7ba2542aabe7cd1f8967fff942081e98c86fb21c
[linux-2.6.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 RisingTide Systems LLC.
7  *
8  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
9  *
10  * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  ****************************************************************************/
22
23 #include <linux/module.h>
24 #include <linux/moduleparam.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/types.h>
28 #include <linux/configfs.h>
29 #include <scsi/scsi.h>
30 #include <scsi/scsi_tcq.h>
31 #include <scsi/scsi_host.h>
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_cmnd.h>
34 #include <scsi/scsi_tcq.h>
35
36 #include <target/target_core_base.h>
37 #include <target/target_core_transport.h>
38 #include <target/target_core_fabric_ops.h>
39 #include <target/target_core_fabric_configfs.h>
40 #include <target/target_core_fabric_lib.h>
41 #include <target/target_core_configfs.h>
42 #include <target/target_core_device.h>
43 #include <target/target_core_tpg.h>
44 #include <target/target_core_tmr.h>
45
46 #include "tcm_loop.h"
47
48 #define to_tcm_loop_hba(hba)    container_of(hba, struct tcm_loop_hba, dev)
49
50 /* Local pointer to allocated TCM configfs fabric module */
51 static struct target_fabric_configfs *tcm_loop_fabric_configfs;
52
53 static struct kmem_cache *tcm_loop_cmd_cache;
54
55 static int tcm_loop_hba_no_cnt;
56
57 /*
58  * Allocate a tcm_loop cmd descriptor from target_core_mod code
59  *
60  * Can be called from interrupt context in tcm_loop_queuecommand() below
61  */
62 static struct se_cmd *tcm_loop_allocate_core_cmd(
63         struct tcm_loop_hba *tl_hba,
64         struct se_portal_group *se_tpg,
65         struct scsi_cmnd *sc)
66 {
67         struct se_cmd *se_cmd;
68         struct se_session *se_sess;
69         struct tcm_loop_nexus *tl_nexus = tl_hba->tl_nexus;
70         struct tcm_loop_cmd *tl_cmd;
71         int sam_task_attr;
72
73         if (!tl_nexus) {
74                 scmd_printk(KERN_ERR, sc, "TCM_Loop I_T Nexus"
75                                 " does not exist\n");
76                 set_host_byte(sc, DID_ERROR);
77                 return NULL;
78         }
79         se_sess = tl_nexus->se_sess;
80
81         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_ATOMIC);
82         if (!tl_cmd) {
83                 printk(KERN_ERR "Unable to allocate struct tcm_loop_cmd\n");
84                 set_host_byte(sc, DID_ERROR);
85                 return NULL;
86         }
87         se_cmd = &tl_cmd->tl_se_cmd;
88         /*
89          * Save the pointer to struct scsi_cmnd *sc
90          */
91         tl_cmd->sc = sc;
92         /*
93          * Locate the SAM Task Attr from struct scsi_cmnd *
94          */
95         if (sc->device->tagged_supported) {
96                 switch (sc->tag) {
97                 case HEAD_OF_QUEUE_TAG:
98                         sam_task_attr = MSG_HEAD_TAG;
99                         break;
100                 case ORDERED_QUEUE_TAG:
101                         sam_task_attr = MSG_ORDERED_TAG;
102                         break;
103                 default:
104                         sam_task_attr = MSG_SIMPLE_TAG;
105                         break;
106                 }
107         } else
108                 sam_task_attr = MSG_SIMPLE_TAG;
109
110         /*
111          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
112          */
113         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess,
114                         scsi_bufflen(sc), sc->sc_data_direction, sam_task_attr,
115                         &tl_cmd->tl_sense_buf[0]);
116
117         /*
118          * Signal BIDI usage with T_TASK(cmd)->t_tasks_bidi
119          */
120         if (scsi_bidi_cmnd(sc))
121                 se_cmd->t_tasks_bidi = 1;
122         /*
123          * Locate the struct se_lun pointer and attach it to struct se_cmd
124          */
125         if (transport_lookup_cmd_lun(se_cmd, tl_cmd->sc->device->lun) < 0) {
126                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
127                 set_host_byte(sc, DID_NO_CONNECT);
128                 return NULL;
129         }
130
131         return se_cmd;
132 }
133
134 /*
135  * Called by struct target_core_fabric_ops->new_cmd_map()
136  *
137  * Always called in process context.  A non zero return value
138  * here will signal to handle an exception based on the return code.
139  */
140 static int tcm_loop_new_cmd_map(struct se_cmd *se_cmd)
141 {
142         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
143                                 struct tcm_loop_cmd, tl_se_cmd);
144         struct scsi_cmnd *sc = tl_cmd->sc;
145         struct scatterlist *sgl_bidi = NULL;
146         u32 sgl_bidi_count = 0;
147         int ret;
148         /*
149          * Allocate the necessary tasks to complete the received CDB+data
150          */
151         ret = transport_generic_allocate_tasks(se_cmd, sc->cmnd);
152         if (ret == -ENOMEM) {
153                 /* Out of Resources */
154                 return PYX_TRANSPORT_LU_COMM_FAILURE;
155         } else if (ret == -EINVAL) {
156                 /*
157                  * Handle case for SAM_STAT_RESERVATION_CONFLICT
158                  */
159                 if (se_cmd->se_cmd_flags & SCF_SCSI_RESERVATION_CONFLICT)
160                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
161                 /*
162                  * Otherwise, return SAM_STAT_CHECK_CONDITION and return
163                  * sense data.
164                  */
165                 return PYX_TRANSPORT_USE_SENSE_REASON;
166         }
167
168         /*
169          * For BIDI commands, pass in the extra READ buffer
170          * to transport_generic_map_mem_to_cmd() below..
171          */
172         if (se_cmd->t_tasks_bidi) {
173                 struct scsi_data_buffer *sdb = scsi_in(sc);
174
175                 sgl_bidi = sdb->table.sgl;
176                 sgl_bidi_count = sdb->table.nents;
177         }
178
179         /*
180          * Map the SG memory into struct se_mem->page linked list using the same
181          * physical memory at sg->page_link.
182          */
183         ret = transport_generic_map_mem_to_cmd(se_cmd, scsi_sglist(sc),
184                         scsi_sg_count(sc), sgl_bidi, sgl_bidi_count);
185         if (ret < 0)
186                 return PYX_TRANSPORT_LU_COMM_FAILURE;
187
188         return 0;
189 }
190
191 /*
192  * Called from struct target_core_fabric_ops->check_stop_free()
193  */
194 static void tcm_loop_check_stop_free(struct se_cmd *se_cmd)
195 {
196         /*
197          * Do not release struct se_cmd's containing a valid TMR
198          * pointer.  These will be released directly in tcm_loop_device_reset()
199          * with transport_generic_free_cmd().
