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 #include <target/target_core_fabric_configfs.h>
  38 #include <target/target_core_configfs.h>
  39
  40 #include "tcm_loop.h"
  41
  42 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
  43
  44 /* Local pointer to allocated TCM configfs fabric module */
  45 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  46
  47 static struct workqueue_struct *tcm_loop_workqueue;
  48 static struct kmem_cache *tcm_loop_cmd_cache;
  49
  50 static int tcm_loop_hba_no_cnt;
  51
  52 static int tcm_loop_queue_status(struct se_cmd *se_cmd);
  53
  54 /*
  55  * Called from struct target_core_fabric_ops->check_stop_free()
  56  */
  57 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  58 {
  59         /*
  60          * Do not release struct se_cmd's containing a valid TMR
  61          * pointer.  These will be released directly in tcm_loop_device_reset()
  62          * with transport_generic_free_cmd().
  63          */
  64         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
  65                 return 0;
  66         /*
  67          * Release the struct se_cmd, which will make a callback to release
  68          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
  69          */
  70         transport_generic_free_cmd(se_cmd, 0);
  71         return 1;
  72 }
  73
  74 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  75 {
  76         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  77                                 struct tcm_loop_cmd, tl_se_cmd);
  78
  79         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  80 }
  81
  82 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  83 {
  84         seq_printf(m, "tcm_loop_proc_info()\n");
  85         return 0;
  86 }
  87
  88 static int tcm_loop_driver_probe(struct device *);
  89 static int tcm_loop_driver_remove(struct device *);
  90
  91 static int pseudo_lld_bus_match(struct device *dev,
  92                                 struct device_driver *dev_driver)
  93 {
  94         return 1;
  95 }
  96
  97 static struct bus_type tcm_loop_lld_bus = {
  98         .name                   = "tcm_loop_bus",
  99         .match                  = pseudo_lld_bus_match,
 100         .probe                  = tcm_loop_driver_probe,
 101         .remove                 = tcm_loop_driver_remove,
 102 };
 103
 104 static struct device_driver tcm_loop_driverfs = {
 105         .name                   = "tcm_loop",
 106         .bus                    = &tcm_loop_lld_bus,
 107 };
 108 /*
 109  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 110  */
 111 struct device *tcm_loop_primary;
 112
 113 static void tcm_loop_submission_work(struct work_struct *work)
 114 {
 115         struct tcm_loop_cmd *tl_cmd =
 116                 container_of(work, struct tcm_loop_cmd, work);
 117         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 118         struct scsi_cmnd *sc = tl_cmd->sc;
 119         struct tcm_loop_nexus *tl_nexus;
 120         struct tcm_loop_hba *tl_hba;
 121         struct tcm_loop_tpg *tl_tpg;
 122         struct scatterlist *sgl_bidi = NULL;
 123         u32 sgl_bidi_count = 0, transfer_length;
 124         int rc;
 125
 126         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 127         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 128
 129         /*
 130          * Ensure that this tl_tpg reference from the incoming sc->device->id
 131          * has already been configured via tcm_loop_make_naa_tpg().
 132          */
 133         if (!tl_tpg->tl_hba) {
 134                 set_host_byte(sc, DID_NO_CONNECT);
 135                 goto out_done;
 136         }
 137         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 138                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 139                 goto out_done;
 140         }
 141         tl_nexus = tl_tpg->tl_nexus;
 142         if (!tl_nexus) {
 143                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
 144                                 " does not exist\n");
 145                 set_host_byte(sc, DID_ERROR);
 146                 goto out_done;
 147         }
 148         if (scsi_bidi_cmnd(sc)) {
 149                 struct scsi_data_buffer *sdb = scsi_in(sc);
 150
 151                 sgl_bidi = sdb->table.sgl;
 152                 sgl_bidi_count = sdb->table.nents;
 153                 se_cmd->se_cmd_flags |= SCF_BIDI;
 154
 155         }
 156
 157         transfer_length = scsi_transfer_length(sc);
 158         if (!scsi_prot_sg_count(sc) &&
 159             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 160                 se_cmd->prot_pto = true;
 161                 /*
 162                  * loopback transport doesn't support
 163                  * WRITE_GENERATE, READ_STRIP protection
 164                  * information operations, go ahead unprotected.
 165                  */
 166                 transfer_length = scsi_bufflen(sc);
 167         }
 168
 169         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 170                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 171                         transfer_length, MSG_SIMPLE_TAG,
 172                         sc->sc_data_direction, 0,
 173                         scsi_sglist(sc), scsi_sg_count(sc),
 174                         sgl_bidi, sgl_bidi_count,
 175                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 176         if (rc < 0) {
 177                 set_host_byte(sc, DID_NO_CONNECT);
 178                 goto out_done;
 179         }
 180         return;
 181
 182 out_done:
 183         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 184         sc->scsi_done(sc);
 185         return;
 186 }
 187
 188 /*
 189  * ->queuecommand can be and usually is called from interrupt context, so
 190  * defer the actual submission to a workqueue.
