Merge branch 'pm-opp'
[pandora-kernel.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 #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 */
45 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
46
47 static struct workqueue_struct *tcm_loop_workqueue;
48 static struct kmem_cache *tcm_loop_cmd_cache;
49
50 static int tcm_loop_hba_no_cnt;
51
52 static int tcm_loop_queue_status(struct se_cmd *se_cmd);
53
54 /*
55  * Called from struct target_core_fabric_ops->check_stop_free()
56  */
57 static 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
74 static 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
82 static 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
88 static int tcm_loop_driver_probe(struct device *);
89 static int tcm_loop_driver_remove(struct device *);
90
91 static int pseudo_lld_bus_match(struct device *dev,
92                                 struct device_driver *dev_driver)
93 {
94         return 1;
95 }
96
97 static 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
104 static 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  */
111 struct device *tcm_loop_primary;
112
113 static void tcm_loop_submission_work(struct work_struct *work)
114 {
115         struct tcm_loop_cmd *tl_cmd =
116                 container_of(work, struct tcm_loop_cmd, work);
117         struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
118         struct scsi_cmnd *sc = tl_cmd->sc;
119         struct tcm_loop_nexus *tl_nexus;
120         struct tcm_loop_hba *tl_hba;
121         struct tcm_loop_tpg *tl_tpg;
122         struct scatterlist *sgl_bidi = NULL;
123         u32 sgl_bidi_count = 0, transfer_length;
124         int rc;
125
126         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
127         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
128
129         /*
130          * Ensure that this tl_tpg reference from the incoming sc->device->id
131          * has already been configured via tcm_loop_make_naa_tpg().
132          */
133         if (!tl_tpg->tl_hba) {
134                 set_host_byte(sc, DID_NO_CONNECT);
135                 goto out_done;
136         }
137         if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
138                 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
139                 goto out_done;
140         }
141         tl_nexus = tl_tpg->tl_nexus;
142         if (!tl_nexus) {
143                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
144                                 " does not exist\n");
145                 set_host_byte(sc, DID_ERROR);
146                 goto out_done;
147         }
148         if (scsi_bidi_cmnd(sc)) {
149                 struct scsi_data_buffer *sdb = scsi_in(sc);
150
151                 sgl_bidi = sdb->table.sgl;
152                 sgl_bidi_count = sdb->table.nents;
153                 se_cmd->se_cmd_flags |= SCF_BIDI;
154
155         }
156
157         transfer_length = scsi_transfer_length(sc);
158         if (!scsi_prot_sg_count(sc) &&
159             scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) {
160                 se_cmd->prot_pto = true;
161                 /*
162                  * loopback transport doesn't support
163                  * WRITE_GENERATE, READ_STRIP protection
164                  * information operations, go ahead unprotected.
165                  */
166                 transfer_length = scsi_bufflen(sc);
167         }
168
169         rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd,
170                         &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun,
171                         transfer_length, TCM_SIMPLE_TAG,
172                         sc->sc_data_direction, 0,
173                         scsi_sglist(sc), scsi_sg_count(sc),
174                         sgl_bidi, sgl_bidi_count,
175                         scsi_prot_sglist(sc), scsi_prot_sg_count(sc));
176         if (rc < 0) {
177                 set_host_byte(sc, DID_NO_CONNECT);
178                 goto out_done;
179         }
180         return;
181
182 out_done:
183         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
184         sc->scsi_done(sc);
185         return;
186 }
187
188 /*
189  * ->queuecommand can be and usually is called from interrupt context, so
190  * defer the actual submission to a workqueue.
191  */
192 static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
193 {
194         struct tcm_loop_cmd *tl_cmd;
195
196         pr_debug("tcm_loop_queuecommand() %d:%d:%d:%llu got CDB: 0x%02x"
197                 " scsi_buf_len: %u\n", sc->device->host->host_no,
198                 sc->device->id, sc->device->channel, sc->device->lun,
199                 sc->cmnd[0], scsi_bufflen(sc));
200
201         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
202         if (!tl_cmd) {
203                 pr_err("Unable to allocate struct tcm_loop_cmd\n");
204                 set_host_byte(sc, DID_ERROR);
205                 sc->scsi_done(sc);
206                 return 0;
207         }
208
209         tl_cmd->sc = sc;
210         tl_cmd->sc_cmd_tag = sc->request->tag;
211         INIT_WORK(&tl_cmd->work, tcm_loop_submission_work);
212         queue_work(tcm_loop_workqueue, &tl_cmd->work);
213         return 0;
214 }
215
216 /*
217  * Called from SCSI EH process context to issue a LUN_RESET TMR
218  * to struct scsi_device
219  */
220 static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
221                               int lun, int task, enum tcm_tmreq_table tmr)
222 {
223         struct se_cmd *se_cmd = NULL;
224         struct se_session *se_sess;
225         struct se_portal_group *se_tpg;
226         struct tcm_loop_nexus *tl_nexus;
227         struct tcm_loop_cmd *tl_cmd = NULL;
228         struct tcm_loop_tmr *tl_tmr = NULL;
229         int ret = TMR_FUNCTION_FAILED, rc;
230
231         /*
232          * Locate the tl_nexus and se_sess pointers
233          */
234         tl_nexus = tl_tpg->tl_nexus;
235         if (!tl_nexus) {
236                 pr_err("Unable to perform device reset without"
237                                 " active I_T Nexus\n");
238                 return ret;
239         }
240
241         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
242         if (!tl_cmd) {
243                 pr_err("Unable to allocate memory for tl_cmd\n");
244                 return ret;
245         }
246
247         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
248         if (!tl_tmr) {
249                 pr_err("Unable to allocate memory for tl_tmr\n");
250                 goto release;
251         }
252         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
253
254         se_cmd = &tl_cmd->tl_se_cmd;
255         se_tpg = &tl_tpg->tl_se_tpg;
256         se_sess = tl_tpg->tl_nexus->se_sess;
257         /*
258          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
259          */
260         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
261                                 DMA_NONE, TCM_SIMPLE_TAG,
262                                 &tl_cmd->tl_sense_buf[0]);
263
264         rc = core_tmr_alloc_req(se_cmd, tl_tmr, tmr, GFP_KERNEL);
265         if (rc < 0)
266                 goto release;
267
268         if (tmr == TMR_ABORT_TASK)
269                 se_cmd->se_tmr_req->ref_task_tag = task;
270
271         /*
272          * Locate the underlying TCM struct se_lun
273          */
274         if (transport_lookup_tmr_lun(se_cmd, lun) < 0) {
275                 ret = TMR_LUN_DOES_NOT_EXIST;
276                 goto release;
277         }
278         /*
279          * Queue the TMR to TCM Core and sleep waiting for
280          * tcm_loop_queue_tm_rsp() to wake us up.