200          */
201         if (se_cmd->se_tmr_req)
202                 return;
203         /*
204          * Release the struct se_cmd, which will make a callback to release
205          * struct tcm_loop_cmd * in tcm_loop_deallocate_core_cmd()
206          */
207         transport_generic_free_cmd(se_cmd, 0, 1, 0);
208 }
209
210 /*
211  * Called from struct target_core_fabric_ops->release_cmd_to_pool()
212  */
213 static void tcm_loop_deallocate_core_cmd(struct se_cmd *se_cmd)
214 {
215         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
216                                 struct tcm_loop_cmd, tl_se_cmd);
217
218         kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
219 }
220
221 static int tcm_loop_proc_info(struct Scsi_Host *host, char *buffer,
222                                 char **start, off_t offset,
223                                 int length, int inout)
224 {
225         return sprintf(buffer, "tcm_loop_proc_info()\n");
226 }
227
228 static int tcm_loop_driver_probe(struct device *);
229 static int tcm_loop_driver_remove(struct device *);
230
231 static int pseudo_lld_bus_match(struct device *dev,
232                                 struct device_driver *dev_driver)
233 {
234         return 1;
235 }
236
237 static struct bus_type tcm_loop_lld_bus = {
238         .name                   = "tcm_loop_bus",
239         .match                  = pseudo_lld_bus_match,
240         .probe                  = tcm_loop_driver_probe,
241         .remove                 = tcm_loop_driver_remove,
242 };
243
244 static struct device_driver tcm_loop_driverfs = {
245         .name                   = "tcm_loop",
246         .bus                    = &tcm_loop_lld_bus,
247 };
248 /*
249  * Used with root_device_register() in tcm_loop_alloc_core_bus() below
250  */
251 struct device *tcm_loop_primary;
252
253 /*
254  * Copied from drivers/scsi/libfc/fc_fcp.c:fc_change_queue_depth() and
255  * drivers/scsi/libiscsi.c:iscsi_change_queue_depth()
256  */
257 static int tcm_loop_change_queue_depth(
258         struct scsi_device *sdev,
259         int depth,
260         int reason)
261 {
262         switch (reason) {
263         case SCSI_QDEPTH_DEFAULT:
264                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
265                 break;
266         case SCSI_QDEPTH_QFULL:
267                 scsi_track_queue_full(sdev, depth);
268                 break;
269         case SCSI_QDEPTH_RAMP_UP:
270                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
271                 break;
272         default:
273                 return -EOPNOTSUPP;
274         }
275         return sdev->queue_depth;
276 }
277
278 /*
279  * Main entry point from struct scsi_host_template for incoming SCSI CDB+Data
280  * from Linux/SCSI subsystem for SCSI low level device drivers (LLDs)
281  */
282 static int tcm_loop_queuecommand(
283         struct Scsi_Host *sh,
284         struct scsi_cmnd *sc)
285 {
286         struct se_cmd *se_cmd;
287         struct se_portal_group *se_tpg;
288         struct tcm_loop_hba *tl_hba;
289         struct tcm_loop_tpg *tl_tpg;
290
291         TL_CDB_DEBUG("tcm_loop_queuecommand() %d:%d:%d:%d got CDB: 0x%02x"
292                 " scsi_buf_len: %u\n", sc->device->host->host_no,
293                 sc->device->id, sc->device->channel, sc->device->lun,
294                 sc->cmnd[0], scsi_bufflen(sc));
295         /*
296          * Locate the tcm_loop_hba_t pointer
297          */
298         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
299         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
300         se_tpg = &tl_tpg->tl_se_tpg;
301         /*
302          * Determine the SAM Task Attribute and allocate tl_cmd and
303          * tl_cmd->tl_se_cmd from TCM infrastructure
304          */
305         se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
306         if (!se_cmd) {
307                 sc->scsi_done(sc);
308                 return 0;
309         }
310         /*
311          * Queue up the newly allocated to be processed in TCM thread context.
312         */
313         transport_generic_handle_cdb_map(se_cmd);
314         return 0;
315 }
316
317 /*
318  * Called from SCSI EH process context to issue a LUN_RESET TMR
319  * to struct scsi_device
320  */
321 static int tcm_loop_device_reset(struct scsi_cmnd *sc)
322 {
323         struct se_cmd *se_cmd = NULL;
324         struct se_portal_group *se_tpg;
325         struct se_session *se_sess;
326         struct tcm_loop_cmd *tl_cmd = NULL;
327         struct tcm_loop_hba *tl_hba;
328         struct tcm_loop_nexus *tl_nexus;
329         struct tcm_loop_tmr *tl_tmr = NULL;
330         struct tcm_loop_tpg *tl_tpg;
331         int ret = FAILED;
332         /*
333          * Locate the tcm_loop_hba_t pointer
334          */
335         tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host);
336         /*
337          * Locate the tl_nexus and se_sess pointers
338          */
339         tl_nexus = tl_hba->tl_nexus;
340         if (!tl_nexus) {
341                 printk(KERN_ERR "Unable to perform device reset without"
342                                 " active I_T Nexus\n");
343                 return FAILED;
344         }
345         se_sess = tl_nexus->se_sess;
346         /*
347          * Locate the tl_tpg and se_tpg pointers from TargetID in sc->device->id
348          */
349         tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
350         se_tpg = &tl_tpg->tl_se_tpg;
351
352         tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
353         if (!tl_cmd) {
354                 printk(KERN_ERR "Unable to allocate memory for tl_cmd\n");
355                 return FAILED;
356         }
357
358         tl_tmr = kzalloc(sizeof(struct tcm_loop_tmr), GFP_KERNEL);
359         if (!tl_tmr) {
360                 printk(KERN_ERR "Unable to allocate memory for tl_tmr\n");
361                 goto release;
362         }
363         init_waitqueue_head(&tl_tmr->tl_tmr_wait);
364
365         se_cmd = &tl_cmd->tl_se_cmd;
366         /*
367          * Initialize struct se_cmd descriptor from target_core_mod infrastructure
368          */
369         transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
370                                 DMA_NONE, MSG_SIMPLE_TAG,
371                                 &tl_cmd->tl_sense_buf[0]);
372         /*
373          * Allocate the LUN_RESET TMR
374          */
375         se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, tl_tmr,
376                                 TMR_LUN_RESET);
377         if (IS_ERR(se_cmd->se_tmr_req))
378                 goto release;
379         /*
380          * Locate the underlying TCM struct se_lun from sc->device->lun
381          */
382         if (transport_lookup_tmr_lun(se_cmd, sc->device->lun) < 0)
383                 goto release;
384         /*
385          * Queue the TMR to TCM Core and sleep waiting for tcm_loop_queue_tm_rsp()
386          * to wake us up.
387          */
388         transport_generic_handle_tmr(se_cmd);
389         wait_event(tl_tmr->tl_tmr_wait, atomic_read(&tl_tmr->tmr_complete));
390         /*
391          * The TMR LUN_RESET has completed, check the response status and
392          * then release allocations.
393          */
394         ret = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ?
