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 /*
 114  * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
 115  * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
 116  */
 117 static int tcm_loop_change_queue_depth(
 118         struct scsi_device *sdev,
 119         int depth,
 120         int reason)
 121 {
 122         scsi_adjust_queue_depth(sdev, depth);
 123         return sdev->queue_depth;
 124 }
 125
 126 static void tcm_loop_submission_work(struct work_struct *work)
 127 {
 128         struct tcm_loop_cmd *tl_cmd =
 129                 container_of(work, struct tcm_loop_cmd, work);
 130         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 131         struct scsi_cmnd *sc = tl_cmd->sc;
 132         struct tcm_loop_nexus *tl_nexus;
 133         struct tcm_loop_hba *tl_hba;
 134         struct tcm_loop_tpg *tl_tpg;
 135         struct scatterlist *sgl_bidi = NULL;
 136         u32 sgl_bidi_count = 0, transfer_length;
 137         int rc;
 138
 139         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 140         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 141
 142         /*
 143          * Ensure that this tl_tpg reference from the incoming sc->device->id
 144          * has already been configured via tcm_loop_make_naa_tpg().
 145          */
 146         if (!tl_tpg->tl_hba) {
 147                 set_host_byte(sc, DID_NO_CONNECT);
 148                 goto out_done;
 149         }
 150         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 151                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 152                 goto out_done;
 153         }
 154         tl_nexus = tl_hba->tl_nexus;
 155         if (!tl_nexus) {
 156                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
 157                                 " does not exist\n");
 158                 set_host_byte(sc, DID_ERROR);
 159                 goto out_done;
 160         }
 161         if (scsi_bidi_cmnd(sc)) {
 162                 struct scsi_data_buffer *sdb = scsi_in(sc);
 163
 164                 sgl_bidi = sdb->table.sgl;
 165                 sgl_bidi_count = sdb->table.nents;
 166                 se_cmd->se_cmd_flags |= SCF_BIDI;
 167
 168         }
 169
 170         transfer_length = scsi_transfer_length(sc);
 171         if (!scsi_prot_sg_count(sc) &&
 172             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 173                 se_cmd->prot_pto = true;
 174                 /*
 175                  * loopback transport doesn't support
 176                  * WRITE_GENERATE, READ_STRIP protection
 177                  * information operations, go ahead unprotected.
 178                  */
 179                 transfer_length = scsi_bufflen(sc);
 180         }
 181
 182         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 183                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 184                         transfer_length, MSG_SIMPLE_TAG,
 185                         sc->sc_data_direction, 0,
 186                         scsi_sglist(sc), scsi_sg_count(sc),
 187                         sgl_bidi, sgl_bidi_count,
 188                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 189         if (rc < 0) {
 190                 set_host_byte(sc, DID_NO_CONNECT);
 191                 goto out_done;
 192         }
 193         return;
 194
 195 out_done:
 196         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 197         sc->scsi_done(sc);
 198         return;
 199 }
 200
 201 /*
 202  * ->queuecommand can be and usually is called from interrupt context, so
 203  * defer the actual submission to a workqueue.
 204  */
 205 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 206 {
 207         struct tcm_loop_cmd *tl_cmd;
 208
 209         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
 210                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 211                 sc->device->id, sc->device->channel, sc->device->lun,
 212                 sc->cmnd[0], scsi_bufflen(sc));
 213
 214         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 215         if (!tl_cmd) {
 216                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
 217                 set_host_byte(sc, DID_ERROR);
 218                 sc->scsi_done(sc);
 219                 return 0;
 220         }
 221
 222         tl_cmd->sc = sc;
 223         tl_cmd->sc_cmd_tag = sc->request->tag;
 224         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 225         queue_work(tcm_loop_workqueue, &tl_cmd->work);
 226         return 0;
 227 }
 228
 229 /*
 230  * Called from SCSI EH process context to issue a LUN_RESET TMR
 231  * to struct scsi_device
 232  */
 233 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 234                               struct tcm_loop_nexus *tl_nexus,
 235                               int lun, int task, enum tcm_tmreq_table tmr)
 236 {
 237         struct se_cmd *se_cmd = NULL;
 238         struct se_session *se_sess;
 239         struct se_portal_group *se_tpg;
 240         struct tcm_loop_cmd *tl_cmd = NULL;
 241         struct tcm_loop_tmr *tl_tmr = NULL;
 242         int ret = TMR_FUNCTION_FAILED, rc;
 243
 244         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 245         if (!tl_cmd) {
 246                 pr_err("Unable to allocate memory for tl_cmd\n");
 247                 return ret;
 248         }
 249
 250         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 251         if (!tl_tmr) {
 252                 pr_err("Unable to allocate memory for tl_tmr\n");
 253                 goto release;
 254         }
 255         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 256
 257         se_cmd = &tl_cmd->tl_se_cmd;
 258         se_tpg = &tl_tpg->tl_se_tpg;
 259         se_sess = tl_nexus->se_sess;
 260         /*
 261          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 262          */
 263         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 264                                 DMA_NONE, MSG_SIMPLE_TAG,
 265                                 &tl_cmd->tl_sense_buf[0]);
 266
 267         rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
 268         if (rc < 0)
 269                 goto release;
 270
 271         if (tmr == TMR_ABORT_TASK)
 272                 se_cmd->se_tmr_req->ref_task_tag = task;
 273
 274         /*
 275          * Locate the underlying TCM struct se_lun
 276          */
 277         if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
 278                 ret = TMR_LUN_DOES_NOT_EXIST;
 279                 goto release;
 280         }
 281         /*
 282          * Queue the TMR to TCM Core and sleep waiting for
 283          * tcm_loop_queue_tm_rsp() to wake us up.
