drivers/target/loopback/tcm_loop.c

   1 /*******************************************************************************
   2  *
   3  * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4  * for emulated SAS initiator ports
   5  *
   6  * © Copyright 2011-2013 Datera, Inc.
   7  *
   8  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9  *
  10  * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  ****************************************************************************/
  22
  23 #include <linux/module.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/init.h>
  26 #include <linux/slab.h>
  27 #include <linux/types.h>
  28 #include <linux/configfs.h>
  29 #include <scsi/scsi.h>
  30 #include <scsi/scsi_tcq.h>
  31 #include <scsi/scsi_host.h>
  32 #include <scsi/scsi_device.h>
  33 #include <scsi/scsi_cmnd.h>
  34
  35 #include <target/target_core_base.h>
  36 #include <target/target_core_fabric.h>
  37
  38 #include "tcm_loop.h"
  39
  40 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
  41
  42 static struct workqueue_struct *tcm_loop_workqueue;
  43 static struct kmem_cache *tcm_loop_cmd_cache;
  44
  45 static int tcm_loop_hba_no_cnt;
  46
  47 static int tcm_loop_queue_status(struct se_cmd *se_cmd);
  48
  49 /*
  50  * Called from struct target_core_fabric_ops->check_stop_free()
  51  */
  52 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  53 {
  54         return transport_generic_free_cmd(se_cmd, 0);
  55 }
  56
  57 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  58 {
  59         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  60                                 struct tcm_loop_cmd, tl_se_cmd);
  61
  62         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  63 }
  64
  65 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  66 {
  67         seq_puts(m, "tcm_loop_proc_info()\n");
  68         return 0;
  69 }
  70
  71 static int tcm_loop_driver_probe(struct device *);
  72 static int tcm_loop_driver_remove(struct device *);
  73
  74 static int pseudo_lld_bus_match(struct device *dev,
  75                                 struct device_driver *dev_driver)
  76 {
  77         return 1;
  78 }
  79
  80 static struct bus_type tcm_loop_lld_bus = {
  81         .name                   = "tcm_loop_bus",
  82         .match                  = pseudo_lld_bus_match,
  83         .probe                  = tcm_loop_driver_probe,
  84         .remove                 = tcm_loop_driver_remove,
  85 };
  86
  87 static struct device_driver tcm_loop_driverfs = {
  88         .name                   = "tcm_loop",
  89         .bus                    = &tcm_loop_lld_bus,
  90 };
  91 /*
  92  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
  93  */
  94 static struct device *tcm_loop_primary;
  95
  96 static void tcm_loop_submission_work(struct work_struct *work)
  97 {
  98         struct tcm_loop_cmd *tl_cmd =
  99                 container_of(work, struct tcm_loop_cmd, work);
 100         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 101         struct scsi_cmnd *sc = tl_cmd->sc;
 102         struct tcm_loop_nexus *tl_nexus;
 103         struct tcm_loop_hba *tl_hba;
 104         struct tcm_loop_tpg *tl_tpg;
 105         struct scatterlist *sgl_bidi = NULL;
 106         u32 sgl_bidi_count = 0, transfer_length;
 107         int rc;
 108
 109         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 110         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 111
 112         /*
 113          * Ensure that this tl_tpg reference from the incoming sc->device->id
 114          * has already been configured via tcm_loop_make_naa_tpg().
 115          */
 116         if (!tl_tpg->tl_hba) {
 117                 set_host_byte(sc, DID_NO_CONNECT);
 118                 goto out_done;
 119         }
 120         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 121                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 122                 goto out_done;
 123         }
 124         tl_nexus = tl_tpg->tl_nexus;
 125         if (!tl_nexus) {
 126                 scmd_printk(KERN_ERR, sc,
 127                             "TCM_Loop I_T Nexus does not exist\n");
 128                 set_host_byte(sc, DID_ERROR);
 129                 goto out_done;
 130         }
 131
 132         transfer_length = scsi_transfer_length(sc);
 133         if (!scsi_prot_sg_count(sc) &&
 134             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 135                 se_cmd->prot_pto = true;
 136                 /*
 137                  * loopback transport doesn't support
 138                  * WRITE_GENERATE, READ_STRIP protection
 139                  * information operations, go ahead unprotected.
