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v3.1
   1/*******************************************************************************
   2 *
   3 * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4 * for emulated SAS initiator ports
   5 *
   6 * © Copyright 2011 RisingTide Systems LLC.
   7 *
   8 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9 *
  10 * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 ****************************************************************************/
  22
  23#include <linux/module.h>
  24#include <linux/moduleparam.h>
  25#include <linux/init.h>
  26#include <linux/slab.h>
  27#include <linux/types.h>
  28#include <linux/configfs.h>
  29#include <scsi/scsi.h>
  30#include <scsi/scsi_tcq.h>
  31#include <scsi/scsi_host.h>
  32#include <scsi/scsi_device.h>
  33#include <scsi/scsi_cmnd.h>
  34
  35#include <target/target_core_base.h>
  36#include <target/target_core_transport.h>
  37#include <target/target_core_fabric_ops.h>
  38#include <target/target_core_fabric_configfs.h>
  39#include <target/target_core_fabric_lib.h>
  40#include <target/target_core_configfs.h>
  41#include <target/target_core_device.h>
  42#include <target/target_core_tpg.h>
  43#include <target/target_core_tmr.h>
  44
  45#include "tcm_loop.h"
  46
  47#define to_tcm_loop_hba(hba)	container_of(hba, struct tcm_loop_hba, dev)
  48
  49/* Local pointer to allocated TCM configfs fabric module */
  50static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  51
 
  52static struct kmem_cache *tcm_loop_cmd_cache;
  53
  54static int tcm_loop_hba_no_cnt;
  55
  56/*
  57 * Allocate a tcm_loop cmd descriptor from target_core_mod code
  58 *
  59 * Can be called from interrupt context in tcm_loop_queuecommand() below
  60 */
  61static struct se_cmd *tcm_loop_allocate_core_cmd(
  62	struct tcm_loop_hba *tl_hba,
  63	struct se_portal_group *se_tpg,
  64	struct scsi_cmnd *sc)
  65{
  66	struct se_cmd *se_cmd;
  67	struct se_session *se_sess;
  68	struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus;
  69	struct tcm_loop_cmd *tl_cmd;
  70	int sam_task_attr;
  71
  72	if (!tl_nexus) {
  73		scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
  74				" does not exist\n");
  75		set_host_byte(sc, DID_ERROR);
  76		return NULL;
  77	}
  78	se_sess = tl_nexus->se_sess;
  79
  80	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
  81	if (!tl_cmd) {
  82		pr_err("Unable to allocate struct tcm_loop_cmd\n");
  83		set_host_byte(sc, DID_ERROR);
  84		return NULL;
  85	}
  86	se_cmd = &tl_cmd->tl_se_cmd;
  87	/*
  88	 * Save the pointer to struct scsi_cmnd *sc
  89	 */
  90	tl_cmd->sc = sc;
  91	/*
  92	 * Locate the SAM Task Attr from struct scsi_cmnd *
  93	 */
  94	if (sc->device->tagged_supported) {
  95		switch (sc->tag) {
  96		case HEAD_OF_QUEUE_TAG:
  97			sam_task_attr = MSG_HEAD_TAG;
  98			break;
  99		case ORDERED_QUEUE_TAG:
 100			sam_task_attr = MSG_ORDERED_TAG;
 101			break;
 102		default:
 103			sam_task_attr = MSG_SIMPLE_TAG;
 104			break;
 105		}
 106	} else
 107		sam_task_attr = MSG_SIMPLE_TAG;
 108
 109	/*
 110	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 111	 */
 112	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
 113			scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr,
 114			&tl_cmd->tl_sense_buf[0]);
 115
 116	/*
 117	 * Signal BIDI usage with T_TASK(cmd)->t_tasks_bidi
 118	 */
 119	if (scsi_bidi_cmnd(sc))
 120		se_cmd->t_tasks_bidi = 1;
 121	/*
 122	 * Locate the struct se_lun pointer and attach it to struct se_cmd
 123	 */
 124	if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
 125		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 126		set_host_byte(sc, DID_NO_CONNECT);
 127		return NULL;
 128	}
 129
 130	return se_cmd;
 131}
 132
 133/*
 134 * Called by struct target_core_fabric_ops->new_cmd_map()
 135 *
 136 * Always called in process context.  A non zero return value
 137 * here will signal to handle an exception based on the return code.
 138 */
 139static int tcm_loop_new_cmd_map(struct se_cmd *se_cmd)
 140{
 141	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 142				struct tcm_loop_cmd, tl_se_cmd);
 143	struct scsi_cmnd *sc = tl_cmd->sc;
 144	struct scatterlist *sgl_bidi = NULL;
 145	u32 sgl_bidi_count = 0;
 146	int ret;
 147	/*
 148	 * Allocate the necessary tasks to complete the received CDB+data
 149	 */
 150	ret = transport_generic_allocate_tasks(se_cmd, sc->cmnd);
 151	if (ret == -ENOMEM) {
 152		/* Out of Resources */
 153		return PYX_TRANSPORT_LU_COMM_FAILURE;
 154	} else if (ret == -EINVAL) {
 155		/*
 156		 * Handle case for SAM_STAT_RESERVATION_CONFLICT
 157		 */
 158		if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
 159			return PYX_TRANSPORT_RESERVATION_CONFLICT;
 160		/*
 161		 * Otherwise, return SAM_STAT_CHECK_CONDITION and return
 162		 * sense data.
 163		 */
 164		return PYX_TRANSPORT_USE_SENSE_REASON;
 165	}
 166
 167	/*
 168	 * For BIDI commands, pass in the extra READ buffer
 169	 * to transport_generic_map_mem_to_cmd() below..
 170	 */
 171	if (se_cmd->t_tasks_bidi) {
 172		struct scsi_data_buffer *sdb = scsi_in(sc);
 173
 174		sgl_bidi = sdb->table.sgl;
 175		sgl_bidi_count = sdb->table.nents;
 176	}
 177
 178	/* Tell the core about our preallocated memory */
 179	ret = transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),
 180			scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);
 181	if (ret < 0)
 182		return PYX_TRANSPORT_LU_COMM_FAILURE;
 183
 184	return 0;
 185}
 186
 187/*
 188 * Called from struct target_core_fabric_ops->check_stop_free()
 189 */
 190static void tcm_loop_check_stop_free(struct se_cmd *se_cmd)
 191{
 192	/*
 193	 * Do not release struct se_cmd's containing a valid TMR
 194	 * pointer.  These will be released directly in tcm_loop_device_reset()
 195	 * with transport_generic_free_cmd().
 196	 */
 197	if (se_cmd->se_tmr_req)
 198		return;
 199	/*
 200	 * Release the struct se_cmd, which will make a callback to release
 201	 * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
 202	 */
 203	transport_generic_free_cmd(se_cmd, 0, 0);
 
 204}
 205
 206static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
 207{
 208	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 209				struct tcm_loop_cmd, tl_se_cmd);
 210
 211	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 212}
 213
 214static int tcm_loop_proc_info(struct Scsi_Host *host, char *buffer,
 215				char **start, off_t offset,
 216				int length, int inout)
 217{
 218	return sprintf(buffer, "tcm_loop_proc_info()\n");
 219}
 220
 221static int tcm_loop_driver_probe(struct device *);
 222static int tcm_loop_driver_remove(struct device *);
 223
 224static int pseudo_lld_bus_match(struct device *dev,
 225				struct device_driver *dev_driver)
 226{
 227	return 1;
 228}
 229
 230static struct bus_type tcm_loop_lld_bus = {
 231	.name			= "tcm_loop_bus",
 232	.match			= pseudo_lld_bus_match,
 233	.probe			= tcm_loop_driver_probe,
 234	.remove			= tcm_loop_driver_remove,
 235};
 236
 237static struct device_driver tcm_loop_driverfs = {
 238	.name			= "tcm_loop",
 239	.bus			= &tcm_loop_lld_bus,
 240};
 241/*
 242 * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 243 */
 244struct device *tcm_loop_primary;
 245
 246/*
 247 * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
 248 * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
 249 */
 250static int tcm_loop_change_queue_depth(
 251	struct scsi_device *sdev,
 252	int depth,
 253	int reason)
 254{
 255	switch (reason) {
 256	case SCSI_QDEPTH_DEFAULT:
 257		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 258		break;
 259	case SCSI_QDEPTH_QFULL:
 260		scsi_track_queue_full(sdev, depth);
 261		break;
 262	case SCSI_QDEPTH_RAMP_UP:
 263		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 264		break;
 265	default:
 266		return -EOPNOTSUPP;
 267	}
 268	return sdev->queue_depth;
 269}
 270
 271/*
 272 * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data
 273 * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs)
 274 */
 275static int tcm_loop_queuecommand(
 276	struct Scsi_Host *sh,
 277	struct scsi_cmnd *sc)
 278{
 279	struct se_cmd *se_cmd;
 280	struct se_portal_group *se_tpg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 281	struct tcm_loop_hba *tl_hba;
 282	struct tcm_loop_tpg *tl_tpg;
 
 
 
 283
 284	pr_debug("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
 285		" scsi_buf_len: %u\n", sc->device->host->host_no,
 286		sc->device->id, sc->device->channel, sc->device->lun,
 287		sc->cmnd[0], scsi_bufflen(sc));
 288	/*
 289	 * Locate the tcm_loop_hba_t pointer
 290	 */
 291	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 292	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 293	se_tpg = &tl_tpg->tl_se_tpg;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 294	/*
 295	 * Determine the SAM Task Attribute and allocate tl_cmd and
 296	 * tl_cmd->tl_se_cmd from TCM infrastructure
 
 
 
