1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * Filename:  target_core_pr.c
4  *
5  * This file contains SPC-3 compliant persistent reservations and
6  * legacy SPC-2 reservations with compatible reservation handling (CRH=1)
7  *
8  * (c) Copyright 2009-2013 Datera, Inc.
9  *
10  * Nicholas A. Bellinger <nab@kernel.org>
11  *
12  ******************************************************************************/
13 
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 #include <linux/list.h>
17 #include <linux/vmalloc.h>
18 #include <linux/file.h>
19 #include <linux/fcntl.h>
20 #include <linux/fs.h>
21 #include <scsi/scsi_proto.h>
22 #include <asm/unaligned.h>
23 
24 #include <target/target_core_base.h>
25 #include <target/target_core_backend.h>
26 #include <target/target_core_fabric.h>
27 
28 #include "target_core_internal.h"
29 #include "target_core_pr.h"
30 #include "target_core_ua.h"
31 
32 /*
33  * Used for Specify Initiator Ports Capable Bit (SPEC_I_PT)
34  */
35 struct pr_transport_id_holder {
36 	struct t10_pr_registration *dest_pr_reg;
37 	struct se_portal_group *dest_tpg;
38 	struct se_node_acl *dest_node_acl;
39 	struct se_dev_entry *dest_se_deve;
40 	struct list_head dest_list;
41 };
42 
43 void core_pr_dump_initiator_port(
44 	struct t10_pr_registration *pr_reg,
45 	char *buf,
46 	u32 size)
47 {
48 	if (!pr_reg->isid_present_at_reg) {
49 		buf[0] = '\0';
50 		return;
51 	}
52 
53 	snprintf(buf, size, ",i,0x%s", pr_reg->pr_reg_isid);
54 }
55 
56 enum register_type {
57 	REGISTER,
58 	REGISTER_AND_IGNORE_EXISTING_KEY,
59 	REGISTER_AND_MOVE,
60 };
61 
62 enum preempt_type {
63 	PREEMPT,
64 	PREEMPT_AND_ABORT,
65 };
66 
67 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
68 					      struct t10_pr_registration *, int, int);
69 
70 static int is_reservation_holder(
71 	struct t10_pr_registration *pr_res_holder,
72 	struct t10_pr_registration *pr_reg)
73 {
74 	int pr_res_type;
75 
76 	if (pr_res_holder) {
77 		pr_res_type = pr_res_holder->pr_res_type;
78 
79 		return pr_res_holder == pr_reg ||
80 		       pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
81 		       pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG;
82 	}
83 	return 0;
84 }
85 
86 static sense_reason_t
87 target_scsi2_reservation_check(struct se_cmd *cmd)
88 {
89 	struct se_device *dev = cmd->se_dev;
90 	struct se_session *sess = cmd->se_sess;
91 
92 	switch (cmd->t_task_cdb[0]) {
93 	case INQUIRY:
94 	case RELEASE:
95 	case RELEASE_10:
96 		return 0;
97 	default:
98 		break;
99 	}
100 
101 	if (!dev->reservation_holder || !sess)
102 		return 0;
103 
104 	if (dev->reservation_holder->se_node_acl != sess->se_node_acl)
105 		return TCM_RESERVATION_CONFLICT;
106 
107 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
108 		if (dev->dev_res_bin_isid != sess->sess_bin_isid)
109 			return TCM_RESERVATION_CONFLICT;
110 	}
111 
112 	return 0;
113 }
114 
115 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
116 					struct se_node_acl *, struct se_session *);
117 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
118 
119 static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
120 {
121 	struct se_session *se_sess = cmd->se_sess;
122 	struct se_device *dev = cmd->se_dev;
123 	struct t10_pr_registration *pr_reg;
124 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
125 	int conflict = 0;
126 
127 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
128 			se_sess);
129 	if (pr_reg) {
130 		/*
131 		 * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
132 		 * behavior
133 		 *
134 		 * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
135 		 * status, but no reservation shall be established and the
136 		 * persistent reservation shall not be changed, if the command
137 		 * is received from a) and b) below.
138 		 *
139 		 * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
140 		 * status, but the persistent reservation shall not be released,
141 		 * if the command is received from a) and b)
142 		 *
143 		 * a) An I_T nexus that is a persistent reservation holder; or
144 		 * b) An I_T nexus that is registered if a registrants only or
145 		 *    all registrants type persistent reservation is present.
146 		 *
147 		 * In all other cases, a RESERVE(6) command, RESERVE(10) command,
148 		 * RELEASE(6) command, or RELEASE(10) command shall be processed
149 		 * as defined in SPC-2.
150 		 */
151 		if (pr_reg->pr_res_holder) {
152 			core_scsi3_put_pr_reg(pr_reg);
153 			return 1;
154 		}
155 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
156 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
157 		    (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
158 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
159 			core_scsi3_put_pr_reg(pr_reg);
160 			return 1;
161 		}
162 		core_scsi3_put_pr_reg(pr_reg);
163 		conflict = 1;
164 	} else {
165 		/*
166 		 * Following spc2r20 5.5.1 Reservations overview:
167 		 *
168 		 * If a logical unit has executed a PERSISTENT RESERVE OUT
169 		 * command with the REGISTER or the REGISTER AND IGNORE
170 		 * EXISTING KEY service action and is still registered by any
171 		 * initiator, all RESERVE commands and all RELEASE commands
172 		 * regardless of initiator shall conflict and shall terminate
173 		 * with a RESERVATION CONFLICT status.
174 		 */
175 		spin_lock(&pr_tmpl->registration_lock);
176 		conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
177 		spin_unlock(&pr_tmpl->registration_lock);
178 	}
179 
180 	if (conflict) {
181 		pr_err("Received legacy SPC-2 RESERVE/RELEASE"
182 			" while active SPC-3 registrations exist,"
183 			" returning RESERVATION_CONFLICT\n");
184 		return -EBUSY;
185 	}
186 
187 	return 0;
188 }
189 
190 void target_release_reservation(struct se_device *dev)
191 {
192 	dev->reservation_holder = NULL;
193 	dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
194 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
195 		dev->dev_res_bin_isid = 0;
196 		dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS_WITH_ISID;
197 	}
198 }
199 
200 sense_reason_t
201 target_scsi2_reservation_release(struct se_cmd *cmd)
202 {
203 	struct se_device *dev = cmd->se_dev;
204 	struct se_session *sess = cmd->se_sess;
205 	struct se_portal_group *tpg;
206 	int rc;
207 
208 	if (!sess || !sess->se_tpg)
209 		goto out;
210 	rc = target_check_scsi2_reservation_conflict(cmd);
211 	if (rc == 1)
212 		goto out;
213 	if (rc < 0)
214 		return TCM_RESERVATION_CONFLICT;
215 
216 	spin_lock(&dev->dev_reservation_lock);
217 	if (!dev->reservation_holder || !sess)
218 		goto out_unlock;
219 
220 	if (dev->reservation_holder->se_node_acl != sess->se_node_acl)
221 		goto out_unlock;
222 
223 	if (dev->dev_res_bin_isid != sess->sess_bin_isid)
224 		goto out_unlock;
225 
226 	target_release_reservation(dev);
227 	tpg = sess->se_tpg;
228 	pr_debug("SCSI-2 Released reservation for %s LUN: %llu ->"
229 		" MAPPED LUN: %llu for %s\n",
230 		tpg->se_tpg_tfo->fabric_name,
231 		cmd->se_lun->unpacked_lun, cmd->orig_fe_lun,
232 		sess->se_node_acl->initiatorname);
233 
234 out_unlock:
235 	spin_unlock(&dev->dev_reservation_lock);
236 out:
237 	target_complete_cmd(cmd, SAM_STAT_GOOD);
238 	return 0;
239 }
240 
241 sense_reason_t
242 target_scsi2_reservation_reserve(struct se_cmd *cmd)
243 {
244 	struct se_device *dev = cmd->se_dev;
245 	struct se_session *sess = cmd->se_sess;
246 	struct se_portal_group *tpg;
247 	sense_reason_t ret = 0;
248 	int rc;
249 
250 	if ((cmd->t_task_cdb[1] & 0x01) &&
251 	    (cmd->t_task_cdb[1] & 0x02)) {
252 		pr_err("LongIO and Obsolete Bits set, returning ILLEGAL_REQUEST\n");
253 		return TCM_UNSUPPORTED_SCSI_OPCODE;
254 	}
255 	/*
256 	 * This is currently the case for target_core_mod passthrough struct se_cmd
257 	 * ops
258 	 */
259 	if (!sess || !sess->se_tpg)
260 		goto out;
261 	rc = target_check_scsi2_reservation_conflict(cmd);
262 	if (rc == 1)
263 		goto out;
264 
265 	if (rc < 0)
266 		return TCM_RESERVATION_CONFLICT;
267 
268 	tpg = sess->se_tpg;
269 	spin_lock(&dev->dev_reservation_lock);
270 	if (dev->reservation_holder &&
271 	    dev->reservation_holder->se_node_acl != sess->se_node_acl) {
272 		pr_err("SCSI-2 RESERVATION CONFLICT for %s fabric\n",
273 			tpg->se_tpg_tfo->fabric_name);
274 		pr_err("Original reserver LUN: %llu %s\n",
275 			cmd->se_lun->unpacked_lun,
276 			dev->reservation_holder->se_node_acl->initiatorname);
277 		pr_err("Current attempt - LUN: %llu -> MAPPED LUN: %llu"
278 			" from %s \n", cmd->se_lun->unpacked_lun,
279 			cmd->orig_fe_lun,
280 			sess->se_node_acl->initiatorname);
281 		ret = TCM_RESERVATION_CONFLICT;
282 		goto out_unlock;
283 	}
284 
285 	dev->reservation_holder = sess;
286 	dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS;
287 	if (sess->sess_bin_isid != 0) {
288 		dev->dev_res_bin_isid = sess->sess_bin_isid;
289 		dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS_WITH_ISID;
290 	}
291 	pr_debug("SCSI-2 Reserved %s LUN: %llu -> MAPPED LUN: %llu"
292 		" for %s\n", tpg->se_tpg_tfo->fabric_name,
293 		cmd->se_lun->unpacked_lun, cmd->orig_fe_lun,
294 		sess->se_node_acl->initiatorname);
295 
296 out_unlock:
297 	spin_unlock(&dev->dev_reservation_lock);
298 out:
299 	if (!ret)
300 		target_complete_cmd(cmd, SAM_STAT_GOOD);
301 	return ret;
302 }
303 
304 
305 /*
306  * Begin SPC-3/SPC-4 Persistent Reservations emulation support
307  *
308  * This function is called by those initiator ports who are *NOT*
309  * the active PR reservation holder when a reservation is present.
310  */
311 static int core_scsi3_pr_seq_non_holder(struct se_cmd *cmd, u32 pr_reg_type,
312 					bool isid_mismatch)
313 {
314 	unsigned char *cdb = cmd->t_task_cdb;
315 	struct se_session *se_sess = cmd->se_sess;
316 	struct se_node_acl *nacl = se_sess->se_node_acl;
317 	int other_cdb = 0;
318 	int registered_nexus = 0, ret = 1; /* Conflict by default */
319 	int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
320 	int we = 0; /* Write Exclusive */
321 	int legacy = 0; /* Act like a legacy device and return
322 			 * RESERVATION CONFLICT on some CDBs */
323 
324 	if (isid_mismatch) {
325 		registered_nexus = 0;
326 	} else {
327 		struct se_dev_entry *se_deve;
328 
329 		rcu_read_lock();
330 		se_deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
331 		if (se_deve)
332 			registered_nexus = test_bit(DEF_PR_REG_ACTIVE,
333 						    &se_deve->deve_flags);
334 		rcu_read_unlock();
335 	}
336 
337 	switch (pr_reg_type) {
338 	case PR_TYPE_WRITE_EXCLUSIVE:
339 		we = 1;
340 		fallthrough;
341 	case PR_TYPE_EXCLUSIVE_ACCESS:
342 		/*
343 		 * Some commands are only allowed for the persistent reservation
344 		 * holder.
345 		 */
346 		break;
347 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
348 		we = 1;
349 		fallthrough;
350 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
351 		/*
352 		 * Some commands are only allowed for registered I_T Nexuses.
353 		 */
354 		reg_only = 1;
355 		break;
356 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
357 		we = 1;
358 		fallthrough;
359 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
360 		/*
361 		 * Each registered I_T Nexus is a reservation holder.
362 		 */
363 		all_reg = 1;
364 		break;
365 	default:
366 		return -EINVAL;
367 	}
368 	/*
369 	 * Referenced from spc4r17 table 45 for *NON* PR holder access
370 	 */
371 	switch (cdb[0]) {
372 	case SECURITY_PROTOCOL_IN:
373 		if (registered_nexus)
374 			return 0;
375 		ret = (we) ? 0 : 1;
376 		break;
377 	case MODE_SENSE:
378 	case MODE_SENSE_10:
379 	case READ_ATTRIBUTE:
380 	case READ_BUFFER:
381 	case RECEIVE_DIAGNOSTIC:
382 		if (legacy) {
383 			ret = 1;
384 			break;
385 		}
386 		if (registered_nexus) {
387 			ret = 0;
388 			break;
389 		}
390 		ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
391 		break;
392 	case PERSISTENT_RESERVE_OUT:
393 		/*
394 		 * This follows PERSISTENT_RESERVE_OUT service actions that
395 		 * are allowed in the presence of various reservations.
396 		 * See spc4r17, table 46
397 		 */
398 		switch (cdb[1] & 0x1f) {
399 		case PRO_CLEAR:
400 		case PRO_PREEMPT:
401 		case PRO_PREEMPT_AND_ABORT:
402 			ret = (registered_nexus) ? 0 : 1;
403 			break;
404 		case PRO_REGISTER:
405 		case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
406 			ret = 0;
407 			break;
408 		case PRO_REGISTER_AND_MOVE:
409 		case PRO_RESERVE:
410 			ret = 1;
411 			break;
412 		case PRO_RELEASE:
413 			ret = (registered_nexus) ? 0 : 1;
414 			break;
415 		default:
416 			pr_err("Unknown PERSISTENT_RESERVE_OUT service"
417 				" action: 0x%02x\n", cdb[1] & 0x1f);
418 			return -EINVAL;
419 		}
420 		break;
421 	case RELEASE:
422 	case RELEASE_10:
423 		/* Handled by CRH=1 in target_scsi2_reservation_release() */
424 		ret = 0;
425 		break;
426 	case RESERVE:
427 	case RESERVE_10:
428 		/* Handled by CRH=1 in target_scsi2_reservation_reserve() */
429 		ret = 0;
430 		break;
431 	case TEST_UNIT_READY:
432 		ret = (legacy) ? 1 : 0; /* Conflict for legacy */
433 		break;
434 	case MAINTENANCE_IN:
435 		switch (cdb[1] & 0x1f) {
436 		case MI_MANAGEMENT_PROTOCOL_IN:
437 			if (registered_nexus) {
438 				ret = 0;
439 				break;
440 			}
441 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
442 			break;
443 		case MI_REPORT_SUPPORTED_OPERATION_CODES:
444 		case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
445 			if (legacy) {
446 				ret = 1;
447 				break;
448 			}
449 			if (registered_nexus) {
450 				ret = 0;
451 				break;
452 			}
453 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
454 			break;
455 		case MI_REPORT_ALIASES:
456 		case MI_REPORT_IDENTIFYING_INFORMATION:
457 		case MI_REPORT_PRIORITY:
458 		case MI_REPORT_TARGET_PGS:
459 		case MI_REPORT_TIMESTAMP:
460 			ret = 0; /* Allowed */
461 			break;
462 		default:
463 			pr_err("Unknown MI Service Action: 0x%02x\n",
464 				(cdb[1] & 0x1f));
465 			return -EINVAL;
466 		}
467 		break;
468 	case ACCESS_CONTROL_IN:
469 	case ACCESS_CONTROL_OUT:
470 	case INQUIRY:
471 	case LOG_SENSE:
472 	case SERVICE_ACTION_IN_12:
473 	case REPORT_LUNS:
474 	case REQUEST_SENSE:
475 	case PERSISTENT_RESERVE_IN:
476 		ret = 0; /*/ Allowed CDBs */
477 		break;
478 	default:
479 		other_cdb = 1;
480 		break;
481 	}
482 	/*
483 	 * Case where the CDB is explicitly allowed in the above switch
484 	 * statement.
485 	 */
486 	if (!ret && !other_cdb) {
487 		pr_debug("Allowing explicit CDB: 0x%02x for %s"
488 			" reservation holder\n", cdb[0],
489 			core_scsi3_pr_dump_type(pr_reg_type));
490 
491 		return ret;
492 	}
493 	/*
494 	 * Check if write exclusive initiator ports *NOT* holding the
495 	 * WRITE_EXCLUSIVE_* reservation.
496 	 */
497 	if (we && !registered_nexus) {
498 		if (cmd->data_direction == DMA_TO_DEVICE) {
499 			/*
500 			 * Conflict for write exclusive
501 			 */
502 			pr_debug("%s Conflict for unregistered nexus"
503 				" %s CDB: 0x%02x to %s reservation\n",
504 				transport_dump_cmd_direction(cmd),
505 				se_sess->se_node_acl->initiatorname, cdb[0],
506 				core_scsi3_pr_dump_type(pr_reg_type));
507 			return 1;
508 		} else {
509 			/*
510 			 * Allow non WRITE CDBs for all Write Exclusive
511 			 * PR TYPEs to pass for registered and
512 			 * non-registered_nexuxes NOT holding the reservation.
513 			 *
514 			 * We only make noise for the unregisterd nexuses,
515 			 * as we expect registered non-reservation holding
516 			 * nexuses to issue CDBs.
517 			 */
518 
519 			if (!registered_nexus) {
520 				pr_debug("Allowing implicit CDB: 0x%02x"
521 					" for %s reservation on unregistered"
522 					" nexus\n", cdb[0],
523 					core_scsi3_pr_dump_type(pr_reg_type));
524 			}
525 
526 			return 0;
527 		}
528 	} else if ((reg_only) || (all_reg)) {
529 		if (registered_nexus) {
530 			/*
531 			 * For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
532 			 * allow commands from registered nexuses.
533 			 */
534 
535 			pr_debug("Allowing implicit CDB: 0x%02x for %s"
536 				" reservation\n", cdb[0],
537 				core_scsi3_pr_dump_type(pr_reg_type));
538 
539 			return 0;
540 		}
541        } else if (we && registered_nexus) {
542                /*
543                 * Reads are allowed for Write Exclusive locks
544                 * from all registrants.