 191  */
 192 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 193 {
 194         struct tcm_loop_cmd *tl_cmd;
 195
 196         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
 197                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 198                 sc->device->id, sc->device->channel, sc->device->lun,
 199                 sc->cmnd[0], scsi_bufflen(sc));
 200
 201         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 202         if (!tl_cmd) {
 203                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
 204                 set_host_byte(sc, DID_ERROR);
 205                 sc->scsi_done(sc);
 206                 return 0;
 207         }
 208
 209         tl_cmd->sc = sc;
 210         tl_cmd->sc_cmd_tag = sc->request->tag;
 211         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 212         queue_work(tcm_loop_workqueue, &tl_cmd->work);
 213         return 0;
 214 }
 215
 216 /*
 217  * Called from SCSI EH process context to issue a LUN_RESET TMR
 218  * to struct scsi_device
 219  */
 220 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 221                               int lun, int task, enum tcm_tmreq_table tmr)
 222 {
 223         struct se_cmd *se_cmd = NULL;
 224         struct se_session *se_sess;
 225         struct se_portal_group *se_tpg;
 226         struct tcm_loop_nexus *tl_nexus;
 227         struct tcm_loop_cmd *tl_cmd = NULL;
 228         struct tcm_loop_tmr *tl_tmr = NULL;
 229         int ret = TMR_FUNCTION_FAILED, rc;
 230
 231         /*
 232          * Locate the tl_nexus and se_sess pointers
 233          */
 234         tl_nexus = tl_tpg->tl_nexus;
 235         if (!tl_nexus) {
 236                 pr_err("Unable to perform device reset without"
 237                                 " active I_T Nexus\n");
 238                 return ret;
 239         }
 240
 241         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 242         if (!tl_cmd) {
 243                 pr_err("Unable to allocate memory for tl_cmd\n");
 244                 return ret;
 245         }
 246
 247         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 248         if (!tl_tmr) {
 249                 pr_err("Unable to allocate memory for tl_tmr\n");
 250                 goto release;
 251         }
 252         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 253
 254         se_cmd = &tl_cmd->tl_se_cmd;
 255         se_tpg = &tl_tpg->tl_se_tpg;
 256         se_sess = tl_tpg->tl_nexus->se_sess;
 257         /*
 258          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 259          */
 260         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 261                                 DMA_NONE, MSG_SIMPLE_TAG,
 262                                 &tl_cmd->tl_sense_buf[0]);
 263
 264         rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
 265         if (rc < 0)
 266                 goto release;
 267
 268         if (tmr == TMR_ABORT_TASK)
 269                 se_cmd->se_tmr_req->ref_task_tag = task;
 270
 271         /*
 272          * Locate the underlying TCM struct se_lun
 273          */
 274         if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
 275                 ret = TMR_LUN_DOES_NOT_EXIST;
 276                 goto release;
 277         }
 278         /*
 279          * Queue the TMR to TCM Core and sleep waiting for
 280          * tcm_loop_queue_tm_rsp() to wake us up.
 281          */
 282         transport_generic_handle_tmr(se_cmd);
 283         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 284         /*
 285          * The TMR LUN_RESET has completed, check the response status and
 286          * then release allocations.
 287          */
 288         ret = se_cmd->se_tmr_req->response;
 289 release:
 290         if (se_cmd)
 291                 transport_generic_free_cmd(se_cmd, 1);
 292         else
 293                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 294         kfree(tl_tmr);
 295         return ret;
 296 }
 297
 298 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 299 {
 300         struct tcm_loop_hba *tl_hba;
 301         struct tcm_loop_tpg *tl_tpg;
 302         int ret = FAILED;
 303
 304         /*
 305          * Locate the tcm_loop_hba_t pointer
 306          */
 307         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 308         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 309         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 310                                  sc->request->tag, TMR_ABORT_TASK);
 311         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 312 }
 313
 314 /*
 315  * Called from SCSI EH process context to issue a LUN_RESET TMR
 316  * to struct scsi_device
 317  */
 318 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 319 {
 320         struct tcm_loop_hba *tl_hba;
 321         struct tcm_loop_tpg *tl_tpg;
 322         int ret = FAILED;
 323
 324         /*
 325          * Locate the tcm_loop_hba_t pointer
 326          */
 327         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 328         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 329
 330         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 331                                  0, TMR_LUN_RESET);
 332         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 333 }
 334
 335 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 336 {
 337         struct tcm_loop_hba *tl_hba;
 338         struct tcm_loop_tpg *tl_tpg;
 339
 340         /*
 341          * Locate the tcm_loop_hba_t pointer
 342          */
 343         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 344         if (!tl_hba) {
 345                 pr_err("Unable to perform device reset without"
 346                                 " active I_T Nexus\n");
 347                 return FAILED;
 348         }
 349         /*
 350          * Locate the tl_tpg pointer from TargetID in sc->device->id
 351          */
 352         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 353         if (tl_tpg) {
 354                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 355                 return SUCCESS;
 356         }
 357         return FAILED;
 358 }
 359
 360 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 361 {
 362         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 363         return 0;
 364 }
 365
 366 static struct scsi_host_template tcm_loop_driver_template = {
 367         .show_info              = tcm_loop_show_info,
 368         .proc_name              = "tcm_loopback",
 369         .name                   = "TCM_Loopback",
 370         .queuecommand           = tcm_loop_queuecommand,
 371         .change_queue_depth     = scsi_change_queue_depth,
 372         .change_queue_type      = scsi_change_queue_type,
 373         .eh_abort_handler = tcm_loop_abort_task,
 374         .eh_device_reset_handler = tcm_loop_device_reset,
 375         .eh_target_reset_handler = tcm_loop_target_reset,
 376         .can_queue              = 1024,
 377         .this_id                = -1,
 378         .sg_tablesize           = 256,
 379         .cmd_per_lun            = 1024,
 380         .max_sectors            = 0xFFFF,
 381         .use_clustering         = DISABLE_CLUSTERING,
 382         .slave_alloc            = tcm_loop_slave_alloc,
 383         .module                 = THIS_MODULE,
 384         .use_blk_tags           = 1,
 385         .track_queue_depth      = 1,
 386 };
 387
 388 static int tcm_loop_driver_probe(struct device *dev)
 389 {
 390         struct tcm_loop_hba *tl_hba;
 391         struct Scsi_Host *sh;
 392         int error, host_prot;
 393
 394         tl_hba = to_tcm_loop_hba(dev);
 395
 396         sh = scsi_host_alloc(&tcm_loop_driver_template,
 397                         sizeof(struct tcm_loop_hba));
 398         if (!sh) {
 399                 pr_err("Unable to allocate struct scsi_host\n");
 400                 return -ENODEV;
 401         }
 402         tl_hba->sh = sh;
 403
 404         /*
 405          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 406          */
 407         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 408         /*
 409          * Setup single ID, Channel and LUN for now..
