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/export.h>
  30 #include <linux/file.h>
  31 #include <scsi/scsi_proto.h>
  32 #include <asm/unaligned.h>
  33
  34 #include <target/target_core_base.h>
  35 #include <target/target_core_backend.h>
  36 #include <target/target_core_fabric.h>
  37
  38 #include "target_core_internal.h"
  39 #include "target_core_alua.h"
  40 #include "target_core_ua.h"
  41
  42 static sense_reason_t core_alua_check_transition(int state, int valid,
  43                                                  int *primary);
  44 static int core_alua_set_tg_pt_secondary_state(
  45                 struct se_lun *lun, int explicit, int offline);
  46
  47 static char *core_alua_dump_state(int state);
  48
  49 static void __target_attach_tg_pt_gp(struct se_lun *lun,
  50                 struct t10_alua_tg_pt_gp *tg_pt_gp);
  51
  52 static u16 alua_lu_gps_counter;
  53 static u32 alua_lu_gps_count;
  54
  55 static DEFINE_SPINLOCK(lu_gps_lock);
  56 static LIST_HEAD(lu_gps_list);
  57
  58 struct t10_alua_lu_gp *default_lu_gp;
  59
  60 /*
  61  * REPORT REFERRALS
  62  *
  63  * See sbc3r35 section 5.23
  64  */
  65 sense_reason_t
  66 target_emulate_report_referrals(struct se_cmd *cmd)
  67 {
  68         struct se_device *dev = cmd->se_dev;
  69         struct t10_alua_lba_map *map;
  70         struct t10_alua_lba_map_member *map_mem;
  71         unsigned char *buf;
  72         u32 rd_len = 0, off;
  73
  74         if (cmd->data_length < 4) {
  75                 pr_warn("REPORT REFERRALS allocation length %u too"
  76                         " small\n", cmd->data_length);
  77                 return TCM_INVALID_CDB_FIELD;
  78         }
  79
  80         buf = transport_kmap_data_sg(cmd);
  81         if (!buf)
  82                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
  83
  84         off = 4;
  85         spin_lock(&dev->t10_alua.lba_map_lock);
  86         if (list_empty(&dev->t10_alua.lba_map_list)) {
  87                 spin_unlock(&dev->t10_alua.lba_map_lock);
  88                 transport_kunmap_data_sg(cmd);
  89
  90                 return TCM_UNSUPPORTED_SCSI_OPCODE;
  91         }
  92
  93         list_for_each_entry(map, &dev->t10_alua.lba_map_list,
  94                             lba_map_list) {
  95                 int desc_num = off + 3;
  96                 int pg_num;
  97
  98                 off += 4;
  99                 if (cmd->data_length > off)
 100                         put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
 101                 off += 8;
 102                 if (cmd->data_length > off)
 103                         put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
 104                 off += 8;
 105                 rd_len += 20;
 106                 pg_num = 0;
 107                 list_for_each_entry(map_mem, &map->lba_map_mem_list,
 108                                     lba_map_mem_list) {
 109                         int alua_state = map_mem->lba_map_mem_alua_state;
 110                         int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
 111
 112                         if (cmd->data_length > off)
 113                                 buf[off] = alua_state & 0x0f;
 114                         off += 2;
 115                         if (cmd->data_length > off)
 116                                 buf[off] = (alua_pg_id >> 8) & 0xff;
 117                         off++;
 118                         if (cmd->data_length > off)
 119                                 buf[off] = (alua_pg_id & 0xff);
 120                         off++;
 121                         rd_len += 4;
 122                         pg_num++;
 123                 }
 124                 if (cmd->data_length > desc_num)
 125                         buf[desc_num] = pg_num;
 126         }
 127         spin_unlock(&dev->t10_alua.lba_map_lock);
 128
 129         /*
 130          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 131          */
 132         put_unaligned_be16(rd_len, &buf[2]);
 133
 134         transport_kunmap_data_sg(cmd);
 135
 136         target_complete_cmd(cmd, GOOD);
 137         return 0;
 138 }
 139
 140 /*
 141  * REPORT_TARGET_PORT_GROUPS
 142  *
 143  * See spc4r17 section 6.27
 144  */
 145 sense_reason_t
 146 target_emulate_report_target_port_groups(struct se_cmd *cmd)
 147 {
 148         struct se_device *dev = cmd->se_dev;
 149         struct t10_alua_tg_pt_gp *tg_pt_gp;
 150         struct se_lun *lun;
 151         unsigned char *buf;
 152         u32 rd_len = 0, off;
 153         int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
 154
 155         /*
 156          * Skip over RESERVED area to first Target port group descriptor
 157          * depending on the PARAMETER DATA FORMAT type..
 158          */
 159         if (ext_hdr != 0)
 160                 off = 8;
 161         else
 162                 off = 4;
 163
 164         if (cmd->data_length < off) {
 165                 pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
 166                         " small for %s header\n", cmd->data_length,
 167                         (ext_hdr) ? "extended" : "normal");
 168                 return TCM_INVALID_CDB_FIELD;
 169         }
 170         buf = transport_kmap_data_sg(cmd);
 171         if (!buf)
 172                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 173
 174         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 175         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
 176                         tg_pt_gp_list) {
 177                 /*
 178                  * Check if the Target port group and Target port descriptor list
 179                  * based on tg_pt_gp_members count will fit into the response payload.
 180                  * Otherwise, bump rd_len to let the initiator know we have exceeded
 181                  * the allocation length and the response is truncated.
 182                  */
 183                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
 184                      cmd->data_length) {
 185                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
 186                         continue;
 187                 }
 188                 /*
 189                  * PREF: Preferred target port bit, determine if this
 190                  * bit should be set for port group.
 191                  */
 192                 if (tg_pt_gp->tg_pt_gp_pref)
 193                         buf[off] = 0x80;
 194                 /*
 195                  * Set the ASYMMETRIC ACCESS State
 196                  */
 197                 buf[off++] |= (atomic_read(
 198                         &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
 199                 /*
 200                  * Set supported ASYMMETRIC ACCESS State bits
 201                  */
 202                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
 203                 /*
 204                  * TARGET PORT GROUP
 205                  */
 206                 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
 207                 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
 208
 209                 off++; /* Skip over Reserved */
 210                 /*
 211                  * STATUS CODE
 212                  */
 213                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 214                 /*
 215                  * Vendor Specific field
 216                  */
 217                 buf[off++] = 0x00;
 218                 /*
 219                  * TARGET PORT COUNT
 220                  */
 221                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 222                 rd_len += 8;
 223
 224                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 225                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 226                                 lun_tg_pt_gp_link) {
 227                         /*
 228                          * Start Target Port descriptor format
 229                          *
 230                          * See spc4r17 section 6.2.7 Table 247
 231                          */
 232                         off += 2; /* Skip over Obsolete */
 233                         /*
 234                          * Set RELATIVE TARGET PORT IDENTIFIER
 235                          */
 236                         buf[off++] = ((lun->lun_rtpi >> 8) & 0xff);
 237                         buf[off++] = (lun->lun_rtpi & 0xff);
 238                         rd_len += 4;
 239                 }
 240                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 241         }
 242         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 243         /*
 244          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 245          */
 246         put_unaligned_be32(rd_len, &buf[0]);
 247
 248         /*
 249          * Fill in the Extended header parameter data format if requested
 250          */
 251         if (ext_hdr != 0) {
 252                 buf[4] = 0x10;
 253                 /*
 254                  * Set the implicit transition time (in seconds) for the application
 255                  * client to use as a base for it's transition timeout value.
 256                  *
 257                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
 258                  * this CDB was received upon to determine this value individually
 259                  * for ALUA target port group.
 260                  */
 261                 spin_lock(&cmd->se_lun->lun_tg_pt_gp_lock);
 262                 tg_pt_gp = cmd->se_lun->lun_tg_pt_gp;
 263                 if (tg_pt_gp)
 264                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
 265                 spin_unlock(&cmd->se_lun->lun_tg_pt_gp_lock);
 266         }
 267         transport_kunmap_data_sg(cmd);
 268
 269         target_complete_cmd(cmd, GOOD);
 270         return 0;
 271 }
 272
 273 /*
 274  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
 275  *
 276  * See spc4r17 section 6.35
 277  */
 278 sense_reason_t
 279 target_emulate_set_target_port_groups(struct se_cmd *cmd)
 280 {
 281         struct se_device *dev = cmd->se_dev;
 282         struct se_lun *l_lun = cmd->se_lun;
 283         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 284         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 285         unsigned char *buf;
 286         unsigned char *ptr;
 287         sense_reason_t rc = TCM_NO_SENSE;
 288         u32 len = 4; /* Skip over RESERVED area in header */
 289         int alua_access_state, primary = 0, valid_states;
 290         u16 tg_pt_id, rtpi;
 291
 292         if (cmd->data_length < 4) {
 293                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
 294                         " small\n", cmd->data_length);
 295                 return TCM_INVALID_PARAMETER_LIST;
 296         }
 297
 298         buf = transport_kmap_data_sg(cmd);
 299         if (!buf)
 300                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 301
 302         /*
 303          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
 304          * for the local tg_pt_gp.
