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 <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/slab.h>
  27 #include <linux/spinlock.h>
  28 #include <linux/configfs.h>
  29 #include <linux/delay.h>
  30 #include <linux/export.h>
  31 #include <linux/fcntl.h>
  32 #include <linux/file.h>
  33 #include <linux/fs.h>
  34 #include <scsi/scsi_proto.h>
  35 #include <asm/unaligned.h>
  36
  37 #include <target/target_core_base.h>
  38 #include <target/target_core_backend.h>
  39 #include <target/target_core_fabric.h>
  40
  41 #include "target_core_internal.h"
  42 #include "target_core_alua.h"
  43 #include "target_core_ua.h"
  44
  45 static sense_reason_t core_alua_check_transition(int state, int valid,
  46                                                  int *primary, int explicit);
  47 static int core_alua_set_tg_pt_secondary_state(
  48                 struct se_lun *lun, int explicit, int offline);
  49
  50 static char *core_alua_dump_state(int state);
  51
  52 static void __target_attach_tg_pt_gp(struct se_lun *lun,
  53                 struct t10_alua_tg_pt_gp *tg_pt_gp);
  54
  55 static u16 alua_lu_gps_counter;
  56 static u32 alua_lu_gps_count;
  57
  58 static DEFINE_SPINLOCK(lu_gps_lock);
  59 static LIST_HEAD(lu_gps_list);
  60
  61 struct t10_alua_lu_gp *default_lu_gp;
  62
  63 /*
  64  * REPORT REFERRALS
  65  *
  66  * See sbc3r35 section 5.23
  67  */
  68 sense_reason_t
  69 target_emulate_report_referrals(struct se_cmd *cmd)
  70 {
  71         struct se_device *dev = cmd->se_dev;
  72         struct t10_alua_lba_map *map;
  73         struct t10_alua_lba_map_member *map_mem;
  74         unsigned char *buf;
  75         u32 rd_len = 0, off;
  76
  77         if (cmd->data_length < 4) {
  78                 pr_warn("REPORT REFERRALS allocation length %u too"
  79                         " small\n", cmd->data_length);
  80                 return TCM_INVALID_CDB_FIELD;
  81         }
  82
  83         buf = transport_kmap_data_sg(cmd);
  84         if (!buf)
  85                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
  86
  87         off = 4;
  88         spin_lock(&dev->t10_alua.lba_map_lock);
  89         if (list_empty(&dev->t10_alua.lba_map_list)) {
  90                 spin_unlock(&dev->t10_alua.lba_map_lock);
  91                 transport_kunmap_data_sg(cmd);
  92
  93                 return TCM_UNSUPPORTED_SCSI_OPCODE;
  94         }
  95
  96         list_for_each_entry(map, &dev->t10_alua.lba_map_list,
  97                             lba_map_list) {
  98                 int desc_num = off + 3;
  99                 int pg_num;
 100
 101                 off += 4;
 102                 if (cmd->data_length > off)
 103                         put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
 104                 off += 8;
 105                 if (cmd->data_length > off)
 106                         put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
 107                 off += 8;
 108                 rd_len += 20;
 109                 pg_num = 0;
 110                 list_for_each_entry(map_mem, &map->lba_map_mem_list,
 111                                     lba_map_mem_list) {
 112                         int alua_state = map_mem->lba_map_mem_alua_state;
 113                         int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
 114
 115                         if (cmd->data_length > off)
 116                                 buf[off] = alua_state & 0x0f;
 117                         off += 2;
 118                         if (cmd->data_length > off)
 119                                 buf[off] = (alua_pg_id >> 8) & 0xff;
 120                         off++;
 121                         if (cmd->data_length > off)
 122                                 buf[off] = (alua_pg_id & 0xff);
 123                         off++;
 124                         rd_len += 4;
 125                         pg_num++;
 126                 }
 127                 if (cmd->data_length > desc_num)
 128                         buf[desc_num] = pg_num;
 129         }
 130         spin_unlock(&dev->t10_alua.lba_map_lock);
 131
 132         /*
 133          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 134          */
 135         put_unaligned_be16(rd_len, &buf[2]);
 136
 137         transport_kunmap_data_sg(cmd);
 138
 139         target_complete_cmd(cmd, GOOD);
 140         return 0;
 141 }
 142
 143 /*
 144  * REPORT_TARGET_PORT_GROUPS
 145  *
 146  * See spc4r17 section 6.27
 147  */
 148 sense_reason_t
 149 target_emulate_report_target_port_groups(struct se_cmd *cmd)
 150 {
 151         struct se_device *dev = cmd->se_dev;
 152         struct t10_alua_tg_pt_gp *tg_pt_gp;
 153         struct se_lun *lun;
 154         unsigned char *buf;
 155         u32 rd_len = 0, off;
 156         int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
 157
 158         /*
 159          * Skip over RESERVED area to first Target port group descriptor
 160          * depending on the PARAMETER DATA FORMAT type..
 161          */
 162         if (ext_hdr != 0)
 163                 off = 8;
 164         else
 165                 off = 4;
 166
 167         if (cmd->data_length < off) {
 168                 pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
 169                         " small for %s header\n", cmd->data_length,
 170                         (ext_hdr) ? "extended" : "normal");
 171                 return TCM_INVALID_CDB_FIELD;
 172         }
 173         buf = transport_kmap_data_sg(cmd);
 174         if (!buf)
 175                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 176
 177         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 178         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
 179                         tg_pt_gp_list) {
 180                 /*
 181                  * Check if the Target port group and Target port descriptor list
 182                  * based on tg_pt_gp_members count will fit into the response payload.
 183                  * Otherwise, bump rd_len to let the initiator know we have exceeded
 184                  * the allocation length and the response is truncated.
 185                  */
 186                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
 187                      cmd->data_length) {
 188                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
 189                         continue;
 190                 }
 191                 /*
 192                  * PREF: Preferred target port bit, determine if this
 193                  * bit should be set for port group.
 194                  */
 195                 if (tg_pt_gp->tg_pt_gp_pref)
 196                         buf[off] = 0x80;
 197                 /*
 198                  * Set the ASYMMETRIC ACCESS State
 199                  */
 200                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_access_state & 0xff;
 201                 /*
 202                  * Set supported ASYMMETRIC ACCESS State bits
 203                  */
 204                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
 205                 /*
 206                  * TARGET PORT GROUP
 207                  */
 208                 put_unaligned_be16(tg_pt_gp->tg_pt_gp_id, &buf[off]);
 209                 off += 2;
 210
 211                 off++; /* Skip over Reserved */
 212                 /*
 213                  * STATUS CODE
 214                  */
 215                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 216                 /*
 217                  * Vendor Specific field
 218                  */
 219                 buf[off++] = 0x00;
 220                 /*
 221                  * TARGET PORT COUNT
 222                  */
 223                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 224                 rd_len += 8;
 225
 226                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 227                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 228                                 lun_tg_pt_gp_link) {
 229                         /*
 230                          * Start Target Port descriptor format
 231                          *
 232                          * See spc4r17 section 6.2.7 Table 247
 233                          */
 234                         off += 2; /* Skip over Obsolete */
 235                         /*
 236                          * Set RELATIVE TARGET PORT IDENTIFIER
 237                          */
 238                         put_unaligned_be16(lun->lun_rtpi, &buf[off]);
 239                         off += 2;
 240                         rd_len += 4;
 241                 }
 242                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 243         }
 244         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 245         /*
 246          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 247          */
 248         put_unaligned_be32(rd_len, &buf[0]);
 249
 250         /*
 251          * Fill in the Extended header parameter data format if requested
 252          */
 253         if (ext_hdr != 0) {
 254                 buf[4] = 0x10;
 255                 /*
 256                  * Set the implicit transition time (in seconds) for the application
 257                  * client to use as a base for it's transition timeout value.
 258                  *
 259                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
 260                  * this CDB was received upon to determine this value individually
 261                  * for ALUA target port group.
