1 /*******************************************************************************
2  * Filename:  target_core_tpg.c
3  *
4  * This file contains generic Target Portal Group related functions.
5  *
6  * (c) Copyright 2002-2013 Datera, Inc.
7  *
8  * Nicholas A. Bellinger <nab@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  ******************************************************************************/
25 
26 #include <linux/net.h>
27 #include <linux/string.h>
28 #include <linux/timer.h>
29 #include <linux/slab.h>
30 #include <linux/spinlock.h>
31 #include <linux/in.h>
32 #include <linux/export.h>
33 #include <net/sock.h>
34 #include <net/tcp.h>
35 #include <scsi/scsi.h>
36 #include <scsi/scsi_cmnd.h>
37 
38 #include <target/target_core_base.h>
39 #include <target/target_core_backend.h>
40 #include <target/target_core_fabric.h>
41 
42 #include "target_core_internal.h"
43 #include "target_core_pr.h"
44 
45 extern struct se_device *g_lun0_dev;
46 
47 static DEFINE_SPINLOCK(tpg_lock);
48 static LIST_HEAD(tpg_list);
49 
50 /*	core_clear_initiator_node_from_tpg():
51  *
52  *
53  */
54 static void core_clear_initiator_node_from_tpg(
55 	struct se_node_acl *nacl,
56 	struct se_portal_group *tpg)
57 {
58 	int i;
59 	struct se_dev_entry *deve;
60 	struct se_lun *lun;
61 
62 	spin_lock_irq(&nacl->device_list_lock);
63 	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
64 		deve = nacl->device_list[i];
65 
66 		if (!(deve->lun_flags & TRANSPORT_LUNFLAGS_INITIATOR_ACCESS))
67 			continue;
68 
69 		if (!deve->se_lun) {
70 			pr_err("%s device entries device pointer is"
71 				" NULL, but Initiator has access.\n",
72 				tpg->se_tpg_tfo->get_fabric_name());
73 			continue;
74 		}
75 
76 		lun = deve->se_lun;
77 		spin_unlock_irq(&nacl->device_list_lock);
78 		core_disable_device_list_for_node(lun, NULL, deve->mapped_lun,
79 			TRANSPORT_LUNFLAGS_NO_ACCESS, nacl, tpg);
80 
81 		spin_lock_irq(&nacl->device_list_lock);
82 	}
83 	spin_unlock_irq(&nacl->device_list_lock);
84 }
85 
86 /*	__core_tpg_get_initiator_node_acl():
87  *
88  *	spin_lock_bh(&tpg->acl_node_lock); must be held when calling
89  */
90 struct se_node_acl *__core_tpg_get_initiator_node_acl(
91 	struct se_portal_group *tpg,
92 	const char *initiatorname)
93 {
94 	struct se_node_acl *acl;
95 
96 	list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
97 		if (!strcmp(acl->initiatorname, initiatorname))
98 			return acl;
99 	}
100 
101 	return NULL;
102 }
103 
104 /*	core_tpg_get_initiator_node_acl():
105  *
106  *
107  */
108 struct se_node_acl *core_tpg_get_initiator_node_acl(
109 	struct se_portal_group *tpg,
110 	unsigned char *initiatorname)
111 {
112 	struct se_node_acl *acl;
113 
114 	spin_lock_irq(&tpg->acl_node_lock);
115 	acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
116 	spin_unlock_irq(&tpg->acl_node_lock);
117 
118 	return acl;
119 }
120 EXPORT_SYMBOL(core_tpg_get_initiator_node_acl);
121 
122 /*	core_tpg_add_node_to_devs():
123  *
124  *
125  */
126 void core_tpg_add_node_to_devs(
127 	struct se_node_acl *acl,
128 	struct se_portal_group *tpg)
129 {
130 	int i = 0;
131 	u32 lun_access = 0;
132 	struct se_lun *lun;
133 	struct se_device *dev;
134 
135 	spin_lock(&tpg->tpg_lun_lock);
136 	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
137 		lun = tpg->tpg_lun_list[i];
138 		if (lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE)
139 			continue;
140 
141 		spin_unlock(&tpg->tpg_lun_lock);
142 
143 		dev = lun->lun_se_dev;
144 		/*
145 		 * By default in LIO-Target $FABRIC_MOD,
146 		 * demo_mode_write_protect is ON, or READ_ONLY;
147 		 */
148 		if (!tpg->se_tpg_tfo->tpg_check_demo_mode_write_protect(tpg)) {
149 			lun_access = TRANSPORT_LUNFLAGS_READ_WRITE;
150 		} else {
151 			/*
152 			 * Allow only optical drives to issue R/W in default RO
153 			 * demo mode.
