target: Update QUEUE ALGORITHM MODIFIER control page default
[pandora-kernel.git] / drivers / target / target_core_pr.c
1 /*******************************************************************************
2  * Filename:  target_core_pr.c
3  *
4  * This file contains SPC-3 compliant persistent reservations and
5  * legacy SPC-2 reservations with compatible reservation handling (CRH=1)
6  *
7  * Copyright (c) 2009, 2010 Rising Tide Systems
8  * Copyright (c) 2009, 2010 Linux-iSCSI.org
9  *
10  * Nicholas A. Bellinger <nab@kernel.org>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25  *
26  ******************************************************************************/
27
28 #include <linux/version.h>
29 #include <linux/slab.h>
30 #include <linux/spinlock.h>
31 #include <linux/list.h>
32 #include <scsi/scsi.h>
33 #include <scsi/scsi_cmnd.h>
34 #include <asm/unaligned.h>
35
36 #include <target/target_core_base.h>
37 #include <target/target_core_device.h>
38 #include <target/target_core_tmr.h>
39 #include <target/target_core_tpg.h>
40 #include <target/target_core_transport.h>
41 #include <target/target_core_fabric_ops.h>
42 #include <target/target_core_configfs.h>
43
44 #include "target_core_hba.h"
45 #include "target_core_pr.h"
46 #include "target_core_ua.h"
47
48 /*
49  * Used for Specify Initiator Ports Capable Bit (SPEC_I_PT)
50  */
51 struct pr_transport_id_holder {
52         int dest_local_nexus;
53         struct t10_pr_registration *dest_pr_reg;
54         struct se_portal_group *dest_tpg;
55         struct se_node_acl *dest_node_acl;
56         struct se_dev_entry *dest_se_deve;
57         struct list_head dest_list;
58 };
59
60 int core_pr_dump_initiator_port(
61         struct t10_pr_registration *pr_reg,
62         char *buf,
63         u32 size)
64 {
65         if (!pr_reg->isid_present_at_reg)
66                 return 0;
67
68         snprintf(buf, size, ",i,0x%s", &pr_reg->pr_reg_isid[0]);
69         return 1;
70 }
71
72 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
73                         struct t10_pr_registration *, int);
74
75 static int core_scsi2_reservation_seq_non_holder(
76         struct se_cmd *cmd,
77         unsigned char *cdb,
78         u32 pr_reg_type)
79 {
80         switch (cdb[0]) {
81         case INQUIRY:
82         case RELEASE:
83         case RELEASE_10:
84                 return 0;
85         default:
86                 return 1;
87         }
88
89         return 1;
90 }
91
92 static int core_scsi2_reservation_check(struct se_cmd *cmd, u32 *pr_reg_type)
93 {
94         struct se_device *dev = cmd->se_dev;
95         struct se_session *sess = cmd->se_sess;
96         int ret;
97
98         if (!sess)
99                 return 0;
100
101         spin_lock(&dev->dev_reservation_lock);
102         if (!dev->dev_reserved_node_acl || !sess) {
103                 spin_unlock(&dev->dev_reservation_lock);
104                 return 0;
105         }
106         if (dev->dev_reserved_node_acl != sess->se_node_acl) {
107                 spin_unlock(&dev->dev_reservation_lock);
108                 return -EINVAL;
109         }
110         if (!(dev->dev_flags & DF_SPC2_RESERVATIONS_WITH_ISID)) {
111                 spin_unlock(&dev->dev_reservation_lock);
112                 return 0;
113         }
114         ret = (dev->dev_res_bin_isid == sess->sess_bin_isid) ? 0 : -EINVAL;
115         spin_unlock(&dev->dev_reservation_lock);
116
117         return ret;
118 }
119
120 static int core_scsi2_reservation_release(struct se_cmd *cmd)
121 {
122         struct se_device *dev = cmd->se_dev;
123         struct se_session *sess = cmd->se_sess;
124         struct se_portal_group *tpg = sess->se_tpg;
125
126         if (!sess || !tpg)
127                 return 0;
128
129         spin_lock(&dev->dev_reservation_lock);
130         if (!dev->dev_reserved_node_acl || !sess) {
131                 spin_unlock(&dev->dev_reservation_lock);
132                 return 0;
133         }
134
135         if (dev->dev_reserved_node_acl != sess->se_node_acl) {
136                 spin_unlock(&dev->dev_reservation_lock);
137                 return 0;
138         }
139         dev->dev_reserved_node_acl = NULL;
140         dev->dev_flags &= ~DF_SPC2_RESERVATIONS;
141         if (dev->dev_flags & DF_SPC2_RESERVATIONS_WITH_ISID) {
142                 dev->dev_res_bin_isid = 0;
143                 dev->dev_flags &= ~DF_SPC2_RESERVATIONS_WITH_ISID;
144         }
145         pr_debug("SCSI-2 Released reservation for %s LUN: %u ->"
146                 " MAPPED LUN: %u for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
147                 cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
148                 sess->se_node_acl->initiatorname);
149         spin_unlock(&dev->dev_reservation_lock);
150
151         return 0;
152 }
153
154 static int core_scsi2_reservation_reserve(struct se_cmd *cmd)
155 {
156         struct se_device *dev = cmd->se_dev;
157         struct se_session *sess = cmd->se_sess;
158         struct se_portal_group *tpg = sess->se_tpg;
159
160         if ((cmd->t_task_cdb[1] & 0x01) &&
161             (cmd->t_task_cdb[1] & 0x02)) {
162                 pr_err("LongIO and Obselete Bits set, returning"
163                                 " ILLEGAL_REQUEST\n");
164                 return PYX_TRANSPORT_ILLEGAL_REQUEST;
165         }
166         /*
167          * This is currently the case for target_core_mod passthrough struct se_cmd
168          * ops
169          */
170         if (!sess || !tpg)
171                 return 0;
172
173         spin_lock(&dev->dev_reservation_lock);
174         if (dev->dev_reserved_node_acl &&
175            (dev->dev_reserved_node_acl != sess->se_node_acl)) {
176                 pr_err("SCSI-2 RESERVATION CONFLIFT for %s fabric\n",
177                         tpg->se_tpg_tfo->get_fabric_name());
178                 pr_err("Original reserver LUN: %u %s\n",
179                         cmd->se_lun->unpacked_lun,
180                         dev->dev_reserved_node_acl->initiatorname);
181                 pr_err("Current attempt - LUN: %u -> MAPPED LUN: %u"
182                         " from %s \n", cmd->se_lun->unpacked_lun,
183                         cmd->se_deve->mapped_lun,
184                         sess->se_node_acl->initiatorname);
185                 spin_unlock(&dev->dev_reservation_lock);
186                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
187         }
188
189         dev->dev_reserved_node_acl = sess->se_node_acl;
190         dev->dev_flags |= DF_SPC2_RESERVATIONS;
191         if (sess->sess_bin_isid != 0) {
192                 dev->dev_res_bin_isid = sess->sess_bin_isid;
193                 dev->dev_flags |= DF_SPC2_RESERVATIONS_WITH_ISID;
194         }
195         pr_debug("SCSI-2 Reserved %s LUN: %u -> MAPPED LUN: %u"
196                 " for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
197                 cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
198                 sess->se_node_acl->initiatorname);
199         spin_unlock(&dev->dev_reservation_lock);
200
201         return 0;
202 }
203
204 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
205                                         struct se_node_acl *, struct se_session *);
206 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
207
208 /*
209  * Setup in target_core_transport.c:transport_generic_cmd_sequencer()
210  * and called via struct se_cmd->transport_emulate_cdb() in TCM processing
211  * thread context.
212  */
213 int core_scsi2_emulate_crh(struct se_cmd *cmd)
214 {
215         struct se_session *se_sess = cmd->se_sess;
216         struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
217         struct t10_pr_registration *pr_reg;
218         struct t10_reservation *pr_tmpl = &su_dev->t10_pr;
219         unsigned char *cdb = &cmd->t_task_cdb[0];
220         int crh = (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS);
221         int conflict = 0;
222
223         if (!se_sess)
224                 return 0;
225
226         if (!crh)
227                 goto after_crh;
228
229         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
230                         se_sess);
231         if (pr_reg) {
232                 /*
233                  * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
234                  * behavior
235                  *
236                  * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
237                  * status, but no reservation shall be established and the
238                  * persistent reservation shall not be changed, if the command
239                  * is received from a) and b) below.
240                  *
241                  * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
242                  * status, but the persistent reservation shall not be released,
243                  * if the command is received from a) and b)
244                  *
245                  * a) An I_T nexus that is a persistent reservation holder; or
246                  * b) An I_T nexus that is registered if a registrants only or
247                  *    all registrants type persistent reservation is present.
248                  *
249                  * In all other cases, a RESERVE(6) command, RESERVE(10) command,
250                  * RELEASE(6) command, or RELEASE(10) command shall be processed
251                  * as defined in SPC-2.
252                  */
253                 if (pr_reg->pr_res_holder) {
254                         core_scsi3_put_pr_reg(pr_reg);
255                         return 0;
256                 }
257                 if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
258                     (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
259                     (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
260                     (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
261                         core_scsi3_put_pr_reg(pr_reg);
262                         return 0;
263                 }
264                 core_scsi3_put_pr_reg(pr_reg);
265                 conflict = 1;
266         } else {
267                 /*
268                  * Following spc2r20 5.5.1 Reservations overview:
269                  *
270                  * If a logical unit has executed a PERSISTENT RESERVE OUT
271                  * command with the REGISTER or the REGISTER AND IGNORE
272                  * EXISTING KEY service action and is still registered by any
273                  * initiator, all RESERVE commands and all RELEASE commands
274                  * regardless of initiator shall conflict and shall terminate
275                  * with a RESERVATION CONFLICT status.
276                  */
277                 spin_lock(&pr_tmpl->registration_lock);
278                 conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
279                 spin_unlock(&pr_tmpl->registration_lock);
280         }
281
282         if (conflict) {
283                 pr_err("Received legacy SPC-2 RESERVE/RELEASE"
284                         " while active SPC-3 registrations exist,"
285                         " returning RESERVATION_CONFLICT\n");
286                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
287         }
288
289 after_crh:
290         if ((cdb[0] == RESERVE) || (cdb[0] == RESERVE_10))
291                 return core_scsi2_reservation_reserve(cmd);
292         else if ((cdb[0] == RELEASE) || (cdb[0] == RELEASE_10))
293                 return core_scsi2_reservation_release(cmd);
294         else
295                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
296 }
297
298 /*
299  * Begin SPC-3/SPC-4 Persistent Reservations emulation support
300  *
301  * This function is called by those initiator ports who are *NOT*
302  * the active PR reservation holder when a reservation is present.
303  */
304 static int core_scsi3_pr_seq_non_holder(
305         struct se_cmd *cmd,
306         unsigned char *cdb,
307         u32 pr_reg_type)
308 {
309         struct se_dev_entry *se_deve;
310         struct se_session *se_sess = cmd->se_sess;
311         int other_cdb = 0, ignore_reg;
312         int registered_nexus = 0, ret = 1; /* Conflict by default */
313         int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
314         int we = 0; /* Write Exclusive */
315         int legacy = 0; /* Act like a legacy device and return
316                          * RESERVATION CONFLICT on some CDBs */
317         /*
318          * A legacy SPC-2 reservation is being held.
319          */
320         if (cmd->se_dev->dev_flags & DF_SPC2_RESERVATIONS)
321                 return core_scsi2_reservation_seq_non_holder(cmd,
322                                         cdb, pr_reg_type);
323
324         se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
325         /*
326          * Determine if the registration should be ignored due to
327          * non-matching ISIDs in core_scsi3_pr_reservation_check().
328          */
329         ignore_reg = (pr_reg_type & 0x80000000);
330         if (ignore_reg)
331                 pr_reg_type &= ~0x80000000;
332
333         switch (pr_reg_type) {
334         case PR_TYPE_WRITE_EXCLUSIVE:
335                 we = 1;
336         case PR_TYPE_EXCLUSIVE_ACCESS:
337                 /*
338                  * Some commands are only allowed for the persistent reservation
339                  * holder.
340                  */
341                 if ((se_deve->def_pr_registered) && !(ignore_reg))
342                         registered_nexus = 1;
343                 break;
344         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
345                 we = 1;
346         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
347                 /*
348                  * Some commands are only allowed for registered I_T Nexuses.
349                  */
350                 reg_only = 1;
351                 if ((se_deve->def_pr_registered) && !(ignore_reg))
352                         registered_nexus = 1;
353                 break;
354         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
355                 we = 1;
356         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
357                 /*
358                  * Each registered I_T Nexus is a reservation holder.
359                  */
360                 all_reg = 1;
361                 if ((se_deve->def_pr_registered) && !(ignore_reg))
362                         registered_nexus = 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 core_scsi2_emulate_crh() */
423                 ret = 0;
424                 break;
425         case RESERVE:
426         case RESERVE_10:
427                 /* Handled by CRH=1 in core_scsi2_emulate_crh() */
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 READ_MEDIA_SERIAL_NUMBER:
472         case REPORT_LUNS:
473         case REQUEST_SENSE:
474                 ret = 0; /*/ Allowed CDBs */
475                 break;
476         default:
477                 other_cdb = 1;
478                 break;
479         }
480         /*
481          * Case where the CDB is explicitly allowed in the above switch
482          * statement.
483          */
484         if (!ret && !other_cdb) {
485 #if 0
486                 pr_debug("Allowing explict CDB: 0x%02x for %s"
487                         " reservation holder\n", cdb[0],
488                         core_scsi3_pr_dump_type(pr_reg_type));
489 #endif
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 #if 0
518                         if (!registered_nexus) {
519                                 pr_debug("Allowing implict 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 #endif
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 #if 0
534                         pr_debug("Allowing implict CDB: 0x%02x for %s"
535                                 " reservation\n", cdb[0],
536                                 core_scsi3_pr_dump_type(pr_reg_type));
537 #endif
538                         return 0;
539                 }
540         }
541         pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
542                 " for %s reservation\n", transport_dump_cmd_direction(cmd),
543                 (registered_nexus) ? "" : "un",
544                 se_sess->se_node_acl->initiatorname, cdb[0],
545                 core_scsi3_pr_dump_type(pr_reg_type));
546
547         return 1; /* Conflict by default */
548 }
549
550 static u32 core_scsi3_pr_generation(struct se_device *dev)
551 {
552         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
553         u32 prg;
554         /*
555          * PRGeneration field shall contain the value of a 32-bit wrapping
556          * counter mainted by the device server.
557          *
558          * Note that this is done regardless of Active Persist across
559          * Target PowerLoss (APTPL)
560          *
561          * See spc4r17 section 6.3.12 READ_KEYS service action
562          */
563         spin_lock(&dev->dev_reservation_lock);
564         prg = su_dev->t10_pr.pr_generation++;
565         spin_unlock(&dev->dev_reservation_lock);
566
567         return prg;
568 }
569
570 static int core_scsi3_pr_reservation_check(
571         struct se_cmd *cmd,
572         u32 *pr_reg_type)
573 {
574         struct se_device *dev = cmd->se_dev;
575         struct se_session *sess = cmd->se_sess;
576         int ret;
577
578         if (!sess)
579                 return 0;
580         /*
581          * A legacy SPC-2 reservation is being held.
582          */
583         if (dev->dev_flags & DF_SPC2_RESERVATIONS)
584                 return core_scsi2_reservation_check(cmd, pr_reg_type);
585
586         spin_lock(&dev->dev_reservation_lock);
587         if (!dev->dev_pr_res_holder) {
588                 spin_unlock(&dev->dev_reservation_lock);
589                 return 0;
590         }
591         *pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
592         cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
593         if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl) {
594                 spin_unlock(&dev->dev_reservation_lock);
595                 return -EINVAL;
596         }
597         if (!dev->dev_pr_res_holder->isid_present_at_reg) {
598                 spin_unlock(&dev->dev_reservation_lock);
599                 return 0;
600         }
601         ret = (dev->dev_pr_res_holder->pr_reg_bin_isid ==
602                sess->sess_bin_isid) ? 0 : -EINVAL;
603         /*
604          * Use bit in *pr_reg_type to notify ISID mismatch in
605          * core_scsi3_pr_seq_non_holder().
606          */
607         if (ret != 0)
608                 *pr_reg_type |= 0x80000000;
609         spin_unlock(&dev->dev_reservation_lock);
610
611         return ret;
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_dev_entry *deve,
618         unsigned char *isid,
619         u64 sa_res_key,
620         int all_tg_pt,
621         int aptpl)
622 {
623         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
624         struct t10_pr_registration *pr_reg;
625
626         pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_ATOMIC);
627         if (!pr_reg) {
628                 pr_err("Unable to allocate struct t10_pr_registration\n");
629                 return NULL;
630         }
631
632         pr_reg->pr_aptpl_buf = kzalloc(su_dev->t10_pr.pr_aptpl_buf_len,
633                                         GFP_ATOMIC);
634         if (!pr_reg->pr_aptpl_buf) {
635                 pr_err("Unable to allocate pr_reg->pr_aptpl_buf\n");
636                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
637                 return NULL;
638         }
639
640         INIT_LIST_HEAD(&pr_reg->pr_reg_list);
641         INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
642         INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
643         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
644         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
645         atomic_set(&pr_reg->pr_res_holders, 0);
646         pr_reg->pr_reg_nacl = nacl;
647         pr_reg->pr_reg_deve = deve;
648         pr_reg->pr_res_mapped_lun = deve->mapped_lun;
649         pr_reg->pr_aptpl_target_lun = deve->se_lun->unpacked_lun;
650         pr_reg->pr_res_key = sa_res_key;
651         pr_reg->pr_reg_all_tg_pt = all_tg_pt;
652         pr_reg->pr_reg_aptpl = aptpl;
653         pr_reg->pr_reg_tg_pt_lun = deve->se_lun;
654         /*
655          * If an ISID value for this SCSI Initiator Port exists,
656          * save it to the registration now.
657          */
658         if (isid != NULL) {
659                 pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
660                 snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
661                 pr_reg->isid_present_at_reg = 1;
662         }
663
664         return pr_reg;
665 }
666
667 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
668 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
669
670 /*
671  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
672  * modes.
673  */
674 static struct t10_pr_registration *__core_scsi3_alloc_registration(
675         struct se_device *dev,
676         struct se_node_acl *nacl,
677         struct se_dev_entry *deve,
678         unsigned char *isid,
679         u64 sa_res_key,
680         int all_tg_pt,
681         int aptpl)
682 {
683         struct se_dev_entry *deve_tmp;
684         struct se_node_acl *nacl_tmp;
685         struct se_port *port, *port_tmp;
686         struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
687         struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
688         int ret;
689         /*
690          * Create a registration for the I_T Nexus upon which the
691          * PROUT REGISTER was received.
