kernel/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 = TL_SCSI_MAX_CMD_LEN;
 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 u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 524 {
 525         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 526         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 527         /*
 528          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 529          * time based on the protocol dependent prefix of the passed configfs group.
 530          *
 531          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 532          * ProtocolID using target_core_fabric_lib.c symbols.
 533          */
 534         switch (tl_hba->tl_proto_id) {
 535         case SCSI_PROTOCOL_SAS:
 536                 return sas_get_fabric_proto_ident(se_tpg);
 537         case SCSI_PROTOCOL_FCP:
 538                 return fc_get_fabric_proto_ident(se_tpg);
 539         case SCSI_PROTOCOL_ISCSI:
 540                 return iscsi_get_fabric_proto_ident(se_tpg);
 541         default:
 542                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 543                         " SAS emulation\n", tl_hba->tl_proto_id);
 544                 break;
 545         }
 546
 547         return sas_get_fabric_proto_ident(se_tpg);
 548 }
 549
 550 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 551 {
 552         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 553         /*
 554          * Return the passed NAA identifier for the SAS Target Port
 555          */
 556         return &tl_tpg->tl_hba->tl_wwn_address[0];
 557 }
 558
 559 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 560 {
 561         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 562         /*
 563          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 564          * to represent the SCSI Target Port.
 565          */
 566         return tl_tpg->tl_tpgt;
 567 }
 568
 569 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 570 {
 571         return 1;
 572 }
 573
 574 static u32 tcm_loop_get_pr_transport_id(
 575         struct se_portal_group *se_tpg,
 576         struct se_node_acl *se_nacl,
 577         struct t10_pr_registration *pr_reg,
 578         int *format_code,
 579         unsigned char *buf)
 580 {
 581         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 582         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 583
 584         switch (tl_hba->tl_proto_id) {
 585         case SCSI_PROTOCOL_SAS:
 586                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 587                                         format_code, buf);
 588         case SCSI_PROTOCOL_FCP:
 589                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 590                                         format_code, buf);
 591         case SCSI_PROTOCOL_ISCSI:
 592                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 593                                         format_code, buf);
 594         default:
 595                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 596                         " SAS emulation\n", tl_hba->tl_proto_id);
 597                 break;
 598         }
 599
 600         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 601                         format_code, buf);
 602 }
 603
 604 static u32 tcm_loop_get_pr_transport_id_len(
 605         struct se_portal_group *se_tpg,
 606         struct se_node_acl *se_nacl,
 607         struct t10_pr_registration *pr_reg,
 608         int *format_code)
 609 {
 610         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 611         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 612
 613         switch (tl_hba->tl_proto_id) {
 614         case SCSI_PROTOCOL_SAS:
 615                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 616                                         format_code);
 617         case SCSI_PROTOCOL_FCP:
 618                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 619                                         format_code);
 620         case SCSI_PROTOCOL_ISCSI:
 621                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 622                                         format_code);
 623         default:
 624                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 625                         " SAS emulation\n", tl_hba->tl_proto_id);
 626                 break;
 627         }
 628
 629         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 630                         format_code);
 631 }
 632
 633 /*
 634  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 635  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 636  */
 637 static char *tcm_loop_parse_pr_out_transport_id(
 638         struct se_portal_group *se_tpg,
 639         const char *buf,
 640         u32 *out_tid_len,
 641         char **port_nexus_ptr)
 642 {
 643         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 644         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 645
 646         switch (tl_hba->tl_proto_id) {
 647         case SCSI_PROTOCOL_SAS:
 648                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 649                                         port_nexus_ptr);
 650         case SCSI_PROTOCOL_FCP:
 651                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 652                                         port_nexus_ptr);
 653         case SCSI_PROTOCOL_ISCSI:
 654                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 655                                         port_nexus_ptr);
 656         default:
 657                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 658                         " SAS emulation\n", tl_hba->tl_proto_id);
 659                 break;
 660         }
 661
 662         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 663                         port_nexus_ptr);
 664 }
 665
 666 /*
 667  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 668  * based upon the incoming fabric dependent SCSI Initiator Port
 669  */
 670 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 671 {
 672         return 1;
 673 }
 674
 675 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 676 {
 677         return 0;
 678 }
 679
 680 /*
 681  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 682  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 683  */
 684 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 685 {
 686         return 0;
 687 }
 688
 689 /*
 690  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 691  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 692  * It has been added here as a nop for target_fabric_tf_ops_check()
 693  */
 694 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 695 {
 696         return 0;
 697 }
 698
 699 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
 700 {
 701         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 702                                                    tl_se_tpg);
 703         return tl_tpg->tl_fabric_prot_type;
 704 }
 705
 706 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 707         struct se_portal_group *se_tpg)
 708 {
 709         struct tcm_loop_nacl *tl_nacl;
 710
 711         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 712         if (!tl_nacl) {
 713                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 714                 return NULL;
 715         }
 716
 717         return &tl_nacl->se_node_acl;
 718 }
 719
 720 static void tcm_loop_tpg_release_fabric_acl(
 721         struct se_portal_group *se_tpg,
 722         struct se_node_acl *se_nacl)
 723 {
 724         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 725                                 struct tcm_loop_nacl, se_node_acl);
 726
 727         kfree(tl_nacl);
 728 }
 729
 730 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 731 {
 732         return 1;
 733 }
 734
 735 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 736 {
 737         return 1;
 738 }
 739
 740 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 741 {
 742         return;
 743 }
 744
 745 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 746 {
 747         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 748                         struct tcm_loop_cmd, tl_se_cmd);
 749
 750         return tl_cmd->sc_cmd_tag;
 751 }
 752
 753 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 754 {
 755         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 756                         struct tcm_loop_cmd, tl_se_cmd);
 757
 758         return tl_cmd->sc_cmd_state;
 759 }
 760
 761 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 762 {
 763         return 0;
 764 }
 765
 766 static void tcm_loop_close_session(struct se_session *se_sess)
 767 {
 768         return;
 769 };
 770
 771 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 772 {
 773         /*
 774          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 775          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 776          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 777          * format with transport_generic_map_mem_to_cmd().
 778          *
 779          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 780          * object execution queue.
 781          */
 782         target_execute_cmd(se_cmd);
 783         return 0;
 784 }
 785
 786 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 787 {
 788         return 0;
 789 }
 790
 791 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 792 {
 793         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 794                                 struct tcm_loop_cmd, tl_se_cmd);
 795         struct scsi_cmnd *sc = tl_cmd->sc;
 796
 797         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 798                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 799
 800         sc->result = SAM_STAT_GOOD;
 801         set_host_byte(sc, DID_OK);
 802         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 803             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 804                 scsi_set_resid(sc, se_cmd->residual_count);
 805         sc->scsi_done(sc);
 806         return 0;
 807 }
 808
 809 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 810 {
 811         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 812                                 struct tcm_loop_cmd, tl_se_cmd);
 813         struct scsi_cmnd *sc = tl_cmd->sc;
 814
 815         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 816                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 817
 818         if (se_cmd->sense_buffer &&
 819            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 820             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 821
 822                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 823                                 SCSI_SENSE_BUFFERSIZE);
 824                 sc->result = SAM_STAT_CHECK_CONDITION;
 825                 set_driver_byte(sc, DRIVER_SENSE);
 826         } else
 827                 sc->result = se_cmd->scsi_status;
 828
 829         set_host_byte(sc, DID_OK);
 830         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 831             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 832                 scsi_set_resid(sc, se_cmd->residual_count);
