drivers/target/target_core_tpg.c

   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         tpg->num_node_acls++;
 228         mutex_unlock(&tpg->acl_node_mutex);
 229
 230         pr_debug("%s_TPG[%hu] - Added %s ACL with TCQ Depth: %d for %s"
 231                 " Initiator Node: %s\n",
 232                 tpg->se_tpg_tfo->get_fabric_name(),
 233                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
 234                 acl->dynamic_node_acl ? "DYNAMIC" : "",
 235                 acl->queue_depth,
 236                 tpg->se_tpg_tfo->get_fabric_name(),
 237                 acl->initiatorname);
 238 }
 239
 240 bool target_tpg_has_node_acl(struct se_portal_group *tpg,
 241                              const char *initiatorname)
 242 {
 243         struct se_node_acl *acl;
 244         bool found = false;
 245
 246         mutex_lock(&tpg->acl_node_mutex);
 247         list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
 248                 if (!strcmp(acl->initiatorname, initiatorname)) {
 249                         found = true;
 250                         break;
 251                 }
 252         }
 253         mutex_unlock(&tpg->acl_node_mutex);
 254
 255         return found;
 256 }
 257 EXPORT_SYMBOL(target_tpg_has_node_acl);
 258
 259 struct se_node_acl *core_tpg_check_initiator_node_acl(
 260         struct se_portal_group *tpg,
 261         unsigned char *initiatorname)
 262 {
 263         struct se_node_acl *acl;
 264
 265         acl = core_tpg_get_initiator_node_acl(tpg, initiatorname);
 266         if (acl)
 267                 return acl;
 268
 269         if (!tpg->se_tpg_tfo->tpg_check_demo_mode(tpg))
 270                 return NULL;
 271
 272         acl = target_alloc_node_acl(tpg, initiatorname);
 273         if (!acl)
 274                 return NULL;
 275         /*
 276          * When allocating a dynamically generated node_acl, go ahead
 277          * and take the extra kref now before returning to the fabric
 278          * driver caller.
 279          *
 280          * Note this reference will be released at session shutdown
 281          * time within transport_free_session() code.
 282          */
 283         kref_get(&acl->acl_kref);
 284         acl->dynamic_node_acl = 1;
 285
 286         /*
 287          * Here we only create demo-mode MappedLUNs from the active
 288          * TPG LUNs if the fabric is not explicitly asking for
 289          * tpg_check_demo_mode_login_only() == 1.
 290          */
 291         if ((tpg->se_tpg_tfo->tpg_check_demo_mode_login_only == NULL) ||
 292             (tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg) != 1))
 293                 core_tpg_add_node_to_devs(acl, tpg, NULL);
 294
 295         target_add_node_acl(acl);
 296         return acl;
 297 }
 298 EXPORT_SYMBOL(core_tpg_check_initiator_node_acl);
 299
 300 void core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *nacl)
 301 {
 302         while (atomic_read(&nacl->acl_pr_ref_count) != 0)
 303                 cpu_relax();
 304 }
 305
 306 struct se_node_acl *core_tpg_add_initiator_node_acl(
 307         struct se_portal_group *tpg,
 308         const char *initiatorname)
 309 {
 310         struct se_node_acl *acl;
 311
 312         mutex_lock(&tpg->acl_node_mutex);
 313         acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
 314         if (acl) {
 315                 if (acl->dynamic_node_acl) {
 316                         acl->dynamic_node_acl = 0;
 317                         pr_debug("%s_TPG[%u] - Replacing dynamic ACL"
 318                                 " for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
 319                                 tpg->se_tpg_tfo->tpg_get_tag(tpg), initiatorname);
 320                         mutex_unlock(&tpg->acl_node_mutex);
 321                         return acl;
 322                 }
 323
 324                 pr_err("ACL entry for %s Initiator"
 325                         " Node %s already exists for TPG %u, ignoring"
 326                         " request.\n",  tpg->se_tpg_tfo->get_fabric_name(),
 327                         initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
