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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#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_show_info(struct seq_file *m, struct Scsi_Host *host)
83{
84	seq_printf(m, "tcm_loop_proc_info()\n");
85	return 0;
86}
87
88static int tcm_loop_driver_probe(struct device *);
89static int tcm_loop_driver_remove(struct device *);
90
91static int pseudo_lld_bus_match(struct device *dev,
92				struct device_driver *dev_driver)
93{
94	return 1;
95}
96
97static struct bus_type tcm_loop_lld_bus = {
98	.name			= "tcm_loop_bus",
99	.match			= pseudo_lld_bus_match,
100	.probe			= tcm_loop_driver_probe,
101	.remove			= tcm_loop_driver_remove,
102};
103
104static struct device_driver tcm_loop_driverfs = {
105	.name			= "tcm_loop",
106	.bus			= &tcm_loop_lld_bus,
107};
108/*
109 * Used with root_device_register() in tcm_loop_alloc_core_bus() below
110 */
111struct device *tcm_loop_primary;
112
113/*
114 * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
115 * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
116 */
117static int tcm_loop_change_queue_depth(
118	struct scsi_device *sdev,
119	int depth,
120	int reason)
121{
122	switch (reason) {
123	case SCSI_QDEPTH_DEFAULT:
124		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
125		break;
126	case SCSI_QDEPTH_QFULL:
127		scsi_track_queue_full(sdev, depth);
128		break;
129	case SCSI_QDEPTH_RAMP_UP:
130		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
131		break;
132	default:
133		return -EOPNOTSUPP;
134	}
135	return sdev->queue_depth;
136}
137
138static int tcm_loop_change_queue_type(struct scsi_device *sdev, int tag)
139{
140	if (sdev->tagged_supported) {
141		scsi_set_tag_type(sdev, tag);
142
143		if (tag)
144			scsi_activate_tcq(sdev, sdev->queue_depth);
145		else
146			scsi_deactivate_tcq(sdev, sdev->queue_depth);
147	} else
148		tag = 0;
149
150	return tag;
151}
152
153/*
154 * Locate the SAM Task Attr from struct scsi_cmnd *
155 */
156static int tcm_loop_sam_attr(struct scsi_cmnd *sc, int tag)
157{
158	if (sc->device->tagged_supported &&
159	    sc->device->ordered_tags && tag >= 0)
160		return MSG_ORDERED_TAG;
161
162	return MSG_SIMPLE_TAG;
163}
164
165static void tcm_loop_submission_work(struct work_struct *work)
166{
167	struct tcm_loop_cmd *tl_cmd =
168		container_of(work, struct tcm_loop_cmd, work);
169	struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
170	struct scsi_cmnd *sc = tl_cmd->sc;
171	struct tcm_loop_nexus *tl_nexus;
172	struct tcm_loop_hba *tl_hba;
173	struct tcm_loop_tpg *tl_tpg;
174	struct scatterlist *sgl_bidi = NULL;
175	u32 sgl_bidi_count = 0, transfer_length;
176	int rc;
177
178	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
179	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
180
181	/*
182	 * Ensure that this tl_tpg reference from the incoming sc->device->id
183	 * has already been configured via tcm_loop_make_naa_tpg().
184	 */
185	if (!tl_tpg->tl_hba) {
186		set_host_byte(sc, DID_NO_CONNECT);
187		goto out_done;
188	}
189	if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
190		set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
191		goto out_done;
192	}
193	tl_nexus = tl_hba->tl_nexus;
194	if (!tl_nexus) {
195		scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
196				" does not exist\n");
197		set_host_byte(sc, DID_ERROR);
198		goto out_done;
199	}
200	if (scsi_bidi_cmnd(sc)) {
201		struct scsi_data_buffer *sdb = scsi_in(sc);
202
203		sgl_bidi = sdb->table.sgl;
204		sgl_bidi_count = sdb->table.nents;
205		se_cmd->se_cmd_flags |= SCF_BIDI;
206
207	}
208
209	transfer_length = scsi_transfer_length(sc);
210	if (!scsi_prot_sg_count(sc) &&
211	    scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
212		se_cmd->prot_pto = true;
213		/*
214		 * loopback transport doesn't support
215		 * WRITE_GENERATE, READ_STRIP protection
216		 * information operations, go ahead unprotected.
217		 */
218		transfer_length = scsi_bufflen(sc);
219	}
220
221	rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
222			&tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
223			transfer_length, tcm_loop_sam_attr(sc, tl_cmd->sc_cmd_tag),
224			sc->sc_data_direction, 0,
225			scsi_sglist(sc), scsi_sg_count(sc),
226			sgl_bidi, sgl_bidi_count,
227			scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
228	if (rc < 0) {
229		set_host_byte(sc, DID_NO_CONNECT);
230		goto out_done;
231	}
232	return;
233
234out_done:
235	kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
236	sc->scsi_done(sc);
237	return;
238}
239
240/*
241 * ->queuecommand can be and usually is called from interrupt context, so
242 * defer the actual submission to a workqueue.
