drivers/target/target_core_alua.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * Filename:  target_core_alua.c
   4  *
   5  * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
   6  *
   7  * (c) Copyright 2009-2013 Datera, Inc.
   8  *
   9  * Nicholas A. Bellinger <[email protected]>
  10  *
  11  ******************************************************************************/
  12
  13 #include <linux/slab.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/configfs.h>
  16 #include <linux/delay.h>
  17 #include <linux/export.h>
  18 #include <linux/fcntl.h>
  19 #include <linux/file.h>
  20 #include <linux/fs.h>
  21 #include <scsi/scsi_proto.h>
  22 #include <asm/unaligned.h>
  23
  24 #include <target/target_core_base.h>
  25 #include <target/target_core_backend.h>
  26 #include <target/target_core_fabric.h>
  27
  28 #include "target_core_internal.h"
  29 #include "target_core_alua.h"
  30 #include "target_core_ua.h"
  31
  32 static sense_reason_t core_alua_check_transition(int state, int valid,
  33                                                  int *primary, int explicit);
  34 static int core_alua_set_tg_pt_secondary_state(
  35                 struct se_lun *lun, int explicit, int offline);
  36
  37 static char *core_alua_dump_state(int state);
  38
  39 static void __target_attach_tg_pt_gp(struct se_lun *lun,
  40                 struct t10_alua_tg_pt_gp *tg_pt_gp);
  41
  42 static u16 alua_lu_gps_counter;
  43 static u32 alua_lu_gps_count;
  44
  45 static DEFINE_SPINLOCK(lu_gps_lock);
  46 static LIST_HEAD(lu_gps_list);
  47
  48 struct t10_alua_lu_gp *default_lu_gp;
  49
  50 /*
  51  * REPORT REFERRALS
  52  *
  53  * See sbc3r35 section 5.23
  54  */
  55 sense_reason_t
  56 target_emulate_report_referrals(struct se_cmd *cmd)
  57 {
  58         struct se_device *dev = cmd->se_dev;
  59         struct t10_alua_lba_map *map;
  60         struct t10_alua_lba_map_member *map_mem;
  61         unsigned char *buf;
  62         u32 rd_len = 0, off;
  63
  64         if (cmd->data_length < 4) {
  65                 pr_warn("REPORT REFERRALS allocation length %u too"
  66                         " small\n", cmd->data_length);
  67                 return TCM_INVALID_CDB_FIELD;
  68         }
  69
  70         buf = transport_kmap_data_sg(cmd);
  71         if (!buf)
  72                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
  73
  74         off = 4;
  75         spin_lock(&dev->t10_alua.lba_map_lock);
  76         if (list_empty(&dev->t10_alua.lba_map_list)) {
  77                 spin_unlock(&dev->t10_alua.lba_map_lock);
  78                 transport_kunmap_data_sg(cmd);
  79
  80                 return TCM_UNSUPPORTED_SCSI_OPCODE;
  81         }
  82
  83         list_for_each_entry(map, &dev->t10_alua.lba_map_list,
  84                             lba_map_list) {
  85                 int desc_num = off + 3;
  86                 int pg_num;
  87
  88                 off += 4;
  89                 if (cmd->data_length > off)
  90                         put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
  91                 off += 8;
  92                 if (cmd->data_length > off)
  93                         put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
  94                 off += 8;
  95                 rd_len += 20;
  96                 pg_num = 0;
  97                 list_for_each_entry(map_mem, &map->lba_map_mem_list,
  98                                     lba_map_mem_list) {
  99                         int alua_state = map_mem->lba_map_mem_alua_state;
 100                         int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
 101
 102                         if (cmd->data_length > off)
 103                                 buf[off] = alua_state & 0x0f;
 104                         off += 2;
 105                         if (cmd->data_length > off)
 106                                 buf[off] = (alua_pg_id >> 8) & 0xff;
 107                         off++;
 108                         if (cmd->data_length > off)
 109                                 buf[off] = (alua_pg_id & 0xff);
 110                         off++;
 111                         rd_len += 4;
 112                         pg_num++;
 113                 }
 114                 if (cmd->data_length > desc_num)
 115                         buf[desc_num] = pg_num;
 116         }
 117         spin_unlock(&dev->t10_alua.lba_map_lock);
 118
 119         /*
 120          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 121          */
 122         put_unaligned_be16(rd_len, &buf[2]);
 123
 124         transport_kunmap_data_sg(cmd);
 125
 126         target_complete_cmd(cmd, SAM_STAT_GOOD);
 127         return 0;
 128 }
 129
 130 /*
 131  * REPORT_TARGET_PORT_GROUPS
 132  *
 133  * See spc4r17 section 6.27
 134  */
 135 sense_reason_t
 136 target_emulate_report_target_port_groups(struct se_cmd *cmd)
 137 {
 138         struct se_device *dev = cmd->se_dev;
 139         struct t10_alua_tg_pt_gp *tg_pt_gp;
 140         struct se_lun *lun;
 141         unsigned char *buf;
 142         u32 rd_len = 0, off;
 143         int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
 144
 145         /*
 146          * Skip over RESERVED area to first Target port group descriptor
 147          * depending on the PARAMETER DATA FORMAT type..
 148          */
 149         if (ext_hdr != 0)
 150                 off = 8;
 151         else
 152                 off = 4;
 153
 154         if (cmd->data_length < off) {
 155                 pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
 156                         " small for %s header\n", cmd->data_length,
 157                         (ext_hdr) ? "extended" : "normal");
 158                 return TCM_INVALID_CDB_FIELD;
 159         }
 160         buf = transport_kmap_data_sg(cmd);
 161         if (!buf)
 162                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 163
 164         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 165         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
 166                         tg_pt_gp_list) {
 167                 /* Skip empty port groups */
 168                 if (!tg_pt_gp->tg_pt_gp_members)
 169                         continue;
 170                 /*
 171                  * Check if the Target port group and Target port descriptor list
 172                  * based on tg_pt_gp_members count will fit into the response payload.
 173                  * Otherwise, bump rd_len to let the initiator know we have exceeded
 174                  * the allocation length and the response is truncated.
 175                  */
 176                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
 177                      cmd->data_length) {
 178                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
 179                         continue;
 180                 }
 181                 /*
 182                  * PREF: Preferred target port bit, determine if this
 183                  * bit should be set for port group.
 184                  */
 185                 if (tg_pt_gp->tg_pt_gp_pref)
 186                         buf[off] = 0x80;
 187                 /*
 188                  * Set the ASYMMETRIC ACCESS State
 189                  */
 190                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_access_state & 0xff;
 191                 /*
 192                  * Set supported ASYMMETRIC ACCESS State bits
 193                  */
 194                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
 195                 /*
 196                  * TARGET PORT GROUP
 197                  */
 198                 put_unaligned_be16(tg_pt_gp->tg_pt_gp_id, &buf[off]);
 199                 off += 2;
 200
 201                 off++; /* Skip over Reserved */
 202                 /*
 203                  * STATUS CODE
 204                  */
 205                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 206                 /*
 207                  * Vendor Specific field
 208                  */
 209                 buf[off++] = 0x00;
 210                 /*
 211                  * TARGET PORT COUNT
 212                  */
 213                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 214                 rd_len += 8;
 215
 216                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 217                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 218                                 lun_tg_pt_gp_link) {
 219                         /*
 220                          * Start Target Port descriptor format
 221                          *
 222                          * See spc4r17 section 6.2.7 Table 247
 223                          */
 224                         off += 2; /* Skip over Obsolete */
 225                         /*
 226                          * Set RELATIVE TARGET PORT IDENTIFIER
 227                          */
 228                         put_unaligned_be16(lun->lun_tpg->tpg_rtpi, &buf[off]);
 229                         off += 2;
 230                         rd_len += 4;
 231                 }
 232                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 233         }
 234         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 235         /*
 236          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 237          */
 238         put_unaligned_be32(rd_len, &buf[0]);
 239
 240         /*
 241          * Fill in the Extended header parameter data format if requested
 242          */
 243         if (ext_hdr != 0) {
 244                 buf[4] = 0x10;
 245                 /*
 246                  * Set the implicit transition time (in seconds) for the application
 247                  * client to use as a base for it's transition timeout value.
 248                  *
 249                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
 250                  * this CDB was received upon to determine this value individually
 251                  * for ALUA target port group.
