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-rw-r--r--drivers/target/target_core_tpg.c679
1 files changed, 679 insertions, 0 deletions
diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
new file mode 100644
index 000000000..02e8a5d86
--- /dev/null
+++ b/drivers/target/target_core_tpg.c
@@ -0,0 +1,679 @@
+/*******************************************************************************
+ * Filename: target_core_tpg.c
+ *
+ * This file contains generic Target Portal Group related functions.
+ *
+ * (c) Copyright 2002-2013 Datera, Inc.
+ *
+ * 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_proto.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
+#include <target/target_core_fabric.h>
+
+#include "target_core_internal.h"
+#include "target_core_alua.h"
+#include "target_core_pr.h"
+#include "target_core_ua.h"
+
+extern struct se_device *g_lun0_dev;
+
+static DEFINE_SPINLOCK(tpg_lock);
+static LIST_HEAD(tpg_list);
+
+/* __core_tpg_get_initiator_node_acl():
+ *
+ * mutex_lock(&tpg->acl_node_mutex); 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;
+ /*
+ * Obtain se_node_acl->acl_kref using fabric driver provided
+ * initiatorname[] during node acl endpoint lookup driven by
+ * new se_session login.
+ *
+ * The reference is held until se_session shutdown -> release
+ * occurs via fabric driver invoked transport_deregister_session()
+ * or transport_free_session() code.
+ */
+ mutex_lock(&tpg->acl_node_mutex);
+ acl = __core_tpg_get_initiator_node_acl(tpg, initiatorname);
+ if (acl) {
+ if (!kref_get_unless_zero(&acl->acl_kref))
+ acl = NULL;
+ }
+ mutex_unlock(&tpg->acl_node_mutex);
+
+ return acl;
+}
+EXPORT_SYMBOL(core_tpg_get_initiator_node_acl);
+
+void core_allocate_nexus_loss_ua(
+ struct se_node_acl *nacl)
+{
+ struct se_dev_entry *deve;
+
+ if (!nacl)
+ return;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
+ core_scsi3_ua_allocate(deve, 0x29,
+ ASCQ_29H_NEXUS_LOSS_OCCURRED);
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(core_allocate_nexus_loss_ua);
+
+/* core_tpg_add_node_to_devs():
+ *
+ *
+ */
+void core_tpg_add_node_to_devs(
+ struct se_node_acl *acl,
+ struct se_portal_group *tpg,
+ struct se_lun *lun_orig)
+{
+ bool lun_access_ro = true;
+ struct se_lun *lun;
+ struct se_device *dev;
+
+ mutex_lock(&tpg->tpg_lun_mutex);
+ hlist_for_each_entry_rcu(lun, &tpg->tpg_lun_hlist, link) {
+ if (lun_orig && lun != lun_orig)
+ continue;
+
+ dev = rcu_dereference_check(lun->lun_se_dev,
+ lockdep_is_held(&tpg->tpg_lun_mutex));
+ /*
+ * 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)) {
+ lun_access_ro = false;
+ } 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_ro = true;
+ else
+ lun_access_ro = false;
+ }
+
+ pr_debug("TARGET_CORE[%s]->TPG[%u]_LUN[%llu] - 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_ro ? "READ-ONLY" : "READ-WRITE");
+
+ core_enable_device_list_for_node(lun, NULL, lun->unpacked_lun,
+ lun_access_ro, acl, tpg);
+ /*
+ * Check to see if there are any existing persistent reservation
+ * APTPL pre-registrations that need to be enabled for this dynamic
+ * LUN ACL now..
