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(cmd, GOOD);
 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->get_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 /*
 914  * Called with tg_pt_gp->tg_pt_gp_transition_mutex held
 915  */
 916 static int core_alua_update_tpg_primary_metadata(
 917         struct t10_alua_tg_pt_gp *tg_pt_gp)
 918 {
 919         unsigned char *md_buf;
 920         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
 921         char path[ALUA_METADATA_PATH_LEN];
 922         int len, rc;
 923
 924         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
 925         if (!md_buf) {
 926                 pr_err("Unable to allocate buf for ALUA metadata\n");
 927                 return -ENOMEM;
 928         }
 929
 930         memset(path, 0, ALUA_METADATA_PATH_LEN);
 931
 932         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
 933                         "tg_pt_gp_id=%hu\n"
 934                         "alua_access_state=0x%02x\n"
 935                         "alua_access_status=0x%02x\n",
 936                         tg_pt_gp->tg_pt_gp_id,
 937                         tg_pt_gp->tg_pt_gp_alua_access_state,
 938                         tg_pt_gp->tg_pt_gp_alua_access_status);
 939
 940         snprintf(path, ALUA_METADATA_PATH_LEN,
 941                 "%s/alua/tpgs_%s/%s", db_root, &wwn->unit_serial[0],
 942                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 943
 944         rc = core_alua_write_tpg_metadata(path, md_buf, len);
 945         kfree(md_buf);
 946         return rc;
 947 }
 948
 949 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
 950 {
 951         struct se_dev_entry *se_deve;
 952         struct se_lun *lun;
 953         struct se_lun_acl *lacl;
 954
 955         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 956         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
 957                                 lun_tg_pt_gp_link) {
 958                 /*
 959                  * After an implicit target port asymmetric access state
 960                  * change, a device server shall establish a unit attention
 961                  * condition for the initiator port associated with every I_T
 962                  * nexus with the additional sense code set to ASYMMETRIC
 963                  * ACCESS STATE CHANGED.
 964                  *
 965                  * After an explicit target port asymmetric access state
 966                  * change, a device server shall establish a unit attention
 967                  * condition with the additional sense code set to ASYMMETRIC
 968                  * ACCESS STATE CHANGED for the initiator port associated with
 969                  * every I_T nexus other than the I_T nexus on which the SET
 970                  * TARGET PORT GROUPS command
 971                  */
 972                 if (!percpu_ref_tryget_live(&lun->lun_ref))
 973                         continue;
 974                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 975
 976                 spin_lock(&lun->lun_deve_lock);
 977                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
 978                         lacl = rcu_dereference_check(se_deve->se_lun_acl,
 979                                         lockdep_is_held(&lun->lun_deve_lock));
 980
 981                         /*
 982                          * spc4r37 p.242:
 983                          * After an explicit target port asymmetric access
 984                          * state change, a device server shall establish a
 985                          * unit attention condition with the additional sense
 986                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
 987                          * the initiator port associated with every I_T nexus
 988                          * other than the I_T nexus on which the SET TARGET
 989                          * PORT GROUPS command was received.
 990                          */
 991                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
 992                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
 993                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
 994                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
 995                                 continue;
 996
 997                         /*
 998                          * se_deve->se_lun_acl pointer may be NULL for a
 999                          * entry created without explicit Node+MappedLUN ACLs
1000                          */
1001                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1002                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
1003                                 continue;
1004
1005                         core_scsi3_ua_allocate(se_deve, 0x2A,
1006                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1007                 }
1008                 spin_unlock(&lun->lun_deve_lock);
1009
1010                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1011                 percpu_ref_put(&lun->lun_ref);
1012         }
1013         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1014 }
1015
1016 static 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[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
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         memset(path, 0, ALUA_METADATA_PATH_LEN);
1225         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1226
1227         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1228                         se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1229
1230         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1231                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1232                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1233
1234         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1235                         "alua_tg_pt_status=0x%02x\n",
1236                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1237                         lun->lun_tg_pt_secondary_stat);
1238
1239         snprintf(path, ALUA_METADATA_PATH_LEN, "%s/alua/%s/%s/lun_%llu",
1240                         db_root, se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1241                         lun->unpacked_lun);
1242
1243         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1244         kfree(md_buf);
1245
1246 out_unlock:
1247         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1248         return rc;
1249 }
1250
1251 static int core_alua_set_tg_pt_secondary_state(
1252         struct se_lun *lun,
1253         int explicit,
1254         int offline)
1255 {
1256         struct t10_alua_tg_pt_gp *tg_pt_gp;
1257         int trans_delay_msecs;
1258
1259         spin_lock(&lun->lun_tg_pt_gp_lock);
1260         tg_pt_gp = lun->lun_tg_pt_gp;
1261         if (!tg_pt_gp) {
1262                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1263                 pr_err("Unable to complete secondary state"
1264                                 " transition\n");
1265                 return -EINVAL;
1266         }
1267         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1268         /*
1269          * Set the secondary ALUA target port access state to OFFLINE
1270          * or release the previously secondary state for struct se_lun
1271          */
1272         if (offline)
1273                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1274         else
1275                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1276
1277         lun->lun_tg_pt_secondary_stat = (explicit) ?
