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 <nab@kernel.org>
  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                 /*
 168                  * Check if the Target port group and Target port descriptor list
 169                  * based on tg_pt_gp_members count will fit into the response payload.
 170                  * Otherwise, bump rd_len to let the initiator know we have exceeded
 171                  * the allocation length and the response is truncated.
 172                  */
 173                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
 174                      cmd->data_length) {
 175                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
 176                         continue;
 177                 }
 178                 /*
 179                  * PREF: Preferred target port bit, determine if this
 180                  * bit should be set for port group.
 181                  */
 182                 if (tg_pt_gp->tg_pt_gp_pref)
 183                         buf[off] = 0x80;
 184                 /*
 185                  * Set the ASYMMETRIC ACCESS State
 186                  */
 187                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_access_state & 0xff;
 188                 /*
 189                  * Set supported ASYMMETRIC ACCESS State bits
 190                  */
 191                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
 192                 /*
 193                  * TARGET PORT GROUP
 194                  */
 195                 put_unaligned_be16(tg_pt_gp->tg_pt_gp_id, &buf[off]);
 196                 off += 2;
 197
 198                 off++; /* Skip over Reserved */
 199                 /*
 200                  * STATUS CODE
 201                  */
 202                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 203                 /*
 204                  * Vendor Specific field
 205                  */
 206                 buf[off++] = 0x00;
 207                 /*
 208                  * TARGET PORT COUNT
 209                  */
 210                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 211                 rd_len += 8;
 212
 213                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 214                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 215                                 lun_tg_pt_gp_link) {
 216                         /*
 217                          * Start Target Port descriptor format
 218                          *
 219                          * See spc4r17 section 6.2.7 Table 247
 220                          */
 221                         off += 2; /* Skip over Obsolete */
 222                         /*
 223                          * Set RELATIVE TARGET PORT IDENTIFIER
 224                          */
 225                         put_unaligned_be16(lun->lun_rtpi, &buf[off]);
 226                         off += 2;
 227                         rd_len += 4;
 228                 }
 229                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 230         }
 231         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 232         /*
 233          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 234          */
 235         put_unaligned_be32(rd_len, &buf[0]);
 236
 237         /*
 238          * Fill in the Extended header parameter data format if requested
 239          */
 240         if (ext_hdr != 0) {
 241                 buf[4] = 0x10;
 242                 /*
 243                  * Set the implicit transition time (in seconds) for the application
 244                  * client to use as a base for it's transition timeout value.
 245                  *
 246                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
 247                  * this CDB was received upon to determine this value individually
 248                  * for ALUA target port group.
 249                  */
 250                 spin_lock(&cmd->se_lun->lun_tg_pt_gp_lock);
 251                 tg_pt_gp = cmd->se_lun->lun_tg_pt_gp;
 252                 if (tg_pt_gp)
 253                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
 254                 spin_unlock(&cmd->se_lun->lun_tg_pt_gp_lock);
 255         }
 256         transport_kunmap_data_sg(cmd);
 257
 258         target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, rd_len + 4);
 259         return 0;
 260 }
 261
 262 /*
 263  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
 264  *
 265  * See spc4r17 section 6.35
 266  */
 267 sense_reason_t
 268 target_emulate_set_target_port_groups(struct se_cmd *cmd)
 269 {
 270         struct se_device *dev = cmd->se_dev;
 271         struct se_lun *l_lun = cmd->se_lun;
 272         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 273         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 274         unsigned char *buf;
 275         unsigned char *ptr;
 276         sense_reason_t rc = TCM_NO_SENSE;
 277         u32 len = 4; /* Skip over RESERVED area in header */
 278         int alua_access_state, primary = 0, valid_states;
 279         u16 tg_pt_id, rtpi;
 280
 281         if (cmd->data_length < 4) {
 282                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
 283                         " small\n", cmd->data_length);
 284                 return TCM_INVALID_PARAMETER_LIST;
 285         }
 286
 287         buf = transport_kmap_data_sg(cmd);
 288         if (!buf)
 289                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 290
 291         /*
 292          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
 293          * for the local tg_pt_gp.
 294          */
 295         spin_lock(&l_lun->lun_tg_pt_gp_lock);
 296         l_tg_pt_gp = l_lun->lun_tg_pt_gp;
 297         if (!l_tg_pt_gp) {
 298                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 299                 pr_err("Unable to access l_lun->tg_pt_gp\n");
 300                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 301                 goto out;
 302         }
 303
 304         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
 305                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 306                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 307                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
 308                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 309                 goto out;
 310         }
 311         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
 312         spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 313
 314         ptr = &buf[4]; /* Skip over RESERVED area in header */
 315
 316         while (len < cmd->data_length) {
 317                 bool found = false;
 318                 alua_access_state = (ptr[0] & 0x0f);
 319                 /*
 320                  * Check the received ALUA access state, and determine if
 321                  * the state is a primary or secondary target port asymmetric
 322                  * access state.
 323                  */
 324                 rc = core_alua_check_transition(alua_access_state, valid_states,
 325                                                 &primary, 1);
 326                 if (rc) {
 327                         /*
 328                          * If the SET TARGET PORT GROUPS attempts to establish
 329                          * an invalid combination of target port asymmetric
 330                          * access states or attempts to establish an
 331                          * unsupported target port asymmetric access state,
 332                          * then the command shall be terminated with CHECK
 333                          * CONDITION status, with the sense key set to ILLEGAL
 334                          * REQUEST, and the additional sense code set to INVALID
 335                          * FIELD IN PARAMETER LIST.
 336                          */
 337                         goto out;
 338                 }
 339
 340                 /*
 341                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 342                  * specifies a primary target port asymmetric access state,
 343                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 344                  * a primary target port group for which the primary target
 345                  * port asymmetric access state shall be changed. If the
 346                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 347                  * port asymmetric access state, then the TARGET PORT GROUP OR
 348                  * TARGET PORT field specifies the relative target port
 349                  * identifier (see 3.1.120) of the target port for which the
 350                  * secondary target port asymmetric access state shall be
 351                  * changed.
 352                  */
 353                 if (primary) {
 354                         tg_pt_id = get_unaligned_be16(ptr + 2);
 355                         /*
 356                          * Locate the matching target port group ID from
 357                          * the global tg_pt_gp list
 358                          */
 359                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 360                         list_for_each_entry(tg_pt_gp,
 361                                         &dev->t10_alua.tg_pt_gps_list,
 362                                         tg_pt_gp_list) {
 363                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 364                                         continue;
 365
 366                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 367                                         continue;
 368
 369                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 370
 371                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 372
 373                                 if (!core_alua_do_port_transition(tg_pt_gp,
 374                                                 dev, l_lun, nacl,
 375                                                 alua_access_state, 1))
 376                                         found = true;
 377
 378                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 379                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 380                                 break;
 381                         }
 382                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 383                 } else {
 384                         struct se_lun *lun;
 385
 386                         /*
 387                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
 388                          * the Target Port in question for the the incoming
 389                          * SET_TARGET_PORT_GROUPS op.
 390                          */
 391                         rtpi = get_unaligned_be16(ptr + 2);
 392                         /*
 393                          * Locate the matching relative target port identifier
 394                          * for the struct se_device storage object.
 395                          */
 396                         spin_lock(&dev->se_port_lock);
 397                         list_for_each_entry(lun, &dev->dev_sep_list,
 398                                                         lun_dev_link) {
 399                                 if (lun->lun_rtpi != rtpi)
 400                                         continue;
 401
 402                                 // XXX: racy unlock
 403                                 spin_unlock(&dev->se_port_lock);
 404
 405                                 if (!core_alua_set_tg_pt_secondary_state(
 406                                                 lun, 1, 1))
 407                                         found = true;
 408
 409                                 spin_lock(&dev->se_port_lock);
 410                                 break;
 411                         }
 412                         spin_unlock(&dev->se_port_lock);
 413                 }
 414
 415                 if (!found) {
 416                         rc = TCM_INVALID_PARAMETER_LIST;
 417                         goto out;
 418                 }
 419
 420                 ptr += 4;
 421                 len += 4;
 422         }
 423
 424 out:
 425         transport_kunmap_data_sg(cmd);
 426         if (!rc)
 427                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 428         return rc;
 429 }
 430
 431 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
 432 {
 433         /*
 434          * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
 435          * The ALUA additional sense code qualifier (ASCQ) is determined
 436          * by the ALUA primary or secondary access state..