 410          */
 411         sh->max_id = 2;
 412         sh->max_lun = 0;
 413         sh->max_channel = 0;
 414         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 415
 416         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 417                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 418                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 419
 420         scsi_host_set_prot(sh, host_prot);
 421         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 422
 423         error = scsi_add_host(sh, &tl_hba->dev);
 424         if (error) {
 425                 pr_err("%s: scsi_add_host failed\n", __func__);
 426                 scsi_host_put(sh);
 427                 return -ENODEV;
 428         }
 429         return 0;
 430 }
 431
 432 static int tcm_loop_driver_remove(struct device *dev)
 433 {
 434         struct tcm_loop_hba *tl_hba;
 435         struct Scsi_Host *sh;
 436
 437         tl_hba = to_tcm_loop_hba(dev);
 438         sh = tl_hba->sh;
 439
 440         scsi_remove_host(sh);
 441         scsi_host_put(sh);
 442         return 0;
 443 }
 444
 445 static void tcm_loop_release_adapter(struct device *dev)
 446 {
 447         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 448
 449         kfree(tl_hba);
 450 }
 451
 452 /*
 453  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 454  */
 455 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 456 {
 457         int ret;
 458
 459         tl_hba->dev.bus = &tcm_loop_lld_bus;
 460         tl_hba->dev.parent = tcm_loop_primary;
 461         tl_hba->dev.release = &tcm_loop_release_adapter;
 462         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 463
 464         ret = device_register(&tl_hba->dev);
 465         if (ret) {
 466                 pr_err("device_register() failed for"
 467                                 " tl_hba->dev: %d\n", ret);
 468                 return -ENODEV;
 469         }
 470
 471         return 0;
 472 }
 473
 474 /*
 475  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 476  * tcm_loop SCSI bus.
 477  */
 478 static int tcm_loop_alloc_core_bus(void)
 479 {
 480         int ret;
 481
 482         tcm_loop_primary = root_device_register("tcm_loop_0");
 483         if (IS_ERR(tcm_loop_primary)) {
 484                 pr_err("Unable to allocate tcm_loop_primary\n");
 485                 return PTR_ERR(tcm_loop_primary);
 486         }
 487
 488         ret = bus_register(&tcm_loop_lld_bus);
 489         if (ret) {
 490                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 491                 goto dev_unreg;
 492         }
 493
 494         ret = driver_register(&tcm_loop_driverfs);
 495         if (ret) {
 496                 pr_err("driver_register() failed for"
 497                                 "tcm_loop_driverfs\n");
 498                 goto bus_unreg;
 499         }
 500
 501         pr_debug("Initialized TCM Loop Core Bus\n");
 502         return ret;
 503
 504 bus_unreg:
 505         bus_unregister(&tcm_loop_lld_bus);
 506 dev_unreg:
 507         root_device_unregister(tcm_loop_primary);
 508         return ret;
 509 }
 510
 511 static void tcm_loop_release_core_bus(void)
 512 {
 513         driver_unregister(&tcm_loop_driverfs);
 514         bus_unregister(&tcm_loop_lld_bus);
 515         root_device_unregister(tcm_loop_primary);
 516
 517         pr_debug("Releasing TCM Loop Core BUS\n");
 518 }
 519
 520 static char *tcm_loop_get_fabric_name(void)
 521 {
 522         return "loopback";
 523 }
 524
 525 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 526 {
 527         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 528         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 529         /*
 530          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 531          * time based on the protocol dependent prefix of the passed configfs group.
 532          *
 533          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 534          * ProtocolID using target_core_fabric_lib.c symbols.
 535          */
 536         switch (tl_hba->tl_proto_id) {
 537         case SCSI_PROTOCOL_SAS:
 538                 return sas_get_fabric_proto_ident(se_tpg);
 539         case SCSI_PROTOCOL_FCP:
 540                 return fc_get_fabric_proto_ident(se_tpg);
 541         case SCSI_PROTOCOL_ISCSI:
 542                 return iscsi_get_fabric_proto_ident(se_tpg);
 543         default:
 544                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 545                         " SAS emulation\n", tl_hba->tl_proto_id);
 546                 break;
 547         }
 548
 549         return sas_get_fabric_proto_ident(se_tpg);
 550 }
 551
 552 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 553 {
 554         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 555         /*
 556          * Return the passed NAA identifier for the SAS Target Port
 557          */
 558         return &tl_tpg->tl_hba->tl_wwn_address[0];
 559 }
 560
 561 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 562 {
 563         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 564         /*
 565          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 566          * to represent the SCSI Target Port.
