Pileus Git - ~andy/linux/blob - 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_transport.h>
  37 #include <target/target_core_fabric_ops.h>
  38 #include <target/target_core_fabric_configfs.h>
  39 #include <target/target_core_fabric_lib.h>
  40 #include <target/target_core_configfs.h>
  41 #include <target/target_core_device.h>
  42 #include <target/target_core_tpg.h>
  43 #include <target/target_core_tmr.h>
  44
  45 #include "tcm_loop.h"
  46
  47 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
  48
  49 /* Local pointer to allocated TCM configfs fabric module */
  50 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  51
  52 static struct kmem_cache *tcm_loop_cmd_cache;
  53
  54 static int tcm_loop_hba_no_cnt;
  55
  56 /*
  57  * Allocate a tcm_loop cmd descriptor from target_core_mod code
  58  *
  59  * Can be called from interrupt context in tcm_loop_queuecommand() below
  60  */
  61 static struct se_cmd *tcm_loop_allocate_core_cmd(
  62         struct tcm_loop_hba *tl_hba,
  63         struct se_portal_group *se_tpg,
  64         struct scsi_cmnd *sc)
  65 {
  66         struct se_cmd *se_cmd;
  67         struct se_session *se_sess;
  68         struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus;
  69         struct tcm_loop_cmd *tl_cmd;
  70         int sam_task_attr;
  71
  72         if (!tl_nexus) {
  73                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
  74                                 " does not exist\n");
  75                 set_host_byte(sc, DID_ERROR);
  76                 return NULL;
  77         }
  78         se_sess = tl_nexus->se_sess;
  79
  80         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
  81         if (!tl_cmd) {
  82                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
  83                 set_host_byte(sc, DID_ERROR);
  84                 return NULL;
  85         }
  86         se_cmd = &tl_cmd->tl_se_cmd;
  87         /*
  88          * Save the pointer to struct scsi_cmnd *sc
  89          */
  90         tl_cmd->sc = sc;
  91         /*
  92          * Locate the SAM Task Attr from struct scsi_cmnd *
  93          */
  94         if (sc->device->tagged_supported) {
  95                 switch (sc->tag) {
  96                 case HEAD_OF_QUEUE_TAG:
  97                         sam_task_attr = MSG_HEAD_TAG;
  98                         break;
  99                 case ORDERED_QUEUE_TAG:
 100                         sam_task_attr = MSG_ORDERED_TAG;
 101                         break;
 102                 default:
 103                         sam_task_attr = MSG_SIMPLE_TAG;
 104                         break;
 105                 }
 106         } else
 107                 sam_task_attr = MSG_SIMPLE_TAG;
 108
 109         /*
 110          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 111          */
 112         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
 113                         scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr,
 114                         &tl_cmd->tl_sense_buf[0]);
 115
 116         /*
 117          * Signal BIDI usage with T_TASK(cmd)->t_tasks_bidi
 118          */
 119         if (scsi_bidi_cmnd(sc))
 120                 se_cmd->t_tasks_bidi = 1;
 121         /*
 122          * Locate the struct se_lun pointer and attach it to struct se_cmd
 123          */
 124         if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
 125                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 126                 set_host_byte(sc, DID_NO_CONNECT);
 127                 return NULL;
 128         }
 129
 130         return se_cmd;
 131 }
 132
 133 /*
 134  * Called by struct target_core_fabric_ops->new_cmd_map()
 135  *
 136  * Always called in process context.  A non zero return value
 137  * here will signal to handle an exception based on the return code.
 138  */
 139 static int tcm_loop_new_cmd_map(struct se_cmd *se_cmd)
 140 {
 141         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 142                                 struct tcm_loop_cmd, tl_se_cmd);
 143         struct scsi_cmnd *sc = tl_cmd->sc;
 144         struct scatterlist *sgl_bidi = NULL;
 145         u32 sgl_bidi_count = 0;
 146         int ret;
 147         /*
 148          * Allocate the necessary tasks to complete the received CDB+data
 149          */
 150         ret = transport_generic_allocate_tasks(se_cmd, sc->cmnd);
 151         if (ret == -ENOMEM) {
 152                 /* Out of Resources */
 153                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 154         } else if (ret == -EINVAL) {
 155                 /*
 156                  * Handle case for SAM_STAT_RESERVATION_CONFLICT
 157                  */
 158                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
 159                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
 160                 /*
 161                  * Otherwise, return SAM_STAT_CHECK_CONDITION and return
 162                  * sense data.
 163                  */
 164                 return PYX_TRANSPORT_USE_SENSE_REASON;
 165         }
 166
 167         /*
 168          * For BIDI commands, pass in the extra READ buffer
 169          * to transport_generic_map_mem_to_cmd() below..
 170          */
 171         if (se_cmd->t_tasks_bidi) {
 172                 struct scsi_data_buffer *sdb = scsi_in(sc);
 173
 174                 sgl_bidi = sdb->table.sgl;
 175                 sgl_bidi_count = sdb->table.nents;
 176         }
 177
 178         /* Tell the core about our preallocated memory */
 179         ret = transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),
 180                         scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);
 181         if (ret < 0)
 182                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 183
 184         return 0;
 185 }
 186
 187 /*
 188  * Called from struct target_core_fabric_ops->check_stop_free()
 189  */
 190 static void tcm_loop_check_stop_free(struct se_cmd *se_cmd)
 191 {
 192         /*
 193          * Do not release struct se_cmd's containing a valid TMR
 194          * pointer.  These will be released directly in tcm_loop_device_reset()
 195          * with transport_generic_free_cmd().
