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 static const struct target_core_fabric_ops loop_ops;
  45
  46 static struct workqueue_struct *tcm_loop_workqueue;
  47 static struct kmem_cache *tcm_loop_cmd_cache;
  48
  49 static int tcm_loop_hba_no_cnt;
  50
  51 static int tcm_loop_queue_status(struct se_cmd *se_cmd);
  52
  53 /*
  54  * Called from struct target_core_fabric_ops->check_stop_free()
  55  */
  56 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  57 {
  58         /*
  59          * Do not release struct se_cmd's containing a valid TMR
  60          * pointer.  These will be released directly in tcm_loop_device_reset()
  61          * with transport_generic_free_cmd().
  62          */
  63         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
  64                 return 0;
  65         /*
  66          * Release the struct se_cmd, which will make a callback to release
  67          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
  68          */
  69         transport_generic_free_cmd(se_cmd, 0);
  70         return 1;
  71 }
  72
  73 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  74 {
  75         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  76                                 struct tcm_loop_cmd, tl_se_cmd);
  77
  78         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  79 }
  80
  81 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  82 {
  83         seq_printf(m, "tcm_loop_proc_info()\n");
  84         return 0;
  85 }
  86
  87 static int tcm_loop_driver_probe(struct device *);
  88 static int tcm_loop_driver_remove(struct device *);
  89
  90 static int pseudo_lld_bus_match(struct device *dev,
  91                                 struct device_driver *dev_driver)
  92 {
  93         return 1;
  94 }
  95
  96 static struct bus_type tcm_loop_lld_bus = {
  97         .name                   = "tcm_loop_bus",
  98         .match                  = pseudo_lld_bus_match,
  99         .probe                  = tcm_loop_driver_probe,
 100         .remove                 = tcm_loop_driver_remove,
 101 };
 102
 103 static struct device_driver tcm_loop_driverfs = {
 104         .name                   = "tcm_loop",
 105         .bus                    = &tcm_loop_lld_bus,
 106 };
 107 /*
 108  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 109  */
 110 static struct device *tcm_loop_primary;
 111
 112 static void tcm_loop_submission_work(struct work_struct *work)
 113 {
 114         struct tcm_loop_cmd *tl_cmd =
 115                 container_of(work, struct tcm_loop_cmd, work);
 116         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 117         struct scsi_cmnd *sc = tl_cmd->sc;
 118         struct tcm_loop_nexus *tl_nexus;
 119         struct tcm_loop_hba *tl_hba;
 120         struct tcm_loop_tpg *tl_tpg;
 121         struct scatterlist *sgl_bidi = NULL;
 122         u32 sgl_bidi_count = 0, transfer_length;
 123         int rc;
 124
 125         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 126         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 127
 128         /*
 129          * Ensure that this tl_tpg reference from the incoming sc->device->id
 130          * has already been configured via tcm_loop_make_naa_tpg().
 131          */
 132         if (!tl_tpg->tl_hba) {
 133                 set_host_byte(sc, DID_NO_CONNECT);
 134                 goto out_done;
 135         }
 136         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 137                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 138                 goto out_done;
 139         }
 140         tl_nexus = tl_tpg->tl_nexus;
 141         if (!tl_nexus) {
 142                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
 143                                 " does not exist\n");
 144                 set_host_byte(sc, DID_ERROR);
 145                 goto out_done;
 146         }
 147         if (scsi_bidi_cmnd(sc)) {
 148                 struct scsi_data_buffer *sdb = scsi_in(sc);
 149
 150                 sgl_bidi = sdb->table.sgl;
 151                 sgl_bidi_count = sdb->table.nents;
 152                 se_cmd->se_cmd_flags |= SCF_BIDI;
 153
 154         }
 155
 156         transfer_length = scsi_transfer_length(sc);
 157         if (!scsi_prot_sg_count(sc) &&
 158             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 159                 se_cmd->prot_pto = true;
 160                 /*
 161                  * loopback transport doesn't support
 162                  * WRITE_GENERATE, READ_STRIP protection
 163                  * information operations, go ahead unprotected.
 164                  */
 165                 transfer_length = scsi_bufflen(sc);
 166         }
 167
 168         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 169                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 170                         transfer_length, TCM_SIMPLE_TAG,
 171                         sc->sc_data_direction, 0,
 172                         scsi_sglist(sc), scsi_sg_count(sc),
 173                         sgl_bidi, sgl_bidi_count,
 174                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 175         if (rc < 0) {
 176                 set_host_byte(sc, DID_NO_CONNECT);
 177                 goto out_done;
 178         }
 179         return;
 180
 181 out_done:
 182         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 183         sc->scsi_done(sc);
 184         return;
 185 }
 186
 187 /*
 188  * ->queuecommand can be and usually is called from interrupt context, so
 189  * defer the actual submission to a workqueue.
