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         if (ib_send_cm_dreq(target->cm_id, NULL, 0)) {
 344                 printk(KERN_DEBUG PFX "Sending CM DREQ failed\n");
 345                 return;
 346         }
 347         wait_for_completion(&target->done);
 348 }
 349
 350 static void srp_remove_work(void *target_ptr)
 351 {
 352         struct srp_target_port *target = target_ptr;
 353
 354         spin_lock_irq(target->scsi_host->host_lock);
 355         if (target->state != SRP_TARGET_DEAD) {
 356                 spin_unlock_irq(target->scsi_host->host_lock);
 357                 scsi_host_put(target->scsi_host);
 358                 return;
 359         }
 360         target->state = SRP_TARGET_REMOVED;
 361         spin_unlock_irq(target->scsi_host->host_lock);
 362
 363         mutex_lock(&target->srp_host->target_mutex);
 364         list_del(&target->list);
 365         mutex_unlock(&target->srp_host->target_mutex);
 366
 367         scsi_remove_host(target->scsi_host);
 368         ib_destroy_cm_id(target->cm_id);
 369         srp_free_target_ib(target);
 370         scsi_host_put(target->scsi_host);
 371         /* And another put to really free the target port... */
 372         scsi_host_put(target->scsi_host);
 373 }
 374
 375 static int srp_connect_target(struct srp_target_port *target)
 376 {
 377         int ret;
 378
 379         ret = srp_lookup_path(target);
 380         if (ret)
 381                 return ret;
 382
 383         while (1) {
 384                 init_completion(&target->done);
 385                 ret = srp_send_req(target);
 386                 if (ret)
 387                         return ret;
 388                 wait_for_completion(&target->done);
 389
 390                 /*
 391                  * The CM event handling code will set status to
 392                  * SRP_PORT_REDIRECT if we get a port redirect REJ
 393                  * back, or SRP_DLID_REDIRECT if we get a lid/qp
 394                  * redirect REJ back.
 395                  */
 396                 switch (target->status) {
 397                 case 0:
 398                         return 0;
 399
 400                 case SRP_PORT_REDIRECT:
 401                         ret = srp_lookup_path(target);
 402                         if (ret)
 403                                 return ret;
 404                         break;
 405
 406                 case SRP_DLID_REDIRECT:
 407                         break;
 408
 409                 default:
 410                         return target->status;
 411                 }
 412         }
 413 }
 414
 415 static void srp_unmap_data(struct scsi_cmnd *scmnd,
 416                            struct srp_target_port *target,
 417                            struct srp_request *req)
 418 {
 419         struct scatterlist *scat;
 420         int nents;
 421
 422         if (!scmnd->request_buffer ||
 423             (scmnd->sc_data_direction != DMA_TO_DEVICE &&
 424              scmnd->sc_data_direction != DMA_FROM_DEVICE))
 425                 return;
 426
 427         /*
 428          * This handling of non-SG commands can be killed when the
 429          * SCSI midlayer no longer generates non-SG commands.
 430          */
 431         if (likely(scmnd->use_sg)) {
 432                 nents = scmnd->use_sg;
 433                 scat  = scmnd->request_buffer;
 434         } else {
 435                 nents = 1;
 436                 scat  = &req->fake_sg;
 437         }
 438
 439         dma_unmap_sg(target->srp_host->dev->dma_device, scat, nents,
 440                      scmnd->sc_data_direction);
 441 }
 442
 443 static int srp_reconnect_target(struct srp_target_port *target)
 444 {
 445         struct ib_cm_id *new_cm_id;
 446         struct ib_qp_attr qp_attr;
 447         struct srp_request *req;
 448         struct ib_wc wc;
 449         int ret;
 450         int i;
 451
 452         spin_lock_irq(target->scsi_host->host_lock);
 453         if (target->state != SRP_TARGET_LIVE) {
 454                 spin_unlock_irq(target->scsi_host->host_lock);
 455                 return -EAGAIN;
 456         }
 457         target->state = SRP_TARGET_CONNECTING;
 458         spin_unlock_irq(target->scsi_host->host_lock);
 459
 460         srp_disconnect_target(target);
 461         /*
 462          * Now get a new local CM ID so that we avoid confusing the
 463          * target in case things are really fouled up.
 464          */
 465         new_cm_id = ib_create_cm_id(target->srp_host->dev,
 466                                     srp_cm_handler, target);
 467         if (IS_ERR(new_cm_id)) {
 468                 ret = PTR_ERR(new_cm_id);
 469                 goto err;
 470         }
 471         ib_destroy_cm_id(target->cm_id);
 472         target->cm_id = new_cm_id;
 473
 474         qp_attr.qp_state = IB_QPS_RESET;
 475         ret = ib_modify_qp(target->qp, &qp_attr, IB_QP_STATE);
 476         if (ret)
 477                 goto err;
 478
 479         ret = srp_init_qp(target, target->qp);
 480         if (ret)
 481                 goto err;
 482
 483         while (ib_poll_cq(target->cq, 1, &wc) > 0)
 484                 ; /* nothing */
 485
 486         list_for_each_entry(req, &target->req_queue, list) {
 487                 req->scmnd->result = DID_RESET << 16;
 488                 req->scmnd->scsi_done(req->scmnd);
 489                 srp_unmap_data(req->scmnd, target, req);
 490         }
 491
 492         target->rx_head  = 0;
 493         target->tx_head  = 0;
 494         target->tx_tail  = 0;
 495         INIT_LIST_HEAD(&target->free_reqs);
 496         INIT_LIST_HEAD(&target->req_queue);
 497         for (i = 0; i < SRP_SQ_SIZE; ++i)
 498                 list_add_tail(&target->req_ring[i].list, &target->free_reqs);
 499
 500         ret = srp_connect_target(target);
 501         if (ret)
 502                 goto err;
 503
 504         spin_lock_irq(target->scsi_host->host_lock);
 505         if (target->state == SRP_TARGET_CONNECTING) {
 506                 ret = 0;
 507                 target->state = SRP_TARGET_LIVE;
 508         } else
 509                 ret = -EAGAIN;
 510         spin_unlock_irq(target->scsi_host->host_lock);
 511
 512         return ret;
 513
 514 err:
 515         printk(KERN_ERR PFX "reconnect failed (%d), removing target port.\n", ret);
 516
 517         /*
 518          * We couldn't reconnect, so kill our target port off.
