xref: /linux/drivers/target/target_core_pr.c (revision 97f0b13452198290799fd6780f05fbaa74f927d3)
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  * (c) Copyright 2009-2013 Datera, Inc.
8  *
9  * Nicholas A. Bellinger <nab@kernel.org>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24  *
25  ******************************************************************************/
26 
27 #include <linux/slab.h>
28 #include <linux/spinlock.h>
29 #include <linux/list.h>
30 #include <linux/file.h>
31 #include <scsi/scsi_proto.h>
32 #include <asm/unaligned.h>
33 
34 #include <target/target_core_base.h>
35 #include <target/target_core_backend.h>
36 #include <target/target_core_fabric.h>
37 #include <target/target_core_configfs.h>
38 
39 #include "target_core_internal.h"
40 #include "target_core_pr.h"
41 #include "target_core_ua.h"
42 
43 /*
44  * Used for Specify Initiator Ports Capable Bit (SPEC_I_PT)
45  */
46 struct pr_transport_id_holder {
47 	int dest_local_nexus;
48 	struct t10_pr_registration *dest_pr_reg;
49 	struct se_portal_group *dest_tpg;
50 	struct se_node_acl *dest_node_acl;
51 	struct se_dev_entry *dest_se_deve;
52 	struct list_head dest_list;
53 };
54 
55 void core_pr_dump_initiator_port(
56 	struct t10_pr_registration *pr_reg,
57 	char *buf,
58 	u32 size)
59 {
60 	if (!pr_reg->isid_present_at_reg)
61 		buf[0] = '\0';
62 
63 	snprintf(buf, size, ",i,0x%s", pr_reg->pr_reg_isid);
64 }
65 
66 enum register_type {
67 	REGISTER,
68 	REGISTER_AND_IGNORE_EXISTING_KEY,
69 	REGISTER_AND_MOVE,
70 };
71 
72 enum preempt_type {
73 	PREEMPT,
74 	PREEMPT_AND_ABORT,
75 };
76 
77 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
78 					      struct t10_pr_registration *, int, int);
79 
80 static int is_reservation_holder(
81 	struct t10_pr_registration *pr_res_holder,
82 	struct t10_pr_registration *pr_reg)
83 {
84 	int pr_res_type;
85 
86 	if (pr_res_holder) {
87 		pr_res_type = pr_res_holder->pr_res_type;
88 
89 		return pr_res_holder == pr_reg ||
90 		       pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
91 		       pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG;
92 	}
93 	return 0;
94 }
95 
96 static sense_reason_t
97 target_scsi2_reservation_check(struct se_cmd *cmd)
98 {
99 	struct se_device *dev = cmd->se_dev;
100 	struct se_session *sess = cmd->se_sess;
101 
102 	switch (cmd->t_task_cdb[0]) {
103 	case INQUIRY:
104 	case RELEASE:
105 	case RELEASE_10:
106 		return 0;
107 	default:
108 		break;
109 	}
110 
111 	if (!dev->dev_reserved_node_acl || !sess)
112 		return 0;
113 
114 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
115 		return TCM_RESERVATION_CONFLICT;
116 
117 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
118 		if (dev->dev_res_bin_isid != sess->sess_bin_isid)
119 			return TCM_RESERVATION_CONFLICT;
120 	}
121 
122 	return 0;
123 }
124 
125 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
126 					struct se_node_acl *, struct se_session *);
127 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
128 
129 static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
130 {
131 	struct se_session *se_sess = cmd->se_sess;
132 	struct se_device *dev = cmd->se_dev;
133 	struct t10_pr_registration *pr_reg;
134 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
135 	int conflict = 0;
136 
137 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
138 			se_sess);
139 	if (pr_reg) {
140 		/*
141 		 * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
142 		 * behavior
143 		 *
144 		 * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
145 		 * status, but no reservation shall be established and the
146 		 * persistent reservation shall not be changed, if the command
147 		 * is received from a) and b) below.
148 		 *
149 		 * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
150 		 * status, but the persistent reservation shall not be released,
151 		 * if the command is received from a) and b)
152 		 *
153 		 * a) An I_T nexus that is a persistent reservation holder; or
154 		 * b) An I_T nexus that is registered if a registrants only or
155 		 *    all registrants type persistent reservation is present.
156 		 *
157 		 * In all other cases, a RESERVE(6) command, RESERVE(10) command,
158 		 * RELEASE(6) command, or RELEASE(10) command shall be processed
159 		 * as defined in SPC-2.
160 		 */
161 		if (pr_reg->pr_res_holder) {
162 			core_scsi3_put_pr_reg(pr_reg);
163 			return 1;
164 		}
165 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
166 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
167 		    (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
168 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
169 			core_scsi3_put_pr_reg(pr_reg);
170 			return 1;
171 		}
172 		core_scsi3_put_pr_reg(pr_reg);
173 		conflict = 1;
174 	} else {
175 		/*
176 		 * Following spc2r20 5.5.1 Reservations overview:
177 		 *
178 		 * If a logical unit has executed a PERSISTENT RESERVE OUT
179 		 * command with the REGISTER or the REGISTER AND IGNORE
180 		 * EXISTING KEY service action and is still registered by any
181 		 * initiator, all RESERVE commands and all RELEASE commands
182 		 * regardless of initiator shall conflict and shall terminate
183 		 * with a RESERVATION CONFLICT status.
184 		 */
185 		spin_lock(&pr_tmpl->registration_lock);
186 		conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
187 		spin_unlock(&pr_tmpl->registration_lock);
188 	}
189 
190 	if (conflict) {
191 		pr_err("Received legacy SPC-2 RESERVE/RELEASE"
192 			" while active SPC-3 registrations exist,"
193 			" returning RESERVATION_CONFLICT\n");
194 		return -EBUSY;
195 	}
196 
197 	return 0;
198 }
199 
200 sense_reason_t
201 target_scsi2_reservation_release(struct se_cmd *cmd)
202 {
203 	struct se_device *dev = cmd->se_dev;
204 	struct se_session *sess = cmd->se_sess;
205 	struct se_portal_group *tpg;
206 	int rc;
207 
208 	if (!sess || !sess->se_tpg)
209 		goto out;
210 	rc = target_check_scsi2_reservation_conflict(cmd);
211 	if (rc == 1)
212 		goto out;
213 	if (rc < 0)
214 		return TCM_RESERVATION_CONFLICT;
215 
216 	spin_lock(&dev->dev_reservation_lock);
217 	if (!dev->dev_reserved_node_acl || !sess)
218 		goto out_unlock;
219 
220 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
221 		goto out_unlock;
222 
223 	if (dev->dev_res_bin_isid != sess->sess_bin_isid)
224 		goto out_unlock;
225 
226 	dev->dev_reserved_node_acl = NULL;
227 	dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
228 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
229 		dev->dev_res_bin_isid = 0;
230 		dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS_WITH_ISID;
231 	}
232 	tpg = sess->se_tpg;
233 	pr_debug("SCSI-2 Released reservation for %s LUN: %u ->"
234 		" MAPPED LUN: %u for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
235 		cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
236 		sess->se_node_acl->initiatorname);
237 
238 out_unlock:
239 	spin_unlock(&dev->dev_reservation_lock);
240 out:
241 	target_complete_cmd(cmd, GOOD);
242 	return 0;
243 }
244 
245 sense_reason_t
246 target_scsi2_reservation_reserve(struct se_cmd *cmd)
247 {
248 	struct se_device *dev = cmd->se_dev;
249 	struct se_session *sess = cmd->se_sess;
250 	struct se_portal_group *tpg;
251 	sense_reason_t ret = 0;
252 	int rc;
253 
254 	if ((cmd->t_task_cdb[1] & 0x01) &&
255 	    (cmd->t_task_cdb[1] & 0x02)) {
256 		pr_err("LongIO and Obselete Bits set, returning"
257 				" ILLEGAL_REQUEST\n");
258 		return TCM_UNSUPPORTED_SCSI_OPCODE;
259 	}
260 	/*
261 	 * This is currently the case for target_core_mod passthrough struct se_cmd
262 	 * ops
263 	 */
264 	if (!sess || !sess->se_tpg)
265 		goto out;
266 	rc = target_check_scsi2_reservation_conflict(cmd);
267 	if (rc == 1)
268 		goto out;
269 
270 	if (rc < 0)
271 		return TCM_RESERVATION_CONFLICT;
272 
273 	tpg = sess->se_tpg;
274 	spin_lock(&dev->dev_reservation_lock);
275 	if (dev->dev_reserved_node_acl &&
276 	   (dev->dev_reserved_node_acl != sess->se_node_acl)) {
277 		pr_err("SCSI-2 RESERVATION CONFLIFT for %s fabric\n",
278 			tpg->se_tpg_tfo->get_fabric_name());
279 		pr_err("Original reserver LUN: %u %s\n",
280 			cmd->se_lun->unpacked_lun,
281 			dev->dev_reserved_node_acl->initiatorname);
282 		pr_err("Current attempt - LUN: %u -> MAPPED LUN: %u"
283 			" from %s \n", cmd->se_lun->unpacked_lun,
284 			cmd->se_deve->mapped_lun,
285 			sess->se_node_acl->initiatorname);
286 		ret = TCM_RESERVATION_CONFLICT;
287 		goto out_unlock;
288 	}
289 
290 	dev->dev_reserved_node_acl = sess->se_node_acl;
291 	dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS;
292 	if (sess->sess_bin_isid != 0) {
293 		dev->dev_res_bin_isid = sess->sess_bin_isid;
294 		dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS_WITH_ISID;
295 	}
296 	pr_debug("SCSI-2 Reserved %s LUN: %u -> MAPPED LUN: %u"
297 		" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
298 		cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
299 		sess->se_node_acl->initiatorname);
300 
301 out_unlock:
302 	spin_unlock(&dev->dev_reservation_lock);
303 out:
304 	if (!ret)
305 		target_complete_cmd(cmd, GOOD);
306 	return ret;
307 }
308 
309 
310 /*
311  * Begin SPC-3/SPC-4 Persistent Reservations emulation support
312  *
313  * This function is called by those initiator ports who are *NOT*
314  * the active PR reservation holder when a reservation is present.
315  */
316 static int core_scsi3_pr_seq_non_holder(
317 	struct se_cmd *cmd,
318 	u32 pr_reg_type)
319 {
320 	unsigned char *cdb = cmd->t_task_cdb;
321 	struct se_dev_entry *se_deve;
322 	struct se_session *se_sess = cmd->se_sess;
323 	int other_cdb = 0, ignore_reg;
324 	int registered_nexus = 0, ret = 1; /* Conflict by default */
325 	int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
326 	int we = 0; /* Write Exclusive */
327 	int legacy = 0; /* Act like a legacy device and return
328 			 * RESERVATION CONFLICT on some CDBs */
329 
330 	se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
331 	/*
332 	 * Determine if the registration should be ignored due to
333 	 * non-matching ISIDs in target_scsi3_pr_reservation_check().
334 	 */
335 	ignore_reg = (pr_reg_type & 0x80000000);
336 	if (ignore_reg)
337 		pr_reg_type &= ~0x80000000;
338 
339 	switch (pr_reg_type) {
340 	case PR_TYPE_WRITE_EXCLUSIVE:
341 		we = 1;
342 	case PR_TYPE_EXCLUSIVE_ACCESS:
343 		/*
344 		 * Some commands are only allowed for the persistent reservation
345 		 * holder.
346 		 */
347 		if ((se_deve->def_pr_registered) && !(ignore_reg))
348 			registered_nexus = 1;
349 		break;
350 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
351 		we = 1;
352 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
353 		/*
354 		 * Some commands are only allowed for registered I_T Nexuses.
355 		 */
356 		reg_only = 1;
357 		if ((se_deve->def_pr_registered) && !(ignore_reg))
358 			registered_nexus = 1;
359 		break;
360 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
361 		we = 1;
362 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
363 		/*
364 		 * Each registered I_T Nexus is a reservation holder.
365 		 */
366 		all_reg = 1;
367 		if ((se_deve->def_pr_registered) && !(ignore_reg))
368 			registered_nexus = 1;
369 		break;
370 	default:
371 		return -EINVAL;
372 	}
373 	/*
374 	 * Referenced from spc4r17 table 45 for *NON* PR holder access
375 	 */
376 	switch (cdb[0]) {
377 	case SECURITY_PROTOCOL_IN:
378 		if (registered_nexus)
379 			return 0;
380 		ret = (we) ? 0 : 1;
381 		break;
382 	case MODE_SENSE:
383 	case MODE_SENSE_10:
384 	case READ_ATTRIBUTE:
385 	case READ_BUFFER:
386 	case RECEIVE_DIAGNOSTIC:
387 		if (legacy) {
388 			ret = 1;
389 			break;
390 		}
391 		if (registered_nexus) {
392 			ret = 0;
393 			break;
394 		}
395 		ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
396 		break;
397 	case PERSISTENT_RESERVE_OUT:
398 		/*
399 		 * This follows PERSISTENT_RESERVE_OUT service actions that
400 		 * are allowed in the presence of various reservations.
401 		 * See spc4r17, table 46
402 		 */
403 		switch (cdb[1] & 0x1f) {
404 		case PRO_CLEAR:
405 		case PRO_PREEMPT:
406 		case PRO_PREEMPT_AND_ABORT:
407 			ret = (registered_nexus) ? 0 : 1;
408 			break;
409 		case PRO_REGISTER:
410 		case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
411 			ret = 0;
412 			break;
413 		case PRO_REGISTER_AND_MOVE:
414 		case PRO_RESERVE:
415 			ret = 1;
416 			break;
417 		case PRO_RELEASE:
418 			ret = (registered_nexus) ? 0 : 1;
419 			break;
420 		default:
421 			pr_err("Unknown PERSISTENT_RESERVE_OUT service"
422 				" action: 0x%02x\n", cdb[1] & 0x1f);
423 			return -EINVAL;
424 		}
425 		break;
426 	case RELEASE:
427 	case RELEASE_10:
428 		/* Handled by CRH=1 in target_scsi2_reservation_release() */
429 		ret = 0;
430 		break;
431 	case RESERVE:
432 	case RESERVE_10:
433 		/* Handled by CRH=1 in target_scsi2_reservation_reserve() */
434 		ret = 0;
435 		break;
436 	case TEST_UNIT_READY:
437 		ret = (legacy) ? 1 : 0; /* Conflict for legacy */
438 		break;
439 	case MAINTENANCE_IN:
440 		switch (cdb[1] & 0x1f) {
441 		case MI_MANAGEMENT_PROTOCOL_IN:
442 			if (registered_nexus) {
443 				ret = 0;
444 				break;
445 			}
446 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
447 			break;
448 		case MI_REPORT_SUPPORTED_OPERATION_CODES:
449 		case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
450 			if (legacy) {
451 				ret = 1;
452 				break;
453 			}
454 			if (registered_nexus) {
455 				ret = 0;
456 				break;
457 			}
458 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
459 			break;
460 		case MI_REPORT_ALIASES:
461 		case MI_REPORT_IDENTIFYING_INFORMATION:
462 		case MI_REPORT_PRIORITY:
463 		case MI_REPORT_TARGET_PGS:
464 		case MI_REPORT_TIMESTAMP:
465 			ret = 0; /* Allowed */
466 			break;
467 		default:
468 			pr_err("Unknown MI Service Action: 0x%02x\n",
469 				(cdb[1] & 0x1f));
470 			return -EINVAL;
471 		}
472 		break;
473 	case ACCESS_CONTROL_IN:
474 	case ACCESS_CONTROL_OUT:
475 	case INQUIRY:
476 	case LOG_SENSE:
477 	case SERVICE_ACTION_IN_12:
478 	case REPORT_LUNS:
479 	case REQUEST_SENSE:
480 	case PERSISTENT_RESERVE_IN:
481 		ret = 0; /*/ Allowed CDBs */
482 		break;
483 	default:
484 		other_cdb = 1;
485 		break;
486 	}
487 	/*
488 	 * Case where the CDB is explicitly allowed in the above switch
489 	 * statement.
490 	 */
491 	if (!ret && !other_cdb) {
492 		pr_debug("Allowing explicit CDB: 0x%02x for %s"
493 			" reservation holder\n", cdb[0],
494 			core_scsi3_pr_dump_type(pr_reg_type));
495 
496 		return ret;
497 	}
498 	/*
499 	 * Check if write exclusive initiator ports *NOT* holding the
500 	 * WRITE_EXCLUSIVE_* reservation.
501 	 */
502 	if (we && !registered_nexus) {
503 		if (cmd->data_direction == DMA_TO_DEVICE) {
504 			/*
505 			 * Conflict for write exclusive
506 			 */
507 			pr_debug("%s Conflict for unregistered nexus"
508 				" %s CDB: 0x%02x to %s reservation\n",
509 				transport_dump_cmd_direction(cmd),
510 				se_sess->se_node_acl->initiatorname, cdb[0],
511 				core_scsi3_pr_dump_type(pr_reg_type));
512 			return 1;
513 		} else {
514 			/*
515 			 * Allow non WRITE CDBs for all Write Exclusive
516 			 * PR TYPEs to pass for registered and
517 			 * non-registered_nexuxes NOT holding the reservation.
518 			 *
519 			 * We only make noise for the unregisterd nexuses,
520 			 * as we expect registered non-reservation holding
521 			 * nexuses to issue CDBs.
522 			 */
523 
524 			if (!registered_nexus) {
525 				pr_debug("Allowing implicit CDB: 0x%02x"
526 					" for %s reservation on unregistered"
527 					" nexus\n", cdb[0],
528 					core_scsi3_pr_dump_type(pr_reg_type));
529 			}
530 
531 			return 0;
532 		}
533 	} else if ((reg_only) || (all_reg)) {
534 		if (registered_nexus) {
535 			/*
536 			 * For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
537 			 * allow commands from registered nexuses.
538 			 */
539 
540 			pr_debug("Allowing implicit CDB: 0x%02x for %s"
541 				" reservation\n", cdb[0],
542 				core_scsi3_pr_dump_type(pr_reg_type));
543 
544 			return 0;
545 		}
546        } else if (we && registered_nexus) {
547                /*
548                 * Reads are allowed for Write Exclusive locks
549                 * from all registrants.
