xref: /linux/drivers/target/loopback/tcm_loop.c (revision 517982229f78b2aebf00a8a337e84e8eeea70b8e)
1 /*******************************************************************************
2  *
3  * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
4  * for emulated SAS initiator ports
5  *
6  * © Copyright 2011-2013 Datera, Inc.
7  *
8  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
9  *
10  * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  ****************************************************************************/
22 
23 #include <linux/module.h>
24 #include <linux/moduleparam.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/types.h>
28 #include <linux/configfs.h>
29 #include <scsi/scsi.h>
30 #include <scsi/scsi_tcq.h>
31 #include <scsi/scsi_host.h>
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_cmnd.h>
34 
35 #include <target/target_core_base.h>
36 #include <target/target_core_fabric.h>
37 
38 #include "tcm_loop.h"
39 
40 #define to_tcm_loop_hba(hba)	container_of(hba, struct tcm_loop_hba, dev)
41 
42 static struct workqueue_struct *tcm_loop_workqueue;
43 static struct kmem_cache *tcm_loop_cmd_cache;
44 
45 static int tcm_loop_hba_no_cnt;
46 
47 static int tcm_loop_queue_status(struct se_cmd *se_cmd);
48 
49 /*
50  * Called from struct target_core_fabric_ops->check_stop_free()
51  */
52 static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
53 {
54 	/*
55 	 * Do not release struct se_cmd's containing a valid TMR
56 	 * pointer.  These will be released directly in tcm_loop_device_reset()
57 	 * with transport_generic_free_cmd().
58 	 */
59 	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
60 		return 0;
61 	/*
62 	 * Release the struct se_cmd, which will make a callback to release
63 	 * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
64 	 */
65 	transport_generic_free_cmd(se_cmd, 0);
66 	return 1;
67 }
68 
69 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
70 {
71 	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
72 				struct tcm_loop_cmd, tl_se_cmd);
73 
74 	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
75 }
76 
77 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
78 {
79 	seq_printf(m, "tcm_loop_proc_info()\n");
80 	return 0;
81 }
82 
83 static int tcm_loop_driver_probe(struct device *);
84 static int tcm_loop_driver_remove(struct device *);
85 
86 static int pseudo_lld_bus_match(struct device *dev,
87 				struct device_driver *dev_driver)
88 {
89 	return 1;
90 }
91 
92 static struct bus_type tcm_loop_lld_bus = {
93 	.name			= "tcm_loop_bus",
94 	.match			= pseudo_lld_bus_match,
95 	.probe			= tcm_loop_driver_probe,
96 	.remove			= tcm_loop_driver_remove,
97 };
98 
99 static struct device_driver tcm_loop_driverfs = {
100 	.name			= "tcm_loop",
101 	.bus			= &tcm_loop_lld_bus,
102 };
103 /*
104  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
105  */
106 static struct device *tcm_loop_primary;
107 
108 static void tcm_loop_submission_work(struct work_struct *work)
109 {
110 	struct tcm_loop_cmd *tl_cmd =
111 		container_of(work, struct tcm_loop_cmd, work);
112 	struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
113 	struct scsi_cmnd *sc = tl_cmd->sc;
114 	struct tcm_loop_nexus *tl_nexus;
115 	struct tcm_loop_hba *tl_hba;
116 	struct tcm_loop_tpg *tl_tpg;
117 	struct scatterlist *sgl_bidi = NULL;
118 	u32 sgl_bidi_count = 0, transfer_length;
119 	int rc;
120 
121 	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
122 	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
123 
124 	/*
125 	 * Ensure that this tl_tpg reference from the incoming sc->device->id
126 	 * has already been configured via tcm_loop_make_naa_tpg().
127 	 */
128 	if (!tl_tpg->tl_hba) {
129 		set_host_byte(sc, DID_NO_CONNECT);
130 		goto out_done;
131 	}
132 	if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
133 		set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
134 		goto out_done;
135 	}
136 	tl_nexus = tl_tpg->tl_nexus;
137 	if (!tl_nexus) {
138 		scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
139 				" does not exist\n");
140 		set_host_byte(sc, DID_ERROR);
141 		goto out_done;
142 	}
143 	if (scsi_bidi_cmnd(sc)) {
144 		struct scsi_data_buffer *sdb = scsi_in(sc);
145 
146 		sgl_bidi = sdb->table.sgl;
147 		sgl_bidi_count = sdb->table.nents;
148 		se_cmd->se_cmd_flags |= SCF_BIDI;
149 
150 	}
151 
152 	transfer_length = scsi_transfer_length(sc);
153 	if (!scsi_prot_sg_count(sc) &&
154 	    scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
155 		se_cmd->prot_pto = true;
156 		/*
157 		 * loopback transport doesn't support
158 		 * WRITE_GENERATE, READ_STRIP protection
159 		 * information operations, go ahead unprotected.