 519          * However, we have to defer the real removal because we might
 520          * be in the context of the SCSI error handler now, which
 521          * would deadlock if we call scsi_remove_host().
 522          */
 523         spin_lock_irq(target->scsi_host->host_lock);
 524         if (target->state == SRP_TARGET_CONNECTING) {
 525                 target->state = SRP_TARGET_DEAD;
 526                 INIT_WORK(&target->work, srp_remove_work, target);
 527                 schedule_work(&target->work);
 528         }
 529         spin_unlock_irq(target->scsi_host->host_lock);
 530
 531         return ret;
 532 }
 533
 534 static int srp_map_data(struct scsi_cmnd *scmnd, struct srp_target_port *target,
 535                         struct srp_request *req)
 536 {
 537         struct scatterlist *scat;
 538         struct srp_cmd *cmd = req->cmd->buf;
 539         int len, nents, count;
 540         int i;
 541         u8 fmt;
 542
 543         if (!scmnd->request_buffer || scmnd->sc_data_direction == DMA_NONE)
 544                 return sizeof (struct srp_cmd);
 545
 546         if (scmnd->sc_data_direction != DMA_FROM_DEVICE &&
 547             scmnd->sc_data_direction != DMA_TO_DEVICE) {
 548                 printk(KERN_WARNING PFX "Unhandled data direction %d\n",
 549                        scmnd->sc_data_direction);
 550                 return -EINVAL;
 551         }
 552
 553         /*
 554          * This handling of non-SG commands can be killed when the
 555          * SCSI midlayer no longer generates non-SG commands.
 556          */
 557         if (likely(scmnd->use_sg)) {
 558                 nents = scmnd->use_sg;
 559                 scat  = scmnd->request_buffer;
 560         } else {
 561                 nents = 1;
 562                 scat  = &req->fake_sg;
 563                 sg_init_one(scat, scmnd->request_buffer, scmnd->request_bufflen);
 564         }
 565
 566         count = dma_map_sg(target->srp_host->dev->dma_device, scat, nents,
 567                            scmnd->sc_data_direction);
 568
 569         if (count == 1) {
 570                 struct srp_direct_buf *buf = (void *) cmd->add_data;
 571
 572                 fmt = SRP_DATA_DESC_DIRECT;
 573
 574                 buf->va  = cpu_to_be64(sg_dma_address(scat));
 575                 buf->key = cpu_to_be32(target->srp_host->mr->rkey);
 576                 buf->len = cpu_to_be32(sg_dma_len(scat));
 577
 578                 len = sizeof (struct srp_cmd) +
 579                         sizeof (struct srp_direct_buf);
 580         } else {
 581                 struct srp_indirect_buf *buf = (void *) cmd->add_data;
 582                 u32 datalen = 0;
 583
 584                 fmt = SRP_DATA_DESC_INDIRECT;
 585
 586                 if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 587                         cmd->data_out_desc_cnt = count;
 588                 else
 589                         cmd->data_in_desc_cnt = count;
 590
 591                 buf->table_desc.va  = cpu_to_be64(req->cmd->dma +
 592                                                   sizeof *cmd +
 593                                                   sizeof *buf);
 594                 buf->table_desc.key =
 595                         cpu_to_be32(target->srp_host->mr->rkey);
 596                 buf->table_desc.len =
 597                         cpu_to_be32(count * sizeof (struct srp_direct_buf));
 598
 599                 for (i = 0; i < count; ++i) {
 600                         buf->desc_list[i].va  = cpu_to_be64(sg_dma_address(&scat[i]));
 601                         buf->desc_list[i].key =
 602                                 cpu_to_be32(target->srp_host->mr->rkey);
 603                         buf->desc_list[i].len = cpu_to_be32(sg_dma_len(&scat[i]));
 604
 605                         datalen += sg_dma_len(&scat[i]);
 606                 }
 607
 608                 buf->len = cpu_to_be32(datalen);
 609
 610                 len = sizeof (struct srp_cmd) +
 611                         sizeof (struct srp_indirect_buf) +
 612                         count * sizeof (struct srp_direct_buf);
 613         }
 614
 615         if (scmnd->sc_data_direction == DMA_TO_DEVICE)
 616                 cmd->buf_fmt = fmt << 4;
 617         else
 618                 cmd->buf_fmt = fmt;
 619
 620         return len;
 621 }
 622
 623 static void srp_remove_req(struct srp_target_port *target, struct srp_request *req)
 624 {
 625         srp_unmap_data(req->scmnd, target, req);
 626         list_move_tail(&req->list, &target->free_reqs);
 627 }
 628
 629 static void srp_process_rsp(struct srp_target_port *target, struct srp_rsp *rsp)
 630 {
 631         struct srp_request *req;
 632         struct scsi_cmnd *scmnd;
 633         unsigned long flags;
 634         s32 delta;
 635
 636         delta = (s32) be32_to_cpu(rsp->req_lim_delta);
 637
 638         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 639
 640         target->req_lim += delta;
 641
 642         req = &target->req_ring[rsp->tag & ~SRP_TAG_TSK_MGMT];
 643
 644         if (unlikely(rsp->tag & SRP_TAG_TSK_MGMT)) {
 645                 if (be32_to_cpu(rsp->resp_data_len) < 4)
 646                         req->tsk_status = -1;
 647                 else
 648                         req->tsk_status = rsp->data[3];
 649                 complete(&req->done);
 650         } else {
 651                 scmnd = req->scmnd;
 652                 if (!scmnd)
 653                         printk(KERN_ERR "Null scmnd for RSP w/tag %016llx\n",
