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/version.h>
  28 #include <linux/slab.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/configfs.h>
  31 #include <scsi/scsi.h>
  32 #include <scsi/scsi_cmnd.h>
  33
  34 #include <target/target_core_base.h>
  35 #include <target/target_core_device.h>
  36 #include <target/target_core_transport.h>
  37 #include <target/target_core_fabric_ops.h>
  38 #include <target/target_core_configfs.h>
  39
  40 #include "target_core_alua.h"
  41 #include "target_core_hba.h"
  42 #include "target_core_ua.h"
  43
  44 static int core_alua_check_transition(int state, int *primary);
  45 static int core_alua_set_tg_pt_secondary_state(
  46                 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
  47                 struct se_port *port, int explict, int offline);
  48
  49 static u16 alua_lu_gps_counter;
  50 static u32 alua_lu_gps_count;
  51
  52 static DEFINE_SPINLOCK(lu_gps_lock);
  53 static LIST_HEAD(lu_gps_list);
  54
  55 struct t10_alua_lu_gp *default_lu_gp;
  56
  57 /*
  58  * REPORT_TARGET_PORT_GROUPS
  59  *
  60  * See spc4r17 section 6.27
  61  */
  62 int core_emulate_report_target_port_groups(struct se_cmd *cmd)
  63 {
  64         struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
  65         struct se_port *port;
  66         struct t10_alua_tg_pt_gp *tg_pt_gp;
  67         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
  68         unsigned char *buf;
  69         u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
  70                                     Target port group descriptor */
  71
  72         buf = transport_kmap_first_data_page(cmd);
  73
  74         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
  75         list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
  76                         tg_pt_gp_list) {
  77                 /*
  78                  * PREF: Preferred target port bit, determine if this
  79                  * bit should be set for port group.
  80                  */
  81                 if (tg_pt_gp->tg_pt_gp_pref)
  82                         buf[off] = 0x80;
  83                 /*
  84                  * Set the ASYMMETRIC ACCESS State
  85                  */
  86                 buf[off++] |= (atomic_read(
  87                         &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
  88                 /*
  89                  * Set supported ASYMMETRIC ACCESS State bits
  90                  */
  91                 buf[off] = 0x80; /* T_SUP */
  92                 buf[off] |= 0x40; /* O_SUP */
  93                 buf[off] |= 0x8; /* U_SUP */
  94                 buf[off] |= 0x4; /* S_SUP */
  95                 buf[off] |= 0x2; /* AN_SUP */
  96                 buf[off++] |= 0x1; /* AO_SUP */
  97                 /*
  98                  * TARGET PORT GROUP
  99                  */
 100                 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
 101                 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
 102
 103                 off++; /* Skip over Reserved */
 104                 /*
 105                  * STATUS CODE
 106                  */
 107                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
 108                 /*
 109                  * Vendor Specific field
 110                  */
 111                 buf[off++] = 0x00;
 112                 /*
 113                  * TARGET PORT COUNT
 114                  */
 115                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 116                 rd_len += 8;
 117
 118                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 119                 list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
 120                                 tg_pt_gp_mem_list) {
 121                         port = tg_pt_gp_mem->tg_pt;
 122                         /*
 123                          * Start Target Port descriptor format
 124                          *
 125                          * See spc4r17 section 6.2.7 Table 247
 126                          */
 127                         off += 2; /* Skip over Obsolete */
 128                         /*
 129                          * Set RELATIVE TARGET PORT IDENTIFIER
 130                          */
 131                         buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
 132                         buf[off++] = (port->sep_rtpi & 0xff);
 133                         rd_len += 4;
 134                 }
 135                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 136         }
 137         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 138         /*
 139          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 140          */
 141         buf[0] = ((rd_len >> 24) & 0xff);
 142         buf[1] = ((rd_len >> 16) & 0xff);
 143         buf[2] = ((rd_len >> 8) & 0xff);
 144         buf[3] = (rd_len & 0xff);
 145
 146         transport_kunmap_first_data_page(cmd);
 147
 148         return 0;
 149 }
 150
 151 /*
 152  * SET_TARGET_PORT_GROUPS for explict ALUA operation.
 153  *
 154  * See spc4r17 section 6.35
 155  */
 156 int core_emulate_set_target_port_groups(struct se_cmd *cmd)
 157 {
 158         struct se_device *dev = cmd->se_dev;
 159         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
 160         struct se_port *port, *l_port = cmd->se_lun->lun_sep;
 161         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
 162         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 163         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
 164         unsigned char *buf;
 165         unsigned char *ptr;
 166         u32 len = 4; /* Skip over RESERVED area in header */
 167         int alua_access_state, primary = 0, rc;
 168         u16 tg_pt_id, rtpi;
 169
 170         if (!l_port)
 171                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 172
 173         buf = transport_kmap_first_data_page(cmd);
 174
 175         /*
 176          * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
 177          * for the local tg_pt_gp.
 178          */
 179         l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
 180         if (!l_tg_pt_gp_mem) {
 181                 pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
 182                 rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 183                 goto out;
 184         }
 185         spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 186         l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
 187         if (!l_tg_pt_gp) {
 188                 spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 189                 pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
 190                 rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 191                 goto out;
 192         }
 193         rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
 194         spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 195
 196         if (!rc) {
 197                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
 198                                 " while TPGS_EXPLICT_ALUA is disabled\n");
 199                 rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 200                 goto out;
 201         }
 202
 203         ptr = &buf[4]; /* Skip over RESERVED area in header */
 204
 205         while (len < cmd->data_length) {
 206                 alua_access_state = (ptr[0] & 0x0f);
 207                 /*
 208                  * Check the received ALUA access state, and determine if
 209                  * the state is a primary or secondary target port asymmetric
 210                  * access state.
 211                  */
 212                 rc = core_alua_check_transition(alua_access_state, &primary);
 213                 if (rc != 0) {
 214                         /*
 215                          * If the SET TARGET PORT GROUPS attempts to establish
 216                          * an invalid combination of target port asymmetric
 217                          * access states or attempts to establish an
 218                          * unsupported target port asymmetric access state,
 219                          * then the command shall be terminated with CHECK
 220                          * CONDITION status, with the sense key set to ILLEGAL
 221                          * REQUEST, and the additional sense code set to INVALID
 222                          * FIELD IN PARAMETER LIST.
 223                          */
 224                         rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 225                         goto out;
 226                 }
 227                 rc = -1;
 228                 /*
 229                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 230                  * specifies a primary target port asymmetric access state,
 231                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 232                  * a primary target port group for which the primary target
 233                  * port asymmetric access state shall be changed. If the
 234                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 235                  * port asymmetric access state, then the TARGET PORT GROUP OR
 236                  * TARGET PORT field specifies the relative target port
 237                  * identifier (see 3.1.120) of the target port for which the
 238                  * secondary target port asymmetric access state shall be
 239                  * changed.
 240                  */
 241                 if (primary) {
 242                         tg_pt_id = ((ptr[2] << 8) & 0xff);
 243                         tg_pt_id |= (ptr[3] & 0xff);
 244                         /*
 245                          * Locate the matching target port group ID from
 246                          * the global tg_pt_gp list
 247                          */
 248                         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 249                         list_for_each_entry(tg_pt_gp,
 250                                         &su_dev->t10_alua.tg_pt_gps_list,
 251                                         tg_pt_gp_list) {
 252                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
 253                                         continue;
 254
 255                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 256                                         continue;
 257
 258                                 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 259                                 smp_mb__after_atomic_inc();
 260                                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 261
 262                                 rc = core_alua_do_port_transition(tg_pt_gp,
 263                                                 dev, l_port, nacl,
 264                                                 alua_access_state, 1);
 265
 266                                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 267                                 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 268                                 smp_mb__after_atomic_dec();
 269                                 break;
 270                         }
 271                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 272                         /*
 273                          * If not matching target port group ID can be located
 274                          * throw an exception with ASCQ: INVALID_PARAMETER_LIST
 275                          */
 276                         if (rc != 0) {
 277                                 rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 278                                 goto out;
 279                         }
 280                 } else {
 281                         /*
 282                          * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
 283                          * the Target Port in question for the the incoming
 284                          * SET_TARGET_PORT_GROUPS op.
