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 #include <scsi/scsi_tcq.h>
  35
  36 #include <target/target_core_base.h>
  37 #include <target/target_core_transport.h>
  38 #include <target/target_core_fabric_ops.h>
  39 #include <target/target_core_fabric_configfs.h>
  40 #include <target/target_core_fabric_lib.h>
  41 #include <target/target_core_configfs.h>
  42 #include <target/target_core_device.h>
  43 #include <target/target_core_tpg.h>
  44 #include <target/target_core_tmr.h>
  45
  46 #include "tcm_loop.h"
  47
  48 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
  49
  50 /* Local pointer to allocated TCM configfs fabric module */
  51 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  52
  53 static struct kmem_cache *tcm_loop_cmd_cache;
  54
  55 static int tcm_loop_hba_no_cnt;
  56
  57 /*
  58  * Allocate a tcm_loop cmd descriptor from target_core_mod code
  59  *
  60  * Can be called from interrupt context in tcm_loop_queuecommand() below
  61  */
  62 static struct se_cmd *tcm_loop_allocate_core_cmd(
  63         struct tcm_loop_hba *tl_hba,
  64         struct se_portal_group *se_tpg,
  65         struct scsi_cmnd *sc)
  66 {
  67         struct se_cmd *se_cmd;
  68         struct se_session *se_sess;
  69         struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus;
  70         struct tcm_loop_cmd *tl_cmd;
  71         int sam_task_attr;
  72
  73         if (!tl_nexus) {
  74                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
  75                                 " does not exist\n");
  76                 set_host_byte(sc, DID_ERROR);
  77                 return NULL;
  78         }
  79         se_sess = tl_nexus->se_sess;
  80
  81         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
  82         if (!tl_cmd) {
  83                 printk(KERN_ERR "Unable to allocate struct tcm_loop_cmd\n");
  84                 set_host_byte(sc, DID_ERROR);
  85                 return NULL;
  86         }
  87         se_cmd = &tl_cmd->tl_se_cmd;
  88         /*
  89          * Save the pointer to struct scsi_cmnd *sc
  90          */
  91         tl_cmd->sc = sc;
  92         /*
  93          * Locate the SAM Task Attr from struct scsi_cmnd *
  94          */
  95         if (sc->device->tagged_supported) {
  96                 switch (sc->tag) {
  97                 case HEAD_OF_QUEUE_TAG:
  98                         sam_task_attr = MSG_HEAD_TAG;
  99                         break;
 100                 case ORDERED_QUEUE_TAG:
 101                         sam_task_attr = MSG_ORDERED_TAG;
 102                         break;
 103                 default:
 104                         sam_task_attr = MSG_SIMPLE_TAG;
 105                         break;
 106                 }
 107         } else
 108                 sam_task_attr = MSG_SIMPLE_TAG;
 109
 110         /*
 111          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 112          */
 113         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
 114                         scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr,
 115                         &tl_cmd->tl_sense_buf[0]);
 116
 117         /*
 118          * Signal BIDI usage with T_TASK(cmd)->t_tasks_bidi
 119          */
 120         if (scsi_bidi_cmnd(sc))
 121                 T_TASK(se_cmd)->t_tasks_bidi = 1;
 122         /*
 123          * Locate the struct se_lun pointer and attach it to struct se_cmd
 124          */
 125         if (transport_get_lun_for_cmd(se_cmd, NULL, tl_cmd->sc->device->lun) < 0) {
 126                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 127                 set_host_byte(sc, DID_NO_CONNECT);
 128                 return NULL;
 129         }
 130
 131         transport_device_setup_cmd(se_cmd);
 132         return se_cmd;
 133 }
 134
 135 /*
 136  * Called by struct target_core_fabric_ops->new_cmd_map()
 137  *
 138  * Always called in process context.  A non zero return value
 139  * here will signal to handle an exception based on the return code.
 140  */
 141 static int tcm_loop_new_cmd_map(struct se_cmd *se_cmd)
 142 {
 143         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 144                                 struct tcm_loop_cmd, tl_se_cmd);
 145         struct scsi_cmnd *sc = tl_cmd->sc;
 146         void *mem_ptr, *mem_bidi_ptr = NULL;
 147         u32 sg_no_bidi = 0;
 148         int ret;
 149         /*
 150          * Allocate the necessary tasks to complete the received CDB+data
 151          */
 152         ret = transport_generic_allocate_tasks(se_cmd, tl_cmd->sc->cmnd);
 153         if (ret == -1) {
 154                 /* Out of Resources */
 155                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 156         } else if (ret == -2) {
 157                 /*
 158                  * Handle case for SAM_STAT_RESERVATION_CONFLICT
 159                  */
 160                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
 161                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
 162                 /*
 163                  * Otherwise, return SAM_STAT_CHECK_CONDITION and return
 164                  * sense data.
 165                  */
 166                 return PYX_TRANSPORT_USE_SENSE_REASON;
 167         }
 168         /*
 169          * Setup the struct scatterlist memory from the received
 170          * struct scsi_cmnd.
 171          */
 172         if (scsi_sg_count(sc)) {
 173                 se_cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM;
 174                 mem_ptr = (void *)scsi_sglist(sc);
 175                 /*
 176                  * For BIDI commands, pass in the extra READ buffer
 177                  * to transport_generic_map_mem_to_cmd() below..
 178                  */
 179                 if (T_TASK(se_cmd)->t_tasks_bidi) {
 180                         struct scsi_data_buffer *sdb = scsi_in(sc);
 181
 182                         mem_bidi_ptr = (void *)sdb->table.sgl;
 183                         sg_no_bidi = sdb->table.nents;
 184                 }
 185         } else {
 186                 /*
 187                  * Used for DMA_NONE
 188                  */
 189                 mem_ptr = NULL;
 190         }
 191         /*
 192          * Map the SG memory into struct se_mem->page linked list using the same
 193          * physical memory at sg->page_link.