 284          */
 285         transport_generic_handle_tmr(se_cmd);
 286         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 287         /*
 288          * The TMR LUN_RESET has completed, check the response status and
 289          * then release allocations.
 290          */
 291         ret = se_cmd->se_tmr_req->response;
 292 release:
 293         if (se_cmd)
 294                 transport_generic_free_cmd(se_cmd, 1);
 295         else
 296                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 297         kfree(tl_tmr);
 298         return ret;
 299 }
 300
 301 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 302 {
 303         struct tcm_loop_hba *tl_hba;
 304         struct tcm_loop_nexus *tl_nexus;
 305         struct tcm_loop_tpg *tl_tpg;
 306         int ret = FAILED;
 307
 308         /*
 309          * Locate the tcm_loop_hba_t pointer
 310          */
 311         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 312         /*
 313          * Locate the tl_nexus and se_sess pointers
 314          */
 315         tl_nexus = tl_hba->tl_nexus;
 316         if (!tl_nexus) {
 317                 pr_err("Unable to perform device reset without"
 318                                 " active I_T Nexus\n");
 319                 return FAILED;
 320         }
 321
 322         /*
 323          * Locate the tl_tpg pointer from TargetID in sc->device->id
 324          */
 325         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 326         ret = tcm_loop_issue_tmr(tl_tpg, tl_nexus, sc->device->lun,
 327                                  sc->request->tag, TMR_ABORT_TASK);
 328         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 329 }
 330
 331 /*
 332  * Called from SCSI EH process context to issue a LUN_RESET TMR
 333  * to struct scsi_device
 334  */
 335 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 336 {
 337         struct tcm_loop_hba *tl_hba;
 338         struct tcm_loop_nexus *tl_nexus;
 339         struct tcm_loop_tpg *tl_tpg;
 340         int ret = FAILED;
 341
 342         /*
 343          * Locate the tcm_loop_hba_t pointer
 344          */
 345         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 346         /*
 347          * Locate the tl_nexus and se_sess pointers
 348          */
 349         tl_nexus = tl_hba->tl_nexus;
 350         if (!tl_nexus) {
 351                 pr_err("Unable to perform device reset without"
 352                                 " active I_T Nexus\n");
 353                 return FAILED;
 354         }
 355         /*
 356          * Locate the tl_tpg pointer from TargetID in sc->device->id
 357          */
 358         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 359         ret = tcm_loop_issue_tmr(tl_tpg, tl_nexus, sc->device->lun,
 360                                  0, TMR_LUN_RESET);
 361         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 362 }
 363
 364 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 365 {
 366         struct tcm_loop_hba *tl_hba;
 367         struct tcm_loop_tpg *tl_tpg;
 368
 369         /*
 370          * Locate the tcm_loop_hba_t pointer
 371          */
 372         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 373         if (!tl_hba) {
 374                 pr_err("Unable to perform device reset without"
 375                                 " active I_T Nexus\n");
 376                 return FAILED;
 377         }
 378         /*
 379          * Locate the tl_tpg pointer from TargetID in sc->device->id
 380          */
 381         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 382         if (tl_tpg) {
 383                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 384                 return SUCCESS;
 385         }
 386         return FAILED;
 387 }
 388
 389 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 390 {
 391         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 392         return 0;
 393 }
 394
 395 static struct scsi_host_template tcm_loop_driver_template = {
 396         .show_info              = tcm_loop_show_info,
 397         .proc_name              = "tcm_loopback",
 398         .name                   = "TCM_Loopback",
 399         .queuecommand           = tcm_loop_queuecommand,
 400         .change_queue_depth     = tcm_loop_change_queue_depth,
 401         .change_queue_type      = scsi_change_queue_type,
 402         .eh_abort_handler = tcm_loop_abort_task,
 403         .eh_device_reset_handler = tcm_loop_device_reset,
 404         .eh_target_reset_handler = tcm_loop_target_reset,
 405         .can_queue              = 1024,
 406         .this_id                = -1,
 407         .sg_tablesize           = 256,
 408         .cmd_per_lun            = 1024,
 409         .max_sectors            = 0xFFFF,
 410         .use_clustering         = DISABLE_CLUSTERING,
 411         .slave_alloc            = tcm_loop_slave_alloc,
 412         .module                 = THIS_MODULE,
 413         .use_blk_tags           = 1,
 414         .track_queue_depth      = 1,
 415 };
 416
 417 static int tcm_loop_driver_probe(struct device *dev)
 418 {
 419         struct tcm_loop_hba *tl_hba;
 420         struct Scsi_Host *sh;
 421         int error, host_prot;
 422
 423         tl_hba = to_tcm_loop_hba(dev);
 424
 425         sh = scsi_host_alloc(&tcm_loop_driver_template,
 426                         sizeof(struct tcm_loop_hba));
 427         if (!sh) {
 428                 pr_err("Unable to allocate struct scsi_host\n");
 429                 return -ENODEV;
 430         }
 431         tl_hba->sh = sh;
 432
 433         /*
 434          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 435          */
 436         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 437         /*
 438          * Setup single ID, Channel and LUN for now..