 196          */
 197         if (se_cmd->se_tmr_req)
 198                 return;
 199         /*
 200          * Release the struct se_cmd, which will make a callback to release
 201          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
 202          */
 203         transport_generic_free_cmd(se_cmd, 0, 0);
 204 }
 205
 206 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
 207 {
 208         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 209                                 struct tcm_loop_cmd, tl_se_cmd);
 210
 211         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 212 }
 213
 214 static int tcm_loop_proc_info(struct Scsi_Host *host, char *buffer,
 215                                 char **start, off_t offset,
 216                                 int length, int inout)
 217 {
 218         return sprintf(buffer, "tcm_loop_proc_info()\n");
 219 }
 220
 221 static int tcm_loop_driver_probe(struct device *);
 222 static int tcm_loop_driver_remove(struct device *);
 223
 224 static int pseudo_lld_bus_match(struct device *dev,
 225                                 struct device_driver *dev_driver)
 226 {
 227         return 1;
 228 }
 229
 230 static struct bus_type tcm_loop_lld_bus = {
 231         .name                   = "tcm_loop_bus",
 232         .match                  = pseudo_lld_bus_match,
 233         .probe                  = tcm_loop_driver_probe,
 234         .remove                 = tcm_loop_driver_remove,
 235 };
 236
 237 static struct device_driver tcm_loop_driverfs = {
 238         .name                   = "tcm_loop",
 239         .bus                    = &tcm_loop_lld_bus,
 240 };
 241 /*
 242  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 243  */
 244 struct device *tcm_loop_primary;
 245
 246 /*
 247  * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
 248  * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
 249  */
 250 static int tcm_loop_change_queue_depth(
 251         struct scsi_device *sdev,
 252         int depth,
 253         int reason)
 254 {
 255         switch (reason) {
 256         case SCSI_QDEPTH_DEFAULT:
 257                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 258                 break;
 259         case SCSI_QDEPTH_QFULL:
 260                 scsi_track_queue_full(sdev, depth);
 261                 break;
 262         case SCSI_QDEPTH_RAMP_UP:
 263                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 264                 break;
 265         default:
 266                 return -EOPNOTSUPP;
 267         }
 268         return sdev->queue_depth;
 269 }
 270
 271 /*
 272  * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data
 273  * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs)
 274  */
 275 static int tcm_loop_queuecommand(
 276         struct Scsi_Host *sh,
 277         struct scsi_cmnd *sc)
 278 {
 279         struct se_cmd *se_cmd;
 280         struct se_portal_group *se_tpg;
 281         struct tcm_loop_hba *tl_hba;
 282         struct tcm_loop_tpg *tl_tpg;
 283
 284         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
 285                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 286                 sc->device->id, sc->device->channel, sc->device->lun,
 287                 sc->cmnd[0], scsi_bufflen(sc));
 288         /*
 289          * Locate the tcm_loop_hba_t pointer
 290          */
 291         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 292         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 293         se_tpg = &tl_tpg->tl_se_tpg;
 294         /*
 295          * Determine the SAM Task Attribute and allocate tl_cmd and
 296          * tl_cmd->tl_se_cmd from TCM infrastructure
 297          */
 298         se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
 299         if (!se_cmd) {
 300                 sc->scsi_done(sc);
 301                 return 0;
 302         }
 303         /*
 304          * Queue up the newly allocated to be processed in TCM thread context.
 305         */
 306         transport_generic_handle_cdb_map(se_cmd);
 307         return 0;
 308 }
 309
 310 /*
 311  * Called from SCSI EH process context to issue a LUN_RESET TMR
 312  * to struct scsi_device
 313  */
 314 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 315 {
 316         struct se_cmd *se_cmd = NULL;
 317         struct se_portal_group *se_tpg;
 318         struct se_session *se_sess;
 319         struct tcm_loop_cmd *tl_cmd = NULL;
 320         struct tcm_loop_hba *tl_hba;
 321         struct tcm_loop_nexus *tl_nexus;
 322         struct tcm_loop_tmr *tl_tmr = NULL;
 323         struct tcm_loop_tpg *tl_tpg;
 324         int ret = FAILED;
 325         /*
 326          * Locate the tcm_loop_hba_t pointer
 327          */
 328         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 329         /*
 330          * Locate the tl_nexus and se_sess pointers
 331          */
 332         tl_nexus = tl_hba->tl_nexus;
 333         if (!tl_nexus) {
 334                 pr_err("Unable to perform device reset without"
 335                                 " active I_T Nexus\n");
 336                 return FAILED;
 337         }
 338         se_sess = tl_nexus->se_sess;
 339         /*
 340          * Locate the tl_tpg and se_tpg pointers from TargetID in sc->device->id
 341          */
 342         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 343         se_tpg = &tl_tpg->tl_se_tpg;
 344
 345         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 346         if (!tl_cmd) {
 347                 pr_err("Unable to allocate memory for tl_cmd\n");
 348                 return FAILED;
 349         }
 350
 351         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 352         if (!tl_tmr) {
 353                 pr_err("Unable to allocate memory for tl_tmr\n");
 354                 goto release;
 355         }
 356         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 357
 358         se_cmd = &tl_cmd->tl_se_cmd;
 359         /*
 360          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 361          */
 362         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 363                                 DMA_NONE, MSG_SIMPLE_TAG,
 364                                 &tl_cmd->tl_sense_buf[0]);
 365         /*
 366          * Allocate the LUN_RESET TMR
 367          */
 368         se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, tl_tmr,
 369                                 TMR_LUN_RESET);
 370         if (IS_ERR(se_cmd->se_tmr_req))
 371                 goto release;
 372         /*
 373          * Locate the underlying TCM struct se_lun from sc->device->lun
 374          */
 375         if (transport_lookup_tmr_lun(se_cmd, sc->device->lun) < 0)
 376                 goto release;
 377         /*
 378          * Queue the TMR to TCM Core and sleep waiting for tcm_loop_queue_tm_rsp()
 379          * to wake us up.