 194          */
 195         ret = transport_generic_map_mem_to_cmd(se_cmd, mem_ptr,
 196                         scsi_sg_count(sc), mem_bidi_ptr, sg_no_bidi);
 197         if (ret < 0)
 198                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 199
 200         return 0;
 201 }
 202
 203 /*
 204  * Called from struct target_core_fabric_ops->check_stop_free()
 205  */
 206 static void tcm_loop_check_stop_free(struct se_cmd *se_cmd)
 207 {
 208         /*
 209          * Do not release struct se_cmd's containing a valid TMR
 210          * pointer.  These will be released directly in tcm_loop_device_reset()
 211          * with transport_generic_free_cmd().
 212          */
 213         if (se_cmd->se_tmr_req)
 214                 return;
 215         /*
 216          * Release the struct se_cmd, which will make a callback to release
 217          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
 218          */
 219         transport_generic_free_cmd(se_cmd, 0, 1, 0);
 220 }
 221
 222 /*
 223  * Called from struct target_core_fabric_ops->release_cmd_to_pool()
 224  */
 225 static void tcm_loop_deallocate_core_cmd(struct se_cmd *se_cmd)
 226 {
 227         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 228                                 struct tcm_loop_cmd, tl_se_cmd);
 229
 230         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 231 }
 232
 233 static int tcm_loop_proc_info(struct Scsi_Host *host, char *buffer,
 234                                 char **start, off_t offset,
 235                                 int length, int inout)
 236 {
 237         return sprintf(buffer, "tcm_loop_proc_info()\n");
 238 }
 239
 240 static int tcm_loop_driver_probe(struct device *);
 241 static int tcm_loop_driver_remove(struct device *);
 242
 243 static int pseudo_lld_bus_match(struct device *dev,
 244                                 struct device_driver *dev_driver)
 245 {
 246         return 1;
 247 }
 248
 249 static struct bus_type tcm_loop_lld_bus = {
 250         .name                   = "tcm_loop_bus",
 251         .match                  = pseudo_lld_bus_match,
 252         .probe                  = tcm_loop_driver_probe,
 253         .remove                 = tcm_loop_driver_remove,
 254 };
 255
 256 static struct device_driver tcm_loop_driverfs = {
 257         .name                   = "tcm_loop",
 258         .bus                    = &tcm_loop_lld_bus,
 259 };
 260 /*
 261  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 262  */
 263 struct device *tcm_loop_primary;
 264
 265 /*
 266  * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
 267  * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
 268  */
 269 static int tcm_loop_change_queue_depth(
 270         struct scsi_device *sdev,
 271         int depth,
 272         int reason)
 273 {
 274         switch (reason) {
 275         case SCSI_QDEPTH_DEFAULT:
 276                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 277                 break;
 278         case SCSI_QDEPTH_QFULL:
 279                 scsi_track_queue_full(sdev, depth);
 280                 break;
 281         case SCSI_QDEPTH_RAMP_UP:
 282                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 283                 break;
 284         default:
 285                 return -EOPNOTSUPP;
 286         }
 287         return sdev->queue_depth;
 288 }
 289
 290 /*
 291  * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data
 292  * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs)
 293  */
 294 static int tcm_loop_queuecommand(
 295         struct Scsi_Host *sh,
 296         struct scsi_cmnd *sc)
 297 {
 298         struct se_cmd *se_cmd;
 299         struct se_portal_group *se_tpg;
 300         struct tcm_loop_hba *tl_hba;
 301         struct tcm_loop_tpg *tl_tpg;
 302
 303         TL_CDB_DEBUG("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
 304                 " scsi_buf_len: %u\n", sc->device->host->host_no,
 305                 sc->device->id, sc->device->channel, sc->device->lun,
 306                 sc->cmnd[0], scsi_bufflen(sc));
 307         /*
 308          * Locate the tcm_loop_hba_t pointer
 309          */
 310         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 311         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 312         se_tpg = &tl_tpg->tl_se_tpg;
 313         /*
 314          * Determine the SAM Task Attribute and allocate tl_cmd and
 315          * tl_cmd->tl_se_cmd from TCM infrastructure
 316          */
 317         se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
 318         if (!se_cmd) {
 319                 sc->scsi_done(sc);
 320                 return 0;
 321         }
 322         /*
 323          * Queue up the newly allocated to be processed in TCM thread context.
 324         */
 325         transport_generic_handle_cdb_map(se_cmd);
 326         return 0;
 327 }
 328
 329 /*
 330  * Called from SCSI EH process context to issue a LUN_RESET TMR
 331  * to struct scsi_device
 332  */
 333 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 334 {
 335         struct se_cmd *se_cmd = NULL;
 336         struct se_portal_group *se_tpg;
 337         struct se_session *se_sess;
 338         struct tcm_loop_cmd *tl_cmd = NULL;
 339         struct tcm_loop_hba *tl_hba;
 340         struct tcm_loop_nexus *tl_nexus;
 341         struct tcm_loop_tmr *tl_tmr = NULL;
 342         struct tcm_loop_tpg *tl_tpg;
 343         int ret = FAILED;
 344         /*
 345          * Locate the tcm_loop_hba_t pointer
 346          */
 347         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 348         /*
 349          * Locate the tl_nexus and se_sess pointers
 350          */
 351         tl_nexus = tl_hba->tl_nexus;
 352         if (!tl_nexus) {
 353                 printk(KERN_ERR "Unable to perform device reset without"
 354                                 " active I_T Nexus\n");
 355                 return FAILED;
 356         }
 357         se_sess = tl_nexus->se_sess;
 358         /*
 359          * Locate the tl_tpg and se_tpg pointers from TargetID in sc->device->id
 360          */
 361         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 362         se_tpg = &tl_tpg->tl_se_tpg;
 363
 364         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 365         if (!tl_cmd) {
 366                 printk(KERN_ERR "Unable to allocate memory for tl_cmd\n");
 367                 return FAILED;
 368         }
 369
 370         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 371         if (!tl_tmr) {
 372                 printk(KERN_ERR "Unable to allocate memory for tl_tmr\n");
 373                 goto release;
 374         }
 375         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 376
 377         se_cmd = &tl_cmd->tl_se_cmd;
 378         /*
 379          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 380          */
 381         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 382                                 DMA_NONE, MSG_SIMPLE_TAG,
 383                                 &tl_cmd->tl_sense_buf[0]);
 384         /*
 385          * Allocate the LUN_RESET TMR
 386          */
 387         se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, (void *)tl_tmr,
 388                                 TMR_LUN_RESET);
 389         if (IS_ERR(se_cmd->se_tmr_req))
 390                 goto release;
 391         /*
 392          * Locate the underlying TCM struct se_lun from sc->device->lun
 393          */
 394         if (transport_get_lun_for_tmr(se_cmd, sc->device->lun) < 0)
 395                 goto release;
 396         /*
 397          * Queue the TMR to TCM Core and sleep waiting for tcm_loop_queue_tm_rsp()
 398          * to wake us up.
