drivers/target/loopback/tcm_loop.c

   1 /*******************************************************************************
   2  *
   3  * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4  * for emulated SAS initiator ports
   5  *
   6  * © Copyright 2011-2013 Datera, Inc.
   7  *
   8  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9  *
  10  * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  ****************************************************************************/
  22
  23 #include <linux/module.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/init.h>
  26 #include <linux/slab.h>
  27 #include <linux/types.h>
  28 #include <linux/configfs.h>
  29 #include <scsi/scsi.h>
  30 #include <scsi/scsi_tcq.h>
  31 #include <scsi/scsi_host.h>
  32 #include <scsi/scsi_device.h>
  33 #include <scsi/scsi_cmnd.h>
  34
  35 #include <target/target_core_base.h>
  36 #include <target/target_core_fabric.h>
  37 #include <target/target_core_fabric_configfs.h>
  38 #include <target/target_core_configfs.h>
  39
  40 #include "tcm_loop.h"
  41
  42 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
  43
  44 /* Local pointer to allocated TCM configfs fabric module */
  45 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  46
  47 static struct workqueue_struct *tcm_loop_workqueue;
  48 static struct kmem_cache *tcm_loop_cmd_cache;
  49
  50 static int tcm_loop_hba_no_cnt;
  51
  52 static int tcm_loop_queue_status(struct se_cmd *se_cmd);
  53
  54 /*
  55  * Called from struct target_core_fabric_ops->check_stop_free()
  56  */
  57 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  58 {
  59         /*
  60          * Do not release struct se_cmd's containing a valid TMR
  61          * pointer.  These will be released directly in tcm_loop_device_reset()
  62          * with transport_generic_free_cmd().
  63          */
  64         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
  65                 return 0;
  66         /*
  67          * Release the struct se_cmd, which will make a callback to release
  68          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
  69          */
  70         transport_generic_free_cmd(se_cmd, 0);
  71         return 1;
  72 }
  73
  74 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  75 {
  76         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  77                                 struct tcm_loop_cmd, tl_se_cmd);
  78
  79         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  80 }
  81
  82 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  83 {
  84         seq_printf(m, "tcm_loop_proc_info()\n");
  85         return 0;
  86 }
  87
  88 static int tcm_loop_driver_probe(struct device *);
  89 static int tcm_loop_driver_remove(struct device *);
  90
  91 static int pseudo_lld_bus_match(struct device *dev,
  92                                 struct device_driver *dev_driver)
  93 {
  94         return 1;
  95 }
  96
  97 static struct bus_type tcm_loop_lld_bus = {
  98         .name                   = "tcm_loop_bus",
  99         .match                  = pseudo_lld_bus_match,
 100         .probe                  = tcm_loop_driver_probe,
 101         .remove                 = tcm_loop_driver_remove,
 102 };
 103
 104 static struct device_driver tcm_loop_driverfs = {
 105         .name                   = "tcm_loop",
 106         .bus                    = &tcm_loop_lld_bus,
 107 };
 108 /*
 109  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 110  */
 111 struct device *tcm_loop_primary;
 112
 113 static void tcm_loop_submission_work(struct work_struct *work)
 114 {
 115         struct tcm_loop_cmd *tl_cmd =
 116                 container_of(work, struct tcm_loop_cmd, work);
 117         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 118         struct scsi_cmnd *sc = tl_cmd->sc;
 119         struct tcm_loop_nexus *tl_nexus;
 120         struct tcm_loop_hba *tl_hba;
 121         struct tcm_loop_tpg *tl_tpg;
 122         struct scatterlist *sgl_bidi = NULL;
 123         u32 sgl_bidi_count = 0, transfer_length;
 124         int rc;
 125
 126         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 127         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 128
 129         /*
 130          * Ensure that this tl_tpg reference from the incoming sc->device->id
 131          * has already been configured via tcm_loop_make_naa_tpg().
 132          */
 133         if (!tl_tpg->tl_hba) {
 134                 set_host_byte(sc, DID_NO_CONNECT);
 135                 goto out_done;
 136         }
 137         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 138                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 139                 goto out_done;
 140         }
 141         tl_nexus = tl_hba->tl_nexus;
 142         if (!tl_nexus) {
 143                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
 144                                 " does not exist\n");
 145                 set_host_byte(sc, DID_ERROR);
 146                 goto out_done;
 147         }
 148         if (scsi_bidi_cmnd(sc)) {
 149                 struct scsi_data_buffer *sdb = scsi_in(sc);
 150
 151                 sgl_bidi = sdb->table.sgl;
 152                 sgl_bidi_count = sdb->table.nents;
 153                 se_cmd->se_cmd_flags |= SCF_BIDI;
 154
 155         }
 156
 157         transfer_length = scsi_transfer_length(sc);
 158         if (!scsi_prot_sg_count(sc) &&
 159             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 160                 se_cmd->prot_pto = true;
 161                 /*
 162                  * loopback transport doesn't support
 163                  * WRITE_GENERATE, READ_STRIP protection
 164                  * information operations, go ahead unprotected.
 165                  */
 166                 transfer_length = scsi_bufflen(sc);
 167         }
 168
 169         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 170                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 171                         transfer_length, MSG_SIMPLE_TAG,
 172                         sc->sc_data_direction, 0,
 173                         scsi_sglist(sc), scsi_sg_count(sc),
 174                         sgl_bidi, sgl_bidi_count,
 175                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 176         if (rc < 0) {
 177                 set_host_byte(sc, DID_NO_CONNECT);
 178                 goto out_done;
 179         }
 180         return;
 181
 182 out_done:
 183         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 184         sc->scsi_done(sc);
 185         return;
 186 }
 187
 188 /*
 189  * ->queuecommand can be and usually is called from interrupt context, so
 190  * defer the actual submission to a workqueue.
