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, TCM_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, TCM_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         .eh_abort_handler = tcm_loop_abort_task,
 373         .eh_device_reset_handler = tcm_loop_device_reset,
 374         .eh_target_reset_handler = tcm_loop_target_reset,
 375         .can_queue              = 1024,
 376         .this_id                = -1,
 377         .sg_tablesize           = 256,
 378         .cmd_per_lun            = 1024,
 379         .max_sectors            = 0xFFFF,
 380         .use_clustering         = DISABLE_CLUSTERING,
 381         .slave_alloc            = tcm_loop_slave_alloc,
 382         .module                 = THIS_MODULE,
 383         .use_blk_tags           = 1,
 384         .track_queue_depth      = 1,
 385 };
 386
 387 static int tcm_loop_driver_probe(struct device *dev)
 388 {
 389         struct tcm_loop_hba *tl_hba;
 390         struct Scsi_Host *sh;
 391         int error, host_prot;
 392
 393         tl_hba = to_tcm_loop_hba(dev);
 394
 395         sh = scsi_host_alloc(&tcm_loop_driver_template,
 396                         sizeof(struct tcm_loop_hba));
 397         if (!sh) {
 398                 pr_err("Unable to allocate struct scsi_host\n");
 399                 return -ENODEV;
 400         }
 401         tl_hba->sh = sh;
 402
 403         /*
 404          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 405          */
 406         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 407         /*
 408          * Setup single ID, Channel and LUN for now..
 409          */
 410         sh->max_id = 2;
 411         sh->max_lun = 0;
 412         sh->max_channel = 0;
 413         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 414
 415         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 416                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 417                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 418
 419         scsi_host_set_prot(sh, host_prot);
 420         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 421
 422         error = scsi_add_host(sh, &tl_hba->dev);
 423         if (error) {
 424                 pr_err("%s: scsi_add_host failed\n", __func__);
 425                 scsi_host_put(sh);
 426                 return -ENODEV;
 427         }
 428         return 0;
 429 }
 430
 431 static int tcm_loop_driver_remove(struct device *dev)
 432 {
 433         struct tcm_loop_hba *tl_hba;
 434         struct Scsi_Host *sh;
 435
 436         tl_hba = to_tcm_loop_hba(dev);
 437         sh = tl_hba->sh;
 438
 439         scsi_remove_host(sh);
 440         scsi_host_put(sh);
 441         return 0;
 442 }
 443
 444 static void tcm_loop_release_adapter(struct device *dev)
 445 {
 446         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 447
 448         kfree(tl_hba);
 449 }
 450
 451 /*
 452  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 453  */
 454 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 455 {
 456         int ret;
 457
 458         tl_hba->dev.bus = &tcm_loop_lld_bus;
 459         tl_hba->dev.parent = tcm_loop_primary;
 460         tl_hba->dev.release = &tcm_loop_release_adapter;
 461         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 462
 463         ret = device_register(&tl_hba->dev);
 464         if (ret) {
 465                 pr_err("device_register() failed for"
 466                                 " tl_hba->dev: %d\n", ret);
 467                 return -ENODEV;
 468         }
 469
 470         return 0;
 471 }
 472
 473 /*
 474  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 475  * tcm_loop SCSI bus.
 476  */
 477 static int tcm_loop_alloc_core_bus(void)
 478 {
 479         int ret;
 480
 481         tcm_loop_primary = root_device_register("tcm_loop_0");
 482         if (IS_ERR(tcm_loop_primary)) {
 483                 pr_err("Unable to allocate tcm_loop_primary\n");
 484                 return PTR_ERR(tcm_loop_primary);
 485         }
 486
 487         ret = bus_register(&tcm_loop_lld_bus);
 488         if (ret) {
 489                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 490                 goto dev_unreg;
 491         }
 492
 493         ret = driver_register(&tcm_loop_driverfs);
 494         if (ret) {
 495                 pr_err("driver_register() failed for"
 496                                 "tcm_loop_driverfs\n");
 497                 goto bus_unreg;
 498         }
 499
 500         pr_debug("Initialized TCM Loop Core Bus\n");
 501         return ret;
 502
 503 bus_unreg:
 504         bus_unregister(&tcm_loop_lld_bus);
 505 dev_unreg:
 506         root_device_unregister(tcm_loop_primary);
 507         return ret;
 508 }
 509
 510 static void tcm_loop_release_core_bus(void)
 511 {
 512         driver_unregister(&tcm_loop_driverfs);
 513         bus_unregister(&tcm_loop_lld_bus);
 514         root_device_unregister(tcm_loop_primary);
 515
 516         pr_debug("Releasing TCM Loop Core BUS\n");
 517 }
 518
 519 static char *tcm_loop_get_fabric_name(void)
 520 {
 521         return "loopback";
 522 }
 523
 524 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 525 {
 526         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 527         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 528         /*
 529          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 530          * time based on the protocol dependent prefix of the passed configfs group.
