1/*******************************************************************************
2 *
3 * This file contains the Linux/SCSI LLD virtual SCSI initiator driver
4 * for emulated SAS initiator ports
5 *
6 * © Copyright 2011-2013 Datera, Inc.
7 *
8 * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
9 *
10 * Author: Nicholas A. Bellinger <nab@risingtidesystems.com>
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 ****************************************************************************/
22
23#include <linux/module.h>
24#include <linux/moduleparam.h>
25#include <linux/init.h>
26#include <linux/slab.h>
27#include <linux/types.h>
28#include <linux/configfs.h>
29#include <scsi/scsi.h>
30#include <scsi/scsi_tcq.h>
31#include <scsi/scsi_host.h>
32#include <scsi/scsi_device.h>
33#include <scsi/scsi_cmnd.h>
34
35#include <target/target_core_base.h>
36#include <target/target_core_fabric.h>
37
38#include "tcm_loop.h"
39
40#define to_tcm_loop_hba(hba) container_of(hba, struct tcm_loop_hba, dev)
41
42static struct kmem_cache *tcm_loop_cmd_cache;
43
44static int tcm_loop_hba_no_cnt;
45
46static int tcm_loop_queue_status(struct se_cmd *se_cmd);
47
48static unsigned int tcm_loop_nr_hw_queues = 1;
49module_param_named(nr_hw_queues, tcm_loop_nr_hw_queues, uint, 0644);
50
51static unsigned int tcm_loop_can_queue = 1024;
52module_param_named(can_queue, tcm_loop_can_queue, uint, 0644);
53
54static unsigned int tcm_loop_cmd_per_lun = 1024;
55module_param_named(cmd_per_lun, tcm_loop_cmd_per_lun, uint, 0644);
56
57/*
58 * Called from struct target_core_fabric_ops->check_stop_free()
59 */
60static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
61{
62 return transport_generic_free_cmd(se_cmd, 0);
63}
64
65static void tcm_loop_release_cmd(struct se_cmd *se_cmd)
66{
67 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
68 struct tcm_loop_cmd, tl_se_cmd);
69 struct scsi_cmnd *sc = tl_cmd->sc;
70
71 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
72 kmem_cache_free(s: tcm_loop_cmd_cache, objp: tl_cmd);
73 else
74 scsi_done(cmd: sc);
75}
76
77static int tcm_loop_show_info(struct seq_file *m, struct Scsi_Host *host)
78{
79 seq_puts(m, s: "tcm_loop_proc_info()\n");
80 return 0;
81}
82
83static int tcm_loop_driver_probe(struct device *);
84static void tcm_loop_driver_remove(struct device *);
85
86static const struct bus_type tcm_loop_lld_bus = {
87 .name = "tcm_loop_bus",
88 .probe = tcm_loop_driver_probe,
89 .remove = tcm_loop_driver_remove,
90};
91
92static struct device_driver tcm_loop_driverfs = {
93 .name = "tcm_loop",
94 .bus = &tcm_loop_lld_bus,
95};
96/*
97 * Used with root_device_register() in tcm_loop_alloc_core_bus() below
98 */
99static struct device *tcm_loop_primary;
100
101static void tcm_loop_target_queue_cmd(struct tcm_loop_cmd *tl_cmd)
102{
103 struct se_cmd *se_cmd = &tl_cmd->tl_se_cmd;
104 struct scsi_cmnd *sc = tl_cmd->sc;
105 struct tcm_loop_nexus *tl_nexus;
106 struct tcm_loop_hba *tl_hba;
107 struct tcm_loop_tpg *tl_tpg;
108 struct scatterlist *sgl_bidi = NULL;
109 u32 sgl_bidi_count = 0, transfer_length;
110
111 tl_hba = *(struct tcm_loop_hba **)shost_priv(shost: sc->device->host);
112 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
113
114 /*
115 * Ensure that this tl_tpg reference from the incoming sc->device->id
116 * has already been configured via tcm_loop_make_naa_tpg().
117 */
118 if (!tl_tpg->tl_hba) {
119 set_host_byte(cmd: sc, status: DID_NO_CONNECT);
120 goto out_done;
121 }
122 if (tl_tpg->tl_transport_status == TCM_TRANSPORT_OFFLINE) {
123 set_host_byte(cmd: sc, status: DID_TRANSPORT_DISRUPTED);
124 goto out_done;
125 }
126 tl_nexus = tl_tpg->tl_nexus;
127 if (!tl_nexus) {
128 scmd_printk(KERN_ERR, sc,
129 "TCM_Loop I_T Nexus does not exist\n");
130 set_host_byte(cmd: sc, status: DID_ERROR);
131 goto out_done;
132 }
133
134 transfer_length = scsi_transfer_length(scmd: sc);
135 if (!scsi_prot_sg_count(cmd: sc) &&
136 scsi_get_prot_op(scmd: sc) != SCSI_PROT_NORMAL) {
137 se_cmd->prot_pto = true;
138 /*
139 * loopback transport doesn't support
140 * WRITE_GENERATE, READ_STRIP protection
141 * information operations, go ahead unprotected.