 833         sc->scsi_done(sc);
 834         return 0;
 835 }
 836
 837 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 838 {
 839         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 840         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 841         /*
 842          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 843          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 844          */
 845         atomic_set(&tl_tmr->tmr_complete, 1);
 846         wake_up(&tl_tmr->tl_tmr_wait);
 847 }
 848
 849 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 850 {
 851         return;
 852 }
 853
 854 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 855 {
 856         switch (tl_hba->tl_proto_id) {
 857         case SCSI_PROTOCOL_SAS:
 858                 return "SAS";
 859         case SCSI_PROTOCOL_FCP:
 860                 return "FCP";
 861         case SCSI_PROTOCOL_ISCSI:
 862                 return "iSCSI";
 863         default:
 864                 break;
 865         }
 866
 867         return "Unknown";
 868 }
 869
 870 /* Start items for tcm_loop_port_cit */
 871
 872 static int tcm_loop_port_link(
 873         struct se_portal_group *se_tpg,
 874         struct se_lun *lun)
 875 {
 876         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 877                                 struct tcm_loop_tpg, tl_se_tpg);
 878         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 879
 880         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 881         /*
 882          * Add Linux/SCSI struct scsi_device by HCTL
 883          */
 884         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 885
 886         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 887         return 0;
 888 }
 889
 890 static void tcm_loop_port_unlink(
 891         struct se_portal_group *se_tpg,
 892         struct se_lun *se_lun)
 893 {
 894         struct scsi_device *sd;
 895         struct tcm_loop_hba *tl_hba;
 896         struct tcm_loop_tpg *tl_tpg;
 897
 898         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 899         tl_hba = tl_tpg->tl_hba;
 900
 901         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 902                                 se_lun->unpacked_lun);
 903         if (!sd) {
 904                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 905                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 906                 return;
 907         }
 908         /*
 909          * Remove Linux/SCSI struct scsi_device by HCTL
 910          */
 911         scsi_remove_device(sd);
 912         scsi_device_put(sd);
 913
 914         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 915
 916         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 917 }
 918
 919 /* End items for tcm_loop_port_cit */
 920
 921 static ssize_t tcm_loop_tpg_attrib_show_fabric_prot_type(
 922         struct se_portal_group *se_tpg,
 923         char *page)
 924 {
 925         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 926                                                    tl_se_tpg);
 927
 928         return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
 929 }
 930
 931 static ssize_t tcm_loop_tpg_attrib_store_fabric_prot_type(
 932         struct se_portal_group *se_tpg,
 933         const char *page,
 934         size_t count)
 935 {
 936         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 937                                                    tl_se_tpg);
 938         unsigned long val;
 939         int ret = kstrtoul(page, 0, &val);
 940
 941         if (ret) {
 942                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
 943                 return ret;
 944         }
 945         if (val != 0 && val != 1 && val != 3) {
 946                 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
 947                 return -EINVAL;
 948         }
 949         tl_tpg->tl_fabric_prot_type = val;
 950
 951         return count;
 952 }
 953
 954 TF_TPG_ATTRIB_ATTR(tcm_loop, fabric_prot_type, S_IRUGO | S_IWUSR);
 955
 956 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
 957         &tcm_loop_tpg_attrib_fabric_prot_type.attr,
 958         NULL,
 959 };
 960
 961 /* Start items for tcm_loop_nexus_cit */
 962
 963 static int tcm_loop_make_nexus(
 964         struct tcm_loop_tpg *tl_tpg,
 965         const char *name)
 966 {
 967         struct se_portal_group *se_tpg;
 968         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 969         struct tcm_loop_nexus *tl_nexus;
 970         int ret = -ENOMEM;
 971
 972         if (tl_tpg->tl_nexus) {
 973                 pr_debug("tl_tpg->tl_nexus already exists\n");
 974                 return -EEXIST;
 975         }
 976         se_tpg = &tl_tpg->tl_se_tpg;
 977
 978         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 979         if (!tl_nexus) {
 980                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
 981                 return -ENOMEM;
 982         }
 983         /*
 984          * Initialize the struct se_session pointer
 985          */
 986         tl_nexus->se_sess = transport_init_session(
 987                                 TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS);
 988         if (IS_ERR(tl_nexus->se_sess)) {
 989                 ret = PTR_ERR(tl_nexus->se_sess);
 990                 goto out;
 991         }
 992         /*
 993          * Since we are running in 'demo mode' this call with generate a
 994          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
 995          * Initiator port name of the passed configfs group 'name'.