395                 SUCCESS : FAILED;
396 release:
397         if (se_cmd)
398                 transport_generic_free_cmd(se_cmd, 1, 1, 0);
399         else
400                 kmem_cache_free(tcm_loop_cmd_cache, tl_cmd);
401         kfree(tl_tmr);
402         return ret;
403 }
404
405 static int tcm_loop_slave_alloc(struct scsi_device *sd)
406 {
407         set_bit(QUEUE_FLAG_BIDI, &sd->request_queue->queue_flags);
408         return 0;
409 }
410
411 static int tcm_loop_slave_configure(struct scsi_device *sd)
412 {
413         return 0;
414 }
415
416 static struct scsi_host_template tcm_loop_driver_template = {
417         .proc_info              = tcm_loop_proc_info,
418         .proc_name              = "tcm_loopback",
419         .name                   = "TCM_Loopback",
420         .queuecommand           = tcm_loop_queuecommand,
421         .change_queue_depth     = tcm_loop_change_queue_depth,
422         .eh_device_reset_handler = tcm_loop_device_reset,
423         .can_queue              = TL_SCSI_CAN_QUEUE,
424         .this_id                = -1,
425         .sg_tablesize           = TL_SCSI_SG_TABLESIZE,
426         .cmd_per_lun            = TL_SCSI_CMD_PER_LUN,
427         .max_sectors            = TL_SCSI_MAX_SECTORS,
428         .use_clustering         = DISABLE_CLUSTERING,
429         .slave_alloc            = tcm_loop_slave_alloc,
430         .slave_configure        = tcm_loop_slave_configure,
431         .module                 = THIS_MODULE,
432 };
433
434 static int tcm_loop_driver_probe(struct device *dev)
435 {
436         struct tcm_loop_hba *tl_hba;
437         struct Scsi_Host *sh;
438         int error;
439
440         tl_hba = to_tcm_loop_hba(dev);
441
442         sh = scsi_host_alloc(&tcm_loop_driver_template,
443                         sizeof(struct tcm_loop_hba));
444         if (!sh) {
445                 printk(KERN_ERR "Unable to allocate struct scsi_host\n");
446                 return -ENODEV;
447         }
448         tl_hba->sh = sh;
449
450         /*
451          * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
452          */
453         *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
454         /*
455          * Setup single ID, Channel and LUN for now..
456          */
457         sh->max_id = 2;
458         sh->max_lun = 0;
459         sh->max_channel = 0;
460         sh->max_cmd_len = TL_SCSI_MAX_CMD_LEN;
461
462         error = scsi_add_host(sh, &tl_hba->dev);
463         if (error) {
464                 printk(KERN_ERR "%s: scsi_add_host failed\n", __func__);
465                 scsi_host_put(sh);
466                 return -ENODEV;
467         }
468         return 0;
469 }
470
471 static int tcm_loop_driver_remove(struct device *dev)
472 {
473         struct tcm_loop_hba *tl_hba;
474         struct Scsi_Host *sh;
475
476         tl_hba = to_tcm_loop_hba(dev);
477         sh = tl_hba->sh;
478
479         scsi_remove_host(sh);
480         scsi_host_put(sh);
481         return 0;
482 }
483
484 static void tcm_loop_release_adapter(struct device *dev)
485 {
486         struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
487
488         kfree(tl_hba);
489 }
490
491 /*
492  * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
493  */
494 static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
495 {
496         int ret;
497
498         tl_hba->dev.bus = &tcm_loop_lld_bus;
499         tl_hba->dev.parent = tcm_loop_primary;
500         tl_hba->dev.release = &tcm_loop_release_adapter;
501         dev_set_name(&tl_hba->dev, "tcm_loop_adapter_%d", tcm_loop_host_id);
502
503         ret = device_register(&tl_hba->dev);
504         if (ret) {
505                 printk(KERN_ERR "device_register() failed for"
506                                 " tl_hba->dev: %d\n", ret);
507                 return -ENODEV;
508         }
509
510         return 0;
511 }
512
513 /*
514  * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
515  * tcm_loop SCSI bus.
516  */
517 static int tcm_loop_alloc_core_bus(void)
518 {
519         int ret;
520
521         tcm_loop_primary = root_device_register("tcm_loop_0");
522         if (IS_ERR(tcm_loop_primary)) {
523                 printk(KERN_ERR "Unable to allocate tcm_loop_primary\n");
524                 return PTR_ERR(tcm_loop_primary);
525         }
526
527         ret = bus_register(&tcm_loop_lld_bus);
528         if (ret) {
529                 printk(KERN_ERR "bus_register() failed for tcm_loop_lld_bus\n");
530                 goto dev_unreg;
531         }
532
533         ret = driver_register(&tcm_loop_driverfs);
534         if (ret) {
535                 printk(KERN_ERR "driver_register() failed for"
536                                 "tcm_loop_driverfs\n");
537                 goto bus_unreg;
538         }
539
540         printk(KERN_INFO "Initialized TCM Loop Core Bus\n");
541         return ret;
542
543 bus_unreg:
544         bus_unregister(&tcm_loop_lld_bus);
545 dev_unreg:
546         root_device_unregister(tcm_loop_primary);
547         return ret;
548 }
549
550 static void tcm_loop_release_core_bus(void)
551 {
552         driver_unregister(&tcm_loop_driverfs);
553         bus_unregister(&tcm_loop_lld_bus);
554         root_device_unregister(tcm_loop_primary);
555
556         printk(KERN_INFO "Releasing TCM Loop Core BUS\n");
557 }
558
559 static char *tcm_loop_get_fabric_name(void)
560 {
561         return "loopback";
562 }
563
564 static u8 tcm_loop_get_fabric_proto_ident(struct se_portal_group *se_tpg)
565 {
566         struct tcm_loop_tpg *tl_tpg =
567                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
568         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
569         /*
570          * tl_proto_id is set at tcm_loop_configfs.c:tcm_loop_make_scsi_hba()
571          * time based on the protocol dependent prefix of the passed configfs group.
572          *
573          * Based upon tl_proto_id, TCM_Loop emulates the requested fabric
574          * ProtocolID using target_core_fabric_lib.c symbols.
575          */
576         switch (tl_hba->tl_proto_id) {
577         case SCSI_PROTOCOL_SAS:
578                 return sas_get_fabric_proto_ident(se_tpg);
579         case SCSI_PROTOCOL_FCP:
580                 return fc_get_fabric_proto_ident(se_tpg);
581         case SCSI_PROTOCOL_ISCSI:
582                 return iscsi_get_fabric_proto_ident(se_tpg);
583         default:
584                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
585                         " SAS emulation\n", tl_hba->tl_proto_id);
586                 break;
587         }
588
589         return sas_get_fabric_proto_ident(se_tpg);
590 }
591
592 static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
593 {
594         struct tcm_loop_tpg *tl_tpg =
595                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
596         /*
597          * Return the passed NAA identifier for the SAS Target Port
598          */
599         return &tl_tpg->tl_hba->tl_wwn_address[0];
600 }
601
602 static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
603 {
604         struct tcm_loop_tpg *tl_tpg =
605                 (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
606         /*
607          * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
608          * to represent the SCSI Target Port.
