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 /*
  50  * REPORT_TARGET_PORT_GROUPS
  51  *
  52  * See spc4r17 section 6.27
  53  */
  54 int core_emulate_report_target_port_groups(struct se_cmd *cmd)
  55 {
  56         struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
  57         struct se_port *port;
  58         struct t10_alua_tg_pt_gp *tg_pt_gp;
  59         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
  60         unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
  61         u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
  62                                     Target port group descriptor */
  63
  64         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
  65         list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
  66                         tg_pt_gp_list) {
  67                 /*
  68                  * PREF: Preferred target port bit, determine if this
  69                  * bit should be set for port group.
  70                  */
  71                 if (tg_pt_gp->tg_pt_gp_pref)
  72                         buf[off] = 0x80;
  73                 /*
  74                  * Set the ASYMMETRIC ACCESS State
  75                  */
  76                 buf[off++] |= (atomic_read(
  77                         &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
  78                 /*
  79                  * Set supported ASYMMETRIC ACCESS State bits
  80                  */
  81                 buf[off] = 0x80; /* T_SUP */
  82                 buf[off] |= 0x40; /* O_SUP */
  83                 buf[off] |= 0x8; /* U_SUP */
  84                 buf[off] |= 0x4; /* S_SUP */
  85                 buf[off] |= 0x2; /* AN_SUP */
  86                 buf[off++] |= 0x1; /* AO_SUP */
  87                 /*
  88                  * TARGET PORT GROUP
  89                  */
  90                 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
  91                 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
  92
  93                 off++; /* Skip over Reserved */
  94                 /*
  95                  * STATUS CODE
  96                  */
  97                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
  98                 /*
  99                  * Vendor Specific field
 100                  */
 101                 buf[off++] = 0x00;
 102                 /*
 103                  * TARGET PORT COUNT
 104                  */
 105                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
 106                 rd_len += 8;
 107
 108                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 109                 list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
 110                                 tg_pt_gp_mem_list) {
 111                         port = tg_pt_gp_mem->tg_pt;
 112                         /*
 113                          * Start Target Port descriptor format
 114                          *
 115                          * See spc4r17 section 6.2.7 Table 247
 116                          */
 117                         off += 2; /* Skip over Obsolete */
 118                         /*
 119                          * Set RELATIVE TARGET PORT IDENTIFIER
 120                          */
 121                         buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
 122                         buf[off++] = (port->sep_rtpi & 0xff);
 123                         rd_len += 4;
 124                 }
 125                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 126         }
 127         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 128         /*
 129          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
 130          */
 131         buf[0] = ((rd_len >> 24) & 0xff);
 132         buf[1] = ((rd_len >> 16) & 0xff);
 133         buf[2] = ((rd_len >> 8) & 0xff);
 134         buf[3] = (rd_len & 0xff);
 135
 136         return 0;
 137 }
 138
 139 /*
 140  * SET_TARGET_PORT_GROUPS for explict ALUA operation.
 141  *
 142  * See spc4r17 section 6.35
 143  */
 144 int core_emulate_set_target_port_groups(struct se_cmd *cmd)
 145 {
 146         struct se_device *dev = SE_DEV(cmd);
 147         struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
 148         struct se_port *port, *l_port = SE_LUN(cmd)->lun_sep;
 149         struct se_node_acl *nacl = SE_SESS(cmd)->se_node_acl;
 150         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
 151         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
 152         unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
 153         unsigned char *ptr = &buf[4]; /* Skip over RESERVED area in header */
 154         u32 len = 4; /* Skip over RESERVED area in header */
 155         int alua_access_state, primary = 0, rc;
 156         u16 tg_pt_id, rtpi;
 157
 158         if (!(l_port))
 159                 return PYX_TRANSPORT_LU_COMM_FAILURE;
 160         /*
 161          * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
 162          * for the local tg_pt_gp.
 163          */
 164         l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
 165         if (!(l_tg_pt_gp_mem)) {
 166                 printk(KERN_ERR "Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
 167                 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 168         }
 169         spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 170         l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
 171         if (!(l_tg_pt_gp)) {
 172                 spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 173                 printk(KERN_ERR "Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
 174                 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 175         }
 176         rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
 177         spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
 178
 179         if (!(rc)) {
 180                 printk(KERN_INFO "Unable to process SET_TARGET_PORT_GROUPS"
 181                                 " while TPGS_EXPLICT_ALUA is disabled\n");
 182                 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
 183         }
 184
 185         while (len < cmd->data_length) {
 186                 alua_access_state = (ptr[0] & 0x0f);
 187                 /*
 188                  * Check the received ALUA access state, and determine if
 189                  * the state is a primary or secondary target port asymmetric
 190                  * access state.
 191                  */
 192                 rc = core_alua_check_transition(alua_access_state, &primary);
 193                 if (rc != 0) {
 194                         /*
 195                          * If the SET TARGET PORT GROUPS attempts to establish
 196                          * an invalid combination of target port asymmetric
 197                          * access states or attempts to establish an
 198                          * unsupported target port asymmetric access state,
 199                          * then the command shall be terminated with CHECK
 200                          * CONDITION status, with the sense key set to ILLEGAL
 201                          * REQUEST, and the additional sense code set to INVALID
 202                          * FIELD IN PARAMETER LIST.
 203                          */
 204                         return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 205                 }
 206                 rc = -1;
 207                 /*
 208                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
 209                  * specifies a primary target port asymmetric access state,
 210                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
 211                  * a primary target port group for which the primary target
 212                  * port asymmetric access state shall be changed. If the
 213                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
 214                  * port asymmetric access state, then the TARGET PORT GROUP OR
 215                  * TARGET PORT field specifies the relative target port
 216                  * identifier (see 3.1.120) of the target port for which the
 217                  * secondary target port asymmetric access state shall be
 218                  * changed.
 219                  */
 220                 if (primary) {
 221                         tg_pt_id = ((ptr[2] << 8) & 0xff);
 222                         tg_pt_id |= (ptr[3] & 0xff);
 223                         /*
 224                          * Locate the matching target port group ID from
 225                          * the global tg_pt_gp list
 226                          */
 227                         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 228                         list_for_each_entry(tg_pt_gp,
 229                                         &T10_ALUA(su_dev)->tg_pt_gps_list,
 230                                         tg_pt_gp_list) {
 231                                 if (!(tg_pt_gp->tg_pt_gp_valid_id))
 232                                         continue;
 233
 234                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
 235                                         continue;
 236
 237                                 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 238                                 smp_mb__after_atomic_inc();
 239                                 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 240
 241                                 rc = core_alua_do_port_transition(tg_pt_gp,
 242                                                 dev, l_port, nacl,
 243                                                 alua_access_state, 1);
 244
 245                                 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 246                                 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 247                                 smp_mb__after_atomic_dec();
 248                                 break;
 249                         }
 250                         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 251                         /*
 252                          * If not matching target port group ID can be located
 253                          * throw an exception with ASCQ: INVALID_PARAMETER_LIST
 254                          */
 255                         if (rc != 0)
 256                                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 257                 } else {
 258                         /*
 259                          * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
 260                          * the Target Port in question for the the incoming
 261                          * SET_TARGET_PORT_GROUPS op.
 262                          */
 263                         rtpi = ((ptr[2] << 8) & 0xff);
 264                         rtpi |= (ptr[3] & 0xff);
 265                         /*
 266                          * Locate the matching relative target port identifer
 267                          * for the struct se_device storage object.