160 		 */
161 		transfer_length = scsi_bufflen(sc);
162 	}
163 
164 	se_cmd->tag = tl_cmd->sc_cmd_tag;
165 	rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
166 			&tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
167 			transfer_length, TCM_SIMPLE_TAG,
168 			sc->sc_data_direction, 0,
169 			scsi_sglist(sc), scsi_sg_count(sc),
170 			sgl_bidi, sgl_bidi_count,
171 			scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
172 	if (rc < 0) {
173 		set_host_byte(sc, DID_NO_CONNECT);
174 		goto out_done;
175 	}
176 	return;
177 
178 out_done:
179 	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
180 	sc->scsi_done(sc);
181 	return;
182 }
183 
184 /*
185  * ->queuecommand can be and usually is called from interrupt context, so
186  * defer the actual submission to a workqueue.
187  */
188 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
189 {
190 	struct tcm_loop_cmd *tl_cmd;
191 
192 	pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
193 		" scsi_buf_len: %u\n", sc->device->host->host_no,
194 		sc->device->id, sc->device->channel, sc->device->lun,
195 		sc->cmnd[0], scsi_bufflen(sc));
196 
197 	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
198 	if (!tl_cmd) {
199 		pr_err("Unable to allocate struct tcm_loop_cmd\n");
200 		set_host_byte(sc, DID_ERROR);
201 		sc->scsi_done(sc);
202 		return 0;
203 	}
204 
205 	tl_cmd->sc = sc;
206 	tl_cmd->sc_cmd_tag = sc->request->tag;
207 	INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
208 	queue_work(tcm_loop_workqueue, &tl_cmd->work);
209 	return 0;
210 }
211 
212 /*
213  * Called from SCSI EH process context to issue a LUN_RESET TMR
214  * to struct scsi_device
215  */
216 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
217 			      u64 lun, int task, enum tcm_tmreq_table tmr)
218 {
219 	struct se_cmd *se_cmd = NULL;
220 	struct se_session *se_sess;
221 	struct se_portal_group *se_tpg;
222 	struct tcm_loop_nexus *tl_nexus;
223 	struct tcm_loop_cmd *tl_cmd = NULL;
224 	struct tcm_loop_tmr *tl_tmr = NULL;
225 	int ret = TMR_FUNCTION_FAILED, rc;
226 
227 	/*
228 	 * Locate the tl_nexus and se_sess pointers
229 	 */
230 	tl_nexus = tl_tpg->tl_nexus;
231 	if (!tl_nexus) {
232 		pr_err("Unable to perform device reset without"
233 				" active I_T Nexus\n");
234 		return ret;
235 	}
236 
237 	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
238 	if (!tl_cmd) {
239 		pr_err("Unable to allocate memory for tl_cmd\n");
240 		return ret;
241 	}
242 
243 	tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
244 	if (!tl_tmr) {
245 		pr_err("Unable to allocate memory for tl_tmr\n");
246 		goto release;
247 	}
248 	init_waitqueue_head(&tl_tmr->tl_tmr_wait);
249 
250 	se_cmd = &tl_cmd->tl_se_cmd;
251 	se_tpg = &tl_tpg->tl_se_tpg;
252 	se_sess = tl_tpg->tl_nexus->se_sess;
253 	/*
254 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
255 	 */
256 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
257 				DMA_NONE, TCM_SIMPLE_TAG,
258 				&tl_cmd->tl_sense_buf[0]);
259 
260 	rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
261 	if (rc < 0)
262 		goto release;
263 
264 	if (tmr == TMR_ABORT_TASK)
265 		se_cmd->se_tmr_req->ref_task_tag = task;
266 
267 	/*
268 	 * Locate the underlying TCM struct se_lun
269 	 */
270 	if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
271 		ret = TMR_LUN_DOES_NOT_EXIST;
272 		goto release;
273 	}
274 	/*
275 	 * Queue the TMR to TCM Core and sleep waiting for
276 	 * tcm_loop_queue_tm_rsp() to wake us up.
277 	 */
278 	transport_generic_handle_tmr(se_cmd);
279 	wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
280 	/*
281 	 * The TMR LUN_RESET has completed, check the response status and
282 	 * then release allocations.