 531          *
 532          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 533          * ProtocolID using target_core_fabric_lib.c symbols.
 534          */
 535         switch (tl_hba->tl_proto_id) {
 536         case SCSI_PROTOCOL_SAS:
 537                 return sas_get_fabric_proto_ident(se_tpg);
 538         case SCSI_PROTOCOL_FCP:
 539                 return fc_get_fabric_proto_ident(se_tpg);
 540         case SCSI_PROTOCOL_ISCSI:
 541                 return iscsi_get_fabric_proto_ident(se_tpg);
 542         default:
 543                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 544                         " SAS emulation\n", tl_hba->tl_proto_id);
 545                 break;
 546         }
 547
 548         return sas_get_fabric_proto_ident(se_tpg);
 549 }
 550
 551 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 552 {
 553         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 554         /*
 555          * Return the passed NAA identifier for the SAS Target Port
 556          */
 557         return &tl_tpg->tl_hba->tl_wwn_address[0];
 558 }
 559
 560 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 561 {
 562         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 563         /*
 564          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 565          * to represent the SCSI Target Port.
 566          */
 567         return tl_tpg->tl_tpgt;
 568 }
 569
 570 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 571 {
 572         return 1;
 573 }
 574
 575 static u32 tcm_loop_get_pr_transport_id(
 576         struct se_portal_group *se_tpg,
 577         struct se_node_acl *se_nacl,
 578         struct t10_pr_registration *pr_reg,
 579         int *format_code,
 580         unsigned char *buf)
 581 {
 582         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 583         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 584
 585         switch (tl_hba->tl_proto_id) {
 586         case SCSI_PROTOCOL_SAS:
 587                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 588                                         format_code, buf);
 589         case SCSI_PROTOCOL_FCP:
 590                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 591                                         format_code, buf);
 592         case SCSI_PROTOCOL_ISCSI:
 593                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 594                                         format_code, buf);
 595         default:
 596                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 597                         " SAS emulation\n", tl_hba->tl_proto_id);
 598                 break;
 599         }
 600
 601         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 602                         format_code, buf);
 603 }
 604
 605 static u32 tcm_loop_get_pr_transport_id_len(
 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 {
 611         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 612         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 613
 614         switch (tl_hba->tl_proto_id) {
 615         case SCSI_PROTOCOL_SAS:
 616                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 617                                         format_code);
 618         case SCSI_PROTOCOL_FCP:
 619                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 620                                         format_code);
 621         case SCSI_PROTOCOL_ISCSI:
 622                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 623                                         format_code);
 624         default:
 625                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 626                         " SAS emulation\n", tl_hba->tl_proto_id);
 627                 break;
 628         }
 629
 630         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 631                         format_code);
 632 }
 633
 634 /*
 635  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 636  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 637  */
 638 static char *tcm_loop_parse_pr_out_transport_id(
 639         struct se_portal_group *se_tpg,
 640         const char *buf,
 641         u32 *out_tid_len,
 642         char **port_nexus_ptr)
 643 {
 644         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 645         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 646
 647         switch (tl_hba->tl_proto_id) {
 648         case SCSI_PROTOCOL_SAS:
 649                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 650                                         port_nexus_ptr);
 651         case SCSI_PROTOCOL_FCP:
 652                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 653                                         port_nexus_ptr);
 654         case SCSI_PROTOCOL_ISCSI:
 655                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 656                                         port_nexus_ptr);
 657         default:
 658                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 659                         " SAS emulation\n", tl_hba->tl_proto_id);
 660                 break;
 661         }
 662
 663         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 664                         port_nexus_ptr);
 665 }
 666
 667 /*
 668  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 669  * based upon the incoming fabric dependent SCSI Initiator Port
 670  */
 671 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 672 {
 673         return 1;
 674 }
 675
 676 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 677 {
 678         return 0;
 679 }
 680
 681 /*
 682  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 683  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 684  */
 685 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 686 {
 687         return 0;
 688 }
 689
 690 /*
 691  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 692  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 693  * It has been added here as a nop for target_fabric_tf_ops_check()
 694  */
 695 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 696 {
 697         return 0;
 698 }
 699
 700 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 701         struct se_portal_group *se_tpg)
 702 {
 703         struct tcm_loop_nacl *tl_nacl;
 704
 705         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 706         if (!tl_nacl) {
 707                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 708                 return NULL;
 709         }
 710
 711         return &tl_nacl->se_node_acl;
 712 }
 713
 714 static void tcm_loop_tpg_release_fabric_acl(
 715         struct se_portal_group *se_tpg,
 716         struct se_node_acl *se_nacl)
 717 {
 718         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 719                                 struct tcm_loop_nacl, se_node_acl);
 720
 721         kfree(tl_nacl);
 722 }
 723
 724 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 725 {
 726         return 1;
 727 }
 728
 729 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 730 {
 731         return 1;
 732 }
 733
 734 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 735 {
 736         return;
 737 }
 738
 739 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 740 {
 741         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 742                         struct tcm_loop_cmd, tl_se_cmd);
 743
 744         return tl_cmd->sc_cmd_tag;
 745 }
 746
 747 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 748 {
 749         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 750                         struct tcm_loop_cmd, tl_se_cmd);
 751
 752         return tl_cmd->sc_cmd_state;
 753 }
 754
 755 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 756 {
 757         return 0;
 758 }
 759
 760 static void tcm_loop_close_session(struct se_session *se_sess)
 761 {
 762         return;
 763 };
 764
 765 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 766 {
 767         /*
 768          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 769          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 770          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 771          * format with transport_generic_map_mem_to_cmd().
 772          *
 773          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 774          * object execution queue.
 775          */
 776         target_execute_cmd(se_cmd);
 777         return 0;
 778 }
 779
 780 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 781 {
 782         return 0;
 783 }
 784
 785 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 786 {
 787         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 788                                 struct tcm_loop_cmd, tl_se_cmd);
 789         struct scsi_cmnd *sc = tl_cmd->sc;
 790
 791         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 792                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 793
 794         sc->result = SAM_STAT_GOOD;
 795         set_host_byte(sc, DID_OK);
 796         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 797             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 798                 scsi_set_resid(sc, se_cmd->residual_count);
 799         sc->scsi_done(sc);
 800         return 0;
 801 }
 802
 803 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 804 {
 805         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 806                                 struct tcm_loop_cmd, tl_se_cmd);
 807         struct scsi_cmnd *sc = tl_cmd->sc;
 808
 809         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 810                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 811
 812         if (se_cmd->sense_buffer &&
