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  * Copyright (c) 2009-2010 Rising Tide Systems
   7  * Copyright (c) 2009-2010 Linux-iSCSI.org
   8  *
   9  * Nicholas A. Bellinger <nab@kernel.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  *
  25  ******************************************************************************/
  26
  27 #include <linux/slab.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/configfs.h>
  30 #include <scsi/scsi.h>
  31 #include <scsi/scsi_cmnd.h>
  32
  33 #include <target/target_core_base.h>
  34 #include <target/target_core_device.h>
  35 #include <target/target_core_transport.h>
  36 #include <target/target_core_fabric_ops.h>
  37 #include <target/target_core_configfs.h>
  38
  39 #include "target_core_alua.h"
  40 #include "target_core_hba.h"
  41 #include "target_core_ua.h"
  42
  43 static int core_alua_check_transition(int state, int *primary);
  44 static int core_alua_set_tg_pt_secondary_state(
  45                 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
  46                 struct se_port *port, int explict, int offline);
  47
  48 static u16 alua_lu_gps_counter;
  49 static u32 alua_lu_gps_count;
  50
  51 static DEFINE_SPINLOCK(lu_gps_lock);
  52 static LIST_HEAD(lu_gps_list);
  53
  54 struct t10_alua_lu_gp *default_lu_gp;
  55
  56 /*
  57  * REPORT_TARGET_PORT_GROUPS
  58  *
  59  * See spc4r17 section 6.27
  60  */
  61 int core_emulate_report_target_port_groups(struct se_cmd *cmd)
  62 {
  63         struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
  64         struct se_port *port;
  65         struct t10_alua_tg_pt_gp *tg_pt_gp;
  66         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
  67         unsigned char *buf;
  68         u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
  69                                     Target port group descriptor */
  70
  71         buf = transport_kmap_first_data_page(cmd);
  72
  73         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
  74         list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
  75                         tg_pt_gp_list) {
  76                 /*
  77                  * PREF: Preferred target port bit, determine if this
  78                  * bit should be set for port group.
  79                  */
  80                 if (tg_pt_gp->tg_pt_gp_pref)
  81                         buf[off] = 0x80;
  82                 /*
  83                  * Set the ASYMMETRIC ACCESS State
  84                  */
  85                 buf[off++] |= (atomic_read(
  86                         &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
  87                 /*
  88                  * Set supported ASYMMETRIC ACCESS State bits
  89                  */
  90                 buf[off] = 0x80; /* T_SUP */
  91                 buf[off] |= 0x40; /* O_SUP */
  92                 buf[off] |= 0x8; /* U_SUP */
  93                 buf[off] |= 0x4; /* S_SUP */
  94                 buf[off] |= 0x2; /* AN_SUP */
  95                 buf[off++] |= 0x1; /* AO_SUP */
  96                 /*
  97                  * TARGET PORT GROUP
  98                  */
  99                 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
 100                 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
 101
 102                 off++; /* Skip over Reserved */
 103                 /*
 104                  * STATUS CODE
 105                  */
 106                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 107                 /*
 108                  * Vendor Specific field
 109                  */
 110                 buf[off++] = 0x00;
 111                 /*
 112                  * TARGET PORT COUNT
 113                  */
 114                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 115                 rd_len += 8;
 116
 117                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 118                 list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
 119                                 tg_pt_gp_mem_list) {
 120                         port = tg_pt_gp_mem->tg_pt;
 121                         /*
 122                          * Start Target Port descriptor format
 123                          *
 124                          * See spc4r17 section 6.2.7 Table 247
 125                          */
 126                         off += 2; /* Skip over Obsolete */
 127                         /*
 128                          * Set RELATIVE TARGET PORT IDENTIFIER
 129                          */
 130                         buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
 131                         buf[off++] = (port->sep_rtpi & 0xff);
 132                         rd_len += 4;
 133                 }
 134                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 135         }
 136         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 137         /*
 138          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 139          */
 140         buf[0] = ((rd_len >> 24) & 0xff);
 141         buf[1] = ((rd_len >> 16) & 0xff);
 142         buf[2] = ((rd_len >> 8) & 0xff);
 143         buf[3] = (rd_len & 0xff);
 144
 145         transport_kunmap_first_data_page(cmd);
 146
 147         return 0;
 148 }
 149
 150 /*
 151  * SET_TARGET_PORT_GROUPS for explict ALUA operation.
 152  *
 153  * See spc4r17 section 6.35
 154  */
 155 int core_emulate_set_target_port_groups(struct se_cmd *cmd)
 156 {
 157         struct se_device *dev = cmd->se_dev;
 158         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
 159         struct se_port *port, *l_port = cmd->se_lun->lun_sep;
 160         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 161         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 162         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
 163         unsigned char *buf;
 164         unsigned char *ptr;
 165         u32 len = 4; /* Skip over RESERVED area in header */
 166         int alua_access_state, primary = 0, rc;
 167         u16 tg_pt_id, rtpi;
 168
 169         if (!l_port)
 170                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 171
 172         buf = transport_kmap_first_data_page(cmd);
 173
 174         /*
 175          * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
 176          * for the local tg_pt_gp.
 177          */
 178         l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
 179         if (!l_tg_pt_gp_mem) {
 180                 pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
 181                 rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 182                 goto out;
 183         }
 184         spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 185         l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
 186         if (!l_tg_pt_gp) {
 187                 spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 188                 pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
 189                 rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 190                 goto out;
 191         }
 192         rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
 193         spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 194
 195         if (!rc) {
 196                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 197                                 " while TPGS_EXPLICT_ALUA is disabled\n");
 198                 rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 199                 goto out;
 200         }
 201
 202         ptr = &buf[4]; /* Skip over RESERVED area in header */
 203
 204         while (len < cmd->data_length) {
 205                 alua_access_state = (ptr[0] & 0x0f);
 206                 /*
 207                  * Check the received ALUA access state, and determine if
 208                  * the state is a primary or secondary target port asymmetric
 209                  * access state.
 210                  */
 211                 rc = core_alua_check_transition(alua_access_state, &primary);
 212                 if (rc != 0) {
 213                         /*
 214                          * If the SET TARGET PORT GROUPS attempts to establish
 215                          * an invalid combination of target port asymmetric
 216                          * access states or attempts to establish an
 217                          * unsupported target port asymmetric access state,
 218                          * then the command shall be terminated with CHECK
 219                          * CONDITION status, with the sense key set to ILLEGAL
 220                          * REQUEST, and the additional sense code set to INVALID
 221                          * FIELD IN PARAMETER LIST.
 222                          */
 223                         rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 224                         goto out;
 225                 }
 226                 rc = -1;
 227                 /*
 228                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 229                  * specifies a primary target port asymmetric access state,
 230                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 231                  * a primary target port group for which the primary target
 232                  * port asymmetric access state shall be changed. If the
 233                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 234                  * port asymmetric access state, then the TARGET PORT GROUP OR
 235                  * TARGET PORT field specifies the relative target port
 236                  * identifier (see 3.1.120) of the target port for which the
 237                  * secondary target port asymmetric access state shall be
 238                  * changed.
