]> git.karo-electronics.de Git - mv-sheeva.git/blobdiff - drivers/target/target_core_alua.c
Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[mv-sheeva.git] / drivers / target / target_core_alua.c
diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c
new file mode 100644 (file)
index 0000000..2c5fcfe
--- /dev/null
@@ -0,0 +1,1991 @@
+/*******************************************************************************
+ * Filename:  target_core_alua.c
+ *
+ * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
+ *
+ * Copyright (c) 2009-2010 Rising Tide Systems
+ * Copyright (c) 2009-2010 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/version.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/configfs.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <target/target_core_base.h>
+#include <target/target_core_device.h>
+#include <target/target_core_transport.h>
+#include <target/target_core_fabric_ops.h>
+#include <target/target_core_configfs.h>
+
+#include "target_core_alua.h"
+#include "target_core_hba.h"
+#include "target_core_ua.h"
+
+static int core_alua_check_transition(int state, int *primary);
+static int core_alua_set_tg_pt_secondary_state(
+               struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+               struct se_port *port, int explict, int offline);
+
+/*
+ * REPORT_TARGET_PORT_GROUPS
+ *
+ * See spc4r17 section 6.27
+ */
+int core_emulate_report_target_port_groups(struct se_cmd *cmd)
+{
+       struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
+       struct se_port *port;
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+       unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
+       u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
+                                   Target port group descriptor */
+
+       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
+                       tg_pt_gp_list) {
+               /*
+                * PREF: Preferred target port bit, determine if this
+                * bit should be set for port group.
+                */
+               if (tg_pt_gp->tg_pt_gp_pref)
+                       buf[off] = 0x80;
+               /*
+                * Set the ASYMMETRIC ACCESS State
+                */
+               buf[off++] |= (atomic_read(
+                       &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
+               /*
+                * Set supported ASYMMETRIC ACCESS State bits
+                */
+               buf[off] = 0x80; /* T_SUP */
+               buf[off] |= 0x40; /* O_SUP */
+               buf[off] |= 0x8; /* U_SUP */
+               buf[off] |= 0x4; /* S_SUP */
+               buf[off] |= 0x2; /* AN_SUP */
+               buf[off++] |= 0x1; /* AO_SUP */
+               /*
+                * TARGET PORT GROUP
+                */
+               buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
+               buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
+
+               off++; /* Skip over Reserved */
+               /*
+                * STATUS CODE
+                */
+               buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
+               /*
+                * Vendor Specific field
+                */
+               buf[off++] = 0x00;
+               /*
+                * TARGET PORT COUNT
+                */
+               buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
+               rd_len += 8;
+
+               spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+               list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
+                               tg_pt_gp_mem_list) {
+                       port = tg_pt_gp_mem->tg_pt;
+                       /*
+                        * Start Target Port descriptor format
+                        *
+                        * See spc4r17 section 6.2.7 Table 247
+                        */
+                       off += 2; /* Skip over Obsolete */
+                       /*
+                        * Set RELATIVE TARGET PORT IDENTIFIER
+                        */
+                       buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
+                       buf[off++] = (port->sep_rtpi & 0xff);
+                       rd_len += 4;
+               }
+               spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+       }
+       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       /*
+        * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
+        */
+       buf[0] = ((rd_len >> 24) & 0xff);
+       buf[1] = ((rd_len >> 16) & 0xff);
+       buf[2] = ((rd_len >> 8) & 0xff);
+       buf[3] = (rd_len & 0xff);
+
+       return 0;
+}
+
+/*
+ * SET_TARGET_PORT_GROUPS for explict ALUA operation.
+ *
+ * See spc4r17 section 6.35
+ */
+int core_emulate_set_target_port_groups(struct se_cmd *cmd)
+{
+       struct se_device *dev = SE_DEV(cmd);
+       struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
+       struct se_port *port, *l_port = SE_LUN(cmd)->lun_sep;
+       struct se_node_acl *nacl = SE_SESS(cmd)->se_node_acl;
+       struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
+       unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
+       unsigned char *ptr = &buf[4]; /* Skip over RESERVED area in header */
+       u32 len = 4; /* Skip over RESERVED area in header */
+       int alua_access_state, primary = 0, rc;
+       u16 tg_pt_id, rtpi;
+
+       if (!(l_port))
+               return PYX_TRANSPORT_LU_COMM_FAILURE;
+       /*
+        * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
+        * for the local tg_pt_gp.
+        */
+       l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
+       if (!(l_tg_pt_gp_mem)) {
+               printk(KERN_ERR "Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
+               return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+       }
+       spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
+       if (!(l_tg_pt_gp)) {
+               spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
+               printk(KERN_ERR "Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
+               return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+       }
+       rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
+       spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+       if (!(rc)) {
+               printk(KERN_INFO "Unable to process SET_TARGET_PORT_GROUPS"
+                               " while TPGS_EXPLICT_ALUA is disabled\n");
+               return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
+       }
+
+       while (len < cmd->data_length) {
+               alua_access_state = (ptr[0] & 0x0f);
+               /*
+                * Check the received ALUA access state, and determine if
+                * the state is a primary or secondary target port asymmetric
+                * access state.
+                */
+               rc = core_alua_check_transition(alua_access_state, &primary);
+               if (rc != 0) {
+                       /*
+                        * If the SET TARGET PORT GROUPS attempts to establish
+                        * an invalid combination of target port asymmetric
+                        * access states or attempts to establish an
+                        * unsupported target port asymmetric access state,
+                        * then the command shall be terminated with CHECK
+                        * CONDITION status, with the sense key set to ILLEGAL
+                        * REQUEST, and the additional sense code set to INVALID
+                        * FIELD IN PARAMETER LIST.
+                        */
+                       return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+               }
+               rc = -1;
+               /*
+                * If the ASYMMETRIC ACCESS STATE field (see table 267)
+                * specifies a primary target port asymmetric access state,
+                * then the TARGET PORT GROUP OR TARGET PORT field specifies
+                * a primary target port group for which the primary target
+                * port asymmetric access state shall be changed. If the
+                * ASYMMETRIC ACCESS STATE field specifies a secondary target
+                * port asymmetric access state, then the TARGET PORT GROUP OR
+                * TARGET PORT field specifies the relative target port
+                * identifier (see 3.1.120) of the target port for which the
+                * secondary target port asymmetric access state shall be
+                * changed.
+                */
+               if (primary) {
+                       tg_pt_id = ((ptr[2] << 8) & 0xff);
+                       tg_pt_id |= (ptr[3] & 0xff);
+                       /*
+                        * Locate the matching target port group ID from
+                        * the global tg_pt_gp list
+                        */
+                       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                       list_for_each_entry(tg_pt_gp,
+                                       &T10_ALUA(su_dev)->tg_pt_gps_list,
+                                       tg_pt_gp_list) {
+                               if (!(tg_pt_gp->tg_pt_gp_valid_id))
+                                       continue;
+
+                               if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
+                                       continue;
+
+                               atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
+                               smp_mb__after_atomic_inc();
+                               spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+                               rc = core_alua_do_port_transition(tg_pt_gp,
+                                               dev, l_port, nacl,
+                                               alua_access_state, 1);
+
+                               spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                               atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
+                               smp_mb__after_atomic_dec();
+                               break;
+                       }
+                       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                       /*
+                        * If not matching target port group ID can be located
+                        * throw an exception with ASCQ: INVALID_PARAMETER_LIST
+                        */
+                       if (rc != 0)
+                               return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+               } else {
+                       /*
+                        * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
+                        * the Target Port in question for the the incoming
+                        * SET_TARGET_PORT_GROUPS op.
