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