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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*******************************************************************************
3 * Filename: target_core_tpg.c
4 *
5 * This file contains generic Target Portal Group related functions.
6 *
7 * (c) Copyright 2002-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <[email protected]>
10 *
11 ******************************************************************************/
12
13#include <linux/net.h>
14#include <linux/string.h>
15#include <linux/timer.h>
16#include <linux/slab.h>
17#include <linux/spinlock.h>
18#include <linux/in.h>
19#include <linux/export.h>
20#include <net/sock.h>
21#include <net/tcp.h>
22#include <scsi/scsi_proto.h>
23
24#include <target/target_core_base.h>
25#include <target/target_core_backend.h>
26#include <target/target_core_fabric.h>
27
28#include "target_core_internal.h"
29#include "target_core_alua.h"
30#include "target_core_pr.h"
31#include "target_core_ua.h"
32
33extern struct se_device *g_lun0_dev;
34static DEFINE_XARRAY_ALLOC(tpg_xa);
35
36/* __core_tpg_get_initiator_node_acl():
37 *
38 * mutex_lock(&tpg->acl_node_mutex); must be held when calling
39 */
40struct se_node_acl *__core_tpg_get_initiator_node_acl(
41 struct se_portal_group *tpg,
42 const char *initiatorname)
43{
44 struct se_node_acl *acl;
45
46 list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
47 if (!strcmp(acl->initiatorname, initiatorname))
48 return acl;
49 }
50
51 return NULL;
52}
53
54/* core_tpg_get_initiator_node_acl():
55 *
56 *
57 */
58struct se_node_acl *core_tpg_get_initiator_node_acl(
59 struct se_portal_group *tpg,
60 unsigned char *initiatorname)
61{
62 struct se_node_acl *acl;
63 /*
64 * Obtain se_node_acl->acl_kref using fabric driver provided
65 * initiatorname[] during node acl endpoint lookup driven by
66 * new se_session login.
67 *
68 * The reference is held until se_session shutdown -> release
69 * occurs via fabric driver invoked transport_deregister_session()
70 * or transport_free_session() code.
71 */
72 mutex_lock(&tpg->acl_node_mutex);
73 acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
74 if (acl) {
75 if (!kref_get_unless_zero(&acl->acl_kref))
76 acl = NULL;
77 }
78 mutex_unlock(&tpg->acl_node_mutex);
79
80 return acl;
81}
82EXPORT_SYMBOL(core_tpg_get_initiator_node_acl);
83
84void core_allocate_nexus_loss_ua(
85 struct se_node_acl *nacl)
86{
87 struct se_dev_entry *deve;
88
89 if (!nacl)
90 return;
91
92 rcu_read_lock();
93 hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
94 core_scsi3_ua_allocate(deve, 0x29,
95 ASCQ_29H_NEXUS_LOSS_OCCURRED);
96 rcu_read_unlock();
97}
98EXPORT_SYMBOL(core_allocate_nexus_loss_ua);
99
100/* core_tpg_add_node_to_devs():
101 *
102 *
103 */
104void core_tpg_add_node_to_devs(
105 struct se_node_acl *acl,
106 struct se_portal_group *tpg,
107 struct se_lun *lun_orig)
108{
109 bool lun_access_ro = true;
110 struct se_lun *lun;
111 struct se_device *dev;
112
113 mutex_lock(&tpg->tpg_lun_mutex);
114 hlist_for_each_entry_rcu(lun, &tpg->tpg_lun_hlist, link) {
115 if (lun_orig && lun != lun_orig)
116 continue;
117
118 dev = rcu_dereference_check(lun->lun_se_dev,
119 lockdep_is_held(&tpg->tpg_lun_mutex));
120 /*
121 * By default in LIO-Target $FABRIC_MOD,
122 * demo_mode_write_protect is ON, or READ_ONLY;
123 */
124 if (!tpg->se_tpg_tfo->tpg_check_demo_mode_write_protect(tpg)) {
125 lun_access_ro = false;
126 } else {
127 /*
128 * Allow only optical drives to issue R/W in default RO
129 * demo mode.
