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v5.9
   1/*******************************************************************************
   2 *
   3 * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4 * for emulated SAS initiator ports
   5 *
   6 * © Copyright 2011-2013 Datera, Inc.
   7 *
   8 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9 *
  10 * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 ****************************************************************************/
  22
  23#include <linux/module.h>
  24#include <linux/moduleparam.h>
  25#include <linux/init.h>
  26#include <linux/slab.h>
  27#include <linux/types.h>
  28#include <linux/configfs.h>
  29#include <scsi/scsi.h>
  30#include <scsi/scsi_tcq.h>
  31#include <scsi/scsi_host.h>
  32#include <scsi/scsi_device.h>
  33#include <scsi/scsi_cmnd.h>
  34
  35#include <target/target_core_base.h>
  36#include <target/target_core_fabric.h>
  37
  38#include "tcm_loop.h"
  39
  40#define to_tcm_loop_hba(hba)	container_of(hba, struct tcm_loop_hba, dev)
  41
  42static struct workqueue_struct *tcm_loop_workqueue;
  43static struct kmem_cache *tcm_loop_cmd_cache;
  44
  45static int tcm_loop_hba_no_cnt;
  46
  47static int tcm_loop_queue_status(struct se_cmd *se_cmd);
  48
 
 
 
 
 
 
 
 
 
  49/*
  50 * Called from struct target_core_fabric_ops->check_stop_free()
  51 */
  52static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  53{
  54	return transport_generic_free_cmd(se_cmd, 0);
  55}
  56
  57static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  58{
  59	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  60				struct tcm_loop_cmd, tl_se_cmd);
 
  61
  62	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 
 
 
  63}
  64
  65static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  66{
  67	seq_puts(m, "tcm_loop_proc_info()\n");
  68	return 0;
  69}
  70
  71static int tcm_loop_driver_probe(struct device *);
  72static int tcm_loop_driver_remove(struct device *);
  73
  74static int pseudo_lld_bus_match(struct device *dev,
  75				struct device_driver *dev_driver)
  76{
  77	return 1;
  78}
  79
  80static struct bus_type tcm_loop_lld_bus = {
  81	.name			= "tcm_loop_bus",
  82	.match			= pseudo_lld_bus_match,
  83	.probe			= tcm_loop_driver_probe,
  84	.remove			= tcm_loop_driver_remove,
  85};
  86
  87static struct device_driver tcm_loop_driverfs = {
  88	.name			= "tcm_loop",
  89	.bus			= &tcm_loop_lld_bus,
  90};
  91/*
  92 * Used with root_device_register() in tcm_loop_alloc_core_bus() below
  93 */
  94static struct device *tcm_loop_primary;
  95
  96static void tcm_loop_submission_work(struct work_struct *work)
  97{
  98	struct tcm_loop_cmd *tl_cmd =
  99		container_of(work, struct tcm_loop_cmd, work);
 100	struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 101	struct scsi_cmnd *sc = tl_cmd->sc;
 102	struct tcm_loop_nexus *tl_nexus;
 103	struct tcm_loop_hba *tl_hba;
 104	struct tcm_loop_tpg *tl_tpg;
 105	struct scatterlist *sgl_bidi = NULL;
 106	u32 sgl_bidi_count = 0, transfer_length;
 107	int rc;
 108
 109	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 110	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 111
 112	/*
 113	 * Ensure that this tl_tpg reference from the incoming sc->device->id
 114	 * has already been configured via tcm_loop_make_naa_tpg().
 115	 */
 116	if (!tl_tpg->tl_hba) {
 117		set_host_byte(sc, DID_NO_CONNECT);
 118		goto out_done;
 119	}
 120	if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 121		set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 122		goto out_done;
 123	}
 124	tl_nexus = tl_tpg->tl_nexus;
 125	if (!tl_nexus) {
 126		scmd_printk(KERN_ERR, sc,
 127			    "TCM_Loop I_T Nexus does not exist\n");
 128		set_host_byte(sc, DID_ERROR);
 129		goto out_done;
 130	}
 131
 132	transfer_length = scsi_transfer_length(sc);
 133	if (!scsi_prot_sg_count(sc) &&
 134	    scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 135		se_cmd->prot_pto = true;
 136		/*
 137		 * loopback transport doesn't support
 138		 * WRITE_GENERATE, READ_STRIP protection
 139		 * information operations, go ahead unprotected.
 140		 */
 141		transfer_length = scsi_bufflen(sc);
 142	}
 143
 144	se_cmd->tag = tl_cmd->sc_cmd_tag;
 145	rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
 146			&tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
 147			transfer_length, TCM_SIMPLE_TAG,
 148			sc->sc_data_direction, 0,
 149			scsi_sglist(sc), scsi_sg_count(sc),
 150			sgl_bidi, sgl_bidi_count,
 151			scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
 152	if (rc < 0) {
 153		set_host_byte(sc, DID_NO_CONNECT);
 154		goto out_done;
 155	}
 156	return;
 157
 158out_done:
 159	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 160	sc->scsi_done(sc);
 161}
 162
 163/*
 164 * ->queuecommand can be and usually is called from interrupt context, so
 165 * defer the actual submission to a workqueue.
 166 */
 167static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 168{
 169	struct tcm_loop_cmd *tl_cmd;
 170
 171	pr_debug("%s() %d:%d:%d:%llu got CDB: 0x%02x scsi_buf_len: %u\n",
 172		 __func__, sc->device->host->host_no, sc->device->id,
 173		 sc->device->channel, sc->device->lun, sc->cmnd[0],
 174		 scsi_bufflen(sc));
 175
 176	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 177	if (!tl_cmd) {
 178		set_host_byte(sc, DID_ERROR);
 179		sc->scsi_done(sc);
 180		return 0;
 181	}
 182
 183	tl_cmd->sc = sc;
 184	tl_cmd->sc_cmd_tag = sc->request->tag;
 185	INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 186	queue_work(tcm_loop_workqueue, &tl_cmd->work);
 187	return 0;
 188}
 189
 190/*
 191 * Called from SCSI EH process context to issue a LUN_RESET TMR
 192 * to struct scsi_device
 193 */
 194static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 195			      u64 lun, int task, enum tcm_tmreq_table tmr)
 196{
 197	struct se_cmd *se_cmd;
 198	struct se_session *se_sess;
 199	struct tcm_loop_nexus *tl_nexus;
 200	struct tcm_loop_cmd *tl_cmd;
 201	int ret = TMR_FUNCTION_FAILED, rc;
 202
 203	/*
 204	 * Locate the tl_nexus and se_sess pointers
 205	 */
 206	tl_nexus = tl_tpg->tl_nexus;
 207	if (!tl_nexus) {
 208		pr_err("Unable to perform device reset without active I_T Nexus\n");
 209		return ret;
 210	}
 211
 212	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 213	if (!tl_cmd)
 214		return ret;
 215
 216	init_completion(&tl_cmd->tmr_done);
 217
 218	se_cmd = &tl_cmd->tl_se_cmd;
 219	se_sess = tl_tpg->tl_nexus->se_sess;
 220
 221	rc = target_submit_tmr(se_cmd, se_sess, tl_cmd->tl_sense_buf, lun,
 222			       NULL, tmr, GFP_KERNEL, task,
 223			       TARGET_SCF_ACK_KREF);
 224	if (rc < 0)
 225		goto release;
 226	wait_for_completion(&tl_cmd->tmr_done);
 227	ret = se_cmd->se_tmr_req->response;
 228	target_put_sess_cmd(se_cmd);
 229
 230out:
 231	return ret;
 232
 233release:
 234	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 235	goto out;
 236}
 237
 238static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 239{
 240	struct tcm_loop_hba *tl_hba;
 241	struct tcm_loop_tpg *tl_tpg;
 242	int ret = FAILED;
 243
 244	/*
 245	 * Locate the tcm_loop_hba_t pointer
 246	 */
 247	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 248	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 249	ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 250				 sc->request->tag, TMR_ABORT_TASK);
 251	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 252}
 253
 254/*
 255 * Called from SCSI EH process context to issue a LUN_RESET TMR
 256 * to struct scsi_device
 257 */
 258static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 259{
 260	struct tcm_loop_hba *tl_hba;
 261	struct tcm_loop_tpg *tl_tpg;
 262	int ret = FAILED;
 263
 264	/*
 265	 * Locate the tcm_loop_hba_t pointer
 266	 */
 267	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 268	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 269
 270	ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 271				 0, TMR_LUN_RESET);
 272	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 273}
 274
 275static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 276{
 277	struct tcm_loop_hba *tl_hba;
 278	struct tcm_loop_tpg *tl_tpg;
 279
 280	/*
 281	 * Locate the tcm_loop_hba_t pointer
 282	 */
 283	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 284	if (!tl_hba) {
 285		pr_err("Unable to perform device reset without active I_T Nexus\n");
 286		return FAILED;
 287	}
 288	/*
 289	 * Locate the tl_tpg pointer from TargetID in sc->device->id
 290	 */
 291	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 292	if (tl_tpg) {
 293		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 294		return SUCCESS;
 295	}
 296	return FAILED;
 297}
 298
 299static struct scsi_host_template tcm_loop_driver_template = {
 300	.show_info		= tcm_loop_show_info,
 301	.proc_name		= "tcm_loopback",
 302	.name			= "TCM_Loopback",
 303	.queuecommand		= tcm_loop_queuecommand,
 304	.change_queue_depth	= scsi_change_queue_depth,
 305	.eh_abort_handler = tcm_loop_abort_task,
 306	.eh_device_reset_handler = tcm_loop_device_reset,
 307	.eh_target_reset_handler = tcm_loop_target_reset,
 308	.can_queue		= 1024,
 309	.this_id		= -1,
 310	.sg_tablesize		= 256,
 311	.cmd_per_lun		= 1024,
 312	.max_sectors		= 0xFFFF,
 313	.dma_boundary		= PAGE_SIZE - 1,
 314	.module			= THIS_MODULE,
 315	.track_queue_depth	= 1,
 