142 */
143 transfer_length = scsi_bufflen(cmd: sc);
144 }
145
146 se_cmd->tag = tl_cmd->sc_cmd_tag;
147 target_init_cmd(se_cmd, se_sess: tl_nexus->se_sess, sense: &tl_cmd->tl_sense_buf[0],
148 unpacked_lun: tl_cmd->sc->device->lun, data_length: transfer_length,
149 TCM_SIMPLE_TAG, data_dir: sc->sc_data_direction, flags: 0);
150
151 if (target_submit_prep(se_cmd, cdb: sc->cmnd, sgl: scsi_sglist(cmd: sc),
152 sgl_count: scsi_sg_count(cmd: sc), sgl_bidi, sgl_bidi_count,
153 sgl_prot: scsi_prot_sglist(cmd: sc), sgl_prot_count: scsi_prot_sg_count(cmd: sc),
154 GFP_ATOMIC))
155 return;
156
157 target_submit(se_cmd);
158 return;
159
160out_done:
161 scsi_done(cmd: sc);
162}
163
164/*
165 * ->queuecommand can be and usually is called from interrupt context, so
166 * defer the actual submission to a workqueue.
167 */
168static int tcm_loop_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
169{
170 struct tcm_loop_cmd *tl_cmd = scsi_cmd_priv(cmd: sc);
171
172 pr_debug("%s() %d:%d:%d:%llu got CDB: 0x%02x scsi_buf_len: %u\n",
173 __func__, sc->device->host->host_no, sc->device->id,
174 sc->device->channel, sc->device->lun, sc->cmnd[0],
175 scsi_bufflen(sc));
176
177 memset(tl_cmd, 0, sizeof(*tl_cmd));
178 tl_cmd->sc = sc;
179 tl_cmd->sc_cmd_tag = blk_mq_unique_tag(rq: scsi_cmd_to_rq(scmd: sc));
180
181 tcm_loop_target_queue_cmd(tl_cmd);
182 return 0;
183}
184
185/*
186 * Called from SCSI EH process context to issue a LUN_RESET TMR
187 * to struct scsi_device
188 */
189static int tcm_loop_issue_tmr(struct tcm_loop_tpg *tl_tpg,
190 u64 lun, int task, enum tcm_tmreq_table tmr)
191{
192 struct se_cmd *se_cmd;
193 struct se_session *se_sess;
194 struct tcm_loop_nexus *tl_nexus;
195 struct tcm_loop_cmd *tl_cmd;
196 int ret = TMR_FUNCTION_FAILED, rc;
197
198 /*
199 * Locate the tl_nexus and se_sess pointers
200 */
201 tl_nexus = tl_tpg->tl_nexus;
202 if (!tl_nexus) {
203 pr_err("Unable to perform device reset without active I_T Nexus\n");
204 return ret;
205 }
206
207 tl_cmd = kmem_cache_zalloc(tcm_loop_cmd_cache, GFP_KERNEL);
208 if (!tl_cmd)
209 return ret;
210
211 init_completion(x: &tl_cmd->tmr_done);
212
213 se_cmd = &tl_cmd->tl_se_cmd;
214 se_sess = tl_tpg->tl_nexus->se_sess;
215
216 rc = target_submit_tmr(se_cmd, se_sess, sense: tl_cmd->tl_sense_buf, unpacked_lun: lun,
217 NULL, tm_type: tmr, GFP_KERNEL, task,
218 TARGET_SCF_ACK_KREF);
219 if (rc < 0)
220 goto release;
221 wait_for_completion(&tl_cmd->tmr_done);
222 ret = se_cmd->se_tmr_req->response;
223 target_put_sess_cmd(se_cmd);
224
225out:
226 return ret;
227
228release:
229 kmem_cache_free(s: tcm_loop_cmd_cache, objp: tl_cmd);
230 goto out;
231}
232
233static int tcm_loop_abort_task(struct scsi_cmnd *sc)
234{
235 struct tcm_loop_hba *tl_hba;
236 struct tcm_loop_tpg *tl_tpg;
237 int ret;
238
239 /*
240 * Locate the tcm_loop_hba_t pointer
241 */
242 tl_hba = *(struct tcm_loop_hba **)shost_priv(shost: sc->device->host);
243 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
244 ret = tcm_loop_issue_tmr(tl_tpg, lun: sc->device->lun,
245 task: blk_mq_unique_tag(rq: scsi_cmd_to_rq(scmd: sc)),
246 tmr: TMR_ABORT_TASK);
247 return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
248}
249
250/*
251 * Called from SCSI EH process context to issue a LUN_RESET TMR
252 * to struct scsi_device
253 */
254static int tcm_loop_device_reset(struct scsi_cmnd *sc)
255{
256 struct tcm_loop_hba *tl_hba;
257 struct tcm_loop_tpg *tl_tpg;
258 int ret;
259
260 /*
261 * Locate the tcm_loop_hba_t pointer
262 */
263 tl_hba = *(struct tcm_loop_hba **)shost_priv(shost: sc->device->host);
264 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
265
266 ret = tcm_loop_issue_tmr(tl_tpg, lun: sc->device->lun,
267 task: 0, tmr: TMR_LUN_RESET);