 191  */
 192 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 193 {
 194         struct tcm_loop_cmd *tl_cmd;
 195
 196         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
 197                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 198                 sc->device->id, sc->device->channel, sc->device->lun,
 199                 sc->cmnd[0], scsi_bufflen(sc));
 200
 201         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 202         if (!tl_cmd) {
 203                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
 204                 set_host_byte(sc, DID_ERROR);
 205                 sc->scsi_done(sc);
 206                 return 0;
 207         }
 208
 209         tl_cmd->sc = sc;
 210         tl_cmd->sc_cmd_tag = sc->request->tag;
 211         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 212         queue_work(tcm_loop_workqueue, &tl_cmd->work);
 213         return 0;
 214 }
 215
 216 /*
 217  * Called from SCSI EH process context to issue a LUN_RESET TMR
 218  * to struct scsi_device
 219  */
 220 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 221                               struct tcm_loop_nexus *tl_nexus,
 222                               int lun, int task, enum tcm_tmreq_table tmr)
 223 {
 224         struct se_cmd *se_cmd = NULL;
 225         struct se_session *se_sess;
 226         struct se_portal_group *se_tpg;
 227         struct tcm_loop_cmd *tl_cmd = NULL;
 228         struct tcm_loop_tmr *tl_tmr = NULL;
 229         int ret = TMR_FUNCTION_FAILED, rc;
 230
 231         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 232         if (!tl_cmd) {
 233                 pr_err("Unable to allocate memory for tl_cmd\n");
 234                 return ret;
 235         }
 236
 237         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 238         if (!tl_tmr) {
 239                 pr_err("Unable to allocate memory for tl_tmr\n");
 240                 goto release;
 241         }
 242         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 243
 244         se_cmd = &tl_cmd->tl_se_cmd;
 245         se_tpg = &tl_tpg->tl_se_tpg;
 246         se_sess = tl_nexus->se_sess;
 247         /*
 248          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 249          */
 250         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 251                                 DMA_NONE, MSG_SIMPLE_TAG,
 252                                 &tl_cmd->tl_sense_buf[0]);
 253
 254         rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
 255         if (rc < 0)
 256                 goto release;
 257
 258         if (tmr == TMR_ABORT_TASK)
 259                 se_cmd->se_tmr_req->ref_task_tag = task;
 260
 261         /*
 262          * Locate the underlying TCM struct se_lun
 263          */
 264         if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
 265                 ret = TMR_LUN_DOES_NOT_EXIST;
 266                 goto release;
 267         }
 268         /*
 269          * Queue the TMR to TCM Core and sleep waiting for
 270          * tcm_loop_queue_tm_rsp() to wake us up.
 271          */
 272         transport_generic_handle_tmr(se_cmd);
 273         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 274         /*
 275          * The TMR LUN_RESET has completed, check the response status and
 276          * then release allocations.
 277          */
 278         ret = se_cmd->se_tmr_req->response;
 279 release:
 280         if (se_cmd)
 281                 transport_generic_free_cmd(se_cmd, 1);
 282         else
 283                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 284         kfree(tl_tmr);
 285         return ret;
 286 }
 287
 288 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 289 {
 290         struct tcm_loop_hba *tl_hba;
 291         struct tcm_loop_nexus *tl_nexus;
 292         struct tcm_loop_tpg *tl_tpg;
 293         int ret = FAILED;
 294
 295         /*
 296          * Locate the tcm_loop_hba_t pointer
 297          */
 298         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 299         /*
 300          * Locate the tl_nexus and se_sess pointers
 301          */
 302         tl_nexus = tl_hba->tl_nexus;
 303         if (!tl_nexus) {
 304                 pr_err("Unable to perform device reset without"
 305                                 " active I_T Nexus\n");
 306                 return FAILED;
 307         }
 308
 309         /*
 310          * Locate the tl_tpg pointer from TargetID in sc->device->id
 311          */
 312         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 313         ret = tcm_loop_issue_tmr(tl_tpg, tl_nexus, sc->device->lun,
 314                                  sc->request->tag, TMR_ABORT_TASK);
 315         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 316 }
 317
 318 /*
 319  * Called from SCSI EH process context to issue a LUN_RESET TMR
 320  * to struct scsi_device
 321  */
 322 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 323 {
 324         struct tcm_loop_hba *tl_hba;
 325         struct tcm_loop_nexus *tl_nexus;
 326         struct tcm_loop_tpg *tl_tpg;
 327         int ret = FAILED;
 328
 329         /*
 330          * Locate the tcm_loop_hba_t pointer
 331          */
 332         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 333         /*
 334          * Locate the tl_nexus and se_sess pointers
 335          */
 336         tl_nexus = tl_hba->tl_nexus;
 337         if (!tl_nexus) {
 338                 pr_err("Unable to perform device reset without"
 339                                 " active I_T Nexus\n");
 340                 return FAILED;
 341         }
 342         /*
 343          * Locate the tl_tpg pointer from TargetID in sc->device->id
 344          */
 345         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 346         ret = tcm_loop_issue_tmr(tl_tpg, tl_nexus, sc->device->lun,
 347                                  0, TMR_LUN_RESET);
 348         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 349 }
 350
 351 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 352 {
 353         struct tcm_loop_hba *tl_hba;
 354         struct tcm_loop_tpg *tl_tpg;
 355
 356         /*
 357          * Locate the tcm_loop_hba_t pointer
 358          */
 359         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 360         if (!tl_hba) {
 361                 pr_err("Unable to perform device reset without"