 239                  */
 240                 if (primary) {
 241                         tg_pt_id = ((ptr[2] << 8) & 0xff);
 242                         tg_pt_id |= (ptr[3] & 0xff);
 243                         /*
 244                          * Locate the matching target port group ID from
 245                          * the global tg_pt_gp list
 246                          */
 247                         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 248                         list_for_each_entry(tg_pt_gp,
 249                                         &su_dev->t10_alua.tg_pt_gps_list,
 250                                         tg_pt_gp_list) {
 251                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 252                                         continue;
 253
 254                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 255                                         continue;
 256
 257                                 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 258                                 smp_mb__after_atomic_inc();
 259                                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 260
 261                                 rc = core_alua_do_port_transition(tg_pt_gp,
 262                                                 dev, l_port, nacl,
 263                                                 alua_access_state, 1);
 264
 265                                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 266                                 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 267                                 smp_mb__after_atomic_dec();
 268                                 break;
 269                         }
 270                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 271                         /*
 272                          * If not matching target port group ID can be located
 273                          * throw an exception with ASCQ: INVALID_PARAMETER_LIST
 274                          */
 275                         if (rc != 0) {
 276                                 rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 277                                 goto out;
 278                         }
 279                 } else {
 280                         /*
 281                          * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
 282                          * the Target Port in question for the the incoming
 283                          * SET_TARGET_PORT_GROUPS op.
 284                          */
 285                         rtpi = ((ptr[2] << 8) & 0xff);
 286                         rtpi |= (ptr[3] & 0xff);
 287                         /*
 288                          * Locate the matching relative target port identifer
 289                          * for the struct se_device storage object.
 290                          */
 291                         spin_lock(&dev->se_port_lock);
 292                         list_for_each_entry(port, &dev->dev_sep_list,
 293                                                         sep_list) {
 294                                 if (port->sep_rtpi != rtpi)
 295                                         continue;
 296
 297                                 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 298                                 spin_unlock(&dev->se_port_lock);
 299
 300                                 rc = core_alua_set_tg_pt_secondary_state(
 301                                                 tg_pt_gp_mem, port, 1, 1);
 302
 303                                 spin_lock(&dev->se_port_lock);
 304                                 break;
 305                         }
 306                         spin_unlock(&dev->se_port_lock);
 307                         /*
 308                          * If not matching relative target port identifier can
 309                          * be located, throw an exception with ASCQ:
 310                          * INVALID_PARAMETER_LIST
 311                          */
 312                         if (rc != 0) {
 313                                 rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 314                                 goto out;
 315                         }
 316                 }
 317
 318                 ptr += 4;
 319                 len += 4;
 320         }
 321
 322 out:
 323         transport_kunmap_first_data_page(cmd);
 324
 325         return 0;
 326 }
 327
 328 static inline int core_alua_state_nonoptimized(
 329         struct se_cmd *cmd,
 330         unsigned char *cdb,
 331         int nonop_delay_msecs,
 332         u8 *alua_ascq)
 333 {
 334         /*
 335          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 336          * later to determine if processing of this cmd needs to be
 337          * temporarily delayed for the Active/NonOptimized primary access state.
 338          */
 339         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 340         cmd->alua_nonop_delay = nonop_delay_msecs;
 341         return 0;
 342 }
 343
 344 static inline int core_alua_state_standby(
 345         struct se_cmd *cmd,
 346         unsigned char *cdb,
 347         u8 *alua_ascq)
 348 {
 349         /*
 350          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 351          * spc4r17 section 5.9.2.4.4
 352          */
 353         switch (cdb[0]) {
 354         case INQUIRY:
 355         case LOG_SELECT:
 356         case LOG_SENSE:
 357         case MODE_SELECT:
 358         case MODE_SENSE:
 359         case REPORT_LUNS:
 360         case RECEIVE_DIAGNOSTIC:
 361         case SEND_DIAGNOSTIC:
 362         case MAINTENANCE_IN:
 363                 switch (cdb[1]) {
 364                 case MI_REPORT_TARGET_PGS:
 365                         return 0;
 366                 default:
 367                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 368                         return 1;
 369                 }
 370         case MAINTENANCE_OUT:
 371                 switch (cdb[1]) {
 372                 case MO_SET_TARGET_PGS:
 373                         return 0;
 374                 default:
 375                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 376                         return 1;
 377                 }
 378         case REQUEST_SENSE:
 379         case PERSISTENT_RESERVE_IN:
 380         case PERSISTENT_RESERVE_OUT:
 381         case READ_BUFFER:
 382         case WRITE_BUFFER:
 383                 return 0;
 384         default:
 385                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 386                 return 1;
 387         }
 388
 389         return 0;
 390 }
 391
 392 static inline int core_alua_state_unavailable(
 393         struct se_cmd *cmd,
 394         unsigned char *cdb,
 395         u8 *alua_ascq)
 396 {
 397         /*
 398          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 399          * spc4r17 section 5.9.2.4.5
 400          */
 401         switch (cdb[0]) {
 402         case INQUIRY:
 403         case REPORT_LUNS:
 404         case MAINTENANCE_IN:
 405                 switch (cdb[1]) {
 406                 case MI_REPORT_TARGET_PGS:
 407                         return 0;
 408                 default:
 409                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 410                         return 1;
 411                 }
 412         case MAINTENANCE_OUT:
 413                 switch (cdb[1]) {
 414                 case MO_SET_TARGET_PGS:
 415                         return 0;
 416                 default:
 417                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 418                         return 1;
 419                 }
 420         case REQUEST_SENSE:
 421         case READ_BUFFER:
 422         case WRITE_BUFFER:
 423                 return 0;
 424         default:
 425                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 426                 return 1;
 427         }
 428
 429         return 0;
 430 }
 431
 432 static inline int core_alua_state_transition(
 433         struct se_cmd *cmd,
 434         unsigned char *cdb,
 435         u8 *alua_ascq)
 436 {
 437         /*
 438          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
 439          * spc4r17 section 5.9.2.5
 440          */
 441         switch (cdb[0]) {
 442         case INQUIRY:
 443         case REPORT_LUNS:
 444         case MAINTENANCE_IN:
 445                 switch (cdb[1]) {
 446                 case MI_REPORT_TARGET_PGS:
 447                         return 0;
 448                 default:
 449                         *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 450                         return 1;
 451                 }
 452         case REQUEST_SENSE:
 453         case READ_BUFFER:
 454         case WRITE_BUFFER:
 455                 return 0;
 456         default:
 457                 *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 458                 return 1;
 459         }
 460
 461         return 0;
 462 }
 463
 464 /*
 465  * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
 466  * in transport_cmd_sequencer().  This function is assigned to
 467  * struct t10_alua *->state_check() in core_setup_alua()
 468  */
 469 static int core_alua_state_check_nop(
 470         struct se_cmd *cmd,
 471         unsigned char *cdb,
 472         u8 *alua_ascq)
 473 {
 474         return 0;
 475 }
 476
 477 /*
 478  * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
 479  * This function is assigned to struct t10_alua *->state_check() in
 480  * core_setup_alua()
 481  *
 482  * Also, this function can return three different return codes to
 483  * signal transport_generic_cmd_sequencer()
 484  *
 485  * return 1: Is used to signal LUN not accecsable, and check condition/not ready
 486  * return 0: Used to signal success
 487  * reutrn -1: Used to signal failure, and invalid cdb field
 488  */
 489 static int core_alua_state_check(
 490         struct se_cmd *cmd,
 491         unsigned char *cdb,
 492         u8 *alua_ascq)
 493 {
 494         struct se_lun *lun = cmd->se_lun;
 495         struct se_port *port = lun->lun_sep;
 496         struct t10_alua_tg_pt_gp *tg_pt_gp;
 497         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
 498         int out_alua_state, nonop_delay_msecs;
 499
 500         if (!port)
 501                 return 0;
 502         /*
 503          * First, check for a struct se_port specific secondary ALUA target port
 504          * access state: OFFLINE
 505          */
 506         if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
 507                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 508                 pr_debug("ALUA: Got secondary offline status for local"
 509                                 " target port\n");
 510                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 511                 return 1;
 512         }
 513          /*
 514          * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
 515          * ALUA target port group, to obtain current ALUA access state.
