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         /*
  55          * Do not release struct se_cmd's containing a valid TMR
  56          * pointer.  These will be released directly in tcm_loop_device_reset()
  57          * with transport_generic_free_cmd().
  58          */
  59         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
  60                 return 0;
  61         /*
  62          * Release the struct se_cmd, which will make a callback to release
  63          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
  64          */
  65         transport_generic_free_cmd(se_cmd, 0);
  66         return 1;
  67 }
  68
  69 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  70 {
  71         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  72                                 struct tcm_loop_cmd, tl_se_cmd);
  73
  74         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  75 }
  76
  77 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  78 {
  79         seq_printf(m, "tcm_loop_proc_info()\n");
  80         return 0;
  81 }
  82
  83 static int tcm_loop_driver_probe(struct device *);
  84 static int tcm_loop_driver_remove(struct device *);
  85
  86 static int pseudo_lld_bus_match(struct device *dev,
  87                                 struct device_driver *dev_driver)
  88 {
  89         return 1;
  90 }
  91
  92 static struct bus_type tcm_loop_lld_bus = {
  93         .name                   = "tcm_loop_bus",
  94         .match                  = pseudo_lld_bus_match,
  95         .probe                  = tcm_loop_driver_probe,
  96         .remove                 = tcm_loop_driver_remove,
  97 };
  98
  99 static struct device_driver tcm_loop_driverfs = {
 100         .name                   = "tcm_loop",
 101         .bus                    = &tcm_loop_lld_bus,
 102 };
 103 /*
 104  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 105  */
 106 static struct device *tcm_loop_primary;
 107
 108 static void tcm_loop_submission_work(struct work_struct *work)
 109 {
 110         struct tcm_loop_cmd *tl_cmd =
 111                 container_of(work, struct tcm_loop_cmd, work);
 112         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 113         struct scsi_cmnd *sc = tl_cmd->sc;
 114         struct tcm_loop_nexus *tl_nexus;
 115         struct tcm_loop_hba *tl_hba;
 116         struct tcm_loop_tpg *tl_tpg;
 117         struct scatterlist *sgl_bidi = NULL;
 118         u32 sgl_bidi_count = 0, transfer_length;
 119         int rc;
 120
 121         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 122         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 123
 124         /*
 125          * Ensure that this tl_tpg reference from the incoming sc->device->id
 126          * has already been configured via tcm_loop_make_naa_tpg().
 127          */
 128         if (!tl_tpg->tl_hba) {
 129                 set_host_byte(sc, DID_NO_CONNECT);
 130                 goto out_done;
 131         }
 132         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 133                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 134                 goto out_done;
 135         }
 136         tl_nexus = tl_tpg->tl_nexus;
 137         if (!tl_nexus) {
 138                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
 139                                 " does not exist\n");
 140                 set_host_byte(sc, DID_ERROR);
 141                 goto out_done;
 142         }
 143         if (scsi_bidi_cmnd(sc)) {
 144                 struct scsi_data_buffer *sdb = scsi_in(sc);
 145
 146                 sgl_bidi = sdb->table.sgl;
 147                 sgl_bidi_count = sdb->table.nents;
 148                 se_cmd->se_cmd_flags |= SCF_BIDI;
 149
 150         }
 151
 152         transfer_length = scsi_transfer_length(sc);
 153         if (!scsi_prot_sg_count(sc) &&
 154             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 155                 se_cmd->prot_pto = true;
 156                 /*
 157                  * loopback transport doesn't support
 158                  * WRITE_GENERATE, READ_STRIP protection
 159                  * information operations, go ahead unprotected.
 160                  */
 161                 transfer_length = scsi_bufflen(sc);
 162         }
 163
 164         se_cmd->tag = tl_cmd->sc_cmd_tag;
 165         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 166                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 167                         transfer_length, TCM_SIMPLE_TAG,
 168                         sc->sc_data_direction, 0,
 169                         scsi_sglist(sc), scsi_sg_count(sc),
 170                         sgl_bidi, sgl_bidi_count,
 171                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 172         if (rc < 0) {
 173                 set_host_byte(sc, DID_NO_CONNECT);
 174                 goto out_done;
 175         }
 176         return;
 177
 178 out_done:
 179         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 180         sc->scsi_done(sc);
 181         return;
 182 }
 183
 184 /*
 185  * ->queuecommand can be and usually is called from interrupt context, so
 186  * defer the actual submission to a workqueue.