 268                          */
 269                         spin_lock(&dev->se_port_lock);
 270                         list_for_each_entry(port, &dev->dev_sep_list,
 271                                                         sep_list) {
 272                                 if (port->sep_rtpi != rtpi)
 273                                         continue;
 274
 275                                 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 276                                 spin_unlock(&dev->se_port_lock);
 277
 278                                 rc = core_alua_set_tg_pt_secondary_state(
 279                                                 tg_pt_gp_mem, port, 1, 1);
 280
 281                                 spin_lock(&dev->se_port_lock);
 282                                 break;
 283                         }
 284                         spin_unlock(&dev->se_port_lock);
 285                         /*
 286                          * If not matching relative target port identifier can
 287                          * be located, throw an exception with ASCQ:
 288                          * INVALID_PARAMETER_LIST
 289                          */
 290                         if (rc != 0)
 291                                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
 292                 }
 293
 294                 ptr += 4;
 295                 len += 4;
 296         }
 297
 298         return 0;
 299 }
 300
 301 static inline int core_alua_state_nonoptimized(
 302         struct se_cmd *cmd,
 303         unsigned char *cdb,
 304         int nonop_delay_msecs,
 305         u8 *alua_ascq)
 306 {
 307         /*
 308          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
 309          * later to determine if processing of this cmd needs to be
 310          * temporarily delayed for the Active/NonOptimized primary access state.
 311          */
 312         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
 313         cmd->alua_nonop_delay = nonop_delay_msecs;
 314         return 0;
 315 }
 316
 317 static inline int core_alua_state_standby(
 318         struct se_cmd *cmd,
 319         unsigned char *cdb,
 320         u8 *alua_ascq)
 321 {
 322         /*
 323          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
 324          * spc4r17 section 5.9.2.4.4
 325          */
 326         switch (cdb[0]) {
 327         case INQUIRY:
 328         case LOG_SELECT:
 329         case LOG_SENSE:
 330         case MODE_SELECT:
 331         case MODE_SENSE:
 332         case REPORT_LUNS:
 333         case RECEIVE_DIAGNOSTIC:
 334         case SEND_DIAGNOSTIC:
 335         case MAINTENANCE_IN:
 336                 switch (cdb[1]) {
 337                 case MI_REPORT_TARGET_PGS:
 338                         return 0;
 339                 default:
 340                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 341                         return 1;
 342                 }
 343         case MAINTENANCE_OUT:
 344                 switch (cdb[1]) {
 345                 case MO_SET_TARGET_PGS:
 346                         return 0;
 347                 default:
 348                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 349                         return 1;
 350                 }
 351         case REQUEST_SENSE:
 352         case PERSISTENT_RESERVE_IN:
 353         case PERSISTENT_RESERVE_OUT:
 354         case READ_BUFFER:
 355         case WRITE_BUFFER:
 356                 return 0;
 357         default:
 358                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
 359                 return 1;
 360         }
 361
 362         return 0;
 363 }
 364
 365 static inline int core_alua_state_unavailable(
 366         struct se_cmd *cmd,
 367         unsigned char *cdb,
 368         u8 *alua_ascq)
 369 {
 370         /*
 371          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
 372          * spc4r17 section 5.9.2.4.5
 373          */
 374         switch (cdb[0]) {
 375         case INQUIRY:
 376         case REPORT_LUNS:
 377         case MAINTENANCE_IN:
 378                 switch (cdb[1]) {
 379                 case MI_REPORT_TARGET_PGS:
 380                         return 0;
 381                 default:
 382                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 383                         return 1;
 384                 }
 385         case MAINTENANCE_OUT:
 386                 switch (cdb[1]) {
 387                 case MO_SET_TARGET_PGS:
 388                         return 0;
 389                 default:
 390                         *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 391                         return 1;
 392                 }
 393         case REQUEST_SENSE:
 394         case READ_BUFFER:
 395         case WRITE_BUFFER:
 396                 return 0;
 397         default:
 398                 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
 399                 return 1;
 400         }
 401
 402         return 0;
 403 }
 404
 405 static inline int core_alua_state_transition(
 406         struct se_cmd *cmd,
 407         unsigned char *cdb,
 408         u8 *alua_ascq)
 409 {
 410         /*
 411          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
 412          * spc4r17 section 5.9.2.5
 413          */
 414         switch (cdb[0]) {
 415         case INQUIRY:
 416         case REPORT_LUNS:
 417         case MAINTENANCE_IN:
 418                 switch (cdb[1]) {
 419                 case MI_REPORT_TARGET_PGS:
 420                         return 0;
 421                 default:
 422                         *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 423                         return 1;
 424                 }
 425         case REQUEST_SENSE:
 426         case READ_BUFFER:
 427         case WRITE_BUFFER:
 428                 return 0;
 429         default:
 430                 *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
 431                 return 1;
 432         }
 433
 434         return 0;
 435 }
 436
 437 /*
 438  * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
 439  * in transport_cmd_sequencer().  This function is assigned to
 440  * struct t10_alua *->state_check() in core_setup_alua()
 441  */
 442 static int core_alua_state_check_nop(
 443         struct se_cmd *cmd,
 444         unsigned char *cdb,
 445         u8 *alua_ascq)
 446 {
 447         return 0;
 448 }
 449
 450 /*
 451  * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
 452  * This function is assigned to struct t10_alua *->state_check() in
 453  * core_setup_alua()
 454  *
 455  * Also, this function can return three different return codes to
 456  * signal transport_generic_cmd_sequencer()
 457  *
 458  * return 1: Is used to signal LUN not accecsable, and check condition/not ready
 459  * return 0: Used to signal success
 460  * reutrn -1: Used to signal failure, and invalid cdb field
 461  */
 462 static int core_alua_state_check(
 463         struct se_cmd *cmd,
 464         unsigned char *cdb,
 465         u8 *alua_ascq)
 466 {
 467         struct se_lun *lun = SE_LUN(cmd);
 468         struct se_port *port = lun->lun_sep;
 469         struct t10_alua_tg_pt_gp *tg_pt_gp;
 470         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
 471         int out_alua_state, nonop_delay_msecs;
 472
 473         if (!(port))
 474                 return 0;
 475         /*
 476          * First, check for a struct se_port specific secondary ALUA target port
 477          * access state: OFFLINE
 478          */
 479         if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
 480                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 481                 printk(KERN_INFO "ALUA: Got secondary offline status for local"
 482                                 " target port\n");
 483                 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
 484                 return 1;
 485         }
 486          /*
 487          * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
 488          * ALUA target port group, to obtain current ALUA access state.
 489          * Otherwise look for the underlying struct se_device association with
 490          * a ALUA logical unit group.
 491          */
 492         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
 493         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 494         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
 495         out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 496         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
 497         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 498         /*
 499          * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a separate conditional
 500          * statement so the compiler knows explicitly to check this case first.
 501          * For the Optimized ALUA access state case, we want to process the
 502          * incoming fabric cmd ASAP..
 503          */
 504         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
 505                 return 0;
 506
 507         switch (out_alua_state) {
 508         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 509                 return core_alua_state_nonoptimized(cmd, cdb,
 510                                         nonop_delay_msecs, alua_ascq);
 511         case ALUA_ACCESS_STATE_STANDBY:
 512                 return core_alua_state_standby(cmd, cdb, alua_ascq);
 513         case ALUA_ACCESS_STATE_UNAVAILABLE:
 514                 return core_alua_state_unavailable(cmd, cdb, alua_ascq);
 515         case ALUA_ACCESS_STATE_TRANSITION:
 516                 return core_alua_state_transition(cmd, cdb, alua_ascq);
 517         /*
 518          * OFFLINE is a secondary ALUA target port group access state, that is
 519          * handled above with struct se_port->sep_tg_pt_secondary_offline=1
 520          */
 521         case ALUA_ACCESS_STATE_OFFLINE:
 522         default:
 523                 printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n",
 524                                 out_alua_state);
 525                 return -1;
 526         }
 527
 528         return 0;
 529 }
 530
 531 /*
 532  * Check implict and explict ALUA state change request.