 305          */
 306         spin_lock(&l_lun->lun_tg_pt_gp_lock);
 307         l_tg_pt_gp = l_lun->lun_tg_pt_gp;
 308         if (!l_tg_pt_gp) {
 309                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 310                 pr_err("Unable to access l_lun->tg_pt_gp\n");
 311                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 312                 goto out;
 313         }
 314
 315         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
 316                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 317                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 318                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
 319                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 320                 goto out;
 321         }
 322         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
 323         spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 324
 325         ptr = &buf[4]; /* Skip over RESERVED area in header */
 326
 327         while (len < cmd->data_length) {
 328                 bool found = false;
 329                 alua_access_state = (ptr[0] & 0x0f);
 330                 /*
 331                  * Check the received ALUA access state, and determine if
 332                  * the state is a primary or secondary target port asymmetric
 333                  * access state.
 334                  */
 335                 rc = core_alua_check_transition(alua_access_state,
 336                                                 valid_states, &primary);
 337                 if (rc) {
 338                         /*
 339                          * If the SET TARGET PORT GROUPS attempts to establish
 340                          * an invalid combination of target port asymmetric
 341                          * access states or attempts to establish an
 342                          * unsupported target port asymmetric access state,
 343                          * then the command shall be terminated with CHECK
 344                          * CONDITION status, with the sense key set to ILLEGAL
 345                          * REQUEST, and the additional sense code set to INVALID
 346                          * FIELD IN PARAMETER LIST.
 347                          */
 348                         goto out;
 349                 }
 350
 351                 /*
 352                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 353                  * specifies a primary target port asymmetric access state,
 354                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 355                  * a primary target port group for which the primary target
 356                  * port asymmetric access state shall be changed. If the
 357                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 358                  * port asymmetric access state, then the TARGET PORT GROUP OR
 359                  * TARGET PORT field specifies the relative target port
 360                  * identifier (see 3.1.120) of the target port for which the
 361                  * secondary target port asymmetric access state shall be
 362                  * changed.
 363                  */
 364                 if (primary) {
 365                         tg_pt_id = get_unaligned_be16(ptr + 2);
 366                         /*
 367                          * Locate the matching target port group ID from
 368                          * the global tg_pt_gp list
 369                          */
 370                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 371                         list_for_each_entry(tg_pt_gp,
 372                                         &dev->t10_alua.tg_pt_gps_list,
 373                                         tg_pt_gp_list) {
 374                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 375                                         continue;
 376
 377                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 378                                         continue;
 379
 380                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 381
 382                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 383
 384                                 if (!core_alua_do_port_transition(tg_pt_gp,
 385                                                 dev, l_lun, nacl,
 386                                                 alua_access_state, 1))
 387                                         found = true;
 388
 389                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 390                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 391                                 break;
 392                         }
 393                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 394                 } else {
 395                         struct se_lun *lun;
 396
 397                         /*
 398                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
 399                          * the Target Port in question for the the incoming
 400                          * SET_TARGET_PORT_GROUPS op.
 401                          */
 402                         rtpi = get_unaligned_be16(ptr + 2);
 403                         /*
 404                          * Locate the matching relative target port identifier
 405                          * for the struct se_device storage object.
 406                          */
 407                         spin_lock(&dev->se_port_lock);
 408                         list_for_each_entry(lun, &dev->dev_sep_list,
 409                                                         lun_dev_link) {
 410                                 if (lun->lun_rtpi != rtpi)
 411                                         continue;
 412
 413                                 // XXX: racy unlock
 414                                 spin_unlock(&dev->se_port_lock);
 415
 416                                 if (!core_alua_set_tg_pt_secondary_state(
 417                                                 lun, 1, 1))
 418                                         found = true;
 419
 420                                 spin_lock(&dev->se_port_lock);
 421                                 break;
 422                         }
 423                         spin_unlock(&dev->se_port_lock);
 424                 }
 425
 426                 if (!found) {
 427                         rc = TCM_INVALID_PARAMETER_LIST;
 428                         goto out;
 429                 }
 430
 431                 ptr += 4;
 432                 len += 4;
 433         }
 434
 435 out:
 436         transport_kunmap_data_sg(cmd);
 437         if (!rc)
 438                 target_complete_cmd(cmd, GOOD);
 439         return rc;
 440 }
 441
 442 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
 443 {
 444         /*
 445          * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
 446          * The ALUA additional sense code qualifier (ASCQ) is determined
 447          * by the ALUA primary or secondary access state..
 448          */
 449         pr_debug("[%s]: ALUA TG Port not available, "
 450                 "SenseKey: NOT_READY, ASC/ASCQ: "
 451                 "0x04/0x%02x\n",
 452                 cmd->se_tfo->get_fabric_name(), alua_ascq);
 453
 454         cmd->scsi_asc = 0x04;
 455         cmd->scsi_ascq = alua_ascq;
 456 }
 457
 458 static inline void core_alua_state_nonoptimized(
 459         struct se_cmd *cmd,
 460         unsigned char *cdb,
 461         int nonop_delay_msecs)
 462 {
 463         /*
 464          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 465          * later to determine if processing of this cmd needs to be
 466          * temporarily delayed for the Active/NonOptimized primary access state.
 467          */
 468         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 469         cmd->alua_nonop_delay = nonop_delay_msecs;
 470 }
 471
 472 static inline int core_alua_state_lba_dependent(
 473         struct se_cmd *cmd,
 474         struct t10_alua_tg_pt_gp *tg_pt_gp)
 475 {
 476         struct se_device *dev = cmd->se_dev;
 477         u64 segment_size, segment_mult, sectors, lba;
 478
 479         /* Only need to check for cdb actually containing LBAs */
 480         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
 481                 return 0;
 482
 483         spin_lock(&dev->t10_alua.lba_map_lock);
 484         segment_size = dev->t10_alua.lba_map_segment_size;
 485         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
 486         sectors = cmd->data_length / dev->dev_attrib.block_size;
 487
 488         lba = cmd->t_task_lba;
 489         while (lba < cmd->t_task_lba + sectors) {
 490                 struct t10_alua_lba_map *cur_map = NULL, *map;
 491                 struct t10_alua_lba_map_member *map_mem;
 492
 493                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
 494                                     lba_map_list) {
 495                         u64 start_lba, last_lba;
 496                         u64 first_lba = map->lba_map_first_lba;
 497
 498                         if (segment_mult) {
 499                                 u64 tmp = lba;
 500                                 start_lba = do_div(tmp, segment_size * segment_mult);
 501
 502                                 last_lba = first_lba + segment_size - 1;
 503                                 if (start_lba >= first_lba &&
 504                                     start_lba <= last_lba) {
 505                                         lba += segment_size;
 506                                         cur_map = map;
 507                                         break;
 508                                 }
 509                         } else {
 510                                 last_lba = map->lba_map_last_lba;
 511                                 if (lba >= first_lba && lba <= last_lba) {
 512                                         lba = last_lba + 1;
 513                                         cur_map = map;
 514                                         break;
 515                                 }
 516                         }
 517                 }
 518                 if (!cur_map) {
 519                         spin_unlock(&dev->t10_alua.lba_map_lock);
 520                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 521                         return 1;
 522                 }
 523                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
 524                                     lba_map_mem_list) {
 525                         if (map_mem->lba_map_mem_alua_pg_id !=
 526                             tg_pt_gp->tg_pt_gp_id)
 527                                 continue;
 528                         switch(map_mem->lba_map_mem_alua_state) {
