1 /******************************************************************************* 2 * Filename: target_core_ua.c 3 * 4 * This file contains logic for SPC-3 Unit Attention emulation 5 * 6 * Copyright (c) 2009,2010 Rising Tide Systems 7 * Copyright (c) 2009,2010 Linux-iSCSI.org 8 * 9 * Nicholas A. Bellinger <nab@kernel.org> 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2 of the License, or 14 * (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 24 * 25 ******************************************************************************/ 26 27 #include <linux/version.h> 28 #include <linux/slab.h> 29 #include <linux/spinlock.h> 30 #include <scsi/scsi.h> 31 #include <scsi/scsi_cmnd.h> 32 33 #include <target/target_core_base.h> 34 #include <target/target_core_device.h> 35 #include <target/target_core_transport.h> 36 #include <target/target_core_fabric_ops.h> 37 #include <target/target_core_configfs.h> 38 39 #include "target_core_alua.h" 40 #include "target_core_hba.h" 41 #include "target_core_pr.h" 42 #include "target_core_ua.h" 43 44 int core_scsi3_ua_check( 45 struct se_cmd *cmd, 46 unsigned char *cdb) 47 { 48 struct se_dev_entry *deve; 49 struct se_session *sess = cmd->se_sess; 50 struct se_node_acl *nacl; 51 52 if (!(sess)) 53 return 0; 54 55 nacl = sess->se_node_acl; 56 if (!(nacl)) 57 return 0; 58 59 deve = &nacl->device_list[cmd->orig_fe_lun]; 60 if (!(atomic_read(&deve->ua_count))) 61 return 0; 62 /* 63 * From sam4r14, section 5.14 Unit attention condition: 64 * 65 * a) if an INQUIRY command enters the enabled command state, the 66 * device server shall process the INQUIRY command and shall neither 67 * report nor clear any unit attention condition; 68 * b) if a REPORT LUNS command enters the enabled command state, the 69 * device server shall process the REPORT LUNS command and shall not 70 * report any unit attention condition; 71 * e) if a REQUEST SENSE command enters the enabled command state while 72 * a unit attention condition exists for the SCSI initiator port 73 * associated with the I_T nexus on which the REQUEST SENSE command 74 * was received, then the device server shall process the command 75 * and either: 76 */ 77 switch (cdb[0]) { 78 case INQUIRY: 79 case REPORT_LUNS: 80 case REQUEST_SENSE: 81 return 0; 82 default: 83 return -1; 84 } 85 86 return -1; 87 } 88 89 int core_scsi3_ua_allocate( 90 struct se_node_acl *nacl, 91 u32 unpacked_lun, 92 u8 asc, 93 u8 ascq) 94 { 95 struct se_dev_entry *deve; 96 struct se_ua *ua, *ua_p, *ua_tmp; 97 /* 98 * PASSTHROUGH OPS 99 */ 100 if (!(nacl)) 101 return -1; 102 103 ua = kmem_cache_zalloc(se_ua_cache, GFP_ATOMIC); 104 if (!(ua)) { 105 printk(KERN_ERR "Unable to allocate struct se_ua\n"); 106 return -1; 107 } 108 INIT_LIST_HEAD(&ua->ua_dev_list); 109 INIT_LIST_HEAD(&ua->ua_nacl_list); 110 111 ua->ua_nacl = nacl; 112 ua->ua_asc = asc; 113 ua->ua_ascq = ascq; 114 115 spin_lock_irq(&nacl->device_list_lock); 116 deve = &nacl->device_list[unpacked_lun]; 117 118 spin_lock(&deve->ua_lock); 119 list_for_each_entry_safe(ua_p, ua_tmp, &deve->ua_list, ua_nacl_list) { 120 /* 121 * Do not report the same UNIT ATTENTION twice.. 