1 /*******************************************************************************
2  * Filename:  target_core_pr.c
3  *
4  * This file contains SPC-3 compliant persistent reservations and
5  * legacy SPC-2 reservations with compatible reservation handling (CRH=1)
6  *
7  * (c) Copyright 2009-2013 Datera, Inc.
8  *
9  * Nicholas A. Bellinger <nab@kernel.org>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24  *
25  ******************************************************************************/
26 
27 #include <linux/slab.h>
28 #include <linux/spinlock.h>
29 #include <linux/list.h>
30 #include <linux/file.h>
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_cmnd.h>
33 #include <asm/unaligned.h>
34 
35 #include <target/target_core_base.h>
36 #include <target/target_core_backend.h>
37 #include <target/target_core_fabric.h>
38 #include <target/target_core_configfs.h>
39 
40 #include "target_core_internal.h"
41 #include "target_core_pr.h"
42 #include "target_core_ua.h"
43 
44 /*
45  * Used for Specify Initiator Ports Capable Bit (SPEC_I_PT)
46  */
47 struct pr_transport_id_holder {
48 	int dest_local_nexus;
49 	struct t10_pr_registration *dest_pr_reg;
50 	struct se_portal_group *dest_tpg;
51 	struct se_node_acl *dest_node_acl;
52 	struct se_dev_entry *dest_se_deve;
53 	struct list_head dest_list;
54 };
55 
56 void core_pr_dump_initiator_port(
57 	struct t10_pr_registration *pr_reg,
58 	char *buf,
59 	u32 size)
60 {
61 	if (!pr_reg->isid_present_at_reg)
62 		buf[0] = '\0';
63 
64 	snprintf(buf, size, ",i,0x%s", pr_reg->pr_reg_isid);
65 }
66 
67 enum register_type {
68 	REGISTER,
69 	REGISTER_AND_IGNORE_EXISTING_KEY,
70 	REGISTER_AND_MOVE,
71 };
72 
73 enum preempt_type {
74 	PREEMPT,
75 	PREEMPT_AND_ABORT,
76 };
77 
78 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
79 			struct t10_pr_registration *, int);
80 
81 static sense_reason_t
82 target_scsi2_reservation_check(struct se_cmd *cmd)
83 {
84 	struct se_device *dev = cmd->se_dev;
85 	struct se_session *sess = cmd->se_sess;
86 
87 	switch (cmd->t_task_cdb[0]) {
88 	case INQUIRY:
89 	case RELEASE:
90 	case RELEASE_10:
91 		return 0;
92 	default:
93 		break;
94 	}
95 
96 	if (!dev->dev_reserved_node_acl || !sess)
97 		return 0;
98 
99 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
100 		return TCM_RESERVATION_CONFLICT;
101 
102 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
103 		if (dev->dev_res_bin_isid != sess->sess_bin_isid)
104 			return TCM_RESERVATION_CONFLICT;
105 	}
106 
107 	return 0;
108 }
109 
110 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
111 					struct se_node_acl *, struct se_session *);
112 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
113 
114 static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
115 {
116 	struct se_session *se_sess = cmd->se_sess;
117 	struct se_device *dev = cmd->se_dev;
118 	struct t10_pr_registration *pr_reg;
119 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
120 	int conflict = 0;
121 
122 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
123 			se_sess);
124 	if (pr_reg) {
125 		/*
126 		 * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
127 		 * behavior
128 		 *
129 		 * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
130 		 * status, but no reservation shall be established and the
131 		 * persistent reservation shall not be changed, if the command
132 		 * is received from a) and b) below.
133 		 *
134 		 * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
135 		 * status, but the persistent reservation shall not be released,
136 		 * if the command is received from a) and b)
137 		 *
138 		 * a) An I_T nexus that is a persistent reservation holder; or
139 		 * b) An I_T nexus that is registered if a registrants only or
140 		 *    all registrants type persistent reservation is present.
141 		 *
142 		 * In all other cases, a RESERVE(6) command, RESERVE(10) command,
143 		 * RELEASE(6) command, or RELEASE(10) command shall be processed
144 		 * as defined in SPC-2.
