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 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 = scsi_cmd_to_rq(scmd: sc)->tag;
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(k: 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: scsi_cmd_to_rq(scmd: sc)->tag, tmr: TMR_ABORT_TASK);
246 return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
247}
248
249/*
250 * Called from SCSI EH process context to issue a LUN_RESET TMR
251 * to struct scsi_device
252 */
253static int tcm_loop_device_reset(struct scsi_cmnd *sc)
254{
255 struct tcm_loop_hba *tl_hba;
256 struct tcm_loop_tpg *tl_tpg;
257 int ret;
258
259 /*
260 * Locate the tcm_loop_hba_t pointer
261 */
262 tl_hba = *(struct tcm_loop_hba **)shost_priv(shost: sc->device->host);
263 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
264
265 ret = tcm_loop_issue_tmr(tl_tpg, lun: sc->device->lun,
266 task: 0, tmr: TMR_LUN_RESET);
267 return (ret == TMR_FUNCTION_COMPLETE) ? SUCCESS : FAILED;
268}
269
270static int tcm_loop_target_reset(struct scsi_cmnd *sc)
271{
272 struct tcm_loop_hba *tl_hba;
273 struct tcm_loop_tpg *tl_tpg;
274
275 /*
276 * Locate the tcm_loop_hba_t pointer
277 */
278 tl_hba = *(struct tcm_loop_hba **)shost_priv(shost: sc->device->host);
279 if (!tl_hba) {
280 pr_err("Unable to perform device reset without active I_T Nexus\n");
281 return FAILED;
282 }
283 /*
284 * Locate the tl_tpg pointer from TargetID in sc->device->id
285 */
286 tl_tpg = &tl_hba->tl_hba_tpgs[sc->device->id];
287 if (tl_tpg) {
288 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
289 return SUCCESS;
290 }
291 return FAILED;
292}
293
294static const struct scsi_host_template tcm_loop_driver_template = {
295 .show_info = tcm_loop_show_info,
296 .proc_name = "tcm_loopback",
297 .name = "TCM_Loopback",
298 .queuecommand = tcm_loop_queuecommand,
299 .change_queue_depth = scsi_change_queue_depth,
300 .eh_abort_handler = tcm_loop_abort_task,
301 .eh_device_reset_handler = tcm_loop_device_reset,
302 .eh_target_reset_handler = tcm_loop_target_reset,
303 .this_id = -1,
304 .sg_tablesize = 256,
305 .max_sectors = 0xFFFF,
306 .dma_boundary = PAGE_SIZE - 1,
307 .module = THIS_MODULE,
308 .track_queue_depth = 1,
309 .cmd_size = sizeof(struct tcm_loop_cmd),
310};
311
312static int tcm_loop_driver_probe(struct device *dev)
313{
314 struct tcm_loop_hba *tl_hba;
315 struct Scsi_Host *sh;
316 int error, host_prot;
317
318 tl_hba = to_tcm_loop_hba(dev);
319
320 sh = scsi_host_alloc(&tcm_loop_driver_template,
321 sizeof(struct tcm_loop_hba));
322 if (!sh) {
323 pr_err("Unable to allocate struct scsi_host\n");
324 return -ENODEV;
325 }
326 tl_hba->sh = sh;
327
328 /*
329 * Assign the struct tcm_loop_hba pointer to struct Scsi_Host->hostdata
330 */
331 *((struct tcm_loop_hba **)sh->hostdata) = tl_hba;
332 /*
333 * Setup single ID, Channel and LUN for now..
