/******************************************************************************* * Filename: target_core_ua.c * * This file contains logic for SPC-3 Unit Attention emulation * * 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/slab.h> #include <linux/spinlock.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> #include <target/target_core_base.h> #include <target/target_core_fabric.h> #include <target/target_core_configfs.h> #include "target_core_internal.h" #include "target_core_alua.h" #include "target_core_pr.h" #include "target_core_ua.h" int core_scsi3_ua_check( struct se_cmd *cmd, unsigned char *cdb) { struct se_dev_entry *deve; struct se_session *sess = cmd->se_sess; struct se_node_acl *nacl; if (!sess) return 0; nacl = sess->se_node_acl; if (!nacl) return 0; deve = nacl->device_list[cmd->orig_fe_lun]; if (!atomic_read(&deve->ua_count)) return 0; /* * From sam4r14, section 5.14 Unit attention condition: * * a) if an INQUIRY command enters the enabled command state, the * device server shall process the INQUIRY command and shall neither * report nor clear any unit attention condition; * b) if a REPORT LUNS command enters the enabled command state, the * device server shall process the REPORT LUNS command and shall not * report any unit attention condition; * e) if a REQUEST SENSE command enters the enabled command state while * a unit attention condition exists for the SCSI initiator port * associated with the I_T nexus on which the REQUEST SENSE command * was received, then the device server shall process the command * and either: */ switch (cdb[0]) { case INQUIRY: case REPORT_LUNS: case REQUEST_SENSE: return 0; default: return -EINVAL; } return -EINVAL; } int core_scsi3_ua_allocate( struct se_node_acl *nacl, u32 unpacked_lun, u8 asc, u8 ascq) { struct se_dev_entry *deve; struct se_ua *ua, *ua_p, *ua_tmp; /* * PASSTHROUGH OPS */ if (!nacl) return -EINVAL; ua = kmem_cache_zalloc(se_ua_cache, GFP_ATOMIC); if (!ua) { pr_err("Unable to allocate struct se_ua\n"); return -ENOMEM; } INIT_LIST_HEAD(&ua->ua_dev_list); INIT_LIST_HEAD(&ua->ua_nacl_list); ua->ua_nacl = nacl; ua->ua_asc = asc; ua->ua_ascq = ascq; spin_lock_irq(&nacl->device_list_lock); deve = nacl->device_list[unpacked_lun]; spin_lock(&deve->ua_lock); list_for_each_entry_safe(ua_p, ua_tmp, &deve->ua_list, ua_nacl_list) { /* * Do not report the same UNIT ATTENTION twice.. */ if ((ua_p->ua_asc == asc) && (ua_p->ua_ascq == ascq)) { spin_unlock(&deve->ua_lock); spin_unlock_irq(&nacl->device_list_lock); kmem_cache_free(se_ua_cache, ua); return 0; } /* * Attach the highest priority Unit Attention to * the head of the list following sam4r14, * Section 5.14 Unit Attention Condition: * * POWER ON, RESET, OR BUS DEVICE RESET OCCURRED highest * POWER ON OCCURRED or * DEVICE INTERNAL RESET * SCSI BUS RESET OCCURRED or * MICROCODE HAS BEEN CHANGED or * protocol specific * BUS DEVICE RESET FUNCTION OCCURRED * I_T NEXUS LOSS OCCURRED * COMMANDS CLEARED BY POWER LOSS NOTIFICATION * all others Lowest * * Each of the ASCQ codes listed above are defined in * the 29h ASC family, see spc4r17 Table D.1 */ if (ua_p->ua_asc == 0x29) { if ((asc == 0x29) && (ascq > ua_p->ua_ascq)) list_add(&ua->ua_nacl_list, &deve->ua_list); else list_add_tail(&ua->ua_nacl_list, &deve->ua_list); } else if (ua_p->ua_asc == 0x2a) { /* * Incoming Family 29h ASCQ codes will override * Family 2AHh ASCQ codes for Unit Attention condition. */ if ((asc == 0x29) || (ascq > ua_p->ua_asc)) list_add(&ua->ua_nacl_list, &deve->ua_list); else list_add_tail(&ua->ua_nacl_list, &deve->ua_list); } else list_add_tail(&ua->ua_nacl_list, &deve->ua_list); spin_unlock(&deve->ua_lock); spin_unlock_irq(&nacl->device_list_lock); atomic_inc(&deve->ua_count); smp_mb__after_atomic_inc(); return 0; } list_add_tail(&ua->ua_nacl_list, &deve->ua_list); spin_unlock(&deve->ua_lock); spin_unlock_irq(&nacl->device_list_lock); pr_debug("[%s]: Allocated UNIT ATTENTION, mapped LUN: %u, ASC:" " 0x%02x, ASCQ: 0x%02x\n", nacl->se_tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun, asc, ascq); atomic_inc(&deve->ua_count); smp_mb__after_atomic_inc(); return 0; } void core_scsi3_ua_release_all( struct se_dev_entry *deve) { struct se_ua *ua, *ua_p; spin_lock(&deve->ua_lock); list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) { list_del(&ua->ua_nacl_list); kmem_cache_free(se_ua_cache, ua); atomic_dec(&deve->ua_count); smp_mb__after_atomic_dec(); } spin_unlock(&deve->ua_lock); } void core_scsi3_ua_for_check_condition( struct se_cmd *cmd, u8 *asc, u8 *ascq) { struct se_device *dev = cmd->se_dev; struct se_dev_entry *deve; struct se_session *sess = cmd->se_sess; struct se_node_acl *nacl; struct se_ua *ua = NULL, *ua_p; int head = 1; if (!sess) return; nacl = sess->se_node_acl; if (!nacl) return; spin_lock_irq(&nacl->device_list_lock); deve = nacl->device_list[cmd->orig_fe_lun]; if (!atomic_read(&deve->ua_count)) { spin_unlock_irq(&nacl->device_list_lock); return; } /* * The highest priority Unit Attentions are placed at the head of the * struct se_dev_entry->ua_list, and will be returned in CHECK_CONDITION + * sense data for the received CDB. */ spin_lock(&deve->ua_lock); list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) { /* * For ua_intlck_ctrl code not equal to 00b, only report the * highest priority UNIT_ATTENTION and ASC/ASCQ without * clearing it. */ if (dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl != 0) { *asc = ua->ua_asc; *ascq = ua->ua_ascq; break; } /* * Otherwise for the default 00b, release the UNIT ATTENTION * condition. Return the ASC/ASCQ of the highest priority UA * (head of the list) in the outgoing CHECK_CONDITION + sense. */ if (head) { *asc = ua->ua_asc; *ascq = ua->ua_ascq; head = 0; } list_del(&ua->ua_nacl_list); kmem_cache_free(se_ua_cache, ua); atomic_dec(&deve->ua_count); smp_mb__after_atomic_dec(); } spin_unlock(&deve->ua_lock); spin_unlock_irq(&nacl->device_list_lock); pr_debug("[%s]: %s UNIT ATTENTION condition with" " INTLCK_CTRL: %d, mapped LUN: %u, got CDB: 0x%02x" " reported ASC: 0x%02x, ASCQ: 0x%02x\n", nacl->se_tpg->se_tpg_tfo->get_fabric_name(), (dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl != 0) ? "Reporting" : "Releasing", dev->se_sub_dev->se_dev_attrib.emulate_ua_intlck_ctrl, cmd->orig_fe_lun, cmd->t_task_cdb[0], *asc, *ascq); } int core_scsi3_ua_clear_for_request_sense( struct se_cmd *cmd, u8 *asc, u8 *ascq) { struct se_dev_entry *deve; struct se_session *sess = cmd->se_sess; struct se_node_acl *nacl; struct se_ua *ua = NULL, *ua_p; int head = 1; if (!sess) return -EINVAL; nacl = sess->se_node_acl; if (!nacl) return -EINVAL; spin_lock_irq(&nacl->device_list_lock); deve = nacl->device_list[cmd->orig_fe_lun]; if (!atomic_read(&deve->ua_count)) { spin_unlock_irq(&nacl->device_list_lock); return -EPERM; } /* * The highest priority Unit Attentions are placed at the head of the * struct se_dev_entry->ua_list. The First (and hence highest priority) * ASC/ASCQ will be returned in REQUEST_SENSE payload data for the * matching struct se_lun. * * Once the returning ASC/ASCQ values are set, we go ahead and * release all of the Unit Attention conditions for the associated * struct se_lun. */ spin_lock(&deve->ua_lock); list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) { if (head) { *asc = ua->ua_asc; *ascq = ua->ua_ascq; head = 0; } list_del(&ua->ua_nacl_list); kmem_cache_free(se_ua_cache, ua); atomic_dec(&deve->ua_count); smp_mb__after_atomic_dec(); } spin_unlock(&deve->ua_lock); spin_unlock_irq(&nacl->device_list_lock); pr_debug("[%s]: Released UNIT ATTENTION condition, mapped" " LUN: %u, got REQUEST_SENSE reported ASC: 0x%02x," " ASCQ: 0x%02x\n", nacl->se_tpg->se_tpg_tfo->get_fabric_name(), cmd->orig_fe_lun, *asc, *ascq); return (head) ? -EPERM : 0; }