 654                                (unsigned long long) rsp->tag);
 655                 scmnd->result = rsp->status;
 656
 657                 if (rsp->flags & SRP_RSP_FLAG_SNSVALID) {
 658                         memcpy(scmnd->sense_buffer, rsp->data +
 659                                be32_to_cpu(rsp->resp_data_len),
 660                                min_t(int, be32_to_cpu(rsp->sense_data_len),
 661                                      SCSI_SENSE_BUFFERSIZE));
 662                 }
 663
 664                 if (rsp->flags & (SRP_RSP_FLAG_DOOVER | SRP_RSP_FLAG_DOUNDER))
 665                         scmnd->resid = be32_to_cpu(rsp->data_out_res_cnt);
 666                 else if (rsp->flags & (SRP_RSP_FLAG_DIOVER | SRP_RSP_FLAG_DIUNDER))
 667                         scmnd->resid = be32_to_cpu(rsp->data_in_res_cnt);
 668
 669                 if (!req->tsk_mgmt) {
 670                         scmnd->host_scribble = (void *) -1L;
 671                         scmnd->scsi_done(scmnd);
 672
 673                         srp_remove_req(target, req);
 674                 } else
 675                         req->cmd_done = 1;
 676         }
 677
 678         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 679 }
 680
 681 static void srp_reconnect_work(void *target_ptr)
 682 {
 683         struct srp_target_port *target = target_ptr;
 684
 685         srp_reconnect_target(target);
 686 }
 687
 688 static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
 689 {
 690         struct srp_iu *iu;
 691         u8 opcode;
 692
 693         iu = target->rx_ring[wc->wr_id & ~SRP_OP_RECV];
 694
 695         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 696                                 target->max_ti_iu_len, DMA_FROM_DEVICE);
 697
 698         opcode = *(u8 *) iu->buf;
 699
 700         if (0) {
 701                 int i;
 702
 703                 printk(KERN_ERR PFX "recv completion, opcode 0x%02x\n", opcode);
 704
 705                 for (i = 0; i < wc->byte_len; ++i) {
 706                         if (i % 8 == 0)
 707                                 printk(KERN_ERR "  [%02x] ", i);
 708                         printk(" %02x", ((u8 *) iu->buf)[i]);
 709                         if ((i + 1) % 8 == 0)
 710                                 printk("\n");
 711                 }
 712
 713                 if (wc->byte_len % 8)
 714                         printk("\n");
 715         }
 716
 717         switch (opcode) {
 718         case SRP_RSP:
 719                 srp_process_rsp(target, iu->buf);
 720                 break;
 721
 722         case SRP_T_LOGOUT:
 723                 /* XXX Handle target logout */
 724                 printk(KERN_WARNING PFX "Got target logout request\n");
 725                 break;
 726
 727         default:
 728                 printk(KERN_WARNING PFX "Unhandled SRP opcode 0x%02x\n", opcode);
 729                 break;
 730         }
 731
 732         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 733                                    target->max_ti_iu_len, DMA_FROM_DEVICE);
 734 }
 735
 736 static void srp_completion(struct ib_cq *cq, void *target_ptr)
 737 {
 738         struct srp_target_port *target = target_ptr;
 739         struct ib_wc wc;
 740         unsigned long flags;
 741
 742         ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
 743         while (ib_poll_cq(cq, 1, &wc) > 0) {
 744                 if (wc.status) {
 745                         printk(KERN_ERR PFX "failed %s status %d\n",
 746                                wc.wr_id & SRP_OP_RECV ? "receive" : "send",
 747                                wc.status);
 748                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 749                         if (target->state == SRP_TARGET_LIVE)
 750                                 schedule_work(&target->work);
 751                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 752                         break;
 753                 }
 754
 755                 if (wc.wr_id & SRP_OP_RECV)
 756                         srp_handle_recv(target, &wc);
 757                 else
 758                         ++target->tx_tail;
 759         }
 760 }
 761
 762 static int __srp_post_recv(struct srp_target_port *target)
 763 {
 764         struct srp_iu *iu;
 765         struct ib_sge list;
 766         struct ib_recv_wr wr, *bad_wr;
 767         unsigned int next;
 768         int ret;
 769
 770         next     = target->rx_head & (SRP_RQ_SIZE - 1);
 771         wr.wr_id = next | SRP_OP_RECV;
 772         iu       = target->rx_ring[next];
 773
 774         list.addr   = iu->dma;
 775         list.length = iu->size;
 776         list.lkey   = target->srp_host->mr->lkey;
 777
 778         wr.next     = NULL;
 779         wr.sg_list  = &list;
 780         wr.num_sge  = 1;
 781
 782         ret = ib_post_recv(target->qp, &wr, &bad_wr);
 783         if (!ret)
 784                 ++target->rx_head;
 785
 786         return ret;
 787 }
 788
 789 static int srp_post_recv(struct srp_target_port *target)
 790 {
 791         unsigned long flags;
 792         int ret;
 793
 794         spin_lock_irqsave(target->scsi_host->host_lock, flags);
 795         ret = __srp_post_recv(target);
 796         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
 797
 798         return ret;
 799 }
 800
 801 /*
 802  * Must be called with target->scsi_host->host_lock held to protect
 803  * req_lim and tx_head.  Lock cannot be dropped between call here and
 804  * call to __srp_post_send().