 252                  */
 253                 rcu_read_lock();
 254                 tg_pt_gp = rcu_dereference(cmd->se_lun->lun_tg_pt_gp);
 255                 if (tg_pt_gp)
 256                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
 257                 rcu_read_unlock();
 258         }
 259         transport_kunmap_data_sg(cmd);
 260
 261         target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, rd_len + 4);
 262         return 0;
 263 }
 264
 265 /*
 266  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
 267  *
 268  * See spc4r17 section 6.35
 269  */
 270 sense_reason_t
 271 target_emulate_set_target_port_groups(struct se_cmd *cmd)
 272 {
 273         struct se_device *dev = cmd->se_dev;
 274         struct se_lun *l_lun = cmd->se_lun;
 275         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 276         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 277         unsigned char *buf;
 278         unsigned char *ptr;
 279         sense_reason_t rc = TCM_NO_SENSE;
 280         u32 len = 4; /* Skip over RESERVED area in header */
 281         int alua_access_state, primary = 0, valid_states;
 282         u16 tg_pt_id, rtpi;
 283
 284         if (cmd->data_length < 4) {
 285                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
 286                         " small\n", cmd->data_length);
 287                 return TCM_INVALID_PARAMETER_LIST;
 288         }
 289
 290         buf = transport_kmap_data_sg(cmd);
 291         if (!buf)
 292                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 293
 294         /*
 295          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
 296          * for the local tg_pt_gp.
 297          */
 298         rcu_read_lock();
 299         l_tg_pt_gp = rcu_dereference(l_lun->lun_tg_pt_gp);
 300         if (!l_tg_pt_gp) {
 301                 rcu_read_unlock();
 302                 pr_err("Unable to access l_lun->tg_pt_gp\n");
 303                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 304                 goto out;
 305         }
 306
 307         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
 308                 rcu_read_unlock();
 309                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 310                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
 311                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 312                 goto out;
 313         }
 314         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
 315         rcu_read_unlock();
 316
 317         ptr = &buf[4]; /* Skip over RESERVED area in header */
 318
 319         while (len < cmd->data_length) {
 320                 bool found = false;
 321                 alua_access_state = (ptr[0] & 0x0f);
 322                 /*
 323                  * Check the received ALUA access state, and determine if
 324                  * the state is a primary or secondary target port asymmetric
 325                  * access state.
 326                  */
 327                 rc = core_alua_check_transition(alua_access_state, valid_states,
 328                                                 &primary, 1);
 329                 if (rc) {
 330                         /*
 331                          * If the SET TARGET PORT GROUPS attempts to establish
 332                          * an invalid combination of target port asymmetric
 333                          * access states or attempts to establish an
 334                          * unsupported target port asymmetric access state,
 335                          * then the command shall be terminated with CHECK
 336                          * CONDITION status, with the sense key set to ILLEGAL
 337                          * REQUEST, and the additional sense code set to INVALID
 338                          * FIELD IN PARAMETER LIST.
 339                          */
 340                         goto out;
 341                 }
 342
 343                 /*
 344                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 345                  * specifies a primary target port asymmetric access state,
 346                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 347                  * a primary target port group for which the primary target
 348                  * port asymmetric access state shall be changed. If the
 349                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 350                  * port asymmetric access state, then the TARGET PORT GROUP OR
 351                  * TARGET PORT field specifies the relative target port
 352                  * identifier (see 3.1.120) of the target port for which the
 353                  * secondary target port asymmetric access state shall be
 354                  * changed.
 355                  */
 356                 if (primary) {
 357                         tg_pt_id = get_unaligned_be16(ptr + 2);
 358                         /*
 359                          * Locate the matching target port group ID from
 360                          * the global tg_pt_gp list
 361                          */
 362                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 363                         list_for_each_entry(tg_pt_gp,
 364                                         &dev->t10_alua.tg_pt_gps_list,
 365                                         tg_pt_gp_list) {
 366                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 367                                         continue;
 368
 369                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 370                                         continue;
 371
 372                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 373
 374                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 375
 376                                 if (!core_alua_do_port_transition(tg_pt_gp,
 377                                                 dev, l_lun, nacl,
 378                                                 alua_access_state, 1))
 379                                         found = true;
 380
 381                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 382                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 383                                 break;
 384                         }
 385                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 386                 } else {
 387                         struct se_lun *lun;
 388
 389                         /*
 390                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
 391                          * the Target Port in question for the incoming
 392                          * SET_TARGET_PORT_GROUPS op.
 393                          */
 394                         rtpi = get_unaligned_be16(ptr + 2);
 395                         /*
 396                          * Locate the matching relative target port identifier
 397                          * for the struct se_device storage object.
 398                          */
 399                         spin_lock(&dev->se_port_lock);
 400                         list_for_each_entry(lun, &dev->dev_sep_list,
 401                                                         lun_dev_link) {
 402                                 if (lun->lun_tpg->tpg_rtpi != rtpi)
 403                                         continue;
 404
 405                                 // XXX: racy unlock
 406                                 spin_unlock(&dev->se_port_lock);
 407
 408                                 if (!core_alua_set_tg_pt_secondary_state(
 409                                                 lun, 1, 1))
 410                                         found = true;
 411
 412                                 spin_lock(&dev->se_port_lock);
 413                                 break;
 414                         }
 415                         spin_unlock(&dev->se_port_lock);
 416                 }
 417
 418                 if (!found) {
 419                         rc = TCM_INVALID_PARAMETER_LIST;
 420                         goto out;
 421                 }
 422
 423                 ptr += 4;
 424                 len += 4;
 425         }
 426
 427 out:
 428         transport_kunmap_data_sg(cmd);
 429         if (!rc)
 430                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 431         return rc;
 432 }
 433
 434 static inline void core_alua_state_nonoptimized(
 435         struct se_cmd *cmd,
 436         unsigned char *cdb,
 437         int nonop_delay_msecs)
 438 {
 439         /*
 440          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 441          * later to determine if processing of this cmd needs to be
 442          * temporarily delayed for the Active/NonOptimized primary access state.
 443          */
 444         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 445         cmd->alua_nonop_delay = nonop_delay_msecs;
 446 }
 447
 448 static inline sense_reason_t core_alua_state_lba_dependent(
 449         struct se_cmd *cmd,
 450         u16 tg_pt_gp_id)
 451 {
 452         struct se_device *dev = cmd->se_dev;
 453         u64 segment_size, segment_mult, sectors, lba;
 454
 455         /* Only need to check for cdb actually containing LBAs */
 456         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
 457                 return 0;
 458
 459         spin_lock(&dev->t10_alua.lba_map_lock);
 460         segment_size = dev->t10_alua.lba_map_segment_size;
 461         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
 462         sectors = cmd->data_length / dev->dev_attrib.block_size;
 463
 464         lba = cmd->t_task_lba;
 465         while (lba < cmd->t_task_lba + sectors) {
 466                 struct t10_alua_lba_map *cur_map = NULL, *map;
 467                 struct t10_alua_lba_map_member *map_mem;
 468
 469                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
 470                                     lba_map_list) {
 471                         u64 start_lba, last_lba;
 472                         u64 first_lba = map->lba_map_first_lba;
 473
 474                         if (segment_mult) {
 475                                 u64 tmp = lba;
 476                                 start_lba = do_div(tmp, segment_size * segment_mult);
 477
 478                                 last_lba = first_lba + segment_size - 1;
 479                                 if (start_lba >= first_lba &&
 480                                     start_lba <= last_lba) {
 481                                         lba += segment_size;
 482                                         cur_map = map;
 483                                         break;
 484                                 }
 485                         } else {
 486                                 last_lba = map->lba_map_last_lba;
 487                                 if (lba >= first_lba && lba <= last_lba) {
 488                                         lba = last_lba + 1;
 489                                         cur_map = map;