334 */
335 sh->max_id = 2;
336 sh->max_lun = 0;
337 sh->max_channel = 0;
338 sh->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
339 sh->nr_hw_queues = tcm_loop_nr_hw_queues;
340 sh->can_queue = tcm_loop_can_queue;
341 sh->cmd_per_lun = tcm_loop_cmd_per_lun;
342
343 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
344 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
345 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
346
347 scsi_host_set_prot(shost: sh, mask: host_prot);
348 scsi_host_set_guard(shost: sh, type: SHOST_DIX_GUARD_CRC);
349
350 error = scsi_add_host(host: sh, dev: &tl_hba->dev);
351 if (error) {
352 pr_err("%s: scsi_add_host failed\n", __func__);
353 scsi_host_put(t: sh);
354 return -ENODEV;
355 }
356 return 0;
357}
358
359static void tcm_loop_driver_remove(struct device *dev)
360{
361 struct tcm_loop_hba *tl_hba;
362 struct Scsi_Host *sh;
363
364 tl_hba = to_tcm_loop_hba(dev);
365 sh = tl_hba->sh;
366
367 scsi_remove_host(sh);
368 scsi_host_put(t: sh);
369}
370
371static void tcm_loop_release_adapter(struct device *dev)
372{
373 struct tcm_loop_hba *tl_hba = to_tcm_loop_hba(dev);
374
375 kfree(objp: tl_hba);
376}
377
378/*
379 * Called from tcm_loop_make_scsi_hba() in tcm_loop_configfs.c
380 */
381static int tcm_loop_setup_hba_bus(struct tcm_loop_hba *tl_hba, int tcm_loop_host_id)
382{
383 int ret;
384
385 tl_hba->dev.bus = &tcm_loop_lld_bus;
386 tl_hba->dev.parent = tcm_loop_primary;
387 tl_hba->dev.release = &tcm_loop_release_adapter;
388 dev_set_name(dev: &tl_hba->dev, name: "tcm_loop_adapter_%d", tcm_loop_host_id);
389
390 ret = device_register(dev: &tl_hba->dev);
391 if (ret) {
392 pr_err("device_register() failed for tl_hba->dev: %d\n", ret);
393 put_device(dev: &tl_hba->dev);
394 return -ENODEV;
395 }
396
397 return 0;
398}
399
400/*
401 * Called from tcm_loop_fabric_init() in tcl_loop_fabric.c to load the emulated
402 * tcm_loop SCSI bus.
403 */
404static int tcm_loop_alloc_core_bus(void)
405{
406 int ret;
407
408 tcm_loop_primary = root_device_register("tcm_loop_0");
409 if (IS_ERR(ptr: tcm_loop_primary)) {
410 pr_err("Unable to allocate tcm_loop_primary\n");
411 return PTR_ERR(ptr: tcm_loop_primary);
412 }
413
414 ret = bus_register(bus: &tcm_loop_lld_bus);
415 if (ret) {
416 pr_err("bus_register() failed for tcm_loop_lld_bus\n");
417 goto dev_unreg;
418 }
419
420 ret = driver_register(drv: &tcm_loop_driverfs);
421 if (ret) {
422 pr_err("driver_register() failed for tcm_loop_driverfs\n");
423 goto bus_unreg;
424 }
425
426 pr_debug("Initialized TCM Loop Core Bus\n");
427 return ret;
428
429bus_unreg:
430 bus_unregister(bus: &tcm_loop_lld_bus);
431dev_unreg:
432 root_device_unregister(root: tcm_loop_primary);
433 return ret;
434}
435
436static void tcm_loop_release_core_bus(void)
437{
438 driver_unregister(drv: &tcm_loop_driverfs);
439 bus_unregister(bus: &tcm_loop_lld_bus);
440 root_device_unregister(root: tcm_loop_primary);
441
442 pr_debug("Releasing TCM Loop Core BUS\n");
443}
444
445static inline struct tcm_loop_tpg *tl_tpg(struct se_portal_group *se_tpg)
446{
447 return container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
448}
449
450static char *tcm_loop_get_endpoint_wwn(struct se_portal_group *se_tpg)
451{
452 /*
453 * Return the passed NAA identifier for the Target Port
454 */
455 return &tl_tpg(se_tpg)->tl_hba->tl_wwn_address[0];
456}
457
458static u16 tcm_loop_get_tag(struct se_portal_group *se_tpg)
459{
460 /*
461 * This Tag is used when forming SCSI Name identifier in EVPD=1 0x83
462 * to represent the SCSI Target Port.
463 */
464 return tl_tpg(se_tpg)->tl_tpgt;
465}
466
467/*
468 * Returning (1) here allows for target_core_mod struct se_node_acl to be generated
469 * based upon the incoming fabric dependent SCSI Initiator Port
470 */
471static int tcm_loop_check_demo_mode(struct se_portal_group *se_tpg)
472{
473 return 1;
474}
475
476static int tcm_loop_check_prot_fabric_only(struct se_portal_group *se_tpg)
477{
478 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
479 tl_se_tpg);
480 return tl_tpg->tl_fabric_prot_type;
481}
482
483static u32 tcm_loop_sess_get_index(struct se_session *se_sess)
484{
485 return 1;
486}
487
488static int tcm_loop_get_cmd_state(struct se_cmd *se_cmd)
489{
490 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
491 struct tcm_loop_cmd, tl_se_cmd);
492
493 return tl_cmd->sc_cmd_state;
494}
495
496static int tcm_loop_write_pending(struct se_cmd *se_cmd)
497{
498 /*
499 * Since Linux/SCSI has already sent down a struct scsi_cmnd
500 * sc->sc_data_direction of DMA_TO_DEVICE with struct scatterlist array
501 * memory, and memory has already been mapped to struct se_cmd->t_mem_list
502 * format with transport_generic_map_mem_to_cmd().