545                 */
546                if (cmd->data_direction == DMA_FROM_DEVICE) {
547                        pr_debug("Allowing READ CDB: 0x%02x for %s"
548                                " reservation\n", cdb[0],
549                                core_scsi3_pr_dump_type(pr_reg_type));
550 
551                        return 0;
552                }
553 	}
554 	pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
555 		" for %s reservation\n", transport_dump_cmd_direction(cmd),
556 		(registered_nexus) ? "" : "un",
557 		se_sess->se_node_acl->initiatorname, cdb[0],
558 		core_scsi3_pr_dump_type(pr_reg_type));
559 
560 	return 1; /* Conflict by default */
561 }
562 
563 static sense_reason_t
564 target_scsi3_pr_reservation_check(struct se_cmd *cmd)
565 {
566 	struct se_device *dev = cmd->se_dev;
567 	struct se_session *sess = cmd->se_sess;
568 	u32 pr_reg_type;
569 	bool isid_mismatch = false;
570 
571 	if (!dev->dev_pr_res_holder)
572 		return 0;
573 
574 	pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
575 	cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
576 	if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
577 		goto check_nonholder;
578 
579 	if (dev->dev_pr_res_holder->isid_present_at_reg) {
580 		if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
581 		    sess->sess_bin_isid) {
582 			isid_mismatch = true;
583 			goto check_nonholder;
584 		}
585 	}
586 
587 	return 0;
588 
589 check_nonholder:
590 	if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type, isid_mismatch))
591 		return TCM_RESERVATION_CONFLICT;
592 	return 0;
593 }
594 
595 static u32 core_scsi3_pr_generation(struct se_device *dev)
596 {
597 	u32 prg;
598 
599 	/*
600 	 * PRGeneration field shall contain the value of a 32-bit wrapping
601 	 * counter mainted by the device server.
602 	 *
603 	 * Note that this is done regardless of Active Persist across
604 	 * Target PowerLoss (APTPL)
605 	 *
606 	 * See spc4r17 section 6.3.12 READ_KEYS service action
607 	 */
608 	spin_lock(&dev->dev_reservation_lock);
609 	prg = dev->t10_pr.pr_generation++;
610 	spin_unlock(&dev->dev_reservation_lock);
611 
612 	return prg;
613 }
614 
615 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
616 	struct se_device *dev,
617 	struct se_node_acl *nacl,
618 	struct se_lun *lun,
619 	struct se_dev_entry *dest_deve,
620 	u64 mapped_lun,
621 	unsigned char *isid,
622 	u64 sa_res_key,
623 	int all_tg_pt,
624 	int aptpl)
625 {
626 	struct t10_pr_registration *pr_reg;
627 
628 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_ATOMIC);
629 	if (!pr_reg) {
630 		pr_err("Unable to allocate struct t10_pr_registration\n");
631 		return NULL;
632 	}
633 
634 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
635 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
636 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
637 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
638 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
639 	atomic_set(&pr_reg->pr_res_holders, 0);
640 	pr_reg->pr_reg_nacl = nacl;
641 	/*
642 	 * For destination registrations for ALL_TG_PT=1 and SPEC_I_PT=1,
643 	 * the se_dev_entry->pr_ref will have been already obtained by
644 	 * core_get_se_deve_from_rtpi() or __core_scsi3_alloc_registration().
645 	 *
646 	 * Otherwise, locate se_dev_entry now and obtain a reference until
647 	 * registration completes in __core_scsi3_add_registration().
648 	 */
649 	if (dest_deve) {
650 		pr_reg->pr_reg_deve = dest_deve;
651 	} else {
652 		rcu_read_lock();
653 		pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
654 		if (!pr_reg->pr_reg_deve) {
655 			rcu_read_unlock();
656 			pr_err("Unable to locate PR deve %s mapped_lun: %llu\n",
657 				nacl->initiatorname, mapped_lun);
658 			kmem_cache_free(t10_pr_reg_cache, pr_reg);
659 			return NULL;
660 		}
661 		kref_get(&pr_reg->pr_reg_deve->pr_kref);
662 		rcu_read_unlock();
663 	}
664 	pr_reg->pr_res_mapped_lun = mapped_lun;
665 	pr_reg->pr_aptpl_target_lun = lun->unpacked_lun;
666 	pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
667 	pr_reg->pr_res_key = sa_res_key;
668 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
669 	pr_reg->pr_reg_aptpl = aptpl;
670 	/*
671 	 * If an ISID value for this SCSI Initiator Port exists,
672 	 * save it to the registration now.
673 	 */
674 	if (isid != NULL) {
675 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
676 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
677 		pr_reg->isid_present_at_reg = 1;
678 	}
679 
680 	return pr_reg;
681 }
682 
683 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
684 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
685 
686 /*
687  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
688  * modes.
689  */
690 static struct t10_pr_registration *__core_scsi3_alloc_registration(
691 	struct se_device *dev,
692 	struct se_node_acl *nacl,
693 	struct se_lun *lun,
694 	struct se_dev_entry *deve,
695 	u64 mapped_lun,
696 	unsigned char *isid,
697 	u64 sa_res_key,
698 	int all_tg_pt,
699 	int aptpl)
700 {
701 	struct se_dev_entry *deve_tmp;
702 	struct se_node_acl *nacl_tmp;
703 	struct se_lun_acl *lacl_tmp;
704 	struct se_lun *lun_tmp, *next, *dest_lun;
705 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
706 	struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
707 	int ret;
708 	/*
709 	 * Create a registration for the I_T Nexus upon which the
710 	 * PROUT REGISTER was received.
711 	 */
712 	pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, lun, deve, mapped_lun,
713 						    isid, sa_res_key, all_tg_pt,
714 						    aptpl);
715 	if (!pr_reg)
716 		return NULL;
717 	/*
718 	 * Return pointer to pr_reg for ALL_TG_PT=0
719 	 */
720 	if (!all_tg_pt)
721 		return pr_reg;
722 	/*
723 	 * Create list of matching SCSI Initiator Port registrations
724 	 * for ALL_TG_PT=1
725 	 */
726 	spin_lock(&dev->se_port_lock);
727 	list_for_each_entry_safe(lun_tmp, next, &dev->dev_sep_list, lun_dev_link) {
728 		if (!percpu_ref_tryget_live(&lun_tmp->lun_ref))
729 			continue;
730 		spin_unlock(&dev->se_port_lock);
731 
732 		spin_lock(&lun_tmp->lun_deve_lock);
733 		list_for_each_entry(deve_tmp, &lun_tmp->lun_deve_list, lun_link) {
734 			/*
735 			 * This pointer will be NULL for demo mode MappedLUNs
736 			 * that have not been make explicit via a ConfigFS
737 			 * MappedLUN group for the SCSI Initiator Node ACL.
738 			 */
739 			if (!deve_tmp->se_lun_acl)
740 				continue;
741 
742 			lacl_tmp = deve_tmp->se_lun_acl;
743 			nacl_tmp = lacl_tmp->se_lun_nacl;
744 			/*
745 			 * Skip the matching struct se_node_acl that is allocated
746 			 * above..
747 			 */
748 			if (nacl == nacl_tmp)
749 				continue;
750 			/*
751 			 * Only perform PR registrations for target ports on
752 			 * the same fabric module as the REGISTER w/ ALL_TG_PT=1
753 			 * arrived.
754 			 */
755 			if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
756 				continue;
757 			/*
758 			 * Look for a matching Initiator Node ACL in ASCII format
759 			 */
760 			if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
761 				continue;
762 
763 			kref_get(&deve_tmp->pr_kref);
764 			spin_unlock(&lun_tmp->lun_deve_lock);
765 			/*
766 			 * Grab a configfs group dependency that is released
767 			 * for the exception path at label out: below, or upon
768 			 * completion of adding ALL_TG_PT=1 registrations in
769 			 * __core_scsi3_add_registration()
770 			 */
771 			ret = core_scsi3_lunacl_depend_item(deve_tmp);
772 			if (ret < 0) {
773 				pr_err("core_scsi3_lunacl_depend"
774 						"_item() failed\n");
775 				percpu_ref_put(&lun_tmp->lun_ref);
776 				kref_put(&deve_tmp->pr_kref, target_pr_kref_release);
777 				goto out;
778 			}
779 			/*
780 			 * Located a matching SCSI Initiator Port on a different
781 			 * port, allocate the pr_reg_atp and attach it to the
782 			 * pr_reg->pr_reg_atp_list that will be processed once
783 			 * the original *pr_reg is processed in
784 			 * __core_scsi3_add_registration()
785 			 */
786 			dest_lun = deve_tmp->se_lun;
787 
788 			pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
789 						nacl_tmp, dest_lun, deve_tmp,
790 						deve_tmp->mapped_lun, NULL,
791 						sa_res_key, all_tg_pt, aptpl);
792 			if (!pr_reg_atp) {
793 				percpu_ref_put(&lun_tmp->lun_ref);
794 				core_scsi3_lunacl_undepend_item(deve_tmp);
795 				goto out;
796 			}
797 
798 			list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
799 				      &pr_reg->pr_reg_atp_list);
800 			spin_lock(&lun_tmp->lun_deve_lock);
801 		}
802 		spin_unlock(&lun_tmp->lun_deve_lock);
803 
804 		spin_lock(&dev->se_port_lock);
805 		percpu_ref_put(&lun_tmp->lun_ref);
806 	}
807 	spin_unlock(&dev->se_port_lock);
808 
809 	return pr_reg;
810 out:
811 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
812 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
813 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
814 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
815 		kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
816 	}
817 	kmem_cache_free(t10_pr_reg_cache, pr_reg);
818 	return NULL;
819 }
820 
821 int core_scsi3_alloc_aptpl_registration(
822 	struct t10_reservation *pr_tmpl,
823 	u64 sa_res_key,
824 	unsigned char *i_port,
825 	unsigned char *isid,
826 	u64 mapped_lun,
827 	unsigned char *t_port,
828 	u16 tpgt,
829 	u64 target_lun,
830 	int res_holder,
831 	int all_tg_pt,
832 	u8 type)
833 {
834 	struct t10_pr_registration *pr_reg;
835 
836 	if (!i_port || !t_port || !sa_res_key) {
837 		pr_err("Illegal parameters for APTPL registration\n");
838 		return -EINVAL;
839 	}
840 
841 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
842 	if (!pr_reg) {
843 		pr_err("Unable to allocate struct t10_pr_registration\n");
844 		return -ENOMEM;
845 	}
846 
847 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
848 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
849 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
850 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
851 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
852 	atomic_set(&pr_reg->pr_res_holders, 0);
853 	pr_reg->pr_reg_nacl = NULL;
854 	pr_reg->pr_reg_deve = NULL;
855 	pr_reg->pr_res_mapped_lun = mapped_lun;
856 	pr_reg->pr_aptpl_target_lun = target_lun;
857 	pr_reg->pr_res_key = sa_res_key;
858 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
859 	pr_reg->pr_reg_aptpl = 1;
860 	pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
861 	pr_reg->pr_res_type = type;
862 	/*
863 	 * If an ISID value had been saved in APTPL metadata for this
864 	 * SCSI Initiator Port, restore it now.
865 	 */
866 	if (isid != NULL) {
867 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
868 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
869 		pr_reg->isid_present_at_reg = 1;
870 	}
871 	/*
872 	 * Copy the i_port and t_port information from caller.
873 	 */
874 	snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
875 	snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
876 	pr_reg->pr_reg_tpgt = tpgt;
877 	/*
878 	 * Set pr_res_holder from caller, the pr_reg who is the reservation
879 	 * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
880 	 * the Initiator Node LUN ACL from the fabric module is created for
881 	 * this registration.
882 	 */
883 	pr_reg->pr_res_holder = res_holder;
884 
885 	list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
886 	pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
887 			" metadata\n", (res_holder) ? "+reservation" : "");
888 	return 0;
889 }
890 
891 static void core_scsi3_aptpl_reserve(
892 	struct se_device *dev,
893 	struct se_portal_group *tpg,
894 	struct se_node_acl *node_acl,
895 	struct t10_pr_registration *pr_reg)
896 {
897 	char i_buf[PR_REG_ISID_ID_LEN] = { };
898 
899 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
900 
901 	spin_lock(&dev->dev_reservation_lock);
902 	dev->dev_pr_res_holder = pr_reg;
903 	spin_unlock(&dev->dev_reservation_lock);
904 
905 	pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
906 		" new reservation holder TYPE: %s ALL_TG_PT: %d\n",
907 		tpg->se_tpg_tfo->fabric_name,
908 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
909 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
910 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
911 		tpg->se_tpg_tfo->fabric_name, node_acl->initiatorname,
912 		i_buf);
913 }
914 
915 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
916 				struct t10_pr_registration *, enum register_type, int);
917 
918 static int __core_scsi3_check_aptpl_registration(
919 	struct se_device *dev,
920 	struct se_portal_group *tpg,
921 	struct se_lun *lun,
922 	u64 target_lun,
923 	struct se_node_acl *nacl,
924 	u64 mapped_lun)
925 {
926 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
927 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
928 	unsigned char i_port[PR_APTPL_MAX_IPORT_LEN] = { };
929 	unsigned char t_port[PR_APTPL_MAX_TPORT_LEN] = { };
930 	u16 tpgt;
931 
932 	/*
933 	 * Copy Initiator Port information from struct se_node_acl
934 	 */
935 	snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
936 	snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
937 			tpg->se_tpg_tfo->tpg_get_wwn(tpg));
938 	tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
939 	/*
940 	 * Look for the matching registrations+reservation from those
941 	 * created from APTPL metadata.  Note that multiple registrations
942 	 * may exist for fabrics that use ISIDs in their SCSI Initiator Port
943 	 * TransportIDs.
944 	 */
945 	spin_lock(&pr_tmpl->aptpl_reg_lock);
946 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
947 				pr_reg_aptpl_list) {
948 
949 		if (!strcmp(pr_reg->pr_iport, i_port) &&
950 		     (pr_reg->pr_res_mapped_lun == mapped_lun) &&
951 		    !(strcmp(pr_reg->pr_tport, t_port)) &&
952 		     (pr_reg->pr_reg_tpgt == tpgt) &&
953 		     (pr_reg->pr_aptpl_target_lun == target_lun)) {
954 			/*
955 			 * Obtain the ->pr_reg_deve pointer + reference, that
956 			 * is released by __core_scsi3_add_registration() below.
957 			 */
958 			rcu_read_lock();
959 			pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
960 			if (!pr_reg->pr_reg_deve) {
961 				pr_err("Unable to locate PR APTPL %s mapped_lun:"
962 					" %llu\n", nacl->initiatorname, mapped_lun);
963 				rcu_read_unlock();
964 				continue;
965 			}
966 			kref_get(&pr_reg->pr_reg_deve->pr_kref);
967 			rcu_read_unlock();
968 
969 			pr_reg->pr_reg_nacl = nacl;
970 			pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
971 			list_del(&pr_reg->pr_reg_aptpl_list);
972 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
973 			/*
974 			 * At this point all of the pointers in *pr_reg will
975 			 * be setup, so go ahead and add the registration.
976 			 */
977 			__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
978 			/*
979 			 * If this registration is the reservation holder,
980 			 * make that happen now..
981 			 */
982 			if (pr_reg->pr_res_holder)
983 				core_scsi3_aptpl_reserve(dev, tpg,
984 						nacl, pr_reg);
985 			/*
986 			 * Reenable pr_aptpl_active to accept new metadata
987 			 * updates once the SCSI device is active again..
988 			 */
989 			spin_lock(&pr_tmpl->aptpl_reg_lock);
990 			pr_tmpl->pr_aptpl_active = 1;
991 		}
992 	}
993 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
994 
995 	return 0;
996 }
997 
998 int core_scsi3_check_aptpl_registration(
999 	struct se_device *dev,
1000 	struct se_portal_group *tpg,
1001 	struct se_lun *lun,
1002 	struct se_node_acl *nacl,
1003 	u64 mapped_lun)
1004 {
1005 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
1006 		return 0;
1007 
1008 	return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
1009 						     lun->unpacked_lun, nacl,
1010 						     mapped_lun);
1011 }
1012 
1013 static void __core_scsi3_dump_registration(
1014 	const struct target_core_fabric_ops *tfo,
1015 	struct se_device *dev,
1016 	struct se_node_acl *nacl,
1017 	struct t10_pr_registration *pr_reg,
1018 	enum register_type register_type)
1019 {
1020 	struct se_portal_group *se_tpg = nacl->se_tpg;
1021 	char i_buf[PR_REG_ISID_ID_LEN] = { };
1022 
1023 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1024 
1025 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
1026 		" Node: %s%s\n", tfo->fabric_name, (register_type == REGISTER_AND_MOVE) ?
1027 		"_AND_MOVE" : (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ?
1028 		"_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
1029 		i_buf);
1030 	pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
1031 		 tfo->fabric_name, tfo->tpg_get_wwn(se_tpg),
1032 		tfo->tpg_get_tag(se_tpg));
1033 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1034 		" Port(s)\n",  tfo->fabric_name,
1035 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1036 		dev->transport->name);
1037 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1038 		" 0x%08x  APTPL: %d\n", tfo->fabric_name,
1039 		pr_reg->pr_res_key, pr_reg->pr_res_generation,
1040 		pr_reg->pr_reg_aptpl);
1041 }
1042 
1043 static void __core_scsi3_add_registration(
1044 	struct se_device *dev,
1045 	struct se_node_acl *nacl,
1046 	struct t10_pr_registration *pr_reg,
1047 	enum register_type register_type,
1048 	int register_move)
1049 {
1050 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1051 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1052 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1053 	struct se_dev_entry *deve;
1054 
1055 	/*
1056 	 * Increment PRgeneration counter for struct se_device upon a successful
1057 	 * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1058 	 *
1059 	 * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1060 	 * action, the struct se_device->dev_reservation_lock will already be held,
1061 	 * so we do not call core_scsi3_pr_generation() which grabs the lock
1062 	 * for the REGISTER.
1063 	 */
1064 	pr_reg->pr_res_generation = (register_move) ?
1065 			dev->t10_pr.pr_generation++ :
1066 			core_scsi3_pr_generation(dev);
1067 
1068 	spin_lock(&pr_tmpl->registration_lock);
1069 	list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1070 
1071 	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1072 	spin_unlock(&pr_tmpl->registration_lock);
1073 	/*
1074 	 * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1075 	 */
1076 	if (!pr_reg->pr_reg_all_tg_pt || register_move)
1077 		goto out;
1078 	/*
1079 	 * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1080 	 * allocated in __core_scsi3_alloc_registration()
1081 	 */
1082 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1083 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1084 		struct se_node_acl *nacl_tmp = pr_reg_tmp->pr_reg_nacl;
1085 
1086 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1087 
1088 		pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1089 
1090 		spin_lock(&pr_tmpl->registration_lock);
1091 		list_add_tail(&pr_reg_tmp->pr_reg_list,
1092 			      &pr_tmpl->registration_list);
1093 
1094 		__core_scsi3_dump_registration(tfo, dev, nacl_tmp, pr_reg_tmp,
1095 					       register_type);
1096 		spin_unlock(&pr_tmpl->registration_lock);
1097 		/*
1098 		 * Drop configfs group dependency reference and deve->pr_kref
1099 		 * obtained from  __core_scsi3_alloc_registration() code.