1278                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1279                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1280
1281         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1282                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1283                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1284                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1285
1286         spin_unlock(&lun->lun_tg_pt_gp_lock);
1287         /*
1288          * Do the optional transition delay after we set the secondary
1289          * ALUA access state.
1290          */
1291         if (trans_delay_msecs != 0)
1292                 msleep_interruptible(trans_delay_msecs);
1293         /*
1294          * See if we need to update the ALUA fabric port metadata for
1295          * secondary state and status
1296          */
1297         if (lun->lun_tg_pt_secondary_write_md)
1298                 core_alua_update_tpg_secondary_metadata(lun);
1299
1300         return 0;
1301 }
1302
1303 struct t10_alua_lba_map *
1304 core_alua_allocate_lba_map(struct list_head *list,
1305                            u64 first_lba, u64 last_lba)
1306 {
1307         struct t10_alua_lba_map *lba_map;
1308
1309         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1310         if (!lba_map) {
1311                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1312                 return ERR_PTR(-ENOMEM);
1313         }
1314         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1315         lba_map->lba_map_first_lba = first_lba;
1316         lba_map->lba_map_last_lba = last_lba;
1317
1318         list_add_tail(&lba_map->lba_map_list, list);
1319         return lba_map;
1320 }
1321
1322 int
1323 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1324                                int pg_id, int state)
1325 {
1326         struct t10_alua_lba_map_member *lba_map_mem;
1327
1328         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1329                             lba_map_mem_list) {
1330                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1331                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1332                         return -EINVAL;
1333                 }
1334         }
1335
1336         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1337         if (!lba_map_mem) {
1338                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1339                 return -ENOMEM;
1340         }
1341         lba_map_mem->lba_map_mem_alua_state = state;
1342         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1343
1344         list_add_tail(&lba_map_mem->lba_map_mem_list,
1345                       &lba_map->lba_map_mem_list);
1346         return 0;
1347 }
1348
1349 void
1350 core_alua_free_lba_map(struct list_head *lba_list)
1351 {
1352         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1353         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1354
1355         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1356                                  lba_map_list) {
1357                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1358                                          &lba_map->lba_map_mem_list,
1359                                          lba_map_mem_list) {
1360                         list_del(&lba_map_mem->lba_map_mem_list);
1361                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1362                                         lba_map_mem);
1363                 }
1364                 list_del(&lba_map->lba_map_list);
1365                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1366         }
1367 }
1368
1369 void
1370 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1371                       int segment_size, int segment_mult)
1372 {
1373         struct list_head old_lba_map_list;
1374         struct t10_alua_tg_pt_gp *tg_pt_gp;
1375         int activate = 0, supported;
1376
1377         INIT_LIST_HEAD(&old_lba_map_list);
1378         spin_lock(&dev->t10_alua.lba_map_lock);
1379         dev->t10_alua.lba_map_segment_size = segment_size;
1380         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1381         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1382         if (lba_map_list) {
1383                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1384                 activate = 1;
1385         }
1386         spin_unlock(&dev->t10_alua.lba_map_lock);
1387         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1388         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1389                             tg_pt_gp_list) {
1390
1391                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1392                         continue;
1393                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1394                 if (activate)
1395                         supported |= ALUA_LBD_SUP;
1396                 else
1397                         supported &= ~ALUA_LBD_SUP;
1398                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1399         }
1400         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1401         core_alua_free_lba_map(&old_lba_map_list);
1402 }
1403
1404 struct t10_alua_lu_gp *
1405 core_alua_allocate_lu_gp(const char *name, int def_group)
1406 {
1407         struct t10_alua_lu_gp *lu_gp;
1408
1409         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1410         if (!lu_gp) {
1411                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1412                 return ERR_PTR(-ENOMEM);
1413         }
1414         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1415         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1416         spin_lock_init(&lu_gp->lu_gp_lock);
1417         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1418
1419         if (def_group) {
1420                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1421                 lu_gp->lu_gp_valid_id = 1;
1422                 alua_lu_gps_count++;
1423         }
1424
1425         return lu_gp;
1426 }
1427
1428 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1429 {
1430         struct t10_alua_lu_gp *lu_gp_tmp;
1431         u16 lu_gp_id_tmp;
1432         /*
1433          * The lu_gp->lu_gp_id may only be set once..
