drivers/target/loopback/tcm_loop.c

   1 /*******************************************************************************
   2  *
   3  * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4  * for emulated SAS initiator ports
   5  *
   6  * © Copyright 2011 RisingTide Systems LLC.
   7  *
   8  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9  *
  10  * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  ****************************************************************************/
  22
  23 #include <linux/module.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/init.h>
  26 #include <linux/slab.h>
  27 #include <linux/types.h>
  28 #include <linux/configfs.h>
  29 #include <scsi/scsi.h>
  30 #include <scsi/scsi_tcq.h>
  31 #include <scsi/scsi_host.h>
  32 #include <scsi/scsi_device.h>
  33 #include <scsi/scsi_cmnd.h>
  34
  35 #include <target/target_core_base.h>
  36 #include <target/target_core_transport.h>
  37 #include <target/target_core_fabric_ops.h>
  38 #include <target/target_core_fabric_configfs.h>
  39 #include <target/target_core_fabric_lib.h>
  40 #include <target/target_core_configfs.h>
  41 #include <target/target_core_device.h>
  42 #include <target/target_core_tpg.h>
  43 #include <target/target_core_tmr.h>
  44
  45 #include "tcm_loop.h"
  46
  47 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
  48
  49 /* Local pointer to allocated TCM configfs fabric module */
  50 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  51
  52 static struct kmem_cache *tcm_loop_cmd_cache;
  53
  54 static int tcm_loop_hba_no_cnt;
  55
  56 /*
  57  * Allocate a tcm_loop cmd descriptor from target_core_mod code
  58  *
  59  * Can be called from interrupt context in tcm_loop_queuecommand() below
  60  */
  61 static struct se_cmd *tcm_loop_allocate_core_cmd(
  62         struct tcm_loop_hba *tl_hba,
  63         struct se_portal_group *se_tpg,
  64         struct scsi_cmnd *sc)
  65 {
  66         struct se_cmd *se_cmd;
  67         struct se_session *se_sess;
  68         struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus;
  69         struct tcm_loop_cmd *tl_cmd;
  70         int sam_task_attr;
  71
  72         if (!tl_nexus) {
  73                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
  74                                 " does not exist\n");
  75                 set_host_byte(sc, DID_ERROR);
  76                 return NULL;
  77         }
  78         se_sess = tl_nexus->se_sess;
  79
  80         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
  81         if (!tl_cmd) {
  82                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
  83                 set_host_byte(sc, DID_ERROR);
  84                 return NULL;
  85         }
  86         se_cmd = &tl_cmd->tl_se_cmd;
  87         /*
  88          * Save the pointer to struct scsi_cmnd *sc
  89          */
  90         tl_cmd->sc = sc;
  91         /*
  92          * Locate the SAM Task Attr from struct scsi_cmnd *
  93          */
  94         if (sc->device->tagged_supported) {
  95                 switch (sc->tag) {
  96                 case HEAD_OF_QUEUE_TAG:
  97                         sam_task_attr = MSG_HEAD_TAG;
  98                         break;
  99                 case ORDERED_QUEUE_TAG:
 100                         sam_task_attr = MSG_ORDERED_TAG;
 101                         break;
 102                 default:
 103                         sam_task_attr = MSG_SIMPLE_TAG;
 104                         break;
 105                 }
 106         } else
 107                 sam_task_attr = MSG_SIMPLE_TAG;
 108
 109         /*
 110          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 111          */
 112         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
 113                         scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr,
 114                         &tl_cmd->tl_sense_buf[0]);
 115
 116         /*
 117          * Signal BIDI usage with T_TASK(cmd)->t_tasks_bidi
 118          */
 119         if (scsi_bidi_cmnd(sc))
 120                 se_cmd->t_tasks_bidi = 1;
 121         /*
 122          * Locate the struct se_lun pointer and attach it to struct se_cmd
 123          */
 124         if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
 125                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 126                 set_host_byte(sc, DID_NO_CONNECT);
 127                 return NULL;
 128         }
 129
 130         return se_cmd;
 131 }
 132
 133 /*
 134  * Called by struct target_core_fabric_ops->new_cmd_map()
 135  *
 136  * Always called in process context.  A non zero return value
 137  * here will signal to handle an exception based on the return code.
 138  */
 139 static int tcm_loop_new_cmd_map(struct se_cmd *se_cmd)
 140 {
 141         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 142                                 struct tcm_loop_cmd, tl_se_cmd);
 143         struct scsi_cmnd *sc = tl_cmd->sc;
 144         struct scatterlist *sgl_bidi = NULL;
 145         u32 sgl_bidi_count = 0;
 146         int ret;
 147         /*
 148          * Allocate the necessary tasks to complete the received CDB+data
 149          */
 150         ret = transport_generic_allocate_tasks(se_cmd, sc->cmnd);
 151         if (ret != 0)
 152                 return ret;
 153         /*
 154          * For BIDI commands, pass in the extra READ buffer
 155          * to transport_generic_map_mem_to_cmd() below..
 156          */
 157         if (se_cmd->t_tasks_bidi) {
 158                 struct scsi_data_buffer *sdb = scsi_in(sc);
 159
 160                 sgl_bidi = sdb->table.sgl;
 161                 sgl_bidi_count = sdb->table.nents;
 162         }
 163         /*
 164          * Because some userspace code via scsi-generic do not memset their
 165          * associated read buffers, go ahead and do that here for type
 166          * SCF_SCSI_CONTROL_SG_IO_CDB.  Also note that this is currently
 167          * guaranteed to be a single SGL for SCF_SCSI_CONTROL_SG_IO_CDB
 168          * by target core in transport_generic_allocate_tasks() ->
 169          * transport_generic_cmd_sequencer().