 490                                         break;
 491                                 }
 492                         }
 493                 }
 494                 if (!cur_map) {
 495                         spin_unlock(&dev->t10_alua.lba_map_lock);
 496                         return TCM_ALUA_TG_PT_UNAVAILABLE;
 497                 }
 498                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
 499                                     lba_map_mem_list) {
 500                         if (map_mem->lba_map_mem_alua_pg_id != tg_pt_gp_id)
 501                                 continue;
 502                         switch(map_mem->lba_map_mem_alua_state) {
 503                         case ALUA_ACCESS_STATE_STANDBY:
 504                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 505                                 return TCM_ALUA_TG_PT_STANDBY;
 506                         case ALUA_ACCESS_STATE_UNAVAILABLE:
 507                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 508                                 return TCM_ALUA_TG_PT_UNAVAILABLE;
 509                         default:
 510                                 break;
 511                         }
 512                 }
 513         }
 514         spin_unlock(&dev->t10_alua.lba_map_lock);
 515         return 0;
 516 }
 517
 518 static inline sense_reason_t core_alua_state_standby(
 519         struct se_cmd *cmd,
 520         unsigned char *cdb)
 521 {
 522         /*
 523          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 524          * spc4r17 section 5.9.2.4.4
 525          */
 526         switch (cdb[0]) {
 527         case INQUIRY:
 528         case LOG_SELECT:
 529         case LOG_SENSE:
 530         case MODE_SELECT:
 531         case MODE_SENSE:
 532         case REPORT_LUNS:
 533         case RECEIVE_DIAGNOSTIC:
 534         case SEND_DIAGNOSTIC:
 535         case READ_CAPACITY:
 536                 return 0;
 537         case SERVICE_ACTION_IN_16:
 538                 switch (cdb[1] & 0x1f) {
 539                 case SAI_READ_CAPACITY_16:
 540                         return 0;
 541                 default:
 542                         return TCM_ALUA_TG_PT_STANDBY;
 543                 }
 544         case MAINTENANCE_IN:
 545                 switch (cdb[1] & 0x1f) {
 546                 case MI_REPORT_TARGET_PGS:
 547                         return 0;
 548                 default:
 549                         return TCM_ALUA_TG_PT_STANDBY;
 550                 }
 551         case MAINTENANCE_OUT:
 552                 switch (cdb[1]) {
 553                 case MO_SET_TARGET_PGS:
 554                         return 0;
 555                 default:
 556                         return TCM_ALUA_TG_PT_STANDBY;
 557                 }
 558         case REQUEST_SENSE:
 559         case PERSISTENT_RESERVE_IN:
 560         case PERSISTENT_RESERVE_OUT:
 561         case READ_BUFFER:
 562         case WRITE_BUFFER:
 563                 return 0;
 564         default:
 565                 return TCM_ALUA_TG_PT_STANDBY;
 566         }
 567
 568         return 0;
 569 }
 570
 571 static inline sense_reason_t core_alua_state_unavailable(
 572         struct se_cmd *cmd,
 573         unsigned char *cdb)
 574 {
 575         /*
 576          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 577          * spc4r17 section 5.9.2.4.5
 578          */
 579         switch (cdb[0]) {
 580         case INQUIRY:
 581         case REPORT_LUNS:
 582                 return 0;
 583         case MAINTENANCE_IN:
 584                 switch (cdb[1] & 0x1f) {
 585                 case MI_REPORT_TARGET_PGS:
 586                         return 0;
 587                 default:
 588                         return TCM_ALUA_TG_PT_UNAVAILABLE;
 589                 }
 590         case MAINTENANCE_OUT:
 591                 switch (cdb[1]) {
 592                 case MO_SET_TARGET_PGS:
 593                         return 0;
 594                 default:
 595                         return TCM_ALUA_TG_PT_UNAVAILABLE;
 596                 }
 597         case REQUEST_SENSE:
 598         case READ_BUFFER:
 599         case WRITE_BUFFER:
 600                 return 0;
 601         default:
 602                 return TCM_ALUA_TG_PT_UNAVAILABLE;
 603         }
 604
 605         return 0;
 606 }
 607
 608 static inline sense_reason_t core_alua_state_transition(
 609         struct se_cmd *cmd,
 610         unsigned char *cdb)
 611 {
 612         /*
 613          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
 614          * spc4r17 section 5.9.2.5
 615          */
 616         switch (cdb[0]) {
 617         case INQUIRY:
 618         case REPORT_LUNS:
 619                 return 0;
 620         case MAINTENANCE_IN:
 621                 switch (cdb[1] & 0x1f) {
 622                 case MI_REPORT_TARGET_PGS:
 623                         return 0;
 624                 default:
 625                         return TCM_ALUA_STATE_TRANSITION;
 626                 }
 627         case REQUEST_SENSE:
 628         case READ_BUFFER:
 629         case WRITE_BUFFER:
 630                 return 0;
 631         default:
 632                 return TCM_ALUA_STATE_TRANSITION;
 633         }
 634
 635         return 0;
 636 }
 637
 638 /*
 639  * return 1: Is used to signal LUN not accessible, and check condition/not ready
 640  * return 0: Used to signal success
 641  * return -1: Used to signal failure, and invalid cdb field
 642  */
 643 sense_reason_t
 644 target_alua_state_check(struct se_cmd *cmd)
 645 {
 646         struct se_device *dev = cmd->se_dev;
 647         unsigned char *cdb = cmd->t_task_cdb;
 648         struct se_lun *lun = cmd->se_lun;
 649         struct t10_alua_tg_pt_gp *tg_pt_gp;
 650         int out_alua_state, nonop_delay_msecs;
 651         u16 tg_pt_gp_id;
 652         sense_reason_t rc = TCM_NO_SENSE;
 653
 654         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
 655                 return 0;
 656         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
 657                 return 0;
 658
 659         /*
 660          * First, check for a struct se_port specific secondary ALUA target port
 661          * access state: OFFLINE
 662          */
 663         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
 664                 pr_debug("ALUA: Got secondary offline status for local"
 665                                 " target port\n");
 666                 return TCM_ALUA_OFFLINE;
 667         }
 668         rcu_read_lock();
 669         tg_pt_gp = rcu_dereference(lun->lun_tg_pt_gp);
 670         if (!tg_pt_gp) {
 671                 rcu_read_unlock();
 672                 return 0;
 673         }
 674
 675         out_alua_state = tg_pt_gp->tg_pt_gp_alua_access_state;
 676         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 677         tg_pt_gp_id = tg_pt_gp->tg_pt_gp_id;
 678         rcu_read_unlock();
 679         /*
 680          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
 681          * statement so the compiler knows explicitly to check this case first.
 682          * For the Optimized ALUA access state case, we want to process the
 683          * incoming fabric cmd ASAP..
 684          */
 685         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
 686                 return 0;
 687
 688         switch (out_alua_state) {
 689         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 690                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
 691                 break;
 692         case ALUA_ACCESS_STATE_STANDBY:
 693                 rc = core_alua_state_standby(cmd, cdb);
 694                 break;
 695         case ALUA_ACCESS_STATE_UNAVAILABLE:
 696                 rc = core_alua_state_unavailable(cmd, cdb);
 697                 break;
 698         case ALUA_ACCESS_STATE_TRANSITION:
 699                 rc = core_alua_state_transition(cmd, cdb);
 700                 break;
 701         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 702                 rc = core_alua_state_lba_dependent(cmd, tg_pt_gp_id);
 703                 break;
 704         /*
 705          * OFFLINE is a secondary ALUA target port group access state, that is
 706          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
 707          */
 708         case ALUA_ACCESS_STATE_OFFLINE:
 709         default:
 710                 pr_err("Unknown ALUA access state: 0x%02x\n",
 711                                 out_alua_state);
 712                 rc = TCM_INVALID_CDB_FIELD;
 713         }
 714
 715         if (rc && rc != TCM_INVALID_CDB_FIELD) {
 716                 pr_debug("[%s]: ALUA TG Port not available, "
 717                         "SenseKey: NOT_READY, ASC/rc: 0x04/%d\n",
 718                         cmd->se_tfo->fabric_name, rc);
 719         }
 720
 721         return rc;
 722 }
 723
 724 /*
 725  * Check implicit and explicit ALUA state change request.
 726  */
 727 static sense_reason_t
 728 core_alua_check_transition(int state, int valid, int *primary, int explicit)
 729 {
 730         /*
 731          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 732          * defined as primary target port asymmetric access states.
 733          */
 734         switch (state) {
 735         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 736                 if (!(valid & ALUA_AO_SUP))
 737                         goto not_supported;
 738                 *primary = 1;
 739                 break;
 740         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 741                 if (!(valid & ALUA_AN_SUP))
 742                         goto not_supported;
 743                 *primary = 1;
 744                 break;
 745         case ALUA_ACCESS_STATE_STANDBY:
 746                 if (!(valid & ALUA_S_SUP))
 747                         goto not_supported;
 748                 *primary = 1;
 749                 break;
 750         case ALUA_ACCESS_STATE_UNAVAILABLE:
 751                 if (!(valid & ALUA_U_SUP))
 752                         goto not_supported;
 753                 *primary = 1;
 754                 break;
 755         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 756                 if (!(valid & ALUA_LBD_SUP))
 757                         goto not_supported;
 758                 *primary = 1;
 759                 break;
 760         case ALUA_ACCESS_STATE_OFFLINE:
 761                 /*
 762                  * OFFLINE state is defined as a secondary target port
 763                  * asymmetric access state.
 764                  */
 765                 if (!(valid & ALUA_O_SUP))
 766                         goto not_supported;
 767                 *primary = 0;
 768                 break;
 769         case ALUA_ACCESS_STATE_TRANSITION:
 770                 if (!(valid & ALUA_T_SUP) || explicit)
 771                         /*
 772                          * Transitioning is set internally and by tcmu daemon,
 773                          * and cannot be selected through a STPG.