 380          */
 381         transport_generic_handle_tmr(se_cmd);
 382         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 383         /*
 384          * The TMR LUN_RESET has completed, check the response status and
 385          * then release allocations.
 386          */
 387         ret = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
 388                 SUCCESS : FAILED;
 389 release:
 390         if (se_cmd)
 391                 transport_generic_free_cmd(se_cmd, 1, 0);
 392         else
 393                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 394         kfree(tl_tmr);
 395         return ret;
 396 }
 397
 398 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 399 {
 400         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 401         return 0;
 402 }
 403
 404 static int tcm_loop_slave_configure(struct scsi_device *sd)
 405 {
 406         return 0;
 407 }
 408
 409 static struct scsi_host_template tcm_loop_driver_template = {
 410         .proc_info              = tcm_loop_proc_info,
 411         .proc_name              = "tcm_loopback",
 412         .name                   = "TCM_Loopback",
 413         .queuecommand           = tcm_loop_queuecommand,
 414         .change_queue_depth     = tcm_loop_change_queue_depth,
 415         .eh_device_reset_handler = tcm_loop_device_reset,
 416         .can_queue              = TL_SCSI_CAN_QUEUE,
 417         .this_id                = -1,
 418         .sg_tablesize           = TL_SCSI_SG_TABLESIZE,
 419         .cmd_per_lun            = TL_SCSI_CMD_PER_LUN,
 420         .max_sectors            = TL_SCSI_MAX_SECTORS,
 421         .use_clustering         = DISABLE_CLUSTERING,
 422         .slave_alloc            = tcm_loop_slave_alloc,
 423         .slave_configure        = tcm_loop_slave_configure,
 424         .module                 = THIS_MODULE,
 425 };
 426
 427 static int tcm_loop_driver_probe(struct device *dev)
 428 {
 429         struct tcm_loop_hba *tl_hba;
 430         struct Scsi_Host *sh;
 431         int error;
 432
 433         tl_hba = to_tcm_loop_hba(dev);
 434
 435         sh = scsi_host_alloc(&tcm_loop_driver_template,
 436                         sizeof(struct tcm_loop_hba));
 437         if (!sh) {
 438                 pr_err("Unable to allocate struct scsi_host\n");
 439                 return -ENODEV;
 440         }
 441         tl_hba->sh = sh;
 442
 443         /*
 444          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 445          */
 446         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 447         /*
 448          * Setup single ID, Channel and LUN for now..
 449          */
 450         sh->max_id = 2;
 451         sh->max_lun = 0;
 452         sh->max_channel = 0;
 453         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 454
 455         error = scsi_add_host(sh, &tl_hba->dev);
 456         if (error) {
 457                 pr_err("%s: scsi_add_host failed\n", __func__);
 458                 scsi_host_put(sh);
 459                 return -ENODEV;
 460         }
 461         return 0;
 462 }
 463
 464 static int tcm_loop_driver_remove(struct device *dev)
 465 {
 466         struct tcm_loop_hba *tl_hba;
 467         struct Scsi_Host *sh;
 468
 469         tl_hba = to_tcm_loop_hba(dev);
 470         sh = tl_hba->sh;
 471
 472         scsi_remove_host(sh);
 473         scsi_host_put(sh);
 474         return 0;
 475 }
 476
 477 static void tcm_loop_release_adapter(struct device *dev)
 478 {
 479         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 480
 481         kfree(tl_hba);
 482 }
 483
 484 /*
 485  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 486  */
 487 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 488 {
 489         int ret;
 490
 491         tl_hba->dev.bus = &tcm_loop_lld_bus;
 492         tl_hba->dev.parent = tcm_loop_primary;
 493         tl_hba->dev.release = &tcm_loop_release_adapter;
 494         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 495
 496         ret = device_register(&tl_hba->dev);
 497         if (ret) {
 498                 pr_err("device_register() failed for"
 499                                 " tl_hba->dev: %d\n", ret);
 500                 return -ENODEV;
 501         }
 502
 503         return 0;
 504 }
 505
 506 /*
 507  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 508  * tcm_loop SCSI bus.
 509  */
 510 static int tcm_loop_alloc_core_bus(void)
 511 {
 512         int ret;
 513
 514         tcm_loop_primary = root_device_register("tcm_loop_0");
 515         if (IS_ERR(tcm_loop_primary)) {
 516                 pr_err("Unable to allocate tcm_loop_primary\n");
 517                 return PTR_ERR(tcm_loop_primary);
 518         }
 519
 520         ret = bus_register(&tcm_loop_lld_bus);
 521         if (ret) {
 522                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 523                 goto dev_unreg;
 524         }
 525
 526         ret = driver_register(&tcm_loop_driverfs);
 527         if (ret) {
 528                 pr_err("driver_register() failed for"
 529                                 "tcm_loop_driverfs\n");
 530                 goto bus_unreg;
 531         }
 532
 533         pr_debug("Initialized TCM Loop Core Bus\n");
 534         return ret;
 535
 536 bus_unreg:
 537         bus_unregister(&tcm_loop_lld_bus);
 538 dev_unreg:
 539         root_device_unregister(tcm_loop_primary);
 540         return ret;
 541 }
 542
 543 static void tcm_loop_release_core_bus(void)
 544 {
 545         driver_unregister(&tcm_loop_driverfs);
 546         bus_unregister(&tcm_loop_lld_bus);
 547         root_device_unregister(tcm_loop_primary);
 548
 549         pr_debug("Releasing TCM Loop Core BUS\n");
 550 }
 551
 552 static char *tcm_loop_get_fabric_name(void)
 553 {
 554         return "loopback";
 555 }
 556
 557 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 558 {
 559         struct tcm_loop_tpg *tl_tpg =
 560                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 561         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 562         /*
 563          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 564          * time based on the protocol dependent prefix of the passed configfs group.