 187  */
 188 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 189 {
 190         struct tcm_loop_cmd *tl_cmd;
 191
 192         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
 193                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 194                 sc->device->id, sc->device->channel, sc->device->lun,
 195                 sc->cmnd[0], scsi_bufflen(sc));
 196
 197         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 198         if (!tl_cmd) {
 199                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
 200                 set_host_byte(sc, DID_ERROR);
 201                 sc->scsi_done(sc);
 202                 return 0;
 203         }
 204
 205         tl_cmd->sc = sc;
 206         tl_cmd->sc_cmd_tag = sc->request->tag;
 207         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 208         queue_work(tcm_loop_workqueue, &tl_cmd->work);
 209         return 0;
 210 }
 211
 212 /*
 213  * Called from SCSI EH process context to issue a LUN_RESET TMR
 214  * to struct scsi_device
 215  */
 216 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 217                               u64 lun, int task, enum tcm_tmreq_table tmr)
 218 {
 219         struct se_cmd *se_cmd = NULL;
 220         struct se_session *se_sess;
 221         struct se_portal_group *se_tpg;
 222         struct tcm_loop_nexus *tl_nexus;
 223         struct tcm_loop_cmd *tl_cmd = NULL;
 224         struct tcm_loop_tmr *tl_tmr = NULL;
 225         int ret = TMR_FUNCTION_FAILED, rc;
 226
 227         /*
 228          * Locate the tl_nexus and se_sess pointers
 229          */
 230         tl_nexus = tl_tpg->tl_nexus;
 231         if (!tl_nexus) {
 232                 pr_err("Unable to perform device reset without"
 233                                 " active I_T Nexus\n");
 234                 return ret;
 235         }
 236
 237         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 238         if (!tl_cmd) {
 239                 pr_err("Unable to allocate memory for tl_cmd\n");
 240                 return ret;
 241         }
 242
 243         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 244         if (!tl_tmr) {
 245                 pr_err("Unable to allocate memory for tl_tmr\n");
 246                 goto release;
 247         }
 248         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 249
 250         se_cmd = &tl_cmd->tl_se_cmd;
 251         se_tpg = &tl_tpg->tl_se_tpg;
 252         se_sess = tl_tpg->tl_nexus->se_sess;
 253         /*
 254          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 255          */
 256         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 257                                 DMA_NONE, TCM_SIMPLE_TAG,
 258                                 &tl_cmd->tl_sense_buf[0]);
 259
 260         rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
 261         if (rc < 0)
 262                 goto release;
 263
 264         if (tmr == TMR_ABORT_TASK)
 265                 se_cmd->se_tmr_req->ref_task_tag = task;
 266
 267         /*
 268          * Locate the underlying TCM struct se_lun
 269          */
 270         if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
 271                 ret = TMR_LUN_DOES_NOT_EXIST;
 272                 goto release;
 273         }
 274         /*
 275          * Queue the TMR to TCM Core and sleep waiting for
 276          * tcm_loop_queue_tm_rsp() to wake us up.
 277          */
 278         transport_generic_handle_tmr(se_cmd);
 279         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 280         /*
 281          * The TMR LUN_RESET has completed, check the response status and
 282          * then release allocations.
 283          */
 284         ret = se_cmd->se_tmr_req->response;
 285 release:
 286         if (se_cmd)
 287                 transport_generic_free_cmd(se_cmd, 1);
 288         else
 289                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 290         kfree(tl_tmr);
 291         return ret;
 292 }
 293
 294 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 295 {
 296         struct tcm_loop_hba *tl_hba;
 297         struct tcm_loop_tpg *tl_tpg;
 298         int ret = FAILED;
 299
 300         /*
 301          * Locate the tcm_loop_hba_t pointer
 302          */
 303         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 304         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 305         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 306                                  sc->request->tag, TMR_ABORT_TASK);
 307         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 308 }
 309
 310 /*
 311  * Called from SCSI EH process context to issue a LUN_RESET TMR
 312  * to struct scsi_device
 313  */
 314 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 315 {
 316         struct tcm_loop_hba *tl_hba;
 317         struct tcm_loop_tpg *tl_tpg;
 318         int ret = FAILED;
 319
 320         /*
 321          * Locate the tcm_loop_hba_t pointer
 322          */
 323         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 324         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 325
 326         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 327                                  0, TMR_LUN_RESET);
 328         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 329 }
 330
 331 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 332 {
 333         struct tcm_loop_hba *tl_hba;
 334         struct tcm_loop_tpg *tl_tpg;
 335
 336         /*
 337          * Locate the tcm_loop_hba_t pointer
 338          */
 339         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 340         if (!tl_hba) {
 341                 pr_err("Unable to perform device reset without"
 342                                 " active I_T Nexus\n");
 343                 return FAILED;
 344         }
 345         /*
 346          * Locate the tl_tpg pointer from TargetID in sc->device->id
 347          */
 348         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 349         if (tl_tpg) {
 350                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 351                 return SUCCESS;
