GNU Linux-libre 4.19.314-gnu1
[releases.git] / drivers / target / loopback / tcm_loop.c
1 /*******************************************************************************
2  *
3  * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
4  * for emulated SAS initiator ports
5  *
6  * © Copyright 2011-2013 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         return transport_generic_free_cmd(se_cmd, 0);
55 }
56
57 static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
58 {
59         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
60                                 struct tcm_loop_cmd, tl_se_cmd);
61
62         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
63 }
64
65 static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
66 {
67         seq_puts(m, "tcm_loop_proc_info()\n");
68         return 0;
69 }
70
71 static int tcm_loop_driver_probe(struct device *);
72 static int tcm_loop_driver_remove(struct device *);
73
74 static int pseudo_lld_bus_match(struct device *dev,
75                                 struct device_driver *dev_driver)
76 {
77         return 1;
78 }
79
80 static struct bus_type tcm_loop_lld_bus = {
81         .name                   = "tcm_loop_bus",
82         .match                  = pseudo_lld_bus_match,
83         .probe                  = tcm_loop_driver_probe,
84         .remove                 = tcm_loop_driver_remove,
85 };
86
87 static struct device_driver tcm_loop_driverfs = {
88         .name                   = "tcm_loop",
89         .bus                    = &tcm_loop_lld_bus,
90 };
91 /*
92  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
93  */
94 static struct device *tcm_loop_primary;
95
96 static void tcm_loop_submission_work(struct work_struct *work)
97 {
98         struct tcm_loop_cmd *tl_cmd =
99                 container_of(work, struct tcm_loop_cmd, work);
100         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
101         struct scsi_cmnd *sc = tl_cmd->sc;
102         struct tcm_loop_nexus *tl_nexus;
103         struct tcm_loop_hba *tl_hba;
104         struct tcm_loop_tpg *tl_tpg;
105         struct scatterlist *sgl_bidi = NULL;
106         u32 sgl_bidi_count = 0, transfer_length;
107         int rc;
108
109         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
110         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
111
112         /*
113          * Ensure that this tl_tpg reference from the incoming sc->device->id
114          * has already been configured via tcm_loop_make_naa_tpg().
115          */
116         if (!tl_tpg->tl_hba) {
117                 set_host_byte(sc, DID_NO_CONNECT);
118                 goto out_done;
119         }
120         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
121                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
122                 goto out_done;
123         }
124         tl_nexus = tl_tpg->tl_nexus;
125         if (!tl_nexus) {
126                 scmd_printk(KERN_ERR, sc,
127                             "TCM_Loop I_T Nexus does not exist\n");
128                 set_host_byte(sc, DID_ERROR);
129                 goto out_done;
130         }
131         if (scsi_bidi_cmnd(sc)) {
132                 struct scsi_data_buffer *sdb = scsi_in(sc);
133
134                 sgl_bidi = sdb->table.sgl;
135                 sgl_bidi_count = sdb->table.nents;
136                 se_cmd->se_cmd_flags |= SCF_BIDI;
137
138         }
139
140         transfer_length = scsi_transfer_length(sc);
141         if (!scsi_prot_sg_count(sc) &&
142             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
143                 se_cmd->prot_pto = true;
144                 /*
145                  * loopback transport doesn't support
146                  * WRITE_GENERATE, READ_STRIP protection
147                  * information operations, go ahead unprotected.
148                  */
149                 transfer_length = scsi_bufflen(sc);
150         }
151
152         se_cmd->tag = tl_cmd->sc_cmd_tag;
153         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
154                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
155                         transfer_length, TCM_SIMPLE_TAG,
156                         sc->sc_data_direction, 0,
157                         scsi_sglist(sc), scsi_sg_count(sc),
158                         sgl_bidi, sgl_bidi_count,
159                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
160         if (rc < 0) {
161                 set_host_byte(sc, DID_NO_CONNECT);
162                 goto out_done;
163         }
164         return;
165
166 out_done:
167         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
168         sc->scsi_done(sc);
169 }
170
171 /*
172  * ->queuecommand can be and usually is called from interrupt context, so
173  * defer the actual submission to a workqueue.