 813            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 814             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 815
 816                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 817                                 SCSI_SENSE_BUFFERSIZE);
 818                 sc->result = SAM_STAT_CHECK_CONDITION;
 819                 set_driver_byte(sc, DRIVER_SENSE);
 820         } else
 821                 sc->result = se_cmd->scsi_status;
 822
 823         set_host_byte(sc, DID_OK);
 824         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 825             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 826                 scsi_set_resid(sc, se_cmd->residual_count);
 827         sc->scsi_done(sc);
 828         return 0;
 829 }
 830
 831 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 832 {
 833         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 834         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 835         /*
 836          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 837          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 838          */
 839         atomic_set(&tl_tmr->tmr_complete, 1);
 840         wake_up(&tl_tmr->tl_tmr_wait);
 841 }
 842
 843 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 844 {
 845         return;
 846 }
 847
 848 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 849 {
 850         switch (tl_hba->tl_proto_id) {
 851         case SCSI_PROTOCOL_SAS:
 852                 return "SAS";
 853         case SCSI_PROTOCOL_FCP:
 854                 return "FCP";
 855         case SCSI_PROTOCOL_ISCSI:
 856                 return "iSCSI";
 857         default:
 858                 break;
 859         }
 860
 861         return "Unknown";
 862 }
 863
 864 /* Start items for tcm_loop_port_cit */
 865
 866 static int tcm_loop_port_link(
 867         struct se_portal_group *se_tpg,
 868         struct se_lun *lun)
 869 {
 870         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 871                                 struct tcm_loop_tpg, tl_se_tpg);
 872         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 873
 874         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 875         /*
 876          * Add Linux/SCSI struct scsi_device by HCTL
 877          */
 878         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 879
 880         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 881         return 0;
 882 }
 883
 884 static void tcm_loop_port_unlink(
 885         struct se_portal_group *se_tpg,
 886         struct se_lun *se_lun)
 887 {
 888         struct scsi_device *sd;
 889         struct tcm_loop_hba *tl_hba;
 890         struct tcm_loop_tpg *tl_tpg;
 891
 892         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 893         tl_hba = tl_tpg->tl_hba;
 894
 895         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 896                                 se_lun->unpacked_lun);
 897         if (!sd) {
 898                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 899                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 900                 return;
 901         }
 902         /*
 903          * Remove Linux/SCSI struct scsi_device by HCTL
 904          */
 905         scsi_remove_device(sd);
 906         scsi_device_put(sd);
 907
 908         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 909
 910         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 911 }
 912
 913 /* End items for tcm_loop_port_cit */
 914
 915 /* Start items for tcm_loop_nexus_cit */
 916
 917 static int tcm_loop_make_nexus(
 918         struct tcm_loop_tpg *tl_tpg,
 919         const char *name)
 920 {
 921         struct se_portal_group *se_tpg;
 922         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 923         struct tcm_loop_nexus *tl_nexus;
 924         int ret = -ENOMEM;
 925
 926         if (tl_tpg->tl_nexus) {
 927                 pr_debug("tl_tpg->tl_nexus already exists\n");
 928                 return -EEXIST;
 929         }
 930         se_tpg = &tl_tpg->tl_se_tpg;
 931
 932         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 933         if (!tl_nexus) {
 934                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 935                 return -ENOMEM;
 936         }
 937         /*
 938          * Initialize the struct se_session pointer
 939          */
 940         tl_nexus->se_sess = transport_init_session(TARGET_PROT_ALL);
 941         if (IS_ERR(tl_nexus->se_sess)) {
 942                 ret = PTR_ERR(tl_nexus->se_sess);
 943                 goto out;
 944         }
 945         /*
 946          * Since we are running in 'demo mode' this call with generate a
 947          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
 948          * Initiator port name of the passed configfs group 'name'.