+ */
+ core_scsi3_check_aptpl_registration(dev, tpg, lun, acl,
+ lun->unpacked_lun);
+ }
+ mutex_unlock(&tpg->tpg_lun_mutex);
+}
+
+static void
+target_set_nacl_queue_depth(struct se_portal_group *tpg,
+ struct se_node_acl *acl, u32 queue_depth)
+{
+ acl->queue_depth = queue_depth;
+
+ if (!acl->queue_depth) {
+ pr_warn("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;
+ }
+}
+
+static struct se_node_acl *target_alloc_node_acl(struct se_portal_group *tpg,
+ const unsigned char *initiatorname)
+{
+ struct se_node_acl *acl;
+ u32 queue_depth;
+
+ acl = kzalloc(max(sizeof(*acl), tpg->se_tpg_tfo->node_acl_size),
+ GFP_KERNEL);
+ if (!acl)
+ return NULL;
+
+ INIT_LIST_HEAD(&acl->acl_list);
+ INIT_LIST_HEAD(&acl->acl_sess_list);
+ INIT_HLIST_HEAD(&acl->lun_entry_hlist);
+ kref_init(&acl->acl_kref);
+ init_completion(&acl->acl_free_comp);
+ spin_lock_init(&acl->nacl_sess_lock);
+ mutex_init(&acl->lun_entry_mutex);
+ atomic_set(&acl->acl_pr_ref_count, 0);
+
+ if (tpg->se_tpg_tfo->tpg_get_default_depth)
+ queue_depth = tpg->se_tpg_tfo->tpg_get_default_depth(tpg);
+ else
+ queue_depth = 1;
+ target_set_nacl_queue_depth(tpg, acl, 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);
+
+ tpg->se_tpg_tfo->set_default_node_attributes(acl);
+
+ return acl;
+}
+
+static void target_add_node_acl(struct se_node_acl *acl)
+{
+ struct se_portal_group *tpg = acl->se_tpg;
+
+ mutex_lock(&tpg->acl_node_mutex);
+ list_add_tail(&acl->acl_list, &tpg->acl_node_list);
+ mutex_unlock(&tpg->acl_node_mutex);
+
+ pr_debug("%s_TPG[%hu] - Added %s 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->dynamic_node_acl ? "DYNAMIC" : "",
+ acl->queue_depth,
+ tpg->se_tpg_tfo->get_fabric_name(),
+ acl->initiatorname);
+}
+
+bool target_tpg_has_node_acl(struct se_portal_group *tpg,
+ const char *initiatorname)
+{
+ struct se_node_acl *acl;
+ bool found = false;
+
+ mutex_lock(&tpg->acl_node_mutex);
+ list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
+ if (!strcmp(acl->initiatorname, initiatorname)) {
+ found = true;
+ break;
+ }
+ }
+ mutex_unlock(&tpg->acl_node_mutex);
+
+ return found;
+}
+EXPORT_SYMBOL(target_tpg_has_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 = target_alloc_node_acl(tpg, initiatorname);
+ if (!acl)
+ return NULL;
+ /*
+ * When allocating a dynamically generated node_acl, go ahead
+ * and take the extra kref now before returning to the fabric
+ * driver caller.
+ *
+ * Note this reference will be released at session shutdown
+ * time within transport_free_session() code.