 170          */
 171         if (se_cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB &&
 172             se_cmd->data_direction == DMA_FROM_DEVICE) {
 173                 struct scatterlist *sg = scsi_sglist(sc);
 174                 unsigned char *buf = kmap(sg_page(sg)) + sg->offset;
 175
 176                 if (buf != NULL) {
 177                         memset(buf, 0, sg->length);
 178                         kunmap(sg_page(sg));
 179                 }
 180         }
 181
 182         /* Tell the core about our preallocated memory */
 183         return transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),
 184                         scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);
 185 }
 186
 187 /*
 188  * Called from struct target_core_fabric_ops->check_stop_free()
 189  */
 190 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
 191 {
 192         /*
 193          * Do not release struct se_cmd's containing a valid TMR
 194          * pointer.  These will be released directly in tcm_loop_device_reset()
 195          * with transport_generic_free_cmd().
 196          */
 197         if (se_cmd->se_tmr_req)
 198                 return 0;
 199         /*
 200          * Release the struct se_cmd, which will make a callback to release
 201          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
 202          */
 203         transport_generic_free_cmd(se_cmd, 0);
 204         return 1;
 205 }
 206
 207 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
 208 {
 209         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 210                                 struct tcm_loop_cmd, tl_se_cmd);
 211
 212         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 213 }
 214
 215 static int tcm_loop_proc_info(struct Scsi_Host *host, char *buffer,
 216                                 char **start, off_t offset,
 217                                 int length, int inout)
 218 {
 219         return sprintf(buffer, "tcm_loop_proc_info()\n");
 220 }
 221
 222 static int tcm_loop_driver_probe(struct device *);
 223 static int tcm_loop_driver_remove(struct device *);
 224
 225 static int pseudo_lld_bus_match(struct device *dev,
 226                                 struct device_driver *dev_driver)
 227 {
 228         return 1;
 229 }
 230
 231 static struct bus_type tcm_loop_lld_bus = {
 232         .name                   = "tcm_loop_bus",
 233         .match                  = pseudo_lld_bus_match,
 234         .probe                  = tcm_loop_driver_probe,
 235         .remove                 = tcm_loop_driver_remove,
 236 };
 237
 238 static struct device_driver tcm_loop_driverfs = {
 239         .name                   = "tcm_loop",
 240         .bus                    = &tcm_loop_lld_bus,
 241 };
 242 /*
 243  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 244  */
 245 struct device *tcm_loop_primary;
 246
 247 /*
 248  * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
 249  * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
 250  */
 251 static int tcm_loop_change_queue_depth(
 252         struct scsi_device *sdev,
 253         int depth,
 254         int reason)
 255 {
 256         switch (reason) {
 257         case SCSI_QDEPTH_DEFAULT:
 258                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 259                 break;
 260         case SCSI_QDEPTH_QFULL:
 261                 scsi_track_queue_full(sdev, depth);
 262                 break;
 263         case SCSI_QDEPTH_RAMP_UP:
 264                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 265                 break;
 266         default:
 267                 return -EOPNOTSUPP;
 268         }
 269         return sdev->queue_depth;
 270 }
 271
 272 /*
 273  * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data
 274  * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs)
 275  */
 276 static int tcm_loop_queuecommand(
 277         struct Scsi_Host *sh,
 278         struct scsi_cmnd *sc)
 279 {
 280         struct se_cmd *se_cmd;
 281         struct se_portal_group *se_tpg;
 282         struct tcm_loop_hba *tl_hba;
 283         struct tcm_loop_tpg *tl_tpg;
 284
 285         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
 286                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 287                 sc->device->id, sc->device->channel, sc->device->lun,
 288                 sc->cmnd[0], scsi_bufflen(sc));
 289         /*
 290          * Locate the tcm_loop_hba_t pointer
 291          */
 292         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 293         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 294         /*
 295          * Ensure that this tl_tpg reference from the incoming sc->device->id
 296          * has already been configured via tcm_loop_make_naa_tpg().
 297          */
 298         if (!tl_tpg->tl_hba) {
 299                 set_host_byte(sc, DID_NO_CONNECT);
 300                 sc->scsi_done(sc);
 301                 return 0;
 302         }
 303         se_tpg = &tl_tpg->tl_se_tpg;
 304         /*
 305          * Determine the SAM Task Attribute and allocate tl_cmd and
 306          * tl_cmd->tl_se_cmd from TCM infrastructure
 307          */
 308         se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
 309         if (!se_cmd) {
 310                 sc->scsi_done(sc);
 311                 return 0;
 312         }
 313         /*
 314          * Queue up the newly allocated to be processed in TCM thread context.
 315         */
 316         transport_generic_handle_cdb_map(se_cmd);
 317         return 0;
 318 }
 319
 320 /*
 321  * Called from SCSI EH process context to issue a LUN_RESET TMR
 322  * to struct scsi_device
 323  */
 324 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 325 {
 326         struct se_cmd *se_cmd = NULL;
 327         struct se_portal_group *se_tpg;
 328         struct se_session *se_sess;
 329         struct tcm_loop_cmd *tl_cmd = NULL;
 330         struct tcm_loop_hba *tl_hba;
 331         struct tcm_loop_nexus *tl_nexus;
 332         struct tcm_loop_tmr *tl_tmr = NULL;
 333         struct tcm_loop_tpg *tl_tpg;
 334         int ret = FAILED;
 335         /*
 336          * Locate the tcm_loop_hba_t pointer
 337          */
 338         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 339         /*
 340          * Locate the tl_nexus and se_sess pointers
 341          */
 342         tl_nexus = tl_hba->tl_nexus;
 343         if (!tl_nexus) {
 344                 pr_err("Unable to perform device reset without"
 345                                 " active I_T Nexus\n");
 346                 return FAILED;
 347         }
 348         se_sess = tl_nexus->se_sess;
 349         /*
 350          * Locate the tl_tpg and se_tpg pointers from TargetID in sc->device->id
 351          */
 352         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 353         se_tpg = &tl_tpg->tl_se_tpg;
 354
 355         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 356         if (!tl_cmd) {
 357                 pr_err("Unable to allocate memory for tl_cmd\n");
 358                 return FAILED;
 359         }
 360
 361         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 362         if (!tl_tmr) {
 363                 pr_err("Unable to allocate memory for tl_tmr\n");
 364                 goto release;
 365         }
 366         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 367
 368         se_cmd = &tl_cmd->tl_se_cmd;
 369         /*
 370          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 371          */
 372         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 373                                 DMA_NONE, MSG_SIMPLE_TAG,
 374                                 &tl_cmd->tl_sense_buf[0]);
 375         /*
 376          * Allocate the LUN_RESET TMR
 377          */
 378         se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, tl_tmr,
 379                                                 TMR_LUN_RESET, GFP_KERNEL);
 380         if (IS_ERR(se_cmd->se_tmr_req))
 381                 goto release;
 382         /*
 383          * Locate the underlying TCM struct se_lun from sc->device->lun
 384          */
 385         if (transport_lookup_tmr_lun(se_cmd, sc->device->lun) < 0)
 386                 goto release;
 387         /*
 388          * Queue the TMR to TCM Core and sleep waiting for tcm_loop_queue_tm_rsp()
 389          * to wake us up.
