->state == SRP_TARGET_REMOVED)
1275                 return -ENODEV;
1276
1277         return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1278 }
1279
1280 static ssize_t show_dgid(struct class_device *cdev, char *buf)
1281 {
1282         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1283
1284         if (target->state == SRP_TARGET_DEAD ||
1285             target->state == SRP_TARGET_REMOVED)
1286                 return -ENODEV;
1287
1288         return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1289                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
1290                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
1291                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
1292                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
1293                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
1294                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
1295                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
1296                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
1297 }
1298
1299 static CLASS_DEVICE_ATTR(id_ext,        S_IRUGO, show_id_ext,           NULL);
1300 static CLASS_DEVICE_ATTR(ioc_guid,      S_IRUGO, show_ioc_guid,         NULL);
1301 static CLASS_DEVICE_ATTR(service_id,    S_IRUGO, show_service_id,       NULL);
1302 static CLASS_DEVICE_ATTR(pkey,          S_IRUGO, show_pkey,             NULL);
1303 static CLASS_DEVICE_ATTR(dgid,          S_IRUGO, show_dgid,             NULL);
1304
1305 static struct class_device_attribute *srp_host_attrs[] = {
1306         &class_device_attr_id_ext,
1307         &class_device_attr_ioc_guid,
1308         &class_device_attr_service_id,
1309         &class_device_attr_pkey,
1310         &class_device_attr_dgid,
1311         NULL
1312 };
1313
1314 static struct scsi_host_template srp_template = {
1315         .module                         = THIS_MODULE,
1316         .name                           = DRV_NAME,
1317         .info                           = srp_target_info,
1318         .queuecommand                   = srp_queuecommand,
1319         .eh_abort_handler               = srp_abort,
1320         .eh_device_reset_handler        = srp_reset_device,
1321         .eh_host_reset_handler          = srp_reset_host,
1322         .can_queue                      = SRP_SQ_SIZE,
1323         .this_id                        = -1,
1324         .sg_tablesize                   = SRP_MAX_INDIRECT,
1325         .cmd_per_lun                    = SRP_SQ_SIZE,
1326         .use_clustering                 = ENABLE_CLUSTERING,
1327         .shost_attrs                    = srp_host_attrs
1328 };
1329
1330 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1331 {
1332         sprintf(target->target_name, "SRP.T10:%016llX",
1333                  (unsigned long long) be64_to_cpu(target->id_ext));
1334
1335         if (scsi_add_host(target->scsi_host, host->dev->dma_device))
1336                 return -ENODEV;
1337
1338         mutex_lock(&host->target_mutex);
1339         list_add_tail(&target->list, &host->target_list);
1340         mutex_unlock(&host->target_mutex);
1341
1342         target->state = SRP_TARGET_LIVE;
1343
1344         /* XXX: are we supposed to have a definition of SCAN_WILD_CARD ?? */
1345         scsi_scan_target(&target->scsi_host->shost_gendev,
1346                          0, target->scsi_id, ~0, 0);
1347
1348         return 0;
1349 }
1350
1351 static void srp_release_class_dev(struct class_device *class_dev)
1352 {
1353         struct srp_host *host =
1354                 container_of(class_dev, struct srp_host, class_dev);
1355
1356         complete(&host->released);
1357 }
1358
1359 static struct class srp_class = {
1360         .name    = "infiniband_srp",
1361         .release = srp_release_class_dev
1362 };
1363
1364 /*
1365  * Target ports are added by writing
1366  *
1367  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1368  *     pkey=<P_Key>,service_id=<service ID>
1369  *
1370  * to the add_target sysfs attribute.