 565          *
 566          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 567          * ProtocolID using target_core_fabric_lib.c symbols.
 568          */
 569         switch (tl_hba->tl_proto_id) {
 570         case SCSI_PROTOCOL_SAS:
 571                 return sas_get_fabric_proto_ident(se_tpg);
 572         case SCSI_PROTOCOL_FCP:
 573                 return fc_get_fabric_proto_ident(se_tpg);
 574         case SCSI_PROTOCOL_ISCSI:
 575                 return iscsi_get_fabric_proto_ident(se_tpg);
 576         default:
 577                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 578                         " SAS emulation\n", tl_hba->tl_proto_id);
 579                 break;
 580         }
 581
 582         return sas_get_fabric_proto_ident(se_tpg);
 583 }
 584
 585 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 586 {
 587         struct tcm_loop_tpg *tl_tpg =
 588                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 589         /*
 590          * Return the passed NAA identifier for the SAS Target Port
 591          */
 592         return &tl_tpg->tl_hba->tl_wwn_address[0];
 593 }
 594
 595 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 596 {
 597         struct tcm_loop_tpg *tl_tpg =
 598                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 599         /*
 600          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 601          * to represent the SCSI Target Port.
 602          */
 603         return tl_tpg->tl_tpgt;
 604 }
 605
 606 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 607 {
 608         return 1;
 609 }
 610
 611 static u32 tcm_loop_get_pr_transport_id(
 612         struct se_portal_group *se_tpg,
 613         struct se_node_acl *se_nacl,
 614         struct t10_pr_registration *pr_reg,
 615         int *format_code,
 616         unsigned char *buf)
 617 {
 618         struct tcm_loop_tpg *tl_tpg =
 619                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 620         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 621
 622         switch (tl_hba->tl_proto_id) {
 623         case SCSI_PROTOCOL_SAS:
 624                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 625                                         format_code, buf);
 626         case SCSI_PROTOCOL_FCP:
 627                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 628                                         format_code, buf);
 629         case SCSI_PROTOCOL_ISCSI:
 630                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 631                                         format_code, buf);
 632         default:
 633                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 634                         " SAS emulation\n", tl_hba->tl_proto_id);
 635                 break;
 636         }
 637
 638         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 639                         format_code, buf);
 640 }
 641
 642 static u32 tcm_loop_get_pr_transport_id_len(
 643         struct se_portal_group *se_tpg,
 644         struct se_node_acl *se_nacl,
 645         struct t10_pr_registration *pr_reg,
 646         int *format_code)
 647 {
 648         struct tcm_loop_tpg *tl_tpg =
 649                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 650         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 651
 652         switch (tl_hba->tl_proto_id) {
 653         case SCSI_PROTOCOL_SAS:
 654                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 655                                         format_code);
 656         case SCSI_PROTOCOL_FCP:
 657                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 658                                         format_code);
 659         case SCSI_PROTOCOL_ISCSI:
 660                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 661                                         format_code);
 662         default:
 663                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 664                         " SAS emulation\n", tl_hba->tl_proto_id);
 665                 break;
 666         }
 667
 668         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 669                         format_code);
 670 }
 671
 672 /*
 673  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 674  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 675  */
 676 static char *tcm_loop_parse_pr_out_transport_id(
 677         struct se_portal_group *se_tpg,
 678         const char *buf,
 679         u32 *out_tid_len,
 680         char **port_nexus_ptr)
 681 {
 682         struct tcm_loop_tpg *tl_tpg =
 683                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 684         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 685
 686         switch (tl_hba->tl_proto_id) {
 687         case SCSI_PROTOCOL_SAS:
 688                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 689                                         port_nexus_ptr);
 690         case SCSI_PROTOCOL_FCP:
 691                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 692                                         port_nexus_ptr);
 693         case SCSI_PROTOCOL_ISCSI:
 694                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 695                                         port_nexus_ptr);
 696         default:
 697                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 698                         " SAS emulation\n", tl_hba->tl_proto_id);
 699                 break;
 700         }
 701
 702         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 703                         port_nexus_ptr);
 704 }
 705
 706 /*
 707  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 708  * based upon the incoming fabric dependent SCSI Initiator Port
 709  */
 710 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 711 {
 712         return 1;
 713 }
 714
 715 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 716 {
 717         return 0;
 718 }
 719
 720 /*
 721  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 722  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 723  */
 724 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 725 {
 726         return 0;
 727 }
 728
 729 /*
 730  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 731  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 732  * It has been added here as a nop for target_fabric_tf_ops_check()
 733  */
 734 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 735 {
 736         return 0;
 737 }
 738
 739 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 740         struct se_portal_group *se_tpg)
 741 {
 742         struct tcm_loop_nacl *tl_nacl;
 743
 744         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 745         if (!tl_nacl) {
 746                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 747                 return NULL;
 748         }
 749
 750         return &tl_nacl->se_node_acl;
 751 }
 752
 753 static void tcm_loop_tpg_release_fabric_acl(
 754         struct se_portal_group *se_tpg,
 755         struct se_node_acl *se_nacl)
 756 {
 757         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 758                                 struct tcm_loop_nacl, se_node_acl);
 759
 760         kfree(tl_nacl);
 761 }
 762
 763 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 764 {
 765         return 1;
 766 }
 767
 768 static int tcm_loop_is_state_remove(struct se_cmd *se_cmd)
 769 {
 770         /*
 771          * Assume struct scsi_cmnd is not in remove state..