+ */
+ kref_get(&acl->acl_kref);
+ acl->dynamic_node_acl = 1;
+
+ /*
+ * Here we only create demo-mode MappedLUNs from the active
+ * TPG LUNs if the fabric is not explicitly 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))
+ core_tpg_add_node_to_devs(acl, tpg, NULL);
+
+ target_add_node_acl(acl);
+ 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();
+}
+
+struct se_node_acl *core_tpg_add_initiator_node_acl(
+ struct se_portal_group *tpg,
+ const char *initiatorname)
+{
+ struct se_node_acl *acl;
+
+ mutex_lock(&tpg->acl_node_mutex);
+ 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);
+ mutex_unlock(&tpg->acl_node_mutex);
+ return acl;
+ }
+
+ 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));
+ mutex_unlock(&tpg->acl_node_mutex);
+ return ERR_PTR(-EEXIST);
+ }
+ mutex_unlock(&tpg->acl_node_mutex);
+
+ acl = target_alloc_node_acl(tpg, initiatorname);
+ if (!acl)
+ return ERR_PTR(-ENOMEM);
+
+ target_add_node_acl(acl);
+ return acl;
+}
+
+static void target_shutdown_sessions(struct se_node_acl *acl)
+{
+ struct se_session *sess;
+ unsigned long flags;
+
+restart:
+ spin_lock_irqsave(&acl->nacl_sess_lock, flags);
+ list_for_each_entry(sess, &acl->acl_sess_list, sess_acl_list) {
+ if (sess->sess_tearing_down)
+ continue;
+
+ list_del_init(&sess->sess_acl_list);
+ spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
+
+ if (acl->se_tpg->se_tpg_tfo->close_session)
+ acl->se_tpg->se_tpg_tfo->close_session(sess);
+ goto restart;
+ }
+ spin_unlock_irqrestore(&acl->nacl_sess_lock, flags);
+}
+
+void core_tpg_del_initiator_node_acl(struct se_node_acl *acl)
+{
+ struct se_portal_group *tpg = acl->se_tpg;
+
+ mutex_lock(&tpg->acl_node_mutex);
+ if (acl->dynamic_node_acl)
+ acl->dynamic_node_acl = 0;
+ list_del_init(&acl->acl_list);
+ mutex_unlock(&tpg->acl_node_mutex);
+
+ target_shutdown_sessions(acl);
+
+ target_put_nacl(acl);
+ /*
+ * Wait for last target_put_nacl() to complete in target_complete_nacl()
+ * for active fabric session transport_deregister_session() callbacks.
+ */
+ wait_for_completion(&acl->acl_free_comp);
+
+ core_tpg_wait_for_nacl_pr_ref(acl);
+ 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);
+
+ kfree(acl);
+}
+
+/* core_tpg_set_initiator_node_queue_depth():
+ *
+ *
+ */
+int core_tpg_set_initiator_node_queue_depth(
+ struct se_node_acl *acl,
+ u32 queue_depth)
+{
+ struct se_portal_group *tpg = acl->se_tpg;
+
+ /*
+ * Allow the setting of se_node_acl queue_depth to be idempotent,
+ * and not force a session shutdown event if the value is not
+ * changing.
+ */
+ if (acl->queue_depth == queue_depth)
+ return 0;
+ /*
+ * 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
+ * target_set_nacl_queue_depth() to set the new queue depth.
+ */
+ target_set_nacl_queue_depth(tpg, acl, queue_depth);
+
+ /*
+ * Shutdown all pending sessions to force session reinstatement.
+ */
+ target_shutdown_sessions(acl);
+
+ pr_debug("Successfully changed queue depth to: %d for Initiator"
+ " Node: %s on %s Target Portal Group: %u\n", acl->queue_depth,
+ acl->initiatorname, tpg->se_tpg_tfo->get_fabric_name(),
+ tpg->se_tpg_tfo->tpg_get_tag(tpg));
+
+ return 0;
+}
+EXPORT_SYMBOL(core_tpg_set_initiator_node_queue_depth);
+
+/* core_tpg_set_initiator_node_tag():
+ *
+ * Initiator nodeacl tags are not used internally, but may be used by
+ * userspace to emulate aliases or groups.
+ * Returns length of newly-set tag or -EINVAL.