 774                          */
 775                         goto not_supported;
 776                 *primary = 0;
 777                 break;
 778         default:
 779                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 780                 return TCM_INVALID_PARAMETER_LIST;
 781         }
 782
 783         return 0;
 784
 785 not_supported:
 786         pr_err("ALUA access state %s not supported",
 787                core_alua_dump_state(state));
 788         return TCM_INVALID_PARAMETER_LIST;
 789 }
 790
 791 static char *core_alua_dump_state(int state)
 792 {
 793         switch (state) {
 794         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 795                 return "Active/Optimized";
 796         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 797                 return "Active/NonOptimized";
 798         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 799                 return "LBA Dependent";
 800         case ALUA_ACCESS_STATE_STANDBY:
 801                 return "Standby";
 802         case ALUA_ACCESS_STATE_UNAVAILABLE:
 803                 return "Unavailable";
 804         case ALUA_ACCESS_STATE_OFFLINE:
 805                 return "Offline";
 806         case ALUA_ACCESS_STATE_TRANSITION:
 807                 return "Transitioning";
 808         default:
 809                 return "Unknown";
 810         }
 811
 812         return NULL;
 813 }
 814
 815 char *core_alua_dump_status(int status)
 816 {
 817         switch (status) {
 818         case ALUA_STATUS_NONE:
 819                 return "None";
 820         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
 821                 return "Altered by Explicit STPG";
 822         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
 823                 return "Altered by Implicit ALUA";
 824         default:
 825                 return "Unknown";
 826         }
 827
 828         return NULL;
 829 }
 830
 831 /*
 832  * Used by fabric modules to determine when we need to delay processing
 833  * for the Active/NonOptimized paths..
 834  */
 835 int core_alua_check_nonop_delay(
 836         struct se_cmd *cmd)
 837 {
 838         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 839                 return 0;
 840         /*
 841          * The ALUA Active/NonOptimized access state delay can be disabled
 842          * in via configfs with a value of zero
 843          */
 844         if (!cmd->alua_nonop_delay)
 845                 return 0;
 846         /*
 847          * struct se_cmd->alua_nonop_delay gets set by a target port group
 848          * defined interval in core_alua_state_nonoptimized()
 849          */
 850         msleep_interruptible(cmd->alua_nonop_delay);
 851         return 0;
 852 }
 853
 854 static int core_alua_write_tpg_metadata(
 855         const char *path,
 856         unsigned char *md_buf,
 857         u32 md_buf_len)
 858 {
 859         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
 860         loff_t pos = 0;
 861         int ret;
 862
 863         if (IS_ERR(file)) {
 864                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
 865                 return -ENODEV;
 866         }
 867         ret = kernel_write(file, md_buf, md_buf_len, &pos);
 868         if (ret < 0)
 869                 pr_err("Error writing ALUA metadata file: %s\n", path);
 870         fput(file);
 871         return (ret < 0) ? -EIO : 0;
 872 }
 873
 874 static int core_alua_update_tpg_primary_metadata(
 875         struct t10_alua_tg_pt_gp *tg_pt_gp)
 876 {
 877         unsigned char *md_buf;
 878         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
 879         char *path;
 880         int len, rc;
 881
 882         lockdep_assert_held(&tg_pt_gp->tg_pt_gp_transition_mutex);
 883
 884         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
 885         if (!md_buf) {
 886                 pr_err("Unable to allocate buf for ALUA metadata\n");
 887                 return -ENOMEM;
 888         }
 889
 890         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
 891                         "tg_pt_gp_id=%hu\n"
 892                         "alua_access_state=0x%02x\n"
 893                         "alua_access_status=0x%02x\n",
 894                         tg_pt_gp->tg_pt_gp_id,
 895                         tg_pt_gp->tg_pt_gp_alua_access_state,
 896                         tg_pt_gp->tg_pt_gp_alua_access_status);
 897
 898         rc = -ENOMEM;
 899         path = kasprintf(GFP_KERNEL, "%s/alua/tpgs_%s/%s", db_root,
 900                         &wwn->unit_serial[0],
 901                         config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 902         if (path) {
 903                 rc = core_alua_write_tpg_metadata(path, md_buf, len);
 904                 kfree(path);
 905         }
 906         kfree(md_buf);
 907         return rc;
 908 }
 909
 910 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
 911 {
 912         struct se_dev_entry *se_deve;
 913         struct se_lun *lun;
 914         struct se_lun_acl *lacl;
 915
 916         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 917         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 918                                 lun_tg_pt_gp_link) {
 919                 /*
 920                  * After an implicit target port asymmetric access state
 921                  * change, a device server shall establish a unit attention
 922                  * condition for the initiator port associated with every I_T
 923                  * nexus with the additional sense code set to ASYMMETRIC
 924                  * ACCESS STATE CHANGED.
 925                  *
 926                  * After an explicit target port asymmetric access state
 927                  * change, a device server shall establish a unit attention
 928                  * condition with the additional sense code set to ASYMMETRIC
 929                  * ACCESS STATE CHANGED for the initiator port associated with
 930                  * every I_T nexus other than the I_T nexus on which the SET
 931                  * TARGET PORT GROUPS command
 932                  */
 933                 if (!percpu_ref_tryget_live(&lun->lun_ref))
 934                         continue;
 935                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 936
 937                 spin_lock(&lun->lun_deve_lock);
 938                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
 939                         lacl = se_deve->se_lun_acl;
 940
 941                         /*
 942                          * spc4r37 p.242:
 943                          * After an explicit target port asymmetric access
 944                          * state change, a device server shall establish a
 945                          * unit attention condition with the additional sense
 946                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
 947                          * the initiator port associated with every I_T nexus
 948                          * other than the I_T nexus on which the SET TARGET
 949                          * PORT GROUPS command was received.
 950                          */
 951                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
 952                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
 953                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
 954                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
 955                                 continue;
 956
 957                         /*
 958                          * se_deve->se_lun_acl pointer may be NULL for a
 959                          * entry created without explicit Node+MappedLUN ACLs
 960                          */
 961                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
 962                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
 963                                 continue;
 964
 965                         core_scsi3_ua_allocate(se_deve, 0x2A,
 966                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
 967                 }
 968                 spin_unlock(&lun->lun_deve_lock);
 969
 970                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 971                 percpu_ref_put(&lun->lun_ref);
 972         }
 973         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 974 }
 975
 976 static int core_alua_do_transition_tg_pt(
 977         struct t10_alua_tg_pt_gp *tg_pt_gp,
 978         int new_state,
 979         int explicit)
 980 {
 981         int prev_state;
 982
 983         mutex_lock(&tg_pt_gp->tg_pt_gp_transition_mutex);
 984         /* Nothing to be done here */
 985         if (tg_pt_gp->tg_pt_gp_alua_access_state == new_state) {
 986                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
 987                 return 0;
 988         }
 989
 990         if (explicit && new_state == ALUA_ACCESS_STATE_TRANSITION) {
 991                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
 992                 return -EAGAIN;
 993         }
 994
 995         /*
 996          * Save the old primary ALUA access state, and set the current state
 997          * to ALUA_ACCESS_STATE_TRANSITION.
 998          */
 999         prev_state = tg_pt_gp->tg_pt_gp_alua_access_state;
1000         tg_pt_gp->tg_pt_gp_alua_access_state = ALUA_ACCESS_STATE_TRANSITION;
1001         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1002                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1003                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1004
1005         core_alua_queue_state_change_ua(tg_pt_gp);
1006
1007         if (new_state == ALUA_ACCESS_STATE_TRANSITION) {
1008                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1009                 return 0;
1010         }
1011
1012         /*
1013          * Check for the optional ALUA primary state transition delay
1014          */
1015         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1016                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1017
1018         /*
1019          * Set the current primary ALUA access state to the requested new state
1020          */
1021         tg_pt_gp->tg_pt_gp_alua_access_state = new_state;
1022
1023         /*
1024          * Update the ALUA metadata buf that has been allocated in
1025          * core_alua_do_port_transition(), this metadata will be written
1026          * to struct file.
1027          *
1028          * Note that there is the case where we do not want to update the
1029          * metadata when the saved metadata is being parsed in userspace
1030          * when setting the existing port access state and access status.
1031          *
1032          * Also note that the failure to write out the ALUA metadata to
1033          * struct file does NOT affect the actual ALUA transition.