 190  */
 191 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 192 {
 193         struct tcm_loop_cmd *tl_cmd;
 194
 195         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
 196                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 197                 sc->device->id, sc->device->channel, sc->device->lun,
 198                 sc->cmnd[0], scsi_bufflen(sc));
 199
 200         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 201         if (!tl_cmd) {
 202                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
 203                 set_host_byte(sc, DID_ERROR);
 204                 sc->scsi_done(sc);
 205                 return 0;
 206         }
 207
 208         tl_cmd->sc = sc;
 209         tl_cmd->sc_cmd_tag = sc->request->tag;
 210         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 211         queue_work(tcm_loop_workqueue, &tl_cmd->work);
 212         return 0;
 213 }
 214
 215 /*
 216  * Called from SCSI EH process context to issue a LUN_RESET TMR
 217  * to struct scsi_device
 218  */
 219 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 220                               int lun, int task, enum tcm_tmreq_table tmr)
 221 {
 222         struct se_cmd *se_cmd = NULL;
 223         struct se_session *se_sess;
 224         struct se_portal_group *se_tpg;
 225         struct tcm_loop_nexus *tl_nexus;
 226         struct tcm_loop_cmd *tl_cmd = NULL;
 227         struct tcm_loop_tmr *tl_tmr = NULL;
 228         int ret = TMR_FUNCTION_FAILED, rc;
 229
 230         /*
 231          * Locate the tl_nexus and se_sess pointers
 232          */
 233         tl_nexus = tl_tpg->tl_nexus;
 234         if (!tl_nexus) {
 235                 pr_err("Unable to perform device reset without"
 236                                 " active I_T Nexus\n");
 237                 return ret;
 238         }
 239
 240         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 241         if (!tl_cmd) {
 242                 pr_err("Unable to allocate memory for tl_cmd\n");
 243                 return ret;
 244         }
 245
 246         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 247         if (!tl_tmr) {
 248                 pr_err("Unable to allocate memory for tl_tmr\n");
 249                 goto release;
 250         }
 251         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 252
 253         se_cmd = &tl_cmd->tl_se_cmd;
 254         se_tpg = &tl_tpg->tl_se_tpg;
 255         se_sess = tl_tpg->tl_nexus->se_sess;
 256         /*
 257          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 258          */
 259         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 260                                 DMA_NONE, TCM_SIMPLE_TAG,
 261                                 &tl_cmd->tl_sense_buf[0]);
 262
 263         rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
 264         if (rc < 0)
 265                 goto release;
 266
 267         if (tmr == TMR_ABORT_TASK)
 268                 se_cmd->se_tmr_req->ref_task_tag = task;
 269
 270         /*
 271          * Locate the underlying TCM struct se_lun
 272          */
 273         if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
 274                 ret = TMR_LUN_DOES_NOT_EXIST;
 275                 goto release;
 276         }
 277         /*
 278          * Queue the TMR to TCM Core and sleep waiting for
 279          * tcm_loop_queue_tm_rsp() to wake us up.
 280          */
 281         transport_generic_handle_tmr(se_cmd);
 282         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 283         /*
 284          * The TMR LUN_RESET has completed, check the response status and
 285          * then release allocations.
 286          */
 287         ret = se_cmd->se_tmr_req->response;
 288 release:
 289         if (se_cmd)
 290                 transport_generic_free_cmd(se_cmd, 1);
 291         else
 292                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 293         kfree(tl_tmr);
 294         return ret;
 295 }
 296
 297 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 298 {
 299         struct tcm_loop_hba *tl_hba;
 300         struct tcm_loop_tpg *tl_tpg;
 301         int ret = FAILED;
 302
 303         /*
 304          * Locate the tcm_loop_hba_t pointer
 305          */
 306         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 307         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 308         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 309                                  sc->request->tag, TMR_ABORT_TASK);
 310         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 311 }
 312
 313 /*
 314  * Called from SCSI EH process context to issue a LUN_RESET TMR
 315  * to struct scsi_device
 316  */
 317 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 318 {
 319         struct tcm_loop_hba *tl_hba;
 320         struct tcm_loop_tpg *tl_tpg;
 321         int ret = FAILED;
 322
 323         /*
 324          * Locate the tcm_loop_hba_t pointer
 325          */
 326         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 327         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 328
 329         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 330                                  0, TMR_LUN_RESET);
 331         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 332 }
 333
 334 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 335 {
 336         struct tcm_loop_hba *tl_hba;
 337         struct tcm_loop_tpg *tl_tpg;
 338
 339         /*
 340          * Locate the tcm_loop_hba_t pointer
 341          */
 342         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 343         if (!tl_hba) {
 344                 pr_err("Unable to perform device reset without"
 345                                 " active I_T Nexus\n");
 346                 return FAILED;
 347         }
 348         /*
 349          * Locate the tl_tpg pointer from TargetID in sc->device->id
 350          */
 351         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 352         if (tl_tpg) {
 353                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 354                 return SUCCESS;
 355         }
 356         return FAILED;
 357 }
 358
 359 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 360 {
 361         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 362         return 0;
 363 }
 364
 365 static struct scsi_host_template tcm_loop_driver_template = {
 366         .show_info              = tcm_loop_show_info,
 367         .proc_name              = "tcm_loopback",
 368         .name                   = "TCM_Loopback",
 369         .queuecommand           = tcm_loop_queuecommand,
 370         .change_queue_depth     = scsi_change_queue_depth,
 371         .eh_abort_handler = tcm_loop_abort_task,
 372         .eh_device_reset_handler = tcm_loop_device_reset,
 373         .eh_target_reset_handler = tcm_loop_target_reset,
 374         .can_queue              = 1024,
 375         .this_id                = -1,
 376         .sg_tablesize           = 256,
 377         .cmd_per_lun            = 1024,
 378         .max_sectors            = 0xFFFF,
 379         .use_clustering         = DISABLE_CLUSTERING,
 380         .slave_alloc            = tcm_loop_slave_alloc,
 381         .module                 = THIS_MODULE,
 382         .use_blk_tags           = 1,
 383         .track_queue_depth      = 1,
 384 };
 385
 386 static int tcm_loop_driver_probe(struct device *dev)
 387 {
 388         struct tcm_loop_hba *tl_hba;
 389         struct Scsi_Host *sh;
 390         int error, host_prot;
 391
 392         tl_hba = to_tcm_loop_hba(dev);
 393
 394         sh = scsi_host_alloc(&tcm_loop_driver_template,
 395                         sizeof(struct tcm_loop_hba));
 396         if (!sh) {
 397                 pr_err("Unable to allocate struct scsi_host\n");
 398                 return -ENODEV;
 399         }
 400         tl_hba->sh = sh;
 401
 402         /*
 403          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 404          */
 405         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 406         /*
 407          * Setup single ID, Channel and LUN for now..