1100 		 */
1101 		rcu_read_lock();
1102 		deve = pr_reg_tmp->pr_reg_deve;
1103 		if (deve) {
1104 			set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1105 			core_scsi3_lunacl_undepend_item(deve);
1106 			pr_reg_tmp->pr_reg_deve = NULL;
1107 		}
1108 		rcu_read_unlock();
1109 	}
1110 out:
1111 	/*
1112 	 * Drop deve->pr_kref obtained in __core_scsi3_do_alloc_registration()
1113 	 */
1114 	rcu_read_lock();
1115 	deve = pr_reg->pr_reg_deve;
1116 	if (deve) {
1117 		set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1118 		kref_put(&deve->pr_kref, target_pr_kref_release);
1119 		pr_reg->pr_reg_deve = NULL;
1120 	}
1121 	rcu_read_unlock();
1122 }
1123 
1124 static int core_scsi3_alloc_registration(
1125 	struct se_device *dev,
1126 	struct se_node_acl *nacl,
1127 	struct se_lun *lun,
1128 	struct se_dev_entry *deve,
1129 	u64 mapped_lun,
1130 	unsigned char *isid,
1131 	u64 sa_res_key,
1132 	int all_tg_pt,
1133 	int aptpl,
1134 	enum register_type register_type,
1135 	int register_move)
1136 {
1137 	struct t10_pr_registration *pr_reg;
1138 
1139 	pr_reg = __core_scsi3_alloc_registration(dev, nacl, lun, deve, mapped_lun,
1140 						 isid, sa_res_key, all_tg_pt,
1141 						 aptpl);
1142 	if (!pr_reg)
1143 		return -EPERM;
1144 
1145 	__core_scsi3_add_registration(dev, nacl, pr_reg,
1146 			register_type, register_move);
1147 	return 0;
1148 }
1149 
1150 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1151 	struct se_device *dev,
1152 	struct se_node_acl *nacl,
1153 	unsigned char *isid)
1154 {
1155 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1156 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1157 
1158 	spin_lock(&pr_tmpl->registration_lock);
1159 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1160 			&pr_tmpl->registration_list, pr_reg_list) {
1161 		/*
1162 		 * First look for a matching struct se_node_acl
1163 		 */
1164 		if (pr_reg->pr_reg_nacl != nacl)
1165 			continue;
1166 
1167 		/*
1168 		 * If this registration does NOT contain a fabric provided
1169 		 * ISID, then we have found a match.
1170 		 */
1171 		if (!pr_reg->isid_present_at_reg) {
1172 			atomic_inc_mb(&pr_reg->pr_res_holders);
1173 			spin_unlock(&pr_tmpl->registration_lock);
1174 			return pr_reg;
1175 		}
1176 		/*
1177 		 * If the *pr_reg contains a fabric defined ISID for multi-value
1178 		 * SCSI Initiator Port TransportIDs, then we expect a valid
1179 		 * matching ISID to be provided by the local SCSI Initiator Port.
1180 		 */
1181 		if (!isid)
1182 			continue;
1183 		if (strcmp(isid, pr_reg->pr_reg_isid))
1184 			continue;
1185 
1186 		atomic_inc_mb(&pr_reg->pr_res_holders);
1187 		spin_unlock(&pr_tmpl->registration_lock);
1188 		return pr_reg;
1189 	}
1190 	spin_unlock(&pr_tmpl->registration_lock);
1191 
1192 	return NULL;
1193 }
1194 
1195 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1196 	struct se_device *dev,
1197 	struct se_node_acl *nacl,
1198 	struct se_session *sess)
1199 {
1200 	struct se_portal_group *tpg = nacl->se_tpg;
1201 	unsigned char buf[PR_REG_ISID_LEN] = { };
1202 	unsigned char *isid_ptr = NULL;
1203 
1204 	if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1205 		tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1206 					PR_REG_ISID_LEN);
1207 		isid_ptr = &buf[0];
1208 	}
1209 
1210 	return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1211 }
1212 
1213 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1214 {
1215 	atomic_dec_mb(&pr_reg->pr_res_holders);
1216 }
1217 
1218 static int core_scsi3_check_implicit_release(
1219 	struct se_device *dev,
1220 	struct t10_pr_registration *pr_reg)
1221 {
1222 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1223 	struct t10_pr_registration *pr_res_holder;
1224 	int ret = 0;
1225 
1226 	spin_lock(&dev->dev_reservation_lock);
1227 	pr_res_holder = dev->dev_pr_res_holder;
1228 	if (!pr_res_holder) {
1229 		spin_unlock(&dev->dev_reservation_lock);
1230 		return ret;
1231 	}
1232 	if (pr_res_holder == pr_reg) {
1233 		/*
1234 		 * Perform an implicit RELEASE if the registration that
1235 		 * is being released is holding the reservation.
1236 		 *
1237 		 * From spc4r17, section 5.7.11.1:
1238 		 *
1239 		 * e) If the I_T nexus is the persistent reservation holder
1240 		 *    and the persistent reservation is not an all registrants
1241 		 *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1242 		 *    service action or REGISTER AND  IGNORE EXISTING KEY
1243 		 *    service action with the SERVICE ACTION RESERVATION KEY
1244 		 *    field set to zero (see 5.7.11.3).
1245 		 */
1246 		__core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0, 1);
1247 		ret = 1;
1248 		/*
1249 		 * For 'All Registrants' reservation types, all existing
1250 		 * registrations are still processed as reservation holders
1251 		 * in core_scsi3_pr_seq_non_holder() after the initial
1252 		 * reservation holder is implicitly released here.
1253 		 */
1254 	} else if (pr_reg->pr_reg_all_tg_pt &&
1255 		  (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1256 			  pr_reg->pr_reg_nacl->initiatorname)) &&
1257 		  (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1258 		pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1259 			" UNREGISTER while existing reservation with matching"
1260 			" key 0x%016Lx is present from another SCSI Initiator"
1261 			" Port\n", pr_reg->pr_res_key);
1262 		ret = -EPERM;
1263 	}
1264 	spin_unlock(&dev->dev_reservation_lock);
1265 
1266 	return ret;
1267 }
1268 
1269 static void __core_scsi3_free_registration(
1270 	struct se_device *dev,
1271 	struct t10_pr_registration *pr_reg,
1272 	struct list_head *preempt_and_abort_list,
1273 	int dec_holders)
1274 	__releases(&pr_tmpl->registration_lock)
1275 	__acquires(&pr_tmpl->registration_lock)
1276 {
1277 	const struct target_core_fabric_ops *tfo =
1278 			pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1279 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1280 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1281 	struct se_dev_entry *deve;
1282 	char i_buf[PR_REG_ISID_ID_LEN] = { };
1283 
1284 	lockdep_assert_held(&pr_tmpl->registration_lock);
1285 
1286 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1287 
1288 	if (!list_empty(&pr_reg->pr_reg_list))
1289 		list_del(&pr_reg->pr_reg_list);
1290 	/*
1291 	 * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1292 	 * so call core_scsi3_put_pr_reg() to decrement our reference.
1293 	 */
1294 	if (dec_holders)
1295 		core_scsi3_put_pr_reg(pr_reg);
1296 
1297 	spin_unlock(&pr_tmpl->registration_lock);
1298 	/*
1299 	 * Wait until all reference from any other I_T nexuses for this
1300 	 * *pr_reg have been released.  Because list_del() is called above,
1301 	 * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1302 	 * count back to zero, and we release *pr_reg.
1303 	 */
1304 	while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1305 		pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1306 				tfo->fabric_name);
1307 		cpu_relax();
1308 	}
1309 
1310 	rcu_read_lock();
1311 	deve = target_nacl_find_deve(nacl, pr_reg->pr_res_mapped_lun);
1312 	if (deve)
1313 		clear_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
1314 	rcu_read_unlock();
1315 
1316 	spin_lock(&pr_tmpl->registration_lock);
1317 	pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1318 		" Node: %s%s\n", tfo->fabric_name,
1319 		pr_reg->pr_reg_nacl->initiatorname,
1320 		i_buf);
1321 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1322 		" Port(s)\n", tfo->fabric_name,
1323 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1324 		dev->transport->name);
1325 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1326 		" 0x%08x\n", tfo->fabric_name, pr_reg->pr_res_key,
1327 		pr_reg->pr_res_generation);
1328 
1329 	if (!preempt_and_abort_list) {
1330 		pr_reg->pr_reg_deve = NULL;
1331 		pr_reg->pr_reg_nacl = NULL;
1332 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1333 		return;
1334 	}
1335 	/*
1336 	 * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1337 	 * are released once the ABORT_TASK_SET has completed..
1338 	 */
1339 	list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1340 }
1341 
1342 void core_scsi3_free_pr_reg_from_nacl(
1343 	struct se_device *dev,
1344 	struct se_node_acl *nacl)
1345 {
1346 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1347 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1348 	bool free_reg = false;
1349 	/*
1350 	 * If the passed se_node_acl matches the reservation holder,
1351 	 * release the reservation.
1352 	 */
1353 	spin_lock(&dev->dev_reservation_lock);
1354 	pr_res_holder = dev->dev_pr_res_holder;
1355 	if ((pr_res_holder != NULL) &&
1356 	    (pr_res_holder->pr_reg_nacl == nacl)) {
1357 		__core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0, 1);
1358 		free_reg = true;
1359 	}
1360 	spin_unlock(&dev->dev_reservation_lock);
1361 	/*
1362 	 * Release any registration associated with the struct se_node_acl.
1363 	 */
1364 	spin_lock(&pr_tmpl->registration_lock);
1365 	if (pr_res_holder && free_reg)
1366 		__core_scsi3_free_registration(dev, pr_res_holder, NULL, 0);
1367 
1368 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1369 			&pr_tmpl->registration_list, pr_reg_list) {
1370 
1371 		if (pr_reg->pr_reg_nacl != nacl)
1372 			continue;
1373 
1374 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1375 	}
1376 	spin_unlock(&pr_tmpl->registration_lock);
1377 }
1378 
1379 void core_scsi3_free_all_registrations(
1380 	struct se_device *dev)
1381 {
1382 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1383 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1384 
1385 	spin_lock(&dev->dev_reservation_lock);
1386 	pr_res_holder = dev->dev_pr_res_holder;
1387 	if (pr_res_holder != NULL) {
1388 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1389 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
1390 						  pr_res_holder, 0, 0);
1391 	}
1392 	spin_unlock(&dev->dev_reservation_lock);
1393 
1394 	spin_lock(&pr_tmpl->registration_lock);
1395 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1396 			&pr_tmpl->registration_list, pr_reg_list) {
1397 
1398 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1399 	}
1400 	spin_unlock(&pr_tmpl->registration_lock);
1401 
1402 	spin_lock(&pr_tmpl->aptpl_reg_lock);
1403 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1404 				pr_reg_aptpl_list) {
1405 		list_del(&pr_reg->pr_reg_aptpl_list);
1406 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1407 	}
1408 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
1409 }
1410 
1411 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1412 {
1413 	return target_depend_item(&tpg->tpg_group.cg_item);
1414 }
1415 
1416 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1417 {
1418 	target_undepend_item(&tpg->tpg_group.cg_item);
1419 	atomic_dec_mb(&tpg->tpg_pr_ref_count);
1420 }
1421 
1422 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1423 {
1424 	if (nacl->dynamic_node_acl)
1425 		return 0;
1426 	return target_depend_item(&nacl->acl_group.cg_item);
1427 }
1428 
1429 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1430 {
1431 	if (!nacl->dynamic_node_acl)
1432 		target_undepend_item(&nacl->acl_group.cg_item);
1433 	atomic_dec_mb(&nacl->acl_pr_ref_count);
1434 }
1435 
1436 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1437 {
1438 	/*
1439 	 * For nacl->dynamic_node_acl=1
1440 	 */
1441 	if (!se_deve->se_lun_acl)
1442 		return 0;
1443 
1444 	return target_depend_item(&se_deve->se_lun_acl->se_lun_group.cg_item);
1445 }
1446 
1447 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1448 {
1449 	/*
1450 	 * For nacl->dynamic_node_acl=1
1451 	 */
1452 	if (!se_deve->se_lun_acl) {
1453 		kref_put(&se_deve->pr_kref, target_pr_kref_release);
1454 		return;
1455 	}
1456 
1457 	target_undepend_item(&se_deve->se_lun_acl->se_lun_group.cg_item);
1458 	kref_put(&se_deve->pr_kref, target_pr_kref_release);
1459 }
1460 
1461 static sense_reason_t
1462 core_scsi3_decode_spec_i_port(
1463 	struct se_cmd *cmd,
1464 	struct se_portal_group *tpg,
1465 	unsigned char *l_isid,
1466 	u64 sa_res_key,
1467 	int all_tg_pt,
1468 	int aptpl)
1469 {
1470 	struct se_device *dev = cmd->se_dev;
1471 	struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1472 	struct se_session *se_sess = cmd->se_sess;
1473 	struct se_node_acl *dest_node_acl = NULL;
1474 	struct se_dev_entry *dest_se_deve = NULL;
1475 	struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1476 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1477 	LIST_HEAD(tid_dest_list);
1478 	struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1479 	unsigned char *buf, *ptr, proto_ident;
1480 	const unsigned char *i_str = NULL;
1481 	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
1482 	sense_reason_t ret;
1483 	u32 tpdl, tid_len = 0;
1484 	u32 dest_rtpi = 0;
1485 
1486 	/*
1487 	 * Allocate a struct pr_transport_id_holder and setup the
1488 	 * local_node_acl pointer and add to struct list_head tid_dest_list
1489 	 * for add registration processing in the loop of tid_dest_list below.
1490 	 */
1491 	tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1492 	if (!tidh_new) {
1493 		pr_err("Unable to allocate tidh_new\n");
1494 		return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1495 	}
1496 	INIT_LIST_HEAD(&tidh_new->dest_list);
1497 	tidh_new->dest_tpg = tpg;
1498 	tidh_new->dest_node_acl = se_sess->se_node_acl;
1499 
1500 	local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1501 				se_sess->se_node_acl, cmd->se_lun,
1502 				NULL, cmd->orig_fe_lun, l_isid,
1503 				sa_res_key, all_tg_pt, aptpl);
1504 	if (!local_pr_reg) {
1505 		kfree(tidh_new);
1506 		return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1507 	}
1508 
1509 	if (core_scsi3_lunacl_depend_item(local_pr_reg->pr_reg_deve)) {
1510 		kfree(tidh_new);
1511 		kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
1512 			 target_pr_kref_release);
1513 		kmem_cache_free(t10_pr_reg_cache, local_pr_reg);
1514 		return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1515 	}
1516 
1517 	tidh_new->dest_pr_reg = local_pr_reg;
1518 	list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1519 
1520 	if (cmd->data_length < 28) {
1521 		pr_warn("SPC-PR: Received PR OUT parameter list"
1522 			" length too small: %u\n", cmd->data_length);
1523 		ret = TCM_INVALID_PARAMETER_LIST;
1524 		goto out;
1525 	}
1526 
1527 	buf = transport_kmap_data_sg(cmd);
1528 	if (!buf) {
1529 		ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1530 		goto out;
1531 	}
1532 
1533 	/*
1534 	 * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1535 	 * first extract TransportID Parameter Data Length, and make sure
1536 	 * the value matches up to the SCSI expected data transfer length.
1537 	 */
1538 	tpdl = get_unaligned_be32(&buf[24]);
1539 
1540 	if ((tpdl + 28) != cmd->data_length) {
1541 		pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1542 			" does not equal CDB data_length: %u\n", tpdl,
1543 			cmd->data_length);
1544 		ret = TCM_INVALID_PARAMETER_LIST;
1545 		goto out_unmap;
1546 	}
1547 	/*
1548 	 * Start processing the received transport IDs using the
1549 	 * receiving I_T Nexus portal's fabric dependent methods to
1550 	 * obtain the SCSI Initiator Port/Device Identifiers.
1551 	 */
1552 	ptr = &buf[28];
1553 
1554 	while (tpdl > 0) {
1555 		struct se_lun *dest_lun, *tmp_lun;
1556 
1557 		proto_ident = (ptr[0] & 0x0f);
1558 		dest_tpg = NULL;
1559 
1560 		spin_lock(&dev->se_port_lock);
1561 		list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
1562 			tmp_tpg = tmp_lun->lun_tpg;
1563 
1564 			/*
1565 			 * Look for the matching proto_ident provided by
1566 			 * the received TransportID
1567 			 */
1568 			if (tmp_tpg->proto_id != proto_ident)
1569 				continue;
1570 			dest_rtpi = tmp_lun->lun_rtpi;
1571 
1572 			iport_ptr = NULL;
1573 			i_str = target_parse_pr_out_transport_id(tmp_tpg,
1574 					ptr, &tid_len, &iport_ptr);
1575 			if (!i_str)
1576 				continue;
1577 			/*
1578 			 * Determine if this SCSI device server requires that
1579 			 * SCSI Intiatior TransportID w/ ISIDs is enforced
1580 			 * for fabric modules (iSCSI) requiring them.
1581 			 */
1582 			if (tpg->se_tpg_tfo->sess_get_initiator_sid &&
1583 			    dev->dev_attrib.enforce_pr_isids &&
1584 			    !iport_ptr) {
1585 				pr_warn("SPC-PR: enforce_pr_isids is set but a isid has not been sent in the SPEC_I_PT data for %s.",
1586 					i_str);
1587 				ret = TCM_INVALID_PARAMETER_LIST;
1588 				spin_unlock(&dev->se_port_lock);
1589 				goto out_unmap;
1590 			}
1591 
1592 			atomic_inc_mb(&tmp_tpg->tpg_pr_ref_count);
1593 			spin_unlock(&dev->se_port_lock);
1594 
1595 			if (core_scsi3_tpg_depend_item(tmp_tpg)) {
1596 				pr_err(" core_scsi3_tpg_depend_item()"
1597 					" for tmp_tpg\n");
1598 				atomic_dec_mb(&tmp_tpg->tpg_pr_ref_count);
1599 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1600 				goto out_unmap;
1601 			}
1602 			/*
1603 			 * Locate the destination initiator ACL to be registered
1604 			 * from the decoded fabric module specific TransportID
1605 			 * at *i_str.