1434          */
1435         if (lu_gp->lu_gp_valid_id) {
1436                 pr_warn("ALUA LU Group already has a valid ID,"
1437                         " ignoring request\n");
1438                 return -EINVAL;
1439         }
1440
1441         spin_lock(&lu_gps_lock);
1442         if (alua_lu_gps_count == 0x0000ffff) {
1443                 pr_err("Maximum ALUA alua_lu_gps_count:"
1444                                 " 0x0000ffff reached\n");
1445                 spin_unlock(&lu_gps_lock);
1446                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1447                 return -ENOSPC;
1448         }
1449 again:
1450         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1451                                 alua_lu_gps_counter++;
1452
1453         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1454                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1455                         if (!lu_gp_id)
1456                                 goto again;
1457
1458                         pr_warn("ALUA Logical Unit Group ID: %hu"
1459                                 " already exists, ignoring request\n",
1460                                 lu_gp_id);
1461                         spin_unlock(&lu_gps_lock);
1462                         return -EINVAL;
1463                 }
1464         }
1465
1466         lu_gp->lu_gp_id = lu_gp_id_tmp;
1467         lu_gp->lu_gp_valid_id = 1;
1468         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1469         alua_lu_gps_count++;
1470         spin_unlock(&lu_gps_lock);
1471
1472         return 0;
1473 }
1474
1475 static struct t10_alua_lu_gp_member *
1476 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1477 {
1478         struct t10_alua_lu_gp_member *lu_gp_mem;
1479
1480         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1481         if (!lu_gp_mem) {
1482                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1483                 return ERR_PTR(-ENOMEM);
1484         }
1485         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1486         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1487         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1488
1489         lu_gp_mem->lu_gp_mem_dev = dev;
1490         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1491
1492         return lu_gp_mem;
1493 }
1494
1495 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1496 {
1497         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1498         /*
1499          * Once we have reached this point, config_item_put() has
1500          * already been called from target_core_alua_drop_lu_gp().
1501          *
1502          * Here, we remove the *lu_gp from the global list so that
1503          * no associations can be made while we are releasing
1504          * struct t10_alua_lu_gp.
1505          */
1506         spin_lock(&lu_gps_lock);
1507         list_del(&lu_gp->lu_gp_node);
1508         alua_lu_gps_count--;
1509         spin_unlock(&lu_gps_lock);
1510         /*
1511          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1512          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1513          * released with core_alua_put_lu_gp_from_name()
1514          */
1515         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1516                 cpu_relax();
1517         /*
1518          * Release reference to struct t10_alua_lu_gp * from all associated
1519          * struct se_device.
1520          */
1521         spin_lock(&lu_gp->lu_gp_lock);
1522         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1523                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1524                 if (lu_gp_mem->lu_gp_assoc) {
1525                         list_del(&lu_gp_mem->lu_gp_mem_list);
1526                         lu_gp->lu_gp_members--;
1527                         lu_gp_mem->lu_gp_assoc = 0;
1528                 }
1529                 spin_unlock(&lu_gp->lu_gp_lock);
1530                 /*
1531                  *
1532                  * lu_gp_mem is associated with a single
1533                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1534                  * struct se_device is released via core_alua_free_lu_gp_mem().