 805  */
 806 static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target)
 807 {
 808         if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
 809                 return NULL;
 810
 811         if (unlikely(target->req_lim < 1)) {
 812                 if (printk_ratelimit())
 813                         printk(KERN_DEBUG PFX "Target has req_lim %d\n",
 814                                target->req_lim);
 815                 return NULL;
 816         }
 817
 818         return target->tx_ring[target->tx_head & SRP_SQ_SIZE];
 819 }
 820
 821 /*
 822  * Must be called with target->scsi_host->host_lock held to protect
 823  * req_lim and tx_head.
 824  */
 825 static int __srp_post_send(struct srp_target_port *target,
 826                            struct srp_iu *iu, int len)
 827 {
 828         struct ib_sge list;
 829         struct ib_send_wr wr, *bad_wr;
 830         int ret = 0;
 831
 832         list.addr   = iu->dma;
 833         list.length = len;
 834         list.lkey   = target->srp_host->mr->lkey;
 835
 836         wr.next       = NULL;
 837         wr.wr_id      = target->tx_head & SRP_SQ_SIZE;
 838         wr.sg_list    = &list;
 839         wr.num_sge    = 1;
 840         wr.opcode     = IB_WR_SEND;
 841         wr.send_flags = IB_SEND_SIGNALED;
 842
 843         ret = ib_post_send(target->qp, &wr, &bad_wr);
 844
 845         if (!ret) {
 846                 ++target->tx_head;
 847                 --target->req_lim;
 848         }
 849
 850         return ret;
 851 }
 852
 853 static int srp_queuecommand(struct scsi_cmnd *scmnd,
 854                             void (*done)(struct scsi_cmnd *))
 855 {
 856         struct srp_target_port *target = host_to_target(scmnd->device->host);
 857         struct srp_request *req;
 858         struct srp_iu *iu;
 859         struct srp_cmd *cmd;
 860         int len;
 861
 862         if (target->state == SRP_TARGET_CONNECTING)
 863                 goto err;
 864
 865         if (target->state == SRP_TARGET_DEAD ||
 866             target->state == SRP_TARGET_REMOVED) {
 867                 scmnd->result = DID_BAD_TARGET << 16;
 868                 done(scmnd);
 869                 return 0;
 870         }
 871
 872         iu = __srp_get_tx_iu(target);
 873         if (!iu)
 874                 goto err;
 875
 876         dma_sync_single_for_cpu(target->srp_host->dev->dma_device, iu->dma,
 877                                 SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 878
 879         req = list_entry(target->free_reqs.next, struct srp_request, list);
 880
 881         scmnd->scsi_done     = done;
 882         scmnd->result        = 0;
 883         scmnd->host_scribble = (void *) (long) req->index;
 884
 885         cmd = iu->buf;
 886         memset(cmd, 0, sizeof *cmd);
 887
 888         cmd->opcode = SRP_CMD;
 889         cmd->lun    = cpu_to_be64((u64) scmnd->device->lun << 48);
 890         cmd->tag    = req->index;
 891         memcpy(cmd->cdb, scmnd->cmnd, scmnd->cmd_len);
 892
 893         req->scmnd    = scmnd;
 894         req->cmd      = iu;
 895         req->cmd_done = 0;
 896         req->tsk_mgmt = NULL;
 897
 898         len = srp_map_data(scmnd, target, req);
 899         if (len < 0) {
 900                 printk(KERN_ERR PFX "Failed to map data\n");
 901                 goto err;
 902         }
 903
 904         if (__srp_post_recv(target)) {
 905                 printk(KERN_ERR PFX "Recv failed\n");
 906                 goto err_unmap;
 907         }
 908
 909         dma_sync_single_for_device(target->srp_host->dev->dma_device, iu->dma,
 910                                    SRP_MAX_IU_LEN, DMA_TO_DEVICE);
 911
 912         if (__srp_post_send(target, iu, len)) {
 913                 printk(KERN_ERR PFX "Send failed\n");
 914                 goto err_unmap;
 915         }
 916
 917         list_move_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 srp_target_port *target,
1141                              struct srp_request *req, u8 func)
1142 {
1143         struct srp_iu *iu;
1144         struct srp_tsk_mgmt *tsk_mgmt;
1145
1146         spin_lock_irq(target->scsi_host->host_lock);
1147
1148         if (target->state == SRP_TARGET_DEAD ||
1149             target->state == SRP_TARGET_REMOVED) {
1150                 req->scmnd->result = DID_BAD_TARGET << 16;
1151                 goto out;
1152         }
1153
1154         init_completion(&req->done);
1155
1156         iu = __srp_get_tx_iu(target);
1157         if (!iu)
1158                 goto out;
1159
1160         tsk_mgmt = iu->buf;
1161         memset(tsk_mgmt, 0, sizeof *tsk_mgmt);
1162
1163         tsk_mgmt->opcode        = SRP_TSK_MGMT;
1164         tsk_mgmt->lun           = cpu_to_be64((u64) req->scmnd->device->lun << 48);
1165         tsk_mgmt->tag           = req->index | SRP_TAG_TSK_MGMT;
1166         tsk_mgmt->tsk_mgmt_func = func;
1167         tsk_mgmt->task_tag      = req->index;
1168
1169         if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
1170                 goto out;
1171
1172         req->tsk_mgmt = iu;
1173
1174         spin_unlock_irq(target->scsi_host->host_lock);
1175
1176         if (!wait_for_completion_timeout(&req->done,
1177                                          msecs_to_jiffies(SRP_ABORT_TIMEOUT_MS)))
1178                 return -1;
1179
1180         return 0;
1181
1182 out:
1183         spin_unlock_irq(target->scsi_host->host_lock);
1184         return -1;
1185 }
1186
1187 static int srp_find_req(struct srp_target_port *target,
1188                         struct scsi_cmnd *scmnd,
1189                         struct srp_request **req)
1190 {
1191         if (scmnd->host_scribble == (void *) -1L)
1192                 return -1;
1193
1194         *req = &target->req_ring[(long) scmnd->host_scribble];
1195
1196         return 0;
1197 }
1198