281          */
282         transport_generic_handle_tmr(se_cmd);
283         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
284         /*
285          * The TMR LUN_RESET has completed, check the response status and
286          * then release allocations.
287          */
288         ret = se_cmd->se_tmr_req->response;
289 release:
290         if (se_cmd)
291                 transport_generic_free_cmd(se_cmd, 1);
292         else
293                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
294         kfree(tl_tmr);
295         return ret;
296 }
297
298 static int tcm_loop_abort_task(struct scsi_cmnd *sc)
299 {
300         struct tcm_loop_hba *tl_hba;
301         struct tcm_loop_tpg *tl_tpg;
302         int ret = FAILED;
303
304         /*
305          * Locate the tcm_loop_hba_t pointer
306          */
307         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
308         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
309         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
310                                  sc->request->tag, TMR_ABORT_TASK);
311         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
312 }
313
314 /*
315  * Called from SCSI EH process context to issue a LUN_RESET TMR
316  * to struct scsi_device
317  */
318 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
319 {
320         struct tcm_loop_hba *tl_hba;
321         struct tcm_loop_tpg *tl_tpg;
322         int ret = FAILED;
323
324         /*
325          * Locate the tcm_loop_hba_t pointer
326          */
327         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
328         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
329
330         ret = tcm_loop_issue_tmr(tl_tpg, sc->device->lun,
331                                  0, TMR_LUN_RESET);
332         return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
333 }
334
335 static int tcm_loop_target_reset(struct scsi_cmnd *sc)
336 {
337         struct tcm_loop_hba *tl_hba;
338         struct tcm_loop_tpg *tl_tpg;
339
340         /*
341          * Locate the tcm_loop_hba_t pointer
342          */
343         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
344         if (!tl_hba) {
345                 pr_err("Unable to perform device reset without"
346                                 " active I_T Nexus\n");
347                 return FAILED;
348         }
349         /*
350          * Locate the tl_tpg pointer from TargetID in sc->device->id
351          */
352         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
353         if (tl_tpg) {
354                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
355                 return SUCCESS;
356         }
357         return FAILED;
358 }
359
360 static int tcm_loop_slave_alloc(struct scsi_device *sd)
361 {
362         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
363         return 0;
364 }
365
366 static struct scsi_host_template tcm_loop_driver_template = {
367         .show_info              = tcm_loop_show_info,
368         .proc_name              = "tcm_loopback",
369         .name                   = "TCM_Loopback",
370         .queuecommand           = tcm_loop_queuecommand,
371         .change_queue_depth     = scsi_change_queue_depth,
372         .eh_abort_handler = tcm_loop_abort_task,
373         .eh_device_reset_handler = tcm_loop_device_reset,
374         .eh_target_reset_handler = tcm_loop_target_reset,
375         .can_queue              = 1024,
376         .this_id                = -1,
377         .sg_tablesize           = 256,
378         .cmd_per_lun            = 1024,
379         .max_sectors            = 0xFFFF,
380         .use_clustering         = DISABLE_CLUSTERING,
381         .slave_alloc            = tcm_loop_slave_alloc,
382         .module                 = THIS_MODULE,
383         .use_blk_tags           = 1,
384         .track_queue_depth      = 1,
385 };
386
387 static int tcm_loop_driver_probe(struct device *dev)
388 {
389         struct tcm_loop_hba *tl_hba;
390         struct Scsi_Host *sh;
391         int error, host_prot;
392
393         tl_hba = to_tcm_loop_hba(dev);
394
395         sh = scsi_host_alloc(&tcm_loop_driver_template,
396                         sizeof(struct tcm_loop_hba));
397         if (!sh) {
398                 pr_err("Unable to allocate struct scsi_host\n");
399                 return -ENODEV;
400         }
401         tl_hba->sh = sh;
402
403         /*
404          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
405          */
406         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
407         /*
408          * Setup single ID, Channel and LUN for now..
