drivers/target/target_core_alua.c

   1 /*******************************************************************************
   2  * Filename:  target_core_alua.c
   3  *
   4  * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
   5  *
   6  * (c) Copyright 2009-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <[email protected]>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/slab.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/configfs.h>
  29 #include <linux/delay.h>
  30 #include <linux/export.h>
  31 #include <linux/fcntl.h>
  32 #include <linux/file.h>
  33 #include <linux/fs.h>
  34 #include <scsi/scsi_proto.h>
  35 #include <asm/unaligned.h>
  36
  37 #include <target/target_core_base.h>
  38 #include <target/target_core_backend.h>
  39 #include <target/target_core_fabric.h>
  40
  41 #include "target_core_internal.h"
  42 #include "target_core_alua.h"
  43 #include "target_core_ua.h"
  44
  45 static sense_reason_t core_alua_check_transition(int state, int valid,
  46                                                  int *primary, int explicit);
  47 static int core_alua_set_tg_pt_secondary_state(
  48                 struct se_lun *lun, int explicit, int offline);
  49
  50 static char *core_alua_dump_state(int state);
  51
  52 static void __target_attach_tg_pt_gp(struct se_lun *lun,
  53                 struct t10_alua_tg_pt_gp *tg_pt_gp);
  54
  55 static u16 alua_lu_gps_counter;
  56 static u32 alua_lu_gps_count;
  57
  58 static DEFINE_SPINLOCK(lu_gps_lock);
  59 static LIST_HEAD(lu_gps_list);
  60
  61 struct t10_alua_lu_gp *default_lu_gp;
  62
  63 /*
  64  * REPORT REFERRALS
  65  *
  66  * See sbc3r35 section 5.23
  67  */
  68 sense_reason_t
  69 target_emulate_report_referrals(struct se_cmd *cmd)
  70 {
  71         struct se_device *dev = cmd->se_dev;
  72         struct t10_alua_lba_map *map;
  73         struct t10_alua_lba_map_member *map_mem;
  74         unsigned char *buf;
  75         u32 rd_len = 0, off;
  76
  77         if (cmd->data_length < 4) {
  78                 pr_warn("REPORT REFERRALS allocation length %u too"
  79                         " small\n", cmd->data_length);
  80                 return TCM_INVALID_CDB_FIELD;
  81         }
  82
  83         buf = transport_kmap_data_sg(cmd);
  84         if (!buf)
  85                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
  86
  87         off = 4;
  88         spin_lock(&dev->t10_alua.lba_map_lock);
  89         if (list_empty(&dev->t10_alua.lba_map_list)) {
  90                 spin_unlock(&dev->t10_alua.lba_map_lock);
  91                 transport_kunmap_data_sg(cmd);
  92
  93                 return TCM_UNSUPPORTED_SCSI_OPCODE;
  94         }
  95
  96         list_for_each_entry(map, &dev->t10_alua.lba_map_list,
  97                             lba_map_list) {
  98                 int desc_num = off + 3;
  99                 int pg_num;
 100
 101                 off += 4;
 102                 if (cmd->data_length > off)
 103                         put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
 104                 off += 8;
 105                 if (cmd->data_length > off)
 106                         put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
 107                 off += 8;
 108                 rd_len += 20;
 109                 pg_num = 0;
 110                 list_for_each_entry(map_mem, &map->lba_map_mem_list,
 111                                     lba_map_mem_list) {
 112                         int alua_state = map_mem->lba_map_mem_alua_state;
 113                         int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
 114
 115                         if (cmd->data_length > off)
 116                                 buf[off] = alua_state & 0x0f;
 117                         off += 2;
 118                         if (cmd->data_length > off)
 119                                 buf[off] = (alua_pg_id >> 8) & 0xff;
 120                         off++;
 121                         if (cmd->data_length > off)
 122                                 buf[off] = (alua_pg_id & 0xff);
 123                         off++;
 124                         rd_len += 4;
 125                         pg_num++;
 126                 }
 127                 if (cmd->data_length > desc_num)
 128                         buf[desc_num] = pg_num;
 129         }
 130         spin_unlock(&dev->t10_alua.lba_map_lock);
 131
 132         /*
 133          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 134          */
 135         put_unaligned_be16(rd_len, &buf[2]);
 136
 137         transport_kunmap_data_sg(cmd);
 138
 139         target_complete_cmd(cmd, GOOD);
 140         return 0;
 141 }
 142
 143 /*
 144  * REPORT_TARGET_PORT_GROUPS
 145  *
 146  * See spc4r17 section 6.27
 147  */
 148 sense_reason_t
 149 target_emulate_report_target_port_groups(struct se_cmd *cmd)
 150 {
 151         struct se_device *dev = cmd->se_dev;
 152         struct t10_alua_tg_pt_gp *tg_pt_gp;
 153         struct se_lun *lun;
 154         unsigned char *buf;
 155         u32 rd_len = 0, off;
 156         int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
 157
 158         /*
 159          * Skip over RESERVED area to first Target port group descriptor
 160          * depending on the PARAMETER DATA FORMAT type..
 161          */
 162         if (ext_hdr != 0)
 163                 off = 8;
 164         else
 165                 off = 4;
 166
 167         if (cmd->data_length < off) {
 168                 pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
 169                         " small for %s header\n", cmd->data_length,
 170                         (ext_hdr) ? "extended" : "normal");
 171                 return TCM_INVALID_CDB_FIELD;
 172         }
 173         buf = transport_kmap_data_sg(cmd);
 174         if (!buf)
 175                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 176
 177         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 178         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
 179                         tg_pt_gp_list) {
 180                 /*
 181                  * Check if the Target port group and Target port descriptor list
 182                  * based on tg_pt_gp_members count will fit into the response payload.
 183                  * Otherwise, bump rd_len to let the initiator know we have exceeded
 184                  * the allocation length and the response is truncated.
 185                  */
 186                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
 187                      cmd->data_length) {
 188                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
 189                         continue;
 190                 }
 191                 /*
 192                  * PREF: Preferred target port bit, determine if this
 193                  * bit should be set for port group.
 194                  */
 195                 if (tg_pt_gp->tg_pt_gp_pref)
 196                         buf[off] = 0x80;
 197                 /*
 198                  * Set the ASYMMETRIC ACCESS State
 199                  */
 200                 buf[off++] |= (atomic_read(
 201                         &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
 202                 /*
 203                  * Set supported ASYMMETRIC ACCESS State bits
 204                  */
 205                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
 206                 /*
 207                  * TARGET PORT GROUP
 208                  */
 209                 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
 210                 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
 211
 212                 off++; /* Skip over Reserved */
 213                 /*
 214                  * STATUS CODE
 215                  */
 216                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 217                 /*
 218                  * Vendor Specific field
 219                  */
 220                 buf[off++] = 0x00;
 221                 /*
 222                  * TARGET PORT COUNT
 223                  */
 224                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 225                 rd_len += 8;
 226
 227                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 228                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 229                                 lun_tg_pt_gp_link) {
 230                         /*
 231                          * Start Target Port descriptor format
 232                          *
 233                          * See spc4r17 section 6.2.7 Table 247
 234                          */
 235                         off += 2; /* Skip over Obsolete */
 236                         /*
 237                          * Set RELATIVE TARGET PORT IDENTIFIER
 238                          */
 239                         buf[off++] = ((lun->lun_rtpi >> 8) & 0xff);
 240                         buf[off++] = (lun->lun_rtpi & 0xff);
 241                         rd_len += 4;
 242                 }
 243                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 244         }
 245         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 246         /*
 247          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 248          */
 249         put_unaligned_be32(rd_len, &buf[0]);
 250
 251         /*
 252          * Fill in the Extended header parameter data format if requested
 253          */
 254         if (ext_hdr != 0) {
 255                 buf[4] = 0x10;
 256                 /*
 257                  * Set the implicit transition time (in seconds) for the application
 258                  * client to use as a base for it's transition timeout value.
 259                  *
 260                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
 261                  * this CDB was received upon to determine this value individually
 262                  * for ALUA target port group.