 516          * Otherwise look for the underlying struct se_device association with
 517          * a ALUA logical unit group.
 518          */
 519         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 520         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 521         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
 522         out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 523         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 524         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 525         /*
 526          * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a separate conditional
 527          * statement so the compiler knows explicitly to check this case first.
 528          * For the Optimized ALUA access state case, we want to process the
 529          * incoming fabric cmd ASAP..
 530          */
 531         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
 532                 return 0;
 533
 534         switch (out_alua_state) {
 535         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 536                 return core_alua_state_nonoptimized(cmd, cdb,
 537                                         nonop_delay_msecs, alua_ascq);
 538         case ALUA_ACCESS_STATE_STANDBY:
 539                 return core_alua_state_standby(cmd, cdb, alua_ascq);
 540         case ALUA_ACCESS_STATE_UNAVAILABLE:
 541                 return core_alua_state_unavailable(cmd, cdb, alua_ascq);
 542         case ALUA_ACCESS_STATE_TRANSITION:
 543                 return core_alua_state_transition(cmd, cdb, alua_ascq);
 544         /*
 545          * OFFLINE is a secondary ALUA target port group access state, that is
 546          * handled above with struct se_port->sep_tg_pt_secondary_offline=1
 547          */
 548         case ALUA_ACCESS_STATE_OFFLINE:
 549         default:
 550                 pr_err("Unknown ALUA access state: 0x%02x\n",
 551                                 out_alua_state);
 552                 return -EINVAL;
 553         }
 554
 555         return 0;
 556 }
 557
 558 /*
 559  * Check implict and explict ALUA state change request.
 560  */
 561 static int core_alua_check_transition(int state, int *primary)
 562 {
 563         switch (state) {
 564         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 565         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 566         case ALUA_ACCESS_STATE_STANDBY:
 567         case ALUA_ACCESS_STATE_UNAVAILABLE:
 568                 /*
 569                  * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 570                  * defined as primary target port asymmetric access states.
 571                  */
 572                 *primary = 1;
 573                 break;
 574         case ALUA_ACCESS_STATE_OFFLINE:
 575                 /*
 576                  * OFFLINE state is defined as a secondary target port
 577                  * asymmetric access state.
 578                  */
 579                 *primary = 0;
 580                 break;
 581         default:
 582                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 583                 return -EINVAL;
 584         }
 585
 586         return 0;
 587 }
 588
 589 static char *core_alua_dump_state(int state)
 590 {
 591         switch (state) {
 592         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 593                 return "Active/Optimized";
 594         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 595                 return "Active/NonOptimized";
 596         case ALUA_ACCESS_STATE_STANDBY:
 597                 return "Standby";
 598         case ALUA_ACCESS_STATE_UNAVAILABLE:
 599                 return "Unavailable";
 600         case ALUA_ACCESS_STATE_OFFLINE:
 601                 return "Offline";
 602         default:
 603                 return "Unknown";
 604         }
 605
 606         return NULL;
 607 }
 608
 609 char *core_alua_dump_status(int status)
 610 {
 611         switch (status) {
 612         case ALUA_STATUS_NONE:
 613                 return "None";
 614         case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
 615                 return "Altered by Explict STPG";
 616         case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
 617                 return "Altered by Implict ALUA";
 618         default:
 619                 return "Unknown";
 620         }
 621
 622         return NULL;
 623 }
 624
 625 /*
 626  * Used by fabric modules to determine when we need to delay processing
 627  * for the Active/NonOptimized paths..
 628  */
 629 int core_alua_check_nonop_delay(
 630         struct se_cmd *cmd)
 631 {
 632         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 633                 return 0;
 634         if (in_interrupt())
 635                 return 0;
 636         /*
 637          * The ALUA Active/NonOptimized access state delay can be disabled
 638          * in via configfs with a value of zero
 639          */
 640         if (!cmd->alua_nonop_delay)
 641                 return 0;
 642         /*
 643          * struct se_cmd->alua_nonop_delay gets set by a target port group
 644          * defined interval in core_alua_state_nonoptimized()
 645          */
 646         msleep_interruptible(cmd->alua_nonop_delay);
 647         return 0;
 648 }
 649 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 650
 651 /*
 652  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
 653  *
 654  */
 655 static int core_alua_write_tpg_metadata(
 656         const char *path,
 657         unsigned char *md_buf,
 658         u32 md_buf_len)
 659 {
 660         mm_segment_t old_fs;
 661         struct file *file;
 662         struct iovec iov[1];
 663         int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
 664
 665         memset(iov, 0, sizeof(struct iovec));
 666
 667         file = filp_open(path, flags, 0600);
 668         if (IS_ERR(file) || !file || !file->f_dentry) {
 669                 pr_err("filp_open(%s) for ALUA metadata failed\n",
 670                         path);
 671                 return -ENODEV;
 672         }
 673
 674         iov[0].iov_base = &md_buf[0];
 675         iov[0].iov_len = md_buf_len;
 676
 677         old_fs = get_fs();
 678         set_fs(get_ds());
 679         ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
 680         set_fs(old_fs);
 681
 682         if (ret < 0) {
 683                 pr_err("Error writing ALUA metadata file: %s\n", path);
 684                 filp_close(file, NULL);
 685                 return -EIO;
 686         }
 687         filp_close(file, NULL);
 688
 689         return 0;
 690 }
 691
 692 /*
 693  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
 694  */
 695 static int core_alua_update_tpg_primary_metadata(
 696         struct t10_alua_tg_pt_gp *tg_pt_gp,
 697         int primary_state,
 698         unsigned char *md_buf)
 699 {
 700         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
 701         struct t10_wwn *wwn = &su_dev->t10_wwn;
 702         char path[ALUA_METADATA_PATH_LEN];
 703         int len;
 704
 705         memset(path, 0, ALUA_METADATA_PATH_LEN);
 706
 707         len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
 708                         "tg_pt_gp_id=%hu\n"
 709                         "alua_access_state=0x%02x\n"
 710                         "alua_access_status=0x%02x\n",
 711                         tg_pt_gp->tg_pt_gp_id, primary_state,
 712                         tg_pt_gp->tg_pt_gp_alua_access_status);
 713
 714         snprintf(path, ALUA_METADATA_PATH_LEN,
 715                 "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
 716                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 717
 718         return core_alua_write_tpg_metadata(path, md_buf, len);
 719 }
 720
 721 static int core_alua_do_transition_tg_pt(
 722         struct t10_alua_tg_pt_gp *tg_pt_gp,
 723         struct se_port *l_port,
 724         struct se_node_acl *nacl,
 725         unsigned char *md_buf,
 726         int new_state,
 727         int explict)
 728 {
 729         struct se_dev_entry *se_deve;
 730         struct se_lun_acl *lacl;
 731         struct se_port *port;
 732         struct t10_alua_tg_pt_gp_member *mem;
 733         int old_state = 0;
 734         /*
 735          * Save the old primary ALUA access state, and set the current state
 736          * to ALUA_ACCESS_STATE_TRANSITION.
 737          */
 738         old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 739         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
 740                         ALUA_ACCESS_STATE_TRANSITION);
 741         tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
 742                                 ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
 743                                 ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
 744         /*
 745          * Check for the optional ALUA primary state transition delay
 746          */
 747         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
 748                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
 749
 750         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 751         list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
 752                                 tg_pt_gp_mem_list) {
 753                 port = mem->tg_pt;
 754                 /*
 755                  * After an implicit target port asymmetric access state
 756                  * change, a device server shall establish a unit attention
 757                  * condition for the initiator port associated with every I_T
 758                  * nexus with the additional sense code set to ASYMMETRIC
 759                  * ACCESS STATE CHAGED.