 949          */
 950         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 951                                 se_tpg, (unsigned char *)name);
 952         if (!tl_nexus->se_sess->se_node_acl) {
 953                 transport_free_session(tl_nexus->se_sess);
 954                 goto out;
 955         }
 956         /* Now, register the SAS I_T Nexus as active. */
 957         transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
 958                         tl_nexus->se_sess, tl_nexus);
 959         tl_tpg->tl_nexus = tl_nexus;
 960         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 961                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 962                 name);
 963         return 0;
 964
 965 out:
 966         kfree(tl_nexus);
 967         return ret;
 968 }
 969
 970 static int tcm_loop_drop_nexus(
 971         struct tcm_loop_tpg *tpg)
 972 {
 973         struct se_session *se_sess;
 974         struct tcm_loop_nexus *tl_nexus;
 975
 976         tl_nexus = tpg->tl_nexus;
 977         if (!tl_nexus)
 978                 return -ENODEV;
 979
 980         se_sess = tl_nexus->se_sess;
 981         if (!se_sess)
 982                 return -ENODEV;
 983
 984         if (atomic_read(&tpg->tl_tpg_port_count)) {
 985                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
 986                         " active TPG port count: %d\n",
 987                         atomic_read(&tpg->tl_tpg_port_count));
 988                 return -EPERM;
 989         }
 990
 991         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
 992                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
 993                 tl_nexus->se_sess->se_node_acl->initiatorname);
 994         /*
 995          * Release the SCSI I_T Nexus to the emulated SAS Target Port
 996          */
 997         transport_deregister_session(tl_nexus->se_sess);
 998         tpg->tl_nexus = NULL;
 999         kfree(tl_nexus);
1000         return 0;
1001 }
1002
1003 /* End items for tcm_loop_nexus_cit */
1004
1005 static ssize_t tcm_loop_tpg_show_nexus(
1006         struct se_portal_group *se_tpg,
1007         char *page)
1008 {
1009         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1010                         struct tcm_loop_tpg, tl_se_tpg);
1011         struct tcm_loop_nexus *tl_nexus;
1012         ssize_t ret;
1013
1014         tl_nexus = tl_tpg->tl_nexus;
1015         if (!tl_nexus)
1016                 return -ENODEV;
1017
1018         ret = snprintf(page, PAGE_SIZE, "%s\n",
1019                 tl_nexus->se_sess->se_node_acl->initiatorname);
1020
1021         return ret;
1022 }
1023
1024 static ssize_t tcm_loop_tpg_store_nexus(
1025         struct se_portal_group *se_tpg,
1026         const char *page,
1027         size_t count)
1028 {
1029         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1030                         struct tcm_loop_tpg, tl_se_tpg);
1031         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1032         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1033         int ret;
1034         /*
1035          * Shutdown the active I_T nexus if 'NULL' is passed..
1036          */
1037         if (!strncmp(page, "NULL", 4)) {
1038                 ret = tcm_loop_drop_nexus(tl_tpg);
1039                 return (!ret) ? count : ret;
1040         }
1041         /*
1042          * Otherwise make sure the passed virtual Initiator port WWN matches
1043          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1044          * tcm_loop_make_nexus()
1045          */
1046         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1047                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1048                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1049                 return -EINVAL;
1050         }
1051         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1052
1053         ptr = strstr(i_port, "naa.");
1054         if (ptr) {
1055                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1056                         pr_err("Passed SAS Initiator Port %s does not"
1057                                 " match target port protoid: %s\n", i_port,
1058                                 tcm_loop_dump_proto_id(tl_hba));
1059                         return -EINVAL;
1060                 }
1061                 port_ptr = &i_port[0];
1062                 goto check_newline;
1063         }
1064         ptr = strstr(i_port, "fc.");
1065         if (ptr) {
1066                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1067                         pr_err("Passed FCP Initiator Port %s does not"
1068                                 " match target port protoid: %s\n", i_port,
1069                                 tcm_loop_dump_proto_id(tl_hba));
1070                         return -EINVAL;
1071                 }
1072                 port_ptr = &i_port[3]; /* Skip over "fc." */
1073                 goto check_newline;
1074         }
1075         ptr = strstr(i_port, "iqn.");
1076         if (ptr) {
1077                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1078                         pr_err("Passed iSCSI Initiator Port %s does not"
1079                                 " match target port protoid: %s\n", i_port,
1080                                 tcm_loop_dump_proto_id(tl_hba));
1081                         return -EINVAL;
1082                 }
1083                 port_ptr = &i_port[0];
1084                 goto check_newline;
1085         }
1086         pr_err("Unable to locate prefix for emulated Initiator Port:"
1087                         " %s\n", i_port);
1088         return -EINVAL;
1089         /*
1090          * Clear any trailing newline for the NAA WWN
1091          */
1092 check_newline:
1093         if (i_port[strlen(i_port)-1] == '\n')
1094                 i_port[strlen(i_port)-1] = '\0';
1095
1096         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1097         if (ret < 0)
1098                 return ret;
1099
1100         return count;
1101 }
1102
1103 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1104
1105 static ssize_t tcm_loop_tpg_show_transport_status(
1106         struct se_portal_group *se_tpg,
1107         char *page)
1108 {
1109         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1110                         struct tcm_loop_tpg, tl_se_tpg);
1111         const char *status = NULL;
1112         ssize_t ret = -EINVAL;
1113
1114         switch (tl_tpg->tl_transport_status) {
1115         case TCM_TRANSPORT_ONLINE:
1116                 status = "online";
1117                 break;
1118         case TCM_TRANSPORT_OFFLINE:
1119                 status = "offline";
1120                 break;
1121         default:
1122                 break;
1123         }
1124
1125         if (status)
1126                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1127
1128         return ret;
1129 }
1130
1131 static ssize_t tcm_loop_tpg_store_transport_status(
1132         struct se_portal_group *se_tpg,
1133         const char *page,
1134         size_t count)
1135 {
1136         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1137                         struct tcm_loop_tpg, tl_se_tpg);
1138
1139         if (!strncmp(page, "online", 6)) {
1140                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1141                 return count;
1142         }
1143         if (!strncmp(page, "offline", 7)) {
1144                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1145                 return count;
1146         }
1147         return -EINVAL;
1148 }
1149
1150 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1151
1152 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1153         &tcm_loop_tpg_nexus.attr,
1154         &tcm_loop_tpg_transport_status.attr,
1155         NULL,
1156 };
1157
1158 /* Start items for tcm_loop_naa_cit */
1159
1160 static struct se_portal_group *tcm_loop_make_naa_tpg(
1161         struct se_wwn *wwn,
1162         struct config_group *group,
1163         const char *name)
1164 {
1165         struct tcm_loop_hba *tl_hba = container_of(wwn,
1166                         struct tcm_loop_hba, tl_hba_wwn);
1167         struct tcm_loop_tpg *tl_tpg;
1168         char *tpgt_str, *end_ptr;
1169         int ret;
1170         unsigned short int tpgt;
1171
1172         tpgt_str = strstr(name, "tpgt_");
1173         if (!tpgt_str) {
1174                 pr_err("Unable to locate \"tpgt_#\" directory"
1175                                 " group\n");
1176                 return ERR_PTR(-EINVAL);
1177         }
1178         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1179         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1180
1181         if (tpgt >= TL_TPGS_PER_HBA) {
1182                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1183                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1184                 return ERR_PTR(-EINVAL);
1185         }
1186         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1187         tl_tpg->tl_hba = tl_hba;
1188         tl_tpg->tl_tpgt = tpgt;
1189         /*
1190          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1191          */
1192         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1193                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1194                         TRANSPORT_TPG_TYPE_NORMAL);
1195         if (ret < 0)
1196                 return ERR_PTR(-ENOMEM);
1197
1198         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1199                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1200                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1201
1202         return &tl_tpg->tl_se_tpg;
1203 }
1204
1205 static void tcm_loop_drop_naa_tpg(
1206         struct se_portal_group *se_tpg)
1207 {
1208         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1209         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1210                                 struct tcm_loop_tpg, tl_se_tpg);
1211         struct tcm_loop_hba *tl_hba;
1212         unsigned short tpgt;
1213
1214         tl_hba = tl_tpg->tl_hba;
1215         tpgt = tl_tpg->tl_tpgt;
1216         /*
1217          * Release the I_T Nexus for the Virtual SAS link if present
1218          */
1219         tcm_loop_drop_nexus(tl_tpg);
1220         /*
1221          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1222          */
1223         core_tpg_deregister(se_tpg);
1224
1225         tl_tpg->tl_hba = NULL;
1226         tl_tpg->tl_tpgt = 0;
1227
1228         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1229                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1230                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1231 }
1232
1233 /* End items for tcm_loop_naa_cit */
1234
1235 /* Start items for tcm_loop_cit */
1236
1237 static struct se_wwn *tcm_loop_make_scsi_hba(
1238         struct target_fabric_configfs *tf,
1239         struct config_group *group,
1240         const char *name)
1241 {
1242         struct tcm_loop_hba *tl_hba;
1243         struct Scsi_Host *sh;
1244         char *ptr;
1245         int ret, off = 0;
1246
1247         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1248         if (!tl_hba) {
1249                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1250                 return ERR_PTR(-ENOMEM);
1251         }
1252         /*
1253          * Determine the emulated Protocol Identifier and Target Port Name
1254          * based on the incoming configfs directory name.