 352         }
 353         return FAILED;
 354 }
 355
 356 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 357 {
 358         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 359         return 0;
 360 }
 361
 362 static struct scsi_host_template tcm_loop_driver_template = {
 363         .show_info              = tcm_loop_show_info,
 364         .proc_name              = "tcm_loopback",
 365         .name                   = "TCM_Loopback",
 366         .queuecommand           = tcm_loop_queuecommand,
 367         .change_queue_depth     = scsi_change_queue_depth,
 368         .eh_abort_handler = tcm_loop_abort_task,
 369         .eh_device_reset_handler = tcm_loop_device_reset,
 370         .eh_target_reset_handler = tcm_loop_target_reset,
 371         .can_queue              = 1024,
 372         .this_id                = -1,
 373         .sg_tablesize           = 256,
 374         .cmd_per_lun            = 1024,
 375         .max_sectors            = 0xFFFF,
 376         .use_clustering         = DISABLE_CLUSTERING,
 377         .slave_alloc            = tcm_loop_slave_alloc,
 378         .module                 = THIS_MODULE,
 379         .track_queue_depth      = 1,
 380 };
 381
 382 static int tcm_loop_driver_probe(struct device *dev)
 383 {
 384         struct tcm_loop_hba *tl_hba;
 385         struct Scsi_Host *sh;
 386         int error, host_prot;
 387
 388         tl_hba = to_tcm_loop_hba(dev);
 389
 390         sh = scsi_host_alloc(&tcm_loop_driver_template,
 391                         sizeof(struct tcm_loop_hba));
 392         if (!sh) {
 393                 pr_err("Unable to allocate struct scsi_host\n");
 394                 return -ENODEV;
 395         }
 396         tl_hba->sh = sh;
 397
 398         /*
 399          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 400          */
 401         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 402         /*
 403          * Setup single ID, Channel and LUN for now..
 404          */
 405         sh->max_id = 2;
 406         sh->max_lun = 0;
 407         sh->max_channel = 0;
 408         sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 409
 410         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 411                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 412                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 413
 414         scsi_host_set_prot(sh, host_prot);
 415         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 416
 417         error = scsi_add_host(sh, &tl_hba->dev);
 418         if (error) {
 419                 pr_err("%s: scsi_add_host failed\n", __func__);
 420                 scsi_host_put(sh);
 421                 return -ENODEV;
 422         }
 423         return 0;
 424 }
 425
 426 static int tcm_loop_driver_remove(struct device *dev)
 427 {
 428         struct tcm_loop_hba *tl_hba;
 429         struct Scsi_Host *sh;
 430
 431         tl_hba = to_tcm_loop_hba(dev);
 432         sh = tl_hba->sh;
 433
 434         scsi_remove_host(sh);
 435         scsi_host_put(sh);
 436         return 0;
 437 }
 438
 439 static void tcm_loop_release_adapter(struct device *dev)
 440 {
 441         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 442
 443         kfree(tl_hba);
 444 }
 445
 446 /*
 447  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 448  */
 449 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 450 {
 451         int ret;
 452
 453         tl_hba->dev.bus = &tcm_loop_lld_bus;
 454         tl_hba->dev.parent = tcm_loop_primary;
 455         tl_hba->dev.release = &tcm_loop_release_adapter;
 456         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 457
 458         ret = device_register(&tl_hba->dev);
 459         if (ret) {
 460                 pr_err("device_register() failed for"
 461                                 " tl_hba->dev: %d\n", ret);
 462                 return -ENODEV;
 463         }
 464
 465         return 0;
 466 }
 467
 468 /*
 469  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 470  * tcm_loop SCSI bus.
 471  */
 472 static int tcm_loop_alloc_core_bus(void)
 473 {
 474         int ret;
 475
 476         tcm_loop_primary = root_device_register("tcm_loop_0");
 477         if (IS_ERR(tcm_loop_primary)) {
 478                 pr_err("Unable to allocate tcm_loop_primary\n");
 479                 return PTR_ERR(tcm_loop_primary);
 480         }
 481
 482         ret = bus_register(&tcm_loop_lld_bus);
 483         if (ret) {
 484                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 485                 goto dev_unreg;
 486         }
 487
 488         ret = driver_register(&tcm_loop_driverfs);
 489         if (ret) {
 490                 pr_err("driver_register() failed for"
 491                                 "tcm_loop_driverfs\n");
 492                 goto bus_unreg;
 493         }
 494
 495         pr_debug("Initialized TCM Loop Core Bus\n");
 496         return ret;
 497
 498 bus_unreg:
 499         bus_unregister(&tcm_loop_lld_bus);
 500 dev_unreg:
 501         root_device_unregister(tcm_loop_primary);
 502         return ret;
 503 }
 504
 505 static void tcm_loop_release_core_bus(void)
 506 {
 507         driver_unregister(&tcm_loop_driverfs);
 508         bus_unregister(&tcm_loop_lld_bus);
 509         root_device_unregister(tcm_loop_primary);
 510
 511         pr_debug("Releasing TCM Loop Core BUS\n");
 512 }
 513
 514 static char *tcm_loop_get_fabric_name(void)
 515 {
 516         return "loopback";
 517 }
 518
 519 static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
 520 {
 521         return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 522 }
 523
 524 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 525 {
 526         /*
 527          * Return the passed NAA identifier for the Target Port
 528          */
 529         return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
 530 }
 531
 532 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 533 {
 534         /*
 535          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 536          * to represent the SCSI Target Port.