 760                  *
 761                  * After an explicit target port asymmetric access state
 762                  * change, a device server shall establish a unit attention
 763                  * condition with the additional sense code set to ASYMMETRIC
 764                  * ACCESS STATE CHANGED for the initiator port associated with
 765                  * every I_T nexus other than the I_T nexus on which the SET
 766                  * TARGET PORT GROUPS command
 767                  */
 768                 atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
 769                 smp_mb__after_atomic_inc();
 770                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 771
 772                 spin_lock_bh(&port->sep_alua_lock);
 773                 list_for_each_entry(se_deve, &port->sep_alua_list,
 774                                         alua_port_list) {
 775                         lacl = se_deve->se_lun_acl;
 776                         /*
 777                          * se_deve->se_lun_acl pointer may be NULL for a
 778                          * entry created without explict Node+MappedLUN ACLs
 779                          */
 780                         if (!lacl)
 781                                 continue;
 782
 783                         if (explict &&
 784                            (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
 785                            (l_port != NULL) && (l_port == port))
 786                                 continue;
 787
 788                         core_scsi3_ua_allocate(lacl->se_lun_nacl,
 789                                 se_deve->mapped_lun, 0x2A,
 790                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
 791                 }
 792                 spin_unlock_bh(&port->sep_alua_lock);
 793
 794                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 795                 atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
 796                 smp_mb__after_atomic_dec();
 797         }
 798         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 799         /*
 800          * Update the ALUA metadata buf that has been allocated in
 801          * core_alua_do_port_transition(), this metadata will be written
 802          * to struct file.
 803          *
 804          * Note that there is the case where we do not want to update the
 805          * metadata when the saved metadata is being parsed in userspace
 806          * when setting the existing port access state and access status.
 807          *
 808          * Also note that the failure to write out the ALUA metadata to
 809          * struct file does NOT affect the actual ALUA transition.
 810          */
 811         if (tg_pt_gp->tg_pt_gp_write_metadata) {
 812                 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
 813                 core_alua_update_tpg_primary_metadata(tg_pt_gp,
 814                                         new_state, md_buf);
 815                 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
 816         }
 817         /*
 818          * Set the current primary ALUA access state to the requested new state
 819          */
 820         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
 821
 822         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
 823                 " from primary access state %s to %s\n", (explict) ? "explict" :
 824                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
 825                 tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
 826                 core_alua_dump_state(new_state));
 827
 828         return 0;
 829 }
 830
 831 int core_alua_do_port_transition(
 832         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
 833         struct se_device *l_dev,
 834         struct se_port *l_port,
 835         struct se_node_acl *l_nacl,
 836         int new_state,
 837         int explict)
 838 {
 839         struct se_device *dev;
 840         struct se_port *port;
 841         struct se_subsystem_dev *su_dev;
 842         struct se_node_acl *nacl;
 843         struct t10_alua_lu_gp *lu_gp;
 844         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
 845         struct t10_alua_tg_pt_gp *tg_pt_gp;
 846         unsigned char *md_buf;
 847         int primary;
 848
 849         if (core_alua_check_transition(new_state, &primary) != 0)
 850                 return -EINVAL;
 851
 852         md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
 853         if (!md_buf) {
 854                 pr_err("Unable to allocate buf for ALUA metadata\n");
 855                 return -ENOMEM;
 856         }
 857
 858         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
 859         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
 860         lu_gp = local_lu_gp_mem->lu_gp;
 861         atomic_inc(&lu_gp->lu_gp_ref_cnt);
 862         smp_mb__after_atomic_inc();
 863         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
 864         /*
 865          * For storage objects that are members of the 'default_lu_gp',
 866          * we only do transition on the passed *l_tp_pt_gp, and not
 867          * on all of the matching target port groups IDs in default_lu_gp.
 868          */
 869         if (!lu_gp->lu_gp_id) {
 870                 /*
 871                  * core_alua_do_transition_tg_pt() will always return
 872                  * success.
 873                  */
 874                 core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
 875                                         md_buf, new_state, explict);
 876                 atomic_dec(&lu_gp->lu_gp_ref_cnt);
 877                 smp_mb__after_atomic_dec();
 878                 kfree(md_buf);
 879                 return 0;
 880         }
 881         /*
 882          * For all other LU groups aside from 'default_lu_gp', walk all of
 883          * the associated storage objects looking for a matching target port
 884          * group ID from the local target port group.
 885          */
 886         spin_lock(&lu_gp->lu_gp_lock);
 887         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
 888                                 lu_gp_mem_list) {
 889
 890                 dev = lu_gp_mem->lu_gp_mem_dev;
 891                 su_dev = dev->se_sub_dev;
 892                 atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
 893                 smp_mb__after_atomic_inc();
 894                 spin_unlock(&lu_gp->lu_gp_lock);
 895
 896                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 897                 list_for_each_entry(tg_pt_gp,
 898                                 &su_dev->t10_alua.tg_pt_gps_list,
 899                                 tg_pt_gp_list) {
 900
 901                         if (!tg_pt_gp->tg_pt_gp_valid_id)
 902                                 continue;
 903                         /*
 904                          * If the target behavior port asymmetric access state
 905                          * is changed for any target port group accessiable via
 906                          * a logical unit within a LU group, the target port
 907                          * behavior group asymmetric access states for the same
 908                          * target port group accessible via other logical units
 909                          * in that LU group will also change.
 910                          */
 911                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
 912                                 continue;
 913
 914                         if (l_tg_pt_gp == tg_pt_gp) {
 915                                 port = l_port;
 916                                 nacl = l_nacl;
 917                         } else {
 918                                 port = NULL;
 919                                 nacl = NULL;
 920                         }
 921                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 922                         smp_mb__after_atomic_inc();
 923                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 924                         /*
 925                          * core_alua_do_transition_tg_pt() will always return
 926                          * success.
 927                          */
 928                         core_alua_do_transition_tg_pt(tg_pt_gp, port,
 929                                         nacl, md_buf, new_state, explict);
 930
 931                         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 932                         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 933                         smp_mb__after_atomic_dec();
 934                 }
 935                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 936
 937                 spin_lock(&lu_gp->lu_gp_lock);
 938                 atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
 939                 smp_mb__after_atomic_dec();
 940         }
 941         spin_unlock(&lu_gp->lu_gp_lock);
 942
 943         pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
 944                 " Group IDs: %hu %s transition to primary state: %s\n",
 945                 config_item_name(&lu_gp->lu_gp_group.cg_item),
 946                 l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
 947                 core_alua_dump_state(new_state));
 948
 949         atomic_dec(&lu_gp->lu_gp_ref_cnt);
 950         smp_mb__after_atomic_dec();
 951         kfree(md_buf);
 952         return 0;
 953 }
 954
 955 /*
 956  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
 957  */
 958 static int core_alua_update_tpg_secondary_metadata(
 959         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 960         struct se_port *port,
 961         unsigned char *md_buf,
 962         u32 md_buf_len)
 963 {
 964         struct se_portal_group *se_tpg = port->sep_tpg;
 965         char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
 966         int len;
 967
 968         memset(path, 0, ALUA_METADATA_PATH_LEN);
 969         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
 970
 971         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
 972                         se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
 973
 974         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
 975                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
 976                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
 977
 978         len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
 979                         "alua_tg_pt_status=0x%02x\n",
 980                         atomic_read(&port->sep_tg_pt_secondary_offline),
 981                         port->sep_tg_pt_secondary_stat);
 982
 983         snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
 984                         se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
 985                         port->sep_lun->unpacked_lun);
 986
 987         return core_alua_write_tpg_metadata(path, md_buf, len);
 988 }
 989
 990 static int core_alua_set_tg_pt_secondary_state(
 991         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 992         struct se_port *port,
 993         int explict,
 994         int offline)
 995 {
 996         struct t10_alua_tg_pt_gp *tg_pt_gp;
 997         unsigned char *md_buf;
 998         u32 md_buf_len;
 999         int trans_delay_msecs;
1000
1001         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1002         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1003         if (!tg_pt_gp) {
1004                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1005                 pr_err("Unable to complete secondary state"
1006                                 " transition\n");
1007                 return -EINVAL;
1008         }
1009         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1010         /*
1011          * Set the secondary ALUA target port access state to OFFLINE
1012          * or release the previously secondary state for struct se_port
1013          */
1014         if (offline)
1015                 atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1016         else
1017                 atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1018
1019         md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
1020         port->sep_tg_pt_secondary_stat = (explict) ?