 316};
 317
 318static int tcm_loop_driver_probe(struct device *dev)
 319{
 320	struct tcm_loop_hba *tl_hba;
 321	struct Scsi_Host *sh;
 322	int error, host_prot;
 323
 324	tl_hba = to_tcm_loop_hba(dev);
 325
 326	sh = scsi_host_alloc(&tcm_loop_driver_template,
 327			sizeof(struct tcm_loop_hba));
 328	if (!sh) {
 329		pr_err("Unable to allocate struct scsi_host\n");
 330		return -ENODEV;
 331	}
 332	tl_hba->sh = sh;
 333
 334	/*
 335	 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 336	 */
 337	*((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 338	/*
 339	 * Setup single ID, Channel and LUN for now..
 340	 */
 341	sh->max_id = 2;
 342	sh->max_lun = 0;
 343	sh->max_channel = 0;
 344	sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 
 
 
 345
 346	host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 347		    SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 348		    SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 349
 350	scsi_host_set_prot(sh, host_prot);
 351	scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 352
 353	error = scsi_add_host(sh, &tl_hba->dev);
 354	if (error) {
 355		pr_err("%s: scsi_add_host failed\n", __func__);
 356		scsi_host_put(sh);
 357		return -ENODEV;
 358	}
 359	return 0;
 360}
 361
 362static int tcm_loop_driver_remove(struct device *dev)
 363{
 364	struct tcm_loop_hba *tl_hba;
 365	struct Scsi_Host *sh;
 366
 367	tl_hba = to_tcm_loop_hba(dev);
 368	sh = tl_hba->sh;
 369
 370	scsi_remove_host(sh);
 371	scsi_host_put(sh);
 372	return 0;
 373}
 374
 375static void tcm_loop_release_adapter(struct device *dev)
 376{
 377	struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 378
 379	kfree(tl_hba);
 380}
 381
 382/*
 383 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 384 */
 385static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 386{
 387	int ret;
 388
 389	tl_hba->dev.bus = &tcm_loop_lld_bus;
 390	tl_hba->dev.parent = tcm_loop_primary;
 391	tl_hba->dev.release = &tcm_loop_release_adapter;
 392	dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 393
 394	ret = device_register(&tl_hba->dev);
 395	if (ret) {
 396		pr_err("device_register() failed for tl_hba->dev: %d\n", ret);
 397		return -ENODEV;
 398	}
 399
 400	return 0;
 401}
 402
 403/*
 404 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 405 * tcm_loop SCSI bus.
 406 */
 407static int tcm_loop_alloc_core_bus(void)
 408{
 409	int ret;
 410
 411	tcm_loop_primary = root_device_register("tcm_loop_0");
 412	if (IS_ERR(tcm_loop_primary)) {
 413		pr_err("Unable to allocate tcm_loop_primary\n");
 414		return PTR_ERR(tcm_loop_primary);
 415	}
 416
 417	ret = bus_register(&tcm_loop_lld_bus);
 418	if (ret) {
 419		pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 420		goto dev_unreg;
 421	}
 422
 423	ret = driver_register(&tcm_loop_driverfs);
 424	if (ret) {
 425		pr_err("driver_register() failed for tcm_loop_driverfs\n");
 426		goto bus_unreg;
 427	}
 428
 429	pr_debug("Initialized TCM Loop Core Bus\n");
 430	return ret;
 431
 432bus_unreg:
 433	bus_unregister(&tcm_loop_lld_bus);
 434dev_unreg:
 435	root_device_unregister(tcm_loop_primary);
 436	return ret;
 437}
 438
 439static void tcm_loop_release_core_bus(void)
 440{
 441	driver_unregister(&tcm_loop_driverfs);
 442	bus_unregister(&tcm_loop_lld_bus);
 443	root_device_unregister(tcm_loop_primary);
 444
 445	pr_debug("Releasing TCM Loop Core BUS\n");
 446}
 447
 448static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
 449{
 450	return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 451}
 452
 453static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 454{
 455	/*
 456	 * Return the passed NAA identifier for the Target Port
 457	 */
 458	return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
 459}
 460
 461static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 462{
 463	/*
 464	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 465	 * to represent the SCSI Target Port.
 466	 */
 467	return tl_tpg(se_tpg)->tl_tpgt;
 468}
 469
 470/*
 471 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 472 * based upon the incoming fabric dependent SCSI Initiator Port
 473 */
 474static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 475{
 476	return 1;
 477}
 478
 479static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 480{
 481	return 0;
 482}
 483
 484/*
 485 * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 486 * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 487 */
 488static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 489{
 490	return 0;
 491}
 492
 493/*
 494 * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 495 * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 496 * It has been added here as a nop for target_fabric_tf_ops_check()
 497 */
 498static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 499{
 500	return 0;
 501}
 502
 503static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
 504{
 505	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 506						   tl_se_tpg);
 507	return tl_tpg->tl_fabric_prot_type;
 508}
 509
 510static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 511{
 512	return 1;
 513}
 514
 515static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 516{
 517	return 1;
 518}
 519
 520static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 521{
 522	return;
 523}
 524
 525static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 526{
 527	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 528			struct tcm_loop_cmd, tl_se_cmd);
 529
 530	return tl_cmd->sc_cmd_state;
 531}
 532
 533static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 534{
 535	/*
 536	 * Since Linux/SCSI has already sent down a struct scsi_cmnd
 537	 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 538	 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 539	 * format with transport_generic_map_mem_to_cmd().
 540	 *
 541	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
 542	 * object execution queue.
 543	 */
 544	target_execute_cmd(se_cmd);
 545	return 0;
 546}
 547
 548static int tcm_loop_queue_data_or_status(const char *func,
 549		struct se_cmd *se_cmd, u8 scsi_status)
 550{
 551	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 552				struct tcm_loop_cmd, tl_se_cmd);
 553	struct scsi_cmnd *sc = tl_cmd->sc;
 554
 555	pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
 556		 func, sc, sc->cmnd[0]);
 557
 558	if (se_cmd->sense_buffer &&
 559	   ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 560	    (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 561
 562		memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 563				SCSI_SENSE_BUFFERSIZE);
 564		sc->result = SAM_STAT_CHECK_CONDITION;
 565		set_driver_byte(sc, DRIVER_SENSE);
 566	} else
 567		sc->result = scsi_status;
 568
 569	set_host_byte(sc, DID_OK);
 570	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 571	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 572		scsi_set_resid(sc, se_cmd->residual_count);
 573	sc->scsi_done(sc);
 574	return 0;
 575}
 576
 577static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 578{
 579	return tcm_loop_queue_data_or_status(__func__, se_cmd, SAM_STAT_GOOD);
 580}
 581
 582static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 583{
 584	return tcm_loop_queue_data_or_status(__func__,
 585					     se_cmd, se_cmd->scsi_status);
 586}
 587
 588static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 589{
 590	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 591				struct tcm_loop_cmd, tl_se_cmd);
 592
 593	/* Wake up tcm_loop_issue_tmr(). */
 594	complete(&tl_cmd->tmr_done);
 595}
 596
 597static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 598{
 599	return;
 600}
 601
 602static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 603{
 604	switch (tl_hba->tl_proto_id) {
 605	case SCSI_PROTOCOL_SAS:
 606		return "SAS";
 607	case SCSI_PROTOCOL_FCP:
 608		return "FCP";
 609	case SCSI_PROTOCOL_ISCSI:
 610		return "iSCSI";
 611	default:
 612		break;
 613	}
 614
 615	return "Unknown";
 616}
 617
 618/* Start items for tcm_loop_port_cit */
 619
 620static int tcm_loop_port_link(
 621	struct se_portal_group *se_tpg,
 622	struct se_lun *lun)
 623{
 624	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 625				struct tcm_loop_tpg, tl_se_tpg);
 626	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 627
 628	atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 629	/*
 630	 * Add Linux/SCSI struct scsi_device by HCTL
 631	 */
 632	scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 633
 634	pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 635	return 0;
 636}
 637
 638static void tcm_loop_port_unlink(
 639	struct se_portal_group *se_tpg,
 640	struct se_lun *se_lun)
 641{
 642	struct scsi_device *sd;
 643	struct tcm_loop_hba *tl_hba;
 644	struct tcm_loop_tpg *tl_tpg;
 645
 646	tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 647	tl_hba = tl_tpg->tl_hba;
 648
 649	sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 650				se_lun->unpacked_lun);
 651	if (!sd) {
 652		pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n",
 653		       0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 654		return;
 655	}
 656	/*
 657	 * Remove Linux/SCSI struct scsi_device by HCTL
 658	 */
 659	scsi_remove_device(sd);
 660	scsi_device_put(sd);
 661
 662	atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 663
 664	pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 665}
 666
 667/* End items for tcm_loop_port_cit */
 668
 669static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
 670		struct config_item *item, char *page)
 671{
 672	struct se_portal_group *se_tpg = attrib_to_tpg(item);
 673	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 674						   tl_se_tpg);
 675
 676	return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
 677}
 678
 679static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
 680		struct config_item *item, const char *page, size_t count)
 681{
 682	struct se_portal_group *se_tpg = attrib_to_tpg(item);
 683	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 684						   tl_se_tpg);
 685	unsigned long val;
 686	int ret = kstrtoul(page, 0, &val);
 687
 688	if (ret) {
 689		pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
 690		return ret;
 691	}
 692	if (val != 0 && val != 1 && val != 3) {
 693		pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
 694		return -EINVAL;
 695	}
 696	tl_tpg->tl_fabric_prot_type = val;
 697
 698	return count;
 699}
 700
 701CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
 702
 703static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
 704	&tcm_loop_tpg_attrib_attr_fabric_prot_type,
 705	NULL,
 706};
 707
 708/* Start items for tcm_loop_nexus_cit */
 709
 710static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
 711				  struct se_session *se_sess, void *p)
 712{
 713	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 714					struct tcm_loop_tpg, tl_se_tpg);
 715
 716	tl_tpg->tl_nexus = p;
 717	return 0;
 718}
 719
 720static int tcm_loop_make_nexus(
 721	struct tcm_loop_tpg *tl_tpg,
 722	const char *name)
 723{
 724	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 725	struct tcm_loop_nexus *tl_nexus;
 726	int ret;
 727
 728	if (tl_tpg->tl_nexus) {
 729		pr_debug("tl_tpg->tl_nexus already exists\n");
 730		return -EEXIST;
 731	}
 732
 733	tl_nexus = kzalloc(sizeof(*tl_nexus), GFP_KERNEL);
 734	if (!tl_nexus)
 735		return -ENOMEM;
 736
 737	tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0,
 738					TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
 739					name, tl_nexus, tcm_loop_alloc_sess_cb);
 740	if (IS_ERR(tl_nexus->se_sess)) {
 741		ret = PTR_ERR(tl_nexus->se_sess);
 742		kfree(tl_nexus);
 743		return ret;
 744	}
 745
 746	pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n",
 747		 tcm_loop_dump_proto_id(tl_hba), name);
 748	return 0;
 749}
 750
 751static int tcm_loop_drop_nexus(
 752	struct tcm_loop_tpg *tpg)
 753{
 754	struct se_session *se_sess;
 755	struct tcm_loop_nexus *tl_nexus;
 756
 757	tl_nexus = tpg->tl_nexus;
 758	if (!tl_nexus)
 759		return -ENODEV;
 760
 761	se_sess = tl_nexus->se_sess;
 762	if (!se_sess)
 763		return -ENODEV;
 764
 765	if (atomic_read(&tpg->tl_tpg_port_count)) {
 766		pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n",
 767		       atomic_read(&tpg->tl_tpg_port_count));
 768		return -EPERM;
 769	}
 770
 771	pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
 772		 tcm_loop_dump_proto_id(tpg->tl_hba),
 773		 tl_nexus->se_sess->se_node_acl->initiatorname);
 774	/*
 775	 * Release the SCSI I_T Nexus to the emulated Target Port
 776	 */
 777	target_remove_session(se_sess);
 778	tpg->tl_nexus = NULL;
 779	kfree(tl_nexus);
 780	return 0;
 781}
 782
 783/* End items for tcm_loop_nexus_cit */
 784
 785static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
 786{
 787	struct se_portal_group *se_tpg = to_tpg(item);
 788	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 789			struct tcm_loop_tpg, tl_se_tpg);
 790	struct tcm_loop_nexus *tl_nexus;
 791	ssize_t ret;
 792
 793	tl_nexus = tl_tpg->tl_nexus;
 794	if (!tl_nexus)
 795		return -ENODEV;
 796
 797	ret = snprintf(page, PAGE_SIZE, "%s\n",
 798		tl_nexus->se_sess->se_node_acl->initiatorname);
 799
 800	return ret;
 801}
 802
 803static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
 804		const char *page, size_t count)
 805{