+                        */
+                       rtpi = ((ptr[2] << 8) & 0xff);
+                       rtpi |= (ptr[3] & 0xff);
+                       /*
+                        * Locate the matching relative target port identifer
+                        * for the struct se_device storage object.
+                        */
+                       spin_lock(&dev->se_port_lock);
+                       list_for_each_entry(port, &dev->dev_sep_list,
+                                                       sep_list) {
+                               if (port->sep_rtpi != rtpi)
+                                       continue;
+
+                               tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+                               spin_unlock(&dev->se_port_lock);
+
+                               rc = core_alua_set_tg_pt_secondary_state(
+                                               tg_pt_gp_mem, port, 1, 1);
+
+                               spin_lock(&dev->se_port_lock);
+                               break;
+                       }
+                       spin_unlock(&dev->se_port_lock);
+                       /*
+                        * If not matching relative target port identifier can
+                        * be located, throw an exception with ASCQ:
+                        * INVALID_PARAMETER_LIST
+                        */
+                       if (rc != 0)
+                               return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
+               }
+
+               ptr += 4;
+               len += 4;
+       }
+
+       return 0;
+}
+
+static inline int core_alua_state_nonoptimized(
+       struct se_cmd *cmd,
+       unsigned char *cdb,
+       int nonop_delay_msecs,
+       u8 *alua_ascq)
+{
+       /*
+        * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
+        * later to determine if processing of this cmd needs to be
+        * temporarily delayed for the Active/NonOptimized primary access state.
+        */
+       cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
+       cmd->alua_nonop_delay = nonop_delay_msecs;
+       return 0;
+}
+
+static inline int core_alua_state_standby(
+       struct se_cmd *cmd,
+       unsigned char *cdb,
+       u8 *alua_ascq)
+{
+       /*
+        * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
+        * spc4r17 section 5.9.2.4.4
+        */
+       switch (cdb[0]) {
+       case INQUIRY:
+       case LOG_SELECT:
+       case LOG_SENSE:
+       case MODE_SELECT:
+       case MODE_SENSE:
+       case REPORT_LUNS:
+       case RECEIVE_DIAGNOSTIC:
+       case SEND_DIAGNOSTIC:
+       case MAINTENANCE_IN:
+               switch (cdb[1]) {
+               case MI_REPORT_TARGET_PGS:
+                       return 0;
+               default:
+                       *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
+                       return 1;
+               }
+       case MAINTENANCE_OUT:
+               switch (cdb[1]) {
+               case MO_SET_TARGET_PGS:
+                       return 0;
+               default:
+                       *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
+                       return 1;
+               }
+       case REQUEST_SENSE:
+       case PERSISTENT_RESERVE_IN:
+       case PERSISTENT_RESERVE_OUT:
+       case READ_BUFFER:
+       case WRITE_BUFFER:
+               return 0;
+       default:
+               *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
+               return 1;
+       }
+
+       return 0;
+}
+
+static inline int core_alua_state_unavailable(
+       struct se_cmd *cmd,
+       unsigned char *cdb,
+       u8 *alua_ascq)
+{
+       /*
+        * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
+        * spc4r17 section 5.9.2.4.5
+        */
+       switch (cdb[0]) {
+       case INQUIRY:
+       case REPORT_LUNS:
+       case MAINTENANCE_IN:
+               switch (cdb[1]) {
+               case MI_REPORT_TARGET_PGS:
+                       return 0;
+               default:
+                       *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
+                       return 1;
+               }
+       case MAINTENANCE_OUT:
+               switch (cdb[1]) {
+               case MO_SET_TARGET_PGS:
+                       return 0;
+               default:
+                       *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
+                       return 1;
+               }
+       case REQUEST_SENSE:
+       case READ_BUFFER:
+       case WRITE_BUFFER:
+               return 0;
+       default:
+               *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
+               return 1;
+       }
+
+       return 0;
+}
+
+static inline int core_alua_state_transition(
+       struct se_cmd *cmd,
+       unsigned char *cdb,
+       u8 *alua_ascq)
+{
+       /*
+        * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
+        * spc4r17 section 5.9.2.5
+        */
+       switch (cdb[0]) {
+       case INQUIRY:
+       case REPORT_LUNS:
+       case MAINTENANCE_IN:
+               switch (cdb[1]) {
+               case MI_REPORT_TARGET_PGS:
+                       return 0;
+               default:
+                       *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
+                       return 1;
+               }
+       case REQUEST_SENSE:
+       case READ_BUFFER:
+       case WRITE_BUFFER:
+               return 0;
+       default:
+               *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
+               return 1;
+       }
+
+       return 0;
+}
+
+/*
+ * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
+ * in transport_cmd_sequencer().  This function is assigned to
+ * struct t10_alua *->state_check() in core_setup_alua()
+ */
+static int core_alua_state_check_nop(
+       struct se_cmd *cmd,
+       unsigned char *cdb,
+       u8 *alua_ascq)
+{
+       return 0;
+}
+
+/*
+ * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
+ * This function is assigned to struct t10_alua *->state_check() in
+ * core_setup_alua()
+ *
+ * Also, this function can return three different return codes to
+ * signal transport_generic_cmd_sequencer()
+ *
+ * return 1: Is used to signal LUN not accecsable, and check condition/not ready
+ * return 0: Used to signal success
+ * reutrn -1: Used to signal failure, and invalid cdb field
+ */
+static int core_alua_state_check(
+       struct se_cmd *cmd,
+       unsigned char *cdb,
+       u8 *alua_ascq)
+{
+       struct se_lun *lun = SE_LUN(cmd);
+       struct se_port *port = lun->lun_sep;
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+       int out_alua_state, nonop_delay_msecs;
+
+       if (!(port))
+               return 0;
+       /*
+        * First, check for a struct se_port specific secondary ALUA target port
+        * access state: OFFLINE
+        */
+       if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
+               *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
+               printk(KERN_INFO "ALUA: Got secondary offline status for local"
+                               " target port\n");
+               *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
+               return 1;
+       }
+        /*
+        * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
+        * ALUA target port group, to obtain current ALUA access state.
+        * Otherwise look for the underlying struct se_device association with
+        * a ALUA logical unit group.
+        */
+       tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+       spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+       out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
+       nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
+       spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       /*
+        * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a seperate conditional
+        * statement so the complier knows explictly to check this case first.
+        * For the Optimized ALUA access state case, we want to process the
+        * incoming fabric cmd ASAP..
+        */
+       if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
+               return 0;
+
+       switch (out_alua_state) {
+       case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
+               return core_alua_state_nonoptimized(cmd, cdb,
+                                       nonop_delay_msecs, alua_ascq);
+       case ALUA_ACCESS_STATE_STANDBY:
+               return core_alua_state_standby(cmd, cdb, alua_ascq);
+       case ALUA_ACCESS_STATE_UNAVAILABLE:
+               return core_alua_state_unavailable(cmd, cdb, alua_ascq);
+       case ALUA_ACCESS_STATE_TRANSITION:
+               return core_alua_state_transition(cmd, cdb, alua_ascq);
+       /*
+        * OFFLINE is a secondary ALUA target port group access state, that is
+        * handled above with struct se_port->sep_tg_pt_secondary_offline=1
+        */
+       case ALUA_ACCESS_STATE_OFFLINE:
+       default:
+               printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n",
+                               out_alua_state);
+               return -1;
+       }
+
+       return 0;
+}
+
+/*
+ * Check implict and explict ALUA state change request.