 140                  */
 141                 transfer_length = scsi_bufflen(sc);
 142         }
 143
 144         se_cmd->tag = tl_cmd->sc_cmd_tag;
 145         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 146                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 147                         transfer_length, TCM_SIMPLE_TAG,
 148                         sc->sc_data_direction, 0,
 149                         scsi_sglist(sc), scsi_sg_count(sc),
 150                         sgl_bidi, sgl_bidi_count,
 151                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 152         if (rc < 0) {
 153                 set_host_byte(sc, DID_NO_CONNECT);
 154                 goto out_done;
 155         }
 156         return;
 157
 158 out_done:
 159         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 160         sc->scsi_done(sc);
 161 }
 162
 163 /*
 164  * ->queuecommand can be and usually is called from interrupt context, so
 165  * defer the actual submission to a workqueue.
 166  */
 167 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 168 {
 169         struct tcm_loop_cmd *tl_cmd;
 170
 171         pr_debug("%s() %d:%d:%d:%llu got CDB: 0x%02x scsi_buf_len: %u\n",
 172                  __func__, sc->device->host->host_no, sc->device->id,
 173                  sc->device->channel, sc->device->lun, sc->cmnd[0],
 174                  scsi_bufflen(sc));
 175
 176         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 177         if (!tl_cmd) {
 178                 set_host_byte(sc, DID_ERROR);
 179                 sc->scsi_done(sc);
 180                 return 0;
 181         }
 182
 183         tl_cmd->sc = sc;
 184         tl_cmd->sc_cmd_tag = sc->request->tag;
 185         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 186         queue_work(tcm_loop_workqueue, &tl_cmd->work);
 187         return 0;
 188 }
 189
 190 /*
 191  * Called from SCSI EH process context to issue a LUN_RESET TMR
 192  * to struct scsi_device
 193  */
 194 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 195                               u64 lun, int task, enum tcm_tmreq_table tmr)
 196 {
 197         struct se_cmd *se_cmd;
 198         struct se_session *se_sess;
 199         struct tcm_loop_nexus *tl_nexus;
 200         struct tcm_loop_cmd *tl_cmd;
 201         int ret = TMR_FUNCTION_FAILED, rc;
 202
 203         /*
 204          * Locate the tl_nexus and se_sess pointers
 205          */
 206         tl_nexus = tl_tpg->tl_nexus;
 207         if (!tl_nexus) {
 208                 pr_err("Unable to perform device reset without active I_T Nexus\n");
 209                 return ret;
 210         }
 211
 212         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 213         if (!tl_cmd)
 214                 return ret;
 215
 216         init_completion(&tl_cmd->tmr_done);
 217
 218         se_cmd = &tl_cmd->tl_se_cmd;
 219         se_sess = tl_tpg->tl_nexus->se_sess;
 220
 221         rc = target_submit_tmr(se_cmd, se_sess, tl_cmd->tl_sense_buf, lun,
 222                                NULL, tmr, GFP_KERNEL, task,
 223                                TARGET_SCF_ACK_KREF);
 224         if (rc < 0)
 225                 goto release;
 226         wait_for_completion(&tl_cmd->tmr_done);
 227         ret = se_cmd->se_tmr_req->response;
 228         target_put_sess_cmd(se_cmd);
 229
 230 out:
 231         return ret;
 232
 233 release:
 234         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 235         goto out;
 236 }
 237
 238 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 239 {
 240         struct tcm_loop_hba *tl_hba;
 241         struct tcm_loop_tpg *tl_tpg;
 242         int ret = FAILED;
 243
 244         /*
 245          * Locate the tcm_loop_hba_t pointer
 246          */
 247         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 248         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 249         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 250                                  sc->request->tag, TMR_ABORT_TASK);
 251         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 252 }
 253
 254 /*
 255  * Called from SCSI EH process context to issue a LUN_RESET TMR
 256  * to struct scsi_device
 257  */
 258 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 259 {
 260         struct tcm_loop_hba *tl_hba;
 261         struct tcm_loop_tpg *tl_tpg;
 262         int ret = FAILED;
 263
 264         /*
 265          * Locate the tcm_loop_hba_t pointer
 266          */
 267         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 268         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 269
 270         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 271                                  0, TMR_LUN_RESET);
 272         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 273 }
 274
 275 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 276 {
 277         struct tcm_loop_hba *tl_hba;
 278         struct tcm_loop_tpg *tl_tpg;
 279
 280         /*
 281          * Locate the tcm_loop_hba_t pointer
 282          */
 283         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 284         if (!tl_hba) {
 285                 pr_err("Unable to perform device reset without active I_T Nexus\n");
 286                 return FAILED;
 287         }
 288         /*
 289          * Locate the tl_tpg pointer from TargetID in sc->device->id
 290          */
 291         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 292         if (tl_tpg) {
 293                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 294                 return SUCCESS;
 295         }
 296         return FAILED;