 
 297	 */
 298	se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
 299	if (!se_cmd) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 300		sc->scsi_done(sc);
 301		return 0;
 302	}
 303	/*
 304	 * Queue up the newly allocated to be processed in TCM thread context.
 305	*/
 306	transport_generic_handle_cdb_map(se_cmd);
 307	return 0;
 308}
 309
 310/*
 311 * Called from SCSI EH process context to issue a LUN_RESET TMR
 312 * to struct scsi_device
 313 */
 314static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 315{
 316	struct se_cmd *se_cmd = NULL;
 317	struct se_portal_group *se_tpg;
 318	struct se_session *se_sess;
 319	struct tcm_loop_cmd *tl_cmd = NULL;
 320	struct tcm_loop_hba *tl_hba;
 321	struct tcm_loop_nexus *tl_nexus;
 322	struct tcm_loop_tmr *tl_tmr = NULL;
 323	struct tcm_loop_tpg *tl_tpg;
 324	int ret = FAILED;
 325	/*
 326	 * Locate the tcm_loop_hba_t pointer
 327	 */
 328	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 329	/*
 330	 * Locate the tl_nexus and se_sess pointers
 331	 */
 332	tl_nexus = tl_hba->tl_nexus;
 333	if (!tl_nexus) {
 334		pr_err("Unable to perform device reset without"
 335				" active I_T Nexus\n");
 336		return FAILED;
 337	}
 338	se_sess = tl_nexus->se_sess;
 339	/*
 340	 * Locate the tl_tpg and se_tpg pointers from TargetID in sc->device->id
 341	 */
 342	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 343	se_tpg = &tl_tpg->tl_se_tpg;
 344
 345	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 346	if (!tl_cmd) {
 347		pr_err("Unable to allocate memory for tl_cmd\n");
 348		return FAILED;
 349	}
 350
 351	tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 352	if (!tl_tmr) {
 353		pr_err("Unable to allocate memory for tl_tmr\n");
 354		goto release;
 355	}
 356	init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 357
 358	se_cmd = &tl_cmd->tl_se_cmd;
 359	/*
 360	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 361	 */
 362	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 363				DMA_NONE, MSG_SIMPLE_TAG,
 364				&tl_cmd->tl_sense_buf[0]);
 365	/*
 366	 * Allocate the LUN_RESET TMR
 367	 */
 368	se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, tl_tmr,
 369				TMR_LUN_RESET);
 370	if (IS_ERR(se_cmd->se_tmr_req))
 371		goto release;
 372	/*
 373	 * Locate the underlying TCM struct se_lun from sc->device->lun
 374	 */
 375	if (transport_lookup_tmr_lun(se_cmd, sc->device->lun) < 0)
 376		goto release;
 377	/*
 378	 * Queue the TMR to TCM Core and sleep waiting for tcm_loop_queue_tm_rsp()
 379	 * to wake us up.
 380	 */
 381	transport_generic_handle_tmr(se_cmd);
 382	wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 383	/*
 384	 * The TMR LUN_RESET has completed, check the response status and
 385	 * then release allocations.
 386	 */
 387	ret = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
 388		SUCCESS : FAILED;
 389release:
 390	if (se_cmd)
 391		transport_generic_free_cmd(se_cmd, 1, 0);
 392	else
 393		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 394	kfree(tl_tmr);
 395	return ret;
 396}
 397
 398static int tcm_loop_slave_alloc(struct scsi_device *sd)
 399{
 400	set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 401	return 0;
 402}
 403
 404static int tcm_loop_slave_configure(struct scsi_device *sd)
 405{
 406	return 0;
 407}
 408
 409static struct scsi_host_template tcm_loop_driver_template = {
 410	.proc_info		= tcm_loop_proc_info,
 411	.proc_name		= "tcm_loopback",
 412	.name			= "TCM_Loopback",
 413	.queuecommand		= tcm_loop_queuecommand,
 414	.change_queue_depth	= tcm_loop_change_queue_depth,
 415	.eh_device_reset_handler = tcm_loop_device_reset,
 416	.can_queue		= TL_SCSI_CAN_QUEUE,
 417	.this_id		= -1,
 418	.sg_tablesize		= TL_SCSI_SG_TABLESIZE,
 419	.cmd_per_lun		= TL_SCSI_CMD_PER_LUN,
 420	.max_sectors		= TL_SCSI_MAX_SECTORS,
 421	.use_clustering		= DISABLE_CLUSTERING,
 422	.slave_alloc		= tcm_loop_slave_alloc,
 423	.slave_configure	= tcm_loop_slave_configure,
 424	.module			= THIS_MODULE,
 425};
 426
 427static int tcm_loop_driver_probe(struct device *dev)
 428{
 429	struct tcm_loop_hba *tl_hba;
 430	struct Scsi_Host *sh;
 431	int error;
 432
 433	tl_hba = to_tcm_loop_hba(dev);
 434
 435	sh = scsi_host_alloc(&tcm_loop_driver_template,
 436			sizeof(struct tcm_loop_hba));
 437	if (!sh) {
 438		pr_err("Unable to allocate struct scsi_host\n");
 439		return -ENODEV;
 440	}
 441	tl_hba->sh = sh;
 442
 443	/*
 444	 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 445	 */
 446	*((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 447	/*
 448	 * Setup single ID, Channel and LUN for now..
 449	 */
 450	sh->max_id = 2;
 451	sh->max_lun = 0;
 452	sh->max_channel = 0;
 453	sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 454
 455	error = scsi_add_host(sh, &tl_hba->dev);
 456	if (error) {
 457		pr_err("%s: scsi_add_host failed\n", __func__);
 458		scsi_host_put(sh);
 459		return -ENODEV;
 460	}
 461	return 0;
 462}
 463
 464static int tcm_loop_driver_remove(struct device *dev)
 465{
 466	struct tcm_loop_hba *tl_hba;
 467	struct Scsi_Host *sh;
 468
 469	tl_hba = to_tcm_loop_hba(dev);
 470	sh = tl_hba->sh;
 471
 472	scsi_remove_host(sh);
 473	scsi_host_put(sh);
 474	return 0;
 475}
 476
 477static void tcm_loop_release_adapter(struct device *dev)
 478{
 479	struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 480
 481	kfree(tl_hba);
 482}
 483
 484/*
 485 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 486 */
 487static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 488{
 489	int ret;
 490
 491	tl_hba->dev.bus = &tcm_loop_lld_bus;
 492	tl_hba->dev.parent = tcm_loop_primary;
 493	tl_hba->dev.release = &tcm_loop_release_adapter;
 494	dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 495
 496	ret = device_register(&tl_hba->dev);
 497	if (ret) {
 498		pr_err("device_register() failed for"
 499				" tl_hba->dev: %d\n", ret);
 500		return -ENODEV;
 501	}
 502
 503	return 0;
 504}
 505
 506/*
 507 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 508 * tcm_loop SCSI bus.
 509 */
 510static int tcm_loop_alloc_core_bus(void)
 511{
 512	int ret;
 513
 514	tcm_loop_primary = root_device_register("tcm_loop_0");
 515	if (IS_ERR(tcm_loop_primary)) {
 516		pr_err("Unable to allocate tcm_loop_primary\n");
 517		return PTR_ERR(tcm_loop_primary);
 518	}
 519
 520	ret = bus_register(&tcm_loop_lld_bus);
 521	if (ret) {
 522		pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 523		goto dev_unreg;
 524	}
 525
 526	ret = driver_register(&tcm_loop_driverfs);
 527	if (ret) {
 528		pr_err("driver_register() failed for"
 529				"tcm_loop_driverfs\n");
 530		goto bus_unreg;
 531	}
 532
 533	pr_debug("Initialized TCM Loop Core Bus\n");
 534	return ret;
 535
 536bus_unreg:
 537	bus_unregister(&tcm_loop_lld_bus);
 538dev_unreg:
 539	root_device_unregister(tcm_loop_primary);
 540	return ret;
 541}
 542
 543static void tcm_loop_release_core_bus(void)
 544{
 545	driver_unregister(&tcm_loop_driverfs);
 546	bus_unregister(&tcm_loop_lld_bus);
 547	root_device_unregister(tcm_loop_primary);
 548
 549	pr_debug("Releasing TCM Loop Core BUS\n");
 550}
 551
 552static char *tcm_loop_get_fabric_name(void)
 553{
 554	return "loopback";
 555}
 556
 557static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 558{
 559	struct tcm_loop_tpg *tl_tpg =
 560			(struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 561	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 562	/*
 563	 * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 564	 * time based on the protocol dependent prefix of the passed configfs group.
 565	 *
 566	 * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 567	 * ProtocolID using target_core_fabric_lib.c symbols.
 568	 */
 569	switch (tl_hba->tl_proto_id) {
 570	case SCSI_PROTOCOL_SAS:
 571		return sas_get_fabric_proto_ident(se_tpg);
 572	case SCSI_PROTOCOL_FCP:
 573		return fc_get_fabric_proto_ident(se_tpg);
 574	case SCSI_PROTOCOL_ISCSI:
 575		return iscsi_get_fabric_proto_ident(se_tpg);
 576	default:
 577		pr_err("Unknown tl_proto_id: 0x%02x, using"
 578			" SAS emulation\n", tl_hba->tl_proto_id);
 579		break;
 580	}
 581
 582	return sas_get_fabric_proto_ident(se_tpg);
 583}
 584
 585static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 586{
 587	struct tcm_loop_tpg *tl_tpg =
 588		(struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 589	/*
 590	 * Return the passed NAA identifier for the SAS Target Port
 591	 */
 592	return &tl_tpg->tl_hba->tl_wwn_address[0];
 593}
 594
 595static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 596{
 597	struct tcm_loop_tpg *tl_tpg =
 598		(struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 599	/*
 600	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 601	 * to represent the SCSI Target Port.
 602	 */
 603	return tl_tpg->tl_tpgt;
 604}
 605
 606static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 607{
 608	return 1;
 609}
 610
 611static u32 tcm_loop_get_pr_transport_id(
 612	struct se_portal_group *se_tpg,
 613	struct se_node_acl *se_nacl,
 614	struct t10_pr_registration *pr_reg,
 615	int *format_code,
 616	unsigned char *buf)
 617{
 618	struct tcm_loop_tpg *tl_tpg =
 619			(struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 620	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 621
 622	switch (tl_hba->tl_proto_id) {
 623	case SCSI_PROTOCOL_SAS:
 624		return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 625					format_code, buf);
 626	case SCSI_PROTOCOL_FCP:
 627		return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 628					format_code, buf);
 629	case SCSI_PROTOCOL_ISCSI:
 630		return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 631					format_code, buf);
 632	default:
 633		pr_err("Unknown tl_proto_id: 0x%02x, using"
 634			" SAS emulation\n", tl_hba->tl_proto_id);
 635		break;
 636	}
 637
 638	return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 639			format_code, buf);
 640}
 641
 642static u32 tcm_loop_get_pr_transport_id_len(
 643	struct se_portal_group *se_tpg,
 644	struct se_node_acl *se_nacl,
 645	struct t10_pr_registration *pr_reg,
 646	int *format_code)
 647{
 648	struct tcm_loop_tpg *tl_tpg =
 649			(struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 650	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 651
 652	switch (tl_hba->tl_proto_id) {
 653	case SCSI_PROTOCOL_SAS:
 654		return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 655					format_code);
 656	case SCSI_PROTOCOL_FCP:
 657		return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 658					format_code);
 659	case SCSI_PROTOCOL_ISCSI:
 660		return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 661					format_code);
 662	default:
 663		pr_err("Unknown tl_proto_id: 0x%02x, using"
 664			" SAS emulation\n", tl_hba->tl_proto_id);
 665		break;
 666	}
 667
 668	return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 669			format_code);
 670}
 671
 672/*
 673 * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 674 * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 675 */
 676static char *tcm_loop_parse_pr_out_transport_id(
 677	struct se_portal_group *se_tpg,
 678	const char *buf,
 679	u32 *out_tid_len,
 680	char **port_nexus_ptr)
 681{
 682	struct tcm_loop_tpg *tl_tpg =
 683			(struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
 684	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 685
 686	switch (tl_hba->tl_proto_id) {
 687	case SCSI_PROTOCOL_SAS:
 688		return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 689					port_nexus_ptr);
 690	case SCSI_PROTOCOL_FCP:
 691		return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 692					port_nexus_ptr);
 693	case SCSI_PROTOCOL_ISCSI:
 694		return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 695					port_nexus_ptr);
 696	default:
 697		pr_err("Unknown tl_proto_id: 0x%02x, using"
 698			" SAS emulation\n", tl_hba->tl_proto_id);
 699		break;
 700	}
 701
 702	return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 703			port_nexus_ptr);
 704}
 705
 706/*
 707 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 708 * based upon the incoming fabric dependent SCSI Initiator Port
 709 */
 710static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 711{
 712	return 1;
 713}
 714
 715static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 716{
 717	return 0;
 718}
 719
 720/*
 721 * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 722 * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 723 */
 724static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 725{
 726	return 0;
 727}
 728
 729/*
 730 * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 731 * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 732 * It has been added here as a nop for target_fabric_tf_ops_check()
 733 */
 734static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 735{
 736	return 0;
 737}
 738
 739static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 740	struct se_portal_group *se_tpg)
 741{
 742	struct tcm_loop_nacl *tl_nacl;
 743
 744	tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 745	if (!tl_nacl) {
 746		pr_err("Unable to allocate struct tcm_loop_nacl\n");
 747		return NULL;
 748	}
 749
 750	return &tl_nacl->se_node_acl;
 751}
 752
 753static void tcm_loop_tpg_release_fabric_acl(
 754	struct se_portal_group *se_tpg,
 755	struct se_node_acl *se_nacl)
 756{
 757	struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 758				struct tcm_loop_nacl, se_node_acl);
 759
 760	kfree(tl_nacl);
 761}
 762
 763static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 764{
 765	return 1;
 766}
 767
 768static int tcm_loop_is_state_remove(struct se_cmd *se_cmd)
 769{
 770	/*
 771	 * Assume struct scsi_cmnd is not in remove state..
 772	 */
 773	return 0;
 774}
 775
 776static int tcm_loop_sess_logged_in(struct se_session *se_sess)
 777{
 778	/*
 779	 * Assume that TL Nexus is always active
 780	 */
 781	return 1;
 782}
 783
 784static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 785{
 786	return 1;
 787}
 788
 789static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 790{
 791	return;
 792}
 793
 794static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 795{
 796	return 1;
 797}
 798
 799static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 800{
 801	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 802			struct tcm_loop_cmd, tl_se_cmd);
 803
 804	return tl_cmd->sc_cmd_state;
 805}
 806
 807static int tcm_loop_shutdown_session(struct se_session *se_sess)
 808{
 809	return 0;
 810}
 811
 812static void tcm_loop_close_session(struct se_session *se_sess)
 813{
 814	return;
 815};
 816
 817static void tcm_loop_stop_session(
 818	struct se_session *se_sess,
 819	int sess_sleep,
 820	int conn_sleep)
 821{
 822	return;
 823}
 824
 825static void tcm_loop_fall_back_to_erl0(struct se_session *se_sess)
 826{
 827	return;
 828}
 829
 830static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 831{
 832	/*
 833	 * Since Linux/SCSI has already sent down a struct scsi_cmnd
 834	 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 835	 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 836	 * format with transport_generic_map_mem_to_cmd().
 837	 *
 838	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
 839	 * object execution queue.
 840	 */
 841	transport_generic_process_write(se_cmd);
 842	return 0;
 843}
 844
 845static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 846{
 847	return 0;
 848}
 849
 850static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 851{
 852	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 853				struct tcm_loop_cmd, tl_se_cmd);
 854	struct scsi_cmnd *sc = tl_cmd->sc;
 855
 856	pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 857		     " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 858
 859	sc->result = SAM_STAT_GOOD;
 860	set_host_byte(sc, DID_OK);
 