 439          */
 440         sh->max_id = 2;
 441         sh->max_lun = 0;
 442         sh->max_channel = 0;
 443         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 444
 445         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 446                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 447                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 448
 449         scsi_host_set_prot(sh, host_prot);
 450         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 451
 452         error = scsi_add_host(sh, &tl_hba->dev);
 453         if (error) {
 454                 pr_err("%s: scsi_add_host failed\n", __func__);
 455                 scsi_host_put(sh);
 456                 return -ENODEV;
 457         }
 458         return 0;
 459 }
 460
 461 static int tcm_loop_driver_remove(struct device *dev)
 462 {
 463         struct tcm_loop_hba *tl_hba;
 464         struct Scsi_Host *sh;
 465
 466         tl_hba = to_tcm_loop_hba(dev);
 467         sh = tl_hba->sh;
 468
 469         scsi_remove_host(sh);
 470         scsi_host_put(sh);
 471         return 0;
 472 }
 473
 474 static void tcm_loop_release_adapter(struct device *dev)
 475 {
 476         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 477
 478         kfree(tl_hba);
 479 }
 480
 481 /*
 482  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 483  */
 484 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 485 {
 486         int ret;
 487
 488         tl_hba->dev.bus = &tcm_loop_lld_bus;
 489         tl_hba->dev.parent = tcm_loop_primary;
 490         tl_hba->dev.release = &tcm_loop_release_adapter;
 491         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 492
 493         ret = device_register(&tl_hba->dev);
 494         if (ret) {
 495                 pr_err("device_register() failed for"
 496                                 " tl_hba->dev: %d\n", ret);
 497                 return -ENODEV;
 498         }
 499
 500         return 0;
 501 }
 502
 503 /*
 504  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 505  * tcm_loop SCSI bus.
 506  */
 507 static int tcm_loop_alloc_core_bus(void)
 508 {
 509         int ret;
 510
 511         tcm_loop_primary = root_device_register("tcm_loop_0");
 512         if (IS_ERR(tcm_loop_primary)) {
 513                 pr_err("Unable to allocate tcm_loop_primary\n");
 514                 return PTR_ERR(tcm_loop_primary);
 515         }
 516
 517         ret = bus_register(&tcm_loop_lld_bus);
 518         if (ret) {
 519                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 520                 goto dev_unreg;
 521         }
 522
 523         ret = driver_register(&tcm_loop_driverfs);
 524         if (ret) {
 525                 pr_err("driver_register() failed for"
 526                                 "tcm_loop_driverfs\n");
 527                 goto bus_unreg;
 528         }
 529
 530         pr_debug("Initialized TCM Loop Core Bus\n");
 531         return ret;
 532
 533 bus_unreg:
 534         bus_unregister(&tcm_loop_lld_bus);
 535 dev_unreg:
 536         root_device_unregister(tcm_loop_primary);
 537         return ret;
 538 }
 539
 540 static void tcm_loop_release_core_bus(void)
 541 {
 542         driver_unregister(&tcm_loop_driverfs);
 543         bus_unregister(&tcm_loop_lld_bus);
 544         root_device_unregister(tcm_loop_primary);
 545
 546         pr_debug("Releasing TCM Loop Core BUS\n");
 547 }
 548
 549 static char *tcm_loop_get_fabric_name(void)
 550 {
 551         return "loopback";
 552 }
 553
 554 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 555 {
 556         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 557         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 558         /*
 559          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 560          * time based on the protocol dependent prefix of the passed configfs group.
 561          *
 562          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 563          * ProtocolID using target_core_fabric_lib.c symbols.
 564          */
 565         switch (tl_hba->tl_proto_id) {
 566         case SCSI_PROTOCOL_SAS:
 567                 return sas_get_fabric_proto_ident(se_tpg);
 568         case SCSI_PROTOCOL_FCP:
 569                 return fc_get_fabric_proto_ident(se_tpg);
 570         case SCSI_PROTOCOL_ISCSI:
 571                 return iscsi_get_fabric_proto_ident(se_tpg);
 572         default:
 573                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 574                         " SAS emulation\n", tl_hba->tl_proto_id);
 575                 break;
 576         }
 577
 578         return sas_get_fabric_proto_ident(se_tpg);
 579 }
 580
 581 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 582 {
 583         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 584         /*
 585          * Return the passed NAA identifier for the SAS Target Port
 586          */
 587         return &tl_tpg->tl_hba->tl_wwn_address[0];
 588 }
 589
 590 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 591 {
 592         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 593         /*
 594          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 595          * to represent the SCSI Target Port.