 362                                 " active I_T Nexus\n");
 363                 return FAILED;
 364         }
 365         /*
 366          * Locate the tl_tpg pointer from TargetID in sc->device->id
 367          */
 368         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 369         if (tl_tpg) {
 370                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 371                 return SUCCESS;
 372         }
 373         return FAILED;
 374 }
 375
 376 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 377 {
 378         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 379         return 0;
 380 }
 381
 382 static struct scsi_host_template tcm_loop_driver_template = {
 383         .show_info              = tcm_loop_show_info,
 384         .proc_name              = "tcm_loopback",
 385         .name                   = "TCM_Loopback",
 386         .queuecommand           = tcm_loop_queuecommand,
 387         .change_queue_depth     = scsi_change_queue_depth,
 388         .change_queue_type      = scsi_change_queue_type,
 389         .eh_abort_handler = tcm_loop_abort_task,
 390         .eh_device_reset_handler = tcm_loop_device_reset,
 391         .eh_target_reset_handler = tcm_loop_target_reset,
 392         .can_queue              = 1024,
 393         .this_id                = -1,
 394         .sg_tablesize           = 256,
 395         .cmd_per_lun            = 1024,
 396         .max_sectors            = 0xFFFF,
 397         .use_clustering         = DISABLE_CLUSTERING,
 398         .slave_alloc            = tcm_loop_slave_alloc,
 399         .module                 = THIS_MODULE,
 400         .use_blk_tags           = 1,
 401         .track_queue_depth      = 1,
 402 };
 403
 404 static int tcm_loop_driver_probe(struct device *dev)
 405 {
 406         struct tcm_loop_hba *tl_hba;
 407         struct Scsi_Host *sh;
 408         int error, host_prot;
 409
 410         tl_hba = to_tcm_loop_hba(dev);
 411
 412         sh = scsi_host_alloc(&tcm_loop_driver_template,
 413                         sizeof(struct tcm_loop_hba));
 414         if (!sh) {
 415                 pr_err("Unable to allocate struct scsi_host\n");
 416                 return -ENODEV;
 417         }
 418         tl_hba->sh = sh;
 419
 420         /*
 421          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 422          */
 423         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 424         /*
 425          * Setup single ID, Channel and LUN for now..
 426          */
 427         sh->max_id = 2;
 428         sh->max_lun = 0;
 429         sh->max_channel = 0;
 430         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 431
 432         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 433                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 434                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 435
 436         scsi_host_set_prot(sh, host_prot);
 437         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 438
 439         error = scsi_add_host(sh, &tl_hba->dev);
 440         if (error) {
 441                 pr_err("%s: scsi_add_host failed\n", __func__);
 442                 scsi_host_put(sh);
 443                 return -ENODEV;
 444         }
 445         return 0;
 446 }
 447
 448 static int tcm_loop_driver_remove(struct device *dev)
 449 {
 450         struct tcm_loop_hba *tl_hba;
 451         struct Scsi_Host *sh;
 452
 453         tl_hba = to_tcm_loop_hba(dev);
 454         sh = tl_hba->sh;
 455
 456         scsi_remove_host(sh);
 457         scsi_host_put(sh);
 458         return 0;
 459 }
 460
 461 static void tcm_loop_release_adapter(struct device *dev)
 462 {
 463         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 464
 465         kfree(tl_hba);
 466 }
 467
 468 /*
 469  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 470  */
 471 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 472 {
 473         int ret;
 474
 475         tl_hba->dev.bus = &tcm_loop_lld_bus;
 476         tl_hba->dev.parent = tcm_loop_primary;
 477         tl_hba->dev.release = &tcm_loop_release_adapter;
 478         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 479
 480         ret = device_register(&tl_hba->dev);
 481         if (ret) {
 482                 pr_err("device_register() failed for"
 483                                 " tl_hba->dev: %d\n", ret);
 484                 return -ENODEV;
 485         }
 486
 487         return 0;
 488 }
 489
 490 /*
 491  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 492  * tcm_loop SCSI bus.
 493  */
 494 static int tcm_loop_alloc_core_bus(void)
 495 {
 496         int ret;
 497
 498         tcm_loop_primary = root_device_register("tcm_loop_0");
 499         if (IS_ERR(tcm_loop_primary)) {
 500                 pr_err("Unable to allocate tcm_loop_primary\n");
 501                 return PTR_ERR(tcm_loop_primary);
 502         }
 503
 504         ret = bus_register(&tcm_loop_lld_bus);
 505         if (ret) {
 506                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 507                 goto dev_unreg;
 508         }
 509
 510         ret = driver_register(&tcm_loop_driverfs);
 511         if (ret) {
 512                 pr_err("driver_register() failed for"
 513                                 "tcm_loop_driverfs\n");
 514                 goto bus_unreg;
 515         }
 516
 517         pr_debug("Initialized TCM Loop Core Bus\n");
 518         return ret;
 519
 520 bus_unreg:
 521         bus_unregister(&tcm_loop_lld_bus);
 522 dev_unreg:
 523         root_device_unregister(tcm_loop_primary);
 524         return ret;
 525 }
 526
 527 static void tcm_loop_release_core_bus(void)
 528 {
 529         driver_unregister(&tcm_loop_driverfs);
 530         bus_unregister(&tcm_loop_lld_bus);
 531         root_device_unregister(tcm_loop_primary);
 532
 533         pr_debug("Releasing TCM Loop Core BUS\n");
 534 }
 535
 536 static char *tcm_loop_get_fabric_name(void)
 537 {
 538         return "loopback";
 539 }
 540
 541 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 542 {
 543         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 544         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 545         /*
 546          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 547          * time based on the protocol dependent prefix of the passed configfs group.
