text: /*******************************************************************************
   * Filename:  target_core_tpg.c
   *
   * This file contains generic Target Portal Group related functions.
   *
   * Copyright (c) 2002, 2003, 2004, 2005 PyX Technologies, Inc.
   * Copyright (c) 2005, 2006, 2007 SBE, Inc.
   * Copyright (c) 2007-2010 Rising Tide Systems
   * Copyright (c) 2008-2010 Linux-iSCSI.org
   *
   * Nicholas A. Bellinger <nab@kernel.org>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
   *
   ******************************************************************************/
  
  #include <linux/net.h>
  #include <linux/string.h>
  #include <linux/timer.h>
  #include <linux/slab.h>
  #include <linux/spinlock.h>
  #include <linux/in.h>
  #include <linux/export.h>
  #include <net/sock.h>
  #include <net/tcp.h>
  #include <scsi/scsi.h>
  #include <scsi/scsi_cmnd.h>
  
  #include <target/target_core_base.h>
  #include <target/target_core_backend.h>
  #include <target/target_core_fabric.h>
  
  #include "target_core_internal.h"
  
  extern struct se_device *g_lun0_dev;
  
  static DEFINE_SPINLOCK(tpg_lock);
  static LIST_HEAD(tpg_list);
  
  /*	core_clear_initiator_node_from_tpg():
   *
   *
   */
  static void core_clear_initiator_node_from_tpg(
  	struct se_node_acl *nacl,
  	struct se_portal_group *tpg)
  {
  	int i;
  	struct se_dev_entry *deve;
  	struct se_lun *lun;
  	struct se_lun_acl *acl, *acl_tmp;
  
  	spin_lock_irq(&nacl->device_list_lock);
  	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
  		deve = &nacl->device_list[i];
  
  		if (!(deve->lun_flags & TRANSPORT_LUNFLAGS_INITIATOR_ACCESS))
  			continue;
  
  		if (!deve->se_lun) {
  			pr_err("%s device entries device pointer is"
  				" NULL, but Initiator has access.\n",
  				tpg->se_tpg_tfo->get_fabric_name());
  			continue;
  		}
  
  		lun = deve->se_lun;
  		spin_unlock_irq(&nacl->device_list_lock);
  		core_update_device_list_for_node(lun, NULL, deve->mapped_lun,
  			TRANSPORT_LUNFLAGS_NO_ACCESS, nacl, tpg, 0);
  
  		spin_lock(&lun->lun_acl_lock);
  		list_for_each_entry_safe(acl, acl_tmp,
  					&lun->lun_acl_list, lacl_list) {
  			if (!strcmp(acl->initiatorname, nacl->initiatorname) &&
  			    (acl->mapped_lun == deve->mapped_lun))
  				break;
  		}
  
  		if (!acl) {
  			pr_err("Unable to locate struct se_lun_acl for %s,"
  				" mapped_lun: %u\n", nacl->initiatorname,
  				deve->mapped_lun);
  			spin_unlock(&lun->lun_acl_lock);
  			spin_lock_irq(&nacl->device_list_lock);
  			continue;
  		}
  
  		list_del(&acl->lacl_list);
  		spin_unlock(&lun->lun_acl_lock);
  
  		spin_lock_irq(&nacl->device_list_lock);
  		kfree(acl);
  	}
  	spin_unlock_irq(&nacl->device_list_lock);
  }
  
  /*	__core_tpg_get_initiator_node_acl():
   *
   *	spin_lock_bh(&tpg->acl_node_lock); must be held when calling
   */
  struct se_node_acl *__core_tpg_get_initiator_node_acl(
  	struct se_portal_group *tpg,
  	const char *initiatorname)
  {
  	struct se_node_acl *acl;
  
  	list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
  		if (!strcmp(acl->initiatorname, initiatorname))
  			return acl;
  	}
  
  	return NULL;
  }
  
  /*	core_tpg_get_initiator_node_acl():
   *
   *
   */
  struct se_node_acl *core_tpg_get_initiator_node_acl(
  	struct se_portal_group *tpg,
  	unsigned char *initiatorname)
  {
  	struct se_node_acl *acl;
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
  		if (!strcmp(acl->initiatorname, initiatorname) &&
  		    !acl->dynamic_node_acl) {
  			spin_unlock_irq(&tpg->acl_node_lock);
  			return acl;
  		}
  	}
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  	return NULL;
  }
  