503 *
504 * We now tell TCM to add this WRITE CDB directly into the TCM storage
505 * object execution queue.
506 */
507 target_execute_cmd(cmd: se_cmd);
508 return 0;
509}
510
511static int tcm_loop_queue_data_or_status(const char *func,
512 struct se_cmd *se_cmd, u8 scsi_status)
513{
514 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
515 struct tcm_loop_cmd, tl_se_cmd);
516 struct scsi_cmnd *sc = tl_cmd->sc;
517
518 pr_debug("%s() called for scsi_cmnd: %p cdb: 0x%02x\n",
519 func, sc, sc->cmnd[0]);
520
521 if (se_cmd->sense_buffer &&
522 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
523 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
524
525 memcpy(sc->sense_buffer, se_cmd->sense_buffer,
526 SCSI_SENSE_BUFFERSIZE);
527 sc->result = SAM_STAT_CHECK_CONDITION;
528 } else
529 sc->result = scsi_status;
530
531 set_host_byte(cmd: sc, status: DID_OK);
532 if ((se_cmd->se_cmd_flags & SCF_OVERFLOW_BIT) ||
533 (se_cmd->se_cmd_flags & SCF_UNDERFLOW_BIT))
534 scsi_set_resid(cmd: sc, resid: se_cmd->residual_count);
535 return 0;
536}
537
538static int tcm_loop_queue_data_in(struct se_cmd *se_cmd)
539{
540 return tcm_loop_queue_data_or_status(func: __func__, se_cmd, scsi_status: SAM_STAT_GOOD);
541}
542
543static int tcm_loop_queue_status(struct se_cmd *se_cmd)
544{
545 return tcm_loop_queue_data_or_status(func: __func__,
546 se_cmd, scsi_status: se_cmd->scsi_status);
547}
548
549static void tcm_loop_queue_tm_rsp(struct se_cmd *se_cmd)
550{
551 struct tcm_loop_cmd *tl_cmd = container_of(se_cmd,
552 struct tcm_loop_cmd, tl_se_cmd);
553
554 /* Wake up tcm_loop_issue_tmr(). */
555 complete(&tl_cmd->tmr_done);
556}
557
558static void tcm_loop_aborted_task(struct se_cmd *se_cmd)
559{
560 return;
561}
562
563static char *tcm_loop_dump_proto_id(struct tcm_loop_hba *tl_hba)
564{
565 switch (tl_hba->tl_proto_id) {
566 case SCSI_PROTOCOL_SAS:
567 return "SAS";
568 case SCSI_PROTOCOL_FCP:
569 return "FCP";
570 case SCSI_PROTOCOL_ISCSI:
571 return "iSCSI";
572 default:
573 break;
574 }
575
576 return "Unknown";
577}
578
579/* Start items for tcm_loop_port_cit */
580
581static int tcm_loop_port_link(
582 struct se_portal_group *se_tpg,
583 struct se_lun *lun)
584{
585 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
586 struct tcm_loop_tpg, tl_se_tpg);
587 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
588
589 atomic_inc_mb(v: &tl_tpg->tl_tpg_port_count);
590 /*
591 * Add Linux/SCSI struct scsi_device by HCTL
592 */
593 scsi_add_device(host: tl_hba->sh, channel: 0, target: tl_tpg->tl_tpgt, lun: lun->unpacked_lun);
594
595 pr_debug("TCM_Loop_ConfigFS: Port Link Successful\n");
596 return 0;
597}
598
599static void tcm_loop_port_unlink(
600 struct se_portal_group *se_tpg,
601 struct se_lun *se_lun)
602{
603 struct scsi_device *sd;
604 struct tcm_loop_hba *tl_hba;
605 struct tcm_loop_tpg *tl_tpg;
606
607 tl_tpg = container_of(se_tpg, struct tcm_loop_tpg, tl_se_tpg);
608 tl_hba = tl_tpg->tl_hba;
609
610 sd = scsi_device_lookup(tl_hba->sh, 0, tl_tpg->tl_tpgt,
611 se_lun->unpacked_lun);
612 if (!sd) {
613 pr_err("Unable to locate struct scsi_device for %d:%d:%llu\n",
614 0, tl_tpg->tl_tpgt, se_lun->unpacked_lun);
615 return;
616 }
617 /*
618 * Remove Linux/SCSI struct scsi_device by HCTL
