/******************************************************************************* * 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 * * 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 #include #include #include #include #include #include #include #include #include #include #include "target_core_internal.h" #include "target_core_alua.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); static u16 alua_lu_gps_counter; static u32 alua_lu_gps_count; static DEFINE_SPINLOCK(lu_gps_lock); static LIST_HEAD(lu_gps_list); struct t10_alua_lu_gp *default_lu_gp; /* * REPORT_TARGET_PORT_GROUPS * * See spc4r17 section 6.27 */ int target_emulate_report_target_port_groups(struct se_cmd *cmd) { struct se_subsystem_dev *su_dev = cmd->se_dev->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; u32 rd_len = 0, off; int ext_hdr = (cmd->t_task_cdb[1] & 0x20); /* * Skip over RESERVED area to first Target port group descriptor * depending on the PARAMETER DATA FORMAT type.. */ if (ext_hdr != 0) off = 8; else off = 4; if (cmd->data_length < off) { pr_warn("REPORT TARGET PORT GROUPS allocation length %u too" " small for %s header\n", cmd->data_length, (ext_hdr) ? "extended" : "normal"); cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD; return -EINVAL; } buf = transport_kmap_data_sg(cmd); spin_lock(&su_dev->t10_alua.tg_pt_gps_lock); list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list, tg_pt_gp_list) { /* * Check if the Target port group and Target port descriptor list * based on tg_pt_gp_members count will fit into the response payload. * Otherwise, bump rd_len to let the initiator know we have exceeded * the allocation length and the response is truncated. */ if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) > cmd->data_length) { rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4); continue; } /* * 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(&su_dev->t10_alua.tg_pt_gps_lock); /* * Set the RETURN DATA LENGTH set in the header of the DataIN Payload */ put_unaligned_be32(rd_len, &buf[0]); /* * Fill in the Extended header parameter data format if requested */ if (ext_hdr != 0) { buf[4] = 0x10; /* * Set the implict transition time (in seconds) for the application * client to use as a base for it's transition timeout value. * * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN * this CDB was received upon to determine this value individually * for ALUA target port group. */ port = cmd->se_lun->lun_sep; tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem; if (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; if (tg_pt_gp) buf[5] = tg_pt_gp->tg_pt_gp_implict_trans_secs; spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock); } } transport_kunmap_data_sg(cmd); target_complete_cmd(cmd, GOOD); return 0; } /* * SET_TARGET_PORT_GROUPS for explict ALUA operation. * * See spc4r17 section 6.35 */ int target_emulate_set_target_port_groups(struct se_cmd *cmd) { struct se_device *dev = cmd->se_dev; struct se_subsystem_dev *su_dev = dev->se_sub_dev; struct se_port *port, *l_port = cmd->se_lun->lun_sep; struct se_node_acl *nacl = cmd->se_sess->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 *ptr; u32 len = 4; /* Skip over RESERVED area in header */ int alua_access_state, primary = 0, rc; u16 tg_pt_id, rtpi; if (!l_port) { cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; return -EINVAL; } if (cmd->data_length < 4) { pr_warn("SET TARGET PORT GROUPS parameter list length %u too" " small\n", cmd->data_length); cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST; return -EINVAL; } buf = transport_kmap_data_sg(cmd); /* * 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) { pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n"); cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE; rc = -EINVAL; goto out; } 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); pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n"); cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE; rc = -EINVAL; goto out; } 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) { pr_debug("Unable to process SET_TARGET_PORT_GROUPS" " while TPGS_EXPLICT_ALUA is disabled\n"); cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE; rc = -EINVAL; goto out; } ptr = &buf[4]; /* Skip over RESERVED area in header */ 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. */ cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST; rc = -EINVAL; goto out; } 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 = get_unaligned_be16(ptr + 2); /* * Locate the matching target port group ID from * the global tg_pt_gp list */ spin_lock(&su_dev->t10_alua.tg_pt_gps_lock); list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.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(&su_dev->t10_alua.tg_pt_gps_lock); rc = core_alua_do_port_transition(tg_pt_gp, dev, l_port, nacl, alua_access_state, 1); spin_lock(&su_dev->t10_alua.tg_pt_gps_lock); atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt); smp_mb__after_atomic_dec(); break; } spin_unlock(&su_dev->t10_alua.