1021                         ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
1022                         ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
1023
1024         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1025                 " to secondary access state: %s\n", (explict) ? "explict" :
1026                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1027                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1028
1029         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1030         /*
1031          * Do the optional transition delay after we set the secondary
1032          * ALUA access state.
1033          */
1034         if (trans_delay_msecs != 0)
1035                 msleep_interruptible(trans_delay_msecs);
1036         /*
1037          * See if we need to update the ALUA fabric port metadata for
1038          * secondary state and status
1039          */
1040         if (port->sep_tg_pt_secondary_write_md) {
1041                 md_buf = kzalloc(md_buf_len, GFP_KERNEL);
1042                 if (!md_buf) {
1043                         pr_err("Unable to allocate md_buf for"
1044                                 " secondary ALUA access metadata\n");
1045                         return -ENOMEM;
1046                 }
1047                 mutex_lock(&port->sep_tg_pt_md_mutex);
1048                 core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
1049                                 md_buf, md_buf_len);
1050                 mutex_unlock(&port->sep_tg_pt_md_mutex);
1051
1052                 kfree(md_buf);
1053         }
1054
1055         return 0;
1056 }
1057
1058 struct t10_alua_lu_gp *
1059 core_alua_allocate_lu_gp(const char *name, int def_group)
1060 {
1061         struct t10_alua_lu_gp *lu_gp;
1062
1063         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1064         if (!lu_gp) {
1065                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1066                 return ERR_PTR(-ENOMEM);
1067         }
1068         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1069         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1070         spin_lock_init(&lu_gp->lu_gp_lock);
1071         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1072
1073         if (def_group) {
1074                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1075                 lu_gp->lu_gp_valid_id = 1;
1076                 alua_lu_gps_count++;
1077         }
1078
1079         return lu_gp;
1080 }
1081
1082 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1083 {
1084         struct t10_alua_lu_gp *lu_gp_tmp;
1085         u16 lu_gp_id_tmp;
1086         /*
1087          * The lu_gp->lu_gp_id may only be set once..
1088          */
1089         if (lu_gp->lu_gp_valid_id) {
1090                 pr_warn("ALUA LU Group already has a valid ID,"
1091                         " ignoring request\n");
1092                 return -EINVAL;
1093         }
1094
1095         spin_lock(&lu_gps_lock);
1096         if (alua_lu_gps_count == 0x0000ffff) {
1097                 pr_err("Maximum ALUA alua_lu_gps_count:"
1098                                 " 0x0000ffff reached\n");
1099                 spin_unlock(&lu_gps_lock);
1100                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1101                 return -ENOSPC;
1102         }
1103 again:
1104         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1105                                 alua_lu_gps_counter++;
1106
1107         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1108                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1109                         if (!lu_gp_id)
1110                                 goto again;
1111
1112                         pr_warn("ALUA Logical Unit Group ID: %hu"
1113                                 " already exists, ignoring request\n",
1114                                 lu_gp_id);
1115                         spin_unlock(&lu_gps_lock);
1116                         return -EINVAL;
1117                 }
1118         }
1119
1120         lu_gp->lu_gp_id = lu_gp_id_tmp;
1121         lu_gp->lu_gp_valid_id = 1;
1122         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1123         alua_lu_gps_count++;
1124         spin_unlock(&lu_gps_lock);
1125
1126         return 0;
1127 }
1128
1129 static struct t10_alua_lu_gp_member *
1130 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1131 {
1132         struct t10_alua_lu_gp_member *lu_gp_mem;
1133
1134         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1135         if (!lu_gp_mem) {
1136                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1137                 return ERR_PTR(-ENOMEM);
1138         }
1139         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1140         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1141         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1142
1143         lu_gp_mem->lu_gp_mem_dev = dev;
1144         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1145
1146         return lu_gp_mem;
1147 }
1148
1149 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1150 {
1151         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1152         /*
1153          * Once we have reached this point, config_item_put() has
1154          * already been called from target_core_alua_drop_lu_gp().
1155          *
1156          * Here, we remove the *lu_gp from the global list so that
1157          * no associations can be made while we are releasing
1158          * struct t10_alua_lu_gp.
1159          */
1160         spin_lock(&lu_gps_lock);
1161         atomic_set(&lu_gp->lu_gp_shutdown, 1);
1162         list_del(&lu_gp->lu_gp_node);
1163         alua_lu_gps_count--;
1164         spin_unlock(&lu_gps_lock);
1165         /*
1166          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1167          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1168          * released with core_alua_put_lu_gp_from_name()
1169          */
1170         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1171                 cpu_relax();
1172         /*
1173          * Release reference to struct t10_alua_lu_gp * from all associated
1174          * struct se_device.
1175          */
1176         spin_lock(&lu_gp->lu_gp_lock);
1177         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1178                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1179                 if (lu_gp_mem->lu_gp_assoc) {
1180                         list_del(&lu_gp_mem->lu_gp_mem_list);
1181                         lu_gp->lu_gp_members--;
1182                         lu_gp_mem->lu_gp_assoc = 0;
1183                 }
1184                 spin_unlock(&lu_gp->lu_gp_lock);
1185                 /*
1186                  *
1187                  * lu_gp_mem is associated with a single
1188                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1189                  * struct se_device is released via core_alua_free_lu_gp_mem().
1190                  *
1191                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1192                  * we want to re-assocate a given lu_gp_mem with default_lu_gp.