609          */
610         return tl_tpg->tl_tpgt;
611 }
612
613 static u32 tcm_loop_get_default_depth(struct se_portal_group *se_tpg)
614 {
615         return 1;
616 }
617
618 static u32 tcm_loop_get_pr_transport_id(
619         struct se_portal_group *se_tpg,
620         struct se_node_acl *se_nacl,
621         struct t10_pr_registration *pr_reg,
622         int *format_code,
623         unsigned char *buf)
624 {
625         struct tcm_loop_tpg *tl_tpg =
626                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
627         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
628
629         switch (tl_hba->tl_proto_id) {
630         case SCSI_PROTOCOL_SAS:
631                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
632                                         format_code, buf);
633         case SCSI_PROTOCOL_FCP:
634                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
635                                         format_code, buf);
636         case SCSI_PROTOCOL_ISCSI:
637                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
638                                         format_code, buf);
639         default:
640                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
641                         " SAS emulation\n", tl_hba->tl_proto_id);
642                 break;
643         }
644
645         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
646                         format_code, buf);
647 }
648
649 static u32 tcm_loop_get_pr_transport_id_len(
650         struct se_portal_group *se_tpg,
651         struct se_node_acl *se_nacl,
652         struct t10_pr_registration *pr_reg,
653         int *format_code)
654 {
655         struct tcm_loop_tpg *tl_tpg =
656                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
657         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
658
659         switch (tl_hba->tl_proto_id) {
660         case SCSI_PROTOCOL_SAS:
661                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
662                                         format_code);
663         case SCSI_PROTOCOL_FCP:
664                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
665                                         format_code);
666         case SCSI_PROTOCOL_ISCSI:
667                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
668                                         format_code);
669         default:
670                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
671                         " SAS emulation\n", tl_hba->tl_proto_id);
672                 break;
673         }
674
675         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
676                         format_code);
677 }
678
679 /*
680  * Used for handling SCSI fabric dependent TransportIDs in SPC-3 and above
681  * Persistent Reservation SPEC_I_PT=1 and PROUT REGISTER_AND_MOVE operations.
682  */
683 static char *tcm_loop_parse_pr_out_transport_id(
684         struct se_portal_group *se_tpg,
685         const char *buf,
686         u32 *out_tid_len,
687         char **port_nexus_ptr)
688 {
689         struct tcm_loop_tpg *tl_tpg =
690                         (struct tcm_loop_tpg *)se_tpg->se_tpg_fabric_ptr;
691         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
692
693         switch (tl_hba->tl_proto_id) {
694         case SCSI_PROTOCOL_SAS:
695                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
696                                         port_nexus_ptr);
697         case SCSI_PROTOCOL_FCP:
698                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
699                                         port_nexus_ptr);
700         case SCSI_PROTOCOL_ISCSI:
701                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
702                                         port_nexus_ptr);
703         default:
704                 printk(KERN_ERR "Unknown tl_proto_id: 0x%02x, using"
705                         " SAS emulation\n", tl_hba->tl_proto_id);
706                 break;
707         }
708
709         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
710                         port_nexus_ptr);
711 }
712
713 /*
714  * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
715  * based upon the incoming fabric dependent SCSI Initiator Port
716  */
717 static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
718 {
719         return 1;
720 }
721
722 static int tcm_loop_check_demo_mode_cache(struct se_portal_group *se_tpg)
723 {
724         return 0;
725 }
726
727 /*
728  * Allow I_T Nexus full READ-WRITE access without explict Initiator Node ACLs for
729  * local virtual Linux/SCSI LLD passthrough into VM hypervisor guest
730  */
731 static int tcm_loop_check_demo_mode_write_protect(struct se_portal_group *se_tpg)
732 {
733         return 0;
734 }
735
736 /*
737  * Because TCM_Loop does not use explict ACLs and MappedLUNs, this will
738  * never be called for TCM_Loop by target_core_fabric_configfs.c code.
739  * It has been added here as a nop for target_fabric_tf_ops_check()
740  */
741 static int tcm_loop_check_prod_mode_write_protect(struct se_portal_group *se_tpg)
742 {
743         return 0;
744 }
745
746 static struct se_node_acl *tcm_loop_tpg_alloc_fabric_acl(
747         struct se_portal_group *se_tpg)
748 {
749         struct tcm_loop_nacl *tl_nacl;
750
751         tl_nacl = kzalloc(sizeof(struct tcm_loop_nacl), GFP_KERNEL);
752         if (!tl_nacl) {
753                 printk(KERN_ERR "Unable to allocate struct tcm_loop_nacl\n");
754                 return NULL;
755         }
756
757         return &tl_nacl->se_node_acl;
758 }
759
760 static void tcm_loop_tpg_release_fabric_acl(
761         struct se_portal_group *se_tpg,
762         struct se_node_acl *se_nacl)
763 {
764         struct tcm_loop_nacl *tl_nacl = container_of(se_nacl,
765                                 struct tcm_loop_nacl, se_node_acl);
766
767         kfree(tl_nacl);
768 }
769
770 static u32 tcm_loop_get_inst_index(struct se_portal_group *se_tpg)
771 {
772         return 1;
773 }
774
775 static void tcm_loop_new_cmd_failure(struct se_cmd *se_cmd)
776 {
777         /*
778          * Since TCM_loop is already passing struct scatterlist data from
779          * struct scsi_cmnd, no more Linux/SCSI failure dependent state need
780          * to be handled here.
781          */
782         return;
783 }
784
785 static int tcm_loop_is_state_remove(struct se_cmd *se_cmd)
786 {
787         /*
788          * Assume struct scsi_cmnd is not in remove state..
789          */
790         return 0;
791 }
792
793 static int tcm_loop_sess_logged_in(struct se_session *se_sess)
794 {
795         /*
796          * Assume that TL Nexus is always active
797          */
798         return 1;
799 }
800
801 static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
802 {
803         return 1;
804 }
805
806 static void tcm_loop_set_default_node_attributes(struct se_node_acl *se_acl)
807 {
808         return;
809 }
810
811 static u32 tcm_loop_get_task_tag(struct se_cmd *se_cmd)
812 {
813         return 1;
814 }
815
816 static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
817 {
818         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
819                         struct tcm_loop_cmd, tl_se_cmd);
820
821         return tl_cmd->sc_cmd_state;
822 }
823
824 static int tcm_loop_shutdown_session(struct se_session *se_sess)
825 {
826         return 0;
827 }
828
829 static void tcm_loop_close_session(struct se_session *se_sess)
830 {
831         return;
832 };
833
834 static void tcm_loop_stop_session(
835         struct se_session *se_sess,
836         int sess_sleep,
837         int conn_sleep)
838 {
839         return;
840 }
841
842 static void tcm_loop_fall_back_to_erl0(struct se_session *se_sess)
843 {
844         return;
845 }
846
847 static int tcm_loop_write_pending(struct se_cmd *se_cmd)
848 {
849         /*
850          * Since Linux/SCSI has already sent down a struct scsi_cmnd
851          * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
852          * memory, and memory has already been mapped to struct se_cmd->t_mem_list
853          * format with transport_generic_map_mem_to_cmd().
854          *
855          * We now tell TCM to add this WRITE CDB directly into the TCM storage
856          * object execution queue.
