drivers/target/target_core_alua.c

   1 /*******************************************************************************
   2  * Filename:  target_core_alua.c
   3  *
   4  * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
   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 <linux/configfs.h>
  31 #include <scsi/scsi.h>
  32 #include <scsi/scsi_cmnd.h>
  33
  34 #include <target/target_core_base.h>
  35 #include <target/target_core_device.h>
  36 #include <target/target_core_transport.h>
  37 #include <target/target_core_fabric_ops.h>
  38 #include <target/target_core_configfs.h>
  39
  40 #include "target_core_alua.h"
  41 #include "target_core_hba.h"
  42 #include "target_core_ua.h"
  43
  44 static int core_alua_check_transition(int state, int *primary);
  45 static int core_alua_set_tg_pt_secondary_state(
  46                 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
  47                 struct se_port *port, int explict, int offline);
  48
  49 static u16 alua_lu_gps_counter;
  50 static u32 alua_lu_gps_count;
  51
  52 static DEFINE_SPINLOCK(lu_gps_lock);
  53 static LIST_HEAD(lu_gps_list);
  54
  55 struct t10_alua_lu_gp *default_lu_gp;
  56
  57 /*
  58  * REPORT_TARGET_PORT_GROUPS
  59  *
  60  * See spc4r17 section 6.27
  61  */
  62 int core_emulate_report_target_port_groups(struct se_cmd *cmd)
  63 {
  64         struct se_subsystem_dev *su_dev = cmd->se_lun->lun_se_dev->se_sub_dev;
  65         struct se_port *port;
  66         struct t10_alua_tg_pt_gp *tg_pt_gp;
  67         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
  68         unsigned char *buf = (unsigned char *)cmd->t_task->t_task_buf;
  69         u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
  70                                     Target port group descriptor */
  71
  72         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
  73         list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
  74                         tg_pt_gp_list) {
  75                 /*
  76                  * PREF: Preferred target port bit, determine if this
  77                  * bit should be set for port group.
  78                  */
  79                 if (tg_pt_gp->tg_pt_gp_pref)
  80                         buf[off] = 0x80;
  81                 /*
  82                  * Set the ASYMMETRIC ACCESS State
  83                  */
  84                 buf[off++] |= (atomic_read(
  85                         &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
  86                 /*
  87                  * Set supported ASYMMETRIC ACCESS State bits
  88                  */
  89                 buf[off] = 0x80; /* T_SUP */
  90                 buf[off] |= 0x40; /* O_SUP */
  91                 buf[off] |= 0x8; /* U_SUP */
  92                 buf[off] |= 0x4; /* S_SUP */
  93                 buf[off] |= 0x2; /* AN_SUP */
  94                 buf[off++] |= 0x1; /* AO_SUP */
  95                 /*
  96                  * TARGET PORT GROUP
  97                  */
  98                 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
  99                 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
 100
 101                 off++; /* Skip over Reserved */
 102                 /*
 103                  * STATUS CODE
 104                  */
 105                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 106                 /*
 107                  * Vendor Specific field
 108                  */
 109                 buf[off++] = 0x00;
 110                 /*
 111                  * TARGET PORT COUNT
 112                  */
 113                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 114                 rd_len += 8;
 115
 116                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 117                 list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
 118                                 tg_pt_gp_mem_list) {
 119                         port = tg_pt_gp_mem->tg_pt;
 120                         /*
 121                          * Start Target Port descriptor format
 122                          *
 123                          * See spc4r17 section 6.2.7 Table 247
 124                          */
 125                         off += 2; /* Skip over Obsolete */
 126                         /*
 127                          * Set RELATIVE TARGET PORT IDENTIFIER
 128                          */
 129                         buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
 130                         buf[off++] = (port->sep_rtpi & 0xff);
 131                         rd_len += 4;
 132                 }
 133                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 134         }
 135         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 136         /*
 137          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 138          */
 139         buf[0] = ((rd_len >> 24) & 0xff);
 140         buf[1] = ((rd_len >> 16) & 0xff);
 141         buf[2] = ((rd_len >> 8) & 0xff);
 142         buf[3] = (rd_len & 0xff);
 143
 144         return 0;
 145 }
 146
 147 /*
 148  * SET_TARGET_PORT_GROUPS for explict ALUA operation.
 149  *
 150  * See spc4r17 section 6.35
 151  */
 152 int core_emulate_set_target_port_groups(struct se_cmd *cmd)
 153 {
 154         struct se_device *dev = cmd->se_lun->lun_se_dev;
 155         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
 156         struct se_port *port, *l_port = cmd->se_lun->lun_sep;
 157         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 158         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 159         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
 160         unsigned char *buf = (unsigned char *)cmd->t_task->t_task_buf;
 161         unsigned char *ptr = &buf[4]; /* Skip over RESERVED area in header */
 162         u32 len = 4; /* Skip over RESERVED area in header */
 163         int alua_access_state, primary = 0, rc;
 164         u16 tg_pt_id, rtpi;
 165
 166         if (!(l_port))
 167                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 168         /*
 169          * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
 170          * for the local tg_pt_gp.
 171          */
 172         l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
 173         if (!(l_tg_pt_gp_mem)) {
 174                 printk(KERN_ERR "Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
 175                 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 176         }
 177         spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 178         l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
 179         if (!(l_tg_pt_gp)) {
 180                 spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 181                 printk(KERN_ERR "Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
 182                 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 183         }
 184         rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
 185         spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 186
 187         if (!(rc)) {
 188                 printk(KERN_INFO "Unable to process SET_TARGET_PORT_GROUPS"
 189                                 " while TPGS_EXPLICT_ALUA is disabled\n");
 190                 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 191         }
 192
 193         while (len < cmd->data_length) {
 194                 alua_access_state = (ptr[0] & 0x0f);
 195                 /*
 196                  * Check the received ALUA access state, and determine if
 197                  * the state is a primary or secondary target port asymmetric
 198                  * access state.
 199                  */
 200                 rc = core_alua_check_transition(alua_access_state, &primary);
 201                 if (rc != 0) {
 202                         /*
 203                          * If the SET TARGET PORT GROUPS attempts to establish
 204                          * an invalid combination of target port asymmetric
 205                          * access states or attempts to establish an
 206                          * unsupported target port asymmetric access state,
 207                          * then the command shall be terminated with CHECK
 208                          * CONDITION status, with the sense key set to ILLEGAL
 209                          * REQUEST, and the additional sense code set to INVALID
 210                          * FIELD IN PARAMETER LIST.
 211                          */
 212                         return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 213                 }
 214                 rc = -1;
 215                 /*
 216                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 217                  * specifies a primary target port asymmetric access state,
 218                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 219                  * a primary target port group for which the primary target
 220                  * port asymmetric access state shall be changed. If the
 221                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 222                  * port asymmetric access state, then the TARGET PORT GROUP OR
 223                  * TARGET PORT field specifies the relative target port
 224                  * identifier (see 3.1.120) of the target port for which the
 225                  * secondary target port asymmetric access state shall be
 226                  * changed.
 227                  */
 228                 if (primary) {
 229                         tg_pt_id = ((ptr[2] << 8) & 0xff);
 230                         tg_pt_id |= (ptr[3] & 0xff);
 231                         /*
 232                          * Locate the matching target port group ID from
 233                          * the global tg_pt_gp list
 234                          */
 235                         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 236                         list_for_each_entry(tg_pt_gp,
 237                                         &su_dev->t10_alua.tg_pt_gps_list,
 238                                         tg_pt_gp_list) {
 239                                 if (!(tg_pt_gp->tg_pt_gp_valid_id))
 240                                         continue;
 241
 242                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 243                                         continue;
 244
 245                                 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 246                                 smp_mb__after_atomic_inc();
 247                                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 248
 249                                 rc = core_alua_do_port_transition(tg_pt_gp,
 250                                                 dev, l_port, nacl,
 251                                                 alua_access_state, 1);
 252
 253                                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 254                                 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 255                                 smp_mb__after_atomic_dec();
 256                                 break;
 257                         }
 258                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 259                         /*
 260                          * If not matching target port group ID can be located
 261                          * throw an exception with ASCQ: INVALID_PARAMETER_LIST
 262                          */
 263                         if (rc != 0)
 264                                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 265                 } else {
 266                         /*
 267                          * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
 268                          * the Target Port in question for the the incoming
 269                          * SET_TARGET_PORT_GROUPS op.