283 	 */
284 	ret = se_cmd->se_tmr_req->response;
285 release:
286 	if (se_cmd)
287 		transport_generic_free_cmd(se_cmd, 1);
288 	else
289 		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
290 	kfree(tl_tmr);
291 	return ret;
292 }
293 
294 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
295 {
296 	struct tcm_loop_hba *tl_hba;
297 	struct tcm_loop_tpg *tl_tpg;
298 	int ret = FAILED;
299 
300 	/*
301 	 * Locate the tcm_loop_hba_t pointer
302 	 */
303 	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
304 	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
305 	ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
306 				 sc->request->tag, TMR_ABORT_TASK);
307 	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
308 }
309 
310 /*
311  * Called from SCSI EH process context to issue a LUN_RESET TMR
312  * to struct scsi_device
313  */
314 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
315 {
316 	struct tcm_loop_hba *tl_hba;
317 	struct tcm_loop_tpg *tl_tpg;
318 	int ret = FAILED;
319 
320 	/*
321 	 * Locate the tcm_loop_hba_t pointer
322 	 */
323 	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
324 	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
325 
326 	ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
327 				 0, TMR_LUN_RESET);
328 	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
329 }
330 
331 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
332 {
333 	struct tcm_loop_hba *tl_hba;
334 	struct tcm_loop_tpg *tl_tpg;
335 
336 	/*
337 	 * Locate the tcm_loop_hba_t pointer
338 	 */
339 	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
340 	if (!tl_hba) {
341 		pr_err("Unable to perform device reset without"
342 				" active I_T Nexus\n");
343 		return FAILED;
344 	}
345 	/*
346 	 * Locate the tl_tpg pointer from TargetID in sc->device->id
347 	 */
348 	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
349 	if (tl_tpg) {
350 		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
351 		return SUCCESS;
352 	}
353 	return FAILED;
354 }
355 
356 static int tcm_loop_slave_alloc(struct scsi_device *sd)
357 {
358 	set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
359 	return 0;
360 }
361 
362 static struct scsi_host_template tcm_loop_driver_template = {
363 	.show_info		= tcm_loop_show_info,
364 	.proc_name		= "tcm_loopback",
365 	.name			= "TCM_Loopback",
366 	.queuecommand		= tcm_loop_queuecommand,
367 	.change_queue_depth	= scsi_change_queue_depth,
368 	.eh_abort_handler = tcm_loop_abort_task,
369 	.eh_device_reset_handler = tcm_loop_device_reset,
370 	.eh_target_reset_handler = tcm_loop_target_reset,
371 	.can_queue		= 1024,
372 	.this_id		= -1,
373 	.sg_tablesize		= 256,
374 	.cmd_per_lun		= 1024,
375 	.max_sectors		= 0xFFFF,
376 	.use_clustering		= DISABLE_CLUSTERING,
377 	.slave_alloc		= tcm_loop_slave_alloc,
378 	.module			= THIS_MODULE,
379 	.use_blk_tags		= 1,
380 	.track_queue_depth	= 1,
381 };
382 
383 static int tcm_loop_driver_probe(struct device *dev)
384 {
385 	struct tcm_loop_hba *tl_hba;
386 	struct Scsi_Host *sh;
387 	int error, host_prot;
388 
389 	tl_hba = to_tcm_loop_hba(dev);
390 
391 	sh = scsi_host_alloc(&tcm_loop_driver_template,
392 			sizeof(struct tcm_loop_hba));
393 	if (!sh) {
394 		pr_err("Unable to allocate struct scsi_host\n");
395 		return -ENODEV;
396 	}
397 	tl_hba->sh = sh;
398 
399 	/*
400 	 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
401 	 */
402 	*((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
403 	/*
404 	 * Setup single ID, Channel and LUN for now..
405 	 */
406 	sh->max_id = 2;
407 	sh->max_lun = 0;
408 	sh->max_channel = 0;
409 	sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
410 
411 	host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
412 		    SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
413 		    SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
414 
415 	scsi_host_set_prot(sh, host_prot);
416 	scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
417 
418 	error = scsi_add_host(sh, &tl_hba->dev);
419 	if (error) {
420 		pr_err("%s: scsi_add_host failed\n", __func__);
421 		scsi_host_put(sh);
422 		return -ENODEV;
423 	}
424 	return 0;
425 }
426 
427 static int tcm_loop_driver_remove(struct device *dev)
428 {
429 	struct tcm_loop_hba *tl_hba;
430 	struct Scsi_Host *sh;
431 
432 	tl_hba = to_tcm_loop_hba(dev);
433 	sh = tl_hba->sh;
434 
435 	scsi_remove_host(sh);
436 	scsi_host_put(sh);
437 	return 0;
438 }
439 
440 static void tcm_loop_release_adapter(struct device *dev)
441 {
442 	struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
443 
444 	kfree(tl_hba);
445 }
446 
447 /*
448  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
449  */
450 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
451 {
452 	int ret;
453 
454 	tl_hba->dev.bus = &tcm_loop_lld_bus;
455 	tl_hba->dev.parent = tcm_loop_primary;
456 	tl_hba->dev.release = &tcm_loop_release_adapter;
457 	dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
458 
459 	ret = device_register(&tl_hba->dev);
460 	if (ret) {
461 		pr_err("device_register() failed for"
462 				" tl_hba->dev: %d\n", ret);
463 		return -ENODEV;
464 	}
465 
466 	return 0;
467 }
468 
469 /*
470  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
471  * tcm_loop SCSI bus.
472  */
473 static int tcm_loop_alloc_core_bus(void)
474 {
475 	int ret;
476 
477 	tcm_loop_primary = root_device_register("tcm_loop_0");
478 	if (IS_ERR(tcm_loop_primary)) {
479 		pr_err("Unable to allocate tcm_loop_primary\n");
480 		return PTR_ERR(tcm_loop_primary);
481 	}
482 
483 	ret = bus_register(&tcm_loop_lld_bus);
484 	if (ret) {
485 		pr_err("bus_register() failed for tcm_loop_lld_bus\n");
486 		goto dev_unreg;
487 	}
488 
489 	ret = driver_register(&tcm_loop_driverfs);
490 	if (ret) {
491 		pr_err("driver_register() failed for"
492 				"tcm_loop_driverfs\n");
493 		goto bus_unreg;
494 	}
495 
496 	pr_debug("Initialized TCM Loop Core Bus\n");
497 	return ret;
498 
499 bus_unreg:
500 	bus_unregister(&tcm_loop_lld_bus);
501 dev_unreg:
502 	root_device_unregister(tcm_loop_primary);
503 	return ret;
504 }
505 
506 static void tcm_loop_release_core_bus(void)
507 {
508 	driver_unregister(&tcm_loop_driverfs);
509 	bus_unregister(&tcm_loop_lld_bus);
510 	root_device_unregister(tcm_loop_primary);
511 
512 	pr_debug("Releasing TCM Loop Core BUS\n");
513 }
514 
515 static char *tcm_loop_get_fabric_name(void)
516 {
517 	return "loopback";
518 }
519 
520 static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
521 {
522 	return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
523 }
524 
525 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
526 {
527 	/*
528 	 * Return the passed NAA identifier for the Target Port
529 	 */
530 	return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
531 }
532 
533 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
534 {
535 	/*
536 	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
537 	 * to represent the SCSI Target Port.