 772          */
 773         return 0;
 774 }
 775
 776 static int tcm_loop_sess_logged_in(struct se_session *se_sess)
 777 {
 778         /*
 779          * Assume that TL Nexus is always active
 780          */
 781         return 1;
 782 }
 783
 784 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 785 {
 786         return 1;
 787 }
 788
 789 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 790 {
 791         return;
 792 }
 793
 794 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 795 {
 796         return 1;
 797 }
 798
 799 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 800 {
 801         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 802                         struct tcm_loop_cmd, tl_se_cmd);
 803
 804         return tl_cmd->sc_cmd_state;
 805 }
 806
 807 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 808 {
 809         return 0;
 810 }
 811
 812 static void tcm_loop_close_session(struct se_session *se_sess)
 813 {
 814         return;
 815 };
 816
 817 static void tcm_loop_stop_session(
 818         struct se_session *se_sess,
 819         int sess_sleep,
 820         int conn_sleep)
 821 {
 822         return;
 823 }
 824
 825 static void tcm_loop_fall_back_to_erl0(struct se_session *se_sess)
 826 {
 827         return;
 828 }
 829
 830 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 831 {
 832         /*
 833          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 834          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 835          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 836          * format with transport_generic_map_mem_to_cmd().
 837          *
 838          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 839          * object execution queue.
 840          */
 841         transport_generic_process_write(se_cmd);
 842         return 0;
 843 }
 844
 845 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 846 {
 847         return 0;
 848 }
 849
 850 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 851 {
 852         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 853                                 struct tcm_loop_cmd, tl_se_cmd);
 854         struct scsi_cmnd *sc = tl_cmd->sc;
 855
 856         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 857                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 858
 859         sc->result = SAM_STAT_GOOD;
 860         set_host_byte(sc, DID_OK);
 861         sc->scsi_done(sc);
 862         return 0;
 863 }
 864
 865 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 866 {
 867         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 868                                 struct tcm_loop_cmd, tl_se_cmd);
 869         struct scsi_cmnd *sc = tl_cmd->sc;
 870
 871         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 872                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 873
 874         if (se_cmd->sense_buffer &&
 875            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 876             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 877
 878                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 879                                 SCSI_SENSE_BUFFERSIZE);
 880                 sc->result = SAM_STAT_CHECK_CONDITION;
 881                 set_driver_byte(sc, DRIVER_SENSE);
 882         } else
 883                 sc->result = se_cmd->scsi_status;
 884
 885         set_host_byte(sc, DID_OK);
 886         sc->scsi_done(sc);
 887         return 0;
 888 }
 889
 890 static int tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 891 {
 892         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 893         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 894         /*
 895          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 896          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 897          */
 898         atomic_set(&tl_tmr->tmr_complete, 1);
 899         wake_up(&tl_tmr->tl_tmr_wait);
 900         return 0;
 901 }
 902
 903 static u16 tcm_loop_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_length)
 904 {
 905         return 0;
 906 }
 907
 908 static u16 tcm_loop_get_fabric_sense_len(void)
 909 {
 910         return 0;
 911 }
 912
 913 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 914 {
 915         switch (tl_hba->tl_proto_id) {
 916         case SCSI_PROTOCOL_SAS:
 917                 return "SAS";
 918         case SCSI_PROTOCOL_FCP:
 919                 return "FCP";
 920         case SCSI_PROTOCOL_ISCSI:
 921                 return "iSCSI";
 922         default:
 923                 break;
 924         }
 925
 926         return "Unknown";
 927 }
 928
 929 /* Start items for tcm_loop_port_cit */
 930
 931 static int tcm_loop_port_link(
 932         struct se_portal_group *se_tpg,
 933         struct se_lun *lun)
 934 {
 935         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 936                                 struct tcm_loop_tpg, tl_se_tpg);
 937         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 938
 939         atomic_inc(&tl_tpg->tl_tpg_port_count);
 940         smp_mb__after_atomic_inc();
 941         /*
 942          * Add Linux/SCSI struct scsi_device by HCTL
 943          */
 944         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 945
 946         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 947         return 0;
 948 }
 949
 950 static void tcm_loop_port_unlink(
 951         struct se_portal_group *se_tpg,
 952         struct se_lun *se_lun)
 953 {
 954         struct scsi_device *sd;
 955         struct tcm_loop_hba *tl_hba;
 956         struct tcm_loop_tpg *tl_tpg;
 957
 958         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 959         tl_hba = tl_tpg->tl_hba;
 960
 961         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 962                                 se_lun->unpacked_lun);
 963         if (!sd) {
 964                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 965                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 966                 return;
 967         }
 968         /*
 969          * Remove Linux/SCSI struct scsi_device by HCTL
 970          */
 971         scsi_remove_device(sd);
 972         scsi_device_put(sd);
 973
 974         atomic_dec(&tl_tpg->tl_tpg_port_count);
 975         smp_mb__after_atomic_dec();
 976
 977         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 978 }
 979
 980 /* End items for tcm_loop_port_cit */
 981
 982 /* Start items for tcm_loop_nexus_cit */
 983
 984 static int tcm_loop_make_nexus(
 985         struct tcm_loop_tpg *tl_tpg,
 986         const char *name)
 987 {
 988         struct se_portal_group *se_tpg;
 989         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 990         struct tcm_loop_nexus *tl_nexus;
 991         int ret = -ENOMEM;
 992
 993         if (tl_tpg->tl_hba->tl_nexus) {
 994                 pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
 995                 return -EEXIST;
 996         }
 997         se_tpg = &tl_tpg->tl_se_tpg;
 998
 999         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
1000         if (!tl_nexus) {
1001                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
1002                 return -ENOMEM;
1003         }
1004         /*
1005          * Initialize the struct se_session pointer
1006          */
1007         tl_nexus->se_sess = transport_init_session();
1008         if (IS_ERR(tl_nexus->se_sess)) {
1009                 ret = PTR_ERR(tl_nexus->se_sess);
1010                 goto out;
1011         }
1012         /*
1013          * Since we are running in 'demo mode' this call with generate a
1014          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
1015          * Initiator port name of the passed configfs group 'name'.