 548          *
 549          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 550          * ProtocolID using target_core_fabric_lib.c symbols.
 551          */
 552         switch (tl_hba->tl_proto_id) {
 553         case SCSI_PROTOCOL_SAS:
 554                 return sas_get_fabric_proto_ident(se_tpg);
 555         case SCSI_PROTOCOL_FCP:
 556                 return fc_get_fabric_proto_ident(se_tpg);
 557         case SCSI_PROTOCOL_ISCSI:
 558                 return iscsi_get_fabric_proto_ident(se_tpg);
 559         default:
 560                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 561                         " SAS emulation\n", tl_hba->tl_proto_id);
 562                 break;
 563         }
 564
 565         return sas_get_fabric_proto_ident(se_tpg);
 566 }
 567
 568 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 569 {
 570         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 571         /*
 572          * Return the passed NAA identifier for the SAS Target Port
 573          */
 574         return &tl_tpg->tl_hba->tl_wwn_address[0];
 575 }
 576
 577 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 578 {
 579         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 580         /*
 581          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 582          * to represent the SCSI Target Port.
 583          */
 584         return tl_tpg->tl_tpgt;
 585 }
 586
 587 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 588 {
 589         return 1;
 590 }
 591
 592 static u32 tcm_loop_get_pr_transport_id(
 593         struct se_portal_group *se_tpg,
 594         struct se_node_acl *se_nacl,
 595         struct t10_pr_registration *pr_reg,
 596         int *format_code,
 597         unsigned char *buf)
 598 {
 599         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 600         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 601
 602         switch (tl_hba->tl_proto_id) {
 603         case SCSI_PROTOCOL_SAS:
 604                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 605                                         format_code, buf);
 606         case SCSI_PROTOCOL_FCP:
 607                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 608                                         format_code, buf);
 609         case SCSI_PROTOCOL_ISCSI:
 610                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 611                                         format_code, buf);
 612         default:
 613                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 614                         " SAS emulation\n", tl_hba->tl_proto_id);
 615                 break;
 616         }
 617
 618         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 619                         format_code, buf);
 620 }
 621
 622 static u32 tcm_loop_get_pr_transport_id_len(
 623         struct se_portal_group *se_tpg,
 624         struct se_node_acl *se_nacl,
 625         struct t10_pr_registration *pr_reg,
 626         int *format_code)
 627 {
 628         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 629         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 630
 631         switch (tl_hba->tl_proto_id) {
 632         case SCSI_PROTOCOL_SAS:
 633                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 634                                         format_code);
 635         case SCSI_PROTOCOL_FCP:
 636                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 637                                         format_code);
 638         case SCSI_PROTOCOL_ISCSI:
 639                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 640                                         format_code);
 641         default:
 642                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 643                         " SAS emulation\n", tl_hba->tl_proto_id);
 644                 break;
 645         }
 646
 647         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 648                         format_code);
 649 }
 650
 651 /*
 652  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 653  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 654  */
 655 static char *tcm_loop_parse_pr_out_transport_id(
 656         struct se_portal_group *se_tpg,
 657         const char *buf,
 658         u32 *out_tid_len,
 659         char **port_nexus_ptr)
 660 {
 661         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 662         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 663
 664         switch (tl_hba->tl_proto_id) {
 665         case SCSI_PROTOCOL_SAS:
 666                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 667                                         port_nexus_ptr);
 668         case SCSI_PROTOCOL_FCP:
 669                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 670                                         port_nexus_ptr);
 671         case SCSI_PROTOCOL_ISCSI:
 672                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 673                                         port_nexus_ptr);
 674         default:
 675                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 676                         " SAS emulation\n", tl_hba->tl_proto_id);
 677                 break;
 678         }
 679
 680         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 681                         port_nexus_ptr);
 682 }
 683
 684 /*
 685  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 686  * based upon the incoming fabric dependent SCSI Initiator Port
 687  */
 688 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 689 {
 690         return 1;
 691 }
 692
 693 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 694 {
 695         return 0;
 696 }
 697
 698 /*
 699  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 700  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 701  */
 702 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 703 {
 704         return 0;
 705 }
 706
 707 /*
 708  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 709  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 710  * It has been added here as a nop for target_fabric_tf_ops_check()
 711  */
 712 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 713 {
 714         return 0;
 715 }
 716
 717 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 718         struct se_portal_group *se_tpg)
 719 {
 720         struct tcm_loop_nacl *tl_nacl;
 721
 722         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 723         if (!tl_nacl) {
 724                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 725                 return NULL;
 726         }
 727
 728         return &tl_nacl->se_node_acl;
 729 }
 730
 731 static void tcm_loop_tpg_release_fabric_acl(
 732         struct se_portal_group *se_tpg,
 733         struct se_node_acl *se_nacl)
 734 {
 735         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 736                                 struct tcm_loop_nacl, se_node_acl);
 737
 738         kfree(tl_nacl);
 739 }
 740
 741 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 742 {
 743         return 1;
 744 }
 745
 746 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 747 {
 748         return 1;
 749 }
 750
 751 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 752 {
 753         return;
 754 }
 755
 756 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 757 {
 758         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 759                         struct tcm_loop_cmd, tl_se_cmd);
 760
 761         return tl_cmd->sc_cmd_tag;
 762 }
 763
 764 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 765 {
 766         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 767                         struct tcm_loop_cmd, tl_se_cmd);
 768
 769         return tl_cmd->sc_cmd_state;
 770 }
 771
 772 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 773 {
 774         return 0;
 775 }
 776
 777 static void tcm_loop_close_session(struct se_session *se_sess)
 778 {
 779         return;
 780 };
 781
 782 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 783 {
 784         /*
 785          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 786          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 787          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 788          * format with transport_generic_map_mem_to_cmd().