154 			 */
155 			if (dev->transport->get_device_type(dev) == TYPE_DISK)
156 				lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
157 			else
158 				lun_access = TRANSPORT_LUNFLAGS_READ_WRITE;
159 		}
160 
161 		pr_debug("TARGET_CORE[%s]->TPG[%u]_LUN[%u] - Adding %s"
162 			" access for LUN in Demo Mode\n",
163 			tpg->se_tpg_tfo->get_fabric_name(),
164 			tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
165 			(lun_access == TRANSPORT_LUNFLAGS_READ_WRITE) ?
166 			"READ-WRITE" : "READ-ONLY");
167 
168 		core_enable_device_list_for_node(lun, NULL, lun->unpacked_lun,
169 				lun_access, acl, tpg);
170 		/*
171 		 * Check to see if there are any existing persistent reservation
172 		 * APTPL pre-registrations that need to be enabled for this dynamic
173 		 * LUN ACL now..
174 		 */
175 		core_scsi3_check_aptpl_registration(dev, tpg, lun, acl,
176 						    lun->unpacked_lun);
177 		spin_lock(&tpg->tpg_lun_lock);
178 	}
179 	spin_unlock(&tpg->tpg_lun_lock);
180 }
181 
182 /*      core_set_queue_depth_for_node():
183  *
184  *
185  */
186 static int core_set_queue_depth_for_node(
187 	struct se_portal_group *tpg,
188 	struct se_node_acl *acl)
189 {
190 	if (!acl->queue_depth) {
191 		pr_err("Queue depth for %s Initiator Node: %s is 0,"
192 			"defaulting to 1.\n", tpg->se_tpg_tfo->get_fabric_name(),
193 			acl->initiatorname);
194 		acl->queue_depth = 1;
195 	}
196 
197 	return 0;
198 }
199 
200 void array_free(void *array, int n)
201 {
202 	void **a = array;
203 	int i;
204 
205 	for (i = 0; i < n; i++)
206 		kfree(a[i]);
207 	kfree(a);
208 }
209 
210 static void *array_zalloc(int n, size_t size, gfp_t flags)
211 {
212 	void **a;
213 	int i;
214 
215 	a = kzalloc(n * sizeof(void*), flags);
216 	if (!a)
217 		return NULL;
218 	for (i = 0; i < n; i++) {
219 		a[i] = kzalloc(size, flags);
220 		if (!a[i]) {
221 			array_free(a, n);
222 			return NULL;
223 		}
224 	}
225 	return a;
226 }
227 
228 /*      core_create_device_list_for_node():
229  *
230  *
231  */
232 static int core_create_device_list_for_node(struct se_node_acl *nacl)
233 {
234 	struct se_dev_entry *deve;
235 	int i;
236 
237 	nacl->device_list = array_zalloc(TRANSPORT_MAX_LUNS_PER_TPG,
238 			sizeof(struct se_dev_entry), GFP_KERNEL);
239 	if (!nacl->device_list) {
240 		pr_err("Unable to allocate memory for"
241 			" struct se_node_acl->device_list\n");
242 		return -ENOMEM;
243 	}
244 	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
245 		deve = nacl->device_list[i];
246 
247 		atomic_set(&deve->ua_count, 0);
248 		atomic_set(&deve->pr_ref_count, 0);
249 		spin_lock_init(&deve->ua_lock);
250 		INIT_LIST_HEAD(&deve->alua_port_list);
251 		INIT_LIST_HEAD(&deve->ua_list);
252 	}
253 
254 	return 0;
255 }
256 
257 /*	core_tpg_check_initiator_node_acl()
258  *
259  *
260  */
261 struct se_node_acl *core_tpg_check_initiator_node_acl(
262 	struct se_portal_group *tpg,
263 	unsigned char *initiatorname)
264 {
265 	struct se_node_acl *acl;
266 
267 	acl = core_tpg_get_initiator_node_acl(tpg, initiatorname);
268 	if (acl)
269 		return acl;
270 
271 	if (!tpg->se_tpg_tfo->tpg_check_demo_mode(tpg))
272 		return NULL;
273 
274 	acl =  tpg->se_tpg_tfo->tpg_alloc_fabric_acl(tpg);
275 	if (!acl)
276 		return NULL;
277 
278 	INIT_LIST_HEAD(&acl->acl_list);