 596          */
 597         return tl_tpg->tl_tpgt;
 598 }
 599
 600 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 601 {
 602         return 1;
 603 }
 604
 605 static u32 tcm_loop_get_pr_transport_id(
 606         struct se_portal_group *se_tpg,
 607         struct se_node_acl *se_nacl,
 608         struct t10_pr_registration *pr_reg,
 609         int *format_code,
 610         unsigned char *buf)
 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(se_tpg, se_nacl, pr_reg,
 618                                         format_code, buf);
 619         case SCSI_PROTOCOL_FCP:
 620                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 621                                         format_code, buf);
 622         case SCSI_PROTOCOL_ISCSI:
 623                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 624                                         format_code, buf);
 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(se_tpg, se_nacl, pr_reg,
 632                         format_code, buf);
 633 }
 634
 635 static u32 tcm_loop_get_pr_transport_id_len(
 636         struct se_portal_group *se_tpg,
 637         struct se_node_acl *se_nacl,
 638         struct t10_pr_registration *pr_reg,
 639         int *format_code)
 640 {
 641         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 642         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 643
 644         switch (tl_hba->tl_proto_id) {
 645         case SCSI_PROTOCOL_SAS:
 646                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 647                                         format_code);
 648         case SCSI_PROTOCOL_FCP:
 649                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 650                                         format_code);
 651         case SCSI_PROTOCOL_ISCSI:
 652                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 653                                         format_code);
 654         default:
 655                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 656                         " SAS emulation\n", tl_hba->tl_proto_id);
 657                 break;
 658         }
 659
 660         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 661                         format_code);
 662 }
 663
 664 /*
 665  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 666  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 667  */
 668 static char *tcm_loop_parse_pr_out_transport_id(
 669         struct se_portal_group *se_tpg,
 670         const char *buf,
 671         u32 *out_tid_len,
 672         char **port_nexus_ptr)
 673 {
 674         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 675         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 676
 677         switch (tl_hba->tl_proto_id) {
 678         case SCSI_PROTOCOL_SAS:
 679                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 680                                         port_nexus_ptr);
 681         case SCSI_PROTOCOL_FCP:
 682                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 683                                         port_nexus_ptr);
 684         case SCSI_PROTOCOL_ISCSI:
 685                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 686                                         port_nexus_ptr);
 687         default:
 688                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 689                         " SAS emulation\n", tl_hba->tl_proto_id);
 690                 break;
 691         }
 692
 693         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 694                         port_nexus_ptr);
 695 }
 696
 697 /*
 698  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 699  * based upon the incoming fabric dependent SCSI Initiator Port
 700  */
 701 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 702 {
 703         return 1;
 704 }
 705
 706 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 707 {
 708         return 0;
 709 }
 710
 711 /*
 712  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 713  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 714  */
 715 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 716 {
 717         return 0;
 718 }
 719
 720 /*
 721  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 722  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 723  * It has been added here as a nop for target_fabric_tf_ops_check()
 724  */
 725 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 726 {
 727         return 0;
 728 }
 729
 730 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 731         struct se_portal_group *se_tpg)
 732 {
 733         struct tcm_loop_nacl *tl_nacl;
 734
 735         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 736         if (!tl_nacl) {
 737                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 738                 return NULL;
 739         }
 740
 741         return &tl_nacl->se_node_acl;
 742 }
 743
 744 static void tcm_loop_tpg_release_fabric_acl(
 745         struct se_portal_group *se_tpg,
 746         struct se_node_acl *se_nacl)
 747 {
 748         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 749                                 struct tcm_loop_nacl, se_node_acl);
 750
 751         kfree(tl_nacl);
 752 }
 753
 754 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 755 {
 756         return 1;
 757 }
 758
 759 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 760 {
 761         return 1;
 762 }
 763
 764 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 765 {
 766         return;
 767 }
 768
 769 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 770 {
 771         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 772                         struct tcm_loop_cmd, tl_se_cmd);
 773
 774         return tl_cmd->sc_cmd_tag;
 775 }
 776
 777 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 778 {
 779         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 780                         struct tcm_loop_cmd, tl_se_cmd);
 781
 782         return tl_cmd->sc_cmd_state;
 783 }
 784
 785 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 786 {
 787         return 0;
 788 }
 789
 790 static void tcm_loop_close_session(struct se_session *se_sess)
 791 {
 792         return;
 793 };
 794
 795 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 796 {
 797         /*
 798          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 799          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 800          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 801          * format with transport_generic_map_mem_to_cmd().
 802          *
 803          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 804          * object execution queue.