1193                  */
1194                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1195                 if (lu_gp != default_lu_gp)
1196                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1197                                         default_lu_gp);
1198                 else
1199                         lu_gp_mem->lu_gp = NULL;
1200                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1201
1202                 spin_lock(&lu_gp->lu_gp_lock);
1203         }
1204         spin_unlock(&lu_gp->lu_gp_lock);
1205
1206         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1207 }
1208
1209 void core_alua_free_lu_gp_mem(struct se_device *dev)
1210 {
1211         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1212         struct t10_alua *alua = &su_dev->t10_alua;
1213         struct t10_alua_lu_gp *lu_gp;
1214         struct t10_alua_lu_gp_member *lu_gp_mem;
1215
1216         if (alua->alua_type != SPC3_ALUA_EMULATED)
1217                 return;
1218
1219         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1220         if (!lu_gp_mem)
1221                 return;
1222
1223         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1224                 cpu_relax();
1225
1226         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1227         lu_gp = lu_gp_mem->lu_gp;
1228         if (lu_gp) {
1229                 spin_lock(&lu_gp->lu_gp_lock);
1230                 if (lu_gp_mem->lu_gp_assoc) {
1231                         list_del(&lu_gp_mem->lu_gp_mem_list);
1232                         lu_gp->lu_gp_members--;
1233                         lu_gp_mem->lu_gp_assoc = 0;
1234                 }
1235                 spin_unlock(&lu_gp->lu_gp_lock);
1236                 lu_gp_mem->lu_gp = NULL;
1237         }
1238         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1239
1240         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1241 }
1242
1243 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1244 {
1245         struct t10_alua_lu_gp *lu_gp;
1246         struct config_item *ci;
1247
1248         spin_lock(&lu_gps_lock);
1249         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1250                 if (!lu_gp->lu_gp_valid_id)
1251                         continue;
1252                 ci = &lu_gp->lu_gp_group.cg_item;
1253                 if (!strcmp(config_item_name(ci), name)) {
1254                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1255                         spin_unlock(&lu_gps_lock);
1256                         return lu_gp;
1257                 }
1258         }
1259         spin_unlock(&lu_gps_lock);
1260
1261         return NULL;
1262 }
1263
1264 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1265 {
1266         spin_lock(&lu_gps_lock);
1267         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1268         spin_unlock(&lu_gps_lock);
1269 }
1270
1271 /*
1272  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1273  */
1274 void __core_alua_attach_lu_gp_mem(
1275         struct t10_alua_lu_gp_member *lu_gp_mem,
1276         struct t10_alua_lu_gp *lu_gp)
1277 {
1278         spin_lock(&lu_gp->lu_gp_lock);
1279         lu_gp_mem->lu_gp = lu_gp;
1280         lu_gp_mem->lu_gp_assoc = 1;
1281         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1282         lu_gp->lu_gp_members++;
1283         spin_unlock(&lu_gp->lu_gp_lock);
1284 }
1285
1286 /*
1287  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1288  */
1289 void __core_alua_drop_lu_gp_mem(
1290         struct t10_alua_lu_gp_member *lu_gp_mem,
1291         struct t10_alua_lu_gp *lu_gp)
1292 {
1293         spin_lock(&lu_gp->lu_gp_lock);
1294         list_del(&lu_gp_mem->lu_gp_mem_list);
1295         lu_gp_mem->lu_gp = NULL;
1296         lu_gp_mem->lu_gp_assoc = 0;
1297         lu_gp->lu_gp_members--;
1298         spin_unlock(&lu_gp->lu_gp_lock);
1299 }
1300
1301 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
1302         struct se_subsystem_dev *su_dev,
1303         const char *name,
1304         int def_group)
1305 {
1306         struct t10_alua_tg_pt_gp *tg_pt_gp;
1307
1308         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1309         if (!tg_pt_gp) {
1310                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1311                 return NULL;
1312         }
1313         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1314         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1315         mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1316         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1317         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1318         tg_pt_gp->tg_pt_gp_su_dev = su_dev;
1319         tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
1320         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1321                 ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
1322         /*
1323          * Enable both explict and implict ALUA support by default
1324          */
1325         tg_pt_gp->tg_pt_gp_alua_access_type =
1326                         TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
1327         /*
1328          * Set the default Active/NonOptimized Delay in milliseconds
1329          */
1330         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1331         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1332
1333         if (def_group) {
1334                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1335                 tg_pt_gp->tg_pt_gp_id =
1336                                 su_dev->t10_alua.alua_tg_pt_gps_counter++;
1337                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1338                 su_dev->t10_alua.alua_tg_pt_gps_count++;
1339                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1340                               &su_dev->t10_alua.tg_pt_gps_list);
1341                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1342         }
1343
1344         return tg_pt_gp;
1345 }
1346
1347 int core_alua_set_tg_pt_gp_id(
1348         struct t10_alua_tg_pt_gp *tg_pt_gp,
1349         u16 tg_pt_gp_id)
1350 {
1351         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1352         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1353         u16 tg_pt_gp_id_tmp;
1354         /*
1355          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1356          */
1357         if (tg_pt_gp->tg_pt_gp_valid_id) {
1358                 pr_warn("ALUA TG PT Group already has a valid ID,"
1359                         " ignoring request\n");
1360                 return -EINVAL;
1361         }
1362
1363         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1364         if (su_dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1365                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1366                         " 0x0000ffff reached\n");
1367                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1368                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1369                 return -ENOSPC;
1370         }
1371 again:
1372         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1373                         su_dev->t10_alua.alua_tg_pt_gps_counter++;
1374
1375         list_for_each_entry(tg_pt_gp_tmp, &su_dev->t10_alua.tg_pt_gps_list,
1376                         tg_pt_gp_list) {
1377                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1378                         if (!tg_pt_gp_id)
1379                                 goto again;
1380
1381                         pr_err("ALUA Target Port Group ID: %hu already"
1382                                 " exists, ignoring request\n", tg_pt_gp_id);
1383                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1384                         return -EINVAL;
1385                 }
1386         }
1387
1388         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1389         tg_pt_gp->tg_pt_gp_valid_id = 1;
1390         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1391                         &su_dev->t10_alua.tg_pt_gps_list);
1392         su_dev->t10_alua.alua_tg_pt_gps_count++;
1393         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1394
1395         return 0;
1396 }
1397
1398 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1399         struct se_port *port)
1400 {
1401         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1402
1403         tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1404                                 GFP_KERNEL);
1405         if (!tg_pt_gp_mem) {
1406                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1407                 return ERR_PTR(-ENOMEM);
1408         }
1409         INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1410         spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1411         atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1412
1413         tg_pt_gp_mem->tg_pt = port;
1414         port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1415         atomic_set(&port->sep_tg_pt_gp_active, 1);
1416
1417         return tg_pt_gp_mem;
1418 }
1419
1420 void core_alua_free_tg_pt_gp(
1421         struct t10_alua_tg_pt_gp *tg_pt_gp)
1422 {
1423         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1424         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1425         /*
1426          * Once we have reached this point, config_item_put() has already
1427          * been called from target_core_alua_drop_tg_pt_gp().
1428          *
1429          * Here we remove *tg_pt_gp from the global list so that
1430          * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
1431          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1432          */
1433         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1434         list_del(&tg_pt_gp->tg_pt_gp_list);
1435         su_dev->t10_alua.alua_tg_pt_gps_counter--;
1436         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1437         /*
1438          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1439          * core_alua_get_tg_pt_gp_by_name() in
1440          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1441          * to be released with core_alua_put_tg_pt_gp_from_name().
1442          */
1443         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1444                 cpu_relax();
1445         /*
1446          * Release reference to struct t10_alua_tg_pt_gp from all associated
1447          * struct se_port.
1448          */
1449         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1450         list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1451                         &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1452                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1453                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1454                         tg_pt_gp->tg_pt_gp_members--;
1455                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1456                 }
1457                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1458                 /*
1459                  * tg_pt_gp_mem is associated with a single
1460                  * se_port->sep_alua_tg_pt_gp_mem, and is released via
1461                  * core_alua_free_tg_pt_gp_mem().
1462                  *
1463                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1464                  * assume we want to re-assocate a given tg_pt_gp_mem with
1465                  * default_tg_pt_gp.