 529                         case ALUA_ACCESS_STATE_STANDBY:
 530                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 531                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 532                                 return 1;
 533                         case ALUA_ACCESS_STATE_UNAVAILABLE:
 534                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 535                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 536                                 return 1;
 537                         default:
 538                                 break;
 539                         }
 540                 }
 541         }
 542         spin_unlock(&dev->t10_alua.lba_map_lock);
 543         return 0;
 544 }
 545
 546 static inline int core_alua_state_standby(
 547         struct se_cmd *cmd,
 548         unsigned char *cdb)
 549 {
 550         /*
 551          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 552          * spc4r17 section 5.9.2.4.4
 553          */
 554         switch (cdb[0]) {
 555         case INQUIRY:
 556         case LOG_SELECT:
 557         case LOG_SENSE:
 558         case MODE_SELECT:
 559         case MODE_SENSE:
 560         case REPORT_LUNS:
 561         case RECEIVE_DIAGNOSTIC:
 562         case SEND_DIAGNOSTIC:
 563         case READ_CAPACITY:
 564                 return 0;
 565         case SERVICE_ACTION_IN_16:
 566                 switch (cdb[1] & 0x1f) {
 567                 case SAI_READ_CAPACITY_16:
 568                         return 0;
 569                 default:
 570                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 571                         return 1;
 572                 }
 573         case MAINTENANCE_IN:
 574                 switch (cdb[1] & 0x1f) {
 575                 case MI_REPORT_TARGET_PGS:
 576                         return 0;
 577                 default:
 578                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 579                         return 1;
 580                 }
 581         case MAINTENANCE_OUT:
 582                 switch (cdb[1]) {
 583                 case MO_SET_TARGET_PGS:
 584                         return 0;
 585                 default:
 586                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 587                         return 1;
 588                 }
 589         case REQUEST_SENSE:
 590         case PERSISTENT_RESERVE_IN:
 591         case PERSISTENT_RESERVE_OUT:
 592         case READ_BUFFER:
 593         case WRITE_BUFFER:
 594                 return 0;
 595         default:
 596                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 597                 return 1;
 598         }
 599
 600         return 0;
 601 }
 602
 603 static inline int core_alua_state_unavailable(
 604         struct se_cmd *cmd,
 605         unsigned char *cdb)
 606 {
 607         /*
 608          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 609          * spc4r17 section 5.9.2.4.5
 610          */
 611         switch (cdb[0]) {
 612         case INQUIRY:
 613         case REPORT_LUNS:
 614                 return 0;
 615         case MAINTENANCE_IN:
 616                 switch (cdb[1] & 0x1f) {
 617                 case MI_REPORT_TARGET_PGS:
 618                         return 0;
 619                 default:
 620                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 621                         return 1;
 622                 }
 623         case MAINTENANCE_OUT:
 624                 switch (cdb[1]) {
 625                 case MO_SET_TARGET_PGS:
 626                         return 0;
 627                 default:
 628                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 629                         return 1;
 630                 }
 631         case REQUEST_SENSE:
 632         case READ_BUFFER:
 633         case WRITE_BUFFER:
 634                 return 0;
 635         default:
 636                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 637                 return 1;
 638         }
 639
 640         return 0;
 641 }
 642
 643 static inline int core_alua_state_transition(
 644         struct se_cmd *cmd,
 645         unsigned char *cdb)
 646 {
 647         /*
 648          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
 649          * spc4r17 section 5.9.2.5
 650          */
 651         switch (cdb[0]) {
 652         case INQUIRY:
 653         case REPORT_LUNS:
 654                 return 0;
 655         case MAINTENANCE_IN:
 656                 switch (cdb[1] & 0x1f) {
 657                 case MI_REPORT_TARGET_PGS:
 658                         return 0;
 659                 default:
 660                         set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 661                         return 1;
 662                 }
 663         case REQUEST_SENSE:
 664         case READ_BUFFER:
 665         case WRITE_BUFFER:
 666                 return 0;
 667         default:
 668                 set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 669                 return 1;
 670         }
 671
 672         return 0;
 673 }
 674
 675 /*
 676  * return 1: Is used to signal LUN not accessible, and check condition/not ready
 677  * return 0: Used to signal success
 678  * return -1: Used to signal failure, and invalid cdb field
 679  */
 680 sense_reason_t
 681 target_alua_state_check(struct se_cmd *cmd)
 682 {
 683         struct se_device *dev = cmd->se_dev;
 684         unsigned char *cdb = cmd->t_task_cdb;
 685         struct se_lun *lun = cmd->se_lun;
 686         struct t10_alua_tg_pt_gp *tg_pt_gp;
 687         int out_alua_state, nonop_delay_msecs;
 688
 689         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
 690                 return 0;
 691         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
 692                 return 0;
 693
 694         /*
 695          * First, check for a struct se_port specific secondary ALUA target port
 696          * access state: OFFLINE
 697          */
 698         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
 699                 pr_debug("ALUA: Got secondary offline status for local"
 700                                 " target port\n");
 701                 set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
 702                 return TCM_CHECK_CONDITION_NOT_READY;
 703         }
 704
 705         if (!lun->lun_tg_pt_gp)
 706                 return 0;
 707
 708         spin_lock(&lun->lun_tg_pt_gp_lock);
 709         tg_pt_gp = lun->lun_tg_pt_gp;
 710         out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 711         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 712
 713         // XXX: keeps using tg_pt_gp witout reference after unlock
 714         spin_unlock(&lun->lun_tg_pt_gp_lock);
 715         /*
 716          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
 717          * statement so the compiler knows explicitly to check this case first.
 718          * For the Optimized ALUA access state case, we want to process the
 719          * incoming fabric cmd ASAP..
 720          */
 721         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
 722                 return 0;
 723
 724         switch (out_alua_state) {
 725         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 726                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
 727                 break;
 728         case ALUA_ACCESS_STATE_STANDBY:
 729                 if (core_alua_state_standby(cmd, cdb))
 730                         return TCM_CHECK_CONDITION_NOT_READY;
 731                 break;
 732         case ALUA_ACCESS_STATE_UNAVAILABLE:
 733                 if (core_alua_state_unavailable(cmd, cdb))
 734                         return TCM_CHECK_CONDITION_NOT_READY;
 735                 break;
 736         case ALUA_ACCESS_STATE_TRANSITION:
 737                 if (core_alua_state_transition(cmd, cdb))
 738                         return TCM_CHECK_CONDITION_NOT_READY;
 739                 break;
 740         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 741                 if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
 742                         return TCM_CHECK_CONDITION_NOT_READY;
 743                 break;
 744         /*
 745          * OFFLINE is a secondary ALUA target port group access state, that is
 746          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
 747          */
 748         case ALUA_ACCESS_STATE_OFFLINE:
 749         default:
 750                 pr_err("Unknown ALUA access state: 0x%02x\n",
 751                                 out_alua_state);
 752                 return TCM_INVALID_CDB_FIELD;
 753         }
 754
 755         return 0;
 756 }
 757
 758 /*
 759  * Check implicit and explicit ALUA state change request.
 760  */
 761 static sense_reason_t
 762 core_alua_check_transition(int state, int valid, int *primary)
 763 {
 764         /*
 765          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 766          * defined as primary target port asymmetric access states.
 767          */
 768         switch (state) {
 769         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 770                 if (!(valid & ALUA_AO_SUP))
 771                         goto not_supported;
 772                 *primary = 1;
 773                 break;
 774         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 775                 if (!(valid & ALUA_AN_SUP))
 776                         goto not_supported;
 777                 *primary = 1;
 778                 break;
 779         case ALUA_ACCESS_STATE_STANDBY:
 780                 if (!(valid & ALUA_S_SUP))
 781                         goto not_supported;
 782                 *primary = 1;
 783                 break;
 784         case ALUA_ACCESS_STATE_UNAVAILABLE:
 785                 if (!(valid & ALUA_U_SUP))
 786                         goto not_supported;
 787                 *primary = 1;
 788                 break;
 789         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 790                 if (!(valid & ALUA_LBD_SUP))
 791                         goto not_supported;
 792                 *primary = 1;
 793                 break;
 794         case ALUA_ACCESS_STATE_OFFLINE:
 795                 /*
 796                  * OFFLINE state is defined as a secondary target port
 797                  * asymmetric access state.
 798                  */
 799                 if (!(valid & ALUA_O_SUP))
 800                         goto not_supported;
 801                 *primary = 0;
 802                 break;
 803         case ALUA_ACCESS_STATE_TRANSITION:
 804                 /*
 805                  * Transitioning is set internally, and
 806                  * cannot be selected manually.