409          */
410         sh->max_id = 2;
411         sh->max_lun = 0;
412         sh->max_channel = 0;
413         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
414
415         host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
416                     SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
417                     SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
418
419         scsi_host_set_prot(sh, host_prot);
420         scsi_host_set_guard(sh, SHOST_DIX_GUARD_CRC);
421
422         error = scsi_add_host(sh, &tl_hba->dev);
423         if (error) {
424                 pr_err("%s: scsi_add_host failed\n", __func__);
425                 scsi_host_put(sh);
426                 return -ENODEV;
427         }
428         return 0;
429 }
430
431 static int tcm_loop_driver_remove(struct device *dev)
432 {
433         struct tcm_loop_hba *tl_hba;
434         struct Scsi_Host *sh;
435
436         tl_hba = to_tcm_loop_hba(dev);
437         sh = tl_hba->sh;
438
439         scsi_remove_host(sh);
440         scsi_host_put(sh);
441         return 0;
442 }
443
444 static void tcm_loop_release_adapter(struct device *dev)
445 {
446         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
447
448         kfree(tl_hba);
449 }
450
451 /*
452  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
453  */
454 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
455 {
456         int ret;
457
458         tl_hba->dev.bus = &tcm_loop_lld_bus;
459         tl_hba->dev.parent = tcm_loop_primary;
460         tl_hba->dev.release = &tcm_loop_release_adapter;
461         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
462
463         ret = device_register(&tl_hba->dev);
464         if (ret) {
465                 pr_err("device_register() failed for"
466                                 " tl_hba->dev: %d\n", ret);
467                 return -ENODEV;
468         }
469
470         return 0;
471 }
472
473 /*
474  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
475  * tcm_loop SCSI bus.
476  */
477 static int tcm_loop_alloc_core_bus(void)
478 {
479         int ret;
480
481         tcm_loop_primary = root_device_register("tcm_loop_0");
482         if (IS_ERR(tcm_loop_primary)) {
483                 pr_err("Unable to allocate tcm_loop_primary\n");
484                 return PTR_ERR(tcm_loop_primary);
485         }
486
487         ret = bus_register(&tcm_loop_lld_bus);
488         if (ret) {
489                 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
490                 goto dev_unreg;
491         }
492
493         ret = driver_register(&tcm_loop_driverfs);
494         if (ret) {
495                 pr_err("driver_register() failed for"
496                                 "tcm_loop_driverfs\n");
497                 goto bus_unreg;
498         }
499
500         pr_debug("Initialized TCM Loop Core Bus\n");
501         return ret;
502
503 bus_unreg:
504         bus_unregister(&tcm_loop_lld_bus);
505 dev_unreg:
506         root_device_unregister(tcm_loop_primary);
507         return ret;
508 }
509
510 static void tcm_loop_release_core_bus(void)
511 {
512         driver_unregister(&tcm_loop_driverfs);
513         bus_unregister(&tcm_loop_lld_bus);
514         root_device_unregister(tcm_loop_primary);
515
516         pr_debug("Releasing TCM Loop Core BUS\n");
517 }
518
519 static char *tcm_loop_get_fabric_name(void)
520 {
521         return "loopback";
522 }
523
524 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
525 {
526         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
527         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
528         /*
529          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
530          * time based on the protocol dependent prefix of the passed configfs group.
531          *
532          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
533          * ProtocolID using target_core_fabric_lib.c symbols.
534          */
535         switch (tl_hba->tl_proto_id) {
536         case SCSI_PROTOCOL_SAS:
537                 return sas_get_fabric_proto_ident(se_tpg);
538         case SCSI_PROTOCOL_FCP:
539                 return fc_get_fabric_proto_ident(se_tpg);
540         case SCSI_PROTOCOL_ISCSI:
541                 return iscsi_get_fabric_proto_ident(se_tpg);
542         default:
543                 pr_err("Unknown tl_proto_id: 0x%02x, using"
544                         " SAS emulation\n", tl_hba->tl_proto_id);
545                 break;
546         }
547
548         return sas_get_fabric_proto_ident(se_tpg);
549 }
550
551 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
552 {
553         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
554         /*
555          * Return the passed NAA identifier for the SAS Target Port
556          */
557         return &tl_tpg->tl_hba->tl_wwn_address[0];
558 }
559
560 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
561 {
562         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
563         /*
564          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
565          * to represent the SCSI Target Port.