692          */
693         pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, deve, isid,
694                         sa_res_key, all_tg_pt, aptpl);
695         if (!pr_reg)
696                 return NULL;
697         /*
698          * Return pointer to pr_reg for ALL_TG_PT=0
699          */
700         if (!all_tg_pt)
701                 return pr_reg;
702         /*
703          * Create list of matching SCSI Initiator Port registrations
704          * for ALL_TG_PT=1
705          */
706         spin_lock(&dev->se_port_lock);
707         list_for_each_entry_safe(port, port_tmp, &dev->dev_sep_list, sep_list) {
708                 atomic_inc(&port->sep_tg_pt_ref_cnt);
709                 smp_mb__after_atomic_inc();
710                 spin_unlock(&dev->se_port_lock);
711
712                 spin_lock_bh(&port->sep_alua_lock);
713                 list_for_each_entry(deve_tmp, &port->sep_alua_list,
714                                         alua_port_list) {
715                         /*
716                          * This pointer will be NULL for demo mode MappedLUNs
717                          * that have not been make explict via a ConfigFS
718                          * MappedLUN group for the SCSI Initiator Node ACL.
719                          */
720                         if (!deve_tmp->se_lun_acl)
721                                 continue;
722
723                         nacl_tmp = deve_tmp->se_lun_acl->se_lun_nacl;
724                         /*
725                          * Skip the matching struct se_node_acl that is allocated
726                          * above..
727                          */
728                         if (nacl == nacl_tmp)
729                                 continue;
730                         /*
731                          * Only perform PR registrations for target ports on
732                          * the same fabric module as the REGISTER w/ ALL_TG_PT=1
733                          * arrived.
734                          */
735                         if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
736                                 continue;
737                         /*
738                          * Look for a matching Initiator Node ACL in ASCII format
739                          */
740                         if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
741                                 continue;
742
743                         atomic_inc(&deve_tmp->pr_ref_count);
744                         smp_mb__after_atomic_inc();
745                         spin_unlock_bh(&port->sep_alua_lock);
746                         /*
747                          * Grab a configfs group dependency that is released
748                          * for the exception path at label out: below, or upon
749                          * completion of adding ALL_TG_PT=1 registrations in
750                          * __core_scsi3_add_registration()
751                          */
752                         ret = core_scsi3_lunacl_depend_item(deve_tmp);
753                         if (ret < 0) {
754                                 pr_err("core_scsi3_lunacl_depend"
755                                                 "_item() failed\n");
756                                 atomic_dec(&port->sep_tg_pt_ref_cnt);
757                                 smp_mb__after_atomic_dec();
758                                 atomic_dec(&deve_tmp->pr_ref_count);
759                                 smp_mb__after_atomic_dec();
760                                 goto out;
761                         }
762                         /*
763                          * Located a matching SCSI Initiator Port on a different
764                          * port, allocate the pr_reg_atp and attach it to the
765                          * pr_reg->pr_reg_atp_list that will be processed once
766                          * the original *pr_reg is processed in
767                          * __core_scsi3_add_registration()
768                          */
769                         pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
770                                                 nacl_tmp, deve_tmp, NULL,
771                                                 sa_res_key, all_tg_pt, aptpl);
772                         if (!pr_reg_atp) {
773                                 atomic_dec(&port->sep_tg_pt_ref_cnt);
774                                 smp_mb__after_atomic_dec();
775                                 atomic_dec(&deve_tmp->pr_ref_count);
776                                 smp_mb__after_atomic_dec();
777                                 core_scsi3_lunacl_undepend_item(deve_tmp);
778                                 goto out;
779                         }
780
781                         list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
782                                       &pr_reg->pr_reg_atp_list);
783                         spin_lock_bh(&port->sep_alua_lock);
784                 }
785                 spin_unlock_bh(&port->sep_alua_lock);
786
787                 spin_lock(&dev->se_port_lock);
788                 atomic_dec(&port->sep_tg_pt_ref_cnt);
789                 smp_mb__after_atomic_dec();
790         }
791         spin_unlock(&dev->se_port_lock);
792
793         return pr_reg;
794 out:
795         list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
796                         &pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
797                 list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
798                 core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
799                 kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
800         }
801         kmem_cache_free(t10_pr_reg_cache, pr_reg);
802         return NULL;
803 }
804
805 int core_scsi3_alloc_aptpl_registration(
806         struct t10_reservation *pr_tmpl,
807         u64 sa_res_key,
808         unsigned char *i_port,
809         unsigned char *isid,
810         u32 mapped_lun,
811         unsigned char *t_port,
812         u16 tpgt,
813         u32 target_lun,
814         int res_holder,
815         int all_tg_pt,
816         u8 type)
817 {
818         struct t10_pr_registration *pr_reg;
819
820         if (!i_port || !t_port || !sa_res_key) {
821                 pr_err("Illegal parameters for APTPL registration\n");
822                 return -EINVAL;
823         }
824
825         pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
826         if (!pr_reg) {
827                 pr_err("Unable to allocate struct t10_pr_registration\n");
828                 return -ENOMEM;
829         }
830         pr_reg->pr_aptpl_buf = kzalloc(pr_tmpl->pr_aptpl_buf_len, GFP_KERNEL);
831
832         INIT_LIST_HEAD(&pr_reg->pr_reg_list);
833         INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
834         INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
835         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
836         INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
837         atomic_set(&pr_reg->pr_res_holders, 0);
838         pr_reg->pr_reg_nacl = NULL;
839         pr_reg->pr_reg_deve = NULL;
840         pr_reg->pr_res_mapped_lun = mapped_lun;
841         pr_reg->pr_aptpl_target_lun = target_lun;
842         pr_reg->pr_res_key = sa_res_key;
843         pr_reg->pr_reg_all_tg_pt = all_tg_pt;
844         pr_reg->pr_reg_aptpl = 1;
845         pr_reg->pr_reg_tg_pt_lun = NULL;
846         pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
847         pr_reg->pr_res_type = type;
848         /*
849          * If an ISID value had been saved in APTPL metadata for this
850          * SCSI Initiator Port, restore it now.
851          */
852         if (isid != NULL) {
853                 pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
854                 snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
855                 pr_reg->isid_present_at_reg = 1;
856         }
857         /*
858          * Copy the i_port and t_port information from caller.
859          */
860         snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
861         snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
862         pr_reg->pr_reg_tpgt = tpgt;
863         /*
864          * Set pr_res_holder from caller, the pr_reg who is the reservation
865          * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
866          * the Initiator Node LUN ACL from the fabric module is created for
867          * this registration.
868          */
869         pr_reg->pr_res_holder = res_holder;
870
871         list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
872         pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
873                         " metadata\n", (res_holder) ? "+reservation" : "");
874         return 0;
875 }
876
877 static void core_scsi3_aptpl_reserve(
878         struct se_device *dev,
879         struct se_portal_group *tpg,
880         struct se_node_acl *node_acl,
881         struct t10_pr_registration *pr_reg)
882 {
883         char i_buf[PR_REG_ISID_ID_LEN];
884         int prf_isid;
885
886         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
887         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
888                                 PR_REG_ISID_ID_LEN);
889
890         spin_lock(&dev->dev_reservation_lock);
891         dev->dev_pr_res_holder = pr_reg;
892         spin_unlock(&dev->dev_reservation_lock);
893
894         pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
895                 " new reservation holder TYPE: %s ALL_TG_PT: %d\n",
896                 tpg->se_tpg_tfo->get_fabric_name(),
897                 core_scsi3_pr_dump_type(pr_reg->pr_res_type),
898                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
899         pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
900                 tpg->se_tpg_tfo->get_fabric_name(), node_acl->initiatorname,
901                 (prf_isid) ? &i_buf[0] : "");
902 }
903
904 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
905                                 struct t10_pr_registration *, int, int);
906
907 static int __core_scsi3_check_aptpl_registration(
908         struct se_device *dev,
909         struct se_portal_group *tpg,
910         struct se_lun *lun,
911         u32 target_lun,
912         struct se_node_acl *nacl,
913         struct se_dev_entry *deve)
914 {
915         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
916         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
917         unsigned char i_port[PR_APTPL_MAX_IPORT_LEN];
918         unsigned char t_port[PR_APTPL_MAX_TPORT_LEN];
919         u16 tpgt;
920
921         memset(i_port, 0, PR_APTPL_MAX_IPORT_LEN);
922         memset(t_port, 0, PR_APTPL_MAX_TPORT_LEN);
923         /*
924          * Copy Initiator Port information from struct se_node_acl
925          */
926         snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
927         snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
928                         tpg->se_tpg_tfo->tpg_get_wwn(tpg));
929         tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
930         /*
931          * Look for the matching registrations+reservation from those
932          * created from APTPL metadata.  Note that multiple registrations
933          * may exist for fabrics that use ISIDs in their SCSI Initiator Port
934          * TransportIDs.
935          */
936         spin_lock(&pr_tmpl->aptpl_reg_lock);
937         list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
938                                 pr_reg_aptpl_list) {
939                 if (!strcmp(pr_reg->pr_iport, i_port) &&
940                      (pr_reg->pr_res_mapped_lun == deve->mapped_lun) &&
941                     !(strcmp(pr_reg->pr_tport, t_port)) &&
942                      (pr_reg->pr_reg_tpgt == tpgt) &&
943                      (pr_reg->pr_aptpl_target_lun == target_lun)) {
944
945                         pr_reg->pr_reg_nacl = nacl;
946                         pr_reg->pr_reg_deve = deve;
947                         pr_reg->pr_reg_tg_pt_lun = lun;
948
949                         list_del(&pr_reg->pr_reg_aptpl_list);
950                         spin_unlock(&pr_tmpl->aptpl_reg_lock);
951                         /*
952                          * At this point all of the pointers in *pr_reg will
953                          * be setup, so go ahead and add the registration.
954                          */
955
956                         __core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
957                         /*
958                          * If this registration is the reservation holder,
959                          * make that happen now..
960                          */
961                         if (pr_reg->pr_res_holder)
962                                 core_scsi3_aptpl_reserve(dev, tpg,
963                                                 nacl, pr_reg);
964                         /*
965                          * Reenable pr_aptpl_active to accept new metadata
966                          * updates once the SCSI device is active again..
967                          */
968                         spin_lock(&pr_tmpl->aptpl_reg_lock);
969                         pr_tmpl->pr_aptpl_active = 1;
970                 }
971         }
972         spin_unlock(&pr_tmpl->aptpl_reg_lock);
973
974         return 0;
975 }
976
977 int core_scsi3_check_aptpl_registration(
978         struct se_device *dev,
979         struct se_portal_group *tpg,
980         struct se_lun *lun,
981         struct se_lun_acl *lun_acl)
982 {
983         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
984         struct se_node_acl *nacl = lun_acl->se_lun_nacl;
985         struct se_dev_entry *deve = &nacl->device_list[lun_acl->mapped_lun];
986
987         if (su_dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
988                 return 0;
989
990         return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
991                                 lun->unpacked_lun, nacl, deve);
992 }
993
994 static void __core_scsi3_dump_registration(
995         struct target_core_fabric_ops *tfo,
996         struct se_device *dev,
997         struct se_node_acl *nacl,
998         struct t10_pr_registration *pr_reg,
999         int register_type)
1000 {
1001         struct se_portal_group *se_tpg = nacl->se_tpg;
1002         char i_buf[PR_REG_ISID_ID_LEN];
1003         int prf_isid;
1004
1005         memset(&i_buf[0], 0, PR_REG_ISID_ID_LEN);
1006         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
1007                                 PR_REG_ISID_ID_LEN);
1008
1009         pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
1010                 " Node: %s%s\n", tfo->get_fabric_name(), (register_type == 2) ?
1011                 "_AND_MOVE" : (register_type == 1) ?
1012                 "_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
1013                 (prf_isid) ? i_buf : "");
1014         pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
1015                  tfo->get_fabric_name(), tfo->tpg_get_wwn(se_tpg),
1016                 tfo->tpg_get_tag(se_tpg));
1017         pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1018                 " Port(s)\n",  tfo->get_fabric_name(),
1019                 (pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1020                 dev->transport->name);
1021         pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1022                 " 0x%08x  APTPL: %d\n", tfo->get_fabric_name(),
1023                 pr_reg->pr_res_key, pr_reg->pr_res_generation,
1024                 pr_reg->pr_reg_aptpl);
1025 }
1026
1027 /*
1028  * this function can be called with struct se_device->dev_reservation_lock
1029  * when register_move = 1
1030  */
1031 static void __core_scsi3_add_registration(
1032         struct se_device *dev,
1033         struct se_node_acl *nacl,
1034         struct t10_pr_registration *pr_reg,
1035         int register_type,
1036         int register_move)
1037 {
1038         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1039         struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1040         struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1041         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1042
1043         /*
1044          * Increment PRgeneration counter for struct se_device upon a successful
1045          * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1046          *
1047          * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1048          * action, the struct se_device->dev_reservation_lock will already be held,
1049          * so we do not call core_scsi3_pr_generation() which grabs the lock
1050          * for the REGISTER.
1051          */
1052         pr_reg->pr_res_generation = (register_move) ?
1053                         su_dev->t10_pr.pr_generation++ :
1054                         core_scsi3_pr_generation(dev);
1055
1056         spin_lock(&pr_tmpl->registration_lock);
1057         list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1058         pr_reg->pr_reg_deve->def_pr_registered = 1;
1059
1060         __core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1061         spin_unlock(&pr_tmpl->registration_lock);
1062         /*
1063          * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1064          */
1065         if (!pr_reg->pr_reg_all_tg_pt || register_move)
1066                 return;
1067         /*
1068          * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1069          * allocated in __core_scsi3_alloc_registration()
1070          */
1071         list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1072                         &pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1073                 list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1074
1075                 pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1076
1077                 spin_lock(&pr_tmpl->registration_lock);
1078                 list_add_tail(&pr_reg_tmp->pr_reg_list,
1079                               &pr_tmpl->registration_list);
1080                 pr_reg_tmp->pr_reg_deve->def_pr_registered = 1;
1081
1082                 __core_scsi3_dump_registration(tfo, dev,
1083                                 pr_reg_tmp->pr_reg_nacl, pr_reg_tmp,
1084                                 register_type);
1085                 spin_unlock(&pr_tmpl->registration_lock);
1086                 /*
1087                  * Drop configfs group dependency reference from
1088                  * __core_scsi3_alloc_registration()
1089                  */
1090                 core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1091         }
1092 }
1093
1094 static int core_scsi3_alloc_registration(
1095         struct se_device *dev,
1096         struct se_node_acl *nacl,
1097         struct se_dev_entry *deve,
1098         unsigned char *isid,
1099         u64 sa_res_key,
1100         int all_tg_pt,
1101         int aptpl,
1102         int register_type,
1103         int register_move)
1104 {
1105         struct t10_pr_registration *pr_reg;
1106
1107         pr_reg = __core_scsi3_alloc_registration(dev, nacl, deve, isid,
1108                         sa_res_key, all_tg_pt, aptpl);
1109         if (!pr_reg)
1110                 return -EPERM;
1111
1112         __core_scsi3_add_registration(dev, nacl, pr_reg,
1113                         register_type, register_move);
1114         return 0;
1115 }
1116
1117 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1118         struct se_device *dev,
1119         struct se_node_acl *nacl,
1120         unsigned char *isid)
1121 {
1122         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1123         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1124         struct se_portal_group *tpg;
1125
1126         spin_lock(&pr_tmpl->registration_lock);
1127         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1128                         &pr_tmpl->registration_list, pr_reg_list) {
1129                 /*
1130                  * First look for a matching struct se_node_acl
1131                  */
1132                 if (pr_reg->pr_reg_nacl != nacl)
1133                         continue;
1134
1135                 tpg = pr_reg->pr_reg_nacl->se_tpg;
1136                 /*
1137                  * If this registration does NOT contain a fabric provided
1138                  * ISID, then we have found a match.
1139                  */
1140                 if (!pr_reg->isid_present_at_reg) {
1141                         /*
1142                          * Determine if this SCSI device server requires that
1143                          * SCSI Intiatior TransportID w/ ISIDs is enforced
1144                          * for fabric modules (iSCSI) requiring them.
1145                          */
1146                         if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1147                                 if (dev->se_sub_dev->se_dev_attrib.enforce_pr_isids)
1148                                         continue;
1149                         }
1150                         atomic_inc(&pr_reg->pr_res_holders);
1151                         smp_mb__after_atomic_inc();
1152                         spin_unlock(&pr_tmpl->registration_lock);
1153                         return pr_reg;
1154                 }
1155                 /*
1156                  * If the *pr_reg contains a fabric defined ISID for multi-value
1157                  * SCSI Initiator Port TransportIDs, then we expect a valid
1158                  * matching ISID to be provided by the local SCSI Initiator Port.
1159                  */
1160                 if (!isid)
1161                         continue;
1162                 if (strcmp(isid, pr_reg->pr_reg_isid))
1163                         continue;
1164
1165                 atomic_inc(&pr_reg->pr_res_holders);
1166                 smp_mb__after_atomic_inc();
1167                 spin_unlock(&pr_tmpl->registration_lock);
1168                 return pr_reg;
1169         }
1170         spin_unlock(&pr_tmpl->registration_lock);
1171
1172         return NULL;
1173 }
1174
1175 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1176         struct se_device *dev,
1177         struct se_node_acl *nacl,
1178         struct se_session *sess)
1179 {
1180         struct se_portal_group *tpg = nacl->se_tpg;
1181         unsigned char buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
1182
1183         if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1184                 memset(&buf[0], 0, PR_REG_ISID_LEN);
1185                 tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1186                                         PR_REG_ISID_LEN);
1187                 isid_ptr = &buf[0];
1188         }
1189
1190         return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1191 }
1192
1193 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1194 {
1195         atomic_dec(&pr_reg->pr_res_holders);
1196         smp_mb__after_atomic_dec();
1197 }
1198
1199 static int core_scsi3_check_implict_release(
1200         struct se_device *dev,
1201         struct t10_pr_registration *pr_reg)
1202 {
1203         struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1204         struct t10_pr_registration *pr_res_holder;
1205         int ret = 0;
1206
1207         spin_lock(&dev->dev_reservation_lock);
1208         pr_res_holder = dev->dev_pr_res_holder;
1209         if (!pr_res_holder) {
1210                 spin_unlock(&dev->dev_reservation_lock);
1211                 return ret;
1212         }
1213         if (pr_res_holder == pr_reg) {
1214                 /*
1215                  * Perform an implict RELEASE if the registration that
1216                  * is being released is holding the reservation.
1217                  *
1218                  * From spc4r17, section 5.7.11.1:
1219                  *
1220                  * e) If the I_T nexus is the persistent reservation holder
1221                  *    and the persistent reservation is not an all registrants
1222                  *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1223                  *    service action or REGISTER AND  IGNORE EXISTING KEY
1224                  *    service action with the SERVICE ACTION RESERVATION KEY
1225                  *    field set to zero (see 5.7.11.3).
1226                  */
1227                 __core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0);
1228                 ret = 1;
1229                 /*
1230                  * For 'All Registrants' reservation types, all existing
1231                  * registrations are still processed as reservation holders
1232                  * in core_scsi3_pr_seq_non_holder() after the initial
1233                  * reservation holder is implictly released here.
1234                  */
1235         } else if (pr_reg->pr_reg_all_tg_pt &&
1236                   (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1237                           pr_reg->pr_reg_nacl->initiatorname)) &&
1238                   (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1239                 pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1240                         " UNREGISTER while existing reservation with matching"
1241                         " key 0x%016Lx is present from another SCSI Initiator"
1242                         " Port\n", pr_reg->pr_res_key);
1243                 ret = -EPERM;
1244         }
1245         spin_unlock(&dev->dev_reservation_lock);
1246
1247         return ret;
1248 }
1249
1250 /*
1251  * Called with struct t10_reservation->registration_lock held.