 437          */
 438         pr_debug("[%s]: ALUA TG Port not available, "
 439                 "SenseKey: NOT_READY, ASC/ASCQ: "
 440                 "0x04/0x%02x\n",
 441                 cmd->se_tfo->fabric_name, alua_ascq);
 442
 443         cmd->scsi_asc = 0x04;
 444         cmd->scsi_ascq = alua_ascq;
 445 }
 446
 447 static inline void core_alua_state_nonoptimized(
 448         struct se_cmd *cmd,
 449         unsigned char *cdb,
 450         int nonop_delay_msecs)
 451 {
 452         /*
 453          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 454          * later to determine if processing of this cmd needs to be
 455          * temporarily delayed for the Active/NonOptimized primary access state.
 456          */
 457         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 458         cmd->alua_nonop_delay = nonop_delay_msecs;
 459 }
 460
 461 static inline int core_alua_state_lba_dependent(
 462         struct se_cmd *cmd,
 463         struct t10_alua_tg_pt_gp *tg_pt_gp)
 464 {
 465         struct se_device *dev = cmd->se_dev;
 466         u64 segment_size, segment_mult, sectors, lba;
 467
 468         /* Only need to check for cdb actually containing LBAs */
 469         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
 470                 return 0;
 471
 472         spin_lock(&dev->t10_alua.lba_map_lock);
 473         segment_size = dev->t10_alua.lba_map_segment_size;
 474         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
 475         sectors = cmd->data_length / dev->dev_attrib.block_size;
 476
 477         lba = cmd->t_task_lba;
 478         while (lba < cmd->t_task_lba + sectors) {
 479                 struct t10_alua_lba_map *cur_map = NULL, *map;
 480                 struct t10_alua_lba_map_member *map_mem;
 481
 482                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
 483                                     lba_map_list) {
 484                         u64 start_lba, last_lba;
 485                         u64 first_lba = map->lba_map_first_lba;
 486
 487                         if (segment_mult) {
 488                                 u64 tmp = lba;
 489                                 start_lba = do_div(tmp, segment_size * segment_mult);
 490
 491                                 last_lba = first_lba + segment_size - 1;
 492                                 if (start_lba >= first_lba &&
 493                                     start_lba <= last_lba) {
 494                                         lba += segment_size;
 495                                         cur_map = map;
 496                                         break;
 497                                 }
 498                         } else {
 499                                 last_lba = map->lba_map_last_lba;
 500                                 if (lba >= first_lba && lba <= last_lba) {
 501                                         lba = last_lba + 1;
 502                                         cur_map = map;
 503                                         break;
 504                                 }
 505                         }
 506                 }
 507                 if (!cur_map) {
 508                         spin_unlock(&dev->t10_alua.lba_map_lock);
 509                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 510                         return 1;
 511                 }
 512                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
 513                                     lba_map_mem_list) {
 514                         if (map_mem->lba_map_mem_alua_pg_id !=
 515                             tg_pt_gp->tg_pt_gp_id)
 516                                 continue;
 517                         switch(map_mem->lba_map_mem_alua_state) {
 518                         case ALUA_ACCESS_STATE_STANDBY:
 519                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 520                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 521                                 return 1;
 522                         case ALUA_ACCESS_STATE_UNAVAILABLE:
 523                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 524                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 525                                 return 1;
 526                         default:
 527                                 break;
 528                         }
 529                 }
 530         }
 531         spin_unlock(&dev->t10_alua.lba_map_lock);
 532         return 0;
 533 }
 534
 535 static inline int core_alua_state_standby(
 536         struct se_cmd *cmd,
 537         unsigned char *cdb)
 538 {
 539         /*
 540          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 541          * spc4r17 section 5.9.2.4.4
 542          */
 543         switch (cdb[0]) {
 544         case INQUIRY:
 545         case LOG_SELECT:
 546         case LOG_SENSE:
 547         case MODE_SELECT:
 548         case MODE_SENSE:
 549         case REPORT_LUNS:
 550         case RECEIVE_DIAGNOSTIC:
 551         case SEND_DIAGNOSTIC:
 552         case READ_CAPACITY:
 553                 return 0;
 554         case SERVICE_ACTION_IN_16:
 555                 switch (cdb[1] & 0x1f) {
 556                 case SAI_READ_CAPACITY_16:
 557                         return 0;
 558                 default:
 559                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 560                         return 1;
 561                 }
 562         case MAINTENANCE_IN:
 563                 switch (cdb[1] & 0x1f) {
 564                 case MI_REPORT_TARGET_PGS:
 565                         return 0;
 566                 default:
 567                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 568                         return 1;
 569                 }
 570         case MAINTENANCE_OUT:
 571                 switch (cdb[1]) {
 572                 case MO_SET_TARGET_PGS:
 573                         return 0;
 574                 default:
 575                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 576                         return 1;
 577                 }
 578         case REQUEST_SENSE:
 579         case PERSISTENT_RESERVE_IN:
 580         case PERSISTENT_RESERVE_OUT:
 581         case READ_BUFFER:
 582         case WRITE_BUFFER:
 583                 return 0;
 584         default:
 585                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 586                 return 1;
 587         }
 588
 589         return 0;
 590 }
 591
 592 static inline int core_alua_state_unavailable(
 593         struct se_cmd *cmd,
 594         unsigned char *cdb)
 595 {
 596         /*
 597          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 598          * spc4r17 section 5.9.2.4.5
 599          */
 600         switch (cdb[0]) {
 601         case INQUIRY:
 602         case REPORT_LUNS:
 603                 return 0;
 604         case MAINTENANCE_IN:
 605                 switch (cdb[1] & 0x1f) {
 606                 case MI_REPORT_TARGET_PGS:
 607                         return 0;
 608                 default:
 609                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 610                         return 1;
 611                 }
 612         case MAINTENANCE_OUT:
 613                 switch (cdb[1]) {
 614                 case MO_SET_TARGET_PGS:
 615                         return 0;
 616                 default:
 617                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 618                         return 1;
 619                 }
 620         case REQUEST_SENSE:
 621         case READ_BUFFER:
 622         case WRITE_BUFFER:
 623                 return 0;
 624         default:
 625                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 626                 return 1;
 627         }
 628
 629         return 0;
 630 }
 631
 632 static inline int core_alua_state_transition(
 633         struct se_cmd *cmd,
 634         unsigned char *cdb)
 635 {
 636         /*
 637          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
 638          * spc4r17 section 5.9.2.5
 639          */
 640         switch (cdb[0]) {
 641         case INQUIRY:
 642         case REPORT_LUNS:
 643                 return 0;
 644         case MAINTENANCE_IN:
 645                 switch (cdb[1] & 0x1f) {
 646                 case MI_REPORT_TARGET_PGS:
 647                         return 0;
 648                 default:
 649                         set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 650                         return 1;
 651                 }
 652         case REQUEST_SENSE:
 653         case READ_BUFFER:
 654         case WRITE_BUFFER:
 655                 return 0;
 656         default:
 657                 set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 658                 return 1;
 659         }
 660
 661         return 0;
 662 }
 663
 664 /*
 665  * return 1: Is used to signal LUN not accessible, and check condition/not ready
 666  * return 0: Used to signal success
 667  * return -1: Used to signal failure, and invalid cdb field
 668  */
 669 sense_reason_t
 670 target_alua_state_check(struct se_cmd *cmd)
 671 {
 672         struct se_device *dev = cmd->se_dev;
 673         unsigned char *cdb = cmd->t_task_cdb;
 674         struct se_lun *lun = cmd->se_lun;
 675         struct t10_alua_tg_pt_gp *tg_pt_gp;
 676         int out_alua_state, nonop_delay_msecs;
 677
 678         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
 679                 return 0;
 680         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
 681                 return 0;
 682
 683         /*
 684          * First, check for a struct se_port specific secondary ALUA target port
 685          * access state: OFFLINE
 686          */
 687         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
 688                 pr_debug("ALUA: Got secondary offline status for local"
 689                                 " target port\n");
 690                 set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
 691                 return TCM_CHECK_CONDITION_NOT_READY;
 692         }
 693
 694         if (!lun->lun_tg_pt_gp)
 695                 return 0;
 696
 697         spin_lock(&lun->lun_tg_pt_gp_lock);
 698         tg_pt_gp = lun->lun_tg_pt_gp;
 699         out_alua_state = tg_pt_gp->tg_pt_gp_alua_access_state;
 700         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 701
 702         // XXX: keeps using tg_pt_gp witout reference after unlock
 703         spin_unlock(&lun->lun_tg_pt_gp_lock);
 704         /*
 705          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
 706          * statement so the compiler knows explicitly to check this case first.