 408          */
 409         sh->max_id = 2;
 410         sh->max_lun = 0;
 411         sh->max_channel = 0;
 412         sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 413
 414         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 415                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 416                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 417
 418         scsi_host_set_prot(sh, host_prot);
 419         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 420
 421         error = scsi_add_host(sh, &tl_hba->dev);
 422         if (error) {
 423                 pr_err("%s: scsi_add_host failed\n", __func__);
 424                 scsi_host_put(sh);
 425                 return -ENODEV;
 426         }
 427         return 0;
 428 }
 429
 430 static int tcm_loop_driver_remove(struct device *dev)
 431 {
 432         struct tcm_loop_hba *tl_hba;
 433         struct Scsi_Host *sh;
 434
 435         tl_hba = to_tcm_loop_hba(dev);
 436         sh = tl_hba->sh;
 437
 438         scsi_remove_host(sh);
 439         scsi_host_put(sh);
 440         return 0;
 441 }
 442
 443 static void tcm_loop_release_adapter(struct device *dev)
 444 {
 445         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 446
 447         kfree(tl_hba);
 448 }
 449
 450 /*
 451  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 452  */
 453 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 454 {
 455         int ret;
 456
 457         tl_hba->dev.bus = &tcm_loop_lld_bus;
 458         tl_hba->dev.parent = tcm_loop_primary;
 459         tl_hba->dev.release = &tcm_loop_release_adapter;
 460         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 461
 462         ret = device_register(&tl_hba->dev);
 463         if (ret) {
 464                 pr_err("device_register() failed for"
 465                                 " tl_hba->dev: %d\n", ret);
 466                 return -ENODEV;
 467         }
 468
 469         return 0;
 470 }
 471
 472 /*
 473  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 474  * tcm_loop SCSI bus.
 475  */
 476 static int tcm_loop_alloc_core_bus(void)
 477 {
 478         int ret;
 479
 480         tcm_loop_primary = root_device_register("tcm_loop_0");
 481         if (IS_ERR(tcm_loop_primary)) {
 482                 pr_err("Unable to allocate tcm_loop_primary\n");
 483                 return PTR_ERR(tcm_loop_primary);
 484         }
 485
 486         ret = bus_register(&tcm_loop_lld_bus);
 487         if (ret) {
 488                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 489                 goto dev_unreg;
 490         }
 491
 492         ret = driver_register(&tcm_loop_driverfs);
 493         if (ret) {
 494                 pr_err("driver_register() failed for"
 495                                 "tcm_loop_driverfs\n");
 496                 goto bus_unreg;
 497         }
 498
 499         pr_debug("Initialized TCM Loop Core Bus\n");
 500         return ret;
 501
 502 bus_unreg:
 503         bus_unregister(&tcm_loop_lld_bus);
 504 dev_unreg:
 505         root_device_unregister(tcm_loop_primary);
 506         return ret;
 507 }
 508
 509 static void tcm_loop_release_core_bus(void)
 510 {
 511         driver_unregister(&tcm_loop_driverfs);
 512         bus_unregister(&tcm_loop_lld_bus);
 513         root_device_unregister(tcm_loop_primary);
 514
 515         pr_debug("Releasing TCM Loop Core BUS\n");
 516 }
 517
 518 static char *tcm_loop_get_fabric_name(void)
 519 {
 520         return "loopback";
 521 }
 522
 523 static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
 524 {
 525         return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 526 }
 527
 528 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 529 {
 530         struct tcm_loop_hba *tl_hba = tl_tpg(se_tpg)->tl_hba;
 531         /*
 532          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 533          * time based on the protocol dependent prefix of the passed configfs group.
 534          *
 535          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 536          * ProtocolID using target_core_fabric_lib.c symbols.
 537          */
 538         switch (tl_hba->tl_proto_id) {
 539         case SCSI_PROTOCOL_SAS:
 540                 return sas_get_fabric_proto_ident(se_tpg);
 541         case SCSI_PROTOCOL_FCP:
 542                 return fc_get_fabric_proto_ident(se_tpg);
 543         case SCSI_PROTOCOL_ISCSI:
 544                 return iscsi_get_fabric_proto_ident(se_tpg);
 545         default:
 546                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 547                         " SAS emulation\n", tl_hba->tl_proto_id);
 548                 break;
 549         }
 550
 551         return sas_get_fabric_proto_ident(se_tpg);
 552 }
 553
 554 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 555 {
 556         /*
 557          * Return the passed NAA identifier for the SAS Target Port
 558          */
 559         return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
 560 }
 561
 562 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 563 {
 564         /*
 565          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 566          * to represent the SCSI Target Port.