1606 			 */
1607 			mutex_lock(&tmp_tpg->acl_node_mutex);
1608 			dest_node_acl = __core_tpg_get_initiator_node_acl(
1609 						tmp_tpg, i_str);
1610 			if (dest_node_acl)
1611 				atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
1612 			mutex_unlock(&tmp_tpg->acl_node_mutex);
1613 
1614 			if (!dest_node_acl) {
1615 				core_scsi3_tpg_undepend_item(tmp_tpg);
1616 				spin_lock(&dev->se_port_lock);
1617 				continue;
1618 			}
1619 
1620 			if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
1621 				pr_err("configfs_depend_item() failed"
1622 					" for dest_node_acl->acl_group\n");
1623 				atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
1624 				core_scsi3_tpg_undepend_item(tmp_tpg);
1625 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1626 				goto out_unmap;
1627 			}
1628 
1629 			dest_tpg = tmp_tpg;
1630 			pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s Port RTPI: %u\n",
1631 				dest_tpg->se_tpg_tfo->fabric_name,
1632 				dest_node_acl->initiatorname, dest_rtpi);
1633 
1634 			spin_lock(&dev->se_port_lock);
1635 			break;
1636 		}
1637 		spin_unlock(&dev->se_port_lock);
1638 
1639 		if (!dest_tpg) {
1640 			pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1641 					" dest_tpg\n");
1642 			ret = TCM_INVALID_PARAMETER_LIST;
1643 			goto out_unmap;
1644 		}
1645 
1646 		pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1647 			" tid_len: %d for %s + %s\n",
1648 			dest_tpg->se_tpg_tfo->fabric_name, cmd->data_length,
1649 			tpdl, tid_len, i_str, iport_ptr);
1650 
1651 		if (tid_len > tpdl) {
1652 			pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1653 				" %u for Transport ID: %s\n", tid_len, ptr);
1654 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1655 			core_scsi3_tpg_undepend_item(dest_tpg);
1656 			ret = TCM_INVALID_PARAMETER_LIST;
1657 			goto out_unmap;
1658 		}
1659 		/*
1660 		 * Locate the desintation struct se_dev_entry pointer for matching
1661 		 * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1662 		 * Target Port.
1663 		 */
1664 		dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1665 					dest_rtpi);
1666 		if (!dest_se_deve) {
1667 			pr_err("Unable to locate %s dest_se_deve from destination RTPI: %u\n",
1668 				dest_tpg->se_tpg_tfo->fabric_name,
1669 				dest_rtpi);
1670 
1671 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1672 			core_scsi3_tpg_undepend_item(dest_tpg);
1673 			ret = TCM_INVALID_PARAMETER_LIST;
1674 			goto out_unmap;
1675 		}
1676 
1677 		if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
1678 			pr_err("core_scsi3_lunacl_depend_item()"
1679 					" failed\n");
1680 			kref_put(&dest_se_deve->pr_kref, target_pr_kref_release);
1681 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1682 			core_scsi3_tpg_undepend_item(dest_tpg);
1683 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1684 			goto out_unmap;
1685 		}
1686 
1687 		pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1688 			" dest_se_deve mapped_lun: %llu\n",
1689 			dest_tpg->se_tpg_tfo->fabric_name,
1690 			dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1691 
1692 		/*
1693 		 * Skip any TransportIDs that already have a registration for
1694 		 * this target port.
1695 		 */
1696 		pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1697 					iport_ptr);
1698 		if (pr_reg_e) {
1699 			core_scsi3_put_pr_reg(pr_reg_e);
1700 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1701 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1702 			core_scsi3_tpg_undepend_item(dest_tpg);
1703 			ptr += tid_len;
1704 			tpdl -= tid_len;
1705 			tid_len = 0;
1706 			continue;
1707 		}
1708 		/*
1709 		 * Allocate a struct pr_transport_id_holder and setup
1710 		 * the dest_node_acl and dest_se_deve pointers for the
1711 		 * loop below.
1712 		 */
1713 		tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1714 				GFP_KERNEL);
1715 		if (!tidh_new) {
1716 			pr_err("Unable to allocate tidh_new\n");
1717 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1718 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1719 			core_scsi3_tpg_undepend_item(dest_tpg);
1720 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1721 			goto out_unmap;
1722 		}
1723 		INIT_LIST_HEAD(&tidh_new->dest_list);
1724 		tidh_new->dest_tpg = dest_tpg;
1725 		tidh_new->dest_node_acl = dest_node_acl;
1726 		tidh_new->dest_se_deve = dest_se_deve;
1727 
1728 		/*
1729 		 * Allocate, but do NOT add the registration for the
1730 		 * TransportID referenced SCSI Initiator port.  This
1731 		 * done because of the following from spc4r17 in section
1732 		 * 6.14.3 wrt SPEC_I_PT:
1733 		 *
1734 		 * "If a registration fails for any initiator port (e.g., if th
1735 		 * logical unit does not have enough resources available to
1736 		 * hold the registration information), no registrations shall be
1737 		 * made, and the command shall be terminated with
1738 		 * CHECK CONDITION status."
1739 		 *
1740 		 * That means we call __core_scsi3_alloc_registration() here,
1741 		 * and then call __core_scsi3_add_registration() in the
1742 		 * 2nd loop which will never fail.
1743 		 */
1744 		dest_lun = dest_se_deve->se_lun;
1745 
1746 		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1747 					dest_node_acl, dest_lun, dest_se_deve,
1748 					dest_se_deve->mapped_lun, iport_ptr,
1749 					sa_res_key, all_tg_pt, aptpl);
1750 		if (!dest_pr_reg) {
1751 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1752 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1753 			core_scsi3_tpg_undepend_item(dest_tpg);
1754 			kfree(tidh_new);
1755 			ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1756 			goto out_unmap;
1757 		}
1758 		tidh_new->dest_pr_reg = dest_pr_reg;
1759 		list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1760 
1761 		ptr += tid_len;
1762 		tpdl -= tid_len;
1763 		tid_len = 0;
1764 
1765 	}
1766 
1767 	transport_kunmap_data_sg(cmd);
1768 
1769 	/*
1770 	 * Go ahead and create a registrations from tid_dest_list for the
1771 	 * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1772 	 * and dest_se_deve.
1773 	 *
1774 	 * The SA Reservation Key from the PROUT is set for the
1775 	 * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1776 	 * means that the TransportID Initiator port will be
1777 	 * registered on all of the target ports in the SCSI target device
1778 	 * ALL_TG_PT=0 means the registration will only be for the
1779 	 * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1780 	 * was received.
1781 	 */
1782 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1783 		dest_tpg = tidh->dest_tpg;
1784 		dest_node_acl = tidh->dest_node_acl;
1785 		dest_se_deve = tidh->dest_se_deve;
1786 		dest_pr_reg = tidh->dest_pr_reg;
1787 
1788 		list_del(&tidh->dest_list);
1789 		kfree(tidh);
1790 
1791 		memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1792 		core_pr_dump_initiator_port(dest_pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1793 
1794 		__core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1795 					dest_pr_reg, 0, 0);
1796 
1797 		pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1798 			" registered Transport ID for Node: %s%s Mapped LUN:"
1799 			" %llu\n", dest_tpg->se_tpg_tfo->fabric_name,
1800 			dest_node_acl->initiatorname, i_buf, (dest_se_deve) ?
1801 			dest_se_deve->mapped_lun : 0);
1802 
1803 		if (dest_pr_reg == local_pr_reg)
1804 			continue;
1805 
1806 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1807 		core_scsi3_tpg_undepend_item(dest_tpg);
1808 	}
1809 
1810 	return 0;
1811 out_unmap:
1812 	transport_kunmap_data_sg(cmd);
1813 out:
1814 	/*
1815 	 * For the failure case, release everything from tid_dest_list
1816 	 * including *dest_pr_reg and the configfs dependances..
1817 	 */
1818 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1819 		bool is_local = false;
1820 
1821 		dest_tpg = tidh->dest_tpg;
1822 		dest_node_acl = tidh->dest_node_acl;
1823 		dest_se_deve = tidh->dest_se_deve;
1824 		dest_pr_reg = tidh->dest_pr_reg;
1825 
1826 		if (dest_pr_reg == local_pr_reg)
1827 			is_local = true;
1828 
1829 		list_del(&tidh->dest_list);
1830 		kfree(tidh);
1831 		/*
1832 		 * Release any extra ALL_TG_PT=1 registrations for
1833 		 * the SPEC_I_PT=1 case.
1834 		 */
1835 		list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1836 				&dest_pr_reg->pr_reg_atp_list,
1837 				pr_reg_atp_mem_list) {
1838 			list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1839 			core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1840 			kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1841 		}
1842 
1843 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1844 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1845 
1846 		if (is_local)
1847 			continue;
1848 
1849 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1850 		core_scsi3_tpg_undepend_item(dest_tpg);
1851 	}
1852 	return ret;
1853 }
1854 
1855 static int core_scsi3_update_aptpl_buf(
1856 	struct se_device *dev,
1857 	unsigned char *buf,
1858 	u32 pr_aptpl_buf_len)
1859 {
1860 	struct se_portal_group *tpg;
1861 	struct t10_pr_registration *pr_reg;
1862 	unsigned char tmp[512], isid_buf[32];
1863 	ssize_t len = 0;
1864 	int reg_count = 0;
1865 	int ret = 0;
1866 
1867 	spin_lock(&dev->dev_reservation_lock);
1868 	spin_lock(&dev->t10_pr.registration_lock);
1869 	/*
1870 	 * Walk the registration list..
1871 	 */
1872 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
1873 			pr_reg_list) {
1874 
1875 		tmp[0] = '\0';
1876 		isid_buf[0] = '\0';
1877 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1878 		/*
1879 		 * Write out any ISID value to APTPL metadata that was included
1880 		 * in the original registration.
1881 		 */
1882 		if (pr_reg->isid_present_at_reg)
1883 			snprintf(isid_buf, 32, "initiator_sid=%s\n",
1884 					pr_reg->pr_reg_isid);
1885 		/*
1886 		 * Include special metadata if the pr_reg matches the
1887 		 * reservation holder.
1888 		 */
1889 		if (dev->dev_pr_res_holder == pr_reg) {
1890 			snprintf(tmp, 512, "PR_REG_START: %d"
1891 				"\ninitiator_fabric=%s\n"
1892 				"initiator_node=%s\n%s"
1893 				"sa_res_key=%llu\n"
1894 				"res_holder=1\nres_type=%02x\n"
1895 				"res_scope=%02x\nres_all_tg_pt=%d\n"
1896 				"mapped_lun=%llu\n", reg_count,
1897 				tpg->se_tpg_tfo->fabric_name,
1898 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1899 				pr_reg->pr_res_key, pr_reg->pr_res_type,
1900 				pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1901 				pr_reg->pr_res_mapped_lun);
1902 		} else {
1903 			snprintf(tmp, 512, "PR_REG_START: %d\n"
1904 				"initiator_fabric=%s\ninitiator_node=%s\n%s"
1905 				"sa_res_key=%llu\nres_holder=0\n"
1906 				"res_all_tg_pt=%d\nmapped_lun=%llu\n",
1907 				reg_count, tpg->se_tpg_tfo->fabric_name,
1908 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1909 				pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1910 				pr_reg->pr_res_mapped_lun);
1911 		}
1912 
1913 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1914 			pr_err("Unable to update renaming APTPL metadata,"
1915 			       " reallocating larger buffer\n");
1916 			ret = -EMSGSIZE;
1917 			goto out;
1918 		}
1919 		len += sprintf(buf+len, "%s", tmp);
1920 
1921 		/*
1922 		 * Include information about the associated SCSI target port.
1923 		 */
1924 		snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1925 			"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%llu\nPR_REG_END:"
1926 			" %d\n", tpg->se_tpg_tfo->fabric_name,
1927 			tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1928 			tpg->se_tpg_tfo->tpg_get_tag(tpg),
1929 			pr_reg->tg_pt_sep_rtpi, pr_reg->pr_aptpl_target_lun,
1930 			reg_count);
1931 
1932 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1933 			pr_err("Unable to update renaming APTPL metadata,"
1934 			       " reallocating larger buffer\n");
1935 			ret = -EMSGSIZE;
1936 			goto out;
1937 		}
1938 		len += sprintf(buf+len, "%s", tmp);
1939 		reg_count++;
1940 	}
1941 
1942 	if (!reg_count)
1943 		len += sprintf(buf+len, "No Registrations or Reservations");
1944 
1945 out:
1946 	spin_unlock(&dev->t10_pr.registration_lock);
1947 	spin_unlock(&dev->dev_reservation_lock);
1948 
1949 	return ret;
1950 }
1951 
1952 static int __core_scsi3_write_aptpl_to_file(
1953 	struct se_device *dev,
1954 	unsigned char *buf)
1955 {
1956 	struct t10_wwn *wwn = &dev->t10_wwn;
1957 	struct file *file;
1958 	int flags = O_RDWR | O_CREAT | O_TRUNC;
1959 	char *path;
1960 	u32 pr_aptpl_buf_len;
1961 	int ret;
1962 	loff_t pos = 0;
1963 
1964 	path = kasprintf(GFP_KERNEL, "%s/pr/aptpl_%s", db_root,
1965 			&wwn->unit_serial[0]);
1966 	if (!path)
1967 		return -ENOMEM;
1968 
1969 	file = filp_open(path, flags, 0600);
1970 	if (IS_ERR(file)) {
1971 		pr_err("filp_open(%s) for APTPL metadata"
1972 			" failed\n", path);
1973 		kfree(path);
1974 		return PTR_ERR(file);
1975 	}
1976 
1977 	pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
1978 
1979 	ret = kernel_write(file, buf, pr_aptpl_buf_len, &pos);
1980 
1981 	if (ret < 0)
1982 		pr_debug("Error writing APTPL metadata file: %s\n", path);
1983 	fput(file);
1984 	kfree(path);
1985 
1986 	return (ret < 0) ? -EIO : 0;
1987 }
1988 
1989 /*
1990  * Clear the APTPL metadata if APTPL has been disabled, otherwise
1991  * write out the updated metadata to struct file for this SCSI device.
1992  */
1993 static sense_reason_t core_scsi3_update_and_write_aptpl(struct se_device *dev, bool aptpl)
1994 {
1995 	unsigned char *buf;
1996 	int rc, len = PR_APTPL_BUF_LEN;
1997 
1998 	if (!aptpl) {
1999 		char *null_buf = "No Registrations or Reservations\n";
2000 
2001 		rc = __core_scsi3_write_aptpl_to_file(dev, null_buf);
2002 		dev->t10_pr.pr_aptpl_active = 0;
2003 		pr_debug("SPC-3 PR: Set APTPL Bit Deactivated\n");
2004 
2005 		if (rc)
2006 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2007 
2008 		return 0;
2009 	}
2010 retry:
2011 	buf = vzalloc(len);
2012 	if (!buf)
2013 		return TCM_OUT_OF_RESOURCES;
2014 
2015 	rc = core_scsi3_update_aptpl_buf(dev, buf, len);
2016 	if (rc < 0) {
2017 		vfree(buf);
2018 		len *= 2;
2019 		goto retry;
2020 	}
2021 
2022 	rc = __core_scsi3_write_aptpl_to_file(dev, buf);
2023 	if (rc != 0) {
2024 		pr_err("SPC-3 PR: Could not update APTPL\n");
2025 		vfree(buf);
2026 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2027 	}
2028 	dev->t10_pr.pr_aptpl_active = 1;
2029 	vfree(buf);
2030 	pr_debug("SPC-3 PR: Set APTPL Bit Activated\n");
2031 	return 0;
2032 }
2033 
2034 static sense_reason_t
2035 core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
2036 		bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type)
2037 {
2038 	struct se_session *se_sess = cmd->se_sess;
2039 	struct se_device *dev = cmd->se_dev;
2040 	struct se_lun *se_lun = cmd->se_lun;
2041 	struct se_portal_group *se_tpg;
2042 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp;
2043 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2044 	unsigned char isid_buf[PR_REG_ISID_LEN] = { };
2045 	unsigned char *isid_ptr = NULL;
2046 	sense_reason_t ret = TCM_NO_SENSE;
2047 	int pr_holder = 0, type;
2048 
2049 	if (!se_sess || !se_lun) {
2050 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2051 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2052 	}
2053 	se_tpg = se_sess->se_tpg;
2054 
2055 	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2056 		se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2057 				PR_REG_ISID_LEN);
2058 		isid_ptr = &isid_buf[0];
2059 	}
2060 	/*
2061 	 * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2062 	 */
2063 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2064 	if (!pr_reg) {
2065 		if (res_key) {
2066 			pr_warn("SPC-3 PR: Reservation Key non-zero"
2067 				" for SA REGISTER, returning CONFLICT\n");
2068 			return TCM_RESERVATION_CONFLICT;
2069 		}
2070 		/*
2071 		 * Do nothing but return GOOD status.
2072 		 */
2073 		if (!sa_res_key)
2074 			return 0;
2075 
2076 		if (!spec_i_pt) {
2077 			/*
2078 			 * Perform the Service Action REGISTER on the Initiator
2079 			 * Port Endpoint that the PRO was received from on the
2080 			 * Logical Unit of the SCSI device server.
2081 			 */
2082 			if (core_scsi3_alloc_registration(cmd->se_dev,
2083 					se_sess->se_node_acl, cmd->se_lun,
2084 					NULL, cmd->orig_fe_lun, isid_ptr,
2085 					sa_res_key, all_tg_pt, aptpl,
2086 					register_type, 0)) {
2087 				pr_err("Unable to allocate"
2088 					" struct t10_pr_registration\n");
2089 				return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
2090 			}
2091 		} else {
2092 			/*
2093 			 * Register both the Initiator port that received
2094 			 * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2095 			 * TransportID from Parameter list and loop through
2096 			 * fabric dependent parameter list while calling
2097 			 * logic from of core_scsi3_alloc_registration() for
2098 			 * each TransportID provided SCSI Initiator Port/Device
2099 			 */
2100 			ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2101 					isid_ptr, sa_res_key, all_tg_pt, aptpl);
2102 			if (ret != 0)
2103 				return ret;
2104 		}
2105 		return core_scsi3_update_and_write_aptpl(dev, aptpl);
2106 	}
2107 
2108 	/* ok, existing registration */
2109 
2110 	if ((register_type == REGISTER) && (res_key != pr_reg->pr_res_key)) {
2111 		pr_err("SPC-3 PR REGISTER: Received"
2112 		       " res_key: 0x%016Lx does not match"
2113 		       " existing SA REGISTER res_key:"
2114 		       " 0x%016Lx\n", res_key,
2115 		       pr_reg->pr_res_key);
2116 		ret = TCM_RESERVATION_CONFLICT;
2117 		goto out;
2118 	}
2119 
2120 	if (spec_i_pt) {
2121 		pr_err("SPC-3 PR REGISTER: SPEC_I_PT"
2122 			" set on a registered nexus\n");
2123 		ret = TCM_INVALID_PARAMETER_LIST;
2124 		goto out;
2125 	}
2126 
2127 	/*
2128 	 * An existing ALL_TG_PT=1 registration being released
2129 	 * must also set ALL_TG_PT=1 in the incoming PROUT.