+ */
+static int core_alua_check_transition(int state, int *primary)
+{
+       switch (state) {
+       case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
+       case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
+       case ALUA_ACCESS_STATE_STANDBY:
+       case ALUA_ACCESS_STATE_UNAVAILABLE:
+               /*
+                * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
+                * defined as primary target port asymmetric access states.
+                */
+               *primary = 1;
+               break;
+       case ALUA_ACCESS_STATE_OFFLINE:
+               /*
+                * OFFLINE state is defined as a secondary target port
+                * asymmetric access state.
+                */
+               *primary = 0;
+               break;
+       default:
+               printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n", state);
+               return -1;
+       }
+
+       return 0;
+}
+
+static char *core_alua_dump_state(int state)
+{
+       switch (state) {
+       case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
+               return "Active/Optimized";
+       case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
+               return "Active/NonOptimized";
+       case ALUA_ACCESS_STATE_STANDBY:
+               return "Standby";
+       case ALUA_ACCESS_STATE_UNAVAILABLE:
+               return "Unavailable";
+       case ALUA_ACCESS_STATE_OFFLINE:
+               return "Offline";
+       default:
+               return "Unknown";
+       }
+
+       return NULL;
+}
+
+char *core_alua_dump_status(int status)
+{
+       switch (status) {
+       case ALUA_STATUS_NONE:
+               return "None";
+       case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
+               return "Altered by Explict STPG";
+       case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
+               return "Altered by Implict ALUA";
+       default:
+               return "Unknown";
+       }
+
+       return NULL;
+}
+
+/*
+ * Used by fabric modules to determine when we need to delay processing
+ * for the Active/NonOptimized paths..
+ */
+int core_alua_check_nonop_delay(
+       struct se_cmd *cmd)
+{
+       if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
+               return 0;
+       if (in_interrupt())
+               return 0;
+       /*
+        * The ALUA Active/NonOptimized access state delay can be disabled
+        * in via configfs with a value of zero
+        */
+       if (!(cmd->alua_nonop_delay))
+               return 0;
+       /*
+        * struct se_cmd->alua_nonop_delay gets set by a target port group
+        * defined interval in core_alua_state_nonoptimized()
+        */
+       msleep_interruptible(cmd->alua_nonop_delay);
+       return 0;
+}
+EXPORT_SYMBOL(core_alua_check_nonop_delay);
+
+/*
+ * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
+ *
+ */
+static int core_alua_write_tpg_metadata(
+       const char *path,
+       unsigned char *md_buf,
+       u32 md_buf_len)
+{
+       mm_segment_t old_fs;
+       struct file *file;
+       struct iovec iov[1];
+       int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
+
+       memset(iov, 0, sizeof(struct iovec));
+
+       file = filp_open(path, flags, 0600);
+       if (IS_ERR(file) || !file || !file->f_dentry) {
+               printk(KERN_ERR "filp_open(%s) for ALUA metadata failed\n",
+                       path);
+               return -ENODEV;
+       }
+
+       iov[0].iov_base = &md_buf[0];
+       iov[0].iov_len = md_buf_len;
+
+       old_fs = get_fs();
+       set_fs(get_ds());
+       ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
+       set_fs(old_fs);
+
+       if (ret < 0) {
+               printk(KERN_ERR "Error writing ALUA metadata file: %s\n", path);
+               filp_close(file, NULL);
+               return -EIO;
+       }
+       filp_close(file, NULL);
+
+       return 0;
+}
+
+/*
+ * Called with tg_pt_gp->tg_pt_gp_md_mutex held
+ */
+static int core_alua_update_tpg_primary_metadata(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       int primary_state,
+       unsigned char *md_buf)
+{
+       struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+       struct t10_wwn *wwn = &su_dev->t10_wwn;
+       char path[ALUA_METADATA_PATH_LEN];
+       int len;
+
+       memset(path, 0, ALUA_METADATA_PATH_LEN);
+
+       len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
+                       "tg_pt_gp_id=%hu\n"
+                       "alua_access_state=0x%02x\n"
+                       "alua_access_status=0x%02x\n",
+                       tg_pt_gp->tg_pt_gp_id, primary_state,
+                       tg_pt_gp->tg_pt_gp_alua_access_status);
+
+       snprintf(path, ALUA_METADATA_PATH_LEN,
+               "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
+               config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
+
+       return core_alua_write_tpg_metadata(path, md_buf, len);
+}
+
+static int core_alua_do_transition_tg_pt(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       struct se_port *l_port,
+       struct se_node_acl *nacl,
+       unsigned char *md_buf,
+       int new_state,
+       int explict)
+{
+       struct se_dev_entry *se_deve;
+       struct se_lun_acl *lacl;
+       struct se_port *port;
+       struct t10_alua_tg_pt_gp_member *mem;
+       int old_state = 0;
+       /*
+        * Save the old primary ALUA access state, and set the current state
+        * to ALUA_ACCESS_STATE_TRANSITION.
+        */
+       old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
+       atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
+                       ALUA_ACCESS_STATE_TRANSITION);
+       tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
+                               ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
+                               ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
+       /*
+        * Check for the optional ALUA primary state transition delay
+        */
+       if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
+               msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
+
+       spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+       list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
+                               tg_pt_gp_mem_list) {
+               port = mem->tg_pt;
+               /*
+                * After an implicit target port asymmetric access state
+                * change, a device server shall establish a unit attention
+                * condition for the initiator port associated with every I_T
+                * nexus with the additional sense code set to ASYMMETRIC
+                * ACCESS STATE CHAGED.
+                *
+                * After an explicit target port asymmetric access state
+                * change, a device server shall establish a unit attention
+                * condition with the additional sense code set to ASYMMETRIC
+                * ACCESS STATE CHANGED for the initiator port associated with
+                * every I_T nexus other than the I_T nexus on which the SET
+                * TARGET PORT GROUPS command
+                */
+               atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
+               smp_mb__after_atomic_inc();
+               spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+
+               spin_lock_bh(&port->sep_alua_lock);
+               list_for_each_entry(se_deve, &port->sep_alua_list,
+                                       alua_port_list) {
+                       lacl = se_deve->se_lun_acl;
+                       /*
+                        * se_deve->se_lun_acl pointer may be NULL for a
+                        * entry created without explict Node+MappedLUN ACLs
+                        */
+                       if (!(lacl))
+                               continue;
+
+                       if (explict &&
+                          (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
+                          (l_port != NULL) && (l_port == port))
+                               continue;
+
+                       core_scsi3_ua_allocate(lacl->se_lun_nacl,
+                               se_deve->mapped_lun, 0x2A,
+                               ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
+               }
+               spin_unlock_bh(&port->sep_alua_lock);
+
+               spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+               atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
+               smp_mb__after_atomic_dec();
+       }
+       spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+       /*
+        * Update the ALUA metadata buf that has been allocated in
+        * core_alua_do_port_transition(), this metadata will be written
+        * to struct file.