 533  */
 534 static int core_alua_check_transition(int state, int *primary)
 535 {
 536         switch (state) {
 537         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 538         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 539         case ALUA_ACCESS_STATE_STANDBY:
 540         case ALUA_ACCESS_STATE_UNAVAILABLE:
 541                 /*
 542                  * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
 543                  * defined as primary target port asymmetric access states.
 544                  */
 545                 *primary = 1;
 546                 break;
 547         case ALUA_ACCESS_STATE_OFFLINE:
 548                 /*
 549                  * OFFLINE state is defined as a secondary target port
 550                  * asymmetric access state.
 551                  */
 552                 *primary = 0;
 553                 break;
 554         default:
 555                 printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n", state);
 556                 return -1;
 557         }
 558
 559         return 0;
 560 }
 561
 562 static char *core_alua_dump_state(int state)
 563 {
 564         switch (state) {
 565         case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
 566                 return "Active/Optimized";
 567         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
 568                 return "Active/NonOptimized";
 569         case ALUA_ACCESS_STATE_STANDBY:
 570                 return "Standby";
 571         case ALUA_ACCESS_STATE_UNAVAILABLE:
 572                 return "Unavailable";
 573         case ALUA_ACCESS_STATE_OFFLINE:
 574                 return "Offline";
 575         default:
 576                 return "Unknown";
 577         }
 578
 579         return NULL;
 580 }
 581
 582 char *core_alua_dump_status(int status)
 583 {
 584         switch (status) {
 585         case ALUA_STATUS_NONE:
 586                 return "None";
 587         case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
 588                 return "Altered by Explict STPG";
 589         case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
 590                 return "Altered by Implict ALUA";
 591         default:
 592                 return "Unknown";
 593         }
 594
 595         return NULL;
 596 }
 597
 598 /*
 599  * Used by fabric modules to determine when we need to delay processing
 600  * for the Active/NonOptimized paths..
 601  */
 602 int core_alua_check_nonop_delay(
 603         struct se_cmd *cmd)
 604 {
 605         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
 606                 return 0;
 607         if (in_interrupt())
 608                 return 0;
 609         /*
 610          * The ALUA Active/NonOptimized access state delay can be disabled
 611          * in via configfs with a value of zero
 612          */
 613         if (!(cmd->alua_nonop_delay))
 614                 return 0;
 615         /*
 616          * struct se_cmd->alua_nonop_delay gets set by a target port group
 617          * defined interval in core_alua_state_nonoptimized()
 618          */
 619         msleep_interruptible(cmd->alua_nonop_delay);
 620         return 0;
 621 }
 622 EXPORT_SYMBOL(core_alua_check_nonop_delay);
 623
 624 /*
 625  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
 626  *
 627  */
 628 static int core_alua_write_tpg_metadata(
 629         const char *path,
 630         unsigned char *md_buf,
 631         u32 md_buf_len)
 632 {
 633         mm_segment_t old_fs;
 634         struct file *file;
 635         struct iovec iov[1];
 636         int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
 637
 638         memset(iov, 0, sizeof(struct iovec));
 639
 640         file = filp_open(path, flags, 0600);
 641         if (IS_ERR(file) || !file || !file->f_dentry) {
 642                 printk(KERN_ERR "filp_open(%s) for ALUA metadata failed\n",
 643                         path);
 644                 return -ENODEV;
 645         }
 646
 647         iov[0].iov_base = &md_buf[0];
 648         iov[0].iov_len = md_buf_len;
 649
 650         old_fs = get_fs();
 651         set_fs(get_ds());
 652         ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
 653         set_fs(old_fs);
 654
 655         if (ret < 0) {
 656                 printk(KERN_ERR "Error writing ALUA metadata file: %s\n", path);
 657                 filp_close(file, NULL);
 658                 return -EIO;
 659         }
 660         filp_close(file, NULL);
 661
 662         return 0;
 663 }
 664
 665 /*
 666  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
 667  */
 668 static int core_alua_update_tpg_primary_metadata(
 669         struct t10_alua_tg_pt_gp *tg_pt_gp,
 670         int primary_state,
 671         unsigned char *md_buf)
 672 {
 673         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
 674         struct t10_wwn *wwn = &su_dev->t10_wwn;
 675         char path[ALUA_METADATA_PATH_LEN];
 676         int len;
 677
 678         memset(path, 0, ALUA_METADATA_PATH_LEN);
 679
 680         len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
 681                         "tg_pt_gp_id=%hu\n"
 682                         "alua_access_state=0x%02x\n"
 683                         "alua_access_status=0x%02x\n",
 684                         tg_pt_gp->tg_pt_gp_id, primary_state,
 685                         tg_pt_gp->tg_pt_gp_alua_access_status);
 686
 687         snprintf(path, ALUA_METADATA_PATH_LEN,
 688                 "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
 689                 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
 690
 691         return core_alua_write_tpg_metadata(path, md_buf, len);
 692 }
 693
 694 static int core_alua_do_transition_tg_pt(
 695         struct t10_alua_tg_pt_gp *tg_pt_gp,
 696         struct se_port *l_port,
 697         struct se_node_acl *nacl,
 698         unsigned char *md_buf,
 699         int new_state,
 700         int explict)
 701 {
 702         struct se_dev_entry *se_deve;
 703         struct se_lun_acl *lacl;
 704         struct se_port *port;
 705         struct t10_alua_tg_pt_gp_member *mem;
 706         int old_state = 0;
 707         /*
 708          * Save the old primary ALUA access state, and set the current state
 709          * to ALUA_ACCESS_STATE_TRANSITION.
 710          */
 711         old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
 712         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
 713                         ALUA_ACCESS_STATE_TRANSITION);
 714         tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
 715                                 ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
 716                                 ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
 717         /*
 718          * Check for the optional ALUA primary state transition delay
 719          */
 720         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
 721                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
 722
 723         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 724         list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
 725                                 tg_pt_gp_mem_list) {
 726                 port = mem->tg_pt;
 727                 /*
 728                  * After an implicit target port asymmetric access state
 729                  * change, a device server shall establish a unit attention
 730                  * condition for the initiator port associated with every I_T
 731                  * nexus with the additional sense code set to ASYMMETRIC
 732                  * ACCESS STATE CHAGED.
 733                  *
 734                  * After an explicit target port asymmetric access state
 735                  * change, a device server shall establish a unit attention
 736                  * condition with the additional sense code set to ASYMMETRIC
 737                  * ACCESS STATE CHANGED for the initiator port associated with
 738                  * every I_T nexus other than the I_T nexus on which the SET
 739                  * TARGET PORT GROUPS command
 740                  */
 741                 atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
 742                 smp_mb__after_atomic_inc();
 743                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 744
 745                 spin_lock_bh(&port->sep_alua_lock);
 746                 list_for_each_entry(se_deve, &port->sep_alua_list,
 747                                         alua_port_list) {
 748                         lacl = se_deve->se_lun_acl;
 749                         /*
 750                          * se_deve->se_lun_acl pointer may be NULL for a
 751                          * entry created without explict Node+MappedLUN ACLs
 752                          */
 753                         if (!(lacl))
 754                                 continue;
 755
 756                         if (explict &&
 757                            (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
 758                            (l_port != NULL) && (l_port == port))
 759                                 continue;
 760
 761                         core_scsi3_ua_allocate(lacl->se_lun_nacl,
 762                                 se_deve->mapped_lun, 0x2A,
 763                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
 764                 }
 765                 spin_unlock_bh(&port->sep_alua_lock);
 766
 767                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
 768                 atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
 769                 smp_mb__after_atomic_dec();
 770         }
 771         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
 772         /*
 773          * Update the ALUA metadata buf that has been allocated in
 774          * core_alua_do_port_transition(), this metadata will be written
 775          * to struct file.
 776          *
 777          * Note that there is the case where we do not want to update the
 778          * metadata when the saved metadata is being parsed in userspace
 779          * when setting the existing port access state and access status.
