root/drivers/target/target_core_pr.c

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DEFINITIONS

This source file includes following definitions.
  1. core_pr_dump_initiator_port
  2. is_reservation_holder
  3. target_scsi2_reservation_check
  4. target_check_scsi2_reservation_conflict
  5. target_release_reservation
  6. target_scsi2_reservation_release
  7. target_scsi2_reservation_reserve
  8. core_scsi3_pr_seq_non_holder
  9. target_scsi3_pr_reservation_check
  10. core_scsi3_pr_generation
  11. __core_scsi3_do_alloc_registration
  12. __core_scsi3_alloc_registration
  13. core_scsi3_alloc_aptpl_registration
  14. core_scsi3_aptpl_reserve
  15. __core_scsi3_check_aptpl_registration
  16. core_scsi3_check_aptpl_registration
  17. __core_scsi3_dump_registration
  18. __core_scsi3_add_registration
  19. core_scsi3_alloc_registration
  20. __core_scsi3_locate_pr_reg
  21. core_scsi3_locate_pr_reg
  22. core_scsi3_put_pr_reg
  23. core_scsi3_check_implicit_release
  24. __core_scsi3_free_registration
  25. core_scsi3_free_pr_reg_from_nacl
  26. core_scsi3_free_all_registrations
  27. core_scsi3_tpg_depend_item
  28. core_scsi3_tpg_undepend_item
  29. core_scsi3_nodeacl_depend_item
  30. core_scsi3_nodeacl_undepend_item
  31. core_scsi3_lunacl_depend_item
  32. core_scsi3_lunacl_undepend_item
  33. core_scsi3_decode_spec_i_port
  34. core_scsi3_update_aptpl_buf
  35. __core_scsi3_write_aptpl_to_file
  36. core_scsi3_update_and_write_aptpl
  37. core_scsi3_emulate_pro_register
  38. core_scsi3_pr_dump_type
  39. core_scsi3_pro_reserve
  40. core_scsi3_emulate_pro_reserve
  41. __core_scsi3_complete_pro_release
  42. core_scsi3_emulate_pro_release
  43. core_scsi3_emulate_pro_clear
  44. __core_scsi3_complete_pro_preempt
  45. core_scsi3_release_preempt_and_abort
  46. core_scsi3_pro_preempt
  47. core_scsi3_emulate_pro_preempt
  48. core_scsi3_emulate_pro_register_and_move
  49. target_scsi3_emulate_pr_out
  50. core_scsi3_pri_read_keys
  51. core_scsi3_pri_read_reservation
  52. core_scsi3_pri_report_capabilities
  53. core_scsi3_pri_read_full_status
  54. target_scsi3_emulate_pr_in
  55. target_check_reservation

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * Filename:  target_core_pr.c
   4  *
   5  * This file contains SPC-3 compliant persistent reservations and
   6  * legacy SPC-2 reservations with compatible reservation handling (CRH=1)
   7  *
   8  * (c) Copyright 2009-2013 Datera, Inc.
   9  *
  10  * Nicholas A. Bellinger <nab@kernel.org>
  11  *
  12  ******************************************************************************/
  13 
  14 #include <linux/slab.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/list.h>
  17 #include <linux/vmalloc.h>
  18 #include <linux/file.h>
  19 #include <linux/fcntl.h>
  20 #include <linux/fs.h>
  21 #include <scsi/scsi_proto.h>
  22 #include <asm/unaligned.h>
  23 
  24 #include <target/target_core_base.h>
  25 #include <target/target_core_backend.h>
  26 #include <target/target_core_fabric.h>
  27 
  28 #include "target_core_internal.h"
  29 #include "target_core_pr.h"
  30 #include "target_core_ua.h"
  31 
  32 /*
  33  * Used for Specify Initiator Ports Capable Bit (SPEC_I_PT)
  34  */
  35 struct pr_transport_id_holder {
  36         struct t10_pr_registration *dest_pr_reg;
  37         struct se_portal_group *dest_tpg;
  38         struct se_node_acl *dest_node_acl;
  39         struct se_dev_entry *dest_se_deve;
  40         struct list_head dest_list;
  41 };
  42 
  43 void core_pr_dump_initiator_port(
  44         struct t10_pr_registration *pr_reg,
  45         char *buf,
  46         u32 size)
  47 {
  48         if (!pr_reg->isid_present_at_reg) {
  49                 buf[0] = '\0';
  50                 return;
  51         }
  52 
  53         snprintf(buf, size, ",i,0x%s", pr_reg->pr_reg_isid);
  54 }
  55 
  56 enum register_type {
  57         REGISTER,
  58         REGISTER_AND_IGNORE_EXISTING_KEY,
  59         REGISTER_AND_MOVE,
  60 };
  61 
  62 enum preempt_type {
  63         PREEMPT,
  64         PREEMPT_AND_ABORT,
  65 };
  66 
  67 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
  68                                               struct t10_pr_registration *, int, int);
  69 
  70 static int is_reservation_holder(
  71         struct t10_pr_registration *pr_res_holder,
  72         struct t10_pr_registration *pr_reg)
  73 {
  74         int pr_res_type;
  75 
  76         if (pr_res_holder) {
  77                 pr_res_type = pr_res_holder->pr_res_type;
  78 
  79                 return pr_res_holder == pr_reg ||
  80                        pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
  81                        pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG;
  82         }
  83         return 0;
  84 }
  85 
  86 static sense_reason_t
  87 target_scsi2_reservation_check(struct se_cmd *cmd)
  88 {
  89         struct se_device *dev = cmd->se_dev;
  90         struct se_session *sess = cmd->se_sess;
  91 
  92         switch (cmd->t_task_cdb[0]) {
  93         case INQUIRY:
  94         case RELEASE:
  95         case RELEASE_10:
  96                 return 0;
  97         default:
  98                 break;
  99         }
 100 
 101         if (!dev->reservation_holder || !sess)
 102                 return 0;
 103 
 104         if (dev->reservation_holder->se_node_acl != sess->se_node_acl)
 105                 return TCM_RESERVATION_CONFLICT;
 106 
 107         if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
 108                 if (dev->dev_res_bin_isid != sess->sess_bin_isid)
 109                         return TCM_RESERVATION_CONFLICT;
 110         }
 111 
 112         return 0;
 113 }
 114 
 115 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
 116                                         struct se_node_acl *, struct se_session *);
 117 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
 118 
 119 static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
 120 {
 121         struct se_session *se_sess = cmd->se_sess;
 122         struct se_device *dev = cmd->se_dev;
 123         struct t10_pr_registration *pr_reg;
 124         struct t10_reservation *pr_tmpl = &dev->t10_pr;
 125         int conflict = 0;
 126 
 127         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
 128                         se_sess);
 129         if (pr_reg) {
 130                 /*
 131                  * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
 132                  * behavior
 133                  *
 134                  * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
 135                  * status, but no reservation shall be established and the
 136                  * persistent reservation shall not be changed, if the command
 137                  * is received from a) and b) below.
 138                  *
 139                  * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
 140                  * status, but the persistent reservation shall not be released,
 141                  * if the command is received from a) and b)
 142                  *
 143                  * a) An I_T nexus that is a persistent reservation holder; or
 144                  * b) An I_T nexus that is registered if a registrants only or
 145                  *    all registrants type persistent reservation is present.
 146                  *
 147                  * In all other cases, a RESERVE(6) command, RESERVE(10) command,
 148                  * RELEASE(6) command, or RELEASE(10) command shall be processed
 149                  * as defined in SPC-2.
 150                  */
 151                 if (pr_reg->pr_res_holder) {
 152                         core_scsi3_put_pr_reg(pr_reg);
 153                         return 1;
 154                 }
 155                 if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
 156                     (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
 157                     (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
 158                     (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
 159                         core_scsi3_put_pr_reg(pr_reg);
 160                         return 1;
 161                 }
 162                 core_scsi3_put_pr_reg(pr_reg);
 163                 conflict = 1;
 164         } else {
 165                 /*
 166                  * Following spc2r20 5.5.1 Reservations overview:
 167                  *
 168                  * If a logical unit has executed a PERSISTENT RESERVE OUT
 169                  * command with the REGISTER or the REGISTER AND IGNORE
 170                  * EXISTING KEY service action and is still registered by any
 171                  * initiator, all RESERVE commands and all RELEASE commands
 172                  * regardless of initiator shall conflict and shall terminate
 173                  * with a RESERVATION CONFLICT status.
 174                  */
 175                 spin_lock(&pr_tmpl->registration_lock);
 176                 conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
 177                 spin_unlock(&pr_tmpl->registration_lock);
 178         }
 179 
 180         if (conflict) {
 181                 pr_err("Received legacy SPC-2 RESERVE/RELEASE"
 182                         " while active SPC-3 registrations exist,"
 183                         " returning RESERVATION_CONFLICT\n");
 184                 return -EBUSY;
 185         }
 186 
 187         return 0;
 188 }
 189 
 190 void target_release_reservation(struct se_device *dev)
 191 {
 192         dev->reservation_holder = NULL;
 193         dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
 194         if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
 195                 dev->dev_res_bin_isid = 0;
 196                 dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS_WITH_ISID;
 197         }
 198 }
 199 
 200 sense_reason_t
 201 target_scsi2_reservation_release(struct se_cmd *cmd)
 202 {
 203         struct se_device *dev = cmd->se_dev;
 204         struct se_session *sess = cmd->se_sess;
 205         struct se_portal_group *tpg;
 206         int rc;
 207 
 208         if (!sess || !sess->se_tpg)
 209                 goto out;
 210         rc = target_check_scsi2_reservation_conflict(cmd);
 211         if (rc == 1)
 212                 goto out;
 213         if (rc < 0)
 214                 return TCM_RESERVATION_CONFLICT;
 215 
 216         spin_lock(&dev->dev_reservation_lock);
 217         if (!dev->reservation_holder || !sess)
 218                 goto out_unlock;
 219 
 220         if (dev->reservation_holder->se_node_acl != sess->se_node_acl)
 221                 goto out_unlock;
 222 
 223         if (dev->dev_res_bin_isid != sess->sess_bin_isid)
 224                 goto out_unlock;
 225 
 226         target_release_reservation(dev);
 227         tpg = sess->se_tpg;
 228         pr_debug("SCSI-2 Released reservation for %s LUN: %llu ->"
 229                 " MAPPED LUN: %llu for %s\n",
 230                 tpg->se_tpg_tfo->fabric_name,
 231                 cmd->se_lun->unpacked_lun, cmd->orig_fe_lun,
 232                 sess->se_node_acl->initiatorname);
 233 
 234 out_unlock:
 235         spin_unlock(&dev->dev_reservation_lock);
 236 out:
 237         target_complete_cmd(cmd, GOOD);
 238         return 0;
 239 }
 240 
 241 sense_reason_t
 242 target_scsi2_reservation_reserve(struct se_cmd *cmd)
 243 {
 244         struct se_device *dev = cmd->se_dev;
 245         struct se_session *sess = cmd->se_sess;
 246         struct se_portal_group *tpg;
 247         sense_reason_t ret = 0;
 248         int rc;
 249 
 250         if ((cmd->t_task_cdb[1] & 0x01) &&
 251             (cmd->t_task_cdb[1] & 0x02)) {
 252                 pr_err("LongIO and Obsolete Bits set, returning ILLEGAL_REQUEST\n");
 253                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 254         }
 255         /*
 256          * This is currently the case for target_core_mod passthrough struct se_cmd
 257          * ops
 258          */
 259         if (!sess || !sess->se_tpg)
 260                 goto out;
 261         rc = target_check_scsi2_reservation_conflict(cmd);
 262         if (rc == 1)
 263                 goto out;
 264 
 265         if (rc < 0)
 266                 return TCM_RESERVATION_CONFLICT;
 267 
 268         tpg = sess->se_tpg;
 269         spin_lock(&dev->dev_reservation_lock);
 270         if (dev->reservation_holder &&
 271             dev->reservation_holder->se_node_acl != sess->se_node_acl) {
 272                 pr_err("SCSI-2 RESERVATION CONFLIFT for %s fabric\n",
 273                         tpg->se_tpg_tfo->fabric_name);
 274                 pr_err("Original reserver LUN: %llu %s\n",
 275                         cmd->se_lun->unpacked_lun,
 276                         dev->reservation_holder->se_node_acl->initiatorname);
 277                 pr_err("Current attempt - LUN: %llu -> MAPPED LUN: %llu"
 278                         " from %s \n", cmd->se_lun->unpacked_lun,
 279                         cmd->orig_fe_lun,
 280                         sess->se_node_acl->initiatorname);
 281                 ret = TCM_RESERVATION_CONFLICT;
 282                 goto out_unlock;
 283         }
 284 
 285         dev->reservation_holder = sess;
 286         dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS;
 287         if (sess->sess_bin_isid != 0) {
 288                 dev->dev_res_bin_isid = sess->sess_bin_isid;
 289                 dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS_WITH_ISID;
 290         }
 291         pr_debug("SCSI-2 Reserved %s LUN: %llu -> MAPPED LUN: %llu"
 292                 " for %s\n", tpg->se_tpg_tfo->fabric_name,
 293                 cmd->se_lun->unpacked_lun, cmd->orig_fe_lun,
 294                 sess->se_node_acl->initiatorname);
 295 
 296 out_unlock:
 297         spin_unlock(&dev->dev_reservation_lock);
 298 out:
 299         if (!ret)
 300                 target_complete_cmd(cmd, GOOD);
 301         return ret;
 302 }
 303 
 304 
 305 /*
 306  * Begin SPC-3/SPC-4 Persistent Reservations emulation support
 307  *
 308  * This function is called by those initiator ports who are *NOT*
 309  * the active PR reservation holder when a reservation is present.
 310  */
 311 static int core_scsi3_pr_seq_non_holder(struct se_cmd *cmd, u32 pr_reg_type,
 312                                         bool isid_mismatch)
 313 {
 314         unsigned char *cdb = cmd->t_task_cdb;
 315         struct se_session *se_sess = cmd->se_sess;
 316         struct se_node_acl *nacl = se_sess->se_node_acl;
 317         int other_cdb = 0;
 318         int registered_nexus = 0, ret = 1; /* Conflict by default */
 319         int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
 320         int we = 0; /* Write Exclusive */
 321         int legacy = 0; /* Act like a legacy device and return
 322                          * RESERVATION CONFLICT on some CDBs */
 323 
 324         if (isid_mismatch) {
 325                 registered_nexus = 0;
 326         } else {
 327                 struct se_dev_entry *se_deve;
 328 
 329                 rcu_read_lock();
 330                 se_deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
 331                 if (se_deve)
 332                         registered_nexus = test_bit(DEF_PR_REG_ACTIVE,
 333                                                     &se_deve->deve_flags);
 334                 rcu_read_unlock();
 335         }
 336 
 337         switch (pr_reg_type) {
 338         case PR_TYPE_WRITE_EXCLUSIVE:
 339                 we = 1;
 340         case PR_TYPE_EXCLUSIVE_ACCESS:
 341                 /*
 342                  * Some commands are only allowed for the persistent reservation
 343                  * holder.
 344                  */
 345                 break;
 346         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
 347                 we = 1;
 348                 /* fall through */
 349         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
 350                 /*
 351                  * Some commands are only allowed for registered I_T Nexuses.
 352                  */
 353                 reg_only = 1;
 354                 break;
 355         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
 356                 we = 1;
 357                 /* fall through */
 358         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
 359                 /*
 360                  * Each registered I_T Nexus is a reservation holder.
 361                  */
 362                 all_reg = 1;
 363                 break;
 364         default:
 365                 return -EINVAL;
 366         }
 367         /*
 368          * Referenced from spc4r17 table 45 for *NON* PR holder access
 369          */
 370         switch (cdb[0]) {
 371         case SECURITY_PROTOCOL_IN:
 372                 if (registered_nexus)
 373                         return 0;
 374                 ret = (we) ? 0 : 1;
 375                 break;
 376         case MODE_SENSE:
 377         case MODE_SENSE_10:
 378         case READ_ATTRIBUTE:
 379         case READ_BUFFER:
 380         case RECEIVE_DIAGNOSTIC:
 381                 if (legacy) {
 382                         ret = 1;
 383                         break;
 384                 }
 385                 if (registered_nexus) {
 386                         ret = 0;
 387                         break;
 388                 }
 389                 ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
 390                 break;
 391         case PERSISTENT_RESERVE_OUT:
 392                 /*
 393                  * This follows PERSISTENT_RESERVE_OUT service actions that
 394                  * are allowed in the presence of various reservations.
 395                  * See spc4r17, table 46
 396                  */
 397                 switch (cdb[1] & 0x1f) {
 398                 case PRO_CLEAR:
 399                 case PRO_PREEMPT:
 400                 case PRO_PREEMPT_AND_ABORT:
 401                         ret = (registered_nexus) ? 0 : 1;
 402                         break;
 403                 case PRO_REGISTER:
 404                 case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
 405                         ret = 0;
 406                         break;
 407                 case PRO_REGISTER_AND_MOVE:
 408                 case PRO_RESERVE:
 409                         ret = 1;
 410                         break;
 411                 case PRO_RELEASE:
 412                         ret = (registered_nexus) ? 0 : 1;
 413                         break;
 414                 default:
 415                         pr_err("Unknown PERSISTENT_RESERVE_OUT service"
 416                                 " action: 0x%02x\n", cdb[1] & 0x1f);
 417                         return -EINVAL;
 418                 }
 419                 break;
 420         case RELEASE:
 421         case RELEASE_10:
 422                 /* Handled by CRH=1 in target_scsi2_reservation_release() */
 423                 ret = 0;
 424                 break;
 425         case RESERVE:
 426         case RESERVE_10:
 427                 /* Handled by CRH=1 in target_scsi2_reservation_reserve() */
 428                 ret = 0;
 429                 break;
 430         case TEST_UNIT_READY:
 431                 ret = (legacy) ? 1 : 0; /* Conflict for legacy */
 432                 break;
 433         case MAINTENANCE_IN:
 434                 switch (cdb[1] & 0x1f) {
 435                 case MI_MANAGEMENT_PROTOCOL_IN:
 436                         if (registered_nexus) {
 437                                 ret = 0;
 438                                 break;
 439                         }
 440                         ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
 441                         break;
 442                 case MI_REPORT_SUPPORTED_OPERATION_CODES:
 443                 case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
 444                         if (legacy) {
 445                                 ret = 1;
 446                                 break;
 447                         }
 448                         if (registered_nexus) {
 449                                 ret = 0;
 450                                 break;
 451                         }
 452                         ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
 453                         break;
 454                 case MI_REPORT_ALIASES:
 455                 case MI_REPORT_IDENTIFYING_INFORMATION:
 456                 case MI_REPORT_PRIORITY:
 457                 case MI_REPORT_TARGET_PGS:
 458                 case MI_REPORT_TIMESTAMP:
 459                         ret = 0; /* Allowed */
 460                         break;
 461                 default:
 462                         pr_err("Unknown MI Service Action: 0x%02x\n",
 463                                 (cdb[1] & 0x1f));
 464                         return -EINVAL;
 465                 }
 466                 break;
 467         case ACCESS_CONTROL_IN:
 468         case ACCESS_CONTROL_OUT:
 469         case INQUIRY:
 470         case LOG_SENSE:
 471         case SERVICE_ACTION_IN_12:
 472         case REPORT_LUNS:
 473         case REQUEST_SENSE:
 474         case PERSISTENT_RESERVE_IN:
 475                 ret = 0; /*/ Allowed CDBs */
 476                 break;
 477         default:
 478                 other_cdb = 1;
 479                 break;
 480         }
 481         /*
 482          * Case where the CDB is explicitly allowed in the above switch
 483          * statement.