1535                  *
1536                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1537                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1538                  */
1539                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1540                 if (lu_gp != default_lu_gp)
1541                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1542                                         default_lu_gp);
1543                 else
1544                         lu_gp_mem->lu_gp = NULL;
1545                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1546
1547                 spin_lock(&lu_gp->lu_gp_lock);
1548         }
1549         spin_unlock(&lu_gp->lu_gp_lock);
1550
1551         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1552 }
1553
1554 void core_alua_free_lu_gp_mem(struct se_device *dev)
1555 {
1556         struct t10_alua_lu_gp *lu_gp;
1557         struct t10_alua_lu_gp_member *lu_gp_mem;
1558
1559         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1560         if (!lu_gp_mem)
1561                 return;
1562
1563         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1564                 cpu_relax();
1565
1566         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1567         lu_gp = lu_gp_mem->lu_gp;
1568         if (lu_gp) {
1569                 spin_lock(&lu_gp->lu_gp_lock);
1570                 if (lu_gp_mem->lu_gp_assoc) {
1571                         list_del(&lu_gp_mem->lu_gp_mem_list);
1572                         lu_gp->lu_gp_members--;
1573                         lu_gp_mem->lu_gp_assoc = 0;
1574                 }
1575                 spin_unlock(&lu_gp->lu_gp_lock);
1576                 lu_gp_mem->lu_gp = NULL;
1577         }
1578         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1579
1580         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1581 }
1582
1583 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1584 {
1585         struct t10_alua_lu_gp *lu_gp;
1586         struct config_item *ci;
1587
1588         spin_lock(&lu_gps_lock);
1589         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1590                 if (!lu_gp->lu_gp_valid_id)
1591                         continue;
1592                 ci = &lu_gp->lu_gp_group.cg_item;
1593                 if (!strcmp(config_item_name(ci), name)) {
1594                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1595                         spin_unlock(&lu_gps_lock);
1596                         return lu_gp;
1597                 }
1598         }
1599         spin_unlock(&lu_gps_lock);
1600
1601         return NULL;
1602 }
1603
1604 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1605 {
1606         spin_lock(&lu_gps_lock);
1607         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1608         spin_unlock(&lu_gps_lock);
1609 }
1610
1611 /*
1612  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1613  */
1614 void __core_alua_attach_lu_gp_mem(
1615         struct t10_alua_lu_gp_member *lu_gp_mem,
1616         struct t10_alua_lu_gp *lu_gp)
1617 {
1618         spin_lock(&lu_gp->lu_gp_lock);
1619         lu_gp_mem->lu_gp = lu_gp;
1620         lu_gp_mem->lu_gp_assoc = 1;
1621         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1622         lu_gp->lu_gp_members++;
1623         spin_unlock(&lu_gp->lu_gp_lock);
1624 }
1625
1626 /*
1627  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1628  */
1629 void __core_alua_drop_lu_gp_mem(
1630         struct t10_alua_lu_gp_member *lu_gp_mem,
1631         struct t10_alua_lu_gp *lu_gp)
1632 {
1633         spin_lock(&lu_gp->lu_gp_lock);
1634         list_del(&lu_gp_mem->lu_gp_mem_list);
1635         lu_gp_mem->lu_gp = NULL;
1636         lu_gp_mem->lu_gp_assoc = 0;
1637         lu_gp->lu_gp_members--;
1638         spin_unlock(&lu_gp->lu_gp_lock);
1639 }
1640
1641 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1642                 const char *name, int def_group)
1643 {
1644         struct t10_alua_tg_pt_gp *tg_pt_gp;
1645
1646         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1647         if (!tg_pt_gp) {
1648                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1649                 return NULL;
1650         }
1651         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1652         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1653         mutex_init(&tg_pt_gp->tg_pt_gp_transition_mutex);
1654         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1655         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1656         tg_pt_gp->tg_pt_gp_dev = dev;
1657         tg_pt_gp->tg_pt_gp_alua_access_state =
1658                         ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED;
1659         /*
1660          * Enable both explicit and implicit ALUA support by default
1661          */
1662         tg_pt_gp->tg_pt_gp_alua_access_type =
1663                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1664         /*
1665          * Set the default Active/NonOptimized Delay in milliseconds
1666          */
1667         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1668         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1669         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1670
1671         /*
1672          * Enable all supported states
1673          */
1674         tg_pt_gp->tg_pt_gp_alua_supported_states =
1675             ALUA_T_SUP | ALUA_O_SUP |
1676             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1677
1678         if (def_group) {
1679                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1680                 tg_pt_gp->tg_pt_gp_id =
1681                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1682                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1683                 dev->t10_alua.alua_tg_pt_gps_count++;