 262                  */
 263                 spin_lock(&cmd->se_lun->lun_tg_pt_gp_lock);
 264                 tg_pt_gp = cmd->se_lun->lun_tg_pt_gp;
 265                 if (tg_pt_gp)
 266                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
 267                 spin_unlock(&cmd->se_lun->lun_tg_pt_gp_lock);
 268         }
 269         transport_kunmap_data_sg(cmd);
 270
 271         target_complete_cmd_with_length(cmd, GOOD, rd_len + 4);
 272         return 0;
 273 }
 274
 275 /*
 276  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
 277  *
 278  * See spc4r17 section 6.35
 279  */
 280 sense_reason_t
 281 target_emulate_set_target_port_groups(struct se_cmd *cmd)
 282 {
 283         struct se_device *dev = cmd->se_dev;
 284         struct se_lun *l_lun = cmd->se_lun;
 285         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 286         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 287         unsigned char *buf;
 288         unsigned char *ptr;
 289         sense_reason_t rc = TCM_NO_SENSE;
 290         u32 len = 4; /* Skip over RESERVED area in header */
 291         int alua_access_state, primary = 0, valid_states;
 292         u16 tg_pt_id, rtpi;
 293
 294         if (cmd->data_length < 4) {
 295                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
 296                         " small\n", cmd->data_length);
 297                 return TCM_INVALID_PARAMETER_LIST;
 298         }
 299
 300         buf = transport_kmap_data_sg(cmd);
 301         if (!buf)
 302                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 303
 304         /*
 305          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
 306          * for the local tg_pt_gp.
 307          */
 308         spin_lock(&l_lun->lun_tg_pt_gp_lock);
 309         l_tg_pt_gp = l_lun->lun_tg_pt_gp;
 310         if (!l_tg_pt_gp) {
 311                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 312                 pr_err("Unable to access l_lun->tg_pt_gp\n");
 313                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 314                 goto out;
 315         }
 316
 317         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
 318                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 319                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 320                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
 321                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
 322                 goto out;
 323         }
 324         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
 325         spin_unlock(&l_lun->lun_tg_pt_gp_lock);
 326
 327         ptr = &buf[4]; /* Skip over RESERVED area in header */
 328
 329         while (len < cmd->data_length) {
 330                 bool found = false;
 331                 alua_access_state = (ptr[0] & 0x0f);
 332                 /*
 333                  * Check the received ALUA access state, and determine if
 334                  * the state is a primary or secondary target port asymmetric
 335                  * access state.
 336                  */
 337                 rc = core_alua_check_transition(alua_access_state, valid_states,
 338                                                 &primary, 1);
 339                 if (rc) {
 340                         /*
 341                          * If the SET TARGET PORT GROUPS attempts to establish
 342                          * an invalid combination of target port asymmetric
 343                          * access states or attempts to establish an
 344                          * unsupported target port asymmetric access state,
 345                          * then the command shall be terminated with CHECK
 346                          * CONDITION status, with the sense key set to ILLEGAL
 347                          * REQUEST, and the additional sense code set to INVALID
 348                          * FIELD IN PARAMETER LIST.
 349                          */
 350                         goto out;
 351                 }
 352
 353                 /*
 354                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 355                  * specifies a primary target port asymmetric access state,
 356                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 357                  * a primary target port group for which the primary target
 358                  * port asymmetric access state shall be changed. If the
 359                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 360                  * port asymmetric access state, then the TARGET PORT GROUP OR
 361                  * TARGET PORT field specifies the relative target port
 362                  * identifier (see 3.1.120) of the target port for which the
 363                  * secondary target port asymmetric access state shall be
 364                  * changed.
 365                  */
 366                 if (primary) {
 367                         tg_pt_id = get_unaligned_be16(ptr + 2);
 368                         /*
 369                          * Locate the matching target port group ID from
 370                          * the global tg_pt_gp list
 371                          */
 372                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 373                         list_for_each_entry(tg_pt_gp,
 374                                         &dev->t10_alua.tg_pt_gps_list,
 375                                         tg_pt_gp_list) {
 376                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 377                                         continue;
 378
 379                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 380                                         continue;
 381
 382                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 383
 384                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 385
 386                                 if (!core_alua_do_port_transition(tg_pt_gp,
 387                                                 dev, l_lun, nacl,
 388                                                 alua_access_state, 1))
 389                                         found = true;
 390
 391                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
 392                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
 393                                 break;
 394                         }
 395                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
 396                 } else {
 397                         struct se_lun *lun;
 398
 399                         /*
 400                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
 401                          * the Target Port in question for the the incoming
 402                          * SET_TARGET_PORT_GROUPS op.
 403                          */
 404                         rtpi = get_unaligned_be16(ptr + 2);
 405                         /*
 406                          * Locate the matching relative target port identifier
 407                          * for the struct se_device storage object.
 408                          */
 409                         spin_lock(&dev->se_port_lock);
 410                         list_for_each_entry(lun, &dev->dev_sep_list,
 411                                                         lun_dev_link) {
 412                                 if (lun->lun_rtpi != rtpi)
 413                                         continue;
 414
 415                                 // XXX: racy unlock
 416                                 spin_unlock(&dev->se_port_lock);
 417
 418                                 if (!core_alua_set_tg_pt_secondary_state(
 419                                                 lun, 1, 1))
 420                                         found = true;
 421
 422                                 spin_lock(&dev->se_port_lock);
 423                                 break;
 424                         }
 425                         spin_unlock(&dev->se_port_lock);
 426                 }
 427
 428                 if (!found) {
 429                         rc = TCM_INVALID_PARAMETER_LIST;
 430                         goto out;
 431                 }
 432
 433                 ptr += 4;
 434                 len += 4;
 435         }
 436
 437 out:
 438         transport_kunmap_data_sg(cmd);
 439         if (!rc)
 440                 target_complete_cmd(cmd, GOOD);
 441         return rc;
 442 }
 443
 444 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
 445 {
 446         /*
 447          * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
 448          * The ALUA additional sense code qualifier (ASCQ) is determined
 449          * by the ALUA primary or secondary access state..
 450          */
 451         pr_debug("[%s]: ALUA TG Port not available, "
 452                 "SenseKey: NOT_READY, ASC/ASCQ: "
 453                 "0x04/0x%02x\n",
 454                 cmd->se_tfo->fabric_name, alua_ascq);
 455
 456         cmd->scsi_asc = 0x04;
 457         cmd->scsi_ascq = alua_ascq;
 458 }
 459
 460 static inline void core_alua_state_nonoptimized(
 461         struct se_cmd *cmd,
 462         unsigned char *cdb,
 463         int nonop_delay_msecs)
 464 {
 465         /*
 466          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 467          * later to determine if processing of this cmd needs to be
 468          * temporarily delayed for the Active/NonOptimized primary access state.