 567          */
 568         return tl_tpg->tl_tpgt;
 569 }
 570
 571 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 572 {
 573         return 1;
 574 }
 575
 576 static u32 tcm_loop_get_pr_transport_id(
 577         struct se_portal_group *se_tpg,
 578         struct se_node_acl *se_nacl,
 579         struct t10_pr_registration *pr_reg,
 580         int *format_code,
 581         unsigned char *buf)
 582 {
 583         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 584         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 585
 586         switch (tl_hba->tl_proto_id) {
 587         case SCSI_PROTOCOL_SAS:
 588                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 589                                         format_code, buf);
 590         case SCSI_PROTOCOL_FCP:
 591                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 592                                         format_code, buf);
 593         case SCSI_PROTOCOL_ISCSI:
 594                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 595                                         format_code, buf);
 596         default:
 597                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 598                         " SAS emulation\n", tl_hba->tl_proto_id);
 599                 break;
 600         }
 601
 602         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 603                         format_code, buf);
 604 }
 605
 606 static u32 tcm_loop_get_pr_transport_id_len(
 607         struct se_portal_group *se_tpg,
 608         struct se_node_acl *se_nacl,
 609         struct t10_pr_registration *pr_reg,
 610         int *format_code)
 611 {
 612         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 613         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 614
 615         switch (tl_hba->tl_proto_id) {
 616         case SCSI_PROTOCOL_SAS:
 617                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 618                                         format_code);
 619         case SCSI_PROTOCOL_FCP:
 620                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 621                                         format_code);
 622         case SCSI_PROTOCOL_ISCSI:
 623                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 624                                         format_code);
 625         default:
 626                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 627                         " SAS emulation\n", tl_hba->tl_proto_id);
 628                 break;
 629         }
 630
 631         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 632                         format_code);
 633 }
 634
 635 /*
 636  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 637  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 638  */
 639 static char *tcm_loop_parse_pr_out_transport_id(
 640         struct se_portal_group *se_tpg,
 641         const char *buf,
 642         u32 *out_tid_len,
 643         char **port_nexus_ptr)
 644 {
 645         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 646         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 647
 648         switch (tl_hba->tl_proto_id) {
 649         case SCSI_PROTOCOL_SAS:
 650                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 651                                         port_nexus_ptr);
 652         case SCSI_PROTOCOL_FCP:
 653                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 654                                         port_nexus_ptr);
 655         case SCSI_PROTOCOL_ISCSI:
 656                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 657                                         port_nexus_ptr);
 658         default:
 659                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 660                         " SAS emulation\n", tl_hba->tl_proto_id);
 661                 break;
 662         }
 663
 664         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 665                         port_nexus_ptr);
 666 }
 667
 668 /*
 669  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 670  * based upon the incoming fabric dependent SCSI Initiator Port
 671  */
 672 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 673 {
 674         return 1;
 675 }
 676
 677 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 678 {
 679         return 0;
 680 }
 681
 682 /*
 683  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 684  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 685  */
 686 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 687 {
 688         return 0;
 689 }
 690
 691 /*
 692  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 693  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 694  * It has been added here as a nop for target_fabric_tf_ops_check()
 695  */
 696 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 697 {
 698         return 0;
 699 }
 700
 701 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 702         struct se_portal_group *se_tpg)
 703 {
 704         struct tcm_loop_nacl *tl_nacl;
 705
 706         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 707         if (!tl_nacl) {
 708                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 709                 return NULL;
 710         }
 711
 712         return &tl_nacl->se_node_acl;
 713 }
 714
 715 static void tcm_loop_tpg_release_fabric_acl(
 716         struct se_portal_group *se_tpg,
 717         struct se_node_acl *se_nacl)
 718 {
 719         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 720                                 struct tcm_loop_nacl, se_node_acl);
 721
 722         kfree(tl_nacl);
 723 }
 724
 725 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 726 {
 727         return 1;
 728 }
 729
 730 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 731 {
 732         return 1;
 733 }
 734
 735 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 736 {
 737         return;
 738 }
 739
 740 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 741 {
 742         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 743                         struct tcm_loop_cmd, tl_se_cmd);
 744
 745         return tl_cmd->sc_cmd_tag;
 746 }
 747
 748 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 749 {
 750         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 751                         struct tcm_loop_cmd, tl_se_cmd);
 752
 753         return tl_cmd->sc_cmd_state;
 754 }
 755
 756 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 757 {
 758         return 0;
 759 }
 760
 761 static void tcm_loop_close_session(struct se_session *se_sess)
 762 {
 763         return;
 764 };
 765
 766 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 767 {
 768         /*
 769          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 770          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 771          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 772          * format with transport_generic_map_mem_to_cmd().
 773          *
 774          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 775          * object execution queue.