538 	 */
539 	return tl_tpg(se_tpg)->tl_tpgt;
540 }
541 
542 /*
543  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
544  * based upon the incoming fabric dependent SCSI Initiator Port
545  */
546 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
547 {
548 	return 1;
549 }
550 
551 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
552 {
553 	return 0;
554 }
555 
556 /*
557  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
558  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
559  */
560 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
561 {
562 	return 0;
563 }
564 
565 /*
566  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
567  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
568  * It has been added here as a nop for target_fabric_tf_ops_check()
569  */
570 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
571 {
572 	return 0;
573 }
574 
575 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
576 {
577 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
578 						   tl_se_tpg);
579 	return tl_tpg->tl_fabric_prot_type;
580 }
581 
582 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
583 {
584 	return 1;
585 }
586 
587 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
588 {
589 	return 1;
590 }
591 
592 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
593 {
594 	return;
595 }
596 
597 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
598 {
599 	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
600 			struct tcm_loop_cmd, tl_se_cmd);
601 
602 	return tl_cmd->sc_cmd_state;
603 }
604 
605 static int tcm_loop_shutdown_session(struct se_session *se_sess)
606 {
607 	return 0;
608 }
609 
610 static void tcm_loop_close_session(struct se_session *se_sess)
611 {
612 	return;
613 };
614 
615 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
616 {
617 	/*
618 	 * Since Linux/SCSI has already sent down a struct scsi_cmnd
619 	 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
620 	 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
621 	 * format with transport_generic_map_mem_to_cmd().
622 	 *
623 	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
624 	 * object execution queue.
625 	 */
626 	target_execute_cmd(se_cmd);
627 	return 0;
628 }
629 
630 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
631 {
632 	return 0;
633 }
634 
635 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
636 {
637 	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
638 				struct tcm_loop_cmd, tl_se_cmd);
639 	struct scsi_cmnd *sc = tl_cmd->sc;
640 
641 	pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
642 		     " cdb: 0x%02x\n", sc, sc->cmnd[0]);
643 
644 	sc->result = SAM_STAT_GOOD;
645 	set_host_byte(sc, DID_OK);
646 	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
647 	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
648 		scsi_set_resid(sc, se_cmd->residual_count);
649 	sc->scsi_done(sc);
650 	return 0;
651 }
652 
653 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
654 {
655 	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
656 				struct tcm_loop_cmd, tl_se_cmd);
657 	struct scsi_cmnd *sc = tl_cmd->sc;
658 
659 	pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
660 			" cdb: 0x%02x\n", sc, sc->cmnd[0]);
661 
662 	if (se_cmd->sense_buffer &&
663 	   ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
664 	    (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
665 
666 		memcpy(sc->sense_buffer, se_cmd->sense_buffer,
667 				SCSI_SENSE_BUFFERSIZE);
668 		sc->result = SAM_STAT_CHECK_CONDITION;
669 		set_driver_byte(sc, DRIVER_SENSE);
670 	} else
671 		sc->result = se_cmd->scsi_status;
672 
673 	set_host_byte(sc, DID_OK);
674 	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
675 	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
676 		scsi_set_resid(sc, se_cmd->residual_count);
677 	sc->scsi_done(sc);
678 	return 0;
679 }
680 
681 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
682 {
683 	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
684 	struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
685 	/*
686 	 * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
687 	 * and wake up the wait_queue_head_t in tcm_loop_device_reset()
688 	 */
689 	atomic_set(&tl_tmr->tmr_complete, 1);
690 	wake_up(&tl_tmr->tl_tmr_wait);
691 }
692 
693 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
694 {
695 	return;
696 }
697 
698 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
699 {
700 	switch (tl_hba->tl_proto_id) {
701 	case SCSI_PROTOCOL_SAS:
702 		return "SAS";
703 	case SCSI_PROTOCOL_FCP:
704 		return "FCP";
705 	case SCSI_PROTOCOL_ISCSI:
706 		return "iSCSI";
707 	default:
708 		break;
709 	}
710 
711 	return "Unknown";
712 }
713 
714 /* Start items for tcm_loop_port_cit */
715 
716 static int tcm_loop_port_link(
717 	struct se_portal_group *se_tpg,
718 	struct se_lun *lun)
719 {
720 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
721 				struct tcm_loop_tpg, tl_se_tpg);
722 	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
723 
724 	atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
725 	/*
726 	 * Add Linux/SCSI struct scsi_device by HCTL
727 	 */
728 	scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
729 
730 	pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
731 	return 0;
732 }
733 
734 static void tcm_loop_port_unlink(
735 	struct se_portal_group *se_tpg,
736 	struct se_lun *se_lun)
737 {
738 	struct scsi_device *sd;
739 	struct tcm_loop_hba *tl_hba;