 270                          */
 271                         rtpi = ((ptr[2] << 8) & 0xff);
 272                         rtpi |= (ptr[3] & 0xff);
 273                         /*
 274                          * Locate the matching relative target port identifer
 275                          * for the struct se_device storage object.
 276                          */
 277                         spin_lock(&dev->se_port_lock);
 278                         list_for_each_entry(port, &dev->dev_sep_list,
 279                                                         sep_list) {
 280                                 if (port->sep_rtpi != rtpi)
 281                                         continue;
 282
 283                                 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 284                                 spin_unlock(&dev->se_port_lock);
 285
 286                                 rc = core_alua_set_tg_pt_secondary_state(
 287                                                 tg_pt_gp_mem, port, 1, 1);
 288
 289                                 spin_lock(&dev->se_port_lock);
 290                                 break;
 291                         }
 292                         spin_unlock(&dev->se_port_lock);
 293                         /*
 294                          * If not matching relative target port identifier can
 295                          * be located, throw an exception with ASCQ:
 296                          * INVALID_PARAMETER_LIST
 297                          */
 298                         if (rc != 0)
 299                                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 300                 }
 301
 302                 ptr += 4;
 303                 len += 4;
 304         }
 305
 306         return 0;
 307 }
 308
 309 static inline int core_alua_state_nonoptimized(
 310         struct se_cmd *cmd,
 311         unsigned char *cdb,
 312         int nonop_delay_msecs,
 313         u8 *alua_ascq)
 314 {
 315         /*
 316          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 317          * later to determine if processing of this cmd needs to be
 318          * temporarily delayed for the Active/NonOptimized primary access state.
 319          */
 320         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 321         cmd->alua_nonop_delay = nonop_delay_msecs;
 322         return 0;
 323 }
 324
 325 static inline int core_alua_state_standby(
 326         struct se_cmd *cmd,
 327         unsigned char *cdb,
 328         u8 *alua_ascq)
 329 {
 330         /*
 331          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 332          * spc4r17 section 5.9.2.4.4
 333          */
 334         switch (cdb[0]) {
 335         case INQUIRY:
 336         case LOG_SELECT:
 337         case LOG_SENSE:
 338         case MODE_SELECT:
 339         case MODE_SENSE:
 340         case REPORT_LUNS:
 341         case RECEIVE_DIAGNOSTIC:
 342         case SEND_DIAGNOSTIC:
 343         case MAINTENANCE_IN:
 344                 switch (cdb[1]) {
 345                 case MI_REPORT_TARGET_PGS:
 346                         return 0;
 347                 default:
 348                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 349                         return 1;
 350                 }
 351         case MAINTENANCE_OUT:
 352                 switch (cdb[1]) {
 353                 case MO_SET_TARGET_PGS:
 354                         return 0;
 355                 default:
 356                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 357                         return 1;
 358                 }
 359         case REQUEST_SENSE:
 360         case PERSISTENT_RESERVE_IN:
 361         case PERSISTENT_RESERVE_OUT:
 362         case READ_BUFFER:
 363         case WRITE_BUFFER:
 364                 return 0;
 365         default:
 366                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 367                 return 1;
 368         }
 369
 370         return 0;
 371 }
 372
 373 static inline int core_alua_state_unavailable(
 374         struct se_cmd *cmd,
 375         unsigned char *cdb,
 376         u8 *alua_ascq)
 377 {
 378         /*
 379          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 380          * spc4r17 section 5.9.2.4.5
 381          */
 382         switch (cdb[0]) {
 383         case INQUIRY:
 384         case REPORT_LUNS:
 385         case MAINTENANCE_IN:
 386                 switch (cdb[1]) {
 387                 case MI_REPORT_TARGET_PGS:
 388                         return 0;
 389                 default:
 390                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 391                         return 1;
 392                 }
 393         case MAINTENANCE_OUT:
 394                 switch (cdb[1]) {
 395                 case MO_SET_TARGET_PGS:
 396                         return 0;
 397                 default:
 398                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 399                         return 1;
 400                 }
 401         case REQUEST_SENSE:
 402         case READ_BUFFER:
 403         case WRITE_BUFFER:
 404                 return 0;
 405         default:
 406                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 407                 return 1;
 408         }
 409
 410         return 0;
 411 }
 412
 413 static inline int core_alua_state_transition(
 414         struct se_cmd *cmd,
 415         unsigned char *cdb,
 416         u8 *alua_ascq)
 417 {
 418         /*
 419          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
 420          * spc4r17 section 5.9.2.5
 421          */
 422         switch (cdb[0]) {
 423         case INQUIRY:
 424         case REPORT_LUNS:
 425         case MAINTENANCE_IN:
 426                 switch (cdb[1]) {
 427                 case MI_REPORT_TARGET_PGS:
 428                         return 0;
 429                 default:
 430                         *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 431                         return 1;
 432                 }
 433         case REQUEST_SENSE:
 434         case READ_BUFFER:
 435         case WRITE_BUFFER:
 436                 return 0;
 437         default:
 438                 *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 439                 return 1;
 440         }
 441
 442         return 0;
 443 }
 444
 445 /*
 446  * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
 447  * in transport_cmd_sequencer().  This function is assigned to
 448  * struct t10_alua *->state_check() in core_setup_alua()
 449  */
 450 static int core_alua_state_check_nop(
 451         struct se_cmd *cmd,
 452         unsigned char *cdb,
 453         u8 *alua_ascq)
 454 {
 455         return 0;
 456 }
 457
 458 /*
 459  * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
 460  * This function is assigned to struct t10_alua *->state_check() in
 461  * core_setup_alua()
 462  *
 463  * Also, this function can return three different return codes to
 464  * signal transport_generic_cmd_sequencer()
 465  *
 466  * return 1: Is used to signal LUN not accecsable, and check condition/not ready
 467  * return 0: Used to signal success
 468  * reutrn -1: Used to signal failure, and invalid cdb field
 469  */
 470 static int core_alua_state_check(
 471         struct se_cmd *cmd,
 472         unsigned char *cdb,
 473         u8 *alua_ascq)
 474 {
 475         struct se_lun *lun = cmd->se_lun;
 476         struct se_port *port = lun->lun_sep;
 477         struct t10_alua_tg_pt_gp *tg_pt_gp;
 478         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
 479         int out_alua_state, nonop_delay_msecs;
 480
 481         if (!(port))
 482                 return 0;
 483         /*
 484          * First, check for a struct se_port specific secondary ALUA target port
 485          * access state: OFFLINE
 486          */
 487         if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
 488                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 489                 printk(KERN_INFO "ALUA: Got secondary offline status for local"
 490                                 " target port\n");
 491                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 492                 return 1;
 493         }
 494          /*
 495          * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
 496          * ALUA target port group, to obtain current ALUA access state.
 497          * Otherwise look for the underlying struct se_device association with
 498          * a ALUA logical unit group.
 499          */
 500         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 501         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 502         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
 503         out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 504         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 505         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 506         /*
 507          * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a separate conditional
 508          * statement so the compiler knows explicitly to check this case first.
 509          * For the Optimized ALUA access state case, we want to process the
 510          * incoming fabric cmd ASAP..