566          */
567         return tl_tpg->tl_tpgt;
568 }
569
570 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
571 {
572         return 1;
573 }
574
575 static u32 tcm_loop_get_pr_transport_id(
576         struct se_portal_group *se_tpg,
577         struct se_node_acl *se_nacl,
578         struct t10_pr_registration *pr_reg,
579         int *format_code,
580         unsigned char *buf)
581 {
582         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
583         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
584
585         switch (tl_hba->tl_proto_id) {
586         case SCSI_PROTOCOL_SAS:
587                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
588                                         format_code, buf);
589         case SCSI_PROTOCOL_FCP:
590                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
591                                         format_code, buf);
592         case SCSI_PROTOCOL_ISCSI:
593                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
594                                         format_code, buf);
595         default:
596                 pr_err("Unknown tl_proto_id: 0x%02x, using"
597                         " SAS emulation\n", tl_hba->tl_proto_id);
598                 break;
599         }
600
601         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
602                         format_code, buf);
603 }
604
605 static u32 tcm_loop_get_pr_transport_id_len(
606         struct se_portal_group *se_tpg,
607         struct se_node_acl *se_nacl,
608         struct t10_pr_registration *pr_reg,
609         int *format_code)
610 {
611         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
612         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
613
614         switch (tl_hba->tl_proto_id) {
615         case SCSI_PROTOCOL_SAS:
616                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
617                                         format_code);
618         case SCSI_PROTOCOL_FCP:
619                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
620                                         format_code);
621         case SCSI_PROTOCOL_ISCSI:
622                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
623                                         format_code);
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_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
631                         format_code);
632 }
633
634 /*
635  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
636  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
637  */
638 static char *tcm_loop_parse_pr_out_transport_id(
639         struct se_portal_group *se_tpg,
640         const char *buf,
641         u32 *out_tid_len,
642         char **port_nexus_ptr)
643 {
644         struct tcm_loop_tpg *tl_tpg = se_tpg->se_tpg_fabric_ptr;
645         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
646
647         switch (tl_hba->tl_proto_id) {
648         case SCSI_PROTOCOL_SAS:
649                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
650                                         port_nexus_ptr);
651         case SCSI_PROTOCOL_FCP:
652                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
653                                         port_nexus_ptr);
654         case SCSI_PROTOCOL_ISCSI:
655                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
656                                         port_nexus_ptr);
657         default:
658                 pr_err("Unknown tl_proto_id: 0x%02x, using"
659                         " SAS emulation\n", tl_hba->tl_proto_id);
660                 break;
661         }
662
663         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
664                         port_nexus_ptr);
665 }
666
667 /*
668  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
669  * based upon the incoming fabric dependent SCSI Initiator Port
670  */
671 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
672 {
673         return 1;
674 }
675
676 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
677 {
678         return 0;
679 }
680
681 /*
682  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
683  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
684  */
685 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
686 {
687         return 0;
688 }
689
690 /*
691  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
692  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
693  * It has been added here as a nop for target_fabric_tf_ops_check()
694  */
695 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
696 {
697         return 0;
698 }
699
700 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
701         struct se_portal_group *se_tpg)
702 {
703         struct tcm_loop_nacl *tl_nacl;
704
705         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
706         if (!tl_nacl) {
707                 pr_err("Unable to allocate struct tcm_loop_nacl\n");
708                 return NULL;
709         }
710
711         return &tl_nacl->se_node_acl;
712 }
713
714 static void tcm_loop_tpg_release_fabric_acl(
715         struct se_portal_group *se_tpg,
716         struct se_node_acl *se_nacl)
717 {
718         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
719                                 struct tcm_loop_nacl, se_node_acl);
720
721         kfree(tl_nacl);
722 }
723
724 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
725 {
726         return 1;
727 }
728
729 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
730 {
731         return 1;
732 }
733
734 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
735 {
736         return;
737 }
738
739 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
740 {
741         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
742                         struct tcm_loop_cmd, tl_se_cmd);
743
744         return tl_cmd->sc_cmd_tag;
745 }
746
747 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
748 {
749         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
750                         struct tcm_loop_cmd, tl_se_cmd);
751
752         return tl_cmd->sc_cmd_state;
753 }
754
755 static int tcm_loop_shutdown_session(struct se_session *se_sess)
756 {
757         return 0;
758 }
759
760 static void tcm_loop_close_session(struct se_session *se_sess)
761 {
762         return;
763 };
764
765 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
766 {
767         /*
768          * Since Linux/SCSI has already sent down a struct scsi_cmnd
769          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
770          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
771          * format with transport_generic_map_mem_to_cmd().
772          *
773          * We now tell TCM to add this WRITE CDB directly into the TCM storage
774          * object execution queue.