550                 */
551                if (cmd->data_direction == DMA_FROM_DEVICE) {
552                        pr_debug("Allowing READ CDB: 0x%02x for %s"
553                                " reservation\n", cdb[0],
554                                core_scsi3_pr_dump_type(pr_reg_type));
555 
556                        return 0;
557                }
558 	}
559 	pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
560 		" for %s reservation\n", transport_dump_cmd_direction(cmd),
561 		(registered_nexus) ? "" : "un",
562 		se_sess->se_node_acl->initiatorname, cdb[0],
563 		core_scsi3_pr_dump_type(pr_reg_type));
564 
565 	return 1; /* Conflict by default */
566 }
567 
568 static sense_reason_t
569 target_scsi3_pr_reservation_check(struct se_cmd *cmd)
570 {
571 	struct se_device *dev = cmd->se_dev;
572 	struct se_session *sess = cmd->se_sess;
573 	u32 pr_reg_type;
574 
575 	if (!dev->dev_pr_res_holder)
576 		return 0;
577 
578 	pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
579 	cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
580 	if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
581 		goto check_nonholder;
582 
583 	if (dev->dev_pr_res_holder->isid_present_at_reg) {
584 		if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
585 		    sess->sess_bin_isid) {
586 			pr_reg_type |= 0x80000000;
587 			goto check_nonholder;
588 		}
589 	}
590 
591 	return 0;
592 
593 check_nonholder:
594 	if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type))
595 		return TCM_RESERVATION_CONFLICT;
596 	return 0;
597 }
598 
599 static u32 core_scsi3_pr_generation(struct se_device *dev)
600 {
601 	u32 prg;
602 
603 	/*
604 	 * PRGeneration field shall contain the value of a 32-bit wrapping
605 	 * counter mainted by the device server.
606 	 *
607 	 * Note that this is done regardless of Active Persist across
608 	 * Target PowerLoss (APTPL)
609 	 *
610 	 * See spc4r17 section 6.3.12 READ_KEYS service action
611 	 */
612 	spin_lock(&dev->dev_reservation_lock);
613 	prg = dev->t10_pr.pr_generation++;
614 	spin_unlock(&dev->dev_reservation_lock);
615 
616 	return prg;
617 }
618 
619 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
620 	struct se_device *dev,
621 	struct se_node_acl *nacl,
622 	struct se_dev_entry *deve,
623 	unsigned char *isid,
624 	u64 sa_res_key,
625 	int all_tg_pt,
626 	int aptpl)
627 {
628 	struct t10_pr_registration *pr_reg;
629 
630 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_ATOMIC);
631 	if (!pr_reg) {
632 		pr_err("Unable to allocate struct t10_pr_registration\n");
633 		return NULL;
634 	}
635 
636 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
637 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
638 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
639 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
640 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
641 	atomic_set(&pr_reg->pr_res_holders, 0);
642 	pr_reg->pr_reg_nacl = nacl;
643 	pr_reg->pr_reg_deve = deve;
644 	pr_reg->pr_res_mapped_lun = deve->mapped_lun;
645 	pr_reg->pr_aptpl_target_lun = deve->se_lun->unpacked_lun;
646 	pr_reg->pr_res_key = sa_res_key;
647 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
648 	pr_reg->pr_reg_aptpl = aptpl;
649 	pr_reg->pr_reg_tg_pt_lun = deve->se_lun;
650 	/*
651 	 * If an ISID value for this SCSI Initiator Port exists,
652 	 * save it to the registration now.
653 	 */
654 	if (isid != NULL) {
655 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
656 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
657 		pr_reg->isid_present_at_reg = 1;
658 	}
659 
660 	return pr_reg;
661 }
662 
663 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
664 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
665 
666 /*
667  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
668  * modes.
669  */
670 static struct t10_pr_registration *__core_scsi3_alloc_registration(
671 	struct se_device *dev,
672 	struct se_node_acl *nacl,
673 	struct se_dev_entry *deve,
674 	unsigned char *isid,
675 	u64 sa_res_key,
676 	int all_tg_pt,
677 	int aptpl)
678 {
679 	struct se_dev_entry *deve_tmp;
680 	struct se_node_acl *nacl_tmp;
681 	struct se_port *port, *port_tmp;
682 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
683 	struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
684 	int ret;
685 	/*
686 	 * Create a registration for the I_T Nexus upon which the
687 	 * PROUT REGISTER was received.
688 	 */
689 	pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, deve, isid,
690 			sa_res_key, all_tg_pt, aptpl);
691 	if (!pr_reg)
692 		return NULL;
693 	/*
694 	 * Return pointer to pr_reg for ALL_TG_PT=0
695 	 */
696 	if (!all_tg_pt)
697 		return pr_reg;
698 	/*
699 	 * Create list of matching SCSI Initiator Port registrations
700 	 * for ALL_TG_PT=1
701 	 */
702 	spin_lock(&dev->se_port_lock);
703 	list_for_each_entry_safe(port, port_tmp, &dev->dev_sep_list, sep_list) {
704 		atomic_inc_mb(&port->sep_tg_pt_ref_cnt);
705 		spin_unlock(&dev->se_port_lock);
706 
707 		spin_lock_bh(&port->sep_alua_lock);
708 		list_for_each_entry(deve_tmp, &port->sep_alua_list,
709 					alua_port_list) {
710 			/*
711 			 * This pointer will be NULL for demo mode MappedLUNs
712 			 * that have not been make explicit via a ConfigFS
713 			 * MappedLUN group for the SCSI Initiator Node ACL.
714 			 */
715 			if (!deve_tmp->se_lun_acl)
716 				continue;
717 
718 			nacl_tmp = deve_tmp->se_lun_acl->se_lun_nacl;
719 			/*
720 			 * Skip the matching struct se_node_acl that is allocated
721 			 * above..
722 			 */
723 			if (nacl == nacl_tmp)
724 				continue;
725 			/*
726 			 * Only perform PR registrations for target ports on
727 			 * the same fabric module as the REGISTER w/ ALL_TG_PT=1
728 			 * arrived.
729 			 */
730 			if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
731 				continue;
732 			/*
733 			 * Look for a matching Initiator Node ACL in ASCII format
734 			 */
735 			if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
736 				continue;
737 
738 			atomic_inc_mb(&deve_tmp->pr_ref_count);
739 			spin_unlock_bh(&port->sep_alua_lock);
740 			/*
741 			 * Grab a configfs group dependency that is released
742 			 * for the exception path at label out: below, or upon
743 			 * completion of adding ALL_TG_PT=1 registrations in
744 			 * __core_scsi3_add_registration()
745 			 */
746 			ret = core_scsi3_lunacl_depend_item(deve_tmp);
747 			if (ret < 0) {
748 				pr_err("core_scsi3_lunacl_depend"
749 						"_item() failed\n");
750 				atomic_dec_mb(&port->sep_tg_pt_ref_cnt);
751 				atomic_dec_mb(&deve_tmp->pr_ref_count);
752 				goto out;
753 			}
754 			/*
755 			 * Located a matching SCSI Initiator Port on a different
756 			 * port, allocate the pr_reg_atp and attach it to the
757 			 * pr_reg->pr_reg_atp_list that will be processed once
758 			 * the original *pr_reg is processed in
759 			 * __core_scsi3_add_registration()
760 			 */
761 			pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
762 						nacl_tmp, deve_tmp, NULL,
763 						sa_res_key, all_tg_pt, aptpl);
764 			if (!pr_reg_atp) {
765 				atomic_dec_mb(&port->sep_tg_pt_ref_cnt);
766 				atomic_dec_mb(&deve_tmp->pr_ref_count);
767 				core_scsi3_lunacl_undepend_item(deve_tmp);
768 				goto out;
769 			}
770 
771 			list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
772 				      &pr_reg->pr_reg_atp_list);
773 			spin_lock_bh(&port->sep_alua_lock);
774 		}
775 		spin_unlock_bh(&port->sep_alua_lock);
776 
777 		spin_lock(&dev->se_port_lock);
778 		atomic_dec_mb(&port->sep_tg_pt_ref_cnt);
779 	}
780 	spin_unlock(&dev->se_port_lock);
781 
782 	return pr_reg;
783 out:
784 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
785 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
786 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
787 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
788 		kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
789 	}
790 	kmem_cache_free(t10_pr_reg_cache, pr_reg);
791 	return NULL;
792 }
793 
794 int core_scsi3_alloc_aptpl_registration(
795 	struct t10_reservation *pr_tmpl,
796 	u64 sa_res_key,
797 	unsigned char *i_port,
798 	unsigned char *isid,
799 	u32 mapped_lun,
800 	unsigned char *t_port,
801 	u16 tpgt,
802 	u32 target_lun,
803 	int res_holder,
804 	int all_tg_pt,
805 	u8 type)
806 {
807 	struct t10_pr_registration *pr_reg;
808 
809 	if (!i_port || !t_port || !sa_res_key) {
810 		pr_err("Illegal parameters for APTPL registration\n");
811 		return -EINVAL;
812 	}
813 
814 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
815 	if (!pr_reg) {
816 		pr_err("Unable to allocate struct t10_pr_registration\n");
817 		return -ENOMEM;
818 	}
819 
820 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
821 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
822 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
823 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
824 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
825 	atomic_set(&pr_reg->pr_res_holders, 0);
826 	pr_reg->pr_reg_nacl = NULL;
827 	pr_reg->pr_reg_deve = NULL;
828 	pr_reg->pr_res_mapped_lun = mapped_lun;
829 	pr_reg->pr_aptpl_target_lun = target_lun;
830 	pr_reg->pr_res_key = sa_res_key;
831 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
832 	pr_reg->pr_reg_aptpl = 1;
833 	pr_reg->pr_reg_tg_pt_lun = NULL;
834 	pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
835 	pr_reg->pr_res_type = type;
836 	/*
837 	 * If an ISID value had been saved in APTPL metadata for this
838 	 * SCSI Initiator Port, restore it now.
839 	 */
840 	if (isid != NULL) {
841 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
842 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
843 		pr_reg->isid_present_at_reg = 1;
844 	}
845 	/*
846 	 * Copy the i_port and t_port information from caller.
847 	 */
848 	snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
849 	snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
850 	pr_reg->pr_reg_tpgt = tpgt;
851 	/*
852 	 * Set pr_res_holder from caller, the pr_reg who is the reservation
853 	 * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
854 	 * the Initiator Node LUN ACL from the fabric module is created for
855 	 * this registration.
856 	 */
857 	pr_reg->pr_res_holder = res_holder;
858 
859 	list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
860 	pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
861 			" metadata\n", (res_holder) ? "+reservation" : "");
862 	return 0;
863 }
864 
865 static void core_scsi3_aptpl_reserve(
866 	struct se_device *dev,
867 	struct se_portal_group *tpg,
868 	struct se_node_acl *node_acl,
869 	struct t10_pr_registration *pr_reg)
870 {
871 	char i_buf[PR_REG_ISID_ID_LEN];
872 
873 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
874 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
875 
876 	spin_lock(&dev->dev_reservation_lock);
877 	dev->dev_pr_res_holder = pr_reg;
878 	spin_unlock(&dev->dev_reservation_lock);
879 
880 	pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
881 		" new reservation holder TYPE: %s ALL_TG_PT: %d\n",
882 		tpg->se_tpg_tfo->get_fabric_name(),
883 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
884 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
885 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
886 		tpg->se_tpg_tfo->get_fabric_name(), node_acl->initiatorname,
887 		i_buf);
888 }
889 
890 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
891 				struct t10_pr_registration *, enum register_type, int);
892 
893 static int __core_scsi3_check_aptpl_registration(
894 	struct se_device *dev,
895 	struct se_portal_group *tpg,
896 	struct se_lun *lun,
897 	u32 target_lun,
898 	struct se_node_acl *nacl,
899 	struct se_dev_entry *deve)
900 {
901 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
902 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
903 	unsigned char i_port[PR_APTPL_MAX_IPORT_LEN];
904 	unsigned char t_port[PR_APTPL_MAX_TPORT_LEN];
905 	u16 tpgt;
906 
907 	memset(i_port, 0, PR_APTPL_MAX_IPORT_LEN);
908 	memset(t_port, 0, PR_APTPL_MAX_TPORT_LEN);
909 	/*
910 	 * Copy Initiator Port information from struct se_node_acl
911 	 */
912 	snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
913 	snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
914 			tpg->se_tpg_tfo->tpg_get_wwn(tpg));
915 	tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
916 	/*
917 	 * Look for the matching registrations+reservation from those
918 	 * created from APTPL metadata.  Note that multiple registrations
919 	 * may exist for fabrics that use ISIDs in their SCSI Initiator Port
920 	 * TransportIDs.
921 	 */
922 	spin_lock(&pr_tmpl->aptpl_reg_lock);
923 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
924 				pr_reg_aptpl_list) {
925 
926 		if (!strcmp(pr_reg->pr_iport, i_port) &&
927 		     (pr_reg->pr_res_mapped_lun == deve->mapped_lun) &&
928 		    !(strcmp(pr_reg->pr_tport, t_port)) &&
929 		     (pr_reg->pr_reg_tpgt == tpgt) &&
930 		     (pr_reg->pr_aptpl_target_lun == target_lun)) {
931 
932 			pr_reg->pr_reg_nacl = nacl;
933 			pr_reg->pr_reg_deve = deve;
934 			pr_reg->pr_reg_tg_pt_lun = lun;
935 
936 			list_del(&pr_reg->pr_reg_aptpl_list);
937 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
938 			/*
939 			 * At this point all of the pointers in *pr_reg will
940 			 * be setup, so go ahead and add the registration.
941 			 */
942 
943 			__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
944 			/*
945 			 * If this registration is the reservation holder,
946 			 * make that happen now..
947 			 */
948 			if (pr_reg->pr_res_holder)
949 				core_scsi3_aptpl_reserve(dev, tpg,
950 						nacl, pr_reg);
951 			/*
952 			 * Reenable pr_aptpl_active to accept new metadata
953 			 * updates once the SCSI device is active again..
954 			 */
955 			spin_lock(&pr_tmpl->aptpl_reg_lock);
956 			pr_tmpl->pr_aptpl_active = 1;
957 		}
958 	}
959 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
960 
961 	return 0;
962 }
963 
964 int core_scsi3_check_aptpl_registration(
965 	struct se_device *dev,
966 	struct se_portal_group *tpg,
967 	struct se_lun *lun,
968 	struct se_node_acl *nacl,
969 	u32 mapped_lun)
970 {
971 	struct se_dev_entry *deve = nacl->device_list[mapped_lun];
972 
973 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
974 		return 0;
975 
976 	return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
977 				lun->unpacked_lun, nacl, deve);
978 }
979 
980 static void __core_scsi3_dump_registration(
981 	const struct target_core_fabric_ops *tfo,
982 	struct se_device *dev,
983 	struct se_node_acl *nacl,
984 	struct t10_pr_registration *pr_reg,
985 	enum register_type register_type)
986 {
987 	struct se_portal_group *se_tpg = nacl->se_tpg;
988 	char i_buf[PR_REG_ISID_ID_LEN];
989 
990 	memset(&i_buf[0], 0, PR_REG_ISID_ID_LEN);
991 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
992 
993 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
994 		" Node: %s%s\n", tfo->get_fabric_name(), (register_type == REGISTER_AND_MOVE) ?
995 		"_AND_MOVE" : (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ?
996 		"_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
997 		i_buf);
998 	pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
999 		 tfo->get_fabric_name(), tfo->tpg_get_wwn(se_tpg),
1000 		tfo->tpg_get_tag(se_tpg));
1001 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1002 		" Port(s)\n",  tfo->get_fabric_name(),
1003 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1004 		dev->transport->name);
1005 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1006 		" 0x%08x  APTPL: %d\n", tfo->get_fabric_name(),
1007 		pr_reg->pr_res_key, pr_reg->pr_res_generation,
1008 		pr_reg->pr_reg_aptpl);
1009 }
1010 
1011 /*
1012  * this function can be called with struct se_device->dev_reservation_lock
1013  * when register_move = 1
1014  */
1015 static void __core_scsi3_add_registration(
1016 	struct se_device *dev,
1017 	struct se_node_acl *nacl,
1018 	struct t10_pr_registration *pr_reg,
1019 	enum register_type register_type,
1020 	int register_move)
1021 {
1022 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1023 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1024 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1025 
1026 	/*
1027 	 * Increment PRgeneration counter for struct se_device upon a successful
1028 	 * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1029 	 *
1030 	 * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1031 	 * action, the struct se_device->dev_reservation_lock will already be held,
1032 	 * so we do not call core_scsi3_pr_generation() which grabs the lock
1033 	 * for the REGISTER.
1034 	 */
1035 	pr_reg->pr_res_generation = (register_move) ?
1036 			dev->t10_pr.pr_generation++ :
1037 			core_scsi3_pr_generation(dev);
1038 
1039 	spin_lock(&pr_tmpl->registration_lock);
1040 	list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1041 	pr_reg->pr_reg_deve->def_pr_registered = 1;
1042 
1043 	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1044 	spin_unlock(&pr_tmpl->registration_lock);
1045 	/*
1046 	 * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1047 	 */
1048 	if (!pr_reg->pr_reg_all_tg_pt || register_move)
1049 		return;
1050 	/*
1051 	 * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1052 	 * allocated in __core_scsi3_alloc_registration()
1053 	 */
1054 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1055 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1056 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1057 
1058 		pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1059 
1060 		spin_lock(&pr_tmpl->registration_lock);
1061 		list_add_tail(&pr_reg_tmp->pr_reg_list,
1062 			      &pr_tmpl->registration_list);
1063 		pr_reg_tmp->pr_reg_deve->def_pr_registered = 1;
1064 
1065 		__core_scsi3_dump_registration(tfo, dev,
1066 				pr_reg_tmp->pr_reg_nacl, pr_reg_tmp,
1067 				register_type);
1068 		spin_unlock(&pr_tmpl->registration_lock);
1069 		/*
1070 		 * Drop configfs group dependency reference from
1071 		 * __core_scsi3_alloc_registration()
1072 		 */
1073 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1074 	}
1075 }
1076 
1077 static int core_scsi3_alloc_registration(
1078 	struct se_device *dev,
1079 	struct se_node_acl *nacl,
1080 	struct se_dev_entry *deve,
1081 	unsigned char *isid,
1082 	u64 sa_res_key,
1083 	int all_tg_pt,
1084 	int aptpl,
1085 	enum register_type register_type,
1086 	int register_move)
1087 {
1088 	struct t10_pr_registration *pr_reg;
1089 
1090 	pr_reg = __core_scsi3_alloc_registration(dev, nacl, deve, isid,
1091 			sa_res_key, all_tg_pt, aptpl);
1092 	if (!pr_reg)
1093 		return -EPERM;
1094 
1095 	__core_scsi3_add_registration(dev, nacl, pr_reg,
1096 			register_type, register_move);
1097 	return 0;
1098 }
1099 
1100 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1101 	struct se_device *dev,
1102 	struct se_node_acl *nacl,
1103 	unsigned char *isid)
1104 {
1105 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1106 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1107 	struct se_portal_group *tpg;
1108 
1109 	spin_lock(&pr_tmpl->registration_lock);
1110 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1111 			&pr_tmpl->registration_list, pr_reg_list) {
1112 		/*
1113 		 * First look for a matching struct se_node_acl
1114 		 */
1115 		if (pr_reg->pr_reg_nacl != nacl)
1116 			continue;
1117 
1118 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1119 		/*
1120 		 * If this registration does NOT contain a fabric provided
1121 		 * ISID, then we have found a match.