 285                          */
 286                         rtpi = ((ptr[2] << 8) & 0xff);
 287                         rtpi |= (ptr[3] & 0xff);
 288                         /*
 289                          * Locate the matching relative target port identifer
 290                          * for the struct se_device storage object.
 291                          */
 292                         spin_lock(&dev->se_port_lock);
 293                         list_for_each_entry(port, &dev->dev_sep_list,
 294                                                         sep_list) {
 295                                 if (port->sep_rtpi != rtpi)
 296                                         continue;
 297
 298                                 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 299                                 spin_unlock(&dev->se_port_lock);
 300
 301                                 rc = core_alua_set_tg_pt_secondary_state(
 302                                                 tg_pt_gp_mem, port, 1, 1);
 303
 304                                 spin_lock(&dev->se_port_lock);
 305                                 break;
 306                         }
 307                         spin_unlock(&dev->se_port_lock);
 308                         /*
 309                          * If not matching relative target port identifier can
 310                          * be located, throw an exception with ASCQ:
 311                          * INVALID_PARAMETER_LIST
 312                          */
 313                         if (rc != 0) {
 314                                 rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 315                                 goto out;
 316                         }
 317                 }
 318
 319                 ptr += 4;
 320                 len += 4;
 321         }
 322
 323 out:
 324         transport_kunmap_first_data_page(cmd);
 325
 326         return 0;
 327 }
 328
 329 static inline int core_alua_state_nonoptimized(
 330         struct se_cmd *cmd,
 331         unsigned char *cdb,
 332         int nonop_delay_msecs,
 333         u8 *alua_ascq)
 334 {
 335         /*
 336          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 337          * later to determine if processing of this cmd needs to be
 338          * temporarily delayed for the Active/NonOptimized primary access state.
 339          */
 340         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 341         cmd->alua_nonop_delay = nonop_delay_msecs;
 342         return 0;
 343 }
 344
 345 static inline int core_alua_state_standby(
 346         struct se_cmd *cmd,
 347         unsigned char *cdb,
 348         u8 *alua_ascq)
 349 {
 350         /*
 351          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 352          * spc4r17 section 5.9.2.4.4
 353          */
 354         switch (cdb[0]) {
 355         case INQUIRY:
 356         case LOG_SELECT:
 357         case LOG_SENSE:
 358         case MODE_SELECT:
 359         case MODE_SENSE:
 360         case REPORT_LUNS:
 361         case RECEIVE_DIAGNOSTIC:
 362         case SEND_DIAGNOSTIC:
 363         case MAINTENANCE_IN:
 364                 switch (cdb[1]) {
 365                 case MI_REPORT_TARGET_PGS:
 366                         return 0;
 367                 default:
 368                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 369                         return 1;
 370                 }
 371         case MAINTENANCE_OUT:
 372                 switch (cdb[1]) {
 373                 case MO_SET_TARGET_PGS:
 374                         return 0;
 375                 default:
 376                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 377                         return 1;
 378                 }
 379         case REQUEST_SENSE:
 380         case PERSISTENT_RESERVE_IN:
 381         case PERSISTENT_RESERVE_OUT:
 382         case READ_BUFFER:
 383         case WRITE_BUFFER:
 384                 return 0;
 385         default:
 386                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 387                 return 1;
 388         }
 389
 390         return 0;
 391 }
 392
 393 static inline int core_alua_state_unavailable(
 394         struct se_cmd *cmd,
 395         unsigned char *cdb,
 396         u8 *alua_ascq)
 397 {
 398         /*
 399          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 400          * spc4r17 section 5.9.2.4.5
 401          */
 402         switch (cdb[0]) {
 403         case INQUIRY:
 404         case REPORT_LUNS:
 405         case MAINTENANCE_IN:
 406                 switch (cdb[1]) {
 407                 case MI_REPORT_TARGET_PGS:
 408                         return 0;
 409                 default:
 410                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 411                         return 1;
 412                 }
 413         case MAINTENANCE_OUT:
 414                 switch (cdb[1]) {
 415                 case MO_SET_TARGET_PGS:
 416                         return 0;
 417                 default:
 418                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 419                         return 1;
 420                 }
 421         case REQUEST_SENSE:
 422         case READ_BUFFER:
 423         case WRITE_BUFFER:
 424                 return 0;
 425         default:
 426                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 427                 return 1;
 428         }
 429
 430         return 0;
 431 }
 432
 433 static inline int core_alua_state_transition(
 434         struct se_cmd *cmd,
 435         unsigned char *cdb,
 436         u8 *alua_ascq)
 437 {
 438         /*
 439          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
 440          * spc4r17 section 5.9.2.5
 441          */
 442         switch (cdb[0]) {
 443         case INQUIRY:
 444         case REPORT_LUNS:
 445         case MAINTENANCE_IN:
 446                 switch (cdb[1]) {
 447                 case MI_REPORT_TARGET_PGS:
 448                         return 0;
 449                 default:
 450                         *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 451                         return 1;
 452                 }
 453         case REQUEST_SENSE:
 454         case READ_BUFFER:
 455         case WRITE_BUFFER:
 456                 return 0;
 457         default:
 458                 *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 459                 return 1;
 460         }
 461
 462         return 0;
 463 }
 464
 465 /*
 466  * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
 467  * in transport_cmd_sequencer().  This function is assigned to
 468  * struct t10_alua *->state_check() in core_setup_alua()
 469  */
 470 static int core_alua_state_check_nop(
 471         struct se_cmd *cmd,
 472         unsigned char *cdb,
 473         u8 *alua_ascq)
 474 {
 475         return 0;
 476 }
 477
 478 /*
 479  * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
 480  * This function is assigned to struct t10_alua *->state_check() in
 481  * core_setup_alua()
 482  *
 483  * Also, this function can return three different return codes to
 484  * signal transport_generic_cmd_sequencer()
 485  *
 486  * return 1: Is used to signal LUN not accecsable, and check condition/not ready
 487  * return 0: Used to signal success
 488  * reutrn -1: Used to signal failure, and invalid cdb field
 489  */
 490 static int core_alua_state_check(
 491         struct se_cmd *cmd,
 492         unsigned char *cdb,
 493         u8 *alua_ascq)
 494 {
 495         struct se_lun *lun = cmd->se_lun;
 496         struct se_port *port = lun->lun_sep;
 497         struct t10_alua_tg_pt_gp *tg_pt_gp;
 498         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
 499         int out_alua_state, nonop_delay_msecs;
 500
 501         if (!port)
 502                 return 0;
 503         /*
 504          * First, check for a struct se_port specific secondary ALUA target port
 505          * access state: OFFLINE
 506          */
 507         if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
 508                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 509                 pr_debug("ALUA: Got secondary offline status for local"
 510                                 " target port\n");
 511                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 512                 return 1;
 513         }
 514          /*
 515          * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
 516          * ALUA target port group, to obtain current ALUA access state.
 517          * Otherwise look for the underlying struct se_device association with
 518          * a ALUA logical unit group.
