xref: /openbmc/linux/drivers/target/target_core_pr.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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/vmalloc.h>
31 #include <linux/file.h>
32 #include <scsi/scsi_proto.h>
33 #include <asm/unaligned.h>
34 
35 #include <target/target_core_base.h>
36 #include <target/target_core_backend.h>
37 #include <target/target_core_fabric.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 	struct t10_pr_registration *dest_pr_reg;
48 	struct se_portal_group *dest_tpg;
49 	struct se_node_acl *dest_node_acl;
50 	struct se_dev_entry *dest_se_deve;
51 	struct list_head dest_list;
52 };
53 
54 void core_pr_dump_initiator_port(
55 	struct t10_pr_registration *pr_reg,
56 	char *buf,
57 	u32 size)
58 {
59 	if (!pr_reg->isid_present_at_reg)
60 		buf[0] = '\0';
61 
62 	snprintf(buf, size, ",i,0x%s", pr_reg->pr_reg_isid);
63 }
64 
65 enum register_type {
66 	REGISTER,
67 	REGISTER_AND_IGNORE_EXISTING_KEY,
68 	REGISTER_AND_MOVE,
69 };
70 
71 enum preempt_type {
72 	PREEMPT,
73 	PREEMPT_AND_ABORT,
74 };
75 
76 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
77 					      struct t10_pr_registration *, int, int);
78 
79 static int is_reservation_holder(
80 	struct t10_pr_registration *pr_res_holder,
81 	struct t10_pr_registration *pr_reg)
82 {
83 	int pr_res_type;
84 
85 	if (pr_res_holder) {
86 		pr_res_type = pr_res_holder->pr_res_type;
87 
88 		return pr_res_holder == pr_reg ||
89 		       pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
90 		       pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG;
91 	}
92 	return 0;
93 }
94 
95 static sense_reason_t
96 target_scsi2_reservation_check(struct se_cmd *cmd)
97 {
98 	struct se_device *dev = cmd->se_dev;
99 	struct se_session *sess = cmd->se_sess;
100 
101 	switch (cmd->t_task_cdb[0]) {
102 	case INQUIRY:
103 	case RELEASE:
104 	case RELEASE_10:
105 		return 0;
106 	default:
107 		break;
108 	}
109 
110 	if (!dev->dev_reserved_node_acl || !sess)
111 		return 0;
112 
113 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
114 		return TCM_RESERVATION_CONFLICT;
115 
116 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
117 		if (dev->dev_res_bin_isid != sess->sess_bin_isid)
118 			return TCM_RESERVATION_CONFLICT;
119 	}
120 
121 	return 0;
122 }
123 
124 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
125 					struct se_node_acl *, struct se_session *);
126 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
127 
128 static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
129 {
130 	struct se_session *se_sess = cmd->se_sess;
131 	struct se_device *dev = cmd->se_dev;
132 	struct t10_pr_registration *pr_reg;
133 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
134 	int conflict = 0;
135 
136 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
137 			se_sess);
138 	if (pr_reg) {
139 		/*
140 		 * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
141 		 * behavior
142 		 *
143 		 * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
144 		 * status, but no reservation shall be established and the
145 		 * persistent reservation shall not be changed, if the command
146 		 * is received from a) and b) below.
147 		 *
148 		 * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
149 		 * status, but the persistent reservation shall not be released,
150 		 * if the command is received from a) and b)
151 		 *
152 		 * a) An I_T nexus that is a persistent reservation holder; or
153 		 * b) An I_T nexus that is registered if a registrants only or
154 		 *    all registrants type persistent reservation is present.
155 		 *
156 		 * In all other cases, a RESERVE(6) command, RESERVE(10) command,
157 		 * RELEASE(6) command, or RELEASE(10) command shall be processed
158 		 * as defined in SPC-2.
159 		 */
160 		if (pr_reg->pr_res_holder) {
161 			core_scsi3_put_pr_reg(pr_reg);
162 			return 1;
163 		}
164 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
165 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
166 		    (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
167 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
168 			core_scsi3_put_pr_reg(pr_reg);
169 			return 1;
170 		}
171 		core_scsi3_put_pr_reg(pr_reg);
172 		conflict = 1;
173 	} else {
174 		/*
175 		 * Following spc2r20 5.5.1 Reservations overview:
176 		 *
177 		 * If a logical unit has executed a PERSISTENT RESERVE OUT
178 		 * command with the REGISTER or the REGISTER AND IGNORE
179 		 * EXISTING KEY service action and is still registered by any
180 		 * initiator, all RESERVE commands and all RELEASE commands
181 		 * regardless of initiator shall conflict and shall terminate
182 		 * with a RESERVATION CONFLICT status.
183 		 */
184 		spin_lock(&pr_tmpl->registration_lock);
185 		conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
186 		spin_unlock(&pr_tmpl->registration_lock);
187 	}
188 
189 	if (conflict) {
190 		pr_err("Received legacy SPC-2 RESERVE/RELEASE"
191 			" while active SPC-3 registrations exist,"
192 			" returning RESERVATION_CONFLICT\n");
193 		return -EBUSY;
194 	}
195 
196 	return 0;
197 }
198 
199 sense_reason_t
200 target_scsi2_reservation_release(struct se_cmd *cmd)
201 {
202 	struct se_device *dev = cmd->se_dev;
203 	struct se_session *sess = cmd->se_sess;
204 	struct se_portal_group *tpg;
205 	int rc;
206 
207 	if (!sess || !sess->se_tpg)
208 		goto out;
209 	rc = target_check_scsi2_reservation_conflict(cmd);
210 	if (rc == 1)
211 		goto out;
212 	if (rc < 0)
213 		return TCM_RESERVATION_CONFLICT;
214 
215 	spin_lock(&dev->dev_reservation_lock);
216 	if (!dev->dev_reserved_node_acl || !sess)
217 		goto out_unlock;
218 
219 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
220 		goto out_unlock;
221 
222 	if (dev->dev_res_bin_isid != sess->sess_bin_isid)
223 		goto out_unlock;
224 
225 	dev->dev_reserved_node_acl = NULL;
226 	dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
227 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
228 		dev->dev_res_bin_isid = 0;
229 		dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS_WITH_ISID;
230 	}
231 	tpg = sess->se_tpg;
232 	pr_debug("SCSI-2 Released reservation for %s LUN: %llu ->"
233 		" MAPPED LUN: %llu for %s\n",
234 		tpg->se_tpg_tfo->get_fabric_name(),
235 		cmd->se_lun->unpacked_lun, cmd->orig_fe_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: %llu %s\n",
280 			cmd->se_lun->unpacked_lun,
281 			dev->dev_reserved_node_acl->initiatorname);
282 		pr_err("Current attempt - LUN: %llu -> MAPPED LUN: %llu"
283 			" from %s \n", cmd->se_lun->unpacked_lun,
284 			cmd->orig_fe_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: %llu -> MAPPED LUN: %llu"
297 		" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
298 		cmd->se_lun->unpacked_lun, cmd->orig_fe_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(struct se_cmd *cmd, u32 pr_reg_type,
317 					bool isid_mismatch)
318 {
319 	unsigned char *cdb = cmd->t_task_cdb;
320 	struct se_session *se_sess = cmd->se_sess;
321 	struct se_node_acl *nacl = se_sess->se_node_acl;
322 	int other_cdb = 0;
323 	int registered_nexus = 0, ret = 1; /* Conflict by default */
324 	int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
325 	int we = 0; /* Write Exclusive */
326 	int legacy = 0; /* Act like a legacy device and return
327 			 * RESERVATION CONFLICT on some CDBs */
328 
329 	if (isid_mismatch) {
330 		registered_nexus = 0;
331 	} else {
332 		struct se_dev_entry *se_deve;
333 
334 		rcu_read_lock();
335 		se_deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
336 		if (se_deve)
337 			registered_nexus = test_bit(DEF_PR_REG_ACTIVE,
338 						    &se_deve->deve_flags);
339 		rcu_read_unlock();
340 	}
341 
342 	switch (pr_reg_type) {
343 	case PR_TYPE_WRITE_EXCLUSIVE:
344 		we = 1;
345 	case PR_TYPE_EXCLUSIVE_ACCESS:
346 		/*
347 		 * Some commands are only allowed for the persistent reservation
348 		 * holder.
349 		 */
350 		break;
351 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
352 		we = 1;
353 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
354 		/*
355 		 * Some commands are only allowed for registered I_T Nexuses.
356 		 */
357 		reg_only = 1;
358 		break;
359 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
360 		we = 1;
361 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
362 		/*
363 		 * Each registered I_T Nexus is a reservation holder.
364 		 */
365 		all_reg = 1;
366 		break;
367 	default:
368 		return -EINVAL;
369 	}
370 	/*
371 	 * Referenced from spc4r17 table 45 for *NON* PR holder access
372 	 */
373 	switch (cdb[0]) {
374 	case SECURITY_PROTOCOL_IN:
375 		if (registered_nexus)
376 			return 0;
377 		ret = (we) ? 0 : 1;
378 		break;
379 	case MODE_SENSE:
380 	case MODE_SENSE_10:
381 	case READ_ATTRIBUTE:
382 	case READ_BUFFER:
383 	case RECEIVE_DIAGNOSTIC:
384 		if (legacy) {
385 			ret = 1;
386 			break;
387 		}
388 		if (registered_nexus) {
389 			ret = 0;
390 			break;
391 		}
392 		ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
393 		break;
394 	case PERSISTENT_RESERVE_OUT:
395 		/*
396 		 * This follows PERSISTENT_RESERVE_OUT service actions that
397 		 * are allowed in the presence of various reservations.
398 		 * See spc4r17, table 46
399 		 */
400 		switch (cdb[1] & 0x1f) {
401 		case PRO_CLEAR:
402 		case PRO_PREEMPT:
403 		case PRO_PREEMPT_AND_ABORT:
404 			ret = (registered_nexus) ? 0 : 1;
405 			break;
406 		case PRO_REGISTER:
407 		case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
408 			ret = 0;
409 			break;
410 		case PRO_REGISTER_AND_MOVE:
411 		case PRO_RESERVE:
412 			ret = 1;
413 			break;
414 		case PRO_RELEASE:
415 			ret = (registered_nexus) ? 0 : 1;
416 			break;
417 		default:
418 			pr_err("Unknown PERSISTENT_RESERVE_OUT service"
419 				" action: 0x%02x\n", cdb[1] & 0x1f);
420 			return -EINVAL;
421 		}
422 		break;
423 	case RELEASE:
424 	case RELEASE_10:
425 		/* Handled by CRH=1 in target_scsi2_reservation_release() */
426 		ret = 0;
427 		break;
428 	case RESERVE:
429 	case RESERVE_10:
430 		/* Handled by CRH=1 in target_scsi2_reservation_reserve() */
431 		ret = 0;
432 		break;
433 	case TEST_UNIT_READY:
434 		ret = (legacy) ? 1 : 0; /* Conflict for legacy */
435 		break;
436 	case MAINTENANCE_IN:
437 		switch (cdb[1] & 0x1f) {
438 		case MI_MANAGEMENT_PROTOCOL_IN:
439 			if (registered_nexus) {
440 				ret = 0;
441 				break;
442 			}
443 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
444 			break;
445 		case MI_REPORT_SUPPORTED_OPERATION_CODES:
446 		case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
447 			if (legacy) {
448 				ret = 1;
449 				break;
450 			}
451 			if (registered_nexus) {
452 				ret = 0;
453 				break;
454 			}
455 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
456 			break;
457 		case MI_REPORT_ALIASES:
458 		case MI_REPORT_IDENTIFYING_INFORMATION:
459 		case MI_REPORT_PRIORITY:
460 		case MI_REPORT_TARGET_PGS:
461 		case MI_REPORT_TIMESTAMP:
462 			ret = 0; /* Allowed */
463 			break;
464 		default:
465 			pr_err("Unknown MI Service Action: 0x%02x\n",
466 				(cdb[1] & 0x1f));
467 			return -EINVAL;
468 		}
469 		break;
470 	case ACCESS_CONTROL_IN:
471 	case ACCESS_CONTROL_OUT:
472 	case INQUIRY:
473 	case LOG_SENSE:
474 	case SERVICE_ACTION_IN_12:
475 	case REPORT_LUNS:
476 	case REQUEST_SENSE:
477 	case PERSISTENT_RESERVE_IN:
478 		ret = 0; /*/ Allowed CDBs */
479 		break;
480 	default:
481 		other_cdb = 1;
482 		break;
483 	}
484 	/*
485 	 * Case where the CDB is explicitly allowed in the above switch
486 	 * statement.
487 	 */
488 	if (!ret && !other_cdb) {
489 		pr_debug("Allowing explicit CDB: 0x%02x for %s"
490 			" reservation holder\n", cdb[0],
491 			core_scsi3_pr_dump_type(pr_reg_type));
492 
493 		return ret;
494 	}
495 	/*
496 	 * Check if write exclusive initiator ports *NOT* holding the
497 	 * WRITE_EXCLUSIVE_* reservation.
498 	 */
499 	if (we && !registered_nexus) {
500 		if (cmd->data_direction == DMA_TO_DEVICE) {
501 			/*
502 			 * Conflict for write exclusive
503 			 */
504 			pr_debug("%s Conflict for unregistered nexus"
505 				" %s CDB: 0x%02x to %s reservation\n",
506 				transport_dump_cmd_direction(cmd),
507 				se_sess->se_node_acl->initiatorname, cdb[0],
508 				core_scsi3_pr_dump_type(pr_reg_type));
509 			return 1;
510 		} else {
511 			/*
512 			 * Allow non WRITE CDBs for all Write Exclusive
513 			 * PR TYPEs to pass for registered and
514 			 * non-registered_nexuxes NOT holding the reservation.
515 			 *
516 			 * We only make noise for the unregisterd nexuses,
517 			 * as we expect registered non-reservation holding
518 			 * nexuses to issue CDBs.
519 			 */
520 
521 			if (!registered_nexus) {
522 				pr_debug("Allowing implicit CDB: 0x%02x"
523 					" for %s reservation on unregistered"
524 					" nexus\n", cdb[0],
525 					core_scsi3_pr_dump_type(pr_reg_type));
526 			}
527 
528 			return 0;
529 		}
530 	} else if ((reg_only) || (all_reg)) {
531 		if (registered_nexus) {
532 			/*
533 			 * For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
534 			 * allow commands from registered nexuses.
535 			 */
536 
537 			pr_debug("Allowing implicit CDB: 0x%02x for %s"
538 				" reservation\n", cdb[0],
539 				core_scsi3_pr_dump_type(pr_reg_type));
540 
541 			return 0;
542 		}
543        } else if (we && registered_nexus) {
544                /*
545                 * Reads are allowed for Write Exclusive locks
546                 * from all registrants.
547                 */
548                if (cmd->data_direction == DMA_FROM_DEVICE) {
549                        pr_debug("Allowing READ CDB: 0x%02x for %s"
550                                " reservation\n", cdb[0],
551                                core_scsi3_pr_dump_type(pr_reg_type));
552 
553                        return 0;
554                }
555 	}
556 	pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
557 		" for %s reservation\n", transport_dump_cmd_direction(cmd),
558 		(registered_nexus) ? "" : "un",
559 		se_sess->se_node_acl->initiatorname, cdb[0],
560 		core_scsi3_pr_dump_type(pr_reg_type));
561 
562 	return 1; /* Conflict by default */
563 }
564 
565 static sense_reason_t
566 target_scsi3_pr_reservation_check(struct se_cmd *cmd)
567 {
568 	struct se_device *dev = cmd->se_dev;
569 	struct se_session *sess = cmd->se_sess;
570 	u32 pr_reg_type;
571 	bool isid_mismatch = false;
572 
573 	if (!dev->dev_pr_res_holder)
574 		return 0;
575 
576 	pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
577 	cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
578 	if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
579 		goto check_nonholder;
580 
581 	if (dev->dev_pr_res_holder->isid_present_at_reg) {
582 		if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
583 		    sess->sess_bin_isid) {
584 			isid_mismatch = true;
585 			goto check_nonholder;
586 		}
587 	}
588 
589 	return 0;
590 
591 check_nonholder:
592 	if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type, isid_mismatch))
593 		return TCM_RESERVATION_CONFLICT;
594 	return 0;
595 }
596 
597 static u32 core_scsi3_pr_generation(struct se_device *dev)
598 {
599 	u32 prg;
600 
601 	/*
602 	 * PRGeneration field shall contain the value of a 32-bit wrapping
603 	 * counter mainted by the device server.
604 	 *
605 	 * Note that this is done regardless of Active Persist across
606 	 * Target PowerLoss (APTPL)
607 	 *
608 	 * See spc4r17 section 6.3.12 READ_KEYS service action
609 	 */
610 	spin_lock(&dev->dev_reservation_lock);
611 	prg = dev->t10_pr.pr_generation++;
612 	spin_unlock(&dev->dev_reservation_lock);
613 
614 	return prg;
615 }
616 
617 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
618 	struct se_device *dev,
619 	struct se_node_acl *nacl,
620 	struct se_lun *lun,
621 	struct se_dev_entry *dest_deve,
622 	u64 mapped_lun,
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 	/*
644 	 * For destination registrations for ALL_TG_PT=1 and SPEC_I_PT=1,
645 	 * the se_dev_entry->pr_ref will have been already obtained by
646 	 * core_get_se_deve_from_rtpi() or __core_scsi3_alloc_registration().
647 	 *
648 	 * Otherwise, locate se_dev_entry now and obtain a reference until
649 	 * registration completes in __core_scsi3_add_registration().
650 	 */
651 	if (dest_deve) {
652 		pr_reg->pr_reg_deve = dest_deve;
653 	} else {
654 		rcu_read_lock();
655 		pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
656 		if (!pr_reg->pr_reg_deve) {
657 			rcu_read_unlock();
658 			pr_err("Unable to locate PR deve %s mapped_lun: %llu\n",
659 				nacl->initiatorname, mapped_lun);
660 			kmem_cache_free(t10_pr_reg_cache, pr_reg);
661 			return NULL;
662 		}
663 		kref_get(&pr_reg->pr_reg_deve->pr_kref);
664 		rcu_read_unlock();
665 	}
666 	pr_reg->pr_res_mapped_lun = mapped_lun;
667 	pr_reg->pr_aptpl_target_lun = lun->unpacked_lun;
668 	pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
669 	pr_reg->pr_res_key = sa_res_key;
670 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
671 	pr_reg->pr_reg_aptpl = aptpl;
672 	/*
673 	 * If an ISID value for this SCSI Initiator Port exists,
674 	 * save it to the registration now.