 469          */
 470         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 471         cmd->alua_nonop_delay = nonop_delay_msecs;
 472 }
 473
 474 static inline int core_alua_state_lba_dependent(
 475         struct se_cmd *cmd,
 476         struct t10_alua_tg_pt_gp *tg_pt_gp)
 477 {
 478         struct se_device *dev = cmd->se_dev;
 479         u64 segment_size, segment_mult, sectors, lba;
 480
 481         /* Only need to check for cdb actually containing LBAs */
 482         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
 483                 return 0;
 484
 485         spin_lock(&dev->t10_alua.lba_map_lock);
 486         segment_size = dev->t10_alua.lba_map_segment_size;
 487         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
 488         sectors = cmd->data_length / dev->dev_attrib.block_size;
 489
 490         lba = cmd->t_task_lba;
 491         while (lba < cmd->t_task_lba + sectors) {
 492                 struct t10_alua_lba_map *cur_map = NULL, *map;
 493                 struct t10_alua_lba_map_member *map_mem;
 494
 495                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
 496                                     lba_map_list) {
 497                         u64 start_lba, last_lba;
 498                         u64 first_lba = map->lba_map_first_lba;
 499
 500                         if (segment_mult) {
 501                                 u64 tmp = lba;
 502                                 start_lba = do_div(tmp, segment_size * segment_mult);
 503
 504                                 last_lba = first_lba + segment_size - 1;
 505                                 if (start_lba >= first_lba &&
 506                                     start_lba <= last_lba) {
 507                                         lba += segment_size;
 508                                         cur_map = map;
 509                                         break;
 510                                 }
 511                         } else {
 512                                 last_lba = map->lba_map_last_lba;
 513                                 if (lba >= first_lba && lba <= last_lba) {
 514                                         lba = last_lba + 1;
 515                                         cur_map = map;
 516                                         break;
 517                                 }
 518                         }
 519                 }
 520                 if (!cur_map) {
 521                         spin_unlock(&dev->t10_alua.lba_map_lock);
 522                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 523                         return 1;
 524                 }
 525                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
 526                                     lba_map_mem_list) {
 527                         if (map_mem->lba_map_mem_alua_pg_id !=
 528                             tg_pt_gp->tg_pt_gp_id)
 529                                 continue;
 530                         switch(map_mem->lba_map_mem_alua_state) {
 531                         case ALUA_ACCESS_STATE_STANDBY:
 532                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 533                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 534                                 return 1;
 535                         case ALUA_ACCESS_STATE_UNAVAILABLE:
 536                                 spin_unlock(&dev->t10_alua.lba_map_lock);
 537                                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 538                                 return 1;
 539                         default:
 540                                 break;
 541                         }
 542                 }
 543         }
 544         spin_unlock(&dev->t10_alua.lba_map_lock);
 545         return 0;
 546 }
 547
 548 static inline int core_alua_state_standby(
 549         struct se_cmd *cmd,
 550         unsigned char *cdb)
 551 {
 552         /*
 553          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 554          * spc4r17 section 5.9.2.4.4
 555          */
 556         switch (cdb[0]) {
 557         case INQUIRY:
 558         case LOG_SELECT:
 559         case LOG_SENSE:
 560         case MODE_SELECT:
 561         case MODE_SENSE:
 562         case REPORT_LUNS:
 563         case RECEIVE_DIAGNOSTIC:
 564         case SEND_DIAGNOSTIC:
 565         case READ_CAPACITY:
 566                 return 0;
 567         case SERVICE_ACTION_IN_16:
 568                 switch (cdb[1] & 0x1f) {
 569                 case SAI_READ_CAPACITY_16:
 570                         return 0;
 571                 default:
 572                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 573                         return 1;
 574                 }
 575         case MAINTENANCE_IN:
 576                 switch (cdb[1] & 0x1f) {
 577                 case MI_REPORT_TARGET_PGS:
 578                         return 0;
 579                 default:
 580                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 581                         return 1;
 582                 }
 583         case MAINTENANCE_OUT:
 584                 switch (cdb[1]) {
 585                 case MO_SET_TARGET_PGS:
 586                         return 0;
 587                 default:
 588                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 589                         return 1;
 590                 }
 591         case REQUEST_SENSE:
 592         case PERSISTENT_RESERVE_IN:
 593         case PERSISTENT_RESERVE_OUT:
 594         case READ_BUFFER:
 595         case WRITE_BUFFER:
 596                 return 0;
 597         default:
 598                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
 599                 return 1;
 600         }
 601
 602         return 0;
 603 }
 604
 605 static inline int core_alua_state_unavailable(
 606         struct se_cmd *cmd,
 607         unsigned char *cdb)
 608 {
 609         /*
 610          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 611          * spc4r17 section 5.9.2.4.5
 612          */
 613         switch (cdb[0]) {
 614         case INQUIRY:
 615         case REPORT_LUNS:
 616                 return 0;
 617         case MAINTENANCE_IN:
 618                 switch (cdb[1] & 0x1f) {
 619                 case MI_REPORT_TARGET_PGS:
 620                         return 0;
 621                 default:
 622                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 623                         return 1;
 624                 }
 625         case MAINTENANCE_OUT:
 626                 switch (cdb[1]) {
 627                 case MO_SET_TARGET_PGS:
 628                         return 0;
 629                 default:
 630                         set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 631                         return 1;
 632                 }
 633         case REQUEST_SENSE:
 634         case READ_BUFFER:
 635         case WRITE_BUFFER:
 636                 return 0;
 637         default:
 638                 set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
 639                 return 1;
 640         }
 641
 642         return 0;
 643 }
 644
 645 static inline int core_alua_state_transition(
 646         struct se_cmd *cmd,
 647         unsigned char *cdb)
 648 {
 649         /*
 650          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
 651          * spc4r17 section 5.9.2.5
 652          */
 653         switch (cdb[0]) {
 654         case INQUIRY:
 655         case REPORT_LUNS:
 656                 return 0;
 657         case MAINTENANCE_IN:
 658                 switch (cdb[1] & 0x1f) {
 659                 case MI_REPORT_TARGET_PGS:
 660                         return 0;
 661                 default:
 662                         set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 663                         return 1;
 664                 }
 665         case REQUEST_SENSE:
 666         case READ_BUFFER:
 667         case WRITE_BUFFER:
 668                 return 0;
 669         default:
 670                 set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
 671                 return 1;
 672         }
 673
 674         return 0;
 675 }
 676
 677 /*
 678  * return 1: Is used to signal LUN not accessible, and check condition/not ready
 679  * return 0: Used to signal success
 680  * return -1: Used to signal failure, and invalid cdb field
 681  */
 682 sense_reason_t
 683 target_alua_state_check(struct se_cmd *cmd)
 684 {
 685         struct se_device *dev = cmd->se_dev;
 686         unsigned char *cdb = cmd->t_task_cdb;
 687         struct se_lun *lun = cmd->se_lun;
 688         struct t10_alua_tg_pt_gp *tg_pt_gp;
 689         int out_alua_state, nonop_delay_msecs;
 690
 691         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
 692                 return 0;
 693         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
 694                 return 0;
 695
 696         /*
 697          * First, check for a struct se_port specific secondary ALUA target port
 698          * access state: OFFLINE
 699          */
 700         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
 701                 pr_debug("ALUA: Got secondary offline status for local"
 702                                 " target port\n");
 703                 set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
 704                 return TCM_CHECK_CONDITION_NOT_READY;
 705         }
 706
 707         if (!lun->lun_tg_pt_gp)
 708                 return 0;
 709
 710         spin_lock(&lun->lun_tg_pt_gp_lock);
 711         tg_pt_gp = lun->lun_tg_pt_gp;
 712         out_alua_state = tg_pt_gp->tg_pt_gp_alua_access_state;
 713         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 714
 715         // XXX: keeps using tg_pt_gp witout reference after unlock
 716         spin_unlock(&lun->lun_tg_pt_gp_lock);
 717         /*
 718          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
 719          * statement so the compiler knows explicitly to check this case first.
 720          * For the Optimized ALUA access state case, we want to process the
 721          * incoming fabric cmd ASAP..
 722          */
 723         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
 724                 return 0;
 725
 726         switch (out_alua_state) {
 727         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 728                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
 729                 break;
 730         case ALUA_ACCESS_STATE_STANDBY:
 731                 if (core_alua_state_standby(cmd, cdb))
 732                         return TCM_CHECK_CONDITION_NOT_READY;
 733                 break;
 734         case ALUA_ACCESS_STATE_UNAVAILABLE:
 735                 if (core_alua_state_unavailable(cmd, cdb))
 736                         return TCM_CHECK_CONDITION_NOT_READY;
 737                 break;
 738         case ALUA_ACCESS_STATE_TRANSITION:
 739                 if (core_alua_state_transition(cmd, cdb))
 740                         return TCM_CHECK_CONDITION_NOT_READY;
 741                 break;
 742         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 743                 if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
 744                         return TCM_CHECK_CONDITION_NOT_READY;
 745                 break;
 746         /*
 747          * OFFLINE is a secondary ALUA target port group access state, that is
 748          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
 749          */
 750         case ALUA_ACCESS_STATE_OFFLINE:
 751         default:
 752                 pr_err("Unknown ALUA access state: 0x%02x\n",
 753                                 out_alua_state);
 754                 return TCM_INVALID_CDB_FIELD;
 755         }
 756
 757         return 0;
 758 }
 759
 760 /*
 761  * Check implicit and explicit ALUA state change request.
 762  */
 763 static sense_reason_t
 764 core_alua_check_transition(int state, int valid, int *primary, int explicit)
 765 {
 766         /*
 767          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 768          * defined as primary target port asymmetric access states.
 769          */
 770         switch (state) {
 771         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 772                 if (!(valid & ALUA_AO_SUP))
 773                         goto not_supported;
 774                 *primary = 1;
 775                 break;
 776         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 777                 if (!(valid & ALUA_AN_SUP))
 778                         goto not_supported;
 779                 *primary = 1;
 780                 break;
 781         case ALUA_ACCESS_STATE_STANDBY:
 782                 if (!(valid & ALUA_S_SUP))
 783                         goto not_supported;
 784                 *primary = 1;
 785                 break;
 786         case ALUA_ACCESS_STATE_UNAVAILABLE:
 787                 if (!(valid & ALUA_U_SUP))
 788                         goto not_supported;
 789                 *primary = 1;
 790                 break;
 791         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 792                 if (!(valid & ALUA_LBD_SUP))
 793                         goto not_supported;
 794                 *primary = 1;
 795                 break;
 796         case ALUA_ACCESS_STATE_OFFLINE:
 797                 /*
 798                  * OFFLINE state is defined as a secondary target port
 799                  * asymmetric access state.
 800                  */
 801                 if (!(valid & ALUA_O_SUP))
 802                         goto not_supported;
 803                 *primary = 0;
 804                 break;
 805         case ALUA_ACCESS_STATE_TRANSITION:
 806                 if (!(valid & ALUA_T_SUP) || explicit)
 807                         /*
 808                          * Transitioning is set internally and by tcmu daemon,
 809                          * and cannot be selected through a STPG.