 707          * For the Optimized ALUA access state case, we want to process the
 708          * incoming fabric cmd ASAP..
 709          */
 710         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
 711                 return 0;
 712
 713         switch (out_alua_state) {
 714         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 715                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
 716                 break;
 717         case ALUA_ACCESS_STATE_STANDBY:
 718                 if (core_alua_state_standby(cmd, cdb))
 719                         return TCM_CHECK_CONDITION_NOT_READY;
 720                 break;
 721         case ALUA_ACCESS_STATE_UNAVAILABLE:
 722                 if (core_alua_state_unavailable(cmd, cdb))
 723                         return TCM_CHECK_CONDITION_NOT_READY;
 724                 break;
 725         case ALUA_ACCESS_STATE_TRANSITION:
 726                 if (core_alua_state_transition(cmd, cdb))
 727                         return TCM_CHECK_CONDITION_NOT_READY;
 728                 break;
 729         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 730                 if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
 731                         return TCM_CHECK_CONDITION_NOT_READY;
 732                 break;
 733         /*
 734          * OFFLINE is a secondary ALUA target port group access state, that is
 735          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
 736          */
 737         case ALUA_ACCESS_STATE_OFFLINE:
 738         default:
 739                 pr_err("Unknown ALUA access state: 0x%02x\n",
 740                                 out_alua_state);
 741                 return TCM_INVALID_CDB_FIELD;
 742         }
 743
 744         return 0;
 745 }
 746
 747 /*
 748  * Check implicit and explicit ALUA state change request.
 749  */
 750 static sense_reason_t
 751 core_alua_check_transition(int state, int valid, int *primary, int explicit)
 752 {
 753         /*
 754          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 755          * defined as primary target port asymmetric access states.
 756          */
 757         switch (state) {
 758         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 759                 if (!(valid & ALUA_AO_SUP))
 760                         goto not_supported;
 761                 *primary = 1;
 762                 break;
 763         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 764                 if (!(valid & ALUA_AN_SUP))
 765                         goto not_supported;
 766                 *primary = 1;
 767                 break;
 768         case ALUA_ACCESS_STATE_STANDBY:
 769                 if (!(valid & ALUA_S_SUP))
 770                         goto not_supported;
 771                 *primary = 1;
 772                 break;
 773         case ALUA_ACCESS_STATE_UNAVAILABLE:
 774                 if (!(valid & ALUA_U_SUP))
 775                         goto not_supported;
 776                 *primary = 1;
 777                 break;
 778         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 779                 if (!(valid & ALUA_LBD_SUP))
 780                         goto not_supported;
 781                 *primary = 1;
 782                 break;
 783         case ALUA_ACCESS_STATE_OFFLINE:
 784                 /*
 785                  * OFFLINE state is defined as a secondary target port
 786                  * asymmetric access state.
 787                  */
 788                 if (!(valid & ALUA_O_SUP))
 789                         goto not_supported;
 790                 *primary = 0;
 791                 break;
 792         case ALUA_ACCESS_STATE_TRANSITION:
 793                 if (!(valid & ALUA_T_SUP) || explicit)
 794                         /*
 795                          * Transitioning is set internally and by tcmu daemon,
 796                          * and cannot be selected through a STPG.
 797                          */
 798                         goto not_supported;
 799                 *primary = 0;
 800                 break;
 801         default:
 802                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 803                 return TCM_INVALID_PARAMETER_LIST;
 804         }
 805
 806         return 0;
 807
 808 not_supported:
 809         pr_err("ALUA access state %s not supported",
 810                core_alua_dump_state(state));
 811         return TCM_INVALID_PARAMETER_LIST;
 812 }
 813
 814 static char *core_alua_dump_state(int state)
 815 {
 816         switch (state) {
 817         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 818                 return "Active/Optimized";
 819         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 820                 return "Active/NonOptimized";
 821         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 822                 return "LBA Dependent";
 823         case ALUA_ACCESS_STATE_STANDBY:
 824                 return "Standby";
 825         case ALUA_ACCESS_STATE_UNAVAILABLE:
 826                 return "Unavailable";
 827         case ALUA_ACCESS_STATE_OFFLINE:
 828                 return "Offline";
 829         case ALUA_ACCESS_STATE_TRANSITION:
 830                 return "Transitioning";
 831         default:
 832                 return "Unknown";
 833         }
 834
 835         return NULL;
 836 }
 837
 838 char *core_alua_dump_status(int status)
 839 {
 840         switch (status) {
 841         case ALUA_STATUS_NONE:
 842                 return "None";
 843         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
 844                 return "Altered by Explicit STPG";
 845         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
 846                 return "Altered by Implicit ALUA";
 847         default:
 848                 return "Unknown";
 849         }
 850
 851         return NULL;
 852 }
 853
 854 /*
 855  * Used by fabric modules to determine when we need to delay processing
 856  * for the Active/NonOptimized paths..
 857  */
 858 int core_alua_check_nonop_delay(
 859         struct se_cmd *cmd)
 860 {
 861         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 862                 return 0;
 863         /*
 864          * The ALUA Active/NonOptimized access state delay can be disabled
 865          * in via configfs with a value of zero
 866          */
 867         if (!cmd->alua_nonop_delay)
 868                 return 0;
 869         /*
 870          * struct se_cmd->alua_nonop_delay gets set by a target port group
 871          * defined interval in core_alua_state_nonoptimized()
 872          */
 873         msleep_interruptible(cmd->alua_nonop_delay);
 874         return 0;
 875 }
 876 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 877
 878 static int core_alua_write_tpg_metadata(
 879         const char *path,
 880         unsigned char *md_buf,
 881         u32 md_buf_len)
 882 {
 883         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
 884         loff_t pos = 0;
 885         int ret;
 886
 887         if (IS_ERR(file)) {
 888                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
 889                 return -ENODEV;
 890         }
 891         ret = kernel_write(file, md_buf, md_buf_len, &pos);
 892         if (ret < 0)
 893                 pr_err("Error writing ALUA metadata file: %s\n", path);
 894         fput(file);
 895         return (ret < 0) ? -EIO : 0;
 896 }
 897
 898 static int core_alua_update_tpg_primary_metadata(
 899         struct t10_alua_tg_pt_gp *tg_pt_gp)
 900 {
 901         unsigned char *md_buf;
 902         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
 903         char *path;
 904         int len, rc;
 905
 906         lockdep_assert_held(&tg_pt_gp->tg_pt_gp_transition_mutex);
 907
 908         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
 909         if (!md_buf) {
 910                 pr_err("Unable to allocate buf for ALUA metadata\n");
 911                 return -ENOMEM;
 912         }
 913
 914         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
 915                         "tg_pt_gp_id=%hu\n"
 916                         "alua_access_state=0x%02x\n"
 917                         "alua_access_status=0x%02x\n",
 918                         tg_pt_gp->tg_pt_gp_id,
 919                         tg_pt_gp->tg_pt_gp_alua_access_state,
 920                         tg_pt_gp->tg_pt_gp_alua_access_status);
 921
 922         rc = -ENOMEM;
 923         path = kasprintf(GFP_KERNEL, "%s/alua/tpgs_%s/%s", db_root,
 924                         &wwn->unit_serial[0],
 925                         config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 926         if (path) {
 927                 rc = core_alua_write_tpg_metadata(path, md_buf, len);
 928                 kfree(path);
 929         }
 930         kfree(md_buf);
 931         return rc;
 932 }
 933
 934 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
 935 {
 936         struct se_dev_entry *se_deve;
 937         struct se_lun *lun;
 938         struct se_lun_acl *lacl;
 939
 940         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 941         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 942                                 lun_tg_pt_gp_link) {
 943                 /*
 944                  * After an implicit target port asymmetric access state
 945                  * change, a device server shall establish a unit attention
 946                  * condition for the initiator port associated with every I_T
 947                  * nexus with the additional sense code set to ASYMMETRIC
 948                  * ACCESS STATE CHANGED.