 996          */
 997         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 998                                 se_tpg, (unsigned char *)name);
 999         if (!tl_nexus->se_sess->se_node_acl) {
1000                 transport_free_session(tl_nexus->se_sess);
1001                 goto out;
1002         }
1003         /* Now, register the SAS I_T Nexus as active. */
1004         transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1005                         tl_nexus->se_sess, tl_nexus);
1006         tl_tpg->tl_nexus = tl_nexus;
1007         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1008                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1009                 name);
1010         return 0;
1011
1012 out:
1013         kfree(tl_nexus);
1014         return ret;
1015 }
1016
1017 static int tcm_loop_drop_nexus(
1018         struct tcm_loop_tpg *tpg)
1019 {
1020         struct se_session *se_sess;
1021         struct tcm_loop_nexus *tl_nexus;
1022
1023         tl_nexus = tpg->tl_nexus;
1024         if (!tl_nexus)
1025                 return -ENODEV;
1026
1027         se_sess = tl_nexus->se_sess;
1028         if (!se_sess)
1029                 return -ENODEV;
1030
1031         if (atomic_read(&tpg->tl_tpg_port_count)) {
1032                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
1033                         " active TPG port count: %d\n",
1034                         atomic_read(&tpg->tl_tpg_port_count));
1035                 return -EPERM;
1036         }
1037
1038         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1039                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
1040                 tl_nexus->se_sess->se_node_acl->initiatorname);
1041         /*
1042          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1043          */
1044         transport_deregister_session(tl_nexus->se_sess);
1045         tpg->tl_nexus = NULL;
1046         kfree(tl_nexus);
1047         return 0;
1048 }
1049
1050 /* End items for tcm_loop_nexus_cit */
1051
1052 static ssize_t tcm_loop_tpg_show_nexus(
1053         struct se_portal_group *se_tpg,
1054         char *page)
1055 {
1056         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1057                         struct tcm_loop_tpg, tl_se_tpg);
1058         struct tcm_loop_nexus *tl_nexus;
1059         ssize_t ret;
1060
1061         tl_nexus = tl_tpg->tl_nexus;
1062         if (!tl_nexus)
1063                 return -ENODEV;
1064
1065         ret = snprintf(page, PAGE_SIZE, "%s\n",
1066                 tl_nexus->se_sess->se_node_acl->initiatorname);
1067
1068         return ret;
1069 }
1070
1071 static ssize_t tcm_loop_tpg_store_nexus(
1072         struct se_portal_group *se_tpg,
1073         const char *page,
1074         size_t count)
1075 {
1076         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1077                         struct tcm_loop_tpg, tl_se_tpg);
1078         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1079         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1080         int ret;
1081         /*
1082          * Shutdown the active I_T nexus if 'NULL' is passed..
1083          */
1084         if (!strncmp(page, "NULL", 4)) {
1085                 ret = tcm_loop_drop_nexus(tl_tpg);
1086                 return (!ret) ? count : ret;
1087         }
1088         /*
1089          * Otherwise make sure the passed virtual Initiator port WWN matches
1090          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1091          * tcm_loop_make_nexus()
1092          */
1093         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1094                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1095                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1096                 return -EINVAL;
1097         }
1098         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1099
1100         ptr = strstr(i_port, "naa.");
1101         if (ptr) {
1102                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1103                         pr_err("Passed SAS Initiator Port %s does not"
1104                                 " match target port protoid: %s\n", i_port,
1105                                 tcm_loop_dump_proto_id(tl_hba));
1106                         return -EINVAL;
1107                 }
1108                 port_ptr = &i_port[0];
1109                 goto check_newline;
1110         }
1111         ptr = strstr(i_port, "fc.");
1112         if (ptr) {
1113                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1114                         pr_err("Passed FCP Initiator Port %s does not"
1115                                 " match target port protoid: %s\n", i_port,
1116                                 tcm_loop_dump_proto_id(tl_hba));
1117                         return -EINVAL;
1118                 }
1119                 port_ptr = &i_port[3]; /* Skip over "fc." */
1120                 goto check_newline;
1121         }
1122         ptr = strstr(i_port, "iqn.");
1123         if (ptr) {
1124                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1125                         pr_err("Passed iSCSI Initiator Port %s does not"
1126                                 " match target port protoid: %s\n", i_port,
1127                                 tcm_loop_dump_proto_id(tl_hba));
1128                         return -EINVAL;
1129                 }
1130                 port_ptr = &i_port[0];
1131                 goto check_newline;
1132         }
1133         pr_err("Unable to locate prefix for emulated Initiator Port:"
1134                         " %s\n", i_port);
1135         return -EINVAL;
1136         /*
1137          * Clear any trailing newline for the NAA WWN