 
 
 861	sc->scsi_done(sc);
 862	return 0;
 863}
 864
 865static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 866{
 867	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 868				struct tcm_loop_cmd, tl_se_cmd);
 869	struct scsi_cmnd *sc = tl_cmd->sc;
 870
 871	pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 872			" cdb: 0x%02x\n", sc, sc->cmnd[0]);
 873
 874	if (se_cmd->sense_buffer &&
 875	   ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 876	    (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 877
 878		memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 879				SCSI_SENSE_BUFFERSIZE);
 880		sc->result = SAM_STAT_CHECK_CONDITION;
 881		set_driver_byte(sc, DRIVER_SENSE);
 882	} else
 883		sc->result = se_cmd->scsi_status;
 884
 885	set_host_byte(sc, DID_OK);
 
 
 
 886	sc->scsi_done(sc);
 887	return 0;
 888}
 889
 890static int tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 891{
 892	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 893	struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 894	/*
 895	 * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 896	 * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 897	 */
 898	atomic_set(&tl_tmr->tmr_complete, 1);
 899	wake_up(&tl_tmr->tl_tmr_wait);
 900	return 0;
 901}
 902
 903static u16 tcm_loop_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_length)
 904{
 905	return 0;
 906}
 907
 908static u16 tcm_loop_get_fabric_sense_len(void)
 909{
 910	return 0;
 911}
 912
 913static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 914{
 915	switch (tl_hba->tl_proto_id) {
 916	case SCSI_PROTOCOL_SAS:
 917		return "SAS";
 918	case SCSI_PROTOCOL_FCP:
 919		return "FCP";
 920	case SCSI_PROTOCOL_ISCSI:
 921		return "iSCSI";
 922	default:
 923		break;
 924	}
 925
 926	return "Unknown";
 927}
 928
 929/* Start items for tcm_loop_port_cit */
 930
 931static int tcm_loop_port_link(
 932	struct se_portal_group *se_tpg,
 933	struct se_lun *lun)
 934{
 935	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 936				struct tcm_loop_tpg, tl_se_tpg);
 937	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 938
 939	atomic_inc(&tl_tpg->tl_tpg_port_count);
 940	smp_mb__after_atomic_inc();
 941	/*
 942	 * Add Linux/SCSI struct scsi_device by HCTL
 943	 */
 944	scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 945
 946	pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 947	return 0;
 948}
 949
 950static void tcm_loop_port_unlink(
 951	struct se_portal_group *se_tpg,
 952	struct se_lun *se_lun)
 953{
 954	struct scsi_device *sd;
 955	struct tcm_loop_hba *tl_hba;
 956	struct tcm_loop_tpg *tl_tpg;
 957
 958	tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 959	tl_hba = tl_tpg->tl_hba;
 960
 961	sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 962				se_lun->unpacked_lun);
 963	if (!sd) {
 964		pr_err("Unable to locate struct scsi_device for %d:%d:"
 965			"%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 966		return;
 967	}
 968	/*
 969	 * Remove Linux/SCSI struct scsi_device by HCTL
 970	 */
 971	scsi_remove_device(sd);
 972	scsi_device_put(sd);
 973
 974	atomic_dec(&tl_tpg->tl_tpg_port_count);
 975	smp_mb__after_atomic_dec();
 976
 977	pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 978}
 979
 980/* End items for tcm_loop_port_cit */
 981
 982/* Start items for tcm_loop_nexus_cit */
 983
 984static int tcm_loop_make_nexus(
 985	struct tcm_loop_tpg *tl_tpg,
 986	const char *name)
 987{
 988	struct se_portal_group *se_tpg;
 989	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 990	struct tcm_loop_nexus *tl_nexus;
 991	int ret = -ENOMEM;
 992
 993	if (tl_tpg->tl_hba->tl_nexus) {
 994		pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
 995		return -EEXIST;
 996	}
 997	se_tpg = &tl_tpg->tl_se_tpg;
 998
 999	tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
1000	if (!tl_nexus) {
1001		pr_err("Unable to allocate struct tcm_loop_nexus\n");
1002		return -ENOMEM;
1003	}
1004	/*
1005	 * Initialize the struct se_session pointer
1006	 */
1007	tl_nexus->se_sess = transport_init_session();
1008	if (IS_ERR(tl_nexus->se_sess)) {
1009		ret = PTR_ERR(tl_nexus->se_sess);
1010		goto out;
1011	}
1012	/*
1013	 * Since we are running in 'demo mode' this call with generate a
1014	 * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
1015	 * Initiator port name of the passed configfs group 'name'.
1016	 */
1017	tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1018				se_tpg, (unsigned char *)name);
1019	if (!tl_nexus->se_sess->se_node_acl) {
1020		transport_free_session(tl_nexus->se_sess);
1021		goto out;
1022	}
1023	/*
1024	 * Now, register the SAS I_T Nexus as active with the call to
1025	 * transport_register_session()
1026	 */
1027	__transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1028			tl_nexus->se_sess, tl_nexus);
1029	tl_tpg->tl_hba->tl_nexus = tl_nexus;
1030	pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1031		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1032		name);
1033	return 0;
1034
1035out:
1036	kfree(tl_nexus);
1037	return ret;
1038}
1039
1040static int tcm_loop_drop_nexus(
1041	struct tcm_loop_tpg *tpg)
1042{
1043	struct se_session *se_sess;
1044	struct tcm_loop_nexus *tl_nexus;
1045	struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1046
1047	tl_nexus = tpg->tl_hba->tl_nexus;
1048	if (!tl_nexus)
1049		return -ENODEV;
1050
1051	se_sess = tl_nexus->se_sess;
1052	if (!se_sess)
1053		return -ENODEV;
1054
1055	if (atomic_read(&tpg->tl_tpg_port_count)) {
1056		pr_err("Unable to remove TCM_Loop I_T Nexus with"
1057			" active TPG port count: %d\n",
1058			atomic_read(&tpg->tl_tpg_port_count));
1059		return -EPERM;
1060	}
1061
1062	pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1063		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1064		tl_nexus->se_sess->se_node_acl->initiatorname);
1065	/*
1066	 * Release the SCSI I_T Nexus to the emulated SAS Target Port
1067	 */
1068	transport_deregister_session(tl_nexus->se_sess);
1069	tpg->tl_hba->tl_nexus = NULL;
1070	kfree(tl_nexus);
1071	return 0;
1072}
1073
1074/* End items for tcm_loop_nexus_cit */
1075
1076static ssize_t tcm_loop_tpg_show_nexus(
1077	struct se_portal_group *se_tpg,
1078	char *page)
1079{
1080	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1081			struct tcm_loop_tpg, tl_se_tpg);
1082	struct tcm_loop_nexus *tl_nexus;
1083	ssize_t ret;
1084
1085	tl_nexus = tl_tpg->tl_hba->tl_nexus;
1086	if (!tl_nexus)
1087		return -ENODEV;
1088
1089	ret = snprintf(page, PAGE_SIZE, "%s\n",
1090		tl_nexus->se_sess->se_node_acl->initiatorname);
1091
1092	return ret;
1093}
1094
1095static ssize_t tcm_loop_tpg_store_nexus(
1096	struct se_portal_group *se_tpg,
1097	const char *page,
1098	size_t count)
1099{
1100	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1101			struct tcm_loop_tpg, tl_se_tpg);
1102	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1103	unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1104	int ret;
1105	/*
1106	 * Shutdown the active I_T nexus if 'NULL' is passed..
1107	 */
1108	if (!strncmp(page, "NULL", 4)) {
1109		ret = tcm_loop_drop_nexus(tl_tpg);
1110		return (!ret) ? count : ret;
1111	}
1112	/*
1113	 * Otherwise make sure the passed virtual Initiator port WWN matches
1114	 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1115	 * tcm_loop_make_nexus()
1116	 */
1117	if (strlen(page) >= TL_WWN_ADDR_LEN) {
1118		pr_err("Emulated NAA Sas Address: %s, exceeds"
1119				" max: %d\n", page, TL_WWN_ADDR_LEN);
1120		return -EINVAL;
1121	}
1122	snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1123
1124	ptr = strstr(i_port, "naa.");
1125	if (ptr) {
1126		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1127			pr_err("Passed SAS Initiator Port %s does not"
1128				" match target port protoid: %s\n", i_port,
1129				tcm_loop_dump_proto_id(tl_hba));
1130			return -EINVAL;
1131		}
1132		port_ptr = &i_port[0];
1133		goto check_newline;
1134	}
1135	ptr = strstr(i_port, "fc.");
1136	if (ptr) {
1137		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1138			pr_err("Passed FCP Initiator Port %s does not"
1139				" match target port protoid: %s\n", i_port,
1140				tcm_loop_dump_proto_id(tl_hba));
1141			return -EINVAL;
1142		}
1143		port_ptr = &i_port[3]; /* Skip over "fc." */
1144		goto check_newline;
1145	}
1146	ptr = strstr(i_port, "iqn.");
1147	if (ptr) {
1148		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1149			pr_err("Passed iSCSI Initiator Port %s does not"
1150				" match target port protoid: %s\n", i_port,
1151				tcm_loop_dump_proto_id(tl_hba));
1152			return -EINVAL;
1153		}
1154		port_ptr = &i_port[0];
1155		goto check_newline;
1156	}
1157	pr_err("Unable to locate prefix for emulated Initiator Port:"
1158			" %s\n", i_port);
1159	return -EINVAL;
1160	/*
1161	 * Clear any trailing newline for the NAA WWN
1162	 */
1163check_newline:
1164	if (i_port[strlen(i_port)-1] == '\n')
1165		i_port[strlen(i_port)-1] = '\0';
1166
1167	ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1168	if (ret < 0)
1169		return ret;
1170
1171	return count;
1172}
1173
1174TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1175
1176static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1177	&tcm_loop_tpg_nexus.attr,
1178	NULL,
1179};
1180
1181/* Start items for tcm_loop_naa_cit */
1182
1183struct se_portal_group *tcm_loop_make_naa_tpg(
1184	struct se_wwn *wwn,
1185	struct config_group *group,
1186	const char *name)
1187{
1188	struct tcm_loop_hba *tl_hba = container_of(wwn,
1189			struct tcm_loop_hba, tl_hba_wwn);
1190	struct tcm_loop_tpg *tl_tpg;
1191	char *tpgt_str, *end_ptr;
1192	int ret;
1193	unsigned short int tpgt;
1194
1195	tpgt_str = strstr(name, "tpgt_");
1196	if (!tpgt_str) {
1197		pr_err("Unable to locate \"tpgt_#\" directory"
1198				" group\n");
1199		return ERR_PTR(-EINVAL);
1200	}
1201	tpgt_str += 5; /* Skip ahead of "tpgt_" */
1202	tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1203
1204	if (tpgt >= TL_TPGS_PER_HBA) {
1205		pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1206				" %u\n", tpgt, TL_TPGS_PER_HBA);
1207		return ERR_PTR(-EINVAL);
1208	}
1209	tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1210	tl_tpg->tl_hba = tl_hba;
1211	tl_tpg->tl_tpgt = tpgt;
1212	/*
1213	 * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1214	 */
1215	ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1216			wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1217			TRANSPORT_TPG_TYPE_NORMAL);
1218	if (ret < 0)
1219		return ERR_PTR(-ENOMEM);
1220
1221	pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1222		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1223		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1224
1225	return &tl_tpg->tl_se_tpg;
1226}
1227
1228void tcm_loop_drop_naa_tpg(
1229	struct se_portal_group *se_tpg)
1230{
1231	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1232	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1233				struct tcm_loop_tpg, tl_se_tpg);
1234	struct tcm_loop_hba *tl_hba;
1235	unsigned short tpgt;
1236
1237	tl_hba = tl_tpg->tl_hba;
1238	tpgt = tl_tpg->tl_tpgt;
1239	/*
1240	 * Release the I_T Nexus for the Virtual SAS link if present
1241	 */
1242	tcm_loop_drop_nexus(tl_tpg);
1243	/*
1244	 * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1245	 */
1246	core_tpg_deregister(se_tpg);
1247
 