145 		 */
146 		if (pr_reg->pr_res_holder) {
147 			core_scsi3_put_pr_reg(pr_reg);
148 			return 1;
149 		}
150 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
151 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
152 		    (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
153 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
154 			core_scsi3_put_pr_reg(pr_reg);
155 			return 1;
156 		}
157 		core_scsi3_put_pr_reg(pr_reg);
158 		conflict = 1;
159 	} else {
160 		/*
161 		 * Following spc2r20 5.5.1 Reservations overview:
162 		 *
163 		 * If a logical unit has executed a PERSISTENT RESERVE OUT
164 		 * command with the REGISTER or the REGISTER AND IGNORE
165 		 * EXISTING KEY service action and is still registered by any
166 		 * initiator, all RESERVE commands and all RELEASE commands
167 		 * regardless of initiator shall conflict and shall terminate
168 		 * with a RESERVATION CONFLICT status.
169 		 */
170 		spin_lock(&pr_tmpl->registration_lock);
171 		conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
172 		spin_unlock(&pr_tmpl->registration_lock);
173 	}
174 
175 	if (conflict) {
176 		pr_err("Received legacy SPC-2 RESERVE/RELEASE"
177 			" while active SPC-3 registrations exist,"
178 			" returning RESERVATION_CONFLICT\n");
179 		return -EBUSY;
180 	}
181 
182 	return 0;
183 }
184 
185 sense_reason_t
186 target_scsi2_reservation_release(struct se_cmd *cmd)
187 {
188 	struct se_device *dev = cmd->se_dev;
189 	struct se_session *sess = cmd->se_sess;
190 	struct se_portal_group *tpg;
191 	int rc;
192 
193 	if (!sess || !sess->se_tpg)
194 		goto out;
195 	rc = target_check_scsi2_reservation_conflict(cmd);
196 	if (rc == 1)
197 		goto out;
198 	if (rc < 0)
199 		return TCM_RESERVATION_CONFLICT;
200 
201 	spin_lock(&dev->dev_reservation_lock);
202 	if (!dev->dev_reserved_node_acl || !sess)
203 		goto out_unlock;
204 
205 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
206 		goto out_unlock;
207 
208 	if (dev->dev_res_bin_isid != sess->sess_bin_isid)
209 		goto out_unlock;
210 
211 	dev->dev_reserved_node_acl = NULL;
212 	dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
213 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
214 		dev->dev_res_bin_isid = 0;
215 		dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS_WITH_ISID;
216 	}
217 	tpg = sess->se_tpg;
218 	pr_debug("SCSI-2 Released reservation for %s LUN: %u ->"
219 		" MAPPED LUN: %u for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
220 		cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
221 		sess->se_node_acl->initiatorname);
222 
223 out_unlock:
224 	spin_unlock(&dev->dev_reservation_lock);
225 out:
226 	target_complete_cmd(cmd, GOOD);
227 	return 0;
228 }
229 
230 sense_reason_t
231 target_scsi2_reservation_reserve(struct se_cmd *cmd)
232 {
233 	struct se_device *dev = cmd->se_dev;
234 	struct se_session *sess = cmd->se_sess;
235 	struct se_portal_group *tpg;
236 	sense_reason_t ret = 0;
237 	int rc;
238 
239 	if ((cmd->t_task_cdb[1] & 0x01) &&
240 	    (cmd->t_task_cdb[1] & 0x02)) {
241 		pr_err("LongIO and Obselete Bits set, returning"
242 				" ILLEGAL_REQUEST\n");
243 		return TCM_UNSUPPORTED_SCSI_OPCODE;
244 	}
245 	/*
246 	 * This is currently the case for target_core_mod passthrough struct se_cmd
247 	 * ops
248 	 */
249 	if (!sess || !sess->se_tpg)
250 		goto out;
251 	rc = target_check_scsi2_reservation_conflict(cmd);