 567          */
 568         return tl_tpg(se_tpg)->tl_tpgt;
 569 }
 570
 571 static u32 tcm_loop_get_pr_transport_id(
 572         struct se_portal_group *se_tpg,
 573         struct se_node_acl *se_nacl,
 574         struct t10_pr_registration *pr_reg,
 575         int *format_code,
 576         unsigned char *buf)
 577 {
 578         struct tcm_loop_hba *tl_hba = tl_tpg(se_tpg)->tl_hba;
 579
 580         switch (tl_hba->tl_proto_id) {
 581         case SCSI_PROTOCOL_SAS:
 582                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 583                                         format_code, buf);
 584         case SCSI_PROTOCOL_FCP:
 585                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 586                                         format_code, buf);
 587         case SCSI_PROTOCOL_ISCSI:
 588                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 589                                         format_code, buf);
 590         default:
 591                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 592                         " SAS emulation\n", tl_hba->tl_proto_id);
 593                 break;
 594         }
 595
 596         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 597                         format_code, buf);
 598 }
 599
 600 static u32 tcm_loop_get_pr_transport_id_len(
 601         struct se_portal_group *se_tpg,
 602         struct se_node_acl *se_nacl,
 603         struct t10_pr_registration *pr_reg,
 604         int *format_code)
 605 {
 606         struct tcm_loop_hba *tl_hba = tl_tpg(se_tpg)->tl_hba;
 607
 608         switch (tl_hba->tl_proto_id) {
 609         case SCSI_PROTOCOL_SAS:
 610                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 611                                         format_code);
 612         case SCSI_PROTOCOL_FCP:
 613                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 614                                         format_code);
 615         case SCSI_PROTOCOL_ISCSI:
 616                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 617                                         format_code);
 618         default:
 619                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 620                         " SAS emulation\n", tl_hba->tl_proto_id);
 621                 break;
 622         }
 623
 624         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 625                         format_code);
 626 }
 627
 628 /*
 629  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 630  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 631  */
 632 static char *tcm_loop_parse_pr_out_transport_id(
 633         struct se_portal_group *se_tpg,
 634         const char *buf,
 635         u32 *out_tid_len,
 636         char **port_nexus_ptr)
 637 {
 638         struct tcm_loop_hba *tl_hba = tl_tpg(se_tpg)->tl_hba;
 639
 640         switch (tl_hba->tl_proto_id) {
 641         case SCSI_PROTOCOL_SAS:
 642                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 643                                         port_nexus_ptr);
 644         case SCSI_PROTOCOL_FCP:
 645                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 646                                         port_nexus_ptr);
 647         case SCSI_PROTOCOL_ISCSI:
 648                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 649                                         port_nexus_ptr);
 650         default:
 651                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 652                         " SAS emulation\n", tl_hba->tl_proto_id);
 653                 break;
 654         }
 655
 656         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 657                         port_nexus_ptr);
 658 }
 659
 660 /*
 661  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 662  * based upon the incoming fabric dependent SCSI Initiator Port
 663  */
 664 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 665 {
 666         return 1;
 667 }
 668
 669 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 670 {
 671         return 0;
 672 }
 673
 674 /*
 675  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 676  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 677  */
 678 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 679 {
 680         return 0;
 681 }
 682
 683 /*
 684  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 685  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 686  * It has been added here as a nop for target_fabric_tf_ops_check()
 687  */
 688 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 689 {
 690         return 0;
 691 }
 692
 693 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
 694 {
 695         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 696                                                    tl_se_tpg);
 697         return tl_tpg->tl_fabric_prot_type;
 698 }
 699
 700 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 701 {
 702         return 1;
 703 }
 704
 705 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 706 {
 707         return 1;
 708 }
 709
 710 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 711 {
 712         return;
 713 }
 714
 715 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 716 {
 717         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 718                         struct tcm_loop_cmd, tl_se_cmd);
 719
 720         return tl_cmd->sc_cmd_tag;
 721 }
 722
 723 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 724 {
 725         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 726                         struct tcm_loop_cmd, tl_se_cmd);
 727
 728         return tl_cmd->sc_cmd_state;
 729 }
 730
 731 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 732 {
 733         return 0;
 734 }
 735
 736 static void tcm_loop_close_session(struct se_session *se_sess)
 737 {
 738         return;
 739 };
 740
 741 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 742 {
 743         /*
 744          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 745          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 746          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 747          * format with transport_generic_map_mem_to_cmd().
 748          *
 749          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 750          * object execution queue.