  /*	core_tpg_add_node_to_devs():
   *
   *
   */
  void core_tpg_add_node_to_devs(
  	struct se_node_acl *acl,
  	struct se_portal_group *tpg)
  {
  	int i = 0;
  	u32 lun_access = 0;
  	struct se_lun *lun;
  	struct se_device *dev;
  
  	spin_lock(&tpg->tpg_lun_lock);
  	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
  		lun = &tpg->tpg_lun_list[i];
  		if (lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE)
  			continue;
  
  		spin_unlock(&tpg->tpg_lun_lock);
  
  		dev = lun->lun_se_dev;
  		/*
  		 * By default in LIO-Target $FABRIC_MOD,
  		 * demo_mode_write_protect is ON, or READ_ONLY;
  		 */
  		if (!tpg->se_tpg_tfo->tpg_check_demo_mode_write_protect(tpg)) {
  			if (dev->dev_flags & DF_READ_ONLY)
  				lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
  			else
  				lun_access = TRANSPORT_LUNFLAGS_READ_WRITE;
  		} else {
  			/*
  			 * Allow only optical drives to issue R/W in default RO
  			 * demo mode.
  			 */
  			if (dev->transport->get_device_type(dev) == TYPE_DISK)
  				lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
  			else
  				lun_access = TRANSPORT_LUNFLAGS_READ_WRITE;
  		}
  
  		pr_debug("TARGET_CORE[%s]->TPG[%u]_LUN[%u] - Adding %s"
  			" access for LUN in Demo Mode\n",
  			tpg->se_tpg_tfo->get_fabric_name(),
  			tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
  			(lun_access == TRANSPORT_LUNFLAGS_READ_WRITE) ?
  			"READ-WRITE" : "READ-ONLY");
  
  		core_update_device_list_for_node(lun, NULL, lun->unpacked_lun,
  				lun_access, acl, tpg, 1);
  		spin_lock(&tpg->tpg_lun_lock);
  	}
  	spin_unlock(&tpg->tpg_lun_lock);
  }
  
  /*      core_set_queue_depth_for_node():
   *
   *
   */
  static int core_set_queue_depth_for_node(
  	struct se_portal_group *tpg,
  	struct se_node_acl *acl)
  {
  	if (!acl->queue_depth) {
  		pr_err("Queue depth for %s Initiator Node: %s is 0,"
  			"defaulting to 1.\n", tpg->se_tpg_tfo->get_fabric_name(),
  			acl->initiatorname);
  		acl->queue_depth = 1;
  	}
  
  	return 0;
  }
  
  /*      core_create_device_list_for_node():
   *
   *
   */
  static int core_create_device_list_for_node(struct se_node_acl *nacl)
  {
  	struct se_dev_entry *deve;
  	int i;
  
  	nacl->device_list = kzalloc(sizeof(struct se_dev_entry) *
  				TRANSPORT_MAX_LUNS_PER_TPG, GFP_KERNEL);
  	if (!nacl->device_list) {
  		pr_err("Unable to allocate memory for"
  			" struct se_node_acl->device_list\n");
  		return -ENOMEM;
  	}
  	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
  		deve = &nacl->device_list[i];
  
  		atomic_set(&deve->ua_count, 0);
  		atomic_set(&deve->pr_ref_count, 0);
  		spin_lock_init(&deve->ua_lock);
  		INIT_LIST_HEAD(&deve->alua_port_list);
  		INIT_LIST_HEAD(&deve->ua_list);
  	}
  