1252  */
1253 static void __core_scsi3_free_registration(
1254         struct se_device *dev,
1255         struct t10_pr_registration *pr_reg,
1256         struct list_head *preempt_and_abort_list,
1257         int dec_holders)
1258 {
1259         struct target_core_fabric_ops *tfo =
1260                         pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1261         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1262         char i_buf[PR_REG_ISID_ID_LEN];
1263         int prf_isid;
1264
1265         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1266         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
1267                                 PR_REG_ISID_ID_LEN);
1268
1269         pr_reg->pr_reg_deve->def_pr_registered = 0;
1270         pr_reg->pr_reg_deve->pr_res_key = 0;
1271         list_del(&pr_reg->pr_reg_list);
1272         /*
1273          * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1274          * so call core_scsi3_put_pr_reg() to decrement our reference.
1275          */
1276         if (dec_holders)
1277                 core_scsi3_put_pr_reg(pr_reg);
1278         /*
1279          * Wait until all reference from any other I_T nexuses for this
1280          * *pr_reg have been released.  Because list_del() is called above,
1281          * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1282          * count back to zero, and we release *pr_reg.
1283          */
1284         while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1285                 spin_unlock(&pr_tmpl->registration_lock);
1286                 pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1287                                 tfo->get_fabric_name());
1288                 cpu_relax();
1289                 spin_lock(&pr_tmpl->registration_lock);
1290         }
1291
1292         pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1293                 " Node: %s%s\n", tfo->get_fabric_name(),
1294                 pr_reg->pr_reg_nacl->initiatorname,
1295                 (prf_isid) ? &i_buf[0] : "");
1296         pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1297                 " Port(s)\n", tfo->get_fabric_name(),
1298                 (pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1299                 dev->transport->name);
1300         pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1301                 " 0x%08x\n", tfo->get_fabric_name(), pr_reg->pr_res_key,
1302                 pr_reg->pr_res_generation);
1303
1304         if (!preempt_and_abort_list) {
1305                 pr_reg->pr_reg_deve = NULL;
1306                 pr_reg->pr_reg_nacl = NULL;
1307                 kfree(pr_reg->pr_aptpl_buf);
1308                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
1309                 return;
1310         }
1311         /*
1312          * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1313          * are released once the ABORT_TASK_SET has completed..
1314          */
1315         list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1316 }
1317
1318 void core_scsi3_free_pr_reg_from_nacl(
1319         struct se_device *dev,
1320         struct se_node_acl *nacl)
1321 {
1322         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1323         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1324         /*
1325          * If the passed se_node_acl matches the reservation holder,
1326          * release the reservation.
1327          */
1328         spin_lock(&dev->dev_reservation_lock);
1329         pr_res_holder = dev->dev_pr_res_holder;
1330         if ((pr_res_holder != NULL) &&
1331             (pr_res_holder->pr_reg_nacl == nacl))
1332                 __core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0);
1333         spin_unlock(&dev->dev_reservation_lock);
1334         /*
1335          * Release any registration associated with the struct se_node_acl.
1336          */
1337         spin_lock(&pr_tmpl->registration_lock);
1338         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1339                         &pr_tmpl->registration_list, pr_reg_list) {
1340
1341                 if (pr_reg->pr_reg_nacl != nacl)
1342                         continue;
1343
1344                 __core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1345         }
1346         spin_unlock(&pr_tmpl->registration_lock);
1347 }
1348
1349 void core_scsi3_free_all_registrations(
1350         struct se_device *dev)
1351 {
1352         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1353         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1354
1355         spin_lock(&dev->dev_reservation_lock);
1356         pr_res_holder = dev->dev_pr_res_holder;
1357         if (pr_res_holder != NULL) {
1358                 struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1359                 __core_scsi3_complete_pro_release(dev, pr_res_nacl,
1360                                 pr_res_holder, 0);
1361         }
1362         spin_unlock(&dev->dev_reservation_lock);
1363
1364         spin_lock(&pr_tmpl->registration_lock);
1365         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1366                         &pr_tmpl->registration_list, pr_reg_list) {
1367
1368                 __core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1369         }
1370         spin_unlock(&pr_tmpl->registration_lock);
1371
1372         spin_lock(&pr_tmpl->aptpl_reg_lock);
1373         list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1374                                 pr_reg_aptpl_list) {
1375                 list_del(&pr_reg->pr_reg_aptpl_list);
1376                 kfree(pr_reg->pr_aptpl_buf);
1377                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
1378         }
1379         spin_unlock(&pr_tmpl->aptpl_reg_lock);
1380 }
1381
1382 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1383 {
1384         return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1385                         &tpg->tpg_group.cg_item);
1386 }
1387
1388 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1389 {
1390         configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1391                         &tpg->tpg_group.cg_item);
1392
1393         atomic_dec(&tpg->tpg_pr_ref_count);
1394         smp_mb__after_atomic_dec();
1395 }
1396
1397 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1398 {
1399         struct se_portal_group *tpg = nacl->se_tpg;
1400
1401         if (nacl->dynamic_node_acl)
1402                 return 0;
1403
1404         return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1405                         &nacl->acl_group.cg_item);
1406 }
1407
1408 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1409 {
1410         struct se_portal_group *tpg = nacl->se_tpg;
1411
1412         if (nacl->dynamic_node_acl) {
1413                 atomic_dec(&nacl->acl_pr_ref_count);
1414                 smp_mb__after_atomic_dec();
1415                 return;
1416         }
1417
1418         configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1419                         &nacl->acl_group.cg_item);
1420
1421         atomic_dec(&nacl->acl_pr_ref_count);
1422         smp_mb__after_atomic_dec();
1423 }
1424
1425 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1426 {
1427         struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1428         struct se_node_acl *nacl;
1429         struct se_portal_group *tpg;
1430         /*
1431          * For nacl->dynamic_node_acl=1
1432          */
1433         if (!lun_acl)
1434                 return 0;
1435
1436         nacl = lun_acl->se_lun_nacl;
1437         tpg = nacl->se_tpg;
1438
1439         return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1440                         &lun_acl->se_lun_group.cg_item);
1441 }
1442
1443 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1444 {
1445         struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1446         struct se_node_acl *nacl;
1447         struct se_portal_group *tpg;
1448         /*
1449          * For nacl->dynamic_node_acl=1
1450          */
1451         if (!lun_acl) {
1452                 atomic_dec(&se_deve->pr_ref_count);
1453                 smp_mb__after_atomic_dec();
1454                 return;
1455         }
1456         nacl = lun_acl->se_lun_nacl;
1457         tpg = nacl->se_tpg;
1458
1459         configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1460                         &lun_acl->se_lun_group.cg_item);
1461
1462         atomic_dec(&se_deve->pr_ref_count);
1463         smp_mb__after_atomic_dec();
1464 }
1465
1466 static int core_scsi3_decode_spec_i_port(
1467         struct se_cmd *cmd,
1468         struct se_portal_group *tpg,
1469         unsigned char *l_isid,
1470         u64 sa_res_key,
1471         int all_tg_pt,
1472         int aptpl)
1473 {
1474         struct se_device *dev = cmd->se_dev;
1475         struct se_port *tmp_port;
1476         struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1477         struct se_session *se_sess = cmd->se_sess;
1478         struct se_node_acl *dest_node_acl = NULL;
1479         struct se_dev_entry *dest_se_deve = NULL, *local_se_deve;
1480         struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1481         struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1482         struct list_head tid_dest_list;
1483         struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1484         struct target_core_fabric_ops *tmp_tf_ops;
1485         unsigned char *buf;
1486         unsigned char *ptr, *i_str = NULL, proto_ident, tmp_proto_ident;
1487         char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
1488         u32 tpdl, tid_len = 0;
1489         int ret, dest_local_nexus, prf_isid;
1490         u32 dest_rtpi = 0;
1491
1492         memset(dest_iport, 0, 64);
1493         INIT_LIST_HEAD(&tid_dest_list);
1494
1495         local_se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
1496         /*
1497          * Allocate a struct pr_transport_id_holder and setup the
1498          * local_node_acl and local_se_deve pointers and add to
1499          * struct list_head tid_dest_list for add registration
1500          * processing in the loop of tid_dest_list below.
1501          */
1502         tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1503         if (!tidh_new) {
1504                 pr_err("Unable to allocate tidh_new\n");
1505                 return PYX_TRANSPORT_LU_COMM_FAILURE;
1506         }
1507         INIT_LIST_HEAD(&tidh_new->dest_list);
1508         tidh_new->dest_tpg = tpg;
1509         tidh_new->dest_node_acl = se_sess->se_node_acl;
1510         tidh_new->dest_se_deve = local_se_deve;
1511
1512         local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1513                                 se_sess->se_node_acl, local_se_deve, l_isid,
1514                                 sa_res_key, all_tg_pt, aptpl);
1515         if (!local_pr_reg) {
1516                 kfree(tidh_new);
1517                 return PYX_TRANSPORT_LU_COMM_FAILURE;
1518         }
1519         tidh_new->dest_pr_reg = local_pr_reg;
1520         /*
1521          * The local I_T nexus does not hold any configfs dependances,
1522          * so we set tid_h->dest_local_nexus=1 to prevent the
1523          * configfs_undepend_item() calls in the tid_dest_list loops below.
1524          */
1525         tidh_new->dest_local_nexus = 1;
1526         list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1527
1528         buf = transport_kmap_first_data_page(cmd);
1529         /*
1530          * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1531          * first extract TransportID Parameter Data Length, and make sure
1532          * the value matches up to the SCSI expected data transfer length.
1533          */
1534         tpdl = (buf[24] & 0xff) << 24;
1535         tpdl |= (buf[25] & 0xff) << 16;
1536         tpdl |= (buf[26] & 0xff) << 8;
1537         tpdl |= buf[27] & 0xff;
1538
1539         if ((tpdl + 28) != cmd->data_length) {
1540                 pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1541                         " does not equal CDB data_length: %u\n", tpdl,
1542                         cmd->data_length);
1543                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
1544                 goto out;
1545         }
1546         /*
1547          * Start processing the received transport IDs using the
1548          * receiving I_T Nexus portal's fabric dependent methods to
1549          * obtain the SCSI Initiator Port/Device Identifiers.
1550          */
1551         ptr = &buf[28];
1552
1553         while (tpdl > 0) {
1554                 proto_ident = (ptr[0] & 0x0f);
1555                 dest_tpg = NULL;
1556
1557                 spin_lock(&dev->se_port_lock);
1558                 list_for_each_entry(tmp_port, &dev->dev_sep_list, sep_list) {
1559                         tmp_tpg = tmp_port->sep_tpg;
1560                         if (!tmp_tpg)
1561                                 continue;
1562                         tmp_tf_ops = tmp_tpg->se_tpg_tfo;
1563                         if (!tmp_tf_ops)
1564                                 continue;
1565                         if (!tmp_tf_ops->get_fabric_proto_ident ||
1566                             !tmp_tf_ops->tpg_parse_pr_out_transport_id)
1567                                 continue;
1568                         /*
1569                          * Look for the matching proto_ident provided by
1570                          * the received TransportID
1571                          */
1572                         tmp_proto_ident = tmp_tf_ops->get_fabric_proto_ident(tmp_tpg);
1573                         if (tmp_proto_ident != proto_ident)
1574                                 continue;
1575                         dest_rtpi = tmp_port->sep_rtpi;
1576
1577                         i_str = tmp_tf_ops->tpg_parse_pr_out_transport_id(
1578                                         tmp_tpg, (const char *)ptr, &tid_len,
1579                                         &iport_ptr);
1580                         if (!i_str)
1581                                 continue;
1582
1583                         atomic_inc(&tmp_tpg->tpg_pr_ref_count);
1584                         smp_mb__after_atomic_inc();
1585                         spin_unlock(&dev->se_port_lock);
1586
1587                         ret = core_scsi3_tpg_depend_item(tmp_tpg);
1588                         if (ret != 0) {
1589                                 pr_err(" core_scsi3_tpg_depend_item()"
1590                                         " for tmp_tpg\n");
1591                                 atomic_dec(&tmp_tpg->tpg_pr_ref_count);
1592                                 smp_mb__after_atomic_dec();
1593                                 ret = PYX_TRANSPORT_LU_COMM_FAILURE;
1594                                 goto out;
1595                         }
1596                         /*
1597                          * Locate the desination initiator ACL to be registered
1598                          * from the decoded fabric module specific TransportID
1599                          * at *i_str.
1600                          */
1601                         spin_lock_bh(&tmp_tpg->acl_node_lock);
1602                         dest_node_acl = __core_tpg_get_initiator_node_acl(
1603                                                 tmp_tpg, i_str);
1604                         if (dest_node_acl) {
1605                                 atomic_inc(&dest_node_acl->acl_pr_ref_count);
1606                                 smp_mb__after_atomic_inc();
1607                         }
1608                         spin_unlock_bh(&tmp_tpg->acl_node_lock);
1609
1610                         if (!dest_node_acl) {
1611                                 core_scsi3_tpg_undepend_item(tmp_tpg);
1612                                 spin_lock(&dev->se_port_lock);
1613                                 continue;
1614                         }
1615
1616                         ret = core_scsi3_nodeacl_depend_item(dest_node_acl);
1617                         if (ret != 0) {
1618                                 pr_err("configfs_depend_item() failed"
1619                                         " for dest_node_acl->acl_group\n");
1620                                 atomic_dec(&dest_node_acl->acl_pr_ref_count);
1621                                 smp_mb__after_atomic_dec();
1622                                 core_scsi3_tpg_undepend_item(tmp_tpg);
1623                                 ret = PYX_TRANSPORT_LU_COMM_FAILURE;
1624                                 goto out;
1625                         }
1626
1627                         dest_tpg = tmp_tpg;
1628                         pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1629                                 " %s Port RTPI: %hu\n",
1630                                 dest_tpg->se_tpg_tfo->get_fabric_name(),
1631                                 dest_node_acl->initiatorname, dest_rtpi);
1632
1633                         spin_lock(&dev->se_port_lock);
1634                         break;
1635                 }
1636                 spin_unlock(&dev->se_port_lock);
1637
1638                 if (!dest_tpg) {
1639                         pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1640                                         " dest_tpg\n");
1641                         ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
1642                         goto out;
1643                 }
1644 #if 0
1645                 pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1646                         " tid_len: %d for %s + %s\n",
1647                         dest_tpg->se_tpg_tfo->get_fabric_name(), cmd->data_length,
1648                         tpdl, tid_len, i_str, iport_ptr);
1649 #endif
1650                 if (tid_len > tpdl) {
1651                         pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1652                                 " %u for Transport ID: %s\n", tid_len, ptr);
1653                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1654                         core_scsi3_tpg_undepend_item(dest_tpg);
1655                         ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
1656                         goto out;
1657                 }
1658                 /*
1659                  * Locate the desintation struct se_dev_entry pointer for matching
1660                  * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1661                  * Target Port.
1662                  */
1663                 dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1664                                         dest_rtpi);
1665                 if (!dest_se_deve) {
1666                         pr_err("Unable to locate %s dest_se_deve"
1667                                 " from destination RTPI: %hu\n",
1668                                 dest_tpg->se_tpg_tfo->get_fabric_name(),
1669                                 dest_rtpi);
1670
1671                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1672                         core_scsi3_tpg_undepend_item(dest_tpg);
1673                         ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
1674                         goto out;
1675                 }
1676
1677                 ret = core_scsi3_lunacl_depend_item(dest_se_deve);
1678                 if (ret < 0) {
1679                         pr_err("core_scsi3_lunacl_depend_item()"
1680                                         " failed\n");
1681                         atomic_dec(&dest_se_deve->pr_ref_count);
1682                         smp_mb__after_atomic_dec();
1683                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1684                         core_scsi3_tpg_undepend_item(dest_tpg);
1685                         ret = PYX_TRANSPORT_LU_COMM_FAILURE;
1686                         goto out;
1687                 }
1688 #if 0
1689                 pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1690                         " dest_se_deve mapped_lun: %u\n",
1691                         dest_tpg->se_tpg_tfo->get_fabric_name(),
1692                         dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1693 #endif
1694                 /*
1695                  * Skip any TransportIDs that already have a registration for
1696                  * this target port.
1697                  */
1698                 pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1699                                         iport_ptr);
1700                 if (pr_reg_e) {
1701                         core_scsi3_put_pr_reg(pr_reg_e);
1702                         core_scsi3_lunacl_undepend_item(dest_se_deve);
1703                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1704                         core_scsi3_tpg_undepend_item(dest_tpg);
1705                         ptr += tid_len;
1706                         tpdl -= tid_len;
1707                         tid_len = 0;
1708                         continue;
1709                 }
1710                 /*
1711                  * Allocate a struct pr_transport_id_holder and setup
1712                  * the dest_node_acl and dest_se_deve pointers for the
1713                  * loop below.
1714                  */
1715                 tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1716                                 GFP_KERNEL);
1717                 if (!tidh_new) {
1718                         pr_err("Unable to allocate tidh_new\n");
1719                         core_scsi3_lunacl_undepend_item(dest_se_deve);
1720                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1721                         core_scsi3_tpg_undepend_item(dest_tpg);
1722                         ret = PYX_TRANSPORT_LU_COMM_FAILURE;
1723                         goto out;
1724                 }
1725                 INIT_LIST_HEAD(&tidh_new->dest_list);
1726                 tidh_new->dest_tpg = dest_tpg;
1727                 tidh_new->dest_node_acl = dest_node_acl;
1728                 tidh_new->dest_se_deve = dest_se_deve;
1729
1730                 /*
1731                  * Allocate, but do NOT add the registration for the
1732                  * TransportID referenced SCSI Initiator port.  This
1733                  * done because of the following from spc4r17 in section
1734                  * 6.14.3 wrt SPEC_I_PT:
1735                  *
1736                  * "If a registration fails for any initiator port (e.g., if th
1737                  * logical unit does not have enough resources available to
1738                  * hold the registration information), no registrations shall be
1739                  * made, and the command shall be terminated with
1740                  * CHECK CONDITION status."
1741                  *
1742                  * That means we call __core_scsi3_alloc_registration() here,
1743                  * and then call __core_scsi3_add_registration() in the
1744                  * 2nd loop which will never fail.
1745                  */
1746                 dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1747                                 dest_node_acl, dest_se_deve, iport_ptr,
1748                                 sa_res_key, all_tg_pt, aptpl);
1749                 if (!dest_pr_reg) {
1750                         core_scsi3_lunacl_undepend_item(dest_se_deve);
1751                         core_scsi3_nodeacl_undepend_item(dest_node_acl);
1752                         core_scsi3_tpg_undepend_item(dest_tpg);
1753                         kfree(tidh_new);
1754                         ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
1755                         goto out;
1756                 }
1757                 tidh_new->dest_pr_reg = dest_pr_reg;
1758                 list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1759
1760                 ptr += tid_len;
1761                 tpdl -= tid_len;
1762                 tid_len = 0;
1763
1764         }
1765
1766         transport_kunmap_first_data_page(cmd);
1767
1768         /*
1769          * Go ahead and create a registrations from tid_dest_list for the
1770          * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1771          * and dest_se_deve.