775          */
776         target_execute_cmd(se_cmd);
777         return 0;
778 }
779
780 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
781 {
782         return 0;
783 }
784
785 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
786 {
787         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
788                                 struct tcm_loop_cmd, tl_se_cmd);
789         struct scsi_cmnd *sc = tl_cmd->sc;
790
791         pr_debug("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
792                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
793
794         sc->result = SAM_STAT_GOOD;
795         set_host_byte(sc, DID_OK);
796         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
797             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
798                 scsi_set_resid(sc, se_cmd->residual_count);
799         sc->scsi_done(sc);
800         return 0;
801 }
802
803 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
804 {
805         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
806                                 struct tcm_loop_cmd, tl_se_cmd);
807         struct scsi_cmnd *sc = tl_cmd->sc;
808
809         pr_debug("tcm_loop_queue_status() called for scsi_cmnd: %p"
810                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
811
812         if (se_cmd->sense_buffer &&
813            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
814             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
815
816                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
817                                 SCSI_SENSE_BUFFERSIZE);
818                 sc->result = SAM_STAT_CHECK_CONDITION;
819                 set_driver_byte(sc, DRIVER_SENSE);
820         } else
821                 sc->result = se_cmd->scsi_status;
822
823         set_host_byte(sc, DID_OK);
824         if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
825             (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
826                 scsi_set_resid(sc, se_cmd->residual_count);
827         sc->scsi_done(sc);
828         return 0;
829 }
830
831 static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
832 {
833         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
834         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
835         /*
836          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
837          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
838          */
839         atomic_set(&tl_tmr->tmr_complete, 1);
840         wake_up(&tl_tmr->tl_tmr_wait);
841 }
842
843 static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
844 {
845         return;
846 }
847
848 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
849 {
850         switch (tl_hba->tl_proto_id) {
851         case SCSI_PROTOCOL_SAS:
852                 return "SAS";
853         case SCSI_PROTOCOL_FCP:
854                 return "FCP";
855         case SCSI_PROTOCOL_ISCSI:
856                 return "iSCSI";
857         default:
858                 break;
859         }
860
861         return "Unknown";
862 }
863
864 /* Start items for tcm_loop_port_cit */
865
866 static int tcm_loop_port_link(
867         struct se_portal_group *se_tpg,
868         struct se_lun *lun)
869 {
870         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
871                                 struct tcm_loop_tpg, tl_se_tpg);
872         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
873
874         atomic_inc_mb(&tl_tpg->tl_tpg_port_count);
875         /*
876          * Add Linux/SCSI struct scsi_device by HCTL
877          */
878         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
879
880         pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
881         return 0;
882 }
883
884 static void tcm_loop_port_unlink(
885         struct se_portal_group *se_tpg,
886         struct se_lun *se_lun)
887 {
888         struct scsi_device *sd;
889         struct tcm_loop_hba *tl_hba;
890         struct tcm_loop_tpg *tl_tpg;
891
892         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
893         tl_hba = tl_tpg->tl_hba;
894
895         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
896                                 se_lun->unpacked_lun);
897         if (!sd) {
898                 pr_err("Unable to locate struct scsi_device for %d:%d:"
899                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
900                 return;
901         }
902         /*
903          * Remove Linux/SCSI struct scsi_device by HCTL
904          */
905         scsi_remove_device(sd);
906         scsi_device_put(sd);
907
908         atomic_dec_mb(&tl_tpg->tl_tpg_port_count);
909
910         pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
911 }
912
913 /* End items for tcm_loop_port_cit */
914
915 /* Start items for tcm_loop_nexus_cit */
916
917 static int tcm_loop_make_nexus(
918         struct tcm_loop_tpg *tl_tpg,
919         const char *name)
920 {
921         struct se_portal_group *se_tpg;
922         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
923         struct tcm_loop_nexus *tl_nexus;
924         int ret = -ENOMEM;
925
926         if (tl_tpg->tl_nexus) {
927                 pr_debug("tl_tpg->tl_nexus already exists\n");
928                 return -EEXIST;
929         }
930         se_tpg = &tl_tpg->tl_se_tpg;
931
932         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
933         if (!tl_nexus) {
934                 pr_err("Unable to allocate struct tcm_loop_nexus\n");
935                 return -ENOMEM;
936         }
937         /*
938          * Initialize the struct se_session pointer
939          */
940         tl_nexus->se_sess = transport_init_session(TARGET_PROT_ALL);
941         if (IS_ERR(tl_nexus->se_sess)) {
942                 ret = PTR_ERR(tl_nexus->se_sess);
943                 goto out;
944         }
945         /*
946          * Since we are running in 'demo mode' this call with generate a
947          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
948          * Initiator port name of the passed configfs group 'name'.
949          */
950         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
951                                 se_tpg, (unsigned char *)name);
952         if (!tl_nexus->se_sess->se_node_acl) {
953                 transport_free_session(tl_nexus->se_sess);
954                 goto out;
955         }
956         /*
957          * Now, register the SAS I_T Nexus as active with the call to
958          * transport_register_session()
959          */
960         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
961                         tl_nexus->se_sess, tl_nexus);
962         tl_tpg->tl_nexus = tl_nexus;
963         pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
964                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
965                 name);
966         return 0;
967
968 out:
969         kfree(tl_nexus);
970         return ret;
971 }
972
973 static int tcm_loop_drop_nexus(
974         struct tcm_loop_tpg *tpg)
975 {
976         struct se_session *se_sess;
977         struct tcm_loop_nexus *tl_nexus;
978
979         tl_nexus = tpg->tl_nexus;
980         if (!tl_nexus)
981                 return -ENODEV;
982
983         se_sess = tl_nexus->se_sess;
984         if (!se_sess)
985                 return -ENODEV;
986
987         if (atomic_read(&tpg->tl_tpg_port_count)) {
988                 pr_err("Unable to remove TCM_Loop I_T Nexus with"
989                         " active TPG port count: %d\n",
990                         atomic_read(&tpg->tl_tpg_port_count));
991                 return -EPERM;
992         }
993
994         pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
995                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tpg->tl_hba),
996                 tl_nexus->se_sess->se_node_acl->initiatorname);
997         /*
998          * Release the SCSI I_T Nexus to the emulated SAS Target Port
999          */
1000         transport_deregister_session(tl_nexus->se_sess);
1001         tpg->tl_nexus = NULL;
1002         kfree(tl_nexus);
1003         return 0;
1004 }
1005
1006 /* End items for tcm_loop_nexus_cit */
1007
1008 static ssize_t tcm_loop_tpg_show_nexus(
1009         struct se_portal_group *se_tpg,
1010         char *page)
1011 {
1012         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1013                         struct tcm_loop_tpg, tl_se_tpg);
1014         struct tcm_loop_nexus *tl_nexus;
1015         ssize_t ret;
1016
1017         tl_nexus = tl_tpg->tl_nexus;
1018         if (!tl_nexus)
1019                 return -ENODEV;
1020
1021         ret = snprintf(page, PAGE_SIZE, "%s\n",
1022                 tl_nexus->se_sess->se_node_acl->initiatorname);
1023
1024         return ret;
1025 }
1026
1027 static ssize_t tcm_loop_tpg_store_nexus(
1028         struct se_portal_group *se_tpg,
1029         const char *page,
1030         size_t count)
1031 {
1032         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1033                         struct tcm_loop_tpg, tl_se_tpg);
1034         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1035         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1036         int ret;
1037         /*
1038          * Shutdown the active I_T nexus if 'NULL' is passed..