 751          */
 752         target_execute_cmd(se_cmd);
 753         return 0;
 754 }
 755
 756 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 757 {
 758         return 0;
 759 }
 760
 761 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 762 {
 763         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 764                                 struct tcm_loop_cmd, tl_se_cmd);
 765         struct scsi_cmnd *sc = tl_cmd->sc;
 766
 767         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 768                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 769
 770         sc->result = SAM_STAT_GOOD;
 771         set_host_byte(sc, DID_OK);
 772         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 773             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 774                 scsi_set_resid(sc, se_cmd->residual_count);
 775         sc->scsi_done(sc);
 776         return 0;
 777 }
 778
 779 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 780 {
 781         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 782                                 struct tcm_loop_cmd, tl_se_cmd);
 783         struct scsi_cmnd *sc = tl_cmd->sc;
 784
 785         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 786                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 787
 788         if (se_cmd->sense_buffer &&
 789            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 790             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 791
 792                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 793                                 SCSI_SENSE_BUFFERSIZE);
 794                 sc->result = SAM_STAT_CHECK_CONDITION;
 795                 set_driver_byte(sc, DRIVER_SENSE);
 796         } else
 797                 sc->result = se_cmd->scsi_status;
 798
 799         set_host_byte(sc, DID_OK);
 800         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 801             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 802                 scsi_set_resid(sc, se_cmd->residual_count);
 803         sc->scsi_done(sc);
 804         return 0;
 805 }
 806
 807 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 808 {
 809         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 810         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 811         /*
 812          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 813          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 814          */
 815         atomic_set(&tl_tmr->tmr_complete, 1);
 816         wake_up(&tl_tmr->tl_tmr_wait);
 817 }
 818
 819 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 820 {
 821         return;
 822 }
 823
 824 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 825 {
 826         switch (tl_hba->tl_proto_id) {
 827         case SCSI_PROTOCOL_SAS:
 828                 return "SAS";
 829         case SCSI_PROTOCOL_FCP:
 830                 return "FCP";
 831         case SCSI_PROTOCOL_ISCSI:
 832                 return "iSCSI";
 833         default:
 834                 break;
 835         }
 836
 837         return "Unknown";
 838 }
 839
 840 /* Start items for tcm_loop_port_cit */
 841
 842 static int tcm_loop_port_link(
 843         struct se_portal_group *se_tpg,
 844         struct se_lun *lun)
 845 {
 846         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 847                                 struct tcm_loop_tpg, tl_se_tpg);
 848         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 849
 850         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 851         /*
 852          * Add Linux/SCSI struct scsi_device by HCTL
 853          */
 854         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 855
 856         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 857         return 0;
 858 }
 859
 860 static void tcm_loop_port_unlink(
 861         struct se_portal_group *se_tpg,
 862         struct se_lun *se_lun)
 863 {
 864         struct scsi_device *sd;
 865         struct tcm_loop_hba *tl_hba;
 866         struct tcm_loop_tpg *tl_tpg;
 867
 868         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 869         tl_hba = tl_tpg->tl_hba;
 870
 871         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 872                                 se_lun->unpacked_lun);
 873         if (!sd) {
 874                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 875                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 876                 return;
 877         }
 878         /*
 879          * Remove Linux/SCSI struct scsi_device by HCTL
 880          */
 881         scsi_remove_device(sd);
 882         scsi_device_put(sd);
 883
 884         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 885
 886         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 887 }
 888
 889 /* End items for tcm_loop_port_cit */
 890
 891 static ssize_t tcm_loop_tpg_attrib_show_fabric_prot_type(
 892         struct se_portal_group *se_tpg,
 893         char *page)
 894 {
 895         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 896                                                    tl_se_tpg);
 897
 898         return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
 899 }
 900
 901 static ssize_t tcm_loop_tpg_attrib_store_fabric_prot_type(
 902         struct se_portal_group *se_tpg,
 903         const char *page,
 904         size_t count)
 905 {
 906         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 907                                                    tl_se_tpg);
 908         unsigned long val;
 909         int ret = kstrtoul(page, 0, &val);
 910
 911         if (ret) {
 912                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
 913                 return ret;
 914         }
 915         if (val != 0 && val != 1 && val != 3) {
 916                 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
 917                 return -EINVAL;
 918         }
 919         tl_tpg->tl_fabric_prot_type = val;
 920
 921         return count;
 922 }
 923
 924 TF_TPG_ATTRIB_ATTR(tcm_loop, fabric_prot_type, S_IRUGO | S_IWUSR);
 925
 926 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
 927         &tcm_loop_tpg_attrib_fabric_prot_type.attr,
 928         NULL,
 929 };
 930
 931 /* Start items for tcm_loop_nexus_cit */
 932
 933 static int tcm_loop_make_nexus(
 934         struct tcm_loop_tpg *tl_tpg,
 935         const char *name)
 936 {
 937         struct se_portal_group *se_tpg;
 938         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 939         struct tcm_loop_nexus *tl_nexus;
 940         int ret = -ENOMEM;
 941
 942         if (tl_tpg->tl_nexus) {
 943                 pr_debug("tl_tpg->tl_nexus already exists\n");
 944                 return -EEXIST;
 945         }
 946         se_tpg = &tl_tpg->tl_se_tpg;
 947
 948         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 949         if (!tl_nexus) {