279 	INIT_LIST_HEAD(&acl->acl_sess_list);
280 	kref_init(&acl->acl_kref);
281 	init_completion(&acl->acl_free_comp);
282 	spin_lock_init(&acl->device_list_lock);
283 	spin_lock_init(&acl->nacl_sess_lock);
284 	atomic_set(&acl->acl_pr_ref_count, 0);
285 	if (tpg->se_tpg_tfo->tpg_get_default_depth)
286 		acl->queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
287 	else
288 		acl->queue_depth = 1;
289 	snprintf(acl->initiatorname, TRANSPORT_IQN_LEN, "%s", initiatorname);
290 	acl->se_tpg = tpg;
291 	acl->acl_index = scsi_get_new_index(SCSI_AUTH_INTR_INDEX);
292 	acl->dynamic_node_acl = 1;
293 
294 	tpg->se_tpg_tfo->set_default_node_attributes(acl);
295 
296 	if (core_create_device_list_for_node(acl) < 0) {
297 		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
298 		return NULL;
299 	}
300 
301 	if (core_set_queue_depth_for_node(tpg, acl) < 0) {
302 		core_free_device_list_for_node(acl, tpg);
303 		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
304 		return NULL;
305 	}
306 	/*
307 	 * Here we only create demo-mode MappedLUNs from the active
308 	 * TPG LUNs if the fabric is not explicitly asking for
309 	 * tpg_check_demo_mode_login_only() == 1.
310 	 */
311 	if ((tpg->se_tpg_tfo->tpg_check_demo_mode_login_only == NULL) ||
312 	    (tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg) != 1))
313 		core_tpg_add_node_to_devs(acl, tpg);
314 
315 	spin_lock_irq(&tpg->acl_node_lock);
316 	list_add_tail(&acl->acl_list, &tpg->acl_node_list);
317 	tpg->num_node_acls++;
318 	spin_unlock_irq(&tpg->acl_node_lock);
319 
320 	pr_debug("%s_TPG[%u] - Added DYNAMIC ACL with TCQ Depth: %d for %s"
321 		" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
322 		tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
323 		tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
324 
325 	return acl;
326 }
327 EXPORT_SYMBOL(core_tpg_check_initiator_node_acl);
328 
329 void core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *nacl)
330 {
331 	while (atomic_read(&nacl->acl_pr_ref_count) != 0)
332 		cpu_relax();
333 }
334 
335 void core_tpg_clear_object_luns(struct se_portal_group *tpg)
336 {
337 	int i;
338 	struct se_lun *lun;
339 
340 	spin_lock(&tpg->tpg_lun_lock);
341 	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
342 		lun = tpg->tpg_lun_list[i];
343 
344 		if ((lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE) ||
345 		    (lun->lun_se_dev == NULL))
346 			continue;
347 
348 		spin_unlock(&tpg->tpg_lun_lock);
349 		core_dev_del_lun(tpg, lun);
350 		spin_lock(&tpg->tpg_lun_lock);
351 	}
352 	spin_unlock(&tpg->tpg_lun_lock);
353 }
354 EXPORT_SYMBOL(core_tpg_clear_object_luns);
355 
356 struct se_node_acl *core_tpg_add_initiator_node_acl(
357 	struct se_portal_group *tpg,
358 	const char *initiatorname)
359 {
360 	struct se_node_acl *acl;
361 
362 	spin_lock_irq(&tpg->acl_node_lock);
363 	acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
364 	if (acl) {
365 		if (acl->dynamic_node_acl) {
366 			acl->dynamic_node_acl = 0;
367 			pr_debug("%s_TPG[%u] - Replacing dynamic ACL"
368 				" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
369 				tpg->se_tpg_tfo->tpg_get_tag(tpg), initiatorname);
370 			spin_unlock_irq(&tpg->acl_node_lock);
371 			goto done;
372 		}
373 
374 		pr_err("ACL entry for %s Initiator"