1371  */
1372 enum {
1373         SRP_OPT_ERR             = 0,
1374         SRP_OPT_ID_EXT          = 1 << 0,
1375         SRP_OPT_IOC_GUID        = 1 << 1,
1376         SRP_OPT_DGID            = 1 << 2,
1377         SRP_OPT_PKEY            = 1 << 3,
1378         SRP_OPT_SERVICE_ID      = 1 << 4,
1379         SRP_OPT_MAX_SECT        = 1 << 5,
1380         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1381                                    SRP_OPT_IOC_GUID     |
1382                                    SRP_OPT_DGID         |
1383                                    SRP_OPT_PKEY         |
1384                                    SRP_OPT_SERVICE_ID),
1385 };
1386
1387 static match_table_t srp_opt_tokens = {
1388         { SRP_OPT_ID_EXT,       "id_ext=%s"     },
1389         { SRP_OPT_IOC_GUID,     "ioc_guid=%s"   },
1390         { SRP_OPT_DGID,         "dgid=%s"       },
1391         { SRP_OPT_PKEY,         "pkey=%x"       },
1392         { SRP_OPT_SERVICE_ID,   "service_id=%s" },
1393         { SRP_OPT_MAX_SECT,     "max_sect=%d"   },
1394         { SRP_OPT_ERR,          NULL            }
1395 };
1396
1397 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1398 {
1399         char *options, *sep_opt;
1400         char *p;
1401         char dgid[3];
1402         substring_t args[MAX_OPT_ARGS];
1403         int opt_mask = 0;
1404         int token;
1405         int ret = -EINVAL;
1406         int i;
1407
1408         options = kstrdup(buf, GFP_KERNEL);
1409         if (!options)
1410                 return -ENOMEM;
1411
1412         sep_opt = options;
1413         while ((p = strsep(&sep_opt, ",")) != NULL) {
1414                 if (!*p)
1415                         continue;
1416
1417                 token = match_token(p, srp_opt_tokens, args);
1418                 opt_mask |= token;
1419
1420                 switch (token) {
1421                 case SRP_OPT_ID_EXT:
1422                         p = match_strdup(args);
1423                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1424                         kfree(p);
1425                         break;
1426
1427                 case SRP_OPT_IOC_GUID:
1428                         p = match_strdup(args);
1429                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1430                         kfree(p);
1431                         break;
1432
1433                 case SRP_OPT_DGID:
1434                         p = match_strdup(args);
1435                         if (strlen(p) != 32) {
1436                                 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1437                                 goto out;
1438                         }
1439
1440                         for (i = 0; i < 16; ++i) {
1441                                 strlcpy(dgid, p + i * 2, 3);
1442                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1443                         }
1444                         kfree(p);
1445                         break;
1446
1447                 case SRP_OPT_PKEY:
1448                         if (match_hex(args, &token)) {
1449                                 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1450                                 goto out;
1451                         }
1452                         target->path.pkey = cpu_to_be16(token);
1453                         break;
1454
1455                 case SRP_OPT_SERVICE_ID:
1456                         p = match_strdup(args);
1457                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1458                         kfree(p);
1459                         break;
1460
1461                 case SRP_OPT_MAX_SECT:
1462                         if (match_int(args, &token)) {
1463                                 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1464                                 goto out;
1465                         }
1466                         target->scsi_host->max_sectors = token;
1467                         break;
1468
1469                 default:
1470                         printk(KERN_WARNING PFX "unknown parameter or missing value "
1471                                "'%s' in target creation request\n", p);
1472                         goto out;
1473                 }
1474         }
1475
1476         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1477                 ret = 0;
1478         else
1479                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1480                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1481                             !(srp_opt_tokens[i].token & opt_mask))
1482                                 printk(KERN_WARNING PFX "target creation request is "
1483                                        "missing parameter '%s'\n",
1484                                        srp_opt_tokens[i].pattern);
1485
1486 out:
1487         kfree(options);
1488         return ret;
1489 }
1490
1491 static ssize_t srp_create_target(struct class_device *class_dev,