 399          */
 400         transport_generic_handle_tmr(se_cmd);
 401         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 402         /*
 403          * The TMR LUN_RESET has completed, check the response status and
 404          * then release allocations.
 405          */
 406         ret = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
 407                 SUCCESS : FAILED;
 408 release:
 409         if (se_cmd)
 410                 transport_generic_free_cmd(se_cmd, 1, 1, 0);
 411         else
 412                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 413         kfree(tl_tmr);
 414         return ret;
 415 }
 416
 417 static int tcm_loop_slave_alloc(struct scsi_device *sd)
 418 {
 419         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 420         return 0;
 421 }
 422
 423 static int tcm_loop_slave_configure(struct scsi_device *sd)
 424 {
 425         return 0;
 426 }
 427
 428 static struct scsi_host_template tcm_loop_driver_template = {
 429         .proc_info              = tcm_loop_proc_info,
 430         .proc_name              = "tcm_loopback",
 431         .name                   = "TCM_Loopback",
 432         .queuecommand           = tcm_loop_queuecommand,
 433         .change_queue_depth     = tcm_loop_change_queue_depth,
 434         .eh_device_reset_handler = tcm_loop_device_reset,
 435         .can_queue              = TL_SCSI_CAN_QUEUE,
 436         .this_id                = -1,
 437         .sg_tablesize           = TL_SCSI_SG_TABLESIZE,
 438         .cmd_per_lun            = TL_SCSI_CMD_PER_LUN,
 439         .max_sectors            = TL_SCSI_MAX_SECTORS,
 440         .use_clustering         = DISABLE_CLUSTERING,
 441         .slave_alloc            = tcm_loop_slave_alloc,
 442         .slave_configure        = tcm_loop_slave_configure,
 443         .module                 = THIS_MODULE,
 444 };
 445
 446 static int tcm_loop_driver_probe(struct device *dev)
 447 {
 448         struct tcm_loop_hba *tl_hba;
 449         struct Scsi_Host *sh;
 450         int error;
 451
 452         tl_hba = to_tcm_loop_hba(dev);
 453
 454         sh = scsi_host_alloc(&tcm_loop_driver_template,
 455                         sizeof(struct tcm_loop_hba));
 456         if (!sh) {
 457                 printk(KERN_ERR "Unable to allocate struct scsi_host\n");
 458                 return -ENODEV;
 459         }
 460         tl_hba->sh = sh;
 461
 462         /*
 463          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 464          */
 465         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 466         /*
 467          * Setup single ID, Channel and LUN for now..
 468          */
 469         sh->max_id = 2;
 470         sh->max_lun = 0;
 471         sh->max_channel = 0;
 472         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 473
 474         error = scsi_add_host(sh, &tl_hba->dev);
 475         if (error) {
 476                 printk(KERN_ERR "%s: scsi_add_host failed\n", __func__);
 477                 scsi_host_put(sh);
 478                 return -ENODEV;
 479         }
 480         return 0;
 481 }
 482
 483 static int tcm_loop_driver_remove(struct device *dev)
 484 {
 485         struct tcm_loop_hba *tl_hba;
 486         struct Scsi_Host *sh;
 487
 488         tl_hba = to_tcm_loop_hba(dev);
 489         sh = tl_hba->sh;
 490
 491         scsi_remove_host(sh);
 492         scsi_host_put(sh);
 493         return 0;
 494 }
 495
 496 static void tcm_loop_release_adapter(struct device *dev)
 497 {
 498         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 499
 500         kfree(tl_hba);
 501 }
 502
 503 /*
 504  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 505  */
 506 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 507 {
 508         int ret;
 509
 510         tl_hba->dev.bus = &tcm_loop_lld_bus;
 511         tl_hba->dev.parent = tcm_loop_primary;
 512         tl_hba->dev.release = &tcm_loop_release_adapter;
 513         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 514
 515         ret = device_register(&tl_hba->dev);
 516         if (ret) {
 517                 printk(KERN_ERR "device_register() failed for"
 518                                 " tl_hba->dev: %d\n", ret);
 519                 return -ENODEV;
 520         }
 521
 522         return 0;
 523 }
 524
 525 /*
 526  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 527  * tcm_loop SCSI bus.
 528  */
 529 static int tcm_loop_alloc_core_bus(void)
 530 {
 531         int ret;
 532
 533         tcm_loop_primary = root_device_register("tcm_loop_0");
 534         if (IS_ERR(tcm_loop_primary)) {
 535                 printk(KERN_ERR "Unable to allocate tcm_loop_primary\n");
 536                 return PTR_ERR(tcm_loop_primary);
 537         }
 538
 539         ret = bus_register(&tcm_loop_lld_bus);
 540         if (ret) {
 541                 printk(KERN_ERR "bus_register() failed for tcm_loop_lld_bus\n");
 542                 goto dev_unreg;
 543         }
 544
 545         ret = driver_register(&tcm_loop_driverfs);
 546         if (ret) {
 547                 printk(KERN_ERR "driver_register() failed for"
 548                                 "tcm_loop_driverfs\n");
 549                 goto bus_unreg;
 550         }
 551
 552         printk(KERN_INFO "Initialized TCM Loop Core Bus\n");
 553         return ret;
 554
 555 bus_unreg:
 556         bus_unregister(&tcm_loop_lld_bus);
 557 dev_unreg:
 558         root_device_unregister(tcm_loop_primary);
 559         return ret;
 560 }
 561
 562 static void tcm_loop_release_core_bus(void)
 563 {
 564         driver_unregister(&tcm_loop_driverfs);
 565         bus_unregister(&tcm_loop_lld_bus);
 566         root_device_unregister(tcm_loop_primary);
 567
 568         printk(KERN_INFO "Releasing TCM Loop Core BUS\n");
 569 }
 570
 571 static char *tcm_loop_get_fabric_name(void)
 572 {
 573         return "loopback";
 574 }
 575
 576 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 577 {
 578         struct tcm_loop_tpg *tl_tpg =
 579                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 580         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 581         /*
 582          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 583          * time based on the protocol dependent prefix of the passed configfs group.