+        *
+        * Note that there is the case where we do not want to update the
+        * metadata when the saved metadata is being parsed in userspace
+        * when setting the existing port access state and access status.
+        *
+        * Also note that the failure to write out the ALUA metadata to
+        * struct file does NOT affect the actual ALUA transition.
+        */
+       if (tg_pt_gp->tg_pt_gp_write_metadata) {
+               mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
+               core_alua_update_tpg_primary_metadata(tg_pt_gp,
+                                       new_state, md_buf);
+               mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
+       }
+       /*
+        * Set the current primary ALUA access state to the requested new state
+        */
+       atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
+
+       printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
+               " from primary access state %s to %s\n", (explict) ? "explict" :
+               "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
+               tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
+               core_alua_dump_state(new_state));
+
+       return 0;
+}
+
+int core_alua_do_port_transition(
+       struct t10_alua_tg_pt_gp *l_tg_pt_gp,
+       struct se_device *l_dev,
+       struct se_port *l_port,
+       struct se_node_acl *l_nacl,
+       int new_state,
+       int explict)
+{
+       struct se_device *dev;
+       struct se_port *port;
+       struct se_subsystem_dev *su_dev;
+       struct se_node_acl *nacl;
+       struct t10_alua_lu_gp *lu_gp;
+       struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       unsigned char *md_buf;
+       int primary;
+
+       if (core_alua_check_transition(new_state, &primary) != 0)
+               return -EINVAL;
+
+       md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
+       if (!(md_buf)) {
+               printk("Unable to allocate buf for ALUA metadata\n");
+               return -ENOMEM;
+       }
+
+       local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
+       spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
+       lu_gp = local_lu_gp_mem->lu_gp;
+       atomic_inc(&lu_gp->lu_gp_ref_cnt);
+       smp_mb__after_atomic_inc();
+       spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
+       /*
+        * For storage objects that are members of the 'default_lu_gp',
+        * we only do transition on the passed *l_tp_pt_gp, and not
+        * on all of the matching target port groups IDs in default_lu_gp.
+        */
+       if (!(lu_gp->lu_gp_id)) {
+               /*
+                * core_alua_do_transition_tg_pt() will always return
+                * success.
+                */
+               core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
+                                       md_buf, new_state, explict);
+               atomic_dec(&lu_gp->lu_gp_ref_cnt);
+               smp_mb__after_atomic_dec();
+               kfree(md_buf);
+               return 0;
+       }
+       /*
+        * For all other LU groups aside from 'default_lu_gp', walk all of
+        * the associated storage objects looking for a matching target port
+        * group ID from the local target port group.
+        */
+       spin_lock(&lu_gp->lu_gp_lock);
+       list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
+                               lu_gp_mem_list) {
+
+               dev = lu_gp_mem->lu_gp_mem_dev;
+               su_dev = dev->se_sub_dev;
+               atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
+               smp_mb__after_atomic_inc();
+               spin_unlock(&lu_gp->lu_gp_lock);
+
+               spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+               list_for_each_entry(tg_pt_gp,
+                               &T10_ALUA(su_dev)->tg_pt_gps_list,
+                               tg_pt_gp_list) {
+
+                       if (!(tg_pt_gp->tg_pt_gp_valid_id))
+                               continue;
+                       /*
+                        * If the target behavior port asymmetric access state
+                        * is changed for any target port group accessiable via
+                        * a logical unit within a LU group, the target port
+                        * behavior group asymmetric access states for the same
+                        * target port group accessible via other logical units
+                        * in that LU group will also change.
+                        */
+                       if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
+                               continue;
+
+                       if (l_tg_pt_gp == tg_pt_gp) {
+                               port = l_port;
+                               nacl = l_nacl;
+                       } else {
+                               port = NULL;
+                               nacl = NULL;
+                       }
+                       atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
+                       smp_mb__after_atomic_inc();
+                       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                       /*
+                        * core_alua_do_transition_tg_pt() will always return
+                        * success.
+                        */
+                       core_alua_do_transition_tg_pt(tg_pt_gp, port,
+                                       nacl, md_buf, new_state, explict);
+
+                       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                       atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
+                       smp_mb__after_atomic_dec();
+               }
+               spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+               spin_lock(&lu_gp->lu_gp_lock);
+               atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
+               smp_mb__after_atomic_dec();
+       }
+       spin_unlock(&lu_gp->lu_gp_lock);
+
+       printk(KERN_INFO "Successfully processed LU Group: %s all ALUA TG PT"
+               " Group IDs: %hu %s transition to primary state: %s\n",
+               config_item_name(&lu_gp->lu_gp_group.cg_item),
+               l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
+               core_alua_dump_state(new_state));
+
+       atomic_dec(&lu_gp->lu_gp_ref_cnt);
+       smp_mb__after_atomic_dec();
+       kfree(md_buf);
+       return 0;
+}
+
+/*
+ * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
+ */
+static int core_alua_update_tpg_secondary_metadata(
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+       struct se_port *port,
+       unsigned char *md_buf,
+       u32 md_buf_len)
+{
+       struct se_portal_group *se_tpg = port->sep_tpg;
+       char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
+       int len;
+
+       memset(path, 0, ALUA_METADATA_PATH_LEN);
+       memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
+
+       len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
+                       TPG_TFO(se_tpg)->tpg_get_wwn(se_tpg));
+
+       if (TPG_TFO(se_tpg)->tpg_get_tag != NULL)
+               snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
+                               TPG_TFO(se_tpg)->tpg_get_tag(se_tpg));
+
+       len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
+                       "alua_tg_pt_status=0x%02x\n",
+                       atomic_read(&port->sep_tg_pt_secondary_offline),
+                       port->sep_tg_pt_secondary_stat);
+
+       snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
+                       TPG_TFO(se_tpg)->get_fabric_name(), wwn,
+                       port->sep_lun->unpacked_lun);
+
+       return core_alua_write_tpg_metadata(path, md_buf, len);
+}
+
+static int core_alua_set_tg_pt_secondary_state(
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+       struct se_port *port,
+       int explict,
+       int offline)
+{
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       unsigned char *md_buf;
+       u32 md_buf_len;
+       int trans_delay_msecs;
+
+       spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+       if (!(tg_pt_gp)) {
+               spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+               printk(KERN_ERR "Unable to complete secondary state"
+                               " transition\n");
+               return -1;
+       }
+       trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
+       /*
+        * Set the secondary ALUA target port access state to OFFLINE
+        * or release the previously secondary state for struct se_port
+        */
+       if (offline)
+               atomic_set(&port->sep_tg_pt_secondary_offline, 1);
+       else
+               atomic_set(&port->sep_tg_pt_secondary_offline, 0);
+
+       md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
+       port->sep_tg_pt_secondary_stat = (explict) ?
+                       ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
+                       ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
+
+       printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
+               " to secondary access state: %s\n", (explict) ? "explict" :
+               "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
+               tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
+
+       spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       /*
+        * Do the optional transition delay after we set the secondary
+        * ALUA access state.