 780          *
 781          * Also note that the failure to write out the ALUA metadata to
 782          * struct file does NOT affect the actual ALUA transition.
 783          */
 784         if (tg_pt_gp->tg_pt_gp_write_metadata) {
 785                 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
 786                 core_alua_update_tpg_primary_metadata(tg_pt_gp,
 787                                         new_state, md_buf);
 788                 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
 789         }
 790         /*
 791          * Set the current primary ALUA access state to the requested new state
 792          */
 793         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
 794
 795         printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
 796                 " from primary access state %s to %s\n", (explict) ? "explict" :
 797                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
 798                 tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
 799                 core_alua_dump_state(new_state));
 800
 801         return 0;
 802 }
 803
 804 int core_alua_do_port_transition(
 805         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
 806         struct se_device *l_dev,
 807         struct se_port *l_port,
 808         struct se_node_acl *l_nacl,
 809         int new_state,
 810         int explict)
 811 {
 812         struct se_device *dev;
 813         struct se_port *port;
 814         struct se_subsystem_dev *su_dev;
 815         struct se_node_acl *nacl;
 816         struct t10_alua_lu_gp *lu_gp;
 817         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
 818         struct t10_alua_tg_pt_gp *tg_pt_gp;
 819         unsigned char *md_buf;
 820         int primary;
 821
 822         if (core_alua_check_transition(new_state, &primary) != 0)
 823                 return -EINVAL;
 824
 825         md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
 826         if (!(md_buf)) {
 827                 printk("Unable to allocate buf for ALUA metadata\n");
 828                 return -ENOMEM;
 829         }
 830
 831         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
 832         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
 833         lu_gp = local_lu_gp_mem->lu_gp;
 834         atomic_inc(&lu_gp->lu_gp_ref_cnt);
 835         smp_mb__after_atomic_inc();
 836         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
 837         /*
 838          * For storage objects that are members of the 'default_lu_gp',
 839          * we only do transition on the passed *l_tp_pt_gp, and not
 840          * on all of the matching target port groups IDs in default_lu_gp.
 841          */
 842         if (!(lu_gp->lu_gp_id)) {
 843                 /*
 844                  * core_alua_do_transition_tg_pt() will always return
 845                  * success.
 846                  */
 847                 core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
 848                                         md_buf, new_state, explict);
 849                 atomic_dec(&lu_gp->lu_gp_ref_cnt);
 850                 smp_mb__after_atomic_dec();
 851                 kfree(md_buf);
 852                 return 0;
 853         }
 854         /*
 855          * For all other LU groups aside from 'default_lu_gp', walk all of
 856          * the associated storage objects looking for a matching target port
 857          * group ID from the local target port group.
 858          */
 859         spin_lock(&lu_gp->lu_gp_lock);
 860         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
 861                                 lu_gp_mem_list) {
 862
 863                 dev = lu_gp_mem->lu_gp_mem_dev;
 864                 su_dev = dev->se_sub_dev;
 865                 atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
 866                 smp_mb__after_atomic_inc();
 867                 spin_unlock(&lu_gp->lu_gp_lock);
 868
 869                 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 870                 list_for_each_entry(tg_pt_gp,
 871                                 &T10_ALUA(su_dev)->tg_pt_gps_list,
 872                                 tg_pt_gp_list) {
 873
 874                         if (!(tg_pt_gp->tg_pt_gp_valid_id))
 875                                 continue;
 876                         /*
 877                          * If the target behavior port asymmetric access state
 878                          * is changed for any target port group accessiable via
 879                          * a logical unit within a LU group, the target port
 880                          * behavior group asymmetric access states for the same
 881                          * target port group accessible via other logical units
 882                          * in that LU group will also change.
 883                          */
 884                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
 885                                 continue;
 886
 887                         if (l_tg_pt_gp == tg_pt_gp) {
 888                                 port = l_port;
 889                                 nacl = l_nacl;
 890                         } else {
 891                                 port = NULL;
 892                                 nacl = NULL;
 893                         }
 894                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
 895                         smp_mb__after_atomic_inc();
 896                         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 897                         /*
 898                          * core_alua_do_transition_tg_pt() will always return
 899                          * success.
 900                          */
 901                         core_alua_do_transition_tg_pt(tg_pt_gp, port,
 902                                         nacl, md_buf, new_state, explict);
 903
 904                         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 905                         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
 906                         smp_mb__after_atomic_dec();
 907                 }
 908                 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
 909
 910                 spin_lock(&lu_gp->lu_gp_lock);
 911                 atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
 912                 smp_mb__after_atomic_dec();
 913         }
 914         spin_unlock(&lu_gp->lu_gp_lock);
 915
 916         printk(KERN_INFO "Successfully processed LU Group: %s all ALUA TG PT"
 917                 " Group IDs: %hu %s transition to primary state: %s\n",
 918                 config_item_name(&lu_gp->lu_gp_group.cg_item),
 919                 l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
 920                 core_alua_dump_state(new_state));
 921
 922         atomic_dec(&lu_gp->lu_gp_ref_cnt);
 923         smp_mb__after_atomic_dec();
 924         kfree(md_buf);
 925         return 0;
 926 }
 927
 928 /*
 929  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
 930  */
 931 static int core_alua_update_tpg_secondary_metadata(
 932         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 933         struct se_port *port,
 934         unsigned char *md_buf,
 935         u32 md_buf_len)
 936 {
 937         struct se_portal_group *se_tpg = port->sep_tpg;
 938         char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
 939         int len;
 940
 941         memset(path, 0, ALUA_METADATA_PATH_LEN);
 942         memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
 943
 944         len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
 945                         TPG_TFO(se_tpg)->tpg_get_wwn(se_tpg));
 946
 947         if (TPG_TFO(se_tpg)->tpg_get_tag != NULL)
 948                 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
 949                                 TPG_TFO(se_tpg)->tpg_get_tag(se_tpg));
 950
 951         len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
 952                         "alua_tg_pt_status=0x%02x\n",
 953                         atomic_read(&port->sep_tg_pt_secondary_offline),
 954                         port->sep_tg_pt_secondary_stat);
 955
 956         snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
 957                         TPG_TFO(se_tpg)->get_fabric_name(), wwn,
 958                         port->sep_lun->unpacked_lun);
 959
 960         return core_alua_write_tpg_metadata(path, md_buf, len);
 961 }
 962
 963 static int core_alua_set_tg_pt_secondary_state(
 964         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
 965         struct se_port *port,
 966         int explict,
 967         int offline)
 968 {
 969         struct t10_alua_tg_pt_gp *tg_pt_gp;
 970         unsigned char *md_buf;
 971         u32 md_buf_len;
 972         int trans_delay_msecs;
 973
 974         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 975         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
 976         if (!(tg_pt_gp)) {
 977                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
 978                 printk(KERN_ERR "Unable to complete secondary state"
 979                                 " transition\n");
 980                 return -1;
 981         }
 982         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
 983         /*
 984          * Set the secondary ALUA target port access state to OFFLINE
 985          * or release the previously secondary state for struct se_port
 986          */
 987         if (offline)
 988                 atomic_set(&port->sep_tg_pt_secondary_offline, 1);
 989         else
 990                 atomic_set(&port->sep_tg_pt_secondary_offline, 0);
 991
 992         md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
 993         port->sep_tg_pt_secondary_stat = (explict) ?
 994                         ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
 995                         ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
 996
 997         printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
 998                 " to secondary access state: %s\n", (explict) ? "explict" :
 999                 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1000                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1001
1002         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1003         /*
1004          * Do the optional transition delay after we set the secondary
1005          * ALUA access state.