 484          */
 485         if (!ret && !other_cdb) {
 486                 pr_debug("Allowing explicit CDB: 0x%02x for %s"
 487                         " reservation holder\n", cdb[0],
 488                         core_scsi3_pr_dump_type(pr_reg_type));
 489 
 490                 return ret;
 491         }
 492         /*
 493          * Check if write exclusive initiator ports *NOT* holding the
 494          * WRITE_EXCLUSIVE_* reservation.
 495          */
 496         if (we && !registered_nexus) {
 497                 if (cmd->data_direction == DMA_TO_DEVICE) {
 498                         /*
 499                          * Conflict for write exclusive
 500                          */
 501                         pr_debug("%s Conflict for unregistered nexus"
 502                                 " %s CDB: 0x%02x to %s reservation\n",
 503                                 transport_dump_cmd_direction(cmd),
 504                                 se_sess->se_node_acl->initiatorname, cdb[0],
 505                                 core_scsi3_pr_dump_type(pr_reg_type));
 506                         return 1;
 507                 } else {
 508                         /*
 509                          * Allow non WRITE CDBs for all Write Exclusive
 510                          * PR TYPEs to pass for registered and
 511                          * non-registered_nexuxes NOT holding the reservation.
 512                          *
 513                          * We only make noise for the unregisterd nexuses,
 514                          * as we expect registered non-reservation holding
 515                          * nexuses to issue CDBs.
 516                          */
 517 
 518                         if (!registered_nexus) {
 519                                 pr_debug("Allowing implicit CDB: 0x%02x"
 520                                         " for %s reservation on unregistered"
 521                                         " nexus\n", cdb[0],
 522                                         core_scsi3_pr_dump_type(pr_reg_type));
 523                         }
 524 
 525                         return 0;
 526                 }
 527         } else if ((reg_only) || (all_reg)) {
 528                 if (registered_nexus) {
 529                         /*
 530                          * For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
 531                          * allow commands from registered nexuses.
 532                          */
 533 
 534                         pr_debug("Allowing implicit CDB: 0x%02x for %s"
 535                                 " reservation\n", cdb[0],
 536                                 core_scsi3_pr_dump_type(pr_reg_type));
 537 
 538                         return 0;
 539                 }
 540        } else if (we && registered_nexus) {
 541                /*
 542                 * Reads are allowed for Write Exclusive locks
 543                 * from all registrants.
 544                 */
 545                if (cmd->data_direction == DMA_FROM_DEVICE) {
 546                        pr_debug("Allowing READ CDB: 0x%02x for %s"
 547                                " reservation\n", cdb[0],
 548                                core_scsi3_pr_dump_type(pr_reg_type));
 549 
 550                        return 0;
 551                }
 552         }
 553         pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
 554                 " for %s reservation\n", transport_dump_cmd_direction(cmd),
 555                 (registered_nexus) ? "" : "un",
 556                 se_sess->se_node_acl->initiatorname, cdb[0],
 557                 core_scsi3_pr_dump_type(pr_reg_type));
 558 
 559         return 1; /* Conflict by default */
 560 }
 561 
 562 static sense_reason_t
 563 target_scsi3_pr_reservation_check(struct se_cmd *cmd)
 564 {
 565         struct se_device *dev = cmd->se_dev;
 566         struct se_session *sess = cmd->se_sess;
 567         u32 pr_reg_type;
 568         bool isid_mismatch = false;
 569 
 570         if (!dev->dev_pr_res_holder)
 571                 return 0;
 572 
 573         pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
 574         cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
 575         if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
 576                 goto check_nonholder;
 577 
 578         if (dev->dev_pr_res_holder->isid_present_at_reg) {
 579                 if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
 580                     sess->sess_bin_isid) {
 581                         isid_mismatch = true;
 582                         goto check_nonholder;
 583                 }
 584         }
 585 
 586         return 0;
 587 
 588 check_nonholder:
 589         if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type, isid_mismatch))
 590                 return TCM_RESERVATION_CONFLICT;
 591         return 0;
 592 }
 593 
 594 static u32 core_scsi3_pr_generation(struct se_device *dev)
 595 {
 596         u32 prg;
 597 
 598         /*
 599          * PRGeneration field shall contain the value of a 32-bit wrapping
 600          * counter mainted by the device server.
 601          *
 602          * Note that this is done regardless of Active Persist across
 603          * Target PowerLoss (APTPL)
 604          *
 605          * See spc4r17 section 6.3.12 READ_KEYS service action
 606          */
 607         spin_lock(&dev->dev_reservation_lock);
 608         prg = dev->t10_pr.pr_generation++;
 609         spin_unlock(&dev->dev_reservation_lock);
 610 
 611         return prg;
 612 }
 613 
 614 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
 615         struct se_device *dev,
 616         struct se_node_acl *nacl,
 617         struct se_lun *lun,
 618         struct se_dev_entry *dest_deve,
 619         u64 mapped_lun,
 620         unsigned char *isid,
 621         u64 sa_res_key,
 622         int all_tg_pt,
 623         int aptpl)
 624 {
 625         struct t10_pr_registration *pr_reg;
 626 
 627         pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_ATOMIC);
 628         if (!pr_reg) {
 629                 pr_err("Unable to allocate struct t10_pr_registration\n");
 630                 return NULL;
 631         }
 632 
 633         INIT_LIST_HEAD(&pr_reg->pr_reg_list);
 634         INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
 635         INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
 636         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
 637         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
 638         atomic_set(&pr_reg->pr_res_holders, 0);
 639         pr_reg->pr_reg_nacl = nacl;
 640         /*
 641          * For destination registrations for ALL_TG_PT=1 and SPEC_I_PT=1,
 642          * the se_dev_entry->pr_ref will have been already obtained by
 643          * core_get_se_deve_from_rtpi() or __core_scsi3_alloc_registration().
 644          *
 645          * Otherwise, locate se_dev_entry now and obtain a reference until
 646          * registration completes in __core_scsi3_add_registration().
 647          */
 648         if (dest_deve) {
 649                 pr_reg->pr_reg_deve = dest_deve;
 650         } else {
 651                 rcu_read_lock();
 652                 pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
 653                 if (!pr_reg->pr_reg_deve) {
 654                         rcu_read_unlock();
 655                         pr_err("Unable to locate PR deve %s mapped_lun: %llu\n",
 656                                 nacl->initiatorname, mapped_lun);
 657                         kmem_cache_free(t10_pr_reg_cache, pr_reg);
 658                         return NULL;
 659                 }
 660                 kref_get(&pr_reg->pr_reg_deve->pr_kref);
 661                 rcu_read_unlock();
 662         }
 663         pr_reg->pr_res_mapped_lun = mapped_lun;
 664         pr_reg->pr_aptpl_target_lun = lun->unpacked_lun;
 665         pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
 666         pr_reg->pr_res_key = sa_res_key;
 667         pr_reg->pr_reg_all_tg_pt = all_tg_pt;
 668         pr_reg->pr_reg_aptpl = aptpl;
 669         /*
 670          * If an ISID value for this SCSI Initiator Port exists,
 671          * save it to the registration now.
 672          */
 673         if (isid != NULL) {
 674                 pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
 675                 snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
 676                 pr_reg->isid_present_at_reg = 1;
 677         }
 678 
 679         return pr_reg;
 680 }
 681 
 682 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
 683 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
 684 
 685 /*
 686  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
 687  * modes.
 688  */
 689 static struct t10_pr_registration *__core_scsi3_alloc_registration(
 690         struct se_device *dev,
 691         struct se_node_acl *nacl,
 692         struct se_lun *lun,
 693         struct se_dev_entry *deve,
 694         u64 mapped_lun,
 695         unsigned char *isid,
 696         u64 sa_res_key,
 697         int all_tg_pt,
 698         int aptpl)
 699 {
 700         struct se_dev_entry *deve_tmp;
 701         struct se_node_acl *nacl_tmp;
 702         struct se_lun_acl *lacl_tmp;
 703         struct se_lun *lun_tmp, *next, *dest_lun;
 704         const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
 705         struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
 706         int ret;
 707         /*
 708          * Create a registration for the I_T Nexus upon which the
 709          * PROUT REGISTER was received.
 710          */
 711         pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, lun, deve, mapped_lun,
 712                                                     isid, sa_res_key, all_tg_pt,
 713                                                     aptpl);
 714         if (!pr_reg)
 715                 return NULL;
 716         /*
 717          * Return pointer to pr_reg for ALL_TG_PT=0
 718          */
 719         if (!all_tg_pt)
 720                 return pr_reg;
 721         /*
 722          * Create list of matching SCSI Initiator Port registrations
 723          * for ALL_TG_PT=1
 724          */
 725         spin_lock(&dev->se_port_lock);
 726         list_for_each_entry_safe(lun_tmp, next, &dev->dev_sep_list, lun_dev_link) {
 727                 if (!percpu_ref_tryget_live(&lun_tmp->lun_ref))
 728                         continue;
 729                 spin_unlock(&dev->se_port_lock);
 730 
 731                 spin_lock(&lun_tmp->lun_deve_lock);
 732                 list_for_each_entry(deve_tmp, &lun_tmp->lun_deve_list, lun_link) {
 733                         /*
 734                          * This pointer will be NULL for demo mode MappedLUNs
 735                          * that have not been make explicit via a ConfigFS
 736                          * MappedLUN group for the SCSI Initiator Node ACL.
 737                          */
 738                         if (!deve_tmp->se_lun_acl)
 739                                 continue;
 740 
 741                         lacl_tmp = rcu_dereference_check(deve_tmp->se_lun_acl,
 742                                                 lockdep_is_held(&lun_tmp->lun_deve_lock));
 743                         nacl_tmp = lacl_tmp->se_lun_nacl;
 744                         /*
 745                          * Skip the matching struct se_node_acl that is allocated
 746                          * above..
 747                          */
 748                         if (nacl == nacl_tmp)
 749                                 continue;
 750                         /*
 751                          * Only perform PR registrations for target ports on
 752                          * the same fabric module as the REGISTER w/ ALL_TG_PT=1
 753                          * arrived.
 754                          */
 755                         if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
 756                                 continue;
 757                         /*
 758                          * Look for a matching Initiator Node ACL in ASCII format
 759                          */
 760                         if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
 761                                 continue;
 762 
 763                         kref_get(&deve_tmp->pr_kref);
 764                         spin_unlock(&lun_tmp->lun_deve_lock);
 765                         /*
 766                          * Grab a configfs group dependency that is released
 767                          * for the exception path at label out: below, or upon
 768                          * completion of adding ALL_TG_PT=1 registrations in
 769                          * __core_scsi3_add_registration()
 770                          */
 771                         ret = core_scsi3_lunacl_depend_item(deve_tmp);
 772                         if (ret < 0) {
 773                                 pr_err("core_scsi3_lunacl_depend"
 774                                                 "_item() failed\n");
 775                                 percpu_ref_put(&lun_tmp->lun_ref);
 776                                 kref_put(&deve_tmp->pr_kref, target_pr_kref_release);
 777                                 goto out;
 778                         }
 779                         /*
 780                          * Located a matching SCSI Initiator Port on a different
 781                          * port, allocate the pr_reg_atp and attach it to the
 782                          * pr_reg->pr_reg_atp_list that will be processed once
 783                          * the original *pr_reg is processed in
 784                          * __core_scsi3_add_registration()
 785                          */
 786                         dest_lun = rcu_dereference_check(deve_tmp->se_lun,
 787                                 kref_read(&deve_tmp->pr_kref) != 0);
 788 
 789                         pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
 790                                                 nacl_tmp, dest_lun, deve_tmp,
 791                                                 deve_tmp->mapped_lun, NULL,
 792                                                 sa_res_key, all_tg_pt, aptpl);
 793                         if (!pr_reg_atp) {
 794                                 percpu_ref_put(&lun_tmp->lun_ref);
 795                                 core_scsi3_lunacl_undepend_item(deve_tmp);
 796                                 goto out;
 797                         }
 798 
 799                         list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
 800                                       &pr_reg->pr_reg_atp_list);
 801                         spin_lock(&lun_tmp->lun_deve_lock);
 802                 }
 803                 spin_unlock(&lun_tmp->lun_deve_lock);
 804 
 805                 spin_lock(&dev->se_port_lock);
 806                 percpu_ref_put(&lun_tmp->lun_ref);
 807         }
 808         spin_unlock(&dev->se_port_lock);
 809 
 810         return pr_reg;
 811 out:
 812         list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
 813                         &pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
 814                 list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
 815                 core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
 816                 kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
 817         }
 818         kmem_cache_free(t10_pr_reg_cache, pr_reg);
 819         return NULL;
 820 }
 821 
 822 int core_scsi3_alloc_aptpl_registration(
 823         struct t10_reservation *pr_tmpl,
 824         u64 sa_res_key,
 825         unsigned char *i_port,
 826         unsigned char *isid,
 827         u64 mapped_lun,
 828         unsigned char *t_port,
 829         u16 tpgt,
 830         u64 target_lun,
 831         int res_holder,
 832         int all_tg_pt,
 833         u8 type)
 834 {
 835         struct t10_pr_registration *pr_reg;
 836 
 837         if (!i_port || !t_port || !sa_res_key) {
 838                 pr_err("Illegal parameters for APTPL registration\n");
 839                 return -EINVAL;
 840         }
 841 
 842         pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
 843         if (!pr_reg) {
 844                 pr_err("Unable to allocate struct t10_pr_registration\n");
 845                 return -ENOMEM;
 846         }
 847 
 848         INIT_LIST_HEAD(&pr_reg->pr_reg_list);
 849         INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
 850         INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
 851         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
 852         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
 853         atomic_set(&pr_reg->pr_res_holders, 0);
 854         pr_reg->pr_reg_nacl = NULL;
 855         pr_reg->pr_reg_deve = NULL;
 856         pr_reg->pr_res_mapped_lun = mapped_lun;
 857         pr_reg->pr_aptpl_target_lun = target_lun;
 858         pr_reg->pr_res_key = sa_res_key;
 859         pr_reg->pr_reg_all_tg_pt = all_tg_pt;
 860         pr_reg->pr_reg_aptpl = 1;
 861         pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
 862         pr_reg->pr_res_type = type;
 863         /*
 864          * If an ISID value had been saved in APTPL metadata for this
 865          * SCSI Initiator Port, restore it now.
 866          */
 867         if (isid != NULL) {
 868                 pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
 869                 snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
 870                 pr_reg->isid_present_at_reg = 1;
 871         }
 872         /*
 873          * Copy the i_port and t_port information from caller.
 874          */
 875         snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
 876         snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
 877         pr_reg->pr_reg_tpgt = tpgt;
 878         /*
 879          * Set pr_res_holder from caller, the pr_reg who is the reservation
 880          * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
 881          * the Initiator Node LUN ACL from the fabric module is created for
 882          * this registration.
 883          */
 884         pr_reg->pr_res_holder = res_holder;
 885 
 886         list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
 887         pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
 888                         " metadata\n", (res_holder) ? "+reservation" : "");
 889         return 0;
 890 }
 891 
 892 static void core_scsi3_aptpl_reserve(
 893         struct se_device *dev,
 894         struct se_portal_group *tpg,
 895         struct se_node_acl *node_acl,
 896         struct t10_pr_registration *pr_reg)
 897 {
 898         char i_buf[PR_REG_ISID_ID_LEN];
 899 
 900         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
 901         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
 902 
 903         spin_lock(&dev->dev_reservation_lock);
 904         dev->dev_pr_res_holder = pr_reg;
 905         spin_unlock(&dev->dev_reservation_lock);
 906 
 907         pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
 908                 " new reservation holder TYPE: %s ALL_TG_PT: %d\n",
 909                 tpg->se_tpg_tfo->fabric_name,
 910                 core_scsi3_pr_dump_type(pr_reg->pr_res_type),
 911                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
 912         pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
 913                 tpg->se_tpg_tfo->fabric_name, node_acl->initiatorname,
 914                 i_buf);
 915 }
 916 
 917 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
 918                                 struct t10_pr_registration *, enum register_type, int);
 919 
 920 static int __core_scsi3_check_aptpl_registration(
 921         struct se_device *dev,
 922         struct se_portal_group *tpg,
 923         struct se_lun *lun,
 924         u64 target_lun,
 925         struct se_node_acl *nacl,
 926         u64 mapped_lun)
 927 {
 928         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
 929         struct t10_reservation *pr_tmpl = &dev->t10_pr;
 930         unsigned char i_port[PR_APTPL_MAX_IPORT_LEN];
 931         unsigned char t_port[PR_APTPL_MAX_TPORT_LEN];
 932         u16 tpgt;
 933 
 934         memset(i_port, 0, PR_APTPL_MAX_IPORT_LEN);
 935         memset(t_port, 0, PR_APTPL_MAX_TPORT_LEN);
 936         /*
 937          * Copy Initiator Port information from struct se_node_acl
 938          */
 939         snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
 940         snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
 941                         tpg->se_tpg_tfo->tpg_get_wwn(tpg));
 942         tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
 943         /*
 944          * Look for the matching registrations+reservation from those
 945          * created from APTPL metadata.  Note that multiple registrations
 946          * may exist for fabrics that use ISIDs in their SCSI Initiator Port
 947          * TransportIDs.
 948          */
 949         spin_lock(&pr_tmpl->aptpl_reg_lock);
 950         list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
 951                                 pr_reg_aptpl_list) {
 952 
 953                 if (!strcmp(pr_reg->pr_iport, i_port) &&
 954                      (pr_reg->pr_res_mapped_lun == mapped_lun) &&
 955                     !(strcmp(pr_reg->pr_tport, t_port)) &&
 956                      (pr_reg->pr_reg_tpgt == tpgt) &&
 957                      (pr_reg->pr_aptpl_target_lun == target_lun)) {
 958                         /*
 959                          * Obtain the ->pr_reg_deve pointer + reference, that
 960                          * is released by __core_scsi3_add_registration() below.
 961                          */
 962                         rcu_read_lock();
 963                         pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
 964                         if (!pr_reg->pr_reg_deve) {
 965                                 pr_err("Unable to locate PR APTPL %s mapped_lun:"
 966                                         " %llu\n", nacl->initiatorname, mapped_lun);
 967                                 rcu_read_unlock();
 968                                 continue;
 969                         }
 970                         kref_get(&pr_reg->pr_reg_deve->pr_kref);
 971                         rcu_read_unlock();
 972 
 973                         pr_reg->pr_reg_nacl = nacl;
 974                         pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
 975                         list_del(&pr_reg->pr_reg_aptpl_list);
 976                         spin_unlock(&pr_tmpl->aptpl_reg_lock);
 977                         /*
 978                          * At this point all of the pointers in *pr_reg will
 979                          * be setup, so go ahead and add the registration.