 263                  */
 264                 spin_lock(&cmd->se_lun->lun_tg_pt_gp_lock);
 265                 tg_pt_gp = cmd->se_lun->lun_tg_pt_gp;
 266                 if (tg_pt_gp)
 267                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
 268                 spin_unlock(&cmd->se_lun->lun_tg_pt_gp_lock);
 269         }
 270         transport_kunmap_data_sg(cmd);
 271
 272         target_complete_cmd(cmd, GOOD);
 273         return 0;
 274 }
 275
 276 /*
 277  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
 278  *
 279  * See spc4r17 section 6.35
 280  */
 281 sense_reason_t
 282 target_emulate_set_target_port_groups(struct se_cmd *cmd)
 283 {
 284         struct se_device *dev = cmd->se_dev;
 285         struct se_lun *l_lun = cmd->se_lun;
 286         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 287         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 288         unsigned char *buf;
 289         unsigned char *ptr;
 290         sense_reason_t rc = TCM_NO_SENSE;
 291         u32 len = 4; /* Skip over RESERVED area in header */
 292         int alua_access_state, primary = 0, valid_states;
 293         u16 tg_pt_id, rtpi;
 294
 295         if (cmd->data_length < 4) {
 296                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
 297                         " small\n", cmd->data_length);
 298                 return TCM_INVALID_PARAMETER_LIST;
 299         }
 300
 301         buf = transport_kmap_data_sg(cmd);
 302         if (!buf)
 303                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 304
 305         /*
 306          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
 307          * for the local tg_pt_gp.
 308          */
 309         spin_lock(&l_lun->lun_tg_pt_gp_lock);
 310         l_tg_pt_gp = l_lun->lun_tg_pt_gp;
 311         if (!l_tg_pt_gp) {
 312                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 313                 pr_err("Unable to access l_lun->tg_pt_gp\n");
 314                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 315                 goto out;
 316         }
 317
 318         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
 319                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 320                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 321                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
 322                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 323                 goto out;
 324         }
 325         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
 326         spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 327
 328         ptr = &buf[4]; /* Skip over RESERVED area in header */
 329
 330         while (len < cmd->data_length) {
 331                 bool found = false;
 332                 alua_access_state = (ptr[0] & 0x0f);
 333                 /*
 334                  * Check the received ALUA access state, and determine if
 335                  * the state is a primary or secondary target port asymmetric
 336                  * access state.
 337                  */
 338                 rc = core_alua_check_transition(alua_access_state, valid_states,
 339                                                 &primary, 1);
 340                 if (rc) {
 341                         /*
 342                          * If the SET TARGET PORT GROUPS attempts to establish
 343                          * an invalid combination of target port asymmetric
 344                          * access states or attempts to establish an
 345                          * unsupported target port asymmetric access state,
 346                          * then the command shall be terminated with CHECK
 347                          * CONDITION status, with the sense key set to ILLEGAL
 348                          * REQUEST, and the additional sense code set to INVALID
 349                          * FIELD IN PARAMETER LIST.
 350                          */
 351                         goto out;
 352                 }
 353
 354                 /*
 355                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 356                  * specifies a primary target port asymmetric access state,
 357                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 358                  * a primary target port group for which the primary target
 359                  * port asymmetric access state shall be changed. If the
 360                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 361                  * port asymmetric access state, then the TARGET PORT GROUP OR
 362                  * TARGET PORT field specifies the relative target port
 363                  * identifier (see 3.1.120) of the target port for which the
 364                  * secondary target port asymmetric access state shall be
 365                  * changed.
 366                  */
 367                 if (primary) {
 368                         tg_pt_id = get_unaligned_be16(ptr + 2);
 369                         /*
 370                          * Locate the matching target port group ID from
 371                          * the global tg_pt_gp list
 372                          */
 373                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 374                         list_for_each_entry(tg_pt_gp,
 375                                         &dev->t10_alua.tg_pt_gps_list,
 376                                         tg_pt_gp_list) {
 377                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 378                                         continue;
 379
 380                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 381                                         continue;
 382
 383                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 384
 385                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 386
 387                                 if (!core_alua_do_port_transition(tg_pt_gp,
 388                                                 dev, l_lun, nacl,
 389                                                 alua_access_state, 1))
 390                                         found = true;
 391
 392                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 393                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 394                                 break;
 395                         }
 396                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 397                 } else {
 398                         struct se_lun *lun;
 399
 400                         /*
 401                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
 402                          * the Target Port in question for the the incoming
 403                          * SET_TARGET_PORT_GROUPS op.
 404                          */
 405                         rtpi = get_unaligned_be16(ptr + 2);
 406                         /*
 407                          * Locate the matching relative target port identifier
 408                          * for the struct se_device storage object.
 409                          */
 410                         spin_lock(&dev->se_port_lock);
 411                         list_for_each_entry(lun, &dev->dev_sep_list,
 412                                                         lun_dev_link) {
 413                                 if (lun->lun_rtpi != rtpi)
 414                                         continue;
 415
 416                                 // XXX: racy unlock
 417                                 spin_unlock(&dev->se_port_lock);
 418
 419                                 if (!core_alua_set_tg_pt_secondary_state(
 420                                                 lun, 1, 1))
 421                                         found = true;
 422
 423                                 spin_lock(&dev->se_port_lock);
 424                                 break;
 425                         }
 426                         spin_unlock(&dev->se_port_lock);
 427                 }
 428
 429                 if (!found) {
 430                         rc = TCM_INVALID_PARAMETER_LIST;
 431                         goto out;
 432                 }
 433
 434                 ptr += 4;
 435                 len += 4;
 436         }
 437
 438 out:
 439         transport_kunmap_data_sg(cmd);
 440         if (!rc)
 441                 target_complete_cmd(cmd, GOOD);
 442         return rc;
 443 }
 444
 445 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
 446 {
 447         /*
 448          * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
 449          * The ALUA additional sense code qualifier (ASCQ) is determined
 450          * by the ALUA primary or secondary access state..
 451          */
 452         pr_debug("[%s]: ALUA TG Port not available, "
 453                 "SenseKey: NOT_READY, ASC/ASCQ: "
 454                 "0x04/0x%02x\n",
 455                 cmd->se_tfo->get_fabric_name(), alua_ascq);
 456
 457         cmd->scsi_asc = 0x04;
 458         cmd->scsi_ascq = alua_ascq;
 459 }
 460
 461 static inline void core_alua_state_nonoptimized(
 462         struct se_cmd *cmd,
 463         unsigned char *cdb,
 464         int nonop_delay_msecs)
 465 {
 466         /*
 467          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 468          * later to determine if processing of this cmd needs to be
 469          * temporarily delayed for the Active/NonOptimized primary access state.