1199 static int srp_abort(struct scsi_cmnd *scmnd)
1200 {
1201         struct srp_target_port *target = host_to_target(scmnd->device->host);
1202         struct srp_request *req;
1203         int ret = SUCCESS;
1204
1205         printk(KERN_ERR "SRP abort called\n");
1206
1207         if (srp_find_req(target, scmnd, &req))
1208                 return FAILED;
1209         if (srp_send_tsk_mgmt(target, req, SRP_TSK_ABORT_TASK))
1210                 return FAILED;
1211
1212         spin_lock_irq(target->scsi_host->host_lock);
1213
1214         if (req->cmd_done) {
1215                 srp_remove_req(target, req);
1216                 scmnd->scsi_done(scmnd);
1217         } else if (!req->tsk_status) {
1218                 srp_remove_req(target, req);
1219                 scmnd->result = DID_ABORT << 16;
1220         } else
1221                 ret = FAILED;
1222
1223         spin_unlock_irq(target->scsi_host->host_lock);
1224
1225         return ret;
1226 }
1227
1228 static int srp_reset_device(struct scsi_cmnd *scmnd)
1229 {
1230         struct srp_target_port *target = host_to_target(scmnd->device->host);
1231         struct srp_request *req, *tmp;
1232
1233         printk(KERN_ERR "SRP reset_device called\n");
1234
1235         if (srp_find_req(target, scmnd, &req))
1236                 return FAILED;
1237         if (srp_send_tsk_mgmt(target, req, SRP_TSK_LUN_RESET))
1238                 return FAILED;
1239         if (req->tsk_status)
1240                 return FAILED;
1241
1242         spin_lock_irq(target->scsi_host->host_lock);
1243
1244         list_for_each_entry_safe(req, tmp, &target->req_queue, list)
1245                 if (req->scmnd->device == scmnd->device) {
1246                         req->scmnd->result = DID_RESET << 16;
1247                         scmnd->scsi_done(scmnd);
1248                         srp_remove_req(target, req);
1249                 }
1250
1251         spin_unlock_irq(target->scsi_host->host_lock);
1252
1253         return SUCCESS;
1254 }
1255
1256 static int srp_reset_host(struct scsi_cmnd *scmnd)
1257 {
1258         struct srp_target_port *target = host_to_target(scmnd->device->host);
1259         int ret = FAILED;
1260
1261         printk(KERN_ERR PFX "SRP reset_host called\n");
1262
1263         if (!srp_reconnect_target(target))
1264                 ret = SUCCESS;
1265
1266         return ret;
1267 }
1268
1269 static ssize_t show_id_ext(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%016llx\n",
1278                        (unsigned long long) be64_to_cpu(target->id_ext));
1279 }
1280
1281 static ssize_t show_ioc_guid(struct class_device *cdev, char *buf)
1282 {
1283         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1284
1285         if (target->state == SRP_TARGET_DEAD ||
1286             target->state == SRP_TARGET_REMOVED)
1287                 return -ENODEV;
1288
1289         return sprintf(buf, "0x%016llx\n",
1290                        (unsigned long long) be64_to_cpu(target->ioc_guid));
1291 }
1292
1293 static ssize_t show_service_id(struct class_device *cdev, char *buf)
1294 {
1295         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1296
1297         if (target->state == SRP_TARGET_DEAD ||
1298             target->state == SRP_TARGET_REMOVED)
1299                 return -ENODEV;
1300
1301         return sprintf(buf, "0x%016llx\n",
1302                        (unsigned long long) be64_to_cpu(target->service_id));
1303 }
1304
1305 static ssize_t show_pkey(struct class_device *cdev, char *buf)
1306 {
1307         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1308
1309         if (target->state == SRP_TARGET_DEAD ||
1310             target->state == SRP_TARGET_REMOVED)
1311                 return -ENODEV;
1312
1313         return sprintf(buf, "0x%04x\n", be16_to_cpu(target->path.pkey));
1314 }
1315
1316 static ssize_t show_dgid(struct class_device *cdev, char *buf)
1317 {
1318         struct srp_target_port *target = host_to_target(class_to_shost(cdev));
1319
1320         if (target->state == SRP_TARGET_DEAD ||
1321             target->state == SRP_TARGET_REMOVED)
1322                 return -ENODEV;
1323
1324         return sprintf(buf, "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1325                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[0]),
1326                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[1]),
1327                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[2]),
1328                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[3]),
1329                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[4]),
1330                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[5]),
1331                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[6]),
1332                        be16_to_cpu(((__be16 *) target->path.dgid.raw)[7]));
1333 }
1334
1335 static CLASS_DEVICE_ATTR(id_ext,        S_IRUGO, show_id_ext,           NULL);
1336 static CLASS_DEVICE_ATTR(ioc_guid,      S_IRUGO, show_ioc_guid,         NULL);
1337 static CLASS_DEVICE_ATTR(service_id,    S_IRUGO, show_service_id,       NULL);
1338 static CLASS_DEVICE_ATTR(pkey,          S_IRUGO, show_pkey,             NULL);
1339 static CLASS_DEVICE_ATTR(dgid,          S_IRUGO, show_dgid,             NULL);
1340
1341 static struct class_device_attribute *srp_host_attrs[] = {
1342         &class_device_attr_id_ext,
1343         &class_device_attr_ioc_guid,
1344         &class_device_attr_service_id,
1345         &class_device_attr_pkey,
1346         &class_device_attr_dgid,
1347         NULL
1348 };
1349
1350 static struct scsi_host_template srp_template = {
1351         .module                         = THIS_MODULE,
1352         .name                           = DRV_NAME,
1353         .info                           = srp_target_info,