 511          */
 512         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
 513                 return 0;
 514
 515         switch (out_alua_state) {
 516         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 517                 return core_alua_state_nonoptimized(cmd, cdb,
 518                                         nonop_delay_msecs, alua_ascq);
 519         case ALUA_ACCESS_STATE_STANDBY:
 520                 return core_alua_state_standby(cmd, cdb, alua_ascq);
 521         case ALUA_ACCESS_STATE_UNAVAILABLE:
 522                 return core_alua_state_unavailable(cmd, cdb, alua_ascq);
 523         case ALUA_ACCESS_STATE_TRANSITION:
 524                 return core_alua_state_transition(cmd, cdb, alua_ascq);
 525         /*
 526          * OFFLINE is a secondary ALUA target port group access state, that is
 527          * handled above with struct se_port->sep_tg_pt_secondary_offline=1
 528          */
 529         case ALUA_ACCESS_STATE_OFFLINE:
 530         default:
 531                 printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n",
 532                                 out_alua_state);
 533                 return -EINVAL;
 534         }
 535
 536         return 0;
 537 }
 538
 539 /*
 540  * Check implict and explict ALUA state change request.
 541  */
 542 static int core_alua_check_transition(int state, int *primary)
 543 {
 544         switch (state) {
 545         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 546         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 547         case ALUA_ACCESS_STATE_STANDBY:
 548         case ALUA_ACCESS_STATE_UNAVAILABLE:
 549                 /*
 550                  * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 551                  * defined as primary target port asymmetric access states.
 552                  */
 553                 *primary = 1;
 554                 break;
 555         case ALUA_ACCESS_STATE_OFFLINE:
 556                 /*
 557                  * OFFLINE state is defined as a secondary target port
 558                  * asymmetric access state.
 559                  */
 560                 *primary = 0;
 561                 break;
 562         default:
 563                 printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n", state);
 564                 return -EINVAL;
 565         }
 566
 567         return 0;
 568 }
 569
 570 static char *core_alua_dump_state(int state)
 571 {
 572         switch (state) {
 573         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 574                 return "Active/Optimized";
 575         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 576                 return "Active/NonOptimized";
 577         case ALUA_ACCESS_STATE_STANDBY:
 578                 return "Standby";
 579         case ALUA_ACCESS_STATE_UNAVAILABLE:
 580                 return "Unavailable";
 581         case ALUA_ACCESS_STATE_OFFLINE:
 582                 return "Offline";
 583         default:
 584                 return "Unknown";
 585         }
 586
 587         return NULL;
 588 }
 589
 590 char *core_alua_dump_status(int status)
 591 {
 592         switch (status) {
 593         case ALUA_STATUS_NONE:
 594                 return "None";
 595         case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
 596                 return "Altered by Explict STPG";
 597         case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
 598                 return "Altered by Implict ALUA";
 599         default:
 600                 return "Unknown";
 601         }
 602
 603         return NULL;
 604 }
 605
 606 /*
 607  * Used by fabric modules to determine when we need to delay processing
 608  * for the Active/NonOptimized paths..
 609  */
 610 int core_alua_check_nonop_delay(
 611         struct se_cmd *cmd)
 612 {
 613         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 614                 return 0;
 615         if (in_interrupt())
 616                 return 0;
 617         /*
 618          * The ALUA Active/NonOptimized access state delay can be disabled
 619          * in via configfs with a value of zero
 620          */
 621         if (!(cmd->alua_nonop_delay))
 622                 return 0;
 623         /*
 624          * struct se_cmd->alua_nonop_delay gets set by a target port group
 625          * defined interval in core_alua_state_nonoptimized()
 626          */
 627         msleep_interruptible(cmd->alua_nonop_delay);
 628         return 0;
 629 }
 630 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 631
 632 /*
 633  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
 634  *
 635  */
 636 static int core_alua_write_tpg_metadata(
 637         const char *path,
 638         unsigned char *md_buf,
 639         u32 md_buf_len)
 640 {
 641         mm_segment_t old_fs;
 642         struct file *file;
 643         struct iovec iov[1];
 644         int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
 645
 646         memset(iov, 0, sizeof(struct iovec));
 647
 648         file = filp_open(path, flags, 0600);
 649         if (IS_ERR(file) || !file || !file->f_dentry) {
 650                 printk(KERN_ERR "filp_open(%s) for ALUA metadata failed\n",
 651                         path);
 652                 return -ENODEV;
 653         }
 654
 655         iov[0].iov_base = &md_buf[0];
 656         iov[0].iov_len = md_buf_len;
 657
 658         old_fs = get_fs();
 659         set_fs(get_ds());
 660         ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
 661         set_fs(old_fs);
 662
 663         if (ret < 0) {
 664                 printk(KERN_ERR "Error writing ALUA metadata file: %s\n", path);
 665                 filp_close(file, NULL);
 666                 return -EIO;
 667         }
 668         filp_close(file, NULL);
 669
 670         return 0;
 671 }
 672
 673 /*
 674  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
 675  */
 676 static int core_alua_update_tpg_primary_metadata(
 677         struct t10_alua_tg_pt_gp *tg_pt_gp,
 678         int primary_state,
 679         unsigned char *md_buf)
 680 {
 681         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
 682         struct t10_wwn *wwn = &su_dev->t10_wwn;
 683         char path[ALUA_METADATA_PATH_LEN];
 684         int len;
 685
 686         memset(path, 0, ALUA_METADATA_PATH_LEN);
 687
 688         len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
 689                         "tg_pt_gp_id=%hu\n"
 690                         "alua_access_state=0x%02x\n"
 691                         "alua_access_status=0x%02x\n",
 692                         tg_pt_gp->tg_pt_gp_id, primary_state,
 693                         tg_pt_gp->tg_pt_gp_alua_access_status);
 694
 695         snprintf(path, ALUA_METADATA_PATH_LEN,
 696                 "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
 697                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 698
 699         return core_alua_write_tpg_metadata(path, md_buf, len);
 700 }
 701
 702 static int core_alua_do_transition_tg_pt(
 703         struct t10_alua_tg_pt_gp *tg_pt_gp,
 704         struct se_port *l_port,
 705         struct se_node_acl *nacl,
 706         unsigned char *md_buf,
 707         int new_state,
 708         int explict)
 709 {
 710         struct se_dev_entry *se_deve;
 711         struct se_lun_acl *lacl;
 712         struct se_port *port;
 713         struct t10_alua_tg_pt_gp_member *mem;
 714         int old_state = 0;
 715         /*
 716          * Save the old primary ALUA access state, and set the current state
 717          * to ALUA_ACCESS_STATE_TRANSITION.
 718          */
 719         old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 720         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
 721                         ALUA_ACCESS_STATE_TRANSITION);
 722         tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
 723                                 ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
 724                                 ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
 725         /*
 726          * Check for the optional ALUA primary state transition delay
 727          */
 728         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
 729                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
 730
 731         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 732         list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
 733                                 tg_pt_gp_mem_list) {
 734                 port = mem->tg_pt;
 735                 /*
 736                  * After an implicit target port asymmetric access state
 737                  * change, a device server shall establish a unit attention
 738                  * condition for the initiator port associated with every I_T
 739                  * nexus with the additional sense code set to ASYMMETRIC
 740                  * ACCESS STATE CHAGED.