2130 	 */
2131 	if (pr_reg->pr_reg_all_tg_pt && !all_tg_pt) {
2132 		pr_err("SPC-3 PR REGISTER: ALL_TG_PT=1"
2133 			" registration exists, but ALL_TG_PT=1 bit not"
2134 			" present in received PROUT\n");
2135 		ret = TCM_INVALID_CDB_FIELD;
2136 		goto out;
2137 	}
2138 
2139 	/*
2140 	 * sa_res_key=1 Change Reservation Key for registered I_T Nexus.
2141 	 */
2142 	if (sa_res_key) {
2143 		/*
2144 		 * Increment PRgeneration counter for struct se_device"
2145 		 * upon a successful REGISTER, see spc4r17 section 6.3.2
2146 		 * READ_KEYS service action.
2147 		 */
2148 		pr_reg->pr_res_generation = core_scsi3_pr_generation(cmd->se_dev);
2149 		pr_reg->pr_res_key = sa_res_key;
2150 		pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2151 			 " Key for %s to: 0x%016Lx PRgeneration:"
2152 			 " 0x%08x\n", cmd->se_tfo->fabric_name,
2153 			 (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ? "_AND_IGNORE_EXISTING_KEY" : "",
2154 			 pr_reg->pr_reg_nacl->initiatorname,
2155 			 pr_reg->pr_res_key, pr_reg->pr_res_generation);
2156 
2157 	} else {
2158 		/*
2159 		 * sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
2160 		 */
2161 		type = pr_reg->pr_res_type;
2162 		pr_holder = core_scsi3_check_implicit_release(cmd->se_dev,
2163 							      pr_reg);
2164 		if (pr_holder < 0) {
2165 			ret = TCM_RESERVATION_CONFLICT;
2166 			goto out;
2167 		}
2168 
2169 		spin_lock(&pr_tmpl->registration_lock);
2170 		/*
2171 		 * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2172 		 * and matching pr_res_key.
2173 		 */
2174 		if (pr_reg->pr_reg_all_tg_pt) {
2175 			list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2176 					&pr_tmpl->registration_list,
2177 					pr_reg_list) {
2178 
2179 				if (!pr_reg_p->pr_reg_all_tg_pt)
2180 					continue;
2181 				if (pr_reg_p->pr_res_key != res_key)
2182 					continue;
2183 				if (pr_reg == pr_reg_p)
2184 					continue;
2185 				if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2186 					   pr_reg_p->pr_reg_nacl->initiatorname))
2187 					continue;
2188 
2189 				__core_scsi3_free_registration(dev,
2190 						pr_reg_p, NULL, 0);
2191 			}
2192 		}
2193 
2194 		/*
2195 		 * Release the calling I_T Nexus registration now..
2196 		 */
2197 		__core_scsi3_free_registration(cmd->se_dev, pr_reg, NULL, 1);
2198 		pr_reg = NULL;
2199 
2200 		/*
2201 		 * From spc4r17, section 5.7.11.3 Unregistering
2202 		 *
2203 		 * If the persistent reservation is a registrants only
2204 		 * type, the device server shall establish a unit
2205 		 * attention condition for the initiator port associated
2206 		 * with every registered I_T nexus except for the I_T
2207 		 * nexus on which the PERSISTENT RESERVE OUT command was
2208 		 * received, with the additional sense code set to
2209 		 * RESERVATIONS RELEASED.
2210 		 */
2211 		if (pr_holder &&
2212 		    (type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY ||
2213 		     type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY)) {
2214 			list_for_each_entry(pr_reg_p,
2215 					&pr_tmpl->registration_list,
2216 					pr_reg_list) {
2217 
2218 				target_ua_allocate_lun(
2219 					pr_reg_p->pr_reg_nacl,
2220 					pr_reg_p->pr_res_mapped_lun,
2221 					0x2A,
2222 					ASCQ_2AH_RESERVATIONS_RELEASED);
2223 			}
2224 		}
2225 
2226 		spin_unlock(&pr_tmpl->registration_lock);
2227 	}
2228 
2229 	ret = core_scsi3_update_and_write_aptpl(dev, aptpl);
2230 
2231 out:
2232 	if (pr_reg)
2233 		core_scsi3_put_pr_reg(pr_reg);
2234 	return ret;
2235 }
2236 
2237 unsigned char *core_scsi3_pr_dump_type(int type)
2238 {
2239 	switch (type) {
2240 	case PR_TYPE_WRITE_EXCLUSIVE:
2241 		return "Write Exclusive Access";
2242 	case PR_TYPE_EXCLUSIVE_ACCESS:
2243 		return "Exclusive Access";
2244 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2245 		return "Write Exclusive Access, Registrants Only";
2246 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2247 		return "Exclusive Access, Registrants Only";
2248 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2249 		return "Write Exclusive Access, All Registrants";
2250 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2251 		return "Exclusive Access, All Registrants";
2252 	default:
2253 		break;
2254 	}
2255 
2256 	return "Unknown SPC-3 PR Type";
2257 }
2258 
2259 static sense_reason_t
2260 core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
2261 {
2262 	struct se_device *dev = cmd->se_dev;
2263 	struct se_session *se_sess = cmd->se_sess;
2264 	struct se_lun *se_lun = cmd->se_lun;
2265 	struct t10_pr_registration *pr_reg, *pr_res_holder;
2266 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2267 	char i_buf[PR_REG_ISID_ID_LEN] = { };
2268 	sense_reason_t ret;
2269 
2270 	if (!se_sess || !se_lun) {
2271 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2272 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2273 	}
2274 	/*
2275 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2276 	 */
2277 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2278 				se_sess);
2279 	if (!pr_reg) {
2280 		pr_err("SPC-3 PR: Unable to locate"
2281 			" PR_REGISTERED *pr_reg for RESERVE\n");
2282 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2283 	}
2284 	/*
2285 	 * From spc4r17 Section 5.7.9: Reserving:
2286 	 *
2287 	 * An application client creates a persistent reservation by issuing
2288 	 * a PERSISTENT RESERVE OUT command with RESERVE service action through
2289 	 * a registered I_T nexus with the following parameters:
2290 	 *    a) RESERVATION KEY set to the value of the reservation key that is
2291 	 * 	 registered with the logical unit for the I_T nexus; and
2292 	 */
2293 	if (res_key != pr_reg->pr_res_key) {
2294 		pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2295 			" does not match existing SA REGISTER res_key:"
2296 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2297 		ret = TCM_RESERVATION_CONFLICT;
2298 		goto out_put_pr_reg;
2299 	}
2300 	/*
2301 	 * From spc4r17 Section 5.7.9: Reserving:
2302 	 *
2303 	 * From above:
2304 	 *  b) TYPE field and SCOPE field set to the persistent reservation
2305 	 *     being created.
2306 	 *
2307 	 * Only one persistent reservation is allowed at a time per logical unit
2308 	 * and that persistent reservation has a scope of LU_SCOPE.
2309 	 */
2310 	if (scope != PR_SCOPE_LU_SCOPE) {
2311 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2312 		ret = TCM_INVALID_PARAMETER_LIST;
2313 		goto out_put_pr_reg;
2314 	}
2315 	/*
2316 	 * See if we have an existing PR reservation holder pointer at
2317 	 * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2318 	 * *pr_res_holder.
2319 	 */
2320 	spin_lock(&dev->dev_reservation_lock);
2321 	pr_res_holder = dev->dev_pr_res_holder;
2322 	if (pr_res_holder) {
2323 		/*
2324 		 * From spc4r17 Section 5.7.9: Reserving:
2325 		 *
2326 		 * If the device server receives a PERSISTENT RESERVE OUT
2327 		 * command from an I_T nexus other than a persistent reservation
2328 		 * holder (see 5.7.10) that attempts to create a persistent
2329 		 * reservation when a persistent reservation already exists for
2330 		 * the logical unit, then the command shall be completed with
2331 		 * RESERVATION CONFLICT status.
2332 		 */
2333 		if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2334 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2335 			pr_err("SPC-3 PR: Attempted RESERVE from"
2336 				" [%s]: %s while reservation already held by"
2337 				" [%s]: %s, returning RESERVATION_CONFLICT\n",
2338 				cmd->se_tfo->fabric_name,
2339 				se_sess->se_node_acl->initiatorname,
2340 				pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2341 				pr_res_holder->pr_reg_nacl->initiatorname);
2342 
2343 			spin_unlock(&dev->dev_reservation_lock);
2344 			ret = TCM_RESERVATION_CONFLICT;
2345 			goto out_put_pr_reg;
2346 		}
2347 		/*
2348 		 * From spc4r17 Section 5.7.9: Reserving:
2349 		 *
2350 		 * If a persistent reservation holder attempts to modify the
2351 		 * type or scope of an existing persistent reservation, the
2352 		 * command shall be completed with RESERVATION CONFLICT status.
2353 		 */
2354 		if ((pr_res_holder->pr_res_type != type) ||
2355 		    (pr_res_holder->pr_res_scope != scope)) {
2356 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2357 			pr_err("SPC-3 PR: Attempted RESERVE from"
2358 				" [%s]: %s trying to change TYPE and/or SCOPE,"
2359 				" while reservation already held by [%s]: %s,"
2360 				" returning RESERVATION_CONFLICT\n",
2361 				cmd->se_tfo->fabric_name,
2362 				se_sess->se_node_acl->initiatorname,
2363 				pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2364 				pr_res_holder->pr_reg_nacl->initiatorname);
2365 
2366 			spin_unlock(&dev->dev_reservation_lock);
2367 			ret = TCM_RESERVATION_CONFLICT;
2368 			goto out_put_pr_reg;
2369 		}
2370 		/*
2371 		 * From spc4r17 Section 5.7.9: Reserving:
2372 		 *
2373 		 * If the device server receives a PERSISTENT RESERVE OUT
2374 		 * command with RESERVE service action where the TYPE field and
2375 		 * the SCOPE field contain the same values as the existing type
2376 		 * and scope from a persistent reservation holder, it shall not
2377 		 * make any change to the existing persistent reservation and
2378 		 * shall completethe command with GOOD status.
2379 		 */
2380 		spin_unlock(&dev->dev_reservation_lock);
2381 		ret = 0;
2382 		goto out_put_pr_reg;
2383 	}
2384 	/*
2385 	 * Otherwise, our *pr_reg becomes the PR reservation holder for said
2386 	 * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2387 	 */
2388 	pr_reg->pr_res_scope = scope;
2389 	pr_reg->pr_res_type = type;
2390 	pr_reg->pr_res_holder = 1;
2391 	dev->dev_pr_res_holder = pr_reg;
2392 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2393 
2394 	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2395 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2396 		cmd->se_tfo->fabric_name, core_scsi3_pr_dump_type(type),
2397 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2398 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2399 			cmd->se_tfo->fabric_name,
2400 			se_sess->se_node_acl->initiatorname,
2401 			i_buf);
2402 	spin_unlock(&dev->dev_reservation_lock);
2403 
2404 	if (pr_tmpl->pr_aptpl_active)
2405 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2406 
2407 	ret = 0;
2408 out_put_pr_reg:
2409 	core_scsi3_put_pr_reg(pr_reg);
2410 	return ret;
2411 }
2412 
2413 static sense_reason_t
2414 core_scsi3_emulate_pro_reserve(struct se_cmd *cmd, int type, int scope,
2415 		u64 res_key)
2416 {
2417 	switch (type) {
2418 	case PR_TYPE_WRITE_EXCLUSIVE:
2419 	case PR_TYPE_EXCLUSIVE_ACCESS:
2420 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2421 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2422 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2423 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2424 		return core_scsi3_pro_reserve(cmd, type, scope, res_key);
2425 	default:
2426 		pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2427 			" 0x%02x\n", type);
2428 		return TCM_INVALID_CDB_FIELD;
2429 	}
2430 }
2431 
2432 static void __core_scsi3_complete_pro_release(
2433 	struct se_device *dev,
2434 	struct se_node_acl *se_nacl,
2435 	struct t10_pr_registration *pr_reg,
2436 	int explicit,
2437 	int unreg)
2438 {
2439 	const struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2440 	char i_buf[PR_REG_ISID_ID_LEN] = { };
2441 	int pr_res_type = 0, pr_res_scope = 0;
2442 
2443 	lockdep_assert_held(&dev->dev_reservation_lock);
2444 
2445 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2446 	/*
2447 	 * Go ahead and release the current PR reservation holder.
2448 	 * If an All Registrants reservation is currently active and
2449 	 * a unregister operation is requested, replace the current
2450 	 * dev_pr_res_holder with another active registration.
2451 	 */
2452 	if (dev->dev_pr_res_holder) {
2453 		pr_res_type = dev->dev_pr_res_holder->pr_res_type;
2454 		pr_res_scope = dev->dev_pr_res_holder->pr_res_scope;
2455 		dev->dev_pr_res_holder->pr_res_type = 0;
2456 		dev->dev_pr_res_holder->pr_res_scope = 0;
2457 		dev->dev_pr_res_holder->pr_res_holder = 0;
2458 		dev->dev_pr_res_holder = NULL;
2459 	}
2460 	if (!unreg)
2461 		goto out;
2462 
2463 	spin_lock(&dev->t10_pr.registration_lock);
2464 	list_del_init(&pr_reg->pr_reg_list);
2465 	/*
2466 	 * If the I_T nexus is a reservation holder, the persistent reservation
2467 	 * is of an all registrants type, and the I_T nexus is the last remaining
2468 	 * registered I_T nexus, then the device server shall also release the
2469 	 * persistent reservation.
2470 	 */
2471 	if (!list_empty(&dev->t10_pr.registration_list) &&
2472 	    ((pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2473 	     (pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))) {
2474 		dev->dev_pr_res_holder =
2475 			list_entry(dev->t10_pr.registration_list.next,
2476 				   struct t10_pr_registration, pr_reg_list);
2477 		dev->dev_pr_res_holder->pr_res_type = pr_res_type;
2478 		dev->dev_pr_res_holder->pr_res_scope = pr_res_scope;
2479 		dev->dev_pr_res_holder->pr_res_holder = 1;
2480 	}
2481 	spin_unlock(&dev->t10_pr.registration_lock);
2482 out:
2483 	if (!dev->dev_pr_res_holder) {
2484 		pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2485 			" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2486 			tfo->fabric_name, (explicit) ? "explicit" :
2487 			"implicit", core_scsi3_pr_dump_type(pr_res_type),
2488 			(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2489 	}
2490 	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2491 		tfo->fabric_name, se_nacl->initiatorname,
2492 		i_buf);
2493 	/*
2494 	 * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2495 	 */
2496 	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2497 }
2498 
2499 static sense_reason_t
2500 core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
2501 		u64 res_key)
2502 {
2503 	struct se_device *dev = cmd->se_dev;
2504 	struct se_session *se_sess = cmd->se_sess;
2505 	struct se_lun *se_lun = cmd->se_lun;
2506 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2507 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2508 	sense_reason_t ret = 0;
2509 
2510 	if (!se_sess || !se_lun) {
2511 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2512 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2513 	}
2514 	/*
2515 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2516 	 */
2517 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2518 	if (!pr_reg) {
2519 		pr_err("SPC-3 PR: Unable to locate"
2520 			" PR_REGISTERED *pr_reg for RELEASE\n");
2521 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2522 	}
2523 	/*
2524 	 * From spc4r17 Section 5.7.11.2 Releasing:
2525 	 *
2526 	 * If there is no persistent reservation or in response to a persistent
2527 	 * reservation release request from a registered I_T nexus that is not a
2528 	 * persistent reservation holder (see 5.7.10), the device server shall
2529 	 * do the following:
2530 	 *
2531 	 *     a) Not release the persistent reservation, if any;
2532 	 *     b) Not remove any registrations; and
2533 	 *     c) Complete the command with GOOD status.
2534 	 */
2535 	spin_lock(&dev->dev_reservation_lock);
2536 	pr_res_holder = dev->dev_pr_res_holder;
2537 	if (!pr_res_holder) {
2538 		/*
2539 		 * No persistent reservation, return GOOD status.
2540 		 */
2541 		spin_unlock(&dev->dev_reservation_lock);
2542 		goto out_put_pr_reg;
2543 	}
2544 
2545 	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2546 		/*
2547 		 * Release request from a registered I_T nexus that is not a
2548 		 * persistent reservation holder. return GOOD status.
2549 		 */
2550 		spin_unlock(&dev->dev_reservation_lock);
2551 		goto out_put_pr_reg;
2552 	}
2553 
2554 	/*
2555 	 * From spc4r17 Section 5.7.11.2 Releasing:
2556 	 *
2557 	 * Only the persistent reservation holder (see 5.7.10) is allowed to
2558 	 * release a persistent reservation.
2559 	 *
2560 	 * An application client releases the persistent reservation by issuing
2561 	 * a PERSISTENT RESERVE OUT command with RELEASE service action through
2562 	 * an I_T nexus that is a persistent reservation holder with the
2563 	 * following parameters:
2564 	 *
2565 	 *     a) RESERVATION KEY field set to the value of the reservation key
2566 	 *	  that is registered with the logical unit for the I_T nexus;
2567 	 */
2568 	if (res_key != pr_reg->pr_res_key) {
2569 		pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2570 			" does not match existing SA REGISTER res_key:"
2571 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2572 		spin_unlock(&dev->dev_reservation_lock);
2573 		ret = TCM_RESERVATION_CONFLICT;
2574 		goto out_put_pr_reg;
2575 	}
2576 	/*
2577 	 * From spc4r17 Section 5.7.11.2 Releasing and above:
2578 	 *
2579 	 * b) TYPE field and SCOPE field set to match the persistent
2580 	 *    reservation being released.
2581 	 */
2582 	if ((pr_res_holder->pr_res_type != type) ||
2583 	    (pr_res_holder->pr_res_scope != scope)) {
2584 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2585 		pr_err("SPC-3 PR RELEASE: Attempted to release"
2586 			" reservation from [%s]: %s with different TYPE "
2587 			"and/or SCOPE  while reservation already held by"
2588 			" [%s]: %s, returning RESERVATION_CONFLICT\n",
2589 			cmd->se_tfo->fabric_name,
2590 			se_sess->se_node_acl->initiatorname,
2591 			pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2592 			pr_res_holder->pr_reg_nacl->initiatorname);
2593 
2594 		spin_unlock(&dev->dev_reservation_lock);
2595 		ret = TCM_RESERVATION_CONFLICT;
2596 		goto out_put_pr_reg;
2597 	}
2598 	/*
2599 	 * In response to a persistent reservation release request from the
2600 	 * persistent reservation holder the device server shall perform a
2601 	 * release by doing the following as an uninterrupted series of actions:
2602 	 * a) Release the persistent reservation;
2603 	 * b) Not remove any registration(s);
2604 	 * c) If the released persistent reservation is a registrants only type
2605 	 * or all registrants type persistent reservation,
2606 	 *    the device server shall establish a unit attention condition for
2607 	 *    the initiator port associated with every regis-
2608 	 *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2609 	 *    RESERVE OUT command with RELEASE service action was received,
2610 	 *    with the additional sense code set to RESERVATIONS RELEASED; and
2611 	 * d) If the persistent reservation is of any other type, the device
2612 	 *    server shall not establish a unit attention condition.