1492                                  const char *buf, size_t count)
1493 {
1494         struct srp_host *host =
1495                 container_of(class_dev, struct srp_host, class_dev);
1496         struct Scsi_Host *target_host;
1497         struct srp_target_port *target;
1498         int ret;
1499         int i;
1500
1501         target_host = scsi_host_alloc(&srp_template,
1502                                       sizeof (struct srp_target_port));
1503         if (!target_host)
1504                 return -ENOMEM;
1505
1506         target_host->max_lun = SRP_MAX_LUN;
1507
1508         target = host_to_target(target_host);
1509         memset(target, 0, sizeof *target);
1510
1511         target->scsi_host  = target_host;
1512         target->srp_host   = host;
1513
1514         INIT_WORK(&target->work, srp_reconnect_work, target);
1515
1516         for (i = 0; i < SRP_SQ_SIZE - 1; ++i)
1517                 target->req_ring[i].next = i + 1;
1518         target->req_ring[SRP_SQ_SIZE - 1].next = -1;
1519         INIT_LIST_HEAD(&target->req_queue);
1520
1521         ret = srp_parse_options(buf, target);
1522         if (ret)
1523                 goto err;
1524
1525         ib_get_cached_gid(host->dev, host->port, 0, &target->path.sgid);
1526
1527         printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1528                "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1529                (unsigned long long) be64_to_cpu(target->id_ext),
1530                (unsigned long long) be64_to_cpu(target->ioc_guid),
1531                be16_to_cpu(target->path.pkey),
1532                (unsigned long long) be64_to_cpu(target->service_id),
1533                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
1534                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
1535                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
1536                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
1537                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
1538                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
1539                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
1540                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
1541
1542         ret = srp_create_target_ib(target);
1543         if (ret)
1544                 goto err;
1545
1546         target->cm_id = ib_create_cm_id(host->dev, srp_cm_handler, target);
1547         if (IS_ERR(target->cm_id)) {
1548                 ret = PTR_ERR(target->cm_id);
1549                 goto err_free;
1550         }
1551
1552         ret = srp_connect_target(target);
1553         if (ret) {
1554                 printk(KERN_ERR PFX "Connection failed\n");
1555                 goto err_cm_id;
1556         }
1557
1558         ret = srp_add_target(host, target);
1559         if (ret)
1560                 goto err_disconnect;
1561
1562         return count;
1563
1564 err_disconnect:
1565         srp_disconnect_target(target);
1566
1567 err_cm_id:
1568         ib_destroy_cm_id(target->cm_id);
1569
1570 err_free:
1571         srp_free_target_ib(target);
1572
1573 err:
1574         scsi_host_put(target_host);
1575
1576         return ret;
1577 }
1578
1579 static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1580
1581 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
1582 {
1583         struct srp_host *host =
1584                 container_of(class_dev, struct srp_host, class_dev);
1585
1586         return sprintf(buf, "%s\n", host->dev->name);
1587 }
1588
1589 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1590
1591 static ssize_t show_port(struct class_device *class_dev, char *buf)
1592 {
1593         struct srp_host *host =
1594                 container_of(class_dev, struct srp_host, class_dev);
1595
1596         return sprintf(buf, "%d\n", host->port);
1597 }
1598
1599 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1600
1601 static struct srp_host *srp_add_port(struct ib_device *device, u8 port)
1602 {
1603         struct srp_host *host;
1604
1605         host = kzalloc(sizeof *host, GFP_KERNEL);
1606         if (!host)
1607                 return NULL;
1608
1609         INIT_LIST_HEAD(&host->target_list);
1610         mutex_init(&host->target_mutex);
1611         init_completion(&host->released);
1612         host->dev  = device;
1613         host->port = port;
1614
1615         host->initiator_port_id[7] = port;
1616         memcpy(host->initiator_port_id + 8, &device->node_guid, 8);
1617
1618         host->pd   = ib_alloc_pd(device);
1619         if (IS_ERR(host->pd))
1620                 goto err_free;
1621
1622         host->mr   = ib_get_dma_mr(host->pd,
1623                                    IB_ACCESS_LOCAL_WRITE |
1624                                    IB_ACCESS_REMOTE_READ |
1625                                    IB_ACCESS_REMOTE_WRITE);
1626         if (IS_ERR(host->mr))
1627                 goto err_pd;
1628
1629         host->class_dev.class = &srp_class;