 949                  *
 950                  * After an explicit target port asymmetric access state
 951                  * change, a device server shall establish a unit attention
 952                  * condition with the additional sense code set to ASYMMETRIC
 953                  * ACCESS STATE CHANGED for the initiator port associated with
 954                  * every I_T nexus other than the I_T nexus on which the SET
 955                  * TARGET PORT GROUPS command
 956                  */
 957                 if (!percpu_ref_tryget_live(&lun->lun_ref))
 958                         continue;
 959                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 960
 961                 spin_lock(&lun->lun_deve_lock);
 962                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
 963                         lacl = rcu_dereference_check(se_deve->se_lun_acl,
 964                                         lockdep_is_held(&lun->lun_deve_lock));
 965
 966                         /*
 967                          * spc4r37 p.242:
 968                          * After an explicit target port asymmetric access
 969                          * state change, a device server shall establish a
 970                          * unit attention condition with the additional sense
 971                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
 972                          * the initiator port associated with every I_T nexus
 973                          * other than the I_T nexus on which the SET TARGET
 974                          * PORT GROUPS command was received.
 975                          */
 976                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
 977                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
 978                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
 979                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
 980                                 continue;
 981
 982                         /*
 983                          * se_deve->se_lun_acl pointer may be NULL for a
 984                          * entry created without explicit Node+MappedLUN ACLs
 985                          */
 986                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
 987                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
 988                                 continue;
 989
 990                         core_scsi3_ua_allocate(se_deve, 0x2A,
 991                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
 992                 }
 993                 spin_unlock(&lun->lun_deve_lock);
 994
 995                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 996                 percpu_ref_put(&lun->lun_ref);
 997         }
 998         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 999 }
1000
1001 static int core_alua_do_transition_tg_pt(
1002         struct t10_alua_tg_pt_gp *tg_pt_gp,
1003         int new_state,
1004         int explicit)
1005 {
1006         int prev_state;
1007
1008         mutex_lock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1009         /* Nothing to be done here */
1010         if (tg_pt_gp->tg_pt_gp_alua_access_state == new_state) {
1011                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1012                 return 0;
1013         }
1014
1015         if (explicit && new_state == ALUA_ACCESS_STATE_TRANSITION) {
1016                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1017                 return -EAGAIN;
1018         }
1019
1020         /*
1021          * Save the old primary ALUA access state, and set the current state
1022          * to ALUA_ACCESS_STATE_TRANSITION.
1023          */
1024         prev_state = tg_pt_gp->tg_pt_gp_alua_access_state;
1025         tg_pt_gp->tg_pt_gp_alua_access_state = ALUA_ACCESS_STATE_TRANSITION;
1026         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1027                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1028                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1029
1030         core_alua_queue_state_change_ua(tg_pt_gp);
1031
1032         if (new_state == ALUA_ACCESS_STATE_TRANSITION) {
1033                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1034                 return 0;
1035         }
1036
1037         /*
1038          * Check for the optional ALUA primary state transition delay
1039          */
1040         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1041                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1042
1043         /*
1044          * Set the current primary ALUA access state to the requested new state
1045          */
1046         tg_pt_gp->tg_pt_gp_alua_access_state = new_state;
1047
1048         /*
1049          * Update the ALUA metadata buf that has been allocated in
1050          * core_alua_do_port_transition(), this metadata will be written
1051          * to struct file.
1052          *
1053          * Note that there is the case where we do not want to update the
1054          * metadata when the saved metadata is being parsed in userspace
1055          * when setting the existing port access state and access status.
1056          *
1057          * Also note that the failure to write out the ALUA metadata to
1058          * struct file does NOT affect the actual ALUA transition.
1059          */
1060         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1061                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1062         }
1063
1064         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1065                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1066                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1067                 tg_pt_gp->tg_pt_gp_id,
1068                 core_alua_dump_state(prev_state),
1069                 core_alua_dump_state(new_state));
1070
1071         core_alua_queue_state_change_ua(tg_pt_gp);
1072
1073         mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1074         return 0;
1075 }
1076
1077 int core_alua_do_port_transition(
1078         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1079         struct se_device *l_dev,
1080         struct se_lun *l_lun,
1081         struct se_node_acl *l_nacl,
1082         int new_state,
1083         int explicit)
1084 {
1085         struct se_device *dev;
1086         struct t10_alua_lu_gp *lu_gp;
1087         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1088         struct t10_alua_tg_pt_gp *tg_pt_gp;
1089         int primary, valid_states, rc = 0;
1090
1091         if (l_dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
1092                 return -ENODEV;
1093
1094         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1095         if (core_alua_check_transition(new_state, valid_states, &primary,
1096                                        explicit) != 0)
1097                 return -EINVAL;
1098
1099         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1100         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1101         lu_gp = local_lu_gp_mem->lu_gp;
1102         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1103         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1104         /*
1105          * For storage objects that are members of the 'default_lu_gp',
1106          * we only do transition on the passed *l_tp_pt_gp, and not
1107          * on all of the matching target port groups IDs in default_lu_gp.
1108          */
1109         if (!lu_gp->lu_gp_id) {
1110                 /*
1111                  * core_alua_do_transition_tg_pt() will always return
1112                  * success.
1113                  */
1114                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1115                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1116                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1117                                                    new_state, explicit);
1118                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1119                 return rc;
1120         }
1121         /*
1122          * For all other LU groups aside from 'default_lu_gp', walk all of
1123          * the associated storage objects looking for a matching target port
1124          * group ID from the local target port group.
1125          */
1126         spin_lock(&lu_gp->lu_gp_lock);
1127         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1128                                 lu_gp_mem_list) {
1129
1130                 dev = lu_gp_mem->lu_gp_mem_dev;
1131                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1132                 spin_unlock(&lu_gp->lu_gp_lock);
1133
1134                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1135                 list_for_each_entry(tg_pt_gp,
1136                                 &dev->t10_alua.tg_pt_gps_list,
1137                                 tg_pt_gp_list) {
1138
1139                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1140                                 continue;
1141                         /*
1142                          * If the target behavior port asymmetric access state
1143                          * is changed for any target port group accessible via
1144                          * a logical unit within a LU group, the target port
1145                          * behavior group asymmetric access states for the same
1146                          * target port group accessible via other logical units
1147                          * in that LU group will also change.
1148                          */
1149                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1150                                 continue;
1151
1152                         if (l_tg_pt_gp == tg_pt_gp) {
1153                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1154                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1155                         } else {
1156                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1157                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1158                         }
1159                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1160                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1161                         /*
1162                          * core_alua_do_transition_tg_pt() will always return
1163                          * success.