 741                  *
 742                  * After an explicit target port asymmetric access state
 743                  * change, a device server shall establish a unit attention
 744                  * condition with the additional sense code set to ASYMMETRIC
 745                  * ACCESS STATE CHANGED for the initiator port associated with
 746                  * every I_T nexus other than the I_T nexus on which the SET
 747                  * TARGET PORT GROUPS command
 748                  */
 749                 atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
 750                 smp_mb__after_atomic_inc();
 751                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 752
 753                 spin_lock_bh(&port->sep_alua_lock);
 754                 list_for_each_entry(se_deve, &port->sep_alua_list,
 755                                         alua_port_list) {
 756                         lacl = se_deve->se_lun_acl;
 757                         /*
 758                          * se_deve->se_lun_acl pointer may be NULL for a
 759                          * entry created without explict Node+MappedLUN ACLs
 760                          */
 761                         if (!(lacl))
 762                                 continue;
 763
 764                         if (explict &&
 765                            (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
 766                            (l_port != NULL) && (l_port == port))
 767                                 continue;
 768
 769                         core_scsi3_ua_allocate(lacl->se_lun_nacl,
 770                                 se_deve->mapped_lun, 0x2A,
 771                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
 772                 }
 773                 spin_unlock_bh(&port->sep_alua_lock);
 774
 775                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 776                 atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
 777                 smp_mb__after_atomic_dec();
 778         }
 779         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 780         /*
 781          * Update the ALUA metadata buf that has been allocated in
 782          * core_alua_do_port_transition(), this metadata will be written
 783          * to struct file.
 784          *
 785          * Note that there is the case where we do not want to update the
 786          * metadata when the saved metadata is being parsed in userspace
 787          * when setting the existing port access state and access status.
 788          *
 789          * Also note that the failure to write out the ALUA metadata to
 790          * struct file does NOT affect the actual ALUA transition.
 791          */
 792         if (tg_pt_gp->tg_pt_gp_write_metadata) {
 793                 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
 794                 core_alua_update_tpg_primary_metadata(tg_pt_gp,
 795                                         new_state, md_buf);
 796                 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
 797         }
 798         /*
 799          * Set the current primary ALUA access state to the requested new state
 800          */
 801         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
 802
 803         printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
 804                 " from primary access state %s to %s\n", (explict) ? "explict" :
 805                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
 806                 tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
 807                 core_alua_dump_state(new_state));
 808
 809         return 0;
 810 }
 811
 812 int core_alua_do_port_transition(
 813         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
 814         struct se_device *l_dev,
 815         struct se_port *l_port,
 816         struct se_node_acl *l_nacl,
 817         int new_state,
 818         int explict)
 819 {
 820         struct se_device *dev;
 821         struct se_port *port;
 822         struct se_subsystem_dev *su_dev;
 823         struct se_node_acl *nacl;
 824         struct t10_alua_lu_gp *lu_gp;
 825         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
 826         struct t10_alua_tg_pt_gp *tg_pt_gp;
 827         unsigned char *md_buf;
 828         int primary;
 829
 830         if (core_alua_check_transition(new_state, &primary) != 0)
 831                 return -EINVAL;
 832
 833         md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
 834         if (!(md_buf)) {
 835                 printk("Unable to allocate buf for ALUA metadata\n");
 836                 return -ENOMEM;
 837         }
 838
 839         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
 840         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
 841         lu_gp = local_lu_gp_mem->lu_gp;
 842         atomic_inc(&lu_gp->lu_gp_ref_cnt);
 843         smp_mb__after_atomic_inc();
 844         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
 845         /*
 846          * For storage objects that are members of the 'default_lu_gp',
 847          * we only do transition on the passed *l_tp_pt_gp, and not
 848          * on all of the matching target port groups IDs in default_lu_gp.
 849          */
 850         if (!(lu_gp->lu_gp_id)) {
 851                 /*
 852                  * core_alua_do_transition_tg_pt() will always return
 853                  * success.
 854                  */
 855                 core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
 856                                         md_buf, new_state, explict);
 857                 atomic_dec(&lu_gp->lu_gp_ref_cnt);
 858                 smp_mb__after_atomic_dec();
 859                 kfree(md_buf);
 860                 return 0;
 861         }
 862         /*
 863          * For all other LU groups aside from 'default_lu_gp', walk all of
 864          * the associated storage objects looking for a matching target port
 865          * group ID from the local target port group.
 866          */
 867         spin_lock(&lu_gp->lu_gp_lock);
 868         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
 869                                 lu_gp_mem_list) {
 870
 871                 dev = lu_gp_mem->lu_gp_mem_dev;
 872                 su_dev = dev->se_sub_dev;
 873                 atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
 874                 smp_mb__after_atomic_inc();
 875                 spin_unlock(&lu_gp->lu_gp_lock);
 876
 877                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 878                 list_for_each_entry(tg_pt_gp,
 879                                 &su_dev->t10_alua.tg_pt_gps_list,
 880                                 tg_pt_gp_list) {
 881
 882                         if (!(tg_pt_gp->tg_pt_gp_valid_id))
 883                                 continue;
 884                         /*
 885                          * If the target behavior port asymmetric access state
 886                          * is changed for any target port group accessiable via
 887                          * a logical unit within a LU group, the target port
 888                          * behavior group asymmetric access states for the same
 889                          * target port group accessible via other logical units
 890                          * in that LU group will also change.
 891                          */
 892                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
 893                                 continue;
 894
 895                         if (l_tg_pt_gp == tg_pt_gp) {
 896                                 port = l_port;
 897                                 nacl = l_nacl;
 898                         } else {
 899                                 port = NULL;
 900                                 nacl = NULL;
 901                         }
 902                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 903                         smp_mb__after_atomic_inc();
 904                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 905                         /*
 906                          * core_alua_do_transition_tg_pt() will always return
 907                          * success.
 908                          */
 909                         core_alua_do_transition_tg_pt(tg_pt_gp, port,
 910                                         nacl, md_buf, new_state, explict);
 911
 912                         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 913                         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 914                         smp_mb__after_atomic_dec();
 915                 }
 916                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 917
 918                 spin_lock(&lu_gp->lu_gp_lock);
 919                 atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
 920                 smp_mb__after_atomic_dec();
 921         }
 922         spin_unlock(&lu_gp->lu_gp_lock);
 923
 924         printk(KERN_INFO "Successfully processed LU Group: %s all ALUA TG PT"
 925                 " Group IDs: %hu %s transition to primary state: %s\n",
 926                 config_item_name(&lu_gp->lu_gp_group.cg_item),
 927                 l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
 928                 core_alua_dump_state(new_state));
 929
 930         atomic_dec(&lu_gp->lu_gp_ref_cnt);
 931         smp_mb__after_atomic_dec();
 932         kfree(md_buf);
 933         return 0;
 934 }
 935
 936 /*
 937  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
 938  */
 939 static int core_alua_update_tpg_secondary_metadata(
 940         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 941         struct se_port *port,
 942         unsigned char *md_buf,
 943         u32 md_buf_len)
 944 {
 945         struct se_portal_group *se_tpg = port->sep_tpg;
 946         char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
 947         int len;
 948
 949         memset(path, 0, ALUA_METADATA_PATH_LEN);
 950         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
 951
 952         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
 953                         se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
 954
 955         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
 956                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
 957                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
 958
 959         len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
 960                         "alua_tg_pt_status=0x%02x\n",
 961                         atomic_read(&port->sep_tg_pt_secondary_offline),
 962                         port->sep_tg_pt_secondary_stat);
 963
 964         snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
 965                         se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
 966                         port->sep_lun->unpacked_lun);
 967
 968         return core_alua_write_tpg_metadata(path, md_buf, len);
 969 }
 970
 971 static int core_alua_set_tg_pt_secondary_state(
 972         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 973         struct se_port *port,
 974         int explict,
 975         int offline)
 976 {
 977         struct t10_alua_tg_pt_gp *tg_pt_gp;
 978         unsigned char *md_buf;
 979         u32 md_buf_len;
 980         int trans_delay_msecs;
 981
 982         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 983         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
 984         if (!(tg_pt_gp)) {
 985                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 986                 printk(KERN_ERR "Unable to complete secondary state"
 987                                 " transition\n");
 988                 return -EINVAL;
 989         }
 990         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
 991         /*
 992          * Set the secondary ALUA target port access state to OFFLINE
 993          * or release the previously secondary state for struct se_port
 994          */
 995         if (offline)
 996                 atomic_set(&port->sep_tg_pt_secondary_offline, 1);
 997         else
 998                 atomic_set(&port->sep_tg_pt_secondary_offline, 0);
 999
1000         md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
1001         port->sep_tg_pt_secondary_stat = (explict) ?