+        */
+       if (trans_delay_msecs != 0)
+               msleep_interruptible(trans_delay_msecs);
+       /*
+        * See if we need to update the ALUA fabric port metadata for
+        * secondary state and status
+        */
+       if (port->sep_tg_pt_secondary_write_md) {
+               md_buf = kzalloc(md_buf_len, GFP_KERNEL);
+               if (!(md_buf)) {
+                       printk(KERN_ERR "Unable to allocate md_buf for"
+                               " secondary ALUA access metadata\n");
+                       return -1;
+               }
+               mutex_lock(&port->sep_tg_pt_md_mutex);
+               core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
+                               md_buf, md_buf_len);
+               mutex_unlock(&port->sep_tg_pt_md_mutex);
+
+               kfree(md_buf);
+       }
+
+       return 0;
+}
+
+struct t10_alua_lu_gp *
+core_alua_allocate_lu_gp(const char *name, int def_group)
+{
+       struct t10_alua_lu_gp *lu_gp;
+
+       lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
+       if (!(lu_gp)) {
+               printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp\n");
+               return ERR_PTR(-ENOMEM);;
+       }
+       INIT_LIST_HEAD(&lu_gp->lu_gp_list);
+       INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
+       spin_lock_init(&lu_gp->lu_gp_lock);
+       atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
+
+       if (def_group) {
+               lu_gp->lu_gp_id = se_global->alua_lu_gps_counter++;;
+               lu_gp->lu_gp_valid_id = 1;
+               se_global->alua_lu_gps_count++;
+       }
+
+       return lu_gp;
+}
+
+int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
+{
+       struct t10_alua_lu_gp *lu_gp_tmp;
+       u16 lu_gp_id_tmp;
+       /*
+        * The lu_gp->lu_gp_id may only be set once..
+        */
+       if (lu_gp->lu_gp_valid_id) {
+               printk(KERN_WARNING "ALUA LU Group already has a valid ID,"
+                       " ignoring request\n");
+               return -1;
+       }
+
+       spin_lock(&se_global->lu_gps_lock);
+       if (se_global->alua_lu_gps_count == 0x0000ffff) {
+               printk(KERN_ERR "Maximum ALUA se_global->alua_lu_gps_count:"
+                               " 0x0000ffff reached\n");
+               spin_unlock(&se_global->lu_gps_lock);
+               kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
+               return -1;
+       }
+again:
+       lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
+                               se_global->alua_lu_gps_counter++;
+
+       list_for_each_entry(lu_gp_tmp, &se_global->g_lu_gps_list, lu_gp_list) {
+               if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
+                       if (!(lu_gp_id))
+                               goto again;
+
+                       printk(KERN_WARNING "ALUA Logical Unit Group ID: %hu"
+                               " already exists, ignoring request\n",
+                               lu_gp_id);
+                       spin_unlock(&se_global->lu_gps_lock);
+                       return -1;
+               }
+       }
+
+       lu_gp->lu_gp_id = lu_gp_id_tmp;
+       lu_gp->lu_gp_valid_id = 1;
+       list_add_tail(&lu_gp->lu_gp_list, &se_global->g_lu_gps_list);
+       se_global->alua_lu_gps_count++;
+       spin_unlock(&se_global->lu_gps_lock);
+
+       return 0;
+}
+
+static struct t10_alua_lu_gp_member *
+core_alua_allocate_lu_gp_mem(struct se_device *dev)
+{
+       struct t10_alua_lu_gp_member *lu_gp_mem;
+
+       lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
+       if (!(lu_gp_mem)) {
+               printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp_member\n");
+               return ERR_PTR(-ENOMEM);
+       }
+       INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
+       spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
+       atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
+
+       lu_gp_mem->lu_gp_mem_dev = dev;
+       dev->dev_alua_lu_gp_mem = lu_gp_mem;
+
+       return lu_gp_mem;
+}
+
+void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
+{
+       struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
+       /*
+        * Once we have reached this point, config_item_put() has
+        * already been called from target_core_alua_drop_lu_gp().
+        *
+        * Here, we remove the *lu_gp from the global list so that
+        * no associations can be made while we are releasing
+        * struct t10_alua_lu_gp.
+        */
+       spin_lock(&se_global->lu_gps_lock);
+       atomic_set(&lu_gp->lu_gp_shutdown, 1);
+       list_del(&lu_gp->lu_gp_list);
+       se_global->alua_lu_gps_count--;
+       spin_unlock(&se_global->lu_gps_lock);
+       /*
+        * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
+        * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
+        * released with core_alua_put_lu_gp_from_name()
+        */
+       while (atomic_read(&lu_gp->lu_gp_ref_cnt))
+               cpu_relax();
+       /*
+        * Release reference to struct t10_alua_lu_gp * from all associated
+        * struct se_device.
+        */
+       spin_lock(&lu_gp->lu_gp_lock);
+       list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
+                               &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
+               if (lu_gp_mem->lu_gp_assoc) {
+                       list_del(&lu_gp_mem->lu_gp_mem_list);
+                       lu_gp->lu_gp_members--;
+                       lu_gp_mem->lu_gp_assoc = 0;
+               }
+               spin_unlock(&lu_gp->lu_gp_lock);
+               /*
+                *
+                * lu_gp_mem is assoicated with a single
+                * struct se_device->dev_alua_lu_gp_mem, and is released when
+                * struct se_device is released via core_alua_free_lu_gp_mem().
+                *
+                * If the passed lu_gp does NOT match the default_lu_gp, assume
+                * we want to re-assocate a given lu_gp_mem with default_lu_gp.