 806	struct se_portal_group *se_tpg = to_tpg(item);
 807	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 808			struct tcm_loop_tpg, tl_se_tpg);
 809	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 810	unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
 811	int ret;
 812	/*
 813	 * Shutdown the active I_T nexus if 'NULL' is passed..
 814	 */
 815	if (!strncmp(page, "NULL", 4)) {
 816		ret = tcm_loop_drop_nexus(tl_tpg);
 817		return (!ret) ? count : ret;
 818	}
 819	/*
 820	 * Otherwise make sure the passed virtual Initiator port WWN matches
 821	 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
 822	 * tcm_loop_make_nexus()
 823	 */
 824	if (strlen(page) >= TL_WWN_ADDR_LEN) {
 825		pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
 826		       page, TL_WWN_ADDR_LEN);
 827		return -EINVAL;
 828	}
 829	snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
 830
 831	ptr = strstr(i_port, "naa.");
 832	if (ptr) {
 833		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
 834			pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
 835			       i_port, tcm_loop_dump_proto_id(tl_hba));
 836			return -EINVAL;
 837		}
 838		port_ptr = &i_port[0];
 839		goto check_newline;
 840	}
 841	ptr = strstr(i_port, "fc.");
 842	if (ptr) {
 843		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
 844			pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
 845			       i_port, tcm_loop_dump_proto_id(tl_hba));
 846			return -EINVAL;
 847		}
 848		port_ptr = &i_port[3]; /* Skip over "fc." */
 849		goto check_newline;
 850	}
 851	ptr = strstr(i_port, "iqn.");
 852	if (ptr) {
 853		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
 854			pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
 855			       i_port, tcm_loop_dump_proto_id(tl_hba));
 856			return -EINVAL;
 857		}
 858		port_ptr = &i_port[0];
 859		goto check_newline;
 860	}
 861	pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
 862	       i_port);
 863	return -EINVAL;
 864	/*
 865	 * Clear any trailing newline for the NAA WWN
 866	 */
 867check_newline:
 868	if (i_port[strlen(i_port)-1] == '\n')
 869		i_port[strlen(i_port)-1] = '\0';
 870
 871	ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
 872	if (ret < 0)
 873		return ret;
 874
 875	return count;
 876}
 877
 878static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
 879		char *page)
 880{
 881	struct se_portal_group *se_tpg = to_tpg(item);
 882	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 883			struct tcm_loop_tpg, tl_se_tpg);
 884	const char *status = NULL;
 885	ssize_t ret = -EINVAL;
 886
 887	switch (tl_tpg->tl_transport_status) {
 888	case TCM_TRANSPORT_ONLINE:
 889		status = "online";
 890		break;
 891	case TCM_TRANSPORT_OFFLINE:
 892		status = "offline";
 893		break;
 894	default:
 895		break;
 896	}
 897
 898	if (status)
 899		ret = snprintf(page, PAGE_SIZE, "%s\n", status);
 900
 901	return ret;
 902}
 903
 904static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
 905		const char *page, size_t count)
 906{
 907	struct se_portal_group *se_tpg = to_tpg(item);
 908	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 909			struct tcm_loop_tpg, tl_se_tpg);
 910
 911	if (!strncmp(page, "online", 6)) {
 912		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 913		return count;
 914	}
 915	if (!strncmp(page, "offline", 7)) {
 916		tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
 917		if (tl_tpg->tl_nexus) {
 918			struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
 919
 920			core_allocate_nexus_loss_ua(tl_sess->se_node_acl);
 921		}
 922		return count;
 923	}
 924	return -EINVAL;
 925}
 926
 927static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
 928					 char *page)
 929{
 930	struct se_portal_group *se_tpg = to_tpg(item);
 931	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 932			struct tcm_loop_tpg, tl_se_tpg);
 933	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 934
 935	return snprintf(page, PAGE_SIZE, "%d:0:%d\n",
 936			tl_hba->sh->host_no, tl_tpg->tl_tpgt);
 937}
 938
 939CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
 940CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
 941CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
 942
 943static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
 944	&tcm_loop_tpg_attr_nexus,
 945	&tcm_loop_tpg_attr_transport_status,
 946	&tcm_loop_tpg_attr_address,
 947	NULL,
 948};
 949
 950/* Start items for tcm_loop_naa_cit */
 951
 952static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn,
 953						     const char *name)
 954{
 955	struct tcm_loop_hba *tl_hba = container_of(wwn,
 956			struct tcm_loop_hba, tl_hba_wwn);
 957	struct tcm_loop_tpg *tl_tpg;
 958	int ret;
 959	unsigned long tpgt;
 960
 961	if (strstr(name, "tpgt_") != name) {
 962		pr_err("Unable to locate \"tpgt_#\" directory group\n");
 963		return ERR_PTR(-EINVAL);
 964	}
 965	if (kstrtoul(name+5, 10, &tpgt))
 966		return ERR_PTR(-EINVAL);
 967
 968	if (tpgt >= TL_TPGS_PER_HBA) {
 969		pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
 970		       tpgt, TL_TPGS_PER_HBA);
 971		return ERR_PTR(-EINVAL);
 972	}
 973	tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
 974	tl_tpg->tl_hba = tl_hba;
 975	tl_tpg->tl_tpgt = tpgt;
 976	/*
 977	 * Register the tl_tpg as a emulated TCM Target Endpoint
 978	 */
 979	ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
 980	if (ret < 0)
 981		return ERR_PTR(-ENOMEM);
 982
 983	pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
 984		 tcm_loop_dump_proto_id(tl_hba),
 985		 config_item_name(&wwn->wwn_group.cg_item), tpgt);
 986	return &tl_tpg->tl_se_tpg;
 987}
 988
 989static void tcm_loop_drop_naa_tpg(
 990	struct se_portal_group *se_tpg)
 991{
 992	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
 993	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 994				struct tcm_loop_tpg, tl_se_tpg);
 995	struct tcm_loop_hba *tl_hba;
 996	unsigned short tpgt;
 997
 998	tl_hba = tl_tpg->tl_hba;
 999	tpgt = tl_tpg->tl_tpgt;
1000	/*
1001	 * Release the I_T Nexus for the Virtual target link if present
1002	 */
1003	tcm_loop_drop_nexus(tl_tpg);
1004	/*
1005	 * Deregister the tl_tpg as a emulated TCM Target Endpoint
1006	 */
1007	core_tpg_deregister(se_tpg);
1008
1009	tl_tpg->tl_hba = NULL;
1010	tl_tpg->tl_tpgt = 0;
1011
1012	pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
1013		 tcm_loop_dump_proto_id(tl_hba),
1014		 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1015}
1016
1017/* End items for tcm_loop_naa_cit */
1018
1019/* Start items for tcm_loop_cit */
1020
1021static struct se_wwn *tcm_loop_make_scsi_hba(
1022	struct target_fabric_configfs *tf,
1023	struct config_group *group,
1024	const char *name)
1025{
1026	struct tcm_loop_hba *tl_hba;
1027	struct Scsi_Host *sh;
1028	char *ptr;
1029	int ret, off = 0;
1030
1031	tl_hba = kzalloc(sizeof(*tl_hba), GFP_KERNEL);
1032	if (!tl_hba)
1033		return ERR_PTR(-ENOMEM);
1034
1035	/*
1036	 * Determine the emulated Protocol Identifier and Target Port Name
1037	 * based on the incoming configfs directory name.
1038	 */
1039	ptr = strstr(name, "naa.");
1040	if (ptr) {
1041		tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1042		goto check_len;
1043	}
1044	ptr = strstr(name, "fc.");
1045	if (ptr) {
1046		tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1047		off = 3; /* Skip over "fc." */
1048		goto check_len;
1049	}
1050	ptr = strstr(name, "iqn.");
1051	if (!ptr) {
1052		pr_err("Unable to locate prefix for emulated Target Port: %s\n",
1053		       name);
1054		ret = -EINVAL;
1055		goto out;
1056	}
1057	tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1058
1059check_len:
1060	if (strlen(name) >= TL_WWN_ADDR_LEN) {
1061		pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
1062		       name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN);
1063		ret = -EINVAL;
1064		goto out;
1065	}
1066	snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1067
1068	/*
1069	 * Call device_register(tl_hba->dev) to register the emulated
1070	 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1071	 * device_register() callbacks in tcm_loop_driver_probe()
1072	 */
1073	ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1074	if (ret)
1075		goto out;
1076
1077	sh = tl_hba->sh;
1078	tcm_loop_hba_no_cnt++;
1079	pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1080		 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1081	return &tl_hba->tl_hba_wwn;
1082out:
1083	kfree(tl_hba);
1084	return ERR_PTR(ret);
1085}
1086
1087static void tcm_loop_drop_scsi_hba(
1088	struct se_wwn *wwn)
1089{
1090	struct tcm_loop_hba *tl_hba = container_of(wwn,
1091				struct tcm_loop_hba, tl_hba_wwn);
1092
1093	pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1094		 tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1095		 tl_hba->sh->host_no);
1096	/*
1097	 * Call device_unregister() on the original tl_hba->dev.
1098	 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1099	 * release *tl_hba;
1100	 */
1101	device_unregister(&tl_hba->dev);
1102}
1103
1104/* Start items for tcm_loop_cit */
1105static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1106{
1107	return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1108}
1109
1110CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1111
1112static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1113	&tcm_loop_wwn_attr_version,
1114	NULL,
1115};
1116
1117/* End items for tcm_loop_cit */
1118
1119static const struct target_core_fabric_ops loop_ops = {
1120	.module				= THIS_MODULE,
1121	.fabric_name			= "loopback",
1122	.tpg_get_wwn			= tcm_loop_get_endpoint_wwn,
1123	.tpg_get_tag			= tcm_loop_get_tag,
1124	.tpg_check_demo_mode		= tcm_loop_check_demo_mode,
1125	.tpg_check_demo_mode_cache	= tcm_loop_check_demo_mode_cache,
1126	.tpg_check_demo_mode_write_protect =
1127				tcm_loop_check_demo_mode_write_protect,
1128	.tpg_check_prod_mode_write_protect =
1129				tcm_loop_check_prod_mode_write_protect,
1130	.tpg_check_prot_fabric_only	= tcm_loop_check_prot_fabric_only,
1131	.tpg_get_inst_index		= tcm_loop_get_inst_index,
1132	.check_stop_free		= tcm_loop_check_stop_free,
1133	.release_cmd			= tcm_loop_release_cmd,
1134	.sess_get_index			= tcm_loop_sess_get_index,
1135	.write_pending			= tcm_loop_write_pending,
1136	.set_default_node_attributes	= tcm_loop_set_default_node_attributes,
1137	.get_cmd_state			= tcm_loop_get_cmd_state,
1138	.queue_data_in			= tcm_loop_queue_data_in,
1139	.queue_status			= tcm_loop_queue_status,
1140	.queue_tm_rsp			= tcm_loop_queue_tm_rsp,
1141	.aborted_task			= tcm_loop_aborted_task,
1142	.fabric_make_wwn		= tcm_loop_make_scsi_hba,
1143	.fabric_drop_wwn		= tcm_loop_drop_scsi_hba,
1144	.fabric_make_tpg		= tcm_loop_make_naa_tpg,
1145	.fabric_drop_tpg		= tcm_loop_drop_naa_tpg,
1146	.fabric_post_link		= tcm_loop_port_link,
1147	.fabric_pre_unlink		= tcm_loop_port_unlink,
1148	.tfc_wwn_attrs			= tcm_loop_wwn_attrs,
1149	.tfc_tpg_base_attrs		= tcm_loop_tpg_attrs,
1150	.tfc_tpg_attrib_attrs		= tcm_loop_tpg_attrib_attrs,
1151};
1152
1153static int __init tcm_loop_fabric_init(void)
1154{
1155	int ret = -ENOMEM;
1156
1157	tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1158	if (!tcm_loop_workqueue)
1159		goto out;
1160
1161	tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1162				sizeof(struct tcm_loop_cmd),
1163				__alignof__(struct tcm_loop_cmd),
1164				0, NULL);
1165	if (!tcm_loop_cmd_cache) {
1166		pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n");
1167		goto out_destroy_workqueue;
1168	}
1169
1170	ret = tcm_loop_alloc_core_bus();
1171	if (ret)
1172		goto out_destroy_cache;
1173
1174	ret = target_register_template(&loop_ops);
1175	if (ret)
1176		goto out_release_core_bus;
1177
1178	return 0;
1179
1180out_release_core_bus:
1181	tcm_loop_release_core_bus();
1182out_destroy_cache:
1183	kmem_cache_destroy(tcm_loop_cmd_cache);
1184out_destroy_workqueue:
1185	destroy_workqueue(tcm_loop_workqueue);
1186out:
1187	return ret;
1188}
1189
1190static void __exit tcm_loop_fabric_exit(void)
1191{
1192	target_unregister_template(&loop_ops);
1193	tcm_loop_release_core_bus();
1194	kmem_cache_destroy(tcm_loop_cmd_cache);
1195	destroy_workqueue(tcm_loop_workqueue);
1196}
1197
1198MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1199MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1200MODULE_LICENSE("GPL");
1201module_init(tcm_loop_fabric_init);
1202module_exit(tcm_loop_fabric_exit);
v5.14.15
   1/*******************************************************************************
   2 *
   3 * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4 * for emulated SAS initiator ports
   5 *
   6 * © Copyright 2011-2013 Datera, Inc.
   7 *
   8 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9 *
  10 * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 ****************************************************************************/
  22
  23#include <linux/module.h>
  24#include <linux/moduleparam.h>
  25#include <linux/init.h>
  26#include <linux/slab.h>
  27#include <linux/types.h>
  28#include <linux/configfs.h>
  29#include <scsi/scsi.h>
  30#include <scsi/scsi_tcq.h>
  31#include <scsi/scsi_host.h>
  32#include <scsi/scsi_device.h>
  33#include <scsi/scsi_cmnd.h>
  34
  35#include <target/target_core_base.h>
  36#include <target/target_core_fabric.h>
  37
  38#include "tcm_loop.h"
  39
  40#define to_tcm_loop_hba(hba)	container_of(hba, struct tcm_loop_hba, dev)
  41
 