 537          */
 538         return tl_tpg(se_tpg)->tl_tpgt;
 539 }
 540
 541 /*
 542  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 543  * based upon the incoming fabric dependent SCSI Initiator Port
 544  */
 545 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 546 {
 547         return 1;
 548 }
 549
 550 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 551 {
 552         return 0;
 553 }
 554
 555 /*
 556  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 557  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 558  */
 559 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 560 {
 561         return 0;
 562 }
 563
 564 /*
 565  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 566  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 567  * It has been added here as a nop for target_fabric_tf_ops_check()
 568  */
 569 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 570 {
 571         return 0;
 572 }
 573
 574 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
 575 {
 576         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 577                                                    tl_se_tpg);
 578         return tl_tpg->tl_fabric_prot_type;
 579 }
 580
 581 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 582 {
 583         return 1;
 584 }
 585
 586 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 587 {
 588         return 1;
 589 }
 590
 591 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 592 {
 593         return;
 594 }
 595
 596 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 597 {
 598         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 599                         struct tcm_loop_cmd, tl_se_cmd);
 600
 601         return tl_cmd->sc_cmd_state;
 602 }
 603
 604 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 605 {
 606         /*
 607          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 608          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 609          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 610          * format with transport_generic_map_mem_to_cmd().
 611          *
 612          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 613          * object execution queue.
 614          */
 615         target_execute_cmd(se_cmd);
 616         return 0;
 617 }
 618
 619 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 620 {
 621         return 0;
 622 }
 623
 624 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 625 {
 626         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 627                                 struct tcm_loop_cmd, tl_se_cmd);
 628         struct scsi_cmnd *sc = tl_cmd->sc;
 629
 630         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 631                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 632
 633         sc->result = SAM_STAT_GOOD;
 634         set_host_byte(sc, DID_OK);
 635         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 636             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 637                 scsi_set_resid(sc, se_cmd->residual_count);
 638         sc->scsi_done(sc);
 639         return 0;
 640 }
 641
 642 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 643 {
 644         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 645                                 struct tcm_loop_cmd, tl_se_cmd);
 646         struct scsi_cmnd *sc = tl_cmd->sc;
 647
 648         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 649                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 650
 651         if (se_cmd->sense_buffer &&
 652            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 653             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 654
 655                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 656                                 SCSI_SENSE_BUFFERSIZE);
 657                 sc->result = SAM_STAT_CHECK_CONDITION;
 658                 set_driver_byte(sc, DRIVER_SENSE);
 659         } else
 660                 sc->result = se_cmd->scsi_status;
 661
 662         set_host_byte(sc, DID_OK);
 663         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 664             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 665                 scsi_set_resid(sc, se_cmd->residual_count);
 666         sc->scsi_done(sc);
 667         return 0;
 668 }
 669
 670 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 671 {
 672         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 673         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 674         /*
 675          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 676          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 677          */
 678         atomic_set(&tl_tmr->tmr_complete, 1);
 679         wake_up(&tl_tmr->tl_tmr_wait);
 680 }
 681
 682 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 683 {
 684         return;
 685 }
 686
 687 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 688 {
 689         switch (tl_hba->tl_proto_id) {
 690         case SCSI_PROTOCOL_SAS:
 691                 return "SAS";
 692         case SCSI_PROTOCOL_FCP:
 693                 return "FCP";
 694         case SCSI_PROTOCOL_ISCSI:
 695                 return "iSCSI";
 696         default:
 697                 break;
 698         }
 699
 700         return "Unknown";
 701 }
 702
 703 /* Start items for tcm_loop_port_cit */
 704
 705 static int tcm_loop_port_link(
 706         struct se_portal_group *se_tpg,
 707         struct se_lun *lun)
 708 {
 709         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 710                                 struct tcm_loop_tpg, tl_se_tpg);
 711         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 712
 713         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 714         /*
 715          * Add Linux/SCSI struct scsi_device by HCTL
 716          */
 717         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 718
 719         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 720         return 0;
 721 }
 722
 723 static void tcm_loop_port_unlink(
 724         struct se_portal_group *se_tpg,
 725         struct se_lun *se_lun)
 726 {
 727         struct scsi_device *sd;
 728         struct tcm_loop_hba *tl_hba;
 729         struct tcm_loop_tpg *tl_tpg;
 730