1039          */
1040         if (!strncmp(page, "NULL", 4)) {
1041                 ret = tcm_loop_drop_nexus(tl_tpg);
1042                 return (!ret) ? count : ret;
1043         }
1044         /*
1045          * Otherwise make sure the passed virtual Initiator port WWN matches
1046          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1047          * tcm_loop_make_nexus()
1048          */
1049         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1050                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1051                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1052                 return -EINVAL;
1053         }
1054         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1055
1056         ptr = strstr(i_port, "naa.");
1057         if (ptr) {
1058                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1059                         pr_err("Passed SAS Initiator Port %s does not"
1060                                 " match target port protoid: %s\n", i_port,
1061                                 tcm_loop_dump_proto_id(tl_hba));
1062                         return -EINVAL;
1063                 }
1064                 port_ptr = &i_port[0];
1065                 goto check_newline;
1066         }
1067         ptr = strstr(i_port, "fc.");
1068         if (ptr) {
1069                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1070                         pr_err("Passed FCP Initiator Port %s does not"
1071                                 " match target port protoid: %s\n", i_port,
1072                                 tcm_loop_dump_proto_id(tl_hba));
1073                         return -EINVAL;
1074                 }
1075                 port_ptr = &i_port[3]; /* Skip over "fc." */
1076                 goto check_newline;
1077         }
1078         ptr = strstr(i_port, "iqn.");
1079         if (ptr) {
1080                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1081                         pr_err("Passed iSCSI Initiator Port %s does not"
1082                                 " match target port protoid: %s\n", i_port,
1083                                 tcm_loop_dump_proto_id(tl_hba));
1084                         return -EINVAL;
1085                 }
1086                 port_ptr = &i_port[0];
1087                 goto check_newline;
1088         }
1089         pr_err("Unable to locate prefix for emulated Initiator Port:"
1090                         " %s\n", i_port);
1091         return -EINVAL;
1092         /*
1093          * Clear any trailing newline for the NAA WWN
1094          */
1095 check_newline:
1096         if (i_port[strlen(i_port)-1] == '\n')
1097                 i_port[strlen(i_port)-1] = '\0';
1098
1099         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1100         if (ret < 0)
1101                 return ret;
1102
1103         return count;
1104 }
1105
1106 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1107
1108 static ssize_t tcm_loop_tpg_show_transport_status(
1109         struct se_portal_group *se_tpg,
1110         char *page)
1111 {
1112         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1113                         struct tcm_loop_tpg, tl_se_tpg);
1114         const char *status = NULL;
1115         ssize_t ret = -EINVAL;
1116
1117         switch (tl_tpg->tl_transport_status) {
1118         case TCM_TRANSPORT_ONLINE:
1119                 status = "online";
1120                 break;
1121         case TCM_TRANSPORT_OFFLINE:
1122                 status = "offline";
1123                 break;
1124         default:
1125                 break;
1126         }
1127
1128         if (status)
1129                 ret = snprintf(page, PAGE_SIZE, "%s\n", status);
1130
1131         return ret;
1132 }
1133
1134 static ssize_t tcm_loop_tpg_store_transport_status(
1135         struct se_portal_group *se_tpg,
1136         const char *page,
1137         size_t count)
1138 {
1139         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1140                         struct tcm_loop_tpg, tl_se_tpg);
1141
1142         if (!strncmp(page, "online", 6)) {
1143                 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
1144                 return count;
1145         }
1146         if (!strncmp(page, "offline", 7)) {
1147                 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
1148                 return count;
1149         }
1150         return -EINVAL;
1151 }
1152
1153 TF_TPG_BASE_ATTR(tcm_loop, transport_status, S_IRUGO | S_IWUSR);
1154
1155 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1156         &tcm_loop_tpg_nexus.attr,
1157         &tcm_loop_tpg_transport_status.attr,
1158         NULL,
1159 };
1160
1161 /* Start items for tcm_loop_naa_cit */
1162
1163 static struct se_portal_group *tcm_loop_make_naa_tpg(
1164         struct se_wwn *wwn,
1165         struct config_group *group,
1166         const char *name)
1167 {
1168         struct tcm_loop_hba *tl_hba = container_of(wwn,
1169                         struct tcm_loop_hba, tl_hba_wwn);
1170         struct tcm_loop_tpg *tl_tpg;
1171         char *tpgt_str, *end_ptr;
1172         int ret;
1173         unsigned short int tpgt;
1174
1175         tpgt_str = strstr(name, "tpgt_");
1176         if (!tpgt_str) {
1177                 pr_err("Unable to locate \"tpgt_#\" directory"
1178                                 " group\n");
1179                 return ERR_PTR(-EINVAL);
1180         }
1181         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1182         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1183
1184         if (tpgt >= TL_TPGS_PER_HBA) {
1185                 pr_err("Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1186                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1187                 return ERR_PTR(-EINVAL);
1188         }
1189         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1190         tl_tpg->tl_hba = tl_hba;
1191         tl_tpg->tl_tpgt = tpgt;
1192         /*
1193          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1194          */
1195         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1196                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1197                         TRANSPORT_TPG_TYPE_NORMAL);
1198         if (ret < 0)
1199                 return ERR_PTR(-ENOMEM);
1200
1201         pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s"
1202                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1203                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1204
1205         return &tl_tpg->tl_se_tpg;
1206 }
1207
1208 static void tcm_loop_drop_naa_tpg(
1209         struct se_portal_group *se_tpg)
1210 {
1211         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1212         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1213                                 struct tcm_loop_tpg, tl_se_tpg);