 810                          */
 811                         goto not_supported;
 812                 *primary = 0;
 813                 break;
 814         default:
 815                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 816                 return TCM_INVALID_PARAMETER_LIST;
 817         }
 818
 819         return 0;
 820
 821 not_supported:
 822         pr_err("ALUA access state %s not supported",
 823                core_alua_dump_state(state));
 824         return TCM_INVALID_PARAMETER_LIST;
 825 }
 826
 827 static char *core_alua_dump_state(int state)
 828 {
 829         switch (state) {
 830         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
 831                 return "Active/Optimized";
 832         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 833                 return "Active/NonOptimized";
 834         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
 835                 return "LBA Dependent";
 836         case ALUA_ACCESS_STATE_STANDBY:
 837                 return "Standby";
 838         case ALUA_ACCESS_STATE_UNAVAILABLE:
 839                 return "Unavailable";
 840         case ALUA_ACCESS_STATE_OFFLINE:
 841                 return "Offline";
 842         case ALUA_ACCESS_STATE_TRANSITION:
 843                 return "Transitioning";
 844         default:
 845                 return "Unknown";
 846         }
 847
 848         return NULL;
 849 }
 850
 851 char *core_alua_dump_status(int status)
 852 {
 853         switch (status) {
 854         case ALUA_STATUS_NONE:
 855                 return "None";
 856         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
 857                 return "Altered by Explicit STPG";
 858         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
 859                 return "Altered by Implicit ALUA";
 860         default:
 861                 return "Unknown";
 862         }
 863
 864         return NULL;
 865 }
 866
 867 /*
 868  * Used by fabric modules to determine when we need to delay processing
 869  * for the Active/NonOptimized paths..
 870  */
 871 int core_alua_check_nonop_delay(
 872         struct se_cmd *cmd)
 873 {
 874         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 875                 return 0;
 876         if (in_interrupt())
 877                 return 0;
 878         /*
 879          * The ALUA Active/NonOptimized access state delay can be disabled
 880          * in via configfs with a value of zero
 881          */
 882         if (!cmd->alua_nonop_delay)
 883                 return 0;
 884         /*
 885          * struct se_cmd->alua_nonop_delay gets set by a target port group
 886          * defined interval in core_alua_state_nonoptimized()
 887          */
 888         msleep_interruptible(cmd->alua_nonop_delay);
 889         return 0;
 890 }
 891 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 892
 893 static int core_alua_write_tpg_metadata(
 894         const char *path,
 895         unsigned char *md_buf,
 896         u32 md_buf_len)
 897 {
 898         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
 899         loff_t pos = 0;
 900         int ret;
 901
 902         if (IS_ERR(file)) {
 903                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
 904                 return -ENODEV;
 905         }
 906         ret = kernel_write(file, md_buf, md_buf_len, &pos);
 907         if (ret < 0)
 908                 pr_err("Error writing ALUA metadata file: %s\n", path);
 909         fput(file);
 910         return (ret < 0) ? -EIO : 0;
 911 }
 912
 913 static int core_alua_update_tpg_primary_metadata(
 914         struct t10_alua_tg_pt_gp *tg_pt_gp)
 915 {
 916         unsigned char *md_buf;
 917         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
 918         char *path;
 919         int len, rc;
 920
 921         lockdep_assert_held(&tg_pt_gp->tg_pt_gp_transition_mutex);
 922
 923         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
 924         if (!md_buf) {
 925                 pr_err("Unable to allocate buf for ALUA metadata\n");
 926                 return -ENOMEM;
 927         }
 928
 929         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
 930                         "tg_pt_gp_id=%hu\n"
 931                         "alua_access_state=0x%02x\n"
 932                         "alua_access_status=0x%02x\n",
 933                         tg_pt_gp->tg_pt_gp_id,
 934                         tg_pt_gp->tg_pt_gp_alua_access_state,
 935                         tg_pt_gp->tg_pt_gp_alua_access_status);
 936
 937         rc = -ENOMEM;
 938         path = kasprintf(GFP_KERNEL, "%s/alua/tpgs_%s/%s", db_root,
 939                         &wwn->unit_serial[0],
 940                         config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 941         if (path) {
 942                 rc = core_alua_write_tpg_metadata(path, md_buf, len);
 943                 kfree(path);
 944         }
 945         kfree(md_buf);
 946         return rc;
 947 }
 948
 949 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
 950 {
 951         struct se_dev_entry *se_deve;
 952         struct se_lun *lun;
 953         struct se_lun_acl *lacl;
 954
 955         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 956         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 957                                 lun_tg_pt_gp_link) {
 958                 /*
 959                  * After an implicit target port asymmetric access state
 960                  * change, a device server shall establish a unit attention
 961                  * condition for the initiator port associated with every I_T
 962                  * nexus with the additional sense code set to ASYMMETRIC
 963                  * ACCESS STATE CHANGED.
 964                  *
 965                  * After an explicit target port asymmetric access state
 966                  * change, a device server shall establish a unit attention
 967                  * condition with the additional sense code set to ASYMMETRIC
 968                  * ACCESS STATE CHANGED for the initiator port associated with
 969                  * every I_T nexus other than the I_T nexus on which the SET
 970                  * TARGET PORT GROUPS command
 971                  */
 972                 if (!percpu_ref_tryget_live(&lun->lun_ref))
 973                         continue;
 974                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 975
 976                 spin_lock(&lun->lun_deve_lock);
 977                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
 978                         lacl = rcu_dereference_check(se_deve->se_lun_acl,
 979                                         lockdep_is_held(&lun->lun_deve_lock));
 980
 981                         /*
 982                          * spc4r37 p.242:
 983                          * After an explicit target port asymmetric access
 984                          * state change, a device server shall establish a
 985                          * unit attention condition with the additional sense
 986                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
 987                          * the initiator port associated with every I_T nexus
 988                          * other than the I_T nexus on which the SET TARGET
 989                          * PORT GROUPS command was received.
 990                          */
 991                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
 992                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
 993                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
 994                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
 995                                 continue;
 996
 997                         /*
 998                          * se_deve->se_lun_acl pointer may be NULL for a
 999                          * entry created without explicit Node+MappedLUN ACLs
1000                          */
1001                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1002                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
1003                                 continue;
1004
1005                         core_scsi3_ua_allocate(se_deve, 0x2A,
1006                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1007                 }
1008                 spin_unlock(&lun->lun_deve_lock);
1009
1010                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1011                 percpu_ref_put(&lun->lun_ref);
1012         }
1013         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1014 }
1015
1016 static int core_alua_do_transition_tg_pt(
1017         struct t10_alua_tg_pt_gp *tg_pt_gp,
1018         int new_state,
1019         int explicit)
1020 {
1021         int prev_state;
1022
1023         mutex_lock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1024         /* Nothing to be done here */
1025         if (tg_pt_gp->tg_pt_gp_alua_access_state == new_state) {
1026                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1027                 return 0;
1028         }
1029
1030         if (explicit && new_state == ALUA_ACCESS_STATE_TRANSITION) {
1031                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1032                 return -EAGAIN;
1033         }
1034
1035         /*
1036          * Save the old primary ALUA access state, and set the current state
1037          * to ALUA_ACCESS_STATE_TRANSITION.
1038          */
1039         prev_state = tg_pt_gp->tg_pt_gp_alua_access_state;
1040         tg_pt_gp->tg_pt_gp_alua_access_state = ALUA_ACCESS_STATE_TRANSITION;
1041         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1042                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1043                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1044
1045         core_alua_queue_state_change_ua(tg_pt_gp);
1046
1047         if (new_state == ALUA_ACCESS_STATE_TRANSITION) {
1048                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1049                 return 0;
1050         }
1051
1052         /*
1053          * Check for the optional ALUA primary state transition delay
1054          */
1055         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1056                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1057
1058         /*
1059          * Set the current primary ALUA access state to the requested new state
1060          */
1061         tg_pt_gp->tg_pt_gp_alua_access_state = new_state;
1062
1063         /*
1064          * Update the ALUA metadata buf that has been allocated in
1065          * core_alua_do_port_transition(), this metadata will be written
1066          * to struct file.
1067          *
1068          * Note that there is the case where we do not want to update the
1069          * metadata when the saved metadata is being parsed in userspace
1070          * when setting the existing port access state and access status.
1071          *
1072          * Also note that the failure to write out the ALUA metadata to
1073          * struct file does NOT affect the actual ALUA transition.