 731         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 732         tl_hba = tl_tpg->tl_hba;
 733
 734         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 735                                 se_lun->unpacked_lun);
 736         if (!sd) {
 737                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 738                         "%llu\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 739                 return;
 740         }
 741         /*
 742          * Remove Linux/SCSI struct scsi_device by HCTL
 743          */
 744         scsi_remove_device(sd);
 745         scsi_device_put(sd);
 746
 747         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 748
 749         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 750 }
 751
 752 /* End items for tcm_loop_port_cit */
 753
 754 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
 755                 struct config_item *item, char *page)
 756 {
 757         struct se_portal_group *se_tpg = attrib_to_tpg(item);
 758         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 759                                                    tl_se_tpg);
 760
 761         return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
 762 }
 763
 764 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
 765                 struct config_item *item, const char *page, size_t count)
 766 {
 767         struct se_portal_group *se_tpg = attrib_to_tpg(item);
 768         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 769                                                    tl_se_tpg);
 770         unsigned long val;
 771         int ret = kstrtoul(page, 0, &val);
 772
 773         if (ret) {
 774                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
 775                 return ret;
 776         }
 777         if (val != 0 && val != 1 && val != 3) {
 778                 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
 779                 return -EINVAL;
 780         }
 781         tl_tpg->tl_fabric_prot_type = val;
 782
 783         return count;
 784 }
 785
 786 CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
 787
 788 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
 789         &tcm_loop_tpg_attrib_attr_fabric_prot_type,
 790         NULL,
 791 };
 792
 793 /* Start items for tcm_loop_nexus_cit */
 794
 795 static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
 796                                   struct se_session *se_sess, void *p)
 797 {
 798         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 799                                         struct tcm_loop_tpg, tl_se_tpg);
 800
 801         tl_tpg->tl_nexus = p;
 802         return 0;
 803 }
 804
 805 static int tcm_loop_make_nexus(
 806         struct tcm_loop_tpg *tl_tpg,
 807         const char *name)
 808 {
 809         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 810         struct tcm_loop_nexus *tl_nexus;
 811         int ret;
 812
 813         if (tl_tpg->tl_nexus) {
 814                 pr_debug("tl_tpg->tl_nexus already exists\n");
 815                 return -EEXIST;
 816         }
 817
 818         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 819         if (!tl_nexus) {
 820                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 821                 return -ENOMEM;
 822         }
 823
 824         tl_nexus->se_sess = target_alloc_session(&tl_tpg->tl_se_tpg, 0, 0,
 825                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
 826                                         name, tl_nexus, tcm_loop_alloc_sess_cb);
 827         if (IS_ERR(tl_nexus->se_sess)) {
 828                 ret = PTR_ERR(tl_nexus->se_sess);
 829                 kfree(tl_nexus);
 830                 return ret;
 831         }
 832
 833         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 834                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 835                 name);
 836         return 0;
 837 }
 838
 839 static int tcm_loop_drop_nexus(
 840         struct tcm_loop_tpg *tpg)
 841 {
 842         struct se_session *se_sess;
 843         struct tcm_loop_nexus *tl_nexus;
 844
 845         tl_nexus = tpg->tl_nexus;
 846         if (!tl_nexus)
 847                 return -ENODEV;
 848
 849         se_sess = tl_nexus->se_sess;
 850         if (!se_sess)
 851                 return -ENODEV;
 852
 853         if (atomic_read(&tpg->tl_tpg_port_count)) {
 854                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
 855                         " active TPG port count: %d\n",
 856                         atomic_read(&tpg->tl_tpg_port_count));
 857                 return -EPERM;
 858         }
 859
 860         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
 861                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
 862                 tl_nexus->se_sess->se_node_acl->initiatorname);
 863         /*
 864          * Release the SCSI I_T Nexus to the emulated Target Port
 865          */
 866         transport_deregister_session(tl_nexus->se_sess);
 867         tpg->tl_nexus = NULL;
 868         kfree(tl_nexus);
 869         return 0;
 870 }
 871
 872 /* End items for tcm_loop_nexus_cit */
 873
 874 static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
 875 {
 876         struct se_portal_group *se_tpg = to_tpg(item);
 877         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 878                         struct tcm_loop_tpg, tl_se_tpg);
 879         struct tcm_loop_nexus *tl_nexus;
 880         ssize_t ret;
 881
 882         tl_nexus = tl_tpg->tl_nexus;
 883         if (!tl_nexus)
 884                 return -ENODEV;
 885
 886         ret = snprintf(page, PAGE_SIZE, "%s\n",
 887                 tl_nexus->se_sess->se_node_acl->initiatorname);
 888
 889         return ret;
 890 }
 891
 892 static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
 893                 const char *page, size_t count)
 894 {
 895         struct se_portal_group *se_tpg = to_tpg(item);
 896         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 897                         struct tcm_loop_tpg, tl_se_tpg);
 898         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 899         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
 900         int ret;
 901         /*
 902          * Shutdown the active I_T nexus if 'NULL' is passed..