1214         struct tcm_loop_hba *tl_hba;
1215         unsigned short tpgt;
1216
1217         tl_hba = tl_tpg->tl_hba;
1218         tpgt = tl_tpg->tl_tpgt;
1219         /*
1220          * Release the I_T Nexus for the Virtual SAS link if present
1221          */
1222         tcm_loop_drop_nexus(tl_tpg);
1223         /*
1224          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1225          */
1226         core_tpg_deregister(se_tpg);
1227
1228         tl_tpg->tl_hba = NULL;
1229         tl_tpg->tl_tpgt = 0;
1230
1231         pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s"
1232                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1233                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1234 }
1235
1236 /* End items for tcm_loop_naa_cit */
1237
1238 /* Start items for tcm_loop_cit */
1239
1240 static struct se_wwn *tcm_loop_make_scsi_hba(
1241         struct target_fabric_configfs *tf,
1242         struct config_group *group,
1243         const char *name)
1244 {
1245         struct tcm_loop_hba *tl_hba;
1246         struct Scsi_Host *sh;
1247         char *ptr;
1248         int ret, off = 0;
1249
1250         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1251         if (!tl_hba) {
1252                 pr_err("Unable to allocate struct tcm_loop_hba\n");
1253                 return ERR_PTR(-ENOMEM);
1254         }
1255         /*
1256          * Determine the emulated Protocol Identifier and Target Port Name
1257          * based on the incoming configfs directory name.
1258          */
1259         ptr = strstr(name, "naa.");
1260         if (ptr) {
1261                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1262                 goto check_len;
1263         }
1264         ptr = strstr(name, "fc.");
1265         if (ptr) {
1266                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1267                 off = 3; /* Skip over "fc." */
1268                 goto check_len;
1269         }
1270         ptr = strstr(name, "iqn.");
1271         if (!ptr) {
1272                 pr_err("Unable to locate prefix for emulated Target "
1273                                 "Port: %s\n", name);
1274                 ret = -EINVAL;
1275                 goto out;
1276         }
1277         tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1278
1279 check_len:
1280         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1281                 pr_err("Emulated NAA %s Address: %s, exceeds"
1282                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1283                         TL_WWN_ADDR_LEN);
1284                 ret = -EINVAL;
1285                 goto out;
1286         }
1287         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1288
1289         /*
1290          * Call device_register(tl_hba->dev) to register the emulated
1291          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1292          * device_register() callbacks in tcm_loop_driver_probe()
1293          */
1294         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1295         if (ret)
1296                 goto out;
1297
1298         sh = tl_hba->sh;
1299         tcm_loop_hba_no_cnt++;
1300         pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target"
1301                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1302                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1303
1304         return &tl_hba->tl_hba_wwn;
1305 out:
1306         kfree(tl_hba);
1307         return ERR_PTR(ret);
1308 }
1309
1310 static void tcm_loop_drop_scsi_hba(
1311         struct se_wwn *wwn)
1312 {
1313         struct tcm_loop_hba *tl_hba = container_of(wwn,
1314                                 struct tcm_loop_hba, tl_hba_wwn);
1315
1316         pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target"
1317                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1318                 tl_hba->tl_wwn_address, tl_hba->sh->host_no);
1319         /*
1320          * Call device_unregister() on the original tl_hba->dev.
1321          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1322          * release *tl_hba;
1323          */
1324         device_unregister(&tl_hba->dev);
1325 }
1326
1327 /* Start items for tcm_loop_cit */
1328 static ssize_t tcm_loop_wwn_show_attr_version(
1329         struct target_fabric_configfs *tf,
1330         char *page)
1331 {
1332         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1333 }
1334
1335 TF_WWN_ATTR_RO(tcm_loop, version);
1336
1337 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1338         &tcm_loop_wwn_version.attr,
1339         NULL,
1340 };
1341
1342 /* End items for tcm_loop_cit */
1343
1344 static int tcm_loop_register_configfs(void)
1345 {
1346         struct target_fabric_configfs *fabric;
1347         int ret;
1348         /*
1349          * Set the TCM Loop HBA counter to zero
1350          */
1351         tcm_loop_hba_no_cnt = 0;
1352         /*
1353          * Register the top level struct config_item_type with TCM core
1354          */
1355         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1356         if (IS_ERR(fabric)) {
1357                 pr_err("tcm_loop_register_configfs() failed!\n");
1358                 return PTR_ERR(fabric);
1359         }
1360         /*
1361          * Setup the fabric API of function pointers used by target_core_mod
1362          */
1363         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1364         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1365         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1366         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1367         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1368         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1369         fabric->tf_ops.tpg_get_pr_transport_id_len =
1370                                         &tcm_loop_get_pr_transport_id_len;
1371         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1372                                         &tcm_loop_parse_pr_out_transport_id;
1373         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1374         fabric->tf_ops.tpg_check_demo_mode_cache =
1375                                         &tcm_loop_check_demo_mode_cache;
1376         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1377                                         &tcm_loop_check_demo_mode_write_protect;
1378         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1379                                         &tcm_loop_check_prod_mode_write_protect;
1380         /*
1381          * The TCM loopback fabric module runs in demo-mode to a local
1382          * virtual SCSI device, so fabric dependent initator ACLs are
1383          * not required.