619 */
620 scsi_remove_device(sd);
621 scsi_device_put(sd);
622
623 atomic_dec_mb(v: &tl_tpg->tl_tpg_port_count);
624
625 pr_debug("TCM_Loop_ConfigFS: Port Unlink Successful\n");
626}
627
628/* End items for tcm_loop_port_cit */
629
630static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_show(
631 struct config_item *item, char *page)
632{
633 struct se_portal_group *se_tpg = attrib_to_tpg(item);
634 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
635 tl_se_tpg);
636
637 return sprintf(buf: page, fmt: "%d\n", tl_tpg->tl_fabric_prot_type);
638}
639
640static ssize_t tcm_loop_tpg_attrib_fabric_prot_type_store(
641 struct config_item *item, const char *page, size_t count)
642{
643 struct se_portal_group *se_tpg = attrib_to_tpg(item);
644 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg, struct tcm_loop_tpg,
645 tl_se_tpg);
646 unsigned long val;
647 int ret = kstrtoul(s: page, base: 0, res: &val);
648
649 if (ret) {
650 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
651 return ret;
652 }
653 if (val != 0 && val != 1 && val != 3) {
654 pr_err("Invalid qla2xxx fabric_prot_type: %lu\n", val);
655 return -EINVAL;
656 }
657 tl_tpg->tl_fabric_prot_type = val;
658
659 return count;
660}
661
662CONFIGFS_ATTR(tcm_loop_tpg_attrib_, fabric_prot_type);
663
664static struct configfs_attribute *tcm_loop_tpg_attrib_attrs[] = {
665 &tcm_loop_tpg_attrib_attr_fabric_prot_type,
666 NULL,
667};
668
669/* Start items for tcm_loop_nexus_cit */
670
671static int tcm_loop_alloc_sess_cb(struct se_portal_group *se_tpg,
672 struct se_session *se_sess, void *p)
673{
674 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
675 struct tcm_loop_tpg, tl_se_tpg);
676
677 tl_tpg->tl_nexus = p;
678 return 0;
679}
680
681static int tcm_loop_make_nexus(
682 struct tcm_loop_tpg *tl_tpg,
683 const char *name)
684{
685 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
686 struct tcm_loop_nexus *tl_nexus;
687 int ret;
688
689 if (tl_tpg->tl_nexus) {
690 pr_debug("tl_tpg->tl_nexus already exists\n");
691 return -EEXIST;
692 }
693
694 tl_nexus = kzalloc(size: sizeof(*tl_nexus), GFP_KERNEL);
695 if (!tl_nexus)
696 return -ENOMEM;
697
698 tl_nexus->se_sess = target_setup_session(&tl_tpg->tl_se_tpg, 0, 0,
699 prot_op: TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
700 name, tl_nexus, callback: tcm_loop_alloc_sess_cb);
701 if (IS_ERR(ptr: tl_nexus->se_sess)) {
702 ret = PTR_ERR(ptr: tl_nexus->se_sess);
703 kfree(objp: tl_nexus);
704 return ret;
705 }
706
707 pr_debug("TCM_Loop_ConfigFS: Established I_T Nexus to emulated %s Initiator Port: %s\n",
708 tcm_loop_dump_proto_id(tl_hba), name);
709 return 0;
710}
711
712static int tcm_loop_drop_nexus(
713 struct tcm_loop_tpg *tpg)
714{
715 struct se_session *se_sess;
716 struct tcm_loop_nexus *tl_nexus;
717
718 tl_nexus = tpg->tl_nexus;
719 if (!tl_nexus)
720 return -ENODEV;
721
722 se_sess = tl_nexus->se_sess;
723 if (!se_sess)
724 return -ENODEV;
725
726 if (atomic_read(v: &tpg->tl_tpg_port_count)) {
727 pr_err("Unable to remove TCM_Loop I_T Nexus with active TPG port count: %d\n",
728 atomic_read(&tpg->tl_tpg_port_count));
729 return -EPERM;
730 }
731
732 pr_debug("TCM_Loop_ConfigFS: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