1006          */
1007         if (trans_delay_msecs != 0)
1008                 msleep_interruptible(trans_delay_msecs);
1009         /*
1010          * See if we need to update the ALUA fabric port metadata for
1011          * secondary state and status
1012          */
1013         if (port->sep_tg_pt_secondary_write_md) {
1014                 md_buf = kzalloc(md_buf_len, GFP_KERNEL);
1015                 if (!(md_buf)) {
1016                         printk(KERN_ERR "Unable to allocate md_buf for"
1017                                 " secondary ALUA access metadata\n");
1018                         return -1;
1019                 }
1020                 mutex_lock(&port->sep_tg_pt_md_mutex);
1021                 core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
1022                                 md_buf, md_buf_len);
1023                 mutex_unlock(&port->sep_tg_pt_md_mutex);
1024
1025                 kfree(md_buf);
1026         }
1027
1028         return 0;
1029 }
1030
1031 struct t10_alua_lu_gp *
1032 core_alua_allocate_lu_gp(const char *name, int def_group)
1033 {
1034         struct t10_alua_lu_gp *lu_gp;
1035
1036         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1037         if (!(lu_gp)) {
1038                 printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp\n");
1039                 return ERR_PTR(-ENOMEM);
1040         }
1041         INIT_LIST_HEAD(&lu_gp->lu_gp_list);
1042         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1043         spin_lock_init(&lu_gp->lu_gp_lock);
1044         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1045
1046         if (def_group) {
1047                 lu_gp->lu_gp_id = se_global->alua_lu_gps_counter++;
1048                 lu_gp->lu_gp_valid_id = 1;
1049                 se_global->alua_lu_gps_count++;
1050         }
1051
1052         return lu_gp;
1053 }
1054
1055 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1056 {
1057         struct t10_alua_lu_gp *lu_gp_tmp;
1058         u16 lu_gp_id_tmp;
1059         /*
1060          * The lu_gp->lu_gp_id may only be set once..
1061          */
1062         if (lu_gp->lu_gp_valid_id) {
1063                 printk(KERN_WARNING "ALUA LU Group already has a valid ID,"
1064                         " ignoring request\n");
1065                 return -1;
1066         }
1067
1068         spin_lock(&se_global->lu_gps_lock);
1069         if (se_global->alua_lu_gps_count == 0x0000ffff) {
1070                 printk(KERN_ERR "Maximum ALUA se_global->alua_lu_gps_count:"
1071                                 " 0x0000ffff reached\n");
1072                 spin_unlock(&se_global->lu_gps_lock);
1073                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1074                 return -1;
1075         }
1076 again:
1077         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1078                                 se_global->alua_lu_gps_counter++;
1079
1080         list_for_each_entry(lu_gp_tmp, &se_global->g_lu_gps_list, lu_gp_list) {
1081                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1082                         if (!(lu_gp_id))
1083                                 goto again;
1084
1085                         printk(KERN_WARNING "ALUA Logical Unit Group ID: %hu"
1086                                 " already exists, ignoring request\n",
1087                                 lu_gp_id);
1088                         spin_unlock(&se_global->lu_gps_lock);
1089                         return -1;
1090                 }
1091         }
1092
1093         lu_gp->lu_gp_id = lu_gp_id_tmp;
1094         lu_gp->lu_gp_valid_id = 1;
1095         list_add_tail(&lu_gp->lu_gp_list, &se_global->g_lu_gps_list);
1096         se_global->alua_lu_gps_count++;
1097         spin_unlock(&se_global->lu_gps_lock);
1098
1099         return 0;
1100 }
1101
1102 static struct t10_alua_lu_gp_member *
1103 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1104 {
1105         struct t10_alua_lu_gp_member *lu_gp_mem;
1106
1107         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1108         if (!(lu_gp_mem)) {
1109                 printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp_member\n");
1110                 return ERR_PTR(-ENOMEM);
1111         }
1112         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1113         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1114         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1115
1116         lu_gp_mem->lu_gp_mem_dev = dev;
1117         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1118
1119         return lu_gp_mem;
1120 }
1121
1122 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1123 {
1124         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1125         /*
1126          * Once we have reached this point, config_item_put() has
1127          * already been called from target_core_alua_drop_lu_gp().
1128          *
1129          * Here, we remove the *lu_gp from the global list so that
1130          * no associations can be made while we are releasing
1131          * struct t10_alua_lu_gp.
1132          */
1133         spin_lock(&se_global->lu_gps_lock);
1134         atomic_set(&lu_gp->lu_gp_shutdown, 1);
1135         list_del(&lu_gp->lu_gp_list);
1136         se_global->alua_lu_gps_count--;
1137         spin_unlock(&se_global->lu_gps_lock);
1138         /*
1139          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1140          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1141          * released with core_alua_put_lu_gp_from_name()
1142          */
1143         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1144                 cpu_relax();
1145         /*
1146          * Release reference to struct t10_alua_lu_gp * from all associated
1147          * struct se_device.
1148          */
1149         spin_lock(&lu_gp->lu_gp_lock);
1150         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1151                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1152                 if (lu_gp_mem->lu_gp_assoc) {
1153                         list_del(&lu_gp_mem->lu_gp_mem_list);
1154                         lu_gp->lu_gp_members--;
1155                         lu_gp_mem->lu_gp_assoc = 0;
1156                 }
1157                 spin_unlock(&lu_gp->lu_gp_lock);
1158                 /*
1159                  *
1160                  * lu_gp_mem is associated with a single
1161                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1162                  * struct se_device is released via core_alua_free_lu_gp_mem().
1163                  *
1164                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1165                  * we want to re-assocate a given lu_gp_mem with default_lu_gp.