857          */
858         transport_generic_process_write(se_cmd);
859         return 0;
860 }
861
862 static int tcm_loop_write_pending_status(struct se_cmd *se_cmd)
863 {
864         return 0;
865 }
866
867 static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
868 {
869         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
870                                 struct tcm_loop_cmd, tl_se_cmd);
871         struct scsi_cmnd *sc = tl_cmd->sc;
872
873         TL_CDB_DEBUG("tcm_loop_queue_data_in() called for scsi_cmnd: %p"
874                      " cdb: 0x%02x\n", sc, sc->cmnd[0]);
875
876         sc->result = SAM_STAT_GOOD;
877         set_host_byte(sc, DID_OK);
878         sc->scsi_done(sc);
879         return 0;
880 }
881
882 static int tcm_loop_queue_status(struct se_cmd *se_cmd)
883 {
884         struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
885                                 struct tcm_loop_cmd, tl_se_cmd);
886         struct scsi_cmnd *sc = tl_cmd->sc;
887
888         TL_CDB_DEBUG("tcm_loop_queue_status() called for scsi_cmnd: %p"
889                         " cdb: 0x%02x\n", sc, sc->cmnd[0]);
890
891         if (se_cmd->sense_buffer &&
892            ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
893             (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
894
895                 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
896                                 SCSI_SENSE_BUFFERSIZE);
897                 sc->result = SAM_STAT_CHECK_CONDITION;
898                 set_driver_byte(sc, DRIVER_SENSE);
899         } else
900                 sc->result = se_cmd->scsi_status;
901
902         set_host_byte(sc, DID_OK);
903         sc->scsi_done(sc);
904         return 0;
905 }
906
907 static int tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
908 {
909         struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
910         struct tcm_loop_tmr *tl_tmr = se_tmr->fabric_tmr_ptr;
911         /*
912          * The SCSI EH thread will be sleeping on se_tmr->tl_tmr_wait, go ahead
913          * and wake up the wait_queue_head_t in tcm_loop_device_reset()
914          */
915         atomic_set(&tl_tmr->tmr_complete, 1);
916         wake_up(&tl_tmr->tl_tmr_wait);
917         return 0;
918 }
919
920 static u16 tcm_loop_set_fabric_sense_len(struct se_cmd *se_cmd, u32 sense_length)
921 {
922         return 0;
923 }
924
925 static u16 tcm_loop_get_fabric_sense_len(void)
926 {
927         return 0;
928 }
929
930 static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
931 {
932         switch (tl_hba->tl_proto_id) {
933         case SCSI_PROTOCOL_SAS:
934                 return "SAS";
935         case SCSI_PROTOCOL_FCP:
936                 return "FCP";
937         case SCSI_PROTOCOL_ISCSI:
938                 return "iSCSI";
939         default:
940                 break;
941         }
942
943         return "Unknown";
944 }
945
946 /* Start items for tcm_loop_port_cit */
947
948 static int tcm_loop_port_link(
949         struct se_portal_group *se_tpg,
950         struct se_lun *lun)
951 {
952         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
953                                 struct tcm_loop_tpg, tl_se_tpg);
954         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
955
956         atomic_inc(&tl_tpg->tl_tpg_port_count);
957         smp_mb__after_atomic_inc();
958         /*
959          * Add Linux/SCSI struct scsi_device by HCTL
960          */
961         scsi_add_device(tl_hba->sh, 0, tl_tpg->tl_tpgt, lun->unpacked_lun);
962
963         printk(KERN_INFO "TCM_Loop_ConfigFS: Port Link Successful\n");
964         return 0;
965 }
966
967 static void tcm_loop_port_unlink(
968         struct se_portal_group *se_tpg,
969         struct se_lun *se_lun)
970 {
971         struct scsi_device *sd;
972         struct tcm_loop_hba *tl_hba;
973         struct tcm_loop_tpg *tl_tpg;
974
975         tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
976         tl_hba = tl_tpg->tl_hba;
977
978         sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
979                                 se_lun->unpacked_lun);
980         if (!sd) {
981                 printk(KERN_ERR "Unable to locate struct scsi_device for %d:%d:"
982                         "%d\n", 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
983                 return;
984         }
985         /*
986          * Remove Linux/SCSI struct scsi_device by HCTL
987          */
988         scsi_remove_device(sd);
989         scsi_device_put(sd);
990
991         atomic_dec(&tl_tpg->tl_tpg_port_count);
992         smp_mb__after_atomic_dec();
993
994         printk(KERN_INFO "TCM_Loop_ConfigFS: Port Unlink Successful\n");
995 }
996
997 /* End items for tcm_loop_port_cit */
998
999 /* Start items for tcm_loop_nexus_cit */
1000
1001 static int tcm_loop_make_nexus(
1002         struct tcm_loop_tpg *tl_tpg,
1003         const char *name)
1004 {
1005         struct se_portal_group *se_tpg;
1006         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1007         struct tcm_loop_nexus *tl_nexus;
1008         int ret = -ENOMEM;
1009
1010         if (tl_tpg->tl_hba->tl_nexus) {
1011                 printk(KERN_INFO "tl_tpg->tl_hba->tl_nexus already exists\n");
1012                 return -EEXIST;
1013         }
1014         se_tpg = &tl_tpg->tl_se_tpg;
1015
1016         tl_nexus = kzalloc(sizeof(struct tcm_loop_nexus), GFP_KERNEL);
1017         if (!tl_nexus) {
1018                 printk(KERN_ERR "Unable to allocate struct tcm_loop_nexus\n");
1019                 return -ENOMEM;
1020         }
1021         /*
1022          * Initialize the struct se_session pointer
1023          */
1024         tl_nexus->se_sess = transport_init_session();
1025         if (IS_ERR(tl_nexus->se_sess)) {
1026                 ret = PTR_ERR(tl_nexus->se_sess);
1027                 goto out;
1028         }
1029         /*
1030          * Since we are running in 'demo mode' this call with generate a
1031          * struct se_node_acl for the tcm_loop struct se_portal_group with the SCSI
1032          * Initiator port name of the passed configfs group 'name'.