 390          */
 391         transport_generic_handle_tmr(se_cmd);
 392         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 393         /*
 394          * The TMR LUN_RESET has completed, check the response status and
 395          * then release allocations.
 396          */
 397         ret = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
 398                 SUCCESS : FAILED;
 399 release:
 400         if (se_cmd)
 401                 transport_generic_free_cmd(se_cmd, 1);
 402         else
 403                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 404         kfree(tl_tmr);
 405         return ret;
 406 }
 407
 408 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 409 {
 410         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 411         return 0;
 412 }
 413
 414 static int tcm_loop_slave_configure(struct scsi_device *sd)
 415 {
 416         return 0;
 417 }
 418
 419 static struct scsi_host_template tcm_loop_driver_template = {
 420         .proc_info              = tcm_loop_proc_info,
 421         .proc_name              = "tcm_loopback",
 422         .name                   = "TCM_Loopback",
 423         .queuecommand           = tcm_loop_queuecommand,
 424         .change_queue_depth     = tcm_loop_change_queue_depth,
 425         .eh_device_reset_handler = tcm_loop_device_reset,
 426         .can_queue              = TL_SCSI_CAN_QUEUE,
 427         .this_id                = -1,
 428         .sg_tablesize           = TL_SCSI_SG_TABLESIZE,
 429         .cmd_per_lun            = TL_SCSI_CMD_PER_LUN,
 430         .max_sectors            = TL_SCSI_MAX_SECTORS,
 431         .use_clustering         = DISABLE_CLUSTERING,
 432         .slave_alloc            = tcm_loop_slave_alloc,
 433         .slave_configure        = tcm_loop_slave_configure,
 434         .module                 = THIS_MODULE,
 435 };
 436
 437 static int tcm_loop_driver_probe(struct device *dev)
 438 {
 439         struct tcm_loop_hba *tl_hba;
 440         struct Scsi_Host *sh;
 441         int error;
 442
 443         tl_hba = to_tcm_loop_hba(dev);
 444
 445         sh = scsi_host_alloc(&tcm_loop_driver_template,
 446                         sizeof(struct tcm_loop_hba));
 447         if (!sh) {
 448                 pr_err("Unable to allocate struct scsi_host\n");
 449                 return -ENODEV;
 450         }
 451         tl_hba->sh = sh;
 452
 453         /*
 454          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 455          */
 456         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 457         /*
 458          * Setup single ID, Channel and LUN for now..
 459          */
 460         sh->max_id = 2;
 461         sh->max_lun = 0;
 462         sh->max_channel = 0;
 463         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 464
 465         error = scsi_add_host(sh, &tl_hba->dev);
 466         if (error) {
 467                 pr_err("%s: scsi_add_host failed\n", __func__);
 468                 scsi_host_put(sh);
 469                 return -ENODEV;
 470         }
 471         return 0;
 472 }
 473
 474 static int tcm_loop_driver_remove(struct device *dev)
 475 {
 476         struct tcm_loop_hba *tl_hba;
 477         struct Scsi_Host *sh;
 478
 479         tl_hba = to_tcm_loop_hba(dev);
 480         sh = tl_hba->sh;
 481
 482         scsi_remove_host(sh);
 483         scsi_host_put(sh);
 484         return 0;
 485 }
 486
 487 static void tcm_loop_release_adapter(struct device *dev)
 488 {
 489         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 490
 491         kfree(tl_hba);
 492 }
 493
 494 /*
 495  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 496  */
 497 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 498 {
 499         int ret;
 500
 501         tl_hba->dev.bus = &tcm_loop_lld_bus;
 502         tl_hba->dev.parent = tcm_loop_primary;
 503         tl_hba->dev.release = &tcm_loop_release_adapter;
 504         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 505
 506         ret = device_register(&tl_hba->dev);
 507         if (ret) {
 508                 pr_err("device_register() failed for"
 509                                 " tl_hba->dev: %d\n", ret);
 510                 return -ENODEV;
 511         }
 512
 513         return 0;
 514 }
 515
 516 /*
 517  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 518  * tcm_loop SCSI bus.