 950                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 951                 return -ENOMEM;
 952         }
 953         /*
 954          * Initialize the struct se_session pointer
 955          */
 956         tl_nexus->se_sess = transport_init_session(
 957                                 TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS);
 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         /* Now, register the SAS I_T Nexus as active. */
 974         transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
 975                         tl_nexus->se_sess, tl_nexus);
 976         tl_tpg->tl_nexus = tl_nexus;
 977         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 978                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 979                 name);
 980         return 0;
 981
 982 out:
 983         kfree(tl_nexus);
 984         return ret;
 985 }
 986
 987 static int tcm_loop_drop_nexus(
 988         struct tcm_loop_tpg *tpg)
 989 {
 990         struct se_session *se_sess;
 991         struct tcm_loop_nexus *tl_nexus;
 992
 993         tl_nexus = tpg->tl_nexus;
 994         if (!tl_nexus)
 995                 return -ENODEV;
 996
 997         se_sess = tl_nexus->se_sess;
 998         if (!se_sess)
 999                 return -ENODEV;
1000
1001         if (atomic_read(&tpg->tl_tpg_port_count)) {
1002                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
1003                         " active TPG port count: %d\n",
1004                         atomic_read(&tpg->tl_tpg_port_count));
1005                 return -EPERM;
1006         }
1007
1008         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1009                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
1010                 tl_nexus->se_sess->se_node_acl->initiatorname);
1011         /*
1012          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1013          */
1014         transport_deregister_session(tl_nexus->se_sess);
1015         tpg->tl_nexus = NULL;
1016         kfree(tl_nexus);
1017         return 0;
1018 }
1019
1020 /* End items for tcm_loop_nexus_cit */
1021
1022 static ssize_t tcm_loop_tpg_show_nexus(
1023         struct se_portal_group *se_tpg,
1024         char *page)
1025 {
1026         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1027                         struct tcm_loop_tpg, tl_se_tpg);
1028         struct tcm_loop_nexus *tl_nexus;
1029         ssize_t ret;
1030
1031         tl_nexus = tl_tpg->tl_nexus;
1032         if (!tl_nexus)
1033                 return -ENODEV;
1034
1035         ret = snprintf(page, PAGE_SIZE, "%s\n",
1036                 tl_nexus->se_sess->se_node_acl->initiatorname);
1037
1038         return ret;
1039 }
1040
1041 static ssize_t tcm_loop_tpg_store_nexus(
1042         struct se_portal_group *se_tpg,
1043         const char *page,
1044         size_t count)
1045 {
1046         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1047                         struct tcm_loop_tpg, tl_se_tpg);
1048         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1049         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1050         int ret;
1051         /*
1052          * Shutdown the active I_T nexus if 'NULL' is passed..
1053          */
1054         if (!strncmp(page, "NULL", 4)) {
1055                 ret = tcm_loop_drop_nexus(tl_tpg);
1056                 return (!ret) ? count : ret;
1057         }
1058         /*
1059          * Otherwise make sure the passed virtual Initiator port WWN matches
1060          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1061          * tcm_loop_make_nexus()
1062          */
1063         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1064                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1065                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1066                 return -EINVAL;
1067         }
1068         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1069
1070         ptr = strstr(i_port, "naa.");
1071         if (ptr) {
1072                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1073                         pr_err("Passed SAS Initiator Port %s does not"
1074                                 " match target port protoid: %s\n", i_port,
1075                                 tcm_loop_dump_proto_id(tl_hba));
1076                         return -EINVAL;
1077                 }
1078                 port_ptr = &i_port[0];
1079                 goto check_newline;
1080         }
1081         ptr = strstr(i_port, "fc.");
1082         if (ptr) {
1083                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1084                         pr_err("Passed FCP Initiator Port %s does not"
1085                                 " match target port protoid: %s\n", i_port,
1086                                 tcm_loop_dump_proto_id(tl_hba));
1087                         return -EINVAL;
1088                 }
1089                 port_ptr = &i_port[3]; /* Skip over "fc." */
1090                 goto check_newline;
1091         }
1092         ptr = strstr(i_port, "iqn.");
1093         if (ptr) {
1094                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1095                         pr_err("Passed iSCSI Initiator Port %s does not"
1096                                 " match target port protoid: %s\n", i_port,
1097                                 tcm_loop_dump_proto_id(tl_hba));
1098                         return -EINVAL;
1099                 }
1100                 port_ptr = &i_port[0];
1101                 goto check_newline;
1102         }
1103         pr_err("Unable to locate prefix for emulated Initiator Port:"
1104                         " %s\n", i_port);
1105         return -EINVAL;
1106         /*
1107          * Clear any trailing newline for the NAA WWN
1108          */
1109 check_newline:
1110         if (i_port[strlen(i_port)-1] == '\n')
1111                 i_port[strlen(i_port)-1] = '\0';
1112
1113         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1114         if (ret < 0)
1115                 return ret;
1116
1117         return count;
1118 }
1119
1120 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1121
1122 static ssize_t tcm_loop_tpg_show_transport_status(
1123         struct se_portal_group *se_tpg,
1124         char *page)
1125 {
1126         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1127                         struct tcm_loop_tpg, tl_se_tpg);
1128         const char *status = NULL;
1129         ssize_t ret = -EINVAL;
1130
1131         switch (tl_tpg->tl_transport_status) {
1132         case TCM_TRANSPORT_ONLINE:
1133                 status = "online";
1134                 break;
1135         case TCM_TRANSPORT_OFFLINE:
1136                 status = "offline";
1137                 break;
1138         default:
1139                 break;
1140         }
1141
1142         if (status)
1143                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1144
1145         return ret;
1146 }
1147