1138          */
1139 check_newline:
1140         if (i_port[strlen(i_port)-1] == '\n')
1141                 i_port[strlen(i_port)-1] = '\0';
1142
1143         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1144         if (ret < 0)
1145                 return ret;
1146
1147         return count;
1148 }
1149
1150 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1151
1152 static ssize_t tcm_loop_tpg_show_transport_status(
1153         struct se_portal_group *se_tpg,
1154         char *page)
1155 {
1156         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1157                         struct tcm_loop_tpg, tl_se_tpg);
1158         const char *status = NULL;
1159         ssize_t ret = -EINVAL;
1160
1161         switch (tl_tpg->tl_transport_status) {
1162         case TCM_TRANSPORT_ONLINE:
1163                 status = "online";
1164                 break;
1165         case TCM_TRANSPORT_OFFLINE:
1166                 status = "offline";
1167                 break;
1168         default:
1169                 break;
1170         }
1171
1172         if (status)
1173                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1174
1175         return ret;
1176 }
1177
1178 static ssize_t tcm_loop_tpg_store_transport_status(
1179         struct se_portal_group *se_tpg,
1180         const char *page,
1181         size_t count)
1182 {
1183         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1184                         struct tcm_loop_tpg, tl_se_tpg);
1185
1186         if (!strncmp(page, "online", 6)) {
1187                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1188                 return count;
1189         }
1190         if (!strncmp(page, "offline", 7)) {
1191                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1192                 return count;
1193         }
1194         return -EINVAL;
1195 }
1196
1197 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1198
1199 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1200         &tcm_loop_tpg_nexus.attr,
1201         &tcm_loop_tpg_transport_status.attr,
1202         NULL,
1203 };
1204
1205 /* Start items for tcm_loop_naa_cit */
1206
1207 static struct se_portal_group *tcm_loop_make_naa_tpg(
1208         struct se_wwn *wwn,
1209         struct config_group *group,
1210         const char *name)
1211 {
1212         struct tcm_loop_hba *tl_hba = container_of(wwn,
1213                         struct tcm_loop_hba, tl_hba_wwn);
1214         struct tcm_loop_tpg *tl_tpg;
1215         int ret;
1216         unsigned long tpgt;
1217
1218         if (strstr(name, "tpgt_") != name) {
1219                 pr_err("Unable to locate \"tpgt_#\" directory"
1220                                 " group\n");
1221                 return ERR_PTR(-EINVAL);
1222         }
1223         if (kstrtoul(name+5, 10, &tpgt))
1224                 return ERR_PTR(-EINVAL);
1225
1226         if (tpgt >= TL_TPGS_PER_HBA) {
1227                 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA:"
1228                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1229                 return ERR_PTR(-EINVAL);
1230         }
1231         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1232         tl_tpg->tl_hba = tl_hba;
1233         tl_tpg->tl_tpgt = tpgt;
1234         /*
1235          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1236          */
1237         ret = core_tpg_register(&loop_ops, wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1238                         TRANSPORT_TPG_TYPE_NORMAL);
1239         if (ret < 0)
1240                 return ERR_PTR(-ENOMEM);
1241
1242         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1243                 " Target Port %s,t,0x%04lx\n", tcm_loop_dump_proto_id(tl_hba),
1244                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1245
1246         return &tl_tpg->tl_se_tpg;
1247 }
1248
1249 static void tcm_loop_drop_naa_tpg(
1250         struct se_portal_group *se_tpg)
1251 {
1252         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1253         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1254                                 struct tcm_loop_tpg, tl_se_tpg);
1255         struct tcm_loop_hba *tl_hba;
1256         unsigned short tpgt;
1257
1258         tl_hba = tl_tpg->tl_hba;
1259         tpgt = tl_tpg->tl_tpgt;
1260         /*
1261          * Release the I_T Nexus for the Virtual SAS link if present
1262          */
1263         tcm_loop_drop_nexus(tl_tpg);
1264         /*
1265          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1266          */
1267         core_tpg_deregister(se_tpg);
1268
1269         tl_tpg->tl_hba = NULL;
1270         tl_tpg->tl_tpgt = 0;
1271
1272         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1273                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1274                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1275 }
1276
1277 /* End items for tcm_loop_naa_cit */
1278
1279 /* Start items for tcm_loop_cit */
1280
1281 static struct se_wwn *tcm_loop_make_scsi_hba(
1282         struct target_fabric_configfs *tf,
1283         struct config_group *group,
1284         const char *name)
1285 {
1286         struct tcm_loop_hba *tl_hba;
1287         struct Scsi_Host *sh;
1288         char *ptr;
1289         int ret, off = 0;
1290
1291         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1292         if (!tl_hba) {
1293                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1294                 return ERR_PTR(-ENOMEM);
1295         }
1296         /*
1297          * Determine the emulated Protocol Identifier and Target Port Name
1298          * based on the incoming configfs directory name.