  42static struct kmem_cache *tcm_loop_cmd_cache;
  43
  44static int tcm_loop_hba_no_cnt;
  45
  46static int tcm_loop_queue_status(struct se_cmd *se_cmd);
  47
  48static unsigned int tcm_loop_nr_hw_queues = 1;
  49module_param_named(nr_hw_queues, tcm_loop_nr_hw_queues, uint, 0644);
  50
  51static unsigned int tcm_loop_can_queue = 1024;
  52module_param_named(can_queue, tcm_loop_can_queue, uint, 0644);
  53
  54static unsigned int tcm_loop_cmd_per_lun = 1024;
  55module_param_named(cmd_per_lun, tcm_loop_cmd_per_lun, uint, 0644);
  56
  57/*
  58 * Called from struct target_core_fabric_ops->check_stop_free()
  59 */
  60static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  61{
  62	return transport_generic_free_cmd(se_cmd, 0);
  63}
  64
  65static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  66{
  67	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  68				struct tcm_loop_cmd, tl_se_cmd);
  69	struct scsi_cmnd *sc = tl_cmd->sc;
  70
  71	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
  72		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  73	else
  74		sc->scsi_done(sc);
  75}
  76
  77static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
  78{
  79	seq_puts(m, "tcm_loop_proc_info()\n");
  80	return 0;
  81}
  82
  83static int tcm_loop_driver_probe(struct device *);
  84static int tcm_loop_driver_remove(struct device *);
  85
  86static int pseudo_lld_bus_match(struct device *dev,
  87				struct device_driver *dev_driver)
  88{
  89	return 1;
  90}
  91
  92static struct bus_type tcm_loop_lld_bus = {
  93	.name			= "tcm_loop_bus",
  94	.match			= pseudo_lld_bus_match,
  95	.probe			= tcm_loop_driver_probe,
  96	.remove			= tcm_loop_driver_remove,
  97};
  98
  99static struct device_driver tcm_loop_driverfs = {
 100	.name			= "tcm_loop",
 101	.bus			= &tcm_loop_lld_bus,
 102};
 103/*
 104 * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 105 */
 106static struct device *tcm_loop_primary;
 107
 108static void tcm_loop_target_queue_cmd(struct tcm_loop_cmd *tl_cmd)
 109{
 