733 tcm_loop_dump_proto_id(tpg->tl_hba),
734 tl_nexus->se_sess->se_node_acl->initiatorname);
735 /*
736 * Release the SCSI I_T Nexus to the emulated Target Port
737 */
738 target_remove_session(se_sess);
739 tpg->tl_nexus = NULL;
740 kfree(objp: tl_nexus);
741 return 0;
742}
743
744/* End items for tcm_loop_nexus_cit */
745
746static ssize_t tcm_loop_tpg_nexus_show(struct config_item *item, char *page)
747{
748 struct se_portal_group *se_tpg = to_tpg(item);
749 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
750 struct tcm_loop_tpg, tl_se_tpg);
751 struct tcm_loop_nexus *tl_nexus;
752 ssize_t ret;
753
754 tl_nexus = tl_tpg->tl_nexus;
755 if (!tl_nexus)
756 return -ENODEV;
757
758 ret = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n",
759 tl_nexus->se_sess->se_node_acl->initiatorname);
760
761 return ret;
762}
763
764static ssize_t tcm_loop_tpg_nexus_store(struct config_item *item,
765 const char *page, size_t count)
766{
767 struct se_portal_group *se_tpg = to_tpg(item);
768 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
769 struct tcm_loop_tpg, tl_se_tpg);
770 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
771 unsigned char i_port[TL_WWN_ADDR_LEN], *ptr, *port_ptr;
772 int ret;
773 /*
774 * Shutdown the active I_T nexus if 'NULL' is passed..
775 */
776 if (!strncmp(page, "NULL", 4)) {
777 ret = tcm_loop_drop_nexus(tpg: tl_tpg);
778 return (!ret) ? count : ret;
779 }
780 /*
781 * Otherwise make sure the passed virtual Initiator port WWN matches
782 * the fabric protocol_id set in tcm_loop_make_scsi_hba(), and call
783 * tcm_loop_make_nexus()
784 */
785 if (strlen(page) >= TL_WWN_ADDR_LEN) {
786 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n",
787 page, TL_WWN_ADDR_LEN);
788 return -EINVAL;
789 }
790 snprintf(buf: &i_port[0], TL_WWN_ADDR_LEN, fmt: "%s", page);
791
792 ptr = strstr(i_port, "naa.");
793 if (ptr) {
794 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_SAS) {
795 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n",
796 i_port, tcm_loop_dump_proto_id(tl_hba));
797 return -EINVAL;
798 }
799 port_ptr = &i_port[0];
800 goto check_newline;
801 }
802 ptr = strstr(i_port, "fc.");
803 if (ptr) {
804 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_FCP) {
805 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n",
806 i_port, tcm_loop_dump_proto_id(tl_hba));
807 return -EINVAL;
808 }
809 port_ptr = &i_port[3]; /* Skip over "fc." */
810 goto check_newline;
811 }
812 ptr = strstr(i_port, "iqn.");
813 if (ptr) {
814 if (tl_hba->tl_proto_id != SCSI_PROTOCOL_ISCSI) {
815 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n",
816 i_port, tcm_loop_dump_proto_id(tl_hba));
817 return -EINVAL;
818 }
819 port_ptr = &i_port[0];
820 goto check_newline;
821 }
822 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n",
823 i_port);
824 return -EINVAL;
825 /*
826 * Clear any trailing newline for the NAA WWN
827 */
828check_newline:
829 if (i_port[strlen(i_port)-1] == '\n')
830 i_port[strlen(i_port)-1] = '\0';
831
832 ret = tcm_loop_make_nexus(tl_tpg, name: port_ptr);
833 if (ret < 0)
834 return ret;
835
836 return count;
837}
838
839static ssize_t tcm_loop_tpg_transport_status_show(struct config_item *item,
840 char *page)
841{