 
 
1248	pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1249		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1250		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1251}
1252
1253/* End items for tcm_loop_naa_cit */
1254
1255/* Start items for tcm_loop_cit */
1256
1257struct se_wwn *tcm_loop_make_scsi_hba(
1258	struct target_fabric_configfs *tf,
1259	struct config_group *group,
1260	const char *name)
1261{
1262	struct tcm_loop_hba *tl_hba;
1263	struct Scsi_Host *sh;
1264	char *ptr;
1265	int ret, off = 0;
1266
1267	tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1268	if (!tl_hba) {
1269		pr_err("Unable to allocate struct tcm_loop_hba\n");
1270		return ERR_PTR(-ENOMEM);
1271	}
1272	/*
1273	 * Determine the emulated Protocol Identifier and Target Port Name
1274	 * based on the incoming configfs directory name.
1275	 */
1276	ptr = strstr(name, "naa.");
1277	if (ptr) {
1278		tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1279		goto check_len;
1280	}
1281	ptr = strstr(name, "fc.");
1282	if (ptr) {
1283		tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1284		off = 3; /* Skip over "fc." */
1285		goto check_len;
1286	}
1287	ptr = strstr(name, "iqn.");
1288	if (!ptr) {
1289		pr_err("Unable to locate prefix for emulated Target "
1290				"Port: %s\n", name);
1291		ret = -EINVAL;
1292		goto out;
1293	}
1294	tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1295
1296check_len:
1297	if (strlen(name) >= TL_WWN_ADDR_LEN) {
1298		pr_err("Emulated NAA %s Address: %s, exceeds"
1299			" max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1300			TL_WWN_ADDR_LEN);
1301		ret = -EINVAL;
1302		goto out;
1303	}
1304	snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1305
1306	/*
1307	 * Call device_register(tl_hba->dev) to register the emulated
1308	 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1309	 * device_register() callbacks in tcm_loop_driver_probe()
1310	 */
1311	ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1312	if (ret)
1313		goto out;
1314
1315	sh = tl_hba->sh;
1316	tcm_loop_hba_no_cnt++;
1317	pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1318		" %s Address: %s at Linux/SCSI Host ID: %d\n",
1319		tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1320
1321	return &tl_hba->tl_hba_wwn;
1322out:
1323	kfree(tl_hba);
1324	return ERR_PTR(ret);
1325}
1326
1327void tcm_loop_drop_scsi_hba(
1328	struct se_wwn *wwn)
1329{
1330	struct tcm_loop_hba *tl_hba = container_of(wwn,
1331				struct tcm_loop_hba, tl_hba_wwn);
1332	int host_no = tl_hba->sh->host_no;
 
 
 
1333	/*
1334	 * Call device_unregister() on the original tl_hba->dev.
1335	 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1336	 * release *tl_hba;
1337	 */
1338	device_unregister(&tl_hba->dev);
1339
1340	pr_debug("TCM_Loop_ConfigFS: Deallocated emulated Target"
1341		" SAS Address: %s at Linux/SCSI Host ID: %d\n",
1342		config_item_name(&wwn->wwn_group.cg_item), host_no);
1343}
1344
1345/* Start items for tcm_loop_cit */
1346static ssize_t tcm_loop_wwn_show_attr_version(
1347	struct target_fabric_configfs *tf,
1348	char *page)
1349{
1350	return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1351}
1352
1353TF_WWN_ATTR_RO(tcm_loop, version);
1354
1355static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1356	&tcm_loop_wwn_version.attr,
1357	NULL,
1358};
1359
1360/* End items for tcm_loop_cit */
1361
1362static int tcm_loop_register_configfs(void)
1363{
1364	struct target_fabric_configfs *fabric;
1365	struct config_group *tf_cg;
1366	int ret;
1367	/*
1368	 * Set the TCM Loop HBA counter to zero
1369	 */
1370	tcm_loop_hba_no_cnt = 0;
1371	/*
1372	 * Register the top level struct config_item_type with TCM core
1373	 */
1374	fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1375	if (IS_ERR(fabric)) {
1376		pr_err("tcm_loop_register_configfs() failed!\n");
1377		return PTR_ERR(fabric);
1378	}
1379	/*
1380	 * Setup the fabric API of function pointers used by target_core_mod
1381	 */
1382	fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1383	fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1384	fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1385	fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1386	fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1387	fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1388	fabric->tf_ops.tpg_get_pr_transport_id_len =
1389					&tcm_loop_get_pr_transport_id_len;
1390	fabric->tf_ops.tpg_parse_pr_out_transport_id =
1391					&tcm_loop_parse_pr_out_transport_id;
1392	fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1393	fabric->tf_ops.tpg_check_demo_mode_cache =
1394					&tcm_loop_check_demo_mode_cache;
1395	fabric->tf_ops.tpg_check_demo_mode_write_protect =
1396					&tcm_loop_check_demo_mode_write_protect;
1397	fabric->tf_ops.tpg_check_prod_mode_write_protect =
1398					&tcm_loop_check_prod_mode_write_protect;
1399	/*
1400	 * The TCM loopback fabric module runs in demo-mode to a local
1401	 * virtual SCSI device, so fabric dependent initator ACLs are
1402	 * not required.
1403	 */
1404	fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1405	fabric->tf_ops.tpg_release_fabric_acl =
1406					&tcm_loop_tpg_release_fabric_acl;
1407	fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1408	/*
1409	 * Used for setting up remaining TCM resources in process context
1410	 */
1411	fabric->tf_ops.new_cmd_map = &tcm_loop_new_cmd_map;
1412	fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1413	fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1414	fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1415	fabric->tf_ops.close_session = &tcm_loop_close_session;
1416	fabric->tf_ops.stop_session = &tcm_loop_stop_session;
1417	fabric->tf_ops.fall_back_to_erl0 = &tcm_loop_fall_back_to_erl0;
1418	fabric->tf_ops.sess_logged_in = &tcm_loop_sess_logged_in;
1419	fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1420	fabric->tf_ops.sess_get_initiator_sid = NULL;
1421	fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1422	fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1423	/*
1424	 * Not used for TCM loopback
1425	 */
1426	fabric->tf_ops.set_default_node_attributes =
1427					&tcm_loop_set_default_node_attributes;
1428	fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1429	fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1430	fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1431	fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1432	fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1433	fabric->tf_ops.set_fabric_sense_len = &tcm_loop_set_fabric_sense_len;
1434	fabric->tf_ops.get_fabric_sense_len = &tcm_loop_get_fabric_sense_len;
1435	fabric->tf_ops.is_state_remove = &tcm_loop_is_state_remove;
1436
1437	tf_cg = &fabric->tf_group;
1438	/*
1439	 * Setup function pointers for generic logic in target_core_fabric_configfs.c
1440	 */
1441	fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1442	fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1443	fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1444	fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1445	/*
1446	 * fabric_post_link() and fabric_pre_unlink() are used for
1447	 * registration and release of TCM Loop Virtual SCSI LUNs.
1448	 */
1449	fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1450	fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1451	fabric->tf_ops.fabric_make_np = NULL;
1452	fabric->tf_ops.fabric_drop_np = NULL;
1453	/*
1454	 * Setup default attribute lists for various fabric->tf_cit_tmpl
1455	 */
1456	TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1457	TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1458	TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1459	TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1460	TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1461	/*
1462	 * Once fabric->tf_ops has been setup, now register the fabric for
1463	 * use within TCM
1464	 */
1465	ret = target_fabric_configfs_register(fabric);
1466	if (ret < 0) {
1467		pr_err("target_fabric_configfs_register() for"
1468				" TCM_Loop failed!\n");
1469		target_fabric_configfs_free(fabric);
1470		return -1;
1471	}
1472	/*
1473	 * Setup our local pointer to *fabric.
1474	 */
1475	tcm_loop_fabric_configfs = fabric;
1476	pr_debug("TCM_LOOP[0] - Set fabric ->"
1477			" tcm_loop_fabric_configfs\n");
1478	return 0;
1479}
1480
1481static void tcm_loop_deregister_configfs(void)
1482{
1483	if (!tcm_loop_fabric_configfs)
1484		return;
1485
1486	target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1487	tcm_loop_fabric_configfs = NULL;
1488	pr_debug("TCM_LOOP[0] - Cleared"
1489				" tcm_loop_fabric_configfs\n");
1490}
1491
1492static int __init tcm_loop_fabric_init(void)
1493{
1494	int ret;
 
 
 
 
1495
1496	tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1497				sizeof(struct tcm_loop_cmd),
1498				__alignof__(struct tcm_loop_cmd),
1499				0, NULL);
1500	if (!tcm_loop_cmd_cache) {
1501		pr_debug("kmem_cache_create() for"
1502			" tcm_loop_cmd_cache failed\n");
1503		return -ENOMEM;
1504	}
1505
1506	ret = tcm_loop_alloc_core_bus();
1507	if (ret)
1508		return ret;
1509
1510	ret = tcm_loop_register_configfs();
1511	if (ret) {
1512		tcm_loop_release_core_bus();
1513		return ret;
1514	}
1515
1516	return 0;
 
 
 
 
 
 
 