 
 110	struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 111	struct scsi_cmnd *sc = tl_cmd->sc;
 112	struct tcm_loop_nexus *tl_nexus;
 113	struct tcm_loop_hba *tl_hba;
 114	struct tcm_loop_tpg *tl_tpg;
 115	struct scatterlist *sgl_bidi = NULL;
 116	u32 sgl_bidi_count = 0, transfer_length;
 
 117
 118	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 119	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 120
 121	/*
 122	 * Ensure that this tl_tpg reference from the incoming sc->device->id
 123	 * has already been configured via tcm_loop_make_naa_tpg().
 124	 */
 125	if (!tl_tpg->tl_hba) {
 126		set_host_byte(sc, DID_NO_CONNECT);
 127		goto out_done;
 128	}
 129	if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
 130		set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
 131		goto out_done;
 132	}
 133	tl_nexus = tl_tpg->tl_nexus;
 134	if (!tl_nexus) {
 135		scmd_printk(KERN_ERR, sc,
 136			    "TCM_Loop I_T Nexus does not exist\n");
 137		set_host_byte(sc, DID_ERROR);
 138		goto out_done;
 139	}
 140
 141	transfer_length = scsi_transfer_length(sc);
 142	if (!scsi_prot_sg_count(sc) &&
 143	    scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
 144		se_cmd->prot_pto = true;
 145		/*
 146		 * loopback transport doesn't support
 147		 * WRITE_GENERATE, READ_STRIP protection
 148		 * information operations, go ahead unprotected.
 149		 */
 150		transfer_length = scsi_bufflen(sc);
 151	}
 152
 153	se_cmd->tag = tl_cmd->sc_cmd_tag;
 154	target_init_cmd(se_cmd, tl_nexus->se_sess, &tl_cmd->tl_sense_buf[0],
 155			tl_cmd->sc->device->lun, transfer_length,
 156			TCM_SIMPLE_TAG, sc->sc_data_direction, 0);
 157
 158	if (target_submit_prep(se_cmd, sc->cmnd, scsi_sglist(sc),
 159			       scsi_sg_count(sc), sgl_bidi, sgl_bidi_count,
 160			       scsi_prot_sglist(sc), scsi_prot_sg_count(sc),
 161			       GFP_ATOMIC))
 162		return;
 163
 164	target_queue_submission(se_cmd);
 165	return;
 166
 167out_done:
 
 168	sc->scsi_done(sc);
 169}
 170
 171/*
 172 * ->queuecommand can be and usually is called from interrupt context, so
 173 * defer the actual submission to a workqueue.
 174 */
 175static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 176{
 177	struct tcm_loop_cmd *tl_cmd = scsi_cmd_priv(sc);
 178
 179	pr_debug("%s() %d:%d:%d:%llu got CDB: 0x%02x scsi_buf_len: %u\n",
 180		 __func__, sc->device->host->host_no, sc->device->id,
 181		 sc->device->channel, sc->device->lun, sc->cmnd[0],
 182		 scsi_bufflen(sc));
 183
 184	memset(tl_cmd, 0, sizeof(*tl_cmd));
 
 
 
 
 
 
 185	tl_cmd->sc = sc;
 186	tl_cmd->sc_cmd_tag = sc->request->tag;
 187
 188	tcm_loop_target_queue_cmd(tl_cmd);
 189	return 0;
 190}
 191
 192/*
 193 * Called from SCSI EH process context to issue a LUN_RESET TMR
 194 * to struct scsi_device
 195 */
 196static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
 197			      u64 lun, int task, enum tcm_tmreq_table tmr)
 198{
 199	struct se_cmd *se_cmd;
 200	struct se_session *se_sess;
 201	struct tcm_loop_nexus *tl_nexus;
 202	struct tcm_loop_cmd *tl_cmd;
 203	int ret = TMR_FUNCTION_FAILED, rc;
 204
 205	/*
 206	 * Locate the tl_nexus and se_sess pointers
 207	 */
 208	tl_nexus = tl_tpg->tl_nexus;
 209	if (!tl_nexus) {
 210		pr_err("Unable to perform device reset without active I_T Nexus\n");
 211		return ret;
 212	}
 213
 214	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 215	if (!tl_cmd)
 216		return ret;
 217
 218	init_completion(&tl_cmd->tmr_done);
 219
 220	se_cmd = &tl_cmd->tl_se_cmd;
 221	se_sess = tl_tpg->tl_nexus->se_sess;
 222
 223	rc = target_submit_tmr(se_cmd, se_sess, tl_cmd->tl_sense_buf, lun,
 224			       NULL, tmr, GFP_KERNEL, task,
 225			       TARGET_SCF_ACK_KREF);
 226	if (rc < 0)
 227		goto release;
 228	wait_for_completion(&tl_cmd->tmr_done);
 229	ret = se_cmd->se_tmr_req->response;
 230	target_put_sess_cmd(se_cmd);
 231
 232out:
 233	return ret;
 234
 235release:
 236	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 237	goto out;
 238}
 239
 240static int tcm_loop_abort_task(struct scsi_cmnd *sc)
 241{
 242	struct tcm_loop_hba *tl_hba;
 243	struct tcm_loop_tpg *tl_tpg;
 244	int ret = FAILED;
 245
 246	/*
 247	 * Locate the tcm_loop_hba_t pointer
 248	 */
 249	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 250	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 251	ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 252				 sc->request->tag, TMR_ABORT_TASK);
 253	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 254}
 255
 256/*
 257 * Called from SCSI EH process context to issue a LUN_RESET TMR
 258 * to struct scsi_device
 259 */
 260static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 261{
 262	struct tcm_loop_hba *tl_hba;
 263	struct tcm_loop_tpg *tl_tpg;
 264	int ret = FAILED;
 265
 266	/*
 267	 * Locate the tcm_loop_hba_t pointer
 268	 */
 269	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 270	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 271
 272	ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
 273				 0, TMR_LUN_RESET);
 274	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
 275}
 276
 277static int tcm_loop_target_reset(struct scsi_cmnd *sc)
 278{
 279	struct tcm_loop_hba *tl_hba;
 280	struct tcm_loop_tpg *tl_tpg;
 281
 282	/*
 283	 * Locate the tcm_loop_hba_t pointer
 284	 */
 285	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 286	if (!tl_hba) {
 287		pr_err("Unable to perform device reset without active I_T Nexus\n");
 288		return FAILED;
 289	}
 290	/*
 291	 * Locate the tl_tpg pointer from TargetID in sc->device->id
 292	 */
 293	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 294	if (tl_tpg) {
 295		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 296		return SUCCESS;
 297	}
 298	return FAILED;
 299}
 300
 301static struct scsi_host_template tcm_loop_driver_template = {
 302	.show_info		= tcm_loop_show_info,
 303	.proc_name		= "tcm_loopback",
 304	.name			= "TCM_Loopback",
 305	.queuecommand		= tcm_loop_queuecommand,
 306	.change_queue_depth	= scsi_change_queue_depth,
 307	.eh_abort_handler = tcm_loop_abort_task,
 308	.eh_device_reset_handler = tcm_loop_device_reset,
 309	.eh_target_reset_handler = tcm_loop_target_reset,
 