1772          *
1773          * The SA Reservation Key from the PROUT is set for the
1774          * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1775          * means that the TransportID Initiator port will be
1776          * registered on all of the target ports in the SCSI target device
1777          * ALL_TG_PT=0 means the registration will only be for the
1778          * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1779          * was received.
1780          */
1781         list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1782                 dest_tpg = tidh->dest_tpg;
1783                 dest_node_acl = tidh->dest_node_acl;
1784                 dest_se_deve = tidh->dest_se_deve;
1785                 dest_pr_reg = tidh->dest_pr_reg;
1786                 dest_local_nexus = tidh->dest_local_nexus;
1787
1788                 list_del(&tidh->dest_list);
1789                 kfree(tidh);
1790
1791                 memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1792                 prf_isid = core_pr_dump_initiator_port(dest_pr_reg, &i_buf[0],
1793                                                 PR_REG_ISID_ID_LEN);
1794
1795                 __core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1796                                         dest_pr_reg, 0, 0);
1797
1798                 pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1799                         " registered Transport ID for Node: %s%s Mapped LUN:"
1800                         " %u\n", dest_tpg->se_tpg_tfo->get_fabric_name(),
1801                         dest_node_acl->initiatorname, (prf_isid) ?
1802                         &i_buf[0] : "", dest_se_deve->mapped_lun);
1803
1804                 if (dest_local_nexus)
1805                         continue;
1806
1807                 core_scsi3_lunacl_undepend_item(dest_se_deve);
1808                 core_scsi3_nodeacl_undepend_item(dest_node_acl);
1809                 core_scsi3_tpg_undepend_item(dest_tpg);
1810         }
1811
1812         return 0;
1813 out:
1814         transport_kunmap_first_data_page(cmd);
1815         /*
1816          * For the failure case, release everything from tid_dest_list
1817          * including *dest_pr_reg and the configfs dependances..
1818          */
1819         list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1820                 dest_tpg = tidh->dest_tpg;
1821                 dest_node_acl = tidh->dest_node_acl;
1822                 dest_se_deve = tidh->dest_se_deve;
1823                 dest_pr_reg = tidh->dest_pr_reg;
1824                 dest_local_nexus = tidh->dest_local_nexus;
1825
1826                 list_del(&tidh->dest_list);
1827                 kfree(tidh);
1828                 /*
1829                  * Release any extra ALL_TG_PT=1 registrations for
1830                  * the SPEC_I_PT=1 case.
1831                  */
1832                 list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1833                                 &dest_pr_reg->pr_reg_atp_list,
1834                                 pr_reg_atp_mem_list) {
1835                         list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1836                         core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1837                         kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1838                 }
1839
1840                 kfree(dest_pr_reg->pr_aptpl_buf);
1841                 kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1842
1843                 if (dest_local_nexus)
1844                         continue;
1845
1846                 core_scsi3_lunacl_undepend_item(dest_se_deve);
1847                 core_scsi3_nodeacl_undepend_item(dest_node_acl);
1848                 core_scsi3_tpg_undepend_item(dest_tpg);
1849         }
1850         return ret;
1851 }
1852
1853 /*
1854  * Called with struct se_device->dev_reservation_lock held
1855  */
1856 static int __core_scsi3_update_aptpl_buf(
1857         struct se_device *dev,
1858         unsigned char *buf,
1859         u32 pr_aptpl_buf_len,
1860         int clear_aptpl_metadata)
1861 {
1862         struct se_lun *lun;
1863         struct se_portal_group *tpg;
1864         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1865         struct t10_pr_registration *pr_reg;
1866         unsigned char tmp[512], isid_buf[32];
1867         ssize_t len = 0;
1868         int reg_count = 0;
1869
1870         memset(buf, 0, pr_aptpl_buf_len);
1871         /*
1872          * Called to clear metadata once APTPL has been deactivated.
1873          */
1874         if (clear_aptpl_metadata) {
1875                 snprintf(buf, pr_aptpl_buf_len,
1876                                 "No Registrations or Reservations\n");
1877                 return 0;
1878         }
1879         /*
1880          * Walk the registration list..
1881          */
1882         spin_lock(&su_dev->t10_pr.registration_lock);
1883         list_for_each_entry(pr_reg, &su_dev->t10_pr.registration_list,
1884                         pr_reg_list) {
1885
1886                 tmp[0] = '\0';
1887                 isid_buf[0] = '\0';
1888                 tpg = pr_reg->pr_reg_nacl->se_tpg;
1889                 lun = pr_reg->pr_reg_tg_pt_lun;
1890                 /*
1891                  * Write out any ISID value to APTPL metadata that was included
1892                  * in the original registration.
1893                  */
1894                 if (pr_reg->isid_present_at_reg)
1895                         snprintf(isid_buf, 32, "initiator_sid=%s\n",
1896                                         pr_reg->pr_reg_isid);
1897                 /*
1898                  * Include special metadata if the pr_reg matches the
1899                  * reservation holder.
1900                  */
1901                 if (dev->dev_pr_res_holder == pr_reg) {
1902                         snprintf(tmp, 512, "PR_REG_START: %d"
1903                                 "\ninitiator_fabric=%s\n"
1904                                 "initiator_node=%s\n%s"
1905                                 "sa_res_key=%llu\n"
1906                                 "res_holder=1\nres_type=%02x\n"
1907                                 "res_scope=%02x\nres_all_tg_pt=%d\n"
1908                                 "mapped_lun=%u\n", reg_count,
1909                                 tpg->se_tpg_tfo->get_fabric_name(),
1910                                 pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1911                                 pr_reg->pr_res_key, pr_reg->pr_res_type,
1912                                 pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1913                                 pr_reg->pr_res_mapped_lun);
1914                 } else {
1915                         snprintf(tmp, 512, "PR_REG_START: %d\n"
1916                                 "initiator_fabric=%s\ninitiator_node=%s\n%s"
1917                                 "sa_res_key=%llu\nres_holder=0\n"
1918                                 "res_all_tg_pt=%d\nmapped_lun=%u\n",
1919                                 reg_count, tpg->se_tpg_tfo->get_fabric_name(),
1920                                 pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1921                                 pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1922                                 pr_reg->pr_res_mapped_lun);
1923                 }
1924
1925                 if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1926                         pr_err("Unable to update renaming"
1927                                 " APTPL metadata\n");
1928                         spin_unlock(&su_dev->t10_pr.registration_lock);
1929                         return -EMSGSIZE;
1930                 }
1931                 len += sprintf(buf+len, "%s", tmp);
1932
1933                 /*
1934                  * Include information about the associated SCSI target port.
1935                  */
1936                 snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1937                         "tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%u\nPR_REG_END:"
1938                         " %d\n", tpg->se_tpg_tfo->get_fabric_name(),
1939                         tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1940                         tpg->se_tpg_tfo->tpg_get_tag(tpg),
1941                         lun->lun_sep->sep_rtpi, lun->unpacked_lun, reg_count);
1942
1943                 if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1944                         pr_err("Unable to update renaming"
1945                                 " APTPL metadata\n");
1946                         spin_unlock(&su_dev->t10_pr.registration_lock);
1947                         return -EMSGSIZE;
1948                 }
1949                 len += sprintf(buf+len, "%s", tmp);
1950                 reg_count++;
1951         }
1952         spin_unlock(&su_dev->t10_pr.registration_lock);
1953
1954         if (!reg_count)
1955                 len += sprintf(buf+len, "No Registrations or Reservations");
1956
1957         return 0;
1958 }
1959
1960 static int core_scsi3_update_aptpl_buf(
1961         struct se_device *dev,
1962         unsigned char *buf,
1963         u32 pr_aptpl_buf_len,
1964         int clear_aptpl_metadata)
1965 {
1966         int ret;
1967
1968         spin_lock(&dev->dev_reservation_lock);
1969         ret = __core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len,
1970                                 clear_aptpl_metadata);
1971         spin_unlock(&dev->dev_reservation_lock);
1972
1973         return ret;
1974 }
1975
1976 /*
1977  * Called with struct se_device->aptpl_file_mutex held
1978  */
1979 static int __core_scsi3_write_aptpl_to_file(
1980         struct se_device *dev,
1981         unsigned char *buf,
1982         u32 pr_aptpl_buf_len)
1983 {
1984         struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
1985         struct file *file;
1986         struct iovec iov[1];
1987         mm_segment_t old_fs;
1988         int flags = O_RDWR | O_CREAT | O_TRUNC;
1989         char path[512];
1990         int ret;
1991
1992         memset(iov, 0, sizeof(struct iovec));
1993         memset(path, 0, 512);
1994
1995         if (strlen(&wwn->unit_serial[0]) >= 512) {
1996                 pr_err("WWN value for struct se_device does not fit"
1997                         " into path buffer\n");
1998                 return -EMSGSIZE;
1999         }
2000
2001         snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
2002         file = filp_open(path, flags, 0600);
2003         if (IS_ERR(file) || !file || !file->f_dentry) {
2004                 pr_err("filp_open(%s) for APTPL metadata"
2005                         " failed\n", path);
2006                 return (PTR_ERR(file) < 0 ? PTR_ERR(file) : -ENOENT);
2007         }
2008
2009         iov[0].iov_base = &buf[0];
2010         if (!pr_aptpl_buf_len)
2011                 iov[0].iov_len = (strlen(&buf[0]) + 1); /* Add extra for NULL */
2012         else
2013                 iov[0].iov_len = pr_aptpl_buf_len;
2014
2015         old_fs = get_fs();
2016         set_fs(get_ds());
2017         ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
2018         set_fs(old_fs);
2019
2020         if (ret < 0) {
2021                 pr_debug("Error writing APTPL metadata file: %s\n", path);
2022                 filp_close(file, NULL);
2023                 return -EIO;
2024         }
2025         filp_close(file, NULL);
2026
2027         return 0;
2028 }
2029
2030 static int core_scsi3_update_and_write_aptpl(
2031         struct se_device *dev,
2032         unsigned char *in_buf,
2033         u32 in_pr_aptpl_buf_len)
2034 {
2035         unsigned char null_buf[64], *buf;
2036         u32 pr_aptpl_buf_len;
2037         int ret, clear_aptpl_metadata = 0;
2038         /*
2039          * Can be called with a NULL pointer from PROUT service action CLEAR
2040          */
2041         if (!in_buf) {
2042                 memset(null_buf, 0, 64);
2043                 buf = &null_buf[0];
2044                 /*
2045                  * This will clear the APTPL metadata to:
2046                  * "No Registrations or Reservations" status
2047                  */
2048                 pr_aptpl_buf_len = 64;
2049                 clear_aptpl_metadata = 1;
2050         } else {
2051                 buf = in_buf;
2052                 pr_aptpl_buf_len = in_pr_aptpl_buf_len;
2053         }
2054
2055         ret = core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len,
2056                                 clear_aptpl_metadata);
2057         if (ret != 0)
2058                 return ret;
2059         /*
2060          * __core_scsi3_write_aptpl_to_file() will call strlen()
2061          * on the passed buf to determine pr_aptpl_buf_len.
2062          */
2063         ret = __core_scsi3_write_aptpl_to_file(dev, buf, 0);
2064         if (ret != 0)
2065                 return ret;
2066
2067         return ret;
2068 }
2069
2070 static int core_scsi3_emulate_pro_register(
2071         struct se_cmd *cmd,
2072         u64 res_key,
2073         u64 sa_res_key,
2074         int aptpl,
2075         int all_tg_pt,
2076         int spec_i_pt,
2077         int ignore_key)
2078 {
2079         struct se_session *se_sess = cmd->se_sess;
2080         struct se_device *dev = cmd->se_dev;
2081         struct se_dev_entry *se_deve;
2082         struct se_lun *se_lun = cmd->se_lun;
2083         struct se_portal_group *se_tpg;
2084         struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp, *pr_reg_e;
2085         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2086         /* Used for APTPL metadata w/ UNREGISTER */
2087         unsigned char *pr_aptpl_buf = NULL;
2088         unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2089         int pr_holder = 0, ret = 0, type;
2090
2091         if (!se_sess || !se_lun) {
2092                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2093                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2094         }
2095         se_tpg = se_sess->se_tpg;
2096         se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2097
2098         if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2099                 memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2100                 se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2101                                 PR_REG_ISID_LEN);
2102                 isid_ptr = &isid_buf[0];
2103         }
2104         /*
2105          * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2106          */
2107         pr_reg_e = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2108         if (!pr_reg_e) {
2109                 if (res_key) {
2110                         pr_warn("SPC-3 PR: Reservation Key non-zero"
2111                                 " for SA REGISTER, returning CONFLICT\n");
2112                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
2113                 }
2114                 /*
2115                  * Do nothing but return GOOD status.
2116                  */
2117                 if (!sa_res_key)
2118                         return PYX_TRANSPORT_SENT_TO_TRANSPORT;
2119
2120                 if (!spec_i_pt) {
2121                         /*
2122                          * Perform the Service Action REGISTER on the Initiator
2123                          * Port Endpoint that the PRO was received from on the
2124                          * Logical Unit of the SCSI device server.
2125                          */
2126                         ret = core_scsi3_alloc_registration(cmd->se_dev,
2127                                         se_sess->se_node_acl, se_deve, isid_ptr,
2128                                         sa_res_key, all_tg_pt, aptpl,
2129                                         ignore_key, 0);
2130                         if (ret != 0) {
2131                                 pr_err("Unable to allocate"
2132                                         " struct t10_pr_registration\n");
2133                                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
2134                         }
2135                 } else {
2136                         /*
2137                          * Register both the Initiator port that received
2138                          * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2139                          * TransportID from Parameter list and loop through
2140                          * fabric dependent parameter list while calling
2141                          * logic from of core_scsi3_alloc_registration() for
2142                          * each TransportID provided SCSI Initiator Port/Device
2143                          */
2144                         ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2145                                         isid_ptr, sa_res_key, all_tg_pt, aptpl);
2146                         if (ret != 0)
2147                                 return ret;
2148                 }
2149                 /*
2150                  * Nothing left to do for the APTPL=0 case.
2151                  */
2152                 if (!aptpl) {
2153                         pr_tmpl->pr_aptpl_active = 0;
2154                         core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
2155                         pr_debug("SPC-3 PR: Set APTPL Bit Deactivated for"
2156                                         " REGISTER\n");
2157                         return 0;
2158                 }
2159                 /*
2160                  * Locate the newly allocated local I_T Nexus *pr_reg, and
2161                  * update the APTPL metadata information using its
2162                  * preallocated *pr_reg->pr_aptpl_buf.
2163                  */
2164                 pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev,
2165                                 se_sess->se_node_acl, se_sess);
2166
2167                 ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2168                                 &pr_reg->pr_aptpl_buf[0],
2169                                 pr_tmpl->pr_aptpl_buf_len);
2170                 if (!ret) {
2171                         pr_tmpl->pr_aptpl_active = 1;
2172                         pr_debug("SPC-3 PR: Set APTPL Bit Activated for REGISTER\n");
2173                 }
2174
2175                 core_scsi3_put_pr_reg(pr_reg);
2176                 return ret;
2177         } else {
2178                 /*
2179                  * Locate the existing *pr_reg via struct se_node_acl pointers
2180                  */
2181                 pr_reg = pr_reg_e;
2182                 type = pr_reg->pr_res_type;
2183
2184                 if (!ignore_key) {
2185                         if (res_key != pr_reg->pr_res_key) {
2186                                 pr_err("SPC-3 PR REGISTER: Received"
2187                                         " res_key: 0x%016Lx does not match"
2188                                         " existing SA REGISTER res_key:"
2189                                         " 0x%016Lx\n", res_key,
2190                                         pr_reg->pr_res_key);
2191                                 core_scsi3_put_pr_reg(pr_reg);
2192                                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2193                         }
2194                 }
2195                 if (spec_i_pt) {
2196                         pr_err("SPC-3 PR UNREGISTER: SPEC_I_PT"
2197                                 " set while sa_res_key=0\n");
2198                         core_scsi3_put_pr_reg(pr_reg);
2199                         return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
2200                 }
2201                 /*
2202                  * An existing ALL_TG_PT=1 registration being released
2203                  * must also set ALL_TG_PT=1 in the incoming PROUT.
2204                  */
2205                 if (pr_reg->pr_reg_all_tg_pt && !(all_tg_pt)) {
2206                         pr_err("SPC-3 PR UNREGISTER: ALL_TG_PT=1"
2207                                 " registration exists, but ALL_TG_PT=1 bit not"
2208                                 " present in received PROUT\n");
2209                         core_scsi3_put_pr_reg(pr_reg);
2210                         return PYX_TRANSPORT_INVALID_CDB_FIELD;
2211                 }
2212                 /*
2213                  * Allocate APTPL metadata buffer used for UNREGISTER ops
2214                  */
2215                 if (aptpl) {
2216                         pr_aptpl_buf = kzalloc(pr_tmpl->pr_aptpl_buf_len,
2217                                                 GFP_KERNEL);
2218                         if (!pr_aptpl_buf) {
2219                                 pr_err("Unable to allocate"
2220                                         " pr_aptpl_buf\n");
2221                                 core_scsi3_put_pr_reg(pr_reg);
2222                                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2223                         }
2224                 }
2225                 /*
2226                  * sa_res_key=0 Unregister Reservation Key for registered I_T
2227                  * Nexus sa_res_key=1 Change Reservation Key for registered I_T
2228                  * Nexus.
2229                  */
2230                 if (!sa_res_key) {
2231                         pr_holder = core_scsi3_check_implict_release(
2232                                         cmd->se_dev, pr_reg);
2233                         if (pr_holder < 0) {
2234                                 kfree(pr_aptpl_buf);
2235                                 core_scsi3_put_pr_reg(pr_reg);
2236                                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2237                         }
2238
2239                         spin_lock(&pr_tmpl->registration_lock);
2240                         /*
2241                          * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2242                          * and matching pr_res_key.
2243                          */
2244                         if (pr_reg->pr_reg_all_tg_pt) {
2245                                 list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2246                                                 &pr_tmpl->registration_list,
2247                                                 pr_reg_list) {
2248
2249                                         if (!pr_reg_p->pr_reg_all_tg_pt)
2250                                                 continue;
2251
2252                                         if (pr_reg_p->pr_res_key != res_key)
2253                                                 continue;
2254
2255                                         if (pr_reg == pr_reg_p)
2256                                                 continue;
2257
2258                                         if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2259                                                    pr_reg_p->pr_reg_nacl->initiatorname))
2260                                                 continue;
2261
2262                                         __core_scsi3_free_registration(dev,
2263                                                         pr_reg_p, NULL, 0);
2264                                 }
2265                         }
2266                         /*
2267                          * Release the calling I_T Nexus registration now..
2268                          */
2269                         __core_scsi3_free_registration(cmd->se_dev, pr_reg,
2270                                                         NULL, 1);
2271                         /*
2272                          * From spc4r17, section 5.7.11.3 Unregistering
2273                          *
2274                          * If the persistent reservation is a registrants only
2275                          * type, the device server shall establish a unit
2276                          * attention condition for the initiator port associated
2277                          * with every registered I_T nexus except for the I_T
2278                          * nexus on which the PERSISTENT RESERVE OUT command was
2279                          * received, with the additional sense code set to
2280                          * RESERVATIONS RELEASED.