1684                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1685                               &dev->t10_alua.tg_pt_gps_list);
1686                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1687         }
1688
1689         return tg_pt_gp;
1690 }
1691
1692 int core_alua_set_tg_pt_gp_id(
1693         struct t10_alua_tg_pt_gp *tg_pt_gp,
1694         u16 tg_pt_gp_id)
1695 {
1696         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1697         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1698         u16 tg_pt_gp_id_tmp;
1699
1700         /*
1701          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1702          */
1703         if (tg_pt_gp->tg_pt_gp_valid_id) {
1704                 pr_warn("ALUA TG PT Group already has a valid ID,"
1705                         " ignoring request\n");
1706                 return -EINVAL;
1707         }
1708
1709         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1710         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1711                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1712                         " 0x0000ffff reached\n");
1713                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1714                 return -ENOSPC;
1715         }
1716 again:
1717         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1718                         dev->t10_alua.alua_tg_pt_gps_counter++;
1719
1720         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1721                         tg_pt_gp_list) {
1722                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1723                         if (!tg_pt_gp_id)
1724                                 goto again;
1725
1726                         pr_err("ALUA Target Port Group ID: %hu already"
1727                                 " exists, ignoring request\n", tg_pt_gp_id);
1728                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1729                         return -EINVAL;
1730                 }
1731         }
1732
1733         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1734         tg_pt_gp->tg_pt_gp_valid_id = 1;
1735         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1736                         &dev->t10_alua.tg_pt_gps_list);
1737         dev->t10_alua.alua_tg_pt_gps_count++;
1738         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1739
1740         return 0;
1741 }
1742
1743 void core_alua_free_tg_pt_gp(
1744         struct t10_alua_tg_pt_gp *tg_pt_gp)
1745 {
1746         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1747         struct se_lun *lun, *next;
1748
1749         /*
1750          * Once we have reached this point, config_item_put() has already
1751          * been called from target_core_alua_drop_tg_pt_gp().
1752          *
1753          * Here we remove *tg_pt_gp from the global list so that
1754          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1755          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1756          */
1757         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1758         list_del(&tg_pt_gp->tg_pt_gp_list);
1759         dev->t10_alua.alua_tg_pt_gps_counter--;
1760         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1761
1762         /*
1763          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1764          * core_alua_get_tg_pt_gp_by_name() in
1765          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1766          * to be released with core_alua_put_tg_pt_gp_from_name().
1767          */
1768         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1769                 cpu_relax();
1770
1771         /*
1772          * Release reference to struct t10_alua_tg_pt_gp from all associated
1773          * struct se_port.
1774          */
1775         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1776         list_for_each_entry_safe(lun, next,
1777                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1778                 list_del_init(&lun->lun_tg_pt_gp_link);
1779                 tg_pt_gp->tg_pt_gp_members--;
1780
1781                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1782                 /*
1783                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1784                  * assume we want to re-associate a given tg_pt_gp_mem with
1785                  * default_tg_pt_gp.
1786                  */
1787                 spin_lock(&lun->lun_tg_pt_gp_lock);
1788                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1789                         __target_attach_tg_pt_gp(lun,
1790                                         dev->t10_alua.default_tg_pt_gp);
1791                 } else
1792                         lun->lun_tg_pt_gp = NULL;
1793                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1794
1795                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1796         }
1797         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1798
1799         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1800 }
1801
1802 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1803                 struct se_device *dev, const char *name)
1804 {
1805         struct t10_alua_tg_pt_gp *tg_pt_gp;
1806         struct config_item *ci;
1807
1808         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1809         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1810                         tg_pt_gp_list) {
1811                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1812                         continue;
1813                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1814                 if (!strcmp(config_item_name(ci), name)) {
1815                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1816                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1817                         return tg_pt_gp;