375 			" Node %s already exists for TPG %u, ignoring"
376 			" request.\n",  tpg->se_tpg_tfo->get_fabric_name(),
377 			initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
378 		spin_unlock_irq(&tpg->acl_node_lock);
379 		return ERR_PTR(-EEXIST);
380 	}
381 	spin_unlock_irq(&tpg->acl_node_lock);
382 
383 	acl = tpg->se_tpg_tfo->tpg_alloc_fabric_acl(tpg);
384 	if (!acl) {
385 		pr_err("struct se_node_acl pointer is NULL\n");
386 		return ERR_PTR(-EINVAL);
387 	}
388 
389 	INIT_LIST_HEAD(&acl->acl_list);
390 	INIT_LIST_HEAD(&acl->acl_sess_list);
391 	kref_init(&acl->acl_kref);
392 	init_completion(&acl->acl_free_comp);
393 	spin_lock_init(&acl->device_list_lock);
394 	spin_lock_init(&acl->nacl_sess_lock);
395 	atomic_set(&acl->acl_pr_ref_count, 0);
396 	if (tpg->se_tpg_tfo->tpg_get_default_depth)
397 		acl->queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
398 	else
399 		acl->queue_depth = 1;
400 	snprintf(acl->initiatorname, TRANSPORT_IQN_LEN, "%s", initiatorname);
401 	acl->se_tpg = tpg;
402 	acl->acl_index = scsi_get_new_index(SCSI_AUTH_INTR_INDEX);
403 
404 	tpg->se_tpg_tfo->set_default_node_attributes(acl);
405 
406 	if (core_create_device_list_for_node(acl) < 0) {
407 		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
408 		return ERR_PTR(-ENOMEM);
409 	}
410 
411 	if (core_set_queue_depth_for_node(tpg, acl) < 0) {
412 		core_free_device_list_for_node(acl, tpg);
413 		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
414 		return ERR_PTR(-EINVAL);
415 	}
416 
417 	spin_lock_irq(&tpg->acl_node_lock);
418 	list_add_tail(&acl->acl_list, &tpg->acl_node_list);
419 	tpg->num_node_acls++;
420 	spin_unlock_irq(&tpg->acl_node_lock);
421 
422 done:
423 	pr_debug("%s_TPG[%hu] - Added ACL with TCQ Depth: %d for %s"
424 		" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
425 		tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
426 		tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
427 
428 	return acl;
429 }
430 
431 void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
432 {
433 	struct se_portal_group *tpg = acl->se_tpg;
434 	LIST_HEAD(sess_list);
435 	struct se_session *sess, *sess_tmp;
436 	unsigned long flags;
437 	int rc;
438 
439 	spin_lock_irq(&tpg->acl_node_lock);
440 	if (acl->dynamic_node_acl) {
441 		acl->dynamic_node_acl = 0;
442 	}
443 	list_del(&acl->acl_list);
444 	tpg->num_node_acls--;
445 	spin_unlock_irq(&tpg->acl_node_lock);
446 
447 	spin_lock_irqsave(&acl->nacl_sess_lock, flags);
448 	acl->acl_stop = 1;
449 
450 	list_for_each_entry_safe(sess, sess_tmp, &acl->acl_sess_list,
451 				sess_acl_list) {
452 		if (sess->sess_tearing_down != 0)
453 			continue;
454 
455 		target_get_session(sess);
456 		list_move(&sess->sess_acl_list, &sess_list);
457 	}
458 	spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
459 
460 	list_for_each_entry_safe(sess, sess_tmp, &sess_list, sess_acl_list) {
461 		list_del(&sess->sess_acl_list);
462 
463 		rc = tpg->se_tpg_tfo->shutdown_session(sess);
464 		target_put_session(sess);
465 		if (!rc)
466 			continue;
467 		target_put_session(sess);
468 	}
469 	target_put_nacl(acl);
470 	/*
471 	 * Wait for last target_put_nacl() to complete in target_complete_nacl()
472 	 * for active fabric session transport_deregister_session() callbacks.