 297 }
 298
 299 static struct scsi_host_template tcm_loop_driver_template = {
 300         .show_info              = tcm_loop_show_info,
 301         .proc_name              = "tcm_loopback",
 302         .name                   = "TCM_Loopback",
 303         .queuecommand           = tcm_loop_queuecommand,
 304         .change_queue_depth     = scsi_change_queue_depth,
 305         .eh_abort_handler = tcm_loop_abort_task,
 306         .eh_device_reset_handler = tcm_loop_device_reset,
 307         .eh_target_reset_handler = tcm_loop_target_reset,
 308         .can_queue              = 1024,
 309         .this_id                = -1,
 310         .sg_tablesize           = 256,
 311         .cmd_per_lun            = 1024,
 312         .max_sectors            = 0xFFFF,
 313         .dma_boundary           = PAGE_SIZE - 1,
 314         .module                 = THIS_MODULE,
 315         .track_queue_depth      = 1,
 316 };
 317
 318 static int tcm_loop_driver_probe(struct device *dev)
 319 {
 320         struct tcm_loop_hba *tl_hba;
 321         struct Scsi_Host *sh;
 322         int error, host_prot;
 323
 324         tl_hba = to_tcm_loop_hba(dev);
 325
 326         sh = scsi_host_alloc(&tcm_loop_driver_template,
 327                         sizeof(struct tcm_loop_hba));
 328         if (!sh) {
 329                 pr_err("Unable to allocate struct scsi_host\n");
 330                 return -ENODEV;
 331         }
 332         tl_hba->sh = sh;
 333
 334         /*
 335          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 336          */
 337         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 338         /*
 339          * Setup single ID, Channel and LUN for now..
 340          */
 341         sh->max_id = 2;
 342         sh->max_lun = 0;
 343         sh->max_channel = 0;
 344         sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 345
 346         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 347                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 348                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 349
 350         scsi_host_set_prot(sh, host_prot);
 351         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 352
 353         error = scsi_add_host(sh, &tl_hba->dev);
 354         if (error) {
 355                 pr_err("%s: scsi_add_host failed\n", __func__);
 356                 scsi_host_put(sh);
 357                 return -ENODEV;
 358         }
 359         return 0;
 360 }
 361
 362 static int tcm_loop_driver_remove(struct device *dev)
 363 {
 364         struct tcm_loop_hba *tl_hba;
 365         struct Scsi_Host *sh;
 366
 367         tl_hba = to_tcm_loop_hba(dev);
 368         sh = tl_hba->sh;
 369
 370         scsi_remove_host(sh);
 371         scsi_host_put(sh);
 372         return 0;
 373 }
 374
 375 static void tcm_loop_release_adapter(struct device *dev)
 376 {
 377         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 378
 379         kfree(tl_hba);
 380 }
 381
 382 /*
 383  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 384  */
 385 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 386 {
 387         int ret;
 388
 389         tl_hba->dev.bus = &tcm_loop_lld_bus;
 390         tl_hba->dev.parent = tcm_loop_primary;
 391         tl_hba->dev.release = &tcm_loop_release_adapter;
 392         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 393
 394         ret = device_register(&tl_hba->dev);
 395         if (ret) {
 396                 pr_err("device_register() failed for tl_hba->dev: %d\n", ret);
 397                 return -ENODEV;
 398         }
 399
 400         return 0;
 401 }
 402
 403 /*
 404  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 405  * tcm_loop SCSI bus.
 406  */
 407 static int tcm_loop_alloc_core_bus(void)
 408 {
 409         int ret;
 410
 411         tcm_loop_primary = root_device_register("tcm_loop_0");
 412         if (IS_ERR(tcm_loop_primary)) {
 413                 pr_err("Unable to allocate tcm_loop_primary\n");
 414                 return PTR_ERR(tcm_loop_primary);
 415         }
 416
 417         ret = bus_register(&tcm_loop_lld_bus);
 418         if (ret) {
 419                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 420                 goto dev_unreg;
 421         }
 422
 423         ret = driver_register(&tcm_loop_driverfs);
 424         if (ret) {
 425                 pr_err("driver_register() failed for tcm_loop_driverfs\n");
 426                 goto bus_unreg;
 427         }
 428
 429         pr_debug("Initialized TCM Loop Core Bus\n");
 430         return ret;
 431
 432 bus_unreg:
 433         bus_unregister(&tcm_loop_lld_bus);
 434 dev_unreg:
 435         root_device_unregister(tcm_loop_primary);
 436         return ret;
 437 }
 438
 439 static void tcm_loop_release_core_bus(void)
 440 {
 441         driver_unregister(&tcm_loop_driverfs);
 442         bus_unregister(&tcm_loop_lld_bus);
 443         root_device_unregister(tcm_loop_primary);
 444
 445         pr_debug("Releasing TCM Loop Core BUS\n");
 446 }
 447
 448 static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
 449 {
 450         return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 451 }
 452
 453 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 454 {
 455         /*
 456          * Return the passed NAA identifier for the Target Port
 457          */
 458         return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
 459 }
 460
 461 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 462 {
 463         /*
 464          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 465          * to represent the SCSI Target Port.