 903          */
 904         if (!strncmp(page, "NULL", 4)) {
 905                 ret = tcm_loop_drop_nexus(tl_tpg);
 906                 return (!ret) ? count : ret;
 907         }
 908         /*
 909          * Otherwise make sure the passed virtual Initiator port WWN matches
 910          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
 911          * tcm_loop_make_nexus()
 912          */
 913         if (strlen(page) >= TL_WWN_ADDR_LEN) {
 914                 pr_err("Emulated NAA Sas Address: %s, exceeds"
 915                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
 916                 return -EINVAL;
 917         }
 918         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
 919
 920         ptr = strstr(i_port, "naa.");
 921         if (ptr) {
 922                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
 923                         pr_err("Passed SAS Initiator Port %s does not"
 924                                 " match target port protoid: %s\n", i_port,
 925                                 tcm_loop_dump_proto_id(tl_hba));
 926                         return -EINVAL;
 927                 }
 928                 port_ptr = &i_port[0];
 929                 goto check_newline;
 930         }
 931         ptr = strstr(i_port, "fc.");
 932         if (ptr) {
 933                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
 934                         pr_err("Passed FCP Initiator Port %s does not"
 935                                 " match target port protoid: %s\n", i_port,
 936                                 tcm_loop_dump_proto_id(tl_hba));
 937                         return -EINVAL;
 938                 }
 939                 port_ptr = &i_port[3]; /* Skip over "fc." */
 940                 goto check_newline;
 941         }
 942         ptr = strstr(i_port, "iqn.");
 943         if (ptr) {
 944                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
 945                         pr_err("Passed iSCSI Initiator Port %s does not"
 946                                 " match target port protoid: %s\n", i_port,
 947                                 tcm_loop_dump_proto_id(tl_hba));
 948                         return -EINVAL;
 949                 }
 950                 port_ptr = &i_port[0];
 951                 goto check_newline;
 952         }
 953         pr_err("Unable to locate prefix for emulated Initiator Port:"
 954                         " %s\n", i_port);
 955         return -EINVAL;
 956         /*
 957          * Clear any trailing newline for the NAA WWN
 958          */
 959 check_newline:
 960         if (i_port[strlen(i_port)-1] == '\n')
 961                 i_port[strlen(i_port)-1] = '\0';
 962
 963         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
 964         if (ret < 0)
 965                 return ret;
 966
 967         return count;
 968 }
 969
 970 static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
 971                 char *page)
 972 {
 973         struct se_portal_group *se_tpg = to_tpg(item);
 974         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 975                         struct tcm_loop_tpg, tl_se_tpg);
 976         const char *status = NULL;
 977         ssize_t ret = -EINVAL;
 978
 979         switch (tl_tpg->tl_transport_status) {
 980         case TCM_TRANSPORT_ONLINE:
 981                 status = "online";
 982                 break;
 983         case TCM_TRANSPORT_OFFLINE:
 984                 status = "offline";
 985                 break;
 986         default:
 987                 break;
 988         }
 989
 990         if (status)
 991                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
 992
 993         return ret;
 994 }
 995
 996 static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
 997                 const char *page, size_t count)
 998 {
 999         struct se_portal_group *se_tpg = to_tpg(item);
1000         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1001                         struct tcm_loop_tpg, tl_se_tpg);
1002
1003         if (!strncmp(page, "online", 6)) {
1004                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1005                 return count;
1006         }
1007         if (!strncmp(page, "offline", 7)) {
1008                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1009                 if (tl_tpg->tl_nexus) {
1010                         struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
1011
1012                         core_allocate_nexus_loss_ua(tl_sess->se_node_acl);
1013                 }
1014                 return count;
1015         }
1016         return -EINVAL;
1017 }
1018
1019 static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
1020                                          char *page)
1021 {
1022         struct se_portal_group *se_tpg = to_tpg(item);
1023         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1024                         struct tcm_loop_tpg, tl_se_tpg);
1025         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1026
1027         return snprintf(page, PAGE_SIZE, "%d:0:%d\n",
1028                         tl_hba->sh->host_no, tl_tpg->tl_tpgt);
1029 }
1030
1031 CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
1032 CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
1033 CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
1034
1035 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1036         &tcm_loop_tpg_attr_nexus,
1037         &tcm_loop_tpg_attr_transport_status,
1038         &tcm_loop_tpg_attr_address,
1039         NULL,
1040 };
1041
1042 /* Start items for tcm_loop_naa_cit */
1043
1044 static struct se_portal_group *tcm_loop_make_naa_tpg(
1045         struct se_wwn *wwn,
1046         struct config_group *group,
1047         const char *name)
1048 {