1122 		 */
1123 		if (!pr_reg->isid_present_at_reg) {
1124 			/*
1125 			 * Determine if this SCSI device server requires that
1126 			 * SCSI Intiatior TransportID w/ ISIDs is enforced
1127 			 * for fabric modules (iSCSI) requiring them.
1128 			 */
1129 			if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1130 				if (dev->dev_attrib.enforce_pr_isids)
1131 					continue;
1132 			}
1133 			atomic_inc_mb(&pr_reg->pr_res_holders);
1134 			spin_unlock(&pr_tmpl->registration_lock);
1135 			return pr_reg;
1136 		}
1137 		/*
1138 		 * If the *pr_reg contains a fabric defined ISID for multi-value
1139 		 * SCSI Initiator Port TransportIDs, then we expect a valid
1140 		 * matching ISID to be provided by the local SCSI Initiator Port.
1141 		 */
1142 		if (!isid)
1143 			continue;
1144 		if (strcmp(isid, pr_reg->pr_reg_isid))
1145 			continue;
1146 
1147 		atomic_inc_mb(&pr_reg->pr_res_holders);
1148 		spin_unlock(&pr_tmpl->registration_lock);
1149 		return pr_reg;
1150 	}
1151 	spin_unlock(&pr_tmpl->registration_lock);
1152 
1153 	return NULL;
1154 }
1155 
1156 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1157 	struct se_device *dev,
1158 	struct se_node_acl *nacl,
1159 	struct se_session *sess)
1160 {
1161 	struct se_portal_group *tpg = nacl->se_tpg;
1162 	unsigned char buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
1163 
1164 	if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1165 		memset(&buf[0], 0, PR_REG_ISID_LEN);
1166 		tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1167 					PR_REG_ISID_LEN);
1168 		isid_ptr = &buf[0];
1169 	}
1170 
1171 	return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1172 }
1173 
1174 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1175 {
1176 	atomic_dec_mb(&pr_reg->pr_res_holders);
1177 }
1178 
1179 static int core_scsi3_check_implicit_release(
1180 	struct se_device *dev,
1181 	struct t10_pr_registration *pr_reg)
1182 {
1183 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1184 	struct t10_pr_registration *pr_res_holder;
1185 	int ret = 0;
1186 
1187 	spin_lock(&dev->dev_reservation_lock);
1188 	pr_res_holder = dev->dev_pr_res_holder;
1189 	if (!pr_res_holder) {
1190 		spin_unlock(&dev->dev_reservation_lock);
1191 		return ret;
1192 	}
1193 	if (pr_res_holder == pr_reg) {
1194 		/*
1195 		 * Perform an implicit RELEASE if the registration that
1196 		 * is being released is holding the reservation.
1197 		 *
1198 		 * From spc4r17, section 5.7.11.1:
1199 		 *
1200 		 * e) If the I_T nexus is the persistent reservation holder
1201 		 *    and the persistent reservation is not an all registrants
1202 		 *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1203 		 *    service action or REGISTER AND  IGNORE EXISTING KEY
1204 		 *    service action with the SERVICE ACTION RESERVATION KEY
1205 		 *    field set to zero (see 5.7.11.3).
1206 		 */
1207 		__core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0, 1);
1208 		ret = 1;
1209 		/*
1210 		 * For 'All Registrants' reservation types, all existing
1211 		 * registrations are still processed as reservation holders
1212 		 * in core_scsi3_pr_seq_non_holder() after the initial
1213 		 * reservation holder is implicitly released here.
1214 		 */
1215 	} else if (pr_reg->pr_reg_all_tg_pt &&
1216 		  (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1217 			  pr_reg->pr_reg_nacl->initiatorname)) &&
1218 		  (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1219 		pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1220 			" UNREGISTER while existing reservation with matching"
1221 			" key 0x%016Lx is present from another SCSI Initiator"
1222 			" Port\n", pr_reg->pr_res_key);
1223 		ret = -EPERM;
1224 	}
1225 	spin_unlock(&dev->dev_reservation_lock);
1226 
1227 	return ret;
1228 }
1229 
1230 /*
1231  * Called with struct t10_reservation->registration_lock held.
1232  */
1233 static void __core_scsi3_free_registration(
1234 	struct se_device *dev,
1235 	struct t10_pr_registration *pr_reg,
1236 	struct list_head *preempt_and_abort_list,
1237 	int dec_holders)
1238 	__releases(&pr_tmpl->registration_lock)
1239 	__acquires(&pr_tmpl->registration_lock)
1240 {
1241 	const struct target_core_fabric_ops *tfo =
1242 			pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1243 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1244 	char i_buf[PR_REG_ISID_ID_LEN];
1245 
1246 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1247 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1248 
1249 	pr_reg->pr_reg_deve->def_pr_registered = 0;
1250 	pr_reg->pr_reg_deve->pr_res_key = 0;
1251 	if (!list_empty(&pr_reg->pr_reg_list))
1252 		list_del(&pr_reg->pr_reg_list);
1253 	/*
1254 	 * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1255 	 * so call core_scsi3_put_pr_reg() to decrement our reference.
1256 	 */
1257 	if (dec_holders)
1258 		core_scsi3_put_pr_reg(pr_reg);
1259 	/*
1260 	 * Wait until all reference from any other I_T nexuses for this
1261 	 * *pr_reg have been released.  Because list_del() is called above,
1262 	 * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1263 	 * count back to zero, and we release *pr_reg.
1264 	 */
1265 	while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1266 		spin_unlock(&pr_tmpl->registration_lock);
1267 		pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1268 				tfo->get_fabric_name());
1269 		cpu_relax();
1270 		spin_lock(&pr_tmpl->registration_lock);
1271 	}
1272 
1273 	pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1274 		" Node: %s%s\n", tfo->get_fabric_name(),
1275 		pr_reg->pr_reg_nacl->initiatorname,
1276 		i_buf);
1277 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1278 		" Port(s)\n", tfo->get_fabric_name(),
1279 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1280 		dev->transport->name);
1281 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1282 		" 0x%08x\n", tfo->get_fabric_name(), pr_reg->pr_res_key,
1283 		pr_reg->pr_res_generation);
1284 
1285 	if (!preempt_and_abort_list) {
1286 		pr_reg->pr_reg_deve = NULL;
1287 		pr_reg->pr_reg_nacl = NULL;
1288 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1289 		return;
1290 	}
1291 	/*
1292 	 * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1293 	 * are released once the ABORT_TASK_SET has completed..
1294 	 */
1295 	list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1296 }
1297 
1298 void core_scsi3_free_pr_reg_from_nacl(
1299 	struct se_device *dev,
1300 	struct se_node_acl *nacl)
1301 {
1302 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1303 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1304 	bool free_reg = false;
1305 	/*
1306 	 * If the passed se_node_acl matches the reservation holder,
1307 	 * release the reservation.
1308 	 */
1309 	spin_lock(&dev->dev_reservation_lock);
1310 	pr_res_holder = dev->dev_pr_res_holder;
1311 	if ((pr_res_holder != NULL) &&
1312 	    (pr_res_holder->pr_reg_nacl == nacl)) {
1313 		__core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0, 1);
1314 		free_reg = true;
1315 	}
1316 	spin_unlock(&dev->dev_reservation_lock);
1317 	/*
1318 	 * Release any registration associated with the struct se_node_acl.
1319 	 */
1320 	spin_lock(&pr_tmpl->registration_lock);
1321 	if (pr_res_holder && free_reg)
1322 		__core_scsi3_free_registration(dev, pr_res_holder, NULL, 0);
1323 
1324 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1325 			&pr_tmpl->registration_list, pr_reg_list) {
1326 
1327 		if (pr_reg->pr_reg_nacl != nacl)
1328 			continue;
1329 
1330 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1331 	}
1332 	spin_unlock(&pr_tmpl->registration_lock);
1333 }
1334 
1335 void core_scsi3_free_all_registrations(
1336 	struct se_device *dev)
1337 {
1338 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1339 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1340 
1341 	spin_lock(&dev->dev_reservation_lock);
1342 	pr_res_holder = dev->dev_pr_res_holder;
1343 	if (pr_res_holder != NULL) {
1344 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1345 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
1346 						  pr_res_holder, 0, 0);
1347 	}
1348 	spin_unlock(&dev->dev_reservation_lock);
1349 
1350 	spin_lock(&pr_tmpl->registration_lock);
1351 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1352 			&pr_tmpl->registration_list, pr_reg_list) {
1353 
1354 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1355 	}
1356 	spin_unlock(&pr_tmpl->registration_lock);
1357 
1358 	spin_lock(&pr_tmpl->aptpl_reg_lock);
1359 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1360 				pr_reg_aptpl_list) {
1361 		list_del(&pr_reg->pr_reg_aptpl_list);
1362 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1363 	}
1364 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
1365 }
1366 
1367 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1368 {
1369 	return target_depend_item(&tpg->tpg_group.cg_item);
1370 }
1371 
1372 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1373 {
1374 	target_undepend_item(&tpg->tpg_group.cg_item);
1375 	atomic_dec_mb(&tpg->tpg_pr_ref_count);
1376 }
1377 
1378 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1379 {
1380 	if (nacl->dynamic_node_acl)
1381 		return 0;
1382 	return target_depend_item(&nacl->acl_group.cg_item);
1383 }
1384 
1385 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1386 {
1387 	if (!nacl->dynamic_node_acl)
1388 		target_undepend_item(&nacl->acl_group.cg_item);
1389 	atomic_dec_mb(&nacl->acl_pr_ref_count);
1390 }
1391 
1392 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1393 {
1394 	struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1395 	struct se_node_acl *nacl;
1396 	struct se_portal_group *tpg;
1397 	/*
1398 	 * For nacl->dynamic_node_acl=1
1399 	 */
1400 	if (!lun_acl)
1401 		return 0;
1402 
1403 	nacl = lun_acl->se_lun_nacl;
1404 	tpg = nacl->se_tpg;
1405 
1406 	return target_depend_item(&lun_acl->se_lun_group.cg_item);
1407 }
1408 
1409 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1410 {
1411 	struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1412 	struct se_node_acl *nacl;
1413 	struct se_portal_group *tpg;
1414 	/*
1415 	 * For nacl->dynamic_node_acl=1
1416 	 */
1417 	if (!lun_acl) {
1418 		atomic_dec_mb(&se_deve->pr_ref_count);
1419 		return;
1420 	}
1421 	nacl = lun_acl->se_lun_nacl;
1422 	tpg = nacl->se_tpg;
1423 
1424 	target_undepend_item(&lun_acl->se_lun_group.cg_item);
1425 	atomic_dec_mb(&se_deve->pr_ref_count);
1426 }
1427 
1428 static sense_reason_t
1429 core_scsi3_decode_spec_i_port(
1430 	struct se_cmd *cmd,
1431 	struct se_portal_group *tpg,
1432 	unsigned char *l_isid,
1433 	u64 sa_res_key,
1434 	int all_tg_pt,
1435 	int aptpl)
1436 {
1437 	struct se_device *dev = cmd->se_dev;
1438 	struct se_port *tmp_port;
1439 	struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1440 	struct se_session *se_sess = cmd->se_sess;
1441 	struct se_node_acl *dest_node_acl = NULL;
1442 	struct se_dev_entry *dest_se_deve = NULL, *local_se_deve;
1443 	struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1444 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1445 	LIST_HEAD(tid_dest_list);
1446 	struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1447 	const struct target_core_fabric_ops *tmp_tf_ops;
1448 	unsigned char *buf;
1449 	unsigned char *ptr, *i_str = NULL, proto_ident, tmp_proto_ident;
1450 	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
1451 	sense_reason_t ret;
1452 	u32 tpdl, tid_len = 0;
1453 	int dest_local_nexus;
1454 	u32 dest_rtpi = 0;
1455 
1456 	local_se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
1457 	/*
1458 	 * Allocate a struct pr_transport_id_holder and setup the
1459 	 * local_node_acl and local_se_deve pointers and add to
1460 	 * struct list_head tid_dest_list for add registration
1461 	 * processing in the loop of tid_dest_list below.
1462 	 */
1463 	tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1464 	if (!tidh_new) {
1465 		pr_err("Unable to allocate tidh_new\n");
1466 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1467 	}
1468 	INIT_LIST_HEAD(&tidh_new->dest_list);
1469 	tidh_new->dest_tpg = tpg;
1470 	tidh_new->dest_node_acl = se_sess->se_node_acl;
1471 	tidh_new->dest_se_deve = local_se_deve;
1472 
1473 	local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1474 				se_sess->se_node_acl, local_se_deve, l_isid,
1475 				sa_res_key, all_tg_pt, aptpl);
1476 	if (!local_pr_reg) {
1477 		kfree(tidh_new);
1478 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1479 	}
1480 	tidh_new->dest_pr_reg = local_pr_reg;
1481 	/*
1482 	 * The local I_T nexus does not hold any configfs dependances,
1483 	 * so we set tid_h->dest_local_nexus=1 to prevent the
1484 	 * configfs_undepend_item() calls in the tid_dest_list loops below.
1485 	 */
1486 	tidh_new->dest_local_nexus = 1;
1487 	list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1488 
1489 	if (cmd->data_length < 28) {
1490 		pr_warn("SPC-PR: Received PR OUT parameter list"
1491 			" length too small: %u\n", cmd->data_length);
1492 		ret = TCM_INVALID_PARAMETER_LIST;
1493 		goto out;
1494 	}
1495 
1496 	buf = transport_kmap_data_sg(cmd);
1497 	if (!buf) {
1498 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1499 		goto out;
1500 	}
1501 
1502 	/*
1503 	 * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1504 	 * first extract TransportID Parameter Data Length, and make sure
1505 	 * the value matches up to the SCSI expected data transfer length.
1506 	 */
1507 	tpdl = (buf[24] & 0xff) << 24;
1508 	tpdl |= (buf[25] & 0xff) << 16;
1509 	tpdl |= (buf[26] & 0xff) << 8;
1510 	tpdl |= buf[27] & 0xff;
1511 
1512 	if ((tpdl + 28) != cmd->data_length) {
1513 		pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1514 			" does not equal CDB data_length: %u\n", tpdl,
1515 			cmd->data_length);
1516 		ret = TCM_INVALID_PARAMETER_LIST;
1517 		goto out_unmap;
1518 	}
1519 	/*
1520 	 * Start processing the received transport IDs using the
1521 	 * receiving I_T Nexus portal's fabric dependent methods to
1522 	 * obtain the SCSI Initiator Port/Device Identifiers.
1523 	 */
1524 	ptr = &buf[28];
1525 
1526 	while (tpdl > 0) {
1527 		proto_ident = (ptr[0] & 0x0f);
1528 		dest_tpg = NULL;
1529 
1530 		spin_lock(&dev->se_port_lock);
1531 		list_for_each_entry(tmp_port, &dev->dev_sep_list, sep_list) {
1532 			tmp_tpg = tmp_port->sep_tpg;
1533 			if (!tmp_tpg)
1534 				continue;
1535 			tmp_tf_ops = tmp_tpg->se_tpg_tfo;
1536 			if (!tmp_tf_ops)
1537 				continue;
1538 			if (!tmp_tf_ops->get_fabric_proto_ident ||
1539 			    !tmp_tf_ops->tpg_parse_pr_out_transport_id)
1540 				continue;
1541 			/*
1542 			 * Look for the matching proto_ident provided by
1543 			 * the received TransportID
1544 			 */
1545 			tmp_proto_ident = tmp_tf_ops->get_fabric_proto_ident(tmp_tpg);
1546 			if (tmp_proto_ident != proto_ident)
1547 				continue;
1548 			dest_rtpi = tmp_port->sep_rtpi;
1549 
1550 			i_str = tmp_tf_ops->tpg_parse_pr_out_transport_id(
1551 					tmp_tpg, (const char *)ptr, &tid_len,
1552 					&iport_ptr);
1553 			if (!i_str)
1554 				continue;
1555 
1556 			atomic_inc_mb(&tmp_tpg->tpg_pr_ref_count);
1557 			spin_unlock(&dev->se_port_lock);
1558 
1559 			if (core_scsi3_tpg_depend_item(tmp_tpg)) {
1560 				pr_err(" core_scsi3_tpg_depend_item()"
1561 					" for tmp_tpg\n");
1562 				atomic_dec_mb(&tmp_tpg->tpg_pr_ref_count);
1563 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1564 				goto out_unmap;
1565 			}
1566 			/*
1567 			 * Locate the destination initiator ACL to be registered
1568 			 * from the decoded fabric module specific TransportID
1569 			 * at *i_str.
1570 			 */
1571 			spin_lock_irq(&tmp_tpg->acl_node_lock);
1572 			dest_node_acl = __core_tpg_get_initiator_node_acl(
1573 						tmp_tpg, i_str);
1574 			if (dest_node_acl)
1575 				atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
1576 			spin_unlock_irq(&tmp_tpg->acl_node_lock);
1577 
1578 			if (!dest_node_acl) {
1579 				core_scsi3_tpg_undepend_item(tmp_tpg);
1580 				spin_lock(&dev->se_port_lock);
1581 				continue;
1582 			}
1583 
1584 			if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
1585 				pr_err("configfs_depend_item() failed"
1586 					" for dest_node_acl->acl_group\n");
1587 				atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
1588 				core_scsi3_tpg_undepend_item(tmp_tpg);
1589 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1590 				goto out_unmap;
1591 			}
1592 
1593 			dest_tpg = tmp_tpg;
1594 			pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1595 				" %s Port RTPI: %hu\n",
1596 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1597 				dest_node_acl->initiatorname, dest_rtpi);
1598 
1599 			spin_lock(&dev->se_port_lock);
1600 			break;
1601 		}
1602 		spin_unlock(&dev->se_port_lock);
1603 
1604 		if (!dest_tpg) {
1605 			pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1606 					" dest_tpg\n");
1607 			ret = TCM_INVALID_PARAMETER_LIST;
1608 			goto out_unmap;
1609 		}
1610 
1611 		pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1612 			" tid_len: %d for %s + %s\n",
1613 			dest_tpg->se_tpg_tfo->get_fabric_name(), cmd->data_length,
1614 			tpdl, tid_len, i_str, iport_ptr);
1615 
1616 		if (tid_len > tpdl) {
1617 			pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1618 				" %u for Transport ID: %s\n", tid_len, ptr);
1619 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1620 			core_scsi3_tpg_undepend_item(dest_tpg);
1621 			ret = TCM_INVALID_PARAMETER_LIST;
1622 			goto out_unmap;
1623 		}
1624 		/*
1625 		 * Locate the desintation struct se_dev_entry pointer for matching
1626 		 * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1627 		 * Target Port.