675 	 */
676 	if (isid != NULL) {
677 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
678 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
679 		pr_reg->isid_present_at_reg = 1;
680 	}
681 
682 	return pr_reg;
683 }
684 
685 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
686 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
687 
688 /*
689  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
690  * modes.
691  */
692 static struct t10_pr_registration *__core_scsi3_alloc_registration(
693 	struct se_device *dev,
694 	struct se_node_acl *nacl,
695 	struct se_lun *lun,
696 	struct se_dev_entry *deve,
697 	u64 mapped_lun,
698 	unsigned char *isid,
699 	u64 sa_res_key,
700 	int all_tg_pt,
701 	int aptpl)
702 {
703 	struct se_dev_entry *deve_tmp;
704 	struct se_node_acl *nacl_tmp;
705 	struct se_lun_acl *lacl_tmp;
706 	struct se_lun *lun_tmp, *next, *dest_lun;
707 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
708 	struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
709 	int ret;
710 	/*
711 	 * Create a registration for the I_T Nexus upon which the
712 	 * PROUT REGISTER was received.
713 	 */
714 	pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, lun, deve, mapped_lun,
715 						    isid, sa_res_key, all_tg_pt,
716 						    aptpl);
717 	if (!pr_reg)
718 		return NULL;
719 	/*
720 	 * Return pointer to pr_reg for ALL_TG_PT=0
721 	 */
722 	if (!all_tg_pt)
723 		return pr_reg;
724 	/*
725 	 * Create list of matching SCSI Initiator Port registrations
726 	 * for ALL_TG_PT=1
727 	 */
728 	spin_lock(&dev->se_port_lock);
729 	list_for_each_entry_safe(lun_tmp, next, &dev->dev_sep_list, lun_dev_link) {
730 		if (!percpu_ref_tryget_live(&lun_tmp->lun_ref))
731 			continue;
732 		spin_unlock(&dev->se_port_lock);
733 
734 		spin_lock(&lun_tmp->lun_deve_lock);
735 		list_for_each_entry(deve_tmp, &lun_tmp->lun_deve_list, lun_link) {
736 			/*
737 			 * This pointer will be NULL for demo mode MappedLUNs
738 			 * that have not been make explicit via a ConfigFS
739 			 * MappedLUN group for the SCSI Initiator Node ACL.
740 			 */
741 			if (!deve_tmp->se_lun_acl)
742 				continue;
743 
744 			lacl_tmp = rcu_dereference_check(deve_tmp->se_lun_acl,
745 						lockdep_is_held(&lun_tmp->lun_deve_lock));
746 			nacl_tmp = lacl_tmp->se_lun_nacl;
747 			/*
748 			 * Skip the matching struct se_node_acl that is allocated
749 			 * above..
750 			 */
751 			if (nacl == nacl_tmp)
752 				continue;
753 			/*
754 			 * Only perform PR registrations for target ports on
755 			 * the same fabric module as the REGISTER w/ ALL_TG_PT=1
756 			 * arrived.
757 			 */
758 			if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
759 				continue;
760 			/*
761 			 * Look for a matching Initiator Node ACL in ASCII format
762 			 */
763 			if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
764 				continue;
765 
766 			kref_get(&deve_tmp->pr_kref);
767 			spin_unlock(&lun_tmp->lun_deve_lock);
768 			/*
769 			 * Grab a configfs group dependency that is released
770 			 * for the exception path at label out: below, or upon
771 			 * completion of adding ALL_TG_PT=1 registrations in
772 			 * __core_scsi3_add_registration()
773 			 */
774 			ret = core_scsi3_lunacl_depend_item(deve_tmp);
775 			if (ret < 0) {
776 				pr_err("core_scsi3_lunacl_depend"
777 						"_item() failed\n");
778 				percpu_ref_put(&lun_tmp->lun_ref);
779 				kref_put(&deve_tmp->pr_kref, target_pr_kref_release);
780 				goto out;
781 			}
782 			/*
783 			 * Located a matching SCSI Initiator Port on a different
784 			 * port, allocate the pr_reg_atp and attach it to the
785 			 * pr_reg->pr_reg_atp_list that will be processed once
786 			 * the original *pr_reg is processed in
787 			 * __core_scsi3_add_registration()
788 			 */
789 			dest_lun = rcu_dereference_check(deve_tmp->se_lun,
790 				atomic_read(&deve_tmp->pr_kref.refcount) != 0);
791 
792 			pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
793 						nacl_tmp, dest_lun, deve_tmp,
794 						deve_tmp->mapped_lun, NULL,
795 						sa_res_key, all_tg_pt, aptpl);
796 			if (!pr_reg_atp) {
797 				percpu_ref_put(&lun_tmp->lun_ref);
798 				core_scsi3_lunacl_undepend_item(deve_tmp);
799 				goto out;
800 			}
801 
802 			list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
803 				      &pr_reg->pr_reg_atp_list);
804 			spin_lock(&lun_tmp->lun_deve_lock);
805 		}
806 		spin_unlock(&lun_tmp->lun_deve_lock);
807 
808 		spin_lock(&dev->se_port_lock);
809 		percpu_ref_put(&lun_tmp->lun_ref);
810 	}
811 	spin_unlock(&dev->se_port_lock);
812 
813 	return pr_reg;
814 out:
815 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
816 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
817 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
818 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
819 		kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
820 	}
821 	kmem_cache_free(t10_pr_reg_cache, pr_reg);
822 	return NULL;
823 }
824 
825 int core_scsi3_alloc_aptpl_registration(
826 	struct t10_reservation *pr_tmpl,
827 	u64 sa_res_key,
828 	unsigned char *i_port,
829 	unsigned char *isid,
830 	u64 mapped_lun,
831 	unsigned char *t_port,
832 	u16 tpgt,
833 	u64 target_lun,
834 	int res_holder,
835 	int all_tg_pt,
836 	u8 type)
837 {
838 	struct t10_pr_registration *pr_reg;
839 
840 	if (!i_port || !t_port || !sa_res_key) {
841 		pr_err("Illegal parameters for APTPL registration\n");
842 		return -EINVAL;
843 	}
844 
845 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
846 	if (!pr_reg) {
847 		pr_err("Unable to allocate struct t10_pr_registration\n");
848 		return -ENOMEM;
849 	}
850 
851 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
852 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
853 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
854 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
855 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
856 	atomic_set(&pr_reg->pr_res_holders, 0);
857 	pr_reg->pr_reg_nacl = NULL;
858 	pr_reg->pr_reg_deve = NULL;
859 	pr_reg->pr_res_mapped_lun = mapped_lun;
860 	pr_reg->pr_aptpl_target_lun = target_lun;
861 	pr_reg->pr_res_key = sa_res_key;
862 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
863 	pr_reg->pr_reg_aptpl = 1;
864 	pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
865 	pr_reg->pr_res_type = type;
866 	/*
867 	 * If an ISID value had been saved in APTPL metadata for this
868 	 * SCSI Initiator Port, restore it now.
869 	 */
870 	if (isid != NULL) {
871 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
872 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
873 		pr_reg->isid_present_at_reg = 1;
874 	}
875 	/*
876 	 * Copy the i_port and t_port information from caller.
877 	 */
878 	snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
879 	snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
880 	pr_reg->pr_reg_tpgt = tpgt;
881 	/*
882 	 * Set pr_res_holder from caller, the pr_reg who is the reservation
883 	 * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
884 	 * the Initiator Node LUN ACL from the fabric module is created for
885 	 * this registration.
886 	 */
887 	pr_reg->pr_res_holder = res_holder;
888 
889 	list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
890 	pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
891 			" metadata\n", (res_holder) ? "+reservation" : "");
892 	return 0;
893 }
894 
895 static void core_scsi3_aptpl_reserve(
896 	struct se_device *dev,
897 	struct se_portal_group *tpg,
898 	struct se_node_acl *node_acl,
899 	struct t10_pr_registration *pr_reg)
900 {
901 	char i_buf[PR_REG_ISID_ID_LEN];
902 
903 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
904 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
905 
906 	spin_lock(&dev->dev_reservation_lock);
907 	dev->dev_pr_res_holder = pr_reg;
908 	spin_unlock(&dev->dev_reservation_lock);
909 
910 	pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
911 		" new reservation holder TYPE: %s ALL_TG_PT: %d\n",
912 		tpg->se_tpg_tfo->get_fabric_name(),
913 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
914 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
915 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
916 		tpg->se_tpg_tfo->get_fabric_name(), node_acl->initiatorname,
917 		i_buf);
918 }
919 
920 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
921 				struct t10_pr_registration *, enum register_type, int);
922 
923 static int __core_scsi3_check_aptpl_registration(
924 	struct se_device *dev,
925 	struct se_portal_group *tpg,
926 	struct se_lun *lun,
927 	u64 target_lun,
928 	struct se_node_acl *nacl,
929 	u64 mapped_lun)
930 {
931 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
932 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
933 	unsigned char i_port[PR_APTPL_MAX_IPORT_LEN];
934 	unsigned char t_port[PR_APTPL_MAX_TPORT_LEN];
935 	u16 tpgt;
936 
937 	memset(i_port, 0, PR_APTPL_MAX_IPORT_LEN);
938 	memset(t_port, 0, PR_APTPL_MAX_TPORT_LEN);
939 	/*
940 	 * Copy Initiator Port information from struct se_node_acl
941 	 */
942 	snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
943 	snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
944 			tpg->se_tpg_tfo->tpg_get_wwn(tpg));
945 	tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
946 	/*
947 	 * Look for the matching registrations+reservation from those
948 	 * created from APTPL metadata.  Note that multiple registrations
949 	 * may exist for fabrics that use ISIDs in their SCSI Initiator Port
950 	 * TransportIDs.
951 	 */
952 	spin_lock(&pr_tmpl->aptpl_reg_lock);
953 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
954 				pr_reg_aptpl_list) {
955 
956 		if (!strcmp(pr_reg->pr_iport, i_port) &&
957 		     (pr_reg->pr_res_mapped_lun == mapped_lun) &&
958 		    !(strcmp(pr_reg->pr_tport, t_port)) &&
959 		     (pr_reg->pr_reg_tpgt == tpgt) &&
960 		     (pr_reg->pr_aptpl_target_lun == target_lun)) {
961 			/*
962 			 * Obtain the ->pr_reg_deve pointer + reference, that
963 			 * is released by __core_scsi3_add_registration() below.
964 			 */
965 			rcu_read_lock();
966 			pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
967 			if (!pr_reg->pr_reg_deve) {
968 				pr_err("Unable to locate PR APTPL %s mapped_lun:"
969 					" %llu\n", nacl->initiatorname, mapped_lun);
970 				rcu_read_unlock();
971 				continue;
972 			}
973 			kref_get(&pr_reg->pr_reg_deve->pr_kref);
974 			rcu_read_unlock();
975 
976 			pr_reg->pr_reg_nacl = nacl;
977 			pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
978 			list_del(&pr_reg->pr_reg_aptpl_list);
979 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
980 			/*
981 			 * At this point all of the pointers in *pr_reg will
982 			 * be setup, so go ahead and add the registration.
983 			 */
984 			__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
985 			/*
986 			 * If this registration is the reservation holder,
987 			 * make that happen now..
988 			 */
989 			if (pr_reg->pr_res_holder)
990 				core_scsi3_aptpl_reserve(dev, tpg,
991 						nacl, pr_reg);
992 			/*
993 			 * Reenable pr_aptpl_active to accept new metadata
994 			 * updates once the SCSI device is active again..
995 			 */
996 			spin_lock(&pr_tmpl->aptpl_reg_lock);
997 			pr_tmpl->pr_aptpl_active = 1;
998 		}
999 	}
1000 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
1001 
1002 	return 0;
1003 }
1004 
1005 int core_scsi3_check_aptpl_registration(
1006 	struct se_device *dev,
1007 	struct se_portal_group *tpg,
1008 	struct se_lun *lun,
1009 	struct se_node_acl *nacl,
1010 	u64 mapped_lun)
1011 {
1012 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
1013 		return 0;
1014 
1015 	return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
1016 						     lun->unpacked_lun, nacl,
1017 						     mapped_lun);
1018 }
1019 
1020 static void __core_scsi3_dump_registration(
1021 	const struct target_core_fabric_ops *tfo,
1022 	struct se_device *dev,
1023 	struct se_node_acl *nacl,
1024 	struct t10_pr_registration *pr_reg,
1025 	enum register_type register_type)
1026 {
1027 	struct se_portal_group *se_tpg = nacl->se_tpg;
1028 	char i_buf[PR_REG_ISID_ID_LEN];
1029 
1030 	memset(&i_buf[0], 0, PR_REG_ISID_ID_LEN);
1031 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1032 
1033 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
1034 		" Node: %s%s\n", tfo->get_fabric_name(), (register_type == REGISTER_AND_MOVE) ?
1035 		"_AND_MOVE" : (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ?
1036 		"_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
1037 		i_buf);
1038 	pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
1039 		 tfo->get_fabric_name(), tfo->tpg_get_wwn(se_tpg),
1040 		tfo->tpg_get_tag(se_tpg));
1041 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1042 		" Port(s)\n",  tfo->get_fabric_name(),
1043 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1044 		dev->transport->name);
1045 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1046 		" 0x%08x  APTPL: %d\n", tfo->get_fabric_name(),
1047 		pr_reg->pr_res_key, pr_reg->pr_res_generation,
1048 		pr_reg->pr_reg_aptpl);
1049 }
1050 
1051 static void __core_scsi3_add_registration(
1052 	struct se_device *dev,
1053 	struct se_node_acl *nacl,
1054 	struct t10_pr_registration *pr_reg,
1055 	enum register_type register_type,
1056 	int register_move)
1057 {
1058 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1059 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1060 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1061 	struct se_dev_entry *deve;
1062 
1063 	/*
1064 	 * Increment PRgeneration counter for struct se_device upon a successful
1065 	 * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1066 	 *
1067 	 * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1068 	 * action, the struct se_device->dev_reservation_lock will already be held,
1069 	 * so we do not call core_scsi3_pr_generation() which grabs the lock
1070 	 * for the REGISTER.
1071 	 */
1072 	pr_reg->pr_res_generation = (register_move) ?
1073 			dev->t10_pr.pr_generation++ :
1074 			core_scsi3_pr_generation(dev);
1075 
1076 	spin_lock(&pr_tmpl->registration_lock);
1077 	list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1078 
1079 	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1080 	spin_unlock(&pr_tmpl->registration_lock);
1081 	/*
1082 	 * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1083 	 */
1084 	if (!pr_reg->pr_reg_all_tg_pt || register_move)
1085 		goto out;
1086 	/*
1087 	 * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1088 	 * allocated in __core_scsi3_alloc_registration()
1089 	 */
1090 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1091 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1092 		struct se_node_acl *nacl_tmp = pr_reg_tmp->pr_reg_nacl;
1093 
1094 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1095 
1096 		pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1097 
1098 		spin_lock(&pr_tmpl->registration_lock);
1099 		list_add_tail(&pr_reg_tmp->pr_reg_list,
1100 			      &pr_tmpl->registration_list);
1101 
1102 		__core_scsi3_dump_registration(tfo, dev, nacl_tmp, pr_reg_tmp,
1103 					       register_type);
1104 		spin_unlock(&pr_tmpl->registration_lock);
1105 		/*
1106 		 * Drop configfs group dependency reference and deve->pr_kref
1107 		 * obtained from  __core_scsi3_alloc_registration() code.
1108 		 */
1109 		rcu_read_lock();
1110 		deve = pr_reg_tmp->pr_reg_deve;
1111 		if (deve) {
1112 			set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1113 			core_scsi3_lunacl_undepend_item(deve);
1114 			pr_reg_tmp->pr_reg_deve = NULL;
1115 		}
1116 		rcu_read_unlock();
1117 	}
1118 out:
1119 	/*
1120 	 * Drop deve->pr_kref obtained in __core_scsi3_do_alloc_registration()
1121 	 */
1122 	rcu_read_lock();
1123 	deve = pr_reg->pr_reg_deve;
1124 	if (deve) {
1125 		set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1126 		kref_put(&deve->pr_kref, target_pr_kref_release);
1127 		pr_reg->pr_reg_deve = NULL;
1128 	}
1129 	rcu_read_unlock();
1130 }
1131 
1132 static int core_scsi3_alloc_registration(
1133 	struct se_device *dev,
1134 	struct se_node_acl *nacl,
1135 	struct se_lun *lun,
1136 	struct se_dev_entry *deve,
1137 	u64 mapped_lun,
1138 	unsigned char *isid,
1139 	u64 sa_res_key,
1140 	int all_tg_pt,
1141 	int aptpl,
1142 	enum register_type register_type,
1143 	int register_move)
1144 {
1145 	struct t10_pr_registration *pr_reg;
1146 
1147 	pr_reg = __core_scsi3_alloc_registration(dev, nacl, lun, deve, mapped_lun,
1148 						 isid, sa_res_key, all_tg_pt,
1149 						 aptpl);
1150 	if (!pr_reg)
1151 		return -EPERM;
1152 
1153 	__core_scsi3_add_registration(dev, nacl, pr_reg,
1154 			register_type, register_move);
1155 	return 0;
1156 }
1157 
1158 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1159 	struct se_device *dev,
1160 	struct se_node_acl *nacl,
1161 	unsigned char *isid)
1162 {
1163 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1164 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1165 	struct se_portal_group *tpg;
1166 
1167 	spin_lock(&pr_tmpl->registration_lock);
1168 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1169 			&pr_tmpl->registration_list, pr_reg_list) {
1170 		/*
1171 		 * First look for a matching struct se_node_acl
1172 		 */
1173 		if (pr_reg->pr_reg_nacl != nacl)
1174 			continue;
1175 
1176 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1177 		/*
1178 		 * If this registration does NOT contain a fabric provided
1179 		 * ISID, then we have found a match.
1180 		 */
1181 		if (!pr_reg->isid_present_at_reg) {
1182 			/*
1183 			 * Determine if this SCSI device server requires that
1184 			 * SCSI Intiatior TransportID w/ ISIDs is enforced
1185 			 * for fabric modules (iSCSI) requiring them.