 805          */
 806         target_execute_cmd(se_cmd);
 807         return 0;
 808 }
 809
 810 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 811 {
 812         return 0;
 813 }
 814
 815 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 816 {
 817         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 818                                 struct tcm_loop_cmd, tl_se_cmd);
 819         struct scsi_cmnd *sc = tl_cmd->sc;
 820
 821         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 822                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 823
 824         sc->result = SAM_STAT_GOOD;
 825         set_host_byte(sc, DID_OK);
 826         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 827             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 828                 scsi_set_resid(sc, se_cmd->residual_count);
 829         sc->scsi_done(sc);
 830         return 0;
 831 }
 832
 833 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 834 {
 835         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 836                                 struct tcm_loop_cmd, tl_se_cmd);
 837         struct scsi_cmnd *sc = tl_cmd->sc;
 838
 839         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 840                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 841
 842         if (se_cmd->sense_buffer &&
 843            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 844             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 845
 846                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 847                                 SCSI_SENSE_BUFFERSIZE);
 848                 sc->result = SAM_STAT_CHECK_CONDITION;
 849                 set_driver_byte(sc, DRIVER_SENSE);
 850         } else
 851                 sc->result = se_cmd->scsi_status;
 852
 853         set_host_byte(sc, DID_OK);
 854         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 855             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 856                 scsi_set_resid(sc, se_cmd->residual_count);
 857         sc->scsi_done(sc);
 858         return 0;
 859 }
 860
 861 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 862 {
 863         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 864         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 865         /*
 866          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 867          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 868          */
 869         atomic_set(&tl_tmr->tmr_complete, 1);
 870         wake_up(&tl_tmr->tl_tmr_wait);
 871 }
 872
 873 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 874 {
 875         return;
 876 }
 877
 878 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 879 {
 880         switch (tl_hba->tl_proto_id) {
 881         case SCSI_PROTOCOL_SAS:
 882                 return "SAS";
 883         case SCSI_PROTOCOL_FCP:
 884                 return "FCP";
 885         case SCSI_PROTOCOL_ISCSI:
 886                 return "iSCSI";
 887         default:
 888                 break;
 889         }
 890
 891         return "Unknown";
 892 }
 893
 894 /* Start items for tcm_loop_port_cit */
 895
 896 static int tcm_loop_port_link(
 897         struct se_portal_group *se_tpg,
 898         struct se_lun *lun)
 899 {
 900         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 901                                 struct tcm_loop_tpg, tl_se_tpg);
 902         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 903
 904         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 905         /*
 906          * Add Linux/SCSI struct scsi_device by HCTL
 907          */
 908         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 909
 910         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 911         return 0;
 912 }
 913
 914 static void tcm_loop_port_unlink(
 915         struct se_portal_group *se_tpg,
 916         struct se_lun *se_lun)
 917 {
 918         struct scsi_device *sd;
 919         struct tcm_loop_hba *tl_hba;
 920         struct tcm_loop_tpg *tl_tpg;
 921
 922         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 923         tl_hba = tl_tpg->tl_hba;
 924
 925         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 926                                 se_lun->unpacked_lun);
 927         if (!sd) {
 928                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 929                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 930                 return;
 931         }
 932         /*
 933          * Remove Linux/SCSI struct scsi_device by HCTL
 934          */
 935         scsi_remove_device(sd);
 936         scsi_device_put(sd);
 937
 938         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 939
 940         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 941 }
 942
 943 /* End items for tcm_loop_port_cit */
 944
 945 /* Start items for tcm_loop_nexus_cit */
 946
 947 static int tcm_loop_make_nexus(
 948         struct tcm_loop_tpg *tl_tpg,
 949         const char *name)
 950 {
 951         struct se_portal_group *se_tpg;
 952         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 953         struct tcm_loop_nexus *tl_nexus;
 954         int ret = -ENOMEM;
 955
 956         if (tl_tpg->tl_hba->tl_nexus) {
 957                 pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
 958                 return -EEXIST;
 959         }
 960         se_tpg = &tl_tpg->tl_se_tpg;
 961
 962         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 963         if (!tl_nexus) {
 964                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 965                 return -ENOMEM;
 966         }
 967         /*
 968          * Initialize the struct se_session pointer
 969          */
 970         tl_nexus->se_sess = transport_init_session(TARGET_PROT_ALL);
 971         if (IS_ERR(tl_nexus->se_sess)) {
 972                 ret = PTR_ERR(tl_nexus->se_sess);
 973                 goto out;
 974         }
 975         /*
 976          * Since we are running in 'demo mode' this call with generate a
 977          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
 978          * Initiator port name of the passed configfs group 'name'.
 979          */
 980         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 981                                 se_tpg, (unsigned char *)name);
 982         if (!tl_nexus->se_sess->se_node_acl) {
 983                 transport_free_session(tl_nexus->se_sess);
 984                 goto out;
 985         }
 986         /*
 987          * Now, register the SAS I_T Nexus as active with the call to
 988          * transport_register_session()
 989          */
 990         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
 991                         tl_nexus->se_sess, tl_nexus);
 992         tl_tpg->tl_hba->tl_nexus = tl_nexus;
 993         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 994                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 995                 name);
 996         return 0;
 997
 998 out:
 999         kfree(tl_nexus);
1000         return ret;
1001 }
1002
1003 static int tcm_loop_drop_nexus(
1004         struct tcm_loop_tpg *tpg)
1005 {
1006         struct se_session *se_sess;
1007         struct tcm_loop_nexus *tl_nexus;
1008         struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1009
1010         if (!tl_hba)
1011                 return -ENODEV;
1012
1013         tl_nexus = tl_hba->tl_nexus;
1014         if (!tl_nexus)
1015                 return -ENODEV;
1016
1017         se_sess = tl_nexus->se_sess;
1018         if (!se_sess)
1019                 return -ENODEV;
1020
1021         if (atomic_read(&tpg->tl_tpg_port_count)) {
1022                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
1023                         " active TPG port count: %d\n",
1024                         atomic_read(&tpg->tl_tpg_port_count));
1025                 return -EPERM;
1026         }
1027
1028         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1029                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1030                 tl_nexus->se_sess->se_node_acl->initiatorname);
1031         /*
1032          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1033          */
1034         transport_deregister_session(tl_nexus->se_sess);
1035         tpg->tl_hba->tl_nexus = NULL;
1036         kfree(tl_nexus);
1037         return 0;
1038 }
1039
1040 /* End items for tcm_loop_nexus_cit */
1041
1042 static ssize_t tcm_loop_tpg_show_nexus(
1043         struct se_portal_group *se_tpg,
1044         char *page)
1045 {
1046         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1047                         struct tcm_loop_tpg, tl_se_tpg);
1048         struct tcm_loop_nexus *tl_nexus;
1049         ssize_t ret;
1050
1051         tl_nexus = tl_tpg->tl_hba->tl_nexus;
1052         if (!tl_nexus)
1053                 return -ENODEV;
1054
1055         ret = snprintf(page, PAGE_SIZE, "%s\n",
1056                 tl_nexus->se_sess->se_node_acl->initiatorname);
1057
1058         return ret;
1059 }
1060
1061 static ssize_t tcm_loop_tpg_store_nexus(
1062         struct se_portal_group *se_tpg,
1063         const char *page,
1064         size_t count)
1065 {
1066         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1067                         struct tcm_loop_tpg, tl_se_tpg);
1068         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1069         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1070         int ret;
1071         /*
1072          * Shutdown the active I_T nexus if 'NULL' is passed..