842 struct se_portal_group *se_tpg = to_tpg(item);
843 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
844 struct tcm_loop_tpg, tl_se_tpg);
845 const char *status = NULL;
846 ssize_t ret = -EINVAL;
847
848 switch (tl_tpg->tl_transport_status) {
849 case TCM_TRANSPORT_ONLINE:
850 status = "online";
851 break;
852 case TCM_TRANSPORT_OFFLINE:
853 status = "offline";
854 break;
855 default:
856 break;
857 }
858
859 if (status)
860 ret = snprintf(buf: page, PAGE_SIZE, fmt: "%s\n", status);
861
862 return ret;
863}
864
865static ssize_t tcm_loop_tpg_transport_status_store(struct config_item *item,
866 const char *page, size_t count)
867{
868 struct se_portal_group *se_tpg = to_tpg(item);
869 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
870 struct tcm_loop_tpg, tl_se_tpg);
871
872 if (!strncmp(page, "online", 6)) {
873 tl_tpg->tl_transport_status = TCM_TRANSPORT_ONLINE;
874 return count;
875 }
876 if (!strncmp(page, "offline", 7)) {
877 tl_tpg->tl_transport_status = TCM_TRANSPORT_OFFLINE;
878 if (tl_tpg->tl_nexus) {
879 struct se_session *tl_sess = tl_tpg->tl_nexus->se_sess;
880
881 core_allocate_nexus_loss_ua(acl: tl_sess->se_node_acl);
882 }
883 return count;
884 }
885 return -EINVAL;
886}
887
888static ssize_t tcm_loop_tpg_address_show(struct config_item *item,
889 char *page)
890{
891 struct se_portal_group *se_tpg = to_tpg(item);
892 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
893 struct tcm_loop_tpg, tl_se_tpg);
894 struct tcm_loop_hba *tl_hba = tl_tpg->tl_hba;
895
896 return snprintf(buf: page, PAGE_SIZE, fmt: "%d:0:%d\n",
897 tl_hba->sh->host_no, tl_tpg->tl_tpgt);
898}
899
900CONFIGFS_ATTR(tcm_loop_tpg_, nexus);
901CONFIGFS_ATTR(tcm_loop_tpg_, transport_status);
902CONFIGFS_ATTR_RO(tcm_loop_tpg_, address);
903
904static struct configfs_attribute *tcm_loop_tpg_attrs[] = {
905 &tcm_loop_tpg_attr_nexus,
906 &tcm_loop_tpg_attr_transport_status,
907 &tcm_loop_tpg_attr_address,
908 NULL,
909};
910
911/* Start items for tcm_loop_naa_cit */
912
913static struct se_portal_group *tcm_loop_make_naa_tpg(struct se_wwn *wwn,
914 const char *name)
915{
916 struct tcm_loop_hba *tl_hba = container_of(wwn,
917 struct tcm_loop_hba, tl_hba_wwn);
918 struct tcm_loop_tpg *tl_tpg;
919 int ret;
920 unsigned long tpgt;
921
922 if (strstr(name, "tpgt_") != name) {
923 pr_err("Unable to locate \"tpgt_#\" directory group\n");
924 return ERR_PTR(error: -EINVAL);
925 }
926 if (kstrtoul(s: name+5, base: 10, res: &tpgt))
927 return ERR_PTR(error: -EINVAL);
928
929 if (tpgt >= TL_TPGS_PER_HBA) {
930 pr_err("Passed tpgt: %lu exceeds TL_TPGS_PER_HBA: %u\n",
931 tpgt, TL_TPGS_PER_HBA);
932 return ERR_PTR(error: -EINVAL);
933 }
934 tl_tpg = &tl_hba->tl_hba_tpgs[tpgt];
935 tl_tpg->tl_hba = tl_hba;
936 tl_tpg->tl_tpgt = tpgt;
937 /*
938 * Register the tl_tpg as a emulated TCM Target Endpoint
939 */
940 ret = core_tpg_register(wwn, &tl_tpg->tl_se_tpg, tl_hba->tl_proto_id);
941 if (ret < 0)
942 return ERR_PTR(error: -ENOMEM);
943
944 pr_debug("TCM_Loop_ConfigFS: Allocated Emulated %s Target Port %s,t,0x%04lx\n",
945 tcm_loop_dump_proto_id(tl_hba),
946 config_item_name(&wwn->wwn_group.cg_item), tpgt);
947 return &tl_tpg->tl_se_tpg;
948}
949
950static void tcm_loop_drop_naa_tpg(
951 struct se_portal_group *se_tpg)