 466          */
 467         return tl_tpg(se_tpg)->tl_tpgt;
 468 }
 469
 470 /*
 471  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 472  * based upon the incoming fabric dependent SCSI Initiator Port
 473  */
 474 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 475 {
 476         return 1;
 477 }
 478
 479 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 480 {
 481         return 0;
 482 }
 483
 484 /*
 485  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 486  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 487  */
 488 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 489 {
 490         return 0;
 491 }
 492
 493 /*
 494  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 495  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 496  * It has been added here as a nop for target_fabric_tf_ops_check()
 497  */
 498 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 499 {
 500         return 0;
 501 }
 502
 503 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
 504 {
 505         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 506                                                    tl_se_tpg);
 507         return tl_tpg->tl_fabric_prot_type;
 508 }
 509
 510 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 511 {
 512         return 1;
 513 }
 514
 515 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 516 {
 517         return 1;
 518 }
 519
 520 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 521 {
 522         return;
 523 }
 524
 525 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 526 {
 527         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 528                         struct tcm_loop_cmd, tl_se_cmd);
 529
 530         return tl_cmd->sc_cmd_state;
 531 }
 532
 533 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 534 {
 535         /*
 536          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 537          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 538          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 539          * format with transport_generic_map_mem_to_cmd().
 540          *
 541          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 542          * object execution queue.
 543          */
 544         target_execute_cmd(se_cmd);
 545         return 0;
 546 }
 547
 548 static int tcm_loop_queue_data_or_status(const char *func,
 549                 struct se_cmd *se_cmd, u8 scsi_status)
 550 {
 551         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 552                                 struct tcm_loop_cmd, tl_se_cmd);
 553         struct scsi_cmnd *sc = tl_cmd->sc;
 554
 555         pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
 556                  func, sc, sc->cmnd[0]);
 557
 558         if (se_cmd->sense_buffer &&
 559            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 560             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 561
 562                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 563                                 SCSI_SENSE_BUFFERSIZE);
 564                 sc->result = SAM_STAT_CHECK_CONDITION;
 565                 set_driver_byte(sc, DRIVER_SENSE);
 566         } else
 567                 sc->result = scsi_status;
 568
 569         set_host_byte(sc, DID_OK);
 570         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 571             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 572                 scsi_set_resid(sc, se_cmd->residual_count);
 573         sc->scsi_done(sc);
 574         return 0;
 575 }
 576
 577 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 578 {
 579         return tcm_loop_queue_data_or_status(__func__, se_cmd, SAM_STAT_GOOD);
 580 }
 581
 582 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 583 {
 584         return tcm_loop_queue_data_or_status(__func__,
 585                                              se_cmd, se_cmd->scsi_status);
 586 }
 587
 588 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 589 {
 590         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 591                                 struct tcm_loop_cmd, tl_se_cmd);
 592
 593         /* Wake up tcm_loop_issue_tmr(). */
 594         complete(&tl_cmd->tmr_done);
 595 }
 596
 597 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 598 {
 599         return;
 600 }
 601
 602 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 603 {
 604         switch (tl_hba->tl_proto_id) {
 605         case SCSI_PROTOCOL_SAS:
 606                 return "SAS";
 607         case SCSI_PROTOCOL_FCP:
 608                 return "FCP";
 609         case SCSI_PROTOCOL_ISCSI:
 610                 return "iSCSI";
 611         default:
 612                 break;
 613         }
 614
 615         return "Unknown";
 616 }
 617
 618 /* Start items for tcm_loop_port_cit */
 619
 620 static int tcm_loop_port_link(
 621         struct se_portal_group *se_tpg,
 622         struct se_lun *lun)
 623 {
 624         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 625                                 struct tcm_loop_tpg, tl_se_tpg);
 626         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 627
 628         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 629         /*
 630          * Add Linux/SCSI struct scsi_device by HCTL
 631          */
 632         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 633
 634         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 635         return 0;
 636 }
 637
 638 static void tcm_loop_port_unlink(
 639         struct se_portal_group *se_tpg,
 640         struct se_lun *se_lun)
 641 {
 642         struct scsi_device *sd;
 643         struct tcm_loop_hba *tl_hba;
 644         struct tcm_loop_tpg *tl_tpg;
 645
 646         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 647         tl_hba = tl_tpg->tl_hba;
 648
 649         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 650                                 se_lun->unpacked_lun);