  	return 0;
  }
  
  /*	core_tpg_check_initiator_node_acl()
   *
   *
   */
  struct se_node_acl *core_tpg_check_initiator_node_acl(
  	struct se_portal_group *tpg,
  	unsigned char *initiatorname)
  {
  	struct se_node_acl *acl;
  
  	acl = core_tpg_get_initiator_node_acl(tpg, initiatorname);
  	if (acl)
  		return acl;
  
  	if (!tpg->se_tpg_tfo->tpg_check_demo_mode(tpg))
  		return NULL;
  
  	acl =  tpg->se_tpg_tfo->tpg_alloc_fabric_acl(tpg);
  	if (!acl)
  		return NULL;
  
  	INIT_LIST_HEAD(&acl->acl_list);
  	INIT_LIST_HEAD(&acl->acl_sess_list);
  	spin_lock_init(&acl->device_list_lock);
  	spin_lock_init(&acl->nacl_sess_lock);
  	atomic_set(&acl->acl_pr_ref_count, 0);
  	acl->queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
  	snprintf(acl->initiatorname, TRANSPORT_IQN_LEN, "%s", initiatorname);
  	acl->se_tpg = tpg;
  	acl->acl_index = scsi_get_new_index(SCSI_AUTH_INTR_INDEX);
  	spin_lock_init(&acl->stats_lock);
  	acl->dynamic_node_acl = 1;
  
  	tpg->se_tpg_tfo->set_default_node_attributes(acl);
  
  	if (core_create_device_list_for_node(acl) < 0) {
  		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
  		return NULL;
  	}
  
  	if (core_set_queue_depth_for_node(tpg, acl) < 0) {
  		core_free_device_list_for_node(acl, tpg);
  		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
  		return NULL;
  	}
  	/*
  	 * Here we only create demo-mode MappedLUNs from the active
  	 * TPG LUNs if the fabric is not explictly asking for
  	 * tpg_check_demo_mode_login_only() == 1.
  	 */
  	if ((tpg->se_tpg_tfo->tpg_check_demo_mode_login_only != NULL) &&
  	    (tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg) == 1))
  		do { ; } while (0);
  	else
  		core_tpg_add_node_to_devs(acl, tpg);
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	list_add_tail(&acl->acl_list, &tpg->acl_node_list);
  	tpg->num_node_acls++;
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  	pr_debug("%s_TPG[%u] - Added DYNAMIC ACL with TCQ Depth: %d for %s"
  		" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
  		tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
  		tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
  
  	return acl;
  }
  EXPORT_SYMBOL(core_tpg_check_initiator_node_acl);
  
  void core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *nacl)
  {
  	while (atomic_read(&nacl->acl_pr_ref_count) != 0)
  		cpu_relax();
  }
  
  void core_tpg_clear_object_luns(struct se_portal_group *tpg)
  {
  	int i, ret;
  	struct se_lun *lun;
  
  	spin_lock(&tpg->tpg_lun_lock);
  	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
  		lun = &tpg->tpg_lun_list[i];
  
  		if ((lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE) ||
  		    (lun->lun_se_dev == NULL))
  			continue;
  
  		spin_unlock(&tpg->tpg_lun_lock);
  		ret = core_dev_del_lun(tpg, lun->unpacked_lun);
  		spin_lock(&tpg->tpg_lun_lock);
  	}
  	spin_unlock(&tpg->tpg_lun_lock);
  }
  EXPORT_SYMBOL(core_tpg_clear_object_luns);
  