1628 		 */
1629 		dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1630 					dest_rtpi);
1631 		if (!dest_se_deve) {
1632 			pr_err("Unable to locate %s dest_se_deve"
1633 				" from destination RTPI: %hu\n",
1634 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1635 				dest_rtpi);
1636 
1637 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1638 			core_scsi3_tpg_undepend_item(dest_tpg);
1639 			ret = TCM_INVALID_PARAMETER_LIST;
1640 			goto out_unmap;
1641 		}
1642 
1643 		if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
1644 			pr_err("core_scsi3_lunacl_depend_item()"
1645 					" failed\n");
1646 			atomic_dec_mb(&dest_se_deve->pr_ref_count);
1647 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1648 			core_scsi3_tpg_undepend_item(dest_tpg);
1649 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1650 			goto out_unmap;
1651 		}
1652 
1653 		pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1654 			" dest_se_deve mapped_lun: %u\n",
1655 			dest_tpg->se_tpg_tfo->get_fabric_name(),
1656 			dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1657 
1658 		/*
1659 		 * Skip any TransportIDs that already have a registration for
1660 		 * this target port.
1661 		 */
1662 		pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1663 					iport_ptr);
1664 		if (pr_reg_e) {
1665 			core_scsi3_put_pr_reg(pr_reg_e);
1666 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1667 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1668 			core_scsi3_tpg_undepend_item(dest_tpg);
1669 			ptr += tid_len;
1670 			tpdl -= tid_len;
1671 			tid_len = 0;
1672 			continue;
1673 		}
1674 		/*
1675 		 * Allocate a struct pr_transport_id_holder and setup
1676 		 * the dest_node_acl and dest_se_deve pointers for the
1677 		 * loop below.
1678 		 */
1679 		tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1680 				GFP_KERNEL);
1681 		if (!tidh_new) {
1682 			pr_err("Unable to allocate tidh_new\n");
1683 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1684 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1685 			core_scsi3_tpg_undepend_item(dest_tpg);
1686 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1687 			goto out_unmap;
1688 		}
1689 		INIT_LIST_HEAD(&tidh_new->dest_list);
1690 		tidh_new->dest_tpg = dest_tpg;
1691 		tidh_new->dest_node_acl = dest_node_acl;
1692 		tidh_new->dest_se_deve = dest_se_deve;
1693 
1694 		/*
1695 		 * Allocate, but do NOT add the registration for the
1696 		 * TransportID referenced SCSI Initiator port.  This
1697 		 * done because of the following from spc4r17 in section
1698 		 * 6.14.3 wrt SPEC_I_PT:
1699 		 *
1700 		 * "If a registration fails for any initiator port (e.g., if th
1701 		 * logical unit does not have enough resources available to
1702 		 * hold the registration information), no registrations shall be
1703 		 * made, and the command shall be terminated with
1704 		 * CHECK CONDITION status."
1705 		 *
1706 		 * That means we call __core_scsi3_alloc_registration() here,
1707 		 * and then call __core_scsi3_add_registration() in the
1708 		 * 2nd loop which will never fail.
1709 		 */
1710 		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1711 				dest_node_acl, dest_se_deve, iport_ptr,
1712 				sa_res_key, all_tg_pt, aptpl);
1713 		if (!dest_pr_reg) {
1714 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1715 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1716 			core_scsi3_tpg_undepend_item(dest_tpg);
1717 			kfree(tidh_new);
1718 			ret = TCM_INVALID_PARAMETER_LIST;
1719 			goto out_unmap;
1720 		}
1721 		tidh_new->dest_pr_reg = dest_pr_reg;
1722 		list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1723 
1724 		ptr += tid_len;
1725 		tpdl -= tid_len;
1726 		tid_len = 0;
1727 
1728 	}
1729 
1730 	transport_kunmap_data_sg(cmd);
1731 
1732 	/*
1733 	 * Go ahead and create a registrations from tid_dest_list for the
1734 	 * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1735 	 * and dest_se_deve.
1736 	 *
1737 	 * The SA Reservation Key from the PROUT is set for the
1738 	 * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1739 	 * means that the TransportID Initiator port will be
1740 	 * registered on all of the target ports in the SCSI target device
1741 	 * ALL_TG_PT=0 means the registration will only be for the
1742 	 * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1743 	 * was received.
1744 	 */
1745 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1746 		dest_tpg = tidh->dest_tpg;
1747 		dest_node_acl = tidh->dest_node_acl;
1748 		dest_se_deve = tidh->dest_se_deve;
1749 		dest_pr_reg = tidh->dest_pr_reg;
1750 		dest_local_nexus = tidh->dest_local_nexus;
1751 
1752 		list_del(&tidh->dest_list);
1753 		kfree(tidh);
1754 
1755 		memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1756 		core_pr_dump_initiator_port(dest_pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1757 
1758 		__core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1759 					dest_pr_reg, 0, 0);
1760 
1761 		pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1762 			" registered Transport ID for Node: %s%s Mapped LUN:"
1763 			" %u\n", dest_tpg->se_tpg_tfo->get_fabric_name(),
1764 			dest_node_acl->initiatorname, i_buf, dest_se_deve->mapped_lun);
1765 
1766 		if (dest_local_nexus)
1767 			continue;
1768 
1769 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1770 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1771 		core_scsi3_tpg_undepend_item(dest_tpg);
1772 	}
1773 
1774 	return 0;
1775 out_unmap:
1776 	transport_kunmap_data_sg(cmd);
1777 out:
1778 	/*
1779 	 * For the failure case, release everything from tid_dest_list
1780 	 * including *dest_pr_reg and the configfs dependances..
1781 	 */
1782 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1783 		dest_tpg = tidh->dest_tpg;
1784 		dest_node_acl = tidh->dest_node_acl;
1785 		dest_se_deve = tidh->dest_se_deve;
1786 		dest_pr_reg = tidh->dest_pr_reg;
1787 		dest_local_nexus = tidh->dest_local_nexus;
1788 
1789 		list_del(&tidh->dest_list);
1790 		kfree(tidh);
1791 		/*
1792 		 * Release any extra ALL_TG_PT=1 registrations for
1793 		 * the SPEC_I_PT=1 case.
1794 		 */
1795 		list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1796 				&dest_pr_reg->pr_reg_atp_list,
1797 				pr_reg_atp_mem_list) {
1798 			list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1799 			core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1800 			kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1801 		}
1802 
1803 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1804 
1805 		if (dest_local_nexus)
1806 			continue;
1807 
1808 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1809 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1810 		core_scsi3_tpg_undepend_item(dest_tpg);
1811 	}
1812 	return ret;
1813 }
1814 
1815 static int core_scsi3_update_aptpl_buf(
1816 	struct se_device *dev,
1817 	unsigned char *buf,
1818 	u32 pr_aptpl_buf_len)
1819 {
1820 	struct se_lun *lun;
1821 	struct se_portal_group *tpg;
1822 	struct t10_pr_registration *pr_reg;
1823 	unsigned char tmp[512], isid_buf[32];
1824 	ssize_t len = 0;
1825 	int reg_count = 0;
1826 	int ret = 0;
1827 
1828 	spin_lock(&dev->dev_reservation_lock);
1829 	spin_lock(&dev->t10_pr.registration_lock);
1830 	/*
1831 	 * Walk the registration list..
1832 	 */
1833 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
1834 			pr_reg_list) {
1835 
1836 		tmp[0] = '\0';
1837 		isid_buf[0] = '\0';
1838 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1839 		lun = pr_reg->pr_reg_tg_pt_lun;
1840 		/*
1841 		 * Write out any ISID value to APTPL metadata that was included
1842 		 * in the original registration.
1843 		 */
1844 		if (pr_reg->isid_present_at_reg)
1845 			snprintf(isid_buf, 32, "initiator_sid=%s\n",
1846 					pr_reg->pr_reg_isid);
1847 		/*
1848 		 * Include special metadata if the pr_reg matches the
1849 		 * reservation holder.
1850 		 */
1851 		if (dev->dev_pr_res_holder == pr_reg) {
1852 			snprintf(tmp, 512, "PR_REG_START: %d"
1853 				"\ninitiator_fabric=%s\n"
1854 				"initiator_node=%s\n%s"
1855 				"sa_res_key=%llu\n"
1856 				"res_holder=1\nres_type=%02x\n"
1857 				"res_scope=%02x\nres_all_tg_pt=%d\n"
1858 				"mapped_lun=%u\n", reg_count,
1859 				tpg->se_tpg_tfo->get_fabric_name(),
1860 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1861 				pr_reg->pr_res_key, pr_reg->pr_res_type,
1862 				pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1863 				pr_reg->pr_res_mapped_lun);
1864 		} else {
1865 			snprintf(tmp, 512, "PR_REG_START: %d\n"
1866 				"initiator_fabric=%s\ninitiator_node=%s\n%s"
1867 				"sa_res_key=%llu\nres_holder=0\n"
1868 				"res_all_tg_pt=%d\nmapped_lun=%u\n",
1869 				reg_count, tpg->se_tpg_tfo->get_fabric_name(),
1870 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1871 				pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1872 				pr_reg->pr_res_mapped_lun);
1873 		}
1874 
1875 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1876 			pr_err("Unable to update renaming APTPL metadata,"
1877 			       " reallocating larger buffer\n");
1878 			ret = -EMSGSIZE;
1879 			goto out;
1880 		}
1881 		len += sprintf(buf+len, "%s", tmp);
1882 
1883 		/*
1884 		 * Include information about the associated SCSI target port.
1885 		 */
1886 		snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1887 			"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%u\nPR_REG_END:"
1888 			" %d\n", tpg->se_tpg_tfo->get_fabric_name(),
1889 			tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1890 			tpg->se_tpg_tfo->tpg_get_tag(tpg),
1891 			lun->lun_sep->sep_rtpi, lun->unpacked_lun, reg_count);
1892 
1893 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1894 			pr_err("Unable to update renaming APTPL metadata,"
1895 			       " reallocating larger buffer\n");
1896 			ret = -EMSGSIZE;
1897 			goto out;
1898 		}
1899 		len += sprintf(buf+len, "%s", tmp);
1900 		reg_count++;
1901 	}
1902 
1903 	if (!reg_count)
1904 		len += sprintf(buf+len, "No Registrations or Reservations");
1905 
1906 out:
1907 	spin_unlock(&dev->t10_pr.registration_lock);
1908 	spin_unlock(&dev->dev_reservation_lock);
1909 
1910 	return ret;
1911 }
1912 
1913 static int __core_scsi3_write_aptpl_to_file(
1914 	struct se_device *dev,
1915 	unsigned char *buf)
1916 {
1917 	struct t10_wwn *wwn = &dev->t10_wwn;
1918 	struct file *file;
1919 	int flags = O_RDWR | O_CREAT | O_TRUNC;
1920 	char path[512];
1921 	u32 pr_aptpl_buf_len;
1922 	int ret;
1923 
1924 	memset(path, 0, 512);
1925 
1926 	if (strlen(&wwn->unit_serial[0]) >= 512) {
1927 		pr_err("WWN value for struct se_device does not fit"
1928 			" into path buffer\n");
1929 		return -EMSGSIZE;
1930 	}
1931 
1932 	snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
1933 	file = filp_open(path, flags, 0600);
1934 	if (IS_ERR(file)) {
1935 		pr_err("filp_open(%s) for APTPL metadata"
1936 			" failed\n", path);
1937 		return PTR_ERR(file);
1938 	}
1939 
1940 	pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
1941 
1942 	ret = kernel_write(file, buf, pr_aptpl_buf_len, 0);
1943 
1944 	if (ret < 0)
1945 		pr_debug("Error writing APTPL metadata file: %s\n", path);
1946 	fput(file);
1947 
1948 	return (ret < 0) ? -EIO : 0;
1949 }
1950 
1951 /*
1952  * Clear the APTPL metadata if APTPL has been disabled, otherwise
1953  * write out the updated metadata to struct file for this SCSI device.
1954  */
1955 static sense_reason_t core_scsi3_update_and_write_aptpl(struct se_device *dev, bool aptpl)
1956 {
1957 	unsigned char *buf;
1958 	int rc, len = PR_APTPL_BUF_LEN;
1959 
1960 	if (!aptpl) {
1961 		char *null_buf = "No Registrations or Reservations\n";
1962 
1963 		rc = __core_scsi3_write_aptpl_to_file(dev, null_buf);
1964 		dev->t10_pr.pr_aptpl_active = 0;
1965 		pr_debug("SPC-3 PR: Set APTPL Bit Deactivated\n");
1966 
1967 		if (rc)
1968 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1969 
1970 		return 0;
1971 	}
1972 retry:
1973 	buf = vzalloc(len);
1974 	if (!buf)
1975 		return TCM_OUT_OF_RESOURCES;
1976 
1977 	rc = core_scsi3_update_aptpl_buf(dev, buf, len);
1978 	if (rc < 0) {
1979 		vfree(buf);
1980 		len *= 2;
1981 		goto retry;
1982 	}
1983 
1984 	rc = __core_scsi3_write_aptpl_to_file(dev, buf);
1985 	if (rc != 0) {
1986 		pr_err("SPC-3 PR: Could not update APTPL\n");
1987 		vfree(buf);
1988 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1989 	}
1990 	dev->t10_pr.pr_aptpl_active = 1;
1991 	vfree(buf);
1992 	pr_debug("SPC-3 PR: Set APTPL Bit Activated\n");
1993 	return 0;
1994 }
1995 
1996 static sense_reason_t
1997 core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
1998 		bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type)
1999 {
2000 	struct se_session *se_sess = cmd->se_sess;
2001 	struct se_device *dev = cmd->se_dev;
2002 	struct se_dev_entry *se_deve;
2003 	struct se_lun *se_lun = cmd->se_lun;
2004 	struct se_portal_group *se_tpg;
2005 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp;
2006 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2007 	unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2008 	sense_reason_t ret = TCM_NO_SENSE;
2009 	int pr_holder = 0, type;
2010 
2011 	if (!se_sess || !se_lun) {
2012 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2013 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2014 	}
2015 	se_tpg = se_sess->se_tpg;
2016 	se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2017 
2018 	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2019 		memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2020 		se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2021 				PR_REG_ISID_LEN);
2022 		isid_ptr = &isid_buf[0];
2023 	}
2024 	/*
2025 	 * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2026 	 */
2027 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2028 	if (!pr_reg) {
2029 		if (res_key) {
2030 			pr_warn("SPC-3 PR: Reservation Key non-zero"
2031 				" for SA REGISTER, returning CONFLICT\n");
2032 			return TCM_RESERVATION_CONFLICT;
2033 		}
2034 		/*
2035 		 * Do nothing but return GOOD status.
2036 		 */
2037 		if (!sa_res_key)
2038 			return 0;
2039 
2040 		if (!spec_i_pt) {
2041 			/*
2042 			 * Perform the Service Action REGISTER on the Initiator
2043 			 * Port Endpoint that the PRO was received from on the
2044 			 * Logical Unit of the SCSI device server.
2045 			 */
2046 			if (core_scsi3_alloc_registration(cmd->se_dev,
2047 					se_sess->se_node_acl, se_deve, isid_ptr,
2048 					sa_res_key, all_tg_pt, aptpl,
2049 					register_type, 0)) {
2050 				pr_err("Unable to allocate"
2051 					" struct t10_pr_registration\n");
2052 				return TCM_INVALID_PARAMETER_LIST;
2053 			}
2054 		} else {
2055 			/*
2056 			 * Register both the Initiator port that received
2057 			 * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2058 			 * TransportID from Parameter list and loop through
2059 			 * fabric dependent parameter list while calling
2060 			 * logic from of core_scsi3_alloc_registration() for
2061 			 * each TransportID provided SCSI Initiator Port/Device
2062 			 */
2063 			ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2064 					isid_ptr, sa_res_key, all_tg_pt, aptpl);
2065 			if (ret != 0)
2066 				return ret;
2067 		}
2068 
2069 		return core_scsi3_update_and_write_aptpl(dev, aptpl);
2070 	}
2071 
2072 	/* ok, existing registration */
2073 
2074 	if ((register_type == REGISTER) && (res_key != pr_reg->pr_res_key)) {
2075 		pr_err("SPC-3 PR REGISTER: Received"
2076 		       " res_key: 0x%016Lx does not match"
2077 		       " existing SA REGISTER res_key:"
2078 		       " 0x%016Lx\n", res_key,
2079 		       pr_reg->pr_res_key);
2080 		ret = TCM_RESERVATION_CONFLICT;
2081 		goto out;
2082 	}
2083 
2084 	if (spec_i_pt) {
2085 		pr_err("SPC-3 PR REGISTER: SPEC_I_PT"
2086 			" set on a registered nexus\n");
2087 		ret = TCM_INVALID_PARAMETER_LIST;
2088 		goto out;
2089 	}
2090 
2091 	/*
2092 	 * An existing ALL_TG_PT=1 registration being released
2093 	 * must also set ALL_TG_PT=1 in the incoming PROUT.
2094 	 */
2095 	if (pr_reg->pr_reg_all_tg_pt && !all_tg_pt) {
2096 		pr_err("SPC-3 PR REGISTER: ALL_TG_PT=1"
2097 			" registration exists, but ALL_TG_PT=1 bit not"
2098 			" present in received PROUT\n");
2099 		ret = TCM_INVALID_CDB_FIELD;
2100 		goto out;
2101 	}
2102 
2103 	/*
2104 	 * sa_res_key=1 Change Reservation Key for registered I_T Nexus.
2105 	 */
2106 	if (sa_res_key) {
2107 		/*
2108 		 * Increment PRgeneration counter for struct se_device"
2109 		 * upon a successful REGISTER, see spc4r17 section 6.3.2
2110 		 * READ_KEYS service action.