1186 			 */
1187 			if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1188 				if (dev->dev_attrib.enforce_pr_isids)
1189 					continue;
1190 			}
1191 			atomic_inc_mb(&pr_reg->pr_res_holders);
1192 			spin_unlock(&pr_tmpl->registration_lock);
1193 			return pr_reg;
1194 		}
1195 		/*
1196 		 * If the *pr_reg contains a fabric defined ISID for multi-value
1197 		 * SCSI Initiator Port TransportIDs, then we expect a valid
1198 		 * matching ISID to be provided by the local SCSI Initiator Port.
1199 		 */
1200 		if (!isid)
1201 			continue;
1202 		if (strcmp(isid, pr_reg->pr_reg_isid))
1203 			continue;
1204 
1205 		atomic_inc_mb(&pr_reg->pr_res_holders);
1206 		spin_unlock(&pr_tmpl->registration_lock);
1207 		return pr_reg;
1208 	}
1209 	spin_unlock(&pr_tmpl->registration_lock);
1210 
1211 	return NULL;
1212 }
1213 
1214 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1215 	struct se_device *dev,
1216 	struct se_node_acl *nacl,
1217 	struct se_session *sess)
1218 {
1219 	struct se_portal_group *tpg = nacl->se_tpg;
1220 	unsigned char buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
1221 
1222 	if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1223 		memset(&buf[0], 0, PR_REG_ISID_LEN);
1224 		tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1225 					PR_REG_ISID_LEN);
1226 		isid_ptr = &buf[0];
1227 	}
1228 
1229 	return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1230 }
1231 
1232 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1233 {
1234 	atomic_dec_mb(&pr_reg->pr_res_holders);
1235 }
1236 
1237 static int core_scsi3_check_implicit_release(
1238 	struct se_device *dev,
1239 	struct t10_pr_registration *pr_reg)
1240 {
1241 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1242 	struct t10_pr_registration *pr_res_holder;
1243 	int ret = 0;
1244 
1245 	spin_lock(&dev->dev_reservation_lock);
1246 	pr_res_holder = dev->dev_pr_res_holder;
1247 	if (!pr_res_holder) {
1248 		spin_unlock(&dev->dev_reservation_lock);
1249 		return ret;
1250 	}
1251 	if (pr_res_holder == pr_reg) {
1252 		/*
1253 		 * Perform an implicit RELEASE if the registration that
1254 		 * is being released is holding the reservation.
1255 		 *
1256 		 * From spc4r17, section 5.7.11.1:
1257 		 *
1258 		 * e) If the I_T nexus is the persistent reservation holder
1259 		 *    and the persistent reservation is not an all registrants
1260 		 *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1261 		 *    service action or REGISTER AND  IGNORE EXISTING KEY
1262 		 *    service action with the SERVICE ACTION RESERVATION KEY
1263 		 *    field set to zero (see 5.7.11.3).
1264 		 */
1265 		__core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0, 1);
1266 		ret = 1;
1267 		/*
1268 		 * For 'All Registrants' reservation types, all existing
1269 		 * registrations are still processed as reservation holders
1270 		 * in core_scsi3_pr_seq_non_holder() after the initial
1271 		 * reservation holder is implicitly released here.
1272 		 */
1273 	} else if (pr_reg->pr_reg_all_tg_pt &&
1274 		  (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1275 			  pr_reg->pr_reg_nacl->initiatorname)) &&
1276 		  (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1277 		pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1278 			" UNREGISTER while existing reservation with matching"
1279 			" key 0x%016Lx is present from another SCSI Initiator"
1280 			" Port\n", pr_reg->pr_res_key);
1281 		ret = -EPERM;
1282 	}
1283 	spin_unlock(&dev->dev_reservation_lock);
1284 
1285 	return ret;
1286 }
1287 
1288 /*
1289  * Called with struct t10_reservation->registration_lock held.
1290  */
1291 static void __core_scsi3_free_registration(
1292 	struct se_device *dev,
1293 	struct t10_pr_registration *pr_reg,
1294 	struct list_head *preempt_and_abort_list,
1295 	int dec_holders)
1296 	__releases(&pr_tmpl->registration_lock)
1297 	__acquires(&pr_tmpl->registration_lock)
1298 {
1299 	const struct target_core_fabric_ops *tfo =
1300 			pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1301 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1302 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1303 	struct se_dev_entry *deve;
1304 	char i_buf[PR_REG_ISID_ID_LEN];
1305 
1306 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1307 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1308 
1309 	if (!list_empty(&pr_reg->pr_reg_list))
1310 		list_del(&pr_reg->pr_reg_list);
1311 	/*
1312 	 * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1313 	 * so call core_scsi3_put_pr_reg() to decrement our reference.
1314 	 */
1315 	if (dec_holders)
1316 		core_scsi3_put_pr_reg(pr_reg);
1317 
1318 	spin_unlock(&pr_tmpl->registration_lock);
1319 	/*
1320 	 * Wait until all reference from any other I_T nexuses for this
1321 	 * *pr_reg have been released.  Because list_del() is called above,
1322 	 * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1323 	 * count back to zero, and we release *pr_reg.
1324 	 */
1325 	while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1326 		pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1327 				tfo->get_fabric_name());
1328 		cpu_relax();
1329 	}
1330 
1331 	rcu_read_lock();
1332 	deve = target_nacl_find_deve(nacl, pr_reg->pr_res_mapped_lun);
1333 	if (deve)
1334 		clear_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1335 	rcu_read_unlock();
1336 
1337 	spin_lock(&pr_tmpl->registration_lock);
1338 	pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1339 		" Node: %s%s\n", tfo->get_fabric_name(),
1340 		pr_reg->pr_reg_nacl->initiatorname,
1341 		i_buf);
1342 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1343 		" Port(s)\n", tfo->get_fabric_name(),
1344 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1345 		dev->transport->name);
1346 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1347 		" 0x%08x\n", tfo->get_fabric_name(), pr_reg->pr_res_key,
1348 		pr_reg->pr_res_generation);
1349 
1350 	if (!preempt_and_abort_list) {
1351 		pr_reg->pr_reg_deve = NULL;
1352 		pr_reg->pr_reg_nacl = NULL;
1353 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1354 		return;
1355 	}
1356 	/*
1357 	 * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1358 	 * are released once the ABORT_TASK_SET has completed..
1359 	 */
1360 	list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1361 }
1362 
1363 void core_scsi3_free_pr_reg_from_nacl(
1364 	struct se_device *dev,
1365 	struct se_node_acl *nacl)
1366 {
1367 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1368 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1369 	bool free_reg = false;
1370 	/*
1371 	 * If the passed se_node_acl matches the reservation holder,
1372 	 * release the reservation.
1373 	 */
1374 	spin_lock(&dev->dev_reservation_lock);
1375 	pr_res_holder = dev->dev_pr_res_holder;
1376 	if ((pr_res_holder != NULL) &&
1377 	    (pr_res_holder->pr_reg_nacl == nacl)) {
1378 		__core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0, 1);
1379 		free_reg = true;
1380 	}
1381 	spin_unlock(&dev->dev_reservation_lock);
1382 	/*
1383 	 * Release any registration associated with the struct se_node_acl.
1384 	 */
1385 	spin_lock(&pr_tmpl->registration_lock);
1386 	if (pr_res_holder && free_reg)
1387 		__core_scsi3_free_registration(dev, pr_res_holder, NULL, 0);
1388 
1389 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1390 			&pr_tmpl->registration_list, pr_reg_list) {
1391 
1392 		if (pr_reg->pr_reg_nacl != nacl)
1393 			continue;
1394 
1395 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1396 	}
1397 	spin_unlock(&pr_tmpl->registration_lock);
1398 }
1399 
1400 void core_scsi3_free_all_registrations(
1401 	struct se_device *dev)
1402 {
1403 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1404 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1405 
1406 	spin_lock(&dev->dev_reservation_lock);
1407 	pr_res_holder = dev->dev_pr_res_holder;
1408 	if (pr_res_holder != NULL) {
1409 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1410 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
1411 						  pr_res_holder, 0, 0);
1412 	}
1413 	spin_unlock(&dev->dev_reservation_lock);
1414 
1415 	spin_lock(&pr_tmpl->registration_lock);
1416 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1417 			&pr_tmpl->registration_list, pr_reg_list) {
1418 
1419 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1420 	}
1421 	spin_unlock(&pr_tmpl->registration_lock);
1422 
1423 	spin_lock(&pr_tmpl->aptpl_reg_lock);
1424 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1425 				pr_reg_aptpl_list) {
1426 		list_del(&pr_reg->pr_reg_aptpl_list);
1427 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1428 	}
1429 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
1430 }
1431 
1432 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1433 {
1434 	return target_depend_item(&tpg->tpg_group.cg_item);
1435 }
1436 
1437 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1438 {
1439 	target_undepend_item(&tpg->tpg_group.cg_item);
1440 	atomic_dec_mb(&tpg->tpg_pr_ref_count);
1441 }
1442 
1443 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1444 {
1445 	if (nacl->dynamic_node_acl)
1446 		return 0;
1447 	return target_depend_item(&nacl->acl_group.cg_item);
1448 }
1449 
1450 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1451 {
1452 	if (!nacl->dynamic_node_acl)
1453 		target_undepend_item(&nacl->acl_group.cg_item);
1454 	atomic_dec_mb(&nacl->acl_pr_ref_count);
1455 }
1456 
1457 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1458 {
1459 	struct se_lun_acl *lun_acl;
1460 	struct se_node_acl *nacl;
1461 	struct se_portal_group *tpg;
1462 	/*
1463 	 * For nacl->dynamic_node_acl=1
1464 	 */
1465 	lun_acl = rcu_dereference_check(se_deve->se_lun_acl,
1466 				atomic_read(&se_deve->pr_kref.refcount) != 0);
1467 	if (!lun_acl)
1468 		return 0;
1469 
1470 	nacl = lun_acl->se_lun_nacl;
1471 	tpg = nacl->se_tpg;
1472 
1473 	return target_depend_item(&lun_acl->se_lun_group.cg_item);
1474 }
1475 
1476 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1477 {
1478 	struct se_lun_acl *lun_acl;
1479 	struct se_node_acl *nacl;
1480 	struct se_portal_group *tpg;
1481 	/*
1482 	 * For nacl->dynamic_node_acl=1
1483 	 */
1484 	lun_acl = rcu_dereference_check(se_deve->se_lun_acl,
1485 				atomic_read(&se_deve->pr_kref.refcount) != 0);
1486 	if (!lun_acl) {
1487 		kref_put(&se_deve->pr_kref, target_pr_kref_release);
1488 		return;
1489 	}
1490 	nacl = lun_acl->se_lun_nacl;
1491 	tpg = nacl->se_tpg;
1492 
1493 	target_undepend_item(&lun_acl->se_lun_group.cg_item);
1494 	kref_put(&se_deve->pr_kref, target_pr_kref_release);
1495 }
1496 
1497 static sense_reason_t
1498 core_scsi3_decode_spec_i_port(
1499 	struct se_cmd *cmd,
1500 	struct se_portal_group *tpg,
1501 	unsigned char *l_isid,
1502 	u64 sa_res_key,
1503 	int all_tg_pt,
1504 	int aptpl)
1505 {
1506 	struct se_device *dev = cmd->se_dev;
1507 	struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1508 	struct se_session *se_sess = cmd->se_sess;
1509 	struct se_node_acl *dest_node_acl = NULL;
1510 	struct se_dev_entry *dest_se_deve = NULL;
1511 	struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1512 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1513 	LIST_HEAD(tid_dest_list);
1514 	struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1515 	unsigned char *buf, *ptr, proto_ident;
1516 	const unsigned char *i_str = NULL;
1517 	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
1518 	sense_reason_t ret;
1519 	u32 tpdl, tid_len = 0;
1520 	u32 dest_rtpi = 0;
1521 
1522 	/*
1523 	 * Allocate a struct pr_transport_id_holder and setup the
1524 	 * local_node_acl pointer and add to struct list_head tid_dest_list
1525 	 * for add registration processing in the loop of tid_dest_list below.
1526 	 */
1527 	tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1528 	if (!tidh_new) {
1529 		pr_err("Unable to allocate tidh_new\n");
1530 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1531 	}
1532 	INIT_LIST_HEAD(&tidh_new->dest_list);
1533 	tidh_new->dest_tpg = tpg;
1534 	tidh_new->dest_node_acl = se_sess->se_node_acl;
1535 
1536 	local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1537 				se_sess->se_node_acl, cmd->se_lun,
1538 				NULL, cmd->orig_fe_lun, l_isid,
1539 				sa_res_key, all_tg_pt, aptpl);
1540 	if (!local_pr_reg) {
1541 		kfree(tidh_new);
1542 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1543 	}
1544 	tidh_new->dest_pr_reg = local_pr_reg;
1545 	/*
1546 	 * The local I_T nexus does not hold any configfs dependances,
1547 	 * so we set tidh_new->dest_se_deve to NULL to prevent the
1548 	 * configfs_undepend_item() calls in the tid_dest_list loops below.
1549 	 */
1550 	tidh_new->dest_se_deve = NULL;
1551 	list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1552 
1553 	if (cmd->data_length < 28) {
1554 		pr_warn("SPC-PR: Received PR OUT parameter list"
1555 			" length too small: %u\n", cmd->data_length);
1556 		ret = TCM_INVALID_PARAMETER_LIST;
1557 		goto out;
1558 	}
1559 
1560 	buf = transport_kmap_data_sg(cmd);
1561 	if (!buf) {
1562 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1563 		goto out;
1564 	}
1565 
1566 	/*
1567 	 * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1568 	 * first extract TransportID Parameter Data Length, and make sure
1569 	 * the value matches up to the SCSI expected data transfer length.
1570 	 */
1571 	tpdl = (buf[24] & 0xff) << 24;
1572 	tpdl |= (buf[25] & 0xff) << 16;
1573 	tpdl |= (buf[26] & 0xff) << 8;
1574 	tpdl |= buf[27] & 0xff;
1575 
1576 	if ((tpdl + 28) != cmd->data_length) {
1577 		pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1578 			" does not equal CDB data_length: %u\n", tpdl,
1579 			cmd->data_length);
1580 		ret = TCM_INVALID_PARAMETER_LIST;
1581 		goto out_unmap;
1582 	}
1583 	/*
1584 	 * Start processing the received transport IDs using the
1585 	 * receiving I_T Nexus portal's fabric dependent methods to
1586 	 * obtain the SCSI Initiator Port/Device Identifiers.
1587 	 */
1588 	ptr = &buf[28];
1589 
1590 	while (tpdl > 0) {
1591 		struct se_lun *dest_lun, *tmp_lun;
1592 
1593 		proto_ident = (ptr[0] & 0x0f);
1594 		dest_tpg = NULL;
1595 
1596 		spin_lock(&dev->se_port_lock);
1597 		list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
1598 			tmp_tpg = tmp_lun->lun_tpg;
1599 
1600 			/*
1601 			 * Look for the matching proto_ident provided by
1602 			 * the received TransportID
1603 			 */
1604 			if (tmp_tpg->proto_id != proto_ident)
1605 				continue;
1606 			dest_rtpi = tmp_lun->lun_rtpi;
1607 
1608 			i_str = target_parse_pr_out_transport_id(tmp_tpg,
1609 					(const char *)ptr, &tid_len, &iport_ptr);
1610 			if (!i_str)
1611 				continue;
1612 
1613 			atomic_inc_mb(&tmp_tpg->tpg_pr_ref_count);
1614 			spin_unlock(&dev->se_port_lock);
1615 
1616 			if (core_scsi3_tpg_depend_item(tmp_tpg)) {
1617 				pr_err(" core_scsi3_tpg_depend_item()"
1618 					" for tmp_tpg\n");
1619 				atomic_dec_mb(&tmp_tpg->tpg_pr_ref_count);
1620 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1621 				goto out_unmap;
1622 			}
1623 			/*
1624 			 * Locate the destination initiator ACL to be registered
1625 			 * from the decoded fabric module specific TransportID
1626 			 * at *i_str.
1627 			 */
1628 			mutex_lock(&tmp_tpg->acl_node_mutex);
1629 			dest_node_acl = __core_tpg_get_initiator_node_acl(
1630 						tmp_tpg, i_str);
1631 			if (dest_node_acl)
1632 				atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
1633 			mutex_unlock(&tmp_tpg->acl_node_mutex);
1634 
1635 			if (!dest_node_acl) {
1636 				core_scsi3_tpg_undepend_item(tmp_tpg);
1637 				spin_lock(&dev->se_port_lock);
1638 				continue;
1639 			}
1640 
1641 			if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
1642 				pr_err("configfs_depend_item() failed"
1643 					" for dest_node_acl->acl_group\n");
1644 				atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
1645 				core_scsi3_tpg_undepend_item(tmp_tpg);
1646 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1647 				goto out_unmap;
1648 			}
1649 
1650 			dest_tpg = tmp_tpg;
1651 			pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1652 				" %s Port RTPI: %hu\n",
1653 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1654 				dest_node_acl->initiatorname, dest_rtpi);
1655 
1656 			spin_lock(&dev->se_port_lock);
1657 			break;
1658 		}
1659 		spin_unlock(&dev->se_port_lock);
1660 
1661 		if (!dest_tpg) {
1662 			pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1663 					" dest_tpg\n");
1664 			ret = TCM_INVALID_PARAMETER_LIST;
1665 			goto out_unmap;
1666 		}
1667 
1668 		pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1669 			" tid_len: %d for %s + %s\n",
1670 			dest_tpg->se_tpg_tfo->get_fabric_name(), cmd->data_length,
1671 			tpdl, tid_len, i_str, iport_ptr);
1672 
1673 		if (tid_len > tpdl) {
1674 			pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1675 				" %u for Transport ID: %s\n", tid_len, ptr);
1676 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1677 			core_scsi3_tpg_undepend_item(dest_tpg);
1678 			ret = TCM_INVALID_PARAMETER_LIST;
1679 			goto out_unmap;
1680 		}
1681 		/*
1682 		 * Locate the desintation struct se_dev_entry pointer for matching
1683 		 * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1684 		 * Target Port.
1685 		 */
1686 		dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1687 					dest_rtpi);
1688 		if (!dest_se_deve) {
1689 			pr_err("Unable to locate %s dest_se_deve"
1690 				" from destination RTPI: %hu\n",
1691 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1692 				dest_rtpi);
1693 
1694 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1695 			core_scsi3_tpg_undepend_item(dest_tpg);
1696 			ret = TCM_INVALID_PARAMETER_LIST;
1697 			goto out_unmap;
1698 		}
1699 
1700 		if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
1701 			pr_err("core_scsi3_lunacl_depend_item()"
1702 					" failed\n");
1703 			kref_put(&dest_se_deve->pr_kref, target_pr_kref_release);
1704 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1705 			core_scsi3_tpg_undepend_item(dest_tpg);
1706 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1707 			goto out_unmap;
1708 		}
1709 
1710 		pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1711 			" dest_se_deve mapped_lun: %llu\n",
1712 			dest_tpg->se_tpg_tfo->get_fabric_name(),
1713 			dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1714 
1715 		/*
1716 		 * Skip any TransportIDs that already have a registration for
1717 		 * this target port.