1255          */
1256         ptr = strstr(name, "naa.");
1257         if (ptr) {
1258                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1259                 goto check_len;
1260         }
1261         ptr = strstr(name, "fc.");
1262         if (ptr) {
1263                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1264                 off = 3; /* Skip over "fc." */
1265                 goto check_len;
1266         }
1267         ptr = strstr(name, "iqn.");
1268         if (!ptr) {
1269                 pr_err("Unable to locate prefix for emulated Target "
1270                                 "Port: %s\n", name);
1271                 ret = -EINVAL;
1272                 goto out;
1273         }
1274         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1275
1276 check_len:
1277         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1278                 pr_err("Emulated NAA %s Address: %s, exceeds"
1279                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1280                         TL_WWN_ADDR_LEN);
1281                 ret = -EINVAL;
1282                 goto out;
1283         }
1284         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1285
1286         /*
1287          * Call device_register(tl_hba->dev) to register the emulated
1288          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1289          * device_register() callbacks in tcm_loop_driver_probe()
1290          */
1291         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1292         if (ret)
1293                 goto out;
1294
1295         sh = tl_hba->sh;
1296         tcm_loop_hba_no_cnt++;
1297         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1298                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1299                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1300
1301         return &tl_hba->tl_hba_wwn;
1302 out:
1303         kfree(tl_hba);
1304         return ERR_PTR(ret);
1305 }
1306
1307 static void tcm_loop_drop_scsi_hba(
1308         struct se_wwn *wwn)
1309 {
1310         struct tcm_loop_hba *tl_hba = container_of(wwn,
1311                                 struct tcm_loop_hba, tl_hba_wwn);
1312
1313         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1314                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1315                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1316         /*
1317          * Call device_unregister() on the original tl_hba->dev.
1318          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1319          * release *tl_hba;
1320          */
1321         device_unregister(&tl_hba->dev);
1322 }
1323
1324 /* Start items for tcm_loop_cit */
1325 static ssize_t tcm_loop_wwn_show_attr_version(
1326         struct target_fabric_configfs *tf,
1327         char *page)
1328 {
1329         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1330 }
1331
1332 TF_WWN_ATTR_RO(tcm_loop, version);
1333
1334 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1335         &tcm_loop_wwn_version.attr,
1336         NULL,
1337 };
1338
1339 /* End items for tcm_loop_cit */
1340
1341 static int tcm_loop_register_configfs(void)
1342 {
1343         struct target_fabric_configfs *fabric;
1344         int ret;
1345         /*
1346          * Set the TCM Loop HBA counter to zero
1347          */
1348         tcm_loop_hba_no_cnt = 0;
1349         /*
1350          * Register the top level struct config_item_type with TCM core
1351          */
1352         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1353         if (IS_ERR(fabric)) {
1354                 pr_err("tcm_loop_register_configfs() failed!\n");
1355                 return PTR_ERR(fabric);
1356         }
1357         /*
1358          * Setup the fabric API of function pointers used by target_core_mod
1359          */
1360         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1361         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1362         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1363         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1364         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1365         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1366         fabric->tf_ops.tpg_get_pr_transport_id_len =
1367                                         &tcm_loop_get_pr_transport_id_len;
1368         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1369                                         &tcm_loop_parse_pr_out_transport_id;
1370         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1371         fabric->tf_ops.tpg_check_demo_mode_cache =
1372                                         &tcm_loop_check_demo_mode_cache;
1373         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1374                                         &tcm_loop_check_demo_mode_write_protect;
1375         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1376                                         &tcm_loop_check_prod_mode_write_protect;
1377         /*
1378          * The TCM loopback fabric module runs in demo-mode to a local
1379          * virtual SCSI device, so fabric dependent initator ACLs are
1380          * not required.