243 */
244static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
245{
246	struct tcm_loop_cmd *tl_cmd;
247
248	pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
249		" scsi_buf_len: %u\n", sc->device->host->host_no,
250		sc->device->id, sc->device->channel, sc->device->lun,
251		sc->cmnd[0], scsi_bufflen(sc));
252
253	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
254	if (!tl_cmd) {
255		pr_err("Unable to allocate struct tcm_loop_cmd\n");
256		set_host_byte(sc, DID_ERROR);
257		sc->scsi_done(sc);
258		return 0;
259	}
260
261	tl_cmd->sc = sc;
262	tl_cmd->sc_cmd_tag = sc->request->tag;
263	INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
264	queue_work(tcm_loop_workqueue, &tl_cmd->work);
265	return 0;
266}
267
268/*
269 * Called from SCSI EH process context to issue a LUN_RESET TMR
270 * to struct scsi_device
271 */
272static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
273			      struct tcm_loop_nexus *tl_nexus,
274			      int lun, int task, enum tcm_tmreq_table tmr)
275{
276	struct se_cmd *se_cmd = NULL;
277	struct se_session *se_sess;
278	struct se_portal_group *se_tpg;
279	struct tcm_loop_cmd *tl_cmd = NULL;
280	struct tcm_loop_tmr *tl_tmr = NULL;
281	int ret = TMR_FUNCTION_FAILED, rc;
282
283	tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
284	if (!tl_cmd) {
285		pr_err("Unable to allocate memory for tl_cmd\n");
286		return ret;
287	}
288
289	tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
290	if (!tl_tmr) {
291		pr_err("Unable to allocate memory for tl_tmr\n");
292		goto release;
293	}
294	init_waitqueue_head(&tl_tmr->tl_tmr_wait);
295
296	se_cmd = &tl_cmd->tl_se_cmd;
297	se_tpg = &tl_tpg->tl_se_tpg;
298	se_sess = tl_nexus->se_sess;
299	/*
300	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
301	 */
302	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
303				DMA_NONE, MSG_SIMPLE_TAG,
304				&tl_cmd->tl_sense_buf[0]);
305
306	rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
307	if (rc < 0)
308		goto release;
309
310	if (tmr == TMR_ABORT_TASK)
311		se_cmd->se_tmr_req->ref_task_tag = task;
312
313	/*
314	 * Locate the underlying TCM struct se_lun
315	 */
316	if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
317		ret = TMR_LUN_DOES_NOT_EXIST;
318		goto release;
319	}
320	/*
321	 * Queue the TMR to TCM Core and sleep waiting for
322	 * tcm_loop_queue_tm_rsp() to wake us up.
323	 */
324	transport_generic_handle_tmr(se_cmd);
325	wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
326	/*
327	 * The TMR LUN_RESET has completed, check the response status and
328	 * then release allocations.
329	 */
330	ret = se_cmd->se_tmr_req->response;
331release:
332	if (se_cmd)
333		transport_generic_free_cmd(se_cmd, 1);
334	else
335		kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
336	kfree(tl_tmr);
337	return ret;
338}
339
340static int tcm_loop_abort_task(struct scsi_cmnd *sc)
341{
342	struct tcm_loop_hba *tl_hba;
343	struct tcm_loop_nexus *tl_nexus;
344	struct tcm_loop_tpg *tl_tpg;
345	int ret = FAILED;
346
347	/*
348	 * Locate the tcm_loop_hba_t pointer
349	 */
350	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
351	/*
352	 * Locate the tl_nexus and se_sess pointers
353	 */
354	tl_nexus = tl_hba->tl_nexus;
355	if (!tl_nexus) {
356		pr_err("Unable to perform device reset without"
357				" active I_T Nexus\n");
358		return FAILED;
359	}
360
361	/*
362	 * Locate the tl_tpg pointer from TargetID in sc->device->id
363	 */
364	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
365	ret = tcm_loop_issue_tmr(tl_tpg, tl_nexus, sc->device->lun,
366				 sc->request->tag, TMR_ABORT_TASK);
367	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
368}
369
370/*
371 * Called from SCSI EH process context to issue a LUN_RESET TMR
372 * to struct scsi_device
373 */
374static int tcm_loop_device_reset(struct scsi_cmnd *sc)
375{
376	struct tcm_loop_hba *tl_hba;
377	struct tcm_loop_nexus *tl_nexus;
378	struct tcm_loop_tpg *tl_tpg;
379	int ret = FAILED;
380
381	/*
382	 * Locate the tcm_loop_hba_t pointer
383	 */
384	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
385	/*
386	 * Locate the tl_nexus and se_sess pointers
387	 */
388	tl_nexus = tl_hba->tl_nexus;
389	if (!tl_nexus) {
390		pr_err("Unable to perform device reset without"
391				" active I_T Nexus\n");
392		return FAILED;
393	}
394	/*
395	 * Locate the tl_tpg pointer from TargetID in sc->device->id
396	 */
397	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
398	ret = tcm_loop_issue_tmr(tl_tpg, tl_nexus, sc->device->lun,
399				 0, TMR_LUN_RESET);
400	return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
401}
402
403static int tcm_loop_target_reset(struct scsi_cmnd *sc)
404{
405	struct tcm_loop_hba *tl_hba;
406	struct tcm_loop_tpg *tl_tpg;
407
408	/*
409	 * Locate the tcm_loop_hba_t pointer
410	 */
411	tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
412	if (!tl_hba) {
413		pr_err("Unable to perform device reset without"
414				" active I_T Nexus\n");
415		return FAILED;
416	}
417	/*
418	 * Locate the tl_tpg pointer from TargetID in sc->device->id
419	 */
420	tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
421	if (tl_tpg) {
422		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
423		return SUCCESS;
424	}
425	return FAILED;
426}
427
428static int tcm_loop_slave_alloc(struct scsi_device *sd)
429{
430	set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
431	return 0;
432}
433
434static int tcm_loop_slave_configure(struct scsi_device *sd)
435{
436	if (sd->tagged_supported) {
437		scsi_activate_tcq(sd, sd->queue_depth);
438		scsi_adjust_queue_depth(sd, MSG_SIMPLE_TAG,
439					sd->host->cmd_per_lun);
440	} else {