 651         if (!sd) {
 652                 pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n",
 653                        0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 654                 return;
 655         }
 656         /*
 657          * Remove Linux/SCSI struct scsi_device by HCTL
 658          */
 659         scsi_remove_device(sd);
 660         scsi_device_put(sd);
 661
 662         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 663
 664         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 665 }
 666
 667 /* End items for tcm_loop_port_cit */
 668
 669 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
 670                 struct config_item *item, char *page)
 671 {
 672         struct se_portal_group *se_tpg = attrib_to_tpg(item);
 673         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 674                                                    tl_se_tpg);
 675
 676         return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
 677 }
 678
 679 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
 680                 struct config_item *item, const char *page, size_t count)
 681 {
 682         struct se_portal_group *se_tpg = attrib_to_tpg(item);
 683         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 684                                                    tl_se_tpg);
 685         unsigned long val;
 686         int ret = kstrtoul(page, 0, &val);
 687
 688         if (ret) {
 689                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
 690                 return ret;
 691         }
 692         if (val != 0 && val != 1 && val != 3) {
 693                 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
 694                 return -EINVAL;
 695         }
 696         tl_tpg->tl_fabric_prot_type = val;
 697
 698         return count;
 699 }
 700
 701 CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
 702
 703 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
 704         &tcm_loop_tpg_attrib_attr_fabric_prot_type,
 705         NULL,
 706 };
 707
 708 /* Start items for tcm_loop_nexus_cit */
 709
 710 static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
 711                                   struct se_session *se_sess, void *p)
 712 {
 713         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 714                                         struct tcm_loop_tpg, tl_se_tpg);
 715
 716         tl_tpg->tl_nexus = p;
 717         return 0;
 718 }
 719
 720 static int tcm_loop_make_nexus(
 721         struct tcm_loop_tpg *tl_tpg,
 722         const char *name)
 723 {
 724         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 725         struct tcm_loop_nexus *tl_nexus;
 726         int ret;
 727
 728         if (tl_tpg->tl_nexus) {
 729                 pr_debug("tl_tpg->tl_nexus already exists\n");
 730                 return -EEXIST;
 731         }
 732
 733         tl_nexus = kzalloc(sizeof(*tl_nexus), GFP_KERNEL);
 734         if (!tl_nexus)
 735                 return -ENOMEM;
 736
 737         tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0,
 738                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
 739                                         name, tl_nexus, tcm_loop_alloc_sess_cb);
 740         if (IS_ERR(tl_nexus->se_sess)) {
 741                 ret = PTR_ERR(tl_nexus->se_sess);
 742                 kfree(tl_nexus);
 743                 return ret;
 744         }
 745
 746         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n",
 747                  tcm_loop_dump_proto_id(tl_hba), name);
 748         return 0;
 749 }
 750
 751 static int tcm_loop_drop_nexus(
 752         struct tcm_loop_tpg *tpg)
 753 {
 754         struct se_session *se_sess;
 755         struct tcm_loop_nexus *tl_nexus;
 756
 757         tl_nexus = tpg->tl_nexus;
 758         if (!tl_nexus)
 759                 return -ENODEV;
 760
 761         se_sess = tl_nexus->se_sess;
 762         if (!se_sess)
 763                 return -ENODEV;
 764
 765         if (atomic_read(&tpg->tl_tpg_port_count)) {
 766                 pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n",
 767                        atomic_read(&tpg->tl_tpg_port_count));
 768                 return -EPERM;
 769         }
 770
 771         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
 772                  tcm_loop_dump_proto_id(tpg->tl_hba),
 773                  tl_nexus->se_sess->se_node_acl->initiatorname);
 774         /*
 775          * Release the SCSI I_T Nexus to the emulated Target Port
 776          */
 777         target_remove_session(se_sess);
 778         tpg->tl_nexus = NULL;
 779         kfree(tl_nexus);
 780         return 0;
 781 }
 782
 783 /* End items for tcm_loop_nexus_cit */
 784
 785 static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
 786 {
 787         struct se_portal_group *se_tpg = to_tpg(item);
 788         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 789                         struct tcm_loop_tpg, tl_se_tpg);
 790         struct tcm_loop_nexus *tl_nexus;
 791         ssize_t ret;
 792
 793         tl_nexus = tl_tpg->tl_nexus;
 794         if (!tl_nexus)
 795                 return -ENODEV;
 796
 797         ret = snprintf(page, PAGE_SIZE, "%s\n",
 798                 tl_nexus->se_sess->se_node_acl->initiatorname);
 799
 800         return ret;
 801 }
 802
 803 static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
 804                 const char *page, size_t count)
 805 {
 806         struct se_portal_group *se_tpg = to_tpg(item);
 807         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 808                         struct tcm_loop_tpg, tl_se_tpg);
 809         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 810         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
 811         int ret;
 812         /*
 813          * Shutdown the active I_T nexus if 'NULL' is passed..