1164                          */
1165                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1166                                         new_state, explicit);
1167
1168                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1169                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1170                         if (rc)
1171                                 break;
1172                 }
1173                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1174
1175                 spin_lock(&lu_gp->lu_gp_lock);
1176                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1177         }
1178         spin_unlock(&lu_gp->lu_gp_lock);
1179
1180         if (!rc) {
1181                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1182                          " Group IDs: %hu %s transition to primary state: %s\n",
1183                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1184                          l_tg_pt_gp->tg_pt_gp_id,
1185                          (explicit) ? "explicit" : "implicit",
1186                          core_alua_dump_state(new_state));
1187         }
1188
1189         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1190         return rc;
1191 }
1192
1193 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1194 {
1195         struct se_portal_group *se_tpg = lun->lun_tpg;
1196         unsigned char *md_buf;
1197         char *path;
1198         int len, rc;
1199
1200         mutex_lock(&lun->lun_tg_pt_md_mutex);
1201
1202         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1203         if (!md_buf) {
1204                 pr_err("Unable to allocate buf for ALUA metadata\n");
1205                 rc = -ENOMEM;
1206                 goto out_unlock;
1207         }
1208
1209         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1210                         "alua_tg_pt_status=0x%02x\n",
1211                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1212                         lun->lun_tg_pt_secondary_stat);
1213
1214         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) {
1215                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s+%hu/lun_%llu",
1216                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1217                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1218                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
1219                                 lun->unpacked_lun);
1220         } else {
1221                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s/lun_%llu",
1222                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1223                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1224                                 lun->unpacked_lun);
1225         }
1226         if (!path) {
1227                 rc = -ENOMEM;
1228                 goto out_free;
1229         }
1230
1231         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1232         kfree(path);
1233 out_free:
1234         kfree(md_buf);
1235 out_unlock:
1236         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1237         return rc;
1238 }
1239
1240 static int core_alua_set_tg_pt_secondary_state(
1241         struct se_lun *lun,
1242         int explicit,
1243         int offline)
1244 {
1245         struct t10_alua_tg_pt_gp *tg_pt_gp;
1246         int trans_delay_msecs;
1247
1248         spin_lock(&lun->lun_tg_pt_gp_lock);
1249         tg_pt_gp = lun->lun_tg_pt_gp;
1250         if (!tg_pt_gp) {
1251                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1252                 pr_err("Unable to complete secondary state"
1253                                 " transition\n");
1254                 return -EINVAL;
1255         }
1256         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1257         /*
1258          * Set the secondary ALUA target port access state to OFFLINE
1259          * or release the previously secondary state for struct se_lun
1260          */
1261         if (offline)
1262                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1263         else
1264                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1265
1266         lun->lun_tg_pt_secondary_stat = (explicit) ?
1267                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1268                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1269
1270         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1271                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1272                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1273                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1274
1275         spin_unlock(&lun->lun_tg_pt_gp_lock);
1276         /*
1277          * Do the optional transition delay after we set the secondary
1278          * ALUA access state.
1279          */
1280         if (trans_delay_msecs != 0)
1281                 msleep_interruptible(trans_delay_msecs);
1282         /*
1283          * See if we need to update the ALUA fabric port metadata for
1284          * secondary state and status
1285          */
1286         if (lun->lun_tg_pt_secondary_write_md)
1287                 core_alua_update_tpg_secondary_metadata(lun);
1288
1289         return 0;
1290 }
1291
1292 struct t10_alua_lba_map *
1293 core_alua_allocate_lba_map(struct list_head *list,
1294                            u64 first_lba, u64 last_lba)
1295 {
1296         struct t10_alua_lba_map *lba_map;
1297
1298         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1299         if (!lba_map) {
1300                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1301                 return ERR_PTR(-ENOMEM);
1302         }
1303         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1304         lba_map->lba_map_first_lba = first_lba;
1305         lba_map->lba_map_last_lba = last_lba;
1306
1307         list_add_tail(&lba_map->lba_map_list, list);
1308         return lba_map;
1309 }
1310
1311 int
1312 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1313                                int pg_id, int state)
1314 {
1315         struct t10_alua_lba_map_member *lba_map_mem;
1316
1317         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1318                             lba_map_mem_list) {
1319                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1320                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1321                         return -EINVAL;
1322                 }
1323         }
1324
1325         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1326         if (!lba_map_mem) {
1327                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1328                 return -ENOMEM;
1329         }
1330         lba_map_mem->lba_map_mem_alua_state = state;
1331         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1332
1333         list_add_tail(&lba_map_mem->lba_map_mem_list,
1334                       &lba_map->lba_map_mem_list);
1335         return 0;
1336 }
1337
1338 void
1339 core_alua_free_lba_map(struct list_head *lba_list)
1340 {
1341         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1342         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1343
1344         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1345                                  lba_map_list) {
1346                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1347                                          &lba_map->lba_map_mem_list,
1348                                          lba_map_mem_list) {
1349                         list_del(&lba_map_mem->lba_map_mem_list);
1350                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1351                                         lba_map_mem);
1352                 }
1353                 list_del(&lba_map->lba_map_list);
1354                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1355         }
1356 }
1357
1358 void
1359 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1360                       int segment_size, int segment_mult)
1361 {
1362         struct list_head old_lba_map_list;
1363         struct t10_alua_tg_pt_gp *tg_pt_gp;
1364         int activate = 0, supported;
1365
1366         INIT_LIST_HEAD(&old_lba_map_list);
1367         spin_lock(&dev->t10_alua.lba_map_lock);
1368         dev->t10_alua.lba_map_segment_size = segment_size;
1369         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1370         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1371         if (lba_map_list) {
1372                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1373                 activate = 1;
1374         }
1375         spin_unlock(&dev->t10_alua.lba_map_lock);
1376         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1377         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1378                             tg_pt_gp_list) {
1379
1380                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1381                         continue;
1382                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1383                 if (activate)
1384                         supported |= ALUA_LBD_SUP;
1385                 else
1386                         supported &= ~ALUA_LBD_SUP;
1387                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1388         }
1389         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1390         core_alua_free_lba_map(&old_lba_map_list);
1391 }
1392
1393 struct t10_alua_lu_gp *
1394 core_alua_allocate_lu_gp(const char *name, int def_group)
1395 {
1396         struct t10_alua_lu_gp *lu_gp;
1397
1398         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1399         if (!lu_gp) {
1400                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1401                 return ERR_PTR(-ENOMEM);
1402         }
1403         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1404         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1405         spin_lock_init(&lu_gp->lu_gp_lock);
1406         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1407
1408         if (def_group) {
1409                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1410                 lu_gp->lu_gp_valid_id = 1;
1411                 alua_lu_gps_count++;
1412         }
1413
1414         return lu_gp;
1415 }
1416
1417 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1418 {
1419         struct t10_alua_lu_gp *lu_gp_tmp;
1420         u16 lu_gp_id_tmp;
1421         /*
1422          * The lu_gp->lu_gp_id may only be set once..
1423          */
1424         if (lu_gp->lu_gp_valid_id) {
1425                 pr_warn("ALUA LU Group already has a valid ID,"
1426                         " ignoring request\n");
1427                 return -EINVAL;
1428         }
1429
1430         spin_lock(&lu_gps_lock);
1431         if (alua_lu_gps_count == 0x0000ffff) {
1432                 pr_err("Maximum ALUA alua_lu_gps_count:"
1433                                 " 0x0000ffff reached\n");
1434                 spin_unlock(&lu_gps_lock);
1435                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1436                 return -ENOSPC;
1437         }
1438 again:
1439         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1440                                 alua_lu_gps_counter++;
1441
1442         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1443                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1444                         if (!lu_gp_id)
1445                                 goto again;
1446
1447                         pr_warn("ALUA Logical Unit Group ID: %hu"
1448                                 " already exists, ignoring request\n",
1449                                 lu_gp_id);
1450                         spin_unlock(&lu_gps_lock);
1451                         return -EINVAL;
1452                 }
1453         }
1454
1455         lu_gp->lu_gp_id = lu_gp_id_tmp;
1456         lu_gp->lu_gp_valid_id = 1;
1457         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1458         alua_lu_gps_count++;
1459         spin_unlock(&lu_gps_lock);
1460
1461         return 0;
1462 }
1463
1464 static struct t10_alua_lu_gp_member *
1465 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1466 {
1467         struct t10_alua_lu_gp_member *lu_gp_mem;
1468
1469         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1470         if (!lu_gp_mem) {
1471                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1472                 return ERR_PTR(-ENOMEM);
1473         }
1474         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1475         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1476         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1477
1478         lu_gp_mem->lu_gp_mem_dev = dev;
1479         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1480
1481         return lu_gp_mem;
1482 }
1483
1484 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1485 {
1486         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1487         /*
1488          * Once we have reached this point, config_item_put() has
1489          * already been called from target_core_alua_drop_lu_gp().