1718 		 */
1719 		pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1720 					iport_ptr);
1721 		if (pr_reg_e) {
1722 			core_scsi3_put_pr_reg(pr_reg_e);
1723 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1724 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1725 			core_scsi3_tpg_undepend_item(dest_tpg);
1726 			ptr += tid_len;
1727 			tpdl -= tid_len;
1728 			tid_len = 0;
1729 			continue;
1730 		}
1731 		/*
1732 		 * Allocate a struct pr_transport_id_holder and setup
1733 		 * the dest_node_acl and dest_se_deve pointers for the
1734 		 * loop below.
1735 		 */
1736 		tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1737 				GFP_KERNEL);
1738 		if (!tidh_new) {
1739 			pr_err("Unable to allocate tidh_new\n");
1740 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1741 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1742 			core_scsi3_tpg_undepend_item(dest_tpg);
1743 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1744 			goto out_unmap;
1745 		}
1746 		INIT_LIST_HEAD(&tidh_new->dest_list);
1747 		tidh_new->dest_tpg = dest_tpg;
1748 		tidh_new->dest_node_acl = dest_node_acl;
1749 		tidh_new->dest_se_deve = dest_se_deve;
1750 
1751 		/*
1752 		 * Allocate, but do NOT add the registration for the
1753 		 * TransportID referenced SCSI Initiator port.  This
1754 		 * done because of the following from spc4r17 in section
1755 		 * 6.14.3 wrt SPEC_I_PT:
1756 		 *
1757 		 * "If a registration fails for any initiator port (e.g., if th
1758 		 * logical unit does not have enough resources available to
1759 		 * hold the registration information), no registrations shall be
1760 		 * made, and the command shall be terminated with
1761 		 * CHECK CONDITION status."
1762 		 *
1763 		 * That means we call __core_scsi3_alloc_registration() here,
1764 		 * and then call __core_scsi3_add_registration() in the
1765 		 * 2nd loop which will never fail.
1766 		 */
1767 		dest_lun = rcu_dereference_check(dest_se_deve->se_lun,
1768 				atomic_read(&dest_se_deve->pr_kref.refcount) != 0);
1769 
1770 		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1771 					dest_node_acl, dest_lun, dest_se_deve,
1772 					dest_se_deve->mapped_lun, iport_ptr,
1773 					sa_res_key, all_tg_pt, aptpl);
1774 		if (!dest_pr_reg) {
1775 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1776 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1777 			core_scsi3_tpg_undepend_item(dest_tpg);
1778 			kfree(tidh_new);
1779 			ret = TCM_INVALID_PARAMETER_LIST;
1780 			goto out_unmap;
1781 		}
1782 		tidh_new->dest_pr_reg = dest_pr_reg;
1783 		list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1784 
1785 		ptr += tid_len;
1786 		tpdl -= tid_len;
1787 		tid_len = 0;
1788 
1789 	}
1790 
1791 	transport_kunmap_data_sg(cmd);
1792 
1793 	/*
1794 	 * Go ahead and create a registrations from tid_dest_list for the
1795 	 * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1796 	 * and dest_se_deve.
1797 	 *
1798 	 * The SA Reservation Key from the PROUT is set for the
1799 	 * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1800 	 * means that the TransportID Initiator port will be
1801 	 * registered on all of the target ports in the SCSI target device
1802 	 * ALL_TG_PT=0 means the registration will only be for the
1803 	 * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1804 	 * was received.
1805 	 */
1806 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1807 		dest_tpg = tidh->dest_tpg;
1808 		dest_node_acl = tidh->dest_node_acl;
1809 		dest_se_deve = tidh->dest_se_deve;
1810 		dest_pr_reg = tidh->dest_pr_reg;
1811 
1812 		list_del(&tidh->dest_list);
1813 		kfree(tidh);
1814 
1815 		memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1816 		core_pr_dump_initiator_port(dest_pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1817 
1818 		__core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1819 					dest_pr_reg, 0, 0);
1820 
1821 		pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1822 			" registered Transport ID for Node: %s%s Mapped LUN:"
1823 			" %llu\n", dest_tpg->se_tpg_tfo->get_fabric_name(),
1824 			dest_node_acl->initiatorname, i_buf, (dest_se_deve) ?
1825 			dest_se_deve->mapped_lun : 0);
1826 
1827 		if (!dest_se_deve) {
1828 			kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
1829 				 target_pr_kref_release);
1830 			continue;
1831 		}
1832 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1833 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1834 		core_scsi3_tpg_undepend_item(dest_tpg);
1835 	}
1836 
1837 	return 0;
1838 out_unmap:
1839 	transport_kunmap_data_sg(cmd);
1840 out:
1841 	/*
1842 	 * For the failure case, release everything from tid_dest_list
1843 	 * including *dest_pr_reg and the configfs dependances..
1844 	 */
1845 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1846 		dest_tpg = tidh->dest_tpg;
1847 		dest_node_acl = tidh->dest_node_acl;
1848 		dest_se_deve = tidh->dest_se_deve;
1849 		dest_pr_reg = tidh->dest_pr_reg;
1850 
1851 		list_del(&tidh->dest_list);
1852 		kfree(tidh);
1853 		/*
1854 		 * Release any extra ALL_TG_PT=1 registrations for
1855 		 * the SPEC_I_PT=1 case.
1856 		 */
1857 		list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1858 				&dest_pr_reg->pr_reg_atp_list,
1859 				pr_reg_atp_mem_list) {
1860 			list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1861 			core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1862 			kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1863 		}
1864 
1865 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1866 
1867 		if (!dest_se_deve) {
1868 			kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
1869 				 target_pr_kref_release);
1870 			continue;
1871 		}
1872 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1873 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1874 		core_scsi3_tpg_undepend_item(dest_tpg);
1875 	}
1876 	return ret;
1877 }
1878 
1879 static int core_scsi3_update_aptpl_buf(
1880 	struct se_device *dev,
1881 	unsigned char *buf,
1882 	u32 pr_aptpl_buf_len)
1883 {
1884 	struct se_portal_group *tpg;
1885 	struct t10_pr_registration *pr_reg;
1886 	unsigned char tmp[512], isid_buf[32];
1887 	ssize_t len = 0;
1888 	int reg_count = 0;
1889 	int ret = 0;
1890 
1891 	spin_lock(&dev->dev_reservation_lock);
1892 	spin_lock(&dev->t10_pr.registration_lock);
1893 	/*
1894 	 * Walk the registration list..
1895 	 */
1896 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
1897 			pr_reg_list) {
1898 
1899 		tmp[0] = '\0';
1900 		isid_buf[0] = '\0';
1901 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1902 		/*
1903 		 * Write out any ISID value to APTPL metadata that was included
1904 		 * in the original registration.
1905 		 */
1906 		if (pr_reg->isid_present_at_reg)
1907 			snprintf(isid_buf, 32, "initiator_sid=%s\n",
1908 					pr_reg->pr_reg_isid);
1909 		/*
1910 		 * Include special metadata if the pr_reg matches the
1911 		 * reservation holder.
1912 		 */
1913 		if (dev->dev_pr_res_holder == pr_reg) {
1914 			snprintf(tmp, 512, "PR_REG_START: %d"
1915 				"\ninitiator_fabric=%s\n"
1916 				"initiator_node=%s\n%s"
1917 				"sa_res_key=%llu\n"
1918 				"res_holder=1\nres_type=%02x\n"
1919 				"res_scope=%02x\nres_all_tg_pt=%d\n"
1920 				"mapped_lun=%llu\n", reg_count,
1921 				tpg->se_tpg_tfo->get_fabric_name(),
1922 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1923 				pr_reg->pr_res_key, pr_reg->pr_res_type,
1924 				pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1925 				pr_reg->pr_res_mapped_lun);
1926 		} else {
1927 			snprintf(tmp, 512, "PR_REG_START: %d\n"
1928 				"initiator_fabric=%s\ninitiator_node=%s\n%s"
1929 				"sa_res_key=%llu\nres_holder=0\n"
1930 				"res_all_tg_pt=%d\nmapped_lun=%llu\n",
1931 				reg_count, tpg->se_tpg_tfo->get_fabric_name(),
1932 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1933 				pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1934 				pr_reg->pr_res_mapped_lun);
1935 		}
1936 
1937 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1938 			pr_err("Unable to update renaming APTPL metadata,"
1939 			       " reallocating larger buffer\n");
1940 			ret = -EMSGSIZE;
1941 			goto out;
1942 		}
1943 		len += sprintf(buf+len, "%s", tmp);
1944 
1945 		/*
1946 		 * Include information about the associated SCSI target port.
1947 		 */
1948 		snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1949 			"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%llu\nPR_REG_END:"
1950 			" %d\n", tpg->se_tpg_tfo->get_fabric_name(),
1951 			tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1952 			tpg->se_tpg_tfo->tpg_get_tag(tpg),
1953 			pr_reg->tg_pt_sep_rtpi, pr_reg->pr_aptpl_target_lun,
1954 			reg_count);
1955 
1956 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1957 			pr_err("Unable to update renaming APTPL metadata,"
1958 			       " reallocating larger buffer\n");
1959 			ret = -EMSGSIZE;
1960 			goto out;
1961 		}
1962 		len += sprintf(buf+len, "%s", tmp);
1963 		reg_count++;
1964 	}
1965 
1966 	if (!reg_count)
1967 		len += sprintf(buf+len, "No Registrations or Reservations");
1968 
1969 out:
1970 	spin_unlock(&dev->t10_pr.registration_lock);
1971 	spin_unlock(&dev->dev_reservation_lock);
1972 
1973 	return ret;
1974 }
1975 
1976 static int __core_scsi3_write_aptpl_to_file(
1977 	struct se_device *dev,
1978 	unsigned char *buf)
1979 {
1980 	struct t10_wwn *wwn = &dev->t10_wwn;
1981 	struct file *file;
1982 	int flags = O_RDWR | O_CREAT | O_TRUNC;
1983 	char path[512];
1984 	u32 pr_aptpl_buf_len;
1985 	int ret;
1986 
1987 	memset(path, 0, 512);
1988 
1989 	if (strlen(&wwn->unit_serial[0]) >= 512) {
1990 		pr_err("WWN value for struct se_device does not fit"
1991 			" into path buffer\n");
1992 		return -EMSGSIZE;
1993 	}
1994 
1995 	snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
1996 	file = filp_open(path, flags, 0600);
1997 	if (IS_ERR(file)) {
1998 		pr_err("filp_open(%s) for APTPL metadata"
1999 			" failed\n", path);
2000 		return PTR_ERR(file);
2001 	}
2002 
2003 	pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
2004 
2005 	ret = kernel_write(file, buf, pr_aptpl_buf_len, 0);
2006 
2007 	if (ret < 0)
2008 		pr_debug("Error writing APTPL metadata file: %s\n", path);
2009 	fput(file);
2010 
2011 	return (ret < 0) ? -EIO : 0;
2012 }
2013 
2014 /*
2015  * Clear the APTPL metadata if APTPL has been disabled, otherwise
2016  * write out the updated metadata to struct file for this SCSI device.
2017  */
2018 static sense_reason_t core_scsi3_update_and_write_aptpl(struct se_device *dev, bool aptpl)
2019 {
2020 	unsigned char *buf;
2021 	int rc, len = PR_APTPL_BUF_LEN;
2022 
2023 	if (!aptpl) {
2024 		char *null_buf = "No Registrations or Reservations\n";
2025 
2026 		rc = __core_scsi3_write_aptpl_to_file(dev, null_buf);
2027 		dev->t10_pr.pr_aptpl_active = 0;
2028 		pr_debug("SPC-3 PR: Set APTPL Bit Deactivated\n");
2029 
2030 		if (rc)
2031 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2032 
2033 		return 0;
2034 	}
2035 retry:
2036 	buf = vzalloc(len);
2037 	if (!buf)
2038 		return TCM_OUT_OF_RESOURCES;
2039 
2040 	rc = core_scsi3_update_aptpl_buf(dev, buf, len);
2041 	if (rc < 0) {
2042 		vfree(buf);
2043 		len *= 2;
2044 		goto retry;
2045 	}
2046 
2047 	rc = __core_scsi3_write_aptpl_to_file(dev, buf);
2048 	if (rc != 0) {
2049 		pr_err("SPC-3 PR: Could not update APTPL\n");
2050 		vfree(buf);
2051 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2052 	}
2053 	dev->t10_pr.pr_aptpl_active = 1;
2054 	vfree(buf);
2055 	pr_debug("SPC-3 PR: Set APTPL Bit Activated\n");
2056 	return 0;
2057 }
2058 
2059 static sense_reason_t
2060 core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
2061 		bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type)
2062 {
2063 	struct se_session *se_sess = cmd->se_sess;
2064 	struct se_device *dev = cmd->se_dev;
2065 	struct se_lun *se_lun = cmd->se_lun;
2066 	struct se_portal_group *se_tpg;
2067 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp;
2068 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2069 	unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2070 	sense_reason_t ret = TCM_NO_SENSE;
2071 	int pr_holder = 0, type;
2072 
2073 	if (!se_sess || !se_lun) {
2074 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2075 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2076 	}
2077 	se_tpg = se_sess->se_tpg;
2078 
2079 	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2080 		memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2081 		se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2082 				PR_REG_ISID_LEN);
2083 		isid_ptr = &isid_buf[0];
2084 	}
2085 	/*
2086 	 * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2087 	 */
2088 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2089 	if (!pr_reg) {
2090 		if (res_key) {
2091 			pr_warn("SPC-3 PR: Reservation Key non-zero"
2092 				" for SA REGISTER, returning CONFLICT\n");
2093 			return TCM_RESERVATION_CONFLICT;
2094 		}
2095 		/*
2096 		 * Do nothing but return GOOD status.
2097 		 */
2098 		if (!sa_res_key)
2099 			return 0;
2100 
2101 		if (!spec_i_pt) {
2102 			/*
2103 			 * Perform the Service Action REGISTER on the Initiator
2104 			 * Port Endpoint that the PRO was received from on the
2105 			 * Logical Unit of the SCSI device server.
2106 			 */
2107 			if (core_scsi3_alloc_registration(cmd->se_dev,
2108 					se_sess->se_node_acl, cmd->se_lun,
2109 					NULL, cmd->orig_fe_lun, isid_ptr,
2110 					sa_res_key, all_tg_pt, aptpl,
2111 					register_type, 0)) {
2112 				pr_err("Unable to allocate"
2113 					" struct t10_pr_registration\n");
2114 				return TCM_INVALID_PARAMETER_LIST;
2115 			}
2116 		} else {
2117 			/*
2118 			 * Register both the Initiator port that received
2119 			 * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2120 			 * TransportID from Parameter list and loop through
2121 			 * fabric dependent parameter list while calling
2122 			 * logic from of core_scsi3_alloc_registration() for
2123 			 * each TransportID provided SCSI Initiator Port/Device
2124 			 */
2125 			ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2126 					isid_ptr, sa_res_key, all_tg_pt, aptpl);
2127 			if (ret != 0)
2128 				return ret;
2129 		}
2130 		return core_scsi3_update_and_write_aptpl(dev, aptpl);
2131 	}
2132 
2133 	/* ok, existing registration */
2134 
2135 	if ((register_type == REGISTER) && (res_key != pr_reg->pr_res_key)) {
2136 		pr_err("SPC-3 PR REGISTER: Received"
2137 		       " res_key: 0x%016Lx does not match"
2138 		       " existing SA REGISTER res_key:"
2139 		       " 0x%016Lx\n", res_key,
2140 		       pr_reg->pr_res_key);
2141 		ret = TCM_RESERVATION_CONFLICT;
2142 		goto out;
2143 	}
2144 
2145 	if (spec_i_pt) {
2146 		pr_err("SPC-3 PR REGISTER: SPEC_I_PT"
2147 			" set on a registered nexus\n");
2148 		ret = TCM_INVALID_PARAMETER_LIST;
2149 		goto out;
2150 	}
2151 
2152 	/*
2153 	 * An existing ALL_TG_PT=1 registration being released
2154 	 * must also set ALL_TG_PT=1 in the incoming PROUT.
2155 	 */
2156 	if (pr_reg->pr_reg_all_tg_pt && !all_tg_pt) {
2157 		pr_err("SPC-3 PR REGISTER: ALL_TG_PT=1"
2158 			" registration exists, but ALL_TG_PT=1 bit not"
2159 			" present in received PROUT\n");
2160 		ret = TCM_INVALID_CDB_FIELD;
2161 		goto out;
2162 	}
2163 
2164 	/*
2165 	 * sa_res_key=1 Change Reservation Key for registered I_T Nexus.
2166 	 */
2167 	if (sa_res_key) {
2168 		/*
2169 		 * Increment PRgeneration counter for struct se_device"
2170 		 * upon a successful REGISTER, see spc4r17 section 6.3.2
2171 		 * READ_KEYS service action.
2172 		 */
2173 		pr_reg->pr_res_generation = core_scsi3_pr_generation(cmd->se_dev);
2174 		pr_reg->pr_res_key = sa_res_key;
2175 		pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2176 			 " Key for %s to: 0x%016Lx PRgeneration:"
2177 			 " 0x%08x\n", cmd->se_tfo->get_fabric_name(),
2178 			 (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ? "_AND_IGNORE_EXISTING_KEY" : "",
2179 			 pr_reg->pr_reg_nacl->initiatorname,
2180 			 pr_reg->pr_res_key, pr_reg->pr_res_generation);
2181 
2182 	} else {
2183 		/*
2184 		 * sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
2185 		 */
2186 		type = pr_reg->pr_res_type;
2187 		pr_holder = core_scsi3_check_implicit_release(cmd->se_dev,
2188 							      pr_reg);
2189 		if (pr_holder < 0) {
2190 			ret = TCM_RESERVATION_CONFLICT;
2191 			goto out;
2192 		}
2193 
2194 		spin_lock(&pr_tmpl->registration_lock);
2195 		/*
2196 		 * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2197 		 * and matching pr_res_key.