441		scsi_adjust_queue_depth(sd, 0,
442					sd->host->cmd_per_lun);
443	}
444
445	return 0;
446}
447
448static struct scsi_host_template tcm_loop_driver_template = {
449	.show_info		= tcm_loop_show_info,
450	.proc_name		= "tcm_loopback",
451	.name			= "TCM_Loopback",
452	.queuecommand		= tcm_loop_queuecommand,
453	.change_queue_depth	= tcm_loop_change_queue_depth,
454	.change_queue_type	= tcm_loop_change_queue_type,
455	.eh_abort_handler = tcm_loop_abort_task,
456	.eh_device_reset_handler = tcm_loop_device_reset,
457	.eh_target_reset_handler = tcm_loop_target_reset,
458	.can_queue		= 1024,
459	.this_id		= -1,
460	.sg_tablesize		= 256,
461	.cmd_per_lun		= 1024,
462	.max_sectors		= 0xFFFF,
463	.use_clustering		= DISABLE_CLUSTERING,
464	.slave_alloc		= tcm_loop_slave_alloc,
465	.slave_configure	= tcm_loop_slave_configure,
466	.module			= THIS_MODULE,
467};
468
469static int tcm_loop_driver_probe(struct device *dev)
470{
471	struct tcm_loop_hba *tl_hba;
472	struct Scsi_Host *sh;
473	int error, host_prot;
474
475	tl_hba = to_tcm_loop_hba(dev);
476
477	sh = scsi_host_alloc(&tcm_loop_driver_template,
478			sizeof(struct tcm_loop_hba));
479	if (!sh) {
480		pr_err("Unable to allocate struct scsi_host\n");
481		return -ENODEV;
482	}
483	tl_hba->sh = sh;
484
485	/*
486	 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
487	 */
488	*((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
489	/*
490	 * Setup single ID, Channel and LUN for now..
491	 */
492	sh->max_id = 2;
493	sh->max_lun = 0;
494	sh->max_channel = 0;
495	sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
496
497	host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
498		    SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
499		    SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
500
501	scsi_host_set_prot(sh, host_prot);
502	scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
503
504	error = scsi_add_host(sh, &tl_hba->dev);
505	if (error) {
506		pr_err("%s: scsi_add_host failed\n", __func__);
507		scsi_host_put(sh);
508		return -ENODEV;
509	}
510	return 0;
511}
512
513static int tcm_loop_driver_remove(struct device *dev)
514{
515	struct tcm_loop_hba *tl_hba;
516	struct Scsi_Host *sh;
517
518	tl_hba = to_tcm_loop_hba(dev);
519	sh = tl_hba->sh;
520
521	scsi_remove_host(sh);
522	scsi_host_put(sh);
523	return 0;
524}
525
526static void tcm_loop_release_adapter(struct device *dev)
527{
528	struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
529
530	kfree(tl_hba);
531}
532
533/*
534 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
535 */
536static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
537{
538	int ret;
539
540	tl_hba->dev.bus = &tcm_loop_lld_bus;
541	tl_hba->dev.parent = tcm_loop_primary;
542	tl_hba->dev.release = &tcm_loop_release_adapter;
543	dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
544
545	ret = device_register(&tl_hba->dev);
546	if (ret) {
547		pr_err("device_register() failed for"
548				" tl_hba->dev: %d\n", ret);
549		return -ENODEV;
550	}
551
552	return 0;
553}
554
555/*
556 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
557 * tcm_loop SCSI bus.
558 */
559static int tcm_loop_alloc_core_bus(void)
560{
561	int ret;
562
563	tcm_loop_primary = root_device_register("tcm_loop_0");
564	if (IS_ERR(tcm_loop_primary)) {
565		pr_err("Unable to allocate tcm_loop_primary\n");
566		return PTR_ERR(tcm_loop_primary);
567	}
568
569	ret = bus_register(&tcm_loop_lld_bus);
570	if (ret) {
571		pr_err("bus_register() failed for tcm_loop_lld_bus\n");
572		goto dev_unreg;
573	}
574
575	ret = driver_register(&tcm_loop_driverfs);
576	if (ret) {
577		pr_err("driver_register() failed for"
578				"tcm_loop_driverfs\n");
579		goto bus_unreg;
580	}
581
582	pr_debug("Initialized TCM Loop Core Bus\n");
583	return ret;
584
585bus_unreg:
586	bus_unregister(&tcm_loop_lld_bus);
587dev_unreg:
588	root_device_unregister(tcm_loop_primary);
589	return ret;
590}
591
592static void tcm_loop_release_core_bus(void)
593{
594	driver_unregister(&tcm_loop_driverfs);
595	bus_unregister(&tcm_loop_lld_bus);
596	root_device_unregister(tcm_loop_primary);
597
598	pr_debug("Releasing TCM Loop Core BUS\n");
599}
600
601static char *tcm_loop_get_fabric_name(void)
602{
603	return "loopback";
604}
605
606static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
607{
608	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
609	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
610	/*
611	 * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
612	 * time based on the protocol dependent prefix of the passed configfs group.
613	 *
614	 * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
615	 * ProtocolID using target_core_fabric_lib.c symbols.
616	 */
617	switch (tl_hba->tl_proto_id) {
618	case SCSI_PROTOCOL_SAS:
619		return sas_get_fabric_proto_ident(se_tpg);
620	case SCSI_PROTOCOL_FCP:
621		return fc_get_fabric_proto_ident(se_tpg);
622	case SCSI_PROTOCOL_ISCSI:
623		return iscsi_get_fabric_proto_ident(se_tpg);
624	default:
625		pr_err("Unknown tl_proto_id: 0x%02x, using"
626			" SAS emulation\n", tl_hba->tl_proto_id);
627		break;
628	}
629
630	return sas_get_fabric_proto_ident(se_tpg);
631}
632
633static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
634{
635	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
636	/*
637	 * Return the passed NAA identifier for the SAS Target Port
638	 */
639	return &tl_tpg->tl_hba->tl_wwn_address[0];
640}
641
642static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
643{
644	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
645	/*
646	 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
647	 * to represent the SCSI Target Port.