2111 		 */
2112 		pr_reg->pr_res_generation = core_scsi3_pr_generation(cmd->se_dev);
2113 		pr_reg->pr_res_key = sa_res_key;
2114 		pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2115 			 " Key for %s to: 0x%016Lx PRgeneration:"
2116 			 " 0x%08x\n", cmd->se_tfo->get_fabric_name(),
2117 			 (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ? "_AND_IGNORE_EXISTING_KEY" : "",
2118 			 pr_reg->pr_reg_nacl->initiatorname,
2119 			 pr_reg->pr_res_key, pr_reg->pr_res_generation);
2120 
2121 	} else {
2122 		/*
2123 		 * sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
2124 		 */
2125 		type = pr_reg->pr_res_type;
2126 		pr_holder = core_scsi3_check_implicit_release(cmd->se_dev,
2127 							      pr_reg);
2128 		if (pr_holder < 0) {
2129 			ret = TCM_RESERVATION_CONFLICT;
2130 			goto out;
2131 		}
2132 
2133 		spin_lock(&pr_tmpl->registration_lock);
2134 		/*
2135 		 * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2136 		 * and matching pr_res_key.
2137 		 */
2138 		if (pr_reg->pr_reg_all_tg_pt) {
2139 			list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2140 					&pr_tmpl->registration_list,
2141 					pr_reg_list) {
2142 
2143 				if (!pr_reg_p->pr_reg_all_tg_pt)
2144 					continue;
2145 				if (pr_reg_p->pr_res_key != res_key)
2146 					continue;
2147 				if (pr_reg == pr_reg_p)
2148 					continue;
2149 				if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2150 					   pr_reg_p->pr_reg_nacl->initiatorname))
2151 					continue;
2152 
2153 				__core_scsi3_free_registration(dev,
2154 						pr_reg_p, NULL, 0);
2155 			}
2156 		}
2157 
2158 		/*
2159 		 * Release the calling I_T Nexus registration now..
2160 		 */
2161 		__core_scsi3_free_registration(cmd->se_dev, pr_reg, NULL, 1);
2162 		pr_reg = NULL;
2163 
2164 		/*
2165 		 * From spc4r17, section 5.7.11.3 Unregistering
2166 		 *
2167 		 * If the persistent reservation is a registrants only
2168 		 * type, the device server shall establish a unit
2169 		 * attention condition for the initiator port associated
2170 		 * with every registered I_T nexus except for the I_T
2171 		 * nexus on which the PERSISTENT RESERVE OUT command was
2172 		 * received, with the additional sense code set to
2173 		 * RESERVATIONS RELEASED.
2174 		 */
2175 		if (pr_holder &&
2176 		    (type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY ||
2177 		     type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY)) {
2178 			list_for_each_entry(pr_reg_p,
2179 					&pr_tmpl->registration_list,
2180 					pr_reg_list) {
2181 
2182 				core_scsi3_ua_allocate(
2183 					pr_reg_p->pr_reg_nacl,
2184 					pr_reg_p->pr_res_mapped_lun,
2185 					0x2A,
2186 					ASCQ_2AH_RESERVATIONS_RELEASED);
2187 			}
2188 		}
2189 
2190 		spin_unlock(&pr_tmpl->registration_lock);
2191 	}
2192 
2193 	ret = core_scsi3_update_and_write_aptpl(dev, aptpl);
2194 
2195 out:
2196 	if (pr_reg)
2197 		core_scsi3_put_pr_reg(pr_reg);
2198 	return ret;
2199 }
2200 
2201 unsigned char *core_scsi3_pr_dump_type(int type)
2202 {
2203 	switch (type) {
2204 	case PR_TYPE_WRITE_EXCLUSIVE:
2205 		return "Write Exclusive Access";
2206 	case PR_TYPE_EXCLUSIVE_ACCESS:
2207 		return "Exclusive Access";
2208 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2209 		return "Write Exclusive Access, Registrants Only";
2210 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2211 		return "Exclusive Access, Registrants Only";
2212 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2213 		return "Write Exclusive Access, All Registrants";
2214 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2215 		return "Exclusive Access, All Registrants";
2216 	default:
2217 		break;
2218 	}
2219 
2220 	return "Unknown SPC-3 PR Type";
2221 }
2222 
2223 static sense_reason_t
2224 core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
2225 {
2226 	struct se_device *dev = cmd->se_dev;
2227 	struct se_session *se_sess = cmd->se_sess;
2228 	struct se_lun *se_lun = cmd->se_lun;
2229 	struct t10_pr_registration *pr_reg, *pr_res_holder;
2230 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2231 	char i_buf[PR_REG_ISID_ID_LEN];
2232 	sense_reason_t ret;
2233 
2234 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2235 
2236 	if (!se_sess || !se_lun) {
2237 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2238 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2239 	}
2240 	/*
2241 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2242 	 */
2243 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2244 				se_sess);
2245 	if (!pr_reg) {
2246 		pr_err("SPC-3 PR: Unable to locate"
2247 			" PR_REGISTERED *pr_reg for RESERVE\n");
2248 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2249 	}
2250 	/*
2251 	 * From spc4r17 Section 5.7.9: Reserving:
2252 	 *
2253 	 * An application client creates a persistent reservation by issuing
2254 	 * a PERSISTENT RESERVE OUT command with RESERVE service action through
2255 	 * a registered I_T nexus with the following parameters:
2256 	 *    a) RESERVATION KEY set to the value of the reservation key that is
2257 	 * 	 registered with the logical unit for the I_T nexus; and
2258 	 */
2259 	if (res_key != pr_reg->pr_res_key) {
2260 		pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2261 			" does not match existing SA REGISTER res_key:"
2262 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2263 		ret = TCM_RESERVATION_CONFLICT;
2264 		goto out_put_pr_reg;
2265 	}
2266 	/*
2267 	 * From spc4r17 Section 5.7.9: Reserving:
2268 	 *
2269 	 * From above:
2270 	 *  b) TYPE field and SCOPE field set to the persistent reservation
2271 	 *     being created.
2272 	 *
2273 	 * Only one persistent reservation is allowed at a time per logical unit
2274 	 * and that persistent reservation has a scope of LU_SCOPE.
2275 	 */
2276 	if (scope != PR_SCOPE_LU_SCOPE) {
2277 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2278 		ret = TCM_INVALID_PARAMETER_LIST;
2279 		goto out_put_pr_reg;
2280 	}
2281 	/*
2282 	 * See if we have an existing PR reservation holder pointer at
2283 	 * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2284 	 * *pr_res_holder.
2285 	 */
2286 	spin_lock(&dev->dev_reservation_lock);
2287 	pr_res_holder = dev->dev_pr_res_holder;
2288 	if (pr_res_holder) {
2289 		/*
2290 		 * From spc4r17 Section 5.7.9: Reserving:
2291 		 *
2292 		 * If the device server receives a PERSISTENT RESERVE OUT
2293 		 * command from an I_T nexus other than a persistent reservation
2294 		 * holder (see 5.7.10) that attempts to create a persistent
2295 		 * reservation when a persistent reservation already exists for
2296 		 * the logical unit, then the command shall be completed with
2297 		 * RESERVATION CONFLICT status.
2298 		 */
2299 		if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2300 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2301 			pr_err("SPC-3 PR: Attempted RESERVE from"
2302 				" [%s]: %s while reservation already held by"
2303 				" [%s]: %s, returning RESERVATION_CONFLICT\n",
2304 				cmd->se_tfo->get_fabric_name(),
2305 				se_sess->se_node_acl->initiatorname,
2306 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2307 				pr_res_holder->pr_reg_nacl->initiatorname);
2308 
2309 			spin_unlock(&dev->dev_reservation_lock);
2310 			ret = TCM_RESERVATION_CONFLICT;
2311 			goto out_put_pr_reg;
2312 		}
2313 		/*
2314 		 * From spc4r17 Section 5.7.9: Reserving:
2315 		 *
2316 		 * If a persistent reservation holder attempts to modify the
2317 		 * type or scope of an existing persistent reservation, the
2318 		 * command shall be completed with RESERVATION CONFLICT status.
2319 		 */
2320 		if ((pr_res_holder->pr_res_type != type) ||
2321 		    (pr_res_holder->pr_res_scope != scope)) {
2322 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2323 			pr_err("SPC-3 PR: Attempted RESERVE from"
2324 				" [%s]: %s trying to change TYPE and/or SCOPE,"
2325 				" while reservation already held by [%s]: %s,"
2326 				" returning RESERVATION_CONFLICT\n",
2327 				cmd->se_tfo->get_fabric_name(),
2328 				se_sess->se_node_acl->initiatorname,
2329 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2330 				pr_res_holder->pr_reg_nacl->initiatorname);
2331 
2332 			spin_unlock(&dev->dev_reservation_lock);
2333 			ret = TCM_RESERVATION_CONFLICT;
2334 			goto out_put_pr_reg;
2335 		}
2336 		/*
2337 		 * From spc4r17 Section 5.7.9: Reserving:
2338 		 *
2339 		 * If the device server receives a PERSISTENT RESERVE OUT
2340 		 * command with RESERVE service action where the TYPE field and
2341 		 * the SCOPE field contain the same values as the existing type
2342 		 * and scope from a persistent reservation holder, it shall not
2343 		 * make any change to the existing persistent reservation and
2344 		 * shall completethe command with GOOD status.
2345 		 */
2346 		spin_unlock(&dev->dev_reservation_lock);
2347 		ret = 0;
2348 		goto out_put_pr_reg;
2349 	}
2350 	/*
2351 	 * Otherwise, our *pr_reg becomes the PR reservation holder for said
2352 	 * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2353 	 */
2354 	pr_reg->pr_res_scope = scope;
2355 	pr_reg->pr_res_type = type;
2356 	pr_reg->pr_res_holder = 1;
2357 	dev->dev_pr_res_holder = pr_reg;
2358 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2359 
2360 	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2361 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2362 		cmd->se_tfo->get_fabric_name(), core_scsi3_pr_dump_type(type),
2363 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2364 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2365 			cmd->se_tfo->get_fabric_name(),
2366 			se_sess->se_node_acl->initiatorname,
2367 			i_buf);
2368 	spin_unlock(&dev->dev_reservation_lock);
2369 
2370 	if (pr_tmpl->pr_aptpl_active)
2371 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2372 
2373 	ret = 0;
2374 out_put_pr_reg:
2375 	core_scsi3_put_pr_reg(pr_reg);
2376 	return ret;
2377 }
2378 
2379 static sense_reason_t
2380 core_scsi3_emulate_pro_reserve(struct se_cmd *cmd, int type, int scope,
2381 		u64 res_key)
2382 {
2383 	switch (type) {
2384 	case PR_TYPE_WRITE_EXCLUSIVE:
2385 	case PR_TYPE_EXCLUSIVE_ACCESS:
2386 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2387 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2388 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2389 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2390 		return core_scsi3_pro_reserve(cmd, type, scope, res_key);
2391 	default:
2392 		pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2393 			" 0x%02x\n", type);
2394 		return TCM_INVALID_CDB_FIELD;
2395 	}
2396 }
2397 
2398 /*
2399  * Called with struct se_device->dev_reservation_lock held.
2400  */
2401 static void __core_scsi3_complete_pro_release(
2402 	struct se_device *dev,
2403 	struct se_node_acl *se_nacl,
2404 	struct t10_pr_registration *pr_reg,
2405 	int explicit,
2406 	int unreg)
2407 {
2408 	const struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2409 	char i_buf[PR_REG_ISID_ID_LEN];
2410 	int pr_res_type = 0, pr_res_scope = 0;
2411 
2412 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2413 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2414 	/*
2415 	 * Go ahead and release the current PR reservation holder.
2416 	 * If an All Registrants reservation is currently active and
2417 	 * a unregister operation is requested, replace the current
2418 	 * dev_pr_res_holder with another active registration.
2419 	 */
2420 	if (dev->dev_pr_res_holder) {
2421 		pr_res_type = dev->dev_pr_res_holder->pr_res_type;
2422 		pr_res_scope = dev->dev_pr_res_holder->pr_res_scope;
2423 		dev->dev_pr_res_holder->pr_res_type = 0;
2424 		dev->dev_pr_res_holder->pr_res_scope = 0;
2425 		dev->dev_pr_res_holder->pr_res_holder = 0;
2426 		dev->dev_pr_res_holder = NULL;
2427 	}
2428 	if (!unreg)
2429 		goto out;
2430 
2431 	spin_lock(&dev->t10_pr.registration_lock);
2432 	list_del_init(&pr_reg->pr_reg_list);
2433 	/*
2434 	 * If the I_T nexus is a reservation holder, the persistent reservation
2435 	 * is of an all registrants type, and the I_T nexus is the last remaining
2436 	 * registered I_T nexus, then the device server shall also release the
2437 	 * persistent reservation.
2438 	 */
2439 	if (!list_empty(&dev->t10_pr.registration_list) &&
2440 	    ((pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2441 	     (pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))) {
2442 		dev->dev_pr_res_holder =
2443 			list_entry(dev->t10_pr.registration_list.next,
2444 				   struct t10_pr_registration, pr_reg_list);
2445 		dev->dev_pr_res_holder->pr_res_type = pr_res_type;
2446 		dev->dev_pr_res_holder->pr_res_scope = pr_res_scope;
2447 		dev->dev_pr_res_holder->pr_res_holder = 1;
2448 	}
2449 	spin_unlock(&dev->t10_pr.registration_lock);
2450 out:
2451 	if (!dev->dev_pr_res_holder) {
2452 		pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2453 			" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2454 			tfo->get_fabric_name(), (explicit) ? "explicit" :
2455 			"implicit", core_scsi3_pr_dump_type(pr_res_type),
2456 			(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2457 	}
2458 	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2459 		tfo->get_fabric_name(), se_nacl->initiatorname,
2460 		i_buf);
2461 	/*
2462 	 * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2463 	 */
2464 	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2465 }
2466 
2467 static sense_reason_t
2468 core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
2469 		u64 res_key)
2470 {
2471 	struct se_device *dev = cmd->se_dev;
2472 	struct se_session *se_sess = cmd->se_sess;
2473 	struct se_lun *se_lun = cmd->se_lun;
2474 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2475 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2476 	sense_reason_t ret = 0;
2477 
2478 	if (!se_sess || !se_lun) {
2479 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2480 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2481 	}
2482 	/*
2483 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2484 	 */
2485 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2486 	if (!pr_reg) {
2487 		pr_err("SPC-3 PR: Unable to locate"
2488 			" PR_REGISTERED *pr_reg for RELEASE\n");
2489 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2490 	}
2491 	/*
2492 	 * From spc4r17 Section 5.7.11.2 Releasing:
2493 	 *
2494 	 * If there is no persistent reservation or in response to a persistent
2495 	 * reservation release request from a registered I_T nexus that is not a
2496 	 * persistent reservation holder (see 5.7.10), the device server shall
2497 	 * do the following:
2498 	 *
2499 	 *     a) Not release the persistent reservation, if any;
2500 	 *     b) Not remove any registrations; and
2501 	 *     c) Complete the command with GOOD status.
2502 	 */
2503 	spin_lock(&dev->dev_reservation_lock);
2504 	pr_res_holder = dev->dev_pr_res_holder;
2505 	if (!pr_res_holder) {
2506 		/*
2507 		 * No persistent reservation, return GOOD status.
2508 		 */
2509 		spin_unlock(&dev->dev_reservation_lock);
2510 		goto out_put_pr_reg;
2511 	}
2512 
2513 	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2514 		/*
2515 		 * Release request from a registered I_T nexus that is not a
2516 		 * persistent reservation holder. return GOOD status.
2517 		 */
2518 		spin_unlock(&dev->dev_reservation_lock);
2519 		goto out_put_pr_reg;
2520 	}
2521 
2522 	/*
2523 	 * From spc4r17 Section 5.7.11.2 Releasing:
2524 	 *
2525 	 * Only the persistent reservation holder (see 5.7.10) is allowed to
2526 	 * release a persistent reservation.
2527 	 *
2528 	 * An application client releases the persistent reservation by issuing
2529 	 * a PERSISTENT RESERVE OUT command with RELEASE service action through
2530 	 * an I_T nexus that is a persistent reservation holder with the
2531 	 * following parameters:
2532 	 *
2533 	 *     a) RESERVATION KEY field set to the value of the reservation key
2534 	 *	  that is registered with the logical unit for the I_T nexus;
2535 	 */
2536 	if (res_key != pr_reg->pr_res_key) {
2537 		pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2538 			" does not match existing SA REGISTER res_key:"
2539 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2540 		spin_unlock(&dev->dev_reservation_lock);
2541 		ret = TCM_RESERVATION_CONFLICT;
2542 		goto out_put_pr_reg;
2543 	}
2544 	/*
2545 	 * From spc4r17 Section 5.7.11.2 Releasing and above:
2546 	 *
2547 	 * b) TYPE field and SCOPE field set to match the persistent
2548 	 *    reservation being released.
2549 	 */
2550 	if ((pr_res_holder->pr_res_type != type) ||
2551 	    (pr_res_holder->pr_res_scope != scope)) {
2552 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2553 		pr_err("SPC-3 PR RELEASE: Attempted to release"
2554 			" reservation from [%s]: %s with different TYPE "
2555 			"and/or SCOPE  while reservation already held by"
2556 			" [%s]: %s, returning RESERVATION_CONFLICT\n",
2557 			cmd->se_tfo->get_fabric_name(),
2558 			se_sess->se_node_acl->initiatorname,
2559 			pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2560 			pr_res_holder->pr_reg_nacl->initiatorname);
2561 
2562 		spin_unlock(&dev->dev_reservation_lock);
2563 		ret = TCM_RESERVATION_CONFLICT;
2564 		goto out_put_pr_reg;
2565 	}
2566 	/*
2567 	 * In response to a persistent reservation release request from the
2568 	 * persistent reservation holder the device server shall perform a
2569 	 * release by doing the following as an uninterrupted series of actions:
2570 	 * a) Release the persistent reservation;
2571 	 * b) Not remove any registration(s);
2572 	 * c) If the released persistent reservation is a registrants only type
2573 	 * or all registrants type persistent reservation,
2574 	 *    the device server shall establish a unit attention condition for
2575 	 *    the initiator port associated with every regis-
2576 	 *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2577 	 *    RESERVE OUT command with RELEASE service action was received,
2578 	 *    with the additional sense code set to RESERVATIONS RELEASED; and
2579 	 * d) If the persistent reservation is of any other type, the device
2580 	 *    server shall not establish a unit attention condition.