2613 	 */
2614 	__core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2615 					  pr_reg, 1, 0);
2616 
2617 	spin_unlock(&dev->dev_reservation_lock);
2618 
2619 	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2620 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2621 	    (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2622 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2623 		/*
2624 		 * If no UNIT ATTENTION conditions will be established for
2625 		 * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2626 		 * go ahead and check for APTPL=1 update+write below
2627 		 */
2628 		goto write_aptpl;
2629 	}
2630 
2631 	spin_lock(&pr_tmpl->registration_lock);
2632 	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2633 			pr_reg_list) {
2634 		/*
2635 		 * Do not establish a UNIT ATTENTION condition
2636 		 * for the calling I_T Nexus
2637 		 */
2638 		if (pr_reg_p == pr_reg)
2639 			continue;
2640 
2641 		target_ua_allocate_lun(pr_reg_p->pr_reg_nacl,
2642 				pr_reg_p->pr_res_mapped_lun,
2643 				0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2644 	}
2645 	spin_unlock(&pr_tmpl->registration_lock);
2646 
2647 write_aptpl:
2648 	if (pr_tmpl->pr_aptpl_active)
2649 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2650 
2651 out_put_pr_reg:
2652 	core_scsi3_put_pr_reg(pr_reg);
2653 	return ret;
2654 }
2655 
2656 static sense_reason_t
2657 core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
2658 {
2659 	struct se_device *dev = cmd->se_dev;
2660 	struct se_node_acl *pr_reg_nacl;
2661 	struct se_session *se_sess = cmd->se_sess;
2662 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2663 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2664 	u64 pr_res_mapped_lun = 0;
2665 	int calling_it_nexus = 0;
2666 	/*
2667 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2668 	 */
2669 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2670 			se_sess->se_node_acl, se_sess);
2671 	if (!pr_reg_n) {
2672 		pr_err("SPC-3 PR: Unable to locate"
2673 			" PR_REGISTERED *pr_reg for CLEAR\n");
2674 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2675 	}
2676 	/*
2677 	 * From spc4r17 section 5.7.11.6, Clearing:
2678 	 *
2679 	 * Any application client may release the persistent reservation and
2680 	 * remove all registrations from a device server by issuing a
2681 	 * PERSISTENT RESERVE OUT command with CLEAR service action through a
2682 	 * registered I_T nexus with the following parameter:
2683 	 *
2684 	 *	a) RESERVATION KEY field set to the value of the reservation key
2685 	 * 	   that is registered with the logical unit for the I_T nexus.
2686 	 */
2687 	if (res_key != pr_reg_n->pr_res_key) {
2688 		pr_err("SPC-3 PR REGISTER: Received"
2689 			" res_key: 0x%016Lx does not match"
2690 			" existing SA REGISTER res_key:"
2691 			" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2692 		core_scsi3_put_pr_reg(pr_reg_n);
2693 		return TCM_RESERVATION_CONFLICT;
2694 	}
2695 	/*
2696 	 * a) Release the persistent reservation, if any;
2697 	 */
2698 	spin_lock(&dev->dev_reservation_lock);
2699 	pr_res_holder = dev->dev_pr_res_holder;
2700 	if (pr_res_holder) {
2701 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2702 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
2703 						  pr_res_holder, 0, 0);
2704 	}
2705 	spin_unlock(&dev->dev_reservation_lock);
2706 	/*
2707 	 * b) Remove all registration(s) (see spc4r17 5.7.7);
2708 	 */
2709 	spin_lock(&pr_tmpl->registration_lock);
2710 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2711 			&pr_tmpl->registration_list, pr_reg_list) {
2712 
2713 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2714 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2715 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2716 		__core_scsi3_free_registration(dev, pr_reg, NULL,
2717 					calling_it_nexus);
2718 		/*
2719 		 * e) Establish a unit attention condition for the initiator
2720 		 *    port associated with every registered I_T nexus other
2721 		 *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2722 		 *    command with CLEAR service action was received, with the
2723 		 *    additional sense code set to RESERVATIONS PREEMPTED.
2724 		 */
2725 		if (!calling_it_nexus)
2726 			target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun,
2727 				0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2728 	}
2729 	spin_unlock(&pr_tmpl->registration_lock);
2730 
2731 	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2732 		cmd->se_tfo->fabric_name);
2733 
2734 	core_scsi3_update_and_write_aptpl(cmd->se_dev, false);
2735 
2736 	core_scsi3_pr_generation(dev);
2737 	return 0;
2738 }
2739 
2740 static void __core_scsi3_complete_pro_preempt(
2741 	struct se_device *dev,
2742 	struct t10_pr_registration *pr_reg,
2743 	struct list_head *preempt_and_abort_list,
2744 	int type,
2745 	int scope,
2746 	enum preempt_type preempt_type)
2747 {
2748 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2749 	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2750 	char i_buf[PR_REG_ISID_ID_LEN] = { };
2751 
2752 	lockdep_assert_held(&dev->dev_reservation_lock);
2753 
2754 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2755 	/*
2756 	 * Do an implicit RELEASE of the existing reservation.
2757 	 */
2758 	if (dev->dev_pr_res_holder)
2759 		__core_scsi3_complete_pro_release(dev, nacl,
2760 						  dev->dev_pr_res_holder, 0, 0);
2761 
2762 	dev->dev_pr_res_holder = pr_reg;
2763 	pr_reg->pr_res_holder = 1;
2764 	pr_reg->pr_res_type = type;
2765 	pr_reg->pr_res_scope = scope;
2766 
2767 	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2768 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2769 		tfo->fabric_name, (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2770 		core_scsi3_pr_dump_type(type),
2771 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2772 	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2773 		tfo->fabric_name, (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2774 		nacl->initiatorname, i_buf);
2775 	/*
2776 	 * For PREEMPT_AND_ABORT, add the preempting reservation's
2777 	 * struct t10_pr_registration to the list that will be compared
2778 	 * against received CDBs..
2779 	 */
2780 	if (preempt_and_abort_list)
2781 		list_add_tail(&pr_reg->pr_reg_abort_list,
2782 				preempt_and_abort_list);
2783 }
2784 
2785 static void core_scsi3_release_preempt_and_abort(
2786 	struct list_head *preempt_and_abort_list,
2787 	struct t10_pr_registration *pr_reg_holder)
2788 {
2789 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2790 
2791 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2792 				pr_reg_abort_list) {
2793 
2794 		list_del(&pr_reg->pr_reg_abort_list);
2795 		if (pr_reg_holder == pr_reg)
2796 			continue;
2797 		if (pr_reg->pr_res_holder) {
2798 			pr_warn("pr_reg->pr_res_holder still set\n");
2799 			continue;
2800 		}
2801 
2802 		pr_reg->pr_reg_deve = NULL;
2803 		pr_reg->pr_reg_nacl = NULL;
2804 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
2805 	}
2806 }
2807 
2808 static sense_reason_t
2809 core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
2810 		u64 sa_res_key, enum preempt_type preempt_type)
2811 {
2812 	struct se_device *dev = cmd->se_dev;
2813 	struct se_node_acl *pr_reg_nacl;
2814 	struct se_session *se_sess = cmd->se_sess;
2815 	LIST_HEAD(preempt_and_abort_list);
2816 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2817 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2818 	u64 pr_res_mapped_lun = 0;
2819 	int all_reg = 0, calling_it_nexus = 0;
2820 	bool sa_res_key_unmatched = sa_res_key != 0;
2821 	int prh_type = 0, prh_scope = 0;
2822 
2823 	if (!se_sess)
2824 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2825 
2826 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2827 				se_sess);
2828 	if (!pr_reg_n) {
2829 		pr_err("SPC-3 PR: Unable to locate"
2830 			" PR_REGISTERED *pr_reg for PREEMPT%s\n",
2831 			(preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "");
2832 		return TCM_RESERVATION_CONFLICT;
2833 	}
2834 	if (pr_reg_n->pr_res_key != res_key) {
2835 		core_scsi3_put_pr_reg(pr_reg_n);
2836 		return TCM_RESERVATION_CONFLICT;
2837 	}
2838 	if (scope != PR_SCOPE_LU_SCOPE) {
2839 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2840 		core_scsi3_put_pr_reg(pr_reg_n);
2841 		return TCM_INVALID_PARAMETER_LIST;
2842 	}
2843 
2844 	spin_lock(&dev->dev_reservation_lock);
2845 	pr_res_holder = dev->dev_pr_res_holder;
2846 	if (pr_res_holder &&
2847 	   ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2848 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
2849 		all_reg = 1;
2850 
2851 	if (!all_reg && !sa_res_key) {
2852 		spin_unlock(&dev->dev_reservation_lock);
2853 		core_scsi3_put_pr_reg(pr_reg_n);
2854 		return TCM_INVALID_PARAMETER_LIST;
2855 	}
2856 	/*
2857 	 * From spc4r17, section 5.7.11.4.4 Removing Registrations:
2858 	 *
2859 	 * If the SERVICE ACTION RESERVATION KEY field does not identify a
2860 	 * persistent reservation holder or there is no persistent reservation
2861 	 * holder (i.e., there is no persistent reservation), then the device
2862 	 * server shall perform a preempt by doing the following in an
2863 	 * uninterrupted series of actions. (See below..)
2864 	 */
2865 	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
2866 		/*
2867 		 * No existing or SA Reservation Key matching reservations..
2868 		 *
2869 		 * PROUT SA PREEMPT with All Registrant type reservations are
2870 		 * allowed to be processed without a matching SA Reservation Key
2871 		 */
2872 		spin_lock(&pr_tmpl->registration_lock);
2873 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2874 				&pr_tmpl->registration_list, pr_reg_list) {
2875 			/*
2876 			 * Removing of registrations in non all registrants
2877 			 * type reservations without a matching SA reservation
2878 			 * key.
2879 			 *
2880 			 * a) Remove the registrations for all I_T nexuses
2881 			 *    specified by the SERVICE ACTION RESERVATION KEY
2882 			 *    field;
2883 			 * b) Ignore the contents of the SCOPE and TYPE fields;
2884 			 * c) Process tasks as defined in 5.7.1; and
2885 			 * d) Establish a unit attention condition for the
2886 			 *    initiator port associated with every I_T nexus
2887 			 *    that lost its registration other than the I_T
2888 			 *    nexus on which the PERSISTENT RESERVE OUT command
2889 			 *    was received, with the additional sense code set
2890 			 *    to REGISTRATIONS PREEMPTED.
2891 			 */
2892 			if (!all_reg) {
2893 				if (pr_reg->pr_res_key != sa_res_key)
2894 					continue;
2895 				sa_res_key_unmatched = false;
2896 
2897 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2898 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2899 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2900 				__core_scsi3_free_registration(dev, pr_reg,
2901 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2902 						NULL, calling_it_nexus);
2903 			} else {
2904 				/*
2905 				 * Case for any existing all registrants type
2906 				 * reservation, follow logic in spc4r17 section
2907 				 * 5.7.11.4 Preempting, Table 52 and Figure 7.
2908 				 *
2909 				 * For a ZERO SA Reservation key, release
2910 				 * all other registrations and do an implicit
2911 				 * release of active persistent reservation.
2912 				 *
2913 				 * For a non-ZERO SA Reservation key, only
2914 				 * release the matching reservation key from
2915 				 * registrations.
2916 				 */
2917 				if ((sa_res_key) &&
2918 				     (pr_reg->pr_res_key != sa_res_key))
2919 					continue;
2920 				sa_res_key_unmatched = false;
2921 
2922 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2923 				if (calling_it_nexus)
2924 					continue;
2925 
2926 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2927 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2928 				__core_scsi3_free_registration(dev, pr_reg,
2929 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2930 						NULL, 0);
2931 			}
2932 			if (!calling_it_nexus)
2933 				target_ua_allocate_lun(pr_reg_nacl,
2934 					pr_res_mapped_lun, 0x2A,
2935 					ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2936 		}
2937 		spin_unlock(&pr_tmpl->registration_lock);
2938 		/*
2939 		 * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
2940 		 * a PREEMPT AND ABORT service action sets the SERVICE ACTION
2941 		 * RESERVATION KEY field to a value that does not match any
2942 		 * registered reservation key, then the device server shall
2943 		 * complete the command with RESERVATION CONFLICT status.
2944 		 */
2945 		if (sa_res_key_unmatched) {
2946 			spin_unlock(&dev->dev_reservation_lock);
2947 			core_scsi3_put_pr_reg(pr_reg_n);
2948 			return TCM_RESERVATION_CONFLICT;
2949 		}
2950 		/*
2951 		 * For an existing all registrants type reservation
2952 		 * with a zero SA rservation key, preempt the existing
2953 		 * reservation with the new PR type and scope.
2954 		 */
2955 		if (pr_res_holder && all_reg && !(sa_res_key)) {
2956 			__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
2957 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2958 				type, scope, preempt_type);
2959 		}
2960 
2961 		spin_unlock(&dev->dev_reservation_lock);
2962 
2963 		/*
2964 		 * SPC-4 5.12.11.2.6 Preempting and aborting
2965 		 * The actions described in this subclause shall be performed
2966 		 * for all I_T nexuses that are registered with the non-zero
2967 		 * SERVICE ACTION RESERVATION KEY value, without regard for
2968 		 * whether the preempted I_T nexuses hold the persistent
2969 		 * reservation. If the SERVICE ACTION RESERVATION KEY field is
2970 		 * set to zero and an all registrants persistent reservation is
2971 		 * present, the device server shall abort all commands for all
2972 		 * registered I_T nexuses.
2973 		 */
2974 		if (preempt_type == PREEMPT_AND_ABORT) {
2975 			core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list,
2976 					   cmd);
2977 			core_scsi3_release_preempt_and_abort(
2978 				&preempt_and_abort_list, pr_reg_n);
2979 		}
2980 
2981 		if (pr_tmpl->pr_aptpl_active)
2982 			core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2983 
2984 		core_scsi3_put_pr_reg(pr_reg_n);
2985 		core_scsi3_pr_generation(cmd->se_dev);
2986 		return 0;
2987 	}
2988 	/*
2989 	 * The PREEMPTing SA reservation key matches that of the
2990 	 * existing persistent reservation, first, we check if
2991 	 * we are preempting our own reservation.
2992 	 * From spc4r17, section 5.7.11.4.3 Preempting
2993 	 * persistent reservations and registration handling
2994 	 *
2995 	 * If an all registrants persistent reservation is not
2996 	 * present, it is not an error for the persistent
2997 	 * reservation holder to preempt itself (i.e., a
2998 	 * PERSISTENT RESERVE OUT with a PREEMPT service action
2999 	 * or a PREEMPT AND ABORT service action with the
3000 	 * SERVICE ACTION RESERVATION KEY value equal to the
3001 	 * persistent reservation holder's reservation key that
3002 	 * is received from the persistent reservation holder).
3003 	 * In that case, the device server shall establish the
3004 	 * new persistent reservation and maintain the
3005 	 * registration.
3006 	 */
3007 	prh_type = pr_res_holder->pr_res_type;
3008 	prh_scope = pr_res_holder->pr_res_scope;
3009 	/*
3010 	 * If the SERVICE ACTION RESERVATION KEY field identifies a
3011 	 * persistent reservation holder (see 5.7.10), the device
3012 	 * server shall perform a preempt by doing the following as
3013 	 * an uninterrupted series of actions:
3014 	 *
3015 	 * a) Release the persistent reservation for the holder
3016 	 *    identified by the SERVICE ACTION RESERVATION KEY field;
3017 	 */
3018 	if (pr_reg_n != pr_res_holder)
3019 		__core_scsi3_complete_pro_release(dev,
3020 						  pr_res_holder->pr_reg_nacl,
3021 						  dev->dev_pr_res_holder, 0, 0);
3022 	/*
3023 	 * b) Remove the registrations for all I_T nexuses identified
3024 	 *    by the SERVICE ACTION RESERVATION KEY field, except the
3025 	 *    I_T nexus that is being used for the PERSISTENT RESERVE
3026 	 *    OUT command. If an all registrants persistent reservation
3027 	 *    is present and the SERVICE ACTION RESERVATION KEY field
3028 	 *    is set to zero, then all registrations shall be removed
3029 	 *    except for that of the I_T nexus that is being used for
3030 	 *    the PERSISTENT RESERVE OUT command;
3031 	 */
3032 	spin_lock(&pr_tmpl->registration_lock);
3033 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3034 			&pr_tmpl->registration_list, pr_reg_list) {
3035 
3036 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3037 		if (calling_it_nexus)
3038 			continue;
3039 
3040 		if (sa_res_key && pr_reg->pr_res_key != sa_res_key)
3041 			continue;
3042 
3043 		pr_reg_nacl = pr_reg->pr_reg_nacl;
3044 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3045 		__core_scsi3_free_registration(dev, pr_reg,
3046 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3047 				calling_it_nexus);
3048 		/*
3049 		 * e) Establish a unit attention condition for the initiator
3050 		 *    port associated with every I_T nexus that lost its
3051 		 *    persistent reservation and/or registration, with the
3052 		 *    additional sense code set to REGISTRATIONS PREEMPTED;
3053 		 */
3054 		target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3055 				ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3056 	}
3057 	spin_unlock(&pr_tmpl->registration_lock);
3058 	/*
3059 	 * c) Establish a persistent reservation for the preempting
3060 	 *    I_T nexus using the contents of the SCOPE and TYPE fields;
3061 	 */
3062 	__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3063 			(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3064 			type, scope, preempt_type);
3065 	/*
3066 	 * d) Process tasks as defined in 5.7.1;
3067 	 * e) See above..
3068 	 * f) If the type or scope has changed, then for every I_T nexus
3069 	 *    whose reservation key was not removed, except for the I_T
3070 	 *    nexus on which the PERSISTENT RESERVE OUT command was
3071 	 *    received, the device server shall establish a unit
3072 	 *    attention condition for the initiator port associated with
3073 	 *    that I_T nexus, with the additional sense code set to
3074 	 *    RESERVATIONS RELEASED. If the type or scope have not
3075 	 *    changed, then no unit attention condition(s) shall be
3076 	 *    established for this reason.