 519  */
 520 static int tcm_loop_alloc_core_bus(void)
 521 {
 522         int ret;
 523
 524         tcm_loop_primary = root_device_register("tcm_loop_0");
 525         if (IS_ERR(tcm_loop_primary)) {
 526                 pr_err("Unable to allocate tcm_loop_primary\n");
 527                 return PTR_ERR(tcm_loop_primary);
 528         }
 529
 530         ret = bus_register(&tcm_loop_lld_bus);
 531         if (ret) {
 532                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 533                 goto dev_unreg;
 534         }
 535
 536         ret = driver_register(&tcm_loop_driverfs);
 537         if (ret) {
 538                 pr_err("driver_register() failed for"
 539                                 "tcm_loop_driverfs\n");
 540                 goto bus_unreg;
 541         }
 542
 543         pr_debug("Initialized TCM Loop Core Bus\n");
 544         return ret;
 545
 546 bus_unreg:
 547         bus_unregister(&tcm_loop_lld_bus);
 548 dev_unreg:
 549         root_device_unregister(tcm_loop_primary);
 550         return ret;
 551 }
 552
 553 static void tcm_loop_release_core_bus(void)
 554 {
 555         driver_unregister(&tcm_loop_driverfs);
 556         bus_unregister(&tcm_loop_lld_bus);
 557         root_device_unregister(tcm_loop_primary);
 558
 559         pr_debug("Releasing TCM Loop Core BUS\n");
 560 }
 561
 562 static char *tcm_loop_get_fabric_name(void)
 563 {
 564         return "loopback";
 565 }
 566
 567 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 568 {
 569         struct tcm_loop_tpg *tl_tpg =
 570                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 571         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 572         /*
 573          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 574          * time based on the protocol dependent prefix of the passed configfs group.
 575          *
 576          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 577          * ProtocolID using target_core_fabric_lib.c symbols.
 578          */
 579         switch (tl_hba->tl_proto_id) {
 580         case SCSI_PROTOCOL_SAS:
 581                 return sas_get_fabric_proto_ident(se_tpg);
 582         case SCSI_PROTOCOL_FCP:
 583                 return fc_get_fabric_proto_ident(se_tpg);
 584         case SCSI_PROTOCOL_ISCSI:
 585                 return iscsi_get_fabric_proto_ident(se_tpg);
 586         default:
 587                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 588                         " SAS emulation\n", tl_hba->tl_proto_id);
 589                 break;
 590         }
 591
 592         return sas_get_fabric_proto_ident(se_tpg);
 593 }
 594
 595 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 596 {
 597         struct tcm_loop_tpg *tl_tpg =
 598                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 599         /*
 600          * Return the passed NAA identifier for the SAS Target Port
 601          */
 602         return &tl_tpg->tl_hba->tl_wwn_address[0];
 603 }
 604
 605 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 606 {
 607         struct tcm_loop_tpg *tl_tpg =
 608                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 609         /*
 610          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 611          * to represent the SCSI Target Port.
 612          */
 613         return tl_tpg->tl_tpgt;
 614 }
 615
 616 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 617 {
 618         return 1;
 619 }
 620
 621 static u32 tcm_loop_get_pr_transport_id(
 622         struct se_portal_group *se_tpg,
 623         struct se_node_acl *se_nacl,
 624         struct t10_pr_registration *pr_reg,
 625         int *format_code,
 626         unsigned char *buf)
 627 {
 628         struct tcm_loop_tpg *tl_tpg =
 629                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 630         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 631
 632         switch (tl_hba->tl_proto_id) {
 633         case SCSI_PROTOCOL_SAS:
 634                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 635                                         format_code, buf);
 636         case SCSI_PROTOCOL_FCP:
 637                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 638                                         format_code, buf);
 639         case SCSI_PROTOCOL_ISCSI:
 640                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 641                                         format_code, buf);
 642         default:
 643                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 644                         " SAS emulation\n", tl_hba->tl_proto_id);
 645                 break;
 646         }
 647
 648         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 649                         format_code, buf);
 650 }
 651
 652 static u32 tcm_loop_get_pr_transport_id_len(
 653         struct se_portal_group *se_tpg,
 654         struct se_node_acl *se_nacl,
 655         struct t10_pr_registration *pr_reg,
 656         int *format_code)
 657 {
 658         struct tcm_loop_tpg *tl_tpg =
 659                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 660         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 661
 662         switch (tl_hba->tl_proto_id) {
 663         case SCSI_PROTOCOL_SAS:
 664                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 665                                         format_code);
 666         case SCSI_PROTOCOL_FCP:
 667                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 668                                         format_code);
 669         case SCSI_PROTOCOL_ISCSI:
 670                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 671                                         format_code);
 672         default:
 673                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 674                         " SAS emulation\n", tl_hba->tl_proto_id);
 675                 break;
 676         }
 677
 678         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 679                         format_code);
 680 }
 681
 682 /*
 683  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 684  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 685  */
 686 static char *tcm_loop_parse_pr_out_transport_id(
 687         struct se_portal_group *se_tpg,
 688         const char *buf,
 689         u32 *out_tid_len,
 690         char **port_nexus_ptr)
 691 {
 692         struct tcm_loop_tpg *tl_tpg =
 693                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 694         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 695
 696         switch (tl_hba->tl_proto_id) {
 697         case SCSI_PROTOCOL_SAS:
 698                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 699                                         port_nexus_ptr);
 700         case SCSI_PROTOCOL_FCP:
 701                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 702                                         port_nexus_ptr);
 703         case SCSI_PROTOCOL_ISCSI:
 704                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 705                                         port_nexus_ptr);
 706         default:
 707                 pr_err("Unknown tl_proto_id: 0x%02x, using"
 708                         " SAS emulation\n", tl_hba->tl_proto_id);
 709                 break;
 710         }
 711
 712         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 713                         port_nexus_ptr);
 714 }
 715
 716 /*
 717  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 718  * based upon the incoming fabric dependent SCSI Initiator Port
 719  */
 720 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 721 {
 722         return 1;
 723 }
 724
 725 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 726 {
 727         return 0;
 728 }
 729
 730 /*
 731  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 732  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 733  */
 734 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 735 {
 736         return 0;
 737 }
 738
 739 /*
 740  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 741  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 742  * It has been added here as a nop for target_fabric_tf_ops_check()
 743  */
 744 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 745 {
 746         return 0;
 747 }
 748
 749 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 750         struct se_portal_group *se_tpg)
 751 {
 752         struct tcm_loop_nacl *tl_nacl;
 753
 754         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 755         if (!tl_nacl) {
 756                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
 757                 return NULL;
 758         }
 759
 760         return &tl_nacl->se_node_acl;
 761 }
 762
 763 static void tcm_loop_tpg_release_fabric_acl(
 764         struct se_portal_group *se_tpg,
 765         struct se_node_acl *se_nacl)
 766 {
 767         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 768                                 struct tcm_loop_nacl, se_node_acl);
 769
 770         kfree(tl_nacl);
 771 }
 772
 773 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 774 {
 775         return 1;
 776 }
 777
 778 static int tcm_loop_is_state_remove(struct se_cmd *se_cmd)
 779 {
 780         /*
 781          * Assume struct scsi_cmnd is not in remove state..