 470          */
 471         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 472         cmd->alua_nonop_delay = nonop_delay_msecs;
 473 }
 474
 475 static inline int core_alua_state_lba_dependent(
 476         struct se_cmd *cmd,
 477         struct t10_alua_tg_pt_gp *tg_pt_gp)
 478 {
 479         struct se_device *dev = cmd->se_dev;
 480         u64 segment_size, segment_mult, sectors, lba;
 481
 482         /* Only need to check for cdb actually containing LBAs */
 483         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
 484                 return 0;
 485
 486         spin_lock(&dev->t10_alua.lba_map_lock);
 487         segment_size = dev->t10_alua.lba_map_segment_size;
 488         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
 489         sectors = cmd->data_length / dev->dev_attrib.block_size;
 490
 491         lba = cmd->t_task_lba;
 492         while (lba < cmd->t_task_lba + sectors) {
 493                 struct t10_alua_lba_map *cur_map = NULL, *map;
 494                 struct t10_alua_lba_map_member *map_mem;
 495
 496                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
 497                                     lba_map_list) {
 498                         u64 start_lba, last_lba;
 499                         u64 first_lba = map->lba_map_first_lba;
 500
 501                         if (segment_mult) {
 502                                 u64 tmp = lba;
 503                                 start_lba = do_div(tmp, segment_size * segment_mult);
 504
 505                                 last_lba = first_lba + segment_size - 1;
 506                                 if (start_lba >= first_lba &&
 507                                     start_lba <= last_lba) {
 508                                         lba += segment_size;
 509                                         cur_map = map;
 510                                         break;
 511                                 }
 512                         } else {
 513                                 last_lba = map->lba_map_last_lba;
 514                                 if (lba >= first_lba && lba <= last_lba) {
 515                                         lba = last_lba + 1;
 516                                         cur_map = map;
 517                                         break;
 518                                 }
 519                         }
 520                 }
 521                 if (!cur_map) {
 522                         spin_unlock(&dev->t10_alua.lba_map_lock);
 523                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 524                         return 1;
 525                 }
 526                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
 527                                     lba_map_mem_list) {
 528                         if (map_mem->lba_map_mem_alua_pg_id !=
 529                             tg_pt_gp->tg_pt_gp_id)
 530                                 continue;
 531                         switch(map_mem->lba_map_mem_alua_state) {
 532                         case ALUA_ACCESS_STATE_STANDBY:
 533                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 534                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 535                                 return 1;
 536                         case ALUA_ACCESS_STATE_UNAVAILABLE:
 537                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 538                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 539                                 return 1;
 540                         default:
 541                                 break;
 542                         }
 543                 }
 544         }
 545         spin_unlock(&dev->t10_alua.lba_map_lock);
 546         return 0;
 547 }
 548
 549 static inline int core_alua_state_standby(
 550         struct se_cmd *cmd,
 551         unsigned char *cdb)
 552 {
 553         /*
 554          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 555          * spc4r17 section 5.9.2.4.4
 556          */
 557         switch (cdb[0]) {
 558         case INQUIRY:
 559         case LOG_SELECT:
 560         case LOG_SENSE:
 561         case MODE_SELECT:
 562         case MODE_SENSE:
 563         case REPORT_LUNS:
 564         case RECEIVE_DIAGNOSTIC:
 565         case SEND_DIAGNOSTIC:
 566         case READ_CAPACITY:
 567                 return 0;
 568         case SERVICE_ACTION_IN_16:
 569                 switch (cdb[1] & 0x1f) {
 570                 case SAI_READ_CAPACITY_16:
 571                         return 0;
 572                 default:
 573                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 574                         return 1;
 575                 }
 576         case MAINTENANCE_IN:
 577                 switch (cdb[1] & 0x1f) {
 578                 case MI_REPORT_TARGET_PGS:
 579                         return 0;
 580                 default:
 581                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 582                         return 1;
 583                 }
 584         case MAINTENANCE_OUT:
 585                 switch (cdb[1]) {
 586                 case MO_SET_TARGET_PGS:
 587                         return 0;
 588                 default:
 589                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 590                         return 1;
 591                 }
 592         case REQUEST_SENSE:
 593         case PERSISTENT_RESERVE_IN:
 594         case PERSISTENT_RESERVE_OUT:
 595         case READ_BUFFER:
 596         case WRITE_BUFFER:
 597                 return 0;
 598         default:
 599                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 600                 return 1;
 601         }
 602
 603         return 0;
 604 }
 605
 606 static inline int core_alua_state_unavailable(
 607         struct se_cmd *cmd,
 608         unsigned char *cdb)
 609 {
 610         /*
 611          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 612          * spc4r17 section 5.9.2.4.5
 613          */
 614         switch (cdb[0]) {
 615         case INQUIRY:
 616         case REPORT_LUNS:
 617                 return 0;
 618         case MAINTENANCE_IN:
 619                 switch (cdb[1] & 0x1f) {
 620                 case MI_REPORT_TARGET_PGS:
 621                         return 0;
 622                 default:
 623                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 624                         return 1;
 625                 }
 626         case MAINTENANCE_OUT:
 627                 switch (cdb[1]) {
 628                 case MO_SET_TARGET_PGS:
 629                         return 0;
 630                 default:
 631                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 632                         return 1;
 633                 }
 634         case REQUEST_SENSE:
 635         case READ_BUFFER:
 636         case WRITE_BUFFER:
 637                 return 0;
 638         default:
 639                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 640                 return 1;
 641         }
 642
 643         return 0;
 644 }
 645
 646 static inline int core_alua_state_transition(
 647         struct se_cmd *cmd,
 648         unsigned char *cdb)
 649 {
 650         /*
 651          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
 652          * spc4r17 section 5.9.2.5
 653          */
 654         switch (cdb[0]) {
 655         case INQUIRY:
 656         case REPORT_LUNS:
 657                 return 0;
 658         case MAINTENANCE_IN:
 659                 switch (cdb[1] & 0x1f) {
 660                 case MI_REPORT_TARGET_PGS:
 661                         return 0;
 662                 default:
 663                         set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 664                         return 1;
 665                 }
 666         case REQUEST_SENSE:
 667         case READ_BUFFER:
 668         case WRITE_BUFFER:
 669                 return 0;
 670         default:
 671                 set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 672                 return 1;
 673         }
 674
 675         return 0;
 676 }
 677
 678 /*
 679  * return 1: Is used to signal LUN not accessible, and check condition/not ready
 680  * return 0: Used to signal success
 681  * return -1: Used to signal failure, and invalid cdb field
 682  */
 683 sense_reason_t
 684 target_alua_state_check(struct se_cmd *cmd)
 685 {
 686         struct se_device *dev = cmd->se_dev;
 687         unsigned char *cdb = cmd->t_task_cdb;
 688         struct se_lun *lun = cmd->se_lun;
 689         struct t10_alua_tg_pt_gp *tg_pt_gp;
 690         int out_alua_state, nonop_delay_msecs;
 691
 692         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
 693                 return 0;
 694         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
 695                 return 0;
 696
 697         /*
 698          * First, check for a struct se_port specific secondary ALUA target port
 699          * access state: OFFLINE
 700          */
 701         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
 702                 pr_debug("ALUA: Got secondary offline status for local"
 703                                 " target port\n");
 704                 set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
 705                 return TCM_CHECK_CONDITION_NOT_READY;
 706         }
 707
 708         if (!lun->lun_tg_pt_gp)
 709                 return 0;
 710
 711         spin_lock(&lun->lun_tg_pt_gp_lock);
 712         tg_pt_gp = lun->lun_tg_pt_gp;
 713         out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 714         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 715
 716         // XXX: keeps using tg_pt_gp witout reference after unlock
 717         spin_unlock(&lun->lun_tg_pt_gp_lock);
 718         /*
 719          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
 720          * statement so the compiler knows explicitly to check this case first.
 721          * For the Optimized ALUA access state case, we want to process the
 722          * incoming fabric cmd ASAP..
 723          */
 724         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
 725                 return 0;
 726
 727         switch (out_alua_state) {
 728         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 729                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
 730                 break;
 731         case ALUA_ACCESS_STATE_STANDBY:
 732                 if (core_alua_state_standby(cmd, cdb))
 733                         return TCM_CHECK_CONDITION_NOT_READY;
 734                 break;
 735         case ALUA_ACCESS_STATE_UNAVAILABLE:
 736                 if (core_alua_state_unavailable(cmd, cdb))
 737                         return TCM_CHECK_CONDITION_NOT_READY;
 738                 break;
 739         case ALUA_ACCESS_STATE_TRANSITION:
 740                 if (core_alua_state_transition(cmd, cdb))
 741                         return TCM_CHECK_CONDITION_NOT_READY;
 742                 break;
 743         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 744                 if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
 745                         return TCM_CHECK_CONDITION_NOT_READY;
 746                 break;
 747         /*
 748          * OFFLINE is a secondary ALUA target port group access state, that is
 749          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
 750          */
 751         case ALUA_ACCESS_STATE_OFFLINE:
 752         default:
 753                 pr_err("Unknown ALUA access state: 0x%02x\n",
 754                                 out_alua_state);
 755                 return TCM_INVALID_CDB_FIELD;
 756         }
 757
 758         return 0;
 759 }
 760
 761 /*
 762  * Check implicit and explicit ALUA state change request.
 763  */
 764 static sense_reason_t
 765 core_alua_check_transition(int state, int valid, int *primary, int explicit)
 766 {
 767         /*
 768          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 769          * defined as primary target port asymmetric access states.
 770          */
 771         switch (state) {
 772         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 773                 if (!(valid & ALUA_AO_SUP))
 774                         goto not_supported;
 775                 *primary = 1;
 776                 break;
 777         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 778                 if (!(valid & ALUA_AN_SUP))
 779                         goto not_supported;
 780                 *primary = 1;
 781                 break;
 782         case ALUA_ACCESS_STATE_STANDBY:
 783                 if (!(valid & ALUA_S_SUP))
 784                         goto not_supported;
 785                 *primary = 1;
 786                 break;
 787         case ALUA_ACCESS_STATE_UNAVAILABLE:
 788                 if (!(valid & ALUA_U_SUP))
 789                         goto not_supported;
 790                 *primary = 1;
 791                 break;
 792         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 793                 if (!(valid & ALUA_LBD_SUP))
 794                         goto not_supported;
 795                 *primary = 1;
 796                 break;
 797         case ALUA_ACCESS_STATE_OFFLINE:
 798                 /*
 799                  * OFFLINE state is defined as a secondary target port
 800                  * asymmetric access state.
 801                  */
 802                 if (!(valid & ALUA_O_SUP))
 803                         goto not_supported;
 804                 *primary = 0;
 805                 break;
 806         case ALUA_ACCESS_STATE_TRANSITION:
 807                 if (!(valid & ALUA_T_SUP) || explicit)
 808                         /*
 809                          * Transitioning is set internally and by tcmu daemon,
 810                          * and cannot be selected through a STPG.