2198 		 */
2199 		if (pr_reg->pr_reg_all_tg_pt) {
2200 			list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2201 					&pr_tmpl->registration_list,
2202 					pr_reg_list) {
2203 
2204 				if (!pr_reg_p->pr_reg_all_tg_pt)
2205 					continue;
2206 				if (pr_reg_p->pr_res_key != res_key)
2207 					continue;
2208 				if (pr_reg == pr_reg_p)
2209 					continue;
2210 				if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2211 					   pr_reg_p->pr_reg_nacl->initiatorname))
2212 					continue;
2213 
2214 				__core_scsi3_free_registration(dev,
2215 						pr_reg_p, NULL, 0);
2216 			}
2217 		}
2218 
2219 		/*
2220 		 * Release the calling I_T Nexus registration now..
2221 		 */
2222 		__core_scsi3_free_registration(cmd->se_dev, pr_reg, NULL, 1);
2223 		pr_reg = NULL;
2224 
2225 		/*
2226 		 * From spc4r17, section 5.7.11.3 Unregistering
2227 		 *
2228 		 * If the persistent reservation is a registrants only
2229 		 * type, the device server shall establish a unit
2230 		 * attention condition for the initiator port associated
2231 		 * with every registered I_T nexus except for the I_T
2232 		 * nexus on which the PERSISTENT RESERVE OUT command was
2233 		 * received, with the additional sense code set to
2234 		 * RESERVATIONS RELEASED.
2235 		 */
2236 		if (pr_holder &&
2237 		    (type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY ||
2238 		     type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY)) {
2239 			list_for_each_entry(pr_reg_p,
2240 					&pr_tmpl->registration_list,
2241 					pr_reg_list) {
2242 
2243 				target_ua_allocate_lun(
2244 					pr_reg_p->pr_reg_nacl,
2245 					pr_reg_p->pr_res_mapped_lun,
2246 					0x2A,
2247 					ASCQ_2AH_RESERVATIONS_RELEASED);
2248 			}
2249 		}
2250 
2251 		spin_unlock(&pr_tmpl->registration_lock);
2252 	}
2253 
2254 	ret = core_scsi3_update_and_write_aptpl(dev, aptpl);
2255 
2256 out:
2257 	if (pr_reg)
2258 		core_scsi3_put_pr_reg(pr_reg);
2259 	return ret;
2260 }
2261 
2262 unsigned char *core_scsi3_pr_dump_type(int type)
2263 {
2264 	switch (type) {
2265 	case PR_TYPE_WRITE_EXCLUSIVE:
2266 		return "Write Exclusive Access";
2267 	case PR_TYPE_EXCLUSIVE_ACCESS:
2268 		return "Exclusive Access";
2269 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2270 		return "Write Exclusive Access, Registrants Only";
2271 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2272 		return "Exclusive Access, Registrants Only";
2273 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2274 		return "Write Exclusive Access, All Registrants";
2275 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2276 		return "Exclusive Access, All Registrants";
2277 	default:
2278 		break;
2279 	}
2280 
2281 	return "Unknown SPC-3 PR Type";
2282 }
2283 
2284 static sense_reason_t
2285 core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
2286 {
2287 	struct se_device *dev = cmd->se_dev;
2288 	struct se_session *se_sess = cmd->se_sess;
2289 	struct se_lun *se_lun = cmd->se_lun;
2290 	struct t10_pr_registration *pr_reg, *pr_res_holder;
2291 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2292 	char i_buf[PR_REG_ISID_ID_LEN];
2293 	sense_reason_t ret;
2294 
2295 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2296 
2297 	if (!se_sess || !se_lun) {
2298 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2299 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2300 	}
2301 	/*
2302 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2303 	 */
2304 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2305 				se_sess);
2306 	if (!pr_reg) {
2307 		pr_err("SPC-3 PR: Unable to locate"
2308 			" PR_REGISTERED *pr_reg for RESERVE\n");
2309 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2310 	}
2311 	/*
2312 	 * From spc4r17 Section 5.7.9: Reserving:
2313 	 *
2314 	 * An application client creates a persistent reservation by issuing
2315 	 * a PERSISTENT RESERVE OUT command with RESERVE service action through
2316 	 * a registered I_T nexus with the following parameters:
2317 	 *    a) RESERVATION KEY set to the value of the reservation key that is
2318 	 * 	 registered with the logical unit for the I_T nexus; and
2319 	 */
2320 	if (res_key != pr_reg->pr_res_key) {
2321 		pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2322 			" does not match existing SA REGISTER res_key:"
2323 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2324 		ret = TCM_RESERVATION_CONFLICT;
2325 		goto out_put_pr_reg;
2326 	}
2327 	/*
2328 	 * From spc4r17 Section 5.7.9: Reserving:
2329 	 *
2330 	 * From above:
2331 	 *  b) TYPE field and SCOPE field set to the persistent reservation
2332 	 *     being created.
2333 	 *
2334 	 * Only one persistent reservation is allowed at a time per logical unit
2335 	 * and that persistent reservation has a scope of LU_SCOPE.
2336 	 */
2337 	if (scope != PR_SCOPE_LU_SCOPE) {
2338 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2339 		ret = TCM_INVALID_PARAMETER_LIST;
2340 		goto out_put_pr_reg;
2341 	}
2342 	/*
2343 	 * See if we have an existing PR reservation holder pointer at
2344 	 * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2345 	 * *pr_res_holder.
2346 	 */
2347 	spin_lock(&dev->dev_reservation_lock);
2348 	pr_res_holder = dev->dev_pr_res_holder;
2349 	if (pr_res_holder) {
2350 		/*
2351 		 * From spc4r17 Section 5.7.9: Reserving:
2352 		 *
2353 		 * If the device server receives a PERSISTENT RESERVE OUT
2354 		 * command from an I_T nexus other than a persistent reservation
2355 		 * holder (see 5.7.10) that attempts to create a persistent
2356 		 * reservation when a persistent reservation already exists for
2357 		 * the logical unit, then the command shall be completed with
2358 		 * RESERVATION CONFLICT status.
2359 		 */
2360 		if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2361 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2362 			pr_err("SPC-3 PR: Attempted RESERVE from"
2363 				" [%s]: %s while reservation already held by"
2364 				" [%s]: %s, returning RESERVATION_CONFLICT\n",
2365 				cmd->se_tfo->get_fabric_name(),
2366 				se_sess->se_node_acl->initiatorname,
2367 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2368 				pr_res_holder->pr_reg_nacl->initiatorname);
2369 
2370 			spin_unlock(&dev->dev_reservation_lock);
2371 			ret = TCM_RESERVATION_CONFLICT;
2372 			goto out_put_pr_reg;
2373 		}
2374 		/*
2375 		 * From spc4r17 Section 5.7.9: Reserving:
2376 		 *
2377 		 * If a persistent reservation holder attempts to modify the
2378 		 * type or scope of an existing persistent reservation, the
2379 		 * command shall be completed with RESERVATION CONFLICT status.
2380 		 */
2381 		if ((pr_res_holder->pr_res_type != type) ||
2382 		    (pr_res_holder->pr_res_scope != scope)) {
2383 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2384 			pr_err("SPC-3 PR: Attempted RESERVE from"
2385 				" [%s]: %s trying to change TYPE and/or SCOPE,"
2386 				" while reservation already held by [%s]: %s,"
2387 				" returning RESERVATION_CONFLICT\n",
2388 				cmd->se_tfo->get_fabric_name(),
2389 				se_sess->se_node_acl->initiatorname,
2390 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2391 				pr_res_holder->pr_reg_nacl->initiatorname);
2392 
2393 			spin_unlock(&dev->dev_reservation_lock);
2394 			ret = TCM_RESERVATION_CONFLICT;
2395 			goto out_put_pr_reg;
2396 		}
2397 		/*
2398 		 * From spc4r17 Section 5.7.9: Reserving:
2399 		 *
2400 		 * If the device server receives a PERSISTENT RESERVE OUT
2401 		 * command with RESERVE service action where the TYPE field and
2402 		 * the SCOPE field contain the same values as the existing type
2403 		 * and scope from a persistent reservation holder, it shall not
2404 		 * make any change to the existing persistent reservation and
2405 		 * shall completethe command with GOOD status.
2406 		 */
2407 		spin_unlock(&dev->dev_reservation_lock);
2408 		ret = 0;
2409 		goto out_put_pr_reg;
2410 	}
2411 	/*
2412 	 * Otherwise, our *pr_reg becomes the PR reservation holder for said
2413 	 * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2414 	 */
2415 	pr_reg->pr_res_scope = scope;
2416 	pr_reg->pr_res_type = type;
2417 	pr_reg->pr_res_holder = 1;
2418 	dev->dev_pr_res_holder = pr_reg;
2419 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2420 
2421 	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2422 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2423 		cmd->se_tfo->get_fabric_name(), core_scsi3_pr_dump_type(type),
2424 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2425 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2426 			cmd->se_tfo->get_fabric_name(),
2427 			se_sess->se_node_acl->initiatorname,
2428 			i_buf);
2429 	spin_unlock(&dev->dev_reservation_lock);
2430 
2431 	if (pr_tmpl->pr_aptpl_active)
2432 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2433 
2434 	ret = 0;
2435 out_put_pr_reg:
2436 	core_scsi3_put_pr_reg(pr_reg);
2437 	return ret;
2438 }
2439 
2440 static sense_reason_t
2441 core_scsi3_emulate_pro_reserve(struct se_cmd *cmd, int type, int scope,
2442 		u64 res_key)
2443 {
2444 	switch (type) {
2445 	case PR_TYPE_WRITE_EXCLUSIVE:
2446 	case PR_TYPE_EXCLUSIVE_ACCESS:
2447 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2448 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2449 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2450 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2451 		return core_scsi3_pro_reserve(cmd, type, scope, res_key);
2452 	default:
2453 		pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2454 			" 0x%02x\n", type);
2455 		return TCM_INVALID_CDB_FIELD;
2456 	}
2457 }
2458 
2459 /*
2460  * Called with struct se_device->dev_reservation_lock held.
2461  */
2462 static void __core_scsi3_complete_pro_release(
2463 	struct se_device *dev,
2464 	struct se_node_acl *se_nacl,
2465 	struct t10_pr_registration *pr_reg,
2466 	int explicit,
2467 	int unreg)
2468 {
2469 	const struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2470 	char i_buf[PR_REG_ISID_ID_LEN];
2471 	int pr_res_type = 0, pr_res_scope = 0;
2472 
2473 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2474 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2475 	/*
2476 	 * Go ahead and release the current PR reservation holder.
2477 	 * If an All Registrants reservation is currently active and
2478 	 * a unregister operation is requested, replace the current
2479 	 * dev_pr_res_holder with another active registration.
2480 	 */
2481 	if (dev->dev_pr_res_holder) {
2482 		pr_res_type = dev->dev_pr_res_holder->pr_res_type;
2483 		pr_res_scope = dev->dev_pr_res_holder->pr_res_scope;
2484 		dev->dev_pr_res_holder->pr_res_type = 0;
2485 		dev->dev_pr_res_holder->pr_res_scope = 0;
2486 		dev->dev_pr_res_holder->pr_res_holder = 0;
2487 		dev->dev_pr_res_holder = NULL;
2488 	}
2489 	if (!unreg)
2490 		goto out;
2491 
2492 	spin_lock(&dev->t10_pr.registration_lock);
2493 	list_del_init(&pr_reg->pr_reg_list);
2494 	/*
2495 	 * If the I_T nexus is a reservation holder, the persistent reservation
2496 	 * is of an all registrants type, and the I_T nexus is the last remaining
2497 	 * registered I_T nexus, then the device server shall also release the
2498 	 * persistent reservation.
2499 	 */
2500 	if (!list_empty(&dev->t10_pr.registration_list) &&
2501 	    ((pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2502 	     (pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))) {
2503 		dev->dev_pr_res_holder =
2504 			list_entry(dev->t10_pr.registration_list.next,
2505 				   struct t10_pr_registration, pr_reg_list);
2506 		dev->dev_pr_res_holder->pr_res_type = pr_res_type;
2507 		dev->dev_pr_res_holder->pr_res_scope = pr_res_scope;
2508 		dev->dev_pr_res_holder->pr_res_holder = 1;
2509 	}
2510 	spin_unlock(&dev->t10_pr.registration_lock);
2511 out:
2512 	if (!dev->dev_pr_res_holder) {
2513 		pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2514 			" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2515 			tfo->get_fabric_name(), (explicit) ? "explicit" :
2516 			"implicit", core_scsi3_pr_dump_type(pr_res_type),
2517 			(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2518 	}
2519 	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2520 		tfo->get_fabric_name(), se_nacl->initiatorname,
2521 		i_buf);
2522 	/*
2523 	 * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2524 	 */
2525 	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2526 }
2527 
2528 static sense_reason_t
2529 core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
2530 		u64 res_key)
2531 {
2532 	struct se_device *dev = cmd->se_dev;
2533 	struct se_session *se_sess = cmd->se_sess;
2534 	struct se_lun *se_lun = cmd->se_lun;
2535 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2536 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2537 	sense_reason_t ret = 0;
2538 
2539 	if (!se_sess || !se_lun) {
2540 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2541 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2542 	}
2543 	/*
2544 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2545 	 */
2546 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2547 	if (!pr_reg) {
2548 		pr_err("SPC-3 PR: Unable to locate"
2549 			" PR_REGISTERED *pr_reg for RELEASE\n");
2550 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2551 	}
2552 	/*
2553 	 * From spc4r17 Section 5.7.11.2 Releasing:
2554 	 *
2555 	 * If there is no persistent reservation or in response to a persistent
2556 	 * reservation release request from a registered I_T nexus that is not a
2557 	 * persistent reservation holder (see 5.7.10), the device server shall
2558 	 * do the following:
2559 	 *
2560 	 *     a) Not release the persistent reservation, if any;
2561 	 *     b) Not remove any registrations; and
2562 	 *     c) Complete the command with GOOD status.
2563 	 */
2564 	spin_lock(&dev->dev_reservation_lock);
2565 	pr_res_holder = dev->dev_pr_res_holder;
2566 	if (!pr_res_holder) {
2567 		/*
2568 		 * No persistent reservation, return GOOD status.
2569 		 */
2570 		spin_unlock(&dev->dev_reservation_lock);
2571 		goto out_put_pr_reg;
2572 	}
2573 
2574 	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2575 		/*
2576 		 * Release request from a registered I_T nexus that is not a
2577 		 * persistent reservation holder. return GOOD status.
2578 		 */
2579 		spin_unlock(&dev->dev_reservation_lock);
2580 		goto out_put_pr_reg;
2581 	}
2582 
2583 	/*
2584 	 * From spc4r17 Section 5.7.11.2 Releasing:
2585 	 *
2586 	 * Only the persistent reservation holder (see 5.7.10) is allowed to
2587 	 * release a persistent reservation.
2588 	 *
2589 	 * An application client releases the persistent reservation by issuing
2590 	 * a PERSISTENT RESERVE OUT command with RELEASE service action through
2591 	 * an I_T nexus that is a persistent reservation holder with the
2592 	 * following parameters:
2593 	 *
2594 	 *     a) RESERVATION KEY field set to the value of the reservation key
2595 	 *	  that is registered with the logical unit for the I_T nexus;
2596 	 */
2597 	if (res_key != pr_reg->pr_res_key) {
2598 		pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2599 			" does not match existing SA REGISTER res_key:"
2600 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2601 		spin_unlock(&dev->dev_reservation_lock);
2602 		ret = TCM_RESERVATION_CONFLICT;
2603 		goto out_put_pr_reg;
2604 	}
2605 	/*
2606 	 * From spc4r17 Section 5.7.11.2 Releasing and above:
2607 	 *
2608 	 * b) TYPE field and SCOPE field set to match the persistent
2609 	 *    reservation being released.
2610 	 */
2611 	if ((pr_res_holder->pr_res_type != type) ||
2612 	    (pr_res_holder->pr_res_scope != scope)) {
2613 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2614 		pr_err("SPC-3 PR RELEASE: Attempted to release"
2615 			" reservation from [%s]: %s with different TYPE "
2616 			"and/or SCOPE  while reservation already held by"
2617 			" [%s]: %s, returning RESERVATION_CONFLICT\n",
2618 			cmd->se_tfo->get_fabric_name(),
2619 			se_sess->se_node_acl->initiatorname,
2620 			pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2621 			pr_res_holder->pr_reg_nacl->initiatorname);
2622 
2623 		spin_unlock(&dev->dev_reservation_lock);
2624 		ret = TCM_RESERVATION_CONFLICT;
2625 		goto out_put_pr_reg;
2626 	}
2627 	/*
2628 	 * In response to a persistent reservation release request from the
2629 	 * persistent reservation holder the device server shall perform a
2630 	 * release by doing the following as an uninterrupted series of actions:
2631 	 * a) Release the persistent reservation;
2632 	 * b) Not remove any registration(s);
2633 	 * c) If the released persistent reservation is a registrants only type
2634 	 * or all registrants type persistent reservation,
2635 	 *    the device server shall establish a unit attention condition for
2636 	 *    the initiator port associated with every regis-
2637 	 *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2638 	 *    RESERVE OUT command with RELEASE service action was received,
2639 	 *    with the additional sense code set to RESERVATIONS RELEASED; and
2640 	 * d) If the persistent reservation is of any other type, the device
2641 	 *    server shall not establish a unit attention condition.