 776          */
 777         target_execute_cmd(se_cmd);
 778         return 0;
 779 }
 780
 781 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 782 {
 783         return 0;
 784 }
 785
 786 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 787 {
 788         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 789                                 struct tcm_loop_cmd, tl_se_cmd);
 790         struct scsi_cmnd *sc = tl_cmd->sc;
 791
 792         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 793                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 794
 795         sc->result = SAM_STAT_GOOD;
 796         set_host_byte(sc, DID_OK);
 797         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 798             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 799                 scsi_set_resid(sc, se_cmd->residual_count);
 800         sc->scsi_done(sc);
 801         return 0;
 802 }
 803
 804 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 805 {
 806         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 807                                 struct tcm_loop_cmd, tl_se_cmd);
 808         struct scsi_cmnd *sc = tl_cmd->sc;
 809
 810         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 811                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 812
 813         if (se_cmd->sense_buffer &&
 814            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 815             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 816
 817                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 818                                 SCSI_SENSE_BUFFERSIZE);
 819                 sc->result = SAM_STAT_CHECK_CONDITION;
 820                 set_driver_byte(sc, DRIVER_SENSE);
 821         } else
 822                 sc->result = se_cmd->scsi_status;
 823
 824         set_host_byte(sc, DID_OK);
 825         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 826             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 827                 scsi_set_resid(sc, se_cmd->residual_count);
 828         sc->scsi_done(sc);
 829         return 0;
 830 }
 831
 832 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 833 {
 834         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 835         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 836         /*
 837          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 838          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 839          */
 840         atomic_set(&tl_tmr->tmr_complete, 1);
 841         wake_up(&tl_tmr->tl_tmr_wait);
 842 }
 843
 844 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 845 {
 846         return;
 847 }
 848
 849 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 850 {
 851         switch (tl_hba->tl_proto_id) {
 852         case SCSI_PROTOCOL_SAS:
 853                 return "SAS";
 854         case SCSI_PROTOCOL_FCP:
 855                 return "FCP";
 856         case SCSI_PROTOCOL_ISCSI:
 857                 return "iSCSI";
 858         default:
 859                 break;
 860         }
 861
 862         return "Unknown";
 863 }
 864
 865 /* Start items for tcm_loop_port_cit */
 866
 867 static int tcm_loop_port_link(
 868         struct se_portal_group *se_tpg,
 869         struct se_lun *lun)
 870 {
 871         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 872                                 struct tcm_loop_tpg, tl_se_tpg);
 873         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 874
 875         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 876         /*
 877          * Add Linux/SCSI struct scsi_device by HCTL
 878          */
 879         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 880
 881         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 882         return 0;
 883 }
 884
 885 static void tcm_loop_port_unlink(
 886         struct se_portal_group *se_tpg,
 887         struct se_lun *se_lun)
 888 {
 889         struct scsi_device *sd;
 890         struct tcm_loop_hba *tl_hba;
 891         struct tcm_loop_tpg *tl_tpg;
 892
 893         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 894         tl_hba = tl_tpg->tl_hba;
 895
 896         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 897                                 se_lun->unpacked_lun);
 898         if (!sd) {
 899                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 900                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 901                 return;
 902         }
 903         /*
 904          * Remove Linux/SCSI struct scsi_device by HCTL
 905          */
 906         scsi_remove_device(sd);
 907         scsi_device_put(sd);
 908
 909         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 910
 911         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 912 }
 913
 914 /* End items for tcm_loop_port_cit */
 915
 916 /* Start items for tcm_loop_nexus_cit */
 917
 918 static int tcm_loop_make_nexus(
 919         struct tcm_loop_tpg *tl_tpg,
 920         const char *name)
 921 {
 922         struct se_portal_group *se_tpg;
 923         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 924         struct tcm_loop_nexus *tl_nexus;
 925         int ret = -ENOMEM;
 926
 927         if (tl_tpg->tl_nexus) {
 928                 pr_debug("tl_tpg->tl_nexus already exists\n");
 929                 return -EEXIST;
 930         }
 931         se_tpg = &tl_tpg->tl_se_tpg;
 932
 933         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 934         if (!tl_nexus) {
 935                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 936                 return -ENOMEM;
 937         }
 938         /*
 939          * Initialize the struct se_session pointer
 940          */
 941         tl_nexus->se_sess = transport_init_session(TARGET_PROT_ALL);
 942         if (IS_ERR(tl_nexus->se_sess)) {
 943                 ret = PTR_ERR(tl_nexus->se_sess);
 944                 goto out;
 945         }
 946         /*
 947          * Since we are running in 'demo mode' this call with generate a
 948          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
 949          * Initiator port name of the passed configfs group 'name'.