 310	.this_id		= -1,
 311	.sg_tablesize		= 256,
 
 312	.max_sectors		= 0xFFFF,
 313	.dma_boundary		= PAGE_SIZE - 1,
 314	.module			= THIS_MODULE,
 315	.track_queue_depth	= 1,
 316	.cmd_size		= sizeof(struct tcm_loop_cmd),
 317};
 318
 319static int tcm_loop_driver_probe(struct device *dev)
 320{
 321	struct tcm_loop_hba *tl_hba;
 322	struct Scsi_Host *sh;
 323	int error, host_prot;
 324
 325	tl_hba = to_tcm_loop_hba(dev);
 326
 327	sh = scsi_host_alloc(&tcm_loop_driver_template,
 328			sizeof(struct tcm_loop_hba));
 329	if (!sh) {
 330		pr_err("Unable to allocate struct scsi_host\n");
 331		return -ENODEV;
 332	}
 333	tl_hba->sh = sh;
 334
 335	/*
 336	 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 337	 */
 338	*((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 339	/*
 340	 * Setup single ID, Channel and LUN for now..
 341	 */
 342	sh->max_id = 2;
 343	sh->max_lun = 0;
 344	sh->max_channel = 0;
 345	sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
 346	sh->nr_hw_queues = tcm_loop_nr_hw_queues;
 347	sh->can_queue = tcm_loop_can_queue;
 348	sh->cmd_per_lun = tcm_loop_cmd_per_lun;
 349
 350	host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
 351		    SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
 352		    SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
 353
 354	scsi_host_set_prot(sh, host_prot);
 355	scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
 356
 357	error = scsi_add_host(sh, &tl_hba->dev);
 358	if (error) {
 359		pr_err("%s: scsi_add_host failed\n", __func__);
 360		scsi_host_put(sh);
 361		return -ENODEV;
 362	}
 363	return 0;
 364}
 365
 366static int tcm_loop_driver_remove(struct device *dev)
 367{
 368	struct tcm_loop_hba *tl_hba;
 369	struct Scsi_Host *sh;
 370
 371	tl_hba = to_tcm_loop_hba(dev);
 372	sh = tl_hba->sh;
 373
 374	scsi_remove_host(sh);
 375	scsi_host_put(sh);
 376	return 0;
 377}
 378
 379static void tcm_loop_release_adapter(struct device *dev)
 380{
 381	struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 382
 383	kfree(tl_hba);
 384}
 385
 386/*
 387 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 388 */
 389static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 390{
 391	int ret;
 392
 393	tl_hba->dev.bus = &tcm_loop_lld_bus;
 394	tl_hba->dev.parent = tcm_loop_primary;
 395	tl_hba->dev.release = &tcm_loop_release_adapter;
 396	dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 397
 398	ret = device_register(&tl_hba->dev);
 399	if (ret) {
 400		pr_err("device_register() failed for tl_hba->dev: %d\n", ret);
 401		return -ENODEV;
 402	}
 403
 404	return 0;
 405}
 406
 407/*
 408 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 409 * tcm_loop SCSI bus.
 410 */
 411static int tcm_loop_alloc_core_bus(void)
 412{
 413	int ret;
 414
 415	tcm_loop_primary = root_device_register("tcm_loop_0");
 416	if (IS_ERR(tcm_loop_primary)) {
 417		pr_err("Unable to allocate tcm_loop_primary\n");
 418		return PTR_ERR(tcm_loop_primary);
 419	}
 420
 421	ret = bus_register(&tcm_loop_lld_bus);
 422	if (ret) {
 423		pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 424		goto dev_unreg;
 425	}
 426
 427	ret = driver_register(&tcm_loop_driverfs);
 428	if (ret) {
 429		pr_err("driver_register() failed for tcm_loop_driverfs\n");
 430		goto bus_unreg;
 431	}
 432
 433	pr_debug("Initialized TCM Loop Core Bus\n");
 434	return ret;
 435
 436bus_unreg:
 437	bus_unregister(&tcm_loop_lld_bus);
 438dev_unreg:
 439	root_device_unregister(tcm_loop_primary);
 440	return ret;
 441}
 442
 443static void tcm_loop_release_core_bus(void)
 444{
 445	driver_unregister(&tcm_loop_driverfs);
 446	bus_unregister(&tcm_loop_lld_bus);
 447	root_device_unregister(tcm_loop_primary);
 448
 449	pr_debug("Releasing TCM Loop Core BUS\n");
 450}
 451
 452static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
 453{
 454	return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 455}
 456
 457static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 458{
 459	/*
 460	 * Return the passed NAA identifier for the Target Port
 461	 */
 462	return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
 463}
 464
 465static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 466{
 467	/*
 468	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 469	 * to represent the SCSI Target Port.
 470	 */
 471	return tl_tpg(se_tpg)->tl_tpgt;
 472}
 473
 474/*
 475 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 476 * based upon the incoming fabric dependent SCSI Initiator Port
 477 */
 478static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 479{
 480	return 1;
 481}
 482
 483static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 484{
 485	return 0;
 486}
 487
 488/*
 489 * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 490 * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 491 */
 492static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 493{
 494	return 0;
 495}
 496
 497/*
 498 * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 499 * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 500 * It has been added here as a nop for target_fabric_tf_ops_check()
 501 */
 502static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 503{
 504	return 0;
 505}
 506
 507static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
 508{
 509	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 510						   tl_se_tpg);
 511	return tl_tpg->tl_fabric_prot_type;
 512}
 513
 514static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 515{
 516	return 1;
 517}
 518
 519static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 520{
 521	return 1;
 522}
 523
 524static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 525{
 526	return;
 527}
 528
 529static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 530{
 531	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 532			struct tcm_loop_cmd, tl_se_cmd);
 533
 534	return tl_cmd->sc_cmd_state;
 535}
 536
 537static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 538{
 539	/*
 540	 * Since Linux/SCSI has already sent down a struct scsi_cmnd
 541	 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 542	 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 543	 * format with transport_generic_map_mem_to_cmd().
 544	 *
 545	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
 546	 * object execution queue.
 547	 */
 548	target_execute_cmd(se_cmd);
 549	return 0;
 550}
 551
 552static int tcm_loop_queue_data_or_status(const char *func,
 553		struct se_cmd *se_cmd, u8 scsi_status)
 554{
 555	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 556				struct tcm_loop_cmd, tl_se_cmd);
 557	struct scsi_cmnd *sc = tl_cmd->sc;
 558
 559	pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
 560		 func, sc, sc->cmnd[0]);
 561
 562	if (se_cmd->sense_buffer &&
 563	   ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 564	    (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 565
 566		memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 567				SCSI_SENSE_BUFFERSIZE);
 568		sc->result = SAM_STAT_CHECK_CONDITION;
 
 569	} else
 570		sc->result = scsi_status;
 571
 572	set_host_byte(sc, DID_OK);
 573	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 574	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 575		scsi_set_resid(sc, se_cmd->residual_count);
 