1002                         ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
1003                         ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
1004
1005         printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
1006                 " to secondary access state: %s\n", (explict) ? "explict" :
1007                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1008                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1009
1010         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1011         /*
1012          * Do the optional transition delay after we set the secondary
1013          * ALUA access state.
1014          */
1015         if (trans_delay_msecs != 0)
1016                 msleep_interruptible(trans_delay_msecs);
1017         /*
1018          * See if we need to update the ALUA fabric port metadata for
1019          * secondary state and status
1020          */
1021         if (port->sep_tg_pt_secondary_write_md) {
1022                 md_buf = kzalloc(md_buf_len, GFP_KERNEL);
1023                 if (!(md_buf)) {
1024                         printk(KERN_ERR "Unable to allocate md_buf for"
1025                                 " secondary ALUA access metadata\n");
1026                         return -ENOMEM;
1027                 }
1028                 mutex_lock(&port->sep_tg_pt_md_mutex);
1029                 core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
1030                                 md_buf, md_buf_len);
1031                 mutex_unlock(&port->sep_tg_pt_md_mutex);
1032
1033                 kfree(md_buf);
1034         }
1035
1036         return 0;
1037 }
1038
1039 struct t10_alua_lu_gp *
1040 core_alua_allocate_lu_gp(const char *name, int def_group)
1041 {
1042         struct t10_alua_lu_gp *lu_gp;
1043
1044         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1045         if (!(lu_gp)) {
1046                 printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp\n");
1047                 return ERR_PTR(-ENOMEM);
1048         }
1049         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1050         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1051         spin_lock_init(&lu_gp->lu_gp_lock);
1052         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1053
1054         if (def_group) {
1055                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1056                 lu_gp->lu_gp_valid_id = 1;
1057                 alua_lu_gps_count++;
1058         }
1059
1060         return lu_gp;
1061 }
1062
1063 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1064 {
1065         struct t10_alua_lu_gp *lu_gp_tmp;
1066         u16 lu_gp_id_tmp;
1067         /*
1068          * The lu_gp->lu_gp_id may only be set once..
1069          */
1070         if (lu_gp->lu_gp_valid_id) {
1071                 printk(KERN_WARNING "ALUA LU Group already has a valid ID,"
1072                         " ignoring request\n");
1073                 return -EINVAL;
1074         }
1075
1076         spin_lock(&lu_gps_lock);
1077         if (alua_lu_gps_count == 0x0000ffff) {
1078                 printk(KERN_ERR "Maximum ALUA alua_lu_gps_count:"
1079                                 " 0x0000ffff reached\n");
1080                 spin_unlock(&lu_gps_lock);
1081                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1082                 return -ENOSPC;
1083         }
1084 again:
1085         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1086                                 alua_lu_gps_counter++;
1087
1088         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1089                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1090                         if (!(lu_gp_id))
1091                                 goto again;
1092
1093                         printk(KERN_WARNING "ALUA Logical Unit Group ID: %hu"
1094                                 " already exists, ignoring request\n",
1095                                 lu_gp_id);
1096                         spin_unlock(&lu_gps_lock);
1097                         return -EINVAL;
1098                 }
1099         }
1100
1101         lu_gp->lu_gp_id = lu_gp_id_tmp;
1102         lu_gp->lu_gp_valid_id = 1;
1103         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1104         alua_lu_gps_count++;
1105         spin_unlock(&lu_gps_lock);
1106
1107         return 0;
1108 }
1109
1110 static struct t10_alua_lu_gp_member *
1111 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1112 {
1113         struct t10_alua_lu_gp_member *lu_gp_mem;
1114
1115         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1116         if (!(lu_gp_mem)) {
1117                 printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp_member\n");
1118                 return ERR_PTR(-ENOMEM);
1119         }
1120         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1121         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1122         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1123
1124         lu_gp_mem->lu_gp_mem_dev = dev;
1125         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1126
1127         return lu_gp_mem;
1128 }
1129
1130 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1131 {
1132         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1133         /*
1134          * Once we have reached this point, config_item_put() has
1135          * already been called from target_core_alua_drop_lu_gp().
1136          *
1137          * Here, we remove the *lu_gp from the global list so that
1138          * no associations can be made while we are releasing
1139          * struct t10_alua_lu_gp.
1140          */
1141         spin_lock(&lu_gps_lock);
1142         atomic_set(&lu_gp->lu_gp_shutdown, 1);
1143         list_del(&lu_gp->lu_gp_node);
1144         alua_lu_gps_count--;
1145         spin_unlock(&lu_gps_lock);
1146         /*
1147          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1148          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1149          * released with core_alua_put_lu_gp_from_name()
1150          */
1151         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1152                 cpu_relax();
1153         /*
1154          * Release reference to struct t10_alua_lu_gp * from all associated
1155          * struct se_device.
1156          */
1157         spin_lock(&lu_gp->lu_gp_lock);
1158         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1159                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1160                 if (lu_gp_mem->lu_gp_assoc) {
1161                         list_del(&lu_gp_mem->lu_gp_mem_list);
1162                         lu_gp->lu_gp_members--;
1163                         lu_gp_mem->lu_gp_assoc = 0;
1164                 }
1165                 spin_unlock(&lu_gp->lu_gp_lock);
1166                 /*
1167                  *
1168                  * lu_gp_mem is associated with a single
1169                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1170                  * struct se_device is released via core_alua_free_lu_gp_mem().
1171                  *
1172                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1173                  * we want to re-assocate a given lu_gp_mem with default_lu_gp.