1166                  */
1167                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1168                 if (lu_gp != se_global->default_lu_gp)
1169                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1170                                         se_global->default_lu_gp);
1171                 else
1172                         lu_gp_mem->lu_gp = NULL;
1173                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1174
1175                 spin_lock(&lu_gp->lu_gp_lock);
1176         }
1177         spin_unlock(&lu_gp->lu_gp_lock);
1178
1179         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1180 }
1181
1182 void core_alua_free_lu_gp_mem(struct se_device *dev)
1183 {
1184         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1185         struct t10_alua *alua = T10_ALUA(su_dev);
1186         struct t10_alua_lu_gp *lu_gp;
1187         struct t10_alua_lu_gp_member *lu_gp_mem;
1188
1189         if (alua->alua_type != SPC3_ALUA_EMULATED)
1190                 return;
1191
1192         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1193         if (!(lu_gp_mem))
1194                 return;
1195
1196         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1197                 cpu_relax();
1198
1199         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1200         lu_gp = lu_gp_mem->lu_gp;
1201         if ((lu_gp)) {
1202                 spin_lock(&lu_gp->lu_gp_lock);
1203                 if (lu_gp_mem->lu_gp_assoc) {
1204                         list_del(&lu_gp_mem->lu_gp_mem_list);
1205                         lu_gp->lu_gp_members--;
1206                         lu_gp_mem->lu_gp_assoc = 0;
1207                 }
1208                 spin_unlock(&lu_gp->lu_gp_lock);
1209                 lu_gp_mem->lu_gp = NULL;
1210         }
1211         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1212
1213         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1214 }
1215
1216 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1217 {
1218         struct t10_alua_lu_gp *lu_gp;
1219         struct config_item *ci;
1220
1221         spin_lock(&se_global->lu_gps_lock);
1222         list_for_each_entry(lu_gp, &se_global->g_lu_gps_list, lu_gp_list) {
1223                 if (!(lu_gp->lu_gp_valid_id))
1224                         continue;
1225                 ci = &lu_gp->lu_gp_group.cg_item;
1226                 if (!(strcmp(config_item_name(ci), name))) {
1227                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1228                         spin_unlock(&se_global->lu_gps_lock);
1229                         return lu_gp;
1230                 }
1231         }
1232         spin_unlock(&se_global->lu_gps_lock);
1233
1234         return NULL;
1235 }
1236
1237 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1238 {
1239         spin_lock(&se_global->lu_gps_lock);
1240         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1241         spin_unlock(&se_global->lu_gps_lock);
1242 }
1243
1244 /*
1245  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1246  */
1247 void __core_alua_attach_lu_gp_mem(
1248         struct t10_alua_lu_gp_member *lu_gp_mem,
1249         struct t10_alua_lu_gp *lu_gp)
1250 {
1251         spin_lock(&lu_gp->lu_gp_lock);
1252         lu_gp_mem->lu_gp = lu_gp;
1253         lu_gp_mem->lu_gp_assoc = 1;
1254         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1255         lu_gp->lu_gp_members++;
1256         spin_unlock(&lu_gp->lu_gp_lock);
1257 }
1258
1259 /*
1260  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1261  */
1262 void __core_alua_drop_lu_gp_mem(
1263         struct t10_alua_lu_gp_member *lu_gp_mem,
1264         struct t10_alua_lu_gp *lu_gp)
1265 {
1266         spin_lock(&lu_gp->lu_gp_lock);
1267         list_del(&lu_gp_mem->lu_gp_mem_list);
1268         lu_gp_mem->lu_gp = NULL;
1269         lu_gp_mem->lu_gp_assoc = 0;
1270         lu_gp->lu_gp_members--;
1271         spin_unlock(&lu_gp->lu_gp_lock);
1272 }
1273
1274 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
1275         struct se_subsystem_dev *su_dev,
1276         const char *name,
1277         int def_group)
1278 {
1279         struct t10_alua_tg_pt_gp *tg_pt_gp;
1280
1281         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1282         if (!(tg_pt_gp)) {
1283                 printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp\n");
1284                 return NULL;
1285         }
1286         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1287         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1288         mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1289         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1290         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1291         tg_pt_gp->tg_pt_gp_su_dev = su_dev;
1292         tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
1293         atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1294                 ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
1295         /*
1296          * Enable both explict and implict ALUA support by default
1297          */
1298         tg_pt_gp->tg_pt_gp_alua_access_type =
1299                         TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
1300         /*
1301          * Set the default Active/NonOptimized Delay in milliseconds
1302          */
1303         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1304         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1305
1306         if (def_group) {
1307                 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1308                 tg_pt_gp->tg_pt_gp_id =
1309                                 T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
1310                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1311                 T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
1312                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1313                               &T10_ALUA(su_dev)->tg_pt_gps_list);
1314                 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1315         }
1316
1317         return tg_pt_gp;
1318 }
1319
1320 int core_alua_set_tg_pt_gp_id(
1321         struct t10_alua_tg_pt_gp *tg_pt_gp,
1322         u16 tg_pt_gp_id)
1323 {
1324         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1325         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1326         u16 tg_pt_gp_id_tmp;
1327         /*
1328          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1329          */
1330         if (tg_pt_gp->tg_pt_gp_valid_id) {
1331                 printk(KERN_WARNING "ALUA TG PT Group already has a valid ID,"
1332                         " ignoring request\n");
1333                 return -1;
1334         }
1335
1336         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1337         if (T10_ALUA(su_dev)->alua_tg_pt_gps_count == 0x0000ffff) {
1338                 printk(KERN_ERR "Maximum ALUA alua_tg_pt_gps_count:"
1339                         " 0x0000ffff reached\n");
1340                 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1341                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1342                 return -1;
1343         }
1344 again:
1345         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1346                         T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
1347
1348         list_for_each_entry(tg_pt_gp_tmp, &T10_ALUA(su_dev)->tg_pt_gps_list,
1349                         tg_pt_gp_list) {
1350                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1351                         if (!(tg_pt_gp_id))
1352                                 goto again;
1353
1354                         printk(KERN_ERR "ALUA Target Port Group ID: %hu already"
1355                                 " exists, ignoring request\n", tg_pt_gp_id);
1356                         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1357                         return -1;
1358                 }
1359         }
1360
1361         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1362         tg_pt_gp->tg_pt_gp_valid_id = 1;
1363         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1364                         &T10_ALUA(su_dev)->tg_pt_gps_list);
1365         T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
1366         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1367
1368         return 0;
1369 }
1370
1371 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1372         struct se_port *port)
1373 {
1374         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1375
1376         tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1377                                 GFP_KERNEL);
1378         if (!(tg_pt_gp_mem)) {
1379                 printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1380                 return ERR_PTR(-ENOMEM);
1381         }
1382         INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1383         spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1384         atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1385
1386         tg_pt_gp_mem->tg_pt = port;
1387         port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1388         atomic_set(&port->sep_tg_pt_gp_active, 1);
1389
1390         return tg_pt_gp_mem;
1391 }
1392
1393 void core_alua_free_tg_pt_gp(
1394         struct t10_alua_tg_pt_gp *tg_pt_gp)
1395 {
1396         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1397         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1398         /*
1399          * Once we have reached this point, config_item_put() has already
1400          * been called from target_core_alua_drop_tg_pt_gp().
1401          *
1402          * Here we remove *tg_pt_gp from the global list so that
1403          * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
1404          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1405          */
1406         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1407         list_del(&tg_pt_gp->tg_pt_gp_list);
1408         T10_ALUA(su_dev)->alua_tg_pt_gps_counter--;
1409         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1410         /*
1411          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1412          * core_alua_get_tg_pt_gp_by_name() in
1413          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1414          * to be released with core_alua_put_tg_pt_gp_from_name().
1415          */
1416         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1417                 cpu_relax();
1418         /*
1419          * Release reference to struct t10_alua_tg_pt_gp from all associated
1420          * struct se_port.
1421          */
1422         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1423         list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1424                         &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1425                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1426                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1427                         tg_pt_gp->tg_pt_gp_members--;
1428                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1429                 }
1430                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1431                 /*
1432                  * tg_pt_gp_mem is associated with a single
1433                  * se_port->sep_alua_tg_pt_gp_mem, and is released via
1434                  * core_alua_free_tg_pt_gp_mem().
1435                  *
1436                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1437                  * assume we want to re-assocate a given tg_pt_gp_mem with
1438                  * default_tg_pt_gp.