1384          */
1385         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1386         fabric->tf_ops.tpg_release_fabric_acl =
1387                                         &tcm_loop_tpg_release_fabric_acl;
1388         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1389         /*
1390          * Used for setting up remaining TCM resources in process context
1391          */
1392         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1393         fabric->tf_ops.release_cmd = &tcm_loop_release_cmd;
1394         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1395         fabric->tf_ops.close_session = &tcm_loop_close_session;
1396         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1397         fabric->tf_ops.sess_get_initiator_sid = NULL;
1398         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1399         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1400         /*
1401          * Not used for TCM loopback
1402          */
1403         fabric->tf_ops.set_default_node_attributes =
1404                                         &tcm_loop_set_default_node_attributes;
1405         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1406         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1407         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1408         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1409         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1410         fabric->tf_ops.aborted_task = &tcm_loop_aborted_task;
1411
1412         /*
1413          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1414          */
1415         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1416         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1417         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1418         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1419         /*
1420          * fabric_post_link() and fabric_pre_unlink() are used for
1421          * registration and release of TCM Loop Virtual SCSI LUNs.
1422          */
1423         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1424         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1425         fabric->tf_ops.fabric_make_np = NULL;
1426         fabric->tf_ops.fabric_drop_np = NULL;
1427         /*
1428          * Setup default attribute lists for various fabric->tf_cit_tmpl
1429          */
1430         fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1431         fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1432         fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
1433         fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
1434         fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
1435         /*
1436          * Once fabric->tf_ops has been setup, now register the fabric for
1437          * use within TCM
1438          */
1439         ret = target_fabric_configfs_register(fabric);
1440         if (ret < 0) {
1441                 pr_err("target_fabric_configfs_register() for"
1442                                 " TCM_Loop failed!\n");
1443                 target_fabric_configfs_free(fabric);
1444                 return -1;
1445         }
1446         /*
1447          * Setup our local pointer to *fabric.
1448          */
1449         tcm_loop_fabric_configfs = fabric;
1450         pr_debug("TCM_LOOP[0] - Set fabric ->"
1451                         " tcm_loop_fabric_configfs\n");
1452         return 0;
1453 }
1454
1455 static void tcm_loop_deregister_configfs(void)
1456 {
1457         if (!tcm_loop_fabric_configfs)
1458                 return;
1459
1460         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1461         tcm_loop_fabric_configfs = NULL;
1462         pr_debug("TCM_LOOP[0] - Cleared"
1463                                 " tcm_loop_fabric_configfs\n");
1464 }
1465
1466 static int __init tcm_loop_fabric_init(void)
1467 {
1468         int ret = -ENOMEM;
1469
1470         tcm_loop_workqueue = alloc_workqueue("tcm_loop", 0, 0);
1471         if (!tcm_loop_workqueue)
1472                 goto out;
1473
1474         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1475                                 sizeof(struct tcm_loop_cmd),
1476                                 __alignof__(struct tcm_loop_cmd),
1477                                 0, NULL);
1478         if (!tcm_loop_cmd_cache) {
1479                 pr_debug("kmem_cache_create() for"
1480                         " tcm_loop_cmd_cache failed\n");
1481                 goto out_destroy_workqueue;
1482         }
1483
1484         ret = tcm_loop_alloc_core_bus();
1485         if (ret)
1486                 goto out_destroy_cache;
1487
1488         ret = tcm_loop_register_configfs();
1489         if (ret)
1490                 goto out_release_core_bus;
1491
1492         return 0;
1493
1494 out_release_core_bus:
1495         tcm_loop_release_core_bus();
1496 out_destroy_cache:
1497         kmem_cache_destroy(tcm_loop_cmd_cache);
1498 out_destroy_workqueue:
1499         destroy_workqueue(tcm_loop_workqueue);
1500 out:
1501         return ret;
1502 }
1503
1504 static void __exit tcm_loop_fabric_exit(void)
1505 {
1506         tcm_loop_deregister_configfs();
1507         tcm_loop_release_core_bus();
1508         kmem_cache_destroy(tcm_loop_cmd_cache);
1509         destroy_workqueue(tcm_loop_workqueue);
1510 }
1511
1512 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1513 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1514 MODULE_LICENSE("GPL");
1515 module_init(tcm_loop_fabric_init);
1516 module_exit(tcm_loop_fabric_exit);