1490          *
1491          * Here, we remove the *lu_gp from the global list so that
1492          * no associations can be made while we are releasing
1493          * struct t10_alua_lu_gp.
1494          */
1495         spin_lock(&lu_gps_lock);
1496         list_del(&lu_gp->lu_gp_node);
1497         alua_lu_gps_count--;
1498         spin_unlock(&lu_gps_lock);
1499         /*
1500          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1501          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1502          * released with core_alua_put_lu_gp_from_name()
1503          */
1504         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1505                 cpu_relax();
1506         /*
1507          * Release reference to struct t10_alua_lu_gp * from all associated
1508          * struct se_device.
1509          */
1510         spin_lock(&lu_gp->lu_gp_lock);
1511         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1512                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1513                 if (lu_gp_mem->lu_gp_assoc) {
1514                         list_del(&lu_gp_mem->lu_gp_mem_list);
1515                         lu_gp->lu_gp_members--;
1516                         lu_gp_mem->lu_gp_assoc = 0;
1517                 }
1518                 spin_unlock(&lu_gp->lu_gp_lock);
1519                 /*
1520                  *
1521                  * lu_gp_mem is associated with a single
1522                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1523                  * struct se_device is released via core_alua_free_lu_gp_mem().
1524                  *
1525                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1526                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1527                  */
1528                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1529                 if (lu_gp != default_lu_gp)
1530                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1531                                         default_lu_gp);
1532                 else
1533                         lu_gp_mem->lu_gp = NULL;
1534                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1535
1536                 spin_lock(&lu_gp->lu_gp_lock);
1537         }
1538         spin_unlock(&lu_gp->lu_gp_lock);
1539
1540         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1541 }
1542
1543 void core_alua_free_lu_gp_mem(struct se_device *dev)
1544 {
1545         struct t10_alua_lu_gp *lu_gp;
1546         struct t10_alua_lu_gp_member *lu_gp_mem;
1547
1548         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1549         if (!lu_gp_mem)
1550                 return;
1551
1552         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1553                 cpu_relax();
1554
1555         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1556         lu_gp = lu_gp_mem->lu_gp;
1557         if (lu_gp) {
1558                 spin_lock(&lu_gp->lu_gp_lock);
1559                 if (lu_gp_mem->lu_gp_assoc) {
1560                         list_del(&lu_gp_mem->lu_gp_mem_list);
1561                         lu_gp->lu_gp_members--;
1562                         lu_gp_mem->lu_gp_assoc = 0;
1563                 }
1564                 spin_unlock(&lu_gp->lu_gp_lock);
1565                 lu_gp_mem->lu_gp = NULL;
1566         }
1567         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1568
1569         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1570 }
1571
1572 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1573 {
1574         struct t10_alua_lu_gp *lu_gp;
1575         struct config_item *ci;
1576
1577         spin_lock(&lu_gps_lock);
1578         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1579                 if (!lu_gp->lu_gp_valid_id)
1580                         continue;
1581                 ci = &lu_gp->lu_gp_group.cg_item;
1582                 if (!strcmp(config_item_name(ci), name)) {
1583                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1584                         spin_unlock(&lu_gps_lock);
1585                         return lu_gp;
1586                 }
1587         }
1588         spin_unlock(&lu_gps_lock);
1589
1590         return NULL;
1591 }
1592
1593 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1594 {
1595         spin_lock(&lu_gps_lock);
1596         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1597         spin_unlock(&lu_gps_lock);
1598 }
1599
1600 /*
1601  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1602  */
1603 void __core_alua_attach_lu_gp_mem(
1604         struct t10_alua_lu_gp_member *lu_gp_mem,
1605         struct t10_alua_lu_gp *lu_gp)
1606 {
1607         spin_lock(&lu_gp->lu_gp_lock);
1608         lu_gp_mem->lu_gp = lu_gp;
1609         lu_gp_mem->lu_gp_assoc = 1;
1610         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1611         lu_gp->lu_gp_members++;
1612         spin_unlock(&lu_gp->lu_gp_lock);
1613 }
1614
1615 /*
1616  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1617  */
1618 void __core_alua_drop_lu_gp_mem(
1619         struct t10_alua_lu_gp_member *lu_gp_mem,
1620         struct t10_alua_lu_gp *lu_gp)
1621 {
1622         spin_lock(&lu_gp->lu_gp_lock);
1623         list_del(&lu_gp_mem->lu_gp_mem_list);
1624         lu_gp_mem->lu_gp = NULL;
1625         lu_gp_mem->lu_gp_assoc = 0;
1626         lu_gp->lu_gp_members--;
1627         spin_unlock(&lu_gp->lu_gp_lock);
1628 }
1629
1630 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1631                 const char *name, int def_group)
1632 {
1633         struct t10_alua_tg_pt_gp *tg_pt_gp;
1634
1635         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1636         if (!tg_pt_gp) {
1637                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1638                 return NULL;
1639         }
1640         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1641         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1642         mutex_init(&tg_pt_gp->tg_pt_gp_transition_mutex);
1643         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1644         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1645         tg_pt_gp->tg_pt_gp_dev = dev;
1646         tg_pt_gp->tg_pt_gp_alua_access_state =
1647                         ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED;
1648         /*
1649          * Enable both explicit and implicit ALUA support by default
1650          */
1651         tg_pt_gp->tg_pt_gp_alua_access_type =
1652                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1653         /*
1654          * Set the default Active/NonOptimized Delay in milliseconds
1655          */
1656         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1657         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1658         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1659
1660         /*
1661          * Enable all supported states
1662          */
1663         tg_pt_gp->tg_pt_gp_alua_supported_states =
1664             ALUA_T_SUP | ALUA_O_SUP |
1665             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1666
1667         if (def_group) {
1668                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1669                 tg_pt_gp->tg_pt_gp_id =
1670                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1671                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1672                 dev->t10_alua.alua_tg_pt_gps_count++;
1673                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1674                               &dev->t10_alua.tg_pt_gps_list);
1675                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1676         }
1677
1678         return tg_pt_gp;
1679 }
1680
1681 int core_alua_set_tg_pt_gp_id(
1682         struct t10_alua_tg_pt_gp *tg_pt_gp,
1683         u16 tg_pt_gp_id)
1684 {
1685         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1686         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1687         u16 tg_pt_gp_id_tmp;
1688
1689         /*
1690          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1691          */
1692         if (tg_pt_gp->tg_pt_gp_valid_id) {
1693                 pr_warn("ALUA TG PT Group already has a valid ID,"
1694                         " ignoring request\n");
1695                 return -EINVAL;
1696         }
1697
1698         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1699         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1700                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1701                         " 0x0000ffff reached\n");
1702                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1703                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1704                 return -ENOSPC;
1705         }
1706 again:
1707         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1708                         dev->t10_alua.alua_tg_pt_gps_counter++;
1709
1710         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1711                         tg_pt_gp_list) {
1712                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1713                         if (!tg_pt_gp_id)
1714                                 goto again;
1715
1716                         pr_err("ALUA Target Port Group ID: %hu already"
1717                                 " exists, ignoring request\n", tg_pt_gp_id);
1718                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1719                         return -EINVAL;
1720                 }
1721         }
1722
1723         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1724         tg_pt_gp->tg_pt_gp_valid_id = 1;
1725         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1726                         &dev->t10_alua.tg_pt_gps_list);
1727         dev->t10_alua.alua_tg_pt_gps_count++;
1728         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1729
1730         return 0;
1731 }
1732
1733 void core_alua_free_tg_pt_gp(
1734         struct t10_alua_tg_pt_gp *tg_pt_gp)
1735 {
1736         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1737         struct se_lun *lun, *next;
1738
1739         /*
1740          * Once we have reached this point, config_item_put() has already
1741          * been called from target_core_alua_drop_tg_pt_gp().