130 */
131 if (dev->transport->get_device_type(dev) == TYPE_DISK)
132 lun_access_ro = true;
133 else
134 lun_access_ro = false;
135 }
136
137 pr_debug("TARGET_CORE[%s]->TPG[%u]_LUN[%llu] - Adding %s"
138 " access for LUN in Demo Mode\n",
139 tpg->se_tpg_tfo->fabric_name,
140 tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
141 lun_access_ro ? "READ-ONLY" : "READ-WRITE");
142
143 core_enable_device_list_for_node(lun, NULL, lun->unpacked_lun,
144 lun_access_ro, acl, tpg);
145 /*
146 * Check to see if there are any existing persistent reservation
147 * APTPL pre-registrations that need to be enabled for this dynamic
148 * LUN ACL now..
149 */
150 core_scsi3_check_aptpl_registration(dev, tpg, lun, acl,
151 lun->unpacked_lun);
152 }
153 mutex_unlock(&tpg->tpg_lun_mutex);
154}
155
156static void
157target_set_nacl_queue_depth(struct se_portal_group *tpg,
158 struct se_node_acl *acl, u32 queue_depth)
159{
160 acl->queue_depth = queue_depth;
161
162 if (!acl->queue_depth) {
163 pr_warn("Queue depth for %s Initiator Node: %s is 0,"
164 "defaulting to 1.\n", tpg->se_tpg_tfo->fabric_name,
165 acl->initiatorname);
166 acl->queue_depth = 1;
167 }
168}
169
170static struct se_node_acl *target_alloc_node_acl(struct se_portal_group *tpg,
171 const unsigned char *initiatorname)
172{
173 struct se_node_acl *acl;
174 u32 queue_depth;
175
176 acl = kzalloc(max(sizeof(*acl), tpg->se_tpg_tfo->node_acl_size),
177 GFP_KERNEL);
178 if (!acl)
179 return NULL;
180
181 INIT_LIST_HEAD(&acl->acl_list);
182 INIT_LIST_HEAD(&acl->acl_sess_list);
183 INIT_HLIST_HEAD(&acl->lun_entry_hlist);
184 kref_init(&acl->acl_kref);
185 init_completion(&acl->acl_free_comp);
186 spin_lock_init(&acl->nacl_sess_lock);
187 mutex_init(&acl->lun_entry_mutex);
188 atomic_set(&acl->acl_pr_ref_count, 0);
189
190 if (tpg->se_tpg_tfo->tpg_get_default_depth)
191 queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
192 else
193 queue_depth = 1;
194 target_set_nacl_queue_depth(tpg, acl, queue_depth);
195
196 snprintf(acl->initiatorname, TRANSPORT_IQN_LEN, "%s", initiatorname);
197 acl->se_tpg = tpg;
198 acl->acl_index = scsi_get_new_index(SCSI_AUTH_INTR_INDEX);
199
200 tpg->se_tpg_tfo->set_default_node_attributes(acl);
201
202 return acl;
203}
204
205static void target_add_node_acl(struct se_node_acl *acl)
206{
207 struct se_portal_group *tpg = acl->se_tpg;
208
209 mutex_lock(&tpg->acl_node_mutex);
210 list_add_tail(&acl->acl_list, &tpg->acl_node_list);
211 mutex_unlock(&tpg->acl_node_mutex);
212
213 pr_debug("%s_TPG[%hu] - Added %s ACL with TCQ Depth: %d for %s"
214 " Initiator Node: %s\n",
215 tpg->se_tpg_tfo->fabric_name,
216 tpg->se_tpg_tfo->tpg_get_tag(tpg),
217 acl->dynamic_node_acl ? "DYNAMIC" : "",
218 acl->queue_depth,
219 tpg->se_tpg_tfo->fabric_name,
220 acl->initiatorname);
221}
222
223bool target_tpg_has_node_acl(struct se_portal_group *tpg,
224 const char *initiatorname)
225{
226 struct se_node_acl *acl;
227 bool found = false;
228
229 mutex_lock(&tpg->acl_node_mutex);
230 list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
231 if (!strcmp(acl->initiatorname, initiatorname)) {
232 found = true;
233 break;
234 }
235 }
236 mutex_unlock(&tpg->acl_node_mutex);
237
238 return found;
239}
240EXPORT_SYMBOL(target_tpg_has_node_acl);
241
242struct se_node_acl *core_tpg_check_initiator_node_acl(
243 struct se_portal_group *tpg,
244 unsigned char *initiatorname)
245{
246 struct se_node_acl *acl;
247
248 acl = core_tpg_get_initiator_node_acl(tpg, initiatorname);
249 if (acl)
250 return acl;
251
252 if (!tpg->se_tpg_tfo->tpg_check_demo_mode(tpg))
253 return NULL;
254
255 acl = target_alloc_node_acl(tpg, initiatorname);
256 if (!acl)
257 return NULL;
258 /*
259 * When allocating a dynamically generated node_acl, go ahead
260 * and take the extra kref now before returning to the fabric
261 * driver caller.