268 return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
269}
270
271static int tcm_loop_target_reset(struct scsi_cmnd *sc)
272{
273 struct tcm_loop_hba *tl_hba;
274 struct tcm_loop_tpg *tl_tpg;
275
276 /*
277 * Locate the tcm_loop_hba_t pointer
278 */
279 tl_hba = *(struct tcm_loop_hba **)shost_priv(shost: sc->device->host);
280 if (!tl_hba) {
281 pr_err("Unable to perform device reset without active I_T Nexus\n");
282 return FAILED;
283 }
284 /*
285 * Locate the tl_tpg pointer from TargetID in sc->device->id
286 */
287 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
288 if (tl_tpg) {
289 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
290 return SUCCESS;
291 }
292 return FAILED;
293}
294
295static const struct scsi_host_template tcm_loop_driver_template = {
296 .show_info = tcm_loop_show_info,
297 .proc_name = "tcm_loopback",
298 .name = "TCM_Loopback",
299 .queuecommand = tcm_loop_queuecommand,
300 .change_queue_depth = scsi_change_queue_depth,
301 .eh_abort_handler = tcm_loop_abort_task,
302 .eh_device_reset_handler = tcm_loop_device_reset,
303 .eh_target_reset_handler = tcm_loop_target_reset,
304 .this_id = -1,
305 .sg_tablesize = 256,
306 .max_sectors = 0xFFFF,
307 .dma_boundary = PAGE_SIZE - 1,
308 .module = THIS_MODULE,
309 .track_queue_depth = 1,
310 .cmd_size = sizeof(struct tcm_loop_cmd),
311};
312
313static int tcm_loop_driver_probe(struct device *dev)
314{
315 struct tcm_loop_hba *tl_hba;
316 struct Scsi_Host *sh;
317 int error, host_prot;
318
319 tl_hba = to_tcm_loop_hba(dev);
320
321 sh = scsi_host_alloc(&tcm_loop_driver_template,
322 sizeof(struct tcm_loop_hba));
323 if (!sh) {
324 pr_err("Unable to allocate struct scsi_host\n");
325 return -ENODEV;
326 }
327 tl_hba->sh = sh;
328
329 /*
330 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
331 */
332 *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
333 /*
334 * Setup single ID, Channel and LUN for now..
335 */
336 sh->max_id = 2;
337 sh->max_lun = 0;
338 sh->max_channel = 0;
339 sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
340 sh->nr_hw_queues = tcm_loop_nr_hw_queues;
341 sh->can_queue = tcm_loop_can_queue;
342 sh->cmd_per_lun = tcm_loop_cmd_per_lun;
343
344 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
345 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
346 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
347
348 scsi_host_set_prot(shost: sh, mask: host_prot);
349 scsi_host_set_guard(shost: sh, type: SHOST_DIX_GUARD_CRC);
350
351 error = scsi_add_host(host: sh, dev: &tl_hba->dev);
352 if (error) {
353 pr_err("%s: scsi_add_host failed\n", __func__);
354 scsi_host_put(t: sh);
355 return -ENODEV;
356 }
357 return 0;
358}
359
360static void tcm_loop_driver_remove(struct device *dev)
361{
362 struct tcm_loop_hba *tl_hba;
363 struct Scsi_Host *sh;
364
365 tl_hba = to_tcm_loop_hba(dev);
366 sh = tl_hba->sh;
367
368 scsi_remove_host(sh);
369 scsi_host_put(t: sh);
370}
371
372static void tcm_loop_release_adapter(struct device *dev)
373{
374 struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
375
376 kfree(objp: tl_hba);
377}
378
379/*
380 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
381 */
382static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
383{
384 int ret;
385
386 tl_hba->dev.bus = &tcm_loop_lld_bus;
387 tl_hba->dev.parent = tcm_loop_primary;
388 tl_hba->dev.release = &tcm_loop_release_adapter;
389 dev_set_name(dev: &tl_hba->dev, name: "tcm_loop_adapter_%d", tcm_loop_host_id);
390
391 ret = device_register(dev: &tl_hba->dev);
392 if (ret) {
393 pr_err("device_register() failed for tl_hba->dev: %d\n", ret);
394 put_device(dev: &tl_hba->dev);
395 return -ENODEV;
396 }
397
398 return 0;
399}
400
401/*
402 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
403 * tcm_loop SCSI bus.