  /*	core_tpg_add_initiator_node_acl():
   *
   *
   */
  struct se_node_acl *core_tpg_add_initiator_node_acl(
  	struct se_portal_group *tpg,
  	struct se_node_acl *se_nacl,
  	const char *initiatorname,
  	u32 queue_depth)
  {
  	struct se_node_acl *acl = NULL;
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
  	if (acl) {
  		if (acl->dynamic_node_acl) {
  			acl->dynamic_node_acl = 0;
  			pr_debug("%s_TPG[%u] - Replacing dynamic ACL"
  				" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
  				tpg->se_tpg_tfo->tpg_get_tag(tpg), initiatorname);
  			spin_unlock_irq(&tpg->acl_node_lock);
  			/*
  			 * Release the locally allocated struct se_node_acl
  			 * because * core_tpg_add_initiator_node_acl() returned
  			 * a pointer to an existing demo mode node ACL.
  			 */
  			if (se_nacl)
  				tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg,
  							se_nacl);
  			goto done;
  		}
  
  		pr_err("ACL entry for %s Initiator"
  			" Node %s already exists for TPG %u, ignoring"
  			" request.\n",  tpg->se_tpg_tfo->get_fabric_name(),
  			initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
  		spin_unlock_irq(&tpg->acl_node_lock);
  		return ERR_PTR(-EEXIST);
  	}
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  	if (!se_nacl) {
  		pr_err("struct se_node_acl pointer is NULL\n");
  		return ERR_PTR(-EINVAL);
  	}
  	/*
  	 * For v4.x logic the se_node_acl_s is hanging off a fabric
  	 * dependent structure allocated via
  	 * struct target_core_fabric_ops->fabric_make_nodeacl()
  	 */
  	acl = se_nacl;
  
  	INIT_LIST_HEAD(&acl->acl_list);
  	INIT_LIST_HEAD(&acl->acl_sess_list);
  	spin_lock_init(&acl->device_list_lock);
  	spin_lock_init(&acl->nacl_sess_lock);
  	atomic_set(&acl->acl_pr_ref_count, 0);
  	acl->queue_depth = queue_depth;
  	snprintf(acl->initiatorname, TRANSPORT_IQN_LEN, "%s", initiatorname);
  	acl->se_tpg = tpg;
  	acl->acl_index = scsi_get_new_index(SCSI_AUTH_INTR_INDEX);
  	spin_lock_init(&acl->stats_lock);
  
  	tpg->se_tpg_tfo->set_default_node_attributes(acl);
  
  	if (core_create_device_list_for_node(acl) < 0) {
  		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
  		return ERR_PTR(-ENOMEM);
  	}
  
  	if (core_set_queue_depth_for_node(tpg, acl) < 0) {
  		core_free_device_list_for_node(acl, tpg);
  		tpg->se_tpg_tfo->tpg_release_fabric_acl(tpg, acl);
  		return ERR_PTR(-EINVAL);
  	}
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	list_add_tail(&acl->acl_list, &tpg->acl_node_list);
  	tpg->num_node_acls++;
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  done:
  	pr_debug("%s_TPG[%hu] - Added ACL with TCQ Depth: %d for %s"
  		" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
  		tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
  		tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
  
  	return acl;
  }
  EXPORT_SYMBOL(core_tpg_add_initiator_node_acl);
  
  /*	core_tpg_del_initiator_node_acl():
   *
   *
   */
  int core_tpg_del_initiator_node_acl(
  	struct se_portal_group *tpg,
  	struct se_node_acl *acl,
  	int force)
  {
  	struct se_session *sess, *sess_tmp;
  	int dynamic_acl = 0;
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	if (acl->dynamic_node_acl) {
  		acl->dynamic_node_acl = 0;
  		dynamic_acl = 1;
  	}
  	list_del(&acl->acl_list);
  	tpg->num_node_acls--;
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  	spin_lock_bh(&tpg->session_lock);
  	list_for_each_entry_safe(sess, sess_tmp,
  				&tpg->tpg_sess_list, sess_list) {
  		if (sess->se_node_acl != acl)
  			continue;
  		/*
  		 * Determine if the session needs to be closed by our context.
  		 */
  		if (!tpg->se_tpg_tfo->shutdown_session(sess))
  			continue;
  
  		spin_unlock_bh(&tpg->session_lock);
  		/*
  		 * If the $FABRIC_MOD session for the Initiator Node ACL exists,
  		 * forcefully shutdown the $FABRIC_MOD session/nexus.
  		 */
  		tpg->se_tpg_tfo->close_session(sess);
  