1466                  */
1467                 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1468                 if (tg_pt_gp != su_dev->t10_alua.default_tg_pt_gp) {
1469                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1470                                         su_dev->t10_alua.default_tg_pt_gp);
1471                 } else
1472                         tg_pt_gp_mem->tg_pt_gp = NULL;
1473                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1474
1475                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1476         }
1477         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1478
1479         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1480 }
1481
1482 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1483 {
1484         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1485         struct t10_alua *alua = &su_dev->t10_alua;
1486         struct t10_alua_tg_pt_gp *tg_pt_gp;
1487         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1488
1489         if (alua->alua_type != SPC3_ALUA_EMULATED)
1490                 return;
1491
1492         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1493         if (!tg_pt_gp_mem)
1494                 return;
1495
1496         while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1497                 cpu_relax();
1498
1499         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1500         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1501         if (tg_pt_gp) {
1502                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1503                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1504                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1505                         tg_pt_gp->tg_pt_gp_members--;
1506                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1507                 }
1508                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1509                 tg_pt_gp_mem->tg_pt_gp = NULL;
1510         }
1511         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1512
1513         kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1514 }
1515
1516 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1517         struct se_subsystem_dev *su_dev,
1518         const char *name)
1519 {
1520         struct t10_alua_tg_pt_gp *tg_pt_gp;
1521         struct config_item *ci;
1522
1523         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1524         list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
1525                         tg_pt_gp_list) {
1526                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1527                         continue;
1528                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1529                 if (!strcmp(config_item_name(ci), name)) {
1530                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1531                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1532                         return tg_pt_gp;
1533                 }
1534         }
1535         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1536
1537         return NULL;
1538 }
1539
1540 static void core_alua_put_tg_pt_gp_from_name(
1541         struct t10_alua_tg_pt_gp *tg_pt_gp)
1542 {
1543         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1544
1545         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1546         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1547         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1548 }
1549
1550 /*
1551  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1552  */
1553 void __core_alua_attach_tg_pt_gp_mem(
1554         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1555         struct t10_alua_tg_pt_gp *tg_pt_gp)
1556 {
1557         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1558         tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1559         tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1560         list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1561                         &tg_pt_gp->tg_pt_gp_mem_list);
1562         tg_pt_gp->tg_pt_gp_members++;
1563         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1564 }
1565
1566 /*
1567  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1568  */
1569 static void __core_alua_drop_tg_pt_gp_mem(
1570         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1571         struct t10_alua_tg_pt_gp *tg_pt_gp)
1572 {
1573         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1574         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1575         tg_pt_gp_mem->tg_pt_gp = NULL;
1576         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1577         tg_pt_gp->tg_pt_gp_members--;
1578         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1579 }
1580
1581 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1582 {
1583         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1584         struct config_item *tg_pt_ci;
1585         struct t10_alua *alua = &su_dev->t10_alua;
1586         struct t10_alua_tg_pt_gp *tg_pt_gp;
1587         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1588         ssize_t len = 0;
1589
1590         if (alua->alua_type != SPC3_ALUA_EMULATED)
1591                 return len;
1592
1593         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1594         if (!tg_pt_gp_mem)
1595                 return len;
1596
1597         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1598         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1599         if (tg_pt_gp) {
1600                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1601                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1602                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1603                         "Primary Access Status: %s\nTG Port Secondary Access"
1604                         " State: %s\nTG Port Secondary Access Status: %s\n",
1605                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1606                         core_alua_dump_state(atomic_read(
1607                                         &tg_pt_gp->tg_pt_gp_alua_access_state)),
1608                         core_alua_dump_status(
1609                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1610                         (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
1611                         "Offline" : "None",
1612                         core_alua_dump_status(port->sep_tg_pt_secondary_stat));
1613         }
1614         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1615
1616         return len;
1617 }
1618
1619 ssize_t core_alua_store_tg_pt_gp_info(
1620         struct se_port *port,
1621         const char *page,
1622         size_t count)
1623 {
1624         struct se_portal_group *tpg;
1625         struct se_lun *lun;
1626         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1627         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1628         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1629         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1630         int move = 0;
1631
1632         tpg = port->sep_tpg;
1633         lun = port->sep_lun;
1634
1635         if (su_dev->t10_alua.alua_type != SPC3_ALUA_EMULATED) {
1636                 pr_warn("SPC3_ALUA_EMULATED not enabled for"
1637                         " %s/tpgt_%hu/%s\n", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1638                         tpg->se_tpg_tfo->tpg_get_tag(tpg),
1639                         config_item_name(&lun->lun_group.cg_item));
1640                 return -EINVAL;
1641         }
1642
1643         if (count > TG_PT_GROUP_NAME_BUF) {
1644                 pr_err("ALUA Target Port Group alias too large!\n");
1645                 return -EINVAL;
1646         }
1647         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1648         memcpy(buf, page, count);
1649         /*
1650          * Any ALUA target port group alias besides "NULL" means we will be
1651          * making a new group association.
1652          */
1653         if (strcmp(strstrip(buf), "NULL")) {
1654                 /*
1655                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1656                  * struct t10_alua_tg_pt_gp.  This reference is released with
1657                  * core_alua_put_tg_pt_gp_from_name() below.
1658                  */
1659                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
1660                                         strstrip(buf));
1661                 if (!tg_pt_gp_new)
1662                         return -ENODEV;
1663         }
1664         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1665         if (!tg_pt_gp_mem) {
1666                 if (tg_pt_gp_new)
1667                         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1668                 pr_err("NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
1669                 return -EINVAL;
1670         }
1671
1672         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1673         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1674         if (tg_pt_gp) {
1675                 /*
1676                  * Clearing an existing tg_pt_gp association, and replacing
1677                  * with the default_tg_pt_gp.
1678                  */
1679                 if (!tg_pt_gp_new) {
1680                         pr_debug("Target_Core_ConfigFS: Moving"
1681                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1682                                 " alua/%s, ID: %hu back to"
1683                                 " default_tg_pt_gp\n",
1684                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1685                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1686                                 config_item_name(&lun->lun_group.cg_item),
1687                                 config_item_name(
1688                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1689                                 tg_pt_gp->tg_pt_gp_id);
1690
1691                         __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1692                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1693                                         su_dev->t10_alua.default_tg_pt_gp);
1694                         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1695
1696                         return count;
1697                 }
1698                 /*
1699                  * Removing existing association of tg_pt_gp_mem with tg_pt_gp
1700                  */
1701                 __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1702                 move = 1;
1703         }
1704         /*
1705          * Associate tg_pt_gp_mem with tg_pt_gp_new.