+                */
+               spin_lock(&lu_gp_mem->lu_gp_mem_lock);
+               if (lu_gp != se_global->default_lu_gp)
+                       __core_alua_attach_lu_gp_mem(lu_gp_mem,
+                                       se_global->default_lu_gp);
+               else
+                       lu_gp_mem->lu_gp = NULL;
+               spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
+
+               spin_lock(&lu_gp->lu_gp_lock);
+       }
+       spin_unlock(&lu_gp->lu_gp_lock);
+
+       kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
+}
+
+void core_alua_free_lu_gp_mem(struct se_device *dev)
+{
+       struct se_subsystem_dev *su_dev = dev->se_sub_dev;
+       struct t10_alua *alua = T10_ALUA(su_dev);
+       struct t10_alua_lu_gp *lu_gp;
+       struct t10_alua_lu_gp_member *lu_gp_mem;
+
+       if (alua->alua_type != SPC3_ALUA_EMULATED)
+               return;
+
+       lu_gp_mem = dev->dev_alua_lu_gp_mem;
+       if (!(lu_gp_mem))
+               return;
+
+       while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
+               cpu_relax();
+
+       spin_lock(&lu_gp_mem->lu_gp_mem_lock);
+       lu_gp = lu_gp_mem->lu_gp;
+       if ((lu_gp)) {
+               spin_lock(&lu_gp->lu_gp_lock);
+               if (lu_gp_mem->lu_gp_assoc) {
+                       list_del(&lu_gp_mem->lu_gp_mem_list);
+                       lu_gp->lu_gp_members--;
+                       lu_gp_mem->lu_gp_assoc = 0;
+               }
+               spin_unlock(&lu_gp->lu_gp_lock);
+               lu_gp_mem->lu_gp = NULL;
+       }
+       spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
+
+       kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
+}
+
+struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
+{
+       struct t10_alua_lu_gp *lu_gp;
+       struct config_item *ci;
+
+       spin_lock(&se_global->lu_gps_lock);
+       list_for_each_entry(lu_gp, &se_global->g_lu_gps_list, lu_gp_list) {
+               if (!(lu_gp->lu_gp_valid_id))
+                       continue;
+               ci = &lu_gp->lu_gp_group.cg_item;
+               if (!(strcmp(config_item_name(ci), name))) {
+                       atomic_inc(&lu_gp->lu_gp_ref_cnt);
+                       spin_unlock(&se_global->lu_gps_lock);
+                       return lu_gp;
+               }
+       }
+       spin_unlock(&se_global->lu_gps_lock);
+
+       return NULL;
+}
+
+void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
+{
+       spin_lock(&se_global->lu_gps_lock);
+       atomic_dec(&lu_gp->lu_gp_ref_cnt);
+       spin_unlock(&se_global->lu_gps_lock);
+}
+
+/*
+ * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
+ */
+void __core_alua_attach_lu_gp_mem(
+       struct t10_alua_lu_gp_member *lu_gp_mem,
+       struct t10_alua_lu_gp *lu_gp)
+{
+       spin_lock(&lu_gp->lu_gp_lock);
+       lu_gp_mem->lu_gp = lu_gp;
+       lu_gp_mem->lu_gp_assoc = 1;
+       list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
+       lu_gp->lu_gp_members++;
+       spin_unlock(&lu_gp->lu_gp_lock);
+}
+
+/*
+ * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
+ */
+void __core_alua_drop_lu_gp_mem(
+       struct t10_alua_lu_gp_member *lu_gp_mem,
+       struct t10_alua_lu_gp *lu_gp)
+{
+       spin_lock(&lu_gp->lu_gp_lock);
+       list_del(&lu_gp_mem->lu_gp_mem_list);
+       lu_gp_mem->lu_gp = NULL;
+       lu_gp_mem->lu_gp_assoc = 0;
+       lu_gp->lu_gp_members--;
+       spin_unlock(&lu_gp->lu_gp_lock);
+}
+
+struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
+       struct se_subsystem_dev *su_dev,
+       const char *name,
+       int def_group)
+{
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+
+       tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
+       if (!(tg_pt_gp)) {
+               printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp\n");
+               return NULL;
+       }
+       INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
+       INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
+       mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
+       spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
+       atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
+       tg_pt_gp->tg_pt_gp_su_dev = su_dev;
+       tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
+       atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
+               ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
+       /*
+        * Enable both explict and implict ALUA support by default
+        */
+       tg_pt_gp->tg_pt_gp_alua_access_type =
+                       TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
+       /*
+        * Set the default Active/NonOptimized Delay in milliseconds
+        */
+       tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
+       tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
+
+       if (def_group) {
+               spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+               tg_pt_gp->tg_pt_gp_id =
+                               T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
+               tg_pt_gp->tg_pt_gp_valid_id = 1;
+               T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
+               list_add_tail(&tg_pt_gp->tg_pt_gp_list,
+                             &T10_ALUA(su_dev)->tg_pt_gps_list);
+               spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       }
+
+       return tg_pt_gp;
+}
+
+int core_alua_set_tg_pt_gp_id(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       u16 tg_pt_gp_id)
+{
+       struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+       struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
+       u16 tg_pt_gp_id_tmp;
+       /*
+        * The tg_pt_gp->tg_pt_gp_id may only be set once..
+        */
+       if (tg_pt_gp->tg_pt_gp_valid_id) {
+               printk(KERN_WARNING "ALUA TG PT Group already has a valid ID,"
+                       " ignoring request\n");
+               return -1;
+       }
+
+       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       if (T10_ALUA(su_dev)->alua_tg_pt_gps_count == 0x0000ffff) {
+               printk(KERN_ERR "Maximum ALUA alua_tg_pt_gps_count:"
+                       " 0x0000ffff reached\n");
+               spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+               kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
+               return -1;
+       }
+again:
+       tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
+                       T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
+
+       list_for_each_entry(tg_pt_gp_tmp, &T10_ALUA(su_dev)->tg_pt_gps_list,
+                       tg_pt_gp_list) {
+               if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
+                       if (!(tg_pt_gp_id))
+                               goto again;
+
+                       printk(KERN_ERR "ALUA Target Port Group ID: %hu already"
+                               " exists, ignoring request\n", tg_pt_gp_id);
+                       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                       return -1;
+               }
+       }
+
+       tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
+       tg_pt_gp->tg_pt_gp_valid_id = 1;
+       list_add_tail(&tg_pt_gp->tg_pt_gp_list,
+                       &T10_ALUA(su_dev)->tg_pt_gps_list);
+       T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
+       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+       return 0;
+}
+
+struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
+       struct se_port *port)
+{
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+
+       tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
+                               GFP_KERNEL);
+       if (!(tg_pt_gp_mem)) {
+               printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp_member\n");
+               return ERR_PTR(-ENOMEM);
+       }
+       INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+       spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
+
+       tg_pt_gp_mem->tg_pt = port;
+       port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
+       atomic_set(&port->sep_tg_pt_gp_active, 1);
+
+       return tg_pt_gp_mem;
+}
+
+void core_alua_free_tg_pt_gp(
+       struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+       struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
+       /*
+        * Once we have reached this point, config_item_put() has already
+        * been called from target_core_alua_drop_tg_pt_gp().
+        *
+        * Here we remove *tg_pt_gp from the global list so that
+        * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
+        * can be made while we are releasing struct t10_alua_tg_pt_gp.
+        */
+       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       list_del(&tg_pt_gp->tg_pt_gp_list);
+       T10_ALUA(su_dev)->alua_tg_pt_gps_counter--;
+       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       /*
+        * Allow a struct t10_alua_tg_pt_gp_member * referenced by
+        * core_alua_get_tg_pt_gp_by_name() in
+        * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
+        * to be released with core_alua_put_tg_pt_gp_from_name().
+        */
+       while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
+               cpu_relax();
+       /*
+        * Release reference to struct t10_alua_tg_pt_gp from all associated
+        * struct se_port.
+        */
+       spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+       list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
+                       &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
+               if (tg_pt_gp_mem->tg_pt_gp_assoc) {
+                       list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+                       tg_pt_gp->tg_pt_gp_members--;
+                       tg_pt_gp_mem->tg_pt_gp_assoc = 0;
+               }
+               spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+               /*
+                * tg_pt_gp_mem is assoicated with a single
+                * se_port->sep_alua_tg_pt_gp_mem, and is released via
+                * core_alua_free_tg_pt_gp_mem().
+                *
+                * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
+                * assume we want to re-assocate a given tg_pt_gp_mem with
+                * default_tg_pt_gp.