2581 	 */
2582 	__core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2583 					  pr_reg, 1, 0);
2584 
2585 	spin_unlock(&dev->dev_reservation_lock);
2586 
2587 	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2588 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2589 	    (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2590 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2591 		/*
2592 		 * If no UNIT ATTENTION conditions will be established for
2593 		 * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2594 		 * go ahead and check for APTPL=1 update+write below
2595 		 */
2596 		goto write_aptpl;
2597 	}
2598 
2599 	spin_lock(&pr_tmpl->registration_lock);
2600 	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2601 			pr_reg_list) {
2602 		/*
2603 		 * Do not establish a UNIT ATTENTION condition
2604 		 * for the calling I_T Nexus
2605 		 */
2606 		if (pr_reg_p == pr_reg)
2607 			continue;
2608 
2609 		core_scsi3_ua_allocate(pr_reg_p->pr_reg_nacl,
2610 				pr_reg_p->pr_res_mapped_lun,
2611 				0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2612 	}
2613 	spin_unlock(&pr_tmpl->registration_lock);
2614 
2615 write_aptpl:
2616 	if (pr_tmpl->pr_aptpl_active)
2617 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2618 
2619 out_put_pr_reg:
2620 	core_scsi3_put_pr_reg(pr_reg);
2621 	return ret;
2622 }
2623 
2624 static sense_reason_t
2625 core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
2626 {
2627 	struct se_device *dev = cmd->se_dev;
2628 	struct se_node_acl *pr_reg_nacl;
2629 	struct se_session *se_sess = cmd->se_sess;
2630 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2631 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2632 	u32 pr_res_mapped_lun = 0;
2633 	int calling_it_nexus = 0;
2634 	/*
2635 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2636 	 */
2637 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2638 			se_sess->se_node_acl, se_sess);
2639 	if (!pr_reg_n) {
2640 		pr_err("SPC-3 PR: Unable to locate"
2641 			" PR_REGISTERED *pr_reg for CLEAR\n");
2642 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2643 	}
2644 	/*
2645 	 * From spc4r17 section 5.7.11.6, Clearing:
2646 	 *
2647 	 * Any application client may release the persistent reservation and
2648 	 * remove all registrations from a device server by issuing a
2649 	 * PERSISTENT RESERVE OUT command with CLEAR service action through a
2650 	 * registered I_T nexus with the following parameter:
2651 	 *
2652 	 *	a) RESERVATION KEY field set to the value of the reservation key
2653 	 * 	   that is registered with the logical unit for the I_T nexus.
2654 	 */
2655 	if (res_key != pr_reg_n->pr_res_key) {
2656 		pr_err("SPC-3 PR REGISTER: Received"
2657 			" res_key: 0x%016Lx does not match"
2658 			" existing SA REGISTER res_key:"
2659 			" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2660 		core_scsi3_put_pr_reg(pr_reg_n);
2661 		return TCM_RESERVATION_CONFLICT;
2662 	}
2663 	/*
2664 	 * a) Release the persistent reservation, if any;
2665 	 */
2666 	spin_lock(&dev->dev_reservation_lock);
2667 	pr_res_holder = dev->dev_pr_res_holder;
2668 	if (pr_res_holder) {
2669 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2670 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
2671 						  pr_res_holder, 0, 0);
2672 	}
2673 	spin_unlock(&dev->dev_reservation_lock);
2674 	/*
2675 	 * b) Remove all registration(s) (see spc4r17 5.7.7);
2676 	 */
2677 	spin_lock(&pr_tmpl->registration_lock);
2678 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2679 			&pr_tmpl->registration_list, pr_reg_list) {
2680 
2681 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2682 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2683 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2684 		__core_scsi3_free_registration(dev, pr_reg, NULL,
2685 					calling_it_nexus);
2686 		/*
2687 		 * e) Establish a unit attention condition for the initiator
2688 		 *    port associated with every registered I_T nexus other
2689 		 *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2690 		 *    command with CLEAR service action was received, with the
2691 		 *    additional sense code set to RESERVATIONS PREEMPTED.
2692 		 */
2693 		if (!calling_it_nexus)
2694 			core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun,
2695 				0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2696 	}
2697 	spin_unlock(&pr_tmpl->registration_lock);
2698 
2699 	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2700 		cmd->se_tfo->get_fabric_name());
2701 
2702 	core_scsi3_update_and_write_aptpl(cmd->se_dev, false);
2703 
2704 	core_scsi3_pr_generation(dev);
2705 	return 0;
2706 }
2707 
2708 /*
2709  * Called with struct se_device->dev_reservation_lock held.
2710  */
2711 static void __core_scsi3_complete_pro_preempt(
2712 	struct se_device *dev,
2713 	struct t10_pr_registration *pr_reg,
2714 	struct list_head *preempt_and_abort_list,
2715 	int type,
2716 	int scope,
2717 	enum preempt_type preempt_type)
2718 {
2719 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2720 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2721 	char i_buf[PR_REG_ISID_ID_LEN];
2722 
2723 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2724 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2725 	/*
2726 	 * Do an implicit RELEASE of the existing reservation.
2727 	 */
2728 	if (dev->dev_pr_res_holder)
2729 		__core_scsi3_complete_pro_release(dev, nacl,
2730 						  dev->dev_pr_res_holder, 0, 0);
2731 
2732 	dev->dev_pr_res_holder = pr_reg;
2733 	pr_reg->pr_res_holder = 1;
2734 	pr_reg->pr_res_type = type;
2735 	pr_reg->pr_res_scope = scope;
2736 
2737 	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2738 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2739 		tfo->get_fabric_name(), (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2740 		core_scsi3_pr_dump_type(type),
2741 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2742 	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2743 		tfo->get_fabric_name(), (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2744 		nacl->initiatorname, i_buf);
2745 	/*
2746 	 * For PREEMPT_AND_ABORT, add the preempting reservation's
2747 	 * struct t10_pr_registration to the list that will be compared
2748 	 * against received CDBs..
2749 	 */
2750 	if (preempt_and_abort_list)
2751 		list_add_tail(&pr_reg->pr_reg_abort_list,
2752 				preempt_and_abort_list);
2753 }
2754 
2755 static void core_scsi3_release_preempt_and_abort(
2756 	struct list_head *preempt_and_abort_list,
2757 	struct t10_pr_registration *pr_reg_holder)
2758 {
2759 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2760 
2761 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2762 				pr_reg_abort_list) {
2763 
2764 		list_del(&pr_reg->pr_reg_abort_list);
2765 		if (pr_reg_holder == pr_reg)
2766 			continue;
2767 		if (pr_reg->pr_res_holder) {
2768 			pr_warn("pr_reg->pr_res_holder still set\n");
2769 			continue;
2770 		}
2771 
2772 		pr_reg->pr_reg_deve = NULL;
2773 		pr_reg->pr_reg_nacl = NULL;
2774 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
2775 	}
2776 }
2777 
2778 static sense_reason_t
2779 core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
2780 		u64 sa_res_key, enum preempt_type preempt_type)
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 	LIST_HEAD(preempt_and_abort_list);
2786 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2787 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2788 	u32 pr_res_mapped_lun = 0;
2789 	int all_reg = 0, calling_it_nexus = 0;
2790 	bool sa_res_key_unmatched = sa_res_key != 0;
2791 	int prh_type = 0, prh_scope = 0;
2792 
2793 	if (!se_sess)
2794 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2795 
2796 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2797 				se_sess);
2798 	if (!pr_reg_n) {
2799 		pr_err("SPC-3 PR: Unable to locate"
2800 			" PR_REGISTERED *pr_reg for PREEMPT%s\n",
2801 			(preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "");
2802 		return TCM_RESERVATION_CONFLICT;
2803 	}
2804 	if (pr_reg_n->pr_res_key != res_key) {
2805 		core_scsi3_put_pr_reg(pr_reg_n);
2806 		return TCM_RESERVATION_CONFLICT;
2807 	}
2808 	if (scope != PR_SCOPE_LU_SCOPE) {
2809 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2810 		core_scsi3_put_pr_reg(pr_reg_n);
2811 		return TCM_INVALID_PARAMETER_LIST;
2812 	}
2813 
2814 	spin_lock(&dev->dev_reservation_lock);
2815 	pr_res_holder = dev->dev_pr_res_holder;
2816 	if (pr_res_holder &&
2817 	   ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2818 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
2819 		all_reg = 1;
2820 
2821 	if (!all_reg && !sa_res_key) {
2822 		spin_unlock(&dev->dev_reservation_lock);
2823 		core_scsi3_put_pr_reg(pr_reg_n);
2824 		return TCM_INVALID_PARAMETER_LIST;
2825 	}
2826 	/*
2827 	 * From spc4r17, section 5.7.11.4.4 Removing Registrations:
2828 	 *
2829 	 * If the SERVICE ACTION RESERVATION KEY field does not identify a
2830 	 * persistent reservation holder or there is no persistent reservation
2831 	 * holder (i.e., there is no persistent reservation), then the device
2832 	 * server shall perform a preempt by doing the following in an
2833 	 * uninterrupted series of actions. (See below..)
2834 	 */
2835 	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
2836 		/*
2837 		 * No existing or SA Reservation Key matching reservations..
2838 		 *
2839 		 * PROUT SA PREEMPT with All Registrant type reservations are
2840 		 * allowed to be processed without a matching SA Reservation Key
2841 		 */
2842 		spin_lock(&pr_tmpl->registration_lock);
2843 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2844 				&pr_tmpl->registration_list, pr_reg_list) {
2845 			/*
2846 			 * Removing of registrations in non all registrants
2847 			 * type reservations without a matching SA reservation
2848 			 * key.
2849 			 *
2850 			 * a) Remove the registrations for all I_T nexuses
2851 			 *    specified by the SERVICE ACTION RESERVATION KEY
2852 			 *    field;
2853 			 * b) Ignore the contents of the SCOPE and TYPE fields;
2854 			 * c) Process tasks as defined in 5.7.1; and
2855 			 * d) Establish a unit attention condition for the
2856 			 *    initiator port associated with every I_T nexus
2857 			 *    that lost its registration other than the I_T
2858 			 *    nexus on which the PERSISTENT RESERVE OUT command
2859 			 *    was received, with the additional sense code set
2860 			 *    to REGISTRATIONS PREEMPTED.
2861 			 */
2862 			if (!all_reg) {
2863 				if (pr_reg->pr_res_key != sa_res_key)
2864 					continue;
2865 				sa_res_key_unmatched = false;
2866 
2867 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2868 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2869 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2870 				__core_scsi3_free_registration(dev, pr_reg,
2871 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2872 						NULL, calling_it_nexus);
2873 			} else {
2874 				/*
2875 				 * Case for any existing all registrants type
2876 				 * reservation, follow logic in spc4r17 section
2877 				 * 5.7.11.4 Preempting, Table 52 and Figure 7.
2878 				 *
2879 				 * For a ZERO SA Reservation key, release
2880 				 * all other registrations and do an implicit
2881 				 * release of active persistent reservation.
2882 				 *
2883 				 * For a non-ZERO SA Reservation key, only
2884 				 * release the matching reservation key from
2885 				 * registrations.
2886 				 */
2887 				if ((sa_res_key) &&
2888 				     (pr_reg->pr_res_key != sa_res_key))
2889 					continue;
2890 				sa_res_key_unmatched = false;
2891 
2892 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2893 				if (calling_it_nexus)
2894 					continue;
2895 
2896 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2897 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2898 				__core_scsi3_free_registration(dev, pr_reg,
2899 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2900 						NULL, 0);
2901 			}
2902 			if (!calling_it_nexus)
2903 				core_scsi3_ua_allocate(pr_reg_nacl,
2904 					pr_res_mapped_lun, 0x2A,
2905 					ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2906 		}
2907 		spin_unlock(&pr_tmpl->registration_lock);
2908 		/*
2909 		 * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
2910 		 * a PREEMPT AND ABORT service action sets the SERVICE ACTION
2911 		 * RESERVATION KEY field to a value that does not match any
2912 		 * registered reservation key, then the device server shall
2913 		 * complete the command with RESERVATION CONFLICT status.
2914 		 */
2915 		if (sa_res_key_unmatched) {
2916 			spin_unlock(&dev->dev_reservation_lock);
2917 			core_scsi3_put_pr_reg(pr_reg_n);
2918 			return TCM_RESERVATION_CONFLICT;
2919 		}
2920 		/*
2921 		 * For an existing all registrants type reservation
2922 		 * with a zero SA rservation key, preempt the existing
2923 		 * reservation with the new PR type and scope.
2924 		 */
2925 		if (pr_res_holder && all_reg && !(sa_res_key)) {
2926 			__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
2927 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2928 				type, scope, preempt_type);
2929 
2930 			if (preempt_type == PREEMPT_AND_ABORT)
2931 				core_scsi3_release_preempt_and_abort(
2932 					&preempt_and_abort_list, pr_reg_n);
2933 		}
2934 		spin_unlock(&dev->dev_reservation_lock);
2935 
2936 		if (pr_tmpl->pr_aptpl_active)
2937 			core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2938 
2939 		core_scsi3_put_pr_reg(pr_reg_n);
2940 		core_scsi3_pr_generation(cmd->se_dev);
2941 		return 0;
2942 	}
2943 	/*
2944 	 * The PREEMPTing SA reservation key matches that of the
2945 	 * existing persistent reservation, first, we check if
2946 	 * we are preempting our own reservation.
2947 	 * From spc4r17, section 5.7.11.4.3 Preempting
2948 	 * persistent reservations and registration handling
2949 	 *
2950 	 * If an all registrants persistent reservation is not
2951 	 * present, it is not an error for the persistent
2952 	 * reservation holder to preempt itself (i.e., a
2953 	 * PERSISTENT RESERVE OUT with a PREEMPT service action
2954 	 * or a PREEMPT AND ABORT service action with the
2955 	 * SERVICE ACTION RESERVATION KEY value equal to the
2956 	 * persistent reservation holder's reservation key that
2957 	 * is received from the persistent reservation holder).
2958 	 * In that case, the device server shall establish the
2959 	 * new persistent reservation and maintain the
2960 	 * registration.
2961 	 */
2962 	prh_type = pr_res_holder->pr_res_type;
2963 	prh_scope = pr_res_holder->pr_res_scope;
2964 	/*
2965 	 * If the SERVICE ACTION RESERVATION KEY field identifies a
2966 	 * persistent reservation holder (see 5.7.10), the device
2967 	 * server shall perform a preempt by doing the following as
2968 	 * an uninterrupted series of actions:
2969 	 *
2970 	 * a) Release the persistent reservation for the holder
2971 	 *    identified by the SERVICE ACTION RESERVATION KEY field;
2972 	 */
2973 	if (pr_reg_n != pr_res_holder)
2974 		__core_scsi3_complete_pro_release(dev,
2975 						  pr_res_holder->pr_reg_nacl,
2976 						  dev->dev_pr_res_holder, 0, 0);
2977 	/*
2978 	 * b) Remove the registrations for all I_T nexuses identified
2979 	 *    by the SERVICE ACTION RESERVATION KEY field, except the
2980 	 *    I_T nexus that is being used for the PERSISTENT RESERVE
2981 	 *    OUT command. If an all registrants persistent reservation
2982 	 *    is present and the SERVICE ACTION RESERVATION KEY field
2983 	 *    is set to zero, then all registrations shall be removed
2984 	 *    except for that of the I_T nexus that is being used for
2985 	 *    the PERSISTENT RESERVE OUT command;
2986 	 */
2987 	spin_lock(&pr_tmpl->registration_lock);
2988 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2989 			&pr_tmpl->registration_list, pr_reg_list) {
2990 
2991 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2992 		if (calling_it_nexus)
2993 			continue;
2994 
2995 		if (pr_reg->pr_res_key != sa_res_key)
2996 			continue;
2997 
2998 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2999 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3000 		__core_scsi3_free_registration(dev, pr_reg,
3001 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3002 				calling_it_nexus);
3003 		/*
3004 		 * e) Establish a unit attention condition for the initiator
3005 		 *    port associated with every I_T nexus that lost its
3006 		 *    persistent reservation and/or registration, with the
3007 		 *    additional sense code set to REGISTRATIONS PREEMPTED;
3008 		 */
3009 		core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3010 				ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3011 	}
3012 	spin_unlock(&pr_tmpl->registration_lock);
3013 	/*
3014 	 * c) Establish a persistent reservation for the preempting
3015 	 *    I_T nexus using the contents of the SCOPE and TYPE fields;
3016 	 */
3017 	__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3018 			(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3019 			type, scope, preempt_type);
3020 	/*
3021 	 * d) Process tasks as defined in 5.7.1;
3022 	 * e) See above..
3023 	 * f) If the type or scope has changed, then for every I_T nexus
3024 	 *    whose reservation key was not removed, except for the I_T
3025 	 *    nexus on which the PERSISTENT RESERVE OUT command was
3026 	 *    received, the device server shall establish a unit
3027 	 *    attention condition for the initiator port associated with
3028 	 *    that I_T nexus, with the additional sense code set to
3029 	 *    RESERVATIONS RELEASED. If the type or scope have not
3030 	 *    changed, then no unit attention condition(s) shall be
3031 	 *    established for this reason.
3032 	 */
3033 	if ((prh_type != type) || (prh_scope != scope)) {
3034 		spin_lock(&pr_tmpl->registration_lock);
3035 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3036 				&pr_tmpl->registration_list, pr_reg_list) {
3037 
3038 			calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3039 			if (calling_it_nexus)
3040 				continue;
3041 
3042 			core_scsi3_ua_allocate(pr_reg->pr_reg_nacl,
3043 					pr_reg->pr_res_mapped_lun, 0x2A,
3044 					ASCQ_2AH_RESERVATIONS_RELEASED);
3045 		}
3046 		spin_unlock(&pr_tmpl->registration_lock);
3047 	}
3048 	spin_unlock(&dev->dev_reservation_lock);
3049 	/*
3050 	 * Call LUN_RESET logic upon list of struct t10_pr_registration,
3051 	 * All received CDBs for the matching existing reservation and
3052 	 * registrations undergo ABORT_TASK logic.
3053 	 *
3054 	 * From there, core_scsi3_release_preempt_and_abort() will
3055 	 * release every registration in the list (which have already
3056 	 * been removed from the primary pr_reg list), except the
3057 	 * new persistent reservation holder, the calling Initiator Port.