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) { cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST; rc = -EINVAL; goto out; } } else { /* * Extact the RELATIVE TARGET PORT IDENTIFIER to identify * the Target Port in question for the the incoming * SET_TARGET_PORT_GROUPS op. */ rtpi = get_unaligned_be16(ptr + 2); /* * 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) { cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST; rc = -EINVAL; goto out; } } ptr += 4; len += 4; } out: transport_kunmap_data_sg(cmd); if (!rc) target_complete_cmd(cmd, GOOD); return rc; } 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] & 0x1f) { 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] & 0x1f) { 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] & 0x1f) { 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 = cmd->se_lun; 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; pr_debug("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 separate conditional * statement so the compiler knows explicitly 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: pr_err("Unknown ALUA access state: 0x%02x\n", out_alua_state); return -EINVAL; } 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: pr_err("Unknown ALUA access state: 0x%02x\n", state); return -EINVAL; } 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) { pr_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) { pr_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); pr_debug("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) { pr_err("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(&su_dev->t10_alua.tg_pt_gps_lock); list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.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(&su_dev->t10_alua.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(&su_dev->t10_alua.tg_pt_gps_lock); atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt); smp_mb__after_atomic_dec(); } spin_unlock(&su_dev->t10_alua.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); pr_debug("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", se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg)); if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu", se_tpg->se_tpg_tfo->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", se_tpg->se_tpg_tfo->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); pr_err("Unable to complete secondary state" " transition\n"); return -EINVAL; } 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; pr_debug("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) { pr_err("Unable to allocate md_buf for" " secondary ALUA access metadata\n"); return -ENOMEM; } 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) { pr_err("Unable to allocate struct t10_alua_lu_gp\n"); return ERR_PTR(-ENOMEM); } INIT_LIST_HEAD(&lu_gp->lu_gp_node); 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 = alua_lu_gps_counter++; lu_gp->lu_gp_valid_id = 1; 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) { pr_warn("ALUA LU Group already has a valid ID," " ignoring request\n"); return -EINVAL; } spin_lock(&lu_gps_lock); if (alua_lu_gps_count == 0x0000ffff) { pr_err("Maximum ALUA alua_lu_gps_count:" " 0x0000ffff reached\n"); spin_unlock(&lu_gps_lock); kmem_cache_free(t10_alua_lu_gp_cache, lu_gp); return -ENOSPC; } again: lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id : alua_lu_gps_counter++; list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) { if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) { if (!lu_gp_id) goto again; pr_warn("ALUA Logical Unit Group ID: %hu" " already exists, ignoring request\n", lu_gp_id); spin_unlock(&lu_gps_lock); return -EINVAL; } } lu_gp->lu_gp_id = lu_gp_id_tmp; lu_gp->lu_gp_valid_id = 1; list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list); alua_lu_gps_count++; spin_unlock(&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) { pr_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(&lu_gps_lock); list_del(&lu_gp->lu_gp_node); alua_lu_gps_count--; spin_unlock(&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 associated 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 != default_lu_gp) __core_alua_attach_lu_gp_mem(lu_gp_mem, 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 = &su_dev->t10_alua; 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(&lu_gps_lock); list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) { 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(&lu_gps_lock); return lu_gp; } } spin_unlock(&lu_gps_lock); return NULL; } void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp) { spin_lock(&lu_gps_lock); atomic_dec(&lu_gp->lu_gp_ref_cnt); spin_unlock(&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) { pr_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; tg_pt_gp->tg_pt_gp_implict_trans_secs = ALUA_DEFAULT_IMPLICT_TRANS_SECS; if (def_group) { spin_lock(&su_dev->t10_alua.tg_pt_gps_lock); tg_pt_gp->tg_pt_gp_id = su_dev->t10_alua.alua_tg_pt_gps_counter++; tg_pt_gp->tg_pt_gp_valid_id = 1; su_dev->t10_alua.alua_tg_pt_gps_count++; list_add_tail(&tg_pt_gp->tg_pt_gp_list, &su_dev->t10_alua.tg_pt_gps_list); spin_unlock(&su_dev->t10_alua.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) { pr_warn("ALUA TG PT Group already has a valid ID," " ignoring request\n"); return -EINVAL; } spin_lock(&su_dev->t10_alua.tg_pt_gps_lock); if (su_dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) { pr_err("Maximum ALUA alua_tg_pt_gps_count:" " 0x0000ffff reached\n"); spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock); kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp); return -ENOSPC; } again: tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id : su_dev->t10_alua.alua_tg_pt_gps_counter++; list_for_each_entry(tg_pt_gp_tmp, &su_dev->t10_alua.