740 	struct tcm_loop_tpg *tl_tpg;
741 
742 	tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
743 	tl_hba = tl_tpg->tl_hba;
744 
745 	sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
746 				se_lun->unpacked_lun);
747 	if (!sd) {
748 		pr_err("Unable to locate struct scsi_device for %d:%d:"
749 			"%llu\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
750 		return;
751 	}
752 	/*
753 	 * Remove Linux/SCSI struct scsi_device by HCTL
754 	 */
755 	scsi_remove_device(sd);
756 	scsi_device_put(sd);
757 
758 	atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
759 
760 	pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
761 }
762 
763 /* End items for tcm_loop_port_cit */
764 
765 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
766 		struct config_item *item, char *page)
767 {
768 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
769 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
770 						   tl_se_tpg);
771 
772 	return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
773 }
774 
775 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
776 		struct config_item *item, const char *page, size_t count)
777 {
778 	struct se_portal_group *se_tpg = attrib_to_tpg(item);
779 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
780 						   tl_se_tpg);
781 	unsigned long val;
782 	int ret = kstrtoul(page, 0, &val);
783 
784 	if (ret) {
785 		pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
786 		return ret;
787 	}
788 	if (val != 0 && val != 1 && val != 3) {
789 		pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
790 		return -EINVAL;
791 	}
792 	tl_tpg->tl_fabric_prot_type = val;
793 
794 	return count;
795 }
796 
797 CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
798 
799 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
800 	&tcm_loop_tpg_attrib_attr_fabric_prot_type,
801 	NULL,
802 };
803 
804 /* Start items for tcm_loop_nexus_cit */
805 
806 static int tcm_loop_make_nexus(
807 	struct tcm_loop_tpg *tl_tpg,
808 	const char *name)
809 {
810 	struct se_portal_group *se_tpg;
811 	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
812 	struct tcm_loop_nexus *tl_nexus;
813 	int ret = -ENOMEM;
814 
815 	if (tl_tpg->tl_nexus) {
816 		pr_debug("tl_tpg->tl_nexus already exists\n");
817 		return -EEXIST;
818 	}
819 	se_tpg = &tl_tpg->tl_se_tpg;
820 
821 	tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
822 	if (!tl_nexus) {
823 		pr_err("Unable to allocate struct tcm_loop_nexus\n");
824 		return -ENOMEM;
825 	}
826 	/*
827 	 * Initialize the struct se_session pointer
828 	 */
829 	tl_nexus->se_sess = transport_init_session(
830 				TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS);
831 	if (IS_ERR(tl_nexus->se_sess)) {
832 		ret = PTR_ERR(tl_nexus->se_sess);
833 		goto out;
834 	}
835 	/*
836 	 * Since we are running in 'demo mode' this call with generate a
837 	 * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
838 	 * Initiator port name of the passed configfs group 'name'.
839 	 */
840 	tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
841 				se_tpg, (unsigned char *)name);
842 	if (!tl_nexus->se_sess->se_node_acl) {
843 		transport_free_session(tl_nexus->se_sess);
844 		goto out;
845 	}
846 	/* Now, register the I_T Nexus as active. */
847 	transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
848 			tl_nexus->se_sess, tl_nexus);
849 	tl_tpg->tl_nexus = tl_nexus;
850 	pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
851 		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
852 		name);
853 	return 0;
854 
855 out:
856 	kfree(tl_nexus);
857 	return ret;
858 }
859 
860 static int tcm_loop_drop_nexus(
861 	struct tcm_loop_tpg *tpg)
862 {
863 	struct se_session *se_sess;
864 	struct tcm_loop_nexus *tl_nexus;
865 
866 	tl_nexus = tpg->tl_nexus;
867 	if (!tl_nexus)
868 		return -ENODEV;
869 
870 	se_sess = tl_nexus->se_sess;
871 	if (!se_sess)
872 		return -ENODEV;
873 
874 	if (atomic_read(&tpg->tl_tpg_port_count)) {
875 		pr_err("Unable to remove TCM_Loop I_T Nexus with"
876 			" active TPG port count: %d\n",
877 			atomic_read(&tpg->tl_tpg_port_count));
878 		return -EPERM;
879 	}
880 
881 	pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
882 		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
883 		tl_nexus->se_sess->se_node_acl->initiatorname);
884 	/*
885 	 * Release the SCSI I_T Nexus to the emulated Target Port
886 	 */
887 	transport_deregister_session(tl_nexus->se_sess);
888 	tpg->tl_nexus = NULL;
889 	kfree(tl_nexus);
890 	return 0;
891 }
892 
893 /* End items for tcm_loop_nexus_cit */
894 
895 static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
896 {
897 	struct se_portal_group *se_tpg = to_tpg(item);
898 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
899 			struct tcm_loop_tpg, tl_se_tpg);
900 	struct tcm_loop_nexus *tl_nexus;
901 	ssize_t ret;
902 
903 	tl_nexus = tl_tpg->tl_nexus;
904 	if (!tl_nexus)
905 		return -ENODEV;
906 
907 	ret = snprintf(page, PAGE_SIZE, "%s\n",
908 		tl_nexus->se_sess->se_node_acl->initiatorname);
909 
910 	return ret;
911 }
912 
913 static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
914 		const char *page, size_t count)
915 {
916 	struct se_portal_group *se_tpg = to_tpg(item);
917 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
918 			struct tcm_loop_tpg, tl_se_tpg);
919 	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
920 	unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
921 	int ret;
922 	/*
923 	 * Shutdown the active I_T nexus if 'NULL' is passed..