+ */
+int core_tpg_set_initiator_node_tag(
+ struct se_portal_group *tpg,
+ struct se_node_acl *acl,
+ const char *new_tag)
+{
+ if (strlen(new_tag) >= MAX_ACL_TAG_SIZE)
+ return -EINVAL;
+
+ if (!strncmp("NULL", new_tag, 4)) {
+ acl->acl_tag[0] = '\0';
+ return 0;
+ }
+
+ return snprintf(acl->acl_tag, MAX_ACL_TAG_SIZE, "%s", new_tag);
+}
+EXPORT_SYMBOL(core_tpg_set_initiator_node_tag);
+
+static void core_tpg_lun_ref_release(struct percpu_ref *ref)
+{
+ struct se_lun *lun = container_of(ref, struct se_lun, lun_ref);
+
+ complete(&lun->lun_shutdown_comp);
+}
+
+/* Does not change se_wwn->priv. */
+int core_tpg_register(
+ struct se_wwn *se_wwn,
+ struct se_portal_group *se_tpg,
+ int proto_id)
+{
+ int ret;
+
+ if (!se_tpg)
+ return -EINVAL;
+ /*
+ * For the typical case where core_tpg_register() is called by a
+ * fabric driver from target_core_fabric_ops->fabric_make_tpg()
+ * configfs context, use the original tf_ops pointer already saved
+ * by target-core in target_fabric_make_wwn().
+ *
+ * Otherwise, for special cases like iscsi-target discovery TPGs
+ * the caller is responsible for setting ->se_tpg_tfo ahead of
+ * calling core_tpg_register().
+ */
+ if (se_wwn)
+ se_tpg->se_tpg_tfo = se_wwn->wwn_tf->tf_ops;
+
+ if (!se_tpg->se_tpg_tfo) {
+ pr_err("Unable to locate se_tpg->se_tpg_tfo pointer\n");
+ return -EINVAL;
+ }
+
+ INIT_HLIST_HEAD(&se_tpg->tpg_lun_hlist);
+ se_tpg->proto_id = proto_id;
+ 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->session_lock);
+ mutex_init(&se_tpg->tpg_lun_mutex);
+ mutex_init(&se_tpg->acl_node_mutex);
+
+ if (se_tpg->proto_id >= 0) {
+ se_tpg->tpg_virt_lun0 = core_tpg_alloc_lun(se_tpg, 0);
+ if (IS_ERR(se_tpg->tpg_virt_lun0))
+ return PTR_ERR(se_tpg->tpg_virt_lun0);
+
+ ret = core_tpg_add_lun(se_tpg, se_tpg->tpg_virt_lun0,
+ true, g_lun0_dev);
+ if (ret < 0) {
+ kfree(se_tpg->tpg_virt_lun0);
+ return ret;
+ }
+ }
+
+ 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 portal_group for endpoint: %s, "
+ "Proto: %d, Portal Tag: %u\n", 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_wwn(se_tpg) : NULL,
+ se_tpg->proto_id, se_tpg->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)
+{
+ const struct target_core_fabric_ops *tfo = se_tpg->se_tpg_tfo;
+ struct se_node_acl *nacl, *nacl_tmp;
+ LIST_HEAD(node_list);
+
+ pr_debug("TARGET_CORE[%s]: Deallocating portal_group for endpoint: %s, "
+ "Proto: %d, Portal Tag: %u\n", tfo->get_fabric_name(),
+ tfo->tpg_get_wwn(se_tpg) ? tfo->tpg_get_wwn(se_tpg) : NULL,
+ se_tpg->proto_id, 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();
+
+ mutex_lock(&se_tpg->acl_node_mutex);
+ list_splice_init(&se_tpg->acl_node_list, &node_list);
+ mutex_unlock(&se_tpg->acl_node_mutex);
+ /*
+ * 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().