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; pr_err("ALUA Target Port Group ID: %hu already" " exists, ignoring request\n", tg_pt_gp_id); spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock); return -EINVAL; } } 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, &su_dev->t10_alua.tg_pt_gps_list); su_dev->t10_alua.alua_tg_pt_gps_count++; spin_unlock(&su_dev->t10_alua.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) { pr_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; 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(&su_dev->t10_alua.tg_pt_gps_lock); list_del(&tg_pt_gp->tg_pt_gp_list); su_dev->t10_alua.alua_tg_pt_gps_counter--; spin_unlock(&su_dev->t10_alua.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 associated 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 != su_dev->t10_alua.default_tg_pt_gp) { __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, su_dev->t10_alua.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 = &su_dev->t10_alua; 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(&su_dev->t10_alua.tg_pt_gps_lock); list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.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(&su_dev->t10_alua.tg_pt_gps_lock); return tg_pt_gp; } } spin_unlock(&su_dev->t10_alua.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(&su_dev->t10_alua.tg_pt_gps_lock); atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt); spin_unlock(&su_dev->t10_alua.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 = &su_dev->t10_alua; 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 (su_dev->t10_alua.alua_type != SPC3_ALUA_EMULATED) { pr_warn("SPC3_ALUA_EMULATED not enabled for" " %s/tpgt_%hu/%s\n", tpg->se_tpg_tfo->tpg_get_wwn(tpg), tpg->se_tpg_tfo->tpg_get_tag(tpg), config_item_name(&lun->lun_group.cg_item)); return -EINVAL; } if (count > TG_PT_GROUP_NAME_BUF) { pr_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); pr_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) { pr_debug("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->se_tpg_tfo->tpg_get_wwn(tpg), tpg->se_tpg_tfo->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, su_dev->t10_alua.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); pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA" " Target Port Group: alua/%s, ID: %hu\n", (move) ? "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg), tpg->se_tpg_tfo->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) { pr_err("Unable to extract alua_access_type\n"); return -EINVAL; } if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) { pr_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) { pr_err("Unable to extract nonop_delay_msecs\n"); return -EINVAL; } if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) { pr_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) { pr_err("Unable to extract trans_delay_msecs\n"); return -EINVAL; } if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) { pr_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_implict_trans_secs( struct t10_alua_tg_pt_gp *tg_pt_gp, char *page) { return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implict_trans_secs); } ssize_t core_alua_store_implict_trans_secs( 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) { pr_err("Unable to extract implict_trans_secs\n"); return -EINVAL; } if (tmp > ALUA_MAX_IMPLICT_TRANS_SECS) { pr_err("Passed implict_trans_secs: %lu, exceeds" " ALUA_MAX_IMPLICT_TRANS_SECS: %d\n", tmp, ALUA_MAX_IMPLICT_TRANS_SECS); return -EINVAL; } tg_pt_gp->tg_pt_gp_implict_trans_secs = (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) { pr_err("Unable to extract preferred ALUA value\n"); return -EINVAL; } if ((tmp != 0) && (tmp != 1)) { pr_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) { pr_err("Unable to extract alua_tg_pt_offline value\n"); return -EINVAL; } if ((tmp != 0) && (tmp != 1)) { pr_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) { pr_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) { pr_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)) { pr_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) { pr_err("Unable to extract alua_tg_pt_write_md\n"); return -EINVAL; } if ((tmp != 0) && (tmp != 1)) { pr_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 = &su_dev->t10_alua; 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 (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) && !(dev->se_sub_dev->se_dev_attrib.emulate_alua)) || force_pt) { alua->alua_type = SPC_ALUA_PASSTHROUGH; alua->alua_state_check = &core_alua_state_check_nop; pr_debug("%s: Using SPC_ALUA_PASSTHROUGH, no ALUA" " emulation\n", dev->transport->name); return 0; } /* * If SPC-3 or above is reported by real or emulated struct se_device, * use emulated ALUA. */ if (dev->transport->get_device_rev(dev) >= SCSI_3) { pr_debug("%s: Enabling ALUA Emulation for SPC-3" " device\n", dev->transport->name); /* * Associate 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)) return PTR_ERR(lu_gp_mem); 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, default_lu_gp); spin_unlock(&lu_gp_mem->lu_gp_mem_lock); pr_debug("%s: Adding to default ALUA LU Group:" " core/alua/lu_gps/default_lu_gp\n", dev->transport->name); } else { alua->alua_type = SPC2_ALUA_DISABLED; alua->alua_state_check = &core_alua_state_check_nop; pr_debug("%s: Disabling ALUA Emulation for SPC-2" " device\n", dev->transport->name); } return 0; }