924 	 */
925 	if (!strncmp(page, "NULL", 4)) {
926 		ret = tcm_loop_drop_nexus(tl_tpg);
927 		return (!ret) ? count : ret;
928 	}
929 	/*
930 	 * Otherwise make sure the passed virtual Initiator port WWN matches
931 	 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
932 	 * tcm_loop_make_nexus()
933 	 */
934 	if (strlen(page) >= TL_WWN_ADDR_LEN) {
935 		pr_err("Emulated NAA Sas Address: %s, exceeds"
936 				" max: %d\n", page, TL_WWN_ADDR_LEN);
937 		return -EINVAL;
938 	}
939 	snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
940 
941 	ptr = strstr(i_port, "naa.");
942 	if (ptr) {
943 		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
944 			pr_err("Passed SAS Initiator Port %s does not"
945 				" match target port protoid: %s\n", i_port,
946 				tcm_loop_dump_proto_id(tl_hba));
947 			return -EINVAL;
948 		}
949 		port_ptr = &i_port[0];
950 		goto check_newline;
951 	}
952 	ptr = strstr(i_port, "fc.");
953 	if (ptr) {
954 		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
955 			pr_err("Passed FCP Initiator Port %s does not"
956 				" match target port protoid: %s\n", i_port,
957 				tcm_loop_dump_proto_id(tl_hba));
958 			return -EINVAL;
959 		}
960 		port_ptr = &i_port[3]; /* Skip over "fc." */
961 		goto check_newline;
962 	}
963 	ptr = strstr(i_port, "iqn.");
964 	if (ptr) {
965 		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
966 			pr_err("Passed iSCSI Initiator Port %s does not"
967 				" match target port protoid: %s\n", i_port,
968 				tcm_loop_dump_proto_id(tl_hba));
969 			return -EINVAL;
970 		}
971 		port_ptr = &i_port[0];
972 		goto check_newline;
973 	}
974 	pr_err("Unable to locate prefix for emulated Initiator Port:"
975 			" %s\n", i_port);
976 	return -EINVAL;
977 	/*
978 	 * Clear any trailing newline for the NAA WWN
979 	 */
980 check_newline:
981 	if (i_port[strlen(i_port)-1] == '\n')
982 		i_port[strlen(i_port)-1] = '\0';
983 
984 	ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
985 	if (ret < 0)
986 		return ret;
987 
988 	return count;
989 }
990 
991 static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
992 		char *page)
993 {
994 	struct se_portal_group *se_tpg = to_tpg(item);
995 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
996 			struct tcm_loop_tpg, tl_se_tpg);
997 	const char *status = NULL;
998 	ssize_t ret = -EINVAL;
999 
1000 	switch (tl_tpg->tl_transport_status) {
1001 	case TCM_TRANSPORT_ONLINE:
1002 		status = "online";
1003 		break;
1004 	case TCM_TRANSPORT_OFFLINE:
1005 		status = "offline";
1006 		break;
1007 	default:
1008 		break;
1009 	}
1010 
1011 	if (status)
1012 		ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1013 
1014 	return ret;
1015 }
1016 
1017 static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
1018 		const char *page, size_t count)
1019 {
1020 	struct se_portal_group *se_tpg = to_tpg(item);
1021 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1022 			struct tcm_loop_tpg, tl_se_tpg);
1023 
1024 	if (!strncmp(page, "online", 6)) {
1025 		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1026 		return count;
1027 	}
1028 	if (!strncmp(page, "offline", 7)) {
1029 		tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1030 		if (tl_tpg->tl_nexus) {
1031 			struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
1032 
1033 			core_allocate_nexus_loss_ua(tl_sess->se_node_acl);
1034 		}
1035 		return count;
1036 	}
1037 	return -EINVAL;
1038 }
1039 
1040 CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
1041 CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
1042 
1043 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1044 	&tcm_loop_tpg_attr_nexus,
1045 	&tcm_loop_tpg_attr_transport_status,
1046 	NULL,
1047 };
1048 
1049 /* Start items for tcm_loop_naa_cit */
1050 
1051 static struct se_portal_group *tcm_loop_make_naa_tpg(
1052 	struct se_wwn *wwn,
1053 	struct config_group *group,
1054 	const char *name)
1055 {
1056 	struct tcm_loop_hba *tl_hba = container_of(wwn,
1057 			struct tcm_loop_hba, tl_hba_wwn);
1058 	struct tcm_loop_tpg *tl_tpg;
1059 	int ret;
1060 	unsigned long tpgt;
1061 
1062 	if (strstr(name, "tpgt_") != name) {
1063 		pr_err("Unable to locate \"tpgt_#\" directory"
1064 				" group\n");
1065 		return ERR_PTR(-EINVAL);
1066 	}
1067 	if (kstrtoul(name+5, 10, &tpgt))
1068 		return ERR_PTR(-EINVAL);