262 *
263 * Note this reference will be released at session shutdown
264 * time within transport_free_session() code.
265 */
266 kref_get(&acl->acl_kref);
267 acl->dynamic_node_acl = 1;
268
269 /*
270 * Here we only create demo-mode MappedLUNs from the active
271 * TPG LUNs if the fabric is not explicitly asking for
272 * tpg_check_demo_mode_login_only() == 1.
273 */
274 if ((tpg->se_tpg_tfo->tpg_check_demo_mode_login_only == NULL) ||
275 (tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg) != 1))
276 core_tpg_add_node_to_devs(acl, tpg, NULL);
277
278 target_add_node_acl(acl);
279 return acl;
280}
281EXPORT_SYMBOL(core_tpg_check_initiator_node_acl);
282
283void core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *nacl)
284{
285 while (atomic_read(&nacl->acl_pr_ref_count) != 0)
286 cpu_relax();
287}
288
289struct se_node_acl *core_tpg_add_initiator_node_acl(
290 struct se_portal_group *tpg,
291 const char *initiatorname)
292{
293 struct se_node_acl *acl;
294
295 mutex_lock(&tpg->acl_node_mutex);
296 acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
297 if (acl) {
298 if (acl->dynamic_node_acl) {
299 acl->dynamic_node_acl = 0;
300 pr_debug("%s_TPG[%u] - Replacing dynamic ACL"
301 " for %s\n", tpg->se_tpg_tfo->fabric_name,
302 tpg->se_tpg_tfo->tpg_get_tag(tpg), initiatorname);
303 mutex_unlock(&tpg->acl_node_mutex);
304 return acl;
305 }
306
307 pr_err("ACL entry for %s Initiator"
308 " Node %s already exists for TPG %u, ignoring"
309 " request.\n", tpg->se_tpg_tfo->fabric_name,
310 initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
311 mutex_unlock(&tpg->acl_node_mutex);
312 return ERR_PTR(-EEXIST);
313 }
314 mutex_unlock(&tpg->acl_node_mutex);
315
316 acl = target_alloc_node_acl(tpg, initiatorname);
317 if (!acl)
318 return ERR_PTR(-ENOMEM);
319
320 target_add_node_acl(acl);
321 return acl;
322}
323
324static void target_shutdown_sessions(struct se_node_acl *acl)
325{
326 struct se_session *sess;
327 unsigned long flags;
328
329restart:
330 spin_lock_irqsave(&acl->nacl_sess_lock, flags);
331 list_for_each_entry(sess, &acl->acl_sess_list, sess_acl_list) {
332 if (sess->cmd_cnt && atomic_read(&sess->cmd_cnt->stopped))
333 continue;
334
335 list_del_init(&sess->sess_acl_list);
336 spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
337
338 if (acl->se_tpg->se_tpg_tfo->close_session)
339 acl->se_tpg->se_tpg_tfo->close_session(sess);
340 goto restart;
341 }
342 spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
343}
344
345void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
346{
347 struct se_portal_group *tpg = acl->se_tpg;
348
349 mutex_lock(&tpg->acl_node_mutex);
350 if (acl->dynamic_node_acl)
351 acl->dynamic_node_acl = 0;
352 list_del_init(&acl->acl_list);
353 mutex_unlock(&tpg->acl_node_mutex);
354
355 target_shutdown_sessions(acl);
356
357 target_put_nacl(acl);
358 /*
359 * Wait for last target_put_nacl() to complete in target_complete_nacl()
360 * for active fabric session transport_deregister_session() callbacks.
361 */
362 wait_for_completion(&acl->acl_free_comp);
363
364 core_tpg_wait_for_nacl_pr_ref(acl);
365 core_free_device_list_for_node(acl, tpg);
366
367 pr_debug("%s_TPG[%hu] - Deleted ACL with TCQ Depth: %d for %s"
368 " Initiator Node: %s\n", tpg->se_tpg_tfo->fabric_name,
369 tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
370 tpg->se_tpg_tfo->fabric_name, acl->initiatorname);
371
372 kfree(acl);
373}
374
375/* core_tpg_set_initiator_node_queue_depth():
376 *
377 *
378 */
379int core_tpg_set_initiator_node_queue_depth(
380 struct se_node_acl *acl,
381 u32 queue_depth)
382{
383 struct se_portal_group *tpg = acl->se_tpg;
384
385 /*
386 * Allow the setting of se_node_acl queue_depth to be idempotent,
387 * and not force a session shutdown event if the value is not
388 * changing.