2281                          */
2282                         if (pr_holder &&
2283                            ((type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
2284                             (type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY))) {
2285                                 list_for_each_entry(pr_reg_p,
2286                                                 &pr_tmpl->registration_list,
2287                                                 pr_reg_list) {
2288
2289                                         core_scsi3_ua_allocate(
2290                                                 pr_reg_p->pr_reg_nacl,
2291                                                 pr_reg_p->pr_res_mapped_lun,
2292                                                 0x2A,
2293                                                 ASCQ_2AH_RESERVATIONS_RELEASED);
2294                                 }
2295                         }
2296                         spin_unlock(&pr_tmpl->registration_lock);
2297
2298                         if (!aptpl) {
2299                                 pr_tmpl->pr_aptpl_active = 0;
2300                                 core_scsi3_update_and_write_aptpl(dev, NULL, 0);
2301                                 pr_debug("SPC-3 PR: Set APTPL Bit Deactivated"
2302                                                 " for UNREGISTER\n");
2303                                 return 0;
2304                         }
2305
2306                         ret = core_scsi3_update_and_write_aptpl(dev,
2307                                         &pr_aptpl_buf[0],
2308                                         pr_tmpl->pr_aptpl_buf_len);
2309                         if (!ret) {
2310                                 pr_tmpl->pr_aptpl_active = 1;
2311                                 pr_debug("SPC-3 PR: Set APTPL Bit Activated"
2312                                                 " for UNREGISTER\n");
2313                         }
2314
2315                         kfree(pr_aptpl_buf);
2316                         return ret;
2317                 } else {
2318                         /*
2319                          * Increment PRgeneration counter for struct se_device"
2320                          * upon a successful REGISTER, see spc4r17 section 6.3.2
2321                          * READ_KEYS service action.
2322                          */
2323                         pr_reg->pr_res_generation = core_scsi3_pr_generation(
2324                                                         cmd->se_dev);
2325                         pr_reg->pr_res_key = sa_res_key;
2326                         pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2327                                 " Key for %s to: 0x%016Lx PRgeneration:"
2328                                 " 0x%08x\n", cmd->se_tfo->get_fabric_name(),
2329                                 (ignore_key) ? "_AND_IGNORE_EXISTING_KEY" : "",
2330                                 pr_reg->pr_reg_nacl->initiatorname,
2331                                 pr_reg->pr_res_key, pr_reg->pr_res_generation);
2332
2333                         if (!aptpl) {
2334                                 pr_tmpl->pr_aptpl_active = 0;
2335                                 core_scsi3_update_and_write_aptpl(dev, NULL, 0);
2336                                 core_scsi3_put_pr_reg(pr_reg);
2337                                 pr_debug("SPC-3 PR: Set APTPL Bit Deactivated"
2338                                                 " for REGISTER\n");
2339                                 return 0;
2340                         }
2341
2342                         ret = core_scsi3_update_and_write_aptpl(dev,
2343                                         &pr_aptpl_buf[0],
2344                                         pr_tmpl->pr_aptpl_buf_len);
2345                         if (!ret) {
2346                                 pr_tmpl->pr_aptpl_active = 1;
2347                                 pr_debug("SPC-3 PR: Set APTPL Bit Activated"
2348                                                 " for REGISTER\n");
2349                         }
2350
2351                         kfree(pr_aptpl_buf);
2352                         core_scsi3_put_pr_reg(pr_reg);
2353                 }
2354         }
2355         return 0;
2356 }
2357
2358 unsigned char *core_scsi3_pr_dump_type(int type)
2359 {
2360         switch (type) {
2361         case PR_TYPE_WRITE_EXCLUSIVE:
2362                 return "Write Exclusive Access";
2363         case PR_TYPE_EXCLUSIVE_ACCESS:
2364                 return "Exclusive Access";
2365         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2366                 return "Write Exclusive Access, Registrants Only";
2367         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2368                 return "Exclusive Access, Registrants Only";
2369         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2370                 return "Write Exclusive Access, All Registrants";
2371         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2372                 return "Exclusive Access, All Registrants";
2373         default:
2374                 break;
2375         }
2376
2377         return "Unknown SPC-3 PR Type";
2378 }
2379
2380 static int core_scsi3_pro_reserve(
2381         struct se_cmd *cmd,
2382         struct se_device *dev,
2383         int type,
2384         int scope,
2385         u64 res_key)
2386 {
2387         struct se_session *se_sess = cmd->se_sess;
2388         struct se_dev_entry *se_deve;
2389         struct se_lun *se_lun = cmd->se_lun;
2390         struct se_portal_group *se_tpg;
2391         struct t10_pr_registration *pr_reg, *pr_res_holder;
2392         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2393         char i_buf[PR_REG_ISID_ID_LEN];
2394         int ret, prf_isid;
2395
2396         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2397
2398         if (!se_sess || !se_lun) {
2399                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2400                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2401         }
2402         se_tpg = se_sess->se_tpg;
2403         se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2404         /*
2405          * Locate the existing *pr_reg via struct se_node_acl pointers
2406          */
2407         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2408                                 se_sess);
2409         if (!pr_reg) {
2410                 pr_err("SPC-3 PR: Unable to locate"
2411                         " PR_REGISTERED *pr_reg for RESERVE\n");
2412                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2413         }
2414         /*
2415          * From spc4r17 Section 5.7.9: Reserving:
2416          *
2417          * An application client creates a persistent reservation by issuing
2418          * a PERSISTENT RESERVE OUT command with RESERVE service action through
2419          * a registered I_T nexus with the following parameters:
2420          *    a) RESERVATION KEY set to the value of the reservation key that is
2421          *       registered with the logical unit for the I_T nexus; and
2422          */
2423         if (res_key != pr_reg->pr_res_key) {
2424                 pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2425                         " does not match existing SA REGISTER res_key:"
2426                         " 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2427                 core_scsi3_put_pr_reg(pr_reg);
2428                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2429         }
2430         /*
2431          * From spc4r17 Section 5.7.9: Reserving:
2432          *
2433          * From above:
2434          *  b) TYPE field and SCOPE field set to the persistent reservation
2435          *     being created.
2436          *
2437          * Only one persistent reservation is allowed at a time per logical unit
2438          * and that persistent reservation has a scope of LU_SCOPE.
2439          */
2440         if (scope != PR_SCOPE_LU_SCOPE) {
2441                 pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2442                 core_scsi3_put_pr_reg(pr_reg);
2443                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
2444         }
2445         /*
2446          * See if we have an existing PR reservation holder pointer at
2447          * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2448          * *pr_res_holder.
2449          */
2450         spin_lock(&dev->dev_reservation_lock);
2451         pr_res_holder = dev->dev_pr_res_holder;
2452         if ((pr_res_holder)) {
2453                 /*
2454                  * From spc4r17 Section 5.7.9: Reserving:
2455                  *
2456                  * If the device server receives a PERSISTENT RESERVE OUT
2457                  * command from an I_T nexus other than a persistent reservation
2458                  * holder (see 5.7.10) that attempts to create a persistent
2459                  * reservation when a persistent reservation already exists for
2460                  * the logical unit, then the command shall be completed with
2461                  * RESERVATION CONFLICT status.
2462                  */
2463                 if (pr_res_holder != pr_reg) {
2464                         struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2465                         pr_err("SPC-3 PR: Attempted RESERVE from"
2466                                 " [%s]: %s while reservation already held by"
2467                                 " [%s]: %s, returning RESERVATION_CONFLICT\n",
2468                                 cmd->se_tfo->get_fabric_name(),
2469                                 se_sess->se_node_acl->initiatorname,
2470                                 pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2471                                 pr_res_holder->pr_reg_nacl->initiatorname);
2472
2473                         spin_unlock(&dev->dev_reservation_lock);
2474                         core_scsi3_put_pr_reg(pr_reg);
2475                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
2476                 }
2477                 /*
2478                  * From spc4r17 Section 5.7.9: Reserving:
2479                  *
2480                  * If a persistent reservation holder attempts to modify the
2481                  * type or scope of an existing persistent reservation, the
2482                  * command shall be completed with RESERVATION CONFLICT status.
2483                  */
2484                 if ((pr_res_holder->pr_res_type != type) ||
2485                     (pr_res_holder->pr_res_scope != scope)) {
2486                         struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2487                         pr_err("SPC-3 PR: Attempted RESERVE from"
2488                                 " [%s]: %s trying to change TYPE and/or SCOPE,"
2489                                 " while reservation already held by [%s]: %s,"
2490                                 " returning RESERVATION_CONFLICT\n",
2491                                 cmd->se_tfo->get_fabric_name(),
2492                                 se_sess->se_node_acl->initiatorname,
2493                                 pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2494                                 pr_res_holder->pr_reg_nacl->initiatorname);
2495
2496                         spin_unlock(&dev->dev_reservation_lock);
2497                         core_scsi3_put_pr_reg(pr_reg);
2498                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
2499                 }
2500                 /*
2501                  * From spc4r17 Section 5.7.9: Reserving:
2502                  *
2503                  * If the device server receives a PERSISTENT RESERVE OUT
2504                  * command with RESERVE service action where the TYPE field and
2505                  * the SCOPE field contain the same values as the existing type
2506                  * and scope from a persistent reservation holder, it shall not
2507                  * make any change to the existing persistent reservation and
2508                  * shall completethe command with GOOD status.
2509                  */
2510                 spin_unlock(&dev->dev_reservation_lock);
2511                 core_scsi3_put_pr_reg(pr_reg);
2512                 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
2513         }
2514         /*
2515          * Otherwise, our *pr_reg becomes the PR reservation holder for said
2516          * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2517          */
2518         pr_reg->pr_res_scope = scope;
2519         pr_reg->pr_res_type = type;
2520         pr_reg->pr_res_holder = 1;
2521         dev->dev_pr_res_holder = pr_reg;
2522         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2523                                 PR_REG_ISID_ID_LEN);
2524
2525         pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2526                 " reservation holder TYPE: %s ALL_TG_PT: %d\n",
2527                 cmd->se_tfo->get_fabric_name(), core_scsi3_pr_dump_type(type),
2528                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2529         pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2530                         cmd->se_tfo->get_fabric_name(),
2531                         se_sess->se_node_acl->initiatorname,
2532                         (prf_isid) ? &i_buf[0] : "");
2533         spin_unlock(&dev->dev_reservation_lock);
2534
2535         if (pr_tmpl->pr_aptpl_active) {
2536                 ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2537                                 &pr_reg->pr_aptpl_buf[0],
2538                                 pr_tmpl->pr_aptpl_buf_len);
2539                 if (!ret)
2540                         pr_debug("SPC-3 PR: Updated APTPL metadata"
2541                                         " for RESERVE\n");
2542         }
2543
2544         core_scsi3_put_pr_reg(pr_reg);
2545         return 0;
2546 }
2547
2548 static int core_scsi3_emulate_pro_reserve(
2549         struct se_cmd *cmd,
2550         int type,
2551         int scope,
2552         u64 res_key)
2553 {
2554         struct se_device *dev = cmd->se_dev;
2555         int ret = 0;
2556
2557         switch (type) {
2558         case PR_TYPE_WRITE_EXCLUSIVE:
2559         case PR_TYPE_EXCLUSIVE_ACCESS:
2560         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2561         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2562         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2563         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2564                 ret = core_scsi3_pro_reserve(cmd, dev, type, scope, res_key);
2565                 break;
2566         default:
2567                 pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2568                         " 0x%02x\n", type);
2569                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
2570         }
2571
2572         return ret;
2573 }
2574
2575 /*
2576  * Called with struct se_device->dev_reservation_lock held.
2577  */
2578 static void __core_scsi3_complete_pro_release(
2579         struct se_device *dev,
2580         struct se_node_acl *se_nacl,
2581         struct t10_pr_registration *pr_reg,
2582         int explict)
2583 {
2584         struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2585         char i_buf[PR_REG_ISID_ID_LEN];
2586         int prf_isid;
2587
2588         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2589         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2590                                 PR_REG_ISID_ID_LEN);
2591         /*
2592          * Go ahead and release the current PR reservation holder.
2593          */
2594         dev->dev_pr_res_holder = NULL;
2595
2596         pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2597                 " reservation holder TYPE: %s ALL_TG_PT: %d\n",
2598                 tfo->get_fabric_name(), (explict) ? "explict" : "implict",
2599                 core_scsi3_pr_dump_type(pr_reg->pr_res_type),
2600                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2601         pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2602                 tfo->get_fabric_name(), se_nacl->initiatorname,
2603                 (prf_isid) ? &i_buf[0] : "");
2604         /*
2605          * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2606          */
2607         pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2608 }
2609
2610 static int core_scsi3_emulate_pro_release(
2611         struct se_cmd *cmd,
2612         int type,
2613         int scope,
2614         u64 res_key)
2615 {
2616         struct se_device *dev = cmd->se_dev;
2617         struct se_session *se_sess = cmd->se_sess;
2618         struct se_lun *se_lun = cmd->se_lun;
2619         struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2620         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2621         int ret, all_reg = 0;
2622
2623         if (!se_sess || !se_lun) {
2624                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2625                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2626         }
2627         /*
2628          * Locate the existing *pr_reg via struct se_node_acl pointers
2629          */
2630         pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2631         if (!pr_reg) {
2632                 pr_err("SPC-3 PR: Unable to locate"
2633                         " PR_REGISTERED *pr_reg for RELEASE\n");
2634                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2635         }
2636         /*
2637          * From spc4r17 Section 5.7.11.2 Releasing:
2638          *
2639          * If there is no persistent reservation or in response to a persistent
2640          * reservation release request from a registered I_T nexus that is not a
2641          * persistent reservation holder (see 5.7.10), the device server shall
2642          * do the following:
2643          *
2644          *     a) Not release the persistent reservation, if any;
2645          *     b) Not remove any registrations; and
2646          *     c) Complete the command with GOOD status.
2647          */
2648         spin_lock(&dev->dev_reservation_lock);
2649         pr_res_holder = dev->dev_pr_res_holder;
2650         if (!pr_res_holder) {
2651                 /*
2652                  * No persistent reservation, return GOOD status.
2653                  */
2654                 spin_unlock(&dev->dev_reservation_lock);
2655                 core_scsi3_put_pr_reg(pr_reg);
2656                 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
2657         }
2658         if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2659             (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
2660                 all_reg = 1;
2661
2662         if ((all_reg == 0) && (pr_res_holder != pr_reg)) {
2663                 /*
2664                  * Non 'All Registrants' PR Type cases..
2665                  * Release request from a registered I_T nexus that is not a
2666                  * persistent reservation holder. return GOOD status.
2667                  */
2668                 spin_unlock(&dev->dev_reservation_lock);
2669                 core_scsi3_put_pr_reg(pr_reg);
2670                 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
2671         }
2672         /*
2673          * From spc4r17 Section 5.7.11.2 Releasing:
2674          *
2675          * Only the persistent reservation holder (see 5.7.10) is allowed to
2676          * release a persistent reservation.
2677          *
2678          * An application client releases the persistent reservation by issuing
2679          * a PERSISTENT RESERVE OUT command with RELEASE service action through
2680          * an I_T nexus that is a persistent reservation holder with the
2681          * following parameters:
2682          *
2683          *     a) RESERVATION KEY field set to the value of the reservation key
2684          *        that is registered with the logical unit for the I_T nexus;
2685          */
2686         if (res_key != pr_reg->pr_res_key) {
2687                 pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2688                         " does not match existing SA REGISTER res_key:"
2689                         " 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2690                 spin_unlock(&dev->dev_reservation_lock);
2691                 core_scsi3_put_pr_reg(pr_reg);
2692                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2693         }
2694         /*
2695          * From spc4r17 Section 5.7.11.2 Releasing and above:
2696          *
2697          * b) TYPE field and SCOPE field set to match the persistent
2698          *    reservation being released.
2699          */
2700         if ((pr_res_holder->pr_res_type != type) ||
2701             (pr_res_holder->pr_res_scope != scope)) {
2702                 struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2703                 pr_err("SPC-3 PR RELEASE: Attempted to release"
2704                         " reservation from [%s]: %s with different TYPE "
2705                         "and/or SCOPE  while reservation already held by"
2706                         " [%s]: %s, returning RESERVATION_CONFLICT\n",
2707                         cmd->se_tfo->get_fabric_name(),
2708                         se_sess->se_node_acl->initiatorname,
2709                         pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2710                         pr_res_holder->pr_reg_nacl->initiatorname);
2711
2712                 spin_unlock(&dev->dev_reservation_lock);
2713                 core_scsi3_put_pr_reg(pr_reg);
2714                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2715         }
2716         /*
2717          * In response to a persistent reservation release request from the
2718          * persistent reservation holder the device server shall perform a
2719          * release by doing the following as an uninterrupted series of actions:
2720          * a) Release the persistent reservation;
2721          * b) Not remove any registration(s);
2722          * c) If the released persistent reservation is a registrants only type
2723          * or all registrants type persistent reservation,
2724          *    the device server shall establish a unit attention condition for
2725          *    the initiator port associated with every regis-
2726          *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2727          *    RESERVE OUT command with RELEASE service action was received,
2728          *    with the additional sense code set to RESERVATIONS RELEASED; and
2729          * d) If the persistent reservation is of any other type, the device
2730          *    server shall not establish a unit attention condition.
2731          */
2732         __core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2733                         pr_reg, 1);
2734
2735         spin_unlock(&dev->dev_reservation_lock);
2736
2737         if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2738             (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2739             (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2740             (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2741                 /*
2742                  * If no UNIT ATTENTION conditions will be established for
2743                  * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2744                  * go ahead and check for APTPL=1 update+write below
2745                  */
2746                 goto write_aptpl;
2747         }
2748
2749         spin_lock(&pr_tmpl->registration_lock);
2750         list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2751                         pr_reg_list) {
2752                 /*
2753                  * Do not establish a UNIT ATTENTION condition
2754                  * for the calling I_T Nexus
2755                  */
2756                 if (pr_reg_p == pr_reg)
2757                         continue;
2758
2759                 core_scsi3_ua_allocate(pr_reg_p->pr_reg_nacl,
2760                                 pr_reg_p->pr_res_mapped_lun,
2761                                 0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2762         }
2763         spin_unlock(&pr_tmpl->registration_lock);
2764
2765 write_aptpl:
2766         if (pr_tmpl->pr_aptpl_active) {
2767                 ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2768                                 &pr_reg->pr_aptpl_buf[0],
2769                                 pr_tmpl->pr_aptpl_buf_len);
2770                 if (!ret)
2771                         pr_debug("SPC-3 PR: Updated APTPL metadata for RELEASE\n");
2772         }
2773
2774         core_scsi3_put_pr_reg(pr_reg);
2775         return 0;
2776 }
2777
2778 static int core_scsi3_emulate_pro_clear(
2779         struct se_cmd *cmd,
2780         u64 res_key)
2781 {
2782         struct se_device *dev = cmd->se_dev;
2783         struct se_node_acl *pr_reg_nacl;
2784         struct se_session *se_sess = cmd->se_sess;
2785         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2786         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2787         u32 pr_res_mapped_lun = 0;
2788         int calling_it_nexus = 0;
2789         /*
2790          * Locate the existing *pr_reg via struct se_node_acl pointers
2791          */
2792         pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2793                         se_sess->se_node_acl, se_sess);
2794         if (!pr_reg_n) {
2795                 pr_err("SPC-3 PR: Unable to locate"
2796                         " PR_REGISTERED *pr_reg for CLEAR\n");
2797                         return PYX_TRANSPORT_LU_COMM_FAILURE;
2798         }
2799         /*
2800          * From spc4r17 section 5.7.11.6, Clearing:
2801          *
2802          * Any application client may release the persistent reservation and
2803          * remove all registrations from a device server by issuing a
2804          * PERSISTENT RESERVE OUT command with CLEAR service action through a
2805          * registered I_T nexus with the following parameter:
2806          *
2807          *      a) RESERVATION KEY field set to the value of the reservation key
2808          *         that is registered with the logical unit for the I_T nexus.