 950          */
 951         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 952                                 se_tpg, (unsigned char *)name);
 953         if (!tl_nexus->se_sess->se_node_acl) {
 954                 transport_free_session(tl_nexus->se_sess);
 955                 goto out;
 956         }
 957         /*
 958          * Now, register the SAS I_T Nexus as active with the call to
 959          * transport_register_session()
 960          */
 961         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
 962                         tl_nexus->se_sess, tl_nexus);
 963         tl_tpg->tl_nexus = tl_nexus;
 964         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 965                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 966                 name);
 967         return 0;
 968
 969 out:
 970         kfree(tl_nexus);
 971         return ret;
 972 }
 973
 974 static int tcm_loop_drop_nexus(
 975         struct tcm_loop_tpg *tpg)
 976 {
 977         struct se_session *se_sess;
 978         struct tcm_loop_nexus *tl_nexus;
 979
 980         tl_nexus = tpg->tl_nexus;
 981         if (!tl_nexus)
 982                 return -ENODEV;
 983
 984         se_sess = tl_nexus->se_sess;
 985         if (!se_sess)
 986                 return -ENODEV;
 987
 988         if (atomic_read(&tpg->tl_tpg_port_count)) {
 989                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
 990                         " active TPG port count: %d\n",
 991                         atomic_read(&tpg->tl_tpg_port_count));
 992                 return -EPERM;
 993         }
 994
 995         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
 996                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
 997                 tl_nexus->se_sess->se_node_acl->initiatorname);
 998         /*
 999          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1000          */
1001         transport_deregister_session(tl_nexus->se_sess);
1002         tpg->tl_nexus = NULL;
1003         kfree(tl_nexus);
1004         return 0;
1005 }
1006
1007 /* End items for tcm_loop_nexus_cit */
1008
1009 static ssize_t tcm_loop_tpg_show_nexus(
1010         struct se_portal_group *se_tpg,
1011         char *page)
1012 {
1013         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1014                         struct tcm_loop_tpg, tl_se_tpg);
1015         struct tcm_loop_nexus *tl_nexus;
1016         ssize_t ret;
1017
1018         tl_nexus = tl_tpg->tl_nexus;
1019         if (!tl_nexus)
1020                 return -ENODEV;
1021
1022         ret = snprintf(page, PAGE_SIZE, "%s\n",
1023                 tl_nexus->se_sess->se_node_acl->initiatorname);
1024
1025         return ret;
1026 }
1027
1028 static ssize_t tcm_loop_tpg_store_nexus(
1029         struct se_portal_group *se_tpg,
1030         const char *page,
1031         size_t count)
1032 {
1033         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1034                         struct tcm_loop_tpg, tl_se_tpg);
1035         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1036         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1037         int ret;
1038         /*
1039          * Shutdown the active I_T nexus if 'NULL' is passed..
1040          */
1041         if (!strncmp(page, "NULL", 4)) {
1042                 ret = tcm_loop_drop_nexus(tl_tpg);
1043                 return (!ret) ? count : ret;
1044         }
1045         /*
1046          * Otherwise make sure the passed virtual Initiator port WWN matches
1047          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1048          * tcm_loop_make_nexus()
1049          */
1050         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1051                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1052                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1053                 return -EINVAL;
1054         }
1055         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1056
1057         ptr = strstr(i_port, "naa.");
1058         if (ptr) {
1059                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1060                         pr_err("Passed SAS Initiator Port %s does not"
1061                                 " match target port protoid: %s\n", i_port,
1062                                 tcm_loop_dump_proto_id(tl_hba));
1063                         return -EINVAL;
1064                 }
1065                 port_ptr = &i_port[0];
1066                 goto check_newline;
1067         }
1068         ptr = strstr(i_port, "fc.");
1069         if (ptr) {
1070                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1071                         pr_err("Passed FCP Initiator Port %s does not"
1072                                 " match target port protoid: %s\n", i_port,
1073                                 tcm_loop_dump_proto_id(tl_hba));
1074                         return -EINVAL;
1075                 }
1076                 port_ptr = &i_port[3]; /* Skip over "fc." */
1077                 goto check_newline;
1078         }
1079         ptr = strstr(i_port, "iqn.");
1080         if (ptr) {
1081                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1082                         pr_err("Passed iSCSI Initiator Port %s does not"
1083                                 " match target port protoid: %s\n", i_port,
1084                                 tcm_loop_dump_proto_id(tl_hba));
1085                         return -EINVAL;
1086                 }
1087                 port_ptr = &i_port[0];
1088                 goto check_newline;
1089         }
1090         pr_err("Unable to locate prefix for emulated Initiator Port:"
1091                         " %s\n", i_port);
1092         return -EINVAL;
1093         /*
1094          * Clear any trailing newline for the NAA WWN
1095          */
1096 check_newline:
1097         if (i_port[strlen(i_port)-1] == '\n')
1098                 i_port[strlen(i_port)-1] = '\0';
1099
1100         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1101         if (ret < 0)
1102                 return ret;
1103
1104         return count;
1105 }
1106
1107 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1108
1109 static ssize_t tcm_loop_tpg_show_transport_status(
1110         struct se_portal_group *se_tpg,
1111         char *page)
1112 {
1113         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1114                         struct tcm_loop_tpg, tl_se_tpg);
1115         const char *status = NULL;
1116         ssize_t ret = -EINVAL;
1117
1118         switch (tl_tpg->tl_transport_status) {
1119         case TCM_TRANSPORT_ONLINE:
1120                 status = "online";
1121                 break;
1122         case TCM_TRANSPORT_OFFLINE:
1123                 status = "offline";
1124                 break;
1125         default:
1126                 break;
1127         }
1128
1129         if (status)
1130                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1131
1132         return ret;
1133 }
1134
1135 static ssize_t tcm_loop_tpg_store_transport_status(