404 */
405static int tcm_loop_alloc_core_bus(void)
406{
407 int ret;
408
409 tcm_loop_primary = root_device_register("tcm_loop_0");
410 if (IS_ERR(ptr: tcm_loop_primary)) {
411 pr_err("Unable to allocate tcm_loop_primary\n");
412 return PTR_ERR(ptr: tcm_loop_primary);
413 }
414
415 ret = bus_register(bus: &tcm_loop_lld_bus);
416 if (ret) {
417 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
418 goto dev_unreg;
419 }
420
421 ret = driver_register(drv: &tcm_loop_driverfs);
422 if (ret) {
423 pr_err("driver_register() failed for tcm_loop_driverfs\n");
424 goto bus_unreg;
425 }
426
427 pr_debug("Initialized TCM Loop Core Bus\n");
428 return ret;
429
430bus_unreg:
431 bus_unregister(bus: &tcm_loop_lld_bus);
432dev_unreg:
433 root_device_unregister(root: tcm_loop_primary);
434 return ret;
435}
436
437static void tcm_loop_release_core_bus(void)
438{
439 driver_unregister(drv: &tcm_loop_driverfs);
440 bus_unregister(bus: &tcm_loop_lld_bus);
441 root_device_unregister(root: tcm_loop_primary);
442
443 pr_debug("Releasing TCM Loop Core BUS\n");
444}
445
446static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
447{
448 return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
449}
450
451static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
452{
453 /*
454 * Return the passed NAA identifier for the Target Port
455 */
456 return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
457}
458
459static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
460{
461 /*
462 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
463 * to represent the SCSI Target Port.
464 */
465 return tl_tpg(se_tpg)->tl_tpgt;
466}
467
468/*
469 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
470 * based upon the incoming fabric dependent SCSI Initiator Port
471 */
472static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
473{
474 return 1;
475}
476
477static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
478{
479 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
480 tl_se_tpg);
481 return tl_tpg->tl_fabric_prot_type;
482}
483
484static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
485{
486 return 1;
487}
488
489static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
490{
491 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
492 struct tcm_loop_cmd, tl_se_cmd);
493
494 return tl_cmd->sc_cmd_state;
495}
496
497static int tcm_loop_write_pending(struct se_cmd *se_cmd)
498{
499 /*
500 * Since Linux/SCSI has already sent down a struct scsi_cmnd
501 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
502 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
503 * format with transport_generic_map_mem_to_cmd().
504 *
505 * We now tell TCM to add this WRITE CDB directly into the TCM storage
506 * object execution queue.
507 */
508 target_execute_cmd(cmd: se_cmd);
509 return 0;
510}
511
512static int tcm_loop_queue_data_or_status(const char *func,
513 struct se_cmd *se_cmd, u8 scsi_status)
514{
515 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
516 struct tcm_loop_cmd, tl_se_cmd);
517 struct scsi_cmnd *sc = tl_cmd->sc;
518
519 pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
520 func, sc, sc->cmnd[0]);
521
522 if (se_cmd->sense_buffer &&
523 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
524 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
525
526 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
527 SCSI_SENSE_BUFFERSIZE);
528 sc->result = SAM_STAT_CHECK_CONDITION;
529 } else
530 sc->result = scsi_status;
531
532 set_host_byte(cmd: sc, status: DID_OK);
533 if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
534 (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
535 scsi_set_resid(cmd: sc, resid: se_cmd->residual_count);
536 return 0;
537}
538
539static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
540{
541 return tcm_loop_queue_data_or_status(func: __func__, se_cmd, scsi_status: SAM_STAT_GOOD);
542}
543
544static int tcm_loop_queue_status(struct se_cmd *se_cmd)
545{
546 return tcm_loop_queue_data_or_status(func: __func__,
547 se_cmd, scsi_status: se_cmd->scsi_status);
548}
549
550static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
551{
552 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
553 struct tcm_loop_cmd, tl_se_cmd);
554
555 /* Wake up tcm_loop_issue_tmr(). */
556 complete(&tl_cmd->tmr_done);
557}
558
559static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
560{
561 return;
562}
563
564static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
565{
566 switch (tl_hba->tl_proto_id) {
567 case SCSI_PROTOCOL_SAS:
568 return "SAS";
569 case SCSI_PROTOCOL_FCP:
570 return "FCP";
571 case SCSI_PROTOCOL_ISCSI:
572 return "iSCSI";
573 default:
574 break;
575 }
576
577 return "Unknown";
578}
579
580/* Start items for tcm_loop_port_cit */
581
582static int tcm_loop_port_link(
583 struct se_portal_group *se_tpg,
584 struct se_lun *lun)
585{
586 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
587 struct tcm_loop_tpg, tl_se_tpg);
588 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
589
590 atomic_inc_mb(v: &tl_tpg->tl_tpg_port_count);
591 /*
592 * Add Linux/SCSI struct scsi_device by HCTL