 576	return 0;
 577}
 578
 579static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 580{
 581	return tcm_loop_queue_data_or_status(__func__, se_cmd, SAM_STAT_GOOD);
 582}
 583
 584static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 585{
 586	return tcm_loop_queue_data_or_status(__func__,
 587					     se_cmd, se_cmd->scsi_status);
 588}
 589
 590static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 591{
 592	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 593				struct tcm_loop_cmd, tl_se_cmd);
 594
 595	/* Wake up tcm_loop_issue_tmr(). */
 596	complete(&tl_cmd->tmr_done);
 597}
 598
 599static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
 600{
 601	return;
 602}
 603
 604static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 605{
 606	switch (tl_hba->tl_proto_id) {
 607	case SCSI_PROTOCOL_SAS:
 608		return "SAS";
 609	case SCSI_PROTOCOL_FCP:
 610		return "FCP";
 611	case SCSI_PROTOCOL_ISCSI:
 612		return "iSCSI";
 613	default:
 614		break;
 615	}
 616
 617	return "Unknown";
 618}
 619
 620/* Start items for tcm_loop_port_cit */
 621
 622static int tcm_loop_port_link(
 623	struct se_portal_group *se_tpg,
 624	struct se_lun *lun)
 625{
 626	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 627				struct tcm_loop_tpg, tl_se_tpg);
 628	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 629
 630	atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
 631	/*
 632	 * Add Linux/SCSI struct scsi_device by HCTL
 633	 */
 634	scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 635
 636	pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 637	return 0;
 638}
 639
 640static void tcm_loop_port_unlink(
 641	struct se_portal_group *se_tpg,
 642	struct se_lun *se_lun)
 643{
 644	struct scsi_device *sd;
 645	struct tcm_loop_hba *tl_hba;
 646	struct tcm_loop_tpg *tl_tpg;
 647
 648	tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 649	tl_hba = tl_tpg->tl_hba;
 650
 651	sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 652				se_lun->unpacked_lun);
 653	if (!sd) {
 654		pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n",
 655		       0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 656		return;
 657	}
 658	/*
 659	 * Remove Linux/SCSI struct scsi_device by HCTL
 660	 */
 661	scsi_remove_device(sd);
 662	scsi_device_put(sd);
 663
 664	atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
 665
 666	pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 667}
 668
 669/* End items for tcm_loop_port_cit */
 670
 671static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
 672		struct config_item *item, char *page)
 673{
 674	struct se_portal_group *se_tpg = attrib_to_tpg(item);
 675	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 676						   tl_se_tpg);
 677
 678	return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
 679}
 680
 681static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
 682		struct config_item *item, const char *page, size_t count)
 683{
 684	struct se_portal_group *se_tpg = attrib_to_tpg(item);
 685	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
 686						   tl_se_tpg);
 687	unsigned long val;
 688	int ret = kstrtoul(page, 0, &val);
 689
 690	if (ret) {
 691		pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
 692		return ret;
 693	}
 694	if (val != 0 && val != 1 && val != 3) {
 695		pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
 696		return -EINVAL;
 697	}
 698	tl_tpg->tl_fabric_prot_type = val;
 699
 700	return count;
 701}
 702
 703CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
 704
 705static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
 706	&tcm_loop_tpg_attrib_attr_fabric_prot_type,
 707	NULL,
 708};
 709
 710/* Start items for tcm_loop_nexus_cit */
 711
 712static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
 713				  struct se_session *se_sess, void *p)
 714{
 715	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 716					struct tcm_loop_tpg, tl_se_tpg);
 717
 718	tl_tpg->tl_nexus = p;
 719	return 0;
 720}
 721
 722static int tcm_loop_make_nexus(
 723	struct tcm_loop_tpg *tl_tpg,
 724	const char *name)
 725{
 726	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 727	struct tcm_loop_nexus *tl_nexus;
 728	int ret;
 729
 730	if (tl_tpg->tl_nexus) {
 731		pr_debug("tl_tpg->tl_nexus already exists\n");
 732		return -EEXIST;
 733	}
 734
 735	tl_nexus = kzalloc(sizeof(*tl_nexus), GFP_KERNEL);
 736	if (!tl_nexus)
 737		return -ENOMEM;
 738
 739	tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0,
 740					TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
 741					name, tl_nexus, tcm_loop_alloc_sess_cb);
 742	if (IS_ERR(tl_nexus->se_sess)) {
 743		ret = PTR_ERR(tl_nexus->se_sess);
 744		kfree(tl_nexus);
 745		return ret;
 746	}
 747
 748	pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n",
 749		 tcm_loop_dump_proto_id(tl_hba), name);
 750	return 0;
 751}
 752
 753static int tcm_loop_drop_nexus(
 754	struct tcm_loop_tpg *tpg)
 755{
 756	struct se_session *se_sess;
 757	struct tcm_loop_nexus *tl_nexus;
 758
 759	tl_nexus = tpg->tl_nexus;
 760	if (!tl_nexus)
 761		return -ENODEV;
 762
 763	se_sess = tl_nexus->se_sess;
 764	if (!se_sess)
 765		return -ENODEV;
 766
 767	if (atomic_read(&tpg->tl_tpg_port_count)) {
 768		pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n",
 769		       atomic_read(&tpg->tl_tpg_port_count));
 770		return -EPERM;
 771	}
 772
 773	pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
 774		 tcm_loop_dump_proto_id(tpg->tl_hba),
 775		 tl_nexus->se_sess->se_node_acl->initiatorname);
 776	/*
 777	 * Release the SCSI I_T Nexus to the emulated Target Port
 778	 */
 779	target_remove_session(se_sess);
 780	tpg->tl_nexus = NULL;
 781	kfree(tl_nexus);
 782	return 0;
 783}
 784
 785/* End items for tcm_loop_nexus_cit */
 786
 787static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
 788{
 789	struct se_portal_group *se_tpg = to_tpg(item);
 790	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 791			struct tcm_loop_tpg, tl_se_tpg);
 792	struct tcm_loop_nexus *tl_nexus;
 793	ssize_t ret;
 794
 795	tl_nexus = tl_tpg->tl_nexus;
 796	if (!tl_nexus)
 797		return -ENODEV;
 798
 799	ret = snprintf(page, PAGE_SIZE, "%s\n",
 800		tl_nexus->se_sess->se_node_acl->initiatorname);
 801
 802	return ret;
 803}
 804
 805static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
 806		const char *page, size_t count)
 807{
 808	struct se_portal_group *se_tpg = to_tpg(item);
 809	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 810			struct tcm_loop_tpg, tl_se_tpg);
 811	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 812	unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
 813	int ret;
 814	/*
 815	 * Shutdown the active I_T nexus if 'NULL' is passed..
 816	 */
 817	if (!strncmp(page, "NULL", 4)) {
 818		ret = tcm_loop_drop_nexus(tl_tpg);
 819		return (!ret) ? count : ret;
 820	}
 821	/*
 822	 * Otherwise make sure the passed virtual Initiator port WWN matches
 823	 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
 824	 * tcm_loop_make_nexus()
 825	 */
 826	if (strlen(page) >= TL_WWN_ADDR_LEN) {
 827		pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
 828		       page, TL_WWN_ADDR_LEN);
 829		return -EINVAL;
 830	}
 831	snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
 832
 833	ptr = strstr(i_port, "naa.");
 834	if (ptr) {
 835		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
 836			pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
 837			       i_port, tcm_loop_dump_proto_id(tl_hba));
 838			return -EINVAL;
 839		}
 840		port_ptr = &i_port[0];
 841		goto check_newline;
 842	}
 843	ptr = strstr(i_port, "fc.");
 844	if (ptr) {
 845		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
 846			pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
 847			       i_port, tcm_loop_dump_proto_id(tl_hba));
 848			return -EINVAL;
 849		}
 850		port_ptr = &i_port[3]; /* Skip over "fc." */
 851		goto check_newline;
 852	}
 853	ptr = strstr(i_port, "iqn.");
 854	if (ptr) {
 855		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
 856			pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
 857			       i_port, tcm_loop_dump_proto_id(tl_hba));
 858			return -EINVAL;
 859		}
 860		port_ptr = &i_port[0];
 861		goto check_newline;
 862	}
 863	pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
 864	       i_port);
 865	return -EINVAL;
 866	/*
 867	 * Clear any trailing newline for the NAA WWN
 868	 */
 869check_newline:
 870	if (i_port[strlen(i_port)-1] == '\n')
 871		i_port[strlen(i_port)-1] = '\0';
 872
 873	ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
 874	if (ret < 0)
 875		return ret;
 876
 877	return count;
 878}
 879
 880static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
 881		char *page)
 882{
 883	struct se_portal_group *se_tpg = to_tpg(item);
 884	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 885			struct tcm_loop_tpg, tl_se_tpg);
 886	const char *status = NULL;
 887	ssize_t ret = -EINVAL;
 888
 889	switch (tl_tpg->tl_transport_status) {
 890	case TCM_TRANSPORT_ONLINE:
 891		status = "online";
 892		break;
 893	case TCM_TRANSPORT_OFFLINE:
 894		status = "offline";
 895		break;
 896	default:
 897		break;
 898	}
 899
 900	if (status)
 901		ret = snprintf(page, PAGE_SIZE, "%s\n", status);
 902