 814          */
 815         if (!strncmp(page, "NULL", 4)) {
 816                 ret = tcm_loop_drop_nexus(tl_tpg);
 817                 return (!ret) ? count : ret;
 818         }
 819         /*
 820          * Otherwise make sure the passed virtual Initiator port WWN matches
 821          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
 822          * tcm_loop_make_nexus()
 823          */
 824         if (strlen(page) >= TL_WWN_ADDR_LEN) {
 825                 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
 826                        page, TL_WWN_ADDR_LEN);
 827                 return -EINVAL;
 828         }
 829         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
 830
 831         ptr = strstr(i_port, "naa.");
 832         if (ptr) {
 833                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
 834                         pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
 835                                i_port, tcm_loop_dump_proto_id(tl_hba));
 836                         return -EINVAL;
 837                 }
 838                 port_ptr = &i_port[0];
 839                 goto check_newline;
 840         }
 841         ptr = strstr(i_port, "fc.");
 842         if (ptr) {
 843                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
 844                         pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
 845                                i_port, tcm_loop_dump_proto_id(tl_hba));
 846                         return -EINVAL;
 847                 }
 848                 port_ptr = &i_port[3]; /* Skip over "fc." */
 849                 goto check_newline;
 850         }
 851         ptr = strstr(i_port, "iqn.");
 852         if (ptr) {
 853                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
 854                         pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
 855                                i_port, tcm_loop_dump_proto_id(tl_hba));
 856                         return -EINVAL;
 857                 }
 858                 port_ptr = &i_port[0];
 859                 goto check_newline;
 860         }
 861         pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
 862                i_port);
 863         return -EINVAL;
 864         /*
 865          * Clear any trailing newline for the NAA WWN
 866          */
 867 check_newline:
 868         if (i_port[strlen(i_port)-1] == '\n')
 869                 i_port[strlen(i_port)-1] = '\0';
 870
 871         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
 872         if (ret < 0)
 873                 return ret;
 874
 875         return count;
 876 }
 877
 878 static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
 879                 char *page)
 880 {
 881         struct se_portal_group *se_tpg = to_tpg(item);
 882         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 883                         struct tcm_loop_tpg, tl_se_tpg);
 884         const char *status = NULL;
 885         ssize_t ret = -EINVAL;
 886
 887         switch (tl_tpg->tl_transport_status) {
 888         case TCM_TRANSPORT_ONLINE:
 889                 status = "online";
 890                 break;
 891         case TCM_TRANSPORT_OFFLINE:
 892                 status = "offline";
 893                 break;
 894         default:
 895                 break;
 896         }
 897
 898         if (status)
 899                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
 900
 901         return ret;
 902 }
 903
 904 static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
 905                 const char *page, size_t count)
 906 {
 907         struct se_portal_group *se_tpg = to_tpg(item);
 908         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 909                         struct tcm_loop_tpg, tl_se_tpg);
 910
 911         if (!strncmp(page, "online", 6)) {
 912                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 913                 return count;
 914         }
 915         if (!strncmp(page, "offline", 7)) {
 916                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
 917                 if (tl_tpg->tl_nexus) {
 918                         struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
 919
 920                         core_allocate_nexus_loss_ua(tl_sess->se_node_acl);
 921                 }
 922                 return count;
 923         }
 924         return -EINVAL;
 925 }
 926
 927 static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
 928                                          char *page)
 929 {
 930         struct se_portal_group *se_tpg = to_tpg(item);
 931         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 932                         struct tcm_loop_tpg, tl_se_tpg);
 933         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 934
 935         return snprintf(page, PAGE_SIZE, "%d:0:%d\n",
 936                         tl_hba->sh->host_no, tl_tpg->tl_tpgt);
 937 }
 938
 939 CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
 940 CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
 941 CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
 942
 943 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
 944         &tcm_loop_tpg_attr_nexus,
 945         &tcm_loop_tpg_attr_transport_status,
 946         &tcm_loop_tpg_attr_address,
 947         NULL,
 948 };
 949
 950 /* Start items for tcm_loop_naa_cit */
 951
 952 static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn,