1033          */
1034         tl_nexus->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1035                                 se_tpg, (unsigned char *)name);
1036         if (!tl_nexus->se_sess->se_node_acl) {
1037                 transport_free_session(tl_nexus->se_sess);
1038                 goto out;
1039         }
1040         /*
1041          * Now, register the SAS I_T Nexus as active with the call to
1042          * transport_register_session()
1043          */
1044         __transport_register_session(se_tpg, tl_nexus->se_sess->se_node_acl,
1045                         tl_nexus->se_sess, tl_nexus);
1046         tl_tpg->tl_hba->tl_nexus = tl_nexus;
1047         printk(KERN_INFO "TCM_Loop_ConfigFS: Established I_T Nexus to emulated"
1048                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1049                 name);
1050         return 0;
1051
1052 out:
1053         kfree(tl_nexus);
1054         return ret;
1055 }
1056
1057 static int tcm_loop_drop_nexus(
1058         struct tcm_loop_tpg *tpg)
1059 {
1060         struct se_session *se_sess;
1061         struct tcm_loop_nexus *tl_nexus;
1062         struct tcm_loop_hba *tl_hba = tpg->tl_hba;
1063
1064         tl_nexus = tpg->tl_hba->tl_nexus;
1065         if (!tl_nexus)
1066                 return -ENODEV;
1067
1068         se_sess = tl_nexus->se_sess;
1069         if (!se_sess)
1070                 return -ENODEV;
1071
1072         if (atomic_read(&tpg->tl_tpg_port_count)) {
1073                 printk(KERN_ERR "Unable to remove TCM_Loop I_T Nexus with"
1074                         " active TPG port count: %d\n",
1075                         atomic_read(&tpg->tl_tpg_port_count));
1076                 return -EPERM;
1077         }
1078
1079         printk(KERN_INFO "TCM_Loop_ConfigFS: Removing I_T Nexus to emulated"
1080                 " %s Initiator Port: %s\n", tcm_loop_dump_proto_id(tl_hba),
1081                 tl_nexus->se_sess->se_node_acl->initiatorname);
1082         /*
1083          * Release the SCSI I_T Nexus to the emulated SAS Target Port
1084          */
1085         transport_deregister_session(tl_nexus->se_sess);
1086         tpg->tl_hba->tl_nexus = NULL;
1087         kfree(tl_nexus);
1088         return 0;
1089 }
1090
1091 /* End items for tcm_loop_nexus_cit */
1092
1093 static ssize_t tcm_loop_tpg_show_nexus(
1094         struct se_portal_group *se_tpg,
1095         char *page)
1096 {
1097         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1098                         struct tcm_loop_tpg, tl_se_tpg);
1099         struct tcm_loop_nexus *tl_nexus;
1100         ssize_t ret;
1101
1102         tl_nexus = tl_tpg->tl_hba->tl_nexus;
1103         if (!tl_nexus)
1104                 return -ENODEV;
1105
1106         ret = snprintf(page, PAGE_SIZE, "%s\n",
1107                 tl_nexus->se_sess->se_node_acl->initiatorname);
1108
1109         return ret;
1110 }
1111
1112 static ssize_t tcm_loop_tpg_store_nexus(
1113         struct se_portal_group *se_tpg,
1114         const char *page,
1115         size_t count)
1116 {
1117         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1118                         struct tcm_loop_tpg, tl_se_tpg);
1119         struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
1120         unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
1121         int ret;
1122         /*
1123          * Shutdown the active I_T nexus if 'NULL' is passed..
1124          */
1125         if (!strncmp(page, "NULL", 4)) {
1126                 ret = tcm_loop_drop_nexus(tl_tpg);
1127                 return (!ret) ? count : ret;
1128         }
1129         /*
1130          * Otherwise make sure the passed virtual Initiator port WWN matches
1131          * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
1132          * tcm_loop_make_nexus()
1133          */
1134         if (strlen(page) >= TL_WWN_ADDR_LEN) {
1135                 printk(KERN_ERR "Emulated NAA Sas Address: %s, exceeds"
1136                                 " max: %d\n", page, TL_WWN_ADDR_LEN);
1137                 return -EINVAL;
1138         }
1139         snprintf(&i_port[0], TL_WWN_ADDR_LEN, "%s", page);
1140
1141         ptr = strstr(i_port, "naa.");
1142         if (ptr) {
1143                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
1144                         printk(KERN_ERR "Passed SAS Initiator Port %s does not"
1145                                 " match target port protoid: %s\n", i_port,
1146                                 tcm_loop_dump_proto_id(tl_hba));
1147                         return -EINVAL;
1148                 }
1149                 port_ptr = &i_port[0];
1150                 goto check_newline;
1151         }
1152         ptr = strstr(i_port, "fc.");
1153         if (ptr) {
1154                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
1155                         printk(KERN_ERR "Passed FCP Initiator Port %s does not"
1156                                 " match target port protoid: %s\n", i_port,
1157                                 tcm_loop_dump_proto_id(tl_hba));
1158                         return -EINVAL;
1159                 }
1160                 port_ptr = &i_port[3]; /* Skip over "fc." */
1161                 goto check_newline;
1162         }
1163         ptr = strstr(i_port, "iqn.");
1164         if (ptr) {
1165                 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
1166                         printk(KERN_ERR "Passed iSCSI Initiator Port %s does not"
1167                                 " match target port protoid: %s\n", i_port,
1168                                 tcm_loop_dump_proto_id(tl_hba));
1169                         return -EINVAL;
1170                 }
1171                 port_ptr = &i_port[0];
1172                 goto check_newline;
1173         }
1174         printk(KERN_ERR "Unable to locate prefix for emulated Initiator Port:"
1175                         " %s\n", i_port);
1176         return -EINVAL;
1177         /*
1178          * Clear any trailing newline for the NAA WWN
1179          */
1180 check_newline:
1181         if (i_port[strlen(i_port)-1] == '\n')
1182                 i_port[strlen(i_port)-1] = '\0';
1183
1184         ret = tcm_loop_make_nexus(tl_tpg, port_ptr);
1185         if (ret < 0)
1186                 return ret;
1187
1188         return count;
1189 }
1190
1191 TF_TPG_BASE_ATTR(tcm_loop, nexus, S_IRUGO | S_IWUSR);
1192
1193 static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
1194         &tcm_loop_tpg_nexus.attr,
1195         NULL,
1196 };
1197
1198 /* Start items for tcm_loop_naa_cit */
1199
1200 struct se_portal_group *tcm_loop_make_naa_tpg(
1201         struct se_wwn *wwn,
1202         struct config_group *group,
1203         const char *name)
1204 {
1205         struct tcm_loop_hba *tl_hba = container_of(wwn,
1206                         struct tcm_loop_hba, tl_hba_wwn);
1207         struct tcm_loop_tpg *tl_tpg;
1208         char *tpgt_str, *end_ptr;
1209         int ret;
1210         unsigned short int tpgt;
1211
1212         tpgt_str = strstr(name, "tpgt_");
1213         if (!tpgt_str) {
1214                 printk(KERN_ERR "Unable to locate \"tpgt_#\" directory"
1215                                 " group\n");
1216                 return ERR_PTR(-EINVAL);
1217         }
1218         tpgt_str += 5; /* Skip ahead of "tpgt_" */
1219         tpgt = (unsigned short int) simple_strtoul(tpgt_str, &end_ptr, 0);
1220
1221         if (tpgt > TL_TPGS_PER_HBA) {
1222                 printk(KERN_ERR "Passed tpgt: %hu exceeds TL_TPGS_PER_HBA:"
1223                                 " %u\n", tpgt, TL_TPGS_PER_HBA);
1224                 return ERR_PTR(-EINVAL);
1225         }
1226         tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
1227         tl_tpg->tl_hba = tl_hba;
1228         tl_tpg->tl_tpgt = tpgt;
1229         /*
1230          * Register the tl_tpg as a emulated SAS TCM Target Endpoint