 980                          */
 981                         __core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
 982                         /*
 983                          * If this registration is the reservation holder,
 984                          * make that happen now..
 985                          */
 986                         if (pr_reg->pr_res_holder)
 987                                 core_scsi3_aptpl_reserve(dev, tpg,
 988                                                 nacl, pr_reg);
 989                         /*
 990                          * Reenable pr_aptpl_active to accept new metadata
 991                          * updates once the SCSI device is active again..
 992                          */
 993                         spin_lock(&pr_tmpl->aptpl_reg_lock);
 994                         pr_tmpl->pr_aptpl_active = 1;
 995                 }
 996         }
 997         spin_unlock(&pr_tmpl->aptpl_reg_lock);
 998 
 999         return 0;
1000 }
1001 
1002 int core_scsi3_check_aptpl_registration(
1003         struct se_device *dev,
1004         struct se_portal_group *tpg,
1005         struct se_lun *lun,
1006         struct se_node_acl *nacl,
1007         u64 mapped_lun)
1008 {
1009         if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
1010                 return 0;
1011 
1012         return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
1013                                                      lun->unpacked_lun, nacl,
1014                                                      mapped_lun);
1015 }
1016 
1017 static void __core_scsi3_dump_registration(
1018         const struct target_core_fabric_ops *tfo,
1019         struct se_device *dev,
1020         struct se_node_acl *nacl,
1021         struct t10_pr_registration *pr_reg,
1022         enum register_type register_type)
1023 {
1024         struct se_portal_group *se_tpg = nacl->se_tpg;
1025         char i_buf[PR_REG_ISID_ID_LEN];
1026 
1027         memset(&i_buf[0], 0, PR_REG_ISID_ID_LEN);
1028         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1029 
1030         pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
1031                 " Node: %s%s\n", tfo->fabric_name, (register_type == REGISTER_AND_MOVE) ?
1032                 "_AND_MOVE" : (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ?
1033                 "_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
1034                 i_buf);
1035         pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
1036                  tfo->fabric_name, tfo->tpg_get_wwn(se_tpg),
1037                 tfo->tpg_get_tag(se_tpg));
1038         pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1039                 " Port(s)\n",  tfo->fabric_name,
1040                 (pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1041                 dev->transport->name);
1042         pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1043                 " 0x%08x  APTPL: %d\n", tfo->fabric_name,
1044                 pr_reg->pr_res_key, pr_reg->pr_res_generation,
1045                 pr_reg->pr_reg_aptpl);
1046 }
1047 
1048 static void __core_scsi3_add_registration(
1049         struct se_device *dev,
1050         struct se_node_acl *nacl,
1051         struct t10_pr_registration *pr_reg,
1052         enum register_type register_type,
1053         int register_move)
1054 {
1055         const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1056         struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1057         struct t10_reservation *pr_tmpl = &dev->t10_pr;
1058         struct se_dev_entry *deve;
1059 
1060         /*
1061          * Increment PRgeneration counter for struct se_device upon a successful
1062          * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1063          *
1064          * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1065          * action, the struct se_device->dev_reservation_lock will already be held,
1066          * so we do not call core_scsi3_pr_generation() which grabs the lock
1067          * for the REGISTER.
1068          */
1069         pr_reg->pr_res_generation = (register_move) ?
1070                         dev->t10_pr.pr_generation++ :
1071                         core_scsi3_pr_generation(dev);
1072 
1073         spin_lock(&pr_tmpl->registration_lock);
1074         list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1075 
1076         __core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1077         spin_unlock(&pr_tmpl->registration_lock);
1078         /*
1079          * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1080          */
1081         if (!pr_reg->pr_reg_all_tg_pt || register_move)
1082                 goto out;
1083         /*
1084          * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1085          * allocated in __core_scsi3_alloc_registration()
1086          */
1087         list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1088                         &pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1089                 struct se_node_acl *nacl_tmp = pr_reg_tmp->pr_reg_nacl;
1090 
1091                 list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1092 
1093                 pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1094 
1095                 spin_lock(&pr_tmpl->registration_lock);
1096                 list_add_tail(&pr_reg_tmp->pr_reg_list,
1097                               &pr_tmpl->registration_list);
1098 
1099                 __core_scsi3_dump_registration(tfo, dev, nacl_tmp, pr_reg_tmp,
1100                                                register_type);
1101                 spin_unlock(&pr_tmpl->registration_lock);
1102                 /*
1103                  * Drop configfs group dependency reference and deve->pr_kref
1104                  * obtained from  __core_scsi3_alloc_registration() code.
1105                  */
1106                 rcu_read_lock();
1107                 deve = pr_reg_tmp->pr_reg_deve;
1108                 if (deve) {
1109                         set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1110                         core_scsi3_lunacl_undepend_item(deve);
1111                         pr_reg_tmp->pr_reg_deve = NULL;
1112                 }
1113                 rcu_read_unlock();
1114         }
1115 out:
1116         /*
1117          * Drop deve->pr_kref obtained in __core_scsi3_do_alloc_registration()
1118          */
1119         rcu_read_lock();
1120         deve = pr_reg->pr_reg_deve;
1121         if (deve) {
1122                 set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1123                 kref_put(&deve->pr_kref, target_pr_kref_release);
1124                 pr_reg->pr_reg_deve = NULL;
1125         }
1126         rcu_read_unlock();
1127 }
1128 
1129 static int core_scsi3_alloc_registration(
1130         struct se_device *dev,
1131         struct se_node_acl *nacl,
1132         struct se_lun *lun,
1133         struct se_dev_entry *deve,
1134         u64 mapped_lun,
1135         unsigned char *isid,
1136         u64 sa_res_key,
1137         int all_tg_pt,
1138         int aptpl,
1139         enum register_type register_type,
1140         int register_move)
1141 {
1142         struct t10_pr_registration *pr_reg;
1143 
1144         pr_reg = __core_scsi3_alloc_registration(dev, nacl, lun, deve, mapped_lun,
1145                                                  isid, sa_res_key, all_tg_pt,
1146                                                  aptpl);
1147         if (!pr_reg)
1148                 return -EPERM;
1149 
1150         __core_scsi3_add_registration(dev, nacl, pr_reg,
1151                         register_type, register_move);
1152         return 0;
1153 }
1154 
1155 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1156         struct se_device *dev,
1157         struct se_node_acl *nacl,
1158         unsigned char *isid)
1159 {
1160         struct t10_reservation *pr_tmpl = &dev->t10_pr;
1161         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1162         struct se_portal_group *tpg;
1163 
1164         spin_lock(&pr_tmpl->registration_lock);
1165         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1166                         &pr_tmpl->registration_list, pr_reg_list) {
1167                 /*
1168                  * First look for a matching struct se_node_acl
1169                  */
1170                 if (pr_reg->pr_reg_nacl != nacl)
1171                         continue;
1172 
1173                 tpg = pr_reg->pr_reg_nacl->se_tpg;
1174                 /*
1175                  * If this registration does NOT contain a fabric provided
1176                  * ISID, then we have found a match.
1177                  */
1178                 if (!pr_reg->isid_present_at_reg) {
1179                         /*
1180                          * Determine if this SCSI device server requires that
1181                          * SCSI Intiatior TransportID w/ ISIDs is enforced
1182                          * for fabric modules (iSCSI) requiring them.
1183                          */
1184                         if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1185                                 if (dev->dev_attrib.enforce_pr_isids)
1186                                         continue;
1187                         }
1188                         atomic_inc_mb(&pr_reg->pr_res_holders);
1189                         spin_unlock(&pr_tmpl->registration_lock);
1190                         return pr_reg;
1191                 }
1192                 /*
1193                  * If the *pr_reg contains a fabric defined ISID for multi-value
1194                  * SCSI Initiator Port TransportIDs, then we expect a valid
1195                  * matching ISID to be provided by the local SCSI Initiator Port.
1196                  */
1197                 if (!isid)
1198                         continue;
1199                 if (strcmp(isid, pr_reg->pr_reg_isid))
1200                         continue;
1201 
1202                 atomic_inc_mb(&pr_reg->pr_res_holders);
1203                 spin_unlock(&pr_tmpl->registration_lock);
1204                 return pr_reg;
1205         }
1206         spin_unlock(&pr_tmpl->registration_lock);
1207 
1208         return NULL;
1209 }
1210 
1211 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1212         struct se_device *dev,
1213         struct se_node_acl *nacl,
1214         struct se_session *sess)
1215 {
1216         struct se_portal_group *tpg = nacl->se_tpg;
1217         unsigned char buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
1218 
1219         if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1220                 memset(&buf[0], 0, PR_REG_ISID_LEN);
1221                 tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1222                                         PR_REG_ISID_LEN);
1223                 isid_ptr = &buf[0];
1224         }
1225 
1226         return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1227 }
1228 
1229 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1230 {
1231         atomic_dec_mb(&pr_reg->pr_res_holders);
1232 }
1233 
1234 static int core_scsi3_check_implicit_release(
1235         struct se_device *dev,
1236         struct t10_pr_registration *pr_reg)
1237 {
1238         struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1239         struct t10_pr_registration *pr_res_holder;
1240         int ret = 0;
1241 
1242         spin_lock(&dev->dev_reservation_lock);
1243         pr_res_holder = dev->dev_pr_res_holder;
1244         if (!pr_res_holder) {
1245                 spin_unlock(&dev->dev_reservation_lock);
1246                 return ret;
1247         }
1248         if (pr_res_holder == pr_reg) {
1249                 /*
1250                  * Perform an implicit RELEASE if the registration that
1251                  * is being released is holding the reservation.
1252                  *
1253                  * From spc4r17, section 5.7.11.1:
1254                  *
1255                  * e) If the I_T nexus is the persistent reservation holder
1256                  *    and the persistent reservation is not an all registrants
1257                  *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1258                  *    service action or REGISTER AND  IGNORE EXISTING KEY
1259                  *    service action with the SERVICE ACTION RESERVATION KEY
1260                  *    field set to zero (see 5.7.11.3).
1261                  */
1262                 __core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0, 1);
1263                 ret = 1;
1264                 /*
1265                  * For 'All Registrants' reservation types, all existing
1266                  * registrations are still processed as reservation holders
1267                  * in core_scsi3_pr_seq_non_holder() after the initial
1268                  * reservation holder is implicitly released here.
1269                  */
1270         } else if (pr_reg->pr_reg_all_tg_pt &&
1271                   (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1272                           pr_reg->pr_reg_nacl->initiatorname)) &&
1273                   (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1274                 pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1275                         " UNREGISTER while existing reservation with matching"
1276                         " key 0x%016Lx is present from another SCSI Initiator"
1277                         " Port\n", pr_reg->pr_res_key);
1278                 ret = -EPERM;
1279         }
1280         spin_unlock(&dev->dev_reservation_lock);
1281 
1282         return ret;
1283 }
1284 
1285 static void __core_scsi3_free_registration(
1286         struct se_device *dev,
1287         struct t10_pr_registration *pr_reg,
1288         struct list_head *preempt_and_abort_list,
1289         int dec_holders)
1290         __releases(&pr_tmpl->registration_lock)
1291         __acquires(&pr_tmpl->registration_lock)
1292 {
1293         const struct target_core_fabric_ops *tfo =
1294                         pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1295         struct t10_reservation *pr_tmpl = &dev->t10_pr;
1296         struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1297         struct se_dev_entry *deve;
1298         char i_buf[PR_REG_ISID_ID_LEN];
1299 
1300         lockdep_assert_held(&pr_tmpl->registration_lock);
1301 
1302         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1303         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1304 
1305         if (!list_empty(&pr_reg->pr_reg_list))
1306                 list_del(&pr_reg->pr_reg_list);
1307         /*
1308          * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1309          * so call core_scsi3_put_pr_reg() to decrement our reference.
1310          */
1311         if (dec_holders)
1312                 core_scsi3_put_pr_reg(pr_reg);
1313 
1314         spin_unlock(&pr_tmpl->registration_lock);
1315         /*
1316          * Wait until all reference from any other I_T nexuses for this
1317          * *pr_reg have been released.  Because list_del() is called above,
1318          * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1319          * count back to zero, and we release *pr_reg.
1320          */
1321         while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1322                 pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1323                                 tfo->fabric_name);
1324                 cpu_relax();
1325         }
1326 
1327         rcu_read_lock();
1328         deve = target_nacl_find_deve(nacl, pr_reg->pr_res_mapped_lun);
1329         if (deve)
1330                 clear_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1331         rcu_read_unlock();
1332 
1333         spin_lock(&pr_tmpl->registration_lock);
1334         pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1335                 " Node: %s%s\n", tfo->fabric_name,
1336                 pr_reg->pr_reg_nacl->initiatorname,
1337                 i_buf);
1338         pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1339                 " Port(s)\n", tfo->fabric_name,
1340                 (pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1341                 dev->transport->name);
1342         pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1343                 " 0x%08x\n", tfo->fabric_name, pr_reg->pr_res_key,
1344                 pr_reg->pr_res_generation);
1345 
1346         if (!preempt_and_abort_list) {
1347                 pr_reg->pr_reg_deve = NULL;
1348                 pr_reg->pr_reg_nacl = NULL;
1349                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
1350                 return;
1351         }
1352         /*
1353          * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1354          * are released once the ABORT_TASK_SET has completed..
1355          */
1356         list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1357 }
1358 
1359 void core_scsi3_free_pr_reg_from_nacl(
1360         struct se_device *dev,
1361         struct se_node_acl *nacl)
1362 {
1363         struct t10_reservation *pr_tmpl = &dev->t10_pr;
1364         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1365         bool free_reg = false;
1366         /*
1367          * If the passed se_node_acl matches the reservation holder,
1368          * release the reservation.
1369          */
1370         spin_lock(&dev->dev_reservation_lock);
1371         pr_res_holder = dev->dev_pr_res_holder;
1372         if ((pr_res_holder != NULL) &&
1373             (pr_res_holder->pr_reg_nacl == nacl)) {
1374                 __core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0, 1);
1375                 free_reg = true;
1376         }
1377         spin_unlock(&dev->dev_reservation_lock);
1378         /*
1379          * Release any registration associated with the struct se_node_acl.
1380          */
1381         spin_lock(&pr_tmpl->registration_lock);
1382         if (pr_res_holder && free_reg)
1383                 __core_scsi3_free_registration(dev, pr_res_holder, NULL, 0);
1384 
1385         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1386                         &pr_tmpl->registration_list, pr_reg_list) {
1387 
1388                 if (pr_reg->pr_reg_nacl != nacl)
1389                         continue;
1390 
1391                 __core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1392         }
1393         spin_unlock(&pr_tmpl->registration_lock);
1394 }
1395 
1396 void core_scsi3_free_all_registrations(
1397         struct se_device *dev)
1398 {
1399         struct t10_reservation *pr_tmpl = &dev->t10_pr;
1400         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1401 
1402         spin_lock(&dev->dev_reservation_lock);
1403         pr_res_holder = dev->dev_pr_res_holder;
1404         if (pr_res_holder != NULL) {
1405                 struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1406                 __core_scsi3_complete_pro_release(dev, pr_res_nacl,
1407                                                   pr_res_holder, 0, 0);
1408         }
1409         spin_unlock(&dev->dev_reservation_lock);
1410 
1411         spin_lock(&pr_tmpl->registration_lock);
1412         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1413                         &pr_tmpl->registration_list, pr_reg_list) {
1414 
1415                 __core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1416         }
1417         spin_unlock(&pr_tmpl->registration_lock);
1418 
1419         spin_lock(&pr_tmpl->aptpl_reg_lock);
1420         list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1421                                 pr_reg_aptpl_list) {
1422                 list_del(&pr_reg->pr_reg_aptpl_list);
1423                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
1424         }
1425         spin_unlock(&pr_tmpl->aptpl_reg_lock);
1426 }
1427 
1428 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1429 {
1430         return target_depend_item(&tpg->tpg_group.cg_item);
1431 }
1432 
1433 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1434 {
1435         target_undepend_item(&tpg->tpg_group.cg_item);
1436         atomic_dec_mb(&tpg->tpg_pr_ref_count);
1437 }
1438 
1439 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1440 {
1441         if (nacl->dynamic_node_acl)
1442                 return 0;
1443         return target_depend_item(&nacl->acl_group.cg_item);
1444 }
1445 
1446 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1447 {
1448         if (!nacl->dynamic_node_acl)
1449                 target_undepend_item(&nacl->acl_group.cg_item);
1450         atomic_dec_mb(&nacl->acl_pr_ref_count);
1451 }
1452 
1453 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1454 {
1455         struct se_lun_acl *lun_acl;
1456 
1457         /*
1458          * For nacl->dynamic_node_acl=1
1459          */
1460         lun_acl = rcu_dereference_check(se_deve->se_lun_acl,
1461                                 kref_read(&se_deve->pr_kref) != 0);
1462         if (!lun_acl)
1463                 return 0;
1464 
1465         return target_depend_item(&lun_acl->se_lun_group.cg_item);
1466 }
1467 
1468 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1469 {
1470         struct se_lun_acl *lun_acl;
1471 
1472         /*
1473          * For nacl->dynamic_node_acl=1
1474          */
1475         lun_acl = rcu_dereference_check(se_deve->se_lun_acl,
1476                                 kref_read(&se_deve->pr_kref) != 0);
1477         if (!lun_acl) {
1478                 kref_put(&se_deve->pr_kref, target_pr_kref_release);
1479                 return;
1480         }
1481 
1482         target_undepend_item(&lun_acl->se_lun_group.cg_item);
1483         kref_put(&se_deve->pr_kref, target_pr_kref_release);
1484 }
1485 
1486 static sense_reason_t
1487 core_scsi3_decode_spec_i_port(
1488         struct se_cmd *cmd,
1489         struct se_portal_group *tpg,
1490         unsigned char *l_isid,
1491         u64 sa_res_key,
1492         int all_tg_pt,
1493         int aptpl)
1494 {
1495         struct se_device *dev = cmd->se_dev;
1496         struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1497         struct se_session *se_sess = cmd->se_sess;
1498         struct se_node_acl *dest_node_acl = NULL;
1499         struct se_dev_entry *dest_se_deve = NULL;
1500         struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1501         struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1502         LIST_HEAD(tid_dest_list);
1503         struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1504         unsigned char *buf, *ptr, proto_ident;
1505         const unsigned char *i_str = NULL;
1506         char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
1507         sense_reason_t ret;
1508         u32 tpdl, tid_len = 0;
1509         u32 dest_rtpi = 0;
1510 
1511         /*
1512          * Allocate a struct pr_transport_id_holder and setup the
1513          * local_node_acl pointer and add to struct list_head tid_dest_list
1514          * for add registration processing in the loop of tid_dest_list below.