174  */
175 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
176 {
177         struct tcm_loop_cmd *tl_cmd;
178
179         pr_debug("%s() %d:%d:%d:%llu got CDB: 0x%02x scsi_buf_len: %u\n",
180                  __func__, sc->device->host->host_no, sc->device->id,
181                  sc->device->channel, sc->device->lun, sc->cmnd[0],
182                  scsi_bufflen(sc));
183
184         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
185         if (!tl_cmd) {
186                 set_host_byte(sc, DID_ERROR);
187                 sc->scsi_done(sc);
188                 return 0;
189         }
190
191         tl_cmd->sc = sc;
192         tl_cmd->sc_cmd_tag = sc->request->tag;
193         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
194         queue_work(tcm_loop_workqueue, &tl_cmd->work);
195         return 0;
196 }
197
198 /*
199  * Called from SCSI EH process context to issue a LUN_RESET TMR
200  * to struct scsi_device
201  */
202 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
203                               u64 lun, int task, enum tcm_tmreq_table tmr)
204 {
205         struct se_cmd *se_cmd;
206         struct se_session *se_sess;
207         struct tcm_loop_nexus *tl_nexus;
208         struct tcm_loop_cmd *tl_cmd;
209         int ret = TMR_FUNCTION_FAILED, rc;
210
211         /*
212          * Locate the tl_nexus and se_sess pointers
213          */
214         tl_nexus = tl_tpg->tl_nexus;
215         if (!tl_nexus) {
216                 pr_err("Unable to perform device reset without active I_T Nexus\n");
217                 return ret;
218         }
219
220         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
221         if (!tl_cmd)
222                 return ret;
223
224         init_completion(&tl_cmd->tmr_done);
225
226         se_cmd = &tl_cmd->tl_se_cmd;
227         se_sess = tl_tpg->tl_nexus->se_sess;
228
229         rc = target_submit_tmr(se_cmd, se_sess, tl_cmd->tl_sense_buf, lun,
230                                NULL, tmr, GFP_KERNEL, task,
231                                TARGET_SCF_ACK_KREF);
232         if (rc < 0)
233                 goto release;
234         wait_for_completion(&tl_cmd->tmr_done);
235         ret = se_cmd->se_tmr_req->response;
236         target_put_sess_cmd(se_cmd);
237
238 out:
239         return ret;
240
241 release:
242         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
243         goto out;
244 }
245
246 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
247 {
248         struct tcm_loop_hba *tl_hba;
249         struct tcm_loop_tpg *tl_tpg;
250         int ret = FAILED;
251
252         /*
253          * Locate the tcm_loop_hba_t pointer
254          */
255         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
256         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
257         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
258                                  sc->request->tag, TMR_ABORT_TASK);
259         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
260 }
261
262 /*
263  * Called from SCSI EH process context to issue a LUN_RESET TMR
264  * to struct scsi_device
265  */
266 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
267 {
268         struct tcm_loop_hba *tl_hba;
269         struct tcm_loop_tpg *tl_tpg;
270         int ret = FAILED;
271
272         /*
273          * Locate the tcm_loop_hba_t pointer
274          */
275         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
276         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
277
278         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
279                                  0, TMR_LUN_RESET);
280         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
281 }
282
283 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
284 {
285         struct tcm_loop_hba *tl_hba;
286         struct tcm_loop_tpg *tl_tpg;
287
288         /*
289          * Locate the tcm_loop_hba_t pointer
290          */
291         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
292         if (!tl_hba) {
293                 pr_err("Unable to perform device reset without active I_T Nexus\n");
294                 return FAILED;
295         }
296         /*
297          * Locate the tl_tpg pointer from TargetID in sc->device->id
298          */
299         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
300         if (tl_tpg) {
301                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
302                 return SUCCESS;
303         }
304         return FAILED;
305 }
306
307 static int tcm_loop_slave_alloc(struct scsi_device *sd)
308 {
309         blk_queue_flag_set(QUEUE_FLAG_BIDI, sd->request_queue);
310         return 0;
311 }
312
313 static struct scsi_host_template tcm_loop_driver_template = {
314         .show_info              = tcm_loop_show_info,
315         .proc_name              = "tcm_loopback",
316         .name                   = "TCM_Loopback",
317         .queuecommand           = tcm_loop_queuecommand,
318         .change_queue_depth     = scsi_change_queue_depth,
319         .eh_abort_handler = tcm_loop_abort_task,
320         .eh_device_reset_handler = tcm_loop_device_reset,
321         .eh_target_reset_handler = tcm_loop_target_reset,
322         .can_queue              = 1024,
323         .this_id                = -1,
324         .sg_tablesize           = 256,
325         .cmd_per_lun            = 1024,
326         .max_sectors            = 0xFFFF,
327         .use_clustering         = DISABLE_CLUSTERING,
328         .slave_alloc            = tcm_loop_slave_alloc,
329         .module                 = THIS_MODULE,
330         .track_queue_depth      = 1,
331 };
332
333 static int tcm_loop_driver_probe(struct device *dev)
334 {
335         struct tcm_loop_hba *tl_hba;
336         struct Scsi_Host *sh;
337         int error, host_prot;
338
339         tl_hba = to_tcm_loop_hba(dev);
340
341         sh = scsi_host_alloc(&tcm_loop_driver_template,
342                         sizeof(struct tcm_loop_hba));
343         if (!sh) {
344                 pr_err("Unable to allocate struct scsi_host\n");
345                 return -ENODEV;
346         }
347         tl_hba->sh = sh;
348
349         /*
350          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
351          */
352         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
353         /*
354          * Setup single ID, Channel and LUN for now..