952{
953 struct se_wwn *wwn = se_tpg->se_tpg_wwn;
954 struct tcm_loop_tpg *tl_tpg = container_of(se_tpg,
955 struct tcm_loop_tpg, tl_se_tpg);
956 struct tcm_loop_hba *tl_hba;
957 unsigned short tpgt;
958
959 tl_hba = tl_tpg->tl_hba;
960 tpgt = tl_tpg->tl_tpgt;
961 /*
962 * Release the I_T Nexus for the Virtual target link if present
963 */
964 tcm_loop_drop_nexus(tpg: tl_tpg);
965 /*
966 * Deregister the tl_tpg as a emulated TCM Target Endpoint
967 */
968 core_tpg_deregister(se_tpg);
969
970 tl_tpg->tl_hba = NULL;
971 tl_tpg->tl_tpgt = 0;
972
973 pr_debug("TCM_Loop_ConfigFS: Deallocated Emulated %s Target Port %s,t,0x%04x\n",
974 tcm_loop_dump_proto_id(tl_hba),
975 config_item_name(&wwn->wwn_group.cg_item), tpgt);
976}
977
978/* End items for tcm_loop_naa_cit */
979
980/* Start items for tcm_loop_cit */
981
982static struct se_wwn *tcm_loop_make_scsi_hba(
983 struct target_fabric_configfs *tf,
984 struct config_group *group,
985 const char *name)
986{
987 struct tcm_loop_hba *tl_hba;
988 struct Scsi_Host *sh;
989 char *ptr;
990 int ret, off = 0;
991
992 tl_hba = kzalloc(size: sizeof(*tl_hba), GFP_KERNEL);
993 if (!tl_hba)
994 return ERR_PTR(error: -ENOMEM);
995
996 /*
997 * Determine the emulated Protocol Identifier and Target Port Name
998 * based on the incoming configfs directory name.
999 */
1000 ptr = strstr(name, "naa.");
1001 if (ptr) {
1002 tl_hba->tl_proto_id = SCSI_PROTOCOL_SAS;
1003 goto check_len;
1004 }
1005 ptr = strstr(name, "fc.");
1006 if (ptr) {
1007 tl_hba->tl_proto_id = SCSI_PROTOCOL_FCP;
1008 off = 3; /* Skip over "fc." */
1009 goto check_len;
1010 }
1011 ptr = strstr(name, "iqn.");
1012 if (!ptr) {
1013 pr_err("Unable to locate prefix for emulated Target Port: %s\n",
1014 name);
1015 ret = -EINVAL;
1016 goto out;
1017 }
1018 tl_hba->tl_proto_id = SCSI_PROTOCOL_ISCSI;
1019
1020check_len:
1021 if (strlen(name) >= TL_WWN_ADDR_LEN) {
1022 pr_err("Emulated NAA %s Address: %s, exceeds max: %d\n",
1023 name, tcm_loop_dump_proto_id(tl_hba), TL_WWN_ADDR_LEN);
1024 ret = -EINVAL;
1025 goto out;
1026 }
1027 snprintf(buf: &tl_hba->tl_wwn_address[0], TL_WWN_ADDR_LEN, fmt: "%s", &name[off]);
1028
1029 /*
1030 * Call device_register(tl_hba->dev) to register the emulated
1031 * Linux/SCSI LLD of type struct Scsi_Host at tl_hba->sh after
1032 * device_register() callbacks in tcm_loop_driver_probe()
1033 */
1034 ret = tcm_loop_setup_hba_bus(tl_hba, tcm_loop_host_id: tcm_loop_hba_no_cnt);
1035 if (ret)
1036 return ERR_PTR(error: ret);
1037
1038 sh = tl_hba->sh;
1039 tcm_loop_hba_no_cnt++;
1040 pr_debug("TCM_Loop_ConfigFS: Allocated emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1041 tcm_loop_dump_proto_id(tl_hba), name, sh->host_no);
1042 return &tl_hba->tl_hba_wwn;
1043out:
1044 kfree(objp: tl_hba);
1045 return ERR_PTR(error: ret);
1046}
1047
1048static void tcm_loop_drop_scsi_hba(
1049 struct se_wwn *wwn)
1050{
1051 struct tcm_loop_hba *tl_hba = container_of(wwn,
1052 struct tcm_loop_hba, tl_hba_wwn);
1053
1054 pr_debug("TCM_Loop_ConfigFS: Deallocating emulated Target %s Address: %s at Linux/SCSI Host ID: %d\n",
1055 tcm_loop_dump_proto_id(tl_hba), tl_hba->tl_wwn_address,
1056 tl_hba->sh->host_no);
1057 /*
1058 * Call device_unregister() on the original tl_hba->dev.