1174                  */
1175                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1176                 if (lu_gp != default_lu_gp)
1177                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1178                                         default_lu_gp);
1179                 else
1180                         lu_gp_mem->lu_gp = NULL;
1181                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1182
1183                 spin_lock(&lu_gp->lu_gp_lock);
1184         }
1185         spin_unlock(&lu_gp->lu_gp_lock);
1186
1187         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1188 }
1189
1190 void core_alua_free_lu_gp_mem(struct se_device *dev)
1191 {
1192         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1193         struct t10_alua *alua = &su_dev->t10_alua;
1194         struct t10_alua_lu_gp *lu_gp;
1195         struct t10_alua_lu_gp_member *lu_gp_mem;
1196
1197         if (alua->alua_type != SPC3_ALUA_EMULATED)
1198                 return;
1199
1200         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1201         if (!(lu_gp_mem))
1202                 return;
1203
1204         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1205                 cpu_relax();
1206
1207         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1208         lu_gp = lu_gp_mem->lu_gp;
1209         if ((lu_gp)) {
1210                 spin_lock(&lu_gp->lu_gp_lock);
1211                 if (lu_gp_mem->lu_gp_assoc) {
1212                         list_del(&lu_gp_mem->lu_gp_mem_list);
1213                         lu_gp->lu_gp_members--;
1214                         lu_gp_mem->lu_gp_assoc = 0;
1215                 }
1216                 spin_unlock(&lu_gp->lu_gp_lock);
1217                 lu_gp_mem->lu_gp = NULL;
1218         }
1219         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1220
1221         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1222 }
1223
1224 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1225 {
1226         struct t10_alua_lu_gp *lu_gp;
1227         struct config_item *ci;
1228
1229         spin_lock(&lu_gps_lock);
1230         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1231                 if (!(lu_gp->lu_gp_valid_id))
1232                         continue;
1233                 ci = &lu_gp->lu_gp_group.cg_item;
1234                 if (!(strcmp(config_item_name(ci), name))) {
1235                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1236                         spin_unlock(&lu_gps_lock);
1237                         return lu_gp;
1238                 }
1239         }
1240         spin_unlock(&lu_gps_lock);
1241
1242         return NULL;
1243 }
1244
1245 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1246 {
1247         spin_lock(&lu_gps_lock);
1248         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1249         spin_unlock(&lu_gps_lock);
1250 }
1251
1252 /*
1253  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1254  */
1255 void __core_alua_attach_lu_gp_mem(
1256         struct t10_alua_lu_gp_member *lu_gp_mem,
1257         struct t10_alua_lu_gp *lu_gp)
1258 {
1259         spin_lock(&lu_gp->lu_gp_lock);
1260         lu_gp_mem->lu_gp = lu_gp;
1261         lu_gp_mem->lu_gp_assoc = 1;
1262         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1263         lu_gp->lu_gp_members++;
1264         spin_unlock(&lu_gp->lu_gp_lock);
1265 }
1266
1267 /*
1268  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1269  */
1270 void __core_alua_drop_lu_gp_mem(
1271         struct t10_alua_lu_gp_member *lu_gp_mem,
1272         struct t10_alua_lu_gp *lu_gp)
1273 {
1274         spin_lock(&lu_gp->lu_gp_lock);
1275         list_del(&lu_gp_mem->lu_gp_mem_list);
1276         lu_gp_mem->lu_gp = NULL;
1277         lu_gp_mem->lu_gp_assoc = 0;
1278         lu_gp->lu_gp_members--;
1279         spin_unlock(&lu_gp->lu_gp_lock);
1280 }
1281
1282 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
1283         struct se_subsystem_dev *su_dev,
1284         const char *name,
1285         int def_group)
1286 {
1287         struct t10_alua_tg_pt_gp *tg_pt_gp;
1288
1289         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1290         if (!(tg_pt_gp)) {
1291                 printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp\n");
1292                 return NULL;
1293         }
1294         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1295         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1296         mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1297         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1298         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1299         tg_pt_gp->tg_pt_gp_su_dev = su_dev;
1300         tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
1301         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1302                 ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
1303         /*
1304          * Enable both explict and implict ALUA support by default
1305          */
1306         tg_pt_gp->tg_pt_gp_alua_access_type =
1307                         TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
1308         /*
1309          * Set the default Active/NonOptimized Delay in milliseconds
1310          */
1311         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1312         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1313
1314         if (def_group) {
1315                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1316                 tg_pt_gp->tg_pt_gp_id =
1317                                 su_dev->t10_alua.alua_tg_pt_gps_counter++;
1318                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1319                 su_dev->t10_alua.alua_tg_pt_gps_count++;
1320                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1321                               &su_dev->t10_alua.tg_pt_gps_list);
1322                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1323         }
1324
1325         return tg_pt_gp;
1326 }
1327
1328 int core_alua_set_tg_pt_gp_id(
1329         struct t10_alua_tg_pt_gp *tg_pt_gp,
1330         u16 tg_pt_gp_id)
1331 {
1332         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1333         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1334         u16 tg_pt_gp_id_tmp;
1335         /*
1336          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1337          */
1338         if (tg_pt_gp->tg_pt_gp_valid_id) {
1339                 printk(KERN_WARNING "ALUA TG PT Group already has a valid ID,"
1340                         " ignoring request\n");
1341                 return -EINVAL;
1342         }
1343
1344         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1345         if (su_dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1346                 printk(KERN_ERR "Maximum ALUA alua_tg_pt_gps_count:"
1347                         " 0x0000ffff reached\n");
1348                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1349                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1350                 return -ENOSPC;
1351         }
1352 again:
1353         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1354                         su_dev->t10_alua.alua_tg_pt_gps_counter++;
1355
1356         list_for_each_entry(tg_pt_gp_tmp, &su_dev->t10_alua.tg_pt_gps_list,
1357                         tg_pt_gp_list) {
1358                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1359                         if (!(tg_pt_gp_id))
1360                                 goto again;
1361
1362                         printk(KERN_ERR "ALUA Target Port Group ID: %hu already"
1363                                 " exists, ignoring request\n", tg_pt_gp_id);
1364                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1365                         return -EINVAL;
1366                 }
1367         }
1368
1369         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1370         tg_pt_gp->tg_pt_gp_valid_id = 1;
1371         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1372                         &su_dev->t10_alua.tg_pt_gps_list);
1373         su_dev->t10_alua.alua_tg_pt_gps_count++;
1374         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1375
1376         return 0;
1377 }
1378
1379 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1380         struct se_port *port)
1381 {
1382         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1383
1384         tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1385                                 GFP_KERNEL);
1386         if (!(tg_pt_gp_mem)) {
1387                 printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1388                 return ERR_PTR(-ENOMEM);
1389         }
1390         INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1391         spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1392         atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1393
1394         tg_pt_gp_mem->tg_pt = port;
1395         port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1396         atomic_set(&port->sep_tg_pt_gp_active, 1);
1397
1398         return tg_pt_gp_mem;
1399 }
1400
1401 void core_alua_free_tg_pt_gp(
1402         struct t10_alua_tg_pt_gp *tg_pt_gp)
1403 {
1404         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1405         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1406         /*
1407          * Once we have reached this point, config_item_put() has already
1408          * been called from target_core_alua_drop_tg_pt_gp().
1409          *
1410          * Here we remove *tg_pt_gp from the global list so that
1411          * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
1412          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1413          */
1414         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1415         list_del(&tg_pt_gp->tg_pt_gp_list);
1416         su_dev->t10_alua.alua_tg_pt_gps_counter--;
1417         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1418         /*
1419          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1420          * core_alua_get_tg_pt_gp_by_name() in
1421          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1422          * to be released with core_alua_put_tg_pt_gp_from_name().
1423          */
1424         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1425                 cpu_relax();
1426         /*
1427          * Release reference to struct t10_alua_tg_pt_gp from all associated
1428          * struct se_port.
1429          */
1430         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1431         list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1432                         &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1433                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1434                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1435                         tg_pt_gp->tg_pt_gp_members--;
1436                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1437                 }
1438                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1439                 /*
1440                  * tg_pt_gp_mem is associated with a single
1441                  * se_port->sep_alua_tg_pt_gp_mem, and is released via
1442                  * core_alua_free_tg_pt_gp_mem().
1443                  *
1444                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1445                  * assume we want to re-assocate a given tg_pt_gp_mem with
1446                  * default_tg_pt_gp.