1073          */
1074         if (!strncmp(page, "NULL", 4)) {
1075                 ret = tcm_loop_drop_nexus(tl_tpg);
1076                 return (!ret) ? count : ret;
1077         }
1078         /*
1079          * Otherwise make sure the passed virtual Initiator port WWN matches
1080          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1081          * tcm_loop_make_nexus()
1082          */
1083         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1084                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1085                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1086                 return -EINVAL;
1087         }
1088         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1089
1090         ptr = strstr(i_port, "naa.");
1091         if (ptr) {
1092                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1093                         pr_err("Passed SAS Initiator Port %s does not"
1094                                 " match target port protoid: %s\n", i_port,
1095                                 tcm_loop_dump_proto_id(tl_hba));
1096                         return -EINVAL;
1097                 }
1098                 port_ptr = &i_port[0];
1099                 goto check_newline;
1100         }
1101         ptr = strstr(i_port, "fc.");
1102         if (ptr) {
1103                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1104                         pr_err("Passed FCP Initiator Port %s does not"
1105                                 " match target port protoid: %s\n", i_port,
1106                                 tcm_loop_dump_proto_id(tl_hba));
1107                         return -EINVAL;
1108                 }
1109                 port_ptr = &i_port[3]; /* Skip over "fc." */
1110                 goto check_newline;
1111         }
1112         ptr = strstr(i_port, "iqn.");
1113         if (ptr) {
1114                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1115                         pr_err("Passed iSCSI Initiator Port %s does not"
1116                                 " match target port protoid: %s\n", i_port,
1117                                 tcm_loop_dump_proto_id(tl_hba));
1118                         return -EINVAL;
1119                 }
1120                 port_ptr = &i_port[0];
1121                 goto check_newline;
1122         }
1123         pr_err("Unable to locate prefix for emulated Initiator Port:"
1124                         " %s\n", i_port);
1125         return -EINVAL;
1126         /*
1127          * Clear any trailing newline for the NAA WWN
1128          */
1129 check_newline:
1130         if (i_port[strlen(i_port)-1] == '\n')
1131                 i_port[strlen(i_port)-1] = '\0';
1132
1133         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1134         if (ret < 0)
1135                 return ret;
1136
1137         return count;
1138 }
1139
1140 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1141
1142 static ssize_t tcm_loop_tpg_show_transport_status(
1143         struct se_portal_group *se_tpg,
1144         char *page)
1145 {
1146         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1147                         struct tcm_loop_tpg, tl_se_tpg);
1148         const char *status = NULL;
1149         ssize_t ret = -EINVAL;
1150
1151         switch (tl_tpg->tl_transport_status) {
1152         case TCM_TRANSPORT_ONLINE:
1153                 status = "online";
1154                 break;
1155         case TCM_TRANSPORT_OFFLINE:
1156                 status = "offline";
1157                 break;
1158         default:
1159                 break;
1160         }
1161
1162         if (status)
1163                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1164
1165         return ret;
1166 }
1167
1168 static ssize_t tcm_loop_tpg_store_transport_status(
1169         struct se_portal_group *se_tpg,
1170         const char *page,
1171         size_t count)
1172 {
1173         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1174                         struct tcm_loop_tpg, tl_se_tpg);
1175
1176         if (!strncmp(page, "online", 6)) {
1177                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1178                 return count;
1179         }
1180         if (!strncmp(page, "offline", 7)) {
1181                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1182                 return count;
1183         }
1184         return -EINVAL;
1185 }
1186
1187 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1188
1189 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1190         &tcm_loop_tpg_nexus.attr,
1191         &tcm_loop_tpg_transport_status.attr,
1192         NULL,
1193 };
1194
1195 /* Start items for tcm_loop_naa_cit */
1196
1197 static struct se_portal_group *tcm_loop_make_naa_tpg(
1198         struct se_wwn *wwn,
1199         struct config_group *group,
1200         const char *name)
1201 {
1202         struct tcm_loop_hba *tl_hba = container_of(wwn,
1203                         struct tcm_loop_hba, tl_hba_wwn);
1204         struct tcm_loop_tpg *tl_tpg;
1205         char *tpgt_str, *end_ptr;
1206         int ret;
1207         unsigned short int tpgt;
1208
1209         tpgt_str = strstr(name, "tpgt_");
1210         if (!tpgt_str) {
1211                 pr_err("Unable to locate \"tpgt_#\" directory"
1212                                 " group\n");
1213                 return ERR_PTR(-EINVAL);
1214         }