 953                                                      const char *name)
 954 {
 955         struct tcm_loop_hba *tl_hba = container_of(wwn,
 956                         struct tcm_loop_hba, tl_hba_wwn);
 957         struct tcm_loop_tpg *tl_tpg;
 958         int ret;
 959         unsigned long tpgt;
 960
 961         if (strstr(name, "tpgt_") != name) {
 962                 pr_err("Unable to locate \"tpgt_#\" directory group\n");
 963                 return ERR_PTR(-EINVAL);
 964         }
 965         if (kstrtoul(name+5, 10, &tpgt))
 966                 return ERR_PTR(-EINVAL);
 967
 968         if (tpgt >= TL_TPGS_PER_HBA) {
 969                 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
 970                        tpgt, TL_TPGS_PER_HBA);
 971                 return ERR_PTR(-EINVAL);
 972         }
 973         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
 974         tl_tpg->tl_hba = tl_hba;
 975         tl_tpg->tl_tpgt = tpgt;
 976         /*
 977          * Register the tl_tpg as a emulated TCM Target Endpoint
 978          */
 979         ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
 980         if (ret < 0)
 981                 return ERR_PTR(-ENOMEM);
 982
 983         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
 984                  tcm_loop_dump_proto_id(tl_hba),
 985                  config_item_name(&wwn->wwn_group.cg_item), tpgt);
 986         return &tl_tpg->tl_se_tpg;
 987 }
 988
 989 static void tcm_loop_drop_naa_tpg(
 990         struct se_portal_group *se_tpg)
 991 {
 992         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
 993         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 994                                 struct tcm_loop_tpg, tl_se_tpg);
 995         struct tcm_loop_hba *tl_hba;
 996         unsigned short tpgt;
 997
 998         tl_hba = tl_tpg->tl_hba;
 999         tpgt = tl_tpg->tl_tpgt;
1000         /*
1001          * Release the I_T Nexus for the Virtual target link if present
1002          */
1003         tcm_loop_drop_nexus(tl_tpg);
1004         /*
1005          * Deregister the tl_tpg as a emulated TCM Target Endpoint
1006          */
1007         core_tpg_deregister(se_tpg);
1008
1009         tl_tpg->tl_hba = NULL;
1010         tl_tpg->tl_tpgt = 0;
1011
1012         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
1013                  tcm_loop_dump_proto_id(tl_hba),
1014                  config_item_name(&wwn->wwn_group.cg_item), tpgt);
1015 }
1016
1017 /* End items for tcm_loop_naa_cit */
1018
1019 /* Start items for tcm_loop_cit */
1020
1021 static struct se_wwn *tcm_loop_make_scsi_hba(
1022         struct target_fabric_configfs *tf,
1023         struct config_group *group,
1024         const char *name)
1025 {
1026         struct tcm_loop_hba *tl_hba;
1027         struct Scsi_Host *sh;
1028         char *ptr;
1029         int ret, off = 0;
1030
1031         tl_hba = kzalloc(sizeof(*tl_hba), GFP_KERNEL);
1032         if (!tl_hba)
1033                 return ERR_PTR(-ENOMEM);
1034
1035         /*
1036          * Determine the emulated Protocol Identifier and Target Port Name
1037          * based on the incoming configfs directory name.
1038          */
1039         ptr = strstr(name, "naa.");
1040         if (ptr) {
1041                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1042                 goto check_len;
1043         }
1044         ptr = strstr(name, "fc.");
1045         if (ptr) {
1046                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1047                 off = 3; /* Skip over "fc." */
1048                 goto check_len;
1049         }
1050         ptr = strstr(name, "iqn.");
1051         if (!ptr) {
1052                 pr_err("Unable to locate prefix for emulated Target Port: %s\n",
1053                        name);
1054                 ret = -EINVAL;
1055                 goto out;
1056         }
1057         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1058
1059 check_len:
1060         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1061                 pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
1062                        name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN);
1063                 ret = -EINVAL;
1064                 goto out;
1065         }
1066         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1067
1068         /*
1069          * Call device_register(tl_hba->dev) to register the emulated
1070          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1071          * device_register() callbacks in tcm_loop_driver_probe()
1072          */
1073         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1074         if (ret)
1075                 goto out;
1076
1077         sh = tl_hba->sh;
1078         tcm_loop_hba_no_cnt++;
1079         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1080                  tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1081         return &tl_hba->tl_hba_wwn;
1082 out:
1083         kfree(tl_hba);
1084         return ERR_PTR(ret);
1085 }
1086
1087 static void tcm_loop_drop_scsi_hba(
1088         struct se_wwn *wwn)
1089 {
1090         struct tcm_loop_hba *tl_hba = container_of(wwn,
1091                                 struct tcm_loop_hba, tl_hba_wwn);
1092
1093         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1094                  tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1095                  tl_hba->sh->host_no);
1096         /*
1097          * Call device_unregister() on the original tl_hba->dev.