1049         struct tcm_loop_hba *tl_hba = container_of(wwn,
1050                         struct tcm_loop_hba, tl_hba_wwn);
1051         struct tcm_loop_tpg *tl_tpg;
1052         int ret;
1053         unsigned long tpgt;
1054
1055         if (strstr(name, "tpgt_") != name) {
1056                 pr_err("Unable to locate \"tpgt_#\" directory"
1057                                 " group\n");
1058                 return ERR_PTR(-EINVAL);
1059         }
1060         if (kstrtoul(name+5, 10, &tpgt))
1061                 return ERR_PTR(-EINVAL);
1062
1063         if (tpgt >= TL_TPGS_PER_HBA) {
1064                 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA:"
1065                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1066                 return ERR_PTR(-EINVAL);
1067         }
1068         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1069         tl_tpg->tl_hba = tl_hba;
1070         tl_tpg->tl_tpgt = tpgt;
1071         /*
1072          * Register the tl_tpg as a emulated TCM Target Endpoint
1073          */
1074         ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
1075         if (ret < 0)
1076                 return ERR_PTR(-ENOMEM);
1077
1078         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1079                 " Target Port %s,t,0x%04lx\n", tcm_loop_dump_proto_id(tl_hba),
1080                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1081
1082         return &tl_tpg->tl_se_tpg;
1083 }
1084
1085 static void tcm_loop_drop_naa_tpg(
1086         struct se_portal_group *se_tpg)
1087 {
1088         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1089         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1090                                 struct tcm_loop_tpg, tl_se_tpg);
1091         struct tcm_loop_hba *tl_hba;
1092         unsigned short tpgt;
1093
1094         tl_hba = tl_tpg->tl_hba;
1095         tpgt = tl_tpg->tl_tpgt;
1096         /*
1097          * Release the I_T Nexus for the Virtual target link if present
1098          */
1099         tcm_loop_drop_nexus(tl_tpg);
1100         /*
1101          * Deregister the tl_tpg as a emulated TCM Target Endpoint
1102          */
1103         core_tpg_deregister(se_tpg);
1104
1105         tl_tpg->tl_hba = NULL;
1106         tl_tpg->tl_tpgt = 0;
1107
1108         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1109                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1110                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1111 }
1112
1113 /* End items for tcm_loop_naa_cit */
1114
1115 /* Start items for tcm_loop_cit */
1116
1117 static struct se_wwn *tcm_loop_make_scsi_hba(
1118         struct target_fabric_configfs *tf,
1119         struct config_group *group,
1120         const char *name)
1121 {
1122         struct tcm_loop_hba *tl_hba;
1123         struct Scsi_Host *sh;
1124         char *ptr;
1125         int ret, off = 0;
1126
1127         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1128         if (!tl_hba) {
1129                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1130                 return ERR_PTR(-ENOMEM);
1131         }
1132         /*
1133          * Determine the emulated Protocol Identifier and Target Port Name
1134          * based on the incoming configfs directory name.
1135          */
1136         ptr = strstr(name, "naa.");
1137         if (ptr) {
1138                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1139                 goto check_len;
1140         }
1141         ptr = strstr(name, "fc.");
1142         if (ptr) {
1143                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1144                 off = 3; /* Skip over "fc." */
1145                 goto check_len;
1146         }
1147         ptr = strstr(name, "iqn.");
1148         if (!ptr) {
1149                 pr_err("Unable to locate prefix for emulated Target "
1150                                 "Port: %s\n", name);
1151                 ret = -EINVAL;
1152                 goto out;
1153         }
1154         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1155
1156 check_len:
1157         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1158                 pr_err("Emulated NAA %s Address: %s, exceeds"
1159                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1160                         TL_WWN_ADDR_LEN);
1161                 ret = -EINVAL;
1162                 goto out;
1163         }
1164         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1165
1166         /*
1167          * Call device_register(tl_hba->dev) to register the emulated
1168          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1169          * device_register() callbacks in tcm_loop_driver_probe()
1170          */
1171         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1172         if (ret)
1173                 goto out;
1174
1175         sh = tl_hba->sh;
1176         tcm_loop_hba_no_cnt++;
1177         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1178                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1179                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1180
1181         return &tl_hba->tl_hba_wwn;
1182 out:
1183         kfree(tl_hba);
1184         return ERR_PTR(ret);
1185 }
1186
1187 static void tcm_loop_drop_scsi_hba(
1188         struct se_wwn *wwn)
1189 {
1190         struct tcm_loop_hba *tl_hba = container_of(wwn,
1191                                 struct tcm_loop_hba, tl_hba_wwn);
1192
1193         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1194                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1195                 tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1196                 tl_hba->sh->host_no);
1197         /*
1198          * Call device_unregister() on the original tl_hba->dev.