 
 
1517}
1518
1519static void __exit tcm_loop_fabric_exit(void)
1520{
1521	tcm_loop_deregister_configfs();
1522	tcm_loop_release_core_bus();
1523	kmem_cache_destroy(tcm_loop_cmd_cache);
 
1524}
1525
1526MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1527MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1528MODULE_LICENSE("GPL");
1529module_init(tcm_loop_fabric_init);
1530module_exit(tcm_loop_fabric_exit);
v3.5.6
   1/*******************************************************************************
   2 *
   3 * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
   4 * for emulated SAS initiator ports
   5 *
   6 * © Copyright 2011 RisingTide Systems LLC.
   7 *
   8 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   9 *
  10 * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 ****************************************************************************/
  22
  23#include <linux/module.h>
  24#include <linux/moduleparam.h>
  25#include <linux/init.h>
  26#include <linux/slab.h>
  27#include <linux/types.h>
  28#include <linux/configfs.h>
  29#include <scsi/scsi.h>
  30#include <scsi/scsi_tcq.h>
  31#include <scsi/scsi_host.h>
  32#include <scsi/scsi_device.h>
  33#include <scsi/scsi_cmnd.h>
  34
  35#include <target/target_core_base.h>
  36#include <target/target_core_fabric.h>
 
  37#include <target/target_core_fabric_configfs.h>
 
  38#include <target/target_core_configfs.h>
 
 
 
  39
  40#include "tcm_loop.h"
  41
  42#define to_tcm_loop_hba(hba)	container_of(hba, struct tcm_loop_hba, dev)
  43
  44/* Local pointer to allocated TCM configfs fabric module */
  45static struct target_fabric_configfs *tcm_loop_fabric_configfs;
  46
  47static struct workqueue_struct *tcm_loop_workqueue;
  48static struct kmem_cache *tcm_loop_cmd_cache;
  49
  50static int tcm_loop_hba_no_cnt;
  51
  52static int tcm_loop_queue_status(struct se_cmd *se_cmd);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  53
  54/*
  55 * Called from struct target_core_fabric_ops->check_stop_free()
  56 */
  57static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
  58{
  59	/*
  60	 * Do not release struct se_cmd's containing a valid TMR
  61	 * pointer.  These will be released directly in tcm_loop_device_reset()
  62	 * with transport_generic_free_cmd().
  63	 */
  64	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
  65		return 0;
  66	/*
  67	 * Release the struct se_cmd, which will make a callback to release
  68	 * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
  69	 */
  70	transport_generic_free_cmd(se_cmd, 0);
  71	return 1;
  72}
  73
  74static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
  75{
  76	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
  77				struct tcm_loop_cmd, tl_se_cmd);
  78
  79	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
  80}
  81
  82static int tcm_loop_proc_info(struct Scsi_Host *host, char *buffer,
  83				char **start, off_t offset,
  84				int length, int inout)
  85{
  86	return sprintf(buffer, "tcm_loop_proc_info()\n");
  87}
  88
  89static int tcm_loop_driver_probe(struct device *);
  90static int tcm_loop_driver_remove(struct device *);
  91
  92static int pseudo_lld_bus_match(struct device *dev,
  93				struct device_driver *dev_driver)
  94{
  95	return 1;
  96}
  97
  98static struct bus_type tcm_loop_lld_bus = {
  99	.name			= "tcm_loop_bus",
 100	.match			= pseudo_lld_bus_match,
 101	.probe			= tcm_loop_driver_probe,
 102	.remove			= tcm_loop_driver_remove,
 103};
 104
 105static struct device_driver tcm_loop_driverfs = {
 106	.name			= "tcm_loop",
 107	.bus			= &tcm_loop_lld_bus,
 108};
 109/*
 110 * Used with root_device_register() in tcm_loop_alloc_core_bus() below
 111 */
 112struct device *tcm_loop_primary;
 113
 114/*
 115 * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
 116 * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
 117 */
 118static int tcm_loop_change_queue_depth(
 119	struct scsi_device *sdev,
 120	int depth,
 121	int reason)
 122{
 123	switch (reason) {
 124	case SCSI_QDEPTH_DEFAULT:
 125		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 126		break;
 127	case SCSI_QDEPTH_QFULL:
 128		scsi_track_queue_full(sdev, depth);
 129		break;
 130	case SCSI_QDEPTH_RAMP_UP:
 131		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 132		break;
 133	default:
 134		return -EOPNOTSUPP;
 135	}
 136	return sdev->queue_depth;
 137}
 138
 139/*
 140 * Locate the SAM Task Attr from struct scsi_cmnd *
 
 141 */
 142static int tcm_loop_sam_attr(struct scsi_cmnd *sc)
 
 
 143{
 144	if (sc->device->tagged_supported) {
 145		switch (sc->tag) {
 146		case HEAD_OF_QUEUE_TAG:
 147			return MSG_HEAD_TAG;
 148		case ORDERED_QUEUE_TAG:
 149			return MSG_ORDERED_TAG;
 150		default:
 151			break;
 152		}
 153	}
 154
 155	return MSG_SIMPLE_TAG;
 156}
 157
 158static void tcm_loop_submission_work(struct work_struct *work)
 159{
 160	struct tcm_loop_cmd *tl_cmd =
 161		container_of(work, struct tcm_loop_cmd, work);
 162	struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
 163	struct scsi_cmnd *sc = tl_cmd->sc;
 164	struct tcm_loop_nexus *tl_nexus;
 165	struct tcm_loop_hba *tl_hba;
 166	struct tcm_loop_tpg *tl_tpg;
 167	struct scatterlist *sgl_bidi = NULL;
 168	u32 sgl_bidi_count = 0;
 169	int ret;
 170
 
 
 
 
 
 
 
 171	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 172	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 173
 174	/*
 175	 * Ensure that this tl_tpg reference from the incoming sc->device->id
 176	 * has already been configured via tcm_loop_make_naa_tpg().
 177	 */
 178	if (!tl_tpg->tl_hba) {
 179		set_host_byte(sc, DID_NO_CONNECT);
 180		goto out_done;
 181	}
 182
 183	tl_nexus = tl_hba->tl_nexus;
 184	if (!tl_nexus) {
 185		scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
 186				" does not exist\n");
 187		set_host_byte(sc, DID_ERROR);
 188		goto out_done;
 189	}
 190
 191	transport_init_se_cmd(se_cmd, tl_tpg->tl_se_tpg.se_tpg_tfo,
 192			tl_nexus->se_sess,
 193			scsi_bufflen(sc), sc->sc_data_direction,
 194			tcm_loop_sam_attr(sc), &tl_cmd->tl_sense_buf[0]);
 195
 196	if (scsi_bidi_cmnd(sc)) {
 197		struct scsi_data_buffer *sdb = scsi_in(sc);
 198
 199		sgl_bidi = sdb->table.sgl;
 200		sgl_bidi_count = sdb->table.nents;
 201		se_cmd->se_cmd_flags |= SCF_BIDI;
 202
 203	}
 204
 205	if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
 206		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 207		set_host_byte(sc, DID_NO_CONNECT);
 208		goto out_done;
 209	}
 210
 211	/*
 212	 * Because some userspace code via scsi-generic do not memset their
 213	 * associated read buffers, go ahead and do that here for type
 214	 * SCF_SCSI_CONTROL_SG_IO_CDB.  Also note that this is currently
 215	 * guaranteed to be a single SGL for SCF_SCSI_CONTROL_SG_IO_CDB
 216	 * by target core in target_setup_cmd_from_cdb() ->
 217	 * transport_generic_cmd_sequencer().
 218	 */
 219	if (se_cmd->se_cmd_flags & SCF_SCSI_CONTROL_SG_IO_CDB &&
 220	    se_cmd->data_direction == DMA_FROM_DEVICE) {
 221		struct scatterlist *sg = scsi_sglist(sc);
 222		unsigned char *buf = kmap(sg_page(sg)) + sg->offset;
 223
 224		if (buf != NULL) {
 225			memset(buf, 0, sg->length);
 226			kunmap(sg_page(sg));
 227		}
 228	}
 229
 230	ret = target_setup_cmd_from_cdb(se_cmd, sc->cmnd);
 231	if (ret == -ENOMEM) {
 232		transport_send_check_condition_and_sense(se_cmd,
 233				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 234		transport_generic_free_cmd(se_cmd, 0);
 235		return;
 236	} else if (ret < 0) {
 237		if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
 238			tcm_loop_queue_status(se_cmd);
 239		else
 240			transport_send_check_condition_and_sense(se_cmd,
 241					se_cmd->scsi_sense_reason, 0);
 242		transport_generic_free_cmd(se_cmd, 0);
 243		return;
 244	}
 245
 246	ret = transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),
 247			scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);
 248	if (ret) {
 249		transport_send_check_condition_and_sense(se_cmd,
 250					se_cmd->scsi_sense_reason, 0);
 251		transport_generic_free_cmd(se_cmd, 0);
 252		return;
 253	}
 254	transport_handle_cdb_direct(se_cmd);
 255	return;
 256
 257out_done:
 258	sc->scsi_done(sc);
 259	return;
 260}
 261
 262/*
 263 * ->queuecommand can be and usually is called from interrupt context, so
 264 * defer the actual submission to a workqueue.
 265 */
 266static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 267{
 268	struct tcm_loop_cmd *tl_cmd;
 269
 270	pr_debug("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
 271		" scsi_buf_len: %u\n", sc->device->host->host_no,
 272		sc->device->id, sc->device->channel, sc->device->lun,
 273		sc->cmnd[0], scsi_bufflen(sc));
 274
 275	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
 276	if (!tl_cmd) {
 277		pr_err("Unable to allocate struct tcm_loop_cmd\n");
 278		set_host_byte(sc, DID_ERROR);
 279		sc->scsi_done(sc);
 280		return 0;
 281	}
 282
 283	tl_cmd->sc = sc;
 284	INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
 285	queue_work(tcm_loop_workqueue, &tl_cmd->work);
 286	return 0;
 287}
 288
 289/*
 290 * Called from SCSI EH process context to issue a LUN_RESET TMR
 291 * to struct scsi_device
 292 */
 293static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 294{
 295	struct se_cmd *se_cmd = NULL;
 296	struct se_portal_group *se_tpg;
 297	struct se_session *se_sess;
 298	struct tcm_loop_cmd *tl_cmd = NULL;
 299	struct tcm_loop_hba *tl_hba;
 300	struct tcm_loop_nexus *tl_nexus;
 301	struct tcm_loop_tmr *tl_tmr = NULL;
 302	struct tcm_loop_tpg *tl_tpg;
 303	int ret = FAILED, rc;
 304	/*
 305	 * Locate the tcm_loop_hba_t pointer
 306	 */
 307	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
 308	/*
 309	 * Locate the tl_nexus and se_sess pointers
 310	 */
 311	tl_nexus = tl_hba->tl_nexus;
 312	if (!tl_nexus) {
 313		pr_err("Unable to perform device reset without"
 314				" active I_T Nexus\n");
 315		return FAILED;
 316	}
 317	se_sess = tl_nexus->se_sess;
 318	/*
 319	 * Locate the tl_tpg and se_tpg pointers from TargetID in sc->device->id
 320	 */
 321	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
 322	se_tpg = &tl_tpg->tl_se_tpg;
 323
 324	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
 325	if (!tl_cmd) {
 326		pr_err("Unable to allocate memory for tl_cmd\n");
 327		return FAILED;
 328	}
 329
 330	tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
 331	if (!tl_tmr) {
 332		pr_err("Unable to allocate memory for tl_tmr\n");
 333		goto release;
 334	}
 335	init_waitqueue_head(&tl_tmr->tl_tmr_wait);
 336
 337	se_cmd = &tl_cmd->tl_se_cmd;
 338	/*
 339	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
 340	 */
 341	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 342				DMA_NONE, MSG_SIMPLE_TAG,
 343				&tl_cmd->tl_sense_buf[0]);
 344
 345	rc = core_tmr_alloc_req(se_cmd, tl_tmr, TMR_LUN_RESET, GFP_KERNEL);
 346	if (rc < 0)
 