473 	 */
474 	wait_for_completion(&acl->acl_free_comp);
475 
476 	core_tpg_wait_for_nacl_pr_ref(acl);
477 	core_clear_initiator_node_from_tpg(acl, tpg);
478 	core_free_device_list_for_node(acl, tpg);
479 
480 	pr_debug("%s_TPG[%hu] - Deleted ACL with TCQ Depth: %d for %s"
481 		" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
482 		tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
483 		tpg->se_tpg_tfo->get_fabric_name(), acl->initiatorname);
484 
485 	tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
486 }
487 
488 /*	core_tpg_set_initiator_node_queue_depth():
489  *
490  *
491  */
492 int core_tpg_set_initiator_node_queue_depth(
493 	struct se_portal_group *tpg,
494 	unsigned char *initiatorname,
495 	u32 queue_depth,
496 	int force)
497 {
498 	struct se_session *sess, *init_sess = NULL;
499 	struct se_node_acl *acl;
500 	unsigned long flags;
501 	int dynamic_acl = 0;
502 
503 	spin_lock_irq(&tpg->acl_node_lock);
504 	acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
505 	if (!acl) {
506 		pr_err("Access Control List entry for %s Initiator"
507 			" Node %s does not exists for TPG %hu, ignoring"
508 			" request.\n", tpg->se_tpg_tfo->get_fabric_name(),
509 			initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
510 		spin_unlock_irq(&tpg->acl_node_lock);
511 		return -ENODEV;
512 	}
513 	if (acl->dynamic_node_acl) {
514 		acl->dynamic_node_acl = 0;
515 		dynamic_acl = 1;
516 	}
517 	spin_unlock_irq(&tpg->acl_node_lock);
518 
519 	spin_lock_irqsave(&tpg->session_lock, flags);
520 	list_for_each_entry(sess, &tpg->tpg_sess_list, sess_list) {
521 		if (sess->se_node_acl != acl)
522 			continue;
523 
524 		if (!force) {
525 			pr_err("Unable to change queue depth for %s"
526 				" Initiator Node: %s while session is"
527 				" operational.  To forcefully change the queue"
528 				" depth and force session reinstatement"
529 				" use the \"force=1\" parameter.\n",
530 				tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
531 			spin_unlock_irqrestore(&tpg->session_lock, flags);
532 
533 			spin_lock_irq(&tpg->acl_node_lock);
534 			if (dynamic_acl)
535 				acl->dynamic_node_acl = 1;
536 			spin_unlock_irq(&tpg->acl_node_lock);
537 			return -EEXIST;
538 		}
539 		/*
540 		 * Determine if the session needs to be closed by our context.
541 		 */
542 		if (!tpg->se_tpg_tfo->shutdown_session(sess))
543 			continue;
544 
545 		init_sess = sess;
546 		break;
547 	}
548 
549 	/*
550 	 * User has requested to change the queue depth for a Initiator Node.
551 	 * Change the value in the Node's struct se_node_acl, and call
552 	 * core_set_queue_depth_for_node() to add the requested queue depth.
553 	 *
554 	 * Finally call  tpg->se_tpg_tfo->close_session() to force session
555 	 * reinstatement to occur if there is an active session for the
556 	 * $FABRIC_MOD Initiator Node in question.
557 	 */
558 	acl->queue_depth = queue_depth;
559 
560 	if (core_set_queue_depth_for_node(tpg, acl) < 0) {
561 		spin_unlock_irqrestore(&tpg->session_lock, flags);
562 		/*
563 		 * Force session reinstatement if
564 		 * core_set_queue_depth_for_node() failed, because we assume
565 		 * the $FABRIC_MOD has already the set session reinstatement
566 		 * bit from tpg->se_tpg_tfo->shutdown_session() called above.