 519          */
 520         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 521         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 522         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
 523         out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 524         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 525         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 526         /*
 527          * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a separate conditional
 528          * statement so the compiler knows explicitly to check this case first.
 529          * For the Optimized ALUA access state case, we want to process the
 530          * incoming fabric cmd ASAP..
 531          */
 532         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
 533                 return 0;
 534
 535         switch (out_alua_state) {
 536         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 537                 return core_alua_state_nonoptimized(cmd, cdb,
 538                                         nonop_delay_msecs, alua_ascq);
 539         case ALUA_ACCESS_STATE_STANDBY:
 540                 return core_alua_state_standby(cmd, cdb, alua_ascq);
 541         case ALUA_ACCESS_STATE_UNAVAILABLE:
 542                 return core_alua_state_unavailable(cmd, cdb, alua_ascq);
 543         case ALUA_ACCESS_STATE_TRANSITION:
 544                 return core_alua_state_transition(cmd, cdb, alua_ascq);
 545         /*
 546          * OFFLINE is a secondary ALUA target port group access state, that is
 547          * handled above with struct se_port->sep_tg_pt_secondary_offline=1
 548          */
 549         case ALUA_ACCESS_STATE_OFFLINE:
 550         default:
 551                 pr_err("Unknown ALUA access state: 0x%02x\n",
 552                                 out_alua_state);
 553                 return -EINVAL;
 554         }
 555
 556         return 0;
 557 }
 558
 559 /*
 560  * Check implict and explict ALUA state change request.
 561  */
 562 static int core_alua_check_transition(int state, int *primary)
 563 {
 564         switch (state) {
 565         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 566         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 567         case ALUA_ACCESS_STATE_STANDBY:
 568         case ALUA_ACCESS_STATE_UNAVAILABLE:
 569                 /*
 570                  * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 571                  * defined as primary target port asymmetric access states.
 572                  */
 573                 *primary = 1;
 574                 break;
 575         case ALUA_ACCESS_STATE_OFFLINE:
 576                 /*
 577                  * OFFLINE state is defined as a secondary target port
 578                  * asymmetric access state.
 579                  */
 580                 *primary = 0;
 581                 break;
 582         default:
 583                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
 584                 return -EINVAL;
 585         }
 586
 587         return 0;
 588 }
 589
 590 static char *core_alua_dump_state(int state)
 591 {
 592         switch (state) {
 593         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 594                 return "Active/Optimized";
 595         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 596                 return "Active/NonOptimized";
 597         case ALUA_ACCESS_STATE_STANDBY:
 598                 return "Standby";
 599         case ALUA_ACCESS_STATE_UNAVAILABLE:
 600                 return "Unavailable";
 601         case ALUA_ACCESS_STATE_OFFLINE:
 602                 return "Offline";
 603         default:
 604                 return "Unknown";
 605         }
 606
 607         return NULL;
 608 }
 609
 610 char *core_alua_dump_status(int status)
 611 {
 612         switch (status) {
 613         case ALUA_STATUS_NONE:
 614                 return "None";
 615         case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
 616                 return "Altered by Explict STPG";
 617         case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
 618                 return "Altered by Implict ALUA";
 619         default:
 620                 return "Unknown";
 621         }
 622
 623         return NULL;
 624 }
 625
 626 /*
 627  * Used by fabric modules to determine when we need to delay processing
 628  * for the Active/NonOptimized paths..
 629  */
 630 int core_alua_check_nonop_delay(
 631         struct se_cmd *cmd)
 632 {
 633         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 634                 return 0;
 635         if (in_interrupt())
 636                 return 0;
 637         /*
 638          * The ALUA Active/NonOptimized access state delay can be disabled
 639          * in via configfs with a value of zero
 640          */
 641         if (!cmd->alua_nonop_delay)
 642                 return 0;
 643         /*
 644          * struct se_cmd->alua_nonop_delay gets set by a target port group
 645          * defined interval in core_alua_state_nonoptimized()
 646          */
 647         msleep_interruptible(cmd->alua_nonop_delay);
 648         return 0;
 649 }
 650 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 651
 652 /*
 653  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
 654  *
 655  */
 656 static int core_alua_write_tpg_metadata(
 657         const char *path,
 658         unsigned char *md_buf,
 659         u32 md_buf_len)
 660 {
 661         mm_segment_t old_fs;
 662         struct file *file;
 663         struct iovec iov[1];
 664         int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
 665
 666         memset(iov, 0, sizeof(struct iovec));
 667
 668         file = filp_open(path, flags, 0600);
 669         if (IS_ERR(file) || !file || !file->f_dentry) {
 670                 pr_err("filp_open(%s) for ALUA metadata failed\n",
 671                         path);
 672                 return -ENODEV;
 673         }
 674
 675         iov[0].iov_base = &md_buf[0];
 676         iov[0].iov_len = md_buf_len;
 677
 678         old_fs = get_fs();
 679         set_fs(get_ds());
 680         ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
 681         set_fs(old_fs);
 682
 683         if (ret < 0) {
 684                 pr_err("Error writing ALUA metadata file: %s\n", path);
 685                 filp_close(file, NULL);
 686                 return -EIO;
 687         }
 688         filp_close(file, NULL);
 689
 690         return 0;
 691 }
 692
 693 /*
 694  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
 695  */
 696 static int core_alua_update_tpg_primary_metadata(
 697         struct t10_alua_tg_pt_gp *tg_pt_gp,
 698         int primary_state,
 699         unsigned char *md_buf)
 700 {
 701         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
 702         struct t10_wwn *wwn = &su_dev->t10_wwn;
 703         char path[ALUA_METADATA_PATH_LEN];
 704         int len;
 705
 706         memset(path, 0, ALUA_METADATA_PATH_LEN);
 707
 708         len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
 709                         "tg_pt_gp_id=%hu\n"
 710                         "alua_access_state=0x%02x\n"
 711                         "alua_access_status=0x%02x\n",
 712                         tg_pt_gp->tg_pt_gp_id, primary_state,
 713                         tg_pt_gp->tg_pt_gp_alua_access_status);
 714
 715         snprintf(path, ALUA_METADATA_PATH_LEN,
 716                 "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
 717                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 718
 719         return core_alua_write_tpg_metadata(path, md_buf, len);
 720 }
 721
 722 static int core_alua_do_transition_tg_pt(
 723         struct t10_alua_tg_pt_gp *tg_pt_gp,
 724         struct se_port *l_port,
 725         struct se_node_acl *nacl,
 726         unsigned char *md_buf,
 727         int new_state,
 728         int explict)
 729 {
 730         struct se_dev_entry *se_deve;
 731         struct se_lun_acl *lacl;
 732         struct se_port *port;
 733         struct t10_alua_tg_pt_gp_member *mem;
 734         int old_state = 0;
 735         /*
 736          * Save the old primary ALUA access state, and set the current state
 737          * to ALUA_ACCESS_STATE_TRANSITION.
 738          */
 739         old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 740         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
 741                         ALUA_ACCESS_STATE_TRANSITION);
 742         tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
 743                                 ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
 744                                 ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
 745         /*
 746          * Check for the optional ALUA primary state transition delay
 747          */
 748         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
 749                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
 750
 751         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 752         list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
 753                                 tg_pt_gp_mem_list) {
 754                 port = mem->tg_pt;
 755                 /*
 756                  * After an implicit target port asymmetric access state
 757                  * change, a device server shall establish a unit attention
 758                  * condition for the initiator port associated with every I_T
 759                  * nexus with the additional sense code set to ASYMMETRIC
 760                  * ACCESS STATE CHAGED.