 584          *
 585          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 586          * ProtocolID using target_core_fabric_lib.c symbols.
 587          */
 588         switch (tl_hba->tl_proto_id) {
 589         case SCSI_PROTOCOL_SAS:
 590                 return sas_get_fabric_proto_ident(se_tpg);
 591         case SCSI_PROTOCOL_FCP:
 592                 return fc_get_fabric_proto_ident(se_tpg);
 593         case SCSI_PROTOCOL_ISCSI:
 594                 return iscsi_get_fabric_proto_ident(se_tpg);
 595         default:
 596                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
 597                         " SAS emulation\n", tl_hba->tl_proto_id);
 598                 break;
 599         }
 600
 601         return sas_get_fabric_proto_ident(se_tpg);
 602 }
 603
 604 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 605 {
 606         struct tcm_loop_tpg *tl_tpg =
 607                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 608         /*
 609          * Return the passed NAA identifier for the SAS Target Port
 610          */
 611         return &tl_tpg->tl_hba->tl_wwn_address[0];
 612 }
 613
 614 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 615 {
 616         struct tcm_loop_tpg *tl_tpg =
 617                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 618         /*
 619          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 620          * to represent the SCSI Target Port.
 621          */
 622         return tl_tpg->tl_tpgt;
 623 }
 624
 625 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 626 {
 627         return 1;
 628 }
 629
 630 static u32 tcm_loop_get_pr_transport_id(
 631         struct se_portal_group *se_tpg,
 632         struct se_node_acl *se_nacl,
 633         struct t10_pr_registration *pr_reg,
 634         int *format_code,
 635         unsigned char *buf)
 636 {
 637         struct tcm_loop_tpg *tl_tpg =
 638                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 639         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 640
 641         switch (tl_hba->tl_proto_id) {
 642         case SCSI_PROTOCOL_SAS:
 643                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 644                                         format_code, buf);
 645         case SCSI_PROTOCOL_FCP:
 646                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 647                                         format_code, buf);
 648         case SCSI_PROTOCOL_ISCSI:
 649                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 650                                         format_code, buf);
 651         default:
 652                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
 653                         " SAS emulation\n", tl_hba->tl_proto_id);
 654                 break;
 655         }
 656
 657         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 658                         format_code, buf);
 659 }
 660
 661 static u32 tcm_loop_get_pr_transport_id_len(
 662         struct se_portal_group *se_tpg,
 663         struct se_node_acl *se_nacl,
 664         struct t10_pr_registration *pr_reg,
 665         int *format_code)
 666 {
 667         struct tcm_loop_tpg *tl_tpg =
 668                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 669         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 670
 671         switch (tl_hba->tl_proto_id) {
 672         case SCSI_PROTOCOL_SAS:
 673                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 674                                         format_code);
 675         case SCSI_PROTOCOL_FCP:
 676                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 677                                         format_code);
 678         case SCSI_PROTOCOL_ISCSI:
 679                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 680                                         format_code);
 681         default:
 682                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
 683                         " SAS emulation\n", tl_hba->tl_proto_id);
 684                 break;
 685         }
 686
 687         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 688                         format_code);
 689 }
 690
 691 /*
 692  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 693  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 694  */
 695 static char *tcm_loop_parse_pr_out_transport_id(
 696         struct se_portal_group *se_tpg,
 697         const char *buf,
 698         u32 *out_tid_len,
 699         char **port_nexus_ptr)
 700 {
 701         struct tcm_loop_tpg *tl_tpg =
 702                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 703         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 704
 705         switch (tl_hba->tl_proto_id) {
 706         case SCSI_PROTOCOL_SAS:
 707                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 708                                         port_nexus_ptr);
 709         case SCSI_PROTOCOL_FCP:
 710                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 711                                         port_nexus_ptr);
 712         case SCSI_PROTOCOL_ISCSI:
 713                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 714                                         port_nexus_ptr);
 715         default:
 716                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
 717                         " SAS emulation\n", tl_hba->tl_proto_id);
 718                 break;
 719         }
 720
 721         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 722                         port_nexus_ptr);
 723 }
 724
 725 /*
 726  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 727  * based upon the incoming fabric dependent SCSI Initiator Port
 728  */
 729 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 730 {
 731         return 1;
 732 }
 733
 734 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 735 {
 736         return 0;
 737 }
 738
 739 /*
 740  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 741  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 742  */
 743 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 744 {
 745         return 0;
 746 }
 747
 748 /*
 749  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 750  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 751  * It has been added here as a nop for target_fabric_tf_ops_check()
 752  */
 753 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 754 {
 755         return 0;
 756 }
 757
 758 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 759         struct se_portal_group *se_tpg)
 760 {
 761         struct tcm_loop_nacl *tl_nacl;
 762
 763         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 764         if (!tl_nacl) {
 765                 printk(KERN_ERR "Unable to allocate struct tcm_loop_nacl\n");
 766                 return NULL;
 767         }
 768
 769         return &tl_nacl->se_node_acl;
 770 }
 771
 772 static void tcm_loop_tpg_release_fabric_acl(
 773         struct se_portal_group *se_tpg,
 774         struct se_node_acl *se_nacl)
 775 {
 776         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 777                                 struct tcm_loop_nacl, se_node_acl);
 778
 779         kfree(tl_nacl);
 780 }
 781
 782 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 783 {
 784         return 1;
 785 }
 786
 787 static void tcm_loop_new_cmd_failure(struct se_cmd *se_cmd)
 788 {
 789         /*
 790          * Since TCM_loop is already passing struct scatterlist data from
 791          * struct scsi_cmnd, no more Linux/SCSI failure dependent state need
 792          * to be handled here.
 793          */
 794         return;
 795 }
 796
 797 static int tcm_loop_is_state_remove(struct se_cmd *se_cmd)
 798 {
 799         /*
 800          * Assume struct scsi_cmnd is not in remove state..