389 */
390 if (acl->queue_depth == queue_depth)
391 return 0;
392 /*
393 * User has requested to change the queue depth for a Initiator Node.
394 * Change the value in the Node's struct se_node_acl, and call
395 * target_set_nacl_queue_depth() to set the new queue depth.
396 */
397 target_set_nacl_queue_depth(tpg, acl, queue_depth);
398
399 /*
400 * Shutdown all pending sessions to force session reinstatement.
401 */
402 target_shutdown_sessions(acl);
403
404 pr_debug("Successfully changed queue depth to: %d for Initiator"
405 " Node: %s on %s Target Portal Group: %u\n", acl->queue_depth,
406 acl->initiatorname, tpg->se_tpg_tfo->fabric_name,
407 tpg->se_tpg_tfo->tpg_get_tag(tpg));
408
409 return 0;
410}
411EXPORT_SYMBOL(core_tpg_set_initiator_node_queue_depth);
412
413/* core_tpg_set_initiator_node_tag():
414 *
415 * Initiator nodeacl tags are not used internally, but may be used by
416 * userspace to emulate aliases or groups.
417 * Returns length of newly-set tag or -EINVAL.
418 */
419int core_tpg_set_initiator_node_tag(
420 struct se_portal_group *tpg,
421 struct se_node_acl *acl,
422 const char *new_tag)
423{
424 if (strlen(new_tag) >= MAX_ACL_TAG_SIZE)
425 return -EINVAL;
426
427 if (!strncmp("NULL", new_tag, 4)) {
428 acl->acl_tag[0] = '\0';
429 return 0;
430 }
431
432 return snprintf(acl->acl_tag, MAX_ACL_TAG_SIZE, "%s", new_tag);
433}
434EXPORT_SYMBOL(core_tpg_set_initiator_node_tag);
435
436static void core_tpg_lun_ref_release(struct percpu_ref *ref)
437{
438 struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
439
440 complete(&lun->lun_shutdown_comp);
441}
442
443static int target_tpg_register_rtpi(struct se_portal_group *se_tpg)
444{
445 u32 val;
446 int ret;
447
448 if (se_tpg->rtpi_manual) {
449 ret = xa_insert(&tpg_xa, se_tpg->tpg_rtpi, se_tpg, GFP_KERNEL);
450 if (ret) {
451 pr_info("%s_TPG[%hu] - Can not set RTPI %#x, it is already busy",
452 se_tpg->se_tpg_tfo->fabric_name,
453 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
454 se_tpg->tpg_rtpi);
455 return -EINVAL;
456 }
457 } else {
458 ret = xa_alloc(&tpg_xa, &val, se_tpg,
459 XA_LIMIT(1, USHRT_MAX), GFP_KERNEL);
460 if (!ret)
461 se_tpg->tpg_rtpi = val;
462 }
463
464 return ret;
465}
466
467static void target_tpg_deregister_rtpi(struct se_portal_group *se_tpg)
468{
469 if (se_tpg->tpg_rtpi && se_tpg->enabled)
470 xa_erase(&tpg_xa, se_tpg->tpg_rtpi);
471}
472
473int target_tpg_enable(struct se_portal_group *se_tpg)
474{
475 int ret;
476
477 ret = target_tpg_register_rtpi(se_tpg);
478 if (ret)
479 return ret;
480
481 ret = se_tpg->se_tpg_tfo->fabric_enable_tpg(se_tpg, true);
482 if (ret) {
483 target_tpg_deregister_rtpi(se_tpg);
484 return ret;
485 }
486
487 se_tpg->enabled = true;
488
489 return 0;
490}
491
492int target_tpg_disable(struct se_portal_group *se_tpg)
493{
494 int ret;
495
496 target_tpg_deregister_rtpi(se_tpg);
497
498 ret = se_tpg->se_tpg_tfo->fabric_enable_tpg(se_tpg, false);
499 if (!ret)
500 se_tpg->enabled = false;
501
502 return ret;
503}
504
505/* Does not change se_wwn->priv. */
506int core_tpg_register(
507 struct se_wwn *se_wwn,
508 struct se_portal_group *se_tpg,
509 int proto_id)
510{
511 int ret;
512
513 if (!se_tpg)
514 return -EINVAL;
515 /*
516 * For the typical case where core_tpg_register() is called by a
517 * fabric driver from target_core_fabric_ops->fabric_make_tpg()
518 * configfs context, use the original tf_ops pointer already saved
519 * by target-core in target_fabric_make_wwn().