1439                  */
1440                 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1441                 if (tg_pt_gp != T10_ALUA(su_dev)->default_tg_pt_gp) {
1442                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1443                                         T10_ALUA(su_dev)->default_tg_pt_gp);
1444                 } else
1445                         tg_pt_gp_mem->tg_pt_gp = NULL;
1446                 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1447
1448                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1449         }
1450         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1451
1452         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1453 }
1454
1455 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1456 {
1457         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1458         struct t10_alua *alua = T10_ALUA(su_dev);
1459         struct t10_alua_tg_pt_gp *tg_pt_gp;
1460         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1461
1462         if (alua->alua_type != SPC3_ALUA_EMULATED)
1463                 return;
1464
1465         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1466         if (!(tg_pt_gp_mem))
1467                 return;
1468
1469         while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1470                 cpu_relax();
1471
1472         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1473         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1474         if ((tg_pt_gp)) {
1475                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1476                 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1477                         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1478                         tg_pt_gp->tg_pt_gp_members--;
1479                         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1480                 }
1481                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1482                 tg_pt_gp_mem->tg_pt_gp = NULL;
1483         }
1484         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1485
1486         kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1487 }
1488
1489 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1490         struct se_subsystem_dev *su_dev,
1491         const char *name)
1492 {
1493         struct t10_alua_tg_pt_gp *tg_pt_gp;
1494         struct config_item *ci;
1495
1496         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1497         list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
1498                         tg_pt_gp_list) {
1499                 if (!(tg_pt_gp->tg_pt_gp_valid_id))
1500                         continue;
1501                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1502                 if (!(strcmp(config_item_name(ci), name))) {
1503                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1504                         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1505                         return tg_pt_gp;
1506                 }
1507         }
1508         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1509
1510         return NULL;
1511 }
1512
1513 static void core_alua_put_tg_pt_gp_from_name(
1514         struct t10_alua_tg_pt_gp *tg_pt_gp)
1515 {
1516         struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1517
1518         spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1519         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1520         spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1521 }
1522
1523 /*
1524  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1525  */
1526 void __core_alua_attach_tg_pt_gp_mem(
1527         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1528         struct t10_alua_tg_pt_gp *tg_pt_gp)
1529 {
1530         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1531         tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1532         tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1533         list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1534                         &tg_pt_gp->tg_pt_gp_mem_list);
1535         tg_pt_gp->tg_pt_gp_members++;
1536         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1537 }
1538
1539 /*
1540  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1541  */
1542 static void __core_alua_drop_tg_pt_gp_mem(
1543         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1544         struct t10_alua_tg_pt_gp *tg_pt_gp)
1545 {
1546         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1547         list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1548         tg_pt_gp_mem->tg_pt_gp = NULL;
1549         tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1550         tg_pt_gp->tg_pt_gp_members--;
1551         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1552 }
1553
1554 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1555 {
1556         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1557         struct config_item *tg_pt_ci;
1558         struct t10_alua *alua = T10_ALUA(su_dev);
1559         struct t10_alua_tg_pt_gp *tg_pt_gp;
1560         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1561         ssize_t len = 0;
1562
1563         if (alua->alua_type != SPC3_ALUA_EMULATED)
1564                 return len;
1565
1566         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1567         if (!(tg_pt_gp_mem))
1568                 return len;
1569
1570         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1571         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1572         if ((tg_pt_gp)) {
1573                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1574                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1575                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1576                         "Primary Access Status: %s\nTG Port Secondary Access"
1577                         " State: %s\nTG Port Secondary Access Status: %s\n",
1578                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1579                         core_alua_dump_state(atomic_read(
1580                                         &tg_pt_gp->tg_pt_gp_alua_access_state)),
1581                         core_alua_dump_status(
1582                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1583                         (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
1584                         "Offline" : "None",
1585                         core_alua_dump_status(port->sep_tg_pt_secondary_stat));
1586         }
1587         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1588
1589         return len;
1590 }
1591
1592 ssize_t core_alua_store_tg_pt_gp_info(
1593         struct se_port *port,
1594         const char *page,
1595         size_t count)
1596 {
1597         struct se_portal_group *tpg;
1598         struct se_lun *lun;
1599         struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1600         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1601         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1602         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1603         int move = 0;
1604
1605         tpg = port->sep_tpg;
1606         lun = port->sep_lun;
1607
1608         if (T10_ALUA(su_dev)->alua_type != SPC3_ALUA_EMULATED) {
1609                 printk(KERN_WARNING "SPC3_ALUA_EMULATED not enabled for"
1610                         " %s/tpgt_%hu/%s\n", TPG_TFO(tpg)->tpg_get_wwn(tpg),
1611                         TPG_TFO(tpg)->tpg_get_tag(tpg),
1612                         config_item_name(&lun->lun_group.cg_item));
1613                 return -EINVAL;
1614         }
1615
1616         if (count > TG_PT_GROUP_NAME_BUF) {
1617                 printk(KERN_ERR "ALUA Target Port Group alias too large!\n");
1618                 return -EINVAL;
1619         }
1620         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1621         memcpy(buf, page, count);
1622         /*
1623          * Any ALUA target port group alias besides "NULL" means we will be
1624          * making a new group association.
1625          */
1626         if (strcmp(strstrip(buf), "NULL")) {
1627                 /*
1628                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1629                  * struct t10_alua_tg_pt_gp.  This reference is released with
1630                  * core_alua_put_tg_pt_gp_from_name() below.
1631                  */
1632                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
1633                                         strstrip(buf));
1634                 if (!(tg_pt_gp_new))
1635                         return -ENODEV;
1636         }
1637         tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1638         if (!(tg_pt_gp_mem)) {
1639                 if (tg_pt_gp_new)
1640                         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1641                 printk(KERN_ERR "NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
1642                 return -EINVAL;
1643         }
1644
1645         spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1646         tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1647         if ((tg_pt_gp)) {
1648                 /*
1649                  * Clearing an existing tg_pt_gp association, and replacing
1650                  * with the default_tg_pt_gp.
1651                  */
1652                 if (!(tg_pt_gp_new)) {
1653                         printk(KERN_INFO "Target_Core_ConfigFS: Moving"
1654                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1655                                 " alua/%s, ID: %hu back to"
1656                                 " default_tg_pt_gp\n",
1657                                 TPG_TFO(tpg)->tpg_get_wwn(tpg),
1658                                 TPG_TFO(tpg)->tpg_get_tag(tpg),
1659                                 config_item_name(&lun->lun_group.cg_item),
1660                                 config_item_name(
1661                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1662                                 tg_pt_gp->tg_pt_gp_id);
1663
1664                         __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1665                         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1666                                         T10_ALUA(su_dev)->default_tg_pt_gp);
1667                         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1668
1669                         return count;
1670                 }
1671                 /*
1672                  * Removing existing association of tg_pt_gp_mem with tg_pt_gp
1673                  */
1674                 __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1675                 move = 1;
1676         }
1677         /*
1678          * Associate tg_pt_gp_mem with tg_pt_gp_new.
1679          */
1680         __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
1681         spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1682         printk(KERN_INFO "Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1683                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1684                 "Moving" : "Adding", TPG_TFO(tpg)->tpg_get_wwn(tpg),
1685                 TPG_TFO(tpg)->tpg_get_tag(tpg),
1686                 config_item_name(&lun->lun_group.cg_item),