 328                 mutex_unlock(&tpg->acl_node_mutex);
 329                 return ERR_PTR(-EEXIST);
 330         }
 331         mutex_unlock(&tpg->acl_node_mutex);
 332
 333         acl = target_alloc_node_acl(tpg, initiatorname);
 334         if (!acl)
 335                 return ERR_PTR(-ENOMEM);
 336
 337         target_add_node_acl(acl);
 338         return acl;
 339 }
 340
 341 void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
 342 {
 343         struct se_portal_group *tpg = acl->se_tpg;
 344         LIST_HEAD(sess_list);
 345         struct se_session *sess, *sess_tmp;
 346         unsigned long flags;
 347         int rc;
 348
 349         mutex_lock(&tpg->acl_node_mutex);
 350         if (acl->dynamic_node_acl) {
 351                 acl->dynamic_node_acl = 0;
 352         }
 353         list_del_init(&acl->acl_list);
 354         tpg->num_node_acls--;
 355         mutex_unlock(&tpg->acl_node_mutex);
 356
 357         spin_lock_irqsave(&acl->nacl_sess_lock, flags);
 358         acl->acl_stop = 1;
 359
 360         list_for_each_entry_safe(sess, sess_tmp, &acl->acl_sess_list,
 361                                 sess_acl_list) {
 362                 if (sess->sess_tearing_down != 0)
 363                         continue;
 364
 365                 if (!target_get_session(sess))
 366                         continue;
 367                 list_move(&sess->sess_acl_list, &sess_list);
 368         }
 369         spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
 370
 371         list_for_each_entry_safe(sess, sess_tmp, &sess_list, sess_acl_list) {
 372                 list_del(&sess->sess_acl_list);
 373
 374                 rc = tpg->se_tpg_tfo->shutdown_session(sess);
 375                 target_put_session(sess);
 376                 if (!rc)
 377                         continue;
 378                 target_put_session(sess);
 379         }
 380         target_put_nacl(acl);
 381         /*
 382          * Wait for last target_put_nacl() to complete in target_complete_nacl()
 383          * for active fabric session transport_deregister_session() callbacks.
 384          */
 385         wait_for_completion(&acl->acl_free_comp);
 386
 387         core_tpg_wait_for_nacl_pr_ref(acl);
 388         core_free_device_list_for_node(acl, tpg);
 389
 390         pr_debug("%s_TPG[%hu] - Deleted ACL with TCQ Depth: %d for %s"
 391                 " Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
 392                 tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
 393                 tpg->se_tpg_tfo->get_fabric_name(), acl->initiatorname);
 394
 395         kfree(acl);
 396 }
 397
 398 /*      core_tpg_set_initiator_node_queue_depth():
 399  *
 400  *
 401  */
 402 int core_tpg_set_initiator_node_queue_depth(
 403         struct se_node_acl *acl,
 404         u32 queue_depth)
 405 {
 406         LIST_HEAD(sess_list);
 407         struct se_portal_group *tpg = acl->se_tpg;
 408         struct se_session *sess, *sess_tmp;
 409         unsigned long flags;
 410         int rc;
 411
 412         /*
 413          * User has requested to change the queue depth for a Initiator Node.
 414          * Change the value in the Node's struct se_node_acl, and call
 415          * target_set_nacl_queue_depth() to set the new queue depth.
 416          */
 417         target_set_nacl_queue_depth(tpg, acl, queue_depth);
 418
 419         spin_lock_irqsave(&acl->nacl_sess_lock, flags);
 420         list_for_each_entry_safe(sess, sess_tmp, &acl->acl_sess_list,
 421                                  sess_acl_list) {
 422                 if (sess->sess_tearing_down != 0)
 423                         continue;
 424                 if (!target_get_session(sess))
 425                         continue;
 426                 spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
 427
 428                 /*
 429                  * Finally call tpg->se_tpg_tfo->close_session() to force session
 430                  * reinstatement to occur if there is an active session for the
 431                  * $FABRIC_MOD Initiator Node in question.