520 *
521 * Otherwise, for special cases like iscsi-target discovery TPGs
522 * the caller is responsible for setting ->se_tpg_tfo ahead of
523 * calling core_tpg_register().
524 */
525 if (se_wwn)
526 se_tpg->se_tpg_tfo = se_wwn->wwn_tf->tf_ops;
527
528 if (!se_tpg->se_tpg_tfo) {
529 pr_err("Unable to locate se_tpg->se_tpg_tfo pointer\n");
530 return -EINVAL;
531 }
532
533 INIT_HLIST_HEAD(&se_tpg->tpg_lun_hlist);
534 se_tpg->proto_id = proto_id;
535 se_tpg->se_tpg_wwn = se_wwn;
536 atomic_set(&se_tpg->tpg_pr_ref_count, 0);
537 INIT_LIST_HEAD(&se_tpg->acl_node_list);
538 INIT_LIST_HEAD(&se_tpg->tpg_sess_list);
539 spin_lock_init(&se_tpg->session_lock);
540 mutex_init(&se_tpg->tpg_lun_mutex);
541 mutex_init(&se_tpg->acl_node_mutex);
542
543 if (se_tpg->proto_id >= 0) {
544 se_tpg->tpg_virt_lun0 = core_tpg_alloc_lun(se_tpg, 0);
545 if (IS_ERR(se_tpg->tpg_virt_lun0))
546 return PTR_ERR(se_tpg->tpg_virt_lun0);
547
548 ret = core_tpg_add_lun(se_tpg, se_tpg->tpg_virt_lun0,
549 true, g_lun0_dev);
550 if (ret < 0) {
551 target_tpg_free_lun(&se_tpg->tpg_virt_lun0->rcu_head);
552 return ret;
553 }
554 }
555
556 pr_debug("TARGET_CORE[%s]: Allocated portal_group for endpoint: %s, "
557 "Proto: %d, Portal Tag: %u\n", se_tpg->se_tpg_tfo->fabric_name,
558 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg) ?
559 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg) : NULL,
560 se_tpg->proto_id, se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
561
562 return 0;
563}
564EXPORT_SYMBOL(core_tpg_register);
565
566int core_tpg_deregister(struct se_portal_group *se_tpg)
567{
568 const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
569 struct se_node_acl *nacl, *nacl_tmp;
570 LIST_HEAD(node_list);
571
572 pr_debug("TARGET_CORE[%s]: Deallocating portal_group for endpoint: %s, "
573 "Proto: %d, Portal Tag: %u\n", tfo->fabric_name,
574 tfo->tpg_get_wwn(se_tpg) ? tfo->tpg_get_wwn(se_tpg) : NULL,
575 se_tpg->proto_id, tfo->tpg_get_tag(se_tpg));
576
577 while (atomic_read(&se_tpg->tpg_pr_ref_count) != 0)
578 cpu_relax();
579
580 mutex_lock(&se_tpg->acl_node_mutex);
581 list_splice_init(&se_tpg->acl_node_list, &node_list);
582 mutex_unlock(&se_tpg->acl_node_mutex);
583 /*
584 * Release any remaining demo-mode generated se_node_acl that have
585 * not been released because of TFO->tpg_check_demo_mode_cache() == 1
586 * in transport_deregister_session().