567 		 */
568 		if (init_sess)
569 			tpg->se_tpg_tfo->close_session(init_sess);
570 
571 		spin_lock_irq(&tpg->acl_node_lock);
572 		if (dynamic_acl)
573 			acl->dynamic_node_acl = 1;
574 		spin_unlock_irq(&tpg->acl_node_lock);
575 		return -EINVAL;
576 	}
577 	spin_unlock_irqrestore(&tpg->session_lock, flags);
578 	/*
579 	 * If the $FABRIC_MOD session for the Initiator Node ACL exists,
580 	 * forcefully shutdown the $FABRIC_MOD session/nexus.
581 	 */
582 	if (init_sess)
583 		tpg->se_tpg_tfo->close_session(init_sess);
584 
585 	pr_debug("Successfully changed queue depth to: %d for Initiator"
586 		" Node: %s on %s Target Portal Group: %u\n", queue_depth,
587 		initiatorname, tpg->se_tpg_tfo->get_fabric_name(),
588 		tpg->se_tpg_tfo->tpg_get_tag(tpg));
589 
590 	spin_lock_irq(&tpg->acl_node_lock);
591 	if (dynamic_acl)
592 		acl->dynamic_node_acl = 1;
593 	spin_unlock_irq(&tpg->acl_node_lock);
594 
595 	return 0;
596 }
597 EXPORT_SYMBOL(core_tpg_set_initiator_node_queue_depth);
598 
599 /*	core_tpg_set_initiator_node_tag():
600  *
601  *	Initiator nodeacl tags are not used internally, but may be used by
602  *	userspace to emulate aliases or groups.
603  *	Returns length of newly-set tag or -EINVAL.
604  */
605 int core_tpg_set_initiator_node_tag(
606 	struct se_portal_group *tpg,
607 	struct se_node_acl *acl,
608 	const char *new_tag)
609 {
610 	if (strlen(new_tag) >= MAX_ACL_TAG_SIZE)
611 		return -EINVAL;
612 
613 	if (!strncmp("NULL", new_tag, 4)) {
614 		acl->acl_tag[0] = '\0';
615 		return 0;
616 	}
617 
618 	return snprintf(acl->acl_tag, MAX_ACL_TAG_SIZE, "%s", new_tag);
619 }
620 EXPORT_SYMBOL(core_tpg_set_initiator_node_tag);
621 
622 static void core_tpg_lun_ref_release(struct percpu_ref *ref)
623 {
624 	struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
625 
626 	complete(&lun->lun_ref_comp);
627 }
628 
629 static int core_tpg_setup_virtual_lun0(struct se_portal_group *se_tpg)
630 {
631 	/* Set in core_dev_setup_virtual_lun0() */
632 	struct se_device *dev = g_lun0_dev;
633 	struct se_lun *lun = &se_tpg->tpg_virt_lun0;
634 	u32 lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
635 	int ret;
636 
637 	lun->unpacked_lun = 0;
638 	lun->lun_status = TRANSPORT_LUN_STATUS_FREE;
639 	atomic_set(&lun->lun_acl_count, 0);
640 	init_completion(&lun->lun_shutdown_comp);
641 	INIT_LIST_HEAD(&lun->lun_acl_list);
642 	spin_lock_init(&lun->lun_acl_lock);
643 	spin_lock_init(&lun->lun_sep_lock);
644 	init_completion(&lun->lun_ref_comp);
645 
646 	ret = core_tpg_add_lun(se_tpg, lun, lun_access, dev);
647 	if (ret < 0)
648 		return ret;
649 
650 	return 0;
651 }
652 
653 int core_tpg_register(
654 	const struct target_core_fabric_ops *tfo,
655 	struct se_wwn *se_wwn,
656 	struct se_portal_group *se_tpg,
657 	void *tpg_fabric_ptr,
658 	int se_tpg_type)
659 {
660 	struct se_lun *lun;
661 	u32 i;
662 