 432                  */
 433                 rc = tpg->se_tpg_tfo->shutdown_session(sess);
 434                 target_put_session(sess);
 435                 if (!rc) {
 436                         spin_lock_irqsave(&acl->nacl_sess_lock, flags);
 437                         continue;
 438                 }
 439                 target_put_session(sess);
 440                 spin_lock_irqsave(&acl->nacl_sess_lock, flags);
 441         }
 442         spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
 443
 444         pr_debug("Successfully changed queue depth to: %d for Initiator"
 445                 " Node: %s on %s Target Portal Group: %u\n", acl->queue_depth,
 446                 acl->initiatorname, tpg->se_tpg_tfo->get_fabric_name(),
 447                 tpg->se_tpg_tfo->tpg_get_tag(tpg));
 448
 449         return 0;
 450 }
 451 EXPORT_SYMBOL(core_tpg_set_initiator_node_queue_depth);
 452
 453 /*      core_tpg_set_initiator_node_tag():
 454  *
 455  *      Initiator nodeacl tags are not used internally, but may be used by
 456  *      userspace to emulate aliases or groups.
 457  *      Returns length of newly-set tag or -EINVAL.
 458  */
 459 int core_tpg_set_initiator_node_tag(
 460         struct se_portal_group *tpg,
 461         struct se_node_acl *acl,
 462         const char *new_tag)
 463 {
 464         if (strlen(new_tag) >= MAX_ACL_TAG_SIZE)
 465                 return -EINVAL;
 466
 467         if (!strncmp("NULL", new_tag, 4)) {
 468                 acl->acl_tag[0] = '\0';
 469                 return 0;
 470         }
 471
 472         return snprintf(acl->acl_tag, MAX_ACL_TAG_SIZE, "%s", new_tag);
 473 }
 474 EXPORT_SYMBOL(core_tpg_set_initiator_node_tag);
 475
 476 static void core_tpg_lun_ref_release(struct percpu_ref *ref)
 477 {
 478         struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
 479
 480         complete(&lun->lun_shutdown_comp);
 481 }
 482
 483 int core_tpg_register(
 484         struct se_wwn *se_wwn,
 485         struct se_portal_group *se_tpg,
 486         int proto_id)
 487 {
 488         int ret;
 489
 490         if (!se_tpg)
 491                 return -EINVAL;
 492         /*
 493          * For the typical case where core_tpg_register() is called by a
 494          * fabric driver from target_core_fabric_ops->fabric_make_tpg()
 495          * configfs context, use the original tf_ops pointer already saved
 496          * by target-core in target_fabric_make_wwn().
 497          *
 498          * Otherwise, for special cases like iscsi-target discovery TPGs
 499          * the caller is responsible for setting ->se_tpg_tfo ahead of
 500          * calling core_tpg_register().
 501          */
 502         if (se_wwn)
 503                 se_tpg->se_tpg_tfo = se_wwn->wwn_tf->tf_ops;
 504
 505         if (!se_tpg->se_tpg_tfo) {
 506                 pr_err("Unable to locate se_tpg->se_tpg_tfo pointer\n");
 507                 return -EINVAL;
 508         }
 509
 510         INIT_HLIST_HEAD(&se_tpg->tpg_lun_hlist);
 511         se_tpg->proto_id = proto_id;
 512         se_tpg->se_tpg_wwn = se_wwn;
 513         atomic_set(&se_tpg->tpg_pr_ref_count, 0);
 514         INIT_LIST_HEAD(&se_tpg->acl_node_list);
 515         INIT_LIST_HEAD(&se_tpg->se_tpg_node);
 516         INIT_LIST_HEAD(&se_tpg->tpg_sess_list);
 517         spin_lock_init(&se_tpg->session_lock);
 518         mutex_init(&se_tpg->tpg_lun_mutex);
 519         mutex_init(&se_tpg->acl_node_mutex);
 520
 521         if (se_tpg->proto_id >= 0) {
 522                 se_tpg->tpg_virt_lun0 = core_tpg_alloc_lun(se_tpg, 0);
 523                 if (IS_ERR(se_tpg->tpg_virt_lun0))
 524                         return PTR_ERR(se_tpg->tpg_virt_lun0);
 525
 526                 ret = core_tpg_add_lun(se_tpg, se_tpg->tpg_virt_lun0,
 527                                 TRANSPORT_LUNFLAGS_READ_ONLY, g_lun0_dev);
 528                 if (ret < 0) {
 529                         kfree(se_tpg->tpg_virt_lun0);
 530                         return ret;
 531                 }
 532         }
 533
 534         spin_lock_bh(&tpg_lock);
 535         list_add_tail(&se_tpg->se_tpg_node, &tpg_list);
 536         spin_unlock_bh(&tpg_lock);
 537
 538         pr_debug("TARGET_CORE[%s]: Allocated portal_group for endpoint: %s, "
 539                  "Proto: %d, Portal Tag: %u\n", se_tpg->se_tpg_tfo->get_fabric_name(),
 540                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg) ?