122 */ 123 if ((ua_p->ua_asc == asc) && (ua_p->ua_ascq == ascq)) { 124 spin_unlock(&deve->ua_lock); 125 spin_unlock_irq(&nacl->device_list_lock); 126 kmem_cache_free(se_ua_cache, ua); 127 return 0; 128 } 129 /* 130 * Attach the highest priority Unit Attention to 131 * the head of the list following sam4r14, 132 * Section 5.14 Unit Attention Condition: 133 * 134 * POWER ON, RESET, OR BUS DEVICE RESET OCCURRED highest 135 * POWER ON OCCURRED or 136 * DEVICE INTERNAL RESET 137 * SCSI BUS RESET OCCURRED or 138 * MICROCODE HAS BEEN CHANGED or 139 * protocol specific 140 * BUS DEVICE RESET FUNCTION OCCURRED 141 * I_T NEXUS LOSS OCCURRED 142 * COMMANDS CLEARED BY POWER LOSS NOTIFICATION 143 * all others Lowest 144 * 145 * Each of the ASCQ codes listed above are defined in 146 * the 29h ASC family, see spc4r17 Table D.1 147 */ 148 if (ua_p->ua_asc == 0x29) { 149 if ((asc == 0x29) && (ascq > ua_p->ua_ascq)) 150 list_add(&ua->ua_nacl_list, 151 &deve->ua_list); 152 else 153 list_add_tail(&ua->ua_nacl_list, 154 &deve->ua_list); 155 } else if (ua_p->ua_asc == 0x2a) { 156 /* 157 * Incoming Family 29h ASCQ codes will override 158 * Family 2AHh ASCQ codes for Unit Attention condition. 159 */ 160 if ((asc == 0x29) || (ascq > ua_p->ua_asc)) 161 list_add(&ua->ua_nacl_list, 162 &deve->ua_list); 163 else 164 list_add_tail(&ua->ua_nacl_list, 165 &deve->ua_list); 166 } else 167 list_add_tail(&ua->ua_nacl_list, 168 &deve->ua_list); 169 spin_unlock(&deve->ua_lock); 170 spin_unlock_irq(&nacl->device_list_lock); 171 172 atomic_inc(&deve->ua_count); 173 smp_mb__after_atomic_inc(); 174 return 0; 175 } 176 list_add_tail(&ua->ua_nacl_list, &deve->ua_list); 177 spin_unlock(&deve->ua_lock); 178 spin_unlock_irq(&nacl->device_list_lock); 179 180 printk(KERN_INFO "[%s]: Allocated UNIT ATTENTION, mapped LUN: %u, ASC:" 181 " 0x%02x, ASCQ: 0x%02x\n", 182 TPG_TFO(nacl->se_tpg)->get_fabric_name(), unpacked_lun, 183 asc, ascq); 184 185 atomic_inc(&deve->ua_count); 186 smp_mb__after_atomic_inc(); 187 return 0; 188 } 189 190 void core_scsi3_ua_release_all( 191 struct se_dev_entry *deve) 192 { 193 struct se_ua *ua, *ua_p; 194 195 spin_lock(&deve->ua_lock); 196 list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) { 197 list_del(&ua->ua_nacl_list); 198 kmem_cache_free(se_ua_cache, ua); 199 200 atomic_dec(&deve->ua_count); 201 smp_mb__after_atomic_dec(); 202 } 203 spin_unlock(&deve->ua_lock); 204 } 205 206 void core_scsi3_ua_for_check_condition( 207 struct se_cmd *cmd, 208 u8 *asc, 209 u8 *ascq) 210 { 211 struct se_device *dev = SE_DEV(cmd); 212 struct se_dev_entry *deve; 213 struct se_session *sess = cmd->se_sess; 214 struct se_node_acl *nacl; 215 struct se_ua *ua = NULL, *ua_p; 216 int head = 1; 217 218 if (!(sess)) 219 return; 220 221 nacl = sess->se_node_acl; 222 if (!(nacl)) 223 return; 224 225 spin_lock_irq(&nacl->device_list_lock); 226 deve = &nacl->device_list[cmd->orig_fe_lun]; 227 if (!