1069 
1070 	if (tpgt >= TL_TPGS_PER_HBA) {
1071 		pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA:"
1072 				" %u\n", tpgt, TL_TPGS_PER_HBA);
1073 		return ERR_PTR(-EINVAL);
1074 	}
1075 	tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1076 	tl_tpg->tl_hba = tl_hba;
1077 	tl_tpg->tl_tpgt = tpgt;
1078 	/*
1079 	 * Register the tl_tpg as a emulated TCM Target Endpoint
1080 	 */
1081 	ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
1082 	if (ret < 0)
1083 		return ERR_PTR(-ENOMEM);
1084 
1085 	pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1086 		" Target Port %s,t,0x%04lx\n", tcm_loop_dump_proto_id(tl_hba),
1087 		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1088 
1089 	return &tl_tpg->tl_se_tpg;
1090 }
1091 
1092 static void tcm_loop_drop_naa_tpg(
1093 	struct se_portal_group *se_tpg)
1094 {
1095 	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1096 	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1097 				struct tcm_loop_tpg, tl_se_tpg);
1098 	struct tcm_loop_hba *tl_hba;
1099 	unsigned short tpgt;
1100 
1101 	tl_hba = tl_tpg->tl_hba;
1102 	tpgt = tl_tpg->tl_tpgt;
1103 	/*
1104 	 * Release the I_T Nexus for the Virtual target link if present
1105 	 */
1106 	tcm_loop_drop_nexus(tl_tpg);
1107 	/*
1108 	 * Deregister the tl_tpg as a emulated TCM Target Endpoint
1109 	 */
1110 	core_tpg_deregister(se_tpg);
1111 
1112 	tl_tpg->tl_hba = NULL;
1113 	tl_tpg->tl_tpgt = 0;
1114 
1115 	pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1116 		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1117 		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1118 }
1119 
1120 /* End items for tcm_loop_naa_cit */
1121 
1122 /* Start items for tcm_loop_cit */
1123 
1124 static struct se_wwn *tcm_loop_make_scsi_hba(
1125 	struct target_fabric_configfs *tf,
1126 	struct config_group *group,
1127 	const char *name)
1128 {
1129 	struct tcm_loop_hba *tl_hba;
1130 	struct Scsi_Host *sh;
1131 	char *ptr;
1132 	int ret, off = 0;
1133 
1134 	tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1135 	if (!tl_hba) {
1136 		pr_err("Unable to allocate struct tcm_loop_hba\n");
1137 		return ERR_PTR(-ENOMEM);
1138 	}
1139 	/*
1140 	 * Determine the emulated Protocol Identifier and Target Port Name
1141 	 * based on the incoming configfs directory name.
1142 	 */
1143 	ptr = strstr(name, "naa.");
1144 	if (ptr) {
1145 		tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1146 		goto check_len;
1147 	}
1148 	ptr = strstr(name, "fc.");
1149 	if (ptr) {
1150 		tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1151 		off = 3; /* Skip over "fc." */
1152 		goto check_len;
1153 	}
1154 	ptr = strstr(name, "iqn.");
1155 	if (!ptr) {
1156 		pr_err("Unable to locate prefix for emulated Target "
1157 				"Port: %s\n", name);
1158 		ret = -EINVAL;
1159 		goto out;
1160 	}
1161 	tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1162 
1163 check_len:
1164 	if (strlen(name) >= TL_WWN_ADDR_LEN) {
1165 		pr_err("Emulated NAA %s Address: %s, exceeds"
1166 			" max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1167 			TL_WWN_ADDR_LEN);
1168 		ret = -EINVAL;
1169 		goto out;
1170 	}
1171 	snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1172 
1173 	/*
1174 	 * Call device_register(tl_hba->dev) to register the emulated
1175 	 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1176 	 * device_register() callbacks in tcm_loop_driver_probe()
1177 	 */
1178 	ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1179 	if (ret)
1180 		goto out;
1181 
1182 	sh = tl_hba->sh;
1183 	tcm_loop_hba_no_cnt++;
1184 	pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1185 		" %s Address: %s at Linux/SCSI Host ID: %d\n",
1186 		tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1187 
1188 	return &tl_hba->tl_hba_wwn;
1189 out:
1190 	kfree(tl_hba);
1191 	return ERR_PTR(ret);
1192 }
1193 
1194 static void tcm_loop_drop_scsi_hba(
1195 	struct se_wwn *wwn)
1196 {
1197 	struct tcm_loop_hba *tl_hba = container_of(wwn,
1198 				struct tcm_loop_hba, tl_hba_wwn);
1199 
1200 	pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1201 		" %s Address: %s at Linux/SCSI Host ID: %d\n",
1202 		tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1203 		tl_hba->sh->host_no);
1204 	/*
1205 	 * Call device_unregister() on the original tl_hba->dev.