593 */
594 scsi_add_device(host: tl_hba->sh, channel: 0, target: tl_tpg->tl_tpgt, lun: lun->unpacked_lun);
595
596 pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
597 return 0;
598}
599
600static void tcm_loop_port_unlink(
601 struct se_portal_group *se_tpg,
602 struct se_lun *se_lun)
603{
604 struct scsi_device *sd;
605 struct tcm_loop_hba *tl_hba;
606 struct tcm_loop_tpg *tl_tpg;
607
608 tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
609 tl_hba = tl_tpg->tl_hba;
610
611 sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
612 se_lun->unpacked_lun);
613 if (!sd) {
614 pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n",
615 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
616 return;
617 }
618 /*
619 * Remove Linux/SCSI struct scsi_device by HCTL
620 */
621 scsi_remove_device(sd);
622 scsi_device_put(sd);
623
624 atomic_dec_mb(v: &tl_tpg->tl_tpg_port_count);
625
626 pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
627}
628
629/* End items for tcm_loop_port_cit */
630
631static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
632 struct config_item *item, char *page)
633{
634 struct se_portal_group *se_tpg = attrib_to_tpg(item);
635 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
636 tl_se_tpg);
637
638 return sprintf(buf: page, fmt: "%d\n", tl_tpg->tl_fabric_prot_type);
639}
640
641static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
642 struct config_item *item, const char *page, size_t count)
643{
644 struct se_portal_group *se_tpg = attrib_to_tpg(item);
645 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
646 tl_se_tpg);
647 unsigned long val;
648 int ret = kstrtoul(s: page, base: 0, res: &val);
649
650 if (ret) {
651 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
652 return ret;
653 }
654 if (val != 0 && val != 1 && val != 3) {
655 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
656 return -EINVAL;
657 }
658 tl_tpg->tl_fabric_prot_type = val;
659
660 return count;
661}
662
663CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
664
665static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
666 &tcm_loop_tpg_attrib_attr_fabric_prot_type,
667 NULL,
668};
669
670/* Start items for tcm_loop_nexus_cit */
671
672static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
673 struct se_session *se_sess, void *p)
674{
675 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
676 struct tcm_loop_tpg, tl_se_tpg);
677
678 tl_tpg->tl_nexus = p;
679 return 0;
680}
681
682static int tcm_loop_make_nexus(
683 struct tcm_loop_tpg *tl_tpg,
684 const char *name)
685{
686 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
687 struct tcm_loop_nexus *tl_nexus;
688 int ret;
689
690 if (tl_tpg->tl_nexus) {
691 pr_debug("tl_tpg->tl_nexus already exists\n");
692 return -EEXIST;
693 }
694
695 tl_nexus = kzalloc(sizeof(*tl_nexus), GFP_KERNEL);
696 if (!tl_nexus)
697 return -ENOMEM;
698
699 tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0,
700 prot_op: TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
701 name, tl_nexus, callback: tcm_loop_alloc_sess_cb);
702 if (IS_ERR(ptr: tl_nexus->se_sess)) {
703 ret = PTR_ERR(ptr: tl_nexus->se_sess);
704 kfree(objp: tl_nexus);
705 return ret;
706 }
707
708 pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n",
709 tcm_loop_dump_proto_id(tl_hba), name);
710 return 0;
711}
712
713static int tcm_loop_drop_nexus(
714 struct tcm_loop_tpg *tpg)
715{
716 struct se_session *se_sess;
717 struct tcm_loop_nexus *tl_nexus;
718
719 tl_nexus = tpg->tl_nexus;
720 if (!tl_nexus)
721 return -ENODEV;
722
723 se_sess = tl_nexus->se_sess;
724 if (!se_sess)
725 return -ENODEV;
726
727 if (atomic_read(v: &tpg->tl_tpg_port_count)) {
728 pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n",
729 atomic_read(&tpg->tl_tpg_port_count));
730 return -EPERM;
731 }
732
733 pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
734 tcm_loop_dump_proto_id(tpg->tl_hba),
735 tl_nexus->se_sess->se_node_acl->initiatorname);
736 /*
737 * Release the SCSI I_T Nexus to the emulated Target Port
738 */
739 target_remove_session(se_sess);
740 tpg->tl_nexus = NULL;
741 kfree(objp: tl_nexus);
742 return 0;
743}
744
745/* End items for tcm_loop_nexus_cit */
746
747static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
748{
749 struct se_portal_group *se_tpg = to_tpg(item);
750 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
751 struct tcm_loop_tpg, tl_se_tpg);
752 struct tcm_loop_nexus *tl_nexus;
753 ssize_t ret;
754
755 tl_nexus = tl_tpg->tl_nexus;
756 if (!tl_nexus)
757 return -ENODEV;
758
759 ret = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n",
760 tl_nexus->se_sess->se_node_acl->initiatorname);
761
762 return ret;
763}
764
765static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
766 const char *page, size_t count)
767{
768 struct se_portal_group *se_tpg = to_tpg(item);
769 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
770 struct tcm_loop_tpg, tl_se_tpg);
771 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
772 unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
773 int ret;
774 /*
775 * Shutdown the active I_T nexus if 'NULL' is passed..