2642 	 */
2643 	__core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2644 					  pr_reg, 1, 0);
2645 
2646 	spin_unlock(&dev->dev_reservation_lock);
2647 
2648 	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2649 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2650 	    (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2651 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2652 		/*
2653 		 * If no UNIT ATTENTION conditions will be established for
2654 		 * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2655 		 * go ahead and check for APTPL=1 update+write below
2656 		 */
2657 		goto write_aptpl;
2658 	}
2659 
2660 	spin_lock(&pr_tmpl->registration_lock);
2661 	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2662 			pr_reg_list) {
2663 		/*
2664 		 * Do not establish a UNIT ATTENTION condition
2665 		 * for the calling I_T Nexus
2666 		 */
2667 		if (pr_reg_p == pr_reg)
2668 			continue;
2669 
2670 		target_ua_allocate_lun(pr_reg_p->pr_reg_nacl,
2671 				pr_reg_p->pr_res_mapped_lun,
2672 				0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2673 	}
2674 	spin_unlock(&pr_tmpl->registration_lock);
2675 
2676 write_aptpl:
2677 	if (pr_tmpl->pr_aptpl_active)
2678 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2679 
2680 out_put_pr_reg:
2681 	core_scsi3_put_pr_reg(pr_reg);
2682 	return ret;
2683 }
2684 
2685 static sense_reason_t
2686 core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
2687 {
2688 	struct se_device *dev = cmd->se_dev;
2689 	struct se_node_acl *pr_reg_nacl;
2690 	struct se_session *se_sess = cmd->se_sess;
2691 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2692 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2693 	u64 pr_res_mapped_lun = 0;
2694 	int calling_it_nexus = 0;
2695 	/*
2696 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2697 	 */
2698 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2699 			se_sess->se_node_acl, se_sess);
2700 	if (!pr_reg_n) {
2701 		pr_err("SPC-3 PR: Unable to locate"
2702 			" PR_REGISTERED *pr_reg for CLEAR\n");
2703 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2704 	}
2705 	/*
2706 	 * From spc4r17 section 5.7.11.6, Clearing:
2707 	 *
2708 	 * Any application client may release the persistent reservation and
2709 	 * remove all registrations from a device server by issuing a
2710 	 * PERSISTENT RESERVE OUT command with CLEAR service action through a
2711 	 * registered I_T nexus with the following parameter:
2712 	 *
2713 	 *	a) RESERVATION KEY field set to the value of the reservation key
2714 	 * 	   that is registered with the logical unit for the I_T nexus.
2715 	 */
2716 	if (res_key != pr_reg_n->pr_res_key) {
2717 		pr_err("SPC-3 PR REGISTER: Received"
2718 			" res_key: 0x%016Lx does not match"
2719 			" existing SA REGISTER res_key:"
2720 			" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2721 		core_scsi3_put_pr_reg(pr_reg_n);
2722 		return TCM_RESERVATION_CONFLICT;
2723 	}
2724 	/*
2725 	 * a) Release the persistent reservation, if any;
2726 	 */
2727 	spin_lock(&dev->dev_reservation_lock);
2728 	pr_res_holder = dev->dev_pr_res_holder;
2729 	if (pr_res_holder) {
2730 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2731 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
2732 						  pr_res_holder, 0, 0);
2733 	}
2734 	spin_unlock(&dev->dev_reservation_lock);
2735 	/*
2736 	 * b) Remove all registration(s) (see spc4r17 5.7.7);
2737 	 */
2738 	spin_lock(&pr_tmpl->registration_lock);
2739 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2740 			&pr_tmpl->registration_list, pr_reg_list) {
2741 
2742 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2743 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2744 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2745 		__core_scsi3_free_registration(dev, pr_reg, NULL,
2746 					calling_it_nexus);
2747 		/*
2748 		 * e) Establish a unit attention condition for the initiator
2749 		 *    port associated with every registered I_T nexus other
2750 		 *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2751 		 *    command with CLEAR service action was received, with the
2752 		 *    additional sense code set to RESERVATIONS PREEMPTED.
2753 		 */
2754 		if (!calling_it_nexus)
2755 			target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun,
2756 				0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2757 	}
2758 	spin_unlock(&pr_tmpl->registration_lock);
2759 
2760 	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2761 		cmd->se_tfo->get_fabric_name());
2762 
2763 	core_scsi3_update_and_write_aptpl(cmd->se_dev, false);
2764 
2765 	core_scsi3_pr_generation(dev);
2766 	return 0;
2767 }
2768 
2769 /*
2770  * Called with struct se_device->dev_reservation_lock held.
2771  */
2772 static void __core_scsi3_complete_pro_preempt(
2773 	struct se_device *dev,
2774 	struct t10_pr_registration *pr_reg,
2775 	struct list_head *preempt_and_abort_list,
2776 	int type,
2777 	int scope,
2778 	enum preempt_type preempt_type)
2779 {
2780 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2781 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2782 	char i_buf[PR_REG_ISID_ID_LEN];
2783 
2784 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2785 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2786 	/*
2787 	 * Do an implicit RELEASE of the existing reservation.
2788 	 */
2789 	if (dev->dev_pr_res_holder)
2790 		__core_scsi3_complete_pro_release(dev, nacl,
2791 						  dev->dev_pr_res_holder, 0, 0);
2792 
2793 	dev->dev_pr_res_holder = pr_reg;
2794 	pr_reg->pr_res_holder = 1;
2795 	pr_reg->pr_res_type = type;
2796 	pr_reg->pr_res_scope = scope;
2797 
2798 	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2799 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2800 		tfo->get_fabric_name(), (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2801 		core_scsi3_pr_dump_type(type),
2802 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2803 	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2804 		tfo->get_fabric_name(), (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2805 		nacl->initiatorname, i_buf);
2806 	/*
2807 	 * For PREEMPT_AND_ABORT, add the preempting reservation's
2808 	 * struct t10_pr_registration to the list that will be compared
2809 	 * against received CDBs..
2810 	 */
2811 	if (preempt_and_abort_list)
2812 		list_add_tail(&pr_reg->pr_reg_abort_list,
2813 				preempt_and_abort_list);
2814 }
2815 
2816 static void core_scsi3_release_preempt_and_abort(
2817 	struct list_head *preempt_and_abort_list,
2818 	struct t10_pr_registration *pr_reg_holder)
2819 {
2820 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2821 
2822 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2823 				pr_reg_abort_list) {
2824 
2825 		list_del(&pr_reg->pr_reg_abort_list);
2826 		if (pr_reg_holder == pr_reg)
2827 			continue;
2828 		if (pr_reg->pr_res_holder) {
2829 			pr_warn("pr_reg->pr_res_holder still set\n");
2830 			continue;
2831 		}
2832 
2833 		pr_reg->pr_reg_deve = NULL;
2834 		pr_reg->pr_reg_nacl = NULL;
2835 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
2836 	}
2837 }
2838 
2839 static sense_reason_t
2840 core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
2841 		u64 sa_res_key, enum preempt_type preempt_type)
2842 {
2843 	struct se_device *dev = cmd->se_dev;
2844 	struct se_node_acl *pr_reg_nacl;
2845 	struct se_session *se_sess = cmd->se_sess;
2846 	LIST_HEAD(preempt_and_abort_list);
2847 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2848 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2849 	u64 pr_res_mapped_lun = 0;
2850 	int all_reg = 0, calling_it_nexus = 0;
2851 	bool sa_res_key_unmatched = sa_res_key != 0;
2852 	int prh_type = 0, prh_scope = 0;
2853 
2854 	if (!se_sess)
2855 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2856 
2857 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2858 				se_sess);
2859 	if (!pr_reg_n) {
2860 		pr_err("SPC-3 PR: Unable to locate"
2861 			" PR_REGISTERED *pr_reg for PREEMPT%s\n",
2862 			(preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "");
2863 		return TCM_RESERVATION_CONFLICT;
2864 	}
2865 	if (pr_reg_n->pr_res_key != res_key) {
2866 		core_scsi3_put_pr_reg(pr_reg_n);
2867 		return TCM_RESERVATION_CONFLICT;
2868 	}
2869 	if (scope != PR_SCOPE_LU_SCOPE) {
2870 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2871 		core_scsi3_put_pr_reg(pr_reg_n);
2872 		return TCM_INVALID_PARAMETER_LIST;
2873 	}
2874 
2875 	spin_lock(&dev->dev_reservation_lock);
2876 	pr_res_holder = dev->dev_pr_res_holder;
2877 	if (pr_res_holder &&
2878 	   ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2879 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
2880 		all_reg = 1;
2881 
2882 	if (!all_reg && !sa_res_key) {
2883 		spin_unlock(&dev->dev_reservation_lock);
2884 		core_scsi3_put_pr_reg(pr_reg_n);
2885 		return TCM_INVALID_PARAMETER_LIST;
2886 	}
2887 	/*
2888 	 * From spc4r17, section 5.7.11.4.4 Removing Registrations:
2889 	 *
2890 	 * If the SERVICE ACTION RESERVATION KEY field does not identify a
2891 	 * persistent reservation holder or there is no persistent reservation
2892 	 * holder (i.e., there is no persistent reservation), then the device
2893 	 * server shall perform a preempt by doing the following in an
2894 	 * uninterrupted series of actions. (See below..)
2895 	 */
2896 	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
2897 		/*
2898 		 * No existing or SA Reservation Key matching reservations..
2899 		 *
2900 		 * PROUT SA PREEMPT with All Registrant type reservations are
2901 		 * allowed to be processed without a matching SA Reservation Key
2902 		 */
2903 		spin_lock(&pr_tmpl->registration_lock);
2904 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2905 				&pr_tmpl->registration_list, pr_reg_list) {
2906 			/*
2907 			 * Removing of registrations in non all registrants
2908 			 * type reservations without a matching SA reservation
2909 			 * key.
2910 			 *
2911 			 * a) Remove the registrations for all I_T nexuses
2912 			 *    specified by the SERVICE ACTION RESERVATION KEY
2913 			 *    field;
2914 			 * b) Ignore the contents of the SCOPE and TYPE fields;
2915 			 * c) Process tasks as defined in 5.7.1; and
2916 			 * d) Establish a unit attention condition for the
2917 			 *    initiator port associated with every I_T nexus
2918 			 *    that lost its registration other than the I_T
2919 			 *    nexus on which the PERSISTENT RESERVE OUT command
2920 			 *    was received, with the additional sense code set
2921 			 *    to REGISTRATIONS PREEMPTED.
2922 			 */
2923 			if (!all_reg) {
2924 				if (pr_reg->pr_res_key != sa_res_key)
2925 					continue;
2926 				sa_res_key_unmatched = false;
2927 
2928 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2929 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2930 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2931 				__core_scsi3_free_registration(dev, pr_reg,
2932 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2933 						NULL, calling_it_nexus);
2934 			} else {
2935 				/*
2936 				 * Case for any existing all registrants type
2937 				 * reservation, follow logic in spc4r17 section
2938 				 * 5.7.11.4 Preempting, Table 52 and Figure 7.
2939 				 *
2940 				 * For a ZERO SA Reservation key, release
2941 				 * all other registrations and do an implicit
2942 				 * release of active persistent reservation.
2943 				 *
2944 				 * For a non-ZERO SA Reservation key, only
2945 				 * release the matching reservation key from
2946 				 * registrations.
2947 				 */
2948 				if ((sa_res_key) &&
2949 				     (pr_reg->pr_res_key != sa_res_key))
2950 					continue;
2951 				sa_res_key_unmatched = false;
2952 
2953 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2954 				if (calling_it_nexus)
2955 					continue;
2956 
2957 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2958 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2959 				__core_scsi3_free_registration(dev, pr_reg,
2960 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2961 						NULL, 0);
2962 			}
2963 			if (!calling_it_nexus)
2964 				target_ua_allocate_lun(pr_reg_nacl,
2965 					pr_res_mapped_lun, 0x2A,
2966 					ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2967 		}
2968 		spin_unlock(&pr_tmpl->registration_lock);
2969 		/*
2970 		 * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
2971 		 * a PREEMPT AND ABORT service action sets the SERVICE ACTION
2972 		 * RESERVATION KEY field to a value that does not match any
2973 		 * registered reservation key, then the device server shall
2974 		 * complete the command with RESERVATION CONFLICT status.
2975 		 */
2976 		if (sa_res_key_unmatched) {
2977 			spin_unlock(&dev->dev_reservation_lock);
2978 			core_scsi3_put_pr_reg(pr_reg_n);
2979 			return TCM_RESERVATION_CONFLICT;
2980 		}
2981 		/*
2982 		 * For an existing all registrants type reservation
2983 		 * with a zero SA rservation key, preempt the existing
2984 		 * reservation with the new PR type and scope.
2985 		 */
2986 		if (pr_res_holder && all_reg && !(sa_res_key)) {
2987 			__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
2988 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2989 				type, scope, preempt_type);
2990 
2991 			if (preempt_type == PREEMPT_AND_ABORT)
2992 				core_scsi3_release_preempt_and_abort(
2993 					&preempt_and_abort_list, pr_reg_n);
2994 		}
2995 		spin_unlock(&dev->dev_reservation_lock);
2996 
2997 		if (pr_tmpl->pr_aptpl_active)
2998 			core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2999 
3000 		core_scsi3_put_pr_reg(pr_reg_n);
3001 		core_scsi3_pr_generation(cmd->se_dev);
3002 		return 0;
3003 	}
3004 	/*
3005 	 * The PREEMPTing SA reservation key matches that of the
3006 	 * existing persistent reservation, first, we check if
3007 	 * we are preempting our own reservation.
3008 	 * From spc4r17, section 5.7.11.4.3 Preempting
3009 	 * persistent reservations and registration handling
3010 	 *
3011 	 * If an all registrants persistent reservation is not
3012 	 * present, it is not an error for the persistent
3013 	 * reservation holder to preempt itself (i.e., a
3014 	 * PERSISTENT RESERVE OUT with a PREEMPT service action
3015 	 * or a PREEMPT AND ABORT service action with the
3016 	 * SERVICE ACTION RESERVATION KEY value equal to the
3017 	 * persistent reservation holder's reservation key that
3018 	 * is received from the persistent reservation holder).
3019 	 * In that case, the device server shall establish the
3020 	 * new persistent reservation and maintain the
3021 	 * registration.
3022 	 */
3023 	prh_type = pr_res_holder->pr_res_type;
3024 	prh_scope = pr_res_holder->pr_res_scope;
3025 	/*
3026 	 * If the SERVICE ACTION RESERVATION KEY field identifies a
3027 	 * persistent reservation holder (see 5.7.10), the device
3028 	 * server shall perform a preempt by doing the following as
3029 	 * an uninterrupted series of actions:
3030 	 *
3031 	 * a) Release the persistent reservation for the holder
3032 	 *    identified by the SERVICE ACTION RESERVATION KEY field;
3033 	 */
3034 	if (pr_reg_n != pr_res_holder)
3035 		__core_scsi3_complete_pro_release(dev,
3036 						  pr_res_holder->pr_reg_nacl,
3037 						  dev->dev_pr_res_holder, 0, 0);
3038 	/*
3039 	 * b) Remove the registrations for all I_T nexuses identified
3040 	 *    by the SERVICE ACTION RESERVATION KEY field, except the
3041 	 *    I_T nexus that is being used for the PERSISTENT RESERVE
3042 	 *    OUT command. If an all registrants persistent reservation
3043 	 *    is present and the SERVICE ACTION RESERVATION KEY field
3044 	 *    is set to zero, then all registrations shall be removed
3045 	 *    except for that of the I_T nexus that is being used for
3046 	 *    the PERSISTENT RESERVE OUT command;
3047 	 */
3048 	spin_lock(&pr_tmpl->registration_lock);
3049 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3050 			&pr_tmpl->registration_list, pr_reg_list) {
3051 
3052 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3053 		if (calling_it_nexus)
3054 			continue;
3055 
3056 		if (pr_reg->pr_res_key != sa_res_key)
3057 			continue;
3058 
3059 		pr_reg_nacl = pr_reg->pr_reg_nacl;
3060 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3061 		__core_scsi3_free_registration(dev, pr_reg,
3062 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3063 				calling_it_nexus);
3064 		/*
3065 		 * e) Establish a unit attention condition for the initiator
3066 		 *    port associated with every I_T nexus that lost its
3067 		 *    persistent reservation and/or registration, with the
3068 		 *    additional sense code set to REGISTRATIONS PREEMPTED;
3069 		 */
3070 		target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3071 				ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3072 	}
3073 	spin_unlock(&pr_tmpl->registration_lock);
3074 	/*
3075 	 * c) Establish a persistent reservation for the preempting
3076 	 *    I_T nexus using the contents of the SCOPE and TYPE fields;
3077 	 */
3078 	__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3079 			(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3080 			type, scope, preempt_type);
3081 	/*
3082 	 * d) Process tasks as defined in 5.7.1;
3083 	 * e) See above..
3084 	 * f) If the type or scope has changed, then for every I_T nexus
3085 	 *    whose reservation key was not removed, except for the I_T
3086 	 *    nexus on which the PERSISTENT RESERVE OUT command was
3087 	 *    received, the device server shall establish a unit
3088 	 *    attention condition for the initiator port associated with
3089 	 *    that I_T nexus, with the additional sense code set to
3090 	 *    RESERVATIONS RELEASED. If the type or scope have not
3091 	 *    changed, then no unit attention condition(s) shall be
3092 	 *    established for this reason.
3093 	 */
3094 	if ((prh_type != type) || (prh_scope != scope)) {
3095 		spin_lock(&pr_tmpl->registration_lock);
3096 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3097 				&pr_tmpl->registration_list, pr_reg_list) {
3098 
3099 			calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3100 			if (calling_it_nexus)
3101 				continue;
3102 
3103 			target_ua_allocate_lun(pr_reg->pr_reg_nacl,
3104 					pr_reg->pr_res_mapped_lun, 0x2A,
3105 					ASCQ_2AH_RESERVATIONS_RELEASED);
3106 		}
3107 		spin_unlock(&pr_tmpl->registration_lock);
3108 	}
3109 	spin_unlock(&dev->dev_reservation_lock);
3110 	/*
3111 	 * Call LUN_RESET logic upon list of struct t10_pr_registration,
3112 	 * All received CDBs for the matching existing reservation and
3113 	 * registrations undergo ABORT_TASK logic.
3114 	 *
3115 	 * From there, core_scsi3_release_preempt_and_abort() will
3116 	 * release every registration in the list (which have already
3117 	 * been removed from the primary pr_reg list), except the
3118 	 * new persistent reservation holder, the calling Initiator Port.