1742          *
1743          * Here we remove *tg_pt_gp from the global list so that
1744          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1745          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1746          */
1747         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1748         if (tg_pt_gp->tg_pt_gp_valid_id) {
1749                 list_del(&tg_pt_gp->tg_pt_gp_list);
1750                 dev->t10_alua.alua_tg_pt_gps_count--;
1751         }
1752         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1753
1754         /*
1755          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1756          * core_alua_get_tg_pt_gp_by_name() in
1757          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1758          * to be released with core_alua_put_tg_pt_gp_from_name().
1759          */
1760         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1761                 cpu_relax();
1762
1763         /*
1764          * Release reference to struct t10_alua_tg_pt_gp from all associated
1765          * struct se_port.
1766          */
1767         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1768         list_for_each_entry_safe(lun, next,
1769                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1770                 list_del_init(&lun->lun_tg_pt_gp_link);
1771                 tg_pt_gp->tg_pt_gp_members--;
1772
1773                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1774                 /*
1775                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1776                  * assume we want to re-associate a given tg_pt_gp_mem with
1777                  * default_tg_pt_gp.
1778                  */
1779                 spin_lock(&lun->lun_tg_pt_gp_lock);
1780                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1781                         __target_attach_tg_pt_gp(lun,
1782                                         dev->t10_alua.default_tg_pt_gp);
1783                 } else
1784                         lun->lun_tg_pt_gp = NULL;
1785                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1786
1787                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1788         }
1789         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1790
1791         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1792 }
1793
1794 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1795                 struct se_device *dev, const char *name)
1796 {
1797         struct t10_alua_tg_pt_gp *tg_pt_gp;
1798         struct config_item *ci;
1799
1800         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1801         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1802                         tg_pt_gp_list) {
1803                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1804                         continue;
1805                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1806                 if (!strcmp(config_item_name(ci), name)) {
1807                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1808                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1809                         return tg_pt_gp;
1810                 }
1811         }
1812         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1813
1814         return NULL;
1815 }
1816
1817 static void core_alua_put_tg_pt_gp_from_name(
1818         struct t10_alua_tg_pt_gp *tg_pt_gp)
1819 {
1820         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1821
1822         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1823         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1824         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1825 }
1826
1827 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1828                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1829 {
1830         struct se_dev_entry *se_deve;
1831
1832         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1833
1834         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1835         lun->lun_tg_pt_gp = tg_pt_gp;
1836         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1837         tg_pt_gp->tg_pt_gp_members++;
1838         spin_lock(&lun->lun_deve_lock);
1839         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1840                 core_scsi3_ua_allocate(se_deve, 0x3f,
1841                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1842         spin_unlock(&lun->lun_deve_lock);
1843         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1844 }
1845
1846 void target_attach_tg_pt_gp(struct se_lun *lun,
1847                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1848 {
1849         spin_lock(&lun->lun_tg_pt_gp_lock);
1850         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1851         spin_unlock(&lun->lun_tg_pt_gp_lock);
1852 }
1853
1854 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1855                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1856 {
1857         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1858
1859         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1860         list_del_init(&lun->lun_tg_pt_gp_link);
1861         tg_pt_gp->tg_pt_gp_members--;
1862         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1863
1864         lun->lun_tg_pt_gp = NULL;
1865 }
1866
1867 void target_detach_tg_pt_gp(struct se_lun *lun)
1868 {
1869         struct t10_alua_tg_pt_gp *tg_pt_gp;
1870
1871         spin_lock(&lun->lun_tg_pt_gp_lock);
1872         tg_pt_gp = lun->lun_tg_pt_gp;
1873         if (tg_pt_gp)
1874                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1875         spin_unlock(&lun->lun_tg_pt_gp_lock);
1876 }
1877
1878 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1879 {
1880         struct config_item *tg_pt_ci;
1881         struct t10_alua_tg_pt_gp *tg_pt_gp;
1882         ssize_t len = 0;
1883
1884         spin_lock(&lun->lun_tg_pt_gp_lock);
1885         tg_pt_gp = lun->lun_tg_pt_gp;
1886         if (tg_pt_gp) {
1887                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1888                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1889                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1890                         "Primary Access Status: %s\nTG Port Secondary Access"
1891                         " State: %s\nTG Port Secondary Access Status: %s\n",
1892                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1893                         core_alua_dump_state(
1894                                 tg_pt_gp->tg_pt_gp_alua_access_state),
1895                         core_alua_dump_status(
1896                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1897                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1898                         "Offline" : "None",
1899                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1900         }
1901         spin_unlock(&lun->lun_tg_pt_gp_lock);
1902
1903         return len;
1904 }
1905
1906 ssize_t core_alua_store_tg_pt_gp_info(
1907         struct se_lun *lun,
1908         const char *page,
1909         size_t count)
1910 {
1911         struct se_portal_group *tpg = lun->lun_tpg;
1912         /*
1913          * rcu_dereference_raw protected by se_lun->lun_group symlink
1914          * reference to se_device->dev_group.
1915          */
1916         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1917         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1918         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1919         int move = 0;
1920
1921         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1922             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1923                 return -ENODEV;
1924
1925         if (count > TG_PT_GROUP_NAME_BUF) {
1926                 pr_err("ALUA Target Port Group alias too large!\n");
1927                 return -EINVAL;
1928         }
1929         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1930         memcpy(buf, page, count);
1931         /*
1932          * Any ALUA target port group alias besides "NULL" means we will be
1933          * making a new group association.
1934          */
1935         if (strcmp(strstrip(buf), "NULL")) {
1936                 /*
1937                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1938                  * struct t10_alua_tg_pt_gp.  This reference is released with
1939                  * core_alua_put_tg_pt_gp_from_name() below.
1940                  */
1941                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1942                                         strstrip(buf));
1943                 if (!tg_pt_gp_new)
1944                         return -ENODEV;
1945         }
1946
1947         spin_lock(&lun->lun_tg_pt_gp_lock);
1948         tg_pt_gp = lun->lun_tg_pt_gp;
1949         if (tg_pt_gp) {
1950                 /*
1951                  * Clearing an existing tg_pt_gp association, and replacing
1952                  * with the default_tg_pt_gp.