3077 	 */
3078 	if ((prh_type != type) || (prh_scope != scope)) {
3079 		spin_lock(&pr_tmpl->registration_lock);
3080 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3081 				&pr_tmpl->registration_list, pr_reg_list) {
3082 
3083 			calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3084 			if (calling_it_nexus)
3085 				continue;
3086 
3087 			target_ua_allocate_lun(pr_reg->pr_reg_nacl,
3088 					pr_reg->pr_res_mapped_lun, 0x2A,
3089 					ASCQ_2AH_RESERVATIONS_RELEASED);
3090 		}
3091 		spin_unlock(&pr_tmpl->registration_lock);
3092 	}
3093 	spin_unlock(&dev->dev_reservation_lock);
3094 	/*
3095 	 * Call LUN_RESET logic upon list of struct t10_pr_registration,
3096 	 * All received CDBs for the matching existing reservation and
3097 	 * registrations undergo ABORT_TASK logic.
3098 	 *
3099 	 * From there, core_scsi3_release_preempt_and_abort() will
3100 	 * release every registration in the list (which have already
3101 	 * been removed from the primary pr_reg list), except the
3102 	 * new persistent reservation holder, the calling Initiator Port.
3103 	 */
3104 	if (preempt_type == PREEMPT_AND_ABORT) {
3105 		core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3106 		core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3107 						pr_reg_n);
3108 	}
3109 
3110 	if (pr_tmpl->pr_aptpl_active)
3111 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
3112 
3113 	core_scsi3_put_pr_reg(pr_reg_n);
3114 	core_scsi3_pr_generation(cmd->se_dev);
3115 	return 0;
3116 }
3117 
3118 static sense_reason_t
3119 core_scsi3_emulate_pro_preempt(struct se_cmd *cmd, int type, int scope,
3120 		u64 res_key, u64 sa_res_key, enum preempt_type preempt_type)
3121 {
3122 	switch (type) {
3123 	case PR_TYPE_WRITE_EXCLUSIVE:
3124 	case PR_TYPE_EXCLUSIVE_ACCESS:
3125 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3126 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3127 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3128 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3129 		return core_scsi3_pro_preempt(cmd, type, scope, res_key,
3130 					      sa_res_key, preempt_type);
3131 	default:
3132 		pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3133 			" Type: 0x%02x\n", (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "", type);
3134 		return TCM_INVALID_CDB_FIELD;
3135 	}
3136 }
3137 
3138 
3139 static sense_reason_t
3140 core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
3141 		u64 sa_res_key, int aptpl, int unreg)
3142 {
3143 	struct se_session *se_sess = cmd->se_sess;
3144 	struct se_device *dev = cmd->se_dev;
3145 	struct se_dev_entry *dest_se_deve = NULL;
3146 	struct se_lun *se_lun = cmd->se_lun, *tmp_lun;
3147 	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3148 	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3149 	const struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3150 	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3151 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3152 	unsigned char *buf;
3153 	const unsigned char *initiator_str;
3154 	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN] = { };
3155 	u32 tid_len, tmp_tid_len;
3156 	int new_reg = 0, type, scope, matching_iname;
3157 	sense_reason_t ret;
3158 	unsigned short rtpi;
3159 	unsigned char proto_ident;
3160 
3161 	if (!se_sess || !se_lun) {
3162 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3163 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3164 	}
3165 
3166 	se_tpg = se_sess->se_tpg;
3167 	tf_ops = se_tpg->se_tpg_tfo;
3168 	/*
3169 	 * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3170 	 *	Register behaviors for a REGISTER AND MOVE service action
3171 	 *
3172 	 * Locate the existing *pr_reg via struct se_node_acl pointers
3173 	 */
3174 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3175 				se_sess);
3176 	if (!pr_reg) {
3177 		pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3178 			" *pr_reg for REGISTER_AND_MOVE\n");
3179 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3180 	}
3181 	/*
3182 	 * The provided reservation key much match the existing reservation key
3183 	 * provided during this initiator's I_T nexus registration.
3184 	 */
3185 	if (res_key != pr_reg->pr_res_key) {
3186 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3187 			" res_key: 0x%016Lx does not match existing SA REGISTER"
3188 			" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3189 		ret = TCM_RESERVATION_CONFLICT;
3190 		goto out_put_pr_reg;
3191 	}
3192 	/*
3193 	 * The service active reservation key needs to be non zero
3194 	 */
3195 	if (!sa_res_key) {
3196 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3197 			" sa_res_key\n");
3198 		ret = TCM_INVALID_PARAMETER_LIST;
3199 		goto out_put_pr_reg;
3200 	}
3201 
3202 	/*
3203 	 * Determine the Relative Target Port Identifier where the reservation
3204 	 * will be moved to for the TransportID containing SCSI initiator WWN
3205 	 * information.
3206 	 */
3207 	buf = transport_kmap_data_sg(cmd);
3208 	if (!buf) {
3209 		ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3210 		goto out_put_pr_reg;
3211 	}
3212 
3213 	rtpi = get_unaligned_be16(&buf[18]);
3214 	tid_len = get_unaligned_be32(&buf[20]);
3215 	transport_kunmap_data_sg(cmd);
3216 	buf = NULL;
3217 
3218 	if ((tid_len + 24) != cmd->data_length) {
3219 		pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3220 			" does not equal CDB data_length: %u\n", tid_len,
3221 			cmd->data_length);
3222 		ret = TCM_INVALID_PARAMETER_LIST;
3223 		goto out_put_pr_reg;
3224 	}
3225 
3226 	spin_lock(&dev->se_port_lock);
3227 	list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
3228 		if (tmp_lun->lun_rtpi != rtpi)
3229 			continue;
3230 		dest_se_tpg = tmp_lun->lun_tpg;
3231 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3232 		if (!dest_tf_ops)
3233 			continue;
3234 
3235 		atomic_inc_mb(&dest_se_tpg->tpg_pr_ref_count);
3236 		spin_unlock(&dev->se_port_lock);
3237 
3238 		if (core_scsi3_tpg_depend_item(dest_se_tpg)) {
3239 			pr_err("core_scsi3_tpg_depend_item() failed"
3240 				" for dest_se_tpg\n");
3241 			atomic_dec_mb(&dest_se_tpg->tpg_pr_ref_count);
3242 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3243 			goto out_put_pr_reg;
3244 		}
3245 
3246 		spin_lock(&dev->se_port_lock);
3247 		break;
3248 	}
3249 	spin_unlock(&dev->se_port_lock);
3250 
3251 	if (!dest_se_tpg || !dest_tf_ops) {
3252 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3253 			" fabric ops from Relative Target Port Identifier:"
3254 			" %hu\n", rtpi);
3255 		ret = TCM_INVALID_PARAMETER_LIST;
3256 		goto out_put_pr_reg;
3257 	}
3258 
3259 	buf = transport_kmap_data_sg(cmd);
3260 	if (!buf) {
3261 		ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3262 		goto out_put_pr_reg;
3263 	}
3264 	proto_ident = (buf[24] & 0x0f);
3265 
3266 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3267 			" 0x%02x\n", proto_ident);
3268 
3269 	if (proto_ident != dest_se_tpg->proto_id) {
3270 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3271 			" proto_ident: 0x%02x does not match ident: 0x%02x"
3272 			" from fabric: %s\n", proto_ident,
3273 			dest_se_tpg->proto_id,
3274 			dest_tf_ops->fabric_name);
3275 		ret = TCM_INVALID_PARAMETER_LIST;
3276 		goto out;
3277 	}
3278 	initiator_str = target_parse_pr_out_transport_id(dest_se_tpg,
3279 			&buf[24], &tmp_tid_len, &iport_ptr);
3280 	if (!initiator_str) {
3281 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3282 			" initiator_str from Transport ID\n");
3283 		ret = TCM_INVALID_PARAMETER_LIST;
3284 		goto out;
3285 	}
3286 
3287 	transport_kunmap_data_sg(cmd);
3288 	buf = NULL;
3289 
3290 	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3291 		" %s\n", dest_tf_ops->fabric_name, (iport_ptr != NULL) ?
3292 		"port" : "device", initiator_str, (iport_ptr != NULL) ?
3293 		iport_ptr : "");
3294 	/*
3295 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3296 	 * action specifies a TransportID that is the same as the initiator port
3297 	 * of the I_T nexus for the command received, then the command shall
3298 	 * be terminated with CHECK CONDITION status, with the sense key set to
3299 	 * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3300 	 * IN PARAMETER LIST.
3301 	 */
3302 	pr_reg_nacl = pr_reg->pr_reg_nacl;
3303 	matching_iname = (!strcmp(initiator_str,
3304 				  pr_reg_nacl->initiatorname)) ? 1 : 0;
3305 	if (!matching_iname)
3306 		goto after_iport_check;
3307 
3308 	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3309 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3310 			" matches: %s on received I_T Nexus\n", initiator_str,
3311 			pr_reg_nacl->initiatorname);
3312 		ret = TCM_INVALID_PARAMETER_LIST;
3313 		goto out;
3314 	}
3315 	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3316 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3317 			" matches: %s %s on received I_T Nexus\n",
3318 			initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3319 			pr_reg->pr_reg_isid);
3320 		ret = TCM_INVALID_PARAMETER_LIST;
3321 		goto out;
3322 	}
3323 after_iport_check:
3324 	/*
3325 	 * Locate the destination struct se_node_acl from the received Transport ID
3326 	 */
3327 	mutex_lock(&dest_se_tpg->acl_node_mutex);
3328 	dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3329 				initiator_str);
3330 	if (dest_node_acl)
3331 		atomic_inc_mb(&dest_node_acl->acl_pr_ref_count);
3332 	mutex_unlock(&dest_se_tpg->acl_node_mutex);
3333 
3334 	if (!dest_node_acl) {
3335 		pr_err("Unable to locate %s dest_node_acl for"
3336 			" TransportID%s\n", dest_tf_ops->fabric_name,
3337 			initiator_str);
3338 		ret = TCM_INVALID_PARAMETER_LIST;
3339 		goto out;
3340 	}
3341 
3342 	if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
3343 		pr_err("core_scsi3_nodeacl_depend_item() for"
3344 			" dest_node_acl\n");
3345 		atomic_dec_mb(&dest_node_acl->acl_pr_ref_count);
3346 		dest_node_acl = NULL;
3347 		ret = TCM_INVALID_PARAMETER_LIST;
3348 		goto out;
3349 	}
3350 
3351 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3352 		" %s from TransportID\n", dest_tf_ops->fabric_name,
3353 		dest_node_acl->initiatorname);
3354 
3355 	/*
3356 	 * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3357 	 * PORT IDENTIFIER.
3358 	 */
3359 	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3360 	if (!dest_se_deve) {
3361 		pr_err("Unable to locate %s dest_se_deve from RTPI:"
3362 			" %hu\n",  dest_tf_ops->fabric_name, rtpi);
3363 		ret = TCM_INVALID_PARAMETER_LIST;
3364 		goto out;
3365 	}
3366 
3367 	if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
3368 		pr_err("core_scsi3_lunacl_depend_item() failed\n");
3369 		kref_put(&dest_se_deve->pr_kref, target_pr_kref_release);
3370 		dest_se_deve = NULL;
3371 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3372 		goto out;
3373 	}
3374 
3375 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3376 		" ACL for dest_se_deve->mapped_lun: %llu\n",
3377 		dest_tf_ops->fabric_name, dest_node_acl->initiatorname,
3378 		dest_se_deve->mapped_lun);
3379 
3380 	/*
3381 	 * A persistent reservation needs to already existing in order to
3382 	 * successfully complete the REGISTER_AND_MOVE service action..
3383 	 */
3384 	spin_lock(&dev->dev_reservation_lock);
3385 	pr_res_holder = dev->dev_pr_res_holder;
3386 	if (!pr_res_holder) {
3387 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3388 			" currently held\n");
3389 		spin_unlock(&dev->dev_reservation_lock);
3390 		ret = TCM_INVALID_CDB_FIELD;
3391 		goto out;
3392 	}
3393 	/*
3394 	 * The received on I_T Nexus must be the reservation holder.
3395 	 *
3396 	 * From spc4r17 section 5.7.8  Table 50 --
3397 	 * 	Register behaviors for a REGISTER AND MOVE service action
3398 	 */
3399 	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
3400 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3401 			" Nexus is not reservation holder\n");
3402 		spin_unlock(&dev->dev_reservation_lock);
3403 		ret = TCM_RESERVATION_CONFLICT;
3404 		goto out;
3405 	}
3406 	/*
3407 	 * From spc4r17 section 5.7.8: registering and moving reservation
3408 	 *
3409 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3410 	 * action is received and the established persistent reservation is a
3411 	 * Write Exclusive - All Registrants type or Exclusive Access -
3412 	 * All Registrants type reservation, then the command shall be completed
3413 	 * with RESERVATION CONFLICT status.
3414 	 */
3415 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3416 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3417 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3418 			" reservation for type: %s\n",
3419 			core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3420 		spin_unlock(&dev->dev_reservation_lock);
3421 		ret = TCM_RESERVATION_CONFLICT;
3422 		goto out;
3423 	}
3424 	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3425 	/*
3426 	 * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3427 	 */
3428 	type = pr_res_holder->pr_res_type;
3429 	scope = pr_res_holder->pr_res_type;
3430 	/*
3431 	 * c) Associate the reservation key specified in the SERVICE ACTION
3432 	 *    RESERVATION KEY field with the I_T nexus specified as the
3433 	 *    destination of the register and move, where:
3434 	 *    A) The I_T nexus is specified by the TransportID and the
3435 	 *	 RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3436 	 *    B) Regardless of the TransportID format used, the association for
3437 	 *       the initiator port is based on either the initiator port name
3438 	 *       (see 3.1.71) on SCSI transport protocols where port names are
3439 	 *       required or the initiator port identifier (see 3.1.70) on SCSI
3440 	 *       transport protocols where port names are not required;
3441 	 * d) Register the reservation key specified in the SERVICE ACTION
3442 	 *    RESERVATION KEY field;
3443 	 *
3444 	 * Also, It is not an error for a REGISTER AND MOVE service action to
3445 	 * register an I_T nexus that is already registered with the same
3446 	 * reservation key or a different reservation key.
3447 	 */
3448 	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3449 					iport_ptr);
3450 	if (!dest_pr_reg) {
3451 		struct se_lun *dest_lun = dest_se_deve->se_lun;
3452 
3453 		spin_unlock(&dev->dev_reservation_lock);
3454 		if (core_scsi3_alloc_registration(cmd->se_dev, dest_node_acl,
3455 					dest_lun, dest_se_deve, dest_se_deve->mapped_lun,
3456 					iport_ptr, sa_res_key, 0, aptpl, 2, 1)) {
3457 			ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3458 			goto out;
3459 		}
3460 		spin_lock(&dev->dev_reservation_lock);
3461 		dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3462 						iport_ptr);
3463 		new_reg = 1;
3464 	} else {
3465 		/*
3466 		 * e) Retain the reservation key specified in the SERVICE ACTION
3467 		 *    RESERVATION KEY field and associated information;
3468 		 */
3469 		dest_pr_reg->pr_res_key = sa_res_key;
3470 	}
3471 	/*
3472 	 * f) Release the persistent reservation for the persistent reservation
3473 	 *    holder (i.e., the I_T nexus on which the
3474 	 */
3475 	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
3476 					  dev->dev_pr_res_holder, 0, 0);
3477 	/*
3478 	 * g) Move the persistent reservation to the specified I_T nexus using
3479 	 *    the same scope and type as the persistent reservation released in
3480 	 *    item f); and
3481 	 */
3482 	dev->dev_pr_res_holder = dest_pr_reg;
3483 	dest_pr_reg->pr_res_holder = 1;
3484 	dest_pr_reg->pr_res_type = type;
3485 	pr_reg->pr_res_scope = scope;
3486 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
3487 	/*
3488 	 * Increment PRGeneration for existing registrations..
3489 	 */
3490 	if (!new_reg)
3491 		dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3492 	spin_unlock(&dev->dev_reservation_lock);
3493 
3494 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3495 		" created new reservation holder TYPE: %s on object RTPI:"
3496 		" %hu  PRGeneration: 0x%08x\n", dest_tf_ops->fabric_name,
3497 		core_scsi3_pr_dump_type(type), rtpi,
3498 		dest_pr_reg->pr_res_generation);
3499 	pr_debug("SPC-3 PR Successfully moved reservation from"
3500 		" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3501 		tf_ops->fabric_name, pr_reg_nacl->initiatorname,
3502 		i_buf, dest_tf_ops->fabric_name,
3503 		dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3504 		iport_ptr : "");
3505 	/*
3506 	 * It is now safe to release configfs group dependencies for destination
3507 	 * of Transport ID Initiator Device/Port Identifier
3508 	 */
3509 	core_scsi3_lunacl_undepend_item(dest_se_deve);
3510 	core_scsi3_nodeacl_undepend_item(dest_node_acl);
3511 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3512 	/*
3513 	 * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3514 	 * nexus on which PERSISTENT RESERVE OUT command was received.
3515 	 */
3516 	if (unreg) {
3517 		spin_lock(&pr_tmpl->registration_lock);
3518 		__core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3519 		spin_unlock(&pr_tmpl->registration_lock);
3520 	} else
3521 		core_scsi3_put_pr_reg(pr_reg);
3522 
3523 	core_scsi3_update_and_write_aptpl(cmd->se_dev, aptpl);
3524 
3525 	core_scsi3_put_pr_reg(dest_pr_reg);
3526 	return 0;
3527 out:
3528 	if (buf)
3529 		transport_kunmap_data_sg(cmd);
3530 	if (dest_se_deve)
3531 		core_scsi3_lunacl_undepend_item(dest_se_deve);
3532 	if (dest_node_acl)
3533 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
3534 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3535 
3536 out_put_pr_reg:
3537 	core_scsi3_put_pr_reg(pr_reg);
3538 	return ret;
3539 }
3540 
3541 /*
3542  * See spc4r17 section 6.14 Table 170
3543  */
3544 sense_reason_t
3545 target_scsi3_emulate_pr_out(struct se_cmd *cmd)
3546 {
3547 	struct se_device *dev = cmd->se_dev;
3548 	unsigned char *cdb = &cmd->t_task_cdb[0];
3549 	unsigned char *buf;
3550 	u64 res_key, sa_res_key;
3551 	int sa, scope, type, aptpl;
3552 	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3553 	sense_reason_t ret;
3554 
3555 	/*
3556 	 * Following spc2r20 5.5.1 Reservations overview:
3557 	 *
3558 	 * If a logical unit has been reserved by any RESERVE command and is
3559 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3560 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
3561 	 * initiator or service action and shall terminate with a RESERVATION
3562 	 * CONFLICT status.