 811                          */
 812                         goto not_supported;
 813                 *primary = 0;
 814                 break;
 815         default:
 816                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 817                 return TCM_INVALID_PARAMETER_LIST;
 818         }
 819
 820         return 0;
 821
 822 not_supported:
 823         pr_err("ALUA access state %s not supported",
 824                core_alua_dump_state(state));
 825         return TCM_INVALID_PARAMETER_LIST;
 826 }
 827
 828 static char *core_alua_dump_state(int state)
 829 {
 830         switch (state) {
 831         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 832                 return "Active/Optimized";
 833         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 834                 return "Active/NonOptimized";
 835         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 836                 return "LBA Dependent";
 837         case ALUA_ACCESS_STATE_STANDBY:
 838                 return "Standby";
 839         case ALUA_ACCESS_STATE_UNAVAILABLE:
 840                 return "Unavailable";
 841         case ALUA_ACCESS_STATE_OFFLINE:
 842                 return "Offline";
 843         case ALUA_ACCESS_STATE_TRANSITION:
 844                 return "Transitioning";
 845         default:
 846                 return "Unknown";
 847         }
 848
 849         return NULL;
 850 }
 851
 852 char *core_alua_dump_status(int status)
 853 {
 854         switch (status) {
 855         case ALUA_STATUS_NONE:
 856                 return "None";
 857         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
 858                 return "Altered by Explicit STPG";
 859         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
 860                 return "Altered by Implicit ALUA";
 861         default:
 862                 return "Unknown";
 863         }
 864
 865         return NULL;
 866 }
 867
 868 /*
 869  * Used by fabric modules to determine when we need to delay processing
 870  * for the Active/NonOptimized paths..
 871  */
 872 int core_alua_check_nonop_delay(
 873         struct se_cmd *cmd)
 874 {
 875         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 876                 return 0;
 877         if (in_interrupt())
 878                 return 0;
 879         /*
 880          * The ALUA Active/NonOptimized access state delay can be disabled
 881          * in via configfs with a value of zero
 882          */
 883         if (!cmd->alua_nonop_delay)
 884                 return 0;
 885         /*
 886          * struct se_cmd->alua_nonop_delay gets set by a target port group
 887          * defined interval in core_alua_state_nonoptimized()
 888          */
 889         msleep_interruptible(cmd->alua_nonop_delay);
 890         return 0;
 891 }
 892 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 893
 894 static int core_alua_write_tpg_metadata(
 895         const char *path,
 896         unsigned char *md_buf,
 897         u32 md_buf_len)
 898 {
 899         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
 900         int ret;
 901
 902         if (IS_ERR(file)) {
 903                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
 904                 return -ENODEV;
 905         }
 906         ret = kernel_write(file, md_buf, md_buf_len, 0);
 907         if (ret < 0)
 908                 pr_err("Error writing ALUA metadata file: %s\n", path);
 909         fput(file);
 910         return (ret < 0) ? -EIO : 0;
 911 }
 912
 913 /*
 914  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
 915  */
 916 static int core_alua_update_tpg_primary_metadata(
 917         struct t10_alua_tg_pt_gp *tg_pt_gp)
 918 {
 919         unsigned char *md_buf;
 920         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
 921         char path[ALUA_METADATA_PATH_LEN];
 922         int len, rc;
 923
 924         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
 925         if (!md_buf) {
 926                 pr_err("Unable to allocate buf for ALUA metadata\n");
 927                 return -ENOMEM;
 928         }
 929
 930         memset(path, 0, ALUA_METADATA_PATH_LEN);
 931
 932         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
 933                         "tg_pt_gp_id=%hu\n"
 934                         "alua_access_state=0x%02x\n"
 935                         "alua_access_status=0x%02x\n",
 936                         tg_pt_gp->tg_pt_gp_id,
 937                         tg_pt_gp->tg_pt_gp_alua_pending_state,
 938                         tg_pt_gp->tg_pt_gp_alua_access_status);
 939
 940         snprintf(path, ALUA_METADATA_PATH_LEN,
 941                 "%s/alua/tpgs_%s/%s", db_root, &wwn->unit_serial[0],
 942                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 943
 944         rc = core_alua_write_tpg_metadata(path, md_buf, len);
 945         kfree(md_buf);
 946         return rc;
 947 }
 948
 949 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
 950 {
 951         struct se_dev_entry *se_deve;
 952         struct se_lun *lun;
 953         struct se_lun_acl *lacl;
 954
 955         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 956         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 957                                 lun_tg_pt_gp_link) {
 958                 /*
 959                  * After an implicit target port asymmetric access state
 960                  * change, a device server shall establish a unit attention
 961                  * condition for the initiator port associated with every I_T
 962                  * nexus with the additional sense code set to ASYMMETRIC
 963                  * ACCESS STATE CHANGED.
 964                  *
 965                  * After an explicit target port asymmetric access state
 966                  * change, a device server shall establish a unit attention
 967                  * condition with the additional sense code set to ASYMMETRIC
 968                  * ACCESS STATE CHANGED for the initiator port associated with
 969                  * every I_T nexus other than the I_T nexus on which the SET
 970                  * TARGET PORT GROUPS command
 971                  */
 972                 if (!percpu_ref_tryget_live(&lun->lun_ref))
 973                         continue;
 974                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 975
 976                 spin_lock(&lun->lun_deve_lock);
 977                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
 978                         lacl = rcu_dereference_check(se_deve->se_lun_acl,
 979                                         lockdep_is_held(&lun->lun_deve_lock));
 980
 981                         /*
 982                          * spc4r37 p.242:
 983                          * After an explicit target port asymmetric access
 984                          * state change, a device server shall establish a
 985                          * unit attention condition with the additional sense
 986                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
 987                          * the initiator port associated with every I_T nexus
 988                          * other than the I_T nexus on which the SET TARGET
 989                          * PORT GROUPS command was received.
 990                          */
 991                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
 992                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
 993                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
 994                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
 995                                 continue;
 996
 997                         /*
 998                          * se_deve->se_lun_acl pointer may be NULL for a
 999                          * entry created without explicit Node+MappedLUN ACLs
1000                          */
1001                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1002                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
1003                                 continue;
1004
1005                         core_scsi3_ua_allocate(se_deve, 0x2A,
1006                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1007                 }
1008                 spin_unlock(&lun->lun_deve_lock);
1009
1010                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1011                 percpu_ref_put(&lun->lun_ref);
1012         }
1013         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1014 }
1015
1016 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
1017 {
1018         struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
1019                 struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work);
1020         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1021         bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
1022                          ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
1023
1024         /*
1025          * Update the ALUA metadata buf that has been allocated in
1026          * core_alua_do_port_transition(), this metadata will be written
1027          * to struct file.
1028          *
1029          * Note that there is the case where we do not want to update the
1030          * metadata when the saved metadata is being parsed in userspace
1031          * when setting the existing port access state and access status.
1032          *
1033          * Also note that the failure to write out the ALUA metadata to
1034          * struct file does NOT affect the actual ALUA transition.
1035          */
1036         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1037                 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1038                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1039                 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1040         }
1041         /*
1042          * Set the current primary ALUA access state to the requested new state
1043          */
1044         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1045                    tg_pt_gp->tg_pt_gp_alua_pending_state);
1046
1047         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1048                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1049                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1050                 tg_pt_gp->tg_pt_gp_id,
1051                 core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1052                 core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1053
1054         core_alua_queue_state_change_ua(tg_pt_gp);
1055
1056         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1057         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1058         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1059
1060         if (tg_pt_gp->tg_pt_gp_transition_complete)
1061                 complete(tg_pt_gp->tg_pt_gp_transition_complete);
1062 }
1063
1064 static int core_alua_do_transition_tg_pt(
1065         struct t10_alua_tg_pt_gp *tg_pt_gp,
1066         int new_state,
1067         int explicit)
1068 {
1069         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1070         DECLARE_COMPLETION_ONSTACK(wait);
1071
1072         /* Nothing to be done here */
1073         if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1074                 return 0;
1075
1076         if (explicit && new_state == ALUA_ACCESS_STATE_TRANSITION)
1077                 return -EAGAIN;
1078
1079         /*
1080          * Flush any pending transitions
1081          */
1082         if (!explicit)
1083                 flush_work(&tg_pt_gp->tg_pt_gp_transition_work);
1084
1085         /*
1086          * Save the old primary ALUA access state, and set the current state
1087          * to ALUA_ACCESS_STATE_TRANSITION.