355          */
356         sh->max_id = 2;
357         sh->max_lun = 0;
358         sh->max_channel = 0;
359         sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
360
361         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
362                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
363                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
364
365         scsi_host_set_prot(sh, host_prot);
366         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
367
368         error = scsi_add_host(sh, &tl_hba->dev);
369         if (error) {
370                 pr_err("%s: scsi_add_host failed\n", __func__);
371                 scsi_host_put(sh);
372                 return -ENODEV;
373         }
374         return 0;
375 }
376
377 static int tcm_loop_driver_remove(struct device *dev)
378 {
379         struct tcm_loop_hba *tl_hba;
380         struct Scsi_Host *sh;
381
382         tl_hba = to_tcm_loop_hba(dev);
383         sh = tl_hba->sh;
384
385         scsi_remove_host(sh);
386         scsi_host_put(sh);
387         return 0;
388 }
389
390 static void tcm_loop_release_adapter(struct device *dev)
391 {
392         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
393
394         kfree(tl_hba);
395 }
396
397 /*
398  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
399  */
400 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
401 {
402         int ret;
403
404         tl_hba->dev.bus = &tcm_loop_lld_bus;
405         tl_hba->dev.parent = tcm_loop_primary;
406         tl_hba->dev.release = &tcm_loop_release_adapter;
407         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
408
409         ret = device_register(&tl_hba->dev);
410         if (ret) {
411                 pr_err("device_register() failed for tl_hba->dev: %d\n", ret);
412                 put_device(&tl_hba->dev);
413                 return -ENODEV;
414         }
415
416         return 0;
417 }
418
419 /*
420  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
421  * tcm_loop SCSI bus.
422  */
423 static int tcm_loop_alloc_core_bus(void)
424 {
425         int ret;
426
427         tcm_loop_primary = root_device_register("tcm_loop_0");
428         if (IS_ERR(tcm_loop_primary)) {
429                 pr_err("Unable to allocate tcm_loop_primary\n");
430                 return PTR_ERR(tcm_loop_primary);
431         }
432
433         ret = bus_register(&tcm_loop_lld_bus);
434         if (ret) {
435                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
436                 goto dev_unreg;
437         }
438
439         ret = driver_register(&tcm_loop_driverfs);
440         if (ret) {
441                 pr_err("driver_register() failed for tcm_loop_driverfs\n");
442                 goto bus_unreg;
443         }
444
445         pr_debug("Initialized TCM Loop Core Bus\n");
446         return ret;
447
448 bus_unreg:
449         bus_unregister(&tcm_loop_lld_bus);
450 dev_unreg:
451         root_device_unregister(tcm_loop_primary);
452         return ret;
453 }
454
455 static void tcm_loop_release_core_bus(void)
456 {
457         driver_unregister(&tcm_loop_driverfs);
458         bus_unregister(&tcm_loop_lld_bus);
459         root_device_unregister(tcm_loop_primary);
460
461         pr_debug("Releasing TCM Loop Core BUS\n");
462 }
463
464 static char *tcm_loop_get_fabric_name(void)
465 {
466         return "loopback";
467 }
468
469 static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
470 {
471         return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
472 }
473
474 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
475 {
476         /*
477          * Return the passed NAA identifier for the Target Port
478          */
479         return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
480 }
481
482 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
483 {
484         /*
485          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
486          * to represent the SCSI Target Port.