776 */
777 if (!strncmp(page, "NULL", 4)) {
778 ret = tcm_loop_drop_nexus(tpg: tl_tpg);
779 return (!ret) ? count : ret;
780 }
781 /*
782 * Otherwise make sure the passed virtual Initiator port WWN matches
783 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
784 * tcm_loop_make_nexus()
785 */
786 if (strlen(page) >= TL_WWN_ADDR_LEN) {
787 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
788 page, TL_WWN_ADDR_LEN);
789 return -EINVAL;
790 }
791 snprintf(buf: &i_port[0], TL_WWN_ADDR_LEN, fmt: "%s", page);
792
793 ptr = strstr(i_port, "naa.");
794 if (ptr) {
795 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
796 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
797 i_port, tcm_loop_dump_proto_id(tl_hba));
798 return -EINVAL;
799 }
800 port_ptr = &i_port[0];
801 goto check_newline;
802 }
803 ptr = strstr(i_port, "fc.");
804 if (ptr) {
805 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
806 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
807 i_port, tcm_loop_dump_proto_id(tl_hba));
808 return -EINVAL;
809 }
810 port_ptr = &i_port[3]; /* Skip over "fc." */
811 goto check_newline;
812 }
813 ptr = strstr(i_port, "iqn.");
814 if (ptr) {
815 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
816 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
817 i_port, tcm_loop_dump_proto_id(tl_hba));
818 return -EINVAL;
819 }
820 port_ptr = &i_port[0];
821 goto check_newline;
822 }
823 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
824 i_port);
825 return -EINVAL;
826 /*
827 * Clear any trailing newline for the NAA WWN
828 */
829check_newline:
830 if (i_port[strlen(i_port)-1] == '\n')
831 i_port[strlen(i_port)-1] = '\0';
832
833 ret = tcm_loop_make_nexus(tl_tpg, name: port_ptr);
834 if (ret < 0)
835 return ret;
836
837 return count;
838}
839
840static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
841 char *page)
842{
843 struct se_portal_group *se_tpg = to_tpg(item);
844 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
845 struct tcm_loop_tpg, tl_se_tpg);
846 const char *status = NULL;
847 ssize_t ret = -EINVAL;
848
849 switch (tl_tpg->tl_transport_status) {
850 case TCM_TRANSPORT_ONLINE:
851 status = "online";
852 break;
853 case TCM_TRANSPORT_OFFLINE:
854 status = "offline";
855 break;
856 default:
857 break;
858 }
859
860 if (status)
861 ret = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", status);
862
863 return ret;
864}
865
866static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
867 const char *page, size_t count)
868{
869 struct se_portal_group *se_tpg = to_tpg(item);
870 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
871 struct tcm_loop_tpg, tl_se_tpg);
872
873 if (!strncmp(page, "online", 6)) {
874 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
875 return count;
876 }
877 if (!strncmp(page, "offline", 7)) {
878 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
879 if (tl_tpg->tl_nexus) {
880 struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
881
882 core_allocate_nexus_loss_ua(acl: tl_sess->se_node_acl);
883 }
884 return count;
885 }
886 return -EINVAL;
887}
888
889static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
890 char *page)
891{
892 struct se_portal_group *se_tpg = to_tpg(item);
893 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
894 struct tcm_loop_tpg, tl_se_tpg);
895 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
896
897 if (!tl_hba->sh)
898 return -ENODEV;
899
900 return snprintf(buf: page, PAGE_SIZE, fmt: "%d:0:%d\n",
901 tl_hba->sh->host_no, tl_tpg->tl_tpgt);
902}
903
904CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
905CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
906CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
907
908static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
909 &tcm_loop_tpg_attr_nexus,
910 &tcm_loop_tpg_attr_transport_status,
911 &tcm_loop_tpg_attr_address,
912 NULL,
913};
914
915/* Start items for tcm_loop_naa_cit */
916
917static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn,
918 const char *name)
919{
920 struct tcm_loop_hba *tl_hba = container_of(wwn,
921 struct tcm_loop_hba, tl_hba_wwn);
922 struct tcm_loop_tpg *tl_tpg;