+ */
+ list_for_each_entry_safe(nacl, nacl_tmp, &node_list, acl_list) {
+ list_del_init(&nacl->acl_list);
+
+ core_tpg_wait_for_nacl_pr_ref(nacl);
+ core_free_device_list_for_node(nacl, se_tpg);
+ kfree(nacl);
+ }
+
+ if (se_tpg->proto_id >= 0) {
+ core_tpg_remove_lun(se_tpg, se_tpg->tpg_virt_lun0);
+ kfree_rcu(se_tpg->tpg_virt_lun0, rcu_head);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(core_tpg_deregister);
+
+struct se_lun *core_tpg_alloc_lun(
+ struct se_portal_group *tpg,
+ u64 unpacked_lun)
+{
+ struct se_lun *lun;
+
+ lun = kzalloc(sizeof(*lun), GFP_KERNEL);
+ if (!lun) {
+ pr_err("Unable to allocate se_lun memory\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ lun->unpacked_lun = unpacked_lun;
+ atomic_set(&lun->lun_acl_count, 0);
+ init_completion(&lun->lun_ref_comp);
+ init_completion(&lun->lun_shutdown_comp);
+ INIT_LIST_HEAD(&lun->lun_deve_list);
+ INIT_LIST_HEAD(&lun->lun_dev_link);
+ atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
+ spin_lock_init(&lun->lun_deve_lock);
+ mutex_init(&lun->lun_tg_pt_md_mutex);
+ INIT_LIST_HEAD(&lun->lun_tg_pt_gp_link);
+ spin_lock_init(&lun->lun_tg_pt_gp_lock);
+ lun->lun_tpg = tpg;
+
+ return lun;
+}
+
+int core_tpg_add_lun(
+ struct se_portal_group *tpg,
+ struct se_lun *lun,
+ bool lun_access_ro,
+ struct se_device *dev)
+{
+ int ret;
+
+ ret = percpu_ref_init(&lun->lun_ref, core_tpg_lun_ref_release, 0,
+ GFP_KERNEL);
+ if (ret < 0)
+ goto out;
+
+ ret = core_alloc_rtpi(lun, dev);
+ if (ret)
+ goto out_kill_ref;
+
+ if (!(dev->transport->transport_flags &
+ TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
+ !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
+ target_attach_tg_pt_gp(lun, dev->t10_alua.default_tg_pt_gp);
+
+ mutex_lock(&tpg->tpg_lun_mutex);
+
+ spin_lock(&dev->se_port_lock);
+ lun->lun_index = dev->dev_index;
+ rcu_assign_pointer(lun->lun_se_dev, dev);
+ dev->export_count++;
+ list_add_tail(&lun->lun_dev_link, &dev->dev_sep_list);
+ spin_unlock(&dev->se_port_lock);
+
+ if (dev->dev_flags & DF_READ_ONLY)
+ lun->lun_access_ro = true;
+ else
+ lun->lun_access_ro = lun_access_ro;
+ if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
+ hlist_add_head_rcu(&lun->link, &tpg->tpg_lun_hlist);
+ mutex_unlock(&tpg->tpg_lun_mutex);
+
+ return 0;
+
+out_kill_ref:
+ percpu_ref_exit(&lun->lun_ref);
+out:
+ return ret;
+}
+
+void core_tpg_remove_lun(
+ struct se_portal_group *tpg,
+ struct se_lun *lun)
+{
+ /*
+ * rcu_dereference_raw protected by se_lun->lun_group symlink
+ * reference to se_device->dev_group.
+ */
+ struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
+
+ lun->lun_shutdown = true;
+
+ core_clear_lun_from_tpg(lun, tpg);
+ /*
+ * Wait for any active I/O references to percpu se_lun->lun_ref to
+ * be released. Also, se_lun->lun_ref is now used by PR and ALUA
+ * logic when referencing a remote target port during ALL_TGT_PT=1
+ * and generating UNIT_ATTENTIONs for ALUA access state transition.
+ */
+ transport_clear_lun_ref(lun);
+
+ mutex_lock(&tpg->tpg_lun_mutex);
+ if (lun->lun_se_dev) {
+ target_detach_tg_pt_gp(lun);
+
+ spin_lock(&dev->se_port_lock);
+ list_del(&lun->lun_dev_link);
+ dev->export_count--;
+ rcu_assign_pointer(lun->lun_se_dev, NULL);
+ spin_unlock(&dev->se_port_lock);
+ }
+ if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
+ hlist_del_rcu(&lun->link);
+
+ lun->lun_shutdown = false;
+ mutex_unlock(&tpg->tpg_lun_mutex);
+
+ percpu_ref_exit(&lun->lun_ref);
+}