1074          */
1075         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1076                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1077         }
1078
1079         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1080                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1081                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1082                 tg_pt_gp->tg_pt_gp_id,
1083                 core_alua_dump_state(prev_state),
1084                 core_alua_dump_state(new_state));
1085
1086         core_alua_queue_state_change_ua(tg_pt_gp);
1087
1088         mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1089         return 0;
1090 }
1091
1092 int core_alua_do_port_transition(
1093         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1094         struct se_device *l_dev,
1095         struct se_lun *l_lun,
1096         struct se_node_acl *l_nacl,
1097         int new_state,
1098         int explicit)
1099 {
1100         struct se_device *dev;
1101         struct t10_alua_lu_gp *lu_gp;
1102         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1103         struct t10_alua_tg_pt_gp *tg_pt_gp;
1104         int primary, valid_states, rc = 0;
1105
1106         if (l_dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
1107                 return -ENODEV;
1108
1109         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1110         if (core_alua_check_transition(new_state, valid_states, &primary,
1111                                        explicit) != 0)
1112                 return -EINVAL;
1113
1114         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1115         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1116         lu_gp = local_lu_gp_mem->lu_gp;
1117         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1118         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1119         /*
1120          * For storage objects that are members of the 'default_lu_gp',
1121          * we only do transition on the passed *l_tp_pt_gp, and not
1122          * on all of the matching target port groups IDs in default_lu_gp.
1123          */
1124         if (!lu_gp->lu_gp_id) {
1125                 /*
1126                  * core_alua_do_transition_tg_pt() will always return
1127                  * success.
1128                  */
1129                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1130                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1131                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1132                                                    new_state, explicit);
1133                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1134                 return rc;
1135         }
1136         /*
1137          * For all other LU groups aside from 'default_lu_gp', walk all of
1138          * the associated storage objects looking for a matching target port
1139          * group ID from the local target port group.
1140          */
1141         spin_lock(&lu_gp->lu_gp_lock);
1142         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1143                                 lu_gp_mem_list) {
1144
1145                 dev = lu_gp_mem->lu_gp_mem_dev;
1146                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1147                 spin_unlock(&lu_gp->lu_gp_lock);
1148
1149                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1150                 list_for_each_entry(tg_pt_gp,
1151                                 &dev->t10_alua.tg_pt_gps_list,
1152                                 tg_pt_gp_list) {
1153
1154                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1155                                 continue;
1156                         /*
1157                          * If the target behavior port asymmetric access state
1158                          * is changed for any target port group accessible via
1159                          * a logical unit within a LU group, the target port
1160                          * behavior group asymmetric access states for the same
1161                          * target port group accessible via other logical units
1162                          * in that LU group will also change.
1163                          */
1164                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1165                                 continue;
1166
1167                         if (l_tg_pt_gp == tg_pt_gp) {
1168                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1169                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1170                         } else {
1171                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1172                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1173                         }
1174                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1175                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1176                         /*
1177                          * core_alua_do_transition_tg_pt() will always return
1178                          * success.
1179                          */
1180                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1181                                         new_state, explicit);
1182
1183                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1184                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1185                         if (rc)
1186                                 break;
1187                 }
1188                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1189
1190                 spin_lock(&lu_gp->lu_gp_lock);
1191                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1192         }
1193         spin_unlock(&lu_gp->lu_gp_lock);
1194
1195         if (!rc) {
1196                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1197                          " Group IDs: %hu %s transition to primary state: %s\n",
1198                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1199                          l_tg_pt_gp->tg_pt_gp_id,
1200                          (explicit) ? "explicit" : "implicit",
1201                          core_alua_dump_state(new_state));
1202         }
1203
1204         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1205         return rc;
1206 }
1207
1208 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1209 {
1210         struct se_portal_group *se_tpg = lun->lun_tpg;
1211         unsigned char *md_buf;
1212         char *path;
1213         int len, rc;
1214
1215         mutex_lock(&lun->lun_tg_pt_md_mutex);
1216
1217         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1218         if (!md_buf) {
1219                 pr_err("Unable to allocate buf for ALUA metadata\n");
1220                 rc = -ENOMEM;
1221                 goto out_unlock;
1222         }
1223
1224         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1225                         "alua_tg_pt_status=0x%02x\n",
1226                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1227                         lun->lun_tg_pt_secondary_stat);
1228
1229         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) {
1230                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s+%hu/lun_%llu",
1231                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1232                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1233                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
1234                                 lun->unpacked_lun);
1235         } else {
1236                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s/lun_%llu",
1237                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1238                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1239                                 lun->unpacked_lun);
1240         }
1241         if (!path) {
1242                 rc = -ENOMEM;
1243                 goto out_free;
1244         }
1245
1246         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1247         kfree(path);
1248 out_free:
1249         kfree(md_buf);
1250 out_unlock:
1251         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1252         return rc;
1253 }
1254
1255 static int core_alua_set_tg_pt_secondary_state(
1256         struct se_lun *lun,
1257         int explicit,
1258         int offline)
1259 {
1260         struct t10_alua_tg_pt_gp *tg_pt_gp;
1261         int trans_delay_msecs;
1262
1263         spin_lock(&lun->lun_tg_pt_gp_lock);
1264         tg_pt_gp = lun->lun_tg_pt_gp;
1265         if (!tg_pt_gp) {
1266                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1267                 pr_err("Unable to complete secondary state"
1268                                 " transition\n");
1269                 return -EINVAL;
1270         }
1271         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1272         /*
1273          * Set the secondary ALUA target port access state to OFFLINE
1274          * or release the previously secondary state for struct se_lun
1275          */
1276         if (offline)
1277                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1278         else
1279                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1280
1281         lun->lun_tg_pt_secondary_stat = (explicit) ?
1282                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1283                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1284
1285         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1286                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1287                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1288                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1289
1290         spin_unlock(&lun->lun_tg_pt_gp_lock);
1291         /*
1292          * Do the optional transition delay after we set the secondary
1293          * ALUA access state.
1294          */
1295         if (trans_delay_msecs != 0)
1296                 msleep_interruptible(trans_delay_msecs);
1297         /*
1298          * See if we need to update the ALUA fabric port metadata for
1299          * secondary state and status
1300          */
1301         if (lun->lun_tg_pt_secondary_write_md)
1302                 core_alua_update_tpg_secondary_metadata(lun);
1303
1304         return 0;
1305 }
1306
1307 struct t10_alua_lba_map *
1308 core_alua_allocate_lba_map(struct list_head *list,
1309                            u64 first_lba, u64 last_lba)
1310 {
1311         struct t10_alua_lba_map *lba_map;
1312
1313         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1314         if (!lba_map) {
1315                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1316                 return ERR_PTR(-ENOMEM);
1317         }
1318         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1319         lba_map->lba_map_first_lba = first_lba;
1320         lba_map->lba_map_last_lba = last_lba;
1321
1322         list_add_tail(&lba_map->lba_map_list, list);
1323         return lba_map;
1324 }
1325
1326 int
1327 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1328                                int pg_id, int state)
1329 {
1330         struct t10_alua_lba_map_member *lba_map_mem;
1331
1332         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1333                             lba_map_mem_list) {
1334                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1335                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1336                         return -EINVAL;
1337                 }
1338         }
1339
1340         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1341         if (!lba_map_mem) {
1342                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1343                 return -ENOMEM;
1344         }
1345         lba_map_mem->lba_map_mem_alua_state = state;
1346         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1347
1348         list_add_tail(&lba_map_mem->lba_map_mem_list,
1349                       &lba_map->lba_map_mem_list);
1350         return 0;
1351 }
1352
1353 void
1354 core_alua_free_lba_map(struct list_head *lba_list)
1355 {
1356         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1357         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1358
1359         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1360                                  lba_map_list) {
1361                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1362                                          &lba_map->lba_map_mem_list,
1363                                          lba_map_mem_list) {
1364                         list_del(&lba_map_mem->lba_map_mem_list);
1365                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1366                                         lba_map_mem);
1367                 }
1368                 list_del(&lba_map->lba_map_list);
1369                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1370         }
1371 }
1372
1373 void
1374 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1375                       int segment_size, int segment_mult)
1376 {
1377         struct list_head old_lba_map_list;
1378         struct t10_alua_tg_pt_gp *tg_pt_gp;
1379         int activate = 0, supported;
1380
1381         INIT_LIST_HEAD(&old_lba_map_list);
1382         spin_lock(&dev->t10_alua.lba_map_lock);
1383         dev->t10_alua.lba_map_segment_size = segment_size;
1384         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1385         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1386         if (lba_map_list) {
1387                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1388                 activate = 1;
1389         }
1390         spin_unlock(&dev->t10_alua.lba_map_lock);
1391         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1392         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1393                             tg_pt_gp_list) {
1394
1395                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1396                         continue;
1397                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1398                 if (activate)
1399                         supported |= ALUA_LBD_SUP;
1400                 else
1401                         supported &= ~ALUA_LBD_SUP;
1402                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1403         }
1404         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1405         core_alua_free_lba_map(&old_lba_map_list);
1406 }
1407
1408 struct t10_alua_lu_gp *
1409 core_alua_allocate_lu_gp(const char *name, int def_group)
1410 {
1411         struct t10_alua_lu_gp *lu_gp;
1412
1413         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1414         if (!lu_gp) {
1415                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1416                 return ERR_PTR(-ENOMEM);
1417         }
1418         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1419         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1420         spin_lock_init(&lu_gp->lu_gp_lock);
1421         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1422
1423         if (def_group) {
1424                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1425                 lu_gp->lu_gp_valid_id = 1;
1426                 alua_lu_gps_count++;
1427         }
1428
1429         return lu_gp;
1430 }
1431
1432 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1433 {
1434         struct t10_alua_lu_gp *lu_gp_tmp;
1435         u16 lu_gp_id_tmp;
1436         /*
1437          * The lu_gp->lu_gp_id may only be set once..