 541                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg) : NULL,
 542                 se_tpg->proto_id, se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
 543
 544         return 0;
 545 }
 546 EXPORT_SYMBOL(core_tpg_register);
 547
 548 int core_tpg_deregister(struct se_portal_group *se_tpg)
 549 {
 550         const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
 551         struct se_node_acl *nacl, *nacl_tmp;
 552         LIST_HEAD(node_list);
 553
 554         pr_debug("TARGET_CORE[%s]: Deallocating portal_group for endpoint: %s, "
 555                  "Proto: %d, Portal Tag: %u\n", tfo->get_fabric_name(),
 556                 tfo->tpg_get_wwn(se_tpg) ? tfo->tpg_get_wwn(se_tpg) : NULL,
 557                 se_tpg->proto_id, tfo->tpg_get_tag(se_tpg));
 558
 559         spin_lock_bh(&tpg_lock);
 560         list_del(&se_tpg->se_tpg_node);
 561         spin_unlock_bh(&tpg_lock);
 562
 563         while (atomic_read(&se_tpg->tpg_pr_ref_count) != 0)
 564                 cpu_relax();
 565
 566         mutex_lock(&se_tpg->acl_node_mutex);
 567         list_splice_init(&se_tpg->acl_node_list, &node_list);
 568         mutex_unlock(&se_tpg->acl_node_mutex);
 569         /*
 570          * Release any remaining demo-mode generated se_node_acl that have
 571          * not been released because of TFO->tpg_check_demo_mode_cache() == 1
 572          * in transport_deregister_session().
 573          */
 574         list_for_each_entry_safe(nacl, nacl_tmp, &node_list, acl_list) {
 575                 list_del_init(&nacl->acl_list);
 576                 se_tpg->num_node_acls--;
 577
 578                 core_tpg_wait_for_nacl_pr_ref(nacl);
 579                 core_free_device_list_for_node(nacl, se_tpg);
 580                 kfree(nacl);
 581         }
 582
 583         if (se_tpg->proto_id >= 0) {
 584                 core_tpg_remove_lun(se_tpg, se_tpg->tpg_virt_lun0);
 585                 kfree_rcu(se_tpg->tpg_virt_lun0, rcu_head);
 586         }
 587
 588         return 0;
 589 }
 590 EXPORT_SYMBOL(core_tpg_deregister);
 591
 592 struct se_lun *core_tpg_alloc_lun(
 593         struct se_portal_group *tpg,
 594         u64 unpacked_lun)
 595 {
 596         struct se_lun *lun;
 597
 598         lun = kzalloc(sizeof(*lun), GFP_KERNEL);
 599         if (!lun) {
 600                 pr_err("Unable to allocate se_lun memory\n");
 601                 return ERR_PTR(-ENOMEM);
 602         }
 603         lun->unpacked_lun = unpacked_lun;
 604         lun->lun_link_magic = SE_LUN_LINK_MAGIC;
 605         atomic_set(&lun->lun_acl_count, 0);
 606         init_completion(&lun->lun_ref_comp);
 607         init_completion(&lun->lun_shutdown_comp);
 608         INIT_LIST_HEAD(&lun->lun_deve_list);
 609         INIT_LIST_HEAD(&lun->lun_dev_link);
 610         atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
 611         spin_lock_init(&lun->lun_deve_lock);
 612         mutex_init(&lun->lun_tg_pt_md_mutex);
 613         INIT_LIST_HEAD(&lun->lun_tg_pt_gp_link);
 614         spin_lock_init(&lun->lun_tg_pt_gp_lock);
 615         lun->lun_tpg = tpg;
 616
 617         return lun;