 
 
 347		goto release;
 348	/*
 349	 * Locate the underlying TCM struct se_lun from sc->device->lun
 350	 */
 351	if (transport_lookup_tmr_lun(se_cmd, sc->device->lun) < 0)
 352		goto release;
 353	/*
 354	 * Queue the TMR to TCM Core and sleep waiting for tcm_loop_queue_tm_rsp()
 355	 * to wake us up.
 356	 */
 357	transport_generic_handle_tmr(se_cmd);
 358	wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
 359	/*
 360	 * The TMR LUN_RESET has completed, check the response status and
 361	 * then release allocations.
 362	 */
 363	ret = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
 364		SUCCESS : FAILED;
 365release:
 366	if (se_cmd)
 367		transport_generic_free_cmd(se_cmd, 1);
 368	else
 369		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
 370	kfree(tl_tmr);
 371	return ret;
 372}
 373
 374static int tcm_loop_slave_alloc(struct scsi_device *sd)
 375{
 376	set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
 377	return 0;
 378}
 379
 380static int tcm_loop_slave_configure(struct scsi_device *sd)
 381{
 382	return 0;
 383}
 384
 385static struct scsi_host_template tcm_loop_driver_template = {
 386	.proc_info		= tcm_loop_proc_info,
 387	.proc_name		= "tcm_loopback",
 388	.name			= "TCM_Loopback",
 389	.queuecommand		= tcm_loop_queuecommand,
 390	.change_queue_depth	= tcm_loop_change_queue_depth,
 391	.eh_device_reset_handler = tcm_loop_device_reset,
 392	.can_queue		= 1024,
 393	.this_id		= -1,
 394	.sg_tablesize		= 256,
 395	.cmd_per_lun		= 1024,
 396	.max_sectors		= 0xFFFF,
 397	.use_clustering		= DISABLE_CLUSTERING,
 398	.slave_alloc		= tcm_loop_slave_alloc,
 399	.slave_configure	= tcm_loop_slave_configure,
 400	.module			= THIS_MODULE,
 401};
 402
 403static int tcm_loop_driver_probe(struct device *dev)
 404{
 405	struct tcm_loop_hba *tl_hba;
 406	struct Scsi_Host *sh;
 407	int error;
 408
 409	tl_hba = to_tcm_loop_hba(dev);
 410
 411	sh = scsi_host_alloc(&tcm_loop_driver_template,
 412			sizeof(struct tcm_loop_hba));
 413	if (!sh) {
 414		pr_err("Unable to allocate struct scsi_host\n");
 415		return -ENODEV;
 416	}
 417	tl_hba->sh = sh;
 418
 419	/*
 420	 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
 421	 */
 422	*((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
 423	/*
 424	 * Setup single ID, Channel and LUN for now..
 425	 */
 426	sh->max_id = 2;
 427	sh->max_lun = 0;
 428	sh->max_channel = 0;
 429	sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
 430
 431	error = scsi_add_host(sh, &tl_hba->dev);
 432	if (error) {
 433		pr_err("%s: scsi_add_host failed\n", __func__);
 434		scsi_host_put(sh);
 435		return -ENODEV;
 436	}
 437	return 0;
 438}
 439
 440static int tcm_loop_driver_remove(struct device *dev)
 441{
 442	struct tcm_loop_hba *tl_hba;
 443	struct Scsi_Host *sh;
 444
 445	tl_hba = to_tcm_loop_hba(dev);
 446	sh = tl_hba->sh;
 447
 448	scsi_remove_host(sh);
 449	scsi_host_put(sh);
 450	return 0;
 451}
 452
 453static void tcm_loop_release_adapter(struct device *dev)
 454{
 455	struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
 456
 457	kfree(tl_hba);
 458}
 459
 460/*
 461 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
 462 */
 463static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
 464{
 465	int ret;
 466
 467	tl_hba->dev.bus = &tcm_loop_lld_bus;
 468	tl_hba->dev.parent = tcm_loop_primary;
 469	tl_hba->dev.release = &tcm_loop_release_adapter;
 470	dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
 471
 472	ret = device_register(&tl_hba->dev);
 473	if (ret) {
 474		pr_err("device_register() failed for"
 475				" tl_hba->dev: %d\n", ret);
 476		return -ENODEV;
 477	}
 478
 479	return 0;
 480}
 481
 482/*
 483 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
 484 * tcm_loop SCSI bus.
 485 */
 486static int tcm_loop_alloc_core_bus(void)
 487{
 488	int ret;
 489
 490	tcm_loop_primary = root_device_register("tcm_loop_0");
 491	if (IS_ERR(tcm_loop_primary)) {
 492		pr_err("Unable to allocate tcm_loop_primary\n");
 493		return PTR_ERR(tcm_loop_primary);
 494	}
 495
 496	ret = bus_register(&tcm_loop_lld_bus);
 497	if (ret) {
 498		pr_err("bus_register() failed for tcm_loop_lld_bus\n");
 499		goto dev_unreg;
 500	}
 501
 502	ret = driver_register(&tcm_loop_driverfs);
 503	if (ret) {
 504		pr_err("driver_register() failed for"
 505				"tcm_loop_driverfs\n");
 506		goto bus_unreg;
 507	}
 508
 509	pr_debug("Initialized TCM Loop Core Bus\n");
 510	return ret;
 511
 512bus_unreg:
 513	bus_unregister(&tcm_loop_lld_bus);
 514dev_unreg:
 515	root_device_unregister(tcm_loop_primary);
 516	return ret;
 517}
 518
 519static void tcm_loop_release_core_bus(void)
 520{
 521	driver_unregister(&tcm_loop_driverfs);
 522	bus_unregister(&tcm_loop_lld_bus);
 523	root_device_unregister(tcm_loop_primary);
 524
 525	pr_debug("Releasing TCM Loop Core BUS\n");
 526}
 527
 528static char *tcm_loop_get_fabric_name(void)
 529{
 530	return "loopback";
 531}
 532
 533static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 534{
 535	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 
 536	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 537	/*
 538	 * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
 539	 * time based on the protocol dependent prefix of the passed configfs group.
 540	 *
 541	 * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
 542	 * ProtocolID using target_core_fabric_lib.c symbols.
 543	 */
 544	switch (tl_hba->tl_proto_id) {
 545	case SCSI_PROTOCOL_SAS:
 546		return sas_get_fabric_proto_ident(se_tpg);
 547	case SCSI_PROTOCOL_FCP:
 548		return fc_get_fabric_proto_ident(se_tpg);
 549	case SCSI_PROTOCOL_ISCSI:
 550		return iscsi_get_fabric_proto_ident(se_tpg);
 551	default:
 552		pr_err("Unknown tl_proto_id: 0x%02x, using"
 553			" SAS emulation\n", tl_hba->tl_proto_id);
 554		break;
 555	}
 556
 557	return sas_get_fabric_proto_ident(se_tpg);
 558}
 559
 560static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
 561{
 562	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 
 563	/*
 564	 * Return the passed NAA identifier for the SAS Target Port
 565	 */
 566	return &tl_tpg->tl_hba->tl_wwn_address[0];
 567}
 568
 569static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
 570{
 571	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 
 572	/*
 573	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
 574	 * to represent the SCSI Target Port.
 575	 */
 576	return tl_tpg->tl_tpgt;
 577}
 578
 579static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
 580{
 581	return 1;
 582}
 583
 584static u32 tcm_loop_get_pr_transport_id(
 585	struct se_portal_group *se_tpg,
 586	struct se_node_acl *se_nacl,
 587	struct t10_pr_registration *pr_reg,
 588	int *format_code,
 589	unsigned char *buf)
 590{
 591	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 
 592	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 593
 594	switch (tl_hba->tl_proto_id) {
 595	case SCSI_PROTOCOL_SAS:
 596		return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 597					format_code, buf);
 598	case SCSI_PROTOCOL_FCP:
 599		return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 600					format_code, buf);
 601	case SCSI_PROTOCOL_ISCSI:
 602		return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 603					format_code, buf);
 604	default:
 605		pr_err("Unknown tl_proto_id: 0x%02x, using"
 606			" SAS emulation\n", tl_hba->tl_proto_id);
 607		break;
 608	}
 609
 610	return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 611			format_code, buf);
 612}
 613
 614static u32 tcm_loop_get_pr_transport_id_len(
 615	struct se_portal_group *se_tpg,
 616	struct se_node_acl *se_nacl,
 617	struct t10_pr_registration *pr_reg,
 618	int *format_code)
 619{
 620	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 
 621	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 622
 623	switch (tl_hba->tl_proto_id) {
 624	case SCSI_PROTOCOL_SAS:
 625		return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 626					format_code);
 627	case SCSI_PROTOCOL_FCP:
 628		return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 629					format_code);
 630	case SCSI_PROTOCOL_ISCSI:
 631		return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 632					format_code);
 633	default:
 634		pr_err("Unknown tl_proto_id: 0x%02x, using"
 635			" SAS emulation\n", tl_hba->tl_proto_id);
 636		break;
 637	}
 638
 639	return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 640			format_code);
 641}
 642
 643/*
 644 * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
 645 * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
 646 */
 647static char *tcm_loop_parse_pr_out_transport_id(
 648	struct se_portal_group *se_tpg,
 649	const char *buf,
 650	u32 *out_tid_len,
 651	char **port_nexus_ptr)
 652{
 653	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
 
 654	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 655
 656	switch (tl_hba->tl_proto_id) {
 657	case SCSI_PROTOCOL_SAS:
 658		return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 659					port_nexus_ptr);
 660	case SCSI_PROTOCOL_FCP:
 661		return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 662					port_nexus_ptr);
 663	case SCSI_PROTOCOL_ISCSI:
 664		return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 665					port_nexus_ptr);
 666	default:
 667		pr_err("Unknown tl_proto_id: 0x%02x, using"
 668			" SAS emulation\n", tl_hba->tl_proto_id);
 669		break;
 670	}
 671
 672	return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 673			port_nexus_ptr);
 674}
 675
 676/*
 677 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
 678 * based upon the incoming fabric dependent SCSI Initiator Port
 679 */
 680static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
 681{
 682	return 1;
 683}
 684
 685static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
 686{
 687	return 0;
 688}
 689
 690/*
 691 * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
 692 * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
 693 */
 694static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
 695{
 696	return 0;
 697}
 698
 699/*
 700 * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
 701 * never be called for TCM_Loop by target_core_fabric_configfs.c code.
 702 * It has been added here as a nop for target_fabric_tf_ops_check()
 703 */
 704static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
 705{
 706	return 0;
 707}
 708
 709static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
 710	struct se_portal_group *se_tpg)
 711{
 712	struct tcm_loop_nacl *tl_nacl;
 713
 714	tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
 715	if (!tl_nacl) {
 716		pr_err("Unable to allocate struct tcm_loop_nacl\n");
 717		return NULL;
 718	}
 719
 720	return &tl_nacl->se_node_acl;
 721}
 722
 723static void tcm_loop_tpg_release_fabric_acl(
 724	struct se_portal_group *se_tpg,
 725	struct se_node_acl *se_nacl)
 726{
 727	struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
 728				struct tcm_loop_nacl, se_node_acl);
 729
 730	kfree(tl_nacl);
 731}
 732
 733static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
 734{
 735	return 1;
 736}
 737
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 738static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
 739{
 740	return 1;
 741}
 742
 743static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
 744{
 745	return;
 746}
 747
 748static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
 749{
 750	return 1;
 751}
 752
 753static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
 754{
 755	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 756			struct tcm_loop_cmd, tl_se_cmd);
 757
 758	return tl_cmd->sc_cmd_state;
 759}
 760
 761static int tcm_loop_shutdown_session(struct se_session *se_sess)
 762{
 763	return 0;
 764}
 765
 766static void tcm_loop_close_session(struct se_session *se_sess)
 767{
 768	return;
 769};
 770
 