1515          */
1516         tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1517         if (!tidh_new) {
1518                 pr_err("Unable to allocate tidh_new\n");
1519                 return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1520         }
1521         INIT_LIST_HEAD(&tidh_new->dest_list);
1522         tidh_new->dest_tpg = tpg;
1523         tidh_new->dest_node_acl = se_sess->se_node_acl;
1524 
1525         local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1526                                 se_sess->se_node_acl, cmd->se_lun,
1527                                 NULL, cmd->orig_fe_lun, l_isid,
1528                                 sa_res_key, all_tg_pt, aptpl);
1529         if (!local_pr_reg) {
1530                 kfree(tidh_new);
1531                 return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1532         }
1533         tidh_new->dest_pr_reg = local_pr_reg;
1534         /*
1535          * The local I_T nexus does not hold any configfs dependances,
1536          * so we set tidh_new->dest_se_deve to NULL to prevent the
1537          * configfs_undepend_item() calls in the tid_dest_list loops below.
1538          */
1539         tidh_new->dest_se_deve = NULL;
1540         list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1541 
1542         if (cmd->data_length < 28) {
1543                 pr_warn("SPC-PR: Received PR OUT parameter list"
1544                         " length too small: %u\n", cmd->data_length);
1545                 ret = TCM_INVALID_PARAMETER_LIST;
1546                 goto out;
1547         }
1548 
1549         buf = transport_kmap_data_sg(cmd);
1550         if (!buf) {
1551                 ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1552                 goto out;
1553         }
1554 
1555         /*
1556          * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1557          * first extract TransportID Parameter Data Length, and make sure
1558          * the value matches up to the SCSI expected data transfer length.
1559          */
1560         tpdl = get_unaligned_be32(&buf[24]);
1561 
1562         if ((tpdl + 28) != cmd->data_length) {
1563                 pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1564                         " does not equal CDB data_length: %u\n", tpdl,
1565                         cmd->data_length);
1566                 ret = TCM_INVALID_PARAMETER_LIST;
1567                 goto out_unmap;
1568         }
1569         /*
1570          * Start processing the received transport IDs using the
1571          * receiving I_T Nexus portal's fabric dependent methods to
1572          * obtain the SCSI Initiator Port/Device Identifiers.
1573          */
1574         ptr = &buf[28];
1575 
1576         while (tpdl > 0) {
1577                 struct se_lun *dest_lun, *tmp_lun;
1578 
1579                 proto_ident = (ptr[0] & 0x0f);
1580                 dest_tpg = NULL;
1581 
1582                 spin_lock(&dev->se_port_lock);
1583                 list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
1584                         tmp_tpg = tmp_lun->lun_tpg;
1585 
1586                         /*
1587                          * Look for the matching proto_ident provided by
1588                          * the received TransportID
1589                          */
1590                         if (tmp_tpg->proto_id != proto_ident)
1591                                 continue;
1592                         dest_rtpi = tmp_lun->lun_rtpi;
1593 
1594                         i_str = target_parse_pr_out_transport_id(tmp_tpg,
1595                                         ptr, &tid_len, &iport_ptr);
1596                         if (!i_str)
1597                                 continue;
1598 
1599                         atomic_inc_mb(&tmp_tpg->tpg_pr_ref_count);
1600                         spin_unlock(&dev->se_port_lock);
1601 
1602                         if (core_scsi3_tpg_depend_item(tmp_tpg)) {
1603                                 pr_err(" core_scsi3_tpg_depend_item()"
1604                                         " for tmp_tpg\n");
1605                                 atomic_dec_mb(&tmp_tpg->tpg_pr_ref_count);
1606                                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1607                                 goto out_unmap;
1608                         }
1609                         /*
1610                          * Locate the destination initiator ACL to be registered
1611                          * from the decoded fabric module specific TransportID
1612                          * at *i_str.
1613                          */
1614                         mutex_lock(&tmp_tpg->acl_node_mutex);
1615                         dest_node_acl = __core_tpg_get_initiator_node_acl(
1616                                                 tmp_tpg, i_str);
1617                         if (dest_node_acl)
1618                                 atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
1619                         mutex_unlock(&tmp_tpg->acl_node_mutex);
1620 
1621                         if (!dest_node_acl) {
1622                                 core_scsi3_tpg_undepend_item(tmp_tpg);
1623                                 spin_lock(&dev->se_port_lock);
1624                                 continue;
1625                         }
1626 
1627                         if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
1628                                 pr_err("configfs_depend_item() failed"
1629                                         " for dest_node_acl->acl_group\n");
1630                                 atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
1631                                 core_scsi3_tpg_undepend_item(tmp_tpg);
1632                                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1633                                 goto out_unmap;
1634                         }
1635 
1636                         dest_tpg = tmp_tpg;
1637                         pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1638                                 " %s Port RTPI: %hu\n",
1639                                 dest_tpg->se_tpg_tfo->fabric_name,
1640                                 dest_node_acl->initiatorname, dest_rtpi);
1641 
1642                         spin_lock(&dev->se_port_lock);
1643                         break;
1644                 }
1645                 spin_unlock(&dev->se_port_lock);
1646 
1647                 if (!dest_tpg) {
1648                         pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1649                                         " dest_tpg\n");
1650                         ret = TCM_INVALID_PARAMETER_LIST;
1651                         goto out_unmap;
1652                 }
1653 
1654                 pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1655                         " tid_len: %d for %s + %s\n",
1656                         dest_tpg->se_tpg_tfo->fabric_name, cmd->data_length,
1657                         tpdl, tid_len, i_str, iport_ptr);
1658 
1659                 if (tid_len > tpdl) {
1660                         pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1661                                 " %u for Transport ID: %s\n", tid_len, ptr);
1662                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1663                         core_scsi3_tpg_undepend_item(dest_tpg);
1664                         ret = TCM_INVALID_PARAMETER_LIST;
1665                         goto out_unmap;
1666                 }
1667                 /*
1668                  * Locate the desintation struct se_dev_entry pointer for matching
1669                  * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1670                  * Target Port.
1671                  */
1672                 dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1673                                         dest_rtpi);
1674                 if (!dest_se_deve) {
1675                         pr_err("Unable to locate %s dest_se_deve"
1676                                 " from destination RTPI: %hu\n",
1677                                 dest_tpg->se_tpg_tfo->fabric_name,
1678                                 dest_rtpi);
1679 
1680                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1681                         core_scsi3_tpg_undepend_item(dest_tpg);
1682                         ret = TCM_INVALID_PARAMETER_LIST;
1683                         goto out_unmap;
1684                 }
1685 
1686                 if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
1687                         pr_err("core_scsi3_lunacl_depend_item()"
1688                                         " failed\n");
1689                         kref_put(&dest_se_deve->pr_kref, target_pr_kref_release);
1690                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1691                         core_scsi3_tpg_undepend_item(dest_tpg);
1692                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1693                         goto out_unmap;
1694                 }
1695 
1696                 pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1697                         " dest_se_deve mapped_lun: %llu\n",
1698                         dest_tpg->se_tpg_tfo->fabric_name,
1699                         dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1700 
1701                 /*
1702                  * Skip any TransportIDs that already have a registration for
1703                  * this target port.
1704                  */
1705                 pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1706                                         iport_ptr);
1707                 if (pr_reg_e) {
1708                         core_scsi3_put_pr_reg(pr_reg_e);
1709                         core_scsi3_lunacl_undepend_item(dest_se_deve);
1710                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1711                         core_scsi3_tpg_undepend_item(dest_tpg);
1712                         ptr += tid_len;
1713                         tpdl -= tid_len;
1714                         tid_len = 0;
1715                         continue;
1716                 }
1717                 /*
1718                  * Allocate a struct pr_transport_id_holder and setup
1719                  * the dest_node_acl and dest_se_deve pointers for the
1720                  * loop below.
1721                  */
1722                 tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1723                                 GFP_KERNEL);
1724                 if (!tidh_new) {
1725                         pr_err("Unable to allocate tidh_new\n");
1726                         core_scsi3_lunacl_undepend_item(dest_se_deve);
1727                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1728                         core_scsi3_tpg_undepend_item(dest_tpg);
1729                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1730                         goto out_unmap;
1731                 }
1732                 INIT_LIST_HEAD(&tidh_new->dest_list);
1733                 tidh_new->dest_tpg = dest_tpg;
1734                 tidh_new->dest_node_acl = dest_node_acl;
1735                 tidh_new->dest_se_deve = dest_se_deve;
1736 
1737                 /*
1738                  * Allocate, but do NOT add the registration for the
1739                  * TransportID referenced SCSI Initiator port.  This
1740                  * done because of the following from spc4r17 in section
1741                  * 6.14.3 wrt SPEC_I_PT:
1742                  *
1743                  * "If a registration fails for any initiator port (e.g., if th
1744                  * logical unit does not have enough resources available to
1745                  * hold the registration information), no registrations shall be
1746                  * made, and the command shall be terminated with
1747                  * CHECK CONDITION status."
1748                  *
1749                  * That means we call __core_scsi3_alloc_registration() here,
1750                  * and then call __core_scsi3_add_registration() in the
1751                  * 2nd loop which will never fail.
1752                  */
1753                 dest_lun = rcu_dereference_check(dest_se_deve->se_lun,
1754                                 kref_read(&dest_se_deve->pr_kref) != 0);
1755 
1756                 dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1757                                         dest_node_acl, dest_lun, dest_se_deve,
1758                                         dest_se_deve->mapped_lun, iport_ptr,
1759                                         sa_res_key, all_tg_pt, aptpl);
1760                 if (!dest_pr_reg) {
1761                         core_scsi3_lunacl_undepend_item(dest_se_deve);
1762                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1763                         core_scsi3_tpg_undepend_item(dest_tpg);
1764                         kfree(tidh_new);
1765                         ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1766                         goto out_unmap;
1767                 }
1768                 tidh_new->dest_pr_reg = dest_pr_reg;
1769                 list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1770 
1771                 ptr += tid_len;
1772                 tpdl -= tid_len;
1773                 tid_len = 0;
1774 
1775         }
1776 
1777         transport_kunmap_data_sg(cmd);
1778 
1779         /*
1780          * Go ahead and create a registrations from tid_dest_list for the
1781          * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1782          * and dest_se_deve.
1783          *
1784          * The SA Reservation Key from the PROUT is set for the
1785          * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1786          * means that the TransportID Initiator port will be
1787          * registered on all of the target ports in the SCSI target device
1788          * ALL_TG_PT=0 means the registration will only be for the
1789          * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1790          * was received.
1791          */
1792         list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1793                 dest_tpg = tidh->dest_tpg;
1794                 dest_node_acl = tidh->dest_node_acl;
1795                 dest_se_deve = tidh->dest_se_deve;
1796                 dest_pr_reg = tidh->dest_pr_reg;
1797 
1798                 list_del(&tidh->dest_list);
1799                 kfree(tidh);
1800 
1801                 memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1802                 core_pr_dump_initiator_port(dest_pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1803 
1804                 __core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1805                                         dest_pr_reg, 0, 0);
1806 
1807                 pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1808                         " registered Transport ID for Node: %s%s Mapped LUN:"
1809                         " %llu\n", dest_tpg->se_tpg_tfo->fabric_name,
1810                         dest_node_acl->initiatorname, i_buf, (dest_se_deve) ?
1811                         dest_se_deve->mapped_lun : 0);
1812 
1813                 if (!dest_se_deve) {
1814                         kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
1815                                  target_pr_kref_release);
1816                         continue;
1817                 }
1818                 core_scsi3_lunacl_undepend_item(dest_se_deve);
1819                 core_scsi3_nodeacl_undepend_item(dest_node_acl);
1820                 core_scsi3_tpg_undepend_item(dest_tpg);
1821         }
1822 
1823         return 0;
1824 out_unmap:
1825         transport_kunmap_data_sg(cmd);
1826 out:
1827         /*
1828          * For the failure case, release everything from tid_dest_list
1829          * including *dest_pr_reg and the configfs dependances..
1830          */
1831         list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1832                 dest_tpg = tidh->dest_tpg;
1833                 dest_node_acl = tidh->dest_node_acl;
1834                 dest_se_deve = tidh->dest_se_deve;
1835                 dest_pr_reg = tidh->dest_pr_reg;
1836 
1837                 list_del(&tidh->dest_list);
1838                 kfree(tidh);
1839                 /*
1840                  * Release any extra ALL_TG_PT=1 registrations for
1841                  * the SPEC_I_PT=1 case.
1842                  */
1843                 list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1844                                 &dest_pr_reg->pr_reg_atp_list,
1845                                 pr_reg_atp_mem_list) {
1846                         list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1847                         core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1848                         kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1849                 }
1850 
1851                 kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1852 
1853                 if (!dest_se_deve) {
1854                         kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
1855                                  target_pr_kref_release);
1856                         continue;
1857                 }
1858                 core_scsi3_lunacl_undepend_item(dest_se_deve);
1859                 core_scsi3_nodeacl_undepend_item(dest_node_acl);
1860                 core_scsi3_tpg_undepend_item(dest_tpg);
1861         }
1862         return ret;
1863 }
1864 
1865 static int core_scsi3_update_aptpl_buf(
1866         struct se_device *dev,
1867         unsigned char *buf,
1868         u32 pr_aptpl_buf_len)
1869 {
1870         struct se_portal_group *tpg;
1871         struct t10_pr_registration *pr_reg;
1872         unsigned char tmp[512], isid_buf[32];
1873         ssize_t len = 0;
1874         int reg_count = 0;
1875         int ret = 0;
1876 
1877         spin_lock(&dev->dev_reservation_lock);
1878         spin_lock(&dev->t10_pr.registration_lock);
1879         /*
1880          * Walk the registration list..
1881          */
1882         list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
1883                         pr_reg_list) {
1884 
1885                 tmp[0] = '\0';
1886                 isid_buf[0] = '\0';
1887                 tpg = pr_reg->pr_reg_nacl->se_tpg;
1888                 /*
1889                  * Write out any ISID value to APTPL metadata that was included
1890                  * in the original registration.
1891                  */
1892                 if (pr_reg->isid_present_at_reg)
1893                         snprintf(isid_buf, 32, "initiator_sid=%s\n",
1894                                         pr_reg->pr_reg_isid);
1895                 /*
1896                  * Include special metadata if the pr_reg matches the
1897                  * reservation holder.
1898                  */
1899                 if (dev->dev_pr_res_holder == pr_reg) {
1900                         snprintf(tmp, 512, "PR_REG_START: %d"
1901                                 "\ninitiator_fabric=%s\n"
1902                                 "initiator_node=%s\n%s"
1903                                 "sa_res_key=%llu\n"
1904                                 "res_holder=1\nres_type=%02x\n"
1905                                 "res_scope=%02x\nres_all_tg_pt=%d\n"
1906                                 "mapped_lun=%llu\n", reg_count,
1907                                 tpg->se_tpg_tfo->fabric_name,
1908                                 pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1909                                 pr_reg->pr_res_key, pr_reg->pr_res_type,
1910                                 pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1911                                 pr_reg->pr_res_mapped_lun);
1912                 } else {
1913                         snprintf(tmp, 512, "PR_REG_START: %d\n"
1914                                 "initiator_fabric=%s\ninitiator_node=%s\n%s"
1915                                 "sa_res_key=%llu\nres_holder=0\n"
1916                                 "res_all_tg_pt=%d\nmapped_lun=%llu\n",
1917                                 reg_count, tpg->se_tpg_tfo->fabric_name,
1918                                 pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1919                                 pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1920                                 pr_reg->pr_res_mapped_lun);
1921                 }
1922 
1923                 if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1924                         pr_err("Unable to update renaming APTPL metadata,"
1925                                " reallocating larger buffer\n");
1926                         ret = -EMSGSIZE;
1927                         goto out;
1928                 }
1929                 len += sprintf(buf+len, "%s", tmp);
1930 
1931                 /*
1932                  * Include information about the associated SCSI target port.
1933                  */
1934                 snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1935                         "tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%llu\nPR_REG_END:"
1936                         " %d\n", tpg->se_tpg_tfo->fabric_name,
1937                         tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1938                         tpg->se_tpg_tfo->tpg_get_tag(tpg),
1939                         pr_reg->tg_pt_sep_rtpi, pr_reg->pr_aptpl_target_lun,
1940                         reg_count);
1941 
1942                 if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1943                         pr_err("Unable to update renaming APTPL metadata,"
1944                                " reallocating larger buffer\n");
1945                         ret = -EMSGSIZE;
1946                         goto out;
1947                 }
1948                 len += sprintf(buf+len, "%s", tmp);
1949                 reg_count++;
1950         }
1951 
1952         if (!reg_count)
1953                 len += sprintf(buf+len, "No Registrations or Reservations");
1954 
1955 out:
1956         spin_unlock(&dev->t10_pr.registration_lock);
1957         spin_unlock(&dev->dev_reservation_lock);
1958 
1959         return ret;
1960 }
1961 
1962 static int __core_scsi3_write_aptpl_to_file(
1963         struct se_device *dev,
1964         unsigned char *buf)
1965 {
1966         struct t10_wwn *wwn = &dev->t10_wwn;
1967         struct file *file;
1968         int flags = O_RDWR | O_CREAT | O_TRUNC;
1969         char *path;
1970         u32 pr_aptpl_buf_len;
1971         int ret;
1972         loff_t pos = 0;
1973 
1974         path = kasprintf(GFP_KERNEL, "%s/pr/aptpl_%s", db_root,
1975                         &wwn->unit_serial[0]);
1976         if (!path)
1977                 return -ENOMEM;
1978 
1979         file = filp_open(path, flags, 0600);
1980         if (IS_ERR(file)) {
1981                 pr_err("filp_open(%s) for APTPL metadata"
1982                         " failed\n", path);
1983                 kfree(path);
1984                 return PTR_ERR(file);
1985         }
1986 
1987         pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
1988 
1989         ret = kernel_write(file, buf, pr_aptpl_buf_len, &pos);
1990 
1991         if (ret < 0)
1992                 pr_debug("Error writing APTPL metadata file: %s\n", path);
1993         fput(file);
1994         kfree(path);
1995 
1996         return (ret < 0) ? -EIO : 0;
1997 }
1998 
1999 /*
2000  * Clear the APTPL metadata if APTPL has been disabled, otherwise
2001  * write out the updated metadata to struct file for this SCSI device.
