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