1447                  */
1448                 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1449                 if (tg_pt_gp != su_dev->t10_alua.default_tg_pt_gp) {
1450                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1451                                         su_dev->t10_alua.default_tg_pt_gp);
1452                 } else
1453                         tg_pt_gp_mem->tg_pt_gp = NULL;
1454                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1455
1456                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1457         }
1458         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1459
1460         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1461 }
1462
1463 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1464 {
1465         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1466         struct t10_alua *alua = &su_dev->t10_alua;
1467         struct t10_alua_tg_pt_gp *tg_pt_gp;
1468         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1469
1470         if (alua->alua_type != SPC3_ALUA_EMULATED)
1471                 return;
1472
1473         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1474         if (!(tg_pt_gp_mem))
1475                 return;
1476
1477         while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1478                 cpu_relax();
1479
1480         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1481         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1482         if ((tg_pt_gp)) {
1483                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1484                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1485                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1486                         tg_pt_gp->tg_pt_gp_members--;
1487                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1488                 }
1489                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1490                 tg_pt_gp_mem->tg_pt_gp = NULL;
1491         }
1492         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1493
1494         kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1495 }
1496
1497 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1498         struct se_subsystem_dev *su_dev,
1499         const char *name)
1500 {
1501         struct t10_alua_tg_pt_gp *tg_pt_gp;
1502         struct config_item *ci;
1503
1504         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1505         list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
1506                         tg_pt_gp_list) {
1507                 if (!(tg_pt_gp->tg_pt_gp_valid_id))
1508                         continue;
1509                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1510                 if (!(strcmp(config_item_name(ci), name))) {
1511                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1512                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1513                         return tg_pt_gp;
1514                 }
1515         }
1516         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1517
1518         return NULL;
1519 }
1520
1521 static void core_alua_put_tg_pt_gp_from_name(
1522         struct t10_alua_tg_pt_gp *tg_pt_gp)
1523 {
1524         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1525
1526         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1527         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1528         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1529 }
1530
1531 /*
1532  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1533  */
1534 void __core_alua_attach_tg_pt_gp_mem(
1535         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1536         struct t10_alua_tg_pt_gp *tg_pt_gp)
1537 {
1538         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1539         tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1540         tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1541         list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1542                         &tg_pt_gp->tg_pt_gp_mem_list);
1543         tg_pt_gp->tg_pt_gp_members++;
1544         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1545 }
1546
1547 /*
1548  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1549  */
1550 static void __core_alua_drop_tg_pt_gp_mem(
1551         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1552         struct t10_alua_tg_pt_gp *tg_pt_gp)
1553 {
1554         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1555         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1556         tg_pt_gp_mem->tg_pt_gp = NULL;
1557         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1558         tg_pt_gp->tg_pt_gp_members--;
1559         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1560 }
1561
1562 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1563 {
1564         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1565         struct config_item *tg_pt_ci;
1566         struct t10_alua *alua = &su_dev->t10_alua;
1567         struct t10_alua_tg_pt_gp *tg_pt_gp;
1568         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1569         ssize_t len = 0;
1570
1571         if (alua->alua_type != SPC3_ALUA_EMULATED)
1572                 return len;
1573
1574         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1575         if (!(tg_pt_gp_mem))
1576                 return len;
1577
1578         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1579         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1580         if ((tg_pt_gp)) {
1581                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1582                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1583                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1584                         "Primary Access Status: %s\nTG Port Secondary Access"
1585                         " State: %s\nTG Port Secondary Access Status: %s\n",
1586                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1587                         core_alua_dump_state(atomic_read(
1588                                         &tg_pt_gp->tg_pt_gp_alua_access_state)),
1589                         core_alua_dump_status(
1590                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1591                         (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
1592                         "Offline" : "None",
1593                         core_alua_dump_status(port->sep_tg_pt_secondary_stat));
1594         }
1595         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1596
1597         return len;
1598 }
1599
1600 ssize_t core_alua_store_tg_pt_gp_info(
1601         struct se_port *port,
1602         const char *page,
1603         size_t count)
1604 {
1605         struct se_portal_group *tpg;
1606         struct se_lun *lun;
1607         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1608         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1609         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1610         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1611         int move = 0;
1612
1613         tpg = port->sep_tpg;
1614         lun = port->sep_lun;
1615
1616         if (su_dev->t10_alua.alua_type != SPC3_ALUA_EMULATED) {
1617                 printk(KERN_WARNING "SPC3_ALUA_EMULATED not enabled for"
1618                         " %s/tpgt_%hu/%s\n", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1619                         tpg->se_tpg_tfo->tpg_get_tag(tpg),
1620                         config_item_name(&lun->lun_group.cg_item));
1621                 return -EINVAL;
1622         }
1623
1624         if (count > TG_PT_GROUP_NAME_BUF) {
1625                 printk(KERN_ERR "ALUA Target Port Group alias too large!\n");
1626                 return -EINVAL;
1627         }
1628         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1629         memcpy(buf, page, count);
1630         /*
1631          * Any ALUA target port group alias besides "NULL" means we will be
1632          * making a new group association.
1633          */
1634         if (strcmp(strstrip(buf), "NULL")) {
1635                 /*
1636                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1637                  * struct t10_alua_tg_pt_gp.  This reference is released with
1638                  * core_alua_put_tg_pt_gp_from_name() below.
1639                  */
1640                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
1641                                         strstrip(buf));
1642                 if (!(tg_pt_gp_new))
1643                         return -ENODEV;
1644         }
1645         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1646         if (!(tg_pt_gp_mem)) {
1647                 if (tg_pt_gp_new)
1648                         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1649                 printk(KERN_ERR "NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
1650                 return -EINVAL;
1651         }
1652
1653         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1654         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1655         if ((tg_pt_gp)) {
1656                 /*
1657                  * Clearing an existing tg_pt_gp association, and replacing
1658                  * with the default_tg_pt_gp.
1659                  */
1660                 if (!(tg_pt_gp_new)) {
1661                         printk(KERN_INFO "Target_Core_ConfigFS: Moving"
1662                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1663                                 " alua/%s, ID: %hu back to"
1664                                 " default_tg_pt_gp\n",
1665                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1666                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1667                                 config_item_name(&lun->lun_group.cg_item),
1668                                 config_item_name(
1669                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1670                                 tg_pt_gp->tg_pt_gp_id);
1671
1672                         __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1673                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1674                                         su_dev->t10_alua.default_tg_pt_gp);
1675                         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1676
1677                         return count;
1678                 }
1679                 /*
1680                  * Removing existing association of tg_pt_gp_mem with tg_pt_gp
1681                  */
1682                 __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1683                 move = 1;
1684         }
1685         /*
1686          * Associate tg_pt_gp_mem with tg_pt_gp_new.