1687                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1688                 tg_pt_gp_new->tg_pt_gp_id);
1689
1690         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1691         return count;
1692 }
1693
1694 ssize_t core_alua_show_access_type(
1695         struct t10_alua_tg_pt_gp *tg_pt_gp,
1696         char *page)
1697 {
1698         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
1699             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
1700                 return sprintf(page, "Implict and Explict\n");
1701         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
1702                 return sprintf(page, "Implict\n");
1703         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
1704                 return sprintf(page, "Explict\n");
1705         else
1706                 return sprintf(page, "None\n");
1707 }
1708
1709 ssize_t core_alua_store_access_type(
1710         struct t10_alua_tg_pt_gp *tg_pt_gp,
1711         const char *page,
1712         size_t count)
1713 {
1714         unsigned long tmp;
1715         int ret;
1716
1717         ret = strict_strtoul(page, 0, &tmp);
1718         if (ret < 0) {
1719                 printk(KERN_ERR "Unable to extract alua_access_type\n");
1720                 return -EINVAL;
1721         }
1722         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
1723                 printk(KERN_ERR "Illegal value for alua_access_type:"
1724                                 " %lu\n", tmp);
1725                 return -EINVAL;
1726         }
1727         if (tmp == 3)
1728                 tg_pt_gp->tg_pt_gp_alua_access_type =
1729                         TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
1730         else if (tmp == 2)
1731                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
1732         else if (tmp == 1)
1733                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
1734         else
1735                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
1736
1737         return count;
1738 }
1739
1740 ssize_t core_alua_show_nonop_delay_msecs(
1741         struct t10_alua_tg_pt_gp *tg_pt_gp,
1742         char *page)
1743 {
1744         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
1745 }
1746
1747 ssize_t core_alua_store_nonop_delay_msecs(
1748         struct t10_alua_tg_pt_gp *tg_pt_gp,
1749         const char *page,
1750         size_t count)
1751 {
1752         unsigned long tmp;
1753         int ret;
1754
1755         ret = strict_strtoul(page, 0, &tmp);
1756         if (ret < 0) {
1757                 printk(KERN_ERR "Unable to extract nonop_delay_msecs\n");
1758                 return -EINVAL;
1759         }
1760         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
1761                 printk(KERN_ERR "Passed nonop_delay_msecs: %lu, exceeds"
1762                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
1763                         ALUA_MAX_NONOP_DELAY_MSECS);
1764                 return -EINVAL;
1765         }
1766         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
1767
1768         return count;
1769 }
1770
1771 ssize_t core_alua_show_trans_delay_msecs(
1772         struct t10_alua_tg_pt_gp *tg_pt_gp,
1773         char *page)
1774 {
1775         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1776 }
1777
1778 ssize_t core_alua_store_trans_delay_msecs(
1779         struct t10_alua_tg_pt_gp *tg_pt_gp,
1780         const char *page,
1781         size_t count)
1782 {
1783         unsigned long tmp;
1784         int ret;
1785
1786         ret = strict_strtoul(page, 0, &tmp);
1787         if (ret < 0) {
1788                 printk(KERN_ERR "Unable to extract trans_delay_msecs\n");
1789                 return -EINVAL;
1790         }
1791         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
1792                 printk(KERN_ERR "Passed trans_delay_msecs: %lu, exceeds"
1793                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
1794                         ALUA_MAX_TRANS_DELAY_MSECS);
1795                 return -EINVAL;
1796         }
1797         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
1798
1799         return count;
1800 }
1801
1802 ssize_t core_alua_show_preferred_bit(
1803         struct t10_alua_tg_pt_gp *tg_pt_gp,
1804         char *page)
1805 {
1806         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
1807 }
1808
1809 ssize_t core_alua_store_preferred_bit(
1810         struct t10_alua_tg_pt_gp *tg_pt_gp,
1811         const char *page,
1812         size_t count)
1813 {
1814         unsigned long tmp;
1815         int ret;
1816
1817         ret = strict_strtoul(page, 0, &tmp);
1818         if (ret < 0) {
1819                 printk(KERN_ERR "Unable to extract preferred ALUA value\n");
1820                 return -EINVAL;
1821         }
1822         if ((tmp != 0) && (tmp != 1)) {
1823                 printk(KERN_ERR "Illegal value for preferred ALUA: %lu\n", tmp);
1824                 return -EINVAL;
1825         }
1826         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
1827
1828         return count;
1829 }
1830
1831 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
1832 {
1833         if (!(lun->lun_sep))
1834                 return -ENODEV;
1835
1836         return sprintf(page, "%d\n",
1837                 atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
1838 }
1839
1840 ssize_t core_alua_store_offline_bit(
1841         struct se_lun *lun,
1842         const char *page,
1843         size_t count)
1844 {
1845         struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1846         unsigned long tmp;
1847         int ret;
1848
1849         if (!(lun->lun_sep))
1850                 return -ENODEV;
1851
1852         ret = strict_strtoul(page, 0, &tmp);
1853         if (ret < 0) {
1854                 printk(KERN_ERR "Unable to extract alua_tg_pt_offline value\n");
1855                 return -EINVAL;
1856         }
1857         if ((tmp != 0) && (tmp != 1)) {
1858                 printk(KERN_ERR "Illegal value for alua_tg_pt_offline: %lu\n",
1859                                 tmp);
1860                 return -EINVAL;
1861         }
1862         tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
1863         if (!(tg_pt_gp_mem)) {
1864                 printk(KERN_ERR "Unable to locate *tg_pt_gp_mem\n");
1865                 return -EINVAL;
1866         }
1867
1868         ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
1869                         lun->lun_sep, 0, (int)tmp);
1870         if (ret < 0)
1871                 return -EINVAL;
1872
1873         return count;
1874 }
1875
1876 ssize_t core_alua_show_secondary_status(
1877         struct se_lun *lun,
1878         char *page)
1879 {
1880         return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
1881 }
1882
1883 ssize_t core_alua_store_secondary_status(
1884         struct se_lun *lun,
1885         const char *page,
1886         size_t count)
1887 {
1888         unsigned long tmp;
1889         int ret;
1890
1891         ret = strict_strtoul(page, 0, &tmp);
1892         if (ret < 0) {
1893                 printk(KERN_ERR "Unable to extract alua_tg_pt_status\n");
1894                 return -EINVAL;
1895         }
1896         if ((tmp != ALUA_STATUS_NONE) &&
1897             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
1898             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
1899                 printk(KERN_ERR "Illegal value for alua_tg_pt_status: %lu\n",
1900                                 tmp);
1901                 return -EINVAL;
1902         }
1903         lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
1904
1905         return count;
1906 }
1907
1908 ssize_t core_alua_show_secondary_write_metadata(
1909         struct se_lun *lun,
1910         char *page)
1911 {
1912         return sprintf(page, "%d\n",
1913                         lun->lun_sep->sep_tg_pt_secondary_write_md);
1914 }
1915
1916 ssize_t core_alua_store_secondary_write_metadata(
1917         struct se_lun *lun,
1918         const char *page,
1919         size_t count)
1920 {
1921         unsigned long tmp;
1922         int ret;
1923
1924         ret = strict_strtoul(page, 0, &tmp);
1925         if (ret < 0) {
1926                 printk(KERN_ERR "Unable to extract alua_tg_pt_write_md\n");
1927                 return -EINVAL;
1928         }
1929         if ((tmp != 0) && (tmp != 1)) {
1930                 printk(KERN_ERR "Illegal value for alua_tg_pt_write_md:"
1931                                 " %lu\n", tmp);
1932                 return -EINVAL;
1933         }
1934         lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
1935
1936         return count;
1937 }
1938
1939 int core_setup_alua(struct se_device *dev, int force_pt)
1940 {
1941         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1942         struct t10_alua *alua = T10_ALUA(su_dev);
1943         struct t10_alua_lu_gp_member *lu_gp_mem;
1944         /*
1945          * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
1946          * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
1947          * cause a problem because libata and some SATA RAID HBAs appear
1948          * under Linux/SCSI, but emulate SCSI logic themselves.
1949          */
1950         if (((TRANSPORT(dev)->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
1951             !(DEV_ATTRIB(dev)->emulate_alua)) || force_pt) {
1952                 alua->alua_type = SPC_ALUA_PASSTHROUGH;
1953                 alua->alua_state_check = &core_alua_state_check_nop;
1954                 printk(KERN_INFO "%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
1955                         " emulation\n", TRANSPORT(dev)->name);
1956                 return 0;
1957         }
1958         /*
1959          * If SPC-3 or above is reported by real or emulated struct se_device,
1960          * use emulated ALUA.
1961          */
1962         if (TRANSPORT(dev)->get_device_rev(dev) >= SCSI_3) {
1963                 printk(KERN_INFO "%s: Enabling ALUA Emulation for SPC-3"
1964                         " device\n", TRANSPORT(dev)->name);
1965                 /*
1966                  * Associate this struct se_device with the default ALUA
1967                  * LUN Group.
1968                  */
1969                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
1970                 if (IS_ERR(lu_gp_mem) || !lu_gp_mem)
1971                         return -1;
1972
1973                 alua->alua_type = SPC3_ALUA_EMULATED;
1974                 alua->alua_state_check = &core_alua_state_check;
1975                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1976                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
1977                                 se_global->default_lu_gp);
1978                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1979
1980                 printk(KERN_INFO "%s: Adding to default ALUA LU Group:"
1981                         " core/alua/lu_gps/default_lu_gp\n",
1982                         TRANSPORT(dev)->name);
1983         } else {
1984                 alua->alua_type = SPC2_ALUA_DISABLED;
1985                 alua->alua_state_check = &core_alua_state_check_nop;
1986                 printk(KERN_INFO "%s: Disabling ALUA Emulation for SPC-2"
1987                         " device\n", TRANSPORT(dev)->name);
1988         }
1989
1990         return 0;
1991 }