  		spin_lock_bh(&tpg->session_lock);
  	}
  	spin_unlock_bh(&tpg->session_lock);
  
  	core_tpg_wait_for_nacl_pr_ref(acl);
  	core_clear_initiator_node_from_tpg(acl, tpg);
  	core_free_device_list_for_node(acl, tpg);
  
  	pr_debug("%s_TPG[%hu] - Deleted ACL with TCQ Depth: %d for %s"
  		" Initiator Node: %s\n", tpg->se_tpg_tfo->get_fabric_name(),
  		tpg->se_tpg_tfo->tpg_get_tag(tpg), acl->queue_depth,
  		tpg->se_tpg_tfo->get_fabric_name(), acl->initiatorname);
  
  	return 0;
  }
  EXPORT_SYMBOL(core_tpg_del_initiator_node_acl);
  
  /*	core_tpg_set_initiator_node_queue_depth():
   *
   *
   */
  int core_tpg_set_initiator_node_queue_depth(
  	struct se_portal_group *tpg,
  	unsigned char *initiatorname,
  	u32 queue_depth,
  	int force)
  {
  	struct se_session *sess, *init_sess = NULL;
  	struct se_node_acl *acl;
  	int dynamic_acl = 0;
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
  	if (!acl) {
  		pr_err("Access Control List entry for %s Initiator"
  			" Node %s does not exists for TPG %hu, ignoring"
  			" request.\n", tpg->se_tpg_tfo->get_fabric_name(),
  			initiatorname, tpg->se_tpg_tfo->tpg_get_tag(tpg));
  		spin_unlock_irq(&tpg->acl_node_lock);
  		return -ENODEV;
  	}
  	if (acl->dynamic_node_acl) {
  		acl->dynamic_node_acl = 0;
  		dynamic_acl = 1;
  	}
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  	spin_lock_bh(&tpg->session_lock);
  	list_for_each_entry(sess, &tpg->tpg_sess_list, sess_list) {
  		if (sess->se_node_acl != acl)
  			continue;
  
  		if (!force) {
  			pr_err("Unable to change queue depth for %s"
  				" Initiator Node: %s while session is"
  				" operational.  To forcefully change the queue"
  				" depth and force session reinstatement"
  				" use the \"force=1\" parameter.\n",
  				tpg->se_tpg_tfo->get_fabric_name(), initiatorname);
  			spin_unlock_bh(&tpg->session_lock);
  
  			spin_lock_irq(&tpg->acl_node_lock);
  			if (dynamic_acl)
  				acl->dynamic_node_acl = 1;
  			spin_unlock_irq(&tpg->acl_node_lock);
  			return -EEXIST;
  		}
  		/*
  		 * Determine if the session needs to be closed by our context.
  		 */
  		if (!tpg->se_tpg_tfo->shutdown_session(sess))
  			continue;
  
  		init_sess = sess;
  		break;
  	}
  
  	/*
  	 * User has requested to change the queue depth for a Initiator Node.
  	 * Change the value in the Node's struct se_node_acl, and call
  	 * core_set_queue_depth_for_node() to add the requested queue depth.
  	 *
  	 * Finally call  tpg->se_tpg_tfo->close_session() to force session
  	 * reinstatement to occur if there is an active session for the
  	 * $FABRIC_MOD Initiator Node in question.
  	 */
  	acl->queue_depth = queue_depth;
  
  	if (core_set_queue_depth_for_node(tpg, acl) < 0) {
  		spin_unlock_bh(&tpg->session_lock);
  		/*
  		 * Force session reinstatement if
  		 * core_set_queue_depth_for_node() failed, because we assume
  		 * the $FABRIC_MOD has already the set session reinstatement
  		 * bit from tpg->se_tpg_tfo->shutdown_session() called above.
  		 */
  		if (init_sess)
  			tpg->se_tpg_tfo->close_session(init_sess);
  