1088          */
1089         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1090                         ALUA_ACCESS_STATE_TRANSITION);
1091         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1092                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1093                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1094
1095         core_alua_queue_state_change_ua(tg_pt_gp);
1096
1097         if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1098                 return 0;
1099
1100         tg_pt_gp->tg_pt_gp_alua_previous_state =
1101                 atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1102         tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1103
1104         /*
1105          * Check for the optional ALUA primary state transition delay
1106          */
1107         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1108                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1109
1110         /*
1111          * Take a reference for workqueue item
1112          */
1113         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1114         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1115         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1116
1117         schedule_work(&tg_pt_gp->tg_pt_gp_transition_work);
1118         if (explicit) {
1119                 tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1120                 wait_for_completion(&wait);
1121                 tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1122         }
1123
1124         return 0;
1125 }
1126
1127 int core_alua_do_port_transition(
1128         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1129         struct se_device *l_dev,
1130         struct se_lun *l_lun,
1131         struct se_node_acl *l_nacl,
1132         int new_state,
1133         int explicit)
1134 {
1135         struct se_device *dev;
1136         struct t10_alua_lu_gp *lu_gp;
1137         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1138         struct t10_alua_tg_pt_gp *tg_pt_gp;
1139         int primary, valid_states, rc = 0;
1140
1141         if (l_dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
1142                 return -ENODEV;
1143
1144         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1145         if (core_alua_check_transition(new_state, valid_states, &primary,
1146                                        explicit) != 0)
1147                 return -EINVAL;
1148
1149         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1150         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1151         lu_gp = local_lu_gp_mem->lu_gp;
1152         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1153         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1154         /*
1155          * For storage objects that are members of the 'default_lu_gp',
1156          * we only do transition on the passed *l_tp_pt_gp, and not
1157          * on all of the matching target port groups IDs in default_lu_gp.
1158          */
1159         if (!lu_gp->lu_gp_id) {
1160                 /*
1161                  * core_alua_do_transition_tg_pt() will always return
1162                  * success.
1163                  */
1164                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1165                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1166                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1167                                                    new_state, explicit);
1168                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1169                 return rc;
1170         }
1171         /*
1172          * For all other LU groups aside from 'default_lu_gp', walk all of
1173          * the associated storage objects looking for a matching target port
1174          * group ID from the local target port group.
1175          */
1176         spin_lock(&lu_gp->lu_gp_lock);
1177         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1178                                 lu_gp_mem_list) {
1179
1180                 dev = lu_gp_mem->lu_gp_mem_dev;
1181                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1182                 spin_unlock(&lu_gp->lu_gp_lock);
1183
1184                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1185                 list_for_each_entry(tg_pt_gp,
1186                                 &dev->t10_alua.tg_pt_gps_list,
1187                                 tg_pt_gp_list) {
1188
1189                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1190                                 continue;
1191                         /*
1192                          * If the target behavior port asymmetric access state
1193                          * is changed for any target port group accessible via
1194                          * a logical unit within a LU group, the target port
1195                          * behavior group asymmetric access states for the same
1196                          * target port group accessible via other logical units
1197                          * in that LU group will also change.
1198                          */
1199                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1200                                 continue;
1201
1202                         if (l_tg_pt_gp == tg_pt_gp) {
1203                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1204                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1205                         } else {
1206                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1207                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1208                         }
1209                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1210                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1211                         /*
1212                          * core_alua_do_transition_tg_pt() will always return
1213                          * success.
1214                          */
1215                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1216                                         new_state, explicit);
1217
1218                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1219                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1220                         if (rc)
1221                                 break;
1222                 }
1223                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1224
1225                 spin_lock(&lu_gp->lu_gp_lock);
1226                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1227         }
1228         spin_unlock(&lu_gp->lu_gp_lock);
1229
1230         if (!rc) {
1231                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1232                          " Group IDs: %hu %s transition to primary state: %s\n",
1233                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1234                          l_tg_pt_gp->tg_pt_gp_id,
1235                          (explicit) ? "explicit" : "implicit",
1236                          core_alua_dump_state(new_state));
1237         }
1238
1239         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1240         return rc;
1241 }
1242
1243 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1244 {
1245         struct se_portal_group *se_tpg = lun->lun_tpg;
1246         unsigned char *md_buf;
1247         char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1248         int len, rc;
1249
1250         mutex_lock(&lun->lun_tg_pt_md_mutex);
1251
1252         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1253         if (!md_buf) {
1254                 pr_err("Unable to allocate buf for ALUA metadata\n");
1255                 rc = -ENOMEM;
1256                 goto out_unlock;
1257         }
1258
1259         memset(path, 0, ALUA_METADATA_PATH_LEN);
1260         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1261
1262         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1263                         se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1264
1265         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1266                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1267                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1268
1269         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1270                         "alua_tg_pt_status=0x%02x\n",
1271                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1272                         lun->lun_tg_pt_secondary_stat);
1273
1274         snprintf(path, ALUA_METADATA_PATH_LEN, "%s/alua/%s/%s/lun_%llu",
1275                         db_root, se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1276                         lun->unpacked_lun);
1277
1278         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1279         kfree(md_buf);
1280
1281 out_unlock:
1282         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1283         return rc;
1284 }
1285
1286 static int core_alua_set_tg_pt_secondary_state(
1287         struct se_lun *lun,
1288         int explicit,
1289         int offline)
1290 {
1291         struct t10_alua_tg_pt_gp *tg_pt_gp;
1292         int trans_delay_msecs;
1293
1294         spin_lock(&lun->lun_tg_pt_gp_lock);
1295         tg_pt_gp = lun->lun_tg_pt_gp;
1296         if (!tg_pt_gp) {
1297                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1298                 pr_err("Unable to complete secondary state"
1299                                 " transition\n");
1300                 return -EINVAL;
1301         }
1302         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1303         /*
1304          * Set the secondary ALUA target port access state to OFFLINE
1305          * or release the previously secondary state for struct se_lun
1306          */
1307         if (offline)
1308                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1309         else
1310                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1311
1312         lun->lun_tg_pt_secondary_stat = (explicit) ?
1313                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1314                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1315
1316         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1317                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1318                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1319                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1320
1321         spin_unlock(&lun->lun_tg_pt_gp_lock);
1322         /*
1323          * Do the optional transition delay after we set the secondary
1324          * ALUA access state.
1325          */
1326         if (trans_delay_msecs != 0)
1327                 msleep_interruptible(trans_delay_msecs);
1328         /*
1329          * See if we need to update the ALUA fabric port metadata for
1330          * secondary state and status
1331          */
1332         if (lun->lun_tg_pt_secondary_write_md)
1333                 core_alua_update_tpg_secondary_metadata(lun);
1334
1335         return 0;
1336 }
1337
1338 struct t10_alua_lba_map *
1339 core_alua_allocate_lba_map(struct list_head *list,
1340                            u64 first_lba, u64 last_lba)
1341 {
1342         struct t10_alua_lba_map *lba_map;
1343
1344         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1345         if (!lba_map) {
1346                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1347                 return ERR_PTR(-ENOMEM);
1348         }
1349         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1350         lba_map->lba_map_first_lba = first_lba;
1351         lba_map->lba_map_last_lba = last_lba;
1352
1353         list_add_tail(&lba_map->lba_map_list, list);
1354         return lba_map;
1355 }
1356
1357 int
1358 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1359                                int pg_id, int state)
1360 {
1361         struct t10_alua_lba_map_member *lba_map_mem;
1362
1363         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1364                             lba_map_mem_list) {
1365                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1366                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1367                         return -EINVAL;
1368                 }
1369         }
1370
1371         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1372         if (!lba_map_mem) {
1373                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1374                 return -ENOMEM;
1375         }
1376         lba_map_mem->lba_map_mem_alua_state = state;
1377         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1378
1379         list_add_tail(&lba_map_mem->lba_map_mem_list,
1380                       &lba_map->lba_map_mem_list);
1381         return 0;
1382 }
1383
1384 void
1385 core_alua_free_lba_map(struct list_head *lba_list)
1386 {
1387         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1388         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1389
1390         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1391                                  lba_map_list) {
1392                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1393                                          &lba_map->lba_map_mem_list,
1394                                          lba_map_mem_list) {
1395                         list_del(&lba_map_mem->lba_map_mem_list);
1396                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1397                                         lba_map_mem);
1398                 }
1399                 list_del(&lba_map->lba_map_list);
1400                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1401         }
1402 }
1403
1404 void
1405 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1406                       int segment_size, int segment_mult)
1407 {
1408         struct list_head old_lba_map_list;
1409         struct t10_alua_tg_pt_gp *tg_pt_gp;
1410         int activate = 0, supported;
1411
1412         INIT_LIST_HEAD(&old_lba_map_list);
1413         spin_lock(&dev->t10_alua.lba_map_lock);
1414         dev->t10_alua.lba_map_segment_size = segment_size;
1415         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1416         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1417         if (lba_map_list) {
1418                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1419                 activate = 1;
1420         }
1421         spin_unlock(&dev->t10_alua.lba_map_lock);
1422         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1423         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1424                             tg_pt_gp_list) {
1425
1426                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1427                         continue;
1428                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1429                 if (activate)
1430                         supported |= ALUA_LBD_SUP;
1431                 else
1432                         supported &= ~ALUA_LBD_SUP;
1433                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1434         }
1435         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1436         core_alua_free_lba_map(&old_lba_map_list);
1437 }
1438
1439 struct t10_alua_lu_gp *
1440 core_alua_allocate_lu_gp(const char *name, int def_group)
1441 {
1442         struct t10_alua_lu_gp *lu_gp;
1443
1444         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1445         if (!lu_gp) {
1446                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1447                 return ERR_PTR(-ENOMEM);
1448         }
1449         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1450         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1451         spin_lock_init(&lu_gp->lu_gp_lock);
1452         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1453
1454         if (def_group) {
1455                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1456                 lu_gp->lu_gp_valid_id = 1;
1457                 alua_lu_gps_count++;
1458         }
1459
1460         return lu_gp;
1461 }
1462
1463 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1464 {
1465         struct t10_alua_lu_gp *lu_gp_tmp;
1466         u16 lu_gp_id_tmp;
1467         /*
1468          * The lu_gp->lu_gp_id may only be set once..