487          */
488         return tl_tpg(se_tpg)->tl_tpgt;
489 }
490
491 /*
492  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
493  * based upon the incoming fabric dependent SCSI Initiator Port
494  */
495 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
496 {
497         return 1;
498 }
499
500 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
501 {
502         return 0;
503 }
504
505 /*
506  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
507  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
508  */
509 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
510 {
511         return 0;
512 }
513
514 /*
515  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
516  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
517  * It has been added here as a nop for target_fabric_tf_ops_check()
518  */
519 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
520 {
521         return 0;
522 }
523
524 static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
525 {
526         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
527                                                    tl_se_tpg);
528         return tl_tpg->tl_fabric_prot_type;
529 }
530
531 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
532 {
533         return 1;
534 }
535
536 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
537 {
538         return 1;
539 }
540
541 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
542 {
543         return;
544 }
545
546 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
547 {
548         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
549                         struct tcm_loop_cmd, tl_se_cmd);
550
551         return tl_cmd->sc_cmd_state;
552 }
553
554 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
555 {
556         /*
557          * Since Linux/SCSI has already sent down a struct scsi_cmnd
558          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
559          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
560          * format with transport_generic_map_mem_to_cmd().
561          *
562          * We now tell TCM to add this WRITE CDB directly into the TCM storage
563          * object execution queue.
564          */
565         target_execute_cmd(se_cmd);
566         return 0;
567 }
568
569 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
570 {
571         return 0;
572 }
573
574 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
575 {
576         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
577                                 struct tcm_loop_cmd, tl_se_cmd);
578         struct scsi_cmnd *sc = tl_cmd->sc;
579
580         pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
581                  __func__, sc, sc->cmnd[0]);
582
583         sc->result = SAM_STAT_GOOD;
584         set_host_byte(sc, DID_OK);
585         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
586             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
587                 scsi_set_resid(sc, se_cmd->residual_count);
588         sc->scsi_done(sc);
589         return 0;
590 }
591
592 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
593 {
594         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
595                                 struct tcm_loop_cmd, tl_se_cmd);
596         struct scsi_cmnd *sc = tl_cmd->sc;
597
598         pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
599                  __func__, sc, sc->cmnd[0]);
600
601         if (se_cmd->sense_buffer &&
602            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
603             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
604
605                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
606                                 SCSI_SENSE_BUFFERSIZE);
607                 sc->result = SAM_STAT_CHECK_CONDITION;
608                 set_driver_byte(sc, DRIVER_SENSE);
609         } else
610                 sc->result = se_cmd->scsi_status;
611
612         set_host_byte(sc, DID_OK);
613         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
614             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
615                 scsi_set_resid(sc, se_cmd->residual_count);
616         sc->scsi_done(sc);
617         return 0;
618 }
619
620 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
621 {
622         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
623                                 struct tcm_loop_cmd, tl_se_cmd);
624
625         /* Wake up tcm_loop_issue_tmr(). */
626         complete(&tl_cmd->tmr_done);
627 }
628
629 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
630 {
631         return;
632 }
633
634 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
635 {
636         switch (tl_hba->tl_proto_id) {
637         case SCSI_PROTOCOL_SAS:
638                 return "SAS";
639         case SCSI_PROTOCOL_FCP:
640                 return "FCP";
641         case SCSI_PROTOCOL_ISCSI:
642                 return "iSCSI";
643         default:
644                 break;
645         }
646
647         return "Unknown";
648 }
649
650 /* Start items for tcm_loop_port_cit */
651
652 static int tcm_loop_port_link(
653         struct se_portal_group *se_tpg,
654         struct se_lun *lun)
655 {
656         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
657                                 struct tcm_loop_tpg, tl_se_tpg);
658         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
659
660         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
661         /*
662          * Add Linux/SCSI struct scsi_device by HCTL
663          */
664         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
665
666         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
667         return 0;
668 }
669
670 static void tcm_loop_port_unlink(
671         struct se_portal_group *se_tpg,
672         struct se_lun *se_lun)
673 {
674         struct scsi_device *sd;
675         struct tcm_loop_hba *tl_hba;
676         struct tcm_loop_tpg *tl_tpg;