 801          */
 802         return 0;
 803 }
 804
 805 static int tcm_loop_sess_logged_in(struct se_session *se_sess)
 806 {
 807         /*
 808          * Assume that TL Nexus is always active
 809          */
 810         return 1;
 811 }
 812
 813 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 814 {
 815         return 1;
 816 }
 817
 818 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 819 {
 820         return;
 821 }
 822
 823 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 824 {
 825         return 1;
 826 }
 827
 828 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 829 {
 830         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 831                         struct tcm_loop_cmd, tl_se_cmd);
 832
 833         return tl_cmd->sc_cmd_state;
 834 }
 835
 836 static int tcm_loop_shutdown_session(struct se_session *se_sess)
 837 {
 838         return 0;
 839 }
 840
 841 static void tcm_loop_close_session(struct se_session *se_sess)
 842 {
 843         return;
 844 };
 845
 846 static void tcm_loop_stop_session(
 847         struct se_session *se_sess,
 848         int sess_sleep,
 849         int conn_sleep)
 850 {
 851         return;
 852 }
 853
 854 static void tcm_loop_fall_back_to_erl0(struct se_session *se_sess)
 855 {
 856         return;
 857 }
 858
 859 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 860 {
 861         /*
 862          * Since Linux/SCSI has already sent down a struct scsi_cmnd
 863          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 864          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 865          * format with transport_generic_map_mem_to_cmd().
 866          *
 867          * We now tell TCM to add this WRITE CDB directly into the TCM storage
 868          * object execution queue.
 869          */
 870         transport_generic_process_write(se_cmd);
 871         return 0;
 872 }
 873
 874 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 875 {
 876         return 0;
 877 }
 878
 879 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 880 {
 881         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 882                                 struct tcm_loop_cmd, tl_se_cmd);
 883         struct scsi_cmnd *sc = tl_cmd->sc;
 884
 885         TL_CDB_DEBUG("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 886                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 887
 888         sc->result = SAM_STAT_GOOD;
 889         set_host_byte(sc, DID_OK);
 890         sc->scsi_done(sc);
 891         return 0;
 892 }
 893
 894 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 895 {
 896         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 897                                 struct tcm_loop_cmd, tl_se_cmd);
 898         struct scsi_cmnd *sc = tl_cmd->sc;
 899
 900         TL_CDB_DEBUG("tcm_loop_queue_status() called for scsi_cmnd: %p"
 901                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 902
 903         if (se_cmd->sense_buffer &&
 904            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 905             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 906
 907                 memcpy((void *)sc->sense_buffer, (void *)se_cmd->sense_buffer,
 908                                 SCSI_SENSE_BUFFERSIZE);
 909                 sc->result = SAM_STAT_CHECK_CONDITION;
 910                 set_driver_byte(sc, DRIVER_SENSE);
 911         } else
 912                 sc->result = se_cmd->scsi_status;
 913
 914         set_host_byte(sc, DID_OK);
 915         sc->scsi_done(sc);
 916         return 0;
 917 }
 918
 919 static int tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 920 {
 921         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 922         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 923         /*
 924          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 925          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 926          */
 927         atomic_set(&tl_tmr->tmr_complete, 1);
 928         wake_up(&tl_tmr->tl_tmr_wait);
 929         return 0;
 930 }
 931
 932 static u16 tcm_loop_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_length)
 933 {
 934         return 0;
 935 }
 936
 937 static u16 tcm_loop_get_fabric_sense_len(void)
 938 {
 939         return 0;
 940 }
 941
 942 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 943 {
 944         switch (tl_hba->tl_proto_id) {
 945         case SCSI_PROTOCOL_SAS:
 946                 return "SAS";
 947         case SCSI_PROTOCOL_FCP:
 948                 return "FCP";
 949         case SCSI_PROTOCOL_ISCSI:
 950                 return "iSCSI";
 951         default:
 952                 break;
 953         }
 954
 955         return "Unknown";
 956 }
 957
 958 /* Start items for tcm_loop_port_cit */
 959
 960 static int tcm_loop_port_link(
 961         struct se_portal_group *se_tpg,
 962         struct se_lun *lun)
 963 {
 964         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 965                                 struct tcm_loop_tpg, tl_se_tpg);
 966         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 967
 968         atomic_inc(&tl_tpg->tl_tpg_port_count);
 969         smp_mb__after_atomic_inc();
 970         /*
 971          * Add Linux/SCSI struct scsi_device by HCTL
 972          */
 973         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 974
 975         printk(KERN_INFO "TCM_Loop_ConfigFS: Port Link Successful\n");
 976         return 0;
 977 }
 978
 979 static void tcm_loop_port_unlink(
 980         struct se_portal_group *se_tpg,
 981         struct se_lun *se_lun)
 982 {
 983         struct scsi_device *sd;
 984         struct tcm_loop_hba *tl_hba;
 985         struct tcm_loop_tpg *tl_tpg;
 986
 987         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 988         tl_hba = tl_tpg->tl_hba;
 989
 990         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 991                                 se_lun->unpacked_lun);
 992         if (!sd) {
 993                 printk(KERN_ERR "Unable to locate struct scsi_device for %d:%d:"
 994                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 995                 return;
 996         }
 997         /*
 998          * Remove Linux/SCSI struct scsi_device by HCTL
 999          */
1000         scsi_remove_device(sd);
1001         scsi_device_put(sd);
1002
1003         atomic_dec(&tl_tpg->tl_tpg_port_count);
1004         smp_mb__after_atomic_dec();
1005
1006         printk(KERN_INFO "TCM_Loop_ConfigFS: Port Unlink Successful\n");
1007 }
1008
1009 /* End items for tcm_loop_port_cit */
1010
1011 /* Start items for tcm_loop_nexus_cit */
1012
1013 static int tcm_loop_make_nexus(
1014         struct tcm_loop_tpg *tl_tpg,
1015         const char *name)
1016 {
1017         struct se_portal_group *se_tpg;
1018         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1019         struct tcm_loop_nexus *tl_nexus;
1020         int ret = -ENOMEM;
1021
1022         if (tl_tpg->tl_hba->tl_nexus) {
1023                 printk(KERN_INFO "tl_tpg->tl_hba->tl_nexus already exists\n");
1024                 return -EEXIST;
1025         }
1026         se_tpg = &tl_tpg->tl_se_tpg;
1027
1028         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
1029         if (!tl_nexus) {
1030                 printk(KERN_ERR "Unable to allocate struct tcm_loop_nexus\n");
1031                 return -ENOMEM;
1032         }
1033         /*
1034          * Initialize the struct se_session pointer
1035          */
1036         tl_nexus->se_sess = transport_init_session();
1037         if (IS_ERR(tl_nexus->se_sess)) {
1038                 ret = PTR_ERR(tl_nexus->se_sess);
1039                 goto out;
1040         }
1041         /*
1042          * Since we are running in 'demo mode' this call with generate a
1043          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
1044          * Initiator port name of the passed configfs group 'name'.