1215         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1216         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1217
1218         if (tpgt >= TL_TPGS_PER_HBA) {
1219                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1220                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1221                 return ERR_PTR(-EINVAL);
1222         }
1223         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1224         tl_tpg->tl_hba = tl_hba;
1225         tl_tpg->tl_tpgt = tpgt;
1226         /*
1227          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1228          */
1229         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1230                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1231                         TRANSPORT_TPG_TYPE_NORMAL);
1232         if (ret < 0)
1233                 return ERR_PTR(-ENOMEM);
1234
1235         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1236                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1237                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1238
1239         return &tl_tpg->tl_se_tpg;
1240 }
1241
1242 static void tcm_loop_drop_naa_tpg(
1243         struct se_portal_group *se_tpg)
1244 {
1245         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1246         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1247                                 struct tcm_loop_tpg, tl_se_tpg);
1248         struct tcm_loop_hba *tl_hba;
1249         unsigned short tpgt;
1250
1251         tl_hba = tl_tpg->tl_hba;
1252         tpgt = tl_tpg->tl_tpgt;
1253         /*
1254          * Release the I_T Nexus for the Virtual SAS link if present
1255          */
1256         tcm_loop_drop_nexus(tl_tpg);
1257         /*
1258          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1259          */
1260         core_tpg_deregister(se_tpg);
1261
1262         tl_tpg->tl_hba = NULL;
1263         tl_tpg->tl_tpgt = 0;
1264
1265         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1266                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1267                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1268 }
1269
1270 /* End items for tcm_loop_naa_cit */
1271
1272 /* Start items for tcm_loop_cit */
1273
1274 static struct se_wwn *tcm_loop_make_scsi_hba(
1275         struct target_fabric_configfs *tf,
1276         struct config_group *group,
1277         const char *name)
1278 {
1279         struct tcm_loop_hba *tl_hba;
1280         struct Scsi_Host *sh;
1281         char *ptr;
1282         int ret, off = 0;
1283
1284         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1285         if (!tl_hba) {
1286                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1287                 return ERR_PTR(-ENOMEM);
1288         }
1289         /*
1290          * Determine the emulated Protocol Identifier and Target Port Name
1291          * based on the incoming configfs directory name.
1292          */
1293         ptr = strstr(name, "naa.");
1294         if (ptr) {
1295                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1296                 goto check_len;
1297         }
1298         ptr = strstr(name, "fc.");
1299         if (ptr) {
1300                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1301                 off = 3; /* Skip over "fc." */
1302                 goto check_len;
1303         }
1304         ptr = strstr(name, "iqn.");
1305         if (!ptr) {
1306                 pr_err("Unable to locate prefix for emulated Target "
1307                                 "Port: %s\n", name);
1308                 ret = -EINVAL;
1309                 goto out;
1310         }
1311         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1312
1313 check_len:
1314         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1315                 pr_err("Emulated NAA %s Address: %s, exceeds"
1316                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1317                         TL_WWN_ADDR_LEN);
1318                 ret = -EINVAL;
1319                 goto out;
1320         }
1321         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1322
1323         /*
1324          * Call device_register(tl_hba->dev) to register the emulated
1325          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1326          * device_register() callbacks in tcm_loop_driver_probe()
1327          */
1328         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1329         if (ret)
1330                 goto out;
1331
1332         sh = tl_hba->sh;
1333         tcm_loop_hba_no_cnt++;
1334         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1335                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1336                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1337
1338         return &tl_hba->tl_hba_wwn;
1339 out:
1340         kfree(tl_hba);
1341         return ERR_PTR(ret);
1342 }
1343
1344 static void tcm_loop_drop_scsi_hba(
1345         struct se_wwn *wwn)
1346 {
1347         struct tcm_loop_hba *tl_hba = container_of(wwn,
1348                                 struct tcm_loop_hba, tl_hba_wwn);
1349
1350         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1351                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1352                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1353         /*
1354          * Call device_unregister() on the original tl_hba->dev.