648	 */
649	return tl_tpg->tl_tpgt;
650}
651
652static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
653{
654	return 1;
655}
656
657static u32 tcm_loop_get_pr_transport_id(
658	struct se_portal_group *se_tpg,
659	struct se_node_acl *se_nacl,
660	struct t10_pr_registration *pr_reg,
661	int *format_code,
662	unsigned char *buf)
663{
664	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
665	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
666
667	switch (tl_hba->tl_proto_id) {
668	case SCSI_PROTOCOL_SAS:
669		return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
670					format_code, buf);
671	case SCSI_PROTOCOL_FCP:
672		return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
673					format_code, buf);
674	case SCSI_PROTOCOL_ISCSI:
675		return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
676					format_code, buf);
677	default:
678		pr_err("Unknown tl_proto_id: 0x%02x, using"
679			" SAS emulation\n", tl_hba->tl_proto_id);
680		break;
681	}
682
683	return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
684			format_code, buf);
685}
686
687static u32 tcm_loop_get_pr_transport_id_len(
688	struct se_portal_group *se_tpg,
689	struct se_node_acl *se_nacl,
690	struct t10_pr_registration *pr_reg,
691	int *format_code)
692{
693	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
694	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
695
696	switch (tl_hba->tl_proto_id) {
697	case SCSI_PROTOCOL_SAS:
698		return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
699					format_code);
700	case SCSI_PROTOCOL_FCP:
701		return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
702					format_code);
703	case SCSI_PROTOCOL_ISCSI:
704		return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
705					format_code);
706	default:
707		pr_err("Unknown tl_proto_id: 0x%02x, using"
708			" SAS emulation\n", tl_hba->tl_proto_id);
709		break;
710	}
711
712	return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
713			format_code);
714}
715
716/*
717 * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
718 * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
719 */
720static char *tcm_loop_parse_pr_out_transport_id(
721	struct se_portal_group *se_tpg,
722	const char *buf,
723	u32 *out_tid_len,
724	char **port_nexus_ptr)
725{
726	struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
727	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
728
729	switch (tl_hba->tl_proto_id) {
730	case SCSI_PROTOCOL_SAS:
731		return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
732					port_nexus_ptr);
733	case SCSI_PROTOCOL_FCP:
734		return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
735					port_nexus_ptr);
736	case SCSI_PROTOCOL_ISCSI:
737		return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
738					port_nexus_ptr);
739	default:
740		pr_err("Unknown tl_proto_id: 0x%02x, using"
741			" SAS emulation\n", tl_hba->tl_proto_id);
742		break;
743	}
744
745	return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
746			port_nexus_ptr);
747}
748
749/*
750 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
751 * based upon the incoming fabric dependent SCSI Initiator Port
752 */
753static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
754{
755	return 1;
756}
757
758static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
759{
760	return 0;
761}
762
763/*
764 * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
765 * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
766 */
767static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
768{
769	return 0;
770}
771
772/*
773 * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
774 * never be called for TCM_Loop by target_core_fabric_configfs.c code.
775 * It has been added here as a nop for target_fabric_tf_ops_check()
776 */
777static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
778{
779	return 0;
780}
781
782static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
783	struct se_portal_group *se_tpg)
784{
785	struct tcm_loop_nacl *tl_nacl;
786
787	tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
788	if (!tl_nacl) {
789		pr_err("Unable to allocate struct tcm_loop_nacl\n");
790		return NULL;
791	}
792
793	return &tl_nacl->se_node_acl;
794}
795
796static void tcm_loop_tpg_release_fabric_acl(
797	struct se_portal_group *se_tpg,
798	struct se_node_acl *se_nacl)
799{
800	struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
801				struct tcm_loop_nacl, se_node_acl);
802
803	kfree(tl_nacl);
804}
805
806static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
807{
808	return 1;
809}
810
811static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
812{
813	return 1;
814}
815
816static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
817{
818	return;
819}
820
821static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
822{
823	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
824			struct tcm_loop_cmd, tl_se_cmd);
825
826	return tl_cmd->sc_cmd_tag;
827}
828
829static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
830{
831	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
832			struct tcm_loop_cmd, tl_se_cmd);
833
834	return tl_cmd->sc_cmd_state;
835}
836
837static int tcm_loop_shutdown_session(struct se_session *se_sess)
838{
839	return 0;
840}
841
842static void tcm_loop_close_session(struct se_session *se_sess)
843{
844	return;
845};
846
847static int tcm_loop_write_pending(struct se_cmd *se_cmd)
848{
849	/*
850	 * Since Linux/SCSI has already sent down a struct scsi_cmnd
851	 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
852	 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
853	 * format with transport_generic_map_mem_to_cmd().
854	 *
855	 * We now tell TCM to add this WRITE CDB directly into the TCM storage
856	 * object execution queue.