 
 
 
 
 
 
 
 
 
 
 
 
 771static int tcm_loop_write_pending(struct se_cmd *se_cmd)
 772{
 773	/*
 774	 * Since Linux/SCSI has already sent down a struct scsi_cmnd
 775	 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
 776	 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
 777	 * format with transport_generic_map_mem_to_cmd().
 778	 *
 779	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
 780	 * object execution queue.
 781	 */
 782	transport_generic_process_write(se_cmd);
 783	return 0;
 784}
 785
 786static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
 787{
 788	return 0;
 789}
 790
 791static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
 792{
 793	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 794				struct tcm_loop_cmd, tl_se_cmd);
 795	struct scsi_cmnd *sc = tl_cmd->sc;
 796
 797	pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
 798		     " cdb: 0x%02x\n", sc, sc->cmnd[0]);
 799
 800	sc->result = SAM_STAT_GOOD;
 801	set_host_byte(sc, DID_OK);
 802	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 803	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 804		scsi_set_resid(sc, se_cmd->residual_count);
 805	sc->scsi_done(sc);
 806	return 0;
 807}
 808
 809static int tcm_loop_queue_status(struct se_cmd *se_cmd)
 810{
 811	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
 812				struct tcm_loop_cmd, tl_se_cmd);
 813	struct scsi_cmnd *sc = tl_cmd->sc;
 814
 815	pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
 816			" cdb: 0x%02x\n", sc, sc->cmnd[0]);
 817
 818	if (se_cmd->sense_buffer &&
 819	   ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
 820	    (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
 821
 822		memcpy(sc->sense_buffer, se_cmd->sense_buffer,
 823				SCSI_SENSE_BUFFERSIZE);
 824		sc->result = SAM_STAT_CHECK_CONDITION;
 825		set_driver_byte(sc, DRIVER_SENSE);
 826	} else
 827		sc->result = se_cmd->scsi_status;
 828
 829	set_host_byte(sc, DID_OK);
 830	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
 831	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
 832		scsi_set_resid(sc, se_cmd->residual_count);
 833	sc->scsi_done(sc);
 834	return 0;
 835}
 836
 837static int tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
 838{
 839	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
 840	struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
 841	/*
 842	 * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
 843	 * and wake up the wait_queue_head_t in tcm_loop_device_reset()
 844	 */
 845	atomic_set(&tl_tmr->tmr_complete, 1);
 846	wake_up(&tl_tmr->tl_tmr_wait);
 847	return 0;
 848}
 849
 850static u16 tcm_loop_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_length)
 851{
 852	return 0;
 853}
 854
 855static u16 tcm_loop_get_fabric_sense_len(void)
 856{
 857	return 0;
 858}
 859
 860static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
 861{
 862	switch (tl_hba->tl_proto_id) {
 863	case SCSI_PROTOCOL_SAS:
 864		return "SAS";
 865	case SCSI_PROTOCOL_FCP:
 866		return "FCP";
 867	case SCSI_PROTOCOL_ISCSI:
 868		return "iSCSI";
 869	default:
 870		break;
 871	}
 872
 873	return "Unknown";
 874}
 875
 876/* Start items for tcm_loop_port_cit */
 877
 878static int tcm_loop_port_link(
 879	struct se_portal_group *se_tpg,
 880	struct se_lun *lun)
 881{
 882	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
 883				struct tcm_loop_tpg, tl_se_tpg);
 884	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 885
 886	atomic_inc(&tl_tpg->tl_tpg_port_count);
 887	smp_mb__after_atomic_inc();
 888	/*
 889	 * Add Linux/SCSI struct scsi_device by HCTL
 890	 */
 891	scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
 892
 893	pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
 894	return 0;
 895}
 896
 897static void tcm_loop_port_unlink(
 898	struct se_portal_group *se_tpg,
 899	struct se_lun *se_lun)
 900{
 901	struct scsi_device *sd;
 902	struct tcm_loop_hba *tl_hba;
 903	struct tcm_loop_tpg *tl_tpg;
 904
 905	tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
 906	tl_hba = tl_tpg->tl_hba;
 907
 908	sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
 909				se_lun->unpacked_lun);
 910	if (!sd) {
 911		pr_err("Unable to locate struct scsi_device for %d:%d:"
 912			"%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
 913		return;
 914	}
 915	/*
 916	 * Remove Linux/SCSI struct scsi_device by HCTL
 917	 */
 918	scsi_remove_device(sd);
 919	scsi_device_put(sd);
 920
 921	atomic_dec(&tl_tpg->tl_tpg_port_count);
 922	smp_mb__after_atomic_dec();
 923
 924	pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
 925}
 926
 927/* End items for tcm_loop_port_cit */
 928
 929/* Start items for tcm_loop_nexus_cit */
 930
 931static int tcm_loop_make_nexus(
 932	struct tcm_loop_tpg *tl_tpg,
 933	const char *name)
 934{
 935	struct se_portal_group *se_tpg;
 936	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
 937	struct tcm_loop_nexus *tl_nexus;
 938	int ret = -ENOMEM;
 939
 940	if (tl_tpg->tl_hba->tl_nexus) {
 941		pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
 942		return -EEXIST;
 943	}
 944	se_tpg = &tl_tpg->tl_se_tpg;
 945
 946	tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
 947	if (!tl_nexus) {
 948		pr_err("Unable to allocate struct tcm_loop_nexus\n");
 949		return -ENOMEM;
 950	}
 951	/*
 952	 * Initialize the struct se_session pointer
 953	 */
 954	tl_nexus->se_sess = transport_init_session();
 955	if (IS_ERR(tl_nexus->se_sess)) {
 956		ret = PTR_ERR(tl_nexus->se_sess);
 957		goto out;
 958	}
 959	/*
 960	 * Since we are running in 'demo mode' this call with generate a
 961	 * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
 962	 * Initiator port name of the passed configfs group 'name'.
 963	 */
 964	tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 965				se_tpg, (unsigned char *)name);
 966	if (!tl_nexus->se_sess->se_node_acl) {
 967		transport_free_session(tl_nexus->se_sess);
 968		goto out;
 969	}
 970	/*
 971	 * Now, register the SAS I_T Nexus as active with the call to
 972	 * transport_register_session()
 973	 */
 974	__transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
 975			tl_nexus->se_sess, tl_nexus);
 976	tl_tpg->tl_hba->tl_nexus = tl_nexus;
 977	pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
 978		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
 979		name);
 980	return 0;
 981
 982out:
 983	kfree(tl_nexus);
 984	return ret;
 985}
 986
 987static int tcm_loop_drop_nexus(
 988	struct tcm_loop_tpg *tpg)
 989{
 990	struct se_session *se_sess;
 991	struct tcm_loop_nexus *tl_nexus;
 992	struct tcm_loop_hba *tl_hba = tpg->tl_hba;
 993
 994	tl_nexus = tpg->tl_hba->tl_nexus;
 995	if (!tl_nexus)
 996		return -ENODEV;
 997
 998	se_sess = tl_nexus->se_sess;
 999	if (!se_sess)
1000		return -ENODEV;
1001
1002	if (atomic_read(&tpg->tl_tpg_port_count)) {
1003		pr_err("Unable to remove TCM_Loop I_T Nexus with"
1004			" active TPG port count: %d\n",
1005			atomic_read(&tpg->tl_tpg_port_count));
1006		return -EPERM;
1007	}
1008
1009	pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1010		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1011		tl_nexus->se_sess->se_node_acl->initiatorname);
1012	/*
1013	 * Release the SCSI I_T Nexus to the emulated SAS Target Port
1014	 */
1015	transport_deregister_session(tl_nexus->se_sess);
1016	tpg->tl_hba->tl_nexus = NULL;
1017	kfree(tl_nexus);
1018	return 0;
1019}
1020
1021/* End items for tcm_loop_nexus_cit */
1022
1023static ssize_t tcm_loop_tpg_show_nexus(
1024	struct se_portal_group *se_tpg,
1025	char *page)
1026{
1027	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1028			struct tcm_loop_tpg, tl_se_tpg);
1029	struct tcm_loop_nexus *tl_nexus;
1030	ssize_t ret;
1031
1032	tl_nexus = tl_tpg->tl_hba->tl_nexus;
1033	if (!tl_nexus)
1034		return -ENODEV;
1035
1036	ret = snprintf(page, PAGE_SIZE, "%s\n",
1037		tl_nexus->se_sess->se_node_acl->initiatorname);
1038
1039	return ret;
1040}
1041
1042static ssize_t tcm_loop_tpg_store_nexus(
1043	struct se_portal_group *se_tpg,
1044	const char *page,
1045	size_t count)
1046{
1047	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1048			struct tcm_loop_tpg, tl_se_tpg);
1049	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1050	unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1051	int ret;
1052	/*
1053	 * Shutdown the active I_T nexus if 'NULL' is passed..
1054	 */
1055	if (!strncmp(page, "NULL", 4)) {
1056		ret = tcm_loop_drop_nexus(tl_tpg);
1057		return (!ret) ? count : ret;
1058	}
1059	/*
1060	 * Otherwise make sure the passed virtual Initiator port WWN matches
1061	 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1062	 * tcm_loop_make_nexus()
1063	 */
1064	if (strlen(page) >= TL_WWN_ADDR_LEN) {
1065		pr_err("Emulated NAA Sas Address: %s, exceeds"
1066				" max: %d\n", page, TL_WWN_ADDR_LEN);
1067		return -EINVAL;
1068	}
1069	snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1070
1071	ptr = strstr(i_port, "naa.");
1072	if (ptr) {
1073		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1074			pr_err("Passed SAS Initiator Port %s does not"
1075				" match target port protoid: %s\n", i_port,
1076				tcm_loop_dump_proto_id(tl_hba));
1077			return -EINVAL;
1078		}
1079		port_ptr = &i_port[0];
1080		goto check_newline;
1081	}
1082	ptr = strstr(i_port, "fc.");
1083	if (ptr) {
1084		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1085			pr_err("Passed FCP Initiator Port %s does not"
1086				" match target port protoid: %s\n", i_port,
1087				tcm_loop_dump_proto_id(tl_hba));
1088			return -EINVAL;
1089		}
1090		port_ptr = &i_port[3]; /* Skip over "fc." */
1091		goto check_newline;
1092	}
1093	ptr = strstr(i_port, "iqn.");
1094	if (ptr) {
1095		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1096			pr_err("Passed iSCSI Initiator Port %s does not"
1097				" match target port protoid: %s\n", i_port,
1098				tcm_loop_dump_proto_id(tl_hba));
1099			return -EINVAL;
1100		}
1101		port_ptr = &i_port[0];
1102		goto check_newline;
1103	}
1104	pr_err("Unable to locate prefix for emulated Initiator Port:"
1105			" %s\n", i_port);
1106	return -EINVAL;
1107	/*
1108	 * Clear any trailing newline for the NAA WWN
1109	 */
1110check_newline:
1111	if (i_port[strlen(i_port)-1] == '\n')
1112		i_port[strlen(i_port)-1] = '\0';
1113
1114	ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1115	if (ret < 0)
1116		return ret;
1117
1118	return count;
1119}
1120
1121TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1122
1123static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1124	&tcm_loop_tpg_nexus.attr,
1125	NULL,
1126};
1127
1128/* Start items for tcm_loop_naa_cit */
1129
1130struct se_portal_group *tcm_loop_make_naa_tpg(
1131	struct se_wwn *wwn,
1132	struct config_group *group,
1133	const char *name)
1134{
1135	struct tcm_loop_hba *tl_hba = container_of(wwn,
1136			struct tcm_loop_hba, tl_hba_wwn);
1137	struct tcm_loop_tpg *tl_tpg;
1138	char *tpgt_str, *end_ptr;
1139	int ret;
1140	unsigned short int tpgt;
1141
1142	tpgt_str = strstr(name, "tpgt_");
1143	if (!tpgt_str) {
1144		pr_err("Unable to locate \"tpgt_#\" directory"
1145				" group\n");
1146		return ERR_PTR(-EINVAL);
1147	}
1148	tpgt_str += 5; /* Skip ahead of "tpgt_" */
1149	tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1150
1151	if (tpgt >= TL_TPGS_PER_HBA) {
1152		pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1153				" %u\n", tpgt, TL_TPGS_PER_HBA);
1154		return ERR_PTR(-EINVAL);
1155	}
1156	tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1157	tl_tpg->tl_hba = tl_hba;
1158	tl_tpg->tl_tpgt = tpgt;
1159	/*
1160	 * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1161	 */
1162	ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1163			wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1164			TRANSPORT_TPG_TYPE_NORMAL);
1165	if (ret < 0)
1166		return ERR_PTR(-ENOMEM);
1167
1168	pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1169		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1170		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1171
1172	return &tl_tpg->tl_se_tpg;
1173}
1174
1175void tcm_loop_drop_naa_tpg(
1176	struct se_portal_group *se_tpg)
1177{
1178	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1179	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1180				struct tcm_loop_tpg, tl_se_tpg);
1181	struct tcm_loop_hba *tl_hba;
1182	unsigned short tpgt;
1183
1184	tl_hba = tl_tpg->tl_hba;
1185	tpgt = tl_tpg->tl_tpgt;
1186	/*
1187	 * Release the I_T Nexus for the Virtual SAS link if present
1188	 */
1189	tcm_loop_drop_nexus(tl_tpg);
1190	/*
1191	 * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1192	 */
1193	core_tpg_deregister(se_tpg);
1194
1195	tl_tpg->tl_hba = NULL;
1196	tl_tpg->tl_tpgt = 0;
1197
1198	pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1199		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1200		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1201}
1202
1203/* End items for tcm_loop_naa_cit */
1204
1205/* Start items for tcm_loop_cit */
1206
1207struct se_wwn *tcm_loop_make_scsi_hba(
1208	struct target_fabric_configfs *tf,
1209	struct config_group *group,
1210	const char *name)
1211{
1212	struct tcm_loop_hba *tl_hba;
1213	struct Scsi_Host *sh;
1214	char *ptr;
1215	int ret, off = 0;
1216
1217	tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1218	if (!tl_hba) {
1219		pr_err("Unable to allocate struct tcm_loop_hba\n");
1220		return ERR_PTR(-ENOMEM);
1221	}
1222	/*
1223	 * Determine the emulated Protocol Identifier and Target Port Name
1224	 * based on the incoming configfs directory name.
1225	 */
1226	ptr = strstr(name, "naa.");
1227	if (ptr) {
1228		tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1229		goto check_len;
1230	}
1231	ptr = strstr(name, "fc.");
1232	if (ptr) {
1233		tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1234		off = 3; /* Skip over "fc." */
1235		goto check_len;
1236	}
1237	ptr = strstr(name, "iqn.");
1238	if (!ptr) {
1239		pr_err("Unable to locate prefix for emulated Target "
1240				"Port: %s\n", name);
1241		ret = -EINVAL;
1242		goto out;
1243	}
1244	tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1245
1246check_len:
1247	if (strlen(name) >= TL_WWN_ADDR_LEN) {
1248		pr_err("Emulated NAA %s Address: %s, exceeds"
1249			" max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1250			TL_WWN_ADDR_LEN);
1251		ret = -EINVAL;
1252		goto out;
1253	}
1254	snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1255
1256	/*
1257	 * Call device_register(tl_hba->dev) to register the emulated
1258	 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1259	 * device_register() callbacks in tcm_loop_driver_probe()
1260	 */
1261	ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1262	if (ret)
1263		goto out;
1264
1265	sh = tl_hba->sh;
1266	tcm_loop_hba_no_cnt++;
1267	pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1268		" %s Address: %s at Linux/SCSI Host ID: %d\n",
1269		tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1270
1271	return &tl_hba->tl_hba_wwn;
1272out:
1273	kfree(tl_hba);
1274	return ERR_PTR(ret);
1275}
1276
1277void tcm_loop_drop_scsi_hba(
1278	struct se_wwn *wwn)
1279{
1280	struct tcm_loop_hba *tl_hba = container_of(wwn,
1281				struct tcm_loop_hba, tl_hba_wwn);
1282
1283	pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1284		" SAS Address: %s at Linux/SCSI Host ID: %d\n",
1285		tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1286	/*
1287	 * Call device_unregister() on the original tl_hba->dev.
1288	 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1289	 * release *tl_hba;
1290	 */
1291	device_unregister(&tl_hba->dev);
 