1299          */
1300         ptr = strstr(name, "naa.");
1301         if (ptr) {
1302                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1303                 goto check_len;
1304         }
1305         ptr = strstr(name, "fc.");
1306         if (ptr) {
1307                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1308                 off = 3; /* Skip over "fc." */
1309                 goto check_len;
1310         }
1311         ptr = strstr(name, "iqn.");
1312         if (!ptr) {
1313                 pr_err("Unable to locate prefix for emulated Target "
1314                                 "Port: %s\n", name);
1315                 ret = -EINVAL;
1316                 goto out;
1317         }
1318         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1319
1320 check_len:
1321         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1322                 pr_err("Emulated NAA %s Address: %s, exceeds"
1323                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1324                         TL_WWN_ADDR_LEN);
1325                 ret = -EINVAL;
1326                 goto out;
1327         }
1328         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1329
1330         /*
1331          * Call device_register(tl_hba->dev) to register the emulated
1332          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1333          * device_register() callbacks in tcm_loop_driver_probe()
1334          */
1335         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1336         if (ret)
1337                 goto out;
1338
1339         sh = tl_hba->sh;
1340         tcm_loop_hba_no_cnt++;
1341         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1342                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1343                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1344
1345         return &tl_hba->tl_hba_wwn;
1346 out:
1347         kfree(tl_hba);
1348         return ERR_PTR(ret);
1349 }
1350
1351 static void tcm_loop_drop_scsi_hba(
1352         struct se_wwn *wwn)
1353 {
1354         struct tcm_loop_hba *tl_hba = container_of(wwn,
1355                                 struct tcm_loop_hba, tl_hba_wwn);
1356
1357         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1358                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1359                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1360         /*
1361          * Call device_unregister() on the original tl_hba->dev.
1362          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1363          * release *tl_hba;
1364          */
1365         device_unregister(&tl_hba->dev);
1366 }
1367
1368 /* Start items for tcm_loop_cit */
1369 static ssize_t tcm_loop_wwn_show_attr_version(
1370         struct target_fabric_configfs *tf,
1371         char *page)
1372 {
1373         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1374 }
1375
1376 TF_WWN_ATTR_RO(tcm_loop, version);
1377
1378 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1379         &tcm_loop_wwn_version.attr,
1380         NULL,
1381 };
1382
1383 /* End items for tcm_loop_cit */
1384
1385 static const struct target_core_fabric_ops loop_ops = {
1386         .module                         = THIS_MODULE,
1387         .name                           = "loopback",
1388         .get_fabric_name                = tcm_loop_get_fabric_name,
1389         .get_fabric_proto_ident         = tcm_loop_get_fabric_proto_ident,
1390         .tpg_get_wwn                    = tcm_loop_get_endpoint_wwn,
1391         .tpg_get_tag                    = tcm_loop_get_tag,
1392         .tpg_get_default_depth          = tcm_loop_get_default_depth,
1393         .tpg_get_pr_transport_id        = tcm_loop_get_pr_transport_id,
1394         .tpg_get_pr_transport_id_len    = tcm_loop_get_pr_transport_id_len,
1395         .tpg_parse_pr_out_transport_id  = tcm_loop_parse_pr_out_transport_id,
1396         .tpg_check_demo_mode            = tcm_loop_check_demo_mode,