1438          */
1439         if (lu_gp->lu_gp_valid_id) {
1440                 pr_warn("ALUA LU Group already has a valid ID,"
1441                         " ignoring request\n");
1442                 return -EINVAL;
1443         }
1444
1445         spin_lock(&lu_gps_lock);
1446         if (alua_lu_gps_count == 0x0000ffff) {
1447                 pr_err("Maximum ALUA alua_lu_gps_count:"
1448                                 " 0x0000ffff reached\n");
1449                 spin_unlock(&lu_gps_lock);
1450                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1451                 return -ENOSPC;
1452         }
1453 again:
1454         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1455                                 alua_lu_gps_counter++;
1456
1457         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1458                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1459                         if (!lu_gp_id)
1460                                 goto again;
1461
1462                         pr_warn("ALUA Logical Unit Group ID: %hu"
1463                                 " already exists, ignoring request\n",
1464                                 lu_gp_id);
1465                         spin_unlock(&lu_gps_lock);
1466                         return -EINVAL;
1467                 }
1468         }
1469
1470         lu_gp->lu_gp_id = lu_gp_id_tmp;
1471         lu_gp->lu_gp_valid_id = 1;
1472         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1473         alua_lu_gps_count++;
1474         spin_unlock(&lu_gps_lock);
1475
1476         return 0;
1477 }
1478
1479 static struct t10_alua_lu_gp_member *
1480 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1481 {
1482         struct t10_alua_lu_gp_member *lu_gp_mem;
1483
1484         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1485         if (!lu_gp_mem) {
1486                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1487                 return ERR_PTR(-ENOMEM);
1488         }
1489         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1490         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1491         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1492
1493         lu_gp_mem->lu_gp_mem_dev = dev;
1494         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1495
1496         return lu_gp_mem;
1497 }
1498
1499 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1500 {
1501         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1502         /*
1503          * Once we have reached this point, config_item_put() has
1504          * already been called from target_core_alua_drop_lu_gp().
1505          *
1506          * Here, we remove the *lu_gp from the global list so that
1507          * no associations can be made while we are releasing
1508          * struct t10_alua_lu_gp.
1509          */
1510         spin_lock(&lu_gps_lock);
1511         list_del(&lu_gp->lu_gp_node);
1512         alua_lu_gps_count--;
1513         spin_unlock(&lu_gps_lock);
1514         /*
1515          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1516          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1517          * released with core_alua_put_lu_gp_from_name()
1518          */
1519         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1520                 cpu_relax();
1521         /*
1522          * Release reference to struct t10_alua_lu_gp * from all associated
1523          * struct se_device.
1524          */
1525         spin_lock(&lu_gp->lu_gp_lock);
1526         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1527                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1528                 if (lu_gp_mem->lu_gp_assoc) {
1529                         list_del(&lu_gp_mem->lu_gp_mem_list);
1530                         lu_gp->lu_gp_members--;
1531                         lu_gp_mem->lu_gp_assoc = 0;
1532                 }
1533                 spin_unlock(&lu_gp->lu_gp_lock);
1534                 /*
1535                  *
1536                  * lu_gp_mem is associated with a single
1537                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1538                  * struct se_device is released via core_alua_free_lu_gp_mem().
1539                  *
1540                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1541                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1542                  */
1543                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1544                 if (lu_gp != default_lu_gp)
1545                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1546                                         default_lu_gp);
1547                 else
1548                         lu_gp_mem->lu_gp = NULL;
1549                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1550
1551                 spin_lock(&lu_gp->lu_gp_lock);
1552         }
1553         spin_unlock(&lu_gp->lu_gp_lock);
1554
1555         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1556 }
1557
1558 void core_alua_free_lu_gp_mem(struct se_device *dev)
1559 {
1560         struct t10_alua_lu_gp *lu_gp;
1561         struct t10_alua_lu_gp_member *lu_gp_mem;
1562
1563         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1564         if (!lu_gp_mem)
1565                 return;
1566
1567         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1568                 cpu_relax();
1569
1570         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1571         lu_gp = lu_gp_mem->lu_gp;
1572         if (lu_gp) {
1573                 spin_lock(&lu_gp->lu_gp_lock);
1574                 if (lu_gp_mem->lu_gp_assoc) {
1575                         list_del(&lu_gp_mem->lu_gp_mem_list);
1576                         lu_gp->lu_gp_members--;
1577                         lu_gp_mem->lu_gp_assoc = 0;
1578                 }
1579                 spin_unlock(&lu_gp->lu_gp_lock);
1580                 lu_gp_mem->lu_gp = NULL;
1581         }
1582         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1583
1584         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1585 }
1586
1587 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1588 {
1589         struct t10_alua_lu_gp *lu_gp;
1590         struct config_item *ci;
1591
1592         spin_lock(&lu_gps_lock);
1593         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1594                 if (!lu_gp->lu_gp_valid_id)
1595                         continue;
1596                 ci = &lu_gp->lu_gp_group.cg_item;
1597                 if (!strcmp(config_item_name(ci), name)) {
1598                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1599                         spin_unlock(&lu_gps_lock);
1600                         return lu_gp;
1601                 }
1602         }
1603         spin_unlock(&lu_gps_lock);
1604
1605         return NULL;
1606 }
1607
1608 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1609 {
1610         spin_lock(&lu_gps_lock);
1611         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1612         spin_unlock(&lu_gps_lock);
1613 }
1614
1615 /*
1616  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1617  */
1618 void __core_alua_attach_lu_gp_mem(
1619         struct t10_alua_lu_gp_member *lu_gp_mem,
1620         struct t10_alua_lu_gp *lu_gp)
1621 {
1622         spin_lock(&lu_gp->lu_gp_lock);
1623         lu_gp_mem->lu_gp = lu_gp;
1624         lu_gp_mem->lu_gp_assoc = 1;
1625         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1626         lu_gp->lu_gp_members++;
1627         spin_unlock(&lu_gp->lu_gp_lock);
1628 }
1629
1630 /*
1631  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1632  */
1633 void __core_alua_drop_lu_gp_mem(
1634         struct t10_alua_lu_gp_member *lu_gp_mem,
1635         struct t10_alua_lu_gp *lu_gp)
1636 {
1637         spin_lock(&lu_gp->lu_gp_lock);
1638         list_del(&lu_gp_mem->lu_gp_mem_list);
1639         lu_gp_mem->lu_gp = NULL;
1640         lu_gp_mem->lu_gp_assoc = 0;
1641         lu_gp->lu_gp_members--;
1642         spin_unlock(&lu_gp->lu_gp_lock);
1643 }
1644
1645 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1646                 const char *name, int def_group)
1647 {
1648         struct t10_alua_tg_pt_gp *tg_pt_gp;
1649
1650         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1651         if (!tg_pt_gp) {
1652                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1653                 return NULL;
1654         }
1655         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1656         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1657         mutex_init(&tg_pt_gp->tg_pt_gp_transition_mutex);
1658         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1659         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1660         tg_pt_gp->tg_pt_gp_dev = dev;
1661         tg_pt_gp->tg_pt_gp_alua_access_state =
1662                         ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED;
1663         /*
1664          * Enable both explicit and implicit ALUA support by default
1665          */
1666         tg_pt_gp->tg_pt_gp_alua_access_type =
1667                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1668         /*
1669          * Set the default Active/NonOptimized Delay in milliseconds
1670          */
1671         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1672         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1673         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1674
1675         /*
1676          * Enable all supported states
1677          */
1678         tg_pt_gp->tg_pt_gp_alua_supported_states =
1679             ALUA_T_SUP | ALUA_O_SUP |
1680             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1681
1682         if (def_group) {
1683                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1684                 tg_pt_gp->tg_pt_gp_id =
1685                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1686                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1687                 dev->t10_alua.alua_tg_pt_gps_count++;
1688                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1689                               &dev->t10_alua.tg_pt_gps_list);
1690                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1691         }
1692
1693         return tg_pt_gp;
1694 }
1695
1696 int core_alua_set_tg_pt_gp_id(
1697         struct t10_alua_tg_pt_gp *tg_pt_gp,
1698         u16 tg_pt_gp_id)
1699 {
1700         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1701         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1702         u16 tg_pt_gp_id_tmp;
1703
1704         /*
1705          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1706          */
1707         if (tg_pt_gp->tg_pt_gp_valid_id) {
1708                 pr_warn("ALUA TG PT Group already has a valid ID,"
1709                         " ignoring request\n");
1710                 return -EINVAL;
1711         }
1712
1713         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1714         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1715                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1716                         " 0x0000ffff reached\n");
1717                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1718                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1719                 return -ENOSPC;
1720         }
1721 again:
1722         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1723                         dev->t10_alua.alua_tg_pt_gps_counter++;
1724
1725         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1726                         tg_pt_gp_list) {
1727                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1728                         if (!tg_pt_gp_id)
1729                                 goto again;
1730
1731                         pr_err("ALUA Target Port Group ID: %hu already"
1732                                 " exists, ignoring request\n", tg_pt_gp_id);
1733                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1734                         return -EINVAL;
1735                 }
1736         }
1737
1738         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1739         tg_pt_gp->tg_pt_gp_valid_id = 1;
1740         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1741                         &dev->t10_alua.tg_pt_gps_list);
1742         dev->t10_alua.alua_tg_pt_gps_count++;
1743         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1744
1745         return 0;
1746 }
1747
1748 void core_alua_free_tg_pt_gp(
1749         struct t10_alua_tg_pt_gp *tg_pt_gp)
1750 {
1751         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1752         struct se_lun *lun, *next;
1753
1754         /*
1755          * Once we have reached this point, config_item_put() has already
1756          * been called from target_core_alua_drop_tg_pt_gp().