2002  */
2003 static sense_reason_t core_scsi3_update_and_write_aptpl(struct se_device *dev, bool aptpl)
2004 {
2005         unsigned char *buf;
2006         int rc, len = PR_APTPL_BUF_LEN;
2007 
2008         if (!aptpl) {
2009                 char *null_buf = "No Registrations or Reservations\n";
2010 
2011                 rc = __core_scsi3_write_aptpl_to_file(dev, null_buf);
2012                 dev->t10_pr.pr_aptpl_active = 0;
2013                 pr_debug("SPC-3 PR: Set APTPL Bit Deactivated\n");
2014 
2015                 if (rc)
2016                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2017 
2018                 return 0;
2019         }
2020 retry:
2021         buf = vzalloc(len);
2022         if (!buf)
2023                 return TCM_OUT_OF_RESOURCES;
2024 
2025         rc = core_scsi3_update_aptpl_buf(dev, buf, len);
2026         if (rc < 0) {
2027                 vfree(buf);
2028                 len *= 2;
2029                 goto retry;
2030         }
2031 
2032         rc = __core_scsi3_write_aptpl_to_file(dev, buf);
2033         if (rc != 0) {
2034                 pr_err("SPC-3 PR: Could not update APTPL\n");
2035                 vfree(buf);
2036                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2037         }
2038         dev->t10_pr.pr_aptpl_active = 1;
2039         vfree(buf);
2040         pr_debug("SPC-3 PR: Set APTPL Bit Activated\n");
2041         return 0;
2042 }
2043 
2044 static sense_reason_t
2045 core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
2046                 bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type)
2047 {
2048         struct se_session *se_sess = cmd->se_sess;
2049         struct se_device *dev = cmd->se_dev;
2050         struct se_lun *se_lun = cmd->se_lun;
2051         struct se_portal_group *se_tpg;
2052         struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp;
2053         struct t10_reservation *pr_tmpl = &dev->t10_pr;
2054         unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2055         sense_reason_t ret = TCM_NO_SENSE;
2056         int pr_holder = 0, type;
2057 
2058         if (!se_sess || !se_lun) {
2059                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2060                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2061         }
2062         se_tpg = se_sess->se_tpg;
2063 
2064         if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2065                 memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2066                 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2067                                 PR_REG_ISID_LEN);
2068                 isid_ptr = &isid_buf[0];
2069         }
2070         /*
2071          * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2072          */
2073         pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2074         if (!pr_reg) {
2075                 if (res_key) {
2076                         pr_warn("SPC-3 PR: Reservation Key non-zero"
2077                                 " for SA REGISTER, returning CONFLICT\n");
2078                         return TCM_RESERVATION_CONFLICT;
2079                 }
2080                 /*
2081                  * Do nothing but return GOOD status.
2082                  */
2083                 if (!sa_res_key)
2084                         return 0;
2085 
2086                 if (!spec_i_pt) {
2087                         /*
2088                          * Perform the Service Action REGISTER on the Initiator
2089                          * Port Endpoint that the PRO was received from on the
2090                          * Logical Unit of the SCSI device server.
2091                          */
2092                         if (core_scsi3_alloc_registration(cmd->se_dev,
2093                                         se_sess->se_node_acl, cmd->se_lun,
2094                                         NULL, cmd->orig_fe_lun, isid_ptr,
2095                                         sa_res_key, all_tg_pt, aptpl,
2096                                         register_type, 0)) {
2097                                 pr_err("Unable to allocate"
2098                                         " struct t10_pr_registration\n");
2099                                 return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
2100                         }
2101                 } else {
2102                         /*
2103                          * Register both the Initiator port that received
2104                          * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2105                          * TransportID from Parameter list and loop through
2106                          * fabric dependent parameter list while calling
2107                          * logic from of core_scsi3_alloc_registration() for
2108                          * each TransportID provided SCSI Initiator Port/Device
2109                          */
2110                         ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2111                                         isid_ptr, sa_res_key, all_tg_pt, aptpl);
2112                         if (ret != 0)
2113                                 return ret;
2114                 }
2115                 return core_scsi3_update_and_write_aptpl(dev, aptpl);
2116         }
2117 
2118         /* ok, existing registration */
2119 
2120         if ((register_type == REGISTER) && (res_key != pr_reg->pr_res_key)) {
2121                 pr_err("SPC-3 PR REGISTER: Received"
2122                        " res_key: 0x%016Lx does not match"
2123                        " existing SA REGISTER res_key:"
2124                        " 0x%016Lx\n", res_key,
2125                        pr_reg->pr_res_key);
2126                 ret = TCM_RESERVATION_CONFLICT;
2127                 goto out;
2128         }
2129 
2130         if (spec_i_pt) {
2131                 pr_err("SPC-3 PR REGISTER: SPEC_I_PT"
2132                         " set on a registered nexus\n");
2133                 ret = TCM_INVALID_PARAMETER_LIST;
2134                 goto out;
2135         }
2136 
2137         /*
2138          * An existing ALL_TG_PT=1 registration being released
2139          * must also set ALL_TG_PT=1 in the incoming PROUT.
2140          */
2141         if (pr_reg->pr_reg_all_tg_pt && !all_tg_pt) {
2142                 pr_err("SPC-3 PR REGISTER: ALL_TG_PT=1"
2143                         " registration exists, but ALL_TG_PT=1 bit not"
2144                         " present in received PROUT\n");
2145                 ret = TCM_INVALID_CDB_FIELD;
2146                 goto out;
2147         }
2148 
2149         /*
2150          * sa_res_key=1 Change Reservation Key for registered I_T Nexus.
2151          */
2152         if (sa_res_key) {
2153                 /*
2154                  * Increment PRgeneration counter for struct se_device"
2155                  * upon a successful REGISTER, see spc4r17 section 6.3.2
2156                  * READ_KEYS service action.
2157                  */
2158                 pr_reg->pr_res_generation = core_scsi3_pr_generation(cmd->se_dev);
2159                 pr_reg->pr_res_key = sa_res_key;
2160                 pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2161                          " Key for %s to: 0x%016Lx PRgeneration:"
2162                          " 0x%08x\n", cmd->se_tfo->fabric_name,
2163                          (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ? "_AND_IGNORE_EXISTING_KEY" : "",
2164                          pr_reg->pr_reg_nacl->initiatorname,
2165                          pr_reg->pr_res_key, pr_reg->pr_res_generation);
2166 
2167         } else {
2168                 /*
2169                  * sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
2170                  */
2171                 type = pr_reg->pr_res_type;
2172                 pr_holder = core_scsi3_check_implicit_release(cmd->se_dev,
2173                                                               pr_reg);
2174                 if (pr_holder < 0) {
2175                         ret = TCM_RESERVATION_CONFLICT;
2176                         goto out;
2177                 }
2178 
2179                 spin_lock(&pr_tmpl->registration_lock);
2180                 /*
2181                  * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2182                  * and matching pr_res_key.
2183                  */
2184                 if (pr_reg->pr_reg_all_tg_pt) {
2185                         list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2186                                         &pr_tmpl->registration_list,
2187                                         pr_reg_list) {
2188 
2189                                 if (!pr_reg_p->pr_reg_all_tg_pt)
2190                                         continue;
2191                                 if (pr_reg_p->pr_res_key != res_key)
2192                                         continue;
2193                                 if (pr_reg == pr_reg_p)
2194                                         continue;
2195                                 if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2196                                            pr_reg_p->pr_reg_nacl->initiatorname))
2197                                         continue;
2198 
2199                                 __core_scsi3_free_registration(dev,
2200                                                 pr_reg_p, NULL, 0);
2201                         }
2202                 }
2203 
2204                 /*
2205                  * Release the calling I_T Nexus registration now..
2206                  */
2207                 __core_scsi3_free_registration(cmd->se_dev, pr_reg, NULL, 1);
2208                 pr_reg = NULL;
2209 
2210                 /*
2211                  * From spc4r17, section 5.7.11.3 Unregistering
2212                  *
2213                  * If the persistent reservation is a registrants only
2214                  * type, the device server shall establish a unit
2215                  * attention condition for the initiator port associated
2216                  * with every registered I_T nexus except for the I_T
2217                  * nexus on which the PERSISTENT RESERVE OUT command was
2218                  * received, with the additional sense code set to
2219                  * RESERVATIONS RELEASED.
2220                  */
2221                 if (pr_holder &&
2222                     (type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY ||
2223                      type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY)) {
2224                         list_for_each_entry(pr_reg_p,
2225                                         &pr_tmpl->registration_list,
2226                                         pr_reg_list) {
2227 
2228                                 target_ua_allocate_lun(
2229                                         pr_reg_p->pr_reg_nacl,
2230                                         pr_reg_p->pr_res_mapped_lun,
2231                                         0x2A,
2232                                         ASCQ_2AH_RESERVATIONS_RELEASED);
2233                         }
2234                 }
2235 
2236                 spin_unlock(&pr_tmpl->registration_lock);
2237         }
2238 
2239         ret = core_scsi3_update_and_write_aptpl(dev, aptpl);
2240 
2241 out:
2242         if (pr_reg)
2243                 core_scsi3_put_pr_reg(pr_reg);
2244         return ret;
2245 }
2246 
2247 unsigned char *core_scsi3_pr_dump_type(int type)
2248 {
2249         switch (type) {
2250         case PR_TYPE_WRITE_EXCLUSIVE:
2251                 return "Write Exclusive Access";
2252         case PR_TYPE_EXCLUSIVE_ACCESS:
2253                 return "Exclusive Access";
2254         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2255                 return "Write Exclusive Access, Registrants Only";
2256         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2257                 return "Exclusive Access, Registrants Only";
2258         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2259                 return "Write Exclusive Access, All Registrants";
2260         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2261                 return "Exclusive Access, All Registrants";
2262         default:
2263                 break;
2264         }
2265 
2266         return "Unknown SPC-3 PR Type";
2267 }
2268 
2269 static sense_reason_t
2270 core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
2271 {
2272         struct se_device *dev = cmd->se_dev;
2273         struct se_session *se_sess = cmd->se_sess;
2274         struct se_lun *se_lun = cmd->se_lun;
2275         struct t10_pr_registration *pr_reg, *pr_res_holder;
2276         struct t10_reservation *pr_tmpl = &dev->t10_pr;
2277         char i_buf[PR_REG_ISID_ID_LEN];
2278         sense_reason_t ret;
2279 
2280         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2281 
2282         if (!se_sess || !se_lun) {
2283                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2284                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2285         }
2286         /*
2287          * Locate the existing *pr_reg via struct se_node_acl pointers
2288          */
2289         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2290                                 se_sess);
2291         if (!pr_reg) {
2292                 pr_err("SPC-3 PR: Unable to locate"
2293                         " PR_REGISTERED *pr_reg for RESERVE\n");
2294                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2295         }
2296         /*
2297          * From spc4r17 Section 5.7.9: Reserving:
2298          *
2299          * An application client creates a persistent reservation by issuing
2300          * a PERSISTENT RESERVE OUT command with RESERVE service action through
2301          * a registered I_T nexus with the following parameters:
2302          *    a) RESERVATION KEY set to the value of the reservation key that is
2303          *       registered with the logical unit for the I_T nexus; and
2304          */
2305         if (res_key != pr_reg->pr_res_key) {
2306                 pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2307                         " does not match existing SA REGISTER res_key:"
2308                         " 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2309                 ret = TCM_RESERVATION_CONFLICT;
2310                 goto out_put_pr_reg;
2311         }
2312         /*
2313          * From spc4r17 Section 5.7.9: Reserving:
2314          *
2315          * From above:
2316          *  b) TYPE field and SCOPE field set to the persistent reservation
2317          *     being created.
2318          *
2319          * Only one persistent reservation is allowed at a time per logical unit
2320          * and that persistent reservation has a scope of LU_SCOPE.
2321          */
2322         if (scope != PR_SCOPE_LU_SCOPE) {
2323                 pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2324                 ret = TCM_INVALID_PARAMETER_LIST;
2325                 goto out_put_pr_reg;
2326         }
2327         /*
2328          * See if we have an existing PR reservation holder pointer at
2329          * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2330          * *pr_res_holder.
2331          */
2332         spin_lock(&dev->dev_reservation_lock);
2333         pr_res_holder = dev->dev_pr_res_holder;
2334         if (pr_res_holder) {
2335                 /*
2336                  * From spc4r17 Section 5.7.9: Reserving:
2337                  *
2338                  * If the device server receives a PERSISTENT RESERVE OUT
2339                  * command from an I_T nexus other than a persistent reservation
2340                  * holder (see 5.7.10) that attempts to create a persistent
2341                  * reservation when a persistent reservation already exists for
2342                  * the logical unit, then the command shall be completed with
2343                  * RESERVATION CONFLICT status.
2344                  */
2345                 if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2346                         struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2347                         pr_err("SPC-3 PR: Attempted RESERVE from"
2348                                 " [%s]: %s while reservation already held by"
2349                                 " [%s]: %s, returning RESERVATION_CONFLICT\n",
2350                                 cmd->se_tfo->fabric_name,
2351                                 se_sess->se_node_acl->initiatorname,
2352                                 pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2353                                 pr_res_holder->pr_reg_nacl->initiatorname);
2354 
2355                         spin_unlock(&dev->dev_reservation_lock);
2356                         ret = TCM_RESERVATION_CONFLICT;
2357                         goto out_put_pr_reg;
2358                 }
2359                 /*
2360                  * From spc4r17 Section 5.7.9: Reserving:
2361                  *
2362                  * If a persistent reservation holder attempts to modify the
2363                  * type or scope of an existing persistent reservation, the
2364                  * command shall be completed with RESERVATION CONFLICT status.
2365                  */
2366                 if ((pr_res_holder->pr_res_type != type) ||
2367                     (pr_res_holder->pr_res_scope != scope)) {
2368                         struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2369                         pr_err("SPC-3 PR: Attempted RESERVE from"
2370                                 " [%s]: %s trying to change TYPE and/or SCOPE,"
2371                                 " while reservation already held by [%s]: %s,"
2372                                 " returning RESERVATION_CONFLICT\n",
2373                                 cmd->se_tfo->fabric_name,
2374                                 se_sess->se_node_acl->initiatorname,
2375                                 pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2376                                 pr_res_holder->pr_reg_nacl->initiatorname);
2377 
2378                         spin_unlock(&dev->dev_reservation_lock);
2379                         ret = TCM_RESERVATION_CONFLICT;
2380                         goto out_put_pr_reg;
2381                 }
2382                 /*
2383                  * From spc4r17 Section 5.7.9: Reserving:
2384                  *
2385                  * If the device server receives a PERSISTENT RESERVE OUT
2386                  * command with RESERVE service action where the TYPE field and
2387                  * the SCOPE field contain the same values as the existing type
2388                  * and scope from a persistent reservation holder, it shall not
2389                  * make any change to the existing persistent reservation and
2390                  * shall completethe command with GOOD status.
2391                  */
2392                 spin_unlock(&dev->dev_reservation_lock);
2393                 ret = 0;
2394                 goto out_put_pr_reg;
2395         }
2396         /*
2397          * Otherwise, our *pr_reg becomes the PR reservation holder for said
2398          * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2399          */
2400         pr_reg->pr_res_scope = scope;
2401         pr_reg->pr_res_type = type;
2402         pr_reg->pr_res_holder = 1;
2403         dev->dev_pr_res_holder = pr_reg;
2404         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2405 
2406         pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2407                 " reservation holder TYPE: %s ALL_TG_PT: %d\n",
2408                 cmd->se_tfo->fabric_name, core_scsi3_pr_dump_type(type),
2409                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2410         pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2411                         cmd->se_tfo->fabric_name,
2412                         se_sess->se_node_acl->initiatorname,
2413                         i_buf);
2414         spin_unlock(&dev->dev_reservation_lock);
2415 
2416         if (pr_tmpl->pr_aptpl_active)
2417                 core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2418 
2419         ret = 0;
2420 out_put_pr_reg:
2421         core_scsi3_put_pr_reg(pr_reg);
2422         return ret;
2423 }
2424 
2425 static sense_reason_t
2426 core_scsi3_emulate_pro_reserve(struct se_cmd *cmd, int type, int scope,
2427                 u64 res_key)
2428 {
2429         switch (type) {
2430         case PR_TYPE_WRITE_EXCLUSIVE:
2431         case PR_TYPE_EXCLUSIVE_ACCESS:
2432         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2433         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2434         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2435         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2436                 return core_scsi3_pro_reserve(cmd, type, scope, res_key);
2437         default:
2438                 pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2439                         " 0x%02x\n", type);
2440                 return TCM_INVALID_CDB_FIELD;
2441         }
2442 }
2443 
2444 static void __core_scsi3_complete_pro_release(
2445         struct se_device *dev,
2446         struct se_node_acl *se_nacl,
2447         struct t10_pr_registration *pr_reg,
2448         int explicit,
2449         int unreg)
2450 {
2451         const struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2452         char i_buf[PR_REG_ISID_ID_LEN];
2453         int pr_res_type = 0, pr_res_scope = 0;
2454 
2455         lockdep_assert_held(&dev->dev_reservation_lock);
2456 
2457         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2458         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2459         /*
2460          * Go ahead and release the current PR reservation holder.
2461          * If an All Registrants reservation is currently active and
2462          * a unregister operation is requested, replace the current
2463          * dev_pr_res_holder with another active registration.
2464          */
2465         if (dev->dev_pr_res_holder) {
2466                 pr_res_type = dev->dev_pr_res_holder->pr_res_type;
2467                 pr_res_scope = dev->dev_pr_res_holder->pr_res_scope;
2468                 dev->dev_pr_res_holder->pr_res_type = 0;
2469                 dev->dev_pr_res_holder->pr_res_scope = 0;
2470                 dev->dev_pr_res_holder->pr_res_holder = 0;
2471                 dev->dev_pr_res_holder = NULL;
2472         }
2473         if (!unreg)
2474                 goto out;
2475 
2476         spin_lock(&dev->t10_pr.registration_lock);
2477         list_del_init(&pr_reg->pr_reg_list);
2478         /*
2479          * If the I_T nexus is a reservation holder, the persistent reservation
2480          * is of an all registrants type, and the I_T nexus is the last remaining
2481          * registered I_T nexus, then the device server shall also release the
2482          * persistent reservation.
2483          */
2484         if (!list_empty(&dev->t10_pr.registration_list) &&
2485             ((pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2486              (pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))) {
2487                 dev->dev_pr_res_holder =
2488                         list_entry(dev->t10_pr.registration_list.next,
2489                                    struct t10_pr_registration, pr_reg_list);
2490                 dev->dev_pr_res_holder->pr_res_type = pr_res_type;
2491                 dev->dev_pr_res_holder->pr_res_scope = pr_res_scope;
2492                 dev->dev_pr_res_holder->pr_res_holder = 1;
2493         }
2494         spin_unlock(&dev->t10_pr.registration_lock);
2495 out:
2496         if (!dev->dev_pr_res_holder) {
2497                 pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2498                         " reservation holder TYPE: %s ALL_TG_PT: %d\n",
2499                         tfo->fabric_name, (explicit) ? "explicit" :
2500                         "implicit", core_scsi3_pr_dump_type(pr_res_type),
2501                         (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2502         }
2503         pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2504                 tfo->fabric_name, se_nacl->initiatorname,
2505                 i_buf);
2506         /*
2507          * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2508          */
2509         pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2510 }
2511 
2512 static sense_reason_t
2513 core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
2514                 u64 res_key)
2515 {
2516         struct se_device *dev = cmd->se_dev;
2517         struct se_session *se_sess = cmd->se_sess;
2518         struct se_lun *se_lun = cmd->se_lun;
2519         struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2520         struct t10_reservation *pr_tmpl = &dev->t10_pr;
2521         sense_reason_t ret = 0;
2522 
2523         if (!se_sess || !se_lun) {
2524                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2525                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2526         }
2527         /*
2528          * Locate the existing *pr_reg via struct se_node_acl pointers
2529          */
2530         pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2531         if (!pr_reg) {
2532                 pr_err("SPC-3 PR: Unable to locate"
2533                         " PR_REGISTERED *pr_reg for RELEASE\n");
2534                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2535         }
2536         /*
2537          * From spc4r17 Section 5.7.11.2 Releasing:
2538          *
2539          * If there is no persistent reservation or in response to a persistent
2540          * reservation release request from a registered I_T nexus that is not a
2541          * persistent reservation holder (see 5.7.10), the device server shall
2542          * do the following:
2543          *
2544          *     a) Not release the persistent reservation, if any;
2545          *     b) Not remove any registrations; and
2546          *     c) Complete the command with GOOD status.