1016          */
1017         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1018                                 se_tpg, (unsigned char *)name);
1019         if (!tl_nexus->se_sess->se_node_acl) {
1020                 transport_free_session(tl_nexus->se_sess);
1021                 goto out;
1022         }
1023         /*
1024          * Now, register the SAS I_T Nexus as active with the call to
1025          * transport_register_session()
1026          */
1027         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1028                         tl_nexus->se_sess, tl_nexus);
1029         tl_tpg->tl_hba->tl_nexus = tl_nexus;
1030         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1031                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1032                 name);
1033         return 0;
1034
1035 out:
1036         kfree(tl_nexus);
1037         return ret;
1038 }
1039
1040 static int tcm_loop_drop_nexus(
1041         struct tcm_loop_tpg *tpg)
1042 {
1043         struct se_session *se_sess;
1044         struct tcm_loop_nexus *tl_nexus;
1045         struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1046
1047         tl_nexus = tpg->tl_hba->tl_nexus;
1048         if (!tl_nexus)
1049                 return -ENODEV;
1050
1051         se_sess = tl_nexus->se_sess;
1052         if (!se_sess)
1053                 return -ENODEV;
1054
1055         if (atomic_read(&tpg->tl_tpg_port_count)) {
1056                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
1057                         " active TPG port count: %d\n",
1058                         atomic_read(&tpg->tl_tpg_port_count));
1059                 return -EPERM;
1060         }
1061
1062         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1063                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1064                 tl_nexus->se_sess->se_node_acl->initiatorname);
1065         /*
1066          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1067          */
1068         transport_deregister_session(tl_nexus->se_sess);
1069         tpg->tl_hba->tl_nexus = NULL;
1070         kfree(tl_nexus);
1071         return 0;
1072 }
1073
1074 /* End items for tcm_loop_nexus_cit */
1075
1076 static ssize_t tcm_loop_tpg_show_nexus(
1077         struct se_portal_group *se_tpg,
1078         char *page)
1079 {
1080         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1081                         struct tcm_loop_tpg, tl_se_tpg);
1082         struct tcm_loop_nexus *tl_nexus;
1083         ssize_t ret;
1084
1085         tl_nexus = tl_tpg->tl_hba->tl_nexus;
1086         if (!tl_nexus)
1087                 return -ENODEV;
1088
1089         ret = snprintf(page, PAGE_SIZE, "%s\n",
1090                 tl_nexus->se_sess->se_node_acl->initiatorname);
1091
1092         return ret;
1093 }
1094
1095 static ssize_t tcm_loop_tpg_store_nexus(
1096         struct se_portal_group *se_tpg,
1097         const char *page,
1098         size_t count)
1099 {
1100         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1101                         struct tcm_loop_tpg, tl_se_tpg);
1102         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1103         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1104         int ret;
1105         /*
1106          * Shutdown the active I_T nexus if 'NULL' is passed..
1107          */
1108         if (!strncmp(page, "NULL", 4)) {
1109                 ret = tcm_loop_drop_nexus(tl_tpg);
1110                 return (!ret) ? count : ret;
1111         }
1112         /*
1113          * Otherwise make sure the passed virtual Initiator port WWN matches
1114          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1115          * tcm_loop_make_nexus()
1116          */
1117         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1118                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1119                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1120                 return -EINVAL;
1121         }
1122         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1123
1124         ptr = strstr(i_port, "naa.");
1125         if (ptr) {
1126                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1127                         pr_err("Passed SAS Initiator Port %s does not"
1128                                 " match target port protoid: %s\n", i_port,
1129                                 tcm_loop_dump_proto_id(tl_hba));
1130                         return -EINVAL;
1131                 }
1132                 port_ptr = &i_port[0];
1133                 goto check_newline;
1134         }
1135         ptr = strstr(i_port, "fc.");
1136         if (ptr) {
1137                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1138                         pr_err("Passed FCP Initiator Port %s does not"
1139                                 " match target port protoid: %s\n", i_port,
1140                                 tcm_loop_dump_proto_id(tl_hba));
1141                         return -EINVAL;
1142                 }
1143                 port_ptr = &i_port[3]; /* Skip over "fc." */
1144                 goto check_newline;
1145         }
1146         ptr = strstr(i_port, "iqn.");
1147         if (ptr) {
1148                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1149                         pr_err("Passed iSCSI Initiator Port %s does not"
1150                                 " match target port protoid: %s\n", i_port,
1151                                 tcm_loop_dump_proto_id(tl_hba));
1152                         return -EINVAL;
1153                 }
1154                 port_ptr = &i_port[0];
1155                 goto check_newline;
1156         }
1157         pr_err("Unable to locate prefix for emulated Initiator Port:"
1158                         " %s\n", i_port);
1159         return -EINVAL;
1160         /*
1161          * Clear any trailing newline for the NAA WWN
1162          */
1163 check_newline:
1164         if (i_port[strlen(i_port)-1] == '\n')
1165                 i_port[strlen(i_port)-1] = '\0';
1166
1167         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1168         if (ret < 0)
1169                 return ret;
1170