1630         host->class_dev.dev   = device->dma_device;
1631         snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
1632                  device->name, port);
1633
1634         if (class_device_register(&host->class_dev))
1635                 goto err_mr;
1636         if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
1637                 goto err_class;
1638         if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
1639                 goto err_class;
1640         if (class_device_create_file(&host->class_dev, &class_device_attr_port))
1641                 goto err_class;
1642
1643         return host;
1644
1645 err_class:
1646         class_device_unregister(&host->class_dev);
1647
1648 err_mr:
1649         ib_dereg_mr(host->mr);
1650
1651 err_pd:
1652         ib_dealloc_pd(host->pd);
1653
1654 err_free:
1655         kfree(host);
1656
1657         return NULL;
1658 }
1659
1660 static void srp_add_one(struct ib_device *device)
1661 {
1662         struct list_head *dev_list;
1663         struct srp_host *host;
1664         int s, e, p;
1665
1666         dev_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
1667         if (!dev_list)
1668                 return;
1669
1670         INIT_LIST_HEAD(dev_list);
1671
1672         if (device->node_type == IB_NODE_SWITCH) {
1673                 s = 0;
1674                 e = 0;
1675         } else {
1676                 s = 1;
1677                 e = device->phys_port_cnt;
1678         }
1679
1680         for (p = s; p <= e; ++p) {
1681                 host = srp_add_port(device, p);
1682                 if (host)
1683                         list_add_tail(&host->list, dev_list);
1684         }
1685
1686         ib_set_client_data(device, &srp_client, dev_list);
1687 }
1688
1689 static void srp_remove_one(struct ib_device *device)
1690 {
1691         struct list_head *dev_list;
1692         struct srp_host *host, *tmp_host;
1693         LIST_HEAD(target_list);
1694         struct srp_target_port *target, *tmp_target;
1695         unsigned long flags;
1696
1697         dev_list = ib_get_client_data(device, &srp_client);
1698
1699         list_for_each_entry_safe(host, tmp_host, dev_list, list) {
1700                 class_device_unregister(&host->class_dev);
1701                 /*
1702                  * Wait for the sysfs entry to go away, so that no new
1703                  * target ports can be created.
1704                  */
1705                 wait_for_completion(&host->released);
1706
1707                 /*
1708                  * Mark all target ports as removed, so we stop queueing
1709                  * commands and don't try to reconnect.
1710                  */
1711                 mutex_lock(&host->target_mutex);
1712                 list_for_each_entry_safe(target, tmp_target,
1713                                          &host->target_list, list) {
1714                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
1715                         if (target->state != SRP_TARGET_REMOVED)
1716                                 target->state = SRP_TARGET_REMOVED;
1717                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
1718                 }
1719                 mutex_unlock(&host->target_mutex);
1720
1721                 /*
1722                  * Wait for any reconnection tasks that may have
1723                  * started before we marked our target ports as
1724                  * removed, and any target port removal tasks.
1725                  */
1726                 flush_scheduled_work();
1727
1728                 list_for_each_entry_safe(target, tmp_target,
1729                                          &host->target_list, list) {
1730                         scsi_remove_host(target->scsi_host);
1731                         srp_disconnect_target(target);
1732                         ib_destroy_cm_id(target->cm_id);
1733                         srp_free_target_ib(target);
1734                         scsi_host_put(target->scsi_host);
1735                 }
1736
1737                 ib_dereg_mr(host->mr);
1738                 ib_dealloc_pd(host->pd);
1739                 kfree(host);
1740         }
1741
1742         kfree(dev_list);
1743 }
1744
1745 static int __init srp_init_module(void)
1746 {
1747         int ret;
1748
1749         ret = class_register(&srp_class);
1750         if (ret) {
1751                 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
1752                 return ret;
1753         }
1754
1755         ret = ib_register_client(&srp_client);
1756         if (ret) {
1757                 printk(KERN_ERR PFX "couldn't register IB client\n");
1758                 class_unregister(&srp_class);
1759                 return ret;
1760         }
1761
1762         return 0;
1763 }
1764
1765 static void __exit srp_cleanup_module(void)
1766 {
1767         ib_unregister_client(&srp_client);
1768         class_unregister(&srp_class);
1769 }
1770
1771 module_init(srp_init_module);
1772 module_exit(srp_cleanup_module);