3119 	 */
3120 	if (preempt_type == PREEMPT_AND_ABORT) {
3121 		core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3122 		core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3123 						pr_reg_n);
3124 	}
3125 
3126 	if (pr_tmpl->pr_aptpl_active)
3127 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
3128 
3129 	core_scsi3_put_pr_reg(pr_reg_n);
3130 	core_scsi3_pr_generation(cmd->se_dev);
3131 	return 0;
3132 }
3133 
3134 static sense_reason_t
3135 core_scsi3_emulate_pro_preempt(struct se_cmd *cmd, int type, int scope,
3136 		u64 res_key, u64 sa_res_key, enum preempt_type preempt_type)
3137 {
3138 	switch (type) {
3139 	case PR_TYPE_WRITE_EXCLUSIVE:
3140 	case PR_TYPE_EXCLUSIVE_ACCESS:
3141 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3142 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3143 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3144 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3145 		return core_scsi3_pro_preempt(cmd, type, scope, res_key,
3146 					      sa_res_key, preempt_type);
3147 	default:
3148 		pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3149 			" Type: 0x%02x\n", (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "", type);
3150 		return TCM_INVALID_CDB_FIELD;
3151 	}
3152 }
3153 
3154 
3155 static sense_reason_t
3156 core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
3157 		u64 sa_res_key, int aptpl, int unreg)
3158 {
3159 	struct se_session *se_sess = cmd->se_sess;
3160 	struct se_device *dev = cmd->se_dev;
3161 	struct se_dev_entry *dest_se_deve = NULL;
3162 	struct se_lun *se_lun = cmd->se_lun, *tmp_lun;
3163 	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3164 	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3165 	const struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3166 	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3167 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3168 	unsigned char *buf;
3169 	const unsigned char *initiator_str;
3170 	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
3171 	u32 tid_len, tmp_tid_len;
3172 	int new_reg = 0, type, scope, matching_iname;
3173 	sense_reason_t ret;
3174 	unsigned short rtpi;
3175 	unsigned char proto_ident;
3176 
3177 	if (!se_sess || !se_lun) {
3178 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3179 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3180 	}
3181 
3182 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3183 	se_tpg = se_sess->se_tpg;
3184 	tf_ops = se_tpg->se_tpg_tfo;
3185 	/*
3186 	 * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3187 	 *	Register behaviors for a REGISTER AND MOVE service action
3188 	 *
3189 	 * Locate the existing *pr_reg via struct se_node_acl pointers
3190 	 */
3191 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3192 				se_sess);
3193 	if (!pr_reg) {
3194 		pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3195 			" *pr_reg for REGISTER_AND_MOVE\n");
3196 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3197 	}
3198 	/*
3199 	 * The provided reservation key much match the existing reservation key
3200 	 * provided during this initiator's I_T nexus registration.
3201 	 */
3202 	if (res_key != pr_reg->pr_res_key) {
3203 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3204 			" res_key: 0x%016Lx does not match existing SA REGISTER"
3205 			" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3206 		ret = TCM_RESERVATION_CONFLICT;
3207 		goto out_put_pr_reg;
3208 	}
3209 	/*
3210 	 * The service active reservation key needs to be non zero
3211 	 */
3212 	if (!sa_res_key) {
3213 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3214 			" sa_res_key\n");
3215 		ret = TCM_INVALID_PARAMETER_LIST;
3216 		goto out_put_pr_reg;
3217 	}
3218 
3219 	/*
3220 	 * Determine the Relative Target Port Identifier where the reservation
3221 	 * will be moved to for the TransportID containing SCSI initiator WWN
3222 	 * information.
3223 	 */
3224 	buf = transport_kmap_data_sg(cmd);
3225 	if (!buf) {
3226 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3227 		goto out_put_pr_reg;
3228 	}
3229 
3230 	rtpi = (buf[18] & 0xff) << 8;
3231 	rtpi |= buf[19] & 0xff;
3232 	tid_len = (buf[20] & 0xff) << 24;
3233 	tid_len |= (buf[21] & 0xff) << 16;
3234 	tid_len |= (buf[22] & 0xff) << 8;
3235 	tid_len |= buf[23] & 0xff;
3236 	transport_kunmap_data_sg(cmd);
3237 	buf = NULL;
3238 
3239 	if ((tid_len + 24) != cmd->data_length) {
3240 		pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3241 			" does not equal CDB data_length: %u\n", tid_len,
3242 			cmd->data_length);
3243 		ret = TCM_INVALID_PARAMETER_LIST;
3244 		goto out_put_pr_reg;
3245 	}
3246 
3247 	spin_lock(&dev->se_port_lock);
3248 	list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
3249 		if (tmp_lun->lun_rtpi != rtpi)
3250 			continue;
3251 		dest_se_tpg = tmp_lun->lun_tpg;
3252 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3253 		if (!dest_tf_ops)
3254 			continue;
3255 
3256 		atomic_inc_mb(&dest_se_tpg->tpg_pr_ref_count);
3257 		spin_unlock(&dev->se_port_lock);
3258 
3259 		if (core_scsi3_tpg_depend_item(dest_se_tpg)) {
3260 			pr_err("core_scsi3_tpg_depend_item() failed"
3261 				" for dest_se_tpg\n");
3262 			atomic_dec_mb(&dest_se_tpg->tpg_pr_ref_count);
3263 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3264 			goto out_put_pr_reg;
3265 		}
3266 
3267 		spin_lock(&dev->se_port_lock);
3268 		break;
3269 	}
3270 	spin_unlock(&dev->se_port_lock);
3271 
3272 	if (!dest_se_tpg || !dest_tf_ops) {
3273 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3274 			" fabric ops from Relative Target Port Identifier:"
3275 			" %hu\n", rtpi);
3276 		ret = TCM_INVALID_PARAMETER_LIST;
3277 		goto out_put_pr_reg;
3278 	}
3279 
3280 	buf = transport_kmap_data_sg(cmd);
3281 	if (!buf) {
3282 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3283 		goto out_put_pr_reg;
3284 	}
3285 	proto_ident = (buf[24] & 0x0f);
3286 
3287 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3288 			" 0x%02x\n", proto_ident);
3289 
3290 	if (proto_ident != dest_se_tpg->proto_id) {
3291 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3292 			" proto_ident: 0x%02x does not match ident: 0x%02x"
3293 			" from fabric: %s\n", proto_ident,
3294 			dest_se_tpg->proto_id,
3295 			dest_tf_ops->get_fabric_name());
3296 		ret = TCM_INVALID_PARAMETER_LIST;
3297 		goto out;
3298 	}
3299 	initiator_str = target_parse_pr_out_transport_id(dest_se_tpg,
3300 			(const char *)&buf[24], &tmp_tid_len, &iport_ptr);
3301 	if (!initiator_str) {
3302 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3303 			" initiator_str from Transport ID\n");
3304 		ret = TCM_INVALID_PARAMETER_LIST;
3305 		goto out;
3306 	}
3307 
3308 	transport_kunmap_data_sg(cmd);
3309 	buf = NULL;
3310 
3311 	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3312 		" %s\n", dest_tf_ops->get_fabric_name(), (iport_ptr != NULL) ?
3313 		"port" : "device", initiator_str, (iport_ptr != NULL) ?
3314 		iport_ptr : "");
3315 	/*
3316 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3317 	 * action specifies a TransportID that is the same as the initiator port
3318 	 * of the I_T nexus for the command received, then the command shall
3319 	 * be terminated with CHECK CONDITION status, with the sense key set to
3320 	 * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3321 	 * IN PARAMETER LIST.
3322 	 */
3323 	pr_reg_nacl = pr_reg->pr_reg_nacl;
3324 	matching_iname = (!strcmp(initiator_str,
3325 				  pr_reg_nacl->initiatorname)) ? 1 : 0;
3326 	if (!matching_iname)
3327 		goto after_iport_check;
3328 
3329 	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3330 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3331 			" matches: %s on received I_T Nexus\n", initiator_str,
3332 			pr_reg_nacl->initiatorname);
3333 		ret = TCM_INVALID_PARAMETER_LIST;
3334 		goto out;
3335 	}
3336 	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3337 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3338 			" matches: %s %s on received I_T Nexus\n",
3339 			initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3340 			pr_reg->pr_reg_isid);
3341 		ret = TCM_INVALID_PARAMETER_LIST;
3342 		goto out;
3343 	}
3344 after_iport_check:
3345 	/*
3346 	 * Locate the destination struct se_node_acl from the received Transport ID
3347 	 */
3348 	mutex_lock(&dest_se_tpg->acl_node_mutex);
3349 	dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3350 				initiator_str);
3351 	if (dest_node_acl)
3352 		atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
3353 	mutex_unlock(&dest_se_tpg->acl_node_mutex);
3354 
3355 	if (!dest_node_acl) {
3356 		pr_err("Unable to locate %s dest_node_acl for"
3357 			" TransportID%s\n", dest_tf_ops->get_fabric_name(),
3358 			initiator_str);
3359 		ret = TCM_INVALID_PARAMETER_LIST;
3360 		goto out;
3361 	}
3362 
3363 	if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
3364 		pr_err("core_scsi3_nodeacl_depend_item() for"
3365 			" dest_node_acl\n");
3366 		atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
3367 		dest_node_acl = NULL;
3368 		ret = TCM_INVALID_PARAMETER_LIST;
3369 		goto out;
3370 	}
3371 
3372 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3373 		" %s from TransportID\n", dest_tf_ops->get_fabric_name(),
3374 		dest_node_acl->initiatorname);
3375 
3376 	/*
3377 	 * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3378 	 * PORT IDENTIFIER.
3379 	 */
3380 	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3381 	if (!dest_se_deve) {
3382 		pr_err("Unable to locate %s dest_se_deve from RTPI:"
3383 			" %hu\n",  dest_tf_ops->get_fabric_name(), rtpi);
3384 		ret = TCM_INVALID_PARAMETER_LIST;
3385 		goto out;
3386 	}
3387 
3388 	if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
3389 		pr_err("core_scsi3_lunacl_depend_item() failed\n");
3390 		kref_put(&dest_se_deve->pr_kref, target_pr_kref_release);
3391 		dest_se_deve = NULL;
3392 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3393 		goto out;
3394 	}
3395 
3396 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3397 		" ACL for dest_se_deve->mapped_lun: %llu\n",
3398 		dest_tf_ops->get_fabric_name(), dest_node_acl->initiatorname,
3399 		dest_se_deve->mapped_lun);
3400 
3401 	/*
3402 	 * A persistent reservation needs to already existing in order to
3403 	 * successfully complete the REGISTER_AND_MOVE service action..
3404 	 */
3405 	spin_lock(&dev->dev_reservation_lock);
3406 	pr_res_holder = dev->dev_pr_res_holder;
3407 	if (!pr_res_holder) {
3408 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3409 			" currently held\n");
3410 		spin_unlock(&dev->dev_reservation_lock);
3411 		ret = TCM_INVALID_CDB_FIELD;
3412 		goto out;
3413 	}
3414 	/*
3415 	 * The received on I_T Nexus must be the reservation holder.
3416 	 *
3417 	 * From spc4r17 section 5.7.8  Table 50 --
3418 	 * 	Register behaviors for a REGISTER AND MOVE service action
3419 	 */
3420 	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
3421 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3422 			" Nexus is not reservation holder\n");
3423 		spin_unlock(&dev->dev_reservation_lock);
3424 		ret = TCM_RESERVATION_CONFLICT;
3425 		goto out;
3426 	}
3427 	/*
3428 	 * From spc4r17 section 5.7.8: registering and moving reservation
3429 	 *
3430 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3431 	 * action is received and the established persistent reservation is a
3432 	 * Write Exclusive - All Registrants type or Exclusive Access -
3433 	 * All Registrants type reservation, then the command shall be completed
3434 	 * with RESERVATION CONFLICT status.
3435 	 */
3436 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3437 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3438 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3439 			" reservation for type: %s\n",
3440 			core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3441 		spin_unlock(&dev->dev_reservation_lock);
3442 		ret = TCM_RESERVATION_CONFLICT;
3443 		goto out;
3444 	}
3445 	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3446 	/*
3447 	 * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3448 	 */
3449 	type = pr_res_holder->pr_res_type;
3450 	scope = pr_res_holder->pr_res_type;
3451 	/*
3452 	 * c) Associate the reservation key specified in the SERVICE ACTION
3453 	 *    RESERVATION KEY field with the I_T nexus specified as the
3454 	 *    destination of the register and move, where:
3455 	 *    A) The I_T nexus is specified by the TransportID and the
3456 	 *	 RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3457 	 *    B) Regardless of the TransportID format used, the association for
3458 	 *       the initiator port is based on either the initiator port name
3459 	 *       (see 3.1.71) on SCSI transport protocols where port names are
3460 	 *       required or the initiator port identifier (see 3.1.70) on SCSI
3461 	 *       transport protocols where port names are not required;
3462 	 * d) Register the reservation key specified in the SERVICE ACTION
3463 	 *    RESERVATION KEY field;
3464 	 * e) Retain the reservation key specified in the SERVICE ACTION
3465 	 *    RESERVATION KEY field and associated information;
3466 	 *
3467 	 * Also, It is not an error for a REGISTER AND MOVE service action to
3468 	 * register an I_T nexus that is already registered with the same
3469 	 * reservation key or a different reservation key.
3470 	 */
3471 	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3472 					iport_ptr);
3473 	if (!dest_pr_reg) {
3474 		struct se_lun *dest_lun = rcu_dereference_check(dest_se_deve->se_lun,
3475 				atomic_read(&dest_se_deve->pr_kref.refcount) != 0);
3476 
3477 		spin_unlock(&dev->dev_reservation_lock);
3478 		if (core_scsi3_alloc_registration(cmd->se_dev, dest_node_acl,
3479 					dest_lun, dest_se_deve, dest_se_deve->mapped_lun,
3480 					iport_ptr, sa_res_key, 0, aptpl, 2, 1)) {
3481 			ret = TCM_INVALID_PARAMETER_LIST;
3482 			goto out;
3483 		}
3484 		spin_lock(&dev->dev_reservation_lock);
3485 		dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3486 						iport_ptr);
3487 		new_reg = 1;
3488 	}
3489 	/*
3490 	 * f) Release the persistent reservation for the persistent reservation
3491 	 *    holder (i.e., the I_T nexus on which the
3492 	 */
3493 	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
3494 					  dev->dev_pr_res_holder, 0, 0);
3495 	/*
3496 	 * g) Move the persistent reservation to the specified I_T nexus using
3497 	 *    the same scope and type as the persistent reservation released in
3498 	 *    item f); and
3499 	 */
3500 	dev->dev_pr_res_holder = dest_pr_reg;
3501 	dest_pr_reg->pr_res_holder = 1;
3502 	dest_pr_reg->pr_res_type = type;
3503 	pr_reg->pr_res_scope = scope;
3504 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
3505 	/*
3506 	 * Increment PRGeneration for existing registrations..
3507 	 */
3508 	if (!new_reg)
3509 		dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3510 	spin_unlock(&dev->dev_reservation_lock);
3511 
3512 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3513 		" created new reservation holder TYPE: %s on object RTPI:"
3514 		" %hu  PRGeneration: 0x%08x\n", dest_tf_ops->get_fabric_name(),
3515 		core_scsi3_pr_dump_type(type), rtpi,
3516 		dest_pr_reg->pr_res_generation);
3517 	pr_debug("SPC-3 PR Successfully moved reservation from"
3518 		" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3519 		tf_ops->get_fabric_name(), pr_reg_nacl->initiatorname,
3520 		i_buf, dest_tf_ops->get_fabric_name(),
3521 		dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3522 		iport_ptr : "");
3523 	/*
3524 	 * It is now safe to release configfs group dependencies for destination
3525 	 * of Transport ID Initiator Device/Port Identifier
3526 	 */
3527 	core_scsi3_lunacl_undepend_item(dest_se_deve);
3528 	core_scsi3_nodeacl_undepend_item(dest_node_acl);
3529 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3530 	/*
3531 	 * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3532 	 * nexus on which PERSISTENT RESERVE OUT command was received.
3533 	 */
3534 	if (unreg) {
3535 		spin_lock(&pr_tmpl->registration_lock);
3536 		__core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3537 		spin_unlock(&pr_tmpl->registration_lock);
3538 	} else
3539 		core_scsi3_put_pr_reg(pr_reg);
3540 
3541 	core_scsi3_update_and_write_aptpl(cmd->se_dev, aptpl);
3542 
3543 	transport_kunmap_data_sg(cmd);
3544 
3545 	core_scsi3_put_pr_reg(dest_pr_reg);
3546 	return 0;
3547 out:
3548 	if (buf)
3549 		transport_kunmap_data_sg(cmd);
3550 	if (dest_se_deve)
3551 		core_scsi3_lunacl_undepend_item(dest_se_deve);
3552 	if (dest_node_acl)
3553 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
3554 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3555 
3556 out_put_pr_reg:
3557 	core_scsi3_put_pr_reg(pr_reg);
3558 	return ret;
3559 }
3560 
3561 static unsigned long long core_scsi3_extract_reservation_key(unsigned char *cdb)
3562 {
3563 	unsigned int __v1, __v2;
3564 
3565 	__v1 = (cdb[0] << 24) | (cdb[1] << 16) | (cdb[2] << 8) | cdb[3];
3566 	__v2 = (cdb[4] << 24) | (cdb[5] << 16) | (cdb[6] << 8) | cdb[7];
3567 
3568 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
3569 }
3570 
3571 /*
3572  * See spc4r17 section 6.14 Table 170
3573  */
3574 sense_reason_t
3575 target_scsi3_emulate_pr_out(struct se_cmd *cmd)
3576 {
3577 	struct se_device *dev = cmd->se_dev;
3578 	unsigned char *cdb = &cmd->t_task_cdb[0];
3579 	unsigned char *buf;
3580 	u64 res_key, sa_res_key;
3581 	int sa, scope, type, aptpl;
3582 	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3583 	sense_reason_t ret;
3584 
3585 	/*
3586 	 * Following spc2r20 5.5.1 Reservations overview:
3587 	 *
3588 	 * If a logical unit has been reserved by any RESERVE command and is
3589 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3590 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
3591 	 * initiator or service action and shall terminate with a RESERVATION
3592 	 * CONFLICT status.
3593 	 */
3594 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
3595 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3596 			" SPC-2 reservation is held, returning"
3597 			" RESERVATION_CONFLICT\n");
3598 		return TCM_RESERVATION_CONFLICT;
3599 	}
3600 
3601 	/*
3602 	 * FIXME: A NULL struct se_session pointer means an this is not coming from
3603 	 * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3604 	 */
3605 	if (!cmd->se_sess)
3606 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3607 
3608 	if (cmd->data_length < 24) {
3609 		pr_warn("SPC-PR: Received PR OUT parameter list"
3610 			" length too small: %u\n", cmd->data_length);
3611 		return TCM_INVALID_PARAMETER_LIST;
3612 	}
3613 
3614 	/*
3615 	 * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3616 	 */
3617 	sa = (cdb[1] & 0x1f);
3618 	scope = (cdb[2] & 0xf0);
3619 	type = (cdb[2] & 0x0f);
3620 
3621 	buf = transport_kmap_data_sg(cmd);
3622 	if (!buf)
3623 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3624 
3625 	/*
3626 	 * From PERSISTENT_RESERVE_OUT parameter list (payload)
3627 	 */
3628 	res_key = core_scsi3_extract_reservation_key(&buf[0]);
3629 	sa_res_key = core_scsi3_extract_reservation_key(&buf[8]);
3630 	/*
3631 	 * REGISTER_AND_MOVE uses a different SA parameter list containing
3632 	 * SCSI TransportIDs.