1706          */
1707         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
1708         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1709         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1710                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1711                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1712                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1713                 config_item_name(&lun->lun_group.cg_item),
1714                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1715                 tg_pt_gp_new->tg_pt_gp_id);
1716
1717         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1718         return count;
1719 }
1720
1721 ssize_t core_alua_show_access_type(
1722         struct t10_alua_tg_pt_gp *tg_pt_gp,
1723         char *page)
1724 {
1725         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
1726             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
1727                 return sprintf(page, "Implict and Explict\n");
1728         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
1729                 return sprintf(page, "Implict\n");
1730         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
1731                 return sprintf(page, "Explict\n");
1732         else
1733                 return sprintf(page, "None\n");
1734 }
1735
1736 ssize_t core_alua_store_access_type(
1737         struct t10_alua_tg_pt_gp *tg_pt_gp,
1738         const char *page,
1739         size_t count)
1740 {
1741         unsigned long tmp;
1742         int ret;
1743
1744         ret = strict_strtoul(page, 0, &tmp);
1745         if (ret < 0) {
1746                 pr_err("Unable to extract alua_access_type\n");
1747                 return -EINVAL;
1748         }
1749         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
1750                 pr_err("Illegal value for alua_access_type:"
1751                                 " %lu\n", tmp);
1752                 return -EINVAL;
1753         }
1754         if (tmp == 3)
1755                 tg_pt_gp->tg_pt_gp_alua_access_type =
1756                         TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
1757         else if (tmp == 2)
1758                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
1759         else if (tmp == 1)
1760                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
1761         else
1762                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
1763
1764         return count;
1765 }
1766
1767 ssize_t core_alua_show_nonop_delay_msecs(
1768         struct t10_alua_tg_pt_gp *tg_pt_gp,
1769         char *page)
1770 {
1771         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
1772 }
1773
1774 ssize_t core_alua_store_nonop_delay_msecs(
1775         struct t10_alua_tg_pt_gp *tg_pt_gp,
1776         const char *page,
1777         size_t count)
1778 {
1779         unsigned long tmp;
1780         int ret;
1781
1782         ret = strict_strtoul(page, 0, &tmp);
1783         if (ret < 0) {
1784                 pr_err("Unable to extract nonop_delay_msecs\n");
1785                 return -EINVAL;
1786         }
1787         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
1788                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
1789                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
1790                         ALUA_MAX_NONOP_DELAY_MSECS);
1791                 return -EINVAL;
1792         }
1793         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
1794
1795         return count;
1796 }
1797
1798 ssize_t core_alua_show_trans_delay_msecs(
1799         struct t10_alua_tg_pt_gp *tg_pt_gp,
1800         char *page)
1801 {
1802         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1803 }
1804
1805 ssize_t core_alua_store_trans_delay_msecs(
1806         struct t10_alua_tg_pt_gp *tg_pt_gp,
1807         const char *page,
1808         size_t count)
1809 {
1810         unsigned long tmp;
1811         int ret;
1812
1813         ret = strict_strtoul(page, 0, &tmp);
1814         if (ret < 0) {
1815                 pr_err("Unable to extract trans_delay_msecs\n");
1816                 return -EINVAL;
1817         }
1818         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
1819                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
1820                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
1821                         ALUA_MAX_TRANS_DELAY_MSECS);
1822                 return -EINVAL;
1823         }
1824         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
1825
1826         return count;
1827 }
1828
1829 ssize_t core_alua_show_preferred_bit(
1830         struct t10_alua_tg_pt_gp *tg_pt_gp,
1831         char *page)
1832 {
1833         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
1834 }
1835
1836 ssize_t core_alua_store_preferred_bit(
1837         struct t10_alua_tg_pt_gp *tg_pt_gp,
1838         const char *page,
1839         size_t count)
1840 {
1841         unsigned long tmp;
1842         int ret;
1843
1844         ret = strict_strtoul(page, 0, &tmp);
1845         if (ret < 0) {
1846                 pr_err("Unable to extract preferred ALUA value\n");
1847                 return -EINVAL;
1848         }
1849         if ((tmp != 0) && (tmp != 1)) {
1850                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
1851                 return -EINVAL;
1852         }
1853         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
1854
1855         return count;
1856 }
1857
1858 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
1859 {
1860         if (!lun->lun_sep)
1861                 return -ENODEV;
1862
1863         return sprintf(page, "%d\n",
1864                 atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
1865 }
1866
1867 ssize_t core_alua_store_offline_bit(
1868         struct se_lun *lun,
1869         const char *page,
1870         size_t count)
1871 {
1872         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1873         unsigned long tmp;
1874         int ret;
1875
1876         if (!lun->lun_sep)
1877                 return -ENODEV;
1878
1879         ret = strict_strtoul(page, 0, &tmp);
1880         if (ret < 0) {
1881                 pr_err("Unable to extract alua_tg_pt_offline value\n");
1882                 return -EINVAL;
1883         }
1884         if ((tmp != 0) && (tmp != 1)) {
1885                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
1886                                 tmp);
1887                 return -EINVAL;
1888         }
1889         tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
1890         if (!tg_pt_gp_mem) {
1891                 pr_err("Unable to locate *tg_pt_gp_mem\n");
1892                 return -EINVAL;
1893         }
1894
1895         ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
1896                         lun->lun_sep, 0, (int)tmp);
1897         if (ret < 0)
1898                 return -EINVAL;
1899
1900         return count;
1901 }
1902
1903 ssize_t core_alua_show_secondary_status(
1904         struct se_lun *lun,
1905         char *page)
1906 {
1907         return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
1908 }
1909
1910 ssize_t core_alua_store_secondary_status(
1911         struct se_lun *lun,
1912         const char *page,
1913         size_t count)
1914 {
1915         unsigned long tmp;
1916         int ret;
1917
1918         ret = strict_strtoul(page, 0, &tmp);
1919         if (ret < 0) {
1920                 pr_err("Unable to extract alua_tg_pt_status\n");
1921                 return -EINVAL;
1922         }
1923         if ((tmp != ALUA_STATUS_NONE) &&
1924             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
1925             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
1926                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
1927                                 tmp);
1928                 return -EINVAL;
1929         }
1930         lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
1931
1932         return count;
1933 }
1934
1935 ssize_t core_alua_show_secondary_write_metadata(
1936         struct se_lun *lun,
1937         char *page)
1938 {
1939         return sprintf(page, "%d\n",
1940                         lun->lun_sep->sep_tg_pt_secondary_write_md);
1941 }
1942
1943 ssize_t core_alua_store_secondary_write_metadata(
1944         struct se_lun *lun,
1945         const char *page,
1946         size_t count)
1947 {
1948         unsigned long tmp;
1949         int ret;
1950
1951         ret = strict_strtoul(page, 0, &tmp);
1952         if (ret < 0) {
1953                 pr_err("Unable to extract alua_tg_pt_write_md\n");
1954                 return -EINVAL;
1955         }
1956         if ((tmp != 0) && (tmp != 1)) {
1957                 pr_err("Illegal value for alua_tg_pt_write_md:"
1958                                 " %lu\n", tmp);
1959                 return -EINVAL;
1960         }
1961         lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
1962
1963         return count;
1964 }
1965
1966 int core_setup_alua(struct se_device *dev, int force_pt)
1967 {
1968         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1969         struct t10_alua *alua = &su_dev->t10_alua;
1970         struct t10_alua_lu_gp_member *lu_gp_mem;
1971         /*
1972          * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
1973          * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
1974          * cause a problem because libata and some SATA RAID HBAs appear
1975          * under Linux/SCSI, but emulate SCSI logic themselves.
1976          */
1977         if (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
1978             !(dev->se_sub_dev->se_dev_attrib.emulate_alua)) || force_pt) {
1979                 alua->alua_type = SPC_ALUA_PASSTHROUGH;
1980                 alua->alua_state_check = &core_alua_state_check_nop;
1981                 pr_debug("%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
1982                         " emulation\n", dev->transport->name);
1983                 return 0;
1984         }
1985         /*
1986          * If SPC-3 or above is reported by real or emulated struct se_device,
1987          * use emulated ALUA.
1988          */
1989         if (dev->transport->get_device_rev(dev) >= SCSI_3) {
1990                 pr_debug("%s: Enabling ALUA Emulation for SPC-3"
1991                         " device\n", dev->transport->name);
1992                 /*
1993                  * Associate this struct se_device with the default ALUA
1994                  * LUN Group.
1995                  */
1996                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
1997                 if (IS_ERR(lu_gp_mem))
1998                         return PTR_ERR(lu_gp_mem);
1999
2000                 alua->alua_type = SPC3_ALUA_EMULATED;
2001                 alua->alua_state_check = &core_alua_state_check;
2002                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2003                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2004                                 default_lu_gp);
2005                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2006
2007                 pr_debug("%s: Adding to default ALUA LU Group:"
2008                         " core/alua/lu_gps/default_lu_gp\n",
2009                         dev->transport->name);
2010         } else {
2011                 alua->alua_type = SPC2_ALUA_DISABLED;
2012                 alua->alua_state_check = &core_alua_state_check_nop;
2013                 pr_debug("%s: Disabling ALUA Emulation for SPC-2"
2014                         " device\n", dev->transport->name);
2015         }
2016
2017         return 0;
2018 }