1953                  */
1954                 if (!tg_pt_gp_new) {
1955                         pr_debug("Target_Core_ConfigFS: Moving"
1956                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1957                                 " alua/%s, ID: %hu back to"
1958                                 " default_tg_pt_gp\n",
1959                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1960                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1961                                 config_item_name(&lun->lun_group.cg_item),
1962                                 config_item_name(
1963                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1964                                 tg_pt_gp->tg_pt_gp_id);
1965
1966                         __target_detach_tg_pt_gp(lun, tg_pt_gp);
1967                         __target_attach_tg_pt_gp(lun,
1968                                         dev->t10_alua.default_tg_pt_gp);
1969                         spin_unlock(&lun->lun_tg_pt_gp_lock);
1970
1971                         return count;
1972                 }
1973                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1974                 move = 1;
1975         }
1976
1977         __target_attach_tg_pt_gp(lun, tg_pt_gp_new);
1978         spin_unlock(&lun->lun_tg_pt_gp_lock);
1979         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1980                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1981                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1982                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1983                 config_item_name(&lun->lun_group.cg_item),
1984                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1985                 tg_pt_gp_new->tg_pt_gp_id);
1986
1987         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1988         return count;
1989 }
1990
1991 ssize_t core_alua_show_access_type(
1992         struct t10_alua_tg_pt_gp *tg_pt_gp,
1993         char *page)
1994 {
1995         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
1996             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
1997                 return sprintf(page, "Implicit and Explicit\n");
1998         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
1999                 return sprintf(page, "Implicit\n");
2000         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2001                 return sprintf(page, "Explicit\n");
2002         else
2003                 return sprintf(page, "None\n");
2004 }
2005
2006 ssize_t core_alua_store_access_type(
2007         struct t10_alua_tg_pt_gp *tg_pt_gp,
2008         const char *page,
2009         size_t count)
2010 {
2011         unsigned long tmp;
2012         int ret;
2013
2014         ret = kstrtoul(page, 0, &tmp);
2015         if (ret < 0) {
2016                 pr_err("Unable to extract alua_access_type\n");
2017                 return ret;
2018         }
2019         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2020                 pr_err("Illegal value for alua_access_type:"
2021                                 " %lu\n", tmp);
2022                 return -EINVAL;
2023         }
2024         if (tmp == 3)
2025                 tg_pt_gp->tg_pt_gp_alua_access_type =
2026                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2027         else if (tmp == 2)
2028                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2029         else if (tmp == 1)
2030                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2031         else
2032                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2033
2034         return count;
2035 }
2036
2037 ssize_t core_alua_show_nonop_delay_msecs(
2038         struct t10_alua_tg_pt_gp *tg_pt_gp,
2039         char *page)
2040 {
2041         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2042 }
2043
2044 ssize_t core_alua_store_nonop_delay_msecs(
2045         struct t10_alua_tg_pt_gp *tg_pt_gp,
2046         const char *page,
2047         size_t count)
2048 {
2049         unsigned long tmp;
2050         int ret;
2051
2052         ret = kstrtoul(page, 0, &tmp);
2053         if (ret < 0) {
2054                 pr_err("Unable to extract nonop_delay_msecs\n");
2055                 return ret;
2056         }
2057         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2058                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2059                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2060                         ALUA_MAX_NONOP_DELAY_MSECS);
2061                 return -EINVAL;
2062         }
2063         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2064
2065         return count;
2066 }
2067
2068 ssize_t core_alua_show_trans_delay_msecs(
2069         struct t10_alua_tg_pt_gp *tg_pt_gp,
2070         char *page)
2071 {
2072         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2073 }
2074
2075 ssize_t core_alua_store_trans_delay_msecs(
2076         struct t10_alua_tg_pt_gp *tg_pt_gp,
2077         const char *page,
2078         size_t count)
2079 {
2080         unsigned long tmp;
2081         int ret;
2082
2083         ret = kstrtoul(page, 0, &tmp);
2084         if (ret < 0) {
2085                 pr_err("Unable to extract trans_delay_msecs\n");
2086                 return ret;
2087         }
2088         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2089                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2090                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2091                         ALUA_MAX_TRANS_DELAY_MSECS);
2092                 return -EINVAL;
2093         }
2094         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2095
2096         return count;
2097 }
2098
2099 ssize_t core_alua_show_implicit_trans_secs(
2100         struct t10_alua_tg_pt_gp *tg_pt_gp,
2101         char *page)
2102 {
2103         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2104 }
2105
2106 ssize_t core_alua_store_implicit_trans_secs(
2107         struct t10_alua_tg_pt_gp *tg_pt_gp,
2108         const char *page,
2109         size_t count)
2110 {
2111         unsigned long tmp;
2112         int ret;
2113
2114         ret = kstrtoul(page, 0, &tmp);
2115         if (ret < 0) {
2116                 pr_err("Unable to extract implicit_trans_secs\n");
2117                 return ret;
2118         }
2119         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2120                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2121                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2122                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2123                 return  -EINVAL;
2124         }
2125         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2126
2127         return count;
2128 }
2129
2130 ssize_t core_alua_show_preferred_bit(
2131         struct t10_alua_tg_pt_gp *tg_pt_gp,
2132         char *page)
2133 {
2134         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2135 }
2136
2137 ssize_t core_alua_store_preferred_bit(
2138         struct t10_alua_tg_pt_gp *tg_pt_gp,
2139         const char *page,
2140         size_t count)
2141 {
2142         unsigned long tmp;
2143         int ret;
2144
2145         ret = kstrtoul(page, 0, &tmp);
2146         if (ret < 0) {
2147                 pr_err("Unable to extract preferred ALUA value\n");
2148                 return ret;
2149         }
2150         if ((tmp != 0) && (tmp != 1)) {
2151                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2152                 return -EINVAL;
2153         }
2154         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2155
2156         return count;
2157 }
2158
2159 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2160 {
2161         return sprintf(page, "%d\n",
2162                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2163 }
2164
2165 ssize_t core_alua_store_offline_bit(
2166         struct se_lun *lun,
2167         const char *page,
2168         size_t count)
2169 {
2170         /*
2171          * rcu_dereference_raw protected by se_lun->lun_group symlink
2172          * reference to se_device->dev_group.
2173          */
2174         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2175         unsigned long tmp;
2176         int ret;
2177
2178         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2179             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2180                 return -ENODEV;
2181
2182         ret = kstrtoul(page, 0, &tmp);
2183         if (ret < 0) {
2184                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2185                 return ret;
2186         }
2187         if ((tmp != 0) && (tmp != 1)) {
2188                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2189                                 tmp);
2190                 return -EINVAL;
2191         }
2192
2193         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2194         if (ret < 0)
2195                 return -EINVAL;
2196
2197         return count;
2198 }
2199
2200 ssize_t core_alua_show_secondary_status(
2201         struct se_lun *lun,
2202         char *page)
2203 {
2204         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2205 }
2206
2207 ssize_t core_alua_store_secondary_status(
2208         struct se_lun *lun,
2209         const char *page,
2210         size_t count)
2211 {
2212         unsigned long tmp;
2213         int ret;
2214
2215         ret = kstrtoul(page, 0, &tmp);
2216         if (ret < 0) {
2217                 pr_err("Unable to extract alua_tg_pt_status\n");
2218                 return ret;
2219         }
2220         if ((tmp != ALUA_STATUS_NONE) &&
2221             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2222             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2223                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2224                                 tmp);
2225                 return -EINVAL;
2226         }
2227         lun->lun_tg_pt_secondary_stat = (int)tmp;
2228
2229         return count;
2230 }
2231
2232 ssize_t core_alua_show_secondary_write_metadata(
2233         struct se_lun *lun,
2234         char *page)
2235 {
2236         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2237 }
2238
2239 ssize_t core_alua_store_secondary_write_metadata(
2240         struct se_lun *lun,
2241         const char *page,
2242         size_t count)
2243 {
2244         unsigned long tmp;
2245         int ret;
2246
2247         ret = kstrtoul(page, 0, &tmp);
2248         if (ret < 0) {
2249                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2250                 return ret;
2251         }
2252         if ((tmp != 0) && (tmp != 1)) {
2253                 pr_err("Illegal value for alua_tg_pt_write_md:"
2254                                 " %lu\n", tmp);
2255                 return -EINVAL;
2256         }
2257         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2258
2259         return count;
2260 }
2261
2262 int core_setup_alua(struct se_device *dev)
2263 {
2264         if (!(dev->transport_flags &
2265              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2266             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2267                 struct t10_alua_lu_gp_member *lu_gp_mem;
2268
2269                 /*
2270                  * Associate this struct se_device with the default ALUA
2271                  * LUN Group.
2272                  */
2273                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2274                 if (IS_ERR(lu_gp_mem))
2275                         return PTR_ERR(lu_gp_mem);
2276
2277                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2278                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2279                                 default_lu_gp);
2280                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2281
2282                 pr_debug("%s: Adding to default ALUA LU Group:"
2283                         " core/alua/lu_gps/default_lu_gp\n",
2284                         dev->transport->name);
2285         }
2286
2287         return 0;
2288 }