1354         .queuecommand                   = srp_queuecommand,
1355         .eh_abort_handler               = srp_abort,
1356         .eh_device_reset_handler        = srp_reset_device,
1357         .eh_host_reset_handler          = srp_reset_host,
1358         .can_queue                      = SRP_SQ_SIZE,
1359         .this_id                        = -1,
1360         .sg_tablesize                   = SRP_MAX_INDIRECT,
1361         .cmd_per_lun                    = SRP_SQ_SIZE,
1362         .use_clustering                 = ENABLE_CLUSTERING,
1363         .shost_attrs                    = srp_host_attrs
1364 };
1365
1366 static int srp_add_target(struct srp_host *host, struct srp_target_port *target)
1367 {
1368         sprintf(target->target_name, "SRP.T10:%016llX",
1369                  (unsigned long long) be64_to_cpu(target->id_ext));
1370
1371         if (scsi_add_host(target->scsi_host, host->dev->dma_device))
1372                 return -ENODEV;
1373
1374         mutex_lock(&host->target_mutex);
1375         list_add_tail(&target->list, &host->target_list);
1376         mutex_unlock(&host->target_mutex);
1377
1378         target->state = SRP_TARGET_LIVE;
1379
1380         /* XXX: are we supposed to have a definition of SCAN_WILD_CARD ?? */
1381         scsi_scan_target(&target->scsi_host->shost_gendev,
1382                          0, target->scsi_id, ~0, 0);
1383
1384         return 0;
1385 }
1386
1387 static void srp_release_class_dev(struct class_device *class_dev)
1388 {
1389         struct srp_host *host =
1390                 container_of(class_dev, struct srp_host, class_dev);
1391
1392         complete(&host->released);
1393 }
1394
1395 static struct class srp_class = {
1396         .name    = "infiniband_srp",
1397         .release = srp_release_class_dev
1398 };
1399
1400 /*
1401  * Target ports are added by writing
1402  *
1403  *     id_ext=<SRP ID ext>,ioc_guid=<SRP IOC GUID>,dgid=<dest GID>,
1404  *     pkey=<P_Key>,service_id=<service ID>
1405  *
1406  * to the add_target sysfs attribute.
1407  */
1408 enum {
1409         SRP_OPT_ERR             = 0,
1410         SRP_OPT_ID_EXT          = 1 << 0,
1411         SRP_OPT_IOC_GUID        = 1 << 1,
1412         SRP_OPT_DGID            = 1 << 2,
1413         SRP_OPT_PKEY            = 1 << 3,
1414         SRP_OPT_SERVICE_ID      = 1 << 4,
1415         SRP_OPT_MAX_SECT        = 1 << 5,
1416         SRP_OPT_ALL             = (SRP_OPT_ID_EXT       |
1417                                    SRP_OPT_IOC_GUID     |
1418                                    SRP_OPT_DGID         |
1419                                    SRP_OPT_PKEY         |
1420                                    SRP_OPT_SERVICE_ID),
1421 };
1422
1423 static match_table_t srp_opt_tokens = {
1424         { SRP_OPT_ID_EXT,       "id_ext=%s"     },
1425         { SRP_OPT_IOC_GUID,     "ioc_guid=%s"   },
1426         { SRP_OPT_DGID,         "dgid=%s"       },
1427         { SRP_OPT_PKEY,         "pkey=%x"       },
1428         { SRP_OPT_SERVICE_ID,   "service_id=%s" },
1429         { SRP_OPT_MAX_SECT,     "max_sect=%d"   },
1430         { SRP_OPT_ERR,          NULL            }
1431 };
1432
1433 static int srp_parse_options(const char *buf, struct srp_target_port *target)
1434 {
1435         char *options, *sep_opt;
1436         char *p;
1437         char dgid[3];
1438         substring_t args[MAX_OPT_ARGS];
1439         int opt_mask = 0;
1440         int token;
1441         int ret = -EINVAL;
1442         int i;
1443
1444         options = kstrdup(buf, GFP_KERNEL);
1445         if (!options)
1446                 return -ENOMEM;
1447
1448         sep_opt = options;
1449         while ((p = strsep(&sep_opt, ",")) != NULL) {
1450                 if (!*p)
1451                         continue;
1452
1453                 token = match_token(p, srp_opt_tokens, args);
1454                 opt_mask |= token;
1455
1456                 switch (token) {
1457                 case SRP_OPT_ID_EXT:
1458                         p = match_strdup(args);
1459                         target->id_ext = cpu_to_be64(simple_strtoull(p, NULL, 16));
1460                         kfree(p);
1461                         break;
1462
1463                 case SRP_OPT_IOC_GUID:
1464                         p = match_strdup(args);
1465                         target->ioc_guid = cpu_to_be64(simple_strtoull(p, NULL, 16));
1466                         kfree(p);
1467                         break;
1468
1469                 case SRP_OPT_DGID:
1470                         p = match_strdup(args);
1471                         if (strlen(p) != 32) {
1472                                 printk(KERN_WARNING PFX "bad dest GID parameter '%s'\n", p);
1473                                 kfree(p);
1474                                 goto out;
1475                         }
1476
1477                         for (i = 0; i < 16; ++i) {
1478                                 strlcpy(dgid, p + i * 2, 3);
1479                                 target->path.dgid.raw[i] = simple_strtoul(dgid, NULL, 16);
1480                         }
1481                         kfree(p);
1482                         break;
1483
1484                 case SRP_OPT_PKEY:
1485                         if (match_hex(args, &token)) {
1486                                 printk(KERN_WARNING PFX "bad P_Key parameter '%s'\n", p);
1487                                 goto out;
1488                         }
1489                         target->path.pkey = cpu_to_be16(token);
1490                         break;
1491
1492                 case SRP_OPT_SERVICE_ID:
1493                         p = match_strdup(args);
1494                         target->service_id = cpu_to_be64(simple_strtoull(p, NULL, 16));
1495                         kfree(p);
1496                         break;
1497
1498                 case SRP_OPT_MAX_SECT:
1499                         if (match_int(args, &token)) {
1500                                 printk(KERN_WARNING PFX "bad max sect parameter '%s'\n", p);
1501                                 goto out;
1502                         }
1503                         target->scsi_host->max_sectors = token;
1504                         break;
1505
1506                 default:
1507                         printk(KERN_WARNING PFX "unknown parameter or missing value "
1508                                "'%s' in target creation request\n", p);
1509                         goto out;
1510                 }
1511         }
1512
1513         if ((opt_mask & SRP_OPT_ALL) == SRP_OPT_ALL)
1514                 ret = 0;
1515         else
1516                 for (i = 0; i < ARRAY_SIZE(srp_opt_tokens); ++i)
1517                         if ((srp_opt_tokens[i].token & SRP_OPT_ALL) &&
1518                             !(srp_opt_tokens[i].token & opt_mask))
1519                                 printk(KERN_WARNING PFX "target creation request is "
1520                                        "missing parameter '%s'\n",
1521                                        srp_opt_tokens[i].pattern);
1522
1523 out:
1524         kfree(options);
1525         return ret;
1526 }
1527
1528 static ssize_t srp_create_target(struct class_device *class_dev,
1529                                  const char *buf, size_t count)
1530 {
1531         struct srp_host *host =
1532                 container_of(class_dev, struct srp_host, class_dev);
1533         struct Scsi_Host *target_host;
1534         struct srp_target_port *target;
1535         int ret;
1536         int i;
1537
1538         target_host = scsi_host_alloc(&srp_template,
1539                                       sizeof (struct srp_target_port));
1540         if (!target_host)
1541                 return -ENOMEM;
1542
1543         target_host->max_lun = SRP_MAX_LUN;
1544
1545         target = host_to_target(target_host);
1546         memset(target, 0, sizeof *target);
1547
1548         target->scsi_host  = target_host;
1549         target->srp_host   = host;
1550
1551         INIT_WORK(&target->work, srp_reconnect_work, target);
1552
1553         INIT_LIST_HEAD(&target->free_reqs);
1554         INIT_LIST_HEAD(&target->req_queue);
1555         for (i = 0; i < SRP_SQ_SIZE; ++i) {
1556                 target->req_ring[i].index = i;
1557                 list_add_tail(&target->req_ring[i].list, &target->free_reqs);
1558         }
1559
1560         ret = srp_parse_options(buf, target);
1561         if (ret)
1562                 goto err;
1563
1564         ib_get_cached_gid(host->dev, host->port, 0, &target->path.sgid);
1565
1566         printk(KERN_DEBUG PFX "new target: id_ext %016llx ioc_guid %016llx pkey %04x "
1567                "service_id %016llx dgid %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
1568                (unsigned long long) be64_to_cpu(target->id_ext),
1569                (unsigned long long) be64_to_cpu(target->ioc_guid),
1570                be16_to_cpu(target->path.pkey),
1571                (unsigned long long) be64_to_cpu(target->service_id),
1572                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[0]),
1573                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[2]),
1574                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[4]),
1575                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[6]),
1576                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[8]),
1577                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[10]),
1578                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[12]),
1579                (int) be16_to_cpu(*(__be16 *) &target->path.dgid.raw[14]));
1580
1581         ret = srp_create_target_ib(target);
1582         if (ret)
1583                 goto err;
1584
1585         target->cm_id = ib_create_cm_id(host->dev, srp_cm_handler, target);
1586         if (IS_ERR(target->cm_id)) {
1587                 ret = PTR_ERR(target->cm_id);
1588                 goto err_free;
1589         }
1590
1591         ret = srp_connect_target(target);
1592         if (ret) {
1593                 printk(KERN_ERR PFX "Connection failed\n");
1594                 goto err_cm_id;
1595         }
1596
1597         ret = srp_add_target(host, target);
1598         if (ret)
1599                 goto err_disconnect;
1600
1601         return count;
1602
1603 err_disconnect:
1604         srp_disconnect_target(target);
1605
1606 err_cm_id:
1607         ib_destroy_cm_id(target->cm_id);
1608
1609 err_free:
1610         srp_free_target_ib(target);
1611
1612 err:
1613         scsi_host_put(target_host);
1614
1615         return ret;
1616 }
1617
1618 static CLASS_DEVICE_ATTR(add_target, S_IWUSR, NULL, srp_create_target);
1619
1620 static ssize_t show_ibdev(struct class_device *class_dev, char *buf)
1621 {
1622         struct srp_host *host =
1623                 container_of(class_dev, struct srp_host, class_dev);
1624
1625         return sprintf(buf, "%s\n", host->dev->name);
1626 }
1627
1628 static CLASS_DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1629
1630 static ssize_t show_port(struct class_device *class_dev, char *buf)
1631 {
1632         struct srp_host *host =
1633                 container_of(class_dev, struct srp_host, class_dev);
1634
1635         return sprintf(buf, "%d\n", host->port);
1636 }
1637
1638 static CLASS_DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
1639
1640 static struct srp_host *srp_add_port(struct ib_device *device, u8 port)
1641 {
1642         struct srp_host *host;
1643
1644         host = kzalloc(sizeof *host, GFP_KERNEL);
1645         if (!host)
1646                 return NULL;
1647
1648         INIT_LIST_HEAD(&host->target_list);
1649         mutex_init(&host->target_mutex);