663 	se_tpg->tpg_lun_list = array_zalloc(TRANSPORT_MAX_LUNS_PER_TPG,
664 			sizeof(struct se_lun), GFP_KERNEL);
665 	if (!se_tpg->tpg_lun_list) {
666 		pr_err("Unable to allocate struct se_portal_group->"
667 				"tpg_lun_list\n");
668 		return -ENOMEM;
669 	}
670 
671 	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
672 		lun = se_tpg->tpg_lun_list[i];
673 		lun->unpacked_lun = i;
674 		lun->lun_link_magic = SE_LUN_LINK_MAGIC;
675 		lun->lun_status = TRANSPORT_LUN_STATUS_FREE;
676 		atomic_set(&lun->lun_acl_count, 0);
677 		init_completion(&lun->lun_shutdown_comp);
678 		INIT_LIST_HEAD(&lun->lun_acl_list);
679 		spin_lock_init(&lun->lun_acl_lock);
680 		spin_lock_init(&lun->lun_sep_lock);
681 		init_completion(&lun->lun_ref_comp);
682 	}
683 
684 	se_tpg->se_tpg_type = se_tpg_type;
685 	se_tpg->se_tpg_fabric_ptr = tpg_fabric_ptr;
686 	se_tpg->se_tpg_tfo = tfo;
687 	se_tpg->se_tpg_wwn = se_wwn;
688 	atomic_set(&se_tpg->tpg_pr_ref_count, 0);
689 	INIT_LIST_HEAD(&se_tpg->acl_node_list);
690 	INIT_LIST_HEAD(&se_tpg->se_tpg_node);
691 	INIT_LIST_HEAD(&se_tpg->tpg_sess_list);
692 	spin_lock_init(&se_tpg->acl_node_lock);
693 	spin_lock_init(&se_tpg->session_lock);
694 	spin_lock_init(&se_tpg->tpg_lun_lock);
695 
696 	if (se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL) {
697 		if (core_tpg_setup_virtual_lun0(se_tpg) < 0) {
698 			array_free(se_tpg->tpg_lun_list,
699 				   TRANSPORT_MAX_LUNS_PER_TPG);
700 			return -ENOMEM;
701 		}
702 	}
703 
704 	spin_lock_bh(&tpg_lock);
705 	list_add_tail(&se_tpg->se_tpg_node, &tpg_list);
706 	spin_unlock_bh(&tpg_lock);
707 
708 	pr_debug("TARGET_CORE[%s]: Allocated %s struct se_portal_group for"
709 		" endpoint: %s, Portal Tag: %u\n", tfo->get_fabric_name(),
710 		(se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL) ?
711 		"Normal" : "Discovery", (tfo->tpg_get_wwn(se_tpg) == NULL) ?
712 		"None" : tfo->tpg_get_wwn(se_tpg), tfo->tpg_get_tag(se_tpg));
713 
714 	return 0;
715 }
716 EXPORT_SYMBOL(core_tpg_register);
717 
718 int core_tpg_deregister(struct se_portal_group *se_tpg)
719 {
720 	struct se_node_acl *nacl, *nacl_tmp;
721 
722 	pr_debug("TARGET_CORE[%s]: Deallocating %s struct se_portal_group"
723 		" for endpoint: %s Portal Tag %u\n",
724 		(se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL) ?
725 		"Normal" : "Discovery", se_tpg->se_tpg_tfo->get_fabric_name(),
726 		se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
727 		se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
728 
729 	spin_lock_bh(&tpg_lock);
730 	list_del(&se_tpg->se_tpg_node);
731 	spin_unlock_bh(&tpg_lock);
732 
733 	while (atomic_read(&se_tpg->tpg_pr_ref_count) != 0)
734 		cpu_relax();
735 	/*
736 	 * Release any remaining demo-mode generated se_node_acl that have
737 	 * not been released because of TFO->tpg_check_demo_mode_cache() == 1
738 	 * in transport_deregister_session().