252 	if (rc == 1)
253 		goto out;
254 
255 	if (rc < 0)
256 		return TCM_RESERVATION_CONFLICT;
257 
258 	tpg = sess->se_tpg;
259 	spin_lock(&dev->dev_reservation_lock);
260 	if (dev->dev_reserved_node_acl &&
261 	   (dev->dev_reserved_node_acl != sess->se_node_acl)) {
262 		pr_err("SCSI-2 RESERVATION CONFLIFT for %s fabric\n",
263 			tpg->se_tpg_tfo->get_fabric_name());
264 		pr_err("Original reserver LUN: %u %s\n",
265 			cmd->se_lun->unpacked_lun,
266 			dev->dev_reserved_node_acl->initiatorname);
267 		pr_err("Current attempt - LUN: %u -> MAPPED LUN: %u"
268 			" from %s \n", cmd->se_lun->unpacked_lun,
269 			cmd->se_deve->mapped_lun,
270 			sess->se_node_acl->initiatorname);
271 		ret = TCM_RESERVATION_CONFLICT;
272 		goto out_unlock;
273 	}
274 
275 	dev->dev_reserved_node_acl = sess->se_node_acl;
276 	dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS;
277 	if (sess->sess_bin_isid != 0) {
278 		dev->dev_res_bin_isid = sess->sess_bin_isid;
279 		dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS_WITH_ISID;
280 	}
281 	pr_debug("SCSI-2 Reserved %s LUN: %u -> MAPPED LUN: %u"
282 		" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
283 		cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
284 		sess->se_node_acl->initiatorname);
285 
286 out_unlock:
287 	spin_unlock(&dev->dev_reservation_lock);
288 out:
289 	if (!ret)
290 		target_complete_cmd(cmd, GOOD);
291 	return ret;
292 }
293 
294 
295 /*
296  * Begin SPC-3/SPC-4 Persistent Reservations emulation support
297  *
298  * This function is called by those initiator ports who are *NOT*
299  * the active PR reservation holder when a reservation is present.
300  */
301 static int core_scsi3_pr_seq_non_holder(
302 	struct se_cmd *cmd,
303 	u32 pr_reg_type)
304 {
305 	unsigned char *cdb = cmd->t_task_cdb;
306 	struct se_dev_entry *se_deve;
307 	struct se_session *se_sess = cmd->se_sess;
308 	int other_cdb = 0, ignore_reg;
309 	int registered_nexus = 0, ret = 1; /* Conflict by default */
310 	int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
311 	int we = 0; /* Write Exclusive */
312 	int legacy = 0; /* Act like a legacy device and return
313 			 * RESERVATION CONFLICT on some CDBs */
314 
315 	se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
316 	/*
317 	 * Determine if the registration should be ignored due to
318 	 * non-matching ISIDs in target_scsi3_pr_reservation_check().
319 	 */
320 	ignore_reg = (pr_reg_type & 0x80000000);
321 	if (ignore_reg)
322 		pr_reg_type &= ~0x80000000;
323 
324 	switch (pr_reg_type) {
325 	case PR_TYPE_WRITE_EXCLUSIVE:
326 		we = 1;
327 	case PR_TYPE_EXCLUSIVE_ACCESS:
328 		/*
329 		 * Some commands are only allowed for the persistent reservation
330 		 * holder.
331 		 */
332 		if ((se_deve->def_pr_registered) && !(ignore_reg))
333 			registered_nexus = 1;
334 		break;
335 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
336 		we = 1;
337 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
338 		/*
339 		 * Some commands are only allowed for registered I_T Nexuses.
340 		 */
341 		reg_only = 1;
342 		if ((se_deve->def_pr_registered) && !(ignore_reg))
343 			registered_nexus = 1;
344 		break;
345 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
346 		we = 1;
347 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
348 		/*
349 		 * Each registered I_T Nexus is a reservation holder.