 782          */
 783         return 0;
 784 }
 785
 786 static int tcm_loop_sess_logged_in(struct se_session *se_sess)
 787 {
 788         /*
 789          * Assume that TL Nexus is always active
 790          */
 791         return 1;
 792 }
 793
 794 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 795 {
 796         return 1;
 797 }
 798
 799 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 800 {
 801         return;
 802 }
 803
 804 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 805 {
 806         return 1;
 807 }
 808
 809 static int tcm_loop_get_cmd_state(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
 814         return tl_cmd->sc_cmd_state;
 815 }
 816
 817 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 818 {
 819         return 0;
 820 }
 821
 822 static void tcm_loop_close_session(struct se_session *se_sess)
 823 {
 824         return;
 825 };
 826
 827 static void tcm_loop_stop_session(
 828         struct se_session *se_sess,
 829         int sess_sleep,
 830         int conn_sleep)
 831 {
 832         return;
 833 }
 834
 835 static void tcm_loop_fall_back_to_erl0(struct se_session *se_sess)
 836 {
 837         return;
 838 }
 839
 840 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 841 {
 842         /*
 843          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 844          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 845          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 846          * format with transport_generic_map_mem_to_cmd().
 847          *
 848          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 849          * object execution queue.
 850          */
 851         transport_generic_process_write(se_cmd);
 852         return 0;
 853 }
 854
 855 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 856 {
 857         return 0;
 858 }
 859
 860 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 861 {
 862         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 863                                 struct tcm_loop_cmd, tl_se_cmd);
 864         struct scsi_cmnd *sc = tl_cmd->sc;
 865
 866         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 867                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 868
 869         sc->result = SAM_STAT_GOOD;
 870         set_host_byte(sc, DID_OK);
 871         sc->scsi_done(sc);
 872         return 0;
 873 }
 874
 875 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 876 {
 877         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 878                                 struct tcm_loop_cmd, tl_se_cmd);
 879         struct scsi_cmnd *sc = tl_cmd->sc;
 880
 881         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 882                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 883
 884         if (se_cmd->sense_buffer &&
 885            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 886             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 887
 888                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 889                                 SCSI_SENSE_BUFFERSIZE);
 890                 sc->result = SAM_STAT_CHECK_CONDITION;
 891                 set_driver_byte(sc, DRIVER_SENSE);
 892         } else
 893                 sc->result = se_cmd->scsi_status;
 894
 895         set_host_byte(sc, DID_OK);
 896         sc->scsi_done(sc);
 897         return 0;
 898 }
 899
 900 static int tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 901 {
 902         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 903         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 904         /*
 905          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 906          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 907          */
 908         atomic_set(&tl_tmr->tmr_complete, 1);
 909         wake_up(&tl_tmr->tl_tmr_wait);
 910         return 0;
 911 }
 912
 913 static u16 tcm_loop_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_length)
 914 {
 915         return 0;
 916 }
 917
 918 static u16 tcm_loop_get_fabric_sense_len(void)
 919 {
 920         return 0;
 921 }
 922
 923 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 924 {
 925         switch (tl_hba->tl_proto_id) {
 926         case SCSI_PROTOCOL_SAS:
 927                 return "SAS";
 928         case SCSI_PROTOCOL_FCP:
 929                 return "FCP";
 930         case SCSI_PROTOCOL_ISCSI:
 931                 return "iSCSI";
 932         default:
 933                 break;
 934         }
 935
 936         return "Unknown";
 937 }
 938
 939 /* Start items for tcm_loop_port_cit */
 940
 941 static int tcm_loop_port_link(
 942         struct se_portal_group *se_tpg,
 943         struct se_lun *lun)
 944 {
 945         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 946                                 struct tcm_loop_tpg, tl_se_tpg);
 947         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 948
 949         atomic_inc(&tl_tpg->tl_tpg_port_count);
 950         smp_mb__after_atomic_inc();
 951         /*
 952          * Add Linux/SCSI struct scsi_device by HCTL
 953          */
 954         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 955
 956         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 957         return 0;
 958 }
 959
 960 static void tcm_loop_port_unlink(
 961         struct se_portal_group *se_tpg,
 962         struct se_lun *se_lun)
 963 {
 964         struct scsi_device *sd;
 965         struct tcm_loop_hba *tl_hba;
 966         struct tcm_loop_tpg *tl_tpg;
 967
 968         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 969         tl_hba = tl_tpg->tl_hba;
 970
 971         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 972                                 se_lun->unpacked_lun);
 973         if (!sd) {
 974                 pr_err("Unable to locate struct scsi_device for %d:%d:"
 975                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 976                 return;
 977         }
 978         /*
 979          * Remove Linux/SCSI struct scsi_device by HCTL
 980          */
 981         scsi_remove_device(sd);
 982         scsi_device_put(sd);
 983
 984         atomic_dec(&tl_tpg->tl_tpg_port_count);
 985         smp_mb__after_atomic_dec();
 986
 987         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 988 }
 989
 990 /* End items for tcm_loop_port_cit */
 991
 992 /* Start items for tcm_loop_nexus_cit */
 993
 994 static int tcm_loop_make_nexus(
 995         struct tcm_loop_tpg *tl_tpg,
 996         const char *name)
 997 {
 998         struct se_portal_group *se_tpg;
 999         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1000         struct tcm_loop_nexus *tl_nexus;
1001         int ret = -ENOMEM;
1002
1003         if (tl_tpg->tl_hba->tl_nexus) {
1004                 pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
1005                 return -EEXIST;
1006         }
1007         se_tpg = &tl_tpg->tl_se_tpg;
1008
1009         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
1010         if (!tl_nexus) {
1011                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
1012                 return -ENOMEM;
1013         }
1014         /*
1015          * Initialize the struct se_session pointer
1016          */
1017         tl_nexus->se_sess = transport_init_session();
1018         if (IS_ERR(tl_nexus->se_sess)) {
1019                 ret = PTR_ERR(tl_nexus->se_sess);
1020                 goto out;
1021         }
1022         /*
1023          * Since we are running in 'demo mode' this call with generate a
1024          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
1025          * Initiator port name of the passed configfs group 'name'.