1199          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1200          * release *tl_hba;
1201          */
1202         device_unregister(&tl_hba->dev);
1203 }
1204
1205 /* Start items for tcm_loop_cit */
1206 static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1207 {
1208         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1209 }
1210
1211 CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1212
1213 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1214         &tcm_loop_wwn_attr_version,
1215         NULL,
1216 };
1217
1218 /* End items for tcm_loop_cit */
1219
1220 static const struct target_core_fabric_ops loop_ops = {
1221         .module                         = THIS_MODULE,
1222         .name                           = "loopback",
1223         .get_fabric_name                = tcm_loop_get_fabric_name,
1224         .tpg_get_wwn                    = tcm_loop_get_endpoint_wwn,
1225         .tpg_get_tag                    = tcm_loop_get_tag,
1226         .tpg_check_demo_mode            = tcm_loop_check_demo_mode,
1227         .tpg_check_demo_mode_cache      = tcm_loop_check_demo_mode_cache,
1228         .tpg_check_demo_mode_write_protect =
1229                                 tcm_loop_check_demo_mode_write_protect,
1230         .tpg_check_prod_mode_write_protect =
1231                                 tcm_loop_check_prod_mode_write_protect,
1232         .tpg_check_prot_fabric_only     = tcm_loop_check_prot_fabric_only,
1233         .tpg_get_inst_index             = tcm_loop_get_inst_index,
1234         .check_stop_free                = tcm_loop_check_stop_free,
1235         .release_cmd                    = tcm_loop_release_cmd,
1236         .sess_get_index                 = tcm_loop_sess_get_index,
1237         .write_pending                  = tcm_loop_write_pending,
1238         .write_pending_status           = tcm_loop_write_pending_status,
1239         .set_default_node_attributes    = tcm_loop_set_default_node_attributes,
1240         .get_cmd_state                  = tcm_loop_get_cmd_state,
1241         .queue_data_in                  = tcm_loop_queue_data_in,
1242         .queue_status                   = tcm_loop_queue_status,
1243         .queue_tm_rsp                   = tcm_loop_queue_tm_rsp,
1244         .aborted_task                   = tcm_loop_aborted_task,
1245         .fabric_make_wwn                = tcm_loop_make_scsi_hba,
1246         .fabric_drop_wwn                = tcm_loop_drop_scsi_hba,
1247         .fabric_make_tpg                = tcm_loop_make_naa_tpg,
1248         .fabric_drop_tpg                = tcm_loop_drop_naa_tpg,
1249         .fabric_post_link               = tcm_loop_port_link,
1250         .fabric_pre_unlink              = tcm_loop_port_unlink,
1251         .tfc_wwn_attrs                  = tcm_loop_wwn_attrs,
1252         .tfc_tpg_base_attrs             = tcm_loop_tpg_attrs,
1253         .tfc_tpg_attrib_attrs           = tcm_loop_tpg_attrib_attrs,
1254 };
1255
1256 static int __init tcm_loop_fabric_init(void)
1257 {
1258         int ret = -ENOMEM;
1259
1260         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1261         if (!tcm_loop_workqueue)
1262                 goto out;
1263
1264         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1265                                 sizeof(struct tcm_loop_cmd),
1266                                 __alignof__(struct tcm_loop_cmd),
1267                                 0, NULL);
1268         if (!tcm_loop_cmd_cache) {
1269                 pr_debug("kmem_cache_create() for"
1270                         " tcm_loop_cmd_cache failed\n");
1271                 goto out_destroy_workqueue;
1272         }
1273
1274         ret = tcm_loop_alloc_core_bus();
1275         if (ret)
1276                 goto out_destroy_cache;
1277
1278         ret = target_register_template(&loop_ops);
1279         if (ret)
1280                 goto out_release_core_bus;
1281
1282         return 0;
1283
1284 out_release_core_bus:
1285         tcm_loop_release_core_bus();
1286 out_destroy_cache:
1287         kmem_cache_destroy(tcm_loop_cmd_cache);
1288 out_destroy_workqueue:
1289         destroy_workqueue(tcm_loop_workqueue);
1290 out:
1291         return ret;
1292 }
1293
1294 static void __exit tcm_loop_fabric_exit(void)
1295 {
1296         target_unregister_template(&loop_ops);
1297         tcm_loop_release_core_bus();
1298         kmem_cache_destroy(tcm_loop_cmd_cache);
1299         destroy_workqueue(tcm_loop_workqueue);
1300 }
1301
1302 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1303 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1304 MODULE_LICENSE("GPL");
1305 module_init(tcm_loop_fabric_init);
1306 module_exit(tcm_loop_fabric_exit);