3633 	 */
3634 	if (sa != PRO_REGISTER_AND_MOVE) {
3635 		spec_i_pt = (buf[20] & 0x08);
3636 		all_tg_pt = (buf[20] & 0x04);
3637 		aptpl = (buf[20] & 0x01);
3638 	} else {
3639 		aptpl = (buf[17] & 0x01);
3640 		unreg = (buf[17] & 0x02);
3641 	}
3642 	/*
3643 	 * If the backend device has been configured to force APTPL metadata
3644 	 * write-out, go ahead and propigate aptpl=1 down now.
3645 	 */
3646 	if (dev->dev_attrib.force_pr_aptpl)
3647 		aptpl = 1;
3648 
3649 	transport_kunmap_data_sg(cmd);
3650 	buf = NULL;
3651 
3652 	/*
3653 	 * SPEC_I_PT=1 is only valid for Service action: REGISTER
3654 	 */
3655 	if (spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER))
3656 		return TCM_INVALID_PARAMETER_LIST;
3657 
3658 	/*
3659 	 * From spc4r17 section 6.14:
3660 	 *
3661 	 * If the SPEC_I_PT bit is set to zero, the service action is not
3662 	 * REGISTER AND MOVE, and the parameter list length is not 24, then
3663 	 * the command shall be terminated with CHECK CONDITION status, with
3664 	 * the sense key set to ILLEGAL REQUEST, and the additional sense
3665 	 * code set to PARAMETER LIST LENGTH ERROR.
3666 	 */
3667 	if (!spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER_AND_MOVE) &&
3668 	    (cmd->data_length != 24)) {
3669 		pr_warn("SPC-PR: Received PR OUT illegal parameter"
3670 			" list length: %u\n", cmd->data_length);
3671 		return TCM_INVALID_PARAMETER_LIST;
3672 	}
3673 
3674 	/*
3675 	 * (core_scsi3_emulate_pro_* function parameters
3676 	 * are defined by spc4r17 Table 174:
3677 	 * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3678 	 */
3679 	switch (sa) {
3680 	case PRO_REGISTER:
3681 		ret = core_scsi3_emulate_pro_register(cmd,
3682 			res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER);
3683 		break;
3684 	case PRO_RESERVE:
3685 		ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3686 		break;
3687 	case PRO_RELEASE:
3688 		ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3689 		break;
3690 	case PRO_CLEAR:
3691 		ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3692 		break;
3693 	case PRO_PREEMPT:
3694 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3695 					res_key, sa_res_key, PREEMPT);
3696 		break;
3697 	case PRO_PREEMPT_AND_ABORT:
3698 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3699 					res_key, sa_res_key, PREEMPT_AND_ABORT);
3700 		break;
3701 	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3702 		ret = core_scsi3_emulate_pro_register(cmd,
3703 			0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER_AND_IGNORE_EXISTING_KEY);
3704 		break;
3705 	case PRO_REGISTER_AND_MOVE:
3706 		ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3707 				sa_res_key, aptpl, unreg);
3708 		break;
3709 	default:
3710 		pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3711 			" action: 0x%02x\n", cdb[1] & 0x1f);
3712 		return TCM_INVALID_CDB_FIELD;
3713 	}
3714 
3715 	if (!ret)
3716 		target_complete_cmd(cmd, GOOD);
3717 	return ret;
3718 }
3719 
3720 /*
3721  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3722  *
3723  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3724  */
3725 static sense_reason_t
3726 core_scsi3_pri_read_keys(struct se_cmd *cmd)
3727 {
3728 	struct se_device *dev = cmd->se_dev;
3729 	struct t10_pr_registration *pr_reg;
3730 	unsigned char *buf;
3731 	u32 add_len = 0, off = 8;
3732 
3733 	if (cmd->data_length < 8) {
3734 		pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3735 			" too small\n", cmd->data_length);
3736 		return TCM_INVALID_CDB_FIELD;
3737 	}
3738 
3739 	buf = transport_kmap_data_sg(cmd);
3740 	if (!buf)
3741 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3742 
3743 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3744 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3745 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3746 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3747 
3748 	spin_lock(&dev->t10_pr.registration_lock);
3749 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
3750 			pr_reg_list) {
3751 		/*
3752 		 * Check for overflow of 8byte PRI READ_KEYS payload and
3753 		 * next reservation key list descriptor.
3754 		 */
3755 		if ((add_len + 8) > (cmd->data_length - 8))
3756 			break;
3757 
3758 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3759 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3760 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3761 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3762 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3763 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3764 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3765 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3766 
3767 		add_len += 8;
3768 	}
3769 	spin_unlock(&dev->t10_pr.registration_lock);
3770 
3771 	buf[4] = ((add_len >> 24) & 0xff);
3772 	buf[5] = ((add_len >> 16) & 0xff);
3773 	buf[6] = ((add_len >> 8) & 0xff);
3774 	buf[7] = (add_len & 0xff);
3775 
3776 	transport_kunmap_data_sg(cmd);
3777 
3778 	return 0;
3779 }
3780 
3781 /*
3782  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3783  *
3784  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3785  */
3786 static sense_reason_t
3787 core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3788 {
3789 	struct se_device *dev = cmd->se_dev;
3790 	struct t10_pr_registration *pr_reg;
3791 	unsigned char *buf;
3792 	u64 pr_res_key;
3793 	u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
3794 
3795 	if (cmd->data_length < 8) {
3796 		pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3797 			" too small\n", cmd->data_length);
3798 		return TCM_INVALID_CDB_FIELD;
3799 	}
3800 
3801 	buf = transport_kmap_data_sg(cmd);
3802 	if (!buf)
3803 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3804 
3805 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3806 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3807 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3808 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3809 
3810 	spin_lock(&dev->dev_reservation_lock);
3811 	pr_reg = dev->dev_pr_res_holder;
3812 	if (pr_reg) {
3813 		/*
3814 		 * Set the hardcoded Additional Length
3815 		 */
3816 		buf[4] = ((add_len >> 24) & 0xff);
3817 		buf[5] = ((add_len >> 16) & 0xff);
3818 		buf[6] = ((add_len >> 8) & 0xff);
3819 		buf[7] = (add_len & 0xff);
3820 
3821 		if (cmd->data_length < 22)
3822 			goto err;
3823 
3824 		/*
3825 		 * Set the Reservation key.
3826 		 *
3827 		 * From spc4r17, section 5.7.10:
3828 		 * A persistent reservation holder has its reservation key
3829 		 * returned in the parameter data from a PERSISTENT
3830 		 * RESERVE IN command with READ RESERVATION service action as
3831 		 * follows:
3832 		 * a) For a persistent reservation of the type Write Exclusive
3833 		 *    - All Registrants or Exclusive Access ­ All Regitrants,
3834 		 *      the reservation key shall be set to zero; or
3835 		 * b) For all other persistent reservation types, the
3836 		 *    reservation key shall be set to the registered
3837 		 *    reservation key for the I_T nexus that holds the
3838 		 *    persistent reservation.
3839 		 */
3840 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3841 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3842 			pr_res_key = 0;
3843 		else
3844 			pr_res_key = pr_reg->pr_res_key;
3845 
3846 		buf[8] = ((pr_res_key >> 56) & 0xff);
3847 		buf[9] = ((pr_res_key >> 48) & 0xff);
3848 		buf[10] = ((pr_res_key >> 40) & 0xff);
3849 		buf[11] = ((pr_res_key >> 32) & 0xff);
3850 		buf[12] = ((pr_res_key >> 24) & 0xff);
3851 		buf[13] = ((pr_res_key >> 16) & 0xff);
3852 		buf[14] = ((pr_res_key >> 8) & 0xff);
3853 		buf[15] = (pr_res_key & 0xff);
3854 		/*
3855 		 * Set the SCOPE and TYPE
3856 		 */
3857 		buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3858 			  (pr_reg->pr_res_type & 0x0f);
3859 	}
3860 
3861 err:
3862 	spin_unlock(&dev->dev_reservation_lock);
3863 	transport_kunmap_data_sg(cmd);
3864 
3865 	return 0;
3866 }
3867 
3868 /*
3869  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3870  *
3871  * See spc4r17 section 6.13.4 Table 165
3872  */
3873 static sense_reason_t
3874 core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3875 {
3876 	struct se_device *dev = cmd->se_dev;
3877 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3878 	unsigned char *buf;
3879 	u16 add_len = 8; /* Hardcoded to 8. */
3880 
3881 	if (cmd->data_length < 6) {
3882 		pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
3883 			" %u too small\n", cmd->data_length);
3884 		return TCM_INVALID_CDB_FIELD;
3885 	}
3886 
3887 	buf = transport_kmap_data_sg(cmd);
3888 	if (!buf)
3889 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3890 
3891 	buf[0] = ((add_len >> 8) & 0xff);
3892 	buf[1] = (add_len & 0xff);
3893 	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
3894 	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
3895 	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
3896 	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
3897 	/*
3898 	 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
3899 	 * set the TMV: Task Mask Valid bit.
3900 	 */
3901 	buf[3] |= 0x80;
3902 	/*
3903 	 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
3904 	 */
3905 	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
3906 	/*
3907 	 * PTPL_A: Persistence across Target Power Loss Active bit
3908 	 */
3909 	if (pr_tmpl->pr_aptpl_active)
3910 		buf[3] |= 0x01;
3911 	/*
3912 	 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
3913 	 */
3914 	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3915 	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
3916 	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
3917 	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
3918 	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
3919 	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3920 
3921 	transport_kunmap_data_sg(cmd);
3922 
3923 	return 0;
3924 }
3925 
3926 /*
3927  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
3928  *
3929  * See spc4r17 section 6.13.5 Table 168 and 169
3930  */
3931 static sense_reason_t
3932 core_scsi3_pri_read_full_status(struct se_cmd *cmd)
3933 {
3934 	struct se_device *dev = cmd->se_dev;
3935 	struct se_node_acl *se_nacl;
3936 	struct se_portal_group *se_tpg;
3937 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
3938 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3939 	unsigned char *buf;
3940 	u32 add_desc_len = 0, add_len = 0;
3941 	u32 off = 8; /* off into first Full Status descriptor */
3942 	int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
3943 	int exp_desc_len, desc_len;
3944 	bool all_reg = false;
3945 
3946 	if (cmd->data_length < 8) {
3947 		pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
3948 			" too small\n", cmd->data_length);
3949 		return TCM_INVALID_CDB_FIELD;
3950 	}
3951 
3952 	buf = transport_kmap_data_sg(cmd);
3953 	if (!buf)
3954 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3955 
3956 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3957 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3958 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3959 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3960 
3961 	spin_lock(&dev->dev_reservation_lock);
3962 	if (dev->dev_pr_res_holder) {
3963 		struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
3964 
3965 		if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
3966 		    pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
3967 			all_reg = true;
3968 			pr_res_type = pr_holder->pr_res_type;
3969 			pr_res_scope = pr_holder->pr_res_scope;
3970 		}
3971 	}
3972 	spin_unlock(&dev->dev_reservation_lock);
3973 
3974 	spin_lock(&pr_tmpl->registration_lock);
3975 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3976 			&pr_tmpl->registration_list, pr_reg_list) {
3977 
3978 		se_nacl = pr_reg->pr_reg_nacl;
3979 		se_tpg = pr_reg->pr_reg_nacl->se_tpg;
3980 		add_desc_len = 0;
3981 
3982 		atomic_inc_mb(&pr_reg->pr_res_holders);
3983 		spin_unlock(&pr_tmpl->registration_lock);
3984 		/*
3985 		 * Determine expected length of $FABRIC_MOD specific
3986 		 * TransportID full status descriptor..
3987 		 */
3988 		exp_desc_len = target_get_pr_transport_id_len(se_nacl, pr_reg,
3989 					&format_code);
3990 		if (exp_desc_len < 0 ||
3991 		    exp_desc_len + add_len > cmd->data_length) {
3992 			pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
3993 				" out of buffer: %d\n", cmd->data_length);
3994 			spin_lock(&pr_tmpl->registration_lock);
3995 			atomic_dec_mb(&pr_reg->pr_res_holders);
3996 			break;
3997 		}
3998 		/*
3999 		 * Set RESERVATION KEY
4000 		 */
4001 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
4002 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
4003 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
4004 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
4005 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
4006 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
4007 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
4008 		buf[off++] = (pr_reg->pr_res_key & 0xff);
4009 		off += 4; /* Skip Over Reserved area */
4010 
4011 		/*
4012 		 * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
4013 		 */
4014 		if (pr_reg->pr_reg_all_tg_pt)
4015 			buf[off] = 0x02;
4016 		/*
4017 		 * The struct se_lun pointer will be present for the
4018 		 * reservation holder for PR_HOLDER bit.
4019 		 *
4020 		 * Also, if this registration is the reservation
4021 		 * holder or there is an All Registrants reservation
4022 		 * active, fill in SCOPE and TYPE in the next byte.
4023 		 */
4024 		if (pr_reg->pr_res_holder) {
4025 			buf[off++] |= 0x01;
4026 			buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
4027 				     (pr_reg->pr_res_type & 0x0f);
4028 		} else if (all_reg) {
4029 			buf[off++] |= 0x01;
4030 			buf[off++] = (pr_res_scope & 0xf0) |
4031 				     (pr_res_type & 0x0f);
4032 		} else {
4033 			off += 2;
4034 		}
4035 
4036 		off += 4; /* Skip over reserved area */
4037 		/*
4038 		 * From spc4r17 6.3.15:
4039 		 *
4040 		 * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
4041 		 * IDENTIFIER field contains the relative port identifier (see
4042 		 * 3.1.120) of the target port that is part of the I_T nexus
4043 		 * described by this full status descriptor. If the ALL_TG_PT
4044 		 * bit is set to one, the contents of the RELATIVE TARGET PORT
4045 		 * IDENTIFIER field are not defined by this standard.
4046 		 */
4047 		if (!pr_reg->pr_reg_all_tg_pt) {
4048 			u16 sep_rtpi = pr_reg->tg_pt_sep_rtpi;
4049 
4050 			buf[off++] = ((sep_rtpi >> 8) & 0xff);
4051 			buf[off++] = (sep_rtpi & 0xff);
4052 		} else
4053 			off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */
4054 
4055 		buf[off+4] = se_tpg->proto_id;
4056 
4057 		/*
4058 		 * Now, have the $FABRIC_MOD fill in the transport ID.
4059 		 */
4060 		desc_len = target_get_pr_transport_id(se_nacl, pr_reg,
4061 				&format_code, &buf[off+4]);
4062 
4063 		spin_lock(&pr_tmpl->registration_lock);
4064 		atomic_dec_mb(&pr_reg->pr_res_holders);
4065 
4066 		if (desc_len < 0)
4067 			break;
4068 		/*
4069 		 * Set the ADDITIONAL DESCRIPTOR LENGTH
4070 		 */
4071 		buf[off++] = ((desc_len >> 24) & 0xff);
4072 		buf[off++] = ((desc_len >> 16) & 0xff);
4073 		buf[off++] = ((desc_len >> 8) & 0xff);
4074 		buf[off++] = (desc_len & 0xff);
4075 		/*
4076 		 * Size of full desctipor header minus TransportID
4077 		 * containing $FABRIC_MOD specific) initiator device/port
4078 		 * WWN information.
4079 		 *
4080 		 *  See spc4r17 Section 6.13.5 Table 169
4081 		 */
4082 		add_desc_len = (24 + desc_len);
4083 
4084 		off += desc_len;
4085 		add_len += add_desc_len;
4086 	}
4087 	spin_unlock(&pr_tmpl->registration_lock);
4088 	/*
4089 	 * Set ADDITIONAL_LENGTH
4090 	 */
4091 	buf[4] = ((add_len >> 24) & 0xff);
4092 	buf[5] = ((add_len >> 16) & 0xff);
4093 	buf[6] = ((add_len >> 8) & 0xff);
4094 	buf[7] = (add_len & 0xff);
4095 
4096 	transport_kunmap_data_sg(cmd);
4097 
4098 	return 0;
4099 }
4100 
4101 sense_reason_t
4102 target_scsi3_emulate_pr_in(struct se_cmd *cmd)
4103 {
4104 	sense_reason_t ret;
4105 
4106 	/*
4107 	 * Following spc2r20 5.5.1 Reservations overview:
4108 	 *
4109 	 * If a logical unit has been reserved by any RESERVE command and is
4110 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4111 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
4112 	 * initiator or service action and shall terminate with a RESERVATION
4113 	 * CONFLICT status.
4114 	 */
4115 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
4116 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4117 			" SPC-2 reservation is held, returning"
4118 			" RESERVATION_CONFLICT\n");
4119 		return TCM_RESERVATION_CONFLICT;
4120 	}
4121 
4122 	switch (cmd->t_task_cdb[1] & 0x1f) {
4123 	case PRI_READ_KEYS:
4124 		ret = core_scsi3_pri_read_keys(cmd);
4125 		break;
4126 	case PRI_READ_RESERVATION:
4127 		ret = core_scsi3_pri_read_reservation(cmd);
4128 		break;
4129 	case PRI_REPORT_CAPABILITIES:
4130 		ret = core_scsi3_pri_report_capabilities(cmd);
4131 		break;
4132 	case PRI_READ_FULL_STATUS:
4133 		ret = core_scsi3_pri_read_full_status(cmd);
4134 		break;
4135 	default:
4136 		pr_err("Unknown PERSISTENT_RESERVE_IN service"
4137 			" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4138 		return TCM_INVALID_CDB_FIELD;
4139 	}
4140 
4141 	if (!ret)
4142 		target_complete_cmd(cmd, GOOD);
4143 	return ret;
4144 }
4145 
4146 sense_reason_t
4147 target_check_reservation(struct se_cmd *cmd)
4148 {
4149 	struct se_device *dev = cmd->se_dev;
4150 	sense_reason_t ret;
4151 
4152 	if (!cmd->se_sess)
4153 		return 0;
4154 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
4155 		return 0;
4156 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
4157 		return 0;
4158 
4159 	spin_lock(&dev->dev_reservation_lock);
4160 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
4161 		ret = target_scsi2_reservation_check(cmd);
4162 	else
4163 		ret = target_scsi3_pr_reservation_check(cmd);
4164 	spin_unlock(&dev->dev_reservation_lock);
4165 
4166 	return ret;
4167 }
4168