1650         init_completion(&host->released);
1651         host->dev  = device;
1652         host->port = port;
1653
1654         host->initiator_port_id[7] = port;
1655         memcpy(host->initiator_port_id + 8, &device->node_guid, 8);
1656
1657         host->pd   = ib_alloc_pd(device);
1658         if (IS_ERR(host->pd))
1659                 goto err_free;
1660
1661         host->mr   = ib_get_dma_mr(host->pd,
1662                                    IB_ACCESS_LOCAL_WRITE |
1663                                    IB_ACCESS_REMOTE_READ |
1664                                    IB_ACCESS_REMOTE_WRITE);
1665         if (IS_ERR(host->mr))
1666                 goto err_pd;
1667
1668         host->class_dev.class = &srp_class;
1669         host->class_dev.dev   = device->dma_device;
1670         snprintf(host->class_dev.class_id, BUS_ID_SIZE, "srp-%s-%d",
1671                  device->name, port);
1672
1673         if (class_device_register(&host->class_dev))
1674                 goto err_mr;
1675         if (class_device_create_file(&host->class_dev, &class_device_attr_add_target))
1676                 goto err_class;
1677         if (class_device_create_file(&host->class_dev, &class_device_attr_ibdev))
1678                 goto err_class;
1679         if (class_device_create_file(&host->class_dev, &class_device_attr_port))
1680                 goto err_class;
1681
1682         return host;
1683
1684 err_class:
1685         class_device_unregister(&host->class_dev);
1686
1687 err_mr:
1688         ib_dereg_mr(host->mr);
1689
1690 err_pd:
1691         ib_dealloc_pd(host->pd);
1692
1693 err_free:
1694         kfree(host);
1695
1696         return NULL;
1697 }
1698
1699 static void srp_add_one(struct ib_device *device)
1700 {
1701         struct list_head *dev_list;
1702         struct srp_host *host;
1703         int s, e, p;
1704
1705         dev_list = kmalloc(sizeof *dev_list, GFP_KERNEL);
1706         if (!dev_list)
1707                 return;
1708
1709         INIT_LIST_HEAD(dev_list);
1710
1711         if (device->node_type == IB_NODE_SWITCH) {
1712                 s = 0;
1713                 e = 0;
1714         } else {
1715                 s = 1;
1716                 e = device->phys_port_cnt;
1717         }
1718
1719         for (p = s; p <= e; ++p) {
1720                 host = srp_add_port(device, p);
1721                 if (host)
1722                         list_add_tail(&host->list, dev_list);
1723         }
1724
1725         ib_set_client_data(device, &srp_client, dev_list);
1726 }
1727
1728 static void srp_remove_one(struct ib_device *device)
1729 {
1730         struct list_head *dev_list;
1731         struct srp_host *host, *tmp_host;
1732         LIST_HEAD(target_list);
1733         struct srp_target_port *target, *tmp_target;
1734         unsigned long flags;
1735
1736         dev_list = ib_get_client_data(device, &srp_client);
1737
1738         list_for_each_entry_safe(host, tmp_host, dev_list, list) {
1739                 class_device_unregister(&host->class_dev);
1740                 /*
1741                  * Wait for the sysfs entry to go away, so that no new
1742                  * target ports can be created.
1743                  */
1744                 wait_for_completion(&host->released);
1745
1746                 /*
1747                  * Mark all target ports as removed, so we stop queueing
1748                  * commands and don't try to reconnect.
1749                  */
1750                 mutex_lock(&host->target_mutex);
1751                 list_for_each_entry_safe(target, tmp_target,
1752                                          &host->target_list, list) {
1753                         spin_lock_irqsave(target->scsi_host->host_lock, flags);
1754                         if (target->state != SRP_TARGET_REMOVED)
1755                                 target->state = SRP_TARGET_REMOVED;
1756                         spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
1757                 }
1758                 mutex_unlock(&host->target_mutex);
1759
1760                 /*
1761                  * Wait for any reconnection tasks that may have
1762                  * started before we marked our target ports as
1763                  * removed, and any target port removal tasks.
1764                  */
1765                 flush_scheduled_work();
1766
1767                 list_for_each_entry_safe(target, tmp_target,
1768                                          &host->target_list, list) {
1769                         scsi_remove_host(target->scsi_host);
1770                         srp_disconnect_target(target);
1771                         ib_destroy_cm_id(target->cm_id);
1772                         srp_free_target_ib(target);
1773                         scsi_host_put(target->scsi_host);
1774                 }
1775
1776                 ib_dereg_mr(host->mr);
1777                 ib_dealloc_pd(host->pd);
1778                 kfree(host);
1779         }
1780
1781         kfree(dev_list);
1782 }
1783
1784 static int __init srp_init_module(void)
1785 {
1786         int ret;
1787
1788         ret = class_register(&srp_class);
1789         if (ret) {
1790                 printk(KERN_ERR PFX "couldn't register class infiniband_srp\n");
1791                 return ret;
1792         }
1793
1794         ret = ib_register_client(&srp_client);
1795         if (ret) {
1796                 printk(KERN_ERR PFX "couldn't register IB client\n");
1797                 class_unregister(&srp_class);
1798                 return ret;
1799         }
1800
1801         return 0;
1802 }
1803
1804 static void __exit srp_cleanup_module(void)
1805 {
1806         ib_unregister_client(&srp_client);
1807         class_unregister(&srp_class);
1808 }
1809
1810 module_init(srp_init_module);
1811 module_exit(srp_cleanup_module);