677
678         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
679         tl_hba = tl_tpg->tl_hba;
680
681         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
682                                 se_lun->unpacked_lun);
683         if (!sd) {
684                 pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n",
685                        0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
686                 return;
687         }
688         /*
689          * Remove Linux/SCSI struct scsi_device by HCTL
690          */
691         scsi_remove_device(sd);
692         scsi_device_put(sd);
693
694         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
695
696         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
697 }
698
699 /* End items for tcm_loop_port_cit */
700
701 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
702                 struct config_item *item, char *page)
703 {
704         struct se_portal_group *se_tpg = attrib_to_tpg(item);
705         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
706                                                    tl_se_tpg);
707
708         return sprintf(page, "%d\n", tl_tpg->tl_fabric_prot_type);
709 }
710
711 static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
712                 struct config_item *item, const char *page, size_t count)
713 {
714         struct se_portal_group *se_tpg = attrib_to_tpg(item);
715         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
716                                                    tl_se_tpg);
717         unsigned long val;
718         int ret = kstrtoul(page, 0, &val);
719
720         if (ret) {
721                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
722                 return ret;
723         }
724         if (val != 0 && val != 1 && val != 3) {
725                 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
726                 return -EINVAL;
727         }
728         tl_tpg->tl_fabric_prot_type = val;
729
730         return count;
731 }
732
733 CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
734
735 static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
736         &tcm_loop_tpg_attrib_attr_fabric_prot_type,
737         NULL,
738 };
739
740 /* Start items for tcm_loop_nexus_cit */
741
742 static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
743                                   struct se_session *se_sess, void *p)
744 {
745         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
746                                         struct tcm_loop_tpg, tl_se_tpg);
747
748         tl_tpg->tl_nexus = p;
749         return 0;
750 }
751
752 static int tcm_loop_make_nexus(
753         struct tcm_loop_tpg *tl_tpg,
754         const char *name)
755 {
756         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
757         struct tcm_loop_nexus *tl_nexus;
758         int ret;
759
760         if (tl_tpg->tl_nexus) {
761                 pr_debug("tl_tpg->tl_nexus already exists\n");
762                 return -EEXIST;
763         }
764
765         tl_nexus = kzalloc(sizeof(*tl_nexus), GFP_KERNEL);
766         if (!tl_nexus)
767                 return -ENOMEM;
768
769         tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0,
770                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
771                                         name, tl_nexus, tcm_loop_alloc_sess_cb);
772         if (IS_ERR(tl_nexus->se_sess)) {
773                 ret = PTR_ERR(tl_nexus->se_sess);
774                 kfree(tl_nexus);
775                 return ret;
776         }
777
778         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n",
779                  tcm_loop_dump_proto_id(tl_hba), name);
780         return 0;
781 }
782
783 static int tcm_loop_drop_nexus(
784         struct tcm_loop_tpg *tpg)
785 {
786         struct se_session *se_sess;
787         struct tcm_loop_nexus *tl_nexus;
788
789         tl_nexus = tpg->tl_nexus;
790         if (!tl_nexus)
791                 return -ENODEV;
792
793         se_sess = tl_nexus->se_sess;
794         if (!se_sess)
795                 return -ENODEV;
796
797         if (atomic_read(&tpg->tl_tpg_port_count)) {
798                 pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n",
799                        atomic_read(&tpg->tl_tpg_port_count));
800                 return -EPERM;
801         }
802
803         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
804                  tcm_loop_dump_proto_id(tpg->tl_hba),
805                  tl_nexus->se_sess->se_node_acl->initiatorname);
806         /*
807          * Release the SCSI I_T Nexus to the emulated Target Port
808          */
809         target_remove_session(se_sess);
810         tpg->tl_nexus = NULL;
811         kfree(tl_nexus);
812         return 0;
813 }
814
815 /* End items for tcm_loop_nexus_cit */
816
817 static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
818 {
819         struct se_portal_group *se_tpg = to_tpg(item);
820         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
821                         struct tcm_loop_tpg, tl_se_tpg);
822         struct tcm_loop_nexus *tl_nexus;
823         ssize_t ret;
824
825         tl_nexus = tl_tpg->tl_nexus;
826         if (!tl_nexus)
827                 return -ENODEV;
828
829         ret = snprintf(page, PAGE_SIZE, "%s\n",
830                 tl_nexus->se_sess->se_node_acl->initiatorname);
831
832         return ret;
833 }
834
835 static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
836                 const char *page, size_t count)
837 {
838         struct se_portal_group *se_tpg = to_tpg(item);
839         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
840                         struct tcm_loop_tpg, tl_se_tpg);
841         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
842         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
843         int ret;
844         /*
845          * Shutdown the active I_T nexus if 'NULL' is passed..