587 */
588 list_for_each_entry_safe(nacl, nacl_tmp, &node_list, acl_list) {
589 list_del_init(&nacl->acl_list);
590
591 core_tpg_wait_for_nacl_pr_ref(nacl);
592 core_free_device_list_for_node(nacl, se_tpg);
593 kfree(nacl);
594 }
595
596 if (se_tpg->proto_id >= 0) {
597 core_tpg_remove_lun(se_tpg, se_tpg->tpg_virt_lun0);
598 call_rcu(&se_tpg->tpg_virt_lun0->rcu_head, target_tpg_free_lun);
599 }
600
601 target_tpg_deregister_rtpi(se_tpg);
602
603 return 0;
604}
605EXPORT_SYMBOL(core_tpg_deregister);
606
607struct se_lun *core_tpg_alloc_lun(
608 struct se_portal_group *tpg,
609 u64 unpacked_lun)
610{
611 struct se_lun *lun;
612
613 lun = kzalloc_obj(*lun);
614 if (!lun) {
615 pr_err("Unable to allocate se_lun memory\n");
616 return ERR_PTR(-ENOMEM);
617 }
618
619 lun->lun_stats = alloc_percpu(struct scsi_port_stats);
620 if (!lun->lun_stats) {
621 pr_err("Unable to allocate se_lun stats memory\n");
622 goto free_lun;
623 }
624
625 lun->unpacked_lun = unpacked_lun;
626 atomic_set(&lun->lun_acl_count, 0);
627 init_completion(&lun->lun_shutdown_comp);
628 INIT_LIST_HEAD(&lun->lun_deve_list);
629 INIT_LIST_HEAD(&lun->lun_dev_link);
630 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
631 spin_lock_init(&lun->lun_deve_lock);
632 mutex_init(&lun->lun_tg_pt_md_mutex);
633 INIT_LIST_HEAD(&lun->lun_tg_pt_gp_link);
634 spin_lock_init(&lun->lun_tg_pt_gp_lock);
635 lun->lun_tpg = tpg;
636
637 return lun;
638
639free_lun:
640 kfree(lun);
641 return ERR_PTR(-ENOMEM);
642}
643
644void target_tpg_free_lun(struct rcu_head *head)
645{
646 struct se_lun *lun = container_of(head, struct se_lun, rcu_head);
647
648 free_percpu(lun->lun_stats);
649 kfree(lun);
650}
651
652int core_tpg_add_lun(
653 struct se_portal_group *tpg,
654 struct se_lun *lun,
655 bool lun_access_ro,
656 struct se_device *dev)
657{
658 int ret;
659
660 ret = percpu_ref_init(&lun->lun_ref, core_tpg_lun_ref_release, 0,
661 GFP_KERNEL);
662 if (ret < 0)
663 goto out;
664
665 if (!(dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
666 !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
667 target_attach_tg_pt_gp(lun, dev->t10_alua.default_tg_pt_gp);
668
669 mutex_lock(&tpg->tpg_lun_mutex);
670
671 spin_lock(&dev->se_port_lock);
672 lun->lun_index = dev->dev_index;
673 rcu_assign_pointer(lun->lun_se_dev, dev);
674 dev->export_count++;
675 list_add_tail(&lun->lun_dev_link, &dev->dev_sep_list);
676 spin_unlock(&dev->se_port_lock);
677
678 if (dev->dev_flags & DF_READ_ONLY)
679 lun->lun_access_ro = true;
680 else
681 lun->lun_access_ro = lun_access_ro;
682 if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
683 hlist_add_head_rcu(&lun->link, &tpg->tpg_lun_hlist);
684 mutex_unlock(&tpg->tpg_lun_mutex);
685
686 return 0;
687
688out:
689 return ret;
690}
691
692void core_tpg_remove_lun(
693 struct se_portal_group *tpg,
694 struct se_lun *lun)
695{
696 /*
697 * rcu_dereference_raw protected by se_lun->lun_group symlink
698 * reference to se_device->dev_group.
699 */
700 struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
701
702 lun->lun_shutdown = true;
703
704 core_clear_lun_from_tpg(lun, tpg);
705 /*
706 * Wait for any active I/O references to percpu se_lun->lun_ref to
707 * be released. Also, se_lun->lun_ref is now used by PR and ALUA
708 * logic when referencing a remote target port during ALL_TGT_PT=1
709 * and generating UNIT_ATTENTIONs for ALUA access state transition.
710 */
711 transport_clear_lun_ref(lun);
712
713 mutex_lock(&tpg->tpg_lun_mutex);
714 if (lun->lun_se_dev) {
715 target_detach_tg_pt_gp(lun);
716
717 spin_lock(&dev->se_port_lock);
718 list_del(&lun->lun_dev_link);
719 dev->export_count--;
720 rcu_assign_pointer(lun->lun_se_dev, NULL);
721 spin_unlock(&dev->se_port_lock);
722 }
723 if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
724 hlist_del_rcu(&lun->link);
725
726 lun->lun_shutdown = false;
727 mutex_unlock(&tpg->tpg_lun_mutex);
728
729 percpu_ref_exit(&lun->lun_ref);
730}