3563 	 */
3564 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
3565 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3566 			" SPC-2 reservation is held, returning"
3567 			" RESERVATION_CONFLICT\n");
3568 		return TCM_RESERVATION_CONFLICT;
3569 	}
3570 
3571 	/*
3572 	 * FIXME: A NULL struct se_session pointer means an this is not coming from
3573 	 * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3574 	 */
3575 	if (!cmd->se_sess)
3576 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3577 
3578 	if (cmd->data_length < 24) {
3579 		pr_warn("SPC-PR: Received PR OUT parameter list"
3580 			" length too small: %u\n", cmd->data_length);
3581 		return TCM_PARAMETER_LIST_LENGTH_ERROR;
3582 	}
3583 
3584 	/*
3585 	 * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3586 	 */
3587 	sa = (cdb[1] & 0x1f);
3588 	scope = (cdb[2] & 0xf0);
3589 	type = (cdb[2] & 0x0f);
3590 
3591 	buf = transport_kmap_data_sg(cmd);
3592 	if (!buf)
3593 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3594 
3595 	/*
3596 	 * From PERSISTENT_RESERVE_OUT parameter list (payload)
3597 	 */
3598 	res_key = get_unaligned_be64(&buf[0]);
3599 	sa_res_key = get_unaligned_be64(&buf[8]);
3600 	/*
3601 	 * REGISTER_AND_MOVE uses a different SA parameter list containing
3602 	 * SCSI TransportIDs.
3603 	 */
3604 	if (sa != PRO_REGISTER_AND_MOVE) {
3605 		spec_i_pt = (buf[20] & 0x08);
3606 		all_tg_pt = (buf[20] & 0x04);
3607 		aptpl = (buf[20] & 0x01);
3608 	} else {
3609 		aptpl = (buf[17] & 0x01);
3610 		unreg = (buf[17] & 0x02);
3611 	}
3612 	/*
3613 	 * If the backend device has been configured to force APTPL metadata
3614 	 * write-out, go ahead and propigate aptpl=1 down now.
3615 	 */
3616 	if (dev->dev_attrib.force_pr_aptpl)
3617 		aptpl = 1;
3618 
3619 	transport_kunmap_data_sg(cmd);
3620 	buf = NULL;
3621 
3622 	/*
3623 	 * SPEC_I_PT=1 is only valid for Service action: REGISTER
3624 	 */
3625 	if (spec_i_pt && (sa != PRO_REGISTER))
3626 		return TCM_INVALID_PARAMETER_LIST;
3627 
3628 	/*
3629 	 * From spc4r17 section 6.14:
3630 	 *
3631 	 * If the SPEC_I_PT bit is set to zero, the service action is not
3632 	 * REGISTER AND MOVE, and the parameter list length is not 24, then
3633 	 * the command shall be terminated with CHECK CONDITION status, with
3634 	 * the sense key set to ILLEGAL REQUEST, and the additional sense
3635 	 * code set to PARAMETER LIST LENGTH ERROR.
3636 	 */
3637 	if (!spec_i_pt && (sa != PRO_REGISTER_AND_MOVE) &&
3638 	    (cmd->data_length != 24)) {
3639 		pr_warn("SPC-PR: Received PR OUT illegal parameter"
3640 			" list length: %u\n", cmd->data_length);
3641 		return TCM_PARAMETER_LIST_LENGTH_ERROR;
3642 	}
3643 
3644 	/*
3645 	 * (core_scsi3_emulate_pro_* function parameters
3646 	 * are defined by spc4r17 Table 174:
3647 	 * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3648 	 */
3649 	switch (sa) {
3650 	case PRO_REGISTER:
3651 		ret = core_scsi3_emulate_pro_register(cmd,
3652 			res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER);
3653 		break;
3654 	case PRO_RESERVE:
3655 		ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3656 		break;
3657 	case PRO_RELEASE:
3658 		ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3659 		break;
3660 	case PRO_CLEAR:
3661 		ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3662 		break;
3663 	case PRO_PREEMPT:
3664 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3665 					res_key, sa_res_key, PREEMPT);
3666 		break;
3667 	case PRO_PREEMPT_AND_ABORT:
3668 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3669 					res_key, sa_res_key, PREEMPT_AND_ABORT);
3670 		break;
3671 	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3672 		ret = core_scsi3_emulate_pro_register(cmd,
3673 			0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER_AND_IGNORE_EXISTING_KEY);
3674 		break;
3675 	case PRO_REGISTER_AND_MOVE:
3676 		ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3677 				sa_res_key, aptpl, unreg);
3678 		break;
3679 	default:
3680 		pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3681 			" action: 0x%02x\n", sa);
3682 		return TCM_INVALID_CDB_FIELD;
3683 	}
3684 
3685 	if (!ret)
3686 		target_complete_cmd(cmd, SAM_STAT_GOOD);
3687 	return ret;
3688 }
3689 
3690 /*
3691  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3692  *
3693  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3694  */
3695 static sense_reason_t
3696 core_scsi3_pri_read_keys(struct se_cmd *cmd)
3697 {
3698 	struct se_device *dev = cmd->se_dev;
3699 	struct t10_pr_registration *pr_reg;
3700 	unsigned char *buf;
3701 	u32 add_len = 0, off = 8;
3702 
3703 	if (cmd->data_length < 8) {
3704 		pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3705 			" too small\n", cmd->data_length);
3706 		return TCM_INVALID_CDB_FIELD;
3707 	}
3708 
3709 	buf = transport_kmap_data_sg(cmd);
3710 	if (!buf)
3711 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3712 
3713 	put_unaligned_be32(dev->t10_pr.pr_generation, buf);
3714 
3715 	spin_lock(&dev->t10_pr.registration_lock);
3716 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
3717 			pr_reg_list) {
3718 		/*
3719 		 * Check for overflow of 8byte PRI READ_KEYS payload and
3720 		 * next reservation key list descriptor.
3721 		 */
3722 		if (off + 8 <= cmd->data_length) {
3723 			put_unaligned_be64(pr_reg->pr_res_key, &buf[off]);
3724 			off += 8;
3725 		}
3726 		/*
3727 		 * SPC5r17: 6.16.2 READ KEYS service action
3728 		 * The ADDITIONAL LENGTH field indicates the number of bytes in
3729 		 * the Reservation key list. The contents of the ADDITIONAL
3730 		 * LENGTH field are not altered based on the allocation length
3731 		 */
3732 		add_len += 8;
3733 	}
3734 	spin_unlock(&dev->t10_pr.registration_lock);
3735 
3736 	put_unaligned_be32(add_len, &buf[4]);
3737 	target_set_cmd_data_length(cmd, 8 + add_len);
3738 
3739 	transport_kunmap_data_sg(cmd);
3740 
3741 	return 0;
3742 }
3743 
3744 /*
3745  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3746  *
3747  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3748  */
3749 static sense_reason_t
3750 core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3751 {
3752 	struct se_device *dev = cmd->se_dev;
3753 	struct t10_pr_registration *pr_reg;
3754 	unsigned char *buf;
3755 	u64 pr_res_key;
3756 	u32 add_len = 0;
3757 
3758 	if (cmd->data_length < 8) {
3759 		pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3760 			" too small\n", cmd->data_length);
3761 		return TCM_INVALID_CDB_FIELD;
3762 	}
3763 
3764 	buf = transport_kmap_data_sg(cmd);
3765 	if (!buf)
3766 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3767 
3768 	put_unaligned_be32(dev->t10_pr.pr_generation, &buf[0]);
3769 
3770 	spin_lock(&dev->dev_reservation_lock);
3771 	pr_reg = dev->dev_pr_res_holder;
3772 	if (pr_reg) {
3773 		/*
3774 		 * Set the Additional Length to 16 when a reservation is held
3775 		 */
3776 		add_len = 16;
3777 		put_unaligned_be32(add_len, &buf[4]);
3778 
3779 		if (cmd->data_length < 22)
3780 			goto err;
3781 
3782 		/*
3783 		 * Set the Reservation key.
3784 		 *
3785 		 * From spc4r17, section 5.7.10:
3786 		 * A persistent reservation holder has its reservation key
3787 		 * returned in the parameter data from a PERSISTENT
3788 		 * RESERVE IN command with READ RESERVATION service action as
3789 		 * follows:
3790 		 * a) For a persistent reservation of the type Write Exclusive
3791 		 *    - All Registrants or Exclusive Access ­ All Regitrants,
3792 		 *      the reservation key shall be set to zero; or
3793 		 * b) For all other persistent reservation types, the
3794 		 *    reservation key shall be set to the registered
3795 		 *    reservation key for the I_T nexus that holds the
3796 		 *    persistent reservation.
3797 		 */
3798 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3799 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3800 			pr_res_key = 0;
3801 		else
3802 			pr_res_key = pr_reg->pr_res_key;
3803 
3804 		put_unaligned_be64(pr_res_key, &buf[8]);
3805 		/*
3806 		 * Set the SCOPE and TYPE
3807 		 */
3808 		buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3809 			  (pr_reg->pr_res_type & 0x0f);
3810 	}
3811 
3812 	target_set_cmd_data_length(cmd, 8 + add_len);
3813 
3814 err:
3815 	spin_unlock(&dev->dev_reservation_lock);
3816 	transport_kunmap_data_sg(cmd);
3817 
3818 	return 0;
3819 }
3820 
3821 /*
3822  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3823  *
3824  * See spc4r17 section 6.13.4 Table 165
3825  */
3826 static sense_reason_t
3827 core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3828 {
3829 	struct se_device *dev = cmd->se_dev;
3830 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3831 	unsigned char *buf;
3832 	u16 len = 8; /* Hardcoded to 8. */
3833 
3834 	if (cmd->data_length < 6) {
3835 		pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
3836 			" %u too small\n", cmd->data_length);
3837 		return TCM_INVALID_CDB_FIELD;
3838 	}
3839 
3840 	buf = transport_kmap_data_sg(cmd);
3841 	if (!buf)
3842 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3843 
3844 	put_unaligned_be16(len, &buf[0]);
3845 	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
3846 	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
3847 	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
3848 	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
3849 	/*
3850 	 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
3851 	 * set the TMV: Task Mask Valid bit.
3852 	 */
3853 	buf[3] |= 0x80;
3854 	/*
3855 	 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
3856 	 */
3857 	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
3858 	/*
3859 	 * PTPL_A: Persistence across Target Power Loss Active bit
3860 	 */
3861 	if (pr_tmpl->pr_aptpl_active)
3862 		buf[3] |= 0x01;
3863 	/*
3864 	 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
3865 	 */
3866 	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3867 	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
3868 	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
3869 	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
3870 	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
3871 	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3872 
3873 	target_set_cmd_data_length(cmd, len);
3874 
3875 	transport_kunmap_data_sg(cmd);
3876 
3877 	return 0;
3878 }
3879 
3880 /*
3881  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
3882  *
3883  * See spc4r17 section 6.13.5 Table 168 and 169
3884  */
3885 static sense_reason_t
3886 core_scsi3_pri_read_full_status(struct se_cmd *cmd)
3887 {
3888 	struct se_device *dev = cmd->se_dev;
3889 	struct se_node_acl *se_nacl;
3890 	struct se_portal_group *se_tpg;
3891 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
3892 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3893 	unsigned char *buf;
3894 	u32 add_desc_len = 0, add_len = 0;
3895 	u32 off = 8; /* off into first Full Status descriptor */
3896 	int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
3897 	int exp_desc_len, desc_len;
3898 	bool all_reg = false;
3899 
3900 	if (cmd->data_length < 8) {
3901 		pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
3902 			" too small\n", cmd->data_length);
3903 		return TCM_INVALID_CDB_FIELD;
3904 	}
3905 
3906 	buf = transport_kmap_data_sg(cmd);
3907 	if (!buf)
3908 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3909 
3910 	put_unaligned_be32(dev->t10_pr.pr_generation, &buf[0]);
3911 
3912 	spin_lock(&dev->dev_reservation_lock);
3913 	if (dev->dev_pr_res_holder) {
3914 		struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
3915 
3916 		if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
3917 		    pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
3918 			all_reg = true;
3919 			pr_res_type = pr_holder->pr_res_type;
3920 			pr_res_scope = pr_holder->pr_res_scope;
3921 		}
3922 	}
3923 	spin_unlock(&dev->dev_reservation_lock);
3924 
3925 	spin_lock(&pr_tmpl->registration_lock);
3926 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3927 			&pr_tmpl->registration_list, pr_reg_list) {
3928 
3929 		se_nacl = pr_reg->pr_reg_nacl;
3930 		se_tpg = pr_reg->pr_reg_nacl->se_tpg;
3931 		add_desc_len = 0;
3932 
3933 		atomic_inc_mb(&pr_reg->pr_res_holders);
3934 		spin_unlock(&pr_tmpl->registration_lock);
3935 		/*
3936 		 * Determine expected length of $FABRIC_MOD specific
3937 		 * TransportID full status descriptor..
3938 		 */
3939 		exp_desc_len = target_get_pr_transport_id_len(se_nacl, pr_reg,
3940 					&format_code);
3941 		if (exp_desc_len < 0 ||
3942 		    exp_desc_len + add_len > cmd->data_length) {
3943 			pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
3944 				" out of buffer: %d\n", cmd->data_length);
3945 			spin_lock(&pr_tmpl->registration_lock);
3946 			atomic_dec_mb(&pr_reg->pr_res_holders);
3947 			break;
3948 		}
3949 		/*
3950 		 * Set RESERVATION KEY
3951 		 */
3952 		put_unaligned_be64(pr_reg->pr_res_key, &buf[off]);
3953 		off += 8;
3954 		off += 4; /* Skip Over Reserved area */
3955 
3956 		/*
3957 		 * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
3958 		 */
3959 		if (pr_reg->pr_reg_all_tg_pt)
3960 			buf[off] = 0x02;
3961 		/*
3962 		 * The struct se_lun pointer will be present for the
3963 		 * reservation holder for PR_HOLDER bit.
3964 		 *
3965 		 * Also, if this registration is the reservation
3966 		 * holder or there is an All Registrants reservation
3967 		 * active, fill in SCOPE and TYPE in the next byte.
3968 		 */
3969 		if (pr_reg->pr_res_holder) {
3970 			buf[off++] |= 0x01;
3971 			buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
3972 				     (pr_reg->pr_res_type & 0x0f);
3973 		} else if (all_reg) {
3974 			buf[off++] |= 0x01;
3975 			buf[off++] = (pr_res_scope & 0xf0) |
3976 				     (pr_res_type & 0x0f);
3977 		} else {
3978 			off += 2;
3979 		}
3980 
3981 		off += 4; /* Skip over reserved area */
3982 		/*
3983 		 * From spc4r17 6.3.15:
3984 		 *
3985 		 * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
3986 		 * IDENTIFIER field contains the relative port identifier (see
3987 		 * 3.1.120) of the target port that is part of the I_T nexus
3988 		 * described by this full status descriptor. If the ALL_TG_PT
3989 		 * bit is set to one, the contents of the RELATIVE TARGET PORT
3990 		 * IDENTIFIER field are not defined by this standard.
3991 		 */
3992 		if (!pr_reg->pr_reg_all_tg_pt) {
3993 			u16 sep_rtpi = pr_reg->tg_pt_sep_rtpi;
3994 
3995 			put_unaligned_be16(sep_rtpi, &buf[off]);
3996 			off += 2;
3997 		} else
3998 			off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */
3999 
4000 		buf[off+4] = se_tpg->proto_id;
4001 
4002 		/*
4003 		 * Now, have the $FABRIC_MOD fill in the transport ID.
4004 		 */
4005 		desc_len = target_get_pr_transport_id(se_nacl, pr_reg,
4006 				&format_code, &buf[off+4]);
4007 
4008 		spin_lock(&pr_tmpl->registration_lock);
4009 		atomic_dec_mb(&pr_reg->pr_res_holders);
4010 
4011 		if (desc_len < 0)
4012 			break;
4013 		/*
4014 		 * Set the ADDITIONAL DESCRIPTOR LENGTH
4015 		 */
4016 		put_unaligned_be32(desc_len, &buf[off]);
4017 		off += 4;
4018 		/*
4019 		 * Size of full desctipor header minus TransportID
4020 		 * containing $FABRIC_MOD specific) initiator device/port
4021 		 * WWN information.
4022 		 *
4023 		 *  See spc4r17 Section 6.13.5 Table 169
4024 		 */
4025 		add_desc_len = (24 + desc_len);
4026 
4027 		off += desc_len;
4028 		add_len += add_desc_len;
4029 	}
4030 	spin_unlock(&pr_tmpl->registration_lock);
4031 	/*
4032 	 * Set ADDITIONAL_LENGTH
4033 	 */
4034 	put_unaligned_be32(add_len, &buf[4]);
4035 	target_set_cmd_data_length(cmd, 8 + add_len);
4036 
4037 	transport_kunmap_data_sg(cmd);
4038 
4039 	return 0;
4040 }
4041 
4042 sense_reason_t
4043 target_scsi3_emulate_pr_in(struct se_cmd *cmd)
4044 {
4045 	sense_reason_t ret;
4046 
4047 	/*
4048 	 * Following spc2r20 5.5.1 Reservations overview:
4049 	 *
4050 	 * If a logical unit has been reserved by any RESERVE command and is
4051 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4052 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
4053 	 * initiator or service action and shall terminate with a RESERVATION
4054 	 * CONFLICT status.
4055 	 */
4056 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
4057 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4058 			" SPC-2 reservation is held, returning"
4059 			" RESERVATION_CONFLICT\n");
4060 		return TCM_RESERVATION_CONFLICT;
4061 	}
4062 
4063 	switch (cmd->t_task_cdb[1] & 0x1f) {
4064 	case PRI_READ_KEYS:
4065 		ret = core_scsi3_pri_read_keys(cmd);
4066 		break;
4067 	case PRI_READ_RESERVATION:
4068 		ret = core_scsi3_pri_read_reservation(cmd);
4069 		break;
4070 	case PRI_REPORT_CAPABILITIES:
4071 		ret = core_scsi3_pri_report_capabilities(cmd);
4072 		break;
4073 	case PRI_READ_FULL_STATUS:
4074 		ret = core_scsi3_pri_read_full_status(cmd);
4075 		break;
4076 	default:
4077 		pr_err("Unknown PERSISTENT_RESERVE_IN service"
4078 			" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4079 		return TCM_INVALID_CDB_FIELD;
4080 	}
4081 
4082 	if (!ret)
4083 		target_complete_cmd(cmd, SAM_STAT_GOOD);
4084 	return ret;
4085 }
4086 
4087 sense_reason_t
4088 target_check_reservation(struct se_cmd *cmd)
4089 {
4090 	struct se_device *dev = cmd->se_dev;
4091 	sense_reason_t ret;
4092 
4093 	if (!cmd->se_sess)
4094 		return 0;
4095 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
4096 		return 0;
4097 	if (!dev->dev_attrib.emulate_pr)
4098 		return 0;
4099 	if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_PGR)
4100 		return 0;
4101 
4102 	spin_lock(&dev->dev_reservation_lock);
4103 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
4104 		ret = target_scsi2_reservation_check(cmd);
4105 	else
4106 		ret = target_scsi3_pr_reservation_check(cmd);
4107 	spin_unlock(&dev->dev_reservation_lock);
4108 
4109 	return ret;
4110 }
4111