1136         struct se_portal_group *se_tpg,
1137         const char *page,
1138         size_t count)
1139 {
1140         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1141                         struct tcm_loop_tpg, tl_se_tpg);
1142
1143         if (!strncmp(page, "online", 6)) {
1144                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1145                 return count;
1146         }
1147         if (!strncmp(page, "offline", 7)) {
1148                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1149                 return count;
1150         }
1151         return -EINVAL;
1152 }
1153
1154 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1155
1156 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1157         &tcm_loop_tpg_nexus.attr,
1158         &tcm_loop_tpg_transport_status.attr,
1159         NULL,
1160 };
1161
1162 /* Start items for tcm_loop_naa_cit */
1163
1164 static struct se_portal_group *tcm_loop_make_naa_tpg(
1165         struct se_wwn *wwn,
1166         struct config_group *group,
1167         const char *name)
1168 {
1169         struct tcm_loop_hba *tl_hba = container_of(wwn,
1170                         struct tcm_loop_hba, tl_hba_wwn);
1171         struct tcm_loop_tpg *tl_tpg;
1172         char *tpgt_str, *end_ptr;
1173         int ret;
1174         unsigned short int tpgt;
1175
1176         tpgt_str = strstr(name, "tpgt_");
1177         if (!tpgt_str) {
1178                 pr_err("Unable to locate \"tpgt_#\" directory"
1179                                 " group\n");
1180                 return ERR_PTR(-EINVAL);
1181         }
1182         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1183         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1184
1185         if (tpgt >= TL_TPGS_PER_HBA) {
1186                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1187                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1188                 return ERR_PTR(-EINVAL);
1189         }
1190         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1191         tl_tpg->tl_hba = tl_hba;
1192         tl_tpg->tl_tpgt = tpgt;
1193         /*
1194          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1195          */
1196         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1197                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1198                         TRANSPORT_TPG_TYPE_NORMAL);
1199         if (ret < 0)
1200                 return ERR_PTR(-ENOMEM);
1201
1202         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1203                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1204                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1205
1206         return &tl_tpg->tl_se_tpg;
1207 }
1208
1209 static void tcm_loop_drop_naa_tpg(
1210         struct se_portal_group *se_tpg)
1211 {
1212         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1213         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1214                                 struct tcm_loop_tpg, tl_se_tpg);
1215         struct tcm_loop_hba *tl_hba;
1216         unsigned short tpgt;
1217
1218         tl_hba = tl_tpg->tl_hba;
1219         tpgt = tl_tpg->tl_tpgt;
1220         /*
1221          * Release the I_T Nexus for the Virtual SAS link if present
1222          */
1223         tcm_loop_drop_nexus(tl_tpg);
1224         /*
1225          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1226          */
1227         core_tpg_deregister(se_tpg);
1228
1229         tl_tpg->tl_hba = NULL;
1230         tl_tpg->tl_tpgt = 0;
1231
1232         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1233                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1234                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1235 }
1236
1237 /* End items for tcm_loop_naa_cit */
1238
1239 /* Start items for tcm_loop_cit */
1240
1241 static struct se_wwn *tcm_loop_make_scsi_hba(
1242         struct target_fabric_configfs *tf,
1243         struct config_group *group,
1244         const char *name)
1245 {
1246         struct tcm_loop_hba *tl_hba;
1247         struct Scsi_Host *sh;
1248         char *ptr;
1249         int ret, off = 0;
1250
1251         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1252         if (!tl_hba) {
1253                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1254                 return ERR_PTR(-ENOMEM);
1255         }
1256         /*
1257          * Determine the emulated Protocol Identifier and Target Port Name
1258          * based on the incoming configfs directory name.
1259          */
1260         ptr = strstr(name, "naa.");
1261         if (ptr) {
1262                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1263                 goto check_len;
1264         }
1265         ptr = strstr(name, "fc.");
1266         if (ptr) {
1267                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1268                 off = 3; /* Skip over "fc." */
1269                 goto check_len;
1270         }
1271         ptr = strstr(name, "iqn.");
1272         if (!ptr) {
1273                 pr_err("Unable to locate prefix for emulated Target "
1274                                 "Port: %s\n", name);
1275                 ret = -EINVAL;
1276                 goto out;
1277         }
1278         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1279
1280 check_len:
1281         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1282                 pr_err("Emulated NAA %s Address: %s, exceeds"
1283                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1284                         TL_WWN_ADDR_LEN);
1285                 ret = -EINVAL;
1286                 goto out;
1287         }
1288         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1289
1290         /*
1291          * Call device_register(tl_hba->dev) to register the emulated
1292          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1293          * device_register() callbacks in tcm_loop_driver_probe()
1294          */
1295         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1296         if (ret)
1297                 goto out;
1298
1299         sh = tl_hba->sh;
1300         tcm_loop_hba_no_cnt++;
1301         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1302                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1303                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1304
1305         return &tl_hba->tl_hba_wwn;
1306 out:
1307         kfree(tl_hba);
1308         return ERR_PTR(ret);
1309 }
1310
1311 static void tcm_loop_drop_scsi_hba(
1312         struct se_wwn *wwn)
1313 {
1314         struct tcm_loop_hba *tl_hba = container_of(wwn,
1315                                 struct tcm_loop_hba, tl_hba_wwn);
1316
1317         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1318                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1319                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1320         /*
1321          * Call device_unregister() on the original tl_hba->dev.