1171         return count;
1172 }
1173
1174 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1175
1176 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1177         &tcm_loop_tpg_nexus.attr,
1178         NULL,
1179 };
1180
1181 /* Start items for tcm_loop_naa_cit */
1182
1183 struct se_portal_group *tcm_loop_make_naa_tpg(
1184         struct se_wwn *wwn,
1185         struct config_group *group,
1186         const char *name)
1187 {
1188         struct tcm_loop_hba *tl_hba = container_of(wwn,
1189                         struct tcm_loop_hba, tl_hba_wwn);
1190         struct tcm_loop_tpg *tl_tpg;
1191         char *tpgt_str, *end_ptr;
1192         int ret;
1193         unsigned short int tpgt;
1194
1195         tpgt_str = strstr(name, "tpgt_");
1196         if (!tpgt_str) {
1197                 pr_err("Unable to locate \"tpgt_#\" directory"
1198                                 " group\n");
1199                 return ERR_PTR(-EINVAL);
1200         }
1201         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1202         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1203
1204         if (tpgt >= TL_TPGS_PER_HBA) {
1205                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1206                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1207                 return ERR_PTR(-EINVAL);
1208         }
1209         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1210         tl_tpg->tl_hba = tl_hba;
1211         tl_tpg->tl_tpgt = tpgt;
1212         /*
1213          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1214          */
1215         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1216                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1217                         TRANSPORT_TPG_TYPE_NORMAL);
1218         if (ret < 0)
1219                 return ERR_PTR(-ENOMEM);
1220
1221         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1222                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1223                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1224
1225         return &tl_tpg->tl_se_tpg;
1226 }
1227
1228 void tcm_loop_drop_naa_tpg(
1229         struct se_portal_group *se_tpg)
1230 {
1231         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1232         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1233                                 struct tcm_loop_tpg, tl_se_tpg);
1234         struct tcm_loop_hba *tl_hba;
1235         unsigned short tpgt;
1236
1237         tl_hba = tl_tpg->tl_hba;
1238         tpgt = tl_tpg->tl_tpgt;
1239         /*
1240          * Release the I_T Nexus for the Virtual SAS link if present
1241          */
1242         tcm_loop_drop_nexus(tl_tpg);
1243         /*
1244          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1245          */
1246         core_tpg_deregister(se_tpg);
1247
1248         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1249                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1250                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1251 }
1252
1253 /* End items for tcm_loop_naa_cit */
1254
1255 /* Start items for tcm_loop_cit */
1256
1257 struct se_wwn *tcm_loop_make_scsi_hba(
1258         struct target_fabric_configfs *tf,
1259         struct config_group *group,
1260         const char *name)
1261 {
1262         struct tcm_loop_hba *tl_hba;
1263         struct Scsi_Host *sh;
1264         char *ptr;
1265         int ret, off = 0;
1266
1267         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1268         if (!tl_hba) {
1269                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1270                 return ERR_PTR(-ENOMEM);
1271         }
1272         /*
1273          * Determine the emulated Protocol Identifier and Target Port Name
1274          * based on the incoming configfs directory name.
1275          */
1276         ptr = strstr(name, "naa.");
1277         if (ptr) {
1278                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1279                 goto check_len;
1280         }
1281         ptr = strstr(name, "fc.");
1282         if (ptr) {
1283                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1284                 off = 3; /* Skip over "fc." */
1285                 goto check_len;
1286         }
1287         ptr = strstr(name, "iqn.");
1288         if (!ptr) {
1289                 pr_err("Unable to locate prefix for emulated Target "
1290                                 "Port: %s\n", name);
1291                 ret = -EINVAL;
1292                 goto out;
1293         }
1294         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1295
1296 check_len:
1297         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1298                 pr_err("Emulated NAA %s Address: %s, exceeds"
1299                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1300                         TL_WWN_ADDR_LEN);
1301                 ret = -EINVAL;
1302                 goto out;
1303         }
1304         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1305
1306         /*
1307          * Call device_register(tl_hba->dev) to register the emulated
1308          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1309          * device_register() callbacks in tcm_loop_driver_probe()
1310          */
1311         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1312         if (ret)
1313                 goto out;
1314
1315         sh = tl_hba->sh;
1316         tcm_loop_hba_no_cnt++;
1317         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1318                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1319                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1320
1321         return &tl_hba->tl_hba_wwn;
1322 out:
1323         kfree(tl_hba);
1324         return ERR_PTR(ret);
1325 }
1326
1327 void tcm_loop_drop_scsi_hba(
1328         struct se_wwn *wwn)
1329 {
1330         struct tcm_loop_hba *tl_hba = container_of(wwn,
1331                                 struct tcm_loop_hba, tl_hba_wwn);
1332         int host_no = tl_hba->sh->host_no;
1333         /*
1334          * Call device_unregister() on the original tl_hba->dev.