(atomic_read(&deve->ua_count))) { 228 spin_unlock_irq(&nacl->device_list_lock); 229 return; 230 } 231 /* 232 * The highest priority Unit Attentions are placed at the head of the 233 * struct se_dev_entry->ua_list, and will be returned in CHECK_CONDITION + 234 * sense data for the received CDB. 235 */ 236 spin_lock(&deve->ua_lock); 237 list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) { 238 /* 239 * For ua_intlck_ctrl code not equal to 00b, only report the 240 * highest priority UNIT_ATTENTION and ASC/ASCQ without 241 * clearing it. 242 */ 243 if (DEV_ATTRIB(dev)->emulate_ua_intlck_ctrl != 0) { 244 *asc = ua->ua_asc; 245 *ascq = ua->ua_ascq; 246 break; 247 } 248 /* 249 * Otherwise for the default 00b, release the UNIT ATTENTION 250 * condition. Return the ASC/ASCQ of the higest priority UA 251 * (head of the list) in the outgoing CHECK_CONDITION + sense. 252 */ 253 if (head) { 254 *asc = ua->ua_asc; 255 *ascq = ua->ua_ascq; 256 head = 0; 257 } 258 list_del(&ua->ua_nacl_list); 259 kmem_cache_free(se_ua_cache, ua); 260 261 atomic_dec(&deve->ua_count); 262 smp_mb__after_atomic_dec(); 263 } 264 spin_unlock(&deve->ua_lock); 265 spin_unlock_irq(&nacl->device_list_lock); 266 267 printk(KERN_INFO "[%s]: %s UNIT ATTENTION condition with" 268 " INTLCK_CTRL: %d, mapped LUN: %u, got CDB: 0x%02x" 269 " reported ASC: 0x%02x, ASCQ: 0x%02x\n", 270 TPG_TFO(nacl->se_tpg)->get_fabric_name(), 271 (DEV_ATTRIB(dev)->emulate_ua_intlck_ctrl != 0) ? "Reporting" : 272 "Releasing", DEV_ATTRIB(dev)->emulate_ua_intlck_ctrl, 273 cmd->orig_fe_lun, T_TASK(cmd)->t_task_cdb[0], *asc, *ascq); 274 } 275 276 int core_scsi3_ua_clear_for_request_sense( 277 struct se_cmd *cmd, 278 u8 *asc, 279 u8 *ascq) 280 { 281 struct se_dev_entry *deve; 282 struct se_session *sess = cmd->se_sess; 283 struct se_node_acl *nacl; 284 struct se_ua *ua = NULL, *ua_p; 285 int head = 1; 286 287 if (!(sess)) 288 return -1; 289 290 nacl = sess->se_node_acl; 291 if (!(nacl)) 292 return -1; 293 294 spin_lock_irq(&nacl->device_list_lock); 295 deve = &nacl->device_list[cmd->orig_fe_lun]; 296 if (!(atomic_read(&deve->ua_count))) { 297 spin_unlock_irq(&nacl->device_list_lock); 298 return -1; 299 } 300 /* 301 * The highest priority Unit Attentions are placed at the head of the 302 * struct se_dev_entry->ua_list. The First (and hence highest priority) 303 * ASC/ASCQ will be returned in REQUEST_SENSE payload data for the 304 * matching struct se_lun. 305 * 306 * Once the returning ASC/ASCQ values are set, we go ahead and 307 * release all of the Unit Attention conditions for the assoicated 308 * struct se_lun. 309 */ 310 spin_lock(&deve->ua_lock); 311 list_for_each_entry_safe(ua, ua_p, &deve->ua_list, ua_nacl_list) { 312 if (head) { 313 *asc = ua->ua_asc; 314 *ascq = ua->ua_ascq; 315 head = 0; 316 } 317 list_del(&ua->ua_nacl_list); 318 kmem_cache_free(se_ua_cache, ua); 319 320 atomic_dec(&deve->ua_count); 321 smp_mb__after_atomic_dec(); 322 } 323 spin_unlock(&deve->ua_lock); 324 spin_unlock_irq(&nacl->device_list_lock); 325 326 printk(KERN_INFO "[%s]: Released UNIT ATTENTION condition, mapped" 327 " LUN: %u, got REQUEST_SENSE reported ASC: 0x%02x," 328 " ASCQ: 0x%02x\n", TPG_TFO(nacl->se_tpg)->get_fabric_name(), 329 cmd->orig_fe_lun, *asc, *ascq); 330 331 return (head) ? -1 : 0; 332 } 333