2547          */
2548         spin_lock(&dev->dev_reservation_lock);
2549         pr_res_holder = dev->dev_pr_res_holder;
2550         if (!pr_res_holder) {
2551                 /*
2552                  * No persistent reservation, return GOOD status.
2553                  */
2554                 spin_unlock(&dev->dev_reservation_lock);
2555                 goto out_put_pr_reg;
2556         }
2557 
2558         if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2559                 /*
2560                  * Release request from a registered I_T nexus that is not a
2561                  * persistent reservation holder. return GOOD status.
2562                  */
2563                 spin_unlock(&dev->dev_reservation_lock);
2564                 goto out_put_pr_reg;
2565         }
2566 
2567         /*
2568          * From spc4r17 Section 5.7.11.2 Releasing:
2569          *
2570          * Only the persistent reservation holder (see 5.7.10) is allowed to
2571          * release a persistent reservation.
2572          *
2573          * An application client releases the persistent reservation by issuing
2574          * a PERSISTENT RESERVE OUT command with RELEASE service action through
2575          * an I_T nexus that is a persistent reservation holder with the
2576          * following parameters:
2577          *
2578          *     a) RESERVATION KEY field set to the value of the reservation key
2579          *        that is registered with the logical unit for the I_T nexus;
2580          */
2581         if (res_key != pr_reg->pr_res_key) {
2582                 pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2583                         " does not match existing SA REGISTER res_key:"
2584                         " 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2585                 spin_unlock(&dev->dev_reservation_lock);
2586                 ret = TCM_RESERVATION_CONFLICT;
2587                 goto out_put_pr_reg;
2588         }
2589         /*
2590          * From spc4r17 Section 5.7.11.2 Releasing and above:
2591          *
2592          * b) TYPE field and SCOPE field set to match the persistent
2593          *    reservation being released.
2594          */
2595         if ((pr_res_holder->pr_res_type != type) ||
2596             (pr_res_holder->pr_res_scope != scope)) {
2597                 struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2598                 pr_err("SPC-3 PR RELEASE: Attempted to release"
2599                         " reservation from [%s]: %s with different TYPE "
2600                         "and/or SCOPE  while reservation already held by"
2601                         " [%s]: %s, returning RESERVATION_CONFLICT\n",
2602                         cmd->se_tfo->fabric_name,
2603                         se_sess->se_node_acl->initiatorname,
2604                         pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2605                         pr_res_holder->pr_reg_nacl->initiatorname);
2606 
2607                 spin_unlock(&dev->dev_reservation_lock);
2608                 ret = TCM_RESERVATION_CONFLICT;
2609                 goto out_put_pr_reg;
2610         }
2611         /*
2612          * In response to a persistent reservation release request from the
2613          * persistent reservation holder the device server shall perform a
2614          * release by doing the following as an uninterrupted series of actions:
2615          * a) Release the persistent reservation;
2616          * b) Not remove any registration(s);
2617          * c) If the released persistent reservation is a registrants only type
2618          * or all registrants type persistent reservation,
2619          *    the device server shall establish a unit attention condition for
2620          *    the initiator port associated with every regis-
2621          *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2622          *    RESERVE OUT command with RELEASE service action was received,
2623          *    with the additional sense code set to RESERVATIONS RELEASED; and
2624          * d) If the persistent reservation is of any other type, the device
2625          *    server shall not establish a unit attention condition.
2626          */
2627         __core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2628                                           pr_reg, 1, 0);
2629 
2630         spin_unlock(&dev->dev_reservation_lock);
2631 
2632         if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2633             (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2634             (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2635             (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2636                 /*
2637                  * If no UNIT ATTENTION conditions will be established for
2638                  * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2639                  * go ahead and check for APTPL=1 update+write below
2640                  */
2641                 goto write_aptpl;
2642         }
2643 
2644         spin_lock(&pr_tmpl->registration_lock);
2645         list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2646                         pr_reg_list) {
2647                 /*
2648                  * Do not establish a UNIT ATTENTION condition
2649                  * for the calling I_T Nexus
2650                  */
2651                 if (pr_reg_p == pr_reg)
2652                         continue;
2653 
2654                 target_ua_allocate_lun(pr_reg_p->pr_reg_nacl,
2655                                 pr_reg_p->pr_res_mapped_lun,
2656                                 0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2657         }
2658         spin_unlock(&pr_tmpl->registration_lock);
2659 
2660 write_aptpl:
2661         if (pr_tmpl->pr_aptpl_active)
2662                 core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2663 
2664 out_put_pr_reg:
2665         core_scsi3_put_pr_reg(pr_reg);
2666         return ret;
2667 }
2668 
2669 static sense_reason_t
2670 core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
2671 {
2672         struct se_device *dev = cmd->se_dev;
2673         struct se_node_acl *pr_reg_nacl;
2674         struct se_session *se_sess = cmd->se_sess;
2675         struct t10_reservation *pr_tmpl = &dev->t10_pr;
2676         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2677         u64 pr_res_mapped_lun = 0;
2678         int calling_it_nexus = 0;
2679         /*
2680          * Locate the existing *pr_reg via struct se_node_acl pointers
2681          */
2682         pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2683                         se_sess->se_node_acl, se_sess);
2684         if (!pr_reg_n) {
2685                 pr_err("SPC-3 PR: Unable to locate"
2686                         " PR_REGISTERED *pr_reg for CLEAR\n");
2687                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2688         }
2689         /*
2690          * From spc4r17 section 5.7.11.6, Clearing:
2691          *
2692          * Any application client may release the persistent reservation and
2693          * remove all registrations from a device server by issuing a
2694          * PERSISTENT RESERVE OUT command with CLEAR service action through a
2695          * registered I_T nexus with the following parameter:
2696          *
2697          *      a) RESERVATION KEY field set to the value of the reservation key
2698          *         that is registered with the logical unit for the I_T nexus.
2699          */
2700         if (res_key != pr_reg_n->pr_res_key) {
2701                 pr_err("SPC-3 PR REGISTER: Received"
2702                         " res_key: 0x%016Lx does not match"
2703                         " existing SA REGISTER res_key:"
2704                         " 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2705                 core_scsi3_put_pr_reg(pr_reg_n);
2706                 return TCM_RESERVATION_CONFLICT;
2707         }
2708         /*
2709          * a) Release the persistent reservation, if any;
2710          */
2711         spin_lock(&dev->dev_reservation_lock);
2712         pr_res_holder = dev->dev_pr_res_holder;
2713         if (pr_res_holder) {
2714                 struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2715                 __core_scsi3_complete_pro_release(dev, pr_res_nacl,
2716                                                   pr_res_holder, 0, 0);
2717         }
2718         spin_unlock(&dev->dev_reservation_lock);
2719         /*
2720          * b) Remove all registration(s) (see spc4r17 5.7.7);
2721          */
2722         spin_lock(&pr_tmpl->registration_lock);
2723         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2724                         &pr_tmpl->registration_list, pr_reg_list) {
2725 
2726                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2727                 pr_reg_nacl = pr_reg->pr_reg_nacl;
2728                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2729                 __core_scsi3_free_registration(dev, pr_reg, NULL,
2730                                         calling_it_nexus);
2731                 /*
2732                  * e) Establish a unit attention condition for the initiator
2733                  *    port associated with every registered I_T nexus other
2734                  *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2735                  *    command with CLEAR service action was received, with the
2736                  *    additional sense code set to RESERVATIONS PREEMPTED.
2737                  */
2738                 if (!calling_it_nexus)
2739                         target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun,
2740                                 0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2741         }
2742         spin_unlock(&pr_tmpl->registration_lock);
2743 
2744         pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2745                 cmd->se_tfo->fabric_name);
2746 
2747         core_scsi3_update_and_write_aptpl(cmd->se_dev, false);
2748 
2749         core_scsi3_pr_generation(dev);
2750         return 0;
2751 }
2752 
2753 static void __core_scsi3_complete_pro_preempt(
2754         struct se_device *dev,
2755         struct t10_pr_registration *pr_reg,
2756         struct list_head *preempt_and_abort_list,
2757         int type,
2758         int scope,
2759         enum preempt_type preempt_type)
2760 {
2761         struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2762         const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2763         char i_buf[PR_REG_ISID_ID_LEN];
2764 
2765         lockdep_assert_held(&dev->dev_reservation_lock);
2766 
2767         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2768         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2769         /*
2770          * Do an implicit RELEASE of the existing reservation.
2771          */
2772         if (dev->dev_pr_res_holder)
2773                 __core_scsi3_complete_pro_release(dev, nacl,
2774                                                   dev->dev_pr_res_holder, 0, 0);
2775 
2776         dev->dev_pr_res_holder = pr_reg;
2777         pr_reg->pr_res_holder = 1;
2778         pr_reg->pr_res_type = type;
2779         pr_reg->pr_res_scope = scope;
2780 
2781         pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2782                 " reservation holder TYPE: %s ALL_TG_PT: %d\n",
2783                 tfo->fabric_name, (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2784                 core_scsi3_pr_dump_type(type),
2785                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2786         pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2787                 tfo->fabric_name, (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2788                 nacl->initiatorname, i_buf);
2789         /*
2790          * For PREEMPT_AND_ABORT, add the preempting reservation's
2791          * struct t10_pr_registration to the list that will be compared
2792          * against received CDBs..
2793          */
2794         if (preempt_and_abort_list)
2795                 list_add_tail(&pr_reg->pr_reg_abort_list,
2796                                 preempt_and_abort_list);
2797 }
2798 
2799 static void core_scsi3_release_preempt_and_abort(
2800         struct list_head *preempt_and_abort_list,
2801         struct t10_pr_registration *pr_reg_holder)
2802 {
2803         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2804 
2805         list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2806                                 pr_reg_abort_list) {
2807 
2808                 list_del(&pr_reg->pr_reg_abort_list);
2809                 if (pr_reg_holder == pr_reg)
2810                         continue;
2811                 if (pr_reg->pr_res_holder) {
2812                         pr_warn("pr_reg->pr_res_holder still set\n");
2813                         continue;
2814                 }
2815 
2816                 pr_reg->pr_reg_deve = NULL;
2817                 pr_reg->pr_reg_nacl = NULL;
2818                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
2819         }
2820 }
2821 
2822 static sense_reason_t
2823 core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
2824                 u64 sa_res_key, enum preempt_type preempt_type)
2825 {
2826         struct se_device *dev = cmd->se_dev;
2827         struct se_node_acl *pr_reg_nacl;
2828         struct se_session *se_sess = cmd->se_sess;
2829         LIST_HEAD(preempt_and_abort_list);
2830         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2831         struct t10_reservation *pr_tmpl = &dev->t10_pr;
2832         u64 pr_res_mapped_lun = 0;
2833         int all_reg = 0, calling_it_nexus = 0;
2834         bool sa_res_key_unmatched = sa_res_key != 0;
2835         int prh_type = 0, prh_scope = 0;
2836 
2837         if (!se_sess)
2838                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2839 
2840         pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2841                                 se_sess);
2842         if (!pr_reg_n) {
2843                 pr_err("SPC-3 PR: Unable to locate"
2844                         " PR_REGISTERED *pr_reg for PREEMPT%s\n",
2845                         (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "");
2846                 return TCM_RESERVATION_CONFLICT;
2847         }
2848         if (pr_reg_n->pr_res_key != res_key) {
2849                 core_scsi3_put_pr_reg(pr_reg_n);
2850                 return TCM_RESERVATION_CONFLICT;
2851         }
2852         if (scope != PR_SCOPE_LU_SCOPE) {
2853                 pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2854                 core_scsi3_put_pr_reg(pr_reg_n);
2855                 return TCM_INVALID_PARAMETER_LIST;
2856         }
2857 
2858         spin_lock(&dev->dev_reservation_lock);
2859         pr_res_holder = dev->dev_pr_res_holder;
2860         if (pr_res_holder &&
2861            ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2862             (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
2863                 all_reg = 1;
2864 
2865         if (!all_reg && !sa_res_key) {
2866                 spin_unlock(&dev->dev_reservation_lock);
2867                 core_scsi3_put_pr_reg(pr_reg_n);
2868                 return TCM_INVALID_PARAMETER_LIST;
2869         }
2870         /*
2871          * From spc4r17, section 5.7.11.4.4 Removing Registrations:
2872          *
2873          * If the SERVICE ACTION RESERVATION KEY field does not identify a
2874          * persistent reservation holder or there is no persistent reservation
2875          * holder (i.e., there is no persistent reservation), then the device
2876          * server shall perform a preempt by doing the following in an
2877          * uninterrupted series of actions. (See below..)
2878          */
2879         if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
2880                 /*
2881                  * No existing or SA Reservation Key matching reservations..
2882                  *
2883                  * PROUT SA PREEMPT with All Registrant type reservations are
2884                  * allowed to be processed without a matching SA Reservation Key
2885                  */
2886                 spin_lock(&pr_tmpl->registration_lock);
2887                 list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2888                                 &pr_tmpl->registration_list, pr_reg_list) {
2889                         /*
2890                          * Removing of registrations in non all registrants
2891                          * type reservations without a matching SA reservation
2892                          * key.
2893                          *
2894                          * a) Remove the registrations for all I_T nexuses
2895                          *    specified by the SERVICE ACTION RESERVATION KEY
2896                          *    field;
2897                          * b) Ignore the contents of the SCOPE and TYPE fields;
2898                          * c) Process tasks as defined in 5.7.1; and
2899                          * d) Establish a unit attention condition for the
2900                          *    initiator port associated with every I_T nexus
2901                          *    that lost its registration other than the I_T
2902                          *    nexus on which the PERSISTENT RESERVE OUT command
2903                          *    was received, with the additional sense code set
2904                          *    to REGISTRATIONS PREEMPTED.
2905                          */
2906                         if (!all_reg) {
2907                                 if (pr_reg->pr_res_key != sa_res_key)
2908                                         continue;
2909                                 sa_res_key_unmatched = false;
2910 
2911                                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2912                                 pr_reg_nacl = pr_reg->pr_reg_nacl;
2913                                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2914                                 __core_scsi3_free_registration(dev, pr_reg,
2915                                         (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2916                                                 NULL, calling_it_nexus);
2917                         } else {
2918                                 /*
2919                                  * Case for any existing all registrants type
2920                                  * reservation, follow logic in spc4r17 section
2921                                  * 5.7.11.4 Preempting, Table 52 and Figure 7.
2922                                  *
2923                                  * For a ZERO SA Reservation key, release
2924                                  * all other registrations and do an implicit
2925                                  * release of active persistent reservation.
2926                                  *
2927                                  * For a non-ZERO SA Reservation key, only
2928                                  * release the matching reservation key from
2929                                  * registrations.
2930                                  */
2931                                 if ((sa_res_key) &&
2932                                      (pr_reg->pr_res_key != sa_res_key))
2933                                         continue;
2934                                 sa_res_key_unmatched = false;
2935 
2936                                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2937                                 if (calling_it_nexus)
2938                                         continue;
2939 
2940                                 pr_reg_nacl = pr_reg->pr_reg_nacl;
2941                                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2942                                 __core_scsi3_free_registration(dev, pr_reg,
2943                                         (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2944                                                 NULL, 0);
2945                         }
2946                         if (!calling_it_nexus)
2947                                 target_ua_allocate_lun(pr_reg_nacl,
2948                                         pr_res_mapped_lun, 0x2A,
2949                                         ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2950                 }
2951                 spin_unlock(&pr_tmpl->registration_lock);
2952                 /*
2953                  * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
2954                  * a PREEMPT AND ABORT service action sets the SERVICE ACTION
2955                  * RESERVATION KEY field to a value that does not match any
2956                  * registered reservation key, then the device server shall
2957                  * complete the command with RESERVATION CONFLICT status.
2958                  */
2959                 if (sa_res_key_unmatched) {
2960                         spin_unlock(&dev->dev_reservation_lock);
2961                         core_scsi3_put_pr_reg(pr_reg_n);
2962                         return TCM_RESERVATION_CONFLICT;
2963                 }
2964                 /*
2965                  * For an existing all registrants type reservation
2966                  * with a zero SA rservation key, preempt the existing
2967                  * reservation with the new PR type and scope.
2968                  */
2969                 if (pr_res_holder && all_reg && !(sa_res_key)) {
2970                         __core_scsi3_complete_pro_preempt(dev, pr_reg_n,
2971                                 (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2972                                 type, scope, preempt_type);
2973 
2974                         if (preempt_type == PREEMPT_AND_ABORT)
2975                                 core_scsi3_release_preempt_and_abort(
2976                                         &preempt_and_abort_list, pr_reg_n);
2977                 }
2978                 spin_unlock(&dev->dev_reservation_lock);
2979 
2980                 if (pr_tmpl->pr_aptpl_active)
2981                         core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2982 
2983                 core_scsi3_put_pr_reg(pr_reg_n);
2984                 core_scsi3_pr_generation(cmd->se_dev);
2985                 return 0;
2986         }
2987         /*
2988          * The PREEMPTing SA reservation key matches that of the
2989          * existing persistent reservation, first, we check if
2990          * we are preempting our own reservation.
2991          * From spc4r17, section 5.7.11.4.3 Preempting
2992          * persistent reservations and registration handling
2993          *
2994          * If an all registrants persistent reservation is not
2995          * present, it is not an error for the persistent
2996          * reservation holder to preempt itself (i.e., a
2997          * PERSISTENT RESERVE OUT with a PREEMPT service action
2998          * or a PREEMPT AND ABORT service action with the
2999          * SERVICE ACTION RESERVATION KEY value equal to the
3000          * persistent reservation holder's reservation key that
3001          * is received from the persistent reservation holder).
3002          * In that case, the device server shall establish the
3003          * new persistent reservation and maintain the
3004          * registration.
3005          */
3006         prh_type = pr_res_holder->pr_res_type;
3007         prh_scope = pr_res_holder->pr_res_scope;
3008         /*
3009          * If the SERVICE ACTION RESERVATION KEY field identifies a
3010          * persistent reservation holder (see 5.7.10), the device
3011          * server shall perform a preempt by doing the following as
3012          * an uninterrupted series of actions:
3013          *
3014          * a) Release the persistent reservation for the holder
3015          *    identified by the SERVICE ACTION RESERVATION KEY field;
3016          */
3017         if (pr_reg_n != pr_res_holder)
3018                 __core_scsi3_complete_pro_release(dev,
3019                                                   pr_res_holder->pr_reg_nacl,
3020                                                   dev->dev_pr_res_holder, 0, 0);
3021         /*
3022          * b) Remove the registrations for all I_T nexuses identified
3023          *    by the SERVICE ACTION RESERVATION KEY field, except the
3024          *    I_T nexus that is being used for the PERSISTENT RESERVE
3025          *    OUT command. If an all registrants persistent reservation
3026          *    is present and the SERVICE ACTION RESERVATION KEY field
3027          *    is set to zero, then all registrations shall be removed
3028          *    except for that of the I_T nexus that is being used for
3029          *    the PERSISTENT RESERVE OUT command;
3030          */
3031         spin_lock(&pr_tmpl->registration_lock);
3032         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3033                         &pr_tmpl->registration_list, pr_reg_list) {
3034 
3035                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3036                 if (calling_it_nexus)
3037                         continue;
3038 
3039                 if (pr_reg->pr_res_key != sa_res_key)
3040                         continue;
3041 
3042                 pr_reg_nacl = pr_reg->pr_reg_nacl;
3043                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3044                 __core_scsi3_free_registration(dev, pr_reg,
3045                                 (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3046                                 calling_it_nexus);
3047                 /*
3048                  * e) Establish a unit attention condition for the initiator
3049                  *    port associated with every I_T nexus that lost its
3050                  *    persistent reservation and/or registration, with the
3051                  *    additional sense code set to REGISTRATIONS PREEMPTED;
3052                  */
3053                 target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3054                                 ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3055         }
3056         spin_unlock(&pr_tmpl->registration_lock);
3057         /*
3058          * c) Establish a persistent reservation for the preempting
3059          *    I_T nexus using the contents of the SCOPE and TYPE fields;
3060          */
3061         __core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3062                         (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3063                         type, scope, preempt_type);
3064         /*
3065          * d) Process tasks as defined in 5.7.1;
3066          * e) See above..