+                */
+               spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+               if (tg_pt_gp != T10_ALUA(su_dev)->default_tg_pt_gp) {
+                       __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
+                                       T10_ALUA(su_dev)->default_tg_pt_gp);
+               } else
+                       tg_pt_gp_mem->tg_pt_gp = NULL;
+               spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+               spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+       }
+       spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+
+       kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
+}
+
+void core_alua_free_tg_pt_gp_mem(struct se_port *port)
+{
+       struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
+       struct t10_alua *alua = T10_ALUA(su_dev);
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+
+       if (alua->alua_type != SPC3_ALUA_EMULATED)
+               return;
+
+       tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+       if (!(tg_pt_gp_mem))
+               return;
+
+       while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
+               cpu_relax();
+
+       spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+       if ((tg_pt_gp)) {
+               spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+               if (tg_pt_gp_mem->tg_pt_gp_assoc) {
+                       list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+                       tg_pt_gp->tg_pt_gp_members--;
+                       tg_pt_gp_mem->tg_pt_gp_assoc = 0;
+               }
+               spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+               tg_pt_gp_mem->tg_pt_gp = NULL;
+       }
+       spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+       kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
+}
+
+static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
+       struct se_subsystem_dev *su_dev,
+       const char *name)
+{
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       struct config_item *ci;
+
+       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
+                       tg_pt_gp_list) {
+               if (!(tg_pt_gp->tg_pt_gp_valid_id))
+                       continue;
+               ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
+               if (!(strcmp(config_item_name(ci), name))) {
+                       atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
+                       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+                       return tg_pt_gp;
+               }
+       }
+       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+
+       return NULL;
+}
+
+static void core_alua_put_tg_pt_gp_from_name(
+       struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+       struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
+
+       spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+       atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
+       spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
+}
+
+/*
+ * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
+ */
+void __core_alua_attach_tg_pt_gp_mem(
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+       struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+       spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+       tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
+       tg_pt_gp_mem->tg_pt_gp_assoc = 1;
+       list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
+                       &tg_pt_gp->tg_pt_gp_mem_list);
+       tg_pt_gp->tg_pt_gp_members++;
+       spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+}
+
+/*
+ * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
+ */
+static void __core_alua_drop_tg_pt_gp_mem(
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
+       struct t10_alua_tg_pt_gp *tg_pt_gp)
+{
+       spin_lock(&tg_pt_gp->tg_pt_gp_lock);
+       list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
+       tg_pt_gp_mem->tg_pt_gp = NULL;
+       tg_pt_gp_mem->tg_pt_gp_assoc = 0;
+       tg_pt_gp->tg_pt_gp_members--;
+       spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
+}
+
+ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
+{
+       struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
+       struct config_item *tg_pt_ci;
+       struct t10_alua *alua = T10_ALUA(su_dev);
+       struct t10_alua_tg_pt_gp *tg_pt_gp;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+       ssize_t len = 0;
+
+       if (alua->alua_type != SPC3_ALUA_EMULATED)
+               return len;
+
+       tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+       if (!(tg_pt_gp_mem))
+               return len;
+
+       spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+       if ((tg_pt_gp)) {
+               tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
+               len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
+                       " %hu\nTG Port Primary Access State: %s\nTG Port "
+                       "Primary Access Status: %s\nTG Port Secondary Access"
+                       " State: %s\nTG Port Secondary Access Status: %s\n",
+                       config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
+                       core_alua_dump_state(atomic_read(
+                                       &tg_pt_gp->tg_pt_gp_alua_access_state)),
+                       core_alua_dump_status(
+                               tg_pt_gp->tg_pt_gp_alua_access_status),
+                       (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
+                       "Offline" : "None",
+                       core_alua_dump_status(port->sep_tg_pt_secondary_stat));
+       }
+       spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+       return len;
+}
+
+ssize_t core_alua_store_tg_pt_gp_info(
+       struct se_port *port,
+       const char *page,
+       size_t count)
+{
+       struct se_portal_group *tpg;
+       struct se_lun *lun;
+       struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
+       struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+       unsigned char buf[TG_PT_GROUP_NAME_BUF];
+       int move = 0;
+
+       tpg = port->sep_tpg;
+       lun = port->sep_lun;
+
+       if (T10_ALUA(su_dev)->alua_type != SPC3_ALUA_EMULATED) {
+               printk(KERN_WARNING "SPC3_ALUA_EMULATED not enabled for"
+                       " %s/tpgt_%hu/%s\n", TPG_TFO(tpg)->tpg_get_wwn(tpg),
+                       TPG_TFO(tpg)->tpg_get_tag(tpg),
+                       config_item_name(&lun->lun_group.cg_item));
+               return -EINVAL;
+       }
+
+       if (count > TG_PT_GROUP_NAME_BUF) {
+               printk(KERN_ERR "ALUA Target Port Group alias too large!\n");
+               return -EINVAL;
+       }
+       memset(buf, 0, TG_PT_GROUP_NAME_BUF);
+       memcpy(buf, page, count);
+       /*
+        * Any ALUA target port group alias besides "NULL" means we will be
+        * making a new group association.
+        */
+       if (strcmp(strstrip(buf), "NULL")) {
+               /*
+                * core_alua_get_tg_pt_gp_by_name() will increment reference to
+                * struct t10_alua_tg_pt_gp.  This reference is released with
+                * core_alua_put_tg_pt_gp_from_name() below.
+                */
+               tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
+                                       strstrip(buf));
+               if (!(tg_pt_gp_new))
+                       return -ENODEV;
+       }
+       tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
+       if (!(tg_pt_gp_mem)) {
+               if (tg_pt_gp_new)
+                       core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
+               printk(KERN_ERR "NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
+               return -EINVAL;
+       }
+
+       spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
+       if ((tg_pt_gp)) {
+               /*
+                * Clearing an existing tg_pt_gp association, and replacing
+                * with the default_tg_pt_gp.
+                */
+               if (!(tg_pt_gp_new)) {
+                       printk(KERN_INFO "Target_Core_ConfigFS: Moving"
+                               " %s/tpgt_%hu/%s from ALUA Target Port Group:"
+                               " alua/%s, ID: %hu back to"
+                               " default_tg_pt_gp\n",
+                               TPG_TFO(tpg)->tpg_get_wwn(tpg),
+                               TPG_TFO(tpg)->tpg_get_tag(tpg),
+                               config_item_name(&lun->lun_group.cg_item),
+                               config_item_name(
+                                       &tg_pt_gp->tg_pt_gp_group.cg_item),
+                               tg_pt_gp->tg_pt_gp_id);
+
+                       __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
+                       __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
+                                       T10_ALUA(su_dev)->default_tg_pt_gp);
+                       spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+
+                       return count;
+               }
+               /*
+                * Removing existing association of tg_pt_gp_mem with tg_pt_gp
+                */
+               __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
+               move = 1;
+       }
+       /*
+        * Associate tg_pt_gp_mem with tg_pt_gp_new.
+        */
+       __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
+       spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
+       printk(KERN_INFO "Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
+               " Target Port Group: alua/%s, ID: %hu\n", (move) ?