1818                 }
1819         }
1820         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1821
1822         return NULL;
1823 }
1824
1825 static void core_alua_put_tg_pt_gp_from_name(
1826         struct t10_alua_tg_pt_gp *tg_pt_gp)
1827 {
1828         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1829
1830         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1831         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1832         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1833 }
1834
1835 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1836                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1837 {
1838         struct se_dev_entry *se_deve;
1839
1840         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1841
1842         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1843         lun->lun_tg_pt_gp = tg_pt_gp;
1844         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1845         tg_pt_gp->tg_pt_gp_members++;
1846         spin_lock(&lun->lun_deve_lock);
1847         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1848                 core_scsi3_ua_allocate(se_deve, 0x3f,
1849                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1850         spin_unlock(&lun->lun_deve_lock);
1851         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1852 }
1853
1854 void target_attach_tg_pt_gp(struct se_lun *lun,
1855                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1856 {
1857         spin_lock(&lun->lun_tg_pt_gp_lock);
1858         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1859         spin_unlock(&lun->lun_tg_pt_gp_lock);
1860 }
1861
1862 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1863                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1864 {
1865         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1866
1867         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1868         list_del_init(&lun->lun_tg_pt_gp_link);
1869         tg_pt_gp->tg_pt_gp_members--;
1870         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1871
1872         lun->lun_tg_pt_gp = NULL;
1873 }
1874
1875 void target_detach_tg_pt_gp(struct se_lun *lun)
1876 {
1877         struct t10_alua_tg_pt_gp *tg_pt_gp;
1878
1879         spin_lock(&lun->lun_tg_pt_gp_lock);
1880         tg_pt_gp = lun->lun_tg_pt_gp;
1881         if (tg_pt_gp)
1882                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1883         spin_unlock(&lun->lun_tg_pt_gp_lock);
1884 }
1885
1886 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1887 {
1888         struct config_item *tg_pt_ci;
1889         struct t10_alua_tg_pt_gp *tg_pt_gp;
1890         ssize_t len = 0;
1891
1892         spin_lock(&lun->lun_tg_pt_gp_lock);
1893         tg_pt_gp = lun->lun_tg_pt_gp;
1894         if (tg_pt_gp) {
1895                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1896                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1897                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1898                         "Primary Access Status: %s\nTG Port Secondary Access"
1899                         " State: %s\nTG Port Secondary Access Status: %s\n",
1900                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1901                         core_alua_dump_state(
1902                                 tg_pt_gp->tg_pt_gp_alua_access_state),
1903                         core_alua_dump_status(
1904                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1905                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1906                         "Offline" : "None",
1907                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1908         }
1909         spin_unlock(&lun->lun_tg_pt_gp_lock);
1910
1911         return len;
1912 }
1913
1914 ssize_t core_alua_store_tg_pt_gp_info(
1915         struct se_lun *lun,
1916         const char *page,
1917         size_t count)
1918 {
1919         struct se_portal_group *tpg = lun->lun_tpg;
1920         /*
1921          * rcu_dereference_raw protected by se_lun->lun_group symlink
1922          * reference to se_device->dev_group.
1923          */
1924         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1925         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1926         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1927         int move = 0;
1928
1929         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1930             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1931                 return -ENODEV;
1932
1933         if (count > TG_PT_GROUP_NAME_BUF) {
1934                 pr_err("ALUA Target Port Group alias too large!\n");
1935                 return -EINVAL;
1936         }
1937         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1938         memcpy(buf, page, count);
1939         /*
1940          * Any ALUA target port group alias besides "NULL" means we will be
1941          * making a new group association.
1942          */
1943         if (strcmp(strstrip(buf), "NULL")) {
1944                 /*
1945                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1946                  * struct t10_alua_tg_pt_gp.  This reference is released with
1947                  * core_alua_put_tg_pt_gp_from_name() below.
1948                  */
1949                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1950                                         strstrip(buf));
1951                 if (!tg_pt_gp_new)
1952                         return -ENODEV;
1953         }
1954
1955         spin_lock(&lun->lun_tg_pt_gp_lock);
1956         tg_pt_gp = lun->lun_tg_pt_gp;
1957         if (tg_pt_gp) {
1958                 /*
1959                  * Clearing an existing tg_pt_gp association, and replacing
1960                  * with the default_tg_pt_gp.