1045          */
1046         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1047                                 se_tpg, (unsigned char *)name);
1048         if (!tl_nexus->se_sess->se_node_acl) {
1049                 transport_free_session(tl_nexus->se_sess);
1050                 goto out;
1051         }
1052         /*
1053          * Now, register the SAS I_T Nexus as active with the call to
1054          * transport_register_session()
1055          */
1056         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1057                         tl_nexus->se_sess, (void *)tl_nexus);
1058         tl_tpg->tl_hba->tl_nexus = tl_nexus;
1059         printk(KERN_INFO "TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1060                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1061                 name);
1062         return 0;
1063
1064 out:
1065         kfree(tl_nexus);
1066         return ret;
1067 }
1068
1069 static int tcm_loop_drop_nexus(
1070         struct tcm_loop_tpg *tpg)
1071 {
1072         struct se_session *se_sess;
1073         struct tcm_loop_nexus *tl_nexus;
1074         struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1075
1076         tl_nexus = tpg->tl_hba->tl_nexus;
1077         if (!tl_nexus)
1078                 return -ENODEV;
1079
1080         se_sess = tl_nexus->se_sess;
1081         if (!se_sess)
1082                 return -ENODEV;
1083
1084         if (atomic_read(&tpg->tl_tpg_port_count)) {
1085                 printk(KERN_ERR "Unable to remove TCM_Loop I_T Nexus with"
1086                         " active TPG port count: %d\n",
1087                         atomic_read(&tpg->tl_tpg_port_count));
1088                 return -EPERM;
1089         }
1090
1091         printk(KERN_INFO "TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1092                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1093                 tl_nexus->se_sess->se_node_acl->initiatorname);
1094         /*
1095          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1096          */
1097         transport_deregister_session(tl_nexus->se_sess);
1098         tpg->tl_hba->tl_nexus = NULL;
1099         kfree(tl_nexus);
1100         return 0;
1101 }
1102
1103 /* End items for tcm_loop_nexus_cit */
1104
1105 static ssize_t tcm_loop_tpg_show_nexus(
1106         struct se_portal_group *se_tpg,
1107         char *page)
1108 {
1109         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1110                         struct tcm_loop_tpg, tl_se_tpg);
1111         struct tcm_loop_nexus *tl_nexus;
1112         ssize_t ret;
1113
1114         tl_nexus = tl_tpg->tl_hba->tl_nexus;
1115         if (!tl_nexus)
1116                 return -ENODEV;
1117
1118         ret = snprintf(page, PAGE_SIZE, "%s\n",
1119                 tl_nexus->se_sess->se_node_acl->initiatorname);
1120
1121         return ret;
1122 }
1123
1124 static ssize_t tcm_loop_tpg_store_nexus(
1125         struct se_portal_group *se_tpg,
1126         const char *page,
1127         size_t count)
1128 {
1129         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1130                         struct tcm_loop_tpg, tl_se_tpg);
1131         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1132         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1133         int ret;
1134         /*
1135          * Shutdown the active I_T nexus if 'NULL' is passed..
1136          */
1137         if (!strncmp(page, "NULL", 4)) {
1138                 ret = tcm_loop_drop_nexus(tl_tpg);
1139                 return (!ret) ? count : ret;
1140         }
1141         /*
1142          * Otherwise make sure the passed virtual Initiator port WWN matches
1143          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1144          * tcm_loop_make_nexus()
1145          */
1146         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1147                 printk(KERN_ERR "Emulated NAA Sas Address: %s, exceeds"
1148                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1149                 return -EINVAL;
1150         }
1151         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1152
1153         ptr = strstr(i_port, "naa.");
1154         if (ptr) {
1155                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1156                         printk(KERN_ERR "Passed SAS Initiator Port %s does not"
1157                                 " match target port protoid: %s\n", i_port,
1158                                 tcm_loop_dump_proto_id(tl_hba));
1159                         return -EINVAL;
1160                 }
1161                 port_ptr = &i_port[0];
1162                 goto check_newline;
1163         }
1164         ptr = strstr(i_port, "fc.");
1165         if (ptr) {
1166                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1167                         printk(KERN_ERR "Passed FCP Initiator Port %s does not"
1168                                 " match target port protoid: %s\n", i_port,
1169                                 tcm_loop_dump_proto_id(tl_hba));
1170                         return -EINVAL;
1171                 }
1172                 port_ptr = &i_port[3]; /* Skip over "fc." */
1173                 goto check_newline;
1174         }
1175         ptr = strstr(i_port, "iqn.");
1176         if (ptr) {
1177                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1178                         printk(KERN_ERR "Passed iSCSI Initiator Port %s does not"
1179                                 " match target port protoid: %s\n", i_port,
1180                                 tcm_loop_dump_proto_id(tl_hba));
1181                         return -EINVAL;
1182                 }
1183                 port_ptr = &i_port[0];
1184                 goto check_newline;
1185         }
1186         printk(KERN_ERR "Unable to locate prefix for emulated Initiator Port:"
1187                         " %s\n", i_port);
1188         return -EINVAL;
1189         /*
1190          * Clear any trailing newline for the NAA WWN
1191          */
1192 check_newline:
1193         if (i_port[strlen(i_port)-1] == '\n')
1194                 i_port[strlen(i_port)-1] = '\0';
1195
1196         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1197         if (ret < 0)
1198                 return ret;
1199