 
 
 
1292}
1293
1294/* Start items for tcm_loop_cit */
1295static ssize_t tcm_loop_wwn_show_attr_version(
1296	struct target_fabric_configfs *tf,
1297	char *page)
1298{
1299	return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1300}
1301
1302TF_WWN_ATTR_RO(tcm_loop, version);
1303
1304static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1305	&tcm_loop_wwn_version.attr,
1306	NULL,
1307};
1308
1309/* End items for tcm_loop_cit */
1310
1311static int tcm_loop_register_configfs(void)
1312{
1313	struct target_fabric_configfs *fabric;
 
1314	int ret;
1315	/*
1316	 * Set the TCM Loop HBA counter to zero
1317	 */
1318	tcm_loop_hba_no_cnt = 0;
1319	/*
1320	 * Register the top level struct config_item_type with TCM core
1321	 */
1322	fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1323	if (IS_ERR(fabric)) {
1324		pr_err("tcm_loop_register_configfs() failed!\n");
1325		return PTR_ERR(fabric);
1326	}
1327	/*
1328	 * Setup the fabric API of function pointers used by target_core_mod
1329	 */
1330	fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1331	fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1332	fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1333	fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1334	fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1335	fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1336	fabric->tf_ops.tpg_get_pr_transport_id_len =
1337					&tcm_loop_get_pr_transport_id_len;
1338	fabric->tf_ops.tpg_parse_pr_out_transport_id =
1339					&tcm_loop_parse_pr_out_transport_id;
1340	fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1341	fabric->tf_ops.tpg_check_demo_mode_cache =
1342					&tcm_loop_check_demo_mode_cache;
1343	fabric->tf_ops.tpg_check_demo_mode_write_protect =
1344					&tcm_loop_check_demo_mode_write_protect;
1345	fabric->tf_ops.tpg_check_prod_mode_write_protect =
1346					&tcm_loop_check_prod_mode_write_protect;
1347	/*
1348	 * The TCM loopback fabric module runs in demo-mode to a local
1349	 * virtual SCSI device, so fabric dependent initator ACLs are
1350	 * not required.
1351	 */
1352	fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1353	fabric->tf_ops.tpg_release_fabric_acl =
1354					&tcm_loop_tpg_release_fabric_acl;
1355	fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1356	/*
1357	 * Used for setting up remaining TCM resources in process context
1358	 */
 
1359	fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1360	fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1361	fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1362	fabric->tf_ops.close_session = &tcm_loop_close_session;
 
 
 
1363	fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1364	fabric->tf_ops.sess_get_initiator_sid = NULL;
1365	fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1366	fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1367	/*
1368	 * Not used for TCM loopback
1369	 */
1370	fabric->tf_ops.set_default_node_attributes =
1371					&tcm_loop_set_default_node_attributes;
1372	fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1373	fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1374	fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1375	fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1376	fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1377	fabric->tf_ops.set_fabric_sense_len = &tcm_loop_set_fabric_sense_len;
1378	fabric->tf_ops.get_fabric_sense_len = &tcm_loop_get_fabric_sense_len;
 
1379
 
1380	/*
1381	 * Setup function pointers for generic logic in target_core_fabric_configfs.c
1382	 */
1383	fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1384	fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1385	fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1386	fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1387	/*
1388	 * fabric_post_link() and fabric_pre_unlink() are used for
1389	 * registration and release of TCM Loop Virtual SCSI LUNs.
1390	 */
1391	fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1392	fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1393	fabric->tf_ops.fabric_make_np = NULL;
1394	fabric->tf_ops.fabric_drop_np = NULL;
1395	/*
1396	 * Setup default attribute lists for various fabric->tf_cit_tmpl
1397	 */
1398	TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1399	TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1400	TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1401	TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1402	TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1403	/*
1404	 * Once fabric->tf_ops has been setup, now register the fabric for
1405	 * use within TCM
1406	 */
1407	ret = target_fabric_configfs_register(fabric);
1408	if (ret < 0) {
1409		pr_err("target_fabric_configfs_register() for"
1410				" TCM_Loop failed!\n");
1411		target_fabric_configfs_free(fabric);
1412		return -1;
1413	}
1414	/*
1415	 * Setup our local pointer to *fabric.
1416	 */
1417	tcm_loop_fabric_configfs = fabric;
1418	pr_debug("TCM_LOOP[0] - Set fabric ->"
1419			" tcm_loop_fabric_configfs\n");
1420	return 0;
1421}
1422
1423static void tcm_loop_deregister_configfs(void)
1424{
1425	if (!tcm_loop_fabric_configfs)
1426		return;
1427
1428	target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1429	tcm_loop_fabric_configfs = NULL;
1430	pr_debug("TCM_LOOP[0] - Cleared"
1431				" tcm_loop_fabric_configfs\n");
1432}
1433
1434static int __init tcm_loop_fabric_init(void)
1435{
1436	int ret = -ENOMEM;
1437
1438	tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1439	if (!tcm_loop_workqueue)
1440		goto out;
1441
1442	tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1443				sizeof(struct tcm_loop_cmd),
1444				__alignof__(struct tcm_loop_cmd),
1445				0, NULL);
1446	if (!tcm_loop_cmd_cache) {
1447		pr_debug("kmem_cache_create() for"
1448			" tcm_loop_cmd_cache failed\n");
1449		goto out_destroy_workqueue;
1450	}
1451
1452	ret = tcm_loop_alloc_core_bus();
1453	if (ret)
1454		goto out_destroy_cache;
1455
1456	ret = tcm_loop_register_configfs();
1457	if (ret)
1458		goto out_release_core_bus;
 
 
1459
1460	return 0;
1461
1462out_release_core_bus:
1463	tcm_loop_release_core_bus();
1464out_destroy_cache:
1465	kmem_cache_destroy(tcm_loop_cmd_cache);
1466out_destroy_workqueue:
1467	destroy_workqueue(tcm_loop_workqueue);
1468out:
1469	return ret;
1470}
1471
1472static void __exit tcm_loop_fabric_exit(void)
1473{
1474	tcm_loop_deregister_configfs();
1475	tcm_loop_release_core_bus();
1476	kmem_cache_destroy(tcm_loop_cmd_cache);
1477	destroy_workqueue(tcm_loop_workqueue);
1478}
1479
1480MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1481MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1482MODULE_LICENSE("GPL");
1483module_init(tcm_loop_fabric_init);
1484module_exit(tcm_loop_fabric_exit);