1961                  */
1962                 if (!tg_pt_gp_new) {
1963                         pr_debug("Target_Core_ConfigFS: Moving"
1964                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1965                                 " alua/%s, ID: %hu back to"
1966                                 " default_tg_pt_gp\n",
1967                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1968                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1969                                 config_item_name(&lun->lun_group.cg_item),
1970                                 config_item_name(
1971                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1972                                 tg_pt_gp->tg_pt_gp_id);
1973
1974                         __target_detach_tg_pt_gp(lun, tg_pt_gp);
1975                         __target_attach_tg_pt_gp(lun,
1976                                         dev->t10_alua.default_tg_pt_gp);
1977                         spin_unlock(&lun->lun_tg_pt_gp_lock);
1978
1979                         return count;
1980                 }
1981                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1982                 move = 1;
1983         }
1984
1985         __target_attach_tg_pt_gp(lun, tg_pt_gp_new);
1986         spin_unlock(&lun->lun_tg_pt_gp_lock);
1987         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1988                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1989                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1990                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1991                 config_item_name(&lun->lun_group.cg_item),
1992                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1993                 tg_pt_gp_new->tg_pt_gp_id);
1994
1995         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1996         return count;
1997 }
1998
1999 ssize_t core_alua_show_access_type(
2000         struct t10_alua_tg_pt_gp *tg_pt_gp,
2001         char *page)
2002 {
2003         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2004             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2005                 return sprintf(page, "Implicit and Explicit\n");
2006         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2007                 return sprintf(page, "Implicit\n");
2008         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2009                 return sprintf(page, "Explicit\n");
2010         else
2011                 return sprintf(page, "None\n");
2012 }
2013
2014 ssize_t core_alua_store_access_type(
2015         struct t10_alua_tg_pt_gp *tg_pt_gp,
2016         const char *page,
2017         size_t count)
2018 {
2019         unsigned long tmp;
2020         int ret;
2021
2022         ret = kstrtoul(page, 0, &tmp);
2023         if (ret < 0) {
2024                 pr_err("Unable to extract alua_access_type\n");
2025                 return ret;
2026         }
2027         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2028                 pr_err("Illegal value for alua_access_type:"
2029                                 " %lu\n", tmp);
2030                 return -EINVAL;
2031         }
2032         if (tmp == 3)
2033                 tg_pt_gp->tg_pt_gp_alua_access_type =
2034                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2035         else if (tmp == 2)
2036                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2037         else if (tmp == 1)
2038                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2039         else
2040                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2041
2042         return count;
2043 }
2044
2045 ssize_t core_alua_show_nonop_delay_msecs(
2046         struct t10_alua_tg_pt_gp *tg_pt_gp,
2047         char *page)
2048 {
2049         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2050 }
2051
2052 ssize_t core_alua_store_nonop_delay_msecs(
2053         struct t10_alua_tg_pt_gp *tg_pt_gp,
2054         const char *page,
2055         size_t count)
2056 {
2057         unsigned long tmp;
2058         int ret;
2059
2060         ret = kstrtoul(page, 0, &tmp);
2061         if (ret < 0) {
2062                 pr_err("Unable to extract nonop_delay_msecs\n");
2063                 return ret;
2064         }
2065         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2066                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2067                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2068                         ALUA_MAX_NONOP_DELAY_MSECS);
2069                 return -EINVAL;
2070         }
2071         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2072
2073         return count;
2074 }
2075
2076 ssize_t core_alua_show_trans_delay_msecs(
2077         struct t10_alua_tg_pt_gp *tg_pt_gp,
2078         char *page)
2079 {
2080         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2081 }
2082
2083 ssize_t core_alua_store_trans_delay_msecs(
2084         struct t10_alua_tg_pt_gp *tg_pt_gp,
2085         const char *page,
2086         size_t count)
2087 {
2088         unsigned long tmp;
2089         int ret;
2090
2091         ret = kstrtoul(page, 0, &tmp);
2092         if (ret < 0) {
2093                 pr_err("Unable to extract trans_delay_msecs\n");
2094                 return ret;
2095         }
2096         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2097                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2098                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2099                         ALUA_MAX_TRANS_DELAY_MSECS);
2100                 return -EINVAL;
2101         }
2102         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2103
2104         return count;
2105 }
2106
2107 ssize_t core_alua_show_implicit_trans_secs(
2108         struct t10_alua_tg_pt_gp *tg_pt_gp,
2109         char *page)
2110 {
2111         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2112 }
2113
2114 ssize_t core_alua_store_implicit_trans_secs(
2115         struct t10_alua_tg_pt_gp *tg_pt_gp,
2116         const char *page,