1200         return count;
1201 }
1202
1203 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1204
1205 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1206         &tcm_loop_tpg_nexus.attr,
1207         NULL,
1208 };
1209
1210 /* Start items for tcm_loop_naa_cit */
1211
1212 struct se_portal_group *tcm_loop_make_naa_tpg(
1213         struct se_wwn *wwn,
1214         struct config_group *group,
1215         const char *name)
1216 {
1217         struct tcm_loop_hba *tl_hba = container_of(wwn,
1218                         struct tcm_loop_hba, tl_hba_wwn);
1219         struct tcm_loop_tpg *tl_tpg;
1220         char *tpgt_str, *end_ptr;
1221         int ret;
1222         unsigned short int tpgt;
1223
1224         tpgt_str = strstr(name, "tpgt_");
1225         if (!tpgt_str) {
1226                 printk(KERN_ERR "Unable to locate \"tpgt_#\" directory"
1227                                 " group\n");
1228                 return ERR_PTR(-EINVAL);
1229         }
1230         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1231         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1232
1233         if (tpgt > TL_TPGS_PER_HBA) {
1234                 printk(KERN_ERR "Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1235                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1236                 return ERR_PTR(-EINVAL);
1237         }
1238         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1239         tl_tpg->tl_hba = tl_hba;
1240         tl_tpg->tl_tpgt = tpgt;
1241         /*
1242          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1243          */
1244         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1245                         wwn, &tl_tpg->tl_se_tpg, (void *)tl_tpg,
1246                         TRANSPORT_TPG_TYPE_NORMAL);
1247         if (ret < 0)
1248                 return ERR_PTR(-ENOMEM);
1249
1250         printk(KERN_INFO "TCM_Loop_ConfigFS: Allocated Emulated %s"
1251                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1252                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1253
1254         return &tl_tpg->tl_se_tpg;
1255 }
1256
1257 void tcm_loop_drop_naa_tpg(
1258         struct se_portal_group *se_tpg)
1259 {
1260         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1261         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1262                                 struct tcm_loop_tpg, tl_se_tpg);
1263         struct tcm_loop_hba *tl_hba;
1264         unsigned short tpgt;
1265
1266         tl_hba = tl_tpg->tl_hba;
1267         tpgt = tl_tpg->tl_tpgt;
1268         /*
1269          * Release the I_T Nexus for the Virtual SAS link if present
1270          */
1271         tcm_loop_drop_nexus(tl_tpg);
1272         /*
1273          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1274          */
1275         core_tpg_deregister(se_tpg);
1276
1277         printk(KERN_INFO "TCM_Loop_ConfigFS: Deallocated Emulated %s"
1278                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1279                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1280 }
1281
1282 /* End items for tcm_loop_naa_cit */
1283
1284 /* Start items for tcm_loop_cit */
1285
1286 struct se_wwn *tcm_loop_make_scsi_hba(
1287         struct target_fabric_configfs *tf,
1288         struct config_group *group,
1289         const char *name)
1290 {
1291         struct tcm_loop_hba *tl_hba;
1292         struct Scsi_Host *sh;
1293         char *ptr;
1294         int ret, off = 0;
1295
1296         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1297         if (!tl_hba) {
1298                 printk(KERN_ERR "Unable to allocate struct tcm_loop_hba\n");
1299                 return ERR_PTR(-ENOMEM);
1300         }
1301         /*
1302          * Determine the emulated Protocol Identifier and Target Port Name
1303          * based on the incoming configfs directory name.
1304          */
1305         ptr = strstr(name, "naa.");
1306         if (ptr) {
1307                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1308                 goto check_len;
1309         }
1310         ptr = strstr(name, "fc.");
1311         if (ptr) {
1312                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1313                 off = 3; /* Skip over "fc." */
1314                 goto check_len;
1315         }
1316         ptr = strstr(name, "iqn.");
1317         if (ptr) {
1318                 tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1319                 goto check_len;
1320         }
1321
1322         printk(KERN_ERR "Unable to locate prefix for emulated Target Port:"
1323                         " %s\n", name);
1324         return ERR_PTR(-EINVAL);
1325
1326 check_len:
1327         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1328                 printk(KERN_ERR "Emulated NAA %s Address: %s, exceeds"
1329                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1330                         TL_WWN_ADDR_LEN);
1331                 kfree(tl_hba);
1332                 return ERR_PTR(-EINVAL);
1333         }
1334         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1335
1336         /*
1337          * Call device_register(tl_hba->dev) to register the emulated
1338          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1339          * device_register() callbacks in tcm_loop_driver_probe()
1340          */
1341         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1342         if (ret)
1343                 goto out;
1344
1345         sh = tl_hba->sh;
1346         tcm_loop_hba_no_cnt++;
1347         printk(KERN_INFO "TCM_Loop_ConfigFS: Allocated emulated Target"
1348                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1349                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1350
1351         return &tl_hba->tl_hba_wwn;
1352 out:
1353         kfree(tl_hba);
1354         return ERR_PTR(ret);
1355 }
1356
1357 void tcm_loop_drop_scsi_hba(
1358         struct se_wwn *wwn)
1359 {
1360         struct tcm_loop_hba *tl_hba = container_of(wwn,
1361                                 struct tcm_loop_hba, tl_hba_wwn);
1362         int host_no = tl_hba->sh->host_no;
1363         /*
1364          * Call device_unregister() on the original tl_hba->dev.