2809          */
2810         if (res_key != pr_reg_n->pr_res_key) {
2811                 pr_err("SPC-3 PR REGISTER: Received"
2812                         " res_key: 0x%016Lx does not match"
2813                         " existing SA REGISTER res_key:"
2814                         " 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2815                 core_scsi3_put_pr_reg(pr_reg_n);
2816                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2817         }
2818         /*
2819          * a) Release the persistent reservation, if any;
2820          */
2821         spin_lock(&dev->dev_reservation_lock);
2822         pr_res_holder = dev->dev_pr_res_holder;
2823         if (pr_res_holder) {
2824                 struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2825                 __core_scsi3_complete_pro_release(dev, pr_res_nacl,
2826                         pr_res_holder, 0);
2827         }
2828         spin_unlock(&dev->dev_reservation_lock);
2829         /*
2830          * b) Remove all registration(s) (see spc4r17 5.7.7);
2831          */
2832         spin_lock(&pr_tmpl->registration_lock);
2833         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2834                         &pr_tmpl->registration_list, pr_reg_list) {
2835
2836                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2837                 pr_reg_nacl = pr_reg->pr_reg_nacl;
2838                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2839                 __core_scsi3_free_registration(dev, pr_reg, NULL,
2840                                         calling_it_nexus);
2841                 /*
2842                  * e) Establish a unit attention condition for the initiator
2843                  *    port associated with every registered I_T nexus other
2844                  *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2845                  *    command with CLEAR service action was received, with the
2846                  *    additional sense code set to RESERVATIONS PREEMPTED.
2847                  */
2848                 if (!calling_it_nexus)
2849                         core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun,
2850                                 0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2851         }
2852         spin_unlock(&pr_tmpl->registration_lock);
2853
2854         pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2855                 cmd->se_tfo->get_fabric_name());
2856
2857         if (pr_tmpl->pr_aptpl_active) {
2858                 core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
2859                 pr_debug("SPC-3 PR: Updated APTPL metadata"
2860                                 " for CLEAR\n");
2861         }
2862
2863         core_scsi3_pr_generation(dev);
2864         return 0;
2865 }
2866
2867 /*
2868  * Called with struct se_device->dev_reservation_lock held.
2869  */
2870 static void __core_scsi3_complete_pro_preempt(
2871         struct se_device *dev,
2872         struct t10_pr_registration *pr_reg,
2873         struct list_head *preempt_and_abort_list,
2874         int type,
2875         int scope,
2876         int abort)
2877 {
2878         struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2879         struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2880         char i_buf[PR_REG_ISID_ID_LEN];
2881         int prf_isid;
2882
2883         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2884         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2885                                 PR_REG_ISID_ID_LEN);
2886         /*
2887          * Do an implict RELEASE of the existing reservation.
2888          */
2889         if (dev->dev_pr_res_holder)
2890                 __core_scsi3_complete_pro_release(dev, nacl,
2891                                 dev->dev_pr_res_holder, 0);
2892
2893         dev->dev_pr_res_holder = pr_reg;
2894         pr_reg->pr_res_holder = 1;
2895         pr_reg->pr_res_type = type;
2896         pr_reg->pr_res_scope = scope;
2897
2898         pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2899                 " reservation holder TYPE: %s ALL_TG_PT: %d\n",
2900                 tfo->get_fabric_name(), (abort) ? "_AND_ABORT" : "",
2901                 core_scsi3_pr_dump_type(type),
2902                 (pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2903         pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2904                 tfo->get_fabric_name(), (abort) ? "_AND_ABORT" : "",
2905                 nacl->initiatorname, (prf_isid) ? &i_buf[0] : "");
2906         /*
2907          * For PREEMPT_AND_ABORT, add the preempting reservation's
2908          * struct t10_pr_registration to the list that will be compared
2909          * against received CDBs..
2910          */
2911         if (preempt_and_abort_list)
2912                 list_add_tail(&pr_reg->pr_reg_abort_list,
2913                                 preempt_and_abort_list);
2914 }
2915
2916 static void core_scsi3_release_preempt_and_abort(
2917         struct list_head *preempt_and_abort_list,
2918         struct t10_pr_registration *pr_reg_holder)
2919 {
2920         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2921
2922         list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2923                                 pr_reg_abort_list) {
2924
2925                 list_del(&pr_reg->pr_reg_abort_list);
2926                 if (pr_reg_holder == pr_reg)
2927                         continue;
2928                 if (pr_reg->pr_res_holder) {
2929                         pr_warn("pr_reg->pr_res_holder still set\n");
2930                         continue;
2931                 }
2932
2933                 pr_reg->pr_reg_deve = NULL;
2934                 pr_reg->pr_reg_nacl = NULL;
2935                 kfree(pr_reg->pr_aptpl_buf);
2936                 kmem_cache_free(t10_pr_reg_cache, pr_reg);
2937         }
2938 }
2939
2940 int core_scsi3_check_cdb_abort_and_preempt(
2941         struct list_head *preempt_and_abort_list,
2942         struct se_cmd *cmd)
2943 {
2944         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2945
2946         list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2947                                 pr_reg_abort_list) {
2948                 if (pr_reg->pr_res_key == cmd->pr_res_key)
2949                         return 0;
2950         }
2951
2952         return 1;
2953 }
2954
2955 static int core_scsi3_pro_preempt(
2956         struct se_cmd *cmd,
2957         int type,
2958         int scope,
2959         u64 res_key,
2960         u64 sa_res_key,
2961         int abort)
2962 {
2963         struct se_device *dev = cmd->se_dev;
2964         struct se_dev_entry *se_deve;
2965         struct se_node_acl *pr_reg_nacl;
2966         struct se_session *se_sess = cmd->se_sess;
2967         struct list_head preempt_and_abort_list;
2968         struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2969         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2970         u32 pr_res_mapped_lun = 0;
2971         int all_reg = 0, calling_it_nexus = 0, released_regs = 0;
2972         int prh_type = 0, prh_scope = 0, ret;
2973
2974         if (!se_sess)
2975                 return PYX_TRANSPORT_LU_COMM_FAILURE;
2976
2977         se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2978         pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2979                                 se_sess);
2980         if (!pr_reg_n) {
2981                 pr_err("SPC-3 PR: Unable to locate"
2982                         " PR_REGISTERED *pr_reg for PREEMPT%s\n",
2983                         (abort) ? "_AND_ABORT" : "");
2984                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2985         }
2986         if (pr_reg_n->pr_res_key != res_key) {
2987                 core_scsi3_put_pr_reg(pr_reg_n);
2988                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
2989         }
2990         if (scope != PR_SCOPE_LU_SCOPE) {
2991                 pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2992                 core_scsi3_put_pr_reg(pr_reg_n);
2993                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
2994         }
2995         INIT_LIST_HEAD(&preempt_and_abort_list);
2996
2997         spin_lock(&dev->dev_reservation_lock);
2998         pr_res_holder = dev->dev_pr_res_holder;
2999         if (pr_res_holder &&
3000            ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3001             (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
3002                 all_reg = 1;
3003
3004         if (!all_reg && !sa_res_key) {
3005                 spin_unlock(&dev->dev_reservation_lock);
3006                 core_scsi3_put_pr_reg(pr_reg_n);
3007                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3008         }
3009         /*
3010          * From spc4r17, section 5.7.11.4.4 Removing Registrations:
3011          *
3012          * If the SERVICE ACTION RESERVATION KEY field does not identify a
3013          * persistent reservation holder or there is no persistent reservation
3014          * holder (i.e., there is no persistent reservation), then the device
3015          * server shall perform a preempt by doing the following in an
3016          * uninterrupted series of actions. (See below..)
3017          */
3018         if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
3019                 /*
3020                  * No existing or SA Reservation Key matching reservations..
3021                  *
3022                  * PROUT SA PREEMPT with All Registrant type reservations are
3023                  * allowed to be processed without a matching SA Reservation Key
3024                  */
3025                 spin_lock(&pr_tmpl->registration_lock);
3026                 list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3027                                 &pr_tmpl->registration_list, pr_reg_list) {
3028                         /*
3029                          * Removing of registrations in non all registrants
3030                          * type reservations without a matching SA reservation
3031                          * key.
3032                          *
3033                          * a) Remove the registrations for all I_T nexuses
3034                          *    specified by the SERVICE ACTION RESERVATION KEY
3035                          *    field;
3036                          * b) Ignore the contents of the SCOPE and TYPE fields;
3037                          * c) Process tasks as defined in 5.7.1; and
3038                          * d) Establish a unit attention condition for the
3039                          *    initiator port associated with every I_T nexus
3040                          *    that lost its registration other than the I_T
3041                          *    nexus on which the PERSISTENT RESERVE OUT command
3042                          *    was received, with the additional sense code set
3043                          *    to REGISTRATIONS PREEMPTED.
3044                          */
3045                         if (!all_reg) {
3046                                 if (pr_reg->pr_res_key != sa_res_key)
3047                                         continue;
3048
3049                                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3050                                 pr_reg_nacl = pr_reg->pr_reg_nacl;
3051                                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3052                                 __core_scsi3_free_registration(dev, pr_reg,
3053                                         (abort) ? &preempt_and_abort_list :
3054                                                 NULL, calling_it_nexus);
3055                                 released_regs++;
3056                         } else {
3057                                 /*
3058                                  * Case for any existing all registrants type
3059                                  * reservation, follow logic in spc4r17 section
3060                                  * 5.7.11.4 Preempting, Table 52 and Figure 7.
3061                                  *
3062                                  * For a ZERO SA Reservation key, release
3063                                  * all other registrations and do an implict
3064                                  * release of active persistent reservation.
3065                                  *
3066                                  * For a non-ZERO SA Reservation key, only
3067                                  * release the matching reservation key from
3068                                  * registrations.
3069                                  */
3070                                 if ((sa_res_key) &&
3071                                      (pr_reg->pr_res_key != sa_res_key))
3072                                         continue;
3073
3074                                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3075                                 if (calling_it_nexus)
3076                                         continue;
3077
3078                                 pr_reg_nacl = pr_reg->pr_reg_nacl;
3079                                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3080                                 __core_scsi3_free_registration(dev, pr_reg,
3081                                         (abort) ? &preempt_and_abort_list :
3082                                                 NULL, 0);
3083                                 released_regs++;
3084                         }
3085                         if (!calling_it_nexus)
3086                                 core_scsi3_ua_allocate(pr_reg_nacl,
3087                                         pr_res_mapped_lun, 0x2A,
3088                                         ASCQ_2AH_RESERVATIONS_PREEMPTED);
3089                 }
3090                 spin_unlock(&pr_tmpl->registration_lock);
3091                 /*
3092                  * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
3093                  * a PREEMPT AND ABORT service action sets the SERVICE ACTION
3094                  * RESERVATION KEY field to a value that does not match any
3095                  * registered reservation key, then the device server shall
3096                  * complete the command with RESERVATION CONFLICT status.
3097                  */
3098                 if (!released_regs) {
3099                         spin_unlock(&dev->dev_reservation_lock);
3100                         core_scsi3_put_pr_reg(pr_reg_n);
3101                         return PYX_TRANSPORT_RESERVATION_CONFLICT;
3102                 }
3103                 /*
3104                  * For an existing all registrants type reservation
3105                  * with a zero SA rservation key, preempt the existing
3106                  * reservation with the new PR type and scope.
3107                  */
3108                 if (pr_res_holder && all_reg && !(sa_res_key)) {
3109                         __core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3110                                 (abort) ? &preempt_and_abort_list : NULL,
3111                                 type, scope, abort);
3112
3113                         if (abort)
3114                                 core_scsi3_release_preempt_and_abort(
3115                                         &preempt_and_abort_list, pr_reg_n);
3116                 }
3117                 spin_unlock(&dev->dev_reservation_lock);
3118
3119                 if (pr_tmpl->pr_aptpl_active) {
3120                         ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3121                                         &pr_reg_n->pr_aptpl_buf[0],
3122                                         pr_tmpl->pr_aptpl_buf_len);
3123                         if (!ret)
3124                                 pr_debug("SPC-3 PR: Updated APTPL"
3125                                         " metadata for  PREEMPT%s\n", (abort) ?
3126                                         "_AND_ABORT" : "");
3127                 }
3128
3129                 core_scsi3_put_pr_reg(pr_reg_n);
3130                 core_scsi3_pr_generation(cmd->se_dev);
3131                 return 0;
3132         }
3133         /*
3134          * The PREEMPTing SA reservation key matches that of the
3135          * existing persistent reservation, first, we check if
3136          * we are preempting our own reservation.
3137          * From spc4r17, section 5.7.11.4.3 Preempting
3138          * persistent reservations and registration handling
3139          *
3140          * If an all registrants persistent reservation is not
3141          * present, it is not an error for the persistent
3142          * reservation holder to preempt itself (i.e., a
3143          * PERSISTENT RESERVE OUT with a PREEMPT service action
3144          * or a PREEMPT AND ABORT service action with the
3145          * SERVICE ACTION RESERVATION KEY value equal to the
3146          * persistent reservation holder's reservation key that
3147          * is received from the persistent reservation holder).
3148          * In that case, the device server shall establish the
3149          * new persistent reservation and maintain the
3150          * registration.
3151          */
3152         prh_type = pr_res_holder->pr_res_type;
3153         prh_scope = pr_res_holder->pr_res_scope;
3154         /*
3155          * If the SERVICE ACTION RESERVATION KEY field identifies a
3156          * persistent reservation holder (see 5.7.10), the device
3157          * server shall perform a preempt by doing the following as
3158          * an uninterrupted series of actions:
3159          *
3160          * a) Release the persistent reservation for the holder
3161          *    identified by the SERVICE ACTION RESERVATION KEY field;
3162          */
3163         if (pr_reg_n != pr_res_holder)
3164                 __core_scsi3_complete_pro_release(dev,
3165                                 pr_res_holder->pr_reg_nacl,
3166                                 dev->dev_pr_res_holder, 0);
3167         /*
3168          * b) Remove the registrations for all I_T nexuses identified
3169          *    by the SERVICE ACTION RESERVATION KEY field, except the
3170          *    I_T nexus that is being used for the PERSISTENT RESERVE
3171          *    OUT command. If an all registrants persistent reservation
3172          *    is present and the SERVICE ACTION RESERVATION KEY field
3173          *    is set to zero, then all registrations shall be removed
3174          *    except for that of the I_T nexus that is being used for
3175          *    the PERSISTENT RESERVE OUT command;
3176          */
3177         spin_lock(&pr_tmpl->registration_lock);
3178         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3179                         &pr_tmpl->registration_list, pr_reg_list) {
3180
3181                 calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3182                 if (calling_it_nexus)
3183                         continue;
3184
3185                 if (pr_reg->pr_res_key != sa_res_key)
3186                         continue;
3187
3188                 pr_reg_nacl = pr_reg->pr_reg_nacl;
3189                 pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3190                 __core_scsi3_free_registration(dev, pr_reg,
3191                                 (abort) ? &preempt_and_abort_list : NULL,
3192                                 calling_it_nexus);
3193                 /*
3194                  * e) Establish a unit attention condition for the initiator
3195                  *    port associated with every I_T nexus that lost its
3196                  *    persistent reservation and/or registration, with the
3197                  *    additional sense code set to REGISTRATIONS PREEMPTED;
3198                  */
3199                 core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3200                                 ASCQ_2AH_RESERVATIONS_PREEMPTED);
3201         }
3202         spin_unlock(&pr_tmpl->registration_lock);
3203         /*
3204          * c) Establish a persistent reservation for the preempting
3205          *    I_T nexus using the contents of the SCOPE and TYPE fields;
3206          */
3207         __core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3208                         (abort) ? &preempt_and_abort_list : NULL,
3209                         type, scope, abort);
3210         /*
3211          * d) Process tasks as defined in 5.7.1;
3212          * e) See above..
3213          * f) If the type or scope has changed, then for every I_T nexus
3214          *    whose reservation key was not removed, except for the I_T
3215          *    nexus on which the PERSISTENT RESERVE OUT command was
3216          *    received, the device server shall establish a unit
3217          *    attention condition for the initiator port associated with
3218          *    that I_T nexus, with the additional sense code set to
3219          *    RESERVATIONS RELEASED. If the type or scope have not
3220          *    changed, then no unit attention condition(s) shall be
3221          *    established for this reason.
3222          */
3223         if ((prh_type != type) || (prh_scope != scope)) {
3224                 spin_lock(&pr_tmpl->registration_lock);
3225                 list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3226                                 &pr_tmpl->registration_list, pr_reg_list) {
3227
3228                         calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3229                         if (calling_it_nexus)
3230                                 continue;
3231
3232                         core_scsi3_ua_allocate(pr_reg->pr_reg_nacl,
3233                                         pr_reg->pr_res_mapped_lun, 0x2A,
3234                                         ASCQ_2AH_RESERVATIONS_RELEASED);
3235                 }
3236                 spin_unlock(&pr_tmpl->registration_lock);
3237         }
3238         spin_unlock(&dev->dev_reservation_lock);
3239         /*
3240          * Call LUN_RESET logic upon list of struct t10_pr_registration,
3241          * All received CDBs for the matching existing reservation and
3242          * registrations undergo ABORT_TASK logic.
3243          *
3244          * From there, core_scsi3_release_preempt_and_abort() will
3245          * release every registration in the list (which have already
3246          * been removed from the primary pr_reg list), except the
3247          * new persistent reservation holder, the calling Initiator Port.