 807                  */
 808                 goto not_supported;
 809         default:
 810                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 811                 return TCM_INVALID_PARAMETER_LIST;
 812         }
 813
 814         return 0;
 815
 816 not_supported:
 817         pr_err("ALUA access state %s not supported",
 818                core_alua_dump_state(state));
 819         return TCM_INVALID_PARAMETER_LIST;
 820 }
 821
 822 static char *core_alua_dump_state(int state)
 823 {
 824         switch (state) {
 825         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 826                 return "Active/Optimized";
 827         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 828                 return "Active/NonOptimized";
 829         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 830                 return "LBA Dependent";
 831         case ALUA_ACCESS_STATE_STANDBY:
 832                 return "Standby";
 833         case ALUA_ACCESS_STATE_UNAVAILABLE:
 834                 return "Unavailable";
 835         case ALUA_ACCESS_STATE_OFFLINE:
 836                 return "Offline";
 837         case ALUA_ACCESS_STATE_TRANSITION:
 838                 return "Transitioning";
 839         default:
 840                 return "Unknown";
 841         }
 842
 843         return NULL;
 844 }
 845
 846 char *core_alua_dump_status(int status)
 847 {
 848         switch (status) {
 849         case ALUA_STATUS_NONE:
 850                 return "None";
 851         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
 852                 return "Altered by Explicit STPG";
 853         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
 854                 return "Altered by Implicit ALUA";
 855         default:
 856                 return "Unknown";
 857         }
 858
 859         return NULL;
 860 }
 861
 862 /*
 863  * Used by fabric modules to determine when we need to delay processing
 864  * for the Active/NonOptimized paths..
 865  */
 866 int core_alua_check_nonop_delay(
 867         struct se_cmd *cmd)
 868 {
 869         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 870                 return 0;
 871         if (in_interrupt())
 872                 return 0;
 873         /*
 874          * The ALUA Active/NonOptimized access state delay can be disabled
 875          * in via configfs with a value of zero
 876          */
 877         if (!cmd->alua_nonop_delay)
 878                 return 0;
 879         /*
 880          * struct se_cmd->alua_nonop_delay gets set by a target port group
 881          * defined interval in core_alua_state_nonoptimized()
 882          */
 883         msleep_interruptible(cmd->alua_nonop_delay);
 884         return 0;
 885 }
 886 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 887
 888 static int core_alua_write_tpg_metadata(
 889         const char *path,
 890         unsigned char *md_buf,
 891         u32 md_buf_len)
 892 {
 893         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
 894         int ret;
 895
 896         if (IS_ERR(file)) {
 897                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
 898                 return -ENODEV;
 899         }
 900         ret = kernel_write(file, md_buf, md_buf_len, 0);
 901         if (ret < 0)
 902                 pr_err("Error writing ALUA metadata file: %s\n", path);
 903         fput(file);
 904         return (ret < 0) ? -EIO : 0;
 905 }
 906
 907 /*
 908  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
 909  */
 910 static int core_alua_update_tpg_primary_metadata(
 911         struct t10_alua_tg_pt_gp *tg_pt_gp)
 912 {
 913         unsigned char *md_buf;
 914         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
 915         char path[ALUA_METADATA_PATH_LEN];
 916         int len, rc;
 917
 918         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
 919         if (!md_buf) {
 920                 pr_err("Unable to allocate buf for ALUA metadata\n");
 921                 return -ENOMEM;
 922         }
 923
 924         memset(path, 0, ALUA_METADATA_PATH_LEN);
 925
 926         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
 927                         "tg_pt_gp_id=%hu\n"
 928                         "alua_access_state=0x%02x\n"
 929                         "alua_access_status=0x%02x\n",
 930                         tg_pt_gp->tg_pt_gp_id,
 931                         tg_pt_gp->tg_pt_gp_alua_pending_state,
 932                         tg_pt_gp->tg_pt_gp_alua_access_status);
 933
 934         snprintf(path, ALUA_METADATA_PATH_LEN,
 935                 "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
 936                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 937
 938         rc = core_alua_write_tpg_metadata(path, md_buf, len);
 939         kfree(md_buf);
 940         return rc;
 941 }
 942
 943 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
 944 {
 945         struct se_dev_entry *se_deve;
 946         struct se_lun *lun;
 947         struct se_lun_acl *lacl;
 948
 949         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 950         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 951                                 lun_tg_pt_gp_link) {
 952                 /*
 953                  * After an implicit target port asymmetric access state
 954                  * change, a device server shall establish a unit attention
 955                  * condition for the initiator port associated with every I_T
 956                  * nexus with the additional sense code set to ASYMMETRIC
 957                  * ACCESS STATE CHANGED.
 958                  *
 959                  * After an explicit target port asymmetric access state
 960                  * change, a device server shall establish a unit attention
 961                  * condition with the additional sense code set to ASYMMETRIC
 962                  * ACCESS STATE CHANGED for the initiator port associated with
 963                  * every I_T nexus other than the I_T nexus on which the SET
 964                  * TARGET PORT GROUPS command
 965                  */
 966                 if (!percpu_ref_tryget_live(&lun->lun_ref))
 967                         continue;
 968                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 969
 970                 spin_lock(&lun->lun_deve_lock);
 971                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
 972                         lacl = rcu_dereference_check(se_deve->se_lun_acl,
 973                                         lockdep_is_held(&lun->lun_deve_lock));
 974
 975                         /*
 976                          * spc4r37 p.242:
 977                          * After an explicit target port asymmetric access
 978                          * state change, a device server shall establish a
 979                          * unit attention condition with the additional sense
 980                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
 981                          * the initiator port associated with every I_T nexus
 982                          * other than the I_T nexus on which the SET TARGET
 983                          * PORT GROUPS command was received.
 984                          */
 985                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
 986                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
 987                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
 988                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
 989                                 continue;
 990
 991                         /*
 992                          * se_deve->se_lun_acl pointer may be NULL for a
 993                          * entry created without explicit Node+MappedLUN ACLs
 994                          */
 995                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
 996                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
 997                                 continue;
 998
 999                         core_scsi3_ua_allocate(se_deve, 0x2A,
1000                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1001                 }
1002                 spin_unlock(&lun->lun_deve_lock);
1003
1004                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1005                 percpu_ref_put(&lun->lun_ref);
1006         }
1007         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1008 }
1009
1010 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
1011 {
1012         struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
1013                 struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work.work);
1014         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1015         bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
1016                          ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
1017
1018         /*
1019          * Update the ALUA metadata buf that has been allocated in
1020          * core_alua_do_port_transition(), this metadata will be written
1021          * to struct file.
1022          *
1023          * Note that there is the case where we do not want to update the
1024          * metadata when the saved metadata is being parsed in userspace
1025          * when setting the existing port access state and access status.
1026          *
1027          * Also note that the failure to write out the ALUA metadata to
1028          * struct file does NOT affect the actual ALUA transition.
1029          */
1030         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1031                 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1032                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1033                 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1034         }
1035         /*
1036          * Set the current primary ALUA access state to the requested new state
1037          */
1038         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1039                    tg_pt_gp->tg_pt_gp_alua_pending_state);
1040
1041         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1042                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1043                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1044                 tg_pt_gp->tg_pt_gp_id,
1045                 core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1046                 core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1047
1048         core_alua_queue_state_change_ua(tg_pt_gp);
1049
1050         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1051         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1052         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1053
1054         if (tg_pt_gp->tg_pt_gp_transition_complete)
1055                 complete(tg_pt_gp->tg_pt_gp_transition_complete);
1056 }
1057
1058 static int core_alua_do_transition_tg_pt(
1059         struct t10_alua_tg_pt_gp *tg_pt_gp,
1060         int new_state,
1061         int explicit)
1062 {
1063         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1064         DECLARE_COMPLETION_ONSTACK(wait);
1065
1066         /* Nothing to be done here */
1067         if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1068                 return 0;
1069
1070         if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1071                 return -EAGAIN;
1072
1073         /*
1074          * Flush any pending transitions
1075          */
1076         if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs &&
1077             atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
1078             ALUA_ACCESS_STATE_TRANSITION) {
1079                 /* Just in case */
1080                 tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1081                 tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1082                 flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1083                 wait_for_completion(&wait);
1084                 tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1085                 return 0;
1086         }
1087
1088         /*
1089          * Save the old primary ALUA access state, and set the current state
1090          * to ALUA_ACCESS_STATE_TRANSITION.