1365          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1366          * release *tl_hba;
1367          */
1368         device_unregister(&tl_hba->dev);
1369
1370         printk(KERN_INFO "TCM_Loop_ConfigFS: Deallocated emulated Target"
1371                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1372                 config_item_name(&wwn->wwn_group.cg_item), host_no);
1373 }
1374
1375 /* Start items for tcm_loop_cit */
1376 static ssize_t tcm_loop_wwn_show_attr_version(
1377         struct target_fabric_configfs *tf,
1378         char *page)
1379 {
1380         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1381 }
1382
1383 TF_WWN_ATTR_RO(tcm_loop, version);
1384
1385 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1386         &tcm_loop_wwn_version.attr,
1387         NULL,
1388 };
1389
1390 /* End items for tcm_loop_cit */
1391
1392 static int tcm_loop_register_configfs(void)
1393 {
1394         struct target_fabric_configfs *fabric;
1395         struct config_group *tf_cg;
1396         int ret;
1397         /*
1398          * Set the TCM Loop HBA counter to zero
1399          */
1400         tcm_loop_hba_no_cnt = 0;
1401         /*
1402          * Register the top level struct config_item_type with TCM core
1403          */
1404         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1405         if (!fabric) {
1406                 printk(KERN_ERR "tcm_loop_register_configfs() failed!\n");
1407                 return -1;
1408         }
1409         /*
1410          * Setup the fabric API of function pointers used by target_core_mod
1411          */
1412         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1413         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1414         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1415         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1416         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1417         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1418         fabric->tf_ops.tpg_get_pr_transport_id_len =
1419                                         &tcm_loop_get_pr_transport_id_len;
1420         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1421                                         &tcm_loop_parse_pr_out_transport_id;
1422         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1423         fabric->tf_ops.tpg_check_demo_mode_cache =
1424                                         &tcm_loop_check_demo_mode_cache;
1425         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1426                                         &tcm_loop_check_demo_mode_write_protect;
1427         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1428                                         &tcm_loop_check_prod_mode_write_protect;
1429         /*
1430          * The TCM loopback fabric module runs in demo-mode to a local
1431          * virtual SCSI device, so fabric dependent initator ACLs are
1432          * not required.
1433          */
1434         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1435         fabric->tf_ops.tpg_release_fabric_acl =
1436                                         &tcm_loop_tpg_release_fabric_acl;
1437         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1438         /*
1439          * Since tcm_loop is mapping physical memory from Linux/SCSI
1440          * struct scatterlist arrays for each struct scsi_cmnd I/O,
1441          * we do not need TCM to allocate a iovec array for
1442          * virtual memory address mappings
1443          */
1444         fabric->tf_ops.alloc_cmd_iovecs = NULL;
1445         /*
1446          * Used for setting up remaining TCM resources in process context
1447          */
1448         fabric->tf_ops.new_cmd_map = &tcm_loop_new_cmd_map;
1449         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1450         fabric->tf_ops.release_cmd_to_pool = &tcm_loop_deallocate_core_cmd;
1451         fabric->tf_ops.release_cmd_direct = &tcm_loop_deallocate_core_cmd;
1452         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1453         fabric->tf_ops.close_session = &tcm_loop_close_session;
1454         fabric->tf_ops.stop_session = &tcm_loop_stop_session;
1455         fabric->tf_ops.fall_back_to_erl0 = &tcm_loop_fall_back_to_erl0;
1456         fabric->tf_ops.sess_logged_in = &tcm_loop_sess_logged_in;
1457         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1458         fabric->tf_ops.sess_get_initiator_sid = NULL;
1459         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1460         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1461         /*
1462          * Not used for TCM loopback
1463          */
1464         fabric->tf_ops.set_default_node_attributes =
1465                                         &tcm_loop_set_default_node_attributes;
1466         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1467         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1468         fabric->tf_ops.new_cmd_failure = &tcm_loop_new_cmd_failure;
1469         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1470         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1471         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1472         fabric->tf_ops.set_fabric_sense_len = &tcm_loop_set_fabric_sense_len;
1473         fabric->tf_ops.get_fabric_sense_len = &tcm_loop_get_fabric_sense_len;
1474         fabric->tf_ops.is_state_remove = &tcm_loop_is_state_remove;
1475
1476         tf_cg = &fabric->tf_group;
1477         /*
1478          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1479          */
1480         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1481         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1482         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1483         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1484         /*
1485          * fabric_post_link() and fabric_pre_unlink() are used for
1486          * registration and release of TCM Loop Virtual SCSI LUNs.
1487          */
1488         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1489         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1490         fabric->tf_ops.fabric_make_np = NULL;
1491         fabric->tf_ops.fabric_drop_np = NULL;
1492         /*
1493          * Setup default attribute lists for various fabric->tf_cit_tmpl
1494          */
1495         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1496         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1497         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1498         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1499         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1500         /*
1501          * Once fabric->tf_ops has been setup, now register the fabric for
1502          * use within TCM
1503          */
1504         ret = target_fabric_configfs_register(fabric);
1505         if (ret < 0) {
1506                 printk(KERN_ERR "target_fabric_configfs_register() for"
1507                                 " TCM_Loop failed!\n");
1508                 target_fabric_configfs_free(fabric);
1509                 return -1;
1510         }
1511         /*
1512          * Setup our local pointer to *fabric.
1513          */
1514         tcm_loop_fabric_configfs = fabric;
1515         printk(KERN_INFO "TCM_LOOP[0] - Set fabric ->"
1516                         " tcm_loop_fabric_configfs\n");
1517         return 0;
1518 }
1519
1520 static void tcm_loop_deregister_configfs(void)
1521 {
1522         if (!tcm_loop_fabric_configfs)
1523                 return;
1524
1525         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1526         tcm_loop_fabric_configfs = NULL;
1527         printk(KERN_INFO "TCM_LOOP[0] - Cleared"
1528                                 " tcm_loop_fabric_configfs\n");
1529 }
1530
1531 static int __init tcm_loop_fabric_init(void)
1532 {
1533         int ret;
1534
1535         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1536                                 sizeof(struct tcm_loop_cmd),
1537                                 __alignof__(struct tcm_loop_cmd),
1538                                 0, NULL);
1539         if (!tcm_loop_cmd_cache) {
1540                 printk(KERN_ERR "kmem_cache_create() for"
1541                         " tcm_loop_cmd_cache failed\n");
1542                 return -ENOMEM;
1543         }
1544
1545         ret = tcm_loop_alloc_core_bus();
1546         if (ret)
1547                 return ret;
1548
1549         ret = tcm_loop_register_configfs();
1550         if (ret) {
1551                 tcm_loop_release_core_bus();
1552                 return ret;
1553         }
1554
1555         return 0;
1556 }
1557
1558 static void __exit tcm_loop_fabric_exit(void)
1559 {
1560         tcm_loop_deregister_configfs();
1561         tcm_loop_release_core_bus();
1562         kmem_cache_destroy(tcm_loop_cmd_cache);
1563 }
1564
1565 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1566 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1567 MODULE_LICENSE("GPL");
1568 module_init(tcm_loop_fabric_init);
1569 module_exit(tcm_loop_fabric_exit);