1148 static ssize_t tcm_loop_tpg_store_transport_status(
1149         struct se_portal_group *se_tpg,
1150         const char *page,
1151         size_t count)
1152 {
1153         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1154                         struct tcm_loop_tpg, tl_se_tpg);
1155
1156         if (!strncmp(page, "online", 6)) {
1157                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1158                 return count;
1159         }
1160         if (!strncmp(page, "offline", 7)) {
1161                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1162                 return count;
1163         }
1164         return -EINVAL;
1165 }
1166
1167 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1168
1169 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1170         &tcm_loop_tpg_nexus.attr,
1171         &tcm_loop_tpg_transport_status.attr,
1172         NULL,
1173 };
1174
1175 /* Start items for tcm_loop_naa_cit */
1176
1177 static struct se_portal_group *tcm_loop_make_naa_tpg(
1178         struct se_wwn *wwn,
1179         struct config_group *group,
1180         const char *name)
1181 {
1182         struct tcm_loop_hba *tl_hba = container_of(wwn,
1183                         struct tcm_loop_hba, tl_hba_wwn);
1184         struct tcm_loop_tpg *tl_tpg;
1185         int ret;
1186         unsigned long tpgt;
1187
1188         if (strstr(name, "tpgt_") != name) {
1189                 pr_err("Unable to locate \"tpgt_#\" directory"
1190                                 " group\n");
1191                 return ERR_PTR(-EINVAL);
1192         }
1193         if (kstrtoul(name+5, 10, &tpgt))
1194                 return ERR_PTR(-EINVAL);
1195
1196         if (tpgt >= TL_TPGS_PER_HBA) {
1197                 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA:"
1198                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1199                 return ERR_PTR(-EINVAL);
1200         }
1201         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1202         tl_tpg->tl_hba = tl_hba;
1203         tl_tpg->tl_tpgt = tpgt;
1204         /*
1205          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1206          */
1207         ret = core_tpg_register(&loop_ops, wwn, &tl_tpg->tl_se_tpg,
1208                                 tl_hba->tl_proto_id);
1209         if (ret < 0)
1210                 return ERR_PTR(-ENOMEM);
1211
1212         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1213                 " Target Port %s,t,0x%04lx\n", tcm_loop_dump_proto_id(tl_hba),
1214                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1215
1216         return &tl_tpg->tl_se_tpg;
1217 }
1218
1219 static void tcm_loop_drop_naa_tpg(
1220         struct se_portal_group *se_tpg)
1221 {
1222         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1223         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1224                                 struct tcm_loop_tpg, tl_se_tpg);
1225         struct tcm_loop_hba *tl_hba;
1226         unsigned short tpgt;
1227
1228         tl_hba = tl_tpg->tl_hba;
1229         tpgt = tl_tpg->tl_tpgt;
1230         /*
1231          * Release the I_T Nexus for the Virtual SAS link if present
1232          */
1233         tcm_loop_drop_nexus(tl_tpg);
1234         /*
1235          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1236          */
1237         core_tpg_deregister(se_tpg);
1238
1239         tl_tpg->tl_hba = NULL;
1240         tl_tpg->tl_tpgt = 0;
1241
1242         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1243                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1244                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1245 }
1246
1247 /* End items for tcm_loop_naa_cit */
1248
1249 /* Start items for tcm_loop_cit */
1250
1251 static struct se_wwn *tcm_loop_make_scsi_hba(
1252         struct target_fabric_configfs *tf,
1253         struct config_group *group,
1254         const char *name)
1255 {
1256         struct tcm_loop_hba *tl_hba;
1257         struct Scsi_Host *sh;
1258         char *ptr;
1259         int ret, off = 0;
1260
1261         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1262         if (!tl_hba) {
1263                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1264                 return ERR_PTR(-ENOMEM);
1265         }
1266         /*
1267          * Determine the emulated Protocol Identifier and Target Port Name
1268          * based on the incoming configfs directory name.
1269          */
1270         ptr = strstr(name, "naa.");
1271         if (ptr) {
1272                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1273                 goto check_len;
1274         }
1275         ptr = strstr(name, "fc.");
1276         if (ptr) {
1277                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1278                 off = 3; /* Skip over "fc." */
1279                 goto check_len;
1280         }
1281         ptr = strstr(name, "iqn.");
1282         if (!ptr) {
1283                 pr_err("Unable to locate prefix for emulated Target "
1284                                 "Port: %s\n", name);
1285                 ret = -EINVAL;
1286                 goto out;
1287         }
1288         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1289
1290 check_len:
1291         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1292                 pr_err("Emulated NAA %s Address: %s, exceeds"
1293                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1294                         TL_WWN_ADDR_LEN);
1295                 ret = -EINVAL;
1296                 goto out;
1297         }
1298         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1299
1300         /*
1301          * Call device_register(tl_hba->dev) to register the emulated
1302          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1303          * device_register() callbacks in tcm_loop_driver_probe()
1304          */
1305         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1306         if (ret)
1307                 goto out;
1308
1309         sh = tl_hba->sh;
1310         tcm_loop_hba_no_cnt++;
1311         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1312                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1313                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1314
1315         return &tl_hba->tl_hba_wwn;
1316 out:
1317         kfree(tl_hba);
1318         return ERR_PTR(ret);
1319 }
1320
1321 static void tcm_loop_drop_scsi_hba(
1322         struct se_wwn *wwn)
1323 {
1324         struct tcm_loop_hba *tl_hba = container_of(wwn,
1325                                 struct tcm_loop_hba, tl_hba_wwn);
1326
1327         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1328                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1329                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1330         /*
1331          * Call device_unregister() on the original tl_hba->dev.