 761                  *
 762                  * After an explicit target port asymmetric access state
 763                  * change, a device server shall establish a unit attention
 764                  * condition with the additional sense code set to ASYMMETRIC
 765                  * ACCESS STATE CHANGED for the initiator port associated with
 766                  * every I_T nexus other than the I_T nexus on which the SET
 767                  * TARGET PORT GROUPS command
 768                  */
 769                 atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
 770                 smp_mb__after_atomic_inc();
 771                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 772
 773                 spin_lock_bh(&port->sep_alua_lock);
 774                 list_for_each_entry(se_deve, &port->sep_alua_list,
 775                                         alua_port_list) {
 776                         lacl = se_deve->se_lun_acl;
 777                         /*
 778                          * se_deve->se_lun_acl pointer may be NULL for a
 779                          * entry created without explict Node+MappedLUN ACLs
 780                          */
 781                         if (!lacl)
 782                                 continue;
 783
 784                         if (explict &&
 785                            (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
 786                            (l_port != NULL) && (l_port == port))
 787                                 continue;
 788
 789                         core_scsi3_ua_allocate(lacl->se_lun_nacl,
 790                                 se_deve->mapped_lun, 0x2A,
 791                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
 792                 }
 793                 spin_unlock_bh(&port->sep_alua_lock);
 794
 795                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 796                 atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
 797                 smp_mb__after_atomic_dec();
 798         }
 799         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 800         /*
 801          * Update the ALUA metadata buf that has been allocated in
 802          * core_alua_do_port_transition(), this metadata will be written
 803          * to struct file.
 804          *
 805          * Note that there is the case where we do not want to update the
 806          * metadata when the saved metadata is being parsed in userspace
 807          * when setting the existing port access state and access status.
 808          *
 809          * Also note that the failure to write out the ALUA metadata to
 810          * struct file does NOT affect the actual ALUA transition.
 811          */
 812         if (tg_pt_gp->tg_pt_gp_write_metadata) {
 813                 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
 814                 core_alua_update_tpg_primary_metadata(tg_pt_gp,
 815                                         new_state, md_buf);
 816                 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
 817         }
 818         /*
 819          * Set the current primary ALUA access state to the requested new state
 820          */
 821         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
 822
 823         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
 824                 " from primary access state %s to %s\n", (explict) ? "explict" :
 825                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
 826                 tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
 827                 core_alua_dump_state(new_state));
 828
 829         return 0;
 830 }
 831
 832 int core_alua_do_port_transition(
 833         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
 834         struct se_device *l_dev,
 835         struct se_port *l_port,
 836         struct se_node_acl *l_nacl,
 837         int new_state,
 838         int explict)
 839 {
 840         struct se_device *dev;
 841         struct se_port *port;
 842         struct se_subsystem_dev *su_dev;
 843         struct se_node_acl *nacl;
 844         struct t10_alua_lu_gp *lu_gp;
 845         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
 846         struct t10_alua_tg_pt_gp *tg_pt_gp;
 847         unsigned char *md_buf;
 848         int primary;
 849
 850         if (core_alua_check_transition(new_state, &primary) != 0)
 851                 return -EINVAL;
 852
 853         md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
 854         if (!md_buf) {
 855                 pr_err("Unable to allocate buf for ALUA metadata\n");
 856                 return -ENOMEM;
 857         }
 858
 859         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
 860         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
 861         lu_gp = local_lu_gp_mem->lu_gp;
 862         atomic_inc(&lu_gp->lu_gp_ref_cnt);
 863         smp_mb__after_atomic_inc();
 864         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
 865         /*
 866          * For storage objects that are members of the 'default_lu_gp',
 867          * we only do transition on the passed *l_tp_pt_gp, and not
 868          * on all of the matching target port groups IDs in default_lu_gp.
 869          */
 870         if (!lu_gp->lu_gp_id) {
 871                 /*
 872                  * core_alua_do_transition_tg_pt() will always return
 873                  * success.
 874                  */
 875                 core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
 876                                         md_buf, new_state, explict);
 877                 atomic_dec(&lu_gp->lu_gp_ref_cnt);
 878                 smp_mb__after_atomic_dec();
 879                 kfree(md_buf);
 880                 return 0;
 881         }
 882         /*
 883          * For all other LU groups aside from 'default_lu_gp', walk all of
 884          * the associated storage objects looking for a matching target port
 885          * group ID from the local target port group.
 886          */
 887         spin_lock(&lu_gp->lu_gp_lock);
 888         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
 889                                 lu_gp_mem_list) {
 890
 891                 dev = lu_gp_mem->lu_gp_mem_dev;
 892                 su_dev = dev->se_sub_dev;
 893                 atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
 894                 smp_mb__after_atomic_inc();
 895                 spin_unlock(&lu_gp->lu_gp_lock);
 896
 897                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 898                 list_for_each_entry(tg_pt_gp,
 899                                 &su_dev->t10_alua.tg_pt_gps_list,
 900                                 tg_pt_gp_list) {
 901
 902                         if (!tg_pt_gp->tg_pt_gp_valid_id)
 903                                 continue;
 904                         /*
 905                          * If the target behavior port asymmetric access state
 906                          * is changed for any target port group accessiable via
 907                          * a logical unit within a LU group, the target port
 908                          * behavior group asymmetric access states for the same
 909                          * target port group accessible via other logical units
 910                          * in that LU group will also change.
 911                          */
 912                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
 913                                 continue;
 914
 915                         if (l_tg_pt_gp == tg_pt_gp) {
 916                                 port = l_port;
 917                                 nacl = l_nacl;
 918                         } else {
 919                                 port = NULL;
 920                                 nacl = NULL;
 921                         }
 922                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 923                         smp_mb__after_atomic_inc();
 924                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 925                         /*
 926                          * core_alua_do_transition_tg_pt() will always return
 927                          * success.
 928                          */
 929                         core_alua_do_transition_tg_pt(tg_pt_gp, port,
 930                                         nacl, md_buf, new_state, explict);
 931
 932                         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
 933                         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 934                         smp_mb__after_atomic_dec();
 935                 }
 936                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
 937
 938                 spin_lock(&lu_gp->lu_gp_lock);
 939                 atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
 940                 smp_mb__after_atomic_dec();
 941         }
 942         spin_unlock(&lu_gp->lu_gp_lock);
 943
 944         pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
 945                 " Group IDs: %hu %s transition to primary state: %s\n",
 946                 config_item_name(&lu_gp->lu_gp_group.cg_item),
 947                 l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
 948                 core_alua_dump_state(new_state));
 949
 950         atomic_dec(&lu_gp->lu_gp_ref_cnt);
 951         smp_mb__after_atomic_dec();
 952         kfree(md_buf);
 953         return 0;
 954 }
 955
 956 /*
 957  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
 958  */
 959 static int core_alua_update_tpg_secondary_metadata(
 960         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 961         struct se_port *port,
 962         unsigned char *md_buf,
 963         u32 md_buf_len)
 964 {
 965         struct se_portal_group *se_tpg = port->sep_tpg;
 966         char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
 967         int len;
 968
 969         memset(path, 0, ALUA_METADATA_PATH_LEN);
 970         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
 971
 972         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
 973                         se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
 974
 975         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
 976                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
 977                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
 978
 979         len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
 980                         "alua_tg_pt_status=0x%02x\n",
 981                         atomic_read(&port->sep_tg_pt_secondary_offline),
 982                         port->sep_tg_pt_secondary_stat);
 983
 984         snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
 985                         se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
 986                         port->sep_lun->unpacked_lun);
 987
 988         return core_alua_write_tpg_metadata(path, md_buf, len);
 989 }
 990
 991 static int core_alua_set_tg_pt_secondary_state(
 992         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 993         struct se_port *port,
 994         int explict,
 995         int offline)
 996 {
 997         struct t10_alua_tg_pt_gp *tg_pt_gp;
 998         unsigned char *md_buf;
 999         u32 md_buf_len;
1000         int trans_delay_msecs;
1001
1002         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1003         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1004         if (!tg_pt_gp) {
1005                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1006                 pr_err("Unable to complete secondary state"
1007                                 " transition\n");
1008                 return -EINVAL;
1009         }
1010         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1011         /*
1012          * Set the secondary ALUA target port access state to OFFLINE
1013          * or release the previously secondary state for struct se_port
1014          */
1015         if (offline)
1016                 atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1017         else
1018                 atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1019
1020         md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
1021         port->sep_tg_pt_secondary_stat = (explict) ?