  		spin_lock_irq(&tpg->acl_node_lock);
  		if (dynamic_acl)
  			acl->dynamic_node_acl = 1;
  		spin_unlock_irq(&tpg->acl_node_lock);
  		return -EINVAL;
  	}
  	spin_unlock_bh(&tpg->session_lock);
  	/*
  	 * If the $FABRIC_MOD session for the Initiator Node ACL exists,
  	 * forcefully shutdown the $FABRIC_MOD session/nexus.
  	 */
  	if (init_sess)
  		tpg->se_tpg_tfo->close_session(init_sess);
  
  	pr_debug("Successfully changed queue depth to: %d for Initiator"
  		" Node: %s on %s Target Portal Group: %u\n", queue_depth,
  		initiatorname, tpg->se_tpg_tfo->get_fabric_name(),
  		tpg->se_tpg_tfo->tpg_get_tag(tpg));
  
  	spin_lock_irq(&tpg->acl_node_lock);
  	if (dynamic_acl)
  		acl->dynamic_node_acl = 1;
  	spin_unlock_irq(&tpg->acl_node_lock);
  
  	return 0;
  }
  EXPORT_SYMBOL(core_tpg_set_initiator_node_queue_depth);
  
  static int core_tpg_setup_virtual_lun0(struct se_portal_group *se_tpg)
  {
  	/* Set in core_dev_setup_virtual_lun0() */
  	struct se_device *dev = g_lun0_dev;
  	struct se_lun *lun = &se_tpg->tpg_virt_lun0;
  	u32 lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
  	int ret;
  
  	lun->unpacked_lun = 0;
  	lun->lun_status = TRANSPORT_LUN_STATUS_FREE;
  	atomic_set(&lun->lun_acl_count, 0);
  	init_completion(&lun->lun_shutdown_comp);
  	INIT_LIST_HEAD(&lun->lun_acl_list);
  	INIT_LIST_HEAD(&lun->lun_cmd_list);
  	spin_lock_init(&lun->lun_acl_lock);
  	spin_lock_init(&lun->lun_cmd_lock);
  	spin_lock_init(&lun->lun_sep_lock);
  
  	ret = core_tpg_post_addlun(se_tpg, lun, lun_access, dev);
  	if (ret < 0)
  		return ret;
  
  	return 0;
  }
  
  static void core_tpg_release_virtual_lun0(struct se_portal_group *se_tpg)
  {
  	struct se_lun *lun = &se_tpg->tpg_virt_lun0;
  
  	core_tpg_post_dellun(se_tpg, lun);
  }
  
  int core_tpg_register(
  	struct target_core_fabric_ops *tfo,
  	struct se_wwn *se_wwn,
  	struct se_portal_group *se_tpg,
  	void *tpg_fabric_ptr,
  	int se_tpg_type)
  {
  	struct se_lun *lun;
  	u32 i;
  
  	se_tpg->tpg_lun_list = kzalloc((sizeof(struct se_lun) *
  				TRANSPORT_MAX_LUNS_PER_TPG), GFP_KERNEL);
  	if (!se_tpg->tpg_lun_list) {
  		pr_err("Unable to allocate struct se_portal_group->"
  				"tpg_lun_list\n");
  		return -ENOMEM;
  	}
  
  	for (i = 0; i < TRANSPORT_MAX_LUNS_PER_TPG; i++) {
  		lun = &se_tpg->tpg_lun_list[i];
  		lun->unpacked_lun = i;
  		lun->lun_status = TRANSPORT_LUN_STATUS_FREE;
  		atomic_set(&lun->lun_acl_count, 0);
  		init_completion(&lun->lun_shutdown_comp);
  		INIT_LIST_HEAD(&lun->lun_acl_list);
  		INIT_LIST_HEAD(&lun->lun_cmd_list);
  		spin_lock_init(&lun->lun_acl_lock);
  		spin_lock_init(&lun->lun_cmd_lock);
  		spin_lock_init(&lun->lun_sep_lock);
  	}
  