1091          */
1092         tg_pt_gp->tg_pt_gp_alua_previous_state =
1093                 atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1094         tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1095
1096         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1097                         ALUA_ACCESS_STATE_TRANSITION);
1098         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1099                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1100                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1101
1102         core_alua_queue_state_change_ua(tg_pt_gp);
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         if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs) {
1118                 unsigned long transition_tmo;
1119
1120                 transition_tmo = tg_pt_gp->tg_pt_gp_implicit_trans_secs * HZ;
1121                 queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1122                                    &tg_pt_gp->tg_pt_gp_transition_work,
1123                                    transition_tmo);
1124         } else {
1125                 tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1126                 queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1127                                    &tg_pt_gp->tg_pt_gp_transition_work, 0);
1128                 wait_for_completion(&wait);
1129                 tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1130         }
1131
1132         return 0;
1133 }
1134
1135 int core_alua_do_port_transition(
1136         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1137         struct se_device *l_dev,
1138         struct se_lun *l_lun,
1139         struct se_node_acl *l_nacl,
1140         int new_state,
1141         int explicit)
1142 {
1143         struct se_device *dev;
1144         struct t10_alua_lu_gp *lu_gp;
1145         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1146         struct t10_alua_tg_pt_gp *tg_pt_gp;
1147         int primary, valid_states, rc = 0;
1148
1149         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1150         if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1151                 return -EINVAL;
1152
1153         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1154         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1155         lu_gp = local_lu_gp_mem->lu_gp;
1156         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1157         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1158         /*
1159          * For storage objects that are members of the 'default_lu_gp',
1160          * we only do transition on the passed *l_tp_pt_gp, and not
1161          * on all of the matching target port groups IDs in default_lu_gp.
1162          */
1163         if (!lu_gp->lu_gp_id) {
1164                 /*
1165                  * core_alua_do_transition_tg_pt() will always return
1166                  * success.
1167                  */
1168                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1169                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1170                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1171                                                    new_state, explicit);
1172                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1173                 return rc;
1174         }
1175         /*
1176          * For all other LU groups aside from 'default_lu_gp', walk all of
1177          * the associated storage objects looking for a matching target port
1178          * group ID from the local target port group.
1179          */
1180         spin_lock(&lu_gp->lu_gp_lock);
1181         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1182                                 lu_gp_mem_list) {
1183
1184                 dev = lu_gp_mem->lu_gp_mem_dev;
1185                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1186                 spin_unlock(&lu_gp->lu_gp_lock);
1187
1188                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1189                 list_for_each_entry(tg_pt_gp,
1190                                 &dev->t10_alua.tg_pt_gps_list,
1191                                 tg_pt_gp_list) {
1192
1193                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1194                                 continue;
1195                         /*
1196                          * If the target behavior port asymmetric access state
1197                          * is changed for any target port group accessible via
1198                          * a logical unit within a LU group, the target port
1199                          * behavior group asymmetric access states for the same
1200                          * target port group accessible via other logical units
1201                          * in that LU group will also change.
1202                          */
1203                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1204                                 continue;
1205
1206                         if (l_tg_pt_gp == tg_pt_gp) {
1207                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1208                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1209                         } else {
1210                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1211                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1212                         }
1213                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1214                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1215                         /*
1216                          * core_alua_do_transition_tg_pt() will always return
1217                          * success.
1218                          */
1219                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1220                                         new_state, explicit);
1221
1222                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1223                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1224                         if (rc)
1225                                 break;
1226                 }
1227                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1228
1229                 spin_lock(&lu_gp->lu_gp_lock);
1230                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1231         }
1232         spin_unlock(&lu_gp->lu_gp_lock);
1233
1234         if (!rc) {
1235                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1236                          " Group IDs: %hu %s transition to primary state: %s\n",
1237                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1238                          l_tg_pt_gp->tg_pt_gp_id,
1239                          (explicit) ? "explicit" : "implicit",
1240                          core_alua_dump_state(new_state));
1241         }
1242
1243         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1244         return rc;
1245 }
1246
1247 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1248 {
1249         struct se_portal_group *se_tpg = lun->lun_tpg;
1250         unsigned char *md_buf;
1251         char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1252         int len, rc;
1253
1254         mutex_lock(&lun->lun_tg_pt_md_mutex);
1255
1256         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1257         if (!md_buf) {
1258                 pr_err("Unable to allocate buf for ALUA metadata\n");
1259                 rc = -ENOMEM;
1260                 goto out_unlock;
1261         }
1262
1263         memset(path, 0, ALUA_METADATA_PATH_LEN);
1264         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1265
1266         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1267                         se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1268
1269         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1270                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1271                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1272
1273         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1274                         "alua_tg_pt_status=0x%02x\n",
1275                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1276                         lun->lun_tg_pt_secondary_stat);
1277
1278         snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%llu",
1279                         se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1280                         lun->unpacked_lun);
1281
1282         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1283         kfree(md_buf);
1284
1285 out_unlock:
1286         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1287         return rc;
1288 }
1289
1290 static int core_alua_set_tg_pt_secondary_state(
1291         struct se_lun *lun,
1292         int explicit,
1293         int offline)
1294 {
1295         struct t10_alua_tg_pt_gp *tg_pt_gp;
1296         int trans_delay_msecs;
1297
1298         spin_lock(&lun->lun_tg_pt_gp_lock);
1299         tg_pt_gp = lun->lun_tg_pt_gp;
1300         if (!tg_pt_gp) {
1301                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1302                 pr_err("Unable to complete secondary state"
1303                                 " transition\n");
1304                 return -EINVAL;
1305         }
1306         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1307         /*
1308          * Set the secondary ALUA target port access state to OFFLINE
1309          * or release the previously secondary state for struct se_lun
1310          */
1311         if (offline)
1312                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1313         else
1314                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1315
1316         lun->lun_tg_pt_secondary_stat = (explicit) ?
1317                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1318                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1319
1320         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1321                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1322                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1323                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1324
1325         spin_unlock(&lun->lun_tg_pt_gp_lock);
1326         /*
1327          * Do the optional transition delay after we set the secondary
1328          * ALUA access state.
1329          */
1330         if (trans_delay_msecs != 0)
1331                 msleep_interruptible(trans_delay_msecs);
1332         /*
1333          * See if we need to update the ALUA fabric port metadata for
1334          * secondary state and status
1335          */
1336         if (lun->lun_tg_pt_secondary_write_md)
1337                 core_alua_update_tpg_secondary_metadata(lun);
1338
1339         return 0;
1340 }
1341
1342 struct t10_alua_lba_map *
1343 core_alua_allocate_lba_map(struct list_head *list,
1344                            u64 first_lba, u64 last_lba)
1345 {
1346         struct t10_alua_lba_map *lba_map;
1347
1348         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1349         if (!lba_map) {
1350                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1351                 return ERR_PTR(-ENOMEM);
1352         }
1353         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1354         lba_map->lba_map_first_lba = first_lba;
1355         lba_map->lba_map_last_lba = last_lba;
1356
1357         list_add_tail(&lba_map->lba_map_list, list);
1358         return lba_map;
1359 }
1360
1361 int
1362 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1363                                int pg_id, int state)
1364 {
1365         struct t10_alua_lba_map_member *lba_map_mem;
1366
1367         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1368                             lba_map_mem_list) {
1369                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1370                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1371                         return -EINVAL;
1372                 }
1373         }
1374
1375         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1376         if (!lba_map_mem) {
1377                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1378                 return -ENOMEM;
1379         }
1380         lba_map_mem->lba_map_mem_alua_state = state;
1381         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1382
1383         list_add_tail(&lba_map_mem->lba_map_mem_list,
1384                       &lba_map->lba_map_mem_list);
1385         return 0;
1386 }
1387
1388 void
1389 core_alua_free_lba_map(struct list_head *lba_list)
1390 {
1391         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1392         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1393
1394         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1395                                  lba_map_list) {
1396                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1397                                          &lba_map->lba_map_mem_list,
1398                                          lba_map_mem_list) {
1399                         list_del(&lba_map_mem->lba_map_mem_list);
1400                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1401                                         lba_map_mem);
1402                 }
1403                 list_del(&lba_map->lba_map_list);
1404                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1405         }
1406 }
1407
1408 void
1409 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1410                       int segment_size, int segment_mult)
1411 {
1412         struct list_head old_lba_map_list;
1413         struct t10_alua_tg_pt_gp *tg_pt_gp;
1414         int activate = 0, supported;
1415
1416         INIT_LIST_HEAD(&old_lba_map_list);
1417         spin_lock(&dev->t10_alua.lba_map_lock);
1418         dev->t10_alua.lba_map_segment_size = segment_size;
1419         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1420         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1421         if (lba_map_list) {
1422                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1423                 activate = 1;
1424         }
1425         spin_unlock(&dev->t10_alua.lba_map_lock);
1426         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1427         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1428                             tg_pt_gp_list) {
1429
1430                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1431                         continue;
1432                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1433                 if (activate)
1434                         supported |= ALUA_LBD_SUP;
1435                 else
1436                         supported &= ~ALUA_LBD_SUP;
1437                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1438         }
1439         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1440         core_alua_free_lba_map(&old_lba_map_list);
1441 }
1442
1443 struct t10_alua_lu_gp *
1444 core_alua_allocate_lu_gp(const char *name, int def_group)
1445 {
1446         struct t10_alua_lu_gp *lu_gp;
1447
1448         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1449         if (!lu_gp) {
1450                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1451                 return ERR_PTR(-ENOMEM);
1452         }
1453         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1454         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1455         spin_lock_init(&lu_gp->lu_gp_lock);
1456         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1457
1458         if (def_group) {
1459                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1460                 lu_gp->lu_gp_valid_id = 1;
1461                 alua_lu_gps_count++;
1462         }
1463
1464         return lu_gp;
1465 }
1466
1467 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1468 {
1469         struct t10_alua_lu_gp *lu_gp_tmp;
1470         u16 lu_gp_id_tmp;
1471         /*
1472          * The lu_gp->lu_gp_id may only be set once..