857	 */
858	target_execute_cmd(se_cmd);
859	return 0;
860}
861
862static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
863{
864	return 0;
865}
866
867static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
868{
869	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
870				struct tcm_loop_cmd, tl_se_cmd);
871	struct scsi_cmnd *sc = tl_cmd->sc;
872
873	pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
874		     " cdb: 0x%02x\n", sc, sc->cmnd[0]);
875
876	sc->result = SAM_STAT_GOOD;
877	set_host_byte(sc, DID_OK);
878	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
879	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
880		scsi_set_resid(sc, se_cmd->residual_count);
881	sc->scsi_done(sc);
882	return 0;
883}
884
885static int tcm_loop_queue_status(struct se_cmd *se_cmd)
886{
887	struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
888				struct tcm_loop_cmd, tl_se_cmd);
889	struct scsi_cmnd *sc = tl_cmd->sc;
890
891	pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
892			" cdb: 0x%02x\n", sc, sc->cmnd[0]);
893
894	if (se_cmd->sense_buffer &&
895	   ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
896	    (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
897
898		memcpy(sc->sense_buffer, se_cmd->sense_buffer,
899				SCSI_SENSE_BUFFERSIZE);
900		sc->result = SAM_STAT_CHECK_CONDITION;
901		set_driver_byte(sc, DRIVER_SENSE);
902	} else
903		sc->result = se_cmd->scsi_status;
904
905	set_host_byte(sc, DID_OK);
906	if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
907	    (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
908		scsi_set_resid(sc, se_cmd->residual_count);
909	sc->scsi_done(sc);
910	return 0;
911}
912
913static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
914{
915	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
916	struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
917	/*
918	 * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
919	 * and wake up the wait_queue_head_t in tcm_loop_device_reset()
920	 */
921	atomic_set(&tl_tmr->tmr_complete, 1);
922	wake_up(&tl_tmr->tl_tmr_wait);
923}
924
925static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
926{
927	return;
928}
929
930static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
931{
932	switch (tl_hba->tl_proto_id) {
933	case SCSI_PROTOCOL_SAS:
934		return "SAS";
935	case SCSI_PROTOCOL_FCP:
936		return "FCP";
937	case SCSI_PROTOCOL_ISCSI:
938		return "iSCSI";
939	default:
940		break;
941	}
942
943	return "Unknown";
944}
945
946/* Start items for tcm_loop_port_cit */
947
948static int tcm_loop_port_link(
949	struct se_portal_group *se_tpg,
950	struct se_lun *lun)
951{
952	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
953				struct tcm_loop_tpg, tl_se_tpg);
954	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
955
956	atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
957	/*
958	 * Add Linux/SCSI struct scsi_device by HCTL
959	 */
960	scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
961
962	pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
963	return 0;
964}
965
966static void tcm_loop_port_unlink(
967	struct se_portal_group *se_tpg,
968	struct se_lun *se_lun)
969{
970	struct scsi_device *sd;
971	struct tcm_loop_hba *tl_hba;
972	struct tcm_loop_tpg *tl_tpg;
973
974	tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
975	tl_hba = tl_tpg->tl_hba;
976
977	sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
978				se_lun->unpacked_lun);
979	if (!sd) {
980		pr_err("Unable to locate struct scsi_device for %d:%d:"
981			"%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
982		return;
983	}
984	/*
985	 * Remove Linux/SCSI struct scsi_device by HCTL
986	 */
987	scsi_remove_device(sd);
988	scsi_device_put(sd);
989
990	atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
991
992	pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
993}
994
995/* End items for tcm_loop_port_cit */
996
997/* Start items for tcm_loop_nexus_cit */
998
999static int tcm_loop_make_nexus(
1000	struct tcm_loop_tpg *tl_tpg,
1001	const char *name)
1002{
1003	struct se_portal_group *se_tpg;
1004	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1005	struct tcm_loop_nexus *tl_nexus;
1006	int ret = -ENOMEM;
1007
1008	if (tl_tpg->tl_hba->tl_nexus) {
1009		pr_debug("tl_tpg->tl_hba->tl_nexus already exists\n");
1010		return -EEXIST;
1011	}
1012	se_tpg = &tl_tpg->tl_se_tpg;
1013
1014	tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
1015	if (!tl_nexus) {
1016		pr_err("Unable to allocate struct tcm_loop_nexus\n");
1017		return -ENOMEM;
1018	}
1019	/*
1020	 * Initialize the struct se_session pointer
1021	 */
1022	tl_nexus->se_sess = transport_init_session(TARGET_PROT_ALL);
1023	if (IS_ERR(tl_nexus->se_sess)) {
1024		ret = PTR_ERR(tl_nexus->se_sess);
1025		goto out;
1026	}
1027	/*
1028	 * Since we are running in 'demo mode' this call with generate a
1029	 * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
1030	 * Initiator port name of the passed configfs group 'name'.