1059 * tcm_loop_fabric_scsi.c:tcm_loop_release_adapter() will
1060 * release *tl_hba;
1061 */
1062 device_unregister(dev: &tl_hba->dev);
1063}
1064
1065/* Start items for tcm_loop_cit */
1066static ssize_t tcm_loop_wwn_version_show(struct config_item *item, char *page)
1067{
1068 return sprintf(buf: page, fmt: "TCM Loopback Fabric module %s\n", TCM_LOOP_VERSION);
1069}
1070
1071CONFIGFS_ATTR_RO(tcm_loop_wwn_, version);
1072
1073static struct configfs_attribute *tcm_loop_wwn_attrs[] = {
1074 &tcm_loop_wwn_attr_version,
1075 NULL,
1076};
1077
1078/* End items for tcm_loop_cit */
1079
1080static const struct target_core_fabric_ops loop_ops = {
1081 .module = THIS_MODULE,
1082 .fabric_name = "loopback",
1083 .tpg_get_wwn = tcm_loop_get_endpoint_wwn,
1084 .tpg_get_tag = tcm_loop_get_tag,
1085 .tpg_check_demo_mode = tcm_loop_check_demo_mode,
1086 .tpg_check_prot_fabric_only = tcm_loop_check_prot_fabric_only,
1087 .check_stop_free = tcm_loop_check_stop_free,
1088 .release_cmd = tcm_loop_release_cmd,
1089 .sess_get_index = tcm_loop_sess_get_index,
1090 .write_pending = tcm_loop_write_pending,
1091 .get_cmd_state = tcm_loop_get_cmd_state,
1092 .queue_data_in = tcm_loop_queue_data_in,
1093 .queue_status = tcm_loop_queue_status,
1094 .queue_tm_rsp = tcm_loop_queue_tm_rsp,
1095 .aborted_task = tcm_loop_aborted_task,
1096 .fabric_make_wwn = tcm_loop_make_scsi_hba,
1097 .fabric_drop_wwn = tcm_loop_drop_scsi_hba,
1098 .fabric_make_tpg = tcm_loop_make_naa_tpg,
1099 .fabric_drop_tpg = tcm_loop_drop_naa_tpg,
1100 .fabric_post_link = tcm_loop_port_link,
1101 .fabric_pre_unlink = tcm_loop_port_unlink,
1102 .tfc_wwn_attrs = tcm_loop_wwn_attrs,
1103 .tfc_tpg_base_attrs = tcm_loop_tpg_attrs,
1104 .tfc_tpg_attrib_attrs = tcm_loop_tpg_attrib_attrs,
1105 .default_submit_type = TARGET_QUEUE_SUBMIT,
1106 .direct_submit_supp = 0,
1107};
1108
1109static int __init tcm_loop_fabric_init(void)
1110{
1111 int ret = -ENOMEM;
1112
1113 tcm_loop_cmd_cache = kmem_cache_create(name: "tcm_loop_cmd_cache",
1114 size: sizeof(struct tcm_loop_cmd),
1115 align: __alignof__(struct tcm_loop_cmd),
1116 flags: 0, NULL);
1117 if (!tcm_loop_cmd_cache) {
1118 pr_debug("kmem_cache_create() for tcm_loop_cmd_cache failed\n");
1119 goto out;
1120 }
1121
1122 ret = tcm_loop_alloc_core_bus();
1123 if (ret)
1124 goto out_destroy_cache;
1125
1126 ret = target_register_template(fo: &loop_ops);
1127 if (ret)
1128 goto out_release_core_bus;
1129
1130 return 0;
1131
1132out_release_core_bus:
1133 tcm_loop_release_core_bus();
1134out_destroy_cache:
1135 kmem_cache_destroy(s: tcm_loop_cmd_cache);
1136out:
1137 return ret;
1138}
1139
1140static void __exit tcm_loop_fabric_exit(void)
1141{
1142 target_unregister_template(fo: &loop_ops);
1143 tcm_loop_release_core_bus();
1144 kmem_cache_destroy(s: tcm_loop_cmd_cache);
1145}
1146
1147MODULE_DESCRIPTION("TCM loopback virtual Linux/SCSI fabric module");
1148MODULE_AUTHOR("Nicholas A. Bellinger <nab@risingtidesystems.com>");
1149MODULE_LICENSE("GPL");
1150module_init(tcm_loop_fabric_init);
1151module_exit(tcm_loop_fabric_exit);
1152

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