1231          */
1232         ret = core_tpg_register(&tcm_loop_fabric_configfs->tf_ops,
1233                         wwn, &tl_tpg->tl_se_tpg, tl_tpg,
1234                         TRANSPORT_TPG_TYPE_NORMAL);
1235         if (ret < 0)
1236                 return ERR_PTR(-ENOMEM);
1237
1238         printk(KERN_INFO "TCM_Loop_ConfigFS: Allocated Emulated %s"
1239                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1240                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1241
1242         return &tl_tpg->tl_se_tpg;
1243 }
1244
1245 void tcm_loop_drop_naa_tpg(
1246         struct se_portal_group *se_tpg)
1247 {
1248         struct se_wwn *wwn = se_tpg->se_tpg_wwn;
1249         struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
1250                                 struct tcm_loop_tpg, tl_se_tpg);
1251         struct tcm_loop_hba *tl_hba;
1252         unsigned short tpgt;
1253
1254         tl_hba = tl_tpg->tl_hba;
1255         tpgt = tl_tpg->tl_tpgt;
1256         /*
1257          * Release the I_T Nexus for the Virtual SAS link if present
1258          */
1259         tcm_loop_drop_nexus(tl_tpg);
1260         /*
1261          * Deregister the tl_tpg as a emulated SAS TCM Target Endpoint
1262          */
1263         core_tpg_deregister(se_tpg);
1264
1265         printk(KERN_INFO "TCM_Loop_ConfigFS: Deallocated Emulated %s"
1266                 " Target Port %s,t,0x%04x\n", tcm_loop_dump_proto_id(tl_hba),
1267                 config_item_name(&wwn->wwn_group.cg_item), tpgt);
1268 }
1269
1270 /* End items for tcm_loop_naa_cit */
1271
1272 /* Start items for tcm_loop_cit */
1273
1274 struct se_wwn *tcm_loop_make_scsi_hba(
1275         struct target_fabric_configfs *tf,
1276         struct config_group *group,
1277         const char *name)
1278 {
1279         struct tcm_loop_hba *tl_hba;
1280         struct Scsi_Host *sh;
1281         char *ptr;
1282         int ret, off = 0;
1283
1284         tl_hba = kzalloc(sizeof(struct tcm_loop_hba), GFP_KERNEL);
1285         if (!tl_hba) {
1286                 printk(KERN_ERR "Unable to allocate struct tcm_loop_hba\n");
1287                 return ERR_PTR(-ENOMEM);
1288         }
1289         /*
1290          * Determine the emulated Protocol Identifier and Target Port Name
1291          * based on the incoming configfs directory name.
1292          */
1293         ptr = strstr(name, "naa.");
1294         if (ptr) {
1295                 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1296                 goto check_len;
1297         }
1298         ptr = strstr(name, "fc.");
1299         if (ptr) {
1300                 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1301                 off = 3; /* Skip over "fc." */
1302                 goto check_len;
1303         }
1304         ptr = strstr(name, "iqn.");
1305         if (ptr) {
1306                 tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1307                 goto check_len;
1308         }
1309
1310         printk(KERN_ERR "Unable to locate prefix for emulated Target Port:"
1311                         " %s\n", name);
1312         return ERR_PTR(-EINVAL);
1313
1314 check_len:
1315         if (strlen(name) >= TL_WWN_ADDR_LEN) {
1316                 printk(KERN_ERR "Emulated NAA %s Address: %s, exceeds"
1317                         " max: %d\n", name, tcm_loop_dump_proto_id(tl_hba),
1318                         TL_WWN_ADDR_LEN);
1319                 kfree(tl_hba);
1320                 return ERR_PTR(-EINVAL);
1321         }
1322         snprintf(&tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, "%s", &name[off]);
1323
1324         /*
1325          * Call device_register(tl_hba->dev) to register the emulated
1326          * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1327          * device_register() callbacks in tcm_loop_driver_probe()
1328          */
1329         ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_hba_no_cnt);
1330         if (ret)
1331                 goto out;
1332
1333         sh = tl_hba->sh;
1334         tcm_loop_hba_no_cnt++;
1335         printk(KERN_INFO "TCM_Loop_ConfigFS: Allocated emulated Target"
1336                 " %s Address: %s at Linux/SCSI Host ID: %d\n",
1337                 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1338
1339         return &tl_hba->tl_hba_wwn;
1340 out:
1341         kfree(tl_hba);
1342         return ERR_PTR(ret);
1343 }
1344
1345 void tcm_loop_drop_scsi_hba(
1346         struct se_wwn *wwn)
1347 {
1348         struct tcm_loop_hba *tl_hba = container_of(wwn,
1349                                 struct tcm_loop_hba, tl_hba_wwn);
1350         int host_no = tl_hba->sh->host_no;
1351         /*
1352          * Call device_unregister() on the original tl_hba->dev.
1353          * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1354          * release *tl_hba;
1355          */
1356         device_unregister(&tl_hba->dev);
1357
1358         printk(KERN_INFO "TCM_Loop_ConfigFS: Deallocated emulated Target"
1359                 " SAS Address: %s at Linux/SCSI Host ID: %d\n",
1360                 config_item_name(&wwn->wwn_group.cg_item), host_no);
1361 }
1362
1363 /* Start items for tcm_loop_cit */
1364 static ssize_t tcm_loop_wwn_show_attr_version(
1365         struct target_fabric_configfs *tf,
1366         char *page)
1367 {
1368         return sprintf(page, "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1369 }
1370
1371 TF_WWN_ATTR_RO(tcm_loop, version);
1372
1373 static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1374         &tcm_loop_wwn_version.attr,
1375         NULL,
1376 };
1377
1378 /* End items for tcm_loop_cit */
1379
1380 static int tcm_loop_register_configfs(void)
1381 {
1382         struct target_fabric_configfs *fabric;
1383         struct config_group *tf_cg;
1384         int ret;
1385         /*
1386          * Set the TCM Loop HBA counter to zero
1387          */
1388         tcm_loop_hba_no_cnt = 0;
1389         /*
1390          * Register the top level struct config_item_type with TCM core
1391          */
1392         fabric = target_fabric_configfs_init(THIS_MODULE, "loopback");
1393         if (IS_ERR(fabric)) {
1394                 printk(KERN_ERR "tcm_loop_register_configfs() failed!\n");
1395                 return PTR_ERR(fabric);
1396         }
1397         /*
1398          * Setup the fabric API of function pointers used by target_core_mod
1399          */
1400         fabric->tf_ops.get_fabric_name = &tcm_loop_get_fabric_name;
1401         fabric->tf_ops.get_fabric_proto_ident = &tcm_loop_get_fabric_proto_ident;
1402         fabric->tf_ops.tpg_get_wwn = &tcm_loop_get_endpoint_wwn;
1403         fabric->tf_ops.tpg_get_tag = &tcm_loop_get_tag;
1404         fabric->tf_ops.tpg_get_default_depth = &tcm_loop_get_default_depth;
1405         fabric->tf_ops.tpg_get_pr_transport_id = &tcm_loop_get_pr_transport_id;
1406         fabric->tf_ops.tpg_get_pr_transport_id_len =
1407                                         &tcm_loop_get_pr_transport_id_len;
1408         fabric->tf_ops.tpg_parse_pr_out_transport_id =
1409                                         &tcm_loop_parse_pr_out_transport_id;
1410         fabric->tf_ops.tpg_check_demo_mode = &tcm_loop_check_demo_mode;
1411         fabric->tf_ops.tpg_check_demo_mode_cache =
1412                                         &tcm_loop_check_demo_mode_cache;
1413         fabric->tf_ops.tpg_check_demo_mode_write_protect =
1414                                         &tcm_loop_check_demo_mode_write_protect;
1415         fabric->tf_ops.tpg_check_prod_mode_write_protect =
1416                                         &tcm_loop_check_prod_mode_write_protect;
1417         /*
1418          * The TCM loopback fabric module runs in demo-mode to a local
1419          * virtual SCSI device, so fabric dependent initator ACLs are
1420          * not required.