 789          *
 790          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 791          * object execution queue.
 792          */
 793         target_execute_cmd(se_cmd);
 794         return 0;
 795 }
 796
 797 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 798 {
 799         return 0;
 800 }
 801
 802 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 803 {
 804         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 805                                 struct tcm_loop_cmd, tl_se_cmd);
 806         struct scsi_cmnd *sc = tl_cmd->sc;
 807
 808         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 809                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 810
 811         sc->result = SAM_STAT_GOOD;
 812         set_host_byte(sc, DID_OK);
 813         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 814             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 815                 scsi_set_resid(sc, se_cmd->residual_count);
 816         sc->scsi_done(sc);
 817         return 0;
 818 }
 819
 820 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 821 {
 822         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 823                                 struct tcm_loop_cmd, tl_se_cmd);
 824         struct scsi_cmnd *sc = tl_cmd->sc;
 825
 826         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 827                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 828
 829         if (se_cmd->sense_buffer &&
 830            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 831             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 832
 833                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 834                                 SCSI_SENSE_BUFFERSIZE);
 835                 sc->result = SAM_STAT_CHECK_CONDITION;
 836                 set_driver_byte(sc, DRIVER_SENSE);
 837         } else
 838                 sc->result = se_cmd->scsi_status;
 839
 840         set_host_byte(sc, DID_OK);
 841         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 842             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 843                 scsi_set_resid(sc, se_cmd->residual_count);
 844         sc->scsi_done(sc);
 845         return 0;
 846 }
 847
 848 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 849 {
 850         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 851         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 852         /*
 853          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 854          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 855          */
 856         atomic_set(&tl_tmr->tmr_complete, 1);
 857         wake_up(&tl_tmr->tl_tmr_wait);
 858 }
 859
 860 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 861 {
 862         return;
 863 }
 864
 865 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 866 {
 867         switch (tl_hba->tl_proto_id) {
 868         case SCSI_PROTOCOL_SAS:
 869                 return "SAS";
 870         case SCSI_PROTOCOL_FCP:
 871                 return "FCP";
 872         case SCSI_PROTOCOL_ISCSI:
 873                 return "iSCSI";
 874         default:
 875                 break;
 876         }
 877
 878         return "Unknown";
 879 }
 880
 881 /* Start items for tcm_loop_port_cit */
 882
 883 static int tcm_loop_port_link(
 884         struct se_portal_group *se_tpg,
 885         struct se_lun *lun)
 886 {
 887         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 888                                 struct tcm_loop_tpg, tl_se_tpg);
 889         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 890
 891         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 892         /*
 893          * Add Linux/SCSI struct scsi_device by HCTL
 894          */
 895         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 896
 897         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 898         return 0;
 899 }
 900
 901 static void tcm_loop_port_unlink(
 902         struct se_portal_group *se_tpg,
 903         struct se_lun *se_lun)
 904 {
 905         struct scsi_device *sd;
 906         struct tcm_loop_hba *tl_hba;
 907         struct tcm_loop_tpg *tl_tpg;
 908
 909         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 910         tl_hba = tl_tpg->tl_hba;
 911
 912         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 913                                 se_lun->unpacked_lun);
 914         if (!sd) {
 915                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 916                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 917                 return;
 918         }
 919         /*
 920          * Remove Linux/SCSI struct scsi_device by HCTL
 921          */
 922         scsi_remove_device(sd);
 923         scsi_device_put(sd);
 924
 925         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 926
 927         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 928 }
 929
 930 /* End items for tcm_loop_port_cit */
 931
 932 /* Start items for tcm_loop_nexus_cit */
 933
 934 static int tcm_loop_make_nexus(
 935         struct tcm_loop_tpg *tl_tpg,
 936         const char *name)
 937 {
 938         struct se_portal_group *se_tpg;
 939         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 940         struct tcm_loop_nexus *tl_nexus;
 941         int ret = -ENOMEM;
 942
 943         if (tl_tpg->tl_hba->tl_nexus) {
 944                 pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
 945                 return -EEXIST;
 946         }
 947         se_tpg = &tl_tpg->tl_se_tpg;
 948
 949         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 950         if (!tl_nexus) {
 951                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 952                 return -ENOMEM;
 953         }
 954         /*
 955          * Initialize the struct se_session pointer
 956          */
 957         tl_nexus->se_sess = transport_init_session(TARGET_PROT_ALL);
 958         if (IS_ERR(tl_nexus->se_sess)) {
 959                 ret = PTR_ERR(tl_nexus->se_sess);
 960                 goto out;
 961         }
 962         /*
 963          * Since we are running in 'demo mode' this call with generate a
 964          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
 965          * Initiator port name of the passed configfs group 'name'.