1355          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1356          * release *tl_hba;
1357          */
1358         device_unregister(&tl_hba->dev);
1359 }
1360
1361 /* Start items for tcm_loop_cit */
1362 static ssize_t tcm_loop_wwn_show_attr_version(
1363         struct target_fabric_configfs *tf,
1364         char *page)
1365 {
1366         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1367 }
1368
1369 TF_WWN_ATTR_RO(tcm_loop, version);
1370
1371 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1372         &tcm_loop_wwn_version.attr,
1373         NULL,
1374 };
1375
1376 /* End items for tcm_loop_cit */
1377
1378 static int tcm_loop_register_configfs(void)
1379 {
1380         struct target_fabric_configfs *fabric;
1381         int ret;
1382         /*
1383          * Set the TCM Loop HBA counter to zero
1384          */
1385         tcm_loop_hba_no_cnt = 0;
1386         /*
1387          * Register the top level struct config_item_type with TCM core
1388          */
1389         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1390         if (IS_ERR(fabric)) {
1391                 pr_err("tcm_loop_register_configfs() failed!\n");
1392                 return PTR_ERR(fabric);
1393         }
1394         /*
1395          * Setup the fabric API of function pointers used by target_core_mod
1396          */
1397         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1398         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1399         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1400         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1401         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1402         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1403         fabric->tf_ops.tpg_get_pr_transport_id_len =
1404                                         &tcm_loop_get_pr_transport_id_len;
1405         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1406                                         &tcm_loop_parse_pr_out_transport_id;
1407         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1408         fabric->tf_ops.tpg_check_demo_mode_cache =
1409                                         &tcm_loop_check_demo_mode_cache;
1410         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1411                                         &tcm_loop_check_demo_mode_write_protect;
1412         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1413                                         &tcm_loop_check_prod_mode_write_protect;
1414         /*
1415          * The TCM loopback fabric module runs in demo-mode to a local
1416          * virtual SCSI device, so fabric dependent initator ACLs are
1417          * not required.
1418          */
1419         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1420         fabric->tf_ops.tpg_release_fabric_acl =
1421                                         &tcm_loop_tpg_release_fabric_acl;
1422         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1423         /*
1424          * Used for setting up remaining TCM resources in process context
1425          */
1426         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1427         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1428         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1429         fabric->tf_ops.close_session = &tcm_loop_close_session;
1430         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1431         fabric->tf_ops.sess_get_initiator_sid = NULL;
1432         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1433         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1434         /*
1435          * Not used for TCM loopback
1436          */
1437         fabric->tf_ops.set_default_node_attributes =
1438                                         &tcm_loop_set_default_node_attributes;
1439         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1440         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1441         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1442         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1443         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1444         fabric->tf_ops.aborted_task = &tcm_loop_aborted_task;
1445
1446         /*
1447          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1448          */
1449         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1450         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1451         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1452         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1453         /*
1454          * fabric_post_link() and fabric_pre_unlink() are used for
1455          * registration and release of TCM Loop Virtual SCSI LUNs.
1456          */
1457         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1458         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1459         fabric->tf_ops.fabric_make_np = NULL;
1460         fabric->tf_ops.fabric_drop_np = NULL;
1461         /*
1462          * Setup default attribute lists for various fabric->tf_cit_tmpl
1463          */
1464         fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1465         fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1466         fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
1467         fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
1468         fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
1469         /*
1470          * Once fabric->tf_ops has been setup, now register the fabric for
1471          * use within TCM
1472          */
1473         ret = target_fabric_configfs_register(fabric);
1474         if (ret < 0) {
1475                 pr_err("target_fabric_configfs_register() for"
1476                                 " TCM_Loop failed!\n");
1477                 target_fabric_configfs_free(fabric);
1478                 return -1;
1479         }
1480         /*
1481          * Setup our local pointer to *fabric.
1482          */
1483         tcm_loop_fabric_configfs = fabric;
1484         pr_debug("TCM_LOOP[0] - Set fabric ->"
1485                         " tcm_loop_fabric_configfs\n");
1486         return 0;
1487 }
1488
1489 static void tcm_loop_deregister_configfs(void)
1490 {
1491         if (!tcm_loop_fabric_configfs)
1492                 return;
1493
1494         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1495         tcm_loop_fabric_configfs = NULL;
1496         pr_debug("TCM_LOOP[0] - Cleared"
1497                                 " tcm_loop_fabric_configfs\n");
1498 }
1499
1500 static int __init tcm_loop_fabric_init(void)
1501 {
1502         int ret = -ENOMEM;
1503
1504         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1505         if (!tcm_loop_workqueue)
1506                 goto out;
1507
1508         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1509                                 sizeof(struct tcm_loop_cmd),
1510                                 __alignof__(struct tcm_loop_cmd),
1511                                 0, NULL);
1512         if (!tcm_loop_cmd_cache) {
1513                 pr_debug("kmem_cache_create() for"
1514                         " tcm_loop_cmd_cache failed\n");
1515                 goto out_destroy_workqueue;
1516         }
1517
1518         ret = tcm_loop_alloc_core_bus();
1519         if (ret)
1520                 goto out_destroy_cache;
1521
1522         ret = tcm_loop_register_configfs();
1523         if (ret)
1524                 goto out_release_core_bus;
1525
1526         return 0;
1527
1528 out_release_core_bus:
1529         tcm_loop_release_core_bus();
1530 out_destroy_cache:
1531         kmem_cache_destroy(tcm_loop_cmd_cache);
1532 out_destroy_workqueue:
1533         destroy_workqueue(tcm_loop_workqueue);
1534 out:
1535         return ret;
1536 }
1537
1538 static void __exit tcm_loop_fabric_exit(void)
1539 {
1540         tcm_loop_deregister_configfs();
1541         tcm_loop_release_core_bus();
1542         kmem_cache_destroy(tcm_loop_cmd_cache);
1543         destroy_workqueue(tcm_loop_workqueue);
1544 }
1545
1546 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1547 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1548 MODULE_LICENSE("GPL");
1549 module_init(tcm_loop_fabric_init);
1550 module_exit(tcm_loop_fabric_exit);