1473          */
1474         if (lu_gp->lu_gp_valid_id) {
1475                 pr_warn("ALUA LU Group already has a valid ID,"
1476                         " ignoring request\n");
1477                 return -EINVAL;
1478         }
1479
1480         spin_lock(&lu_gps_lock);
1481         if (alua_lu_gps_count == 0x0000ffff) {
1482                 pr_err("Maximum ALUA alua_lu_gps_count:"
1483                                 " 0x0000ffff reached\n");
1484                 spin_unlock(&lu_gps_lock);
1485                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1486                 return -ENOSPC;
1487         }
1488 again:
1489         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1490                                 alua_lu_gps_counter++;
1491
1492         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1493                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1494                         if (!lu_gp_id)
1495                                 goto again;
1496
1497                         pr_warn("ALUA Logical Unit Group ID: %hu"
1498                                 " already exists, ignoring request\n",
1499                                 lu_gp_id);
1500                         spin_unlock(&lu_gps_lock);
1501                         return -EINVAL;
1502                 }
1503         }
1504
1505         lu_gp->lu_gp_id = lu_gp_id_tmp;
1506         lu_gp->lu_gp_valid_id = 1;
1507         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1508         alua_lu_gps_count++;
1509         spin_unlock(&lu_gps_lock);
1510
1511         return 0;
1512 }
1513
1514 static struct t10_alua_lu_gp_member *
1515 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1516 {
1517         struct t10_alua_lu_gp_member *lu_gp_mem;
1518
1519         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1520         if (!lu_gp_mem) {
1521                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1522                 return ERR_PTR(-ENOMEM);
1523         }
1524         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1525         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1526         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1527
1528         lu_gp_mem->lu_gp_mem_dev = dev;
1529         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1530
1531         return lu_gp_mem;
1532 }
1533
1534 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1535 {
1536         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1537         /*
1538          * Once we have reached this point, config_item_put() has
1539          * already been called from target_core_alua_drop_lu_gp().
1540          *
1541          * Here, we remove the *lu_gp from the global list so that
1542          * no associations can be made while we are releasing
1543          * struct t10_alua_lu_gp.
1544          */
1545         spin_lock(&lu_gps_lock);
1546         list_del(&lu_gp->lu_gp_node);
1547         alua_lu_gps_count--;
1548         spin_unlock(&lu_gps_lock);
1549         /*
1550          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1551          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1552          * released with core_alua_put_lu_gp_from_name()
1553          */
1554         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1555                 cpu_relax();
1556         /*
1557          * Release reference to struct t10_alua_lu_gp * from all associated
1558          * struct se_device.
1559          */
1560         spin_lock(&lu_gp->lu_gp_lock);
1561         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1562                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1563                 if (lu_gp_mem->lu_gp_assoc) {
1564                         list_del(&lu_gp_mem->lu_gp_mem_list);
1565                         lu_gp->lu_gp_members--;
1566                         lu_gp_mem->lu_gp_assoc = 0;
1567                 }
1568                 spin_unlock(&lu_gp->lu_gp_lock);
1569                 /*
1570                  *
1571                  * lu_gp_mem is associated with a single
1572                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1573                  * struct se_device is released via core_alua_free_lu_gp_mem().
1574                  *
1575                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1576                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1577                  */
1578                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1579                 if (lu_gp != default_lu_gp)
1580                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1581                                         default_lu_gp);
1582                 else
1583                         lu_gp_mem->lu_gp = NULL;
1584                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1585
1586                 spin_lock(&lu_gp->lu_gp_lock);
1587         }
1588         spin_unlock(&lu_gp->lu_gp_lock);
1589
1590         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1591 }
1592
1593 void core_alua_free_lu_gp_mem(struct se_device *dev)
1594 {
1595         struct t10_alua_lu_gp *lu_gp;
1596         struct t10_alua_lu_gp_member *lu_gp_mem;
1597
1598         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1599         if (!lu_gp_mem)
1600                 return;
1601
1602         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1603                 cpu_relax();
1604
1605         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1606         lu_gp = lu_gp_mem->lu_gp;
1607         if (lu_gp) {
1608                 spin_lock(&lu_gp->lu_gp_lock);
1609                 if (lu_gp_mem->lu_gp_assoc) {
1610                         list_del(&lu_gp_mem->lu_gp_mem_list);
1611                         lu_gp->lu_gp_members--;
1612                         lu_gp_mem->lu_gp_assoc = 0;
1613                 }
1614                 spin_unlock(&lu_gp->lu_gp_lock);
1615                 lu_gp_mem->lu_gp = NULL;
1616         }
1617         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1618
1619         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1620 }
1621
1622 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1623 {
1624         struct t10_alua_lu_gp *lu_gp;
1625         struct config_item *ci;
1626
1627         spin_lock(&lu_gps_lock);
1628         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1629                 if (!lu_gp->lu_gp_valid_id)
1630                         continue;
1631                 ci = &lu_gp->lu_gp_group.cg_item;
1632                 if (!strcmp(config_item_name(ci), name)) {
1633                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1634                         spin_unlock(&lu_gps_lock);
1635                         return lu_gp;
1636                 }
1637         }
1638         spin_unlock(&lu_gps_lock);
1639
1640         return NULL;
1641 }
1642
1643 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1644 {
1645         spin_lock(&lu_gps_lock);
1646         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1647         spin_unlock(&lu_gps_lock);
1648 }
1649
1650 /*
1651  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1652  */
1653 void __core_alua_attach_lu_gp_mem(
1654         struct t10_alua_lu_gp_member *lu_gp_mem,
1655         struct t10_alua_lu_gp *lu_gp)
1656 {
1657         spin_lock(&lu_gp->lu_gp_lock);
1658         lu_gp_mem->lu_gp = lu_gp;
1659         lu_gp_mem->lu_gp_assoc = 1;
1660         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1661         lu_gp->lu_gp_members++;
1662         spin_unlock(&lu_gp->lu_gp_lock);
1663 }
1664
1665 /*
1666  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1667  */
1668 void __core_alua_drop_lu_gp_mem(
1669         struct t10_alua_lu_gp_member *lu_gp_mem,
1670         struct t10_alua_lu_gp *lu_gp)
1671 {
1672         spin_lock(&lu_gp->lu_gp_lock);
1673         list_del(&lu_gp_mem->lu_gp_mem_list);
1674         lu_gp_mem->lu_gp = NULL;
1675         lu_gp_mem->lu_gp_assoc = 0;
1676         lu_gp->lu_gp_members--;
1677         spin_unlock(&lu_gp->lu_gp_lock);
1678 }
1679
1680 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1681                 const char *name, int def_group)
1682 {
1683         struct t10_alua_tg_pt_gp *tg_pt_gp;
1684
1685         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1686         if (!tg_pt_gp) {
1687                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1688                 return NULL;
1689         }
1690         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1691         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1692         mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1693         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1694         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1695         INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1696                           core_alua_do_transition_tg_pt_work);
1697         tg_pt_gp->tg_pt_gp_dev = dev;
1698         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1699                 ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1700         /*
1701          * Enable both explicit and implicit ALUA support by default
1702          */
1703         tg_pt_gp->tg_pt_gp_alua_access_type =
1704                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1705         /*
1706          * Set the default Active/NonOptimized Delay in milliseconds
1707          */
1708         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1709         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1710         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1711
1712         /*
1713          * Enable all supported states
1714          */
1715         tg_pt_gp->tg_pt_gp_alua_supported_states =
1716             ALUA_T_SUP | ALUA_O_SUP |
1717             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1718
1719         if (def_group) {
1720                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1721                 tg_pt_gp->tg_pt_gp_id =
1722                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1723                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1724                 dev->t10_alua.alua_tg_pt_gps_count++;
1725                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1726                               &dev->t10_alua.tg_pt_gps_list);
1727                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1728         }
1729
1730         return tg_pt_gp;
1731 }
1732
1733 int core_alua_set_tg_pt_gp_id(
1734         struct t10_alua_tg_pt_gp *tg_pt_gp,
1735         u16 tg_pt_gp_id)
1736 {
1737         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1738         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1739         u16 tg_pt_gp_id_tmp;
1740
1741         /*
1742          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1743          */
1744         if (tg_pt_gp->tg_pt_gp_valid_id) {
1745                 pr_warn("ALUA TG PT Group already has a valid ID,"
1746                         " ignoring request\n");
1747                 return -EINVAL;
1748         }
1749
1750         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1751         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1752                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1753                         " 0x0000ffff reached\n");
1754                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1755                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1756                 return -ENOSPC;
1757         }
1758 again:
1759         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1760                         dev->t10_alua.alua_tg_pt_gps_counter++;
1761
1762         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1763                         tg_pt_gp_list) {
1764                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1765                         if (!tg_pt_gp_id)
1766                                 goto again;
1767
1768                         pr_err("ALUA Target Port Group ID: %hu already"
1769                                 " exists, ignoring request\n", tg_pt_gp_id);
1770                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1771                         return -EINVAL;
1772                 }
1773         }
1774
1775         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1776         tg_pt_gp->tg_pt_gp_valid_id = 1;
1777         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1778                         &dev->t10_alua.tg_pt_gps_list);
1779         dev->t10_alua.alua_tg_pt_gps_count++;
1780         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1781
1782         return 0;
1783 }
1784
1785 void core_alua_free_tg_pt_gp(
1786         struct t10_alua_tg_pt_gp *tg_pt_gp)
1787 {
1788         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1789         struct se_lun *lun, *next;
1790
1791         /*
1792          * Once we have reached this point, config_item_put() has already
1793          * been called from target_core_alua_drop_tg_pt_gp().