1026          */
1027         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1028                                 se_tpg, (unsigned char *)name);
1029         if (!tl_nexus->se_sess->se_node_acl) {
1030                 transport_free_session(tl_nexus->se_sess);
1031                 goto out;
1032         }
1033         /*
1034          * Now, register the SAS I_T Nexus as active with the call to
1035          * transport_register_session()
1036          */
1037         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1038                         tl_nexus->se_sess, tl_nexus);
1039         tl_tpg->tl_hba->tl_nexus = tl_nexus;
1040         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1041                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1042                 name);
1043         return 0;
1044
1045 out:
1046         kfree(tl_nexus);
1047         return ret;
1048 }
1049
1050 static int tcm_loop_drop_nexus(
1051         struct tcm_loop_tpg *tpg)
1052 {
1053         struct se_session *se_sess;
1054         struct tcm_loop_nexus *tl_nexus;
1055         struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1056
1057         tl_nexus = tpg->tl_hba->tl_nexus;
1058         if (!tl_nexus)
1059                 return -ENODEV;
1060
1061         se_sess = tl_nexus->se_sess;
1062         if (!se_sess)
1063                 return -ENODEV;
1064
1065         if (atomic_read(&tpg->tl_tpg_port_count)) {
1066                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
1067                         " active TPG port count: %d\n",
1068                         atomic_read(&tpg->tl_tpg_port_count));
1069                 return -EPERM;
1070         }
1071
1072         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1073                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1074                 tl_nexus->se_sess->se_node_acl->initiatorname);
1075         /*
1076          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1077          */
1078         transport_deregister_session(tl_nexus->se_sess);
1079         tpg->tl_hba->tl_nexus = NULL;
1080         kfree(tl_nexus);
1081         return 0;
1082 }
1083
1084 /* End items for tcm_loop_nexus_cit */
1085
1086 static ssize_t tcm_loop_tpg_show_nexus(
1087         struct se_portal_group *se_tpg,
1088         char *page)
1089 {
1090         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1091                         struct tcm_loop_tpg, tl_se_tpg);
1092         struct tcm_loop_nexus *tl_nexus;
1093         ssize_t ret;
1094
1095         tl_nexus = tl_tpg->tl_hba->tl_nexus;
1096         if (!tl_nexus)
1097                 return -ENODEV;
1098
1099         ret = snprintf(page, PAGE_SIZE, "%s\n",
1100                 tl_nexus->se_sess->se_node_acl->initiatorname);
1101
1102         return ret;
1103 }
1104
1105 static ssize_t tcm_loop_tpg_store_nexus(
1106         struct se_portal_group *se_tpg,
1107         const char *page,
1108         size_t count)
1109 {
1110         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1111                         struct tcm_loop_tpg, tl_se_tpg);
1112         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1113         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1114         int ret;
1115         /*
1116          * Shutdown the active I_T nexus if 'NULL' is passed..
1117          */
1118         if (!strncmp(page, "NULL", 4)) {
1119                 ret = tcm_loop_drop_nexus(tl_tpg);
1120                 return (!ret) ? count : ret;
1121         }
1122         /*
1123          * Otherwise make sure the passed virtual Initiator port WWN matches
1124          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1125          * tcm_loop_make_nexus()
1126          */
1127         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1128                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1129                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1130                 return -EINVAL;
1131         }
1132         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1133
1134         ptr = strstr(i_port, "naa.");
1135         if (ptr) {
1136                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1137                         pr_err("Passed SAS Initiator Port %s does not"
1138                                 " match target port protoid: %s\n", i_port,
1139                                 tcm_loop_dump_proto_id(tl_hba));
1140                         return -EINVAL;
1141                 }
1142                 port_ptr = &i_port[0];
1143                 goto check_newline;
1144         }
1145         ptr = strstr(i_port, "fc.");
1146         if (ptr) {
1147                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1148                         pr_err("Passed FCP Initiator Port %s does not"
1149                                 " match target port protoid: %s\n", i_port,
1150                                 tcm_loop_dump_proto_id(tl_hba));
1151                         return -EINVAL;
1152                 }
1153                 port_ptr = &i_port[3]; /* Skip over "fc." */
1154                 goto check_newline;
1155         }
1156         ptr = strstr(i_port, "iqn.");
1157         if (ptr) {
1158                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1159                         pr_err("Passed iSCSI Initiator Port %s does not"
1160                                 " match target port protoid: %s\n", i_port,
1161                                 tcm_loop_dump_proto_id(tl_hba));
1162                         return -EINVAL;
1163                 }
1164                 port_ptr = &i_port[0];
1165                 goto check_newline;
1166         }
1167         pr_err("Unable to locate prefix for emulated Initiator Port:"
1168                         " %s\n", i_port);
1169         return -EINVAL;
1170         /*
1171          * Clear any trailing newline for the NAA WWN
1172          */
1173 check_newline:
1174         if (i_port[strlen(i_port)-1] == '\n')
1175                 i_port[strlen(i_port)-1] = '\0';
1176
1177         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1178         if (ret < 0)
1179                 return ret;
1180
1181         return count;
1182 }