3058 	 */
3059 	if (preempt_type == PREEMPT_AND_ABORT) {
3060 		core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3061 		core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3062 						pr_reg_n);
3063 	}
3064 
3065 	if (pr_tmpl->pr_aptpl_active)
3066 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
3067 
3068 	core_scsi3_put_pr_reg(pr_reg_n);
3069 	core_scsi3_pr_generation(cmd->se_dev);
3070 	return 0;
3071 }
3072 
3073 static sense_reason_t
3074 core_scsi3_emulate_pro_preempt(struct se_cmd *cmd, int type, int scope,
3075 		u64 res_key, u64 sa_res_key, enum preempt_type preempt_type)
3076 {
3077 	switch (type) {
3078 	case PR_TYPE_WRITE_EXCLUSIVE:
3079 	case PR_TYPE_EXCLUSIVE_ACCESS:
3080 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3081 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3082 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3083 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3084 		return core_scsi3_pro_preempt(cmd, type, scope, res_key,
3085 					      sa_res_key, preempt_type);
3086 	default:
3087 		pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3088 			" Type: 0x%02x\n", (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "", type);
3089 		return TCM_INVALID_CDB_FIELD;
3090 	}
3091 }
3092 
3093 
3094 static sense_reason_t
3095 core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
3096 		u64 sa_res_key, int aptpl, int unreg)
3097 {
3098 	struct se_session *se_sess = cmd->se_sess;
3099 	struct se_device *dev = cmd->se_dev;
3100 	struct se_dev_entry *dest_se_deve = NULL;
3101 	struct se_lun *se_lun = cmd->se_lun;
3102 	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3103 	struct se_port *se_port;
3104 	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3105 	const struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3106 	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3107 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3108 	unsigned char *buf;
3109 	unsigned char *initiator_str;
3110 	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
3111 	u32 tid_len, tmp_tid_len;
3112 	int new_reg = 0, type, scope, matching_iname;
3113 	sense_reason_t ret;
3114 	unsigned short rtpi;
3115 	unsigned char proto_ident;
3116 
3117 	if (!se_sess || !se_lun) {
3118 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3119 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3120 	}
3121 
3122 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3123 	se_tpg = se_sess->se_tpg;
3124 	tf_ops = se_tpg->se_tpg_tfo;
3125 	/*
3126 	 * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3127 	 *	Register behaviors for a REGISTER AND MOVE service action
3128 	 *
3129 	 * Locate the existing *pr_reg via struct se_node_acl pointers
3130 	 */
3131 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3132 				se_sess);
3133 	if (!pr_reg) {
3134 		pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3135 			" *pr_reg for REGISTER_AND_MOVE\n");
3136 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3137 	}
3138 	/*
3139 	 * The provided reservation key much match the existing reservation key
3140 	 * provided during this initiator's I_T nexus registration.
3141 	 */
3142 	if (res_key != pr_reg->pr_res_key) {
3143 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3144 			" res_key: 0x%016Lx does not match existing SA REGISTER"
3145 			" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3146 		ret = TCM_RESERVATION_CONFLICT;
3147 		goto out_put_pr_reg;
3148 	}
3149 	/*
3150 	 * The service active reservation key needs to be non zero
3151 	 */
3152 	if (!sa_res_key) {
3153 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3154 			" sa_res_key\n");
3155 		ret = TCM_INVALID_PARAMETER_LIST;
3156 		goto out_put_pr_reg;
3157 	}
3158 
3159 	/*
3160 	 * Determine the Relative Target Port Identifier where the reservation
3161 	 * will be moved to for the TransportID containing SCSI initiator WWN
3162 	 * information.
3163 	 */
3164 	buf = transport_kmap_data_sg(cmd);
3165 	if (!buf) {
3166 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3167 		goto out_put_pr_reg;
3168 	}
3169 
3170 	rtpi = (buf[18] & 0xff) << 8;
3171 	rtpi |= buf[19] & 0xff;
3172 	tid_len = (buf[20] & 0xff) << 24;
3173 	tid_len |= (buf[21] & 0xff) << 16;
3174 	tid_len |= (buf[22] & 0xff) << 8;
3175 	tid_len |= buf[23] & 0xff;
3176 	transport_kunmap_data_sg(cmd);
3177 	buf = NULL;
3178 
3179 	if ((tid_len + 24) != cmd->data_length) {
3180 		pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3181 			" does not equal CDB data_length: %u\n", tid_len,
3182 			cmd->data_length);
3183 		ret = TCM_INVALID_PARAMETER_LIST;
3184 		goto out_put_pr_reg;
3185 	}
3186 
3187 	spin_lock(&dev->se_port_lock);
3188 	list_for_each_entry(se_port, &dev->dev_sep_list, sep_list) {
3189 		if (se_port->sep_rtpi != rtpi)
3190 			continue;
3191 		dest_se_tpg = se_port->sep_tpg;
3192 		if (!dest_se_tpg)
3193 			continue;
3194 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3195 		if (!dest_tf_ops)
3196 			continue;
3197 
3198 		atomic_inc_mb(&dest_se_tpg->tpg_pr_ref_count);
3199 		spin_unlock(&dev->se_port_lock);
3200 
3201 		if (core_scsi3_tpg_depend_item(dest_se_tpg)) {
3202 			pr_err("core_scsi3_tpg_depend_item() failed"
3203 				" for dest_se_tpg\n");
3204 			atomic_dec_mb(&dest_se_tpg->tpg_pr_ref_count);
3205 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3206 			goto out_put_pr_reg;
3207 		}
3208 
3209 		spin_lock(&dev->se_port_lock);
3210 		break;
3211 	}
3212 	spin_unlock(&dev->se_port_lock);
3213 
3214 	if (!dest_se_tpg || !dest_tf_ops) {
3215 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3216 			" fabric ops from Relative Target Port Identifier:"
3217 			" %hu\n", rtpi);
3218 		ret = TCM_INVALID_PARAMETER_LIST;
3219 		goto out_put_pr_reg;
3220 	}
3221 
3222 	buf = transport_kmap_data_sg(cmd);
3223 	if (!buf) {
3224 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3225 		goto out_put_pr_reg;
3226 	}
3227 	proto_ident = (buf[24] & 0x0f);
3228 
3229 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3230 			" 0x%02x\n", proto_ident);
3231 
3232 	if (proto_ident != dest_tf_ops->get_fabric_proto_ident(dest_se_tpg)) {
3233 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3234 			" proto_ident: 0x%02x does not match ident: 0x%02x"
3235 			" from fabric: %s\n", proto_ident,
3236 			dest_tf_ops->get_fabric_proto_ident(dest_se_tpg),
3237 			dest_tf_ops->get_fabric_name());
3238 		ret = TCM_INVALID_PARAMETER_LIST;
3239 		goto out;
3240 	}
3241 	if (dest_tf_ops->tpg_parse_pr_out_transport_id == NULL) {
3242 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Fabric does not"
3243 			" containg a valid tpg_parse_pr_out_transport_id"
3244 			" function pointer\n");
3245 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3246 		goto out;
3247 	}
3248 	initiator_str = dest_tf_ops->tpg_parse_pr_out_transport_id(dest_se_tpg,
3249 			(const char *)&buf[24], &tmp_tid_len, &iport_ptr);
3250 	if (!initiator_str) {
3251 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3252 			" initiator_str from Transport ID\n");
3253 		ret = TCM_INVALID_PARAMETER_LIST;
3254 		goto out;
3255 	}
3256 
3257 	transport_kunmap_data_sg(cmd);
3258 	buf = NULL;
3259 
3260 	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3261 		" %s\n", dest_tf_ops->get_fabric_name(), (iport_ptr != NULL) ?
3262 		"port" : "device", initiator_str, (iport_ptr != NULL) ?
3263 		iport_ptr : "");
3264 	/*
3265 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3266 	 * action specifies a TransportID that is the same as the initiator port
3267 	 * of the I_T nexus for the command received, then the command shall
3268 	 * be terminated with CHECK CONDITION status, with the sense key set to
3269 	 * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3270 	 * IN PARAMETER LIST.
3271 	 */
3272 	pr_reg_nacl = pr_reg->pr_reg_nacl;
3273 	matching_iname = (!strcmp(initiator_str,
3274 				  pr_reg_nacl->initiatorname)) ? 1 : 0;
3275 	if (!matching_iname)
3276 		goto after_iport_check;
3277 
3278 	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3279 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3280 			" matches: %s on received I_T Nexus\n", initiator_str,
3281 			pr_reg_nacl->initiatorname);
3282 		ret = TCM_INVALID_PARAMETER_LIST;
3283 		goto out;
3284 	}
3285 	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3286 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3287 			" matches: %s %s on received I_T Nexus\n",
3288 			initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3289 			pr_reg->pr_reg_isid);
3290 		ret = TCM_INVALID_PARAMETER_LIST;
3291 		goto out;
3292 	}
3293 after_iport_check:
3294 	/*
3295 	 * Locate the destination struct se_node_acl from the received Transport ID
3296 	 */
3297 	spin_lock_irq(&dest_se_tpg->acl_node_lock);
3298 	dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3299 				initiator_str);
3300 	if (dest_node_acl)
3301 		atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
3302 	spin_unlock_irq(&dest_se_tpg->acl_node_lock);
3303 
3304 	if (!dest_node_acl) {
3305 		pr_err("Unable to locate %s dest_node_acl for"
3306 			" TransportID%s\n", dest_tf_ops->get_fabric_name(),
3307 			initiator_str);
3308 		ret = TCM_INVALID_PARAMETER_LIST;
3309 		goto out;
3310 	}
3311 
3312 	if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
3313 		pr_err("core_scsi3_nodeacl_depend_item() for"
3314 			" dest_node_acl\n");
3315 		atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
3316 		dest_node_acl = NULL;
3317 		ret = TCM_INVALID_PARAMETER_LIST;
3318 		goto out;
3319 	}
3320 
3321 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3322 		" %s from TransportID\n", dest_tf_ops->get_fabric_name(),
3323 		dest_node_acl->initiatorname);
3324 
3325 	/*
3326 	 * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3327 	 * PORT IDENTIFIER.
3328 	 */
3329 	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3330 	if (!dest_se_deve) {
3331 		pr_err("Unable to locate %s dest_se_deve from RTPI:"
3332 			" %hu\n",  dest_tf_ops->get_fabric_name(), rtpi);
3333 		ret = TCM_INVALID_PARAMETER_LIST;
3334 		goto out;
3335 	}
3336 
3337 	if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
3338 		pr_err("core_scsi3_lunacl_depend_item() failed\n");
3339 		atomic_dec_mb(&dest_se_deve->pr_ref_count);
3340 		dest_se_deve = NULL;
3341 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3342 		goto out;
3343 	}
3344 
3345 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3346 		" ACL for dest_se_deve->mapped_lun: %u\n",
3347 		dest_tf_ops->get_fabric_name(), dest_node_acl->initiatorname,
3348 		dest_se_deve->mapped_lun);
3349 
3350 	/*
3351 	 * A persistent reservation needs to already existing in order to
3352 	 * successfully complete the REGISTER_AND_MOVE service action..
3353 	 */
3354 	spin_lock(&dev->dev_reservation_lock);
3355 	pr_res_holder = dev->dev_pr_res_holder;
3356 	if (!pr_res_holder) {
3357 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3358 			" currently held\n");
3359 		spin_unlock(&dev->dev_reservation_lock);
3360 		ret = TCM_INVALID_CDB_FIELD;
3361 		goto out;
3362 	}
3363 	/*
3364 	 * The received on I_T Nexus must be the reservation holder.
3365 	 *
3366 	 * From spc4r17 section 5.7.8  Table 50 --
3367 	 * 	Register behaviors for a REGISTER AND MOVE service action
3368 	 */
3369 	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
3370 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3371 			" Nexus is not reservation holder\n");
3372 		spin_unlock(&dev->dev_reservation_lock);
3373 		ret = TCM_RESERVATION_CONFLICT;
3374 		goto out;
3375 	}
3376 	/*
3377 	 * From spc4r17 section 5.7.8: registering and moving reservation
3378 	 *
3379 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3380 	 * action is received and the established persistent reservation is a
3381 	 * Write Exclusive - All Registrants type or Exclusive Access -
3382 	 * All Registrants type reservation, then the command shall be completed
3383 	 * with RESERVATION CONFLICT status.
3384 	 */
3385 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3386 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3387 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3388 			" reservation for type: %s\n",
3389 			core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3390 		spin_unlock(&dev->dev_reservation_lock);
3391 		ret = TCM_RESERVATION_CONFLICT;
3392 		goto out;
3393 	}
3394 	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3395 	/*
3396 	 * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3397 	 */
3398 	type = pr_res_holder->pr_res_type;
3399 	scope = pr_res_holder->pr_res_type;
3400 	/*
3401 	 * c) Associate the reservation key specified in the SERVICE ACTION
3402 	 *    RESERVATION KEY field with the I_T nexus specified as the
3403 	 *    destination of the register and move, where:
3404 	 *    A) The I_T nexus is specified by the TransportID and the
3405 	 *	 RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3406 	 *    B) Regardless of the TransportID format used, the association for
3407 	 *       the initiator port is based on either the initiator port name
3408 	 *       (see 3.1.71) on SCSI transport protocols where port names are
3409 	 *       required or the initiator port identifier (see 3.1.70) on SCSI
3410 	 *       transport protocols where port names are not required;
3411 	 * d) Register the reservation key specified in the SERVICE ACTION
3412 	 *    RESERVATION KEY field;
3413 	 * e) Retain the reservation key specified in the SERVICE ACTION
3414 	 *    RESERVATION KEY field and associated information;
3415 	 *
3416 	 * Also, It is not an error for a REGISTER AND MOVE service action to
3417 	 * register an I_T nexus that is already registered with the same
3418 	 * reservation key or a different reservation key.
3419 	 */
3420 	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3421 					iport_ptr);
3422 	if (!dest_pr_reg) {
3423 		if (core_scsi3_alloc_registration(cmd->se_dev,
3424 				dest_node_acl, dest_se_deve, iport_ptr,
3425 				sa_res_key, 0, aptpl, 2, 1)) {
3426 			spin_unlock(&dev->dev_reservation_lock);
3427 			ret = TCM_INVALID_PARAMETER_LIST;
3428 			goto out;
3429 		}
3430 		dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3431 						iport_ptr);
3432 		new_reg = 1;
3433 	}
3434 	/*
3435 	 * f) Release the persistent reservation for the persistent reservation
3436 	 *    holder (i.e., the I_T nexus on which the
3437 	 */
3438 	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
3439 					  dev->dev_pr_res_holder, 0, 0);
3440 	/*
3441 	 * g) Move the persistent reservation to the specified I_T nexus using
3442 	 *    the same scope and type as the persistent reservation released in
3443 	 *    item f); and
3444 	 */
3445 	dev->dev_pr_res_holder = dest_pr_reg;
3446 	dest_pr_reg->pr_res_holder = 1;
3447 	dest_pr_reg->pr_res_type = type;
3448 	pr_reg->pr_res_scope = scope;
3449 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
3450 	/*
3451 	 * Increment PRGeneration for existing registrations..
3452 	 */
3453 	if (!new_reg)
3454 		dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3455 	spin_unlock(&dev->dev_reservation_lock);
3456 
3457 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3458 		" created new reservation holder TYPE: %s on object RTPI:"
3459 		" %hu  PRGeneration: 0x%08x\n", dest_tf_ops->get_fabric_name(),
3460 		core_scsi3_pr_dump_type(type), rtpi,
3461 		dest_pr_reg->pr_res_generation);
3462 	pr_debug("SPC-3 PR Successfully moved reservation from"
3463 		" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3464 		tf_ops->get_fabric_name(), pr_reg_nacl->initiatorname,
3465 		i_buf, dest_tf_ops->get_fabric_name(),
3466 		dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3467 		iport_ptr : "");
3468 	/*
3469 	 * It is now safe to release configfs group dependencies for destination
3470 	 * of Transport ID Initiator Device/Port Identifier
3471 	 */
3472 	core_scsi3_lunacl_undepend_item(dest_se_deve);
3473 	core_scsi3_nodeacl_undepend_item(dest_node_acl);
3474 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3475 	/*
3476 	 * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3477 	 * nexus on which PERSISTENT RESERVE OUT command was received.
3478 	 */
3479 	if (unreg) {
3480 		spin_lock(&pr_tmpl->registration_lock);
3481 		__core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3482 		spin_unlock(&pr_tmpl->registration_lock);
3483 	} else
3484 		core_scsi3_put_pr_reg(pr_reg);
3485 
3486 	core_scsi3_update_and_write_aptpl(cmd->se_dev, aptpl);
3487 
3488 	transport_kunmap_data_sg(cmd);
3489 
3490 	core_scsi3_put_pr_reg(dest_pr_reg);
3491 	return 0;
3492 out:
3493 	if (buf)
3494 		transport_kunmap_data_sg(cmd);
3495 	if (dest_se_deve)
3496 		core_scsi3_lunacl_undepend_item(dest_se_deve);
3497 	if (dest_node_acl)
3498 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
3499 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3500 
3501 out_put_pr_reg:
3502 	core_scsi3_put_pr_reg(pr_reg);
3503 	return ret;
3504 }
3505 
3506 static unsigned long long core_scsi3_extract_reservation_key(unsigned char *cdb)
3507 {
3508 	unsigned int __v1, __v2;
3509 
3510 	__v1 = (cdb[0] << 24) | (cdb[1] << 16) | (cdb[2] << 8) | cdb[3];
3511 	__v2 = (cdb[4] << 24) | (cdb[5] << 16) | (cdb[6] << 8) | cdb[7];
3512 
3513 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
3514 }
3515 
3516 /*
3517  * See spc4r17 section 6.14 Table 170
3518  */
3519 sense_reason_t
3520 target_scsi3_emulate_pr_out(struct se_cmd *cmd)
3521 {
3522 	struct se_device *dev = cmd->se_dev;
3523 	unsigned char *cdb = &cmd->t_task_cdb[0];
3524 	unsigned char *buf;
3525 	u64 res_key, sa_res_key;
3526 	int sa, scope, type, aptpl;
3527 	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3528 	sense_reason_t ret;
3529 
3530 	/*
3531 	 * Following spc2r20 5.5.1 Reservations overview:
3532 	 *
3533 	 * If a logical unit has been reserved by any RESERVE command and is
3534 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3535 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
3536 	 * initiator or service action and shall terminate with a RESERVATION
3537 	 * CONFLICT status.
3538 	 */
3539 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
3540 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3541 			" SPC-2 reservation is held, returning"
3542 			" RESERVATION_CONFLICT\n");
3543 		return TCM_RESERVATION_CONFLICT;
3544 	}
3545 
3546 	/*
3547 	 * FIXME: A NULL struct se_session pointer means an this is not coming from
3548 	 * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3549 	 */
3550 	if (!cmd->se_sess)
3551 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3552 
3553 	if (cmd->data_length < 24) {
3554 		pr_warn("SPC-PR: Received PR OUT parameter list"
3555 			" length too small: %u\n", cmd->data_length);
3556 		return TCM_INVALID_PARAMETER_LIST;
3557 	}
3558 
3559 	/*
3560 	 * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3561 	 */
3562 	sa = (cdb[1] & 0x1f);
3563 	scope = (cdb[2] & 0xf0);
3564 	type = (cdb[2] & 0x0f);
3565 
3566 	buf = transport_kmap_data_sg(cmd);
3567 	if (!buf)
3568 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3569 
3570 	/*
3571 	 * From PERSISTENT_RESERVE_OUT parameter list (payload)
3572 	 */
3573 	res_key = core_scsi3_extract_reservation_key(&buf[0]);
3574 	sa_res_key = core_scsi3_extract_reservation_key(&buf[8]);
3575 	/*
3576 	 * REGISTER_AND_MOVE uses a different SA parameter list containing
3577 	 * SCSI TransportIDs.