1794          *
1795          * Here we remove *tg_pt_gp from the global list so that
1796          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1797          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1798          */
1799         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1800         list_del(&tg_pt_gp->tg_pt_gp_list);
1801         dev->t10_alua.alua_tg_pt_gps_counter--;
1802         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1803
1804         flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1805
1806         /*
1807          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1808          * core_alua_get_tg_pt_gp_by_name() in
1809          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1810          * to be released with core_alua_put_tg_pt_gp_from_name().
1811          */
1812         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1813                 cpu_relax();
1814
1815         /*
1816          * Release reference to struct t10_alua_tg_pt_gp from all associated
1817          * struct se_port.
1818          */
1819         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1820         list_for_each_entry_safe(lun, next,
1821                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1822                 list_del_init(&lun->lun_tg_pt_gp_link);
1823                 tg_pt_gp->tg_pt_gp_members--;
1824
1825                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1826                 /*
1827                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1828                  * assume we want to re-associate a given tg_pt_gp_mem with
1829                  * default_tg_pt_gp.
1830                  */
1831                 spin_lock(&lun->lun_tg_pt_gp_lock);
1832                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1833                         __target_attach_tg_pt_gp(lun,
1834                                         dev->t10_alua.default_tg_pt_gp);
1835                 } else
1836                         lun->lun_tg_pt_gp = NULL;
1837                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1838
1839                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1840         }
1841         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1842
1843         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1844 }
1845
1846 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1847                 struct se_device *dev, const char *name)
1848 {
1849         struct t10_alua_tg_pt_gp *tg_pt_gp;
1850         struct config_item *ci;
1851
1852         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1853         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1854                         tg_pt_gp_list) {
1855                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1856                         continue;
1857                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1858                 if (!strcmp(config_item_name(ci), name)) {
1859                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1860                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1861                         return tg_pt_gp;
1862                 }
1863         }
1864         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1865
1866         return NULL;
1867 }
1868
1869 static void core_alua_put_tg_pt_gp_from_name(
1870         struct t10_alua_tg_pt_gp *tg_pt_gp)
1871 {
1872         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1873
1874         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1875         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1876         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1877 }
1878
1879 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1880                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1881 {
1882         struct se_dev_entry *se_deve;
1883
1884         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1885
1886         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1887         lun->lun_tg_pt_gp = tg_pt_gp;
1888         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1889         tg_pt_gp->tg_pt_gp_members++;
1890         spin_lock(&lun->lun_deve_lock);
1891         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1892                 core_scsi3_ua_allocate(se_deve, 0x3f,
1893                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1894         spin_unlock(&lun->lun_deve_lock);
1895         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1896 }
1897
1898 void target_attach_tg_pt_gp(struct se_lun *lun,
1899                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1900 {
1901         spin_lock(&lun->lun_tg_pt_gp_lock);
1902         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1903         spin_unlock(&lun->lun_tg_pt_gp_lock);
1904 }
1905
1906 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1907                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1908 {
1909         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1910
1911         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1912         list_del_init(&lun->lun_tg_pt_gp_link);
1913         tg_pt_gp->tg_pt_gp_members--;
1914         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1915
1916         lun->lun_tg_pt_gp = NULL;
1917 }
1918
1919 void target_detach_tg_pt_gp(struct se_lun *lun)
1920 {
1921         struct t10_alua_tg_pt_gp *tg_pt_gp;
1922
1923         spin_lock(&lun->lun_tg_pt_gp_lock);
1924         tg_pt_gp = lun->lun_tg_pt_gp;
1925         if (tg_pt_gp)
1926                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1927         spin_unlock(&lun->lun_tg_pt_gp_lock);
1928 }
1929
1930 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1931 {
1932         struct config_item *tg_pt_ci;
1933         struct t10_alua_tg_pt_gp *tg_pt_gp;
1934         ssize_t len = 0;
1935
1936         spin_lock(&lun->lun_tg_pt_gp_lock);
1937         tg_pt_gp = lun->lun_tg_pt_gp;
1938         if (tg_pt_gp) {
1939                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1940                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1941                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1942                         "Primary Access Status: %s\nTG Port Secondary Access"
1943                         " State: %s\nTG Port Secondary Access Status: %s\n",
1944                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1945                         core_alua_dump_state(atomic_read(
1946                                         &tg_pt_gp->tg_pt_gp_alua_access_state)),
1947                         core_alua_dump_status(
1948                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1949                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1950                         "Offline" : "None",
1951                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1952         }
1953         spin_unlock(&lun->lun_tg_pt_gp_lock);
1954
1955         return len;
1956 }
1957
1958 ssize_t core_alua_store_tg_pt_gp_info(
1959         struct se_lun *lun,
1960         const char *page,
1961         size_t count)
1962 {
1963         struct se_portal_group *tpg = lun->lun_tpg;
1964         /*
1965          * rcu_dereference_raw protected by se_lun->lun_group symlink
1966          * reference to se_device->dev_group.
1967          */
1968         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1969         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1970         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1971         int move = 0;
1972
1973         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH ||
1974             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1975                 return -ENODEV;
1976
1977         if (count > TG_PT_GROUP_NAME_BUF) {
1978                 pr_err("ALUA Target Port Group alias too large!\n");
1979                 return -EINVAL;
1980         }
1981         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1982         memcpy(buf, page, count);
1983         /*
1984          * Any ALUA target port group alias besides "NULL" means we will be
1985          * making a new group association.
1986          */
1987         if (strcmp(strstrip(buf), "NULL")) {
1988                 /*
1989                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1990                  * struct t10_alua_tg_pt_gp.  This reference is released with
1991                  * core_alua_put_tg_pt_gp_from_name() below.
1992                  */
1993                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1994                                         strstrip(buf));
1995                 if (!tg_pt_gp_new)
1996                         return -ENODEV;
1997         }
1998
1999         spin_lock(&lun->lun_tg_pt_gp_lock);
2000         tg_pt_gp = lun->lun_tg_pt_gp;
2001         if (tg_pt_gp) {
2002                 /*
2003                  * Clearing an existing tg_pt_gp association, and replacing
2004                  * with the default_tg_pt_gp.