2117         size_t count)
2118 {
2119         unsigned long tmp;
2120         int ret;
2121
2122         ret = kstrtoul(page, 0, &tmp);
2123         if (ret < 0) {
2124                 pr_err("Unable to extract implicit_trans_secs\n");
2125                 return ret;
2126         }
2127         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2128                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2129                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2130                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2131                 return  -EINVAL;
2132         }
2133         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2134
2135         return count;
2136 }
2137
2138 ssize_t core_alua_show_preferred_bit(
2139         struct t10_alua_tg_pt_gp *tg_pt_gp,
2140         char *page)
2141 {
2142         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2143 }
2144
2145 ssize_t core_alua_store_preferred_bit(
2146         struct t10_alua_tg_pt_gp *tg_pt_gp,
2147         const char *page,
2148         size_t count)
2149 {
2150         unsigned long tmp;
2151         int ret;
2152
2153         ret = kstrtoul(page, 0, &tmp);
2154         if (ret < 0) {
2155                 pr_err("Unable to extract preferred ALUA value\n");
2156                 return ret;
2157         }
2158         if ((tmp != 0) && (tmp != 1)) {
2159                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2160                 return -EINVAL;
2161         }
2162         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2163
2164         return count;
2165 }
2166
2167 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2168 {
2169         return sprintf(page, "%d\n",
2170                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2171 }
2172
2173 ssize_t core_alua_store_offline_bit(
2174         struct se_lun *lun,
2175         const char *page,
2176         size_t count)
2177 {
2178         /*
2179          * rcu_dereference_raw protected by se_lun->lun_group symlink
2180          * reference to se_device->dev_group.
2181          */
2182         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2183         unsigned long tmp;
2184         int ret;
2185
2186         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2187             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2188                 return -ENODEV;
2189
2190         ret = kstrtoul(page, 0, &tmp);
2191         if (ret < 0) {
2192                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2193                 return ret;
2194         }
2195         if ((tmp != 0) && (tmp != 1)) {
2196                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2197                                 tmp);
2198                 return -EINVAL;
2199         }
2200
2201         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2202         if (ret < 0)
2203                 return -EINVAL;
2204
2205         return count;
2206 }
2207
2208 ssize_t core_alua_show_secondary_status(
2209         struct se_lun *lun,
2210         char *page)
2211 {
2212         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2213 }
2214
2215 ssize_t core_alua_store_secondary_status(
2216         struct se_lun *lun,
2217         const char *page,
2218         size_t count)
2219 {
2220         unsigned long tmp;
2221         int ret;
2222
2223         ret = kstrtoul(page, 0, &tmp);
2224         if (ret < 0) {
2225                 pr_err("Unable to extract alua_tg_pt_status\n");
2226                 return ret;
2227         }
2228         if ((tmp != ALUA_STATUS_NONE) &&
2229             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2230             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2231                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2232                                 tmp);
2233                 return -EINVAL;
2234         }
2235         lun->lun_tg_pt_secondary_stat = (int)tmp;
2236
2237         return count;
2238 }
2239
2240 ssize_t core_alua_show_secondary_write_metadata(
2241         struct se_lun *lun,
2242         char *page)
2243 {
2244         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2245 }
2246
2247 ssize_t core_alua_store_secondary_write_metadata(
2248         struct se_lun *lun,
2249         const char *page,
2250         size_t count)
2251 {
2252         unsigned long tmp;
2253         int ret;
2254
2255         ret = kstrtoul(page, 0, &tmp);
2256         if (ret < 0) {
2257                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2258                 return ret;
2259         }
2260         if ((tmp != 0) && (tmp != 1)) {
2261                 pr_err("Illegal value for alua_tg_pt_write_md:"
2262                                 " %lu\n", tmp);
2263                 return -EINVAL;
2264         }
2265         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2266
2267         return count;
2268 }
2269
2270 int core_setup_alua(struct se_device *dev)
2271 {
2272         if (!(dev->transport->transport_flags &
2273              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2274             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2275                 struct t10_alua_lu_gp_member *lu_gp_mem;
2276
2277                 /*
2278                  * Associate this struct se_device with the default ALUA
2279                  * LUN Group.
2280                  */
2281                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2282                 if (IS_ERR(lu_gp_mem))
2283                         return PTR_ERR(lu_gp_mem);
2284
2285                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2286                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2287                                 default_lu_gp);
2288                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2289
2290                 pr_debug("%s: Adding to default ALUA LU Group:"
2291                         " core/alua/lu_gps/default_lu_gp\n",
2292                         dev->transport->name);
2293         }
2294
2295         return 0;
2296 }