846          */
847         if (!strncmp(page, "NULL", 4)) {
848                 ret = tcm_loop_drop_nexus(tl_tpg);
849                 return (!ret) ? count : ret;
850         }
851         /*
852          * Otherwise make sure the passed virtual Initiator port WWN matches
853          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
854          * tcm_loop_make_nexus()
855          */
856         if (strlen(page) >= TL_WWN_ADDR_LEN) {
857                 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
858                        page, TL_WWN_ADDR_LEN);
859                 return -EINVAL;
860         }
861         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
862
863         ptr = strstr(i_port, "naa.");
864         if (ptr) {
865                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
866                         pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
867                                i_port, tcm_loop_dump_proto_id(tl_hba));
868                         return -EINVAL;
869                 }
870                 port_ptr = &i_port[0];
871                 goto check_newline;
872         }
873         ptr = strstr(i_port, "fc.");
874         if (ptr) {
875                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
876                         pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
877                                i_port, tcm_loop_dump_proto_id(tl_hba));
878                         return -EINVAL;
879                 }
880                 port_ptr = &i_port[3]; /* Skip over "fc." */
881                 goto check_newline;
882         }
883         ptr = strstr(i_port, "iqn.");
884         if (ptr) {
885                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
886                         pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
887                                i_port, tcm_loop_dump_proto_id(tl_hba));
888                         return -EINVAL;
889                 }
890                 port_ptr = &i_port[0];
891                 goto check_newline;
892         }
893         pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
894                i_port);
895         return -EINVAL;
896         /*
897          * Clear any trailing newline for the NAA WWN
898          */
899 check_newline:
900         if (i_port[strlen(i_port)-1] == '\n')
901                 i_port[strlen(i_port)-1] = '\0';
902
903         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
904         if (ret < 0)
905                 return ret;
906
907         return count;
908 }
909
910 static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
911                 char *page)
912 {
913         struct se_portal_group *se_tpg = to_tpg(item);
914         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
915                         struct tcm_loop_tpg, tl_se_tpg);
916         const char *status = NULL;
917         ssize_t ret = -EINVAL;
918
919         switch (tl_tpg->tl_transport_status) {
920         case TCM_TRANSPORT_ONLINE:
921                 status = "online";
922                 break;
923         case TCM_TRANSPORT_OFFLINE:
924                 status = "offline";
925                 break;
926         default:
927                 break;
928         }
929
930         if (status)
931                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
932
933         return ret;
934 }
935
936 static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
937                 const char *page, size_t count)
938 {
939         struct se_portal_group *se_tpg = to_tpg(item);
940         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
941                         struct tcm_loop_tpg, tl_se_tpg);
942
943         if (!strncmp(page, "online", 6)) {
944                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
945                 return count;
946         }
947         if (!strncmp(page, "offline", 7)) {
948                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
949                 if (tl_tpg->tl_nexus) {
950                         struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
951
952                         core_allocate_nexus_loss_ua(tl_sess->se_node_acl);
953                 }
954                 return count;
955         }
956         return -EINVAL;
957 }
958
959 static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
960                                          char *page)
961 {
962         struct se_portal_group *se_tpg = to_tpg(item);
963         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
964                         struct tcm_loop_tpg, tl_se_tpg);
965         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
966
967         return snprintf(page, PAGE_SIZE, "%d:0:%d\n",
968                         tl_hba->sh->host_no, tl_tpg->tl_tpgt);
969 }
970
971 CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
972 CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
973 CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
974
975 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
976         &tcm_loop_tpg_attr_nexus,
977         &tcm_loop_tpg_attr_transport_status,
978         &tcm_loop_tpg_attr_address,
979         NULL,
980 };
981
982 /* Start items for tcm_loop_naa_cit */
983
984 static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn,
985                                                      const char *name)
986 {