1469          */
1470         if (lu_gp->lu_gp_valid_id) {
1471                 pr_warn("ALUA LU Group already has a valid ID,"
1472                         " ignoring request\n");
1473                 return -EINVAL;
1474         }
1475
1476         spin_lock(&lu_gps_lock);
1477         if (alua_lu_gps_count == 0x0000ffff) {
1478                 pr_err("Maximum ALUA alua_lu_gps_count:"
1479                                 " 0x0000ffff reached\n");
1480                 spin_unlock(&lu_gps_lock);
1481                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1482                 return -ENOSPC;
1483         }
1484 again:
1485         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1486                                 alua_lu_gps_counter++;
1487
1488         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1489                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1490                         if (!lu_gp_id)
1491                                 goto again;
1492
1493                         pr_warn("ALUA Logical Unit Group ID: %hu"
1494                                 " already exists, ignoring request\n",
1495                                 lu_gp_id);
1496                         spin_unlock(&lu_gps_lock);
1497                         return -EINVAL;
1498                 }
1499         }
1500
1501         lu_gp->lu_gp_id = lu_gp_id_tmp;
1502         lu_gp->lu_gp_valid_id = 1;
1503         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1504         alua_lu_gps_count++;
1505         spin_unlock(&lu_gps_lock);
1506
1507         return 0;
1508 }
1509
1510 static struct t10_alua_lu_gp_member *
1511 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1512 {
1513         struct t10_alua_lu_gp_member *lu_gp_mem;
1514
1515         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1516         if (!lu_gp_mem) {
1517                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1518                 return ERR_PTR(-ENOMEM);
1519         }
1520         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1521         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1522         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1523
1524         lu_gp_mem->lu_gp_mem_dev = dev;
1525         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1526
1527         return lu_gp_mem;
1528 }
1529
1530 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1531 {
1532         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1533         /*
1534          * Once we have reached this point, config_item_put() has
1535          * already been called from target_core_alua_drop_lu_gp().
1536          *
1537          * Here, we remove the *lu_gp from the global list so that
1538          * no associations can be made while we are releasing
1539          * struct t10_alua_lu_gp.
1540          */
1541         spin_lock(&lu_gps_lock);
1542         list_del(&lu_gp->lu_gp_node);
1543         alua_lu_gps_count--;
1544         spin_unlock(&lu_gps_lock);
1545         /*
1546          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1547          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1548          * released with core_alua_put_lu_gp_from_name()
1549          */
1550         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1551                 cpu_relax();
1552         /*
1553          * Release reference to struct t10_alua_lu_gp * from all associated
1554          * struct se_device.
1555          */
1556         spin_lock(&lu_gp->lu_gp_lock);
1557         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1558                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
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                 /*
1566                  *
1567                  * lu_gp_mem is associated with a single
1568                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1569                  * struct se_device is released via core_alua_free_lu_gp_mem().
1570                  *
1571                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1572                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1573                  */
1574                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1575                 if (lu_gp != default_lu_gp)
1576                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1577                                         default_lu_gp);
1578                 else
1579                         lu_gp_mem->lu_gp = NULL;
1580                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1581
1582                 spin_lock(&lu_gp->lu_gp_lock);
1583         }
1584         spin_unlock(&lu_gp->lu_gp_lock);
1585
1586         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1587 }
1588
1589 void core_alua_free_lu_gp_mem(struct se_device *dev)
1590 {
1591         struct t10_alua_lu_gp *lu_gp;
1592         struct t10_alua_lu_gp_member *lu_gp_mem;
1593
1594         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1595         if (!lu_gp_mem)
1596                 return;
1597
1598         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1599                 cpu_relax();
1600
1601         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1602         lu_gp = lu_gp_mem->lu_gp;
1603         if (lu_gp) {
1604                 spin_lock(&lu_gp->lu_gp_lock);
1605                 if (lu_gp_mem->lu_gp_assoc) {
1606                         list_del(&lu_gp_mem->lu_gp_mem_list);
1607                         lu_gp->lu_gp_members--;
1608                         lu_gp_mem->lu_gp_assoc = 0;
1609                 }
1610                 spin_unlock(&lu_gp->lu_gp_lock);
1611                 lu_gp_mem->lu_gp = NULL;
1612         }
1613         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1614
1615         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1616 }
1617
1618 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1619 {
1620         struct t10_alua_lu_gp *lu_gp;
1621         struct config_item *ci;
1622
1623         spin_lock(&lu_gps_lock);
1624         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1625                 if (!lu_gp->lu_gp_valid_id)
1626                         continue;
1627                 ci = &lu_gp->lu_gp_group.cg_item;
1628                 if (!strcmp(config_item_name(ci), name)) {
1629                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1630                         spin_unlock(&lu_gps_lock);
1631                         return lu_gp;
1632                 }
1633         }
1634         spin_unlock(&lu_gps_lock);
1635
1636         return NULL;
1637 }
1638
1639 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1640 {
1641         spin_lock(&lu_gps_lock);
1642         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1643         spin_unlock(&lu_gps_lock);
1644 }
1645
1646 /*
1647  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1648  */
1649 void __core_alua_attach_lu_gp_mem(
1650         struct t10_alua_lu_gp_member *lu_gp_mem,
1651         struct t10_alua_lu_gp *lu_gp)
1652 {
1653         spin_lock(&lu_gp->lu_gp_lock);
1654         lu_gp_mem->lu_gp = lu_gp;
1655         lu_gp_mem->lu_gp_assoc = 1;
1656         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1657         lu_gp->lu_gp_members++;
1658         spin_unlock(&lu_gp->lu_gp_lock);
1659 }
1660
1661 /*
1662  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1663  */
1664 void __core_alua_drop_lu_gp_mem(
1665         struct t10_alua_lu_gp_member *lu_gp_mem,
1666         struct t10_alua_lu_gp *lu_gp)
1667 {
1668         spin_lock(&lu_gp->lu_gp_lock);
1669         list_del(&lu_gp_mem->lu_gp_mem_list);
1670         lu_gp_mem->lu_gp = NULL;
1671         lu_gp_mem->lu_gp_assoc = 0;
1672         lu_gp->lu_gp_members--;
1673         spin_unlock(&lu_gp->lu_gp_lock);
1674 }
1675
1676 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1677                 const char *name, int def_group)
1678 {
1679         struct t10_alua_tg_pt_gp *tg_pt_gp;
1680
1681         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1682         if (!tg_pt_gp) {
1683                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1684                 return NULL;
1685         }
1686         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1687         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1688         mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1689         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1690         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1691         INIT_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1692                   core_alua_do_transition_tg_pt_work);
1693         tg_pt_gp->tg_pt_gp_dev = dev;
1694         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1695                 ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1696         /*
1697          * Enable both explicit and implicit ALUA support by default
1698          */
1699         tg_pt_gp->tg_pt_gp_alua_access_type =
1700                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1701         /*
1702          * Set the default Active/NonOptimized Delay in milliseconds
1703          */
1704         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1705         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1706         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1707
1708         /*
1709          * Enable all supported states
1710          */
1711         tg_pt_gp->tg_pt_gp_alua_supported_states =
1712             ALUA_T_SUP | ALUA_O_SUP |
1713             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1714
1715         if (def_group) {
1716                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1717                 tg_pt_gp->tg_pt_gp_id =
1718                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1719                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1720                 dev->t10_alua.alua_tg_pt_gps_count++;
1721                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1722                               &dev->t10_alua.tg_pt_gps_list);
1723                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1724         }
1725
1726         return tg_pt_gp;
1727 }
1728
1729 int core_alua_set_tg_pt_gp_id(
1730         struct t10_alua_tg_pt_gp *tg_pt_gp,
1731         u16 tg_pt_gp_id)
1732 {
1733         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1734         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1735         u16 tg_pt_gp_id_tmp;
1736
1737         /*
1738          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1739          */
1740         if (tg_pt_gp->tg_pt_gp_valid_id) {
1741                 pr_warn("ALUA TG PT Group already has a valid ID,"
1742                         " ignoring request\n");
1743                 return -EINVAL;
1744         }
1745
1746         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1747         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1748                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1749                         " 0x0000ffff reached\n");
1750                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1751                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1752                 return -ENOSPC;
1753         }
1754 again:
1755         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1756                         dev->t10_alua.alua_tg_pt_gps_counter++;
1757
1758         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1759                         tg_pt_gp_list) {
1760                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1761                         if (!tg_pt_gp_id)
1762                                 goto again;
1763
1764                         pr_err("ALUA Target Port Group ID: %hu already"
1765                                 " exists, ignoring request\n", tg_pt_gp_id);
1766                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1767                         return -EINVAL;
1768                 }
1769         }
1770
1771         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1772         tg_pt_gp->tg_pt_gp_valid_id = 1;
1773         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1774                         &dev->t10_alua.tg_pt_gps_list);
1775         dev->t10_alua.alua_tg_pt_gps_count++;
1776         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1777
1778         return 0;
1779 }
1780
1781 void core_alua_free_tg_pt_gp(
1782         struct t10_alua_tg_pt_gp *tg_pt_gp)
1783 {
1784         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1785         struct se_lun *lun, *next;
1786
1787         /*
1788          * Once we have reached this point, config_item_put() has already
1789          * been called from target_core_alua_drop_tg_pt_gp().