1183
1184 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1185
1186 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1187         &tcm_loop_tpg_nexus.attr,
1188         NULL,
1189 };
1190
1191 /* Start items for tcm_loop_naa_cit */
1192
1193 struct se_portal_group *tcm_loop_make_naa_tpg(
1194         struct se_wwn *wwn,
1195         struct config_group *group,
1196         const char *name)
1197 {
1198         struct tcm_loop_hba *tl_hba = container_of(wwn,
1199                         struct tcm_loop_hba, tl_hba_wwn);
1200         struct tcm_loop_tpg *tl_tpg;
1201         char *tpgt_str, *end_ptr;
1202         int ret;
1203         unsigned short int tpgt;
1204
1205         tpgt_str = strstr(name, "tpgt_");
1206         if (!tpgt_str) {
1207                 pr_err("Unable to locate \"tpgt_#\" directory"
1208                                 " group\n");
1209                 return ERR_PTR(-EINVAL);
1210         }
1211         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1212         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1213
1214         if (tpgt >= TL_TPGS_PER_HBA) {
1215                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1216                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1217                 return ERR_PTR(-EINVAL);
1218         }
1219         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1220         tl_tpg->tl_hba = tl_hba;
1221         tl_tpg->tl_tpgt = tpgt;
1222         /*
1223          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1224          */
1225         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1226                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1227                         TRANSPORT_TPG_TYPE_NORMAL);
1228         if (ret < 0)
1229                 return ERR_PTR(-ENOMEM);
1230
1231         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1232                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1233                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1234
1235         return &tl_tpg->tl_se_tpg;
1236 }
1237
1238 void tcm_loop_drop_naa_tpg(
1239         struct se_portal_group *se_tpg)
1240 {
1241         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1242         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1243                                 struct tcm_loop_tpg, tl_se_tpg);
1244         struct tcm_loop_hba *tl_hba;
1245         unsigned short tpgt;
1246
1247         tl_hba = tl_tpg->tl_hba;
1248         tpgt = tl_tpg->tl_tpgt;
1249         /*
1250          * Release the I_T Nexus for the Virtual SAS link if present
1251          */
1252         tcm_loop_drop_nexus(tl_tpg);
1253         /*
1254          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1255          */
1256         core_tpg_deregister(se_tpg);
1257
1258         tl_tpg->tl_hba = NULL;
1259         tl_tpg->tl_tpgt = 0;
1260
1261         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1262                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1263                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1264 }
1265
1266 /* End items for tcm_loop_naa_cit */
1267
1268 /* Start items for tcm_loop_cit */
1269
1270 struct se_wwn *tcm_loop_make_scsi_hba(
1271         struct target_fabric_configfs *tf,
1272         struct config_group *group,
1273         const char *name)
1274 {
1275         struct tcm_loop_hba *tl_hba;
1276         struct Scsi_Host *sh;
1277         char *ptr;
1278         int ret, off = 0;
1279
1280         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1281         if (!tl_hba) {
1282                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1283                 return ERR_PTR(-ENOMEM);
1284         }
1285         /*
1286          * Determine the emulated Protocol Identifier and Target Port Name
1287          * based on the incoming configfs directory name.
1288          */
1289         ptr = strstr(name, "naa.");
1290         if (ptr) {
1291                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1292                 goto check_len;
1293         }
1294         ptr = strstr(name, "fc.");
1295         if (ptr) {
1296                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1297                 off = 3; /* Skip over "fc." */
1298                 goto check_len;
1299         }
1300         ptr = strstr(name, "iqn.");
1301         if (!ptr) {
1302                 pr_err("Unable to locate prefix for emulated Target "
1303                                 "Port: %s\n", name);
1304                 ret = -EINVAL;
1305                 goto out;
1306         }
1307         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1308
1309 check_len:
1310         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1311                 pr_err("Emulated NAA %s Address: %s, exceeds"
1312                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1313                         TL_WWN_ADDR_LEN);
1314                 ret = -EINVAL;
1315                 goto out;
1316         }
1317         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1318
1319         /*
1320          * Call device_register(tl_hba->dev) to register the emulated
1321          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1322          * device_register() callbacks in tcm_loop_driver_probe()
1323          */
1324         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1325         if (ret)
1326                 goto out;
1327
1328         sh = tl_hba->sh;
1329         tcm_loop_hba_no_cnt++;
1330         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1331                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1332                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1333
1334         return &tl_hba->tl_hba_wwn;
1335 out:
1336         kfree(tl_hba);
1337         return ERR_PTR(ret);
1338 }
1339
1340 void tcm_loop_drop_scsi_hba(
1341         struct se_wwn *wwn)
1342 {
1343         struct tcm_loop_hba *tl_hba = container_of(wwn,
1344                                 struct tcm_loop_hba, tl_hba_wwn);
1345         int host_no = tl_hba->sh->host_no;
1346         /*
1347          * Call device_unregister() on the original tl_hba->dev.