987         struct tcm_loop_hba *tl_hba = container_of(wwn,
988                         struct tcm_loop_hba, tl_hba_wwn);
989         struct tcm_loop_tpg *tl_tpg;
990         int ret;
991         unsigned long tpgt;
992
993         if (strstr(name, "tpgt_") != name) {
994                 pr_err("Unable to locate \"tpgt_#\" directory group\n");
995                 return ERR_PTR(-EINVAL);
996         }
997         if (kstrtoul(name+5, 10, &tpgt))
998                 return ERR_PTR(-EINVAL);
999
1000         if (tpgt >= TL_TPGS_PER_HBA) {
1001                 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
1002                        tpgt, TL_TPGS_PER_HBA);
1003                 return ERR_PTR(-EINVAL);
1004         }
1005         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1006         tl_tpg->tl_hba = tl_hba;
1007         tl_tpg->tl_tpgt = tpgt;
1008         /*
1009          * Register the tl_tpg as a emulated TCM Target Endpoint
1010          */
1011         ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
1012         if (ret < 0)
1013                 return ERR_PTR(-ENOMEM);
1014
1015         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
1016                  tcm_loop_dump_proto_id(tl_hba),
1017                  config_item_name(&wwn->wwn_group.cg_item), tpgt);
1018         return &tl_tpg->tl_se_tpg;
1019 }
1020
1021 static void tcm_loop_drop_naa_tpg(
1022         struct se_portal_group *se_tpg)
1023 {
1024         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1025         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1026                                 struct tcm_loop_tpg, tl_se_tpg);
1027         struct tcm_loop_hba *tl_hba;
1028         unsigned short tpgt;
1029
1030         tl_hba = tl_tpg->tl_hba;
1031         tpgt = tl_tpg->tl_tpgt;
1032         /*
1033          * Release the I_T Nexus for the Virtual target link if present
1034          */
1035         tcm_loop_drop_nexus(tl_tpg);
1036         /*
1037          * Deregister the tl_tpg as a emulated TCM Target Endpoint
1038          */
1039         core_tpg_deregister(se_tpg);
1040
1041         tl_tpg->tl_hba = NULL;
1042         tl_tpg->tl_tpgt = 0;
1043
1044         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
1045                  tcm_loop_dump_proto_id(tl_hba),
1046                  config_item_name(&wwn->wwn_group.cg_item), tpgt);
1047 }
1048
1049 /* End items for tcm_loop_naa_cit */
1050
1051 /* Start items for tcm_loop_cit */
1052
1053 static struct se_wwn *tcm_loop_make_scsi_hba(
1054         struct target_fabric_configfs *tf,
1055         struct config_group *group,
1056         const char *name)
1057 {
1058         struct tcm_loop_hba *tl_hba;
1059         struct Scsi_Host *sh;
1060         char *ptr;
1061         int ret, off = 0;
1062
1063         tl_hba = kzalloc(sizeof(*tl_hba), GFP_KERNEL);
1064         if (!tl_hba)
1065                 return ERR_PTR(-ENOMEM);
1066
1067         /*
1068          * Determine the emulated Protocol Identifier and Target Port Name
1069          * based on the incoming configfs directory name.
1070          */
1071         ptr = strstr(name, "naa.");
1072         if (ptr) {
1073                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1074                 goto check_len;
1075         }
1076         ptr = strstr(name, "fc.");
1077         if (ptr) {
1078                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1079                 off = 3; /* Skip over "fc." */
1080                 goto check_len;
1081         }
1082         ptr = strstr(name, "iqn.");
1083         if (!ptr) {
1084                 pr_err("Unable to locate prefix for emulated Target Port: %s\n",
1085                        name);
1086                 ret = -EINVAL;
1087                 goto out;
1088         }
1089         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1090
1091 check_len:
1092         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1093                 pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
1094                        name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN);
1095                 ret = -EINVAL;
1096                 goto out;
1097         }
1098         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1099
1100         /*
1101          * Call device_register(tl_hba->dev) to register the emulated
1102          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1103          * device_register() callbacks in tcm_loop_driver_probe()
1104          */
1105         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1106         if (ret)
1107                 return ERR_PTR(ret);
1108
1109         sh = tl_hba->sh;
1110         tcm_loop_hba_no_cnt++;
1111         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1112                  tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1113         return &tl_hba->tl_hba_wwn;
1114 out:
1115         kfree(tl_hba);
1116         return ERR_PTR(ret);
1117 }
1118
1119 static void tcm_loop_drop_scsi_hba(
1120         struct se_wwn *wwn)
1121 {
1122         struct tcm_loop_hba *tl_hba = container_of(wwn,
1123                                 struct tcm_loop_hba, tl_hba_wwn);
1124
1125         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1126                  tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1127                  tl_hba->sh->host_no);
1128         /*
1129          * Call device_unregister() on the original tl_hba->dev.