1335          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1336          * release *tl_hba;
1337          */
1338         device_unregister(&tl_hba->dev);
1339
1340         pr_debug("TCM_Loop_ConfigFS: Deallocated emulated Target"
1341                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1342                 config_item_name(&wwn->wwn_group.cg_item), host_no);
1343 }
1344
1345 /* Start items for tcm_loop_cit */
1346 static ssize_t tcm_loop_wwn_show_attr_version(
1347         struct target_fabric_configfs *tf,
1348         char *page)
1349 {
1350         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1351 }
1352
1353 TF_WWN_ATTR_RO(tcm_loop, version);
1354
1355 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1356         &tcm_loop_wwn_version.attr,
1357         NULL,
1358 };
1359
1360 /* End items for tcm_loop_cit */
1361
1362 static int tcm_loop_register_configfs(void)
1363 {
1364         struct target_fabric_configfs *fabric;
1365         struct config_group *tf_cg;
1366         int ret;
1367         /*
1368          * Set the TCM Loop HBA counter to zero
1369          */
1370         tcm_loop_hba_no_cnt = 0;
1371         /*
1372          * Register the top level struct config_item_type with TCM core
1373          */
1374         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1375         if (IS_ERR(fabric)) {
1376                 pr_err("tcm_loop_register_configfs() failed!\n");
1377                 return PTR_ERR(fabric);
1378         }
1379         /*
1380          * Setup the fabric API of function pointers used by target_core_mod
1381          */
1382         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1383         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1384         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1385         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1386         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1387         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1388         fabric->tf_ops.tpg_get_pr_transport_id_len =
1389                                         &tcm_loop_get_pr_transport_id_len;
1390         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1391                                         &tcm_loop_parse_pr_out_transport_id;
1392         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1393         fabric->tf_ops.tpg_check_demo_mode_cache =
1394                                         &tcm_loop_check_demo_mode_cache;
1395         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1396                                         &tcm_loop_check_demo_mode_write_protect;
1397         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1398                                         &tcm_loop_check_prod_mode_write_protect;
1399         /*
1400          * The TCM loopback fabric module runs in demo-mode to a local
1401          * virtual SCSI device, so fabric dependent initator ACLs are
1402          * not required.
1403          */
1404         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1405         fabric->tf_ops.tpg_release_fabric_acl =
1406                                         &tcm_loop_tpg_release_fabric_acl;
1407         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1408         /*
1409          * Used for setting up remaining TCM resources in process context
1410          */
1411         fabric->tf_ops.new_cmd_map = &tcm_loop_new_cmd_map;
1412         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1413         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1414         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1415         fabric->tf_ops.close_session = &tcm_loop_close_session;
1416         fabric->tf_ops.stop_session = &tcm_loop_stop_session;
1417         fabric->tf_ops.fall_back_to_erl0 = &tcm_loop_fall_back_to_erl0;
1418         fabric->tf_ops.sess_logged_in = &tcm_loop_sess_logged_in;
1419         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1420         fabric->tf_ops.sess_get_initiator_sid = NULL;
1421         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1422         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1423         /*
1424          * Not used for TCM loopback
1425          */
1426         fabric->tf_ops.set_default_node_attributes =
1427                                         &tcm_loop_set_default_node_attributes;
1428         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1429         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1430         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1431         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1432         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1433         fabric->tf_ops.set_fabric_sense_len = &tcm_loop_set_fabric_sense_len;
1434         fabric->tf_ops.get_fabric_sense_len = &tcm_loop_get_fabric_sense_len;
1435         fabric->tf_ops.is_state_remove = &tcm_loop_is_state_remove;
1436
1437         tf_cg = &fabric->tf_group;
1438         /*
1439          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1440          */
1441         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1442         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1443         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1444         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1445         /*
1446          * fabric_post_link() and fabric_pre_unlink() are used for
1447          * registration and release of TCM Loop Virtual SCSI LUNs.
1448          */
1449         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1450         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1451         fabric->tf_ops.fabric_make_np = NULL;
1452         fabric->tf_ops.fabric_drop_np = NULL;
1453         /*
1454          * Setup default attribute lists for various fabric->tf_cit_tmpl
1455          */
1456         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1457         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1458         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1459         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1460         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1461         /*
1462          * Once fabric->tf_ops has been setup, now register the fabric for
1463          * use within TCM
1464          */
1465         ret = target_fabric_configfs_register(fabric);
1466         if (ret < 0) {
1467                 pr_err("target_fabric_configfs_register() for"
1468                                 " TCM_Loop failed!\n");
1469                 target_fabric_configfs_free(fabric);
1470                 return -1;
1471         }
1472         /*
1473          * Setup our local pointer to *fabric.
1474          */
1475         tcm_loop_fabric_configfs = fabric;
1476         pr_debug("TCM_LOOP[0] - Set fabric ->"
1477                         " tcm_loop_fabric_configfs\n");
1478         return 0;
1479 }
1480
1481 static void tcm_loop_deregister_configfs(void)
1482 {
1483         if (!tcm_loop_fabric_configfs)
1484                 return;
1485
1486         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1487         tcm_loop_fabric_configfs = NULL;
1488         pr_debug("TCM_LOOP[0] - Cleared"
1489                                 " tcm_loop_fabric_configfs\n");
1490 }
1491
1492 static int __init tcm_loop_fabric_init(void)
1493 {
1494         int ret;
1495
1496         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1497                                 sizeof(struct tcm_loop_cmd),
1498                                 __alignof__(struct tcm_loop_cmd),
1499                                 0, NULL);
1500         if (!tcm_loop_cmd_cache) {
1501                 pr_debug("kmem_cache_create() for"
1502                         " tcm_loop_cmd_cache failed\n");
1503                 return -ENOMEM;
1504         }
1505
1506         ret = tcm_loop_alloc_core_bus();
1507         if (ret)
1508                 return ret;
1509
1510         ret = tcm_loop_register_configfs();
1511         if (ret) {
1512                 tcm_loop_release_core_bus();
1513                 return ret;
1514         }
1515
1516         return 0;
1517 }
1518
1519 static void __exit tcm_loop_fabric_exit(void)
1520 {
1521         tcm_loop_deregister_configfs();
1522         tcm_loop_release_core_bus();
1523         kmem_cache_destroy(tcm_loop_cmd_cache);
1524 }
1525
1526 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1527 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1528 MODULE_LICENSE("GPL");
1529 module_init(tcm_loop_fabric_init);
1530 module_exit(tcm_loop_fabric_exit);