  	se_tpg->se_tpg_type = se_tpg_type;
  	se_tpg->se_tpg_fabric_ptr = tpg_fabric_ptr;
  	se_tpg->se_tpg_tfo = tfo;
  	se_tpg->se_tpg_wwn = se_wwn;
  	atomic_set(&se_tpg->tpg_pr_ref_count, 0);
  	INIT_LIST_HEAD(&se_tpg->acl_node_list);
  	INIT_LIST_HEAD(&se_tpg->se_tpg_node);
  	INIT_LIST_HEAD(&se_tpg->tpg_sess_list);
  	spin_lock_init(&se_tpg->acl_node_lock);
  	spin_lock_init(&se_tpg->session_lock);
  	spin_lock_init(&se_tpg->tpg_lun_lock);
  
  	if (se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL) {
  		if (core_tpg_setup_virtual_lun0(se_tpg) < 0) {
  			kfree(se_tpg);
  			return -ENOMEM;
  		}
  	}
  
  	spin_lock_bh(&tpg_lock);
  	list_add_tail(&se_tpg->se_tpg_node, &tpg_list);
  	spin_unlock_bh(&tpg_lock);
  
  	pr_debug("TARGET_CORE[%s]: Allocated %s struct se_portal_group for"
  		" endpoint: %s, Portal Tag: %u\n", tfo->get_fabric_name(),
  		(se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL) ?
  		"Normal" : "Discovery", (tfo->tpg_get_wwn(se_tpg) == NULL) ?
  		"None" : tfo->tpg_get_wwn(se_tpg), tfo->tpg_get_tag(se_tpg));
  
  	return 0;
  }
  EXPORT_SYMBOL(core_tpg_register);
  
  int core_tpg_deregister(struct se_portal_group *se_tpg)
  {
  	struct se_node_acl *nacl, *nacl_tmp;
  
  	pr_debug("TARGET_CORE[%s]: Deallocating %s struct se_portal_group"
  		" for endpoint: %s Portal Tag %u\n",
  		(se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL) ?
  		"Normal" : "Discovery", se_tpg->se_tpg_tfo->get_fabric_name(),
  		se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
  		se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
  
  	spin_lock_bh(&tpg_lock);
  	list_del(&se_tpg->se_tpg_node);
  	spin_unlock_bh(&tpg_lock);
  
  	while (atomic_read(&se_tpg->tpg_pr_ref_count) != 0)
  		cpu_relax();
  	/*
  	 * Release any remaining demo-mode generated se_node_acl that have
  	 * not been released because of TFO->tpg_check_demo_mode_cache() == 1
  	 * in transport_deregister_session().
  	 */
  	spin_lock_irq(&se_tpg->acl_node_lock);
  	list_for_each_entry_safe(nacl, nacl_tmp, &se_tpg->acl_node_list,
  			acl_list) {
  		list_del(&nacl->acl_list);
  		se_tpg->num_node_acls--;
  		spin_unlock_irq(&se_tpg->acl_node_lock);
  
  		core_tpg_wait_for_nacl_pr_ref(nacl);
  		core_free_device_list_for_node(nacl, se_tpg);
  		se_tpg->se_tpg_tfo->tpg_release_fabric_acl(se_tpg, nacl);
  
  		spin_lock_irq(&se_tpg->acl_node_lock);
  	}
  	spin_unlock_irq(&se_tpg->acl_node_lock);
  
  	if (se_tpg->se_tpg_type == TRANSPORT_TPG_TYPE_NORMAL)
  		core_tpg_release_virtual_lun0(se_tpg);
  
  	se_tpg->se_tpg_fabric_ptr = NULL;
  	kfree(se_tpg->tpg_lun_list);
  	return 0;
  }
  EXPORT_SYMBOL(core_tpg_deregister);
  
  struct se_lun *core_tpg_pre_addlun(
  	struct se_portal_group *tpg,
  	u32 unpacked_lun)
  {
  	struct se_lun *lun;
  