3067          * f) If the type or scope has changed, then for every I_T nexus
3068          *    whose reservation key was not removed, except for the I_T
3069          *    nexus on which the PERSISTENT RESERVE OUT command was
3070          *    received, the device server shall establish a unit
3071          *    attention condition for the initiator port associated with
3072          *    that I_T nexus, with the additional sense code set to
3073          *    RESERVATIONS RELEASED. If the type or scope have not
3074          *    changed, then no unit attention condition(s) shall be
3075          *    established for this reason.
3076          */
3077         if ((prh_type != type) || (prh_scope != scope)) {
3078                 spin_lock(&pr_tmpl->registration_lock);
3079                 list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3080                                 &pr_tmpl->registration_list, pr_reg_list) {
3081 
3082                         calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3083                         if (calling_it_nexus)
3084                                 continue;
3085 
3086                         target_ua_allocate_lun(pr_reg->pr_reg_nacl,
3087                                         pr_reg->pr_res_mapped_lun, 0x2A,
3088                                         ASCQ_2AH_RESERVATIONS_RELEASED);
3089                 }
3090                 spin_unlock(&pr_tmpl->registration_lock);
3091         }
3092         spin_unlock(&dev->dev_reservation_lock);
3093         /*
3094          * Call LUN_RESET logic upon list of struct t10_pr_registration,
3095          * All received CDBs for the matching existing reservation and
3096          * registrations undergo ABORT_TASK logic.
3097          *
3098          * From there, core_scsi3_release_preempt_and_abort() will
3099          * release every registration in the list (which have already
3100          * been removed from the primary pr_reg list), except the
3101          * new persistent reservation holder, the calling Initiator Port.
3102          */
3103         if (preempt_type == PREEMPT_AND_ABORT) {
3104                 core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3105                 core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3106                                                 pr_reg_n);
3107         }
3108 
3109         if (pr_tmpl->pr_aptpl_active)
3110                 core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
3111 
3112         core_scsi3_put_pr_reg(pr_reg_n);
3113         core_scsi3_pr_generation(cmd->se_dev);
3114         return 0;
3115 }
3116 
3117 static sense_reason_t
3118 core_scsi3_emulate_pro_preempt(struct se_cmd *cmd, int type, int scope,
3119                 u64 res_key, u64 sa_res_key, enum preempt_type preempt_type)
3120 {
3121         switch (type) {
3122         case PR_TYPE_WRITE_EXCLUSIVE:
3123         case PR_TYPE_EXCLUSIVE_ACCESS:
3124         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3125         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3126         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3127         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3128                 return core_scsi3_pro_preempt(cmd, type, scope, res_key,
3129                                               sa_res_key, preempt_type);
3130         default:
3131                 pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3132                         " Type: 0x%02x\n", (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "", type);
3133                 return TCM_INVALID_CDB_FIELD;
3134         }
3135 }
3136 
3137 
3138 static sense_reason_t
3139 core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
3140                 u64 sa_res_key, int aptpl, int unreg)
3141 {
3142         struct se_session *se_sess = cmd->se_sess;
3143         struct se_device *dev = cmd->se_dev;
3144         struct se_dev_entry *dest_se_deve = NULL;
3145         struct se_lun *se_lun = cmd->se_lun, *tmp_lun;
3146         struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3147         struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3148         const struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3149         struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3150         struct t10_reservation *pr_tmpl = &dev->t10_pr;
3151         unsigned char *buf;
3152         const unsigned char *initiator_str;
3153         char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
3154         u32 tid_len, tmp_tid_len;
3155         int new_reg = 0, type, scope, matching_iname;
3156         sense_reason_t ret;
3157         unsigned short rtpi;
3158         unsigned char proto_ident;
3159 
3160         if (!se_sess || !se_lun) {
3161                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3162                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3163         }
3164 
3165         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3166         se_tpg = se_sess->se_tpg;
3167         tf_ops = se_tpg->se_tpg_tfo;
3168         /*
3169          * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3170          *      Register behaviors for a REGISTER AND MOVE service action
3171          *
3172          * Locate the existing *pr_reg via struct se_node_acl pointers
3173          */
3174         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3175                                 se_sess);
3176         if (!pr_reg) {
3177                 pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3178                         " *pr_reg for REGISTER_AND_MOVE\n");
3179                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3180         }
3181         /*
3182          * The provided reservation key much match the existing reservation key
3183          * provided during this initiator's I_T nexus registration.
3184          */
3185         if (res_key != pr_reg->pr_res_key) {
3186                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3187                         " res_key: 0x%016Lx does not match existing SA REGISTER"
3188                         " res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3189                 ret = TCM_RESERVATION_CONFLICT;
3190                 goto out_put_pr_reg;
3191         }
3192         /*
3193          * The service active reservation key needs to be non zero
3194          */
3195         if (!sa_res_key) {
3196                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3197                         " sa_res_key\n");
3198                 ret = TCM_INVALID_PARAMETER_LIST;
3199                 goto out_put_pr_reg;
3200         }
3201 
3202         /*
3203          * Determine the Relative Target Port Identifier where the reservation
3204          * will be moved to for the TransportID containing SCSI initiator WWN
3205          * information.
3206          */
3207         buf = transport_kmap_data_sg(cmd);
3208         if (!buf) {
3209                 ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3210                 goto out_put_pr_reg;
3211         }
3212 
3213         rtpi = get_unaligned_be16(&buf[18]);
3214         tid_len = get_unaligned_be32(&buf[20]);
3215         transport_kunmap_data_sg(cmd);
3216         buf = NULL;
3217 
3218         if ((tid_len + 24) != cmd->data_length) {
3219                 pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3220                         " does not equal CDB data_length: %u\n", tid_len,
3221                         cmd->data_length);
3222                 ret = TCM_INVALID_PARAMETER_LIST;
3223                 goto out_put_pr_reg;
3224         }
3225 
3226         spin_lock(&dev->se_port_lock);
3227         list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
3228                 if (tmp_lun->lun_rtpi != rtpi)
3229                         continue;
3230                 dest_se_tpg = tmp_lun->lun_tpg;
3231                 dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3232                 if (!dest_tf_ops)
3233                         continue;
3234 
3235                 atomic_inc_mb(&dest_se_tpg->tpg_pr_ref_count);
3236                 spin_unlock(&dev->se_port_lock);
3237 
3238                 if (core_scsi3_tpg_depend_item(dest_se_tpg)) {
3239                         pr_err("core_scsi3_tpg_depend_item() failed"
3240                                 " for dest_se_tpg\n");
3241                         atomic_dec_mb(&dest_se_tpg->tpg_pr_ref_count);
3242                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3243                         goto out_put_pr_reg;
3244                 }
3245 
3246                 spin_lock(&dev->se_port_lock);
3247                 break;
3248         }
3249         spin_unlock(&dev->se_port_lock);
3250 
3251         if (!dest_se_tpg || !dest_tf_ops) {
3252                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3253                         " fabric ops from Relative Target Port Identifier:"
3254                         " %hu\n", rtpi);
3255                 ret = TCM_INVALID_PARAMETER_LIST;
3256                 goto out_put_pr_reg;
3257         }
3258 
3259         buf = transport_kmap_data_sg(cmd);
3260         if (!buf) {
3261                 ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3262                 goto out_put_pr_reg;
3263         }
3264         proto_ident = (buf[24] & 0x0f);
3265 
3266         pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3267                         " 0x%02x\n", proto_ident);
3268 
3269         if (proto_ident != dest_se_tpg->proto_id) {
3270                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3271                         " proto_ident: 0x%02x does not match ident: 0x%02x"
3272                         " from fabric: %s\n", proto_ident,
3273                         dest_se_tpg->proto_id,
3274                         dest_tf_ops->fabric_name);
3275                 ret = TCM_INVALID_PARAMETER_LIST;
3276                 goto out;
3277         }
3278         initiator_str = target_parse_pr_out_transport_id(dest_se_tpg,
3279                         &buf[24], &tmp_tid_len, &iport_ptr);
3280         if (!initiator_str) {
3281                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3282                         " initiator_str from Transport ID\n");
3283                 ret = TCM_INVALID_PARAMETER_LIST;
3284                 goto out;
3285         }
3286 
3287         transport_kunmap_data_sg(cmd);
3288         buf = NULL;
3289 
3290         pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3291                 " %s\n", dest_tf_ops->fabric_name, (iport_ptr != NULL) ?
3292                 "port" : "device", initiator_str, (iport_ptr != NULL) ?
3293                 iport_ptr : "");
3294         /*
3295          * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3296          * action specifies a TransportID that is the same as the initiator port
3297          * of the I_T nexus for the command received, then the command shall
3298          * be terminated with CHECK CONDITION status, with the sense key set to
3299          * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3300          * IN PARAMETER LIST.
3301          */
3302         pr_reg_nacl = pr_reg->pr_reg_nacl;
3303         matching_iname = (!strcmp(initiator_str,
3304                                   pr_reg_nacl->initiatorname)) ? 1 : 0;
3305         if (!matching_iname)
3306                 goto after_iport_check;
3307 
3308         if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3309                 pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3310                         " matches: %s on received I_T Nexus\n", initiator_str,
3311                         pr_reg_nacl->initiatorname);
3312                 ret = TCM_INVALID_PARAMETER_LIST;
3313                 goto out;
3314         }
3315         if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3316                 pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3317                         " matches: %s %s on received I_T Nexus\n",
3318                         initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3319                         pr_reg->pr_reg_isid);
3320                 ret = TCM_INVALID_PARAMETER_LIST;
3321                 goto out;
3322         }
3323 after_iport_check:
3324         /*
3325          * Locate the destination struct se_node_acl from the received Transport ID
3326          */
3327         mutex_lock(&dest_se_tpg->acl_node_mutex);
3328         dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3329                                 initiator_str);
3330         if (dest_node_acl)
3331                 atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
3332         mutex_unlock(&dest_se_tpg->acl_node_mutex);
3333 
3334         if (!dest_node_acl) {
3335                 pr_err("Unable to locate %s dest_node_acl for"
3336                         " TransportID%s\n", dest_tf_ops->fabric_name,
3337                         initiator_str);
3338                 ret = TCM_INVALID_PARAMETER_LIST;
3339                 goto out;
3340         }
3341 
3342         if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
3343                 pr_err("core_scsi3_nodeacl_depend_item() for"
3344                         " dest_node_acl\n");
3345                 atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
3346                 dest_node_acl = NULL;
3347                 ret = TCM_INVALID_PARAMETER_LIST;
3348                 goto out;
3349         }
3350 
3351         pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3352                 " %s from TransportID\n", dest_tf_ops->fabric_name,
3353                 dest_node_acl->initiatorname);
3354 
3355         /*
3356          * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3357          * PORT IDENTIFIER.
3358          */
3359         dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3360         if (!dest_se_deve) {
3361                 pr_err("Unable to locate %s dest_se_deve from RTPI:"
3362                         " %hu\n",  dest_tf_ops->fabric_name, rtpi);
3363                 ret = TCM_INVALID_PARAMETER_LIST;
3364                 goto out;
3365         }
3366 
3367         if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
3368                 pr_err("core_scsi3_lunacl_depend_item() failed\n");
3369                 kref_put(&dest_se_deve->pr_kref, target_pr_kref_release);
3370                 dest_se_deve = NULL;
3371                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3372                 goto out;
3373         }
3374 
3375         pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3376                 " ACL for dest_se_deve->mapped_lun: %llu\n",
3377                 dest_tf_ops->fabric_name, dest_node_acl->initiatorname,
3378                 dest_se_deve->mapped_lun);
3379 
3380         /*
3381          * A persistent reservation needs to already existing in order to
3382          * successfully complete the REGISTER_AND_MOVE service action..
3383          */
3384         spin_lock(&dev->dev_reservation_lock);
3385         pr_res_holder = dev->dev_pr_res_holder;
3386         if (!pr_res_holder) {
3387                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3388                         " currently held\n");
3389                 spin_unlock(&dev->dev_reservation_lock);
3390                 ret = TCM_INVALID_CDB_FIELD;
3391                 goto out;
3392         }
3393         /*
3394          * The received on I_T Nexus must be the reservation holder.
3395          *
3396          * From spc4r17 section 5.7.8  Table 50 --
3397          *      Register behaviors for a REGISTER AND MOVE service action
3398          */
3399         if (!is_reservation_holder(pr_res_holder, pr_reg)) {
3400                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3401                         " Nexus is not reservation holder\n");
3402                 spin_unlock(&dev->dev_reservation_lock);
3403                 ret = TCM_RESERVATION_CONFLICT;
3404                 goto out;
3405         }
3406         /*
3407          * From spc4r17 section 5.7.8: registering and moving reservation
3408          *
3409          * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3410          * action is received and the established persistent reservation is a
3411          * Write Exclusive - All Registrants type or Exclusive Access -
3412          * All Registrants type reservation, then the command shall be completed
3413          * with RESERVATION CONFLICT status.
3414          */
3415         if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3416             (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3417                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3418                         " reservation for type: %s\n",
3419                         core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3420                 spin_unlock(&dev->dev_reservation_lock);
3421                 ret = TCM_RESERVATION_CONFLICT;
3422                 goto out;
3423         }
3424         pr_res_nacl = pr_res_holder->pr_reg_nacl;
3425         /*
3426          * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3427          */
3428         type = pr_res_holder->pr_res_type;
3429         scope = pr_res_holder->pr_res_type;
3430         /*
3431          * c) Associate the reservation key specified in the SERVICE ACTION
3432          *    RESERVATION KEY field with the I_T nexus specified as the
3433          *    destination of the register and move, where:
3434          *    A) The I_T nexus is specified by the TransportID and the
3435          *       RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3436          *    B) Regardless of the TransportID format used, the association for
3437          *       the initiator port is based on either the initiator port name
3438          *       (see 3.1.71) on SCSI transport protocols where port names are
3439          *       required or the initiator port identifier (see 3.1.70) on SCSI
3440          *       transport protocols where port names are not required;
3441          * d) Register the reservation key specified in the SERVICE ACTION
3442          *    RESERVATION KEY field;
3443          * e) Retain the reservation key specified in the SERVICE ACTION
3444          *    RESERVATION KEY field and associated information;
3445          *
3446          * Also, It is not an error for a REGISTER AND MOVE service action to
3447          * register an I_T nexus that is already registered with the same
3448          * reservation key or a different reservation key.
3449          */
3450         dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3451                                         iport_ptr);
3452         if (!dest_pr_reg) {
3453                 struct se_lun *dest_lun = rcu_dereference_check(dest_se_deve->se_lun,
3454                                 kref_read(&dest_se_deve->pr_kref) != 0);
3455 
3456                 spin_unlock(&dev->dev_reservation_lock);
3457                 if (core_scsi3_alloc_registration(cmd->se_dev, dest_node_acl,
3458                                         dest_lun, dest_se_deve, dest_se_deve->mapped_lun,
3459                                         iport_ptr, sa_res_key, 0, aptpl, 2, 1)) {
3460                         ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3461                         goto out;
3462                 }
3463                 spin_lock(&dev->dev_reservation_lock);
3464                 dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3465                                                 iport_ptr);
3466                 new_reg = 1;
3467         }
3468         /*
3469          * f) Release the persistent reservation for the persistent reservation
3470          *    holder (i.e., the I_T nexus on which the
3471          */
3472         __core_scsi3_complete_pro_release(dev, pr_res_nacl,
3473                                           dev->dev_pr_res_holder, 0, 0);
3474         /*
3475          * g) Move the persistent reservation to the specified I_T nexus using
3476          *    the same scope and type as the persistent reservation released in
3477          *    item f); and
3478          */
3479         dev->dev_pr_res_holder = dest_pr_reg;
3480         dest_pr_reg->pr_res_holder = 1;
3481         dest_pr_reg->pr_res_type = type;
3482         pr_reg->pr_res_scope = scope;
3483         core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
3484         /*
3485          * Increment PRGeneration for existing registrations..
3486          */
3487         if (!new_reg)
3488                 dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3489         spin_unlock(&dev->dev_reservation_lock);
3490 
3491         pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3492                 " created new reservation holder TYPE: %s on object RTPI:"
3493                 " %hu  PRGeneration: 0x%08x\n", dest_tf_ops->fabric_name,
3494                 core_scsi3_pr_dump_type(type), rtpi,
3495                 dest_pr_reg->pr_res_generation);
3496         pr_debug("SPC-3 PR Successfully moved reservation from"
3497                 " %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3498                 tf_ops->fabric_name, pr_reg_nacl->initiatorname,
3499                 i_buf, dest_tf_ops->fabric_name,
3500                 dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3501                 iport_ptr : "");
3502         /*
3503          * It is now safe to release configfs group dependencies for destination
3504          * of Transport ID Initiator Device/Port Identifier
3505          */
3506         core_scsi3_lunacl_undepend_item(dest_se_deve);
3507         core_scsi3_nodeacl_undepend_item(dest_node_acl);
3508         core_scsi3_tpg_undepend_item(dest_se_tpg);
3509         /*
3510          * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3511          * nexus on which PERSISTENT RESERVE OUT command was received.
3512          */
3513         if (unreg) {
3514                 spin_lock(&pr_tmpl->registration_lock);
3515                 __core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3516                 spin_unlock(&pr_tmpl->registration_lock);
3517         } else
3518                 core_scsi3_put_pr_reg(pr_reg);
3519 
3520         core_scsi3_update_and_write_aptpl(cmd->se_dev, aptpl);
3521 
3522         core_scsi3_put_pr_reg(dest_pr_reg);
3523         return 0;
3524 out:
3525         if (buf)
3526                 transport_kunmap_data_sg(cmd);
3527         if (dest_se_deve)
3528                 core_scsi3_lunacl_undepend_item(dest_se_deve);
3529         if (dest_node_acl)
3530                 core_scsi3_nodeacl_undepend_item(dest_node_acl);
3531         core_scsi3_tpg_undepend_item(dest_se_tpg);
3532 
3533 out_put_pr_reg:
3534         core_scsi3_put_pr_reg(pr_reg);
3535         return ret;
3536 }
3537 
3538 /*
3539  * See spc4r17 section 6.14 Table 170
3540  */
3541 sense_reason_t
3542 target_scsi3_emulate_pr_out(struct se_cmd *cmd)
3543 {
3544         struct se_device *dev = cmd->se_dev;
3545         unsigned char *cdb = &cmd->t_task_cdb[0];
3546         unsigned char *buf;
3547         u64 res_key, sa_res_key;
3548         int sa, scope, type, aptpl;
3549         int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3550         sense_reason_t ret;
3551 
3552         /*
3553          * Following spc2r20 5.5.1 Reservations overview:
3554          *
3555          * If a logical unit has been reserved by any RESERVE command and is
3556          * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3557          * PERSISTENT RESERVE OUT commands shall conflict regardless of
3558          * initiator or service action and shall terminate with a RESERVATION
3559          * CONFLICT status.