 966          */
 967         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 968                                 se_tpg, (unsigned char *)name);
 969         if (!tl_nexus->se_sess->se_node_acl) {
 970                 transport_free_session(tl_nexus->se_sess);
 971                 goto out;
 972         }
 973         /*
 974          * Now, register the SAS I_T Nexus as active with the call to
 975          * transport_register_session()
 976          */
 977         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
 978                         tl_nexus->se_sess, tl_nexus);
 979         tl_tpg->tl_hba->tl_nexus = tl_nexus;
 980         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 981                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 982                 name);
 983         return 0;
 984
 985 out:
 986         kfree(tl_nexus);
 987         return ret;
 988 }
 989
 990 static int tcm_loop_drop_nexus(
 991         struct tcm_loop_tpg *tpg)
 992 {
 993         struct se_session *se_sess;
 994         struct tcm_loop_nexus *tl_nexus;
 995         struct tcm_loop_hba *tl_hba = tpg->tl_hba;
 996
 997         if (!tl_hba)
 998                 return -ENODEV;
 999
1000         tl_nexus = tl_hba->tl_nexus;
1001         if (!tl_nexus)
1002                 return -ENODEV;
1003
1004         se_sess = tl_nexus->se_sess;
1005         if (!se_sess)
1006                 return -ENODEV;
1007
1008         if (atomic_read(&tpg->tl_tpg_port_count)) {
1009                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
1010                         " active TPG port count: %d\n",
1011                         atomic_read(&tpg->tl_tpg_port_count));
1012                 return -EPERM;
1013         }
1014
1015         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1016                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1017                 tl_nexus->se_sess->se_node_acl->initiatorname);
1018         /*
1019          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1020          */
1021         transport_deregister_session(tl_nexus->se_sess);
1022         tpg->tl_hba->tl_nexus = NULL;
1023         kfree(tl_nexus);
1024         return 0;
1025 }
1026
1027 /* End items for tcm_loop_nexus_cit */
1028
1029 static ssize_t tcm_loop_tpg_show_nexus(
1030         struct se_portal_group *se_tpg,
1031         char *page)
1032 {
1033         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1034                         struct tcm_loop_tpg, tl_se_tpg);
1035         struct tcm_loop_nexus *tl_nexus;
1036         ssize_t ret;
1037
1038         tl_nexus = tl_tpg->tl_hba->tl_nexus;
1039         if (!tl_nexus)
1040                 return -ENODEV;
1041
1042         ret = snprintf(page, PAGE_SIZE, "%s\n",
1043                 tl_nexus->se_sess->se_node_acl->initiatorname);
1044
1045         return ret;
1046 }
1047
1048 static ssize_t tcm_loop_tpg_store_nexus(
1049         struct se_portal_group *se_tpg,
1050         const char *page,
1051         size_t count)
1052 {
1053         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1054                         struct tcm_loop_tpg, tl_se_tpg);
1055         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1056         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1057         int ret;
1058         /*
1059          * Shutdown the active I_T nexus if 'NULL' is passed..
1060          */
1061         if (!strncmp(page, "NULL", 4)) {
1062                 ret = tcm_loop_drop_nexus(tl_tpg);
1063                 return (!ret) ? count : ret;
1064         }
1065         /*
1066          * Otherwise make sure the passed virtual Initiator port WWN matches
1067          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1068          * tcm_loop_make_nexus()
1069          */
1070         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1071                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1072                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1073                 return -EINVAL;
1074         }
1075         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1076
1077         ptr = strstr(i_port, "naa.");
1078         if (ptr) {
1079                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1080                         pr_err("Passed SAS Initiator Port %s does not"
1081                                 " match target port protoid: %s\n", i_port,
1082                                 tcm_loop_dump_proto_id(tl_hba));
1083                         return -EINVAL;
1084                 }
1085                 port_ptr = &i_port[0];
1086                 goto check_newline;
1087         }
1088         ptr = strstr(i_port, "fc.");
1089         if (ptr) {
1090                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1091                         pr_err("Passed FCP Initiator Port %s does not"
1092                                 " match target port protoid: %s\n", i_port,
1093                                 tcm_loop_dump_proto_id(tl_hba));
1094                         return -EINVAL;
1095                 }
1096                 port_ptr = &i_port[3]; /* Skip over "fc." */
1097                 goto check_newline;
1098         }
1099         ptr = strstr(i_port, "iqn.");
1100         if (ptr) {
1101                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1102                         pr_err("Passed iSCSI Initiator Port %s does not"
1103                                 " match target port protoid: %s\n", i_port,
1104                                 tcm_loop_dump_proto_id(tl_hba));
1105                         return -EINVAL;
1106                 }
1107                 port_ptr = &i_port[0];
1108                 goto check_newline;
1109         }
1110         pr_err("Unable to locate prefix for emulated Initiator Port:"
1111                         " %s\n", i_port);
1112         return -EINVAL;
1113         /*
1114          * Clear any trailing newline for the NAA WWN
1115          */
1116 check_newline:
1117         if (i_port[strlen(i_port)-1] == '\n')
1118                 i_port[strlen(i_port)-1] = '\0';
1119
1120         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1121         if (ret < 0)
1122                 return ret;
1123
1124         return count;
1125 }
1126
1127 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1128
1129 static ssize_t tcm_loop_tpg_show_transport_status(
1130         struct se_portal_group *se_tpg,
1131         char *page)
1132 {
1133         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1134                         struct tcm_loop_tpg, tl_se_tpg);
1135         const char *status = NULL;
1136         ssize_t ret = -EINVAL;
1137
1138         switch (tl_tpg->tl_transport_status) {
1139         case TCM_TRANSPORT_ONLINE:
1140                 status = "online";
1141                 break;
1142         case TCM_TRANSPORT_OFFLINE:
1143                 status = "offline";
1144                 break;
1145         default:
1146                 break;
1147         }
1148
1149         if (status)
1150                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1151
1152         return ret;
1153 }