1381          */
1382         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1383         fabric->tf_ops.tpg_release_fabric_acl =
1384                                         &tcm_loop_tpg_release_fabric_acl;
1385         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1386         /*
1387          * Used for setting up remaining TCM resources in process context
1388          */
1389         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1390         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1391         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1392         fabric->tf_ops.close_session = &tcm_loop_close_session;
1393         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1394         fabric->tf_ops.sess_get_initiator_sid = NULL;
1395         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1396         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1397         /*
1398          * Not used for TCM loopback
1399          */
1400         fabric->tf_ops.set_default_node_attributes =
1401                                         &tcm_loop_set_default_node_attributes;
1402         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1403         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1404         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1405         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1406         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1407         fabric->tf_ops.aborted_task = &tcm_loop_aborted_task;
1408
1409         /*
1410          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1411          */
1412         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1413         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1414         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1415         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1416         /*
1417          * fabric_post_link() and fabric_pre_unlink() are used for
1418          * registration and release of TCM Loop Virtual SCSI LUNs.
1419          */
1420         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1421         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1422         fabric->tf_ops.fabric_make_np = NULL;
1423         fabric->tf_ops.fabric_drop_np = NULL;
1424         /*
1425          * Setup default attribute lists for various fabric->tf_cit_tmpl
1426          */
1427         fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1428         fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1429         fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
1430         fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
1431         fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
1432         /*
1433          * Once fabric->tf_ops has been setup, now register the fabric for
1434          * use within TCM
1435          */
1436         ret = target_fabric_configfs_register(fabric);
1437         if (ret < 0) {
1438                 pr_err("target_fabric_configfs_register() for"
1439                                 " TCM_Loop failed!\n");
1440                 target_fabric_configfs_free(fabric);
1441                 return -1;
1442         }
1443         /*
1444          * Setup our local pointer to *fabric.
1445          */
1446         tcm_loop_fabric_configfs = fabric;
1447         pr_debug("TCM_LOOP[0] - Set fabric ->"
1448                         " tcm_loop_fabric_configfs\n");
1449         return 0;
1450 }
1451
1452 static void tcm_loop_deregister_configfs(void)
1453 {
1454         if (!tcm_loop_fabric_configfs)
1455                 return;
1456
1457         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1458         tcm_loop_fabric_configfs = NULL;
1459         pr_debug("TCM_LOOP[0] - Cleared"
1460                                 " tcm_loop_fabric_configfs\n");
1461 }
1462
1463 static int __init tcm_loop_fabric_init(void)
1464 {
1465         int ret = -ENOMEM;
1466
1467         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1468         if (!tcm_loop_workqueue)
1469                 goto out;
1470
1471         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1472                                 sizeof(struct tcm_loop_cmd),
1473                                 __alignof__(struct tcm_loop_cmd),
1474                                 0, NULL);
1475         if (!tcm_loop_cmd_cache) {
1476                 pr_debug("kmem_cache_create() for"
1477                         " tcm_loop_cmd_cache failed\n");
1478                 goto out_destroy_workqueue;
1479         }
1480
1481         ret = tcm_loop_alloc_core_bus();
1482         if (ret)
1483                 goto out_destroy_cache;
1484
1485         ret = tcm_loop_register_configfs();
1486         if (ret)
1487                 goto out_release_core_bus;
1488
1489         return 0;
1490
1491 out_release_core_bus:
1492         tcm_loop_release_core_bus();
1493 out_destroy_cache:
1494         kmem_cache_destroy(tcm_loop_cmd_cache);
1495 out_destroy_workqueue:
1496         destroy_workqueue(tcm_loop_workqueue);
1497 out:
1498         return ret;
1499 }
1500
1501 static void __exit tcm_loop_fabric_exit(void)
1502 {
1503         tcm_loop_deregister_configfs();
1504         tcm_loop_release_core_bus();
1505         kmem_cache_destroy(tcm_loop_cmd_cache);
1506         destroy_workqueue(tcm_loop_workqueue);
1507 }
1508
1509 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1510 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1511 MODULE_LICENSE("GPL");
1512 module_init(tcm_loop_fabric_init);
1513 module_exit(tcm_loop_fabric_exit);