3560          */
3561         if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
3562                 pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3563                         " SPC-2 reservation is held, returning"
3564                         " RESERVATION_CONFLICT\n");
3565                 return TCM_RESERVATION_CONFLICT;
3566         }
3567 
3568         /*
3569          * FIXME: A NULL struct se_session pointer means an this is not coming from
3570          * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3571          */
3572         if (!cmd->se_sess)
3573                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3574 
3575         if (cmd->data_length < 24) {
3576                 pr_warn("SPC-PR: Received PR OUT parameter list"
3577                         " length too small: %u\n", cmd->data_length);
3578                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
3579         }
3580 
3581         /*
3582          * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3583          */
3584         sa = (cdb[1] & 0x1f);
3585         scope = (cdb[2] & 0xf0);
3586         type = (cdb[2] & 0x0f);
3587 
3588         buf = transport_kmap_data_sg(cmd);
3589         if (!buf)
3590                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3591 
3592         /*
3593          * From PERSISTENT_RESERVE_OUT parameter list (payload)
3594          */
3595         res_key = get_unaligned_be64(&buf[0]);
3596         sa_res_key = get_unaligned_be64(&buf[8]);
3597         /*
3598          * REGISTER_AND_MOVE uses a different SA parameter list containing
3599          * SCSI TransportIDs.
3600          */
3601         if (sa != PRO_REGISTER_AND_MOVE) {
3602                 spec_i_pt = (buf[20] & 0x08);
3603                 all_tg_pt = (buf[20] & 0x04);
3604                 aptpl = (buf[20] & 0x01);
3605         } else {
3606                 aptpl = (buf[17] & 0x01);
3607                 unreg = (buf[17] & 0x02);
3608         }
3609         /*
3610          * If the backend device has been configured to force APTPL metadata
3611          * write-out, go ahead and propigate aptpl=1 down now.
3612          */
3613         if (dev->dev_attrib.force_pr_aptpl)
3614                 aptpl = 1;
3615 
3616         transport_kunmap_data_sg(cmd);
3617         buf = NULL;
3618 
3619         /*
3620          * SPEC_I_PT=1 is only valid for Service action: REGISTER
3621          */
3622         if (spec_i_pt && (sa != PRO_REGISTER))
3623                 return TCM_INVALID_PARAMETER_LIST;
3624 
3625         /*
3626          * From spc4r17 section 6.14:
3627          *
3628          * If the SPEC_I_PT bit is set to zero, the service action is not
3629          * REGISTER AND MOVE, and the parameter list length is not 24, then
3630          * the command shall be terminated with CHECK CONDITION status, with
3631          * the sense key set to ILLEGAL REQUEST, and the additional sense
3632          * code set to PARAMETER LIST LENGTH ERROR.
3633          */
3634         if (!spec_i_pt && (sa != PRO_REGISTER_AND_MOVE) &&
3635             (cmd->data_length != 24)) {
3636                 pr_warn("SPC-PR: Received PR OUT illegal parameter"
3637                         " list length: %u\n", cmd->data_length);
3638                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
3639         }
3640 
3641         /*
3642          * (core_scsi3_emulate_pro_* function parameters
3643          * are defined by spc4r17 Table 174:
3644          * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3645          */
3646         switch (sa) {
3647         case PRO_REGISTER:
3648                 ret = core_scsi3_emulate_pro_register(cmd,
3649                         res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER);
3650                 break;
3651         case PRO_RESERVE:
3652                 ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3653                 break;
3654         case PRO_RELEASE:
3655                 ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3656                 break;
3657         case PRO_CLEAR:
3658                 ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3659                 break;
3660         case PRO_PREEMPT:
3661                 ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3662                                         res_key, sa_res_key, PREEMPT);
3663                 break;
3664         case PRO_PREEMPT_AND_ABORT:
3665                 ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3666                                         res_key, sa_res_key, PREEMPT_AND_ABORT);
3667                 break;
3668         case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3669                 ret = core_scsi3_emulate_pro_register(cmd,
3670                         0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER_AND_IGNORE_EXISTING_KEY);
3671                 break;
3672         case PRO_REGISTER_AND_MOVE:
3673                 ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3674                                 sa_res_key, aptpl, unreg);
3675                 break;
3676         default:
3677                 pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3678                         " action: 0x%02x\n", sa);
3679                 return TCM_INVALID_CDB_FIELD;
3680         }
3681 
3682         if (!ret)
3683                 target_complete_cmd(cmd, GOOD);
3684         return ret;
3685 }
3686 
3687 /*
3688  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3689  *
3690  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3691  */
3692 static sense_reason_t
3693 core_scsi3_pri_read_keys(struct se_cmd *cmd)
3694 {
3695         struct se_device *dev = cmd->se_dev;
3696         struct t10_pr_registration *pr_reg;
3697         unsigned char *buf;
3698         u32 add_len = 0, off = 8;
3699 
3700         if (cmd->data_length < 8) {
3701                 pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3702                         " too small\n", cmd->data_length);
3703                 return TCM_INVALID_CDB_FIELD;
3704         }
3705 
3706         buf = transport_kmap_data_sg(cmd);
3707         if (!buf)
3708                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3709 
3710         put_unaligned_be32(dev->t10_pr.pr_generation, buf);
3711 
3712         spin_lock(&dev->t10_pr.registration_lock);
3713         list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
3714                         pr_reg_list) {
3715                 /*
3716                  * Check for overflow of 8byte PRI READ_KEYS payload and
3717                  * next reservation key list descriptor.
3718                  */
3719                 if (off + 8 <= cmd->data_length) {
3720                         put_unaligned_be64(pr_reg->pr_res_key, &buf[off]);
3721                         off += 8;
3722                 }
3723                 /*
3724                  * SPC5r17: 6.16.2 READ KEYS service action
3725                  * The ADDITIONAL LENGTH field indicates the number of bytes in
3726                  * the Reservation key list. The contents of the ADDITIONAL
3727                  * LENGTH field are not altered based on the allocation length
3728                  */
3729                 add_len += 8;
3730         }
3731         spin_unlock(&dev->t10_pr.registration_lock);
3732 
3733         put_unaligned_be32(add_len, &buf[4]);
3734 
3735         transport_kunmap_data_sg(cmd);
3736 
3737         return 0;
3738 }
3739 
3740 /*
3741  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3742  *
3743  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3744  */
3745 static sense_reason_t
3746 core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3747 {
3748         struct se_device *dev = cmd->se_dev;
3749         struct t10_pr_registration *pr_reg;
3750         unsigned char *buf;
3751         u64 pr_res_key;
3752         u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
3753 
3754         if (cmd->data_length < 8) {
3755                 pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3756                         " too small\n", cmd->data_length);
3757                 return TCM_INVALID_CDB_FIELD;
3758         }
3759 
3760         buf = transport_kmap_data_sg(cmd);
3761         if (!buf)
3762                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3763 
3764         put_unaligned_be32(dev->t10_pr.pr_generation, &buf[0]);
3765 
3766         spin_lock(&dev->dev_reservation_lock);
3767         pr_reg = dev->dev_pr_res_holder;
3768         if (pr_reg) {
3769                 /*
3770                  * Set the hardcoded Additional Length
3771                  */
3772                 put_unaligned_be32(add_len, &buf[4]);
3773 
3774                 if (cmd->data_length < 22)
3775                         goto err;
3776 
3777                 /*
3778                  * Set the Reservation key.
3779                  *
3780                  * From spc4r17, section 5.7.10:
3781                  * A persistent reservation holder has its reservation key
3782                  * returned in the parameter data from a PERSISTENT
3783                  * RESERVE IN command with READ RESERVATION service action as
3784                  * follows:
3785                  * a) For a persistent reservation of the type Write Exclusive
3786                  *    - All Registrants or Exclusive Access ­ All Regitrants,
3787                  *      the reservation key shall be set to zero; or
3788                  * b) For all other persistent reservation types, the
3789                  *    reservation key shall be set to the registered
3790                  *    reservation key for the I_T nexus that holds the
3791                  *    persistent reservation.
3792                  */
3793                 if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3794                     (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3795                         pr_res_key = 0;
3796                 else
3797                         pr_res_key = pr_reg->pr_res_key;
3798 
3799                 put_unaligned_be64(pr_res_key, &buf[8]);
3800                 /*
3801                  * Set the SCOPE and TYPE
3802                  */
3803                 buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3804                           (pr_reg->pr_res_type & 0x0f);
3805         }
3806 
3807 err:
3808         spin_unlock(&dev->dev_reservation_lock);
3809         transport_kunmap_data_sg(cmd);
3810 
3811         return 0;
3812 }
3813 
3814 /*
3815  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3816  *
3817  * See spc4r17 section 6.13.4 Table 165
3818  */
3819 static sense_reason_t
3820 core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3821 {
3822         struct se_device *dev = cmd->se_dev;
3823         struct t10_reservation *pr_tmpl = &dev->t10_pr;
3824         unsigned char *buf;
3825         u16 add_len = 8; /* Hardcoded to 8. */
3826 
3827         if (cmd->data_length < 6) {
3828                 pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
3829                         " %u too small\n", cmd->data_length);
3830                 return TCM_INVALID_CDB_FIELD;
3831         }
3832 
3833         buf = transport_kmap_data_sg(cmd);
3834         if (!buf)
3835                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3836 
3837         put_unaligned_be16(add_len, &buf[0]);
3838         buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
3839         buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
3840         buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
3841         buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
3842         /*
3843          * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
3844          * set the TMV: Task Mask Valid bit.
3845          */
3846         buf[3] |= 0x80;
3847         /*
3848          * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
3849          */
3850         buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
3851         /*
3852          * PTPL_A: Persistence across Target Power Loss Active bit
3853          */
3854         if (pr_tmpl->pr_aptpl_active)
3855                 buf[3] |= 0x01;
3856         /*
3857          * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
3858          */
3859         buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3860         buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
3861         buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
3862         buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
3863         buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
3864         buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3865 
3866         transport_kunmap_data_sg(cmd);
3867 
3868         return 0;
3869 }
3870 
3871 /*
3872  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
3873  *
3874  * See spc4r17 section 6.13.5 Table 168 and 169
3875  */
3876 static sense_reason_t
3877 core_scsi3_pri_read_full_status(struct se_cmd *cmd)
3878 {
3879         struct se_device *dev = cmd->se_dev;
3880         struct se_node_acl *se_nacl;
3881         struct se_portal_group *se_tpg;
3882         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
3883         struct t10_reservation *pr_tmpl = &dev->t10_pr;
3884         unsigned char *buf;
3885         u32 add_desc_len = 0, add_len = 0;
3886         u32 off = 8; /* off into first Full Status descriptor */
3887         int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
3888         int exp_desc_len, desc_len;
3889         bool all_reg = false;
3890 
3891         if (cmd->data_length < 8) {
3892                 pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
3893                         " too small\n", cmd->data_length);
3894                 return TCM_INVALID_CDB_FIELD;
3895         }
3896 
3897         buf = transport_kmap_data_sg(cmd);
3898         if (!buf)
3899                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3900 
3901         put_unaligned_be32(dev->t10_pr.pr_generation, &buf[0]);
3902 
3903         spin_lock(&dev->dev_reservation_lock);
3904         if (dev->dev_pr_res_holder) {
3905                 struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
3906 
3907                 if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
3908                     pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
3909                         all_reg = true;
3910                         pr_res_type = pr_holder->pr_res_type;
3911                         pr_res_scope = pr_holder->pr_res_scope;
3912                 }
3913         }
3914         spin_unlock(&dev->dev_reservation_lock);
3915 
3916         spin_lock(&pr_tmpl->registration_lock);
3917         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3918                         &pr_tmpl->registration_list, pr_reg_list) {
3919 
3920                 se_nacl = pr_reg->pr_reg_nacl;
3921                 se_tpg = pr_reg->pr_reg_nacl->se_tpg;
3922                 add_desc_len = 0;
3923 
3924                 atomic_inc_mb(&pr_reg->pr_res_holders);
3925                 spin_unlock(&pr_tmpl->registration_lock);
3926                 /*
3927                  * Determine expected length of $FABRIC_MOD specific
3928                  * TransportID full status descriptor..
3929                  */
3930                 exp_desc_len = target_get_pr_transport_id_len(se_nacl, pr_reg,
3931                                         &format_code);
3932                 if (exp_desc_len < 0 ||
3933                     exp_desc_len + add_len > cmd->data_length) {
3934                         pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
3935                                 " out of buffer: %d\n", cmd->data_length);
3936                         spin_lock(&pr_tmpl->registration_lock);
3937                         atomic_dec_mb(&pr_reg->pr_res_holders);
3938                         break;
3939                 }
3940                 /*
3941                  * Set RESERVATION KEY
3942                  */
3943                 put_unaligned_be64(pr_reg->pr_res_key, &buf[off]);
3944                 off += 8;
3945                 off += 4; /* Skip Over Reserved area */
3946 
3947                 /*
3948                  * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
3949                  */
3950                 if (pr_reg->pr_reg_all_tg_pt)
3951                         buf[off] = 0x02;
3952                 /*
3953                  * The struct se_lun pointer will be present for the
3954                  * reservation holder for PR_HOLDER bit.
3955                  *
3956                  * Also, if this registration is the reservation
3957                  * holder or there is an All Registrants reservation
3958                  * active, fill in SCOPE and TYPE in the next byte.
3959                  */
3960                 if (pr_reg->pr_res_holder) {
3961                         buf[off++] |= 0x01;
3962                         buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
3963                                      (pr_reg->pr_res_type & 0x0f);
3964                 } else if (all_reg) {
3965                         buf[off++] |= 0x01;
3966                         buf[off++] = (pr_res_scope & 0xf0) |
3967                                      (pr_res_type & 0x0f);
3968                 } else {
3969                         off += 2;
3970                 }
3971 
3972                 off += 4; /* Skip over reserved area */
3973                 /*
3974                  * From spc4r17 6.3.15:
3975                  *
3976                  * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
3977                  * IDENTIFIER field contains the relative port identifier (see
3978                  * 3.1.120) of the target port that is part of the I_T nexus
3979                  * described by this full status descriptor. If the ALL_TG_PT
3980                  * bit is set to one, the contents of the RELATIVE TARGET PORT
3981                  * IDENTIFIER field are not defined by this standard.
3982                  */
3983                 if (!pr_reg->pr_reg_all_tg_pt) {
3984                         u16 sep_rtpi = pr_reg->tg_pt_sep_rtpi;
3985 
3986                         put_unaligned_be16(sep_rtpi, &buf[off]);
3987                         off += 2;
3988                 } else
3989                         off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */
3990 
3991                 buf[off+4] = se_tpg->proto_id;
3992 
3993                 /*
3994                  * Now, have the $FABRIC_MOD fill in the transport ID.
3995                  */
3996                 desc_len = target_get_pr_transport_id(se_nacl, pr_reg,
3997                                 &format_code, &buf[off+4]);
3998 
3999                 spin_lock(&pr_tmpl->registration_lock);
4000                 atomic_dec_mb(&pr_reg->pr_res_holders);
4001 
4002                 if (desc_len < 0)
4003                         break;
4004                 /*
4005                  * Set the ADDITIONAL DESCRIPTOR LENGTH
4006                  */
4007                 put_unaligned_be32(desc_len, &buf[off]);
4008                 off += 4;
4009                 /*
4010                  * Size of full desctipor header minus TransportID
4011                  * containing $FABRIC_MOD specific) initiator device/port
4012                  * WWN information.
4013                  *
4014                  *  See spc4r17 Section 6.13.5 Table 169
4015                  */
4016                 add_desc_len = (24 + desc_len);
4017 
4018                 off += desc_len;
4019                 add_len += add_desc_len;
4020         }
4021         spin_unlock(&pr_tmpl->registration_lock);
4022         /*
4023          * Set ADDITIONAL_LENGTH
4024          */
4025         put_unaligned_be32(add_len, &buf[4]);
4026 
4027         transport_kunmap_data_sg(cmd);
4028 
4029         return 0;
4030 }
4031 
4032 sense_reason_t
4033 target_scsi3_emulate_pr_in(struct se_cmd *cmd)
4034 {
4035         sense_reason_t ret;
4036 
4037         /*
4038          * Following spc2r20 5.5.1 Reservations overview:
4039          *
4040          * If a logical unit has been reserved by any RESERVE command and is
4041          * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4042          * PERSISTENT RESERVE OUT commands shall conflict regardless of
4043          * initiator or service action and shall terminate with a RESERVATION
4044          * CONFLICT status.
4045          */
4046         if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
4047                 pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4048                         " SPC-2 reservation is held, returning"
4049                         " RESERVATION_CONFLICT\n");
4050                 return TCM_RESERVATION_CONFLICT;
4051         }
4052 
4053         switch (cmd->t_task_cdb[1] & 0x1f) {
4054         case PRI_READ_KEYS:
4055                 ret = core_scsi3_pri_read_keys(cmd);
4056                 break;
4057         case PRI_READ_RESERVATION:
4058                 ret = core_scsi3_pri_read_reservation(cmd);
4059                 break;
4060         case PRI_REPORT_CAPABILITIES:
4061                 ret = core_scsi3_pri_report_capabilities(cmd);
4062                 break;
4063         case PRI_READ_FULL_STATUS:
4064                 ret = core_scsi3_pri_read_full_status(cmd);
4065                 break;
4066         default:
4067                 pr_err("Unknown PERSISTENT_RESERVE_IN service"
4068                         " action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4069                 return TCM_INVALID_CDB_FIELD;
4070         }
4071 
4072         if (!ret)
4073                 target_complete_cmd(cmd, GOOD);
4074         return ret;
4075 }
4076 
4077 sense_reason_t
4078 target_check_reservation(struct se_cmd *cmd)
4079 {
4080         struct se_device *dev = cmd->se_dev;
4081         sense_reason_t ret;
4082 
4083         if (!cmd->se_sess)
4084                 return 0;
4085         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
4086                 return 0;
4087         if (!dev->dev_attrib.emulate_pr)
4088                 return 0;
4089         if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_PGR)
4090                 return 0;
4091 
4092         spin_lock(&dev->dev_reservation_lock);
4093         if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
4094                 ret = target_scsi2_reservation_check(cmd);
4095         else
4096                 ret = target_scsi3_pr_reservation_check(cmd);
4097         spin_unlock(&dev->dev_reservation_lock);
4098 
4099         return ret;
4100 }

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