350 		 */
351 		all_reg = 1;
352 		if ((se_deve->def_pr_registered) && !(ignore_reg))
353 			registered_nexus = 1;
354 		break;
355 	default:
356 		return -EINVAL;
357 	}
358 	/*
359 	 * Referenced from spc4r17 table 45 for *NON* PR holder access
360 	 */
361 	switch (cdb[0]) {
362 	case SECURITY_PROTOCOL_IN:
363 		if (registered_nexus)
364 			return 0;
365 		ret = (we) ? 0 : 1;
366 		break;
367 	case MODE_SENSE:
368 	case MODE_SENSE_10:
369 	case READ_ATTRIBUTE:
370 	case READ_BUFFER:
371 	case RECEIVE_DIAGNOSTIC:
372 		if (legacy) {
373 			ret = 1;
374 			break;
375 		}
376 		if (registered_nexus) {
377 			ret = 0;
378 			break;
379 		}
380 		ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
381 		break;
382 	case PERSISTENT_RESERVE_OUT:
383 		/*
384 		 * This follows PERSISTENT_RESERVE_OUT service actions that
385 		 * are allowed in the presence of various reservations.
386 		 * See spc4r17, table 46
387 		 */
388 		switch (cdb[1] & 0x1f) {
389 		case PRO_CLEAR:
390 		case PRO_PREEMPT:
391 		case PRO_PREEMPT_AND_ABORT:
392 			ret = (registered_nexus) ? 0 : 1;
393 			break;
394 		case PRO_REGISTER:
395 		case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
396 			ret = 0;
397 			break;
398 		case PRO_REGISTER_AND_MOVE:
399 		case PRO_RESERVE:
400 			ret = 1;
401 			break;
402 		case PRO_RELEASE:
403 			ret = (registered_nexus) ? 0 : 1;
404 			break;
405 		default:
406 			pr_err("Unknown PERSISTENT_RESERVE_OUT service"
407 				" action: 0x%02x\n", cdb[1] & 0x1f);
408 			return -EINVAL;
409 		}
410 		break;
411 	case RELEASE:
412 	case RELEASE_10:
413 		/* Handled by CRH=1 in target_scsi2_reservation_release() */
414 		ret = 0;
415 		break;
416 	case RESERVE:
417 	case RESERVE_10:
418 		/* Handled by CRH=1 in target_scsi2_reservation_reserve() */
419 		ret = 0;
420 		break;
421 	case TEST_UNIT_READY:
422 		ret = (legacy) ? 1 : 0; /* Conflict for legacy */
423 		break;
424 	case MAINTENANCE_IN:
425 		switch (cdb[1] & 0x1f) {
426 		case MI_MANAGEMENT_PROTOCOL_IN:
427 			if (registered_nexus) {
428 				ret = 0;
429 				break;
430 			}
431 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
432 			break;
433 		case MI_REPORT_SUPPORTED_OPERATION_CODES:
434 		case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
435 			if (legacy) {
436 				ret = 1;
437 				break;
438 			}
439 			if (registered_nexus) {
440 				ret = 0;
441 				break;
442 			}
443 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
444 			break;
445 		case MI_REPORT_ALIASES:
446 		case MI_REPORT_IDENTIFYING_INFORMATION:
447 		case MI_REPORT_PRIORITY:
448 		case MI_REPORT_TARGET_PGS:
449 		case MI_REPORT_TIMESTAMP:
450 			ret = 0; /* Allowed */
451 			break;
452 		default:
453 			pr_err("Unknown MI Service Action: 0x%02x\n",
454 				(cdb[1] & 0x1f));
455 			return -EINVAL;
456 		}
457 		break;
458 	case ACCESS_CONTROL_IN:
459 	case ACCESS_CONTROL_OUT:
460 	case INQUIRY:
461 	case LOG_SENSE:
462 	case READ_MEDIA_SERIAL_NUMBER:
463 	case REPORT_LUNS:
464 	case REQUEST_SENSE:
465 	case PERSISTENT_RESERVE_IN:
466 		ret = 0; /*/ Allowed CDBs */
467 		break;
468 	default:
469 		other_cdb = 1;
470 		break;
471 	}
472 	/*
473 	 * Case where the CDB is explicitly allowed in the above switch
474 	 * statement.