 618 }
 619
 620 int core_tpg_add_lun(
 621         struct se_portal_group *tpg,
 622         struct se_lun *lun,
 623         u32 lun_access,
 624         struct se_device *dev)
 625 {
 626         int ret;
 627
 628         ret = percpu_ref_init(&lun->lun_ref, core_tpg_lun_ref_release, 0,
 629                               GFP_KERNEL);
 630         if (ret < 0)
 631                 goto out;
 632
 633         ret = core_alloc_rtpi(lun, dev);
 634         if (ret)
 635                 goto out_kill_ref;
 636
 637         if (!(dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) &&
 638             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
 639                 target_attach_tg_pt_gp(lun, dev->t10_alua.default_tg_pt_gp);
 640
 641         mutex_lock(&tpg->tpg_lun_mutex);
 642
 643         spin_lock(&dev->se_port_lock);
 644         lun->lun_index = dev->dev_index;
 645         rcu_assign_pointer(lun->lun_se_dev, dev);
 646         dev->export_count++;
 647         list_add_tail(&lun->lun_dev_link, &dev->dev_sep_list);
 648         spin_unlock(&dev->se_port_lock);
 649
 650         if (dev->dev_flags & DF_READ_ONLY)
 651                 lun->lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
 652         else
 653                 lun->lun_access = lun_access;
 654         if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
 655                 hlist_add_head_rcu(&lun->link, &tpg->tpg_lun_hlist);
 656         mutex_unlock(&tpg->tpg_lun_mutex);
 657
 658         return 0;
 659
 660 out_kill_ref:
 661         percpu_ref_exit(&lun->lun_ref);
 662 out:
 663         return ret;
 664 }
 665
 666 void core_tpg_remove_lun(
 667         struct se_portal_group *tpg,
 668         struct se_lun *lun)
 669 {
 670         /*
 671          * rcu_dereference_raw protected by se_lun->lun_group symlink
 672          * reference to se_device->dev_group.
 673          */
 674         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
 675
 676         lun->lun_shutdown = true;
 677
 678         core_clear_lun_from_tpg(lun, tpg);
 679         /*
 680          * Wait for any active I/O references to percpu se_lun->lun_ref to
 681          * be released.  Also, se_lun->lun_ref is now used by PR and ALUA
 682          * logic when referencing a remote target port during ALL_TGT_PT=1
 683          * and generating UNIT_ATTENTIONs for ALUA access state transition.
 684          */
 685         transport_clear_lun_ref(lun);
 686
 687         mutex_lock(&tpg->tpg_lun_mutex);
 688         if (lun->lun_se_dev) {
 689                 target_detach_tg_pt_gp(lun);
 690
 691                 spin_lock(&dev->se_port_lock);
 692                 list_del(&lun->lun_dev_link);
 693                 dev->export_count--;
 694                 rcu_assign_pointer(lun->lun_se_dev, NULL);
 695                 spin_unlock(&dev->se_port_lock);
 696         }
 697         if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
 698                 hlist_del_rcu(&lun->link);
 699
 700         lun->lun_shutdown = false;
 701         mutex_unlock(&tpg->tpg_lun_mutex);
 702
 703         percpu_ref_exit(&lun->lun_ref);
 704 }