1790          *
1791          * Here we remove *tg_pt_gp from the global list so that
1792          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1793          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1794          */
1795         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1796         list_del(&tg_pt_gp->tg_pt_gp_list);
1797         dev->t10_alua.alua_tg_pt_gps_counter--;
1798         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1799
1800         flush_work(&tg_pt_gp->tg_pt_gp_transition_work);
1801
1802         /*
1803          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1804          * core_alua_get_tg_pt_gp_by_name() in
1805          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1806          * to be released with core_alua_put_tg_pt_gp_from_name().
1807          */
1808         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1809                 cpu_relax();
1810
1811         /*
1812          * Release reference to struct t10_alua_tg_pt_gp from all associated
1813          * struct se_port.
1814          */
1815         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1816         list_for_each_entry_safe(lun, next,
1817                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1818                 list_del_init(&lun->lun_tg_pt_gp_link);
1819                 tg_pt_gp->tg_pt_gp_members--;
1820
1821                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1822                 /*
1823                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1824                  * assume we want to re-associate a given tg_pt_gp_mem with
1825                  * default_tg_pt_gp.
1826                  */
1827                 spin_lock(&lun->lun_tg_pt_gp_lock);
1828                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1829                         __target_attach_tg_pt_gp(lun,
1830                                         dev->t10_alua.default_tg_pt_gp);
1831                 } else
1832                         lun->lun_tg_pt_gp = NULL;
1833                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1834
1835                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1836         }
1837         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1838
1839         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1840 }
1841
1842 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1843                 struct se_device *dev, const char *name)
1844 {
1845         struct t10_alua_tg_pt_gp *tg_pt_gp;
1846         struct config_item *ci;
1847
1848         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1849         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1850                         tg_pt_gp_list) {
1851                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1852                         continue;
1853                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1854                 if (!strcmp(config_item_name(ci), name)) {
1855                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1856                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1857                         return tg_pt_gp;
1858                 }
1859         }
1860         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1861
1862         return NULL;
1863 }
1864
1865 static void core_alua_put_tg_pt_gp_from_name(
1866         struct t10_alua_tg_pt_gp *tg_pt_gp)
1867 {
1868         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1869
1870         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1871         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1872         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1873 }
1874
1875 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1876                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1877 {
1878         struct se_dev_entry *se_deve;
1879
1880         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1881
1882         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1883         lun->lun_tg_pt_gp = tg_pt_gp;
1884         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1885         tg_pt_gp->tg_pt_gp_members++;
1886         spin_lock(&lun->lun_deve_lock);
1887         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1888                 core_scsi3_ua_allocate(se_deve, 0x3f,
1889                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1890         spin_unlock(&lun->lun_deve_lock);
1891         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1892 }
1893
1894 void target_attach_tg_pt_gp(struct se_lun *lun,
1895                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1896 {
1897         spin_lock(&lun->lun_tg_pt_gp_lock);
1898         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1899         spin_unlock(&lun->lun_tg_pt_gp_lock);
1900 }
1901
1902 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1903                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1904 {
1905         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1906
1907         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1908         list_del_init(&lun->lun_tg_pt_gp_link);
1909         tg_pt_gp->tg_pt_gp_members--;
1910         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1911
1912         lun->lun_tg_pt_gp = NULL;
1913 }
1914
1915 void target_detach_tg_pt_gp(struct se_lun *lun)
1916 {
1917         struct t10_alua_tg_pt_gp *tg_pt_gp;
1918
1919         spin_lock(&lun->lun_tg_pt_gp_lock);
1920         tg_pt_gp = lun->lun_tg_pt_gp;
1921         if (tg_pt_gp)
1922                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1923         spin_unlock(&lun->lun_tg_pt_gp_lock);
1924 }
1925
1926 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1927 {
1928         struct config_item *tg_pt_ci;
1929         struct t10_alua_tg_pt_gp *tg_pt_gp;
1930         ssize_t len = 0;
1931
1932         spin_lock(&lun->lun_tg_pt_gp_lock);
1933         tg_pt_gp = lun->lun_tg_pt_gp;
1934         if (tg_pt_gp) {
1935                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1936                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1937                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1938                         "Primary Access Status: %s\nTG Port Secondary Access"
1939                         " State: %s\nTG Port Secondary Access Status: %s\n",
1940                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1941                         core_alua_dump_state(atomic_read(
1942                                         &tg_pt_gp->tg_pt_gp_alua_access_state)),
1943                         core_alua_dump_status(
1944                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1945                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1946                         "Offline" : "None",
1947                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1948         }
1949         spin_unlock(&lun->lun_tg_pt_gp_lock);
1950
1951         return len;
1952 }
1953
1954 ssize_t core_alua_store_tg_pt_gp_info(
1955         struct se_lun *lun,
1956         const char *page,
1957         size_t count)
1958 {
1959         struct se_portal_group *tpg = lun->lun_tpg;
1960         /*
1961          * rcu_dereference_raw protected by se_lun->lun_group symlink
1962          * reference to se_device->dev_group.
1963          */
1964         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1965         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1966         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1967         int move = 0;
1968
1969         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1970             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1971                 return -ENODEV;
1972
1973         if (count > TG_PT_GROUP_NAME_BUF) {
1974                 pr_err("ALUA Target Port Group alias too large!\n");
1975                 return -EINVAL;
1976         }
1977         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1978         memcpy(buf, page, count);
1979         /*
1980          * Any ALUA target port group alias besides "NULL" means we will be
1981          * making a new group association.
1982          */
1983         if (strcmp(strstrip(buf), "NULL")) {
1984                 /*
1985                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1986                  * struct t10_alua_tg_pt_gp.  This reference is released with
1987                  * core_alua_put_tg_pt_gp_from_name() below.
1988                  */
1989                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1990                                         strstrip(buf));
1991                 if (!tg_pt_gp_new)
1992                         return -ENODEV;
1993         }
1994
1995         spin_lock(&lun->lun_tg_pt_gp_lock);
1996         tg_pt_gp = lun->lun_tg_pt_gp;
1997         if (tg_pt_gp) {
1998                 /*
1999                  * Clearing an existing tg_pt_gp association, and replacing
2000                  * with the default_tg_pt_gp.