3578 	 */
3579 	if (sa != PRO_REGISTER_AND_MOVE) {
3580 		spec_i_pt = (buf[20] & 0x08);
3581 		all_tg_pt = (buf[20] & 0x04);
3582 		aptpl = (buf[20] & 0x01);
3583 	} else {
3584 		aptpl = (buf[17] & 0x01);
3585 		unreg = (buf[17] & 0x02);
3586 	}
3587 	/*
3588 	 * If the backend device has been configured to force APTPL metadata
3589 	 * write-out, go ahead and propigate aptpl=1 down now.
3590 	 */
3591 	if (dev->dev_attrib.force_pr_aptpl)
3592 		aptpl = 1;
3593 
3594 	transport_kunmap_data_sg(cmd);
3595 	buf = NULL;
3596 
3597 	/*
3598 	 * SPEC_I_PT=1 is only valid for Service action: REGISTER
3599 	 */
3600 	if (spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER))
3601 		return TCM_INVALID_PARAMETER_LIST;
3602 
3603 	/*
3604 	 * From spc4r17 section 6.14:
3605 	 *
3606 	 * If the SPEC_I_PT bit is set to zero, the service action is not
3607 	 * REGISTER AND MOVE, and the parameter list length is not 24, then
3608 	 * the command shall be terminated with CHECK CONDITION status, with
3609 	 * the sense key set to ILLEGAL REQUEST, and the additional sense
3610 	 * code set to PARAMETER LIST LENGTH ERROR.
3611 	 */
3612 	if (!spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER_AND_MOVE) &&
3613 	    (cmd->data_length != 24)) {
3614 		pr_warn("SPC-PR: Received PR OUT illegal parameter"
3615 			" list length: %u\n", cmd->data_length);
3616 		return TCM_INVALID_PARAMETER_LIST;
3617 	}
3618 
3619 	/*
3620 	 * (core_scsi3_emulate_pro_* function parameters
3621 	 * are defined by spc4r17 Table 174:
3622 	 * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3623 	 */
3624 	switch (sa) {
3625 	case PRO_REGISTER:
3626 		ret = core_scsi3_emulate_pro_register(cmd,
3627 			res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER);
3628 		break;
3629 	case PRO_RESERVE:
3630 		ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3631 		break;
3632 	case PRO_RELEASE:
3633 		ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3634 		break;
3635 	case PRO_CLEAR:
3636 		ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3637 		break;
3638 	case PRO_PREEMPT:
3639 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3640 					res_key, sa_res_key, PREEMPT);
3641 		break;
3642 	case PRO_PREEMPT_AND_ABORT:
3643 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3644 					res_key, sa_res_key, PREEMPT_AND_ABORT);
3645 		break;
3646 	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3647 		ret = core_scsi3_emulate_pro_register(cmd,
3648 			0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER_AND_IGNORE_EXISTING_KEY);
3649 		break;
3650 	case PRO_REGISTER_AND_MOVE:
3651 		ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3652 				sa_res_key, aptpl, unreg);
3653 		break;
3654 	default:
3655 		pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3656 			" action: 0x%02x\n", cdb[1] & 0x1f);
3657 		return TCM_INVALID_CDB_FIELD;
3658 	}
3659 
3660 	if (!ret)
3661 		target_complete_cmd(cmd, GOOD);
3662 	return ret;
3663 }
3664 
3665 /*
3666  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3667  *
3668  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3669  */
3670 static sense_reason_t
3671 core_scsi3_pri_read_keys(struct se_cmd *cmd)
3672 {
3673 	struct se_device *dev = cmd->se_dev;
3674 	struct t10_pr_registration *pr_reg;
3675 	unsigned char *buf;
3676 	u32 add_len = 0, off = 8;
3677 
3678 	if (cmd->data_length < 8) {
3679 		pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3680 			" too small\n", cmd->data_length);
3681 		return TCM_INVALID_CDB_FIELD;
3682 	}
3683 
3684 	buf = transport_kmap_data_sg(cmd);
3685 	if (!buf)
3686 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3687 
3688 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3689 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3690 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3691 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3692 
3693 	spin_lock(&dev->t10_pr.registration_lock);
3694 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
3695 			pr_reg_list) {
3696 		/*
3697 		 * Check for overflow of 8byte PRI READ_KEYS payload and
3698 		 * next reservation key list descriptor.
3699 		 */
3700 		if ((add_len + 8) > (cmd->data_length - 8))
3701 			break;
3702 
3703 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3704 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3705 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3706 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3707 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3708 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3709 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3710 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3711 
3712 		add_len += 8;
3713 	}
3714 	spin_unlock(&dev->t10_pr.registration_lock);
3715 
3716 	buf[4] = ((add_len >> 24) & 0xff);
3717 	buf[5] = ((add_len >> 16) & 0xff);
3718 	buf[6] = ((add_len >> 8) & 0xff);
3719 	buf[7] = (add_len & 0xff);
3720 
3721 	transport_kunmap_data_sg(cmd);
3722 
3723 	return 0;
3724 }
3725 
3726 /*
3727  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3728  *
3729  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3730  */
3731 static sense_reason_t
3732 core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3733 {
3734 	struct se_device *dev = cmd->se_dev;
3735 	struct t10_pr_registration *pr_reg;
3736 	unsigned char *buf;
3737 	u64 pr_res_key;
3738 	u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
3739 
3740 	if (cmd->data_length < 8) {
3741 		pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3742 			" too small\n", cmd->data_length);
3743 		return TCM_INVALID_CDB_FIELD;
3744 	}
3745 
3746 	buf = transport_kmap_data_sg(cmd);
3747 	if (!buf)
3748 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3749 
3750 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3751 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3752 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3753 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3754 
3755 	spin_lock(&dev->dev_reservation_lock);
3756 	pr_reg = dev->dev_pr_res_holder;
3757 	if (pr_reg) {
3758 		/*
3759 		 * Set the hardcoded Additional Length
3760 		 */
3761 		buf[4] = ((add_len >> 24) & 0xff);
3762 		buf[5] = ((add_len >> 16) & 0xff);
3763 		buf[6] = ((add_len >> 8) & 0xff);
3764 		buf[7] = (add_len & 0xff);
3765 
3766 		if (cmd->data_length < 22)
3767 			goto err;
3768 
3769 		/*
3770 		 * Set the Reservation key.
3771 		 *
3772 		 * From spc4r17, section 5.7.10:
3773 		 * A persistent reservation holder has its reservation key
3774 		 * returned in the parameter data from a PERSISTENT
3775 		 * RESERVE IN command with READ RESERVATION service action as
3776 		 * follows:
3777 		 * a) For a persistent reservation of the type Write Exclusive
3778 		 *    - All Registrants or Exclusive Access ­ All Regitrants,
3779 		 *      the reservation key shall be set to zero; or
3780 		 * b) For all other persistent reservation types, the
3781 		 *    reservation key shall be set to the registered
3782 		 *    reservation key for the I_T nexus that holds the
3783 		 *    persistent reservation.
3784 		 */
3785 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3786 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3787 			pr_res_key = 0;
3788 		else
3789 			pr_res_key = pr_reg->pr_res_key;
3790 
3791 		buf[8] = ((pr_res_key >> 56) & 0xff);
3792 		buf[9] = ((pr_res_key >> 48) & 0xff);
3793 		buf[10] = ((pr_res_key >> 40) & 0xff);
3794 		buf[11] = ((pr_res_key >> 32) & 0xff);
3795 		buf[12] = ((pr_res_key >> 24) & 0xff);
3796 		buf[13] = ((pr_res_key >> 16) & 0xff);
3797 		buf[14] = ((pr_res_key >> 8) & 0xff);
3798 		buf[15] = (pr_res_key & 0xff);
3799 		/*
3800 		 * Set the SCOPE and TYPE
3801 		 */
3802 		buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3803 			  (pr_reg->pr_res_type & 0x0f);
3804 	}
3805 
3806 err:
3807 	spin_unlock(&dev->dev_reservation_lock);
3808 	transport_kunmap_data_sg(cmd);
3809 
3810 	return 0;
3811 }
3812 
3813 /*
3814  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3815  *
3816  * See spc4r17 section 6.13.4 Table 165
3817  */
3818 static sense_reason_t
3819 core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3820 {
3821 	struct se_device *dev = cmd->se_dev;
3822 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3823 	unsigned char *buf;
3824 	u16 add_len = 8; /* Hardcoded to 8. */
3825 
3826 	if (cmd->data_length < 6) {
3827 		pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
3828 			" %u too small\n", cmd->data_length);
3829 		return TCM_INVALID_CDB_FIELD;
3830 	}
3831 
3832 	buf = transport_kmap_data_sg(cmd);
3833 	if (!buf)
3834 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3835 
3836 	buf[0] = ((add_len >> 8) & 0xff);
3837 	buf[1] = (add_len & 0xff);
3838 	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
3839 	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
3840 	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
3841 	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
3842 	/*
3843 	 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
3844 	 * set the TMV: Task Mask Valid bit.
3845 	 */
3846 	buf[3] |= 0x80;
3847 	/*
3848 	 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
3849 	 */
3850 	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
3851 	/*
3852 	 * PTPL_A: Persistence across Target Power Loss Active bit
3853 	 */
3854 	if (pr_tmpl->pr_aptpl_active)
3855 		buf[3] |= 0x01;
3856 	/*
3857 	 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
3858 	 */
3859 	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3860 	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
3861 	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
3862 	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
3863 	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
3864 	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3865 
3866 	transport_kunmap_data_sg(cmd);
3867 
3868 	return 0;
3869 }
3870 
3871 /*
3872  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
3873  *
3874  * See spc4r17 section 6.13.5 Table 168 and 169
3875  */
3876 static sense_reason_t
3877 core_scsi3_pri_read_full_status(struct se_cmd *cmd)
3878 {
3879 	struct se_device *dev = cmd->se_dev;
3880 	struct se_node_acl *se_nacl;
3881 	struct se_portal_group *se_tpg;
3882 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
3883 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3884 	unsigned char *buf;
3885 	u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
3886 	u32 off = 8; /* off into first Full Status descriptor */
3887 	int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
3888 	bool all_reg = false;
3889 
3890 	if (cmd->data_length < 8) {
3891 		pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
3892 			" too small\n", cmd->data_length);
3893 		return TCM_INVALID_CDB_FIELD;
3894 	}
3895 
3896 	buf = transport_kmap_data_sg(cmd);
3897 	if (!buf)
3898 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3899 
3900 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3901 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3902 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3903 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3904 
3905 	spin_lock(&dev->dev_reservation_lock);
3906 	if (dev->dev_pr_res_holder) {
3907 		struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
3908 
3909 		if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
3910 		    pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
3911 			all_reg = true;
3912 			pr_res_type = pr_holder->pr_res_type;
3913 			pr_res_scope = pr_holder->pr_res_scope;
3914 		}
3915 	}
3916 	spin_unlock(&dev->dev_reservation_lock);
3917 
3918 	spin_lock(&pr_tmpl->registration_lock);
3919 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3920 			&pr_tmpl->registration_list, pr_reg_list) {
3921 
3922 		se_nacl = pr_reg->pr_reg_nacl;
3923 		se_tpg = pr_reg->pr_reg_nacl->se_tpg;
3924 		add_desc_len = 0;
3925 
3926 		atomic_inc_mb(&pr_reg->pr_res_holders);
3927 		spin_unlock(&pr_tmpl->registration_lock);
3928 		/*
3929 		 * Determine expected length of $FABRIC_MOD specific
3930 		 * TransportID full status descriptor..
3931 		 */
3932 		exp_desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id_len(
3933 				se_tpg, se_nacl, pr_reg, &format_code);
3934 
3935 		if ((exp_desc_len + add_len) > cmd->data_length) {
3936 			pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
3937 				" out of buffer: %d\n", cmd->data_length);
3938 			spin_lock(&pr_tmpl->registration_lock);
3939 			atomic_dec_mb(&pr_reg->pr_res_holders);
3940 			break;
3941 		}
3942 		/*
3943 		 * Set RESERVATION KEY
3944 		 */
3945 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3946 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3947 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3948 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3949 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3950 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3951 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3952 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3953 		off += 4; /* Skip Over Reserved area */
3954 
3955 		/*
3956 		 * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
3957 		 */
3958 		if (pr_reg->pr_reg_all_tg_pt)
3959 			buf[off] = 0x02;
3960 		/*
3961 		 * The struct se_lun pointer will be present for the
3962 		 * reservation holder for PR_HOLDER bit.
3963 		 *
3964 		 * Also, if this registration is the reservation
3965 		 * holder or there is an All Registrants reservation
3966 		 * active, fill in SCOPE and TYPE in the next byte.
3967 		 */
3968 		if (pr_reg->pr_res_holder) {
3969 			buf[off++] |= 0x01;
3970 			buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
3971 				     (pr_reg->pr_res_type & 0x0f);
3972 		} else if (all_reg) {
3973 			buf[off++] |= 0x01;
3974 			buf[off++] = (pr_res_scope & 0xf0) |
3975 				     (pr_res_type & 0x0f);
3976 		} else {
3977 			off += 2;
3978 		}
3979 
3980 		off += 4; /* Skip over reserved area */
3981 		/*
3982 		 * From spc4r17 6.3.15:
3983 		 *
3984 		 * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
3985 		 * IDENTIFIER field contains the relative port identifier (see
3986 		 * 3.1.120) of the target port that is part of the I_T nexus
3987 		 * described by this full status descriptor. If the ALL_TG_PT
3988 		 * bit is set to one, the contents of the RELATIVE TARGET PORT
3989 		 * IDENTIFIER field are not defined by this standard.
3990 		 */
3991 		if (!pr_reg->pr_reg_all_tg_pt) {
3992 			struct se_port *port = pr_reg->pr_reg_tg_pt_lun->lun_sep;
3993 
3994 			buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
3995 			buf[off++] = (port->sep_rtpi & 0xff);
3996 		} else
3997 			off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */
3998 
3999 		/*
4000 		 * Now, have the $FABRIC_MOD fill in the protocol identifier
4001 		 */
4002 		desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id(se_tpg,
4003 				se_nacl, pr_reg, &format_code, &buf[off+4]);
4004 
4005 		spin_lock(&pr_tmpl->registration_lock);
4006 		atomic_dec_mb(&pr_reg->pr_res_holders);
4007 		/*
4008 		 * Set the ADDITIONAL DESCRIPTOR LENGTH
4009 		 */
4010 		buf[off++] = ((desc_len >> 24) & 0xff);
4011 		buf[off++] = ((desc_len >> 16) & 0xff);
4012 		buf[off++] = ((desc_len >> 8) & 0xff);
4013 		buf[off++] = (desc_len & 0xff);
4014 		/*
4015 		 * Size of full desctipor header minus TransportID
4016 		 * containing $FABRIC_MOD specific) initiator device/port
4017 		 * WWN information.
4018 		 *
4019 		 *  See spc4r17 Section 6.13.5 Table 169
4020 		 */
4021 		add_desc_len = (24 + desc_len);
4022 
4023 		off += desc_len;
4024 		add_len += add_desc_len;
4025 	}
4026 	spin_unlock(&pr_tmpl->registration_lock);
4027 	/*
4028 	 * Set ADDITIONAL_LENGTH
4029 	 */
4030 	buf[4] = ((add_len >> 24) & 0xff);
4031 	buf[5] = ((add_len >> 16) & 0xff);
4032 	buf[6] = ((add_len >> 8) & 0xff);
4033 	buf[7] = (add_len & 0xff);
4034 
4035 	transport_kunmap_data_sg(cmd);
4036 
4037 	return 0;
4038 }
4039 
4040 sense_reason_t
4041 target_scsi3_emulate_pr_in(struct se_cmd *cmd)
4042 {
4043 	sense_reason_t ret;
4044 
4045 	/*
4046 	 * Following spc2r20 5.5.1 Reservations overview:
4047 	 *
4048 	 * If a logical unit has been reserved by any RESERVE command and is
4049 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4050 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
4051 	 * initiator or service action and shall terminate with a RESERVATION
4052 	 * CONFLICT status.
4053 	 */
4054 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
4055 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4056 			" SPC-2 reservation is held, returning"
4057 			" RESERVATION_CONFLICT\n");
4058 		return TCM_RESERVATION_CONFLICT;
4059 	}
4060 
4061 	switch (cmd->t_task_cdb[1] & 0x1f) {
4062 	case PRI_READ_KEYS:
4063 		ret = core_scsi3_pri_read_keys(cmd);
4064 		break;
4065 	case PRI_READ_RESERVATION:
4066 		ret = core_scsi3_pri_read_reservation(cmd);
4067 		break;
4068 	case PRI_REPORT_CAPABILITIES:
4069 		ret = core_scsi3_pri_report_capabilities(cmd);
4070 		break;
4071 	case PRI_READ_FULL_STATUS:
4072 		ret = core_scsi3_pri_read_full_status(cmd);
4073 		break;
4074 	default:
4075 		pr_err("Unknown PERSISTENT_RESERVE_IN service"
4076 			" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4077 		return TCM_INVALID_CDB_FIELD;
4078 	}
4079 
4080 	if (!ret)
4081 		target_complete_cmd(cmd, GOOD);
4082 	return ret;
4083 }
4084 
4085 sense_reason_t
4086 target_check_reservation(struct se_cmd *cmd)
4087 {
4088 	struct se_device *dev = cmd->se_dev;
4089 	sense_reason_t ret;
4090 
4091 	if (!cmd->se_sess)
4092 		return 0;
4093 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
4094 		return 0;
4095 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
4096 		return 0;
4097 
4098 	spin_lock(&dev->dev_reservation_lock);
4099 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
4100 		ret = target_scsi2_reservation_check(cmd);
4101 	else
4102 		ret = target_scsi3_pr_reservation_check(cmd);
4103 	spin_unlock(&dev->dev_reservation_lock);
4104 
4105 	return ret;
4106 }
4107