1348          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1349          * release *tl_hba;
1350          */
1351         device_unregister(&tl_hba->dev);
1352
1353         pr_debug("TCM_Loop_ConfigFS: Deallocated emulated Target"
1354                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1355                 config_item_name(&wwn->wwn_group.cg_item), host_no);
1356 }
1357
1358 /* Start items for tcm_loop_cit */
1359 static ssize_t tcm_loop_wwn_show_attr_version(
1360         struct target_fabric_configfs *tf,
1361         char *page)
1362 {
1363         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1364 }
1365
1366 TF_WWN_ATTR_RO(tcm_loop, version);
1367
1368 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1369         &tcm_loop_wwn_version.attr,
1370         NULL,
1371 };
1372
1373 /* End items for tcm_loop_cit */
1374
1375 static int tcm_loop_register_configfs(void)
1376 {
1377         struct target_fabric_configfs *fabric;
1378         struct config_group *tf_cg;
1379         int ret;
1380         /*
1381          * Set the TCM Loop HBA counter to zero
1382          */
1383         tcm_loop_hba_no_cnt = 0;
1384         /*
1385          * Register the top level struct config_item_type with TCM core
1386          */
1387         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1388         if (IS_ERR(fabric)) {
1389                 pr_err("tcm_loop_register_configfs() failed!\n");
1390                 return PTR_ERR(fabric);
1391         }
1392         /*
1393          * Setup the fabric API of function pointers used by target_core_mod
1394          */
1395         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1396         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1397         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1398         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1399         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1400         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1401         fabric->tf_ops.tpg_get_pr_transport_id_len =
1402                                         &tcm_loop_get_pr_transport_id_len;
1403         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1404                                         &tcm_loop_parse_pr_out_transport_id;
1405         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1406         fabric->tf_ops.tpg_check_demo_mode_cache =
1407                                         &tcm_loop_check_demo_mode_cache;
1408         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1409                                         &tcm_loop_check_demo_mode_write_protect;
1410         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1411                                         &tcm_loop_check_prod_mode_write_protect;
1412         /*
1413          * The TCM loopback fabric module runs in demo-mode to a local
1414          * virtual SCSI device, so fabric dependent initator ACLs are
1415          * not required.
1416          */
1417         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1418         fabric->tf_ops.tpg_release_fabric_acl =
1419                                         &tcm_loop_tpg_release_fabric_acl;
1420         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1421         /*
1422          * Used for setting up remaining TCM resources in process context
1423          */
1424         fabric->tf_ops.new_cmd_map = &tcm_loop_new_cmd_map;
1425         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1426         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1427         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1428         fabric->tf_ops.close_session = &tcm_loop_close_session;
1429         fabric->tf_ops.stop_session = &tcm_loop_stop_session;
1430         fabric->tf_ops.fall_back_to_erl0 = &tcm_loop_fall_back_to_erl0;
1431         fabric->tf_ops.sess_logged_in = &tcm_loop_sess_logged_in;
1432         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1433         fabric->tf_ops.sess_get_initiator_sid = NULL;
1434         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1435         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1436         /*
1437          * Not used for TCM loopback
1438          */
1439         fabric->tf_ops.set_default_node_attributes =
1440                                         &tcm_loop_set_default_node_attributes;
1441         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1442         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1443         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1444         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1445         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1446         fabric->tf_ops.set_fabric_sense_len = &tcm_loop_set_fabric_sense_len;
1447         fabric->tf_ops.get_fabric_sense_len = &tcm_loop_get_fabric_sense_len;
1448         fabric->tf_ops.is_state_remove = &tcm_loop_is_state_remove;
1449
1450         tf_cg = &fabric->tf_group;
1451         /*
1452          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1453          */
1454         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1455         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1456         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1457         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1458         /*
1459          * fabric_post_link() and fabric_pre_unlink() are used for
1460          * registration and release of TCM Loop Virtual SCSI LUNs.
1461          */
1462         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1463         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1464         fabric->tf_ops.fabric_make_np = NULL;
1465         fabric->tf_ops.fabric_drop_np = NULL;
1466         /*
1467          * Setup default attribute lists for various fabric->tf_cit_tmpl
1468          */
1469         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1470         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1471         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1472         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1473         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1474         /*
1475          * Once fabric->tf_ops has been setup, now register the fabric for
1476          * use within TCM
1477          */
1478         ret = target_fabric_configfs_register(fabric);
1479         if (ret < 0) {
1480                 pr_err("target_fabric_configfs_register() for"
1481                                 " TCM_Loop failed!\n");
1482                 target_fabric_configfs_free(fabric);
1483                 return -1;
1484         }
1485         /*
1486          * Setup our local pointer to *fabric.
1487          */
1488         tcm_loop_fabric_configfs = fabric;
1489         pr_debug("TCM_LOOP[0] - Set fabric ->"
1490                         " tcm_loop_fabric_configfs\n");
1491         return 0;
1492 }
1493
1494 static void tcm_loop_deregister_configfs(void)
1495 {
1496         if (!tcm_loop_fabric_configfs)
1497                 return;
1498
1499         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1500         tcm_loop_fabric_configfs = NULL;
1501         pr_debug("TCM_LOOP[0] - Cleared"
1502                                 " tcm_loop_fabric_configfs\n");
1503 }
1504
1505 static int __init tcm_loop_fabric_init(void)
1506 {
1507         int ret;
1508
1509         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1510                                 sizeof(struct tcm_loop_cmd),
1511                                 __alignof__(struct tcm_loop_cmd),
1512                                 0, NULL);
1513         if (!tcm_loop_cmd_cache) {
1514                 pr_debug("kmem_cache_create() for"
1515                         " tcm_loop_cmd_cache failed\n");
1516                 return -ENOMEM;
1517         }
1518
1519         ret = tcm_loop_alloc_core_bus();
1520         if (ret)
1521                 return ret;
1522
1523         ret = tcm_loop_register_configfs();
1524         if (ret) {
1525                 tcm_loop_release_core_bus();
1526                 return ret;
1527         }
1528
1529         return 0;
1530 }
1531
1532 static void __exit tcm_loop_fabric_exit(void)
1533 {
1534         tcm_loop_deregister_configfs();
1535         tcm_loop_release_core_bus();
1536         kmem_cache_destroy(tcm_loop_cmd_cache);
1537 }
1538
1539 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1540 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1541 MODULE_LICENSE("GPL");
1542 module_init(tcm_loop_fabric_init);
1543 module_exit(tcm_loop_fabric_exit);