1421          */
1422         fabric->tf_ops.tpg_alloc_fabric_acl = &tcm_loop_tpg_alloc_fabric_acl;
1423         fabric->tf_ops.tpg_release_fabric_acl =
1424                                         &tcm_loop_tpg_release_fabric_acl;
1425         fabric->tf_ops.tpg_get_inst_index = &tcm_loop_get_inst_index;
1426         /*
1427          * Used for setting up remaining TCM resources in process context
1428          */
1429         fabric->tf_ops.new_cmd_map = &tcm_loop_new_cmd_map;
1430         fabric->tf_ops.check_stop_free = &tcm_loop_check_stop_free;
1431         fabric->tf_ops.release_cmd_to_pool = &tcm_loop_deallocate_core_cmd;
1432         fabric->tf_ops.release_cmd_direct = &tcm_loop_deallocate_core_cmd;
1433         fabric->tf_ops.shutdown_session = &tcm_loop_shutdown_session;
1434         fabric->tf_ops.close_session = &tcm_loop_close_session;
1435         fabric->tf_ops.stop_session = &tcm_loop_stop_session;
1436         fabric->tf_ops.fall_back_to_erl0 = &tcm_loop_fall_back_to_erl0;
1437         fabric->tf_ops.sess_logged_in = &tcm_loop_sess_logged_in;
1438         fabric->tf_ops.sess_get_index = &tcm_loop_sess_get_index;
1439         fabric->tf_ops.sess_get_initiator_sid = NULL;
1440         fabric->tf_ops.write_pending = &tcm_loop_write_pending;
1441         fabric->tf_ops.write_pending_status = &tcm_loop_write_pending_status;
1442         /*
1443          * Not used for TCM loopback
1444          */
1445         fabric->tf_ops.set_default_node_attributes =
1446                                         &tcm_loop_set_default_node_attributes;
1447         fabric->tf_ops.get_task_tag = &tcm_loop_get_task_tag;
1448         fabric->tf_ops.get_cmd_state = &tcm_loop_get_cmd_state;
1449         fabric->tf_ops.new_cmd_failure = &tcm_loop_new_cmd_failure;
1450         fabric->tf_ops.queue_data_in = &tcm_loop_queue_data_in;
1451         fabric->tf_ops.queue_status = &tcm_loop_queue_status;
1452         fabric->tf_ops.queue_tm_rsp = &tcm_loop_queue_tm_rsp;
1453         fabric->tf_ops.set_fabric_sense_len = &tcm_loop_set_fabric_sense_len;
1454         fabric->tf_ops.get_fabric_sense_len = &tcm_loop_get_fabric_sense_len;
1455         fabric->tf_ops.is_state_remove = &tcm_loop_is_state_remove;
1456
1457         tf_cg = &fabric->tf_group;
1458         /*
1459          * Setup function pointers for generic logic in target_core_fabric_configfs.c
1460          */
1461         fabric->tf_ops.fabric_make_wwn = &tcm_loop_make_scsi_hba;
1462         fabric->tf_ops.fabric_drop_wwn = &tcm_loop_drop_scsi_hba;
1463         fabric->tf_ops.fabric_make_tpg = &tcm_loop_make_naa_tpg;
1464         fabric->tf_ops.fabric_drop_tpg = &tcm_loop_drop_naa_tpg;
1465         /*
1466          * fabric_post_link() and fabric_pre_unlink() are used for
1467          * registration and release of TCM Loop Virtual SCSI LUNs.
1468          */
1469         fabric->tf_ops.fabric_post_link = &tcm_loop_port_link;
1470         fabric->tf_ops.fabric_pre_unlink = &tcm_loop_port_unlink;
1471         fabric->tf_ops.fabric_make_np = NULL;
1472         fabric->tf_ops.fabric_drop_np = NULL;
1473         /*
1474          * Setup default attribute lists for various fabric->tf_cit_tmpl
1475          */
1476         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_loop_wwn_attrs;
1477         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_loop_tpg_attrs;
1478         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1479         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1480         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1481         /*
1482          * Once fabric->tf_ops has been setup, now register the fabric for
1483          * use within TCM
1484          */
1485         ret = target_fabric_configfs_register(fabric);
1486         if (ret < 0) {
1487                 printk(KERN_ERR "target_fabric_configfs_register() for"
1488                                 " TCM_Loop failed!\n");
1489                 target_fabric_configfs_free(fabric);
1490                 return -1;
1491         }
1492         /*
1493          * Setup our local pointer to *fabric.
1494          */
1495         tcm_loop_fabric_configfs = fabric;
1496         printk(KERN_INFO "TCM_LOOP[0] - Set fabric ->"
1497                         " tcm_loop_fabric_configfs\n");
1498         return 0;
1499 }
1500
1501 static void tcm_loop_deregister_configfs(void)
1502 {
1503         if (!tcm_loop_fabric_configfs)
1504                 return;
1505
1506         target_fabric_configfs_deregister(tcm_loop_fabric_configfs);
1507         tcm_loop_fabric_configfs = NULL;
1508         printk(KERN_INFO "TCM_LOOP[0] - Cleared"
1509                                 " tcm_loop_fabric_configfs\n");
1510 }
1511
1512 static int __init tcm_loop_fabric_init(void)
1513 {
1514         int ret;
1515
1516         tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1517                                 sizeof(struct tcm_loop_cmd),
1518                                 __alignof__(struct tcm_loop_cmd),
1519                                 0, NULL);
1520         if (!tcm_loop_cmd_cache) {
1521                 printk(KERN_ERR "kmem_cache_create() for"
1522                         " tcm_loop_cmd_cache failed\n");
1523                 return -ENOMEM;
1524         }
1525
1526         ret = tcm_loop_alloc_core_bus();
1527         if (ret)
1528                 return ret;
1529
1530         ret = tcm_loop_register_configfs();
1531         if (ret) {
1532                 tcm_loop_release_core_bus();
1533                 return ret;
1534         }
1535
1536         return 0;
1537 }
1538
1539 static void __exit tcm_loop_fabric_exit(void)
1540 {
1541         tcm_loop_deregister_configfs();
1542         tcm_loop_release_core_bus();
1543         kmem_cache_destroy(tcm_loop_cmd_cache);
1544 }
1545
1546 MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1547 MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1548 MODULE_LICENSE("GPL");
1549 module_init(tcm_loop_fabric_init);
1550 module_exit(tcm_loop_fabric_exit);