3248          */
3249         if (abort) {
3250                 core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3251                 core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3252                                                 pr_reg_n);
3253         }
3254
3255         if (pr_tmpl->pr_aptpl_active) {
3256                 ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3257                                 &pr_reg_n->pr_aptpl_buf[0],
3258                                 pr_tmpl->pr_aptpl_buf_len);
3259                 if (!ret)
3260                         pr_debug("SPC-3 PR: Updated APTPL metadata for PREEMPT"
3261                                 "%s\n", (abort) ? "_AND_ABORT" : "");
3262         }
3263
3264         core_scsi3_put_pr_reg(pr_reg_n);
3265         core_scsi3_pr_generation(cmd->se_dev);
3266         return 0;
3267 }
3268
3269 static int core_scsi3_emulate_pro_preempt(
3270         struct se_cmd *cmd,
3271         int type,
3272         int scope,
3273         u64 res_key,
3274         u64 sa_res_key,
3275         int abort)
3276 {
3277         int ret = 0;
3278
3279         switch (type) {
3280         case PR_TYPE_WRITE_EXCLUSIVE:
3281         case PR_TYPE_EXCLUSIVE_ACCESS:
3282         case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3283         case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3284         case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3285         case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3286                 ret = core_scsi3_pro_preempt(cmd, type, scope,
3287                                 res_key, sa_res_key, abort);
3288                 break;
3289         default:
3290                 pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3291                         " Type: 0x%02x\n", (abort) ? "_AND_ABORT" : "", type);
3292                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
3293         }
3294
3295         return ret;
3296 }
3297
3298
3299 static int core_scsi3_emulate_pro_register_and_move(
3300         struct se_cmd *cmd,
3301         u64 res_key,
3302         u64 sa_res_key,
3303         int aptpl,
3304         int unreg)
3305 {
3306         struct se_session *se_sess = cmd->se_sess;
3307         struct se_device *dev = cmd->se_dev;
3308         struct se_dev_entry *se_deve, *dest_se_deve = NULL;
3309         struct se_lun *se_lun = cmd->se_lun;
3310         struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3311         struct se_port *se_port;
3312         struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3313         struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3314         struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3315         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
3316         unsigned char *buf;
3317         unsigned char *initiator_str;
3318         char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
3319         u32 tid_len, tmp_tid_len;
3320         int new_reg = 0, type, scope, ret, matching_iname, prf_isid;
3321         unsigned short rtpi;
3322         unsigned char proto_ident;
3323
3324         if (!se_sess || !se_lun) {
3325                 pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3326                 return PYX_TRANSPORT_LU_COMM_FAILURE;
3327         }
3328         memset(dest_iport, 0, 64);
3329         memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3330         se_tpg = se_sess->se_tpg;
3331         tf_ops = se_tpg->se_tpg_tfo;
3332         se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
3333         /*
3334          * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3335          *      Register behaviors for a REGISTER AND MOVE service action
3336          *
3337          * Locate the existing *pr_reg via struct se_node_acl pointers
3338          */
3339         pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3340                                 se_sess);
3341         if (!pr_reg) {
3342                 pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3343                         " *pr_reg for REGISTER_AND_MOVE\n");
3344                 return PYX_TRANSPORT_LU_COMM_FAILURE;
3345         }
3346         /*
3347          * The provided reservation key much match the existing reservation key
3348          * provided during this initiator's I_T nexus registration.
3349          */
3350         if (res_key != pr_reg->pr_res_key) {
3351                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3352                         " res_key: 0x%016Lx does not match existing SA REGISTER"
3353                         " res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3354                 core_scsi3_put_pr_reg(pr_reg);
3355                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
3356         }
3357         /*
3358          * The service active reservation key needs to be non zero
3359          */
3360         if (!sa_res_key) {
3361                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3362                         " sa_res_key\n");
3363                 core_scsi3_put_pr_reg(pr_reg);
3364                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3365         }
3366
3367         /*
3368          * Determine the Relative Target Port Identifier where the reservation
3369          * will be moved to for the TransportID containing SCSI initiator WWN
3370          * information.
3371          */
3372         buf = transport_kmap_first_data_page(cmd);
3373         rtpi = (buf[18] & 0xff) << 8;
3374         rtpi |= buf[19] & 0xff;
3375         tid_len = (buf[20] & 0xff) << 24;
3376         tid_len |= (buf[21] & 0xff) << 16;
3377         tid_len |= (buf[22] & 0xff) << 8;
3378         tid_len |= buf[23] & 0xff;
3379         transport_kunmap_first_data_page(cmd);
3380         buf = NULL;
3381
3382         if ((tid_len + 24) != cmd->data_length) {
3383                 pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3384                         " does not equal CDB data_length: %u\n", tid_len,
3385                         cmd->data_length);
3386                 core_scsi3_put_pr_reg(pr_reg);
3387                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3388         }
3389
3390         spin_lock(&dev->se_port_lock);
3391         list_for_each_entry(se_port, &dev->dev_sep_list, sep_list) {
3392                 if (se_port->sep_rtpi != rtpi)
3393                         continue;
3394                 dest_se_tpg = se_port->sep_tpg;
3395                 if (!dest_se_tpg)
3396                         continue;
3397                 dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3398                 if (!dest_tf_ops)
3399                         continue;
3400
3401                 atomic_inc(&dest_se_tpg->tpg_pr_ref_count);
3402                 smp_mb__after_atomic_inc();
3403                 spin_unlock(&dev->se_port_lock);
3404
3405                 ret = core_scsi3_tpg_depend_item(dest_se_tpg);
3406                 if (ret != 0) {
3407                         pr_err("core_scsi3_tpg_depend_item() failed"
3408                                 " for dest_se_tpg\n");
3409                         atomic_dec(&dest_se_tpg->tpg_pr_ref_count);
3410                         smp_mb__after_atomic_dec();
3411                         core_scsi3_put_pr_reg(pr_reg);
3412                         return PYX_TRANSPORT_LU_COMM_FAILURE;
3413                 }
3414
3415                 spin_lock(&dev->se_port_lock);
3416                 break;
3417         }
3418         spin_unlock(&dev->se_port_lock);
3419
3420         if (!dest_se_tpg || !dest_tf_ops) {
3421                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3422                         " fabric ops from Relative Target Port Identifier:"
3423                         " %hu\n", rtpi);
3424                 core_scsi3_put_pr_reg(pr_reg);
3425                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3426         }
3427
3428         buf = transport_kmap_first_data_page(cmd);
3429         proto_ident = (buf[24] & 0x0f);
3430 #if 0
3431         pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3432                         " 0x%02x\n", proto_ident);
3433 #endif
3434         if (proto_ident != dest_tf_ops->get_fabric_proto_ident(dest_se_tpg)) {
3435                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3436                         " proto_ident: 0x%02x does not match ident: 0x%02x"
3437                         " from fabric: %s\n", proto_ident,
3438                         dest_tf_ops->get_fabric_proto_ident(dest_se_tpg),
3439                         dest_tf_ops->get_fabric_name());
3440                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3441                 goto out;
3442         }
3443         if (dest_tf_ops->tpg_parse_pr_out_transport_id == NULL) {
3444                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Fabric does not"
3445                         " containg a valid tpg_parse_pr_out_transport_id"
3446                         " function pointer\n");
3447                 ret = PYX_TRANSPORT_LU_COMM_FAILURE;
3448                 goto out;
3449         }
3450         initiator_str = dest_tf_ops->tpg_parse_pr_out_transport_id(dest_se_tpg,
3451                         (const char *)&buf[24], &tmp_tid_len, &iport_ptr);
3452         if (!initiator_str) {
3453                 pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3454                         " initiator_str from Transport ID\n");
3455                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3456                 goto out;
3457         }
3458
3459         transport_kunmap_first_data_page(cmd);
3460         buf = NULL;
3461
3462         pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3463                 " %s\n", dest_tf_ops->get_fabric_name(), (iport_ptr != NULL) ?
3464                 "port" : "device", initiator_str, (iport_ptr != NULL) ?
3465                 iport_ptr : "");
3466         /*
3467          * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3468          * action specifies a TransportID that is the same as the initiator port
3469          * of the I_T nexus for the command received, then the command shall
3470          * be terminated with CHECK CONDITION status, with the sense key set to
3471          * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3472          * IN PARAMETER LIST.
3473          */
3474         pr_reg_nacl = pr_reg->pr_reg_nacl;
3475         matching_iname = (!strcmp(initiator_str,
3476                                   pr_reg_nacl->initiatorname)) ? 1 : 0;
3477         if (!matching_iname)
3478                 goto after_iport_check;
3479
3480         if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3481                 pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3482                         " matches: %s on received I_T Nexus\n", initiator_str,
3483                         pr_reg_nacl->initiatorname);
3484                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3485                 goto out;
3486         }
3487         if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3488                 pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3489                         " matches: %s %s on received I_T Nexus\n",
3490                         initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3491                         pr_reg->pr_reg_isid);
3492                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3493                 goto out;
3494         }
3495 after_iport_check:
3496         /*
3497          * Locate the destination struct se_node_acl from the received Transport ID
3498          */
3499         spin_lock_bh(&dest_se_tpg->acl_node_lock);
3500         dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3501                                 initiator_str);
3502         if (dest_node_acl) {
3503                 atomic_inc(&dest_node_acl->acl_pr_ref_count);
3504                 smp_mb__after_atomic_inc();
3505         }
3506         spin_unlock_bh(&dest_se_tpg->acl_node_lock);
3507
3508         if (!dest_node_acl) {
3509                 pr_err("Unable to locate %s dest_node_acl for"
3510                         " TransportID%s\n", dest_tf_ops->get_fabric_name(),
3511                         initiator_str);
3512                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3513                 goto out;
3514         }
3515         ret = core_scsi3_nodeacl_depend_item(dest_node_acl);
3516         if (ret != 0) {
3517                 pr_err("core_scsi3_nodeacl_depend_item() for"
3518                         " dest_node_acl\n");
3519                 atomic_dec(&dest_node_acl->acl_pr_ref_count);
3520                 smp_mb__after_atomic_dec();
3521                 dest_node_acl = NULL;
3522                 ret = PYX_TRANSPORT_LU_COMM_FAILURE;
3523                 goto out;
3524         }
3525 #if 0
3526         pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3527                 " %s from TransportID\n", dest_tf_ops->get_fabric_name(),
3528                 dest_node_acl->initiatorname);
3529 #endif
3530         /*
3531          * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3532          * PORT IDENTIFIER.
3533          */
3534         dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3535         if (!dest_se_deve) {
3536                 pr_err("Unable to locate %s dest_se_deve from RTPI:"
3537                         " %hu\n",  dest_tf_ops->get_fabric_name(), rtpi);
3538                 ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3539                 goto out;
3540         }
3541
3542         ret = core_scsi3_lunacl_depend_item(dest_se_deve);
3543         if (ret < 0) {
3544                 pr_err("core_scsi3_lunacl_depend_item() failed\n");
3545                 atomic_dec(&dest_se_deve->pr_ref_count);
3546                 smp_mb__after_atomic_dec();
3547                 dest_se_deve = NULL;
3548                 ret = PYX_TRANSPORT_LU_COMM_FAILURE;
3549                 goto out;
3550         }
3551 #if 0
3552         pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3553                 " ACL for dest_se_deve->mapped_lun: %u\n",
3554                 dest_tf_ops->get_fabric_name(), dest_node_acl->initiatorname,
3555                 dest_se_deve->mapped_lun);
3556 #endif
3557         /*
3558          * A persistent reservation needs to already existing in order to
3559          * successfully complete the REGISTER_AND_MOVE service action..
3560          */
3561         spin_lock(&dev->dev_reservation_lock);
3562         pr_res_holder = dev->dev_pr_res_holder;
3563         if (!pr_res_holder) {
3564                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3565                         " currently held\n");
3566                 spin_unlock(&dev->dev_reservation_lock);
3567                 ret = PYX_TRANSPORT_INVALID_CDB_FIELD;
3568                 goto out;
3569         }
3570         /*
3571          * The received on I_T Nexus must be the reservation holder.
3572          *
3573          * From spc4r17 section 5.7.8  Table 50 --
3574          *      Register behaviors for a REGISTER AND MOVE service action
3575          */
3576         if (pr_res_holder != pr_reg) {
3577                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3578                         " Nexus is not reservation holder\n");
3579                 spin_unlock(&dev->dev_reservation_lock);
3580                 ret = PYX_TRANSPORT_RESERVATION_CONFLICT;
3581                 goto out;
3582         }
3583         /*
3584          * From spc4r17 section 5.7.8: registering and moving reservation
3585          *
3586          * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3587          * action is received and the established persistent reservation is a
3588          * Write Exclusive - All Registrants type or Exclusive Access -
3589          * All Registrants type reservation, then the command shall be completed
3590          * with RESERVATION CONFLICT status.
3591          */
3592         if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3593             (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3594                 pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3595                         " reservation for type: %s\n",
3596                         core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3597                 spin_unlock(&dev->dev_reservation_lock);
3598                 ret = PYX_TRANSPORT_RESERVATION_CONFLICT;
3599                 goto out;
3600         }
3601         pr_res_nacl = pr_res_holder->pr_reg_nacl;
3602         /*
3603          * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3604          */
3605         type = pr_res_holder->pr_res_type;
3606         scope = pr_res_holder->pr_res_type;
3607         /*
3608          * c) Associate the reservation key specified in the SERVICE ACTION
3609          *    RESERVATION KEY field with the I_T nexus specified as the
3610          *    destination of the register and move, where:
3611          *    A) The I_T nexus is specified by the TransportID and the
3612          *       RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3613          *    B) Regardless of the TransportID format used, the association for
3614          *       the initiator port is based on either the initiator port name
3615          *       (see 3.1.71) on SCSI transport protocols where port names are
3616          *       required or the initiator port identifier (see 3.1.70) on SCSI
3617          *       transport protocols where port names are not required;
3618          * d) Register the reservation key specified in the SERVICE ACTION
3619          *    RESERVATION KEY field;
3620          * e) Retain the reservation key specified in the SERVICE ACTION
3621          *    RESERVATION KEY field and associated information;
3622          *
3623          * Also, It is not an error for a REGISTER AND MOVE service action to
3624          * register an I_T nexus that is already registered with the same
3625          * reservation key or a different reservation key.
3626          */
3627         dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3628                                         iport_ptr);
3629         if (!dest_pr_reg) {
3630                 ret = core_scsi3_alloc_registration(cmd->se_dev,
3631                                 dest_node_acl, dest_se_deve, iport_ptr,
3632                                 sa_res_key, 0, aptpl, 2, 1);
3633                 if (ret != 0) {
3634                         spin_unlock(&dev->dev_reservation_lock);
3635                         ret = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3636                         goto out;
3637                 }
3638                 dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3639                                                 iport_ptr);
3640                 new_reg = 1;
3641         }
3642         /*
3643          * f) Release the persistent reservation for the persistent reservation
3644          *    holder (i.e., the I_T nexus on which the
3645          */
3646         __core_scsi3_complete_pro_release(dev, pr_res_nacl,
3647                         dev->dev_pr_res_holder, 0);
3648         /*
3649          * g) Move the persistent reservation to the specified I_T nexus using
3650          *    the same scope and type as the persistent reservation released in
3651          *    item f); and
3652          */
3653         dev->dev_pr_res_holder = dest_pr_reg;
3654         dest_pr_reg->pr_res_holder = 1;
3655         dest_pr_reg->pr_res_type = type;
3656         pr_reg->pr_res_scope = scope;
3657         prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
3658                                 PR_REG_ISID_ID_LEN);
3659         /*
3660          * Increment PRGeneration for existing registrations..
3661          */
3662         if (!new_reg)
3663                 dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3664         spin_unlock(&dev->dev_reservation_lock);
3665
3666         pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3667                 " created new reservation holder TYPE: %s on object RTPI:"
3668                 " %hu  PRGeneration: 0x%08x\n", dest_tf_ops->get_fabric_name(),
3669                 core_scsi3_pr_dump_type(type), rtpi,
3670                 dest_pr_reg->pr_res_generation);
3671         pr_debug("SPC-3 PR Successfully moved reservation from"
3672                 " %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3673                 tf_ops->get_fabric_name(), pr_reg_nacl->initiatorname,
3674                 (prf_isid) ? &i_buf[0] : "", dest_tf_ops->get_fabric_name(),
3675                 dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3676                 iport_ptr : "");
3677         /*
3678          * It is now safe to release configfs group dependencies for destination
3679          * of Transport ID Initiator Device/Port Identifier
3680          */
3681         core_scsi3_lunacl_undepend_item(dest_se_deve);
3682         core_scsi3_nodeacl_undepend_item(dest_node_acl);
3683         core_scsi3_tpg_undepend_item(dest_se_tpg);
3684         /*
3685          * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3686          * nexus on which PERSISTENT RESERVE OUT command was received.
3687          */
3688         if (unreg) {
3689                 spin_lock(&pr_tmpl->registration_lock);
3690                 __core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3691                 spin_unlock(&pr_tmpl->registration_lock);
3692         } else
3693                 core_scsi3_put_pr_reg(pr_reg);
3694
3695         /*
3696          * Clear the APTPL metadata if APTPL has been disabled, otherwise
3697          * write out the updated metadata to struct file for this SCSI device.
3698          */
3699         if (!aptpl) {
3700                 pr_tmpl->pr_aptpl_active = 0;
3701                 core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
3702                 pr_debug("SPC-3 PR: Set APTPL Bit Deactivated for"
3703                                 " REGISTER_AND_MOVE\n");
3704         } else {
3705                 pr_tmpl->pr_aptpl_active = 1;
3706                 ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3707                                 &dest_pr_reg->pr_aptpl_buf[0],
3708                                 pr_tmpl->pr_aptpl_buf_len);
3709                 if (!ret)
3710                         pr_debug("SPC-3 PR: Set APTPL Bit Activated for"
3711                                         " REGISTER_AND_MOVE\n");
3712         }
3713
3714         transport_kunmap_first_data_page(cmd);
3715
3716         core_scsi3_put_pr_reg(dest_pr_reg);
3717         return 0;
3718 out:
3719         if (buf)
3720                 transport_kunmap_first_data_page(cmd);
3721         if (dest_se_deve)
3722                 core_scsi3_lunacl_undepend_item(dest_se_deve);
3723         if (dest_node_acl)
3724                 core_scsi3_nodeacl_undepend_item(dest_node_acl);
3725         core_scsi3_tpg_undepend_item(dest_se_tpg);
3726         core_scsi3_put_pr_reg(pr_reg);
3727         return ret;
3728 }
3729
3730 static unsigned long long core_scsi3_extract_reservation_key(unsigned char *cdb)
3731 {
3732         unsigned int __v1, __v2;
3733
3734         __v1 = (cdb[0] << 24) | (cdb[1] << 16) | (cdb[2] << 8) | cdb[3];
3735         __v2 = (cdb[4] << 24) | (cdb[5] << 16) | (cdb[6] << 8) | cdb[7];
3736
3737         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
3738 }
3739
3740 /*
3741  * See spc4r17 section 6.14 Table 170
3742  */
3743 static int core_scsi3_emulate_pr_out(struct se_cmd *cmd, unsigned char *cdb)
3744 {
3745         unsigned char *buf;
3746         u64 res_key, sa_res_key;
3747         int sa, scope, type, aptpl;
3748         int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3749         /*
3750          * FIXME: A NULL struct se_session pointer means an this is not coming from
3751          * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3752          */
3753         if (!cmd->se_sess)
3754                 return PYX_TRANSPORT_LU_COMM_FAILURE;
3755
3756         if (cmd->data_length < 24) {
3757                 pr_warn("SPC-PR: Received PR OUT parameter list"
3758                         " length too small: %u\n", cmd->data_length);
3759                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3760         }
3761         /*
3762          * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3763          */
3764         sa = (cdb[1] & 0x1f);
3765         scope = (cdb[2] & 0xf0);
3766         type = (cdb[2] & 0x0f);
3767
3768         buf = transport_kmap_first_data_page(cmd);
3769         /*
3770          * From PERSISTENT_RESERVE_OUT parameter list (payload)
3771          */
3772         res_key = core_scsi3_extract_reservation_key(&buf[0]);
3773         sa_res_key = core_scsi3_extract_reservation_key(&buf[8]);
3774         /*
3775          * REGISTER_AND_MOVE uses a different SA parameter list containing
3776          * SCSI TransportIDs.