1034          */
1035         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1036                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1037         }
1038
1039         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1040                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1041                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1042                 tg_pt_gp->tg_pt_gp_id,
1043                 core_alua_dump_state(prev_state),
1044                 core_alua_dump_state(new_state));
1045
1046         core_alua_queue_state_change_ua(tg_pt_gp);
1047
1048         mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1049         return 0;
1050 }
1051
1052 int core_alua_do_port_transition(
1053         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1054         struct se_device *l_dev,
1055         struct se_lun *l_lun,
1056         struct se_node_acl *l_nacl,
1057         int new_state,
1058         int explicit)
1059 {
1060         struct se_device *dev;
1061         struct t10_alua_lu_gp *lu_gp;
1062         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1063         struct t10_alua_tg_pt_gp *tg_pt_gp;
1064         int primary, valid_states, rc = 0;
1065
1066         if (l_dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
1067                 return -ENODEV;
1068
1069         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1070         if (core_alua_check_transition(new_state, valid_states, &primary,
1071                                        explicit) != 0)
1072                 return -EINVAL;
1073
1074         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1075         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1076         lu_gp = local_lu_gp_mem->lu_gp;
1077         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1078         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1079         /*
1080          * For storage objects that are members of the 'default_lu_gp',
1081          * we only do transition on the passed *l_tp_pt_gp, and not
1082          * on all of the matching target port groups IDs in default_lu_gp.
1083          */
1084         if (!lu_gp->lu_gp_id) {
1085                 /*
1086                  * core_alua_do_transition_tg_pt() will always return
1087                  * success.
1088                  */
1089                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1090                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1091                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1092                                                    new_state, explicit);
1093                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1094                 return rc;
1095         }
1096         /*
1097          * For all other LU groups aside from 'default_lu_gp', walk all of
1098          * the associated storage objects looking for a matching target port
1099          * group ID from the local target port group.
1100          */
1101         spin_lock(&lu_gp->lu_gp_lock);
1102         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1103                                 lu_gp_mem_list) {
1104
1105                 dev = lu_gp_mem->lu_gp_mem_dev;
1106                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1107                 spin_unlock(&lu_gp->lu_gp_lock);
1108
1109                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1110                 list_for_each_entry(tg_pt_gp,
1111                                 &dev->t10_alua.tg_pt_gps_list,
1112                                 tg_pt_gp_list) {
1113
1114                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1115                                 continue;
1116                         /*
1117                          * If the target behavior port asymmetric access state
1118                          * is changed for any target port group accessible via
1119                          * a logical unit within a LU group, the target port
1120                          * behavior group asymmetric access states for the same
1121                          * target port group accessible via other logical units
1122                          * in that LU group will also change.
1123                          */
1124                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1125                                 continue;
1126
1127                         if (l_tg_pt_gp == tg_pt_gp) {
1128                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1129                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1130                         } else {
1131                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1132                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1133                         }
1134                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1135                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1136                         /*
1137                          * core_alua_do_transition_tg_pt() will always return
1138                          * success.
1139                          */
1140                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1141                                         new_state, explicit);
1142
1143                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1144                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1145                         if (rc)
1146                                 break;
1147                 }
1148                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1149
1150                 spin_lock(&lu_gp->lu_gp_lock);
1151                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1152         }
1153         spin_unlock(&lu_gp->lu_gp_lock);
1154
1155         if (!rc) {
1156                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1157                          " Group IDs: %hu %s transition to primary state: %s\n",
1158                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1159                          l_tg_pt_gp->tg_pt_gp_id,
1160                          (explicit) ? "explicit" : "implicit",
1161                          core_alua_dump_state(new_state));
1162         }
1163
1164         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1165         return rc;
1166 }
1167
1168 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1169 {
1170         struct se_portal_group *se_tpg = lun->lun_tpg;
1171         unsigned char *md_buf;
1172         char *path;
1173         int len, rc;
1174
1175         mutex_lock(&lun->lun_tg_pt_md_mutex);
1176
1177         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1178         if (!md_buf) {
1179                 pr_err("Unable to allocate buf for ALUA metadata\n");
1180                 rc = -ENOMEM;
1181                 goto out_unlock;
1182         }
1183
1184         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1185                         "alua_tg_pt_status=0x%02x\n",
1186                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1187                         lun->lun_tg_pt_secondary_stat);
1188
1189         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) {
1190                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s+%hu/lun_%llu",
1191                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1192                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1193                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
1194                                 lun->unpacked_lun);
1195         } else {
1196                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s/lun_%llu",
1197                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1198                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1199                                 lun->unpacked_lun);
1200         }
1201         if (!path) {
1202                 rc = -ENOMEM;
1203                 goto out_free;
1204         }
1205
1206         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1207         kfree(path);
1208 out_free:
1209         kfree(md_buf);
1210 out_unlock:
1211         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1212         return rc;
1213 }
1214
1215 static int core_alua_set_tg_pt_secondary_state(
1216         struct se_lun *lun,
1217         int explicit,
1218         int offline)
1219 {
1220         struct t10_alua_tg_pt_gp *tg_pt_gp;
1221         int trans_delay_msecs;
1222
1223         rcu_read_lock();
1224         tg_pt_gp = rcu_dereference(lun->lun_tg_pt_gp);
1225         if (!tg_pt_gp) {
1226                 rcu_read_unlock();
1227                 pr_err("Unable to complete secondary state"
1228                                 " transition\n");
1229                 return -EINVAL;
1230         }
1231         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1232         /*
1233          * Set the secondary ALUA target port access state to OFFLINE
1234          * or release the previously secondary state for struct se_lun
1235          */
1236         if (offline)
1237                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1238         else
1239                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1240
1241         lun->lun_tg_pt_secondary_stat = (explicit) ?
1242                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1243                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1244
1245         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1246                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1247                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1248                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1249
1250         rcu_read_unlock();
1251         /*
1252          * Do the optional transition delay after we set the secondary
1253          * ALUA access state.
1254          */
1255         if (trans_delay_msecs != 0)
1256                 msleep_interruptible(trans_delay_msecs);
1257         /*
1258          * See if we need to update the ALUA fabric port metadata for
1259          * secondary state and status
1260          */
1261         if (lun->lun_tg_pt_secondary_write_md)
1262                 core_alua_update_tpg_secondary_metadata(lun);
1263
1264         return 0;
1265 }
1266
1267 struct t10_alua_lba_map *
1268 core_alua_allocate_lba_map(struct list_head *list,
1269                            u64 first_lba, u64 last_lba)
1270 {
1271         struct t10_alua_lba_map *lba_map;
1272
1273         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1274         if (!lba_map) {
1275                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1276                 return ERR_PTR(-ENOMEM);
1277         }
1278         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1279         lba_map->lba_map_first_lba = first_lba;
1280         lba_map->lba_map_last_lba = last_lba;
1281
1282         list_add_tail(&lba_map->lba_map_list, list);
1283         return lba_map;
1284 }
1285
1286 int
1287 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1288                                int pg_id, int state)
1289 {
1290         struct t10_alua_lba_map_member *lba_map_mem;
1291
1292         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1293                             lba_map_mem_list) {
1294                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1295                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1296                         return -EINVAL;
1297                 }
1298         }
1299
1300         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1301         if (!lba_map_mem) {
1302                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1303                 return -ENOMEM;
1304         }
1305         lba_map_mem->lba_map_mem_alua_state = state;
1306         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1307
1308         list_add_tail(&lba_map_mem->lba_map_mem_list,
1309                       &lba_map->lba_map_mem_list);
1310         return 0;
1311 }
1312
1313 void
1314 core_alua_free_lba_map(struct list_head *lba_list)
1315 {
1316         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1317         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1318
1319         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1320                                  lba_map_list) {
1321                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1322                                          &lba_map->lba_map_mem_list,
1323                                          lba_map_mem_list) {
1324                         list_del(&lba_map_mem->lba_map_mem_list);
1325                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1326                                         lba_map_mem);
1327                 }
1328                 list_del(&lba_map->lba_map_list);
1329                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1330         }
1331 }
1332
1333 void
1334 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1335                       int segment_size, int segment_mult)
1336 {
1337         struct list_head old_lba_map_list;
1338         struct t10_alua_tg_pt_gp *tg_pt_gp;
1339         int activate = 0, supported;
1340
1341         INIT_LIST_HEAD(&old_lba_map_list);
1342         spin_lock(&dev->t10_alua.lba_map_lock);
1343         dev->t10_alua.lba_map_segment_size = segment_size;
1344         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1345         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1346         if (lba_map_list) {
1347                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1348                 activate = 1;
1349         }
1350         spin_unlock(&dev->t10_alua.lba_map_lock);
1351         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1352         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1353                             tg_pt_gp_list) {
1354
1355                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1356                         continue;
1357                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1358                 if (activate)
1359                         supported |= ALUA_LBD_SUP;
1360                 else
1361                         supported &= ~ALUA_LBD_SUP;
1362                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1363         }
1364         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1365         core_alua_free_lba_map(&old_lba_map_list);
1366 }
1367
1368 struct t10_alua_lu_gp *
1369 core_alua_allocate_lu_gp(const char *name, int def_group)
1370 {
1371         struct t10_alua_lu_gp *lu_gp;
1372
1373         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1374         if (!lu_gp) {
1375                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1376                 return ERR_PTR(-ENOMEM);
1377         }
1378         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1379         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1380         spin_lock_init(&lu_gp->lu_gp_lock);
1381         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1382
1383         if (def_group) {
1384                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1385                 lu_gp->lu_gp_valid_id = 1;
1386                 alua_lu_gps_count++;
1387         }
1388
1389         return lu_gp;
1390 }
1391
1392 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1393 {
1394         struct t10_alua_lu_gp *lu_gp_tmp;
1395         u16 lu_gp_id_tmp;
1396         /*
1397          * The lu_gp->lu_gp_id may only be set once..