1098          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1099          * release *tl_hba;
1100          */
1101         device_unregister(&tl_hba->dev);
1102 }
1103
1104 /* Start items for tcm_loop_cit */
1105 static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1106 {
1107         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1108 }
1109
1110 CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1111
1112 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1113         &tcm_loop_wwn_attr_version,
1114         NULL,
1115 };
1116
1117 /* End items for tcm_loop_cit */
1118
1119 static const struct target_core_fabric_ops loop_ops = {
1120         .module                         = THIS_MODULE,
1121         .fabric_name                    = "loopback",
1122         .tpg_get_wwn                    = tcm_loop_get_endpoint_wwn,
1123         .tpg_get_tag                    = tcm_loop_get_tag,
1124         .tpg_check_demo_mode            = tcm_loop_check_demo_mode,
1125         .tpg_check_demo_mode_cache      = tcm_loop_check_demo_mode_cache,
1126         .tpg_check_demo_mode_write_protect =
1127                                 tcm_loop_check_demo_mode_write_protect,
1128         .tpg_check_prod_mode_write_protect =
1129                                 tcm_loop_check_prod_mode_write_protect,
1130         .tpg_check_prot_fabric_only     = tcm_loop_check_prot_fabric_only,
1131         .tpg_get_inst_index             = tcm_loop_get_inst_index,
1132         .check_stop_free                = tcm_loop_check_stop_free,
1133         .release_cmd                    = tcm_loop_release_cmd,
1134         .sess_get_index                 = tcm_loop_sess_get_index,
1135         .write_pending                  = tcm_loop_write_pending,
1136         .set_default_node_attributes    = tcm_loop_set_default_node_attributes,
1137         .get_cmd_state                  = tcm_loop_get_cmd_state,
1138         .queue_data_in                  = tcm_loop_queue_data_in,
1139         .queue_status                   = tcm_loop_queue_status,
1140         .queue_tm_rsp                   = tcm_loop_queue_tm_rsp,
1141         .aborted_task                   = tcm_loop_aborted_task,
1142         .fabric_make_wwn                = tcm_loop_make_scsi_hba,
1143         .fabric_drop_wwn                = tcm_loop_drop_scsi_hba,
1144         .fabric_make_tpg                = tcm_loop_make_naa_tpg,
1145         .fabric_drop_tpg                = tcm_loop_drop_naa_tpg,
1146         .fabric_post_link               = tcm_loop_port_link,
1147         .fabric_pre_unlink              = tcm_loop_port_unlink,
1148         .tfc_wwn_attrs                  = tcm_loop_wwn_attrs,
1149         .tfc_tpg_base_attrs             = tcm_loop_tpg_attrs,
1150         .tfc_tpg_attrib_attrs           = tcm_loop_tpg_attrib_attrs,
1151 };
1152
1153 static int __init tcm_loop_fabric_init(void)
1154 {
1155         int ret = -ENOMEM;
1156
1157         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1158         if (!tcm_loop_workqueue)
1159                 goto out;
1160
1161         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1162                                 sizeof(struct tcm_loop_cmd),
1163                                 __alignof__(struct tcm_loop_cmd),
1164                                 0, NULL);
1165         if (!tcm_loop_cmd_cache) {
1166                 pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n");
1167                 goto out_destroy_workqueue;
1168         }
1169
1170         ret = tcm_loop_alloc_core_bus();
1171         if (ret)
1172                 goto out_destroy_cache;
1173
1174         ret = target_register_template(&loop_ops);
1175         if (ret)
1176                 goto out_release_core_bus;
1177
1178         return 0;
1179
1180 out_release_core_bus:
1181         tcm_loop_release_core_bus();
1182 out_destroy_cache:
1183         kmem_cache_destroy(tcm_loop_cmd_cache);
1184 out_destroy_workqueue:
1185         destroy_workqueue(tcm_loop_workqueue);
1186 out:
1187         return ret;
1188 }
1189
1190 static void __exit tcm_loop_fabric_exit(void)
1191 {
1192         target_unregister_template(&loop_ops);
1193         tcm_loop_release_core_bus();
1194         kmem_cache_destroy(tcm_loop_cmd_cache);
1195         destroy_workqueue(tcm_loop_workqueue);
1196 }
1197
1198 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1199 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1200 MODULE_LICENSE("GPL");
1201 module_init(tcm_loop_fabric_init);
1202 module_exit(tcm_loop_fabric_exit);