1757          *
1758          * Here we remove *tg_pt_gp from the global list so that
1759          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1760          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1761          */
1762         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1763         list_del(&tg_pt_gp->tg_pt_gp_list);
1764         dev->t10_alua.alua_tg_pt_gps_counter--;
1765         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1766
1767         /*
1768          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1769          * core_alua_get_tg_pt_gp_by_name() in
1770          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1771          * to be released with core_alua_put_tg_pt_gp_from_name().
1772          */
1773         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1774                 cpu_relax();
1775
1776         /*
1777          * Release reference to struct t10_alua_tg_pt_gp from all associated
1778          * struct se_port.
1779          */
1780         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1781         list_for_each_entry_safe(lun, next,
1782                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1783                 list_del_init(&lun->lun_tg_pt_gp_link);
1784                 tg_pt_gp->tg_pt_gp_members--;
1785
1786                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1787                 /*
1788                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1789                  * assume we want to re-associate a given tg_pt_gp_mem with
1790                  * default_tg_pt_gp.
1791                  */
1792                 spin_lock(&lun->lun_tg_pt_gp_lock);
1793                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1794                         __target_attach_tg_pt_gp(lun,
1795                                         dev->t10_alua.default_tg_pt_gp);
1796                 } else
1797                         lun->lun_tg_pt_gp = NULL;
1798                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1799
1800                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1801         }
1802         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1803
1804         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1805 }
1806
1807 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1808                 struct se_device *dev, const char *name)
1809 {
1810         struct t10_alua_tg_pt_gp *tg_pt_gp;
1811         struct config_item *ci;
1812
1813         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1814         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1815                         tg_pt_gp_list) {
1816                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1817                         continue;
1818                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1819                 if (!strcmp(config_item_name(ci), name)) {
1820                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1821                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1822                         return tg_pt_gp;
1823                 }
1824         }
1825         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1826
1827         return NULL;
1828 }
1829
1830 static void core_alua_put_tg_pt_gp_from_name(
1831         struct t10_alua_tg_pt_gp *tg_pt_gp)
1832 {
1833         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1834
1835         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1836         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1837         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1838 }
1839
1840 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1841                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1842 {
1843         struct se_dev_entry *se_deve;
1844
1845         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1846
1847         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1848         lun->lun_tg_pt_gp = tg_pt_gp;
1849         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1850         tg_pt_gp->tg_pt_gp_members++;
1851         spin_lock(&lun->lun_deve_lock);
1852         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1853                 core_scsi3_ua_allocate(se_deve, 0x3f,
1854                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1855         spin_unlock(&lun->lun_deve_lock);
1856         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1857 }
1858
1859 void target_attach_tg_pt_gp(struct se_lun *lun,
1860                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1861 {
1862         spin_lock(&lun->lun_tg_pt_gp_lock);
1863         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1864         spin_unlock(&lun->lun_tg_pt_gp_lock);
1865 }
1866
1867 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1868                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1869 {
1870         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1871
1872         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1873         list_del_init(&lun->lun_tg_pt_gp_link);
1874         tg_pt_gp->tg_pt_gp_members--;
1875         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1876
1877         lun->lun_tg_pt_gp = NULL;
1878 }
1879
1880 void target_detach_tg_pt_gp(struct se_lun *lun)
1881 {
1882         struct t10_alua_tg_pt_gp *tg_pt_gp;
1883
1884         spin_lock(&lun->lun_tg_pt_gp_lock);
1885         tg_pt_gp = lun->lun_tg_pt_gp;
1886         if (tg_pt_gp)
1887                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1888         spin_unlock(&lun->lun_tg_pt_gp_lock);
1889 }
1890
1891 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1892 {
1893         struct config_item *tg_pt_ci;
1894         struct t10_alua_tg_pt_gp *tg_pt_gp;
1895         ssize_t len = 0;
1896
1897         spin_lock(&lun->lun_tg_pt_gp_lock);
1898         tg_pt_gp = lun->lun_tg_pt_gp;
1899         if (tg_pt_gp) {
1900                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1901                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1902                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1903                         "Primary Access Status: %s\nTG Port Secondary Access"
1904                         " State: %s\nTG Port Secondary Access Status: %s\n",
1905                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1906                         core_alua_dump_state(
1907                                 tg_pt_gp->tg_pt_gp_alua_access_state),
1908                         core_alua_dump_status(
1909                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1910                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1911                         "Offline" : "None",
1912                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1913         }
1914         spin_unlock(&lun->lun_tg_pt_gp_lock);
1915
1916         return len;
1917 }
1918
1919 ssize_t core_alua_store_tg_pt_gp_info(
1920         struct se_lun *lun,
1921         const char *page,
1922         size_t count)
1923 {
1924         struct se_portal_group *tpg = lun->lun_tpg;
1925         /*
1926          * rcu_dereference_raw protected by se_lun->lun_group symlink
1927          * reference to se_device->dev_group.
1928          */
1929         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1930         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1931         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1932         int move = 0;
1933
1934         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1935             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1936                 return -ENODEV;
1937
1938         if (count > TG_PT_GROUP_NAME_BUF) {
1939                 pr_err("ALUA Target Port Group alias too large!\n");
1940                 return -EINVAL;
1941         }
1942         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1943         memcpy(buf, page, count);
1944         /*
1945          * Any ALUA target port group alias besides "NULL" means we will be
1946          * making a new group association.
1947          */
1948         if (strcmp(strstrip(buf), "NULL")) {
1949                 /*
1950                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1951                  * struct t10_alua_tg_pt_gp.  This reference is released with
1952                  * core_alua_put_tg_pt_gp_from_name() below.
1953                  */
1954                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1955                                         strstrip(buf));
1956                 if (!tg_pt_gp_new)
1957                         return -ENODEV;
1958         }
1959
1960         spin_lock(&lun->lun_tg_pt_gp_lock);
1961         tg_pt_gp = lun->lun_tg_pt_gp;
1962         if (tg_pt_gp) {
1963                 /*
1964                  * Clearing an existing tg_pt_gp association, and replacing
1965                  * with the default_tg_pt_gp.