739 	 */
740 	spin_lock_irq(&se_tpg->acl_node_lock);
741 	list_for_each_entry_safe(nacl, nacl_tmp, &se_tpg->acl_node_list,
742 			acl_list) {
743 		list_del(&nacl->acl_list);
744 		se_tpg->num_node_acls--;
745 		spin_unlock_irq(&se_tpg->acl_node_lock);
746 
747 		core_tpg_wait_for_nacl_pr_ref(nacl);
748 		core_free_device_list_for_node(nacl, se_tpg);
749 		se_tpg->se_tpg_tfo->tpg_release_fabric_acl(se_tpg, nacl);
750 
751 		spin_lock_irq(&se_tpg->acl_node_lock);
752 	}
753 	spin_unlock_irq(&se_tpg->acl_node_lock);
754 
755 	if (se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL)
756 		core_tpg_remove_lun(se_tpg, &se_tpg->tpg_virt_lun0);
757 
758 	se_tpg->se_tpg_fabric_ptr = NULL;
759 	array_free(se_tpg->tpg_lun_list, TRANSPORT_MAX_LUNS_PER_TPG);
760 	return 0;
761 }
762 EXPORT_SYMBOL(core_tpg_deregister);
763 
764 struct se_lun *core_tpg_alloc_lun(
765 	struct se_portal_group *tpg,
766 	u32 unpacked_lun)
767 {
768 	struct se_lun *lun;
769 
770 	if (unpacked_lun > (TRANSPORT_MAX_LUNS_PER_TPG-1)) {
771 		pr_err("%s LUN: %u exceeds TRANSPORT_MAX_LUNS_PER_TPG"
772 			"-1: %u for Target Portal Group: %u\n",
773 			tpg->se_tpg_tfo->get_fabric_name(),
774 			unpacked_lun, TRANSPORT_MAX_LUNS_PER_TPG-1,
775 			tpg->se_tpg_tfo->tpg_get_tag(tpg));
776 		return ERR_PTR(-EOVERFLOW);
777 	}
778 
779 	spin_lock(&tpg->tpg_lun_lock);
780 	lun = tpg->tpg_lun_list[unpacked_lun];
781 	if (lun->lun_status == TRANSPORT_LUN_STATUS_ACTIVE) {
782 		pr_err("TPG Logical Unit Number: %u is already active"
783 			" on %s Target Portal Group: %u, ignoring request.\n",
784 			unpacked_lun, tpg->se_tpg_tfo->get_fabric_name(),
785 			tpg->se_tpg_tfo->tpg_get_tag(tpg));
786 		spin_unlock(&tpg->tpg_lun_lock);
787 		return ERR_PTR(-EINVAL);
788 	}
789 	spin_unlock(&tpg->tpg_lun_lock);
790 
791 	return lun;
792 }
793 
794 int core_tpg_add_lun(
795 	struct se_portal_group *tpg,
796 	struct se_lun *lun,
797 	u32 lun_access,
798 	struct se_device *dev)
799 {
800 	int ret;
801 
802 	ret = percpu_ref_init(&lun->lun_ref, core_tpg_lun_ref_release, 0,
803 			      GFP_KERNEL);
804 	if (ret < 0)
805 		return ret;
806 
807 	ret = core_dev_export(dev, tpg, lun);
808 	if (ret < 0) {
809 		percpu_ref_exit(&lun->lun_ref);
810 		return ret;
811 	}
812 
813 	spin_lock(&tpg->tpg_lun_lock);
814 	lun->lun_access = lun_access;
815 	lun->lun_status = TRANSPORT_LUN_STATUS_ACTIVE;
816 	spin_unlock(&tpg->tpg_lun_lock);
817 
818 	return 0;
819 }
820 
821 void core_tpg_remove_lun(
822 	struct se_portal_group *tpg,
823 	struct se_lun *lun)
824 {
825 	core_clear_lun_from_tpg(lun, tpg);
826 	transport_clear_lun_ref(lun);
827 
828 	core_dev_unexport(lun->lun_se_dev, tpg, lun);
829 
830 	spin_lock(&tpg->tpg_lun_lock);
831 	lun->lun_status = TRANSPORT_LUN_STATUS_FREE;
832 	spin_unlock(&tpg->tpg_lun_lock);
833 
834 	percpu_ref_exit(&lun->lun_ref);
835 }
836