1022                         ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
1023                         ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
1024
1025         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1026                 " to secondary access state: %s\n", (explict) ? "explict" :
1027                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1028                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1029
1030         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1031         /*
1032          * Do the optional transition delay after we set the secondary
1033          * ALUA access state.
1034          */
1035         if (trans_delay_msecs != 0)
1036                 msleep_interruptible(trans_delay_msecs);
1037         /*
1038          * See if we need to update the ALUA fabric port metadata for
1039          * secondary state and status
1040          */
1041         if (port->sep_tg_pt_secondary_write_md) {
1042                 md_buf = kzalloc(md_buf_len, GFP_KERNEL);
1043                 if (!md_buf) {
1044                         pr_err("Unable to allocate md_buf for"
1045                                 " secondary ALUA access metadata\n");
1046                         return -ENOMEM;
1047                 }
1048                 mutex_lock(&port->sep_tg_pt_md_mutex);
1049                 core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
1050                                 md_buf, md_buf_len);
1051                 mutex_unlock(&port->sep_tg_pt_md_mutex);
1052
1053                 kfree(md_buf);
1054         }
1055
1056         return 0;
1057 }
1058
1059 struct t10_alua_lu_gp *
1060 core_alua_allocate_lu_gp(const char *name, int def_group)
1061 {
1062         struct t10_alua_lu_gp *lu_gp;
1063
1064         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1065         if (!lu_gp) {
1066                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1067                 return ERR_PTR(-ENOMEM);
1068         }
1069         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1070         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1071         spin_lock_init(&lu_gp->lu_gp_lock);
1072         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1073
1074         if (def_group) {
1075                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1076                 lu_gp->lu_gp_valid_id = 1;
1077                 alua_lu_gps_count++;
1078         }
1079
1080         return lu_gp;
1081 }
1082
1083 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1084 {
1085         struct t10_alua_lu_gp *lu_gp_tmp;
1086         u16 lu_gp_id_tmp;
1087         /*
1088          * The lu_gp->lu_gp_id may only be set once..
1089          */
1090         if (lu_gp->lu_gp_valid_id) {
1091                 pr_warn("ALUA LU Group already has a valid ID,"
1092                         " ignoring request\n");
1093                 return -EINVAL;
1094         }
1095
1096         spin_lock(&lu_gps_lock);
1097         if (alua_lu_gps_count == 0x0000ffff) {
1098                 pr_err("Maximum ALUA alua_lu_gps_count:"
1099                                 " 0x0000ffff reached\n");
1100                 spin_unlock(&lu_gps_lock);
1101                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1102                 return -ENOSPC;
1103         }
1104 again:
1105         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1106                                 alua_lu_gps_counter++;
1107
1108         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1109                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1110                         if (!lu_gp_id)
1111                                 goto again;
1112
1113                         pr_warn("ALUA Logical Unit Group ID: %hu"
1114                                 " already exists, ignoring request\n",
1115                                 lu_gp_id);
1116                         spin_unlock(&lu_gps_lock);
1117                         return -EINVAL;
1118                 }
1119         }
1120
1121         lu_gp->lu_gp_id = lu_gp_id_tmp;
1122         lu_gp->lu_gp_valid_id = 1;
1123         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1124         alua_lu_gps_count++;
1125         spin_unlock(&lu_gps_lock);
1126
1127         return 0;
1128 }
1129
1130 static struct t10_alua_lu_gp_member *
1131 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1132 {
1133         struct t10_alua_lu_gp_member *lu_gp_mem;
1134
1135         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1136         if (!lu_gp_mem) {
1137                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1138                 return ERR_PTR(-ENOMEM);
1139         }
1140         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1141         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1142         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1143
1144         lu_gp_mem->lu_gp_mem_dev = dev;
1145         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1146
1147         return lu_gp_mem;
1148 }
1149
1150 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1151 {
1152         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1153         /*
1154          * Once we have reached this point, config_item_put() has
1155          * already been called from target_core_alua_drop_lu_gp().
1156          *
1157          * Here, we remove the *lu_gp from the global list so that
1158          * no associations can be made while we are releasing
1159          * struct t10_alua_lu_gp.
1160          */
1161         spin_lock(&lu_gps_lock);
1162         atomic_set(&lu_gp->lu_gp_shutdown, 1);
1163         list_del(&lu_gp->lu_gp_node);
1164         alua_lu_gps_count--;
1165         spin_unlock(&lu_gps_lock);
1166         /*
1167          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1168          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1169          * released with core_alua_put_lu_gp_from_name()
1170          */
1171         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1172                 cpu_relax();
1173         /*
1174          * Release reference to struct t10_alua_lu_gp * from all associated
1175          * struct se_device.
1176          */
1177         spin_lock(&lu_gp->lu_gp_lock);
1178         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1179                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1180                 if (lu_gp_mem->lu_gp_assoc) {
1181                         list_del(&lu_gp_mem->lu_gp_mem_list);
1182                         lu_gp->lu_gp_members--;
1183                         lu_gp_mem->lu_gp_assoc = 0;
1184                 }
1185                 spin_unlock(&lu_gp->lu_gp_lock);
1186                 /*
1187                  *
1188                  * lu_gp_mem is associated with a single
1189                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1190                  * struct se_device is released via core_alua_free_lu_gp_mem().
1191                  *
1192                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1193                  * we want to re-assocate a given lu_gp_mem with default_lu_gp.