1031	 */
1032	tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1033				se_tpg, (unsigned char *)name);
1034	if (!tl_nexus->se_sess->se_node_acl) {
1035		transport_free_session(tl_nexus->se_sess);
1036		goto out;
1037	}
1038	/*
1039	 * Now, register the SAS I_T Nexus as active with the call to
1040	 * transport_register_session()
1041	 */
1042	__transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1043			tl_nexus->se_sess, tl_nexus);
1044	tl_tpg->tl_hba->tl_nexus = tl_nexus;
1045	pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1046		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1047		name);
1048	return 0;
1049
1050out:
1051	kfree(tl_nexus);
1052	return ret;
1053}
1054
1055static int tcm_loop_drop_nexus(
1056	struct tcm_loop_tpg *tpg)
1057{
1058	struct se_session *se_sess;
1059	struct tcm_loop_nexus *tl_nexus;
1060	struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1061
1062	if (!tl_hba)
1063		return -ENODEV;
1064
1065	tl_nexus = tl_hba->tl_nexus;
1066	if (!tl_nexus)
1067		return -ENODEV;
1068
1069	se_sess = tl_nexus->se_sess;
1070	if (!se_sess)
1071		return -ENODEV;
1072
1073	if (atomic_read(&tpg->tl_tpg_port_count)) {
1074		pr_err("Unable to remove TCM_Loop I_T Nexus with"
1075			" active TPG port count: %d\n",
1076			atomic_read(&tpg->tl_tpg_port_count));
1077		return -EPERM;
1078	}
1079
1080	pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1081		" %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1082		tl_nexus->se_sess->se_node_acl->initiatorname);
1083	/*
1084	 * Release the SCSI I_T Nexus to the emulated SAS Target Port
1085	 */
1086	transport_deregister_session(tl_nexus->se_sess);
1087	tpg->tl_hba->tl_nexus = NULL;
1088	kfree(tl_nexus);
1089	return 0;
1090}
1091
1092/* End items for tcm_loop_nexus_cit */
1093
1094static ssize_t tcm_loop_tpg_show_nexus(
1095	struct se_portal_group *se_tpg,
1096	char *page)
1097{
1098	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1099			struct tcm_loop_tpg, tl_se_tpg);
1100	struct tcm_loop_nexus *tl_nexus;
1101	ssize_t ret;
1102
1103	tl_nexus = tl_tpg->tl_hba->tl_nexus;
1104	if (!tl_nexus)
1105		return -ENODEV;
1106
1107	ret = snprintf(page, PAGE_SIZE, "%s\n",
1108		tl_nexus->se_sess->se_node_acl->initiatorname);
1109
1110	return ret;
1111}
1112
1113static ssize_t tcm_loop_tpg_store_nexus(
1114	struct se_portal_group *se_tpg,
1115	const char *page,
1116	size_t count)
1117{
1118	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1119			struct tcm_loop_tpg, tl_se_tpg);
1120	struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1121	unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1122	int ret;
1123	/*
1124	 * Shutdown the active I_T nexus if 'NULL' is passed..
1125	 */
1126	if (!strncmp(page, "NULL", 4)) {
1127		ret = tcm_loop_drop_nexus(tl_tpg);
1128		return (!ret) ? count : ret;
1129	}
1130	/*
1131	 * Otherwise make sure the passed virtual Initiator port WWN matches
1132	 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1133	 * tcm_loop_make_nexus()
1134	 */
1135	if (strlen(page) >= TL_WWN_ADDR_LEN) {
1136		pr_err("Emulated NAA Sas Address: %s, exceeds"
1137				" max: %d\n", page, TL_WWN_ADDR_LEN);
1138		return -EINVAL;
1139	}
1140	snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1141
1142	ptr = strstr(i_port, "naa.");
1143	if (ptr) {
1144		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1145			pr_err("Passed SAS Initiator Port %s does not"
1146				" match target port protoid: %s\n", i_port,
1147				tcm_loop_dump_proto_id(tl_hba));
1148			return -EINVAL;
1149		}
1150		port_ptr = &i_port[0];
1151		goto check_newline;
1152	}
1153	ptr = strstr(i_port, "fc.");
1154	if (ptr) {
1155		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1156			pr_err("Passed FCP Initiator Port %s does not"
1157				" match target port protoid: %s\n", i_port,
1158				tcm_loop_dump_proto_id(tl_hba));
1159			return -EINVAL;
1160		}
1161		port_ptr = &i_port[3]; /* Skip over "fc." */
1162		goto check_newline;
1163	}
1164	ptr = strstr(i_port, "iqn.");
1165	if (ptr) {
1166		if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1167			pr_err("Passed iSCSI Initiator Port %s does not"
1168				" match target port protoid: %s\n", i_port,
1169				tcm_loop_dump_proto_id(tl_hba));
1170			return -EINVAL;
1171		}
1172		port_ptr = &i_port[0];
1173		goto check_newline;
1174	}
1175	pr_err("Unable to locate prefix for emulated Initiator Port:"
1176			" %s\n", i_port);
1177	return -EINVAL;
1178	/*
1179	 * Clear any trailing newline for the NAA WWN
1180	 */
1181check_newline:
1182	if (i_port[strlen(i_port)-1] == '\n')
1183		i_port[strlen(i_port)-1] = '\0';
1184
1185	ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1186	if (ret < 0)
1187		return ret;
1188
1189	return count;
1190}
1191
1192TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1193
1194static ssize_t tcm_loop_tpg_show_transport_status(
1195	struct se_portal_group *se_tpg,
1196	char *page)
1197{
1198	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1199			struct tcm_loop_tpg, tl_se_tpg);
1200	const char *status = NULL;
1201	ssize_t ret = -EINVAL;
1202
1203	switch (tl_tpg->tl_transport_status) {
1204	case TCM_TRANSPORT_ONLINE:
1205		status = "online";
1206		break;
1207	case TCM_TRANSPORT_OFFLINE:
1208		status = "offline";
1209		break;
1210	default:
1211		break;
1212	}
1213
1214	if (status)
1215		ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1216
1217	return ret;
1218}
1219
1220static ssize_t tcm_loop_tpg_store_transport_status(
1221	struct se_portal_group *se_tpg,
1222	const char *page,
1223	size_t count)