1398          */
1399         if (lu_gp->lu_gp_valid_id) {
1400                 pr_warn("ALUA LU Group already has a valid ID,"
1401                         " ignoring request\n");
1402                 return -EINVAL;
1403         }
1404
1405         spin_lock(&lu_gps_lock);
1406         if (alua_lu_gps_count == 0x0000ffff) {
1407                 pr_err("Maximum ALUA alua_lu_gps_count:"
1408                                 " 0x0000ffff reached\n");
1409                 spin_unlock(&lu_gps_lock);
1410                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1411                 return -ENOSPC;
1412         }
1413 again:
1414         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1415                                 alua_lu_gps_counter++;
1416
1417         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1418                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1419                         if (!lu_gp_id)
1420                                 goto again;
1421
1422                         pr_warn("ALUA Logical Unit Group ID: %hu"
1423                                 " already exists, ignoring request\n",
1424                                 lu_gp_id);
1425                         spin_unlock(&lu_gps_lock);
1426                         return -EINVAL;
1427                 }
1428         }
1429
1430         lu_gp->lu_gp_id = lu_gp_id_tmp;
1431         lu_gp->lu_gp_valid_id = 1;
1432         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1433         alua_lu_gps_count++;
1434         spin_unlock(&lu_gps_lock);
1435
1436         return 0;
1437 }
1438
1439 static struct t10_alua_lu_gp_member *
1440 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1441 {
1442         struct t10_alua_lu_gp_member *lu_gp_mem;
1443
1444         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1445         if (!lu_gp_mem) {
1446                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1447                 return ERR_PTR(-ENOMEM);
1448         }
1449         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1450         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1451         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1452
1453         lu_gp_mem->lu_gp_mem_dev = dev;
1454         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1455
1456         return lu_gp_mem;
1457 }
1458
1459 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1460 {
1461         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1462         /*
1463          * Once we have reached this point, config_item_put() has
1464          * already been called from target_core_alua_drop_lu_gp().
1465          *
1466          * Here, we remove the *lu_gp from the global list so that
1467          * no associations can be made while we are releasing
1468          * struct t10_alua_lu_gp.
1469          */
1470         spin_lock(&lu_gps_lock);
1471         list_del(&lu_gp->lu_gp_node);
1472         alua_lu_gps_count--;
1473         spin_unlock(&lu_gps_lock);
1474         /*
1475          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1476          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1477          * released with core_alua_put_lu_gp_from_name()
1478          */
1479         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1480                 cpu_relax();
1481         /*
1482          * Release reference to struct t10_alua_lu_gp * from all associated
1483          * struct se_device.
1484          */
1485         spin_lock(&lu_gp->lu_gp_lock);
1486         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1487                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1488                 if (lu_gp_mem->lu_gp_assoc) {
1489                         list_del(&lu_gp_mem->lu_gp_mem_list);
1490                         lu_gp->lu_gp_members--;
1491                         lu_gp_mem->lu_gp_assoc = 0;
1492                 }
1493                 spin_unlock(&lu_gp->lu_gp_lock);
1494                 /*
1495                  *
1496                  * lu_gp_mem is associated with a single
1497                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1498                  * struct se_device is released via core_alua_free_lu_gp_mem().
1499                  *
1500                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1501                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1502                  */
1503                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1504                 if (lu_gp != default_lu_gp)
1505                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1506                                         default_lu_gp);
1507                 else
1508                         lu_gp_mem->lu_gp = NULL;
1509                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1510
1511                 spin_lock(&lu_gp->lu_gp_lock);
1512         }
1513         spin_unlock(&lu_gp->lu_gp_lock);
1514
1515         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1516 }
1517
1518 void core_alua_free_lu_gp_mem(struct se_device *dev)
1519 {
1520         struct t10_alua_lu_gp *lu_gp;
1521         struct t10_alua_lu_gp_member *lu_gp_mem;
1522
1523         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1524         if (!lu_gp_mem)
1525                 return;
1526
1527         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1528                 cpu_relax();
1529
1530         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1531         lu_gp = lu_gp_mem->lu_gp;
1532         if (lu_gp) {
1533                 spin_lock(&lu_gp->lu_gp_lock);
1534                 if (lu_gp_mem->lu_gp_assoc) {
1535                         list_del(&lu_gp_mem->lu_gp_mem_list);
1536                         lu_gp->lu_gp_members--;
1537                         lu_gp_mem->lu_gp_assoc = 0;
1538                 }
1539                 spin_unlock(&lu_gp->lu_gp_lock);
1540                 lu_gp_mem->lu_gp = NULL;
1541         }
1542         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1543
1544         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1545 }
1546
1547 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1548 {
1549         struct t10_alua_lu_gp *lu_gp;
1550         struct config_item *ci;
1551
1552         spin_lock(&lu_gps_lock);
1553         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1554                 if (!lu_gp->lu_gp_valid_id)
1555                         continue;
1556                 ci = &lu_gp->lu_gp_group.cg_item;
1557                 if (!strcmp(config_item_name(ci), name)) {
1558                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1559                         spin_unlock(&lu_gps_lock);
1560                         return lu_gp;
1561                 }
1562         }
1563         spin_unlock(&lu_gps_lock);
1564
1565         return NULL;
1566 }
1567
1568 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1569 {
1570         spin_lock(&lu_gps_lock);
1571         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1572         spin_unlock(&lu_gps_lock);
1573 }
1574
1575 /*
1576  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1577  */
1578 void __core_alua_attach_lu_gp_mem(
1579         struct t10_alua_lu_gp_member *lu_gp_mem,
1580         struct t10_alua_lu_gp *lu_gp)
1581 {
1582         spin_lock(&lu_gp->lu_gp_lock);
1583         lu_gp_mem->lu_gp = lu_gp;
1584         lu_gp_mem->lu_gp_assoc = 1;
1585         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1586         lu_gp->lu_gp_members++;
1587         spin_unlock(&lu_gp->lu_gp_lock);
1588 }
1589
1590 /*
1591  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1592  */
1593 void __core_alua_drop_lu_gp_mem(
1594         struct t10_alua_lu_gp_member *lu_gp_mem,
1595         struct t10_alua_lu_gp *lu_gp)
1596 {
1597         spin_lock(&lu_gp->lu_gp_lock);
1598         list_del(&lu_gp_mem->lu_gp_mem_list);
1599         lu_gp_mem->lu_gp = NULL;
1600         lu_gp_mem->lu_gp_assoc = 0;
1601         lu_gp->lu_gp_members--;
1602         spin_unlock(&lu_gp->lu_gp_lock);
1603 }
1604
1605 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1606                 const char *name, int def_group)
1607 {
1608         struct t10_alua_tg_pt_gp *tg_pt_gp;
1609
1610         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1611         if (!tg_pt_gp) {
1612                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1613                 return NULL;
1614         }
1615         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1616         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1617         mutex_init(&tg_pt_gp->tg_pt_gp_transition_mutex);
1618         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1619         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1620         tg_pt_gp->tg_pt_gp_dev = dev;
1621         tg_pt_gp->tg_pt_gp_alua_access_state =
1622                         ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED;
1623         /*
1624          * Enable both explicit and implicit ALUA support by default
1625          */
1626         tg_pt_gp->tg_pt_gp_alua_access_type =
1627                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1628         /*
1629          * Set the default Active/NonOptimized Delay in milliseconds
1630          */
1631         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1632         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1633         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1634
1635         /*
1636          * Enable all supported states
1637          */
1638         tg_pt_gp->tg_pt_gp_alua_supported_states =
1639             ALUA_T_SUP | ALUA_O_SUP |
1640             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1641
1642         if (def_group) {
1643                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1644                 tg_pt_gp->tg_pt_gp_id =
1645                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1646                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1647                 dev->t10_alua.alua_tg_pt_gps_count++;
1648                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1649                               &dev->t10_alua.tg_pt_gps_list);
1650                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1651         }
1652
1653         return tg_pt_gp;
1654 }
1655
1656 int core_alua_set_tg_pt_gp_id(
1657         struct t10_alua_tg_pt_gp *tg_pt_gp,
1658         u16 tg_pt_gp_id)
1659 {
1660         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1661         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1662         u16 tg_pt_gp_id_tmp;
1663
1664         /*
1665          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1666          */
1667         if (tg_pt_gp->tg_pt_gp_valid_id) {
1668                 pr_warn("ALUA TG PT Group already has a valid ID,"
1669                         " ignoring request\n");
1670                 return -EINVAL;
1671         }
1672
1673         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1674         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1675                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1676                         " 0x0000ffff reached\n");
1677                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1678                 return -ENOSPC;
1679         }
1680 again:
1681         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1682                         dev->t10_alua.alua_tg_pt_gps_counter++;
1683
1684         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1685                         tg_pt_gp_list) {
1686                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1687                         if (!tg_pt_gp_id)
1688                                 goto again;
1689
1690                         pr_err("ALUA Target Port Group ID: %hu already"
1691                                 " exists, ignoring request\n", tg_pt_gp_id);
1692                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1693                         return -EINVAL;
1694                 }
1695         }
1696
1697         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1698         tg_pt_gp->tg_pt_gp_valid_id = 1;
1699         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1700                         &dev->t10_alua.tg_pt_gps_list);
1701         dev->t10_alua.alua_tg_pt_gps_count++;
1702         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1703
1704         return 0;
1705 }
1706
1707 void core_alua_free_tg_pt_gp(
1708         struct t10_alua_tg_pt_gp *tg_pt_gp)
1709 {
1710         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1711         struct se_lun *lun, *next;
1712
1713         /*
1714          * Once we have reached this point, config_item_put() has already
1715          * been called from target_core_alua_drop_tg_pt_gp().