1154
1155 static ssize_t tcm_loop_tpg_store_transport_status(
1156         struct se_portal_group *se_tpg,
1157         const char *page,
1158         size_t count)
1159 {
1160         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1161                         struct tcm_loop_tpg, tl_se_tpg);
1162
1163         if (!strncmp(page, "online", 6)) {
1164                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1165                 return count;
1166         }
1167         if (!strncmp(page, "offline", 7)) {
1168                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1169                 return count;
1170         }
1171         return -EINVAL;
1172 }
1173
1174 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1175
1176 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1177         &tcm_loop_tpg_nexus.attr,
1178         &tcm_loop_tpg_transport_status.attr,
1179         NULL,
1180 };
1181
1182 /* Start items for tcm_loop_naa_cit */
1183
1184 static struct se_portal_group *tcm_loop_make_naa_tpg(
1185         struct se_wwn *wwn,
1186         struct config_group *group,
1187         const char *name)
1188 {
1189         struct tcm_loop_hba *tl_hba = container_of(wwn,
1190                         struct tcm_loop_hba, tl_hba_wwn);
1191         struct tcm_loop_tpg *tl_tpg;
1192         char *tpgt_str, *end_ptr;
1193         int ret;
1194         unsigned short int tpgt;
1195
1196         tpgt_str = strstr(name, "tpgt_");
1197         if (!tpgt_str) {
1198                 pr_err("Unable to locate \"tpgt_#\" directory"
1199                                 " group\n");
1200                 return ERR_PTR(-EINVAL);
1201         }
1202         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1203         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1204
1205         if (tpgt >= TL_TPGS_PER_HBA) {
1206                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1207                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1208                 return ERR_PTR(-EINVAL);
1209         }
1210         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1211         tl_tpg->tl_hba = tl_hba;
1212         tl_tpg->tl_tpgt = tpgt;
1213         /*
1214          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1215          */
1216         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1217                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1218                         TRANSPORT_TPG_TYPE_NORMAL);
1219         if (ret < 0)
1220                 return ERR_PTR(-ENOMEM);
1221
1222         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1223                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1224                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1225
1226         return &tl_tpg->tl_se_tpg;
1227 }
1228
1229 static void tcm_loop_drop_naa_tpg(
1230         struct se_portal_group *se_tpg)
1231 {
1232         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1233         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1234                                 struct tcm_loop_tpg, tl_se_tpg);
1235         struct tcm_loop_hba *tl_hba;
1236         unsigned short tpgt;
1237
1238         tl_hba = tl_tpg->tl_hba;
1239         tpgt = tl_tpg->tl_tpgt;
1240         /*
1241          * Release the I_T Nexus for the Virtual SAS link if present
1242          */
1243         tcm_loop_drop_nexus(tl_tpg);
1244         /*
1245          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1246          */
1247         core_tpg_deregister(se_tpg);
1248
1249         tl_tpg->tl_hba = NULL;
1250         tl_tpg->tl_tpgt = 0;
1251
1252         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1253                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1254                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1255 }
1256
1257 /* End items for tcm_loop_naa_cit */
1258
1259 /* Start items for tcm_loop_cit */
1260
1261 static struct se_wwn *tcm_loop_make_scsi_hba(
1262         struct target_fabric_configfs *tf,
1263         struct config_group *group,
1264         const char *name)
1265 {
1266         struct tcm_loop_hba *tl_hba;
1267         struct Scsi_Host *sh;
1268         char *ptr;
1269         int ret, off = 0;
1270
1271         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1272         if (!tl_hba) {
1273                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1274                 return ERR_PTR(-ENOMEM);
1275         }
1276         /*
1277          * Determine the emulated Protocol Identifier and Target Port Name
1278          * based on the incoming configfs directory name.
1279          */
1280         ptr = strstr(name, "naa.");
1281         if (ptr) {
1282                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1283                 goto check_len;
1284         }
1285         ptr = strstr(name, "fc.");
1286         if (ptr) {
1287                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1288                 off = 3; /* Skip over "fc." */
1289                 goto check_len;
1290         }
1291         ptr = strstr(name, "iqn.");
1292         if (!ptr) {
1293                 pr_err("Unable to locate prefix for emulated Target "
1294                                 "Port: %s\n", name);
1295                 ret = -EINVAL;
1296                 goto out;
1297         }
1298         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1299
1300 check_len:
1301         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1302                 pr_err("Emulated NAA %s Address: %s, exceeds"
1303                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1304                         TL_WWN_ADDR_LEN);
1305                 ret = -EINVAL;
1306                 goto out;
1307         }
1308         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1309
1310         /*
1311          * Call device_register(tl_hba->dev) to register the emulated
1312          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1313          * device_register() callbacks in tcm_loop_driver_probe()
1314          */
1315         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1316         if (ret)
1317                 goto out;
1318
1319         sh = tl_hba->sh;
1320         tcm_loop_hba_no_cnt++;
1321         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1322                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1323                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1324
1325         return &tl_hba->tl_hba_wwn;
1326 out:
1327         kfree(tl_hba);
1328         return ERR_PTR(ret);
1329 }
1330
1331 static void tcm_loop_drop_scsi_hba(
1332         struct se_wwn *wwn)
1333 {
1334         struct tcm_loop_hba *tl_hba = container_of(wwn,
1335                                 struct tcm_loop_hba, tl_hba_wwn);
1336
1337         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1338                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1339                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1340         /*
1341          * Call device_unregister() on the original tl_hba->dev.