+               "Moving" : "Adding", TPG_TFO(tpg)->tpg_get_wwn(tpg),
+               TPG_TFO(tpg)->tpg_get_tag(tpg),
+               config_item_name(&lun->lun_group.cg_item),
+               config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
+               tg_pt_gp_new->tg_pt_gp_id);
+
+       core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
+       return count;
+}
+
+ssize_t core_alua_show_access_type(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       char *page)
+{
+       if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
+           (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
+               return sprintf(page, "Implict and Explict\n");
+       else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
+               return sprintf(page, "Implict\n");
+       else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
+               return sprintf(page, "Explict\n");
+       else
+               return sprintf(page, "None\n");
+}
+
+ssize_t core_alua_store_access_type(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       const char *page,
+       size_t count)
+{
+       unsigned long tmp;
+       int ret;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract alua_access_type\n");
+               return -EINVAL;
+       }
+       if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
+               printk(KERN_ERR "Illegal value for alua_access_type:"
+                               " %lu\n", tmp);
+               return -EINVAL;
+       }
+       if (tmp == 3)
+               tg_pt_gp->tg_pt_gp_alua_access_type =
+                       TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
+       else if (tmp == 2)
+               tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
+       else if (tmp == 1)
+               tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
+       else
+               tg_pt_gp->tg_pt_gp_alua_access_type = 0;
+
+       return count;
+}
+
+ssize_t core_alua_show_nonop_delay_msecs(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       char *page)
+{
+       return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
+}
+
+ssize_t core_alua_store_nonop_delay_msecs(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       const char *page,
+       size_t count)
+{
+       unsigned long tmp;
+       int ret;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract nonop_delay_msecs\n");
+               return -EINVAL;
+       }
+       if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
+               printk(KERN_ERR "Passed nonop_delay_msecs: %lu, exceeds"
+                       " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
+                       ALUA_MAX_NONOP_DELAY_MSECS);
+               return -EINVAL;
+       }
+       tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
+
+       return count;
+}
+
+ssize_t core_alua_show_trans_delay_msecs(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       char *page)
+{
+       return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
+}
+
+ssize_t core_alua_store_trans_delay_msecs(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       const char *page,
+       size_t count)
+{
+       unsigned long tmp;
+       int ret;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract trans_delay_msecs\n");
+               return -EINVAL;
+       }
+       if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
+               printk(KERN_ERR "Passed trans_delay_msecs: %lu, exceeds"
+                       " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
+                       ALUA_MAX_TRANS_DELAY_MSECS);
+               return -EINVAL;
+       }
+       tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
+
+       return count;
+}
+
+ssize_t core_alua_show_preferred_bit(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       char *page)
+{
+       return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
+}
+
+ssize_t core_alua_store_preferred_bit(
+       struct t10_alua_tg_pt_gp *tg_pt_gp,
+       const char *page,
+       size_t count)
+{
+       unsigned long tmp;
+       int ret;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract preferred ALUA value\n");
+               return -EINVAL;
+       }
+       if ((tmp != 0) && (tmp != 1)) {
+               printk(KERN_ERR "Illegal value for preferred ALUA: %lu\n", tmp);
+               return -EINVAL;
+       }
+       tg_pt_gp->tg_pt_gp_pref = (int)tmp;
+
+       return count;
+}
+
+ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
+{
+       if (!(lun->lun_sep))
+               return -ENODEV;
+
+       return sprintf(page, "%d\n",
+               atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
+}
+
+ssize_t core_alua_store_offline_bit(
+       struct se_lun *lun,
+       const char *page,
+       size_t count)
+{
+       struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
+       unsigned long tmp;
+       int ret;
+
+       if (!(lun->lun_sep))
+               return -ENODEV;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract alua_tg_pt_offline value\n");
+               return -EINVAL;
+       }
+       if ((tmp != 0) && (tmp != 1)) {
+               printk(KERN_ERR "Illegal value for alua_tg_pt_offline: %lu\n",
+                               tmp);
+               return -EINVAL;
+       }
+       tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
+       if (!(tg_pt_gp_mem)) {
+               printk(KERN_ERR "Unable to locate *tg_pt_gp_mem\n");
+               return -EINVAL;
+       }
+
+       ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
+                       lun->lun_sep, 0, (int)tmp);
+       if (ret < 0)
+               return -EINVAL;
+
+       return count;
+}
+
+ssize_t core_alua_show_secondary_status(
+       struct se_lun *lun,
+       char *page)
+{
+       return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
+}
+
+ssize_t core_alua_store_secondary_status(
+       struct se_lun *lun,
+       const char *page,
+       size_t count)
+{
+       unsigned long tmp;
+       int ret;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract alua_tg_pt_status\n");
+               return -EINVAL;
+       }
+       if ((tmp != ALUA_STATUS_NONE) &&
+           (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
+           (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
+               printk(KERN_ERR "Illegal value for alua_tg_pt_status: %lu\n",
+                               tmp);
+               return -EINVAL;
+       }
+       lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
+
+       return count;
+}
+
+ssize_t core_alua_show_secondary_write_metadata(
+       struct se_lun *lun,
+       char *page)
+{
+       return sprintf(page, "%d\n",
+                       lun->lun_sep->sep_tg_pt_secondary_write_md);
+}
+
+ssize_t core_alua_store_secondary_write_metadata(
+       struct se_lun *lun,
+       const char *page,
+       size_t count)
+{
+       unsigned long tmp;
+       int ret;
+
+       ret = strict_strtoul(page, 0, &tmp);
+       if (ret < 0) {
+               printk(KERN_ERR "Unable to extract alua_tg_pt_write_md\n");
+               return -EINVAL;
+       }
+       if ((tmp != 0) && (tmp != 1)) {
+               printk(KERN_ERR "Illegal value for alua_tg_pt_write_md:"
+                               " %lu\n", tmp);
+               return -EINVAL;
+       }
+       lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
+
+       return count;
+}
+
+int core_setup_alua(struct se_device *dev, int force_pt)
+{
+       struct se_subsystem_dev *su_dev = dev->se_sub_dev;
+       struct t10_alua *alua = T10_ALUA(su_dev);
+       struct t10_alua_lu_gp_member *lu_gp_mem;
+       /*
+        * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
+        * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
+        * cause a problem because libata and some SATA RAID HBAs appear
+        * under Linux/SCSI, but emulate SCSI logic themselves.
+        */
+       if (((TRANSPORT(dev)->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
+           !(DEV_ATTRIB(dev)->emulate_alua)) || force_pt) {
+               alua->alua_type = SPC_ALUA_PASSTHROUGH;
+               alua->alua_state_check = &core_alua_state_check_nop;
+               printk(KERN_INFO "%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
+                       " emulation\n", TRANSPORT(dev)->name);
+               return 0;
+       }
+       /*
+        * If SPC-3 or above is reported by real or emulated struct se_device,
+        * use emulated ALUA.
+        */
+       if (TRANSPORT(dev)->get_device_rev(dev) >= SCSI_3) {
+               printk(KERN_INFO "%s: Enabling ALUA Emulation for SPC-3"
+                       " device\n", TRANSPORT(dev)->name);
+               /*
+                * Assoicate this struct se_device with the default ALUA
+                * LUN Group.
+                */
+               lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
+               if (IS_ERR(lu_gp_mem) || !lu_gp_mem)
+                       return -1;
+
+               alua->alua_type = SPC3_ALUA_EMULATED;
+               alua->alua_state_check = &core_alua_state_check;
+               spin_lock(&lu_gp_mem->lu_gp_mem_lock);
+               __core_alua_attach_lu_gp_mem(lu_gp_mem,
+                               se_global->default_lu_gp);
+               spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
+
+               printk(KERN_INFO "%s: Adding to default ALUA LU Group:"
+                       " core/alua/lu_gps/default_lu_gp\n",
+                       TRANSPORT(dev)->name);
+       } else {
+               alua->alua_type = SPC2_ALUA_DISABLED;
+               alua->alua_state_check = &core_alua_state_check_nop;
+               printk(KERN_INFO "%s: Disabling ALUA Emulation for SPC-2"
+                       " device\n", TRANSPORT(dev)->name);
+       }
+
+       return 0;
+}