923 int ret;
924 unsigned long tpgt;
925
926 if (strstr(name, "tpgt_") != name) {
927 pr_err("Unable to locate \"tpgt_#\" directory group\n");
928 return ERR_PTR(error: -EINVAL);
929 }
930 if (kstrtoul(s: name+5, base: 10, res: &tpgt))
931 return ERR_PTR(error: -EINVAL);
932
933 if (tpgt >= TL_TPGS_PER_HBA) {
934 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
935 tpgt, TL_TPGS_PER_HBA);
936 return ERR_PTR(error: -EINVAL);
937 }
938 tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
939 tl_tpg->tl_hba = tl_hba;
940 tl_tpg->tl_tpgt = tpgt;
941 /*
942 * Register the tl_tpg as a emulated TCM Target Endpoint
943 */
944 ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
945 if (ret < 0)
946 return ERR_PTR(error: -ENOMEM);
947
948 pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
949 tcm_loop_dump_proto_id(tl_hba),
950 config_item_name(&wwn->wwn_group.cg_item), tpgt);
951 return &tl_tpg->tl_se_tpg;
952}
953
954static void tcm_loop_drop_naa_tpg(
955 struct se_portal_group *se_tpg)
956{
957 struct se_wwn *wwn = se_tpg->se_tpg_wwn;
958 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
959 struct tcm_loop_tpg, tl_se_tpg);
960 struct tcm_loop_hba *tl_hba;
961 unsigned short tpgt;
962
963 tl_hba = tl_tpg->tl_hba;
964 tpgt = tl_tpg->tl_tpgt;
965 /*
966 * Release the I_T Nexus for the Virtual target link if present
967 */
968 tcm_loop_drop_nexus(tpg: tl_tpg);
969 /*
970 * Deregister the tl_tpg as a emulated TCM Target Endpoint
971 */
972 core_tpg_deregister(se_tpg);
973
974 tl_tpg->tl_hba = NULL;
975 tl_tpg->tl_tpgt = 0;
976
977 pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
978 tcm_loop_dump_proto_id(tl_hba),
979 config_item_name(&wwn->wwn_group.cg_item), tpgt);
980}
981
982/* End items for tcm_loop_naa_cit */
983
984/* Start items for tcm_loop_cit */
985
986static struct se_wwn *tcm_loop_make_scsi_hba(
987 struct target_fabric_configfs *tf,
988 struct config_group *group,
989 const char *name)
990{
991 struct tcm_loop_hba *tl_hba;
992 struct Scsi_Host *sh;
993 char *ptr;
994 int ret, off = 0;
995
996 tl_hba = kzalloc(sizeof(*tl_hba), GFP_KERNEL);
997 if (!tl_hba)
998 return ERR_PTR(error: -ENOMEM);
999
1000 /*
1001 * Determine the emulated Protocol Identifier and Target Port Name
1002 * based on the incoming configfs directory name.
1003 */
1004 ptr = strstr(name, "naa.");
1005 if (ptr) {
1006 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1007 goto check_len;
1008 }
1009 ptr = strstr(name, "fc.");
1010 if (ptr) {
1011 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1012 off = 3; /* Skip over "fc." */
1013 goto check_len;
1014 }
1015 ptr = strstr(name, "iqn.");
1016 if (!ptr) {
1017 pr_err("Unable to locate prefix for emulated Target Port: %s\n",
1018 name);
1019 ret = -EINVAL;
1020 goto out;
1021 }
1022 tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1023
1024check_len:
1025 if (strlen(name) >= TL_WWN_ADDR_LEN) {
1026 pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
1027 name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN);
1028 ret = -EINVAL;
1029 goto out;
1030 }
1031 snprintf(buf: &tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, fmt: "%s", &name[off]);
1032
1033 /*
1034 * Call device_register(tl_hba->dev) to register the emulated
1035 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1036 * device_register() callbacks in tcm_loop_driver_probe()
1037 */
1038 ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_host_id: tcm_loop_hba_no_cnt);
1039 if (ret)
1040 return ERR_PTR(error: ret);
1041
1042 sh = tl_hba->sh;
1043 tcm_loop_hba_no_cnt++;
1044 pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1045 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1046 return &tl_hba->tl_hba_wwn;
1047out:
1048 kfree(objp: tl_hba);
1049 return ERR_PTR(error: ret);
1050}
1051
1052static void tcm_loop_drop_scsi_hba(
1053 struct se_wwn *wwn)
1054{
1055 struct tcm_loop_hba *tl_hba = container_of(wwn,
1056 struct tcm_loop_hba, tl_hba_wwn);
1057
1058 pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1059 tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1060 tl_hba->sh->host_no);
1061 /*
1062 * Call device_unregister() on the original tl_hba->dev.