1206 	 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1207 	 * release *tl_hba;
1208 	 */
1209 	device_unregister(&tl_hba->dev);
1210 }
1211 
1212 /* Start items for tcm_loop_cit */
1213 static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1214 {
1215 	return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1216 }
1217 
1218 CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1219 
1220 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1221 	&tcm_loop_wwn_attr_version,
1222 	NULL,
1223 };
1224 
1225 /* End items for tcm_loop_cit */
1226 
1227 static const struct target_core_fabric_ops loop_ops = {
1228 	.module				= THIS_MODULE,
1229 	.name				= "loopback",
1230 	.get_fabric_name		= tcm_loop_get_fabric_name,
1231 	.tpg_get_wwn			= tcm_loop_get_endpoint_wwn,
1232 	.tpg_get_tag			= tcm_loop_get_tag,
1233 	.tpg_check_demo_mode		= tcm_loop_check_demo_mode,
1234 	.tpg_check_demo_mode_cache	= tcm_loop_check_demo_mode_cache,
1235 	.tpg_check_demo_mode_write_protect =
1236 				tcm_loop_check_demo_mode_write_protect,
1237 	.tpg_check_prod_mode_write_protect =
1238 				tcm_loop_check_prod_mode_write_protect,
1239 	.tpg_check_prot_fabric_only	= tcm_loop_check_prot_fabric_only,
1240 	.tpg_get_inst_index		= tcm_loop_get_inst_index,
1241 	.check_stop_free		= tcm_loop_check_stop_free,
1242 	.release_cmd			= tcm_loop_release_cmd,
1243 	.shutdown_session		= tcm_loop_shutdown_session,
1244 	.close_session			= tcm_loop_close_session,
1245 	.sess_get_index			= tcm_loop_sess_get_index,
1246 	.write_pending			= tcm_loop_write_pending,
1247 	.write_pending_status		= tcm_loop_write_pending_status,
1248 	.set_default_node_attributes	= tcm_loop_set_default_node_attributes,
1249 	.get_cmd_state			= tcm_loop_get_cmd_state,
1250 	.queue_data_in			= tcm_loop_queue_data_in,
1251 	.queue_status			= tcm_loop_queue_status,
1252 	.queue_tm_rsp			= tcm_loop_queue_tm_rsp,
1253 	.aborted_task			= tcm_loop_aborted_task,
1254 	.fabric_make_wwn		= tcm_loop_make_scsi_hba,
1255 	.fabric_drop_wwn		= tcm_loop_drop_scsi_hba,
1256 	.fabric_make_tpg		= tcm_loop_make_naa_tpg,
1257 	.fabric_drop_tpg		= tcm_loop_drop_naa_tpg,
1258 	.fabric_post_link		= tcm_loop_port_link,
1259 	.fabric_pre_unlink		= tcm_loop_port_unlink,
1260 	.tfc_wwn_attrs			= tcm_loop_wwn_attrs,
1261 	.tfc_tpg_base_attrs		= tcm_loop_tpg_attrs,
1262 	.tfc_tpg_attrib_attrs		= tcm_loop_tpg_attrib_attrs,
1263 };
1264 
1265 static int __init tcm_loop_fabric_init(void)
1266 {
1267 	int ret = -ENOMEM;
1268 
1269 	tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1270 	if (!tcm_loop_workqueue)
1271 		goto out;
1272 
1273 	tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1274 				sizeof(struct tcm_loop_cmd),
1275 				__alignof__(struct tcm_loop_cmd),
1276 				0, NULL);
1277 	if (!tcm_loop_cmd_cache) {
1278 		pr_debug("kmem_cache_create() for"
1279 			" tcm_loop_cmd_cache failed\n");
1280 		goto out_destroy_workqueue;
1281 	}
1282 
1283 	ret = tcm_loop_alloc_core_bus();
1284 	if (ret)
1285 		goto out_destroy_cache;
1286 
1287 	ret = target_register_template(&loop_ops);
1288 	if (ret)
1289 		goto out_release_core_bus;
1290 
1291 	return 0;
1292 
1293 out_release_core_bus:
1294 	tcm_loop_release_core_bus();
1295 out_destroy_cache:
1296 	kmem_cache_destroy(tcm_loop_cmd_cache);
1297 out_destroy_workqueue:
1298 	destroy_workqueue(tcm_loop_workqueue);
1299 out:
1300 	return ret;
1301 }
1302 
1303 static void __exit tcm_loop_fabric_exit(void)
1304 {
1305 	target_unregister_template(&loop_ops);
1306 	tcm_loop_release_core_bus();
1307 	kmem_cache_destroy(tcm_loop_cmd_cache);
1308 	destroy_workqueue(tcm_loop_workqueue);
1309 }
1310 
1311 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1312 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1313 MODULE_LICENSE("GPL");
1314 module_init(tcm_loop_fabric_init);
1315 module_exit(tcm_loop_fabric_exit);
1316