475 	 */
476 	if (!ret && !other_cdb) {
477 		pr_debug("Allowing explicit CDB: 0x%02x for %s"
478 			" reservation holder\n", cdb[0],
479 			core_scsi3_pr_dump_type(pr_reg_type));
480 
481 		return ret;
482 	}
483 	/*
484 	 * Check if write exclusive initiator ports *NOT* holding the
485 	 * WRITE_EXCLUSIVE_* reservation.
486 	 */
487 	if (we && !registered_nexus) {
488 		if (cmd->data_direction == DMA_TO_DEVICE) {
489 			/*
490 			 * Conflict for write exclusive
491 			 */
492 			pr_debug("%s Conflict for unregistered nexus"
493 				" %s CDB: 0x%02x to %s reservation\n",
494 				transport_dump_cmd_direction(cmd),
495 				se_sess->se_node_acl->initiatorname, cdb[0],
496 				core_scsi3_pr_dump_type(pr_reg_type));
497 			return 1;
498 		} else {
499 			/*
500 			 * Allow non WRITE CDBs for all Write Exclusive
501 			 * PR TYPEs to pass for registered and
502 			 * non-registered_nexuxes NOT holding the reservation.
503 			 *
504 			 * We only make noise for the unregisterd nexuses,
505 			 * as we expect registered non-reservation holding
506 			 * nexuses to issue CDBs.
507 			 */
508 
509 			if (!registered_nexus) {
510 				pr_debug("Allowing implicit CDB: 0x%02x"
511 					" for %s reservation on unregistered"
512 					" nexus\n", cdb[0],
513 					core_scsi3_pr_dump_type(pr_reg_type));
514 			}
515 
516 			return 0;
517 		}
518 	} else if ((reg_only) || (all_reg)) {
519 		if (registered_nexus) {
520 			/*
521 			 * For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
522 			 * allow commands from registered nexuses.
523 			 */
524 
525 			pr_debug("Allowing implicit CDB: 0x%02x for %s"
526 				" reservation\n", cdb[0],
527 				core_scsi3_pr_dump_type(pr_reg_type));
528 
529 			return 0;
530 		}
531 	}
532 	pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
533 		" for %s reservation\n", transport_dump_cmd_direction(cmd),
534 		(registered_nexus) ? "" : "un",
535 		se_sess->se_node_acl->initiatorname, cdb[0],
536 		core_scsi3_pr_dump_type(pr_reg_type));
537 
538 	return 1; /* Conflict by default */
539 }
540 
541 static sense_reason_t
542 target_scsi3_pr_reservation_check(struct se_cmd *cmd)
543 {
544 	struct se_device *dev = cmd->se_dev;
545 	struct se_session *sess = cmd->se_sess;
546 	u32 pr_reg_type;
547 
548 	if (!dev->dev_pr_res_holder)
549 		return 0;
550 
551 	pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
552 	cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
553 	if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
554 		goto check_nonholder;
555 
556 	if (dev->dev_pr_res_holder->isid_present_at_reg) {
557 		if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
558 		    sess->sess_bin_isid) {
559 			pr_reg_type |= 0x80000000;
560 			goto check_nonholder;
561 		}
562 	}
563 
564 	return 0;
565 
566 check_nonholder:
567 	if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type))
568 		return TCM_RESERVATION_CONFLICT;
569 	return 0;
570 }
571 
572 static u32 core_scsi3_pr_generation(struct se_device *dev)
573 {
574 	u32 prg;
575 
576 	/*
577 	 * PRGeneration field shall contain the value of a 32-bit wrapping
578 	 * counter mainted by the device server.