1130          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1131          * release *tl_hba;
1132          */
1133         device_unregister(&tl_hba->dev);
1134 }
1135
1136 /* Start items for tcm_loop_cit */
1137 static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1138 {
1139         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1140 }
1141
1142 CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1143
1144 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1145         &tcm_loop_wwn_attr_version,
1146         NULL,
1147 };
1148
1149 /* End items for tcm_loop_cit */
1150
1151 static const struct target_core_fabric_ops loop_ops = {
1152         .module                         = THIS_MODULE,
1153         .name                           = "loopback",
1154         .get_fabric_name                = tcm_loop_get_fabric_name,
1155         .tpg_get_wwn                    = tcm_loop_get_endpoint_wwn,
1156         .tpg_get_tag                    = tcm_loop_get_tag,
1157         .tpg_check_demo_mode            = tcm_loop_check_demo_mode,
1158         .tpg_check_demo_mode_cache      = tcm_loop_check_demo_mode_cache,
1159         .tpg_check_demo_mode_write_protect =
1160                                 tcm_loop_check_demo_mode_write_protect,
1161         .tpg_check_prod_mode_write_protect =
1162                                 tcm_loop_check_prod_mode_write_protect,
1163         .tpg_check_prot_fabric_only     = tcm_loop_check_prot_fabric_only,
1164         .tpg_get_inst_index             = tcm_loop_get_inst_index,
1165         .check_stop_free                = tcm_loop_check_stop_free,
1166         .release_cmd                    = tcm_loop_release_cmd,
1167         .sess_get_index                 = tcm_loop_sess_get_index,
1168         .write_pending                  = tcm_loop_write_pending,
1169         .write_pending_status           = tcm_loop_write_pending_status,
1170         .set_default_node_attributes    = tcm_loop_set_default_node_attributes,
1171         .get_cmd_state                  = tcm_loop_get_cmd_state,
1172         .queue_data_in                  = tcm_loop_queue_data_in,
1173         .queue_status                   = tcm_loop_queue_status,
1174         .queue_tm_rsp                   = tcm_loop_queue_tm_rsp,
1175         .aborted_task                   = tcm_loop_aborted_task,
1176         .fabric_make_wwn                = tcm_loop_make_scsi_hba,
1177         .fabric_drop_wwn                = tcm_loop_drop_scsi_hba,
1178         .fabric_make_tpg                = tcm_loop_make_naa_tpg,
1179         .fabric_drop_tpg                = tcm_loop_drop_naa_tpg,
1180         .fabric_post_link               = tcm_loop_port_link,
1181         .fabric_pre_unlink              = tcm_loop_port_unlink,
1182         .tfc_wwn_attrs                  = tcm_loop_wwn_attrs,
1183         .tfc_tpg_base_attrs             = tcm_loop_tpg_attrs,
1184         .tfc_tpg_attrib_attrs           = tcm_loop_tpg_attrib_attrs,
1185 };
1186
1187 static int __init tcm_loop_fabric_init(void)
1188 {
1189         int ret = -ENOMEM;
1190
1191         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1192         if (!tcm_loop_workqueue)
1193                 goto out;
1194
1195         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1196                                 sizeof(struct tcm_loop_cmd),
1197                                 __alignof__(struct tcm_loop_cmd),
1198                                 0, NULL);
1199         if (!tcm_loop_cmd_cache) {
1200                 pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n");
1201                 goto out_destroy_workqueue;
1202         }
1203
1204         ret = tcm_loop_alloc_core_bus();
1205         if (ret)
1206                 goto out_destroy_cache;
1207
1208         ret = target_register_template(&loop_ops);
1209         if (ret)
1210                 goto out_release_core_bus;
1211
1212         return 0;
1213
1214 out_release_core_bus:
1215         tcm_loop_release_core_bus();
1216 out_destroy_cache:
1217         kmem_cache_destroy(tcm_loop_cmd_cache);
1218 out_destroy_workqueue:
1219         destroy_workqueue(tcm_loop_workqueue);
1220 out:
1221         return ret;
1222 }
1223
1224 static void __exit tcm_loop_fabric_exit(void)
1225 {
1226         target_unregister_template(&loop_ops);
1227         tcm_loop_release_core_bus();
1228         kmem_cache_destroy(tcm_loop_cmd_cache);
1229         destroy_workqueue(tcm_loop_workqueue);
1230 }
1231
1232 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1233 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1234 MODULE_LICENSE("GPL");
1235 module_init(tcm_loop_fabric_init);
1236 module_exit(tcm_loop_fabric_exit);