1687          */
1688         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
1689         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1690         printk(KERN_INFO "Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1691                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1692                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1693                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1694                 config_item_name(&lun->lun_group.cg_item),
1695                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1696                 tg_pt_gp_new->tg_pt_gp_id);
1697
1698         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1699         return count;
1700 }
1701
1702 ssize_t core_alua_show_access_type(
1703         struct t10_alua_tg_pt_gp *tg_pt_gp,
1704         char *page)
1705 {
1706         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
1707             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
1708                 return sprintf(page, "Implict and Explict\n");
1709         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
1710                 return sprintf(page, "Implict\n");
1711         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
1712                 return sprintf(page, "Explict\n");
1713         else
1714                 return sprintf(page, "None\n");
1715 }
1716
1717 ssize_t core_alua_store_access_type(
1718         struct t10_alua_tg_pt_gp *tg_pt_gp,
1719         const char *page,
1720         size_t count)
1721 {
1722         unsigned long tmp;
1723         int ret;
1724
1725         ret = strict_strtoul(page, 0, &tmp);
1726         if (ret < 0) {
1727                 printk(KERN_ERR "Unable to extract alua_access_type\n");
1728                 return -EINVAL;
1729         }
1730         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
1731                 printk(KERN_ERR "Illegal value for alua_access_type:"
1732                                 " %lu\n", tmp);
1733                 return -EINVAL;
1734         }
1735         if (tmp == 3)
1736                 tg_pt_gp->tg_pt_gp_alua_access_type =
1737                         TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
1738         else if (tmp == 2)
1739                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
1740         else if (tmp == 1)
1741                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
1742         else
1743                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
1744
1745         return count;
1746 }
1747
1748 ssize_t core_alua_show_nonop_delay_msecs(
1749         struct t10_alua_tg_pt_gp *tg_pt_gp,
1750         char *page)
1751 {
1752         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
1753 }
1754
1755 ssize_t core_alua_store_nonop_delay_msecs(
1756         struct t10_alua_tg_pt_gp *tg_pt_gp,
1757         const char *page,
1758         size_t count)
1759 {
1760         unsigned long tmp;
1761         int ret;
1762
1763         ret = strict_strtoul(page, 0, &tmp);
1764         if (ret < 0) {
1765                 printk(KERN_ERR "Unable to extract nonop_delay_msecs\n");
1766                 return -EINVAL;
1767         }
1768         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
1769                 printk(KERN_ERR "Passed nonop_delay_msecs: %lu, exceeds"
1770                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
1771                         ALUA_MAX_NONOP_DELAY_MSECS);
1772                 return -EINVAL;
1773         }
1774         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
1775
1776         return count;
1777 }
1778
1779 ssize_t core_alua_show_trans_delay_msecs(
1780         struct t10_alua_tg_pt_gp *tg_pt_gp,
1781         char *page)
1782 {
1783         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1784 }
1785
1786 ssize_t core_alua_store_trans_delay_msecs(
1787         struct t10_alua_tg_pt_gp *tg_pt_gp,
1788         const char *page,
1789         size_t count)
1790 {
1791         unsigned long tmp;
1792         int ret;
1793
1794         ret = strict_strtoul(page, 0, &tmp);
1795         if (ret < 0) {
1796                 printk(KERN_ERR "Unable to extract trans_delay_msecs\n");
1797                 return -EINVAL;
1798         }
1799         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
1800                 printk(KERN_ERR "Passed trans_delay_msecs: %lu, exceeds"
1801                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
1802                         ALUA_MAX_TRANS_DELAY_MSECS);
1803                 return -EINVAL;
1804         }
1805         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
1806
1807         return count;
1808 }
1809
1810 ssize_t core_alua_show_preferred_bit(
1811         struct t10_alua_tg_pt_gp *tg_pt_gp,
1812         char *page)
1813 {
1814         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
1815 }
1816
1817 ssize_t core_alua_store_preferred_bit(
1818         struct t10_alua_tg_pt_gp *tg_pt_gp,
1819         const char *page,
1820         size_t count)
1821 {
1822         unsigned long tmp;
1823         int ret;
1824
1825         ret = strict_strtoul(page, 0, &tmp);
1826         if (ret < 0) {
1827                 printk(KERN_ERR "Unable to extract preferred ALUA value\n");
1828                 return -EINVAL;
1829         }
1830         if ((tmp != 0) && (tmp != 1)) {
1831                 printk(KERN_ERR "Illegal value for preferred ALUA: %lu\n", tmp);
1832                 return -EINVAL;
1833         }
1834         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
1835
1836         return count;
1837 }
1838
1839 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
1840 {
1841         if (!(lun->lun_sep))
1842                 return -ENODEV;
1843
1844         return sprintf(page, "%d\n",
1845                 atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
1846 }
1847
1848 ssize_t core_alua_store_offline_bit(
1849         struct se_lun *lun,
1850         const char *page,
1851         size_t count)
1852 {
1853         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1854         unsigned long tmp;
1855         int ret;
1856
1857         if (!(lun->lun_sep))
1858                 return -ENODEV;
1859
1860         ret = strict_strtoul(page, 0, &tmp);
1861         if (ret < 0) {
1862                 printk(KERN_ERR "Unable to extract alua_tg_pt_offline value\n");
1863                 return -EINVAL;
1864         }
1865         if ((tmp != 0) && (tmp != 1)) {
1866                 printk(KERN_ERR "Illegal value for alua_tg_pt_offline: %lu\n",
1867                                 tmp);
1868                 return -EINVAL;
1869         }
1870         tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
1871         if (!(tg_pt_gp_mem)) {
1872                 printk(KERN_ERR "Unable to locate *tg_pt_gp_mem\n");
1873                 return -EINVAL;
1874         }
1875
1876         ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
1877                         lun->lun_sep, 0, (int)tmp);
1878         if (ret < 0)
1879                 return -EINVAL;
1880
1881         return count;
1882 }
1883
1884 ssize_t core_alua_show_secondary_status(
1885         struct se_lun *lun,
1886         char *page)
1887 {
1888         return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
1889 }
1890
1891 ssize_t core_alua_store_secondary_status(
1892         struct se_lun *lun,
1893         const char *page,
1894         size_t count)
1895 {
1896         unsigned long tmp;
1897         int ret;
1898
1899         ret = strict_strtoul(page, 0, &tmp);
1900         if (ret < 0) {
1901                 printk(KERN_ERR "Unable to extract alua_tg_pt_status\n");
1902                 return -EINVAL;
1903         }
1904         if ((tmp != ALUA_STATUS_NONE) &&
1905             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
1906             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
1907                 printk(KERN_ERR "Illegal value for alua_tg_pt_status: %lu\n",
1908                                 tmp);
1909                 return -EINVAL;
1910         }
1911         lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
1912
1913         return count;
1914 }
1915
1916 ssize_t core_alua_show_secondary_write_metadata(
1917         struct se_lun *lun,
1918         char *page)
1919 {
1920         return sprintf(page, "%d\n",
1921                         lun->lun_sep->sep_tg_pt_secondary_write_md);
1922 }
1923
1924 ssize_t core_alua_store_secondary_write_metadata(
1925         struct se_lun *lun,
1926         const char *page,
1927         size_t count)
1928 {
1929         unsigned long tmp;
1930         int ret;
1931
1932         ret = strict_strtoul(page, 0, &tmp);
1933         if (ret < 0) {
1934                 printk(KERN_ERR "Unable to extract alua_tg_pt_write_md\n");
1935                 return -EINVAL;
1936         }
1937         if ((tmp != 0) && (tmp != 1)) {
1938                 printk(KERN_ERR "Illegal value for alua_tg_pt_write_md:"
1939                                 " %lu\n", tmp);
1940                 return -EINVAL;
1941         }
1942         lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
1943
1944         return count;
1945 }
1946
1947 int core_setup_alua(struct se_device *dev, int force_pt)
1948 {
1949         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1950         struct t10_alua *alua = &su_dev->t10_alua;
1951         struct t10_alua_lu_gp_member *lu_gp_mem;
1952         /*
1953          * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
1954          * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
1955          * cause a problem because libata and some SATA RAID HBAs appear
1956          * under Linux/SCSI, but emulate SCSI logic themselves.
1957          */
1958         if (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
1959             !(dev->se_sub_dev->se_dev_attrib.emulate_alua)) || force_pt) {
1960                 alua->alua_type = SPC_ALUA_PASSTHROUGH;
1961                 alua->alua_state_check = &core_alua_state_check_nop;
1962                 printk(KERN_INFO "%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
1963                         " emulation\n", dev->transport->name);
1964                 return 0;
1965         }
1966         /*
1967          * If SPC-3 or above is reported by real or emulated struct se_device,
1968          * use emulated ALUA.
1969          */
1970         if (dev->transport->get_device_rev(dev) >= SCSI_3) {
1971                 printk(KERN_INFO "%s: Enabling ALUA Emulation for SPC-3"
1972                         " device\n", dev->transport->name);
1973                 /*
1974                  * Associate this struct se_device with the default ALUA
1975                  * LUN Group.
1976                  */
1977                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
1978                 if (IS_ERR(lu_gp_mem))
1979                         return PTR_ERR(lu_gp_mem);
1980
1981                 alua->alua_type = SPC3_ALUA_EMULATED;
1982                 alua->alua_state_check = &core_alua_state_check;
1983                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1984                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
1985                                 default_lu_gp);
1986                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1987
1988                 printk(KERN_INFO "%s: Adding to default ALUA LU Group:"
1989                         " core/alua/lu_gps/default_lu_gp\n",
1990                         dev->transport->name);
1991         } else {
1992                 alua->alua_type = SPC2_ALUA_DISABLED;
1993                 alua->alua_state_check = &core_alua_state_check_nop;
1994                 printk(KERN_INFO "%s: Disabling ALUA Emulation for SPC-2"
1995                         " device\n", dev->transport->name);
1996         }
1997
1998         return 0;
1999 }