1224{
1225	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1226			struct tcm_loop_tpg, tl_se_tpg);
1227
1228	if (!strncmp(page, "online", 6)) {
1229		tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1230		return count;
1231	}
1232	if (!strncmp(page, "offline", 7)) {
1233		tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1234		return count;
1235	}
1236	return -EINVAL;
1237}
1238
1239TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1240
1241static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1242	&tcm_loop_tpg_nexus.attr,
1243	&tcm_loop_tpg_transport_status.attr,
1244	NULL,
1245};
1246
1247/* Start items for tcm_loop_naa_cit */
1248
1249static struct se_portal_group *tcm_loop_make_naa_tpg(
1250	struct se_wwn *wwn,
1251	struct config_group *group,
1252	const char *name)
1253{
1254	struct tcm_loop_hba *tl_hba = container_of(wwn,
1255			struct tcm_loop_hba, tl_hba_wwn);
1256	struct tcm_loop_tpg *tl_tpg;
1257	char *tpgt_str, *end_ptr;
1258	int ret;
1259	unsigned short int tpgt;
1260
1261	tpgt_str = strstr(name, "tpgt_");
1262	if (!tpgt_str) {
1263		pr_err("Unable to locate \"tpgt_#\" directory"
1264				" group\n");
1265		return ERR_PTR(-EINVAL);
1266	}
1267	tpgt_str += 5; /* Skip ahead of "tpgt_" */
1268	tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1269
1270	if (tpgt >= TL_TPGS_PER_HBA) {
1271		pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1272				" %u\n", tpgt, TL_TPGS_PER_HBA);
1273		return ERR_PTR(-EINVAL);
1274	}
1275	tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1276	tl_tpg->tl_hba = tl_hba;
1277	tl_tpg->tl_tpgt = tpgt;
1278	/*
1279	 * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1280	 */
1281	ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1282			wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1283			TRANSPORT_TPG_TYPE_NORMAL);
1284	if (ret < 0)
1285		return ERR_PTR(-ENOMEM);
1286
1287	pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1288		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1289		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1290
1291	return &tl_tpg->tl_se_tpg;
1292}
1293
1294static void tcm_loop_drop_naa_tpg(
1295	struct se_portal_group *se_tpg)
1296{
1297	struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1298	struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1299				struct tcm_loop_tpg, tl_se_tpg);
1300	struct tcm_loop_hba *tl_hba;
1301	unsigned short tpgt;
1302
1303	tl_hba = tl_tpg->tl_hba;
1304	tpgt = tl_tpg->tl_tpgt;
1305	/*
1306	 * Release the I_T Nexus for the Virtual SAS link if present
1307	 */
1308	tcm_loop_drop_nexus(tl_tpg);
1309	/*
1310	 * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1311	 */
1312	core_tpg_deregister(se_tpg);
1313
1314	tl_tpg->tl_hba = NULL;
1315	tl_tpg->tl_tpgt = 0;
1316
1317	pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1318		" Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1319		config_item_name(&wwn->wwn_group.cg_item), tpgt);
1320}
1321
1322/* End items for tcm_loop_naa_cit */
1323
1324/* Start items for tcm_loop_cit */
1325
1326static struct se_wwn *tcm_loop_make_scsi_hba(
1327	struct target_fabric_configfs *tf,
1328	struct config_group *group,
1329	const char *name)
1330{
1331	struct tcm_loop_hba *tl_hba;
1332	struct Scsi_Host *sh;
1333	char *ptr;
1334	int ret, off = 0;
1335
1336	tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1337	if (!tl_hba) {
1338		pr_err("Unable to allocate struct tcm_loop_hba\n");
1339		return ERR_PTR(-ENOMEM);
1340	}
1341	/*
1342	 * Determine the emulated Protocol Identifier and Target Port Name
1343	 * based on the incoming configfs directory name.
1344	 */
1345	ptr = strstr(name, "naa.");
1346	if (ptr) {
1347		tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1348		goto check_len;
1349	}
1350	ptr = strstr(name, "fc.");
1351	if (ptr) {
1352		tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1353		off = 3; /* Skip over "fc." */
1354		goto check_len;
1355	}
1356	ptr = strstr(name, "iqn.");
1357	if (!ptr) {
1358		pr_err("Unable to locate prefix for emulated Target "
1359				"Port: %s\n", name);
1360		ret = -EINVAL;
1361		goto out;
1362	}
1363	tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1364
1365check_len:
1366	if (strlen(name) >= TL_WWN_ADDR_LEN) {
1367		pr_err("Emulated NAA %s Address: %s, exceeds"
1368			" max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1369			TL_WWN_ADDR_LEN);
1370		ret = -EINVAL;
1371		goto out;
1372	}
1373	snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1374
1375	/*
1376	 * Call device_register(tl_hba->dev) to register the emulated
1377	 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1378	 * device_register() callbacks in tcm_loop_driver_probe()
1379	 */
1380	ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1381	if (ret)
1382		goto out;
1383
1384	sh = tl_hba->sh;
1385	tcm_loop_hba_no_cnt++;
1386	pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1387		" %s Address: %s at Linux/SCSI Host ID: %d\n",
1388		tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1389
1390	return &tl_hba->tl_hba_wwn;
1391out:
1392	kfree(tl_hba);
1393	return ERR_PTR(ret);
1394}
1395
1396static void tcm_loop_drop_scsi_hba(
1397	struct se_wwn *wwn)
1398{
1399	struct tcm_loop_hba *tl_hba = container_of(wwn,
1400				struct tcm_loop_hba, tl_hba_wwn);
1401
1402	pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1403		" SAS Address: %s at Linux/SCSI Host ID: %d\n",
1404		tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1405	/*
1406	 * Call device_unregister() on the original tl_hba->dev.