1194                  */
1195                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1196                 if (lu_gp != default_lu_gp)
1197                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1198                                         default_lu_gp);
1199                 else
1200                         lu_gp_mem->lu_gp = NULL;
1201                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1202
1203                 spin_lock(&lu_gp->lu_gp_lock);
1204         }
1205         spin_unlock(&lu_gp->lu_gp_lock);
1206
1207         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1208 }
1209
1210 void core_alua_free_lu_gp_mem(struct se_device *dev)
1211 {
1212         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1213         struct t10_alua *alua = &su_dev->t10_alua;
1214         struct t10_alua_lu_gp *lu_gp;
1215         struct t10_alua_lu_gp_member *lu_gp_mem;
1216
1217         if (alua->alua_type != SPC3_ALUA_EMULATED)
1218                 return;
1219
1220         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1221         if (!lu_gp_mem)
1222                 return;
1223
1224         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1225                 cpu_relax();
1226
1227         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1228         lu_gp = lu_gp_mem->lu_gp;
1229         if (lu_gp) {
1230                 spin_lock(&lu_gp->lu_gp_lock);
1231                 if (lu_gp_mem->lu_gp_assoc) {
1232                         list_del(&lu_gp_mem->lu_gp_mem_list);
1233                         lu_gp->lu_gp_members--;
1234                         lu_gp_mem->lu_gp_assoc = 0;
1235                 }
1236                 spin_unlock(&lu_gp->lu_gp_lock);
1237                 lu_gp_mem->lu_gp = NULL;
1238         }
1239         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1240
1241         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1242 }
1243
1244 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1245 {
1246         struct t10_alua_lu_gp *lu_gp;
1247         struct config_item *ci;
1248
1249         spin_lock(&lu_gps_lock);
1250         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1251                 if (!lu_gp->lu_gp_valid_id)
1252                         continue;
1253                 ci = &lu_gp->lu_gp_group.cg_item;
1254                 if (!strcmp(config_item_name(ci), name)) {
1255                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1256                         spin_unlock(&lu_gps_lock);
1257                         return lu_gp;
1258                 }
1259         }
1260         spin_unlock(&lu_gps_lock);
1261
1262         return NULL;
1263 }
1264
1265 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1266 {
1267         spin_lock(&lu_gps_lock);
1268         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1269         spin_unlock(&lu_gps_lock);
1270 }
1271
1272 /*
1273  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1274  */
1275 void __core_alua_attach_lu_gp_mem(
1276         struct t10_alua_lu_gp_member *lu_gp_mem,
1277         struct t10_alua_lu_gp *lu_gp)
1278 {
1279         spin_lock(&lu_gp->lu_gp_lock);
1280         lu_gp_mem->lu_gp = lu_gp;
1281         lu_gp_mem->lu_gp_assoc = 1;
1282         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1283         lu_gp->lu_gp_members++;
1284         spin_unlock(&lu_gp->lu_gp_lock);
1285 }
1286
1287 /*
1288  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1289  */
1290 void __core_alua_drop_lu_gp_mem(
1291         struct t10_alua_lu_gp_member *lu_gp_mem,
1292         struct t10_alua_lu_gp *lu_gp)
1293 {
1294         spin_lock(&lu_gp->lu_gp_lock);
1295         list_del(&lu_gp_mem->lu_gp_mem_list);
1296         lu_gp_mem->lu_gp = NULL;
1297         lu_gp_mem->lu_gp_assoc = 0;
1298         lu_gp->lu_gp_members--;
1299         spin_unlock(&lu_gp->lu_gp_lock);
1300 }
1301
1302 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
1303         struct se_subsystem_dev *su_dev,
1304         const char *name,
1305         int def_group)
1306 {
1307         struct t10_alua_tg_pt_gp *tg_pt_gp;
1308
1309         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1310         if (!tg_pt_gp) {
1311                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1312                 return NULL;
1313         }
1314         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1315         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1316         mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1317         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1318         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1319         tg_pt_gp->tg_pt_gp_su_dev = su_dev;
1320         tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
1321         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1322                 ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
1323         /*
1324          * Enable both explict and implict ALUA support by default
1325          */
1326         tg_pt_gp->tg_pt_gp_alua_access_type =
1327                         TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
1328         /*
1329          * Set the default Active/NonOptimized Delay in milliseconds
1330          */
1331         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1332         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1333
1334         if (def_group) {
1335                 spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1336                 tg_pt_gp->tg_pt_gp_id =
1337                                 su_dev->t10_alua.alua_tg_pt_gps_counter++;
1338                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1339                 su_dev->t10_alua.alua_tg_pt_gps_count++;
1340                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1341                               &su_dev->t10_alua.tg_pt_gps_list);
1342                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1343         }
1344
1345         return tg_pt_gp;
1346 }
1347
1348 int core_alua_set_tg_pt_gp_id(
1349         struct t10_alua_tg_pt_gp *tg_pt_gp,
1350         u16 tg_pt_gp_id)
1351 {
1352         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1353         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1354         u16 tg_pt_gp_id_tmp;
1355         /*
1356          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1357          */
1358         if (tg_pt_gp->tg_pt_gp_valid_id) {
1359                 pr_warn("ALUA TG PT Group already has a valid ID,"
1360                         " ignoring request\n");
1361                 return -EINVAL;
1362         }
1363
1364         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1365         if (su_dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1366                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1367                         " 0x0000ffff reached\n");
1368                 spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1369                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1370                 return -ENOSPC;
1371         }
1372 again:
1373         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1374                         su_dev->t10_alua.alua_tg_pt_gps_counter++;
1375
1376         list_for_each_entry(tg_pt_gp_tmp, &su_dev->t10_alua.tg_pt_gps_list,
1377                         tg_pt_gp_list) {
1378                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1379                         if (!tg_pt_gp_id)
1380                                 goto again;
1381
1382                         pr_err("ALUA Target Port Group ID: %hu already"
1383                                 " exists, ignoring request\n", tg_pt_gp_id);
1384                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1385                         return -EINVAL;
1386                 }
1387         }
1388
1389         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1390         tg_pt_gp->tg_pt_gp_valid_id = 1;
1391         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1392                         &su_dev->t10_alua.tg_pt_gps_list);
1393         su_dev->t10_alua.alua_tg_pt_gps_count++;
1394         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1395
1396         return 0;
1397 }
1398
1399 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1400         struct se_port *port)
1401 {
1402         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1403
1404         tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1405                                 GFP_KERNEL);
1406         if (!tg_pt_gp_mem) {
1407                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1408                 return ERR_PTR(-ENOMEM);
1409         }
1410         INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1411         spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1412         atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1413
1414         tg_pt_gp_mem->tg_pt = port;
1415         port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1416         atomic_set(&port->sep_tg_pt_gp_active, 1);
1417
1418         return tg_pt_gp_mem;
1419 }
1420
1421 void core_alua_free_tg_pt_gp(
1422         struct t10_alua_tg_pt_gp *tg_pt_gp)
1423 {
1424         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1425         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1426         /*
1427          * Once we have reached this point, config_item_put() has already
1428          * been called from target_core_alua_drop_tg_pt_gp().
1429          *
1430          * Here we remove *tg_pt_gp from the global list so that
1431          * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
1432          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1433          */
1434         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1435         list_del(&tg_pt_gp->tg_pt_gp_list);
1436         su_dev->t10_alua.alua_tg_pt_gps_counter--;
1437         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1438         /*
1439          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1440          * core_alua_get_tg_pt_gp_by_name() in
1441          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1442          * to be released with core_alua_put_tg_pt_gp_from_name().
1443          */
1444         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1445                 cpu_relax();
1446         /*
1447          * Release reference to struct t10_alua_tg_pt_gp from all associated
1448          * struct se_port.
1449          */
1450         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1451         list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1452                         &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1453                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1454                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1455                         tg_pt_gp->tg_pt_gp_members--;
1456                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1457                 }
1458                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1459                 /*
1460                  * tg_pt_gp_mem is associated with a single
1461                  * se_port->sep_alua_tg_pt_gp_mem, and is released via
1462                  * core_alua_free_tg_pt_gp_mem().
1463                  *
1464                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1465                  * assume we want to re-assocate a given tg_pt_gp_mem with
1466                  * default_tg_pt_gp.