 903	return ret;
 904}
 905
 906static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
 907		const char *page, size_t count)
 908{
 909	struct se_portal_group *se_tpg = to_tpg(item);
 910	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 911			struct tcm_loop_tpg, tl_se_tpg);
 912
 913	if (!strncmp(page, "online", 6)) {
 914		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
 915		return count;
 916	}
 917	if (!strncmp(page, "offline", 7)) {
 918		tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
 919		if (tl_tpg->tl_nexus) {
 920			struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
 921
 922			core_allocate_nexus_loss_ua(tl_sess->se_node_acl);
 923		}
 924		return count;
 925	}
 926	return -EINVAL;
 927}
 928
 929static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
 930					 char *page)
 931{
 932	struct se_portal_group *se_tpg = to_tpg(item);
 933	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 934			struct tcm_loop_tpg, tl_se_tpg);
 935	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 936
 937	return snprintf(page, PAGE_SIZE, "%d:0:%d\n",
 938			tl_hba->sh->host_no, tl_tpg->tl_tpgt);
 939}
 940
 941CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
 942CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
 943CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
 944
 945static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
 946	&tcm_loop_tpg_attr_nexus,
 947	&tcm_loop_tpg_attr_transport_status,
 948	&tcm_loop_tpg_attr_address,
 949	NULL,
 950};
 951
 952/* Start items for tcm_loop_naa_cit */
 953
 954static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn,
 955						     const char *name)
 956{
 957	struct tcm_loop_hba *tl_hba = container_of(wwn,
 958			struct tcm_loop_hba, tl_hba_wwn);
 959	struct tcm_loop_tpg *tl_tpg;
 960	int ret;
 961	unsigned long tpgt;
 962
 963	if (strstr(name, "tpgt_") != name) {
 964		pr_err("Unable to locate \"tpgt_#\" directory group\n");
 965		return ERR_PTR(-EINVAL);
 966	}
 967	if (kstrtoul(name+5, 10, &tpgt))
 968		return ERR_PTR(-EINVAL);
 969
 970	if (tpgt >= TL_TPGS_PER_HBA) {
 971		pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
 972		       tpgt, TL_TPGS_PER_HBA);
 973		return ERR_PTR(-EINVAL);
 974	}
 975	tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
 976	tl_tpg->tl_hba = tl_hba;
 977	tl_tpg->tl_tpgt = tpgt;
 978	/*
 979	 * Register the tl_tpg as a emulated TCM Target Endpoint
 980	 */
 981	ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
 982	if (ret < 0)
 983		return ERR_PTR(-ENOMEM);
 984
 985	pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
 986		 tcm_loop_dump_proto_id(tl_hba),
 987		 config_item_name(&wwn->wwn_group.cg_item), tpgt);
 988	return &tl_tpg->tl_se_tpg;
 989}
 990
 991static void tcm_loop_drop_naa_tpg(
 992	struct se_portal_group *se_tpg)
 993{
 994	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
 995	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 996				struct tcm_loop_tpg, tl_se_tpg);
 997	struct tcm_loop_hba *tl_hba;
 998	unsigned short tpgt;
 999
1000	tl_hba = tl_tpg->tl_hba;
1001	tpgt = tl_tpg->tl_tpgt;
1002	/*
1003	 * Release the I_T Nexus for the Virtual target link if present
1004	 */
1005	tcm_loop_drop_nexus(tl_tpg);
1006	/*
1007	 * Deregister the tl_tpg as a emulated TCM Target Endpoint
1008	 */
1009	core_tpg_deregister(se_tpg);
1010
1011	tl_tpg->tl_hba = NULL;
1012	tl_tpg->tl_tpgt = 0;
1013
1014	pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
1015		 tcm_loop_dump_proto_id(tl_hba),
1016		 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1017}
1018
1019/* End items for tcm_loop_naa_cit */
1020
1021/* Start items for tcm_loop_cit */
1022
1023static struct se_wwn *tcm_loop_make_scsi_hba(
1024	struct target_fabric_configfs *tf,
1025	struct config_group *group,
1026	const char *name)
1027{
1028	struct tcm_loop_hba *tl_hba;
1029	struct Scsi_Host *sh;
1030	char *ptr;
1031	int ret, off = 0;
1032
1033	tl_hba = kzalloc(sizeof(*tl_hba), GFP_KERNEL);
1034	if (!tl_hba)
1035		return ERR_PTR(-ENOMEM);
1036
1037	/*
1038	 * Determine the emulated Protocol Identifier and Target Port Name
1039	 * based on the incoming configfs directory name.
1040	 */
1041	ptr = strstr(name, "naa.");
1042	if (ptr) {
1043		tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1044		goto check_len;
1045	}
1046	ptr = strstr(name, "fc.");
1047	if (ptr) {
1048		tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1049		off = 3; /* Skip over "fc." */
1050		goto check_len;
1051	}
1052	ptr = strstr(name, "iqn.");
1053	if (!ptr) {
1054		pr_err("Unable to locate prefix for emulated Target Port: %s\n",
1055		       name);
1056		ret = -EINVAL;
1057		goto out;
1058	}
1059	tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1060
1061check_len:
1062	if (strlen(name) >= TL_WWN_ADDR_LEN) {
1063		pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
1064		       name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN);
1065		ret = -EINVAL;
1066		goto out;
1067	}
1068	snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1069
1070	/*
1071	 * Call device_register(tl_hba->dev) to register the emulated
1072	 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1073	 * device_register() callbacks in tcm_loop_driver_probe()
1074	 */
1075	ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1076	if (ret)
1077		goto out;
1078
1079	sh = tl_hba->sh;
1080	tcm_loop_hba_no_cnt++;
1081	pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1082		 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1083	return &tl_hba->tl_hba_wwn;
1084out:
1085	kfree(tl_hba);
1086	return ERR_PTR(ret);
1087}
1088
1089static void tcm_loop_drop_scsi_hba(
1090	struct se_wwn *wwn)
1091{
1092	struct tcm_loop_hba *tl_hba = container_of(wwn,
1093				struct tcm_loop_hba, tl_hba_wwn);
1094
1095	pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1096		 tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1097		 tl_hba->sh->host_no);
1098	/*
1099	 * Call device_unregister() on the original tl_hba->dev.
1100	 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1101	 * release *tl_hba;
1102	 */
1103	device_unregister(&tl_hba->dev);
1104}
1105
1106/* Start items for tcm_loop_cit */
1107static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1108{
1109	return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1110}
1111
1112CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1113
1114static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1115	&tcm_loop_wwn_attr_version,
1116	NULL,
1117};
1118
1119/* End items for tcm_loop_cit */
1120
1121static const struct target_core_fabric_ops loop_ops = {
1122	.module				= THIS_MODULE,
1123	.fabric_name			= "loopback",
1124	.tpg_get_wwn			= tcm_loop_get_endpoint_wwn,
1125	.tpg_get_tag			= tcm_loop_get_tag,
1126	.tpg_check_demo_mode		= tcm_loop_check_demo_mode,
1127	.tpg_check_demo_mode_cache	= tcm_loop_check_demo_mode_cache,
1128	.tpg_check_demo_mode_write_protect =
1129				tcm_loop_check_demo_mode_write_protect,
1130	.tpg_check_prod_mode_write_protect =
1131				tcm_loop_check_prod_mode_write_protect,
1132	.tpg_check_prot_fabric_only	= tcm_loop_check_prot_fabric_only,
1133	.tpg_get_inst_index		= tcm_loop_get_inst_index,
1134	.check_stop_free		= tcm_loop_check_stop_free,
1135	.release_cmd			= tcm_loop_release_cmd,
1136	.sess_get_index			= tcm_loop_sess_get_index,
1137	.write_pending			= tcm_loop_write_pending,
1138	.set_default_node_attributes	= tcm_loop_set_default_node_attributes,
1139	.get_cmd_state			= tcm_loop_get_cmd_state,
1140	.queue_data_in			= tcm_loop_queue_data_in,
1141	.queue_status			= tcm_loop_queue_status,
1142	.queue_tm_rsp			= tcm_loop_queue_tm_rsp,
1143	.aborted_task			= tcm_loop_aborted_task,
1144	.fabric_make_wwn		= tcm_loop_make_scsi_hba,
1145	.fabric_drop_wwn		= tcm_loop_drop_scsi_hba,
1146	.fabric_make_tpg		= tcm_loop_make_naa_tpg,
1147	.fabric_drop_tpg		= tcm_loop_drop_naa_tpg,
1148	.fabric_post_link		= tcm_loop_port_link,
1149	.fabric_pre_unlink		= tcm_loop_port_unlink,
1150	.tfc_wwn_attrs			= tcm_loop_wwn_attrs,
1151	.tfc_tpg_base_attrs		= tcm_loop_tpg_attrs,
1152	.tfc_tpg_attrib_attrs		= tcm_loop_tpg_attrib_attrs,
1153};
1154
1155static int __init tcm_loop_fabric_init(void)
1156{
1157	int ret = -ENOMEM;
1158
 
 
 
 
1159	tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1160				sizeof(struct tcm_loop_cmd),
1161				__alignof__(struct tcm_loop_cmd),
1162				0, NULL);
1163	if (!tcm_loop_cmd_cache) {
1164		pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n");
1165		goto out;
1166	}
1167
1168	ret = tcm_loop_alloc_core_bus();
1169	if (ret)
1170		goto out_destroy_cache;
1171
1172	ret = target_register_template(&loop_ops);
1173	if (ret)
1174		goto out_release_core_bus;
1175
1176	return 0;
1177
1178out_release_core_bus:
1179	tcm_loop_release_core_bus();
1180out_destroy_cache:
1181	kmem_cache_destroy(tcm_loop_cmd_cache);
 
 
1182out:
1183	return ret;
1184}
1185
1186static void __exit tcm_loop_fabric_exit(void)
1187{
1188	target_unregister_template(&loop_ops);
1189	tcm_loop_release_core_bus();
1190	kmem_cache_destroy(tcm_loop_cmd_cache);
 
1191}
1192
1193MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1194MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1195MODULE_LICENSE("GPL");
1196module_init(tcm_loop_fabric_init);
1197module_exit(tcm_loop_fabric_exit);