1407	 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1408	 * release *tl_hba;
1409	 */
1410	device_unregister(&tl_hba->dev);
1411}
1412
1413/* Start items for tcm_loop_cit */
1414static ssize_t tcm_loop_wwn_show_attr_version(
1415	struct target_fabric_configfs *tf,
1416	char *page)
1417{
1418	return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1419}
1420
1421TF_WWN_ATTR_RO(tcm_loop, version);
1422
1423static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1424	&tcm_loop_wwn_version.attr,
1425	NULL,
1426};
1427
1428/* End items for tcm_loop_cit */
1429
1430static int tcm_loop_register_configfs(void)
1431{
1432	struct target_fabric_configfs *fabric;
1433	int ret;
1434	/*
1435	 * Set the TCM Loop HBA counter to zero
1436	 */
1437	tcm_loop_hba_no_cnt = 0;
1438	/*
1439	 * Register the top level struct config_item_type with TCM core
1440	 */
1441	fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1442	if (IS_ERR(fabric)) {
1443		pr_err("tcm_loop_register_configfs() failed!\n");
1444		return PTR_ERR(fabric);
1445	}
1446	/*
1447	 * Setup the fabric API of function pointers used by target_core_mod
1448	 */
1449	fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1450	fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1451	fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1452	fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1453	fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1454	fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1455	fabric->tf_ops.tpg_get_pr_transport_id_len =
1456					&tcm_loop_get_pr_transport_id_len;
1457	fabric->tf_ops.tpg_parse_pr_out_transport_id =
1458					&tcm_loop_parse_pr_out_transport_id;
1459	fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1460	fabric->tf_ops.tpg_check_demo_mode_cache =
1461					&tcm_loop_check_demo_mode_cache;
1462	fabric->tf_ops.tpg_check_demo_mode_write_protect =
1463					&tcm_loop_check_demo_mode_write_protect;
1464	fabric->tf_ops.tpg_check_prod_mode_write_protect =
1465					&tcm_loop_check_prod_mode_write_protect;
1466	/*
1467	 * The TCM loopback fabric module runs in demo-mode to a local
1468	 * virtual SCSI device, so fabric dependent initator ACLs are
1469	 * not required.
1470	 */
1471	fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1472	fabric->tf_ops.tpg_release_fabric_acl =
1473					&tcm_loop_tpg_release_fabric_acl;
1474	fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1475	/*
1476	 * Used for setting up remaining TCM resources in process context
1477	 */
1478	fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1479	fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1480	fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1481	fabric->tf_ops.close_session = &tcm_loop_close_session;
1482	fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1483	fabric->tf_ops.sess_get_initiator_sid = NULL;
1484	fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1485	fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1486	/*
1487	 * Not used for TCM loopback
1488	 */
1489	fabric->tf_ops.set_default_node_attributes =
1490					&tcm_loop_set_default_node_attributes;
1491	fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1492	fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1493	fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1494	fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1495	fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1496	fabric->tf_ops.aborted_task = &tcm_loop_aborted_task;
1497
1498	/*
1499	 * Setup function pointers for generic logic in target_core_fabric_configfs.c
1500	 */
1501	fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1502	fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1503	fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1504	fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1505	/*
1506	 * fabric_post_link() and fabric_pre_unlink() are used for
1507	 * registration and release of TCM Loop Virtual SCSI LUNs.
1508	 */
1509	fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1510	fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1511	fabric->tf_ops.fabric_make_np = NULL;
1512	fabric->tf_ops.fabric_drop_np = NULL;
1513	/*
1514	 * Setup default attribute lists for various fabric->tf_cit_tmpl
1515	 */
1516	fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1517	fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1518	fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
1519	fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
1520	fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
1521	/*
1522	 * Once fabric->tf_ops has been setup, now register the fabric for
1523	 * use within TCM
1524	 */
1525	ret = target_fabric_configfs_register(fabric);
1526	if (ret < 0) {
1527		pr_err("target_fabric_configfs_register() for"
1528				" TCM_Loop failed!\n");
1529		target_fabric_configfs_free(fabric);
1530		return -1;
1531	}
1532	/*
1533	 * Setup our local pointer to *fabric.
1534	 */
1535	tcm_loop_fabric_configfs = fabric;
1536	pr_debug("TCM_LOOP[0] - Set fabric ->"
1537			" tcm_loop_fabric_configfs\n");
1538	return 0;
1539}
1540
1541static void tcm_loop_deregister_configfs(void)
1542{
1543	if (!tcm_loop_fabric_configfs)
1544		return;
1545
1546	target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1547	tcm_loop_fabric_configfs = NULL;
1548	pr_debug("TCM_LOOP[0] - Cleared"
1549				" tcm_loop_fabric_configfs\n");
1550}
1551
1552static int __init tcm_loop_fabric_init(void)
1553{
1554	int ret = -ENOMEM;
1555
1556	tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1557	if (!tcm_loop_workqueue)
1558		goto out;
1559
1560	tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1561				sizeof(struct tcm_loop_cmd),
1562				__alignof__(struct tcm_loop_cmd),
1563				0, NULL);
1564	if (!tcm_loop_cmd_cache) {
1565		pr_debug("kmem_cache_create() for"
1566			" tcm_loop_cmd_cache failed\n");
1567		goto out_destroy_workqueue;
1568	}
1569
1570	ret = tcm_loop_alloc_core_bus();
1571	if (ret)
1572		goto out_destroy_cache;
1573
1574	ret = tcm_loop_register_configfs();
1575	if (ret)
1576		goto out_release_core_bus;
1577
1578	return 0;
1579
1580out_release_core_bus:
1581	tcm_loop_release_core_bus();
1582out_destroy_cache:
1583	kmem_cache_destroy(tcm_loop_cmd_cache);
1584out_destroy_workqueue:
1585	destroy_workqueue(tcm_loop_workqueue);
1586out:
1587	return ret;
1588}
1589
1590static void __exit tcm_loop_fabric_exit(void)
1591{
1592	tcm_loop_deregister_configfs();
1593	tcm_loop_release_core_bus();
1594	kmem_cache_destroy(tcm_loop_cmd_cache);
1595	destroy_workqueue(tcm_loop_workqueue);
1596}
1597
1598MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1599MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1600MODULE_LICENSE("GPL");
1601module_init(tcm_loop_fabric_init);
1602module_exit(tcm_loop_fabric_exit);
1603