2005                  */
2006                 if (!tg_pt_gp_new) {
2007                         pr_debug("Target_Core_ConfigFS: Moving"
2008                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
2009                                 " alua/%s, ID: %hu back to"
2010                                 " default_tg_pt_gp\n",
2011                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2012                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
2013                                 config_item_name(&lun->lun_group.cg_item),
2014                                 config_item_name(
2015                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
2016                                 tg_pt_gp->tg_pt_gp_id);
2017
2018                         __target_detach_tg_pt_gp(lun, tg_pt_gp);
2019                         __target_attach_tg_pt_gp(lun,
2020                                         dev->t10_alua.default_tg_pt_gp);
2021                         spin_unlock(&lun->lun_tg_pt_gp_lock);
2022
2023                         return count;
2024                 }
2025                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
2026                 move = 1;
2027         }
2028
2029         __target_attach_tg_pt_gp(lun, tg_pt_gp_new);
2030         spin_unlock(&lun->lun_tg_pt_gp_lock);
2031         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2032                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
2033                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2034                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
2035                 config_item_name(&lun->lun_group.cg_item),
2036                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2037                 tg_pt_gp_new->tg_pt_gp_id);
2038
2039         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2040         return count;
2041 }
2042
2043 ssize_t core_alua_show_access_type(
2044         struct t10_alua_tg_pt_gp *tg_pt_gp,
2045         char *page)
2046 {
2047         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2048             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2049                 return sprintf(page, "Implicit and Explicit\n");
2050         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2051                 return sprintf(page, "Implicit\n");
2052         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2053                 return sprintf(page, "Explicit\n");
2054         else
2055                 return sprintf(page, "None\n");
2056 }
2057
2058 ssize_t core_alua_store_access_type(
2059         struct t10_alua_tg_pt_gp *tg_pt_gp,
2060         const char *page,
2061         size_t count)
2062 {
2063         unsigned long tmp;
2064         int ret;
2065
2066         ret = kstrtoul(page, 0, &tmp);
2067         if (ret < 0) {
2068                 pr_err("Unable to extract alua_access_type\n");
2069                 return ret;
2070         }
2071         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2072                 pr_err("Illegal value for alua_access_type:"
2073                                 " %lu\n", tmp);
2074                 return -EINVAL;
2075         }
2076         if (tmp == 3)
2077                 tg_pt_gp->tg_pt_gp_alua_access_type =
2078                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2079         else if (tmp == 2)
2080                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2081         else if (tmp == 1)
2082                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2083         else
2084                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2085
2086         return count;
2087 }
2088
2089 ssize_t core_alua_show_nonop_delay_msecs(
2090         struct t10_alua_tg_pt_gp *tg_pt_gp,
2091         char *page)
2092 {
2093         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2094 }
2095
2096 ssize_t core_alua_store_nonop_delay_msecs(
2097         struct t10_alua_tg_pt_gp *tg_pt_gp,
2098         const char *page,
2099         size_t count)
2100 {
2101         unsigned long tmp;
2102         int ret;
2103
2104         ret = kstrtoul(page, 0, &tmp);
2105         if (ret < 0) {
2106                 pr_err("Unable to extract nonop_delay_msecs\n");
2107                 return ret;
2108         }
2109         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2110                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2111                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2112                         ALUA_MAX_NONOP_DELAY_MSECS);
2113                 return -EINVAL;
2114         }
2115         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2116
2117         return count;
2118 }
2119
2120 ssize_t core_alua_show_trans_delay_msecs(
2121         struct t10_alua_tg_pt_gp *tg_pt_gp,
2122         char *page)
2123 {
2124         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2125 }
2126
2127 ssize_t core_alua_store_trans_delay_msecs(
2128         struct t10_alua_tg_pt_gp *tg_pt_gp,
2129         const char *page,
2130         size_t count)
2131 {
2132         unsigned long tmp;
2133         int ret;
2134
2135         ret = kstrtoul(page, 0, &tmp);
2136         if (ret < 0) {
2137                 pr_err("Unable to extract trans_delay_msecs\n");
2138                 return ret;
2139         }
2140         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2141                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2142                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2143                         ALUA_MAX_TRANS_DELAY_MSECS);
2144                 return -EINVAL;
2145         }
2146         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2147
2148         return count;
2149 }
2150
2151 ssize_t core_alua_show_implicit_trans_secs(
2152         struct t10_alua_tg_pt_gp *tg_pt_gp,
2153         char *page)
2154 {
2155         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2156 }
2157
2158 ssize_t core_alua_store_implicit_trans_secs(
2159         struct t10_alua_tg_pt_gp *tg_pt_gp,
2160         const char *page,
2161         size_t count)
2162 {
2163         unsigned long tmp;
2164         int ret;
2165
2166         ret = kstrtoul(page, 0, &tmp);
2167         if (ret < 0) {
2168                 pr_err("Unable to extract implicit_trans_secs\n");
2169                 return ret;
2170         }
2171         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2172                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2173                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2174                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2175                 return  -EINVAL;
2176         }
2177         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2178
2179         return count;
2180 }
2181
2182 ssize_t core_alua_show_preferred_bit(
2183         struct t10_alua_tg_pt_gp *tg_pt_gp,
2184         char *page)
2185 {
2186         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2187 }
2188
2189 ssize_t core_alua_store_preferred_bit(
2190         struct t10_alua_tg_pt_gp *tg_pt_gp,
2191         const char *page,
2192         size_t count)
2193 {
2194         unsigned long tmp;
2195         int ret;
2196
2197         ret = kstrtoul(page, 0, &tmp);
2198         if (ret < 0) {
2199                 pr_err("Unable to extract preferred ALUA value\n");
2200                 return ret;
2201         }
2202         if ((tmp != 0) && (tmp != 1)) {
2203                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2204                 return -EINVAL;
2205         }
2206         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2207
2208         return count;
2209 }
2210
2211 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2212 {
2213         return sprintf(page, "%d\n",
2214                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2215 }
2216
2217 ssize_t core_alua_store_offline_bit(
2218         struct se_lun *lun,
2219         const char *page,
2220         size_t count)
2221 {
2222         /*
2223          * rcu_dereference_raw protected by se_lun->lun_group symlink
2224          * reference to se_device->dev_group.
2225          */
2226         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2227         unsigned long tmp;
2228         int ret;
2229
2230         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH ||
2231             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2232                 return -ENODEV;
2233
2234         ret = kstrtoul(page, 0, &tmp);
2235         if (ret < 0) {
2236                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2237                 return ret;
2238         }
2239         if ((tmp != 0) && (tmp != 1)) {
2240                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2241                                 tmp);
2242                 return -EINVAL;
2243         }
2244
2245         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2246         if (ret < 0)
2247                 return -EINVAL;
2248
2249         return count;
2250 }
2251
2252 ssize_t core_alua_show_secondary_status(
2253         struct se_lun *lun,
2254         char *page)
2255 {
2256         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2257 }
2258
2259 ssize_t core_alua_store_secondary_status(
2260         struct se_lun *lun,
2261         const char *page,
2262         size_t count)
2263 {
2264         unsigned long tmp;
2265         int ret;
2266
2267         ret = kstrtoul(page, 0, &tmp);
2268         if (ret < 0) {
2269                 pr_err("Unable to extract alua_tg_pt_status\n");
2270                 return ret;
2271         }
2272         if ((tmp != ALUA_STATUS_NONE) &&
2273             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2274             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2275                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2276                                 tmp);
2277                 return -EINVAL;
2278         }
2279         lun->lun_tg_pt_secondary_stat = (int)tmp;
2280
2281         return count;
2282 }
2283
2284 ssize_t core_alua_show_secondary_write_metadata(
2285         struct se_lun *lun,
2286         char *page)
2287 {
2288         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2289 }
2290
2291 ssize_t core_alua_store_secondary_write_metadata(
2292         struct se_lun *lun,
2293         const char *page,
2294         size_t count)
2295 {
2296         unsigned long tmp;
2297         int ret;
2298
2299         ret = kstrtoul(page, 0, &tmp);
2300         if (ret < 0) {
2301                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2302                 return ret;
2303         }
2304         if ((tmp != 0) && (tmp != 1)) {
2305                 pr_err("Illegal value for alua_tg_pt_write_md:"
2306                                 " %lu\n", tmp);
2307                 return -EINVAL;
2308         }
2309         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2310
2311         return count;
2312 }
2313
2314 int core_setup_alua(struct se_device *dev)
2315 {
2316         if (!(dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) &&
2317             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2318                 struct t10_alua_lu_gp_member *lu_gp_mem;
2319
2320                 /*
2321                  * Associate this struct se_device with the default ALUA
2322                  * LUN Group.
2323                  */
2324                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2325                 if (IS_ERR(lu_gp_mem))
2326                         return PTR_ERR(lu_gp_mem);
2327
2328                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2329                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2330                                 default_lu_gp);
2331                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2332
2333                 pr_debug("%s: Adding to default ALUA LU Group:"
2334                         " core/alua/lu_gps/default_lu_gp\n",
2335                         dev->transport->name);
2336         }
2337
2338         return 0;
2339 }