2001                  */
2002                 if (!tg_pt_gp_new) {
2003                         pr_debug("Target_Core_ConfigFS: Moving"
2004                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
2005                                 " alua/%s, ID: %hu back to"
2006                                 " default_tg_pt_gp\n",
2007                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2008                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
2009                                 config_item_name(&lun->lun_group.cg_item),
2010                                 config_item_name(
2011                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
2012                                 tg_pt_gp->tg_pt_gp_id);
2013
2014                         __target_detach_tg_pt_gp(lun, tg_pt_gp);
2015                         __target_attach_tg_pt_gp(lun,
2016                                         dev->t10_alua.default_tg_pt_gp);
2017                         spin_unlock(&lun->lun_tg_pt_gp_lock);
2018
2019                         return count;
2020                 }
2021                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
2022                 move = 1;
2023         }
2024
2025         __target_attach_tg_pt_gp(lun, tg_pt_gp_new);
2026         spin_unlock(&lun->lun_tg_pt_gp_lock);
2027         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2028                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
2029                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2030                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
2031                 config_item_name(&lun->lun_group.cg_item),
2032                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2033                 tg_pt_gp_new->tg_pt_gp_id);
2034
2035         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2036         return count;
2037 }
2038
2039 ssize_t core_alua_show_access_type(
2040         struct t10_alua_tg_pt_gp *tg_pt_gp,
2041         char *page)
2042 {
2043         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2044             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2045                 return sprintf(page, "Implicit and Explicit\n");
2046         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2047                 return sprintf(page, "Implicit\n");
2048         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2049                 return sprintf(page, "Explicit\n");
2050         else
2051                 return sprintf(page, "None\n");
2052 }
2053
2054 ssize_t core_alua_store_access_type(
2055         struct t10_alua_tg_pt_gp *tg_pt_gp,
2056         const char *page,
2057         size_t count)
2058 {
2059         unsigned long tmp;
2060         int ret;
2061
2062         ret = kstrtoul(page, 0, &tmp);
2063         if (ret < 0) {
2064                 pr_err("Unable to extract alua_access_type\n");
2065                 return ret;
2066         }
2067         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2068                 pr_err("Illegal value for alua_access_type:"
2069                                 " %lu\n", tmp);
2070                 return -EINVAL;
2071         }
2072         if (tmp == 3)
2073                 tg_pt_gp->tg_pt_gp_alua_access_type =
2074                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2075         else if (tmp == 2)
2076                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2077         else if (tmp == 1)
2078                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2079         else
2080                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2081
2082         return count;
2083 }
2084
2085 ssize_t core_alua_show_nonop_delay_msecs(
2086         struct t10_alua_tg_pt_gp *tg_pt_gp,
2087         char *page)
2088 {
2089         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2090 }
2091
2092 ssize_t core_alua_store_nonop_delay_msecs(
2093         struct t10_alua_tg_pt_gp *tg_pt_gp,
2094         const char *page,
2095         size_t count)
2096 {
2097         unsigned long tmp;
2098         int ret;
2099
2100         ret = kstrtoul(page, 0, &tmp);
2101         if (ret < 0) {
2102                 pr_err("Unable to extract nonop_delay_msecs\n");
2103                 return ret;
2104         }
2105         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2106                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2107                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2108                         ALUA_MAX_NONOP_DELAY_MSECS);
2109                 return -EINVAL;
2110         }
2111         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2112
2113         return count;
2114 }
2115
2116 ssize_t core_alua_show_trans_delay_msecs(
2117         struct t10_alua_tg_pt_gp *tg_pt_gp,
2118         char *page)
2119 {
2120         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2121 }
2122
2123 ssize_t core_alua_store_trans_delay_msecs(
2124         struct t10_alua_tg_pt_gp *tg_pt_gp,
2125         const char *page,
2126         size_t count)
2127 {
2128         unsigned long tmp;
2129         int ret;
2130
2131         ret = kstrtoul(page, 0, &tmp);
2132         if (ret < 0) {
2133                 pr_err("Unable to extract trans_delay_msecs\n");
2134                 return ret;
2135         }
2136         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2137                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2138                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2139                         ALUA_MAX_TRANS_DELAY_MSECS);
2140                 return -EINVAL;
2141         }
2142         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2143
2144         return count;
2145 }
2146
2147 ssize_t core_alua_show_implicit_trans_secs(
2148         struct t10_alua_tg_pt_gp *tg_pt_gp,
2149         char *page)
2150 {
2151         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2152 }
2153
2154 ssize_t core_alua_store_implicit_trans_secs(
2155         struct t10_alua_tg_pt_gp *tg_pt_gp,
2156         const char *page,
2157         size_t count)
2158 {
2159         unsigned long tmp;
2160         int ret;
2161
2162         ret = kstrtoul(page, 0, &tmp);
2163         if (ret < 0) {
2164                 pr_err("Unable to extract implicit_trans_secs\n");
2165                 return ret;
2166         }
2167         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2168                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2169                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2170                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2171                 return  -EINVAL;
2172         }
2173         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2174
2175         return count;
2176 }
2177
2178 ssize_t core_alua_show_preferred_bit(
2179         struct t10_alua_tg_pt_gp *tg_pt_gp,
2180         char *page)
2181 {
2182         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2183 }
2184
2185 ssize_t core_alua_store_preferred_bit(
2186         struct t10_alua_tg_pt_gp *tg_pt_gp,
2187         const char *page,
2188         size_t count)
2189 {
2190         unsigned long tmp;
2191         int ret;
2192
2193         ret = kstrtoul(page, 0, &tmp);
2194         if (ret < 0) {
2195                 pr_err("Unable to extract preferred ALUA value\n");
2196                 return ret;
2197         }
2198         if ((tmp != 0) && (tmp != 1)) {
2199                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2200                 return -EINVAL;
2201         }
2202         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2203
2204         return count;
2205 }
2206
2207 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2208 {
2209         return sprintf(page, "%d\n",
2210                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2211 }
2212
2213 ssize_t core_alua_store_offline_bit(
2214         struct se_lun *lun,
2215         const char *page,
2216         size_t count)
2217 {
2218         /*
2219          * rcu_dereference_raw protected by se_lun->lun_group symlink
2220          * reference to se_device->dev_group.
2221          */
2222         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2223         unsigned long tmp;
2224         int ret;
2225
2226         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2227             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2228                 return -ENODEV;
2229
2230         ret = kstrtoul(page, 0, &tmp);
2231         if (ret < 0) {
2232                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2233                 return ret;
2234         }
2235         if ((tmp != 0) && (tmp != 1)) {
2236                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2237                                 tmp);
2238                 return -EINVAL;
2239         }
2240
2241         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2242         if (ret < 0)
2243                 return -EINVAL;
2244
2245         return count;
2246 }
2247
2248 ssize_t core_alua_show_secondary_status(
2249         struct se_lun *lun,
2250         char *page)
2251 {
2252         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2253 }
2254
2255 ssize_t core_alua_store_secondary_status(
2256         struct se_lun *lun,
2257         const char *page,
2258         size_t count)
2259 {
2260         unsigned long tmp;
2261         int ret;
2262
2263         ret = kstrtoul(page, 0, &tmp);
2264         if (ret < 0) {
2265                 pr_err("Unable to extract alua_tg_pt_status\n");
2266                 return ret;
2267         }
2268         if ((tmp != ALUA_STATUS_NONE) &&
2269             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2270             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2271                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2272                                 tmp);
2273                 return -EINVAL;
2274         }
2275         lun->lun_tg_pt_secondary_stat = (int)tmp;
2276
2277         return count;
2278 }
2279
2280 ssize_t core_alua_show_secondary_write_metadata(
2281         struct se_lun *lun,
2282         char *page)
2283 {
2284         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2285 }
2286
2287 ssize_t core_alua_store_secondary_write_metadata(
2288         struct se_lun *lun,
2289         const char *page,
2290         size_t count)
2291 {
2292         unsigned long tmp;
2293         int ret;
2294
2295         ret = kstrtoul(page, 0, &tmp);
2296         if (ret < 0) {
2297                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2298                 return ret;
2299         }
2300         if ((tmp != 0) && (tmp != 1)) {
2301                 pr_err("Illegal value for alua_tg_pt_write_md:"
2302                                 " %lu\n", tmp);
2303                 return -EINVAL;
2304         }
2305         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2306
2307         return count;
2308 }
2309
2310 int core_setup_alua(struct se_device *dev)
2311 {
2312         if (!(dev->transport->transport_flags &
2313              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2314             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2315                 struct t10_alua_lu_gp_member *lu_gp_mem;
2316
2317                 /*
2318                  * Associate this struct se_device with the default ALUA
2319                  * LUN Group.
2320                  */
2321                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2322                 if (IS_ERR(lu_gp_mem))
2323                         return PTR_ERR(lu_gp_mem);
2324
2325                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2326                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2327                                 default_lu_gp);
2328                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2329
2330                 pr_debug("%s: Adding to default ALUA LU Group:"
2331                         " core/alua/lu_gps/default_lu_gp\n",
2332                         dev->transport->name);
2333         }
2334
2335         return 0;
2336 }