1467                  */
1468                 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1469                 if (tg_pt_gp != su_dev->t10_alua.default_tg_pt_gp) {
1470                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1471                                         su_dev->t10_alua.default_tg_pt_gp);
1472                 } else
1473                         tg_pt_gp_mem->tg_pt_gp = NULL;
1474                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1475
1476                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1477         }
1478         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1479
1480         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1481 }
1482
1483 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1484 {
1485         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1486         struct t10_alua *alua = &su_dev->t10_alua;
1487         struct t10_alua_tg_pt_gp *tg_pt_gp;
1488         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1489
1490         if (alua->alua_type != SPC3_ALUA_EMULATED)
1491                 return;
1492
1493         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1494         if (!tg_pt_gp_mem)
1495                 return;
1496
1497         while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1498                 cpu_relax();
1499
1500         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1501         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1502         if (tg_pt_gp) {
1503                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1504                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1505                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1506                         tg_pt_gp->tg_pt_gp_members--;
1507                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1508                 }
1509                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1510                 tg_pt_gp_mem->tg_pt_gp = NULL;
1511         }
1512         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1513
1514         kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1515 }
1516
1517 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1518         struct se_subsystem_dev *su_dev,
1519         const char *name)
1520 {
1521         struct t10_alua_tg_pt_gp *tg_pt_gp;
1522         struct config_item *ci;
1523
1524         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1525         list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
1526                         tg_pt_gp_list) {
1527                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1528                         continue;
1529                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1530                 if (!strcmp(config_item_name(ci), name)) {
1531                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1532                         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1533                         return tg_pt_gp;
1534                 }
1535         }
1536         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1537
1538         return NULL;
1539 }
1540
1541 static void core_alua_put_tg_pt_gp_from_name(
1542         struct t10_alua_tg_pt_gp *tg_pt_gp)
1543 {
1544         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1545
1546         spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
1547         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1548         spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
1549 }
1550
1551 /*
1552  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1553  */
1554 void __core_alua_attach_tg_pt_gp_mem(
1555         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1556         struct t10_alua_tg_pt_gp *tg_pt_gp)
1557 {
1558         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1559         tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1560         tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1561         list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1562                         &tg_pt_gp->tg_pt_gp_mem_list);
1563         tg_pt_gp->tg_pt_gp_members++;
1564         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1565 }
1566
1567 /*
1568  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1569  */
1570 static void __core_alua_drop_tg_pt_gp_mem(
1571         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1572         struct t10_alua_tg_pt_gp *tg_pt_gp)
1573 {
1574         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1575         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1576         tg_pt_gp_mem->tg_pt_gp = NULL;
1577         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1578         tg_pt_gp->tg_pt_gp_members--;
1579         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1580 }
1581
1582 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1583 {
1584         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1585         struct config_item *tg_pt_ci;
1586         struct t10_alua *alua = &su_dev->t10_alua;
1587         struct t10_alua_tg_pt_gp *tg_pt_gp;
1588         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1589         ssize_t len = 0;
1590
1591         if (alua->alua_type != SPC3_ALUA_EMULATED)
1592                 return len;
1593
1594         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1595         if (!tg_pt_gp_mem)
1596                 return len;
1597
1598         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1599         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1600         if (tg_pt_gp) {
1601                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1602                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1603                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1604                         "Primary Access Status: %s\nTG Port Secondary Access"
1605                         " State: %s\nTG Port Secondary Access Status: %s\n",
1606                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1607                         core_alua_dump_state(atomic_read(
1608                                         &tg_pt_gp->tg_pt_gp_alua_access_state)),
1609                         core_alua_dump_status(
1610                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1611                         (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
1612                         "Offline" : "None",
1613                         core_alua_dump_status(port->sep_tg_pt_secondary_stat));
1614         }
1615         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1616
1617         return len;
1618 }
1619
1620 ssize_t core_alua_store_tg_pt_gp_info(
1621         struct se_port *port,
1622         const char *page,
1623         size_t count)
1624 {
1625         struct se_portal_group *tpg;
1626         struct se_lun *lun;
1627         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1628         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1629         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1630         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1631         int move = 0;
1632
1633         tpg = port->sep_tpg;
1634         lun = port->sep_lun;
1635
1636         if (su_dev->t10_alua.alua_type != SPC3_ALUA_EMULATED) {
1637                 pr_warn("SPC3_ALUA_EMULATED not enabled for"
1638                         " %s/tpgt_%hu/%s\n", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1639                         tpg->se_tpg_tfo->tpg_get_tag(tpg),
1640                         config_item_name(&lun->lun_group.cg_item));
1641                 return -EINVAL;
1642         }
1643
1644         if (count > TG_PT_GROUP_NAME_BUF) {
1645                 pr_err("ALUA Target Port Group alias too large!\n");
1646                 return -EINVAL;
1647         }
1648         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1649         memcpy(buf, page, count);
1650         /*
1651          * Any ALUA target port group alias besides "NULL" means we will be
1652          * making a new group association.
1653          */
1654         if (strcmp(strstrip(buf), "NULL")) {
1655                 /*
1656                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1657                  * struct t10_alua_tg_pt_gp.  This reference is released with
1658                  * core_alua_put_tg_pt_gp_from_name() below.
1659                  */
1660                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
1661                                         strstrip(buf));
1662                 if (!tg_pt_gp_new)
1663                         return -ENODEV;
1664         }
1665         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1666         if (!tg_pt_gp_mem) {
1667                 if (tg_pt_gp_new)
1668                         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1669                 pr_err("NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
1670                 return -EINVAL;
1671         }
1672
1673         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1674         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1675         if (tg_pt_gp) {
1676                 /*
1677                  * Clearing an existing tg_pt_gp association, and replacing
1678                  * with the default_tg_pt_gp.
1679                  */
1680                 if (!tg_pt_gp_new) {
1681                         pr_debug("Target_Core_ConfigFS: Moving"
1682                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1683                                 " alua/%s, ID: %hu back to"
1684                                 " default_tg_pt_gp\n",
1685                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1686                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1687                                 config_item_name(&lun->lun_group.cg_item),
1688                                 config_item_name(
1689                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1690                                 tg_pt_gp->tg_pt_gp_id);
1691
1692                         __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1693                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1694                                         su_dev->t10_alua.default_tg_pt_gp);
1695                         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1696
1697                         return count;
1698                 }
1699                 /*
1700                  * Removing existing association of tg_pt_gp_mem with tg_pt_gp
1701                  */
1702                 __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1703                 move = 1;
1704         }
1705         /*
1706          * Associate tg_pt_gp_mem with tg_pt_gp_new.