1716          *
1717          * Here we remove *tg_pt_gp from the global list so that
1718          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1719          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1720          */
1721         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1722         if (tg_pt_gp->tg_pt_gp_valid_id) {
1723                 list_del(&tg_pt_gp->tg_pt_gp_list);
1724                 dev->t10_alua.alua_tg_pt_gps_count--;
1725         }
1726         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1727
1728         /*
1729          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1730          * core_alua_get_tg_pt_gp_by_name() in
1731          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1732          * to be released with core_alua_put_tg_pt_gp_from_name().
1733          */
1734         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1735                 cpu_relax();
1736
1737         /*
1738          * Release reference to struct t10_alua_tg_pt_gp from all associated
1739          * struct se_port.
1740          */
1741         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1742         list_for_each_entry_safe(lun, next,
1743                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1744                 list_del_init(&lun->lun_tg_pt_gp_link);
1745                 tg_pt_gp->tg_pt_gp_members--;
1746
1747                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1748                 /*
1749                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1750                  * assume we want to re-associate a given tg_pt_gp_mem with
1751                  * default_tg_pt_gp.
1752                  */
1753                 spin_lock(&lun->lun_tg_pt_gp_lock);
1754                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1755                         __target_attach_tg_pt_gp(lun,
1756                                         dev->t10_alua.default_tg_pt_gp);
1757                 } else
1758                         rcu_assign_pointer(lun->lun_tg_pt_gp, NULL);
1759                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1760
1761                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1762         }
1763         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1764
1765         synchronize_rcu();
1766         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1767 }
1768
1769 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1770                 struct se_device *dev, const char *name)
1771 {
1772         struct t10_alua_tg_pt_gp *tg_pt_gp;
1773         struct config_item *ci;
1774
1775         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1776         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1777                         tg_pt_gp_list) {
1778                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1779                         continue;
1780                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1781                 if (!strcmp(config_item_name(ci), name)) {
1782                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1783                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1784                         return tg_pt_gp;
1785                 }
1786         }
1787         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1788
1789         return NULL;
1790 }
1791
1792 static void core_alua_put_tg_pt_gp_from_name(
1793         struct t10_alua_tg_pt_gp *tg_pt_gp)
1794 {
1795         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1796
1797         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1798         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1799         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1800 }
1801
1802 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1803                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1804 {
1805         struct se_dev_entry *se_deve;
1806
1807         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1808
1809         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1810         rcu_assign_pointer(lun->lun_tg_pt_gp, tg_pt_gp);
1811         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1812         tg_pt_gp->tg_pt_gp_members++;
1813         spin_lock(&lun->lun_deve_lock);
1814         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1815                 core_scsi3_ua_allocate(se_deve, 0x3f,
1816                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1817         spin_unlock(&lun->lun_deve_lock);
1818         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1819 }
1820
1821 void target_attach_tg_pt_gp(struct se_lun *lun,
1822                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1823 {
1824         spin_lock(&lun->lun_tg_pt_gp_lock);
1825         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1826         spin_unlock(&lun->lun_tg_pt_gp_lock);
1827         synchronize_rcu();
1828 }
1829
1830 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1831                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1832 {
1833         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1834
1835         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1836         list_del_init(&lun->lun_tg_pt_gp_link);
1837         tg_pt_gp->tg_pt_gp_members--;
1838         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1839 }
1840
1841 void target_detach_tg_pt_gp(struct se_lun *lun)
1842 {
1843         struct t10_alua_tg_pt_gp *tg_pt_gp;
1844
1845         spin_lock(&lun->lun_tg_pt_gp_lock);
1846         tg_pt_gp = rcu_dereference_check(lun->lun_tg_pt_gp,
1847                                 lockdep_is_held(&lun->lun_tg_pt_gp_lock));
1848         if (tg_pt_gp) {
1849                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1850                 rcu_assign_pointer(lun->lun_tg_pt_gp, NULL);
1851         }
1852         spin_unlock(&lun->lun_tg_pt_gp_lock);
1853         synchronize_rcu();
1854 }
1855
1856 static void target_swap_tg_pt_gp(struct se_lun *lun,
1857                                  struct t10_alua_tg_pt_gp *old_tg_pt_gp,
1858                                  struct t10_alua_tg_pt_gp *new_tg_pt_gp)
1859 {
1860         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1861
1862         if (old_tg_pt_gp)
1863                 __target_detach_tg_pt_gp(lun, old_tg_pt_gp);
1864         __target_attach_tg_pt_gp(lun, new_tg_pt_gp);
1865 }
1866
1867 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1868 {
1869         struct config_item *tg_pt_ci;
1870         struct t10_alua_tg_pt_gp *tg_pt_gp;
1871         ssize_t len = 0;
1872
1873         rcu_read_lock();
1874         tg_pt_gp = rcu_dereference(lun->lun_tg_pt_gp);
1875         if (tg_pt_gp) {
1876                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1877                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1878                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1879                         "Primary Access Status: %s\nTG Port Secondary Access"
1880                         " State: %s\nTG Port Secondary Access Status: %s\n",
1881                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1882                         core_alua_dump_state(
1883                                 tg_pt_gp->tg_pt_gp_alua_access_state),
1884                         core_alua_dump_status(
1885                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1886                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1887                         "Offline" : "None",
1888                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1889         }
1890         rcu_read_unlock();
1891
1892         return len;
1893 }
1894
1895 ssize_t core_alua_store_tg_pt_gp_info(
1896         struct se_lun *lun,
1897         const char *page,
1898         size_t count)
1899 {
1900         struct se_portal_group *tpg = lun->lun_tpg;
1901         /*
1902          * rcu_dereference_raw protected by se_lun->lun_group symlink
1903          * reference to se_device->dev_group.
1904          */
1905         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1906         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1907         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1908         int move = 0;
1909
1910         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1911             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1912                 return -ENODEV;
1913
1914         if (count > TG_PT_GROUP_NAME_BUF) {
1915                 pr_err("ALUA Target Port Group alias too large!\n");
1916                 return -EINVAL;
1917         }
1918         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1919         memcpy(buf, page, count);
1920         /*
1921          * Any ALUA target port group alias besides "NULL" means we will be
1922          * making a new group association.
1923          */
1924         if (strcmp(strstrip(buf), "NULL")) {
1925                 /*
1926                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1927                  * struct t10_alua_tg_pt_gp.  This reference is released with
1928                  * core_alua_put_tg_pt_gp_from_name() below.
1929                  */
1930                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1931                                         strstrip(buf));
1932                 if (!tg_pt_gp_new)
1933                         return -ENODEV;
1934         }
1935
1936         spin_lock(&lun->lun_tg_pt_gp_lock);
1937         tg_pt_gp = rcu_dereference_check(lun->lun_tg_pt_gp,
1938                                 lockdep_is_held(&lun->lun_tg_pt_gp_lock));
1939         if (tg_pt_gp) {
1940                 /*
1941                  * Clearing an existing tg_pt_gp association, and replacing
1942                  * with the default_tg_pt_gp.