  	if (unpacked_lun > (TRANSPORT_MAX_LUNS_PER_TPG-1)) {
  		pr_err("%s LUN: %u exceeds TRANSPORT_MAX_LUNS_PER_TPG"
  			"-1: %u for Target Portal Group: %u\n",
  			tpg->se_tpg_tfo->get_fabric_name(),
  			unpacked_lun, TRANSPORT_MAX_LUNS_PER_TPG-1,
  			tpg->se_tpg_tfo->tpg_get_tag(tpg));
  		return ERR_PTR(-EOVERFLOW);
  	}
  
  	spin_lock(&tpg->tpg_lun_lock);
  	lun = &tpg->tpg_lun_list[unpacked_lun];
  	if (lun->lun_status == TRANSPORT_LUN_STATUS_ACTIVE) {
  		pr_err("TPG Logical Unit Number: %u is already active"
  			" on %s Target Portal Group: %u, ignoring request.\n",
  			unpacked_lun, tpg->se_tpg_tfo->get_fabric_name(),
  			tpg->se_tpg_tfo->tpg_get_tag(tpg));
  		spin_unlock(&tpg->tpg_lun_lock);
  		return ERR_PTR(-EINVAL);
  	}
  	spin_unlock(&tpg->tpg_lun_lock);
  
  	return lun;
  }
  
  int core_tpg_post_addlun(
  	struct se_portal_group *tpg,
  	struct se_lun *lun,
  	u32 lun_access,
  	void *lun_ptr)
  {
  	int ret;
  
  	ret = core_dev_export(lun_ptr, tpg, lun);
  	if (ret < 0)
  		return ret;
  
  	spin_lock(&tpg->tpg_lun_lock);
  	lun->lun_access = lun_access;
  	lun->lun_status = TRANSPORT_LUN_STATUS_ACTIVE;
  	spin_unlock(&tpg->tpg_lun_lock);
  
  	return 0;
  }
  
  static void core_tpg_shutdown_lun(
  	struct se_portal_group *tpg,
  	struct se_lun *lun)
  {
  	core_clear_lun_from_tpg(lun, tpg);
  	transport_clear_lun_from_sessions(lun);
  }
  
  struct se_lun *core_tpg_pre_dellun(
  	struct se_portal_group *tpg,
  	u32 unpacked_lun)
  {
  	struct se_lun *lun;
  
  	if (unpacked_lun > (TRANSPORT_MAX_LUNS_PER_TPG-1)) {
  		pr_err("%s LUN: %u exceeds TRANSPORT_MAX_LUNS_PER_TPG"
  			"-1: %u for Target Portal Group: %u\n",
  			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,
  			TRANSPORT_MAX_LUNS_PER_TPG-1,
  			tpg->se_tpg_tfo->tpg_get_tag(tpg));
  		return ERR_PTR(-EOVERFLOW);
  	}
  
  	spin_lock(&tpg->tpg_lun_lock);
  	lun = &tpg->tpg_lun_list[unpacked_lun];
  	if (lun->lun_status != TRANSPORT_LUN_STATUS_ACTIVE) {
  		pr_err("%s Logical Unit Number: %u is not active on"
  			" Target Portal Group: %u, ignoring request.\n",
  			tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,
  			tpg->se_tpg_tfo->tpg_get_tag(tpg));
  		spin_unlock(&tpg->tpg_lun_lock);
  		return ERR_PTR(-ENODEV);
  	}
  	spin_unlock(&tpg->tpg_lun_lock);
  
  	return lun;
  }
  
  int core_tpg_post_dellun(
  	struct se_portal_group *tpg,
  	struct se_lun *lun)
  {
  	core_tpg_shutdown_lun(tpg, lun);
  
  	core_dev_unexport(lun->lun_se_dev, tpg, lun);
  
  	spin_lock(&tpg->tpg_lun_lock);
  	lun->lun_status = TRANSPORT_LUN_STATUS_FREE;
  	spin_unlock(&tpg->tpg_lun_lock);
  
  	return 0;
  }
  