1707          */
1708         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
1709         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1710         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1711                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1712                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1713                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1714                 config_item_name(&lun->lun_group.cg_item),
1715                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1716                 tg_pt_gp_new->tg_pt_gp_id);
1717
1718         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1719         return count;
1720 }
1721
1722 ssize_t core_alua_show_access_type(
1723         struct t10_alua_tg_pt_gp *tg_pt_gp,
1724         char *page)
1725 {
1726         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
1727             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
1728                 return sprintf(page, "Implict and Explict\n");
1729         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
1730                 return sprintf(page, "Implict\n");
1731         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
1732                 return sprintf(page, "Explict\n");
1733         else
1734                 return sprintf(page, "None\n");
1735 }
1736
1737 ssize_t core_alua_store_access_type(
1738         struct t10_alua_tg_pt_gp *tg_pt_gp,
1739         const char *page,
1740         size_t count)
1741 {
1742         unsigned long tmp;
1743         int ret;
1744
1745         ret = strict_strtoul(page, 0, &tmp);
1746         if (ret < 0) {
1747                 pr_err("Unable to extract alua_access_type\n");
1748                 return -EINVAL;
1749         }
1750         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
1751                 pr_err("Illegal value for alua_access_type:"
1752                                 " %lu\n", tmp);
1753                 return -EINVAL;
1754         }
1755         if (tmp == 3)
1756                 tg_pt_gp->tg_pt_gp_alua_access_type =
1757                         TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
1758         else if (tmp == 2)
1759                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
1760         else if (tmp == 1)
1761                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
1762         else
1763                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
1764
1765         return count;
1766 }
1767
1768 ssize_t core_alua_show_nonop_delay_msecs(
1769         struct t10_alua_tg_pt_gp *tg_pt_gp,
1770         char *page)
1771 {
1772         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
1773 }
1774
1775 ssize_t core_alua_store_nonop_delay_msecs(
1776         struct t10_alua_tg_pt_gp *tg_pt_gp,
1777         const char *page,
1778         size_t count)
1779 {
1780         unsigned long tmp;
1781         int ret;
1782
1783         ret = strict_strtoul(page, 0, &tmp);
1784         if (ret < 0) {
1785                 pr_err("Unable to extract nonop_delay_msecs\n");
1786                 return -EINVAL;
1787         }
1788         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
1789                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
1790                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
1791                         ALUA_MAX_NONOP_DELAY_MSECS);
1792                 return -EINVAL;
1793         }
1794         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
1795
1796         return count;
1797 }
1798
1799 ssize_t core_alua_show_trans_delay_msecs(
1800         struct t10_alua_tg_pt_gp *tg_pt_gp,
1801         char *page)
1802 {
1803         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1804 }
1805
1806 ssize_t core_alua_store_trans_delay_msecs(
1807         struct t10_alua_tg_pt_gp *tg_pt_gp,
1808         const char *page,
1809         size_t count)
1810 {
1811         unsigned long tmp;
1812         int ret;
1813
1814         ret = strict_strtoul(page, 0, &tmp);
1815         if (ret < 0) {
1816                 pr_err("Unable to extract trans_delay_msecs\n");
1817                 return -EINVAL;
1818         }
1819         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
1820                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
1821                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
1822                         ALUA_MAX_TRANS_DELAY_MSECS);
1823                 return -EINVAL;
1824         }
1825         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
1826
1827         return count;
1828 }
1829
1830 ssize_t core_alua_show_preferred_bit(
1831         struct t10_alua_tg_pt_gp *tg_pt_gp,
1832         char *page)
1833 {
1834         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
1835 }
1836
1837 ssize_t core_alua_store_preferred_bit(
1838         struct t10_alua_tg_pt_gp *tg_pt_gp,
1839         const char *page,
1840         size_t count)
1841 {
1842         unsigned long tmp;
1843         int ret;
1844
1845         ret = strict_strtoul(page, 0, &tmp);
1846         if (ret < 0) {
1847                 pr_err("Unable to extract preferred ALUA value\n");
1848                 return -EINVAL;
1849         }
1850         if ((tmp != 0) && (tmp != 1)) {
1851                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
1852                 return -EINVAL;
1853         }
1854         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
1855
1856         return count;
1857 }
1858
1859 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
1860 {
1861         if (!lun->lun_sep)
1862                 return -ENODEV;
1863
1864         return sprintf(page, "%d\n",
1865                 atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
1866 }
1867
1868 ssize_t core_alua_store_offline_bit(
1869         struct se_lun *lun,
1870         const char *page,
1871         size_t count)
1872 {
1873         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1874         unsigned long tmp;
1875         int ret;
1876
1877         if (!lun->lun_sep)
1878                 return -ENODEV;
1879
1880         ret = strict_strtoul(page, 0, &tmp);
1881         if (ret < 0) {
1882                 pr_err("Unable to extract alua_tg_pt_offline value\n");
1883                 return -EINVAL;
1884         }
1885         if ((tmp != 0) && (tmp != 1)) {
1886                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
1887                                 tmp);
1888                 return -EINVAL;
1889         }
1890         tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
1891         if (!tg_pt_gp_mem) {
1892                 pr_err("Unable to locate *tg_pt_gp_mem\n");
1893                 return -EINVAL;
1894         }
1895
1896         ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
1897                         lun->lun_sep, 0, (int)tmp);
1898         if (ret < 0)
1899                 return -EINVAL;
1900
1901         return count;
1902 }
1903
1904 ssize_t core_alua_show_secondary_status(
1905         struct se_lun *lun,
1906         char *page)
1907 {
1908         return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
1909 }
1910
1911 ssize_t core_alua_store_secondary_status(
1912         struct se_lun *lun,
1913         const char *page,
1914         size_t count)
1915 {
1916         unsigned long tmp;
1917         int ret;
1918
1919         ret = strict_strtoul(page, 0, &tmp);
1920         if (ret < 0) {
1921                 pr_err("Unable to extract alua_tg_pt_status\n");
1922                 return -EINVAL;
1923         }
1924         if ((tmp != ALUA_STATUS_NONE) &&
1925             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
1926             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
1927                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
1928                                 tmp);
1929                 return -EINVAL;
1930         }
1931         lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
1932
1933         return count;
1934 }
1935
1936 ssize_t core_alua_show_secondary_write_metadata(
1937         struct se_lun *lun,
1938         char *page)
1939 {
1940         return sprintf(page, "%d\n",
1941                         lun->lun_sep->sep_tg_pt_secondary_write_md);
1942 }
1943
1944 ssize_t core_alua_store_secondary_write_metadata(
1945         struct se_lun *lun,
1946         const char *page,
1947         size_t count)
1948 {
1949         unsigned long tmp;
1950         int ret;
1951
1952         ret = strict_strtoul(page, 0, &tmp);
1953         if (ret < 0) {
1954                 pr_err("Unable to extract alua_tg_pt_write_md\n");
1955                 return -EINVAL;
1956         }
1957         if ((tmp != 0) && (tmp != 1)) {
1958                 pr_err("Illegal value for alua_tg_pt_write_md:"
1959                                 " %lu\n", tmp);
1960                 return -EINVAL;
1961         }
1962         lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
1963
1964         return count;
1965 }
1966
1967 int core_setup_alua(struct se_device *dev, int force_pt)
1968 {
1969         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1970         struct t10_alua *alua = &su_dev->t10_alua;
1971         struct t10_alua_lu_gp_member *lu_gp_mem;
1972         /*
1973          * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
1974          * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
1975          * cause a problem because libata and some SATA RAID HBAs appear
1976          * under Linux/SCSI, but emulate SCSI logic themselves.
1977          */
1978         if (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
1979             !(dev->se_sub_dev->se_dev_attrib.emulate_alua)) || force_pt) {
1980                 alua->alua_type = SPC_ALUA_PASSTHROUGH;
1981                 alua->alua_state_check = &core_alua_state_check_nop;
1982                 pr_debug("%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
1983                         " emulation\n", dev->transport->name);
1984                 return 0;
1985         }
1986         /*
1987          * If SPC-3 or above is reported by real or emulated struct se_device,
1988          * use emulated ALUA.
1989          */
1990         if (dev->transport->get_device_rev(dev) >= SCSI_3) {
1991                 pr_debug("%s: Enabling ALUA Emulation for SPC-3"
1992                         " device\n", dev->transport->name);
1993                 /*
1994                  * Associate this struct se_device with the default ALUA
1995                  * LUN Group.
1996                  */
1997                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
1998                 if (IS_ERR(lu_gp_mem))
1999                         return PTR_ERR(lu_gp_mem);
2000
2001                 alua->alua_type = SPC3_ALUA_EMULATED;
2002                 alua->alua_state_check = &core_alua_state_check;
2003                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2004                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2005                                 default_lu_gp);
2006                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2007
2008                 pr_debug("%s: Adding to default ALUA LU Group:"
2009                         " core/alua/lu_gps/default_lu_gp\n",
2010                         dev->transport->name);
2011         } else {
2012                 alua->alua_type = SPC2_ALUA_DISABLED;
2013                 alua->alua_state_check = &core_alua_state_check_nop;
2014                 pr_debug("%s: Disabling ALUA Emulation for SPC-2"
2015                         " device\n", dev->transport->name);
2016         }
2017
2018         return 0;
2019 }