1342          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1343          * release *tl_hba;
1344          */
1345         device_unregister(&tl_hba->dev);
1346 }
1347
1348 /* Start items for tcm_loop_cit */
1349 static ssize_t tcm_loop_wwn_show_attr_version(
1350         struct target_fabric_configfs *tf,
1351         char *page)
1352 {
1353         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1354 }
1355
1356 TF_WWN_ATTR_RO(tcm_loop, version);
1357
1358 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1359         &tcm_loop_wwn_version.attr,
1360         NULL,
1361 };
1362
1363 /* End items for tcm_loop_cit */
1364
1365 static int tcm_loop_register_configfs(void)
1366 {
1367         struct target_fabric_configfs *fabric;
1368         int ret;
1369         /*
1370          * Set the TCM Loop HBA counter to zero
1371          */
1372         tcm_loop_hba_no_cnt = 0;
1373         /*
1374          * Register the top level struct config_item_type with TCM core
1375          */
1376         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1377         if (IS_ERR(fabric)) {
1378                 pr_err("tcm_loop_register_configfs() failed!\n");
1379                 return PTR_ERR(fabric);
1380         }
1381         /*
1382          * Setup the fabric API of function pointers used by target_core_mod
1383          */
1384         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1385         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1386         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1387         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1388         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1389         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1390         fabric->tf_ops.tpg_get_pr_transport_id_len =
1391                                         &tcm_loop_get_pr_transport_id_len;
1392         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1393                                         &tcm_loop_parse_pr_out_transport_id;
1394         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1395         fabric->tf_ops.tpg_check_demo_mode_cache =
1396                                         &tcm_loop_check_demo_mode_cache;
1397         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1398                                         &tcm_loop_check_demo_mode_write_protect;
1399         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1400                                         &tcm_loop_check_prod_mode_write_protect;
1401         /*
1402          * The TCM loopback fabric module runs in demo-mode to a local
1403          * virtual SCSI device, so fabric dependent initator ACLs are
1404          * not required.
1405          */
1406         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1407         fabric->tf_ops.tpg_release_fabric_acl =
1408                                         &tcm_loop_tpg_release_fabric_acl;
1409         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1410         /*
1411          * Used for setting up remaining TCM resources in process context
1412          */
1413         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1414         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1415         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1416         fabric->tf_ops.close_session = &tcm_loop_close_session;
1417         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1418         fabric->tf_ops.sess_get_initiator_sid = NULL;
1419         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1420         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1421         /*
1422          * Not used for TCM loopback
1423          */
1424         fabric->tf_ops.set_default_node_attributes =
1425                                         &tcm_loop_set_default_node_attributes;
1426         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1427         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1428         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1429         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1430         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1431         fabric->tf_ops.aborted_task = &tcm_loop_aborted_task;
1432
1433         /*
1434          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1435          */
1436         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1437         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1438         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1439         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1440         /*
1441          * fabric_post_link() and fabric_pre_unlink() are used for
1442          * registration and release of TCM Loop Virtual SCSI LUNs.
1443          */
1444         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1445         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1446         fabric->tf_ops.fabric_make_np = NULL;
1447         fabric->tf_ops.fabric_drop_np = NULL;
1448         /*
1449          * Setup default attribute lists for various fabric->tf_cit_tmpl
1450          */
1451         fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1452         fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1453         fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
1454         fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
1455         fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
1456         /*
1457          * Once fabric->tf_ops has been setup, now register the fabric for
1458          * use within TCM
1459          */
1460         ret = target_fabric_configfs_register(fabric);
1461         if (ret < 0) {
1462                 pr_err("target_fabric_configfs_register() for"
1463                                 " TCM_Loop failed!\n");
1464                 target_fabric_configfs_free(fabric);
1465                 return -1;
1466         }
1467         /*
1468          * Setup our local pointer to *fabric.
1469          */
1470         tcm_loop_fabric_configfs = fabric;
1471         pr_debug("TCM_LOOP[0] - Set fabric ->"
1472                         " tcm_loop_fabric_configfs\n");
1473         return 0;
1474 }
1475
1476 static void tcm_loop_deregister_configfs(void)
1477 {
1478         if (!tcm_loop_fabric_configfs)
1479                 return;
1480
1481         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1482         tcm_loop_fabric_configfs = NULL;
1483         pr_debug("TCM_LOOP[0] - Cleared"
1484                                 " tcm_loop_fabric_configfs\n");
1485 }
1486
1487 static int __init tcm_loop_fabric_init(void)
1488 {
1489         int ret = -ENOMEM;
1490
1491         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1492         if (!tcm_loop_workqueue)
1493                 goto out;
1494
1495         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1496                                 sizeof(struct tcm_loop_cmd),
1497                                 __alignof__(struct tcm_loop_cmd),
1498                                 0, NULL);
1499         if (!tcm_loop_cmd_cache) {
1500                 pr_debug("kmem_cache_create() for"
1501                         " tcm_loop_cmd_cache failed\n");
1502                 goto out_destroy_workqueue;
1503         }
1504
1505         ret = tcm_loop_alloc_core_bus();
1506         if (ret)
1507                 goto out_destroy_cache;
1508
1509         ret = tcm_loop_register_configfs();
1510         if (ret)
1511                 goto out_release_core_bus;
1512
1513         return 0;
1514
1515 out_release_core_bus:
1516         tcm_loop_release_core_bus();
1517 out_destroy_cache:
1518         kmem_cache_destroy(tcm_loop_cmd_cache);
1519 out_destroy_workqueue:
1520         destroy_workqueue(tcm_loop_workqueue);
1521 out:
1522         return ret;
1523 }
1524
1525 static void __exit tcm_loop_fabric_exit(void)
1526 {
1527         tcm_loop_deregister_configfs();
1528         tcm_loop_release_core_bus();
1529         kmem_cache_destroy(tcm_loop_cmd_cache);
1530         destroy_workqueue(tcm_loop_workqueue);
1531 }
1532
1533 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1534 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1535 MODULE_LICENSE("GPL");
1536 module_init(tcm_loop_fabric_init);
1537 module_exit(tcm_loop_fabric_exit);