3777          */
3778         if (sa != PRO_REGISTER_AND_MOVE) {
3779                 spec_i_pt = (buf[20] & 0x08);
3780                 all_tg_pt = (buf[20] & 0x04);
3781                 aptpl = (buf[20] & 0x01);
3782         } else {
3783                 aptpl = (buf[17] & 0x01);
3784                 unreg = (buf[17] & 0x02);
3785         }
3786         transport_kunmap_first_data_page(cmd);
3787         buf = NULL;
3788
3789         /*
3790          * SPEC_I_PT=1 is only valid for Service action: REGISTER
3791          */
3792         if (spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER))
3793                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3794         /*
3795          * From spc4r17 section 6.14:
3796          *
3797          * If the SPEC_I_PT bit is set to zero, the service action is not
3798          * REGISTER AND MOVE, and the parameter list length is not 24, then
3799          * the command shall be terminated with CHECK CONDITION status, with
3800          * the sense key set to ILLEGAL REQUEST, and the additional sense
3801          * code set to PARAMETER LIST LENGTH ERROR.
3802          */
3803         if (!spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER_AND_MOVE) &&
3804             (cmd->data_length != 24)) {
3805                 pr_warn("SPC-PR: Received PR OUT illegal parameter"
3806                         " list length: %u\n", cmd->data_length);
3807                 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
3808         }
3809         /*
3810          * (core_scsi3_emulate_pro_* function parameters
3811          * are defined by spc4r17 Table 174:
3812          * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3813          */
3814         switch (sa) {
3815         case PRO_REGISTER:
3816                 return core_scsi3_emulate_pro_register(cmd,
3817                         res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, 0);
3818         case PRO_RESERVE:
3819                 return core_scsi3_emulate_pro_reserve(cmd,
3820                         type, scope, res_key);
3821         case PRO_RELEASE:
3822                 return core_scsi3_emulate_pro_release(cmd,
3823                         type, scope, res_key);
3824         case PRO_CLEAR:
3825                 return core_scsi3_emulate_pro_clear(cmd, res_key);
3826         case PRO_PREEMPT:
3827                 return core_scsi3_emulate_pro_preempt(cmd, type, scope,
3828                                         res_key, sa_res_key, 0);
3829         case PRO_PREEMPT_AND_ABORT:
3830                 return core_scsi3_emulate_pro_preempt(cmd, type, scope,
3831                                         res_key, sa_res_key, 1);
3832         case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3833                 return core_scsi3_emulate_pro_register(cmd,
3834                         0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, 1);
3835         case PRO_REGISTER_AND_MOVE:
3836                 return core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3837                                 sa_res_key, aptpl, unreg);
3838         default:
3839                 pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3840                         " action: 0x%02x\n", cdb[1] & 0x1f);
3841                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
3842         }
3843
3844         return PYX_TRANSPORT_INVALID_CDB_FIELD;
3845 }
3846
3847 /*
3848  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3849  *
3850  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3851  */
3852 static int core_scsi3_pri_read_keys(struct se_cmd *cmd)
3853 {
3854         struct se_device *se_dev = cmd->se_dev;
3855         struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
3856         struct t10_pr_registration *pr_reg;
3857         unsigned char *buf;
3858         u32 add_len = 0, off = 8;
3859
3860         if (cmd->data_length < 8) {
3861                 pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3862                         " too small\n", cmd->data_length);
3863                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
3864         }
3865
3866         buf = transport_kmap_first_data_page(cmd);
3867         buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
3868         buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
3869         buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
3870         buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
3871
3872         spin_lock(&su_dev->t10_pr.registration_lock);
3873         list_for_each_entry(pr_reg, &su_dev->t10_pr.registration_list,
3874                         pr_reg_list) {
3875                 /*
3876                  * Check for overflow of 8byte PRI READ_KEYS payload and
3877                  * next reservation key list descriptor.
3878                  */
3879                 if ((add_len + 8) > (cmd->data_length - 8))
3880                         break;
3881
3882                 buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3883                 buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3884                 buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3885                 buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3886                 buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3887                 buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3888                 buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3889                 buf[off++] = (pr_reg->pr_res_key & 0xff);
3890
3891                 add_len += 8;
3892         }
3893         spin_unlock(&su_dev->t10_pr.registration_lock);
3894
3895         buf[4] = ((add_len >> 24) & 0xff);
3896         buf[5] = ((add_len >> 16) & 0xff);
3897         buf[6] = ((add_len >> 8) & 0xff);
3898         buf[7] = (add_len & 0xff);
3899
3900         transport_kunmap_first_data_page(cmd);
3901
3902         return 0;
3903 }
3904
3905 /*
3906  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3907  *
3908  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3909  */
3910 static int core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3911 {
3912         struct se_device *se_dev = cmd->se_dev;
3913         struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
3914         struct t10_pr_registration *pr_reg;
3915         unsigned char *buf;
3916         u64 pr_res_key;
3917         u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
3918
3919         if (cmd->data_length < 8) {
3920                 pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3921                         " too small\n", cmd->data_length);
3922                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
3923         }
3924
3925         buf = transport_kmap_first_data_page(cmd);
3926         buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
3927         buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
3928         buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
3929         buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
3930
3931         spin_lock(&se_dev->dev_reservation_lock);
3932         pr_reg = se_dev->dev_pr_res_holder;
3933         if ((pr_reg)) {
3934                 /*
3935                  * Set the hardcoded Additional Length
3936                  */
3937                 buf[4] = ((add_len >> 24) & 0xff);
3938                 buf[5] = ((add_len >> 16) & 0xff);
3939                 buf[6] = ((add_len >> 8) & 0xff);
3940                 buf[7] = (add_len & 0xff);
3941
3942                 if (cmd->data_length < 22)
3943                         goto err;
3944
3945                 /*
3946                  * Set the Reservation key.
3947                  *
3948                  * From spc4r17, section 5.7.10:
3949                  * A persistent reservation holder has its reservation key
3950                  * returned in the parameter data from a PERSISTENT
3951                  * RESERVE IN command with READ RESERVATION service action as
3952                  * follows:
3953                  * a) For a persistent reservation of the type Write Exclusive
3954                  *    - All Registrants or Exclusive Access Â­ All Regitrants,
3955                  *      the reservation key shall be set to zero; or
3956                  * b) For all other persistent reservation types, the
3957                  *    reservation key shall be set to the registered
3958                  *    reservation key for the I_T nexus that holds the
3959                  *    persistent reservation.
3960                  */
3961                 if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3962                     (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3963                         pr_res_key = 0;
3964                 else
3965                         pr_res_key = pr_reg->pr_res_key;
3966
3967                 buf[8] = ((pr_res_key >> 56) & 0xff);
3968                 buf[9] = ((pr_res_key >> 48) & 0xff);
3969                 buf[10] = ((pr_res_key >> 40) & 0xff);
3970                 buf[11] = ((pr_res_key >> 32) & 0xff);
3971                 buf[12] = ((pr_res_key >> 24) & 0xff);
3972                 buf[13] = ((pr_res_key >> 16) & 0xff);
3973                 buf[14] = ((pr_res_key >> 8) & 0xff);
3974                 buf[15] = (pr_res_key & 0xff);
3975                 /*
3976                  * Set the SCOPE and TYPE
3977                  */
3978                 buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3979                           (pr_reg->pr_res_type & 0x0f);
3980         }
3981
3982 err:
3983         spin_unlock(&se_dev->dev_reservation_lock);
3984         transport_kunmap_first_data_page(cmd);
3985
3986         return 0;
3987 }
3988
3989 /*
3990  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3991  *
3992  * See spc4r17 section 6.13.4 Table 165
3993  */
3994 static int core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3995 {
3996         struct se_device *dev = cmd->se_dev;
3997         struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
3998         unsigned char *buf;
3999         u16 add_len = 8; /* Hardcoded to 8. */
4000
4001         if (cmd->data_length < 6) {
4002                 pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
4003                         " %u too small\n", cmd->data_length);
4004                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
4005         }
4006
4007         buf = transport_kmap_first_data_page(cmd);
4008
4009         buf[0] = ((add_len << 8) & 0xff);
4010         buf[1] = (add_len & 0xff);
4011         buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
4012         buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
4013         buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
4014         buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
4015         /*
4016          * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
4017          * set the TMV: Task Mask Valid bit.
4018          */
4019         buf[3] |= 0x80;
4020         /*
4021          * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
4022          */
4023         buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
4024         /*
4025          * PTPL_A: Persistence across Target Power Loss Active bit
4026          */
4027         if (pr_tmpl->pr_aptpl_active)
4028                 buf[3] |= 0x01;
4029         /*
4030          * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
4031          */
4032         buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
4033         buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
4034         buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
4035         buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
4036         buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
4037         buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
4038
4039         transport_kunmap_first_data_page(cmd);
4040
4041         return 0;
4042 }
4043
4044 /*
4045  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
4046  *
4047  * See spc4r17 section 6.13.5 Table 168 and 169
4048  */
4049 static int core_scsi3_pri_read_full_status(struct se_cmd *cmd)
4050 {
4051         struct se_device *se_dev = cmd->se_dev;
4052         struct se_node_acl *se_nacl;
4053         struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
4054         struct se_portal_group *se_tpg;
4055         struct t10_pr_registration *pr_reg, *pr_reg_tmp;
4056         struct t10_reservation *pr_tmpl = &se_dev->se_sub_dev->t10_pr;
4057         unsigned char *buf;
4058         u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
4059         u32 off = 8; /* off into first Full Status descriptor */
4060         int format_code = 0;
4061
4062         if (cmd->data_length < 8) {
4063                 pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
4064                         " too small\n", cmd->data_length);
4065                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
4066         }
4067
4068         buf = transport_kmap_first_data_page(cmd);
4069
4070         buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
4071         buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
4072         buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
4073         buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
4074
4075         spin_lock(&pr_tmpl->registration_lock);
4076         list_for_each_entry_safe(pr_reg, pr_reg_tmp,
4077                         &pr_tmpl->registration_list, pr_reg_list) {
4078
4079                 se_nacl = pr_reg->pr_reg_nacl;
4080                 se_tpg = pr_reg->pr_reg_nacl->se_tpg;
4081                 add_desc_len = 0;
4082
4083                 atomic_inc(&pr_reg->pr_res_holders);
4084                 smp_mb__after_atomic_inc();
4085                 spin_unlock(&pr_tmpl->registration_lock);
4086                 /*
4087                  * Determine expected length of $FABRIC_MOD specific
4088                  * TransportID full status descriptor..
4089                  */
4090                 exp_desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id_len(
4091                                 se_tpg, se_nacl, pr_reg, &format_code);
4092
4093                 if ((exp_desc_len + add_len) > cmd->data_length) {
4094                         pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
4095                                 " out of buffer: %d\n", cmd->data_length);
4096                         spin_lock(&pr_tmpl->registration_lock);
4097                         atomic_dec(&pr_reg->pr_res_holders);
4098                         smp_mb__after_atomic_dec();
4099                         break;
4100                 }
4101                 /*
4102                  * Set RESERVATION KEY
4103                  */
4104                 buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
4105                 buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
4106                 buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
4107                 buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
4108                 buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
4109                 buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
4110                 buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
4111                 buf[off++] = (pr_reg->pr_res_key & 0xff);
4112                 off += 4; /* Skip Over Reserved area */
4113
4114                 /*
4115                  * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
4116                  */
4117                 if (pr_reg->pr_reg_all_tg_pt)
4118                         buf[off] = 0x02;
4119                 /*
4120                  * The struct se_lun pointer will be present for the
4121                  * reservation holder for PR_HOLDER bit.
4122                  *
4123                  * Also, if this registration is the reservation
4124                  * holder, fill in SCOPE and TYPE in the next byte.
4125                  */
4126                 if (pr_reg->pr_res_holder) {
4127                         buf[off++] |= 0x01;
4128                         buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
4129                                      (pr_reg->pr_res_type & 0x0f);
4130                 } else
4131                         off += 2;
4132
4133                 off += 4; /* Skip over reserved area */
4134                 /*
4135                  * From spc4r17 6.3.15:
4136                  *
4137                  * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
4138                  * IDENTIFIER field contains the relative port identifier (see
4139                  * 3.1.120) of the target port that is part of the I_T nexus
4140                  * described by this full status descriptor. If the ALL_TG_PT
4141                  * bit is set to one, the contents of the RELATIVE TARGET PORT
4142                  * IDENTIFIER field are not defined by this standard.
4143                  */
4144                 if (!pr_reg->pr_reg_all_tg_pt) {
4145                         struct se_port *port = pr_reg->pr_reg_tg_pt_lun->lun_sep;
4146
4147                         buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
4148                         buf[off++] = (port->sep_rtpi & 0xff);
4149                 } else
4150                         off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFER */
4151
4152                 /*
4153                  * Now, have the $FABRIC_MOD fill in the protocol identifier
4154                  */
4155                 desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id(se_tpg,
4156                                 se_nacl, pr_reg, &format_code, &buf[off+4]);
4157
4158                 spin_lock(&pr_tmpl->registration_lock);
4159                 atomic_dec(&pr_reg->pr_res_holders);
4160                 smp_mb__after_atomic_dec();
4161                 /*
4162                  * Set the ADDITIONAL DESCRIPTOR LENGTH
4163                  */
4164                 buf[off++] = ((desc_len >> 24) & 0xff);
4165                 buf[off++] = ((desc_len >> 16) & 0xff);
4166                 buf[off++] = ((desc_len >> 8) & 0xff);
4167                 buf[off++] = (desc_len & 0xff);
4168                 /*
4169                  * Size of full desctipor header minus TransportID
4170                  * containing $FABRIC_MOD specific) initiator device/port
4171                  * WWN information.
4172                  *
4173                  *  See spc4r17 Section 6.13.5 Table 169
4174                  */
4175                 add_desc_len = (24 + desc_len);
4176
4177                 off += desc_len;
4178                 add_len += add_desc_len;
4179         }
4180         spin_unlock(&pr_tmpl->registration_lock);
4181         /*
4182          * Set ADDITIONAL_LENGTH
4183          */
4184         buf[4] = ((add_len >> 24) & 0xff);
4185         buf[5] = ((add_len >> 16) & 0xff);
4186         buf[6] = ((add_len >> 8) & 0xff);
4187         buf[7] = (add_len & 0xff);
4188
4189         transport_kunmap_first_data_page(cmd);
4190
4191         return 0;
4192 }
4193
4194 static int core_scsi3_emulate_pr_in(struct se_cmd *cmd, unsigned char *cdb)
4195 {
4196         switch (cdb[1] & 0x1f) {
4197         case PRI_READ_KEYS:
4198                 return core_scsi3_pri_read_keys(cmd);
4199         case PRI_READ_RESERVATION:
4200                 return core_scsi3_pri_read_reservation(cmd);
4201         case PRI_REPORT_CAPABILITIES:
4202                 return core_scsi3_pri_report_capabilities(cmd);
4203         case PRI_READ_FULL_STATUS:
4204                 return core_scsi3_pri_read_full_status(cmd);
4205         default:
4206                 pr_err("Unknown PERSISTENT_RESERVE_IN service"
4207                         " action: 0x%02x\n", cdb[1] & 0x1f);
4208                 return PYX_TRANSPORT_INVALID_CDB_FIELD;
4209         }
4210
4211 }
4212
4213 int core_scsi3_emulate_pr(struct se_cmd *cmd)
4214 {
4215         unsigned char *cdb = &cmd->t_task_cdb[0];
4216         struct se_device *dev = cmd->se_dev;
4217         /*
4218          * Following spc2r20 5.5.1 Reservations overview:
4219          *
4220          * If a logical unit has been reserved by any RESERVE command and is
4221          * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4222          * PERSISTENT RESERVE OUT commands shall conflict regardless of
4223          * initiator or service action and shall terminate with a RESERVATION
4224          * CONFLICT status.
4225          */
4226         if (dev->dev_flags & DF_SPC2_RESERVATIONS) {
4227                 pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4228                         " SPC-2 reservation is held, returning"
4229                         " RESERVATION_CONFLICT\n");
4230                 return PYX_TRANSPORT_RESERVATION_CONFLICT;
4231         }
4232
4233         return (cdb[0] == PERSISTENT_RESERVE_OUT) ?
4234                core_scsi3_emulate_pr_out(cmd, cdb) :
4235                core_scsi3_emulate_pr_in(cmd, cdb);
4236 }
4237
4238 static int core_pt_reservation_check(struct se_cmd *cmd, u32 *pr_res_type)
4239 {
4240         return 0;
4241 }
4242
4243 static int core_pt_seq_non_holder(
4244         struct se_cmd *cmd,
4245         unsigned char *cdb,
4246         u32 pr_reg_type)
4247 {
4248         return 0;
4249 }
4250
4251 int core_setup_reservations(struct se_device *dev, int force_pt)
4252 {
4253         struct se_subsystem_dev *su_dev = dev->se_sub_dev;
4254         struct t10_reservation *rest = &su_dev->t10_pr;
4255         /*
4256          * If this device is from Target_Core_Mod/pSCSI, use the reservations
4257          * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
4258          * cause a problem because libata and some SATA RAID HBAs appear
4259          * under Linux/SCSI, but to emulate reservations themselves.
4260          */
4261         if (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
4262             !(dev->se_sub_dev->se_dev_attrib.emulate_reservations)) || force_pt) {
4263                 rest->res_type = SPC_PASSTHROUGH;
4264                 rest->pr_ops.t10_reservation_check = &core_pt_reservation_check;
4265                 rest->pr_ops.t10_seq_non_holder = &core_pt_seq_non_holder;
4266                 pr_debug("%s: Using SPC_PASSTHROUGH, no reservation"
4267                         " emulation\n", dev->transport->name);
4268                 return 0;
4269         }
4270         /*
4271          * If SPC-3 or above is reported by real or emulated struct se_device,
4272          * use emulated Persistent Reservations.
4273          */
4274         if (dev->transport->get_device_rev(dev) >= SCSI_3) {
4275                 rest->res_type = SPC3_PERSISTENT_RESERVATIONS;
4276                 rest->pr_ops.t10_reservation_check = &core_scsi3_pr_reservation_check;
4277                 rest->pr_ops.t10_seq_non_holder = &core_scsi3_pr_seq_non_holder;
4278                 pr_debug("%s: Using SPC3_PERSISTENT_RESERVATIONS"
4279                         " emulation\n", dev->transport->name);
4280         } else {
4281                 rest->res_type = SPC2_RESERVATIONS;
4282                 rest->pr_ops.t10_reservation_check = &core_scsi2_reservation_check;
4283                 rest->pr_ops.t10_seq_non_holder =
4284                                 &core_scsi2_reservation_seq_non_holder;
4285                 pr_debug("%s: Using SPC2_RESERVATIONS emulation\n",
4286                         dev->transport->name);
4287         }
4288
4289         return 0;
4290 }