1397         .tpg_check_demo_mode_cache      = tcm_loop_check_demo_mode_cache,
1398         .tpg_check_demo_mode_write_protect =
1399                                 tcm_loop_check_demo_mode_write_protect,
1400         .tpg_check_prod_mode_write_protect =
1401                                 tcm_loop_check_prod_mode_write_protect,
1402         .tpg_check_prot_fabric_only     = tcm_loop_check_prot_fabric_only,
1403         .tpg_alloc_fabric_acl           = tcm_loop_tpg_alloc_fabric_acl,
1404         .tpg_release_fabric_acl         = tcm_loop_tpg_release_fabric_acl,
1405         .tpg_get_inst_index             = tcm_loop_get_inst_index,
1406         .check_stop_free                = tcm_loop_check_stop_free,
1407         .release_cmd                    = tcm_loop_release_cmd,
1408         .shutdown_session               = tcm_loop_shutdown_session,
1409         .close_session                  = tcm_loop_close_session,
1410         .sess_get_index                 = tcm_loop_sess_get_index,
1411         .write_pending                  = tcm_loop_write_pending,
1412         .write_pending_status           = tcm_loop_write_pending_status,
1413         .set_default_node_attributes    = tcm_loop_set_default_node_attributes,
1414         .get_task_tag                   = tcm_loop_get_task_tag,
1415         .get_cmd_state                  = tcm_loop_get_cmd_state,
1416         .queue_data_in                  = tcm_loop_queue_data_in,
1417         .queue_status                   = tcm_loop_queue_status,
1418         .queue_tm_rsp                   = tcm_loop_queue_tm_rsp,
1419         .aborted_task                   = tcm_loop_aborted_task,
1420         .fabric_make_wwn                = tcm_loop_make_scsi_hba,
1421         .fabric_drop_wwn                = tcm_loop_drop_scsi_hba,
1422         .fabric_make_tpg                = tcm_loop_make_naa_tpg,
1423         .fabric_drop_tpg                = tcm_loop_drop_naa_tpg,
1424         .fabric_post_link               = tcm_loop_port_link,
1425         .fabric_pre_unlink              = tcm_loop_port_unlink,
1426         .tfc_wwn_attrs                  = tcm_loop_wwn_attrs,
1427         .tfc_tpg_base_attrs             = tcm_loop_tpg_attrs,
1428         .tfc_tpg_attrib_attrs           = tcm_loop_tpg_attrib_attrs,
1429 };
1430
1431 static int __init tcm_loop_fabric_init(void)
1432 {
1433         int ret = -ENOMEM;
1434
1435         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1436         if (!tcm_loop_workqueue)
1437                 goto out;
1438
1439         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1440                                 sizeof(struct tcm_loop_cmd),
1441                                 __alignof__(struct tcm_loop_cmd),
1442                                 0, NULL);
1443         if (!tcm_loop_cmd_cache) {
1444                 pr_debug("kmem_cache_create() for"
1445                         " tcm_loop_cmd_cache failed\n");
1446                 goto out_destroy_workqueue;
1447         }
1448
1449         ret = tcm_loop_alloc_core_bus();
1450         if (ret)
1451                 goto out_destroy_cache;
1452
1453         ret = target_register_template(&loop_ops);
1454         if (ret)
1455                 goto out_release_core_bus;
1456
1457         return 0;
1458
1459 out_release_core_bus:
1460         tcm_loop_release_core_bus();
1461 out_destroy_cache:
1462         kmem_cache_destroy(tcm_loop_cmd_cache);
1463 out_destroy_workqueue:
1464         destroy_workqueue(tcm_loop_workqueue);
1465 out:
1466         return ret;
1467 }
1468
1469 static void __exit tcm_loop_fabric_exit(void)
1470 {
1471         target_unregister_template(&loop_ops);
1472         tcm_loop_release_core_bus();
1473         kmem_cache_destroy(tcm_loop_cmd_cache);
1474         destroy_workqueue(tcm_loop_workqueue);
1475 }
1476
1477 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1478 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1479 MODULE_LICENSE("GPL");
1480 module_init(tcm_loop_fabric_init);
1481 module_exit(tcm_loop_fabric_exit);