1322          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1323          * release *tl_hba;
1324          */
1325         device_unregister(&tl_hba->dev);
1326 }
1327
1328 /* Start items for tcm_loop_cit */
1329 static ssize_t tcm_loop_wwn_show_attr_version(
1330         struct target_fabric_configfs *tf,
1331         char *page)
1332 {
1333         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1334 }
1335
1336 TF_WWN_ATTR_RO(tcm_loop, version);
1337
1338 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1339         &tcm_loop_wwn_version.attr,
1340         NULL,
1341 };
1342
1343 /* End items for tcm_loop_cit */
1344
1345 static int tcm_loop_register_configfs(void)
1346 {
1347         struct target_fabric_configfs *fabric;
1348         int ret;
1349         /*
1350          * Set the TCM Loop HBA counter to zero
1351          */
1352         tcm_loop_hba_no_cnt = 0;
1353         /*
1354          * Register the top level struct config_item_type with TCM core
1355          */
1356         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1357         if (IS_ERR(fabric)) {
1358                 pr_err("tcm_loop_register_configfs() failed!\n");
1359                 return PTR_ERR(fabric);
1360         }
1361         /*
1362          * Setup the fabric API of function pointers used by target_core_mod
1363          */
1364         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1365         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1366         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1367         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1368         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1369         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1370         fabric->tf_ops.tpg_get_pr_transport_id_len =
1371                                         &tcm_loop_get_pr_transport_id_len;
1372         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1373                                         &tcm_loop_parse_pr_out_transport_id;
1374         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1375         fabric->tf_ops.tpg_check_demo_mode_cache =
1376                                         &tcm_loop_check_demo_mode_cache;
1377         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1378                                         &tcm_loop_check_demo_mode_write_protect;
1379         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1380                                         &tcm_loop_check_prod_mode_write_protect;
1381         /*
1382          * The TCM loopback fabric module runs in demo-mode to a local
1383          * virtual SCSI device, so fabric dependent initator ACLs are
1384          * not required.
1385          */
1386         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1387         fabric->tf_ops.tpg_release_fabric_acl =
1388                                         &tcm_loop_tpg_release_fabric_acl;
1389         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1390         /*
1391          * Used for setting up remaining TCM resources in process context
1392          */
1393         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1394         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1395         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1396         fabric->tf_ops.close_session = &tcm_loop_close_session;
1397         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1398         fabric->tf_ops.sess_get_initiator_sid = NULL;
1399         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1400         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1401         /*
1402          * Not used for TCM loopback
1403          */
1404         fabric->tf_ops.set_default_node_attributes =
1405                                         &tcm_loop_set_default_node_attributes;
1406         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1407         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1408         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1409         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1410         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1411         fabric->tf_ops.aborted_task = &tcm_loop_aborted_task;
1412
1413         /*
1414          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1415          */
1416         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1417         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1418         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1419         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1420         /*
1421          * fabric_post_link() and fabric_pre_unlink() are used for
1422          * registration and release of TCM Loop Virtual SCSI LUNs.
1423          */
1424         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1425         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1426         fabric->tf_ops.fabric_make_np = NULL;
1427         fabric->tf_ops.fabric_drop_np = NULL;
1428         /*
1429          * Setup default attribute lists for various fabric->tf_cit_tmpl
1430          */
1431         fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1432         fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1433         fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
1434         fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
1435         fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
1436         /*
1437          * Once fabric->tf_ops has been setup, now register the fabric for
1438          * use within TCM
1439          */
1440         ret = target_fabric_configfs_register(fabric);
1441         if (ret < 0) {
1442                 pr_err("target_fabric_configfs_register() for"
1443                                 " TCM_Loop failed!\n");
1444                 target_fabric_configfs_free(fabric);
1445                 return -1;
1446         }
1447         /*
1448          * Setup our local pointer to *fabric.
1449          */
1450         tcm_loop_fabric_configfs = fabric;
1451         pr_debug("TCM_LOOP[0] - Set fabric ->"
1452                         " tcm_loop_fabric_configfs\n");
1453         return 0;
1454 }
1455
1456 static void tcm_loop_deregister_configfs(void)
1457 {
1458         if (!tcm_loop_fabric_configfs)
1459                 return;
1460
1461         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1462         tcm_loop_fabric_configfs = NULL;
1463         pr_debug("TCM_LOOP[0] - Cleared"
1464                                 " tcm_loop_fabric_configfs\n");
1465 }
1466
1467 static int __init tcm_loop_fabric_init(void)
1468 {
1469         int ret = -ENOMEM;
1470
1471         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1472         if (!tcm_loop_workqueue)
1473                 goto out;
1474
1475         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1476                                 sizeof(struct tcm_loop_cmd),
1477                                 __alignof__(struct tcm_loop_cmd),
1478                                 0, NULL);
1479         if (!tcm_loop_cmd_cache) {
1480                 pr_debug("kmem_cache_create() for"
1481                         " tcm_loop_cmd_cache failed\n");
1482                 goto out_destroy_workqueue;
1483         }
1484
1485         ret = tcm_loop_alloc_core_bus();
1486         if (ret)
1487                 goto out_destroy_cache;
1488
1489         ret = tcm_loop_register_configfs();
1490         if (ret)
1491                 goto out_release_core_bus;
1492
1493         return 0;
1494
1495 out_release_core_bus:
1496         tcm_loop_release_core_bus();
1497 out_destroy_cache:
1498         kmem_cache_destroy(tcm_loop_cmd_cache);
1499 out_destroy_workqueue:
1500         destroy_workqueue(tcm_loop_workqueue);
1501 out:
1502         return ret;
1503 }
1504
1505 static void __exit tcm_loop_fabric_exit(void)
1506 {
1507         tcm_loop_deregister_configfs();
1508         tcm_loop_release_core_bus();
1509         kmem_cache_destroy(tcm_loop_cmd_cache);
1510         destroy_workqueue(tcm_loop_workqueue);
1511 }
1512
1513 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1514 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1515 MODULE_LICENSE("GPL");
1516 module_init(tcm_loop_fabric_init);
1517 module_exit(tcm_loop_fabric_exit);