1943                  */
1944                 if (!tg_pt_gp_new) {
1945                         pr_debug("Target_Core_ConfigFS: Moving"
1946                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1947                                 " alua/%s, ID: %hu back to"
1948                                 " default_tg_pt_gp\n",
1949                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1950                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1951                                 config_item_name(&lun->lun_group.cg_item),
1952                                 config_item_name(
1953                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1954                                 tg_pt_gp->tg_pt_gp_id);
1955
1956                         target_swap_tg_pt_gp(lun, tg_pt_gp,
1957                                         dev->t10_alua.default_tg_pt_gp);
1958                         spin_unlock(&lun->lun_tg_pt_gp_lock);
1959
1960                         goto sync_rcu;
1961                 }
1962                 move = 1;
1963         }
1964
1965         target_swap_tg_pt_gp(lun, tg_pt_gp, tg_pt_gp_new);
1966         spin_unlock(&lun->lun_tg_pt_gp_lock);
1967         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1968                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1969                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1970                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1971                 config_item_name(&lun->lun_group.cg_item),
1972                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1973                 tg_pt_gp_new->tg_pt_gp_id);
1974
1975         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1976 sync_rcu:
1977         synchronize_rcu();
1978         return count;
1979 }
1980
1981 ssize_t core_alua_show_access_type(
1982         struct t10_alua_tg_pt_gp *tg_pt_gp,
1983         char *page)
1984 {
1985         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
1986             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
1987                 return sprintf(page, "Implicit and Explicit\n");
1988         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
1989                 return sprintf(page, "Implicit\n");
1990         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
1991                 return sprintf(page, "Explicit\n");
1992         else
1993                 return sprintf(page, "None\n");
1994 }
1995
1996 ssize_t core_alua_store_access_type(
1997         struct t10_alua_tg_pt_gp *tg_pt_gp,
1998         const char *page,
1999         size_t count)
2000 {
2001         unsigned long tmp;
2002         int ret;
2003
2004         ret = kstrtoul(page, 0, &tmp);
2005         if (ret < 0) {
2006                 pr_err("Unable to extract alua_access_type\n");
2007                 return ret;
2008         }
2009         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2010                 pr_err("Illegal value for alua_access_type:"
2011                                 " %lu\n", tmp);
2012                 return -EINVAL;
2013         }
2014         if (tmp == 3)
2015                 tg_pt_gp->tg_pt_gp_alua_access_type =
2016                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2017         else if (tmp == 2)
2018                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2019         else if (tmp == 1)
2020                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2021         else
2022                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2023
2024         return count;
2025 }
2026
2027 ssize_t core_alua_show_nonop_delay_msecs(
2028         struct t10_alua_tg_pt_gp *tg_pt_gp,
2029         char *page)
2030 {
2031         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2032 }
2033
2034 ssize_t core_alua_store_nonop_delay_msecs(
2035         struct t10_alua_tg_pt_gp *tg_pt_gp,
2036         const char *page,
2037         size_t count)
2038 {
2039         unsigned long tmp;
2040         int ret;
2041
2042         ret = kstrtoul(page, 0, &tmp);
2043         if (ret < 0) {
2044                 pr_err("Unable to extract nonop_delay_msecs\n");
2045                 return ret;
2046         }
2047         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2048                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2049                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2050                         ALUA_MAX_NONOP_DELAY_MSECS);
2051                 return -EINVAL;
2052         }
2053         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2054
2055         return count;
2056 }
2057
2058 ssize_t core_alua_show_trans_delay_msecs(
2059         struct t10_alua_tg_pt_gp *tg_pt_gp,
2060         char *page)
2061 {
2062         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2063 }
2064
2065 ssize_t core_alua_store_trans_delay_msecs(
2066         struct t10_alua_tg_pt_gp *tg_pt_gp,
2067         const char *page,
2068         size_t count)
2069 {
2070         unsigned long tmp;
2071         int ret;
2072
2073         ret = kstrtoul(page, 0, &tmp);
2074         if (ret < 0) {
2075                 pr_err("Unable to extract trans_delay_msecs\n");
2076                 return ret;
2077         }
2078         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2079                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2080                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2081                         ALUA_MAX_TRANS_DELAY_MSECS);
2082                 return -EINVAL;
2083         }
2084         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2085
2086         return count;
2087 }
2088
2089 ssize_t core_alua_show_implicit_trans_secs(
2090         struct t10_alua_tg_pt_gp *tg_pt_gp,
2091         char *page)
2092 {
2093         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2094 }
2095
2096 ssize_t core_alua_store_implicit_trans_secs(
2097         struct t10_alua_tg_pt_gp *tg_pt_gp,
2098         const char *page,
2099         size_t count)
2100 {
2101         unsigned long tmp;
2102         int ret;
2103
2104         ret = kstrtoul(page, 0, &tmp);
2105         if (ret < 0) {
2106                 pr_err("Unable to extract implicit_trans_secs\n");
2107                 return ret;
2108         }
2109         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2110                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2111                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2112                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2113                 return  -EINVAL;
2114         }
2115         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2116
2117         return count;
2118 }
2119
2120 ssize_t core_alua_show_preferred_bit(
2121         struct t10_alua_tg_pt_gp *tg_pt_gp,
2122         char *page)
2123 {
2124         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2125 }
2126
2127 ssize_t core_alua_store_preferred_bit(
2128         struct t10_alua_tg_pt_gp *tg_pt_gp,
2129         const char *page,
2130         size_t count)
2131 {
2132         unsigned long tmp;
2133         int ret;
2134
2135         ret = kstrtoul(page, 0, &tmp);
2136         if (ret < 0) {
2137                 pr_err("Unable to extract preferred ALUA value\n");
2138                 return ret;
2139         }
2140         if ((tmp != 0) && (tmp != 1)) {
2141                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2142                 return -EINVAL;
2143         }
2144         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2145
2146         return count;
2147 }
2148
2149 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2150 {
2151         return sprintf(page, "%d\n",
2152                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2153 }
2154
2155 ssize_t core_alua_store_offline_bit(
2156         struct se_lun *lun,
2157         const char *page,
2158         size_t count)
2159 {
2160         /*
2161          * rcu_dereference_raw protected by se_lun->lun_group symlink
2162          * reference to se_device->dev_group.
2163          */
2164         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2165         unsigned long tmp;
2166         int ret;
2167
2168         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2169             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2170                 return -ENODEV;
2171
2172         ret = kstrtoul(page, 0, &tmp);
2173         if (ret < 0) {
2174                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2175                 return ret;
2176         }
2177         if ((tmp != 0) && (tmp != 1)) {
2178                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2179                                 tmp);
2180                 return -EINVAL;
2181         }
2182
2183         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2184         if (ret < 0)
2185                 return -EINVAL;
2186
2187         return count;
2188 }
2189
2190 ssize_t core_alua_show_secondary_status(
2191         struct se_lun *lun,
2192         char *page)
2193 {
2194         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2195 }
2196
2197 ssize_t core_alua_store_secondary_status(
2198         struct se_lun *lun,
2199         const char *page,
2200         size_t count)
2201 {
2202         unsigned long tmp;
2203         int ret;
2204
2205         ret = kstrtoul(page, 0, &tmp);
2206         if (ret < 0) {
2207                 pr_err("Unable to extract alua_tg_pt_status\n");
2208                 return ret;
2209         }
2210         if ((tmp != ALUA_STATUS_NONE) &&
2211             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2212             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2213                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2214                                 tmp);
2215                 return -EINVAL;
2216         }
2217         lun->lun_tg_pt_secondary_stat = (int)tmp;
2218
2219         return count;
2220 }
2221
2222 ssize_t core_alua_show_secondary_write_metadata(
2223         struct se_lun *lun,
2224         char *page)
2225 {
2226         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2227 }
2228
2229 ssize_t core_alua_store_secondary_write_metadata(
2230         struct se_lun *lun,
2231         const char *page,
2232         size_t count)
2233 {
2234         unsigned long tmp;
2235         int ret;
2236
2237         ret = kstrtoul(page, 0, &tmp);
2238         if (ret < 0) {
2239                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2240                 return ret;
2241         }
2242         if ((tmp != 0) && (tmp != 1)) {
2243                 pr_err("Illegal value for alua_tg_pt_write_md:"
2244                                 " %lu\n", tmp);
2245                 return -EINVAL;
2246         }
2247         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2248
2249         return count;
2250 }
2251
2252 int core_setup_alua(struct se_device *dev)
2253 {
2254         if (!(dev->transport_flags &
2255              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2256             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2257                 struct t10_alua_lu_gp_member *lu_gp_mem;
2258
2259                 /*
2260                  * Associate this struct se_device with the default ALUA
2261                  * LUN Group.
2262                  */
2263                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2264                 if (IS_ERR(lu_gp_mem))
2265                         return PTR_ERR(lu_gp_mem);
2266
2267                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2268                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2269                                 default_lu_gp);
2270                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2271
2272                 pr_debug("%s: Adding to default ALUA LU Group:"
2273                         " core/alua/lu_gps/default_lu_gp\n",
2274                         dev->transport->name);
2275         }
2276
2277         return 0;
2278 }