1332          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1333          * release *tl_hba;
1334          */
1335         device_unregister(&tl_hba->dev);
1336 }
1337
1338 /* Start items for tcm_loop_cit */
1339 static ssize_t tcm_loop_wwn_show_attr_version(
1340         struct target_fabric_configfs *tf,
1341         char *page)
1342 {
1343         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1344 }
1345
1346 TF_WWN_ATTR_RO(tcm_loop, version);
1347
1348 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1349         &tcm_loop_wwn_version.attr,
1350         NULL,
1351 };
1352
1353 /* End items for tcm_loop_cit */
1354
1355 static const struct target_core_fabric_ops loop_ops = {
1356         .module                         = THIS_MODULE,
1357         .name                           = "loopback",
1358         .get_fabric_name                = tcm_loop_get_fabric_name,
1359         .get_fabric_proto_ident         = tcm_loop_get_fabric_proto_ident,
1360         .tpg_get_wwn                    = tcm_loop_get_endpoint_wwn,
1361         .tpg_get_tag                    = tcm_loop_get_tag,
1362         .tpg_get_pr_transport_id        = tcm_loop_get_pr_transport_id,
1363         .tpg_get_pr_transport_id_len    = tcm_loop_get_pr_transport_id_len,
1364         .tpg_parse_pr_out_transport_id  = tcm_loop_parse_pr_out_transport_id,
1365         .tpg_check_demo_mode            = tcm_loop_check_demo_mode,
1366         .tpg_check_demo_mode_cache      = tcm_loop_check_demo_mode_cache,
1367         .tpg_check_demo_mode_write_protect =
1368                                 tcm_loop_check_demo_mode_write_protect,
1369         .tpg_check_prod_mode_write_protect =
1370                                 tcm_loop_check_prod_mode_write_protect,
1371         .tpg_check_prot_fabric_only     = tcm_loop_check_prot_fabric_only,
1372         .tpg_get_inst_index             = tcm_loop_get_inst_index,
1373         .check_stop_free                = tcm_loop_check_stop_free,
1374         .release_cmd                    = tcm_loop_release_cmd,
1375         .shutdown_session               = tcm_loop_shutdown_session,
1376         .close_session                  = tcm_loop_close_session,
1377         .sess_get_index                 = tcm_loop_sess_get_index,
1378         .write_pending                  = tcm_loop_write_pending,
1379         .write_pending_status           = tcm_loop_write_pending_status,
1380         .set_default_node_attributes    = tcm_loop_set_default_node_attributes,
1381         .get_task_tag                   = tcm_loop_get_task_tag,
1382         .get_cmd_state                  = tcm_loop_get_cmd_state,
1383         .queue_data_in                  = tcm_loop_queue_data_in,
1384         .queue_status                   = tcm_loop_queue_status,
1385         .queue_tm_rsp                   = tcm_loop_queue_tm_rsp,
1386         .aborted_task                   = tcm_loop_aborted_task,
1387         .fabric_make_wwn                = tcm_loop_make_scsi_hba,
1388         .fabric_drop_wwn                = tcm_loop_drop_scsi_hba,
1389         .fabric_make_tpg                = tcm_loop_make_naa_tpg,
1390         .fabric_drop_tpg                = tcm_loop_drop_naa_tpg,
1391         .fabric_post_link               = tcm_loop_port_link,
1392         .fabric_pre_unlink              = tcm_loop_port_unlink,
1393         .tfc_wwn_attrs                  = tcm_loop_wwn_attrs,
1394         .tfc_tpg_base_attrs             = tcm_loop_tpg_attrs,
1395         .tfc_tpg_attrib_attrs           = tcm_loop_tpg_attrib_attrs,
1396 };
1397
1398 static int __init tcm_loop_fabric_init(void)
1399 {
1400         int ret = -ENOMEM;
1401
1402         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1403         if (!tcm_loop_workqueue)
1404                 goto out;
1405
1406         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1407                                 sizeof(struct tcm_loop_cmd),
1408                                 __alignof__(struct tcm_loop_cmd),
1409                                 0, NULL);
1410         if (!tcm_loop_cmd_cache) {
1411                 pr_debug("kmem_cache_create() for"
1412                         " tcm_loop_cmd_cache failed\n");
1413                 goto out_destroy_workqueue;
1414         }
1415
1416         ret = tcm_loop_alloc_core_bus();
1417         if (ret)
1418                 goto out_destroy_cache;
1419
1420         ret = target_register_template(&loop_ops);
1421         if (ret)
1422                 goto out_release_core_bus;
1423
1424         return 0;
1425
1426 out_release_core_bus:
1427         tcm_loop_release_core_bus();
1428 out_destroy_cache:
1429         kmem_cache_destroy(tcm_loop_cmd_cache);
1430 out_destroy_workqueue:
1431         destroy_workqueue(tcm_loop_workqueue);
1432 out:
1433         return ret;
1434 }
1435
1436 static void __exit tcm_loop_fabric_exit(void)
1437 {
1438         target_unregister_template(&loop_ops);
1439         tcm_loop_release_core_bus();
1440         kmem_cache_destroy(tcm_loop_cmd_cache);
1441         destroy_workqueue(tcm_loop_workqueue);
1442 }
1443
1444 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1445 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1446 MODULE_LICENSE("GPL");
1447 module_init(tcm_loop_fabric_init);
1448 module_exit(tcm_loop_fabric_exit);