1966                  */
1967                 if (!tg_pt_gp_new) {
1968                         pr_debug("Target_Core_ConfigFS: Moving"
1969                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1970                                 " alua/%s, ID: %hu back to"
1971                                 " default_tg_pt_gp\n",
1972                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1973                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1974                                 config_item_name(&lun->lun_group.cg_item),
1975                                 config_item_name(
1976                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1977                                 tg_pt_gp->tg_pt_gp_id);
1978
1979                         __target_detach_tg_pt_gp(lun, tg_pt_gp);
1980                         __target_attach_tg_pt_gp(lun,
1981                                         dev->t10_alua.default_tg_pt_gp);
1982                         spin_unlock(&lun->lun_tg_pt_gp_lock);
1983
1984                         return count;
1985                 }
1986                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1987                 move = 1;
1988         }
1989
1990         __target_attach_tg_pt_gp(lun, tg_pt_gp_new);
1991         spin_unlock(&lun->lun_tg_pt_gp_lock);
1992         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1993                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1994                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1995                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1996                 config_item_name(&lun->lun_group.cg_item),
1997                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1998                 tg_pt_gp_new->tg_pt_gp_id);
1999
2000         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2001         return count;
2002 }
2003
2004 ssize_t core_alua_show_access_type(
2005         struct t10_alua_tg_pt_gp *tg_pt_gp,
2006         char *page)
2007 {
2008         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2009             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2010                 return sprintf(page, "Implicit and Explicit\n");
2011         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2012                 return sprintf(page, "Implicit\n");
2013         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2014                 return sprintf(page, "Explicit\n");
2015         else
2016                 return sprintf(page, "None\n");
2017 }
2018
2019 ssize_t core_alua_store_access_type(
2020         struct t10_alua_tg_pt_gp *tg_pt_gp,
2021         const char *page,
2022         size_t count)
2023 {
2024         unsigned long tmp;
2025         int ret;
2026
2027         ret = kstrtoul(page, 0, &tmp);
2028         if (ret < 0) {
2029                 pr_err("Unable to extract alua_access_type\n");
2030                 return ret;
2031         }
2032         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2033                 pr_err("Illegal value for alua_access_type:"
2034                                 " %lu\n", tmp);
2035                 return -EINVAL;
2036         }
2037         if (tmp == 3)
2038                 tg_pt_gp->tg_pt_gp_alua_access_type =
2039                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2040         else if (tmp == 2)
2041                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2042         else if (tmp == 1)
2043                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2044         else
2045                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2046
2047         return count;
2048 }
2049
2050 ssize_t core_alua_show_nonop_delay_msecs(
2051         struct t10_alua_tg_pt_gp *tg_pt_gp,
2052         char *page)
2053 {
2054         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2055 }
2056
2057 ssize_t core_alua_store_nonop_delay_msecs(
2058         struct t10_alua_tg_pt_gp *tg_pt_gp,
2059         const char *page,
2060         size_t count)
2061 {
2062         unsigned long tmp;
2063         int ret;
2064
2065         ret = kstrtoul(page, 0, &tmp);
2066         if (ret < 0) {
2067                 pr_err("Unable to extract nonop_delay_msecs\n");
2068                 return ret;
2069         }
2070         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2071                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2072                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2073                         ALUA_MAX_NONOP_DELAY_MSECS);
2074                 return -EINVAL;
2075         }
2076         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2077
2078         return count;
2079 }
2080
2081 ssize_t core_alua_show_trans_delay_msecs(
2082         struct t10_alua_tg_pt_gp *tg_pt_gp,
2083         char *page)
2084 {
2085         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2086 }
2087
2088 ssize_t core_alua_store_trans_delay_msecs(
2089         struct t10_alua_tg_pt_gp *tg_pt_gp,
2090         const char *page,
2091         size_t count)
2092 {
2093         unsigned long tmp;
2094         int ret;
2095
2096         ret = kstrtoul(page, 0, &tmp);
2097         if (ret < 0) {
2098                 pr_err("Unable to extract trans_delay_msecs\n");
2099                 return ret;
2100         }
2101         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2102                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2103                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2104                         ALUA_MAX_TRANS_DELAY_MSECS);
2105                 return -EINVAL;
2106         }
2107         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2108
2109         return count;
2110 }
2111
2112 ssize_t core_alua_show_implicit_trans_secs(
2113         struct t10_alua_tg_pt_gp *tg_pt_gp,
2114         char *page)
2115 {
2116         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2117 }
2118
2119 ssize_t core_alua_store_implicit_trans_secs(
2120         struct t10_alua_tg_pt_gp *tg_pt_gp,
2121         const char *page,
2122         size_t count)
2123 {
2124         unsigned long tmp;
2125         int ret;
2126
2127         ret = kstrtoul(page, 0, &tmp);
2128         if (ret < 0) {
2129                 pr_err("Unable to extract implicit_trans_secs\n");
2130                 return ret;
2131         }
2132         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2133                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2134                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2135                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2136                 return  -EINVAL;
2137         }
2138         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2139
2140         return count;
2141 }
2142
2143 ssize_t core_alua_show_preferred_bit(
2144         struct t10_alua_tg_pt_gp *tg_pt_gp,
2145         char *page)
2146 {
2147         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2148 }
2149
2150 ssize_t core_alua_store_preferred_bit(
2151         struct t10_alua_tg_pt_gp *tg_pt_gp,
2152         const char *page,
2153         size_t count)
2154 {
2155         unsigned long tmp;
2156         int ret;
2157
2158         ret = kstrtoul(page, 0, &tmp);
2159         if (ret < 0) {
2160                 pr_err("Unable to extract preferred ALUA value\n");
2161                 return ret;
2162         }
2163         if ((tmp != 0) && (tmp != 1)) {
2164                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2165                 return -EINVAL;
2166         }
2167         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2168
2169         return count;
2170 }
2171
2172 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2173 {
2174         return sprintf(page, "%d\n",
2175                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2176 }
2177
2178 ssize_t core_alua_store_offline_bit(
2179         struct se_lun *lun,
2180         const char *page,
2181         size_t count)
2182 {
2183         /*
2184          * rcu_dereference_raw protected by se_lun->lun_group symlink
2185          * reference to se_device->dev_group.
2186          */
2187         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2188         unsigned long tmp;
2189         int ret;
2190
2191         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2192             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2193                 return -ENODEV;
2194
2195         ret = kstrtoul(page, 0, &tmp);
2196         if (ret < 0) {
2197                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2198                 return ret;
2199         }
2200         if ((tmp != 0) && (tmp != 1)) {
2201                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2202                                 tmp);
2203                 return -EINVAL;
2204         }
2205
2206         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2207         if (ret < 0)
2208                 return -EINVAL;
2209
2210         return count;
2211 }
2212
2213 ssize_t core_alua_show_secondary_status(
2214         struct se_lun *lun,
2215         char *page)
2216 {
2217         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2218 }
2219
2220 ssize_t core_alua_store_secondary_status(
2221         struct se_lun *lun,
2222         const char *page,
2223         size_t count)
2224 {
2225         unsigned long tmp;
2226         int ret;
2227
2228         ret = kstrtoul(page, 0, &tmp);
2229         if (ret < 0) {
2230                 pr_err("Unable to extract alua_tg_pt_status\n");
2231                 return ret;
2232         }
2233         if ((tmp != ALUA_STATUS_NONE) &&
2234             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2235             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2236                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2237                                 tmp);
2238                 return -EINVAL;
2239         }
2240         lun->lun_tg_pt_secondary_stat = (int)tmp;
2241
2242         return count;
2243 }
2244
2245 ssize_t core_alua_show_secondary_write_metadata(
2246         struct se_lun *lun,
2247         char *page)
2248 {
2249         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2250 }
2251
2252 ssize_t core_alua_store_secondary_write_metadata(
2253         struct se_lun *lun,
2254         const char *page,
2255         size_t count)
2256 {
2257         unsigned long tmp;
2258         int ret;
2259
2260         ret = kstrtoul(page, 0, &tmp);
2261         if (ret < 0) {
2262                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2263                 return ret;
2264         }
2265         if ((tmp != 0) && (tmp != 1)) {
2266                 pr_err("Illegal value for alua_tg_pt_write_md:"
2267                                 " %lu\n", tmp);
2268                 return -EINVAL;
2269         }
2270         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2271
2272         return count;
2273 }
2274
2275 int core_setup_alua(struct se_device *dev)
2276 {
2277         if (!(dev->transport->transport_flags &
2278              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2279             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2280                 struct t10_alua_lu_gp_member *lu_gp_mem;
2281
2282                 /*
2283                  * Associate this struct se_device with the default ALUA
2284                  * LUN Group.
2285                  */
2286                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2287                 if (IS_ERR(lu_gp_mem))
2288                         return PTR_ERR(lu_gp_mem);
2289
2290                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2291                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2292                                 default_lu_gp);
2293                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2294
2295                 pr_debug("%s: Adding to default ALUA LU Group:"
2296                         " core/alua/lu_gps/default_lu_gp\n",
2297                         dev->transport->name);
2298         }
2299
2300         return 0;
2301 }