1063 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1064 * release *tl_hba;
1065 */
1066 device_unregister(dev: &tl_hba->dev);
1067}
1068
1069/* Start items for tcm_loop_cit */
1070static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1071{
1072 return sprintf(buf: page, fmt: "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1073}
1074
1075CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1076
1077static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1078 &tcm_loop_wwn_attr_version,
1079 NULL,
1080};
1081
1082/* End items for tcm_loop_cit */
1083
1084static const struct target_core_fabric_ops loop_ops = {
1085 .module = THIS_MODULE,
1086 .fabric_name = "loopback",
1087 .tpg_get_wwn = tcm_loop_get_endpoint_wwn,
1088 .tpg_get_tag = tcm_loop_get_tag,
1089 .tpg_check_demo_mode = tcm_loop_check_demo_mode,
1090 .tpg_check_prot_fabric_only = tcm_loop_check_prot_fabric_only,
1091 .check_stop_free = tcm_loop_check_stop_free,
1092 .release_cmd = tcm_loop_release_cmd,
1093 .sess_get_index = tcm_loop_sess_get_index,
1094 .write_pending = tcm_loop_write_pending,
1095 .get_cmd_state = tcm_loop_get_cmd_state,
1096 .queue_data_in = tcm_loop_queue_data_in,
1097 .queue_status = tcm_loop_queue_status,
1098 .queue_tm_rsp = tcm_loop_queue_tm_rsp,
1099 .aborted_task = tcm_loop_aborted_task,
1100 .fabric_make_wwn = tcm_loop_make_scsi_hba,
1101 .fabric_drop_wwn = tcm_loop_drop_scsi_hba,
1102 .fabric_make_tpg = tcm_loop_make_naa_tpg,
1103 .fabric_drop_tpg = tcm_loop_drop_naa_tpg,
1104 .fabric_post_link = tcm_loop_port_link,
1105 .fabric_pre_unlink = tcm_loop_port_unlink,
1106 .tfc_wwn_attrs = tcm_loop_wwn_attrs,
1107 .tfc_tpg_base_attrs = tcm_loop_tpg_attrs,
1108 .tfc_tpg_attrib_attrs = tcm_loop_tpg_attrib_attrs,
1109 .default_submit_type = TARGET_QUEUE_SUBMIT,
1110 .direct_submit_supp = 0,
1111};
1112
1113static int __init tcm_loop_fabric_init(void)
1114{
1115 int ret = -ENOMEM;
1116
1117 tcm_loop_cmd_cache = kmem_cache_create("tcm_loop_cmd_cache",
1118 sizeof(struct tcm_loop_cmd),
1119 __alignof__(struct tcm_loop_cmd),
1120 0, NULL);
1121 if (!tcm_loop_cmd_cache) {
1122 pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n");
1123 goto out;
1124 }
1125
1126 ret = tcm_loop_alloc_core_bus();
1127 if (ret)
1128 goto out_destroy_cache;
1129
1130 ret = target_register_template(fo: &loop_ops);
1131 if (ret)
1132 goto out_release_core_bus;
1133
1134 return 0;
1135
1136out_release_core_bus:
1137 tcm_loop_release_core_bus();
1138out_destroy_cache:
1139 kmem_cache_destroy(s: tcm_loop_cmd_cache);
1140out:
1141 return ret;
1142}
1143
1144static void __exit tcm_loop_fabric_exit(void)
1145{
1146 target_unregister_template(fo: &loop_ops);
1147 tcm_loop_release_core_bus();
1148 kmem_cache_destroy(s: tcm_loop_cmd_cache);
1149}
1150
1151MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1152MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1153MODULE_LICENSE("GPL");
1154module_init(tcm_loop_fabric_init);
1155module_exit(tcm_loop_fabric_exit);
1156

source code of linux/drivers/target/loopback/tcm_loop.c