579 	 *
580 	 * Note that this is done regardless of Active Persist across
581 	 * Target PowerLoss (APTPL)
582 	 *
583 	 * See spc4r17 section 6.3.12 READ_KEYS service action
584 	 */
585 	spin_lock(&dev->dev_reservation_lock);
586 	prg = dev->t10_pr.pr_generation++;
587 	spin_unlock(&dev->dev_reservation_lock);
588 
589 	return prg;
590 }
591 
592 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
593 	struct se_device *dev,
594 	struct se_node_acl *nacl,
595 	struct se_dev_entry *deve,
596 	unsigned char *isid,
597 	u64 sa_res_key,
598 	int all_tg_pt,
599 	int aptpl)
600 {
601 	struct t10_pr_registration *pr_reg;
602 
603 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_ATOMIC);
604 	if (!pr_reg) {
605 		pr_err("Unable to allocate struct t10_pr_registration\n");
606 		return NULL;
607 	}
608 
609 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
610 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
611 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
612 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
613 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
614 	atomic_set(&pr_reg->pr_res_holders, 0);
615 	pr_reg->pr_reg_nacl = nacl;
616 	pr_reg->pr_reg_deve = deve;
617 	pr_reg->pr_res_mapped_lun = deve->mapped_lun;
618 	pr_reg->pr_aptpl_target_lun = deve->se_lun->unpacked_lun;
619 	pr_reg->pr_res_key = sa_res_key;
620 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
621 	pr_reg->pr_reg_aptpl = aptpl;
622 	pr_reg->pr_reg_tg_pt_lun = deve->se_lun;
623 	/*
624 	 * If an ISID value for this SCSI Initiator Port exists,
625 	 * save it to the registration now.
626 	 */
627 	if (isid != NULL) {
628 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
629 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
630 		pr_reg->isid_present_at_reg = 1;
631 	}
632 
633 	return pr_reg;
634 }
635 
636 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
637 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
638 
639 /*
640  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
641  * modes.
642  */
643 static struct t10_pr_registration *__core_scsi3_alloc_registration(
644 	struct se_device *dev,
645 	struct se_node_acl *nacl,
646 	struct se_dev_entry *deve,
647 	unsigned char *isid,
648 	u64 sa_res_key,
649 	int all_tg_pt,
650 	int aptpl)
651 {
652 	struct se_dev_entry *deve_tmp;
653 	struct se_node_acl *nacl_tmp;
654 	struct se_port *port, *port_tmp;
655 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
656 	struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
657 	int ret;
658 	/*
659 	 * Create a registration for the I_T Nexus upon which the
660 	 * PROUT REGISTER was received.
661 	 */
662 	pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, deve, isid,
663 			sa_res_key, all_tg_pt, aptpl);
664 	if (!pr_reg)
665 		return NULL;
666 	/*
667 	 * Return pointer to pr_reg for ALL_TG_PT=0
668 	 */
669 	if (!all_tg_pt)
670 		return pr_reg;
671 	/*
672 	 * Create list of matching SCSI Initiator Port registrations
673 	 * for ALL_TG_PT=1
674 	 */
675 	spin_lock(&dev->se_port_lock);
676 	list_for_each_entry_safe(port, port_tmp, &dev->dev_sep_list, sep_list) {
677 		atomic_inc(&port->sep_tg_pt_ref_cnt);
678 		smp_mb__after_atomic_inc();
679 		spin_unlock(&dev->se_port_lock);
680 
681 		spin_lock_bh(&port->sep_alua_lock);
682 		list_for_each_entry(deve_tmp, &port->sep_alua_list,
683 					alua_port_list) {
684 			/*
685 			 * This pointer will be NULL for demo mode MappedLUNs
686 			 * that have not been make explicit via a ConfigFS
687 			 * MappedLUN group for the SCSI Initiator Node ACL.
688 			 */
689 			if (!deve_tmp->se_lun_acl)
690 				continue;
691 
692 			nacl_tmp = deve_tmp->se_lun_acl->se_lun_nacl;
693 			/*
694 			 * Skip the matching struct se_node_acl that is allocated
695 			 * above..
696 			 */
697 			if (nacl == nacl_tmp)
698 				continue;
699 			/*
700 			 * Only perform PR registrations for target ports on
701 			 * the same fabric module as the REGISTER w/ ALL_TG_PT=1
702 			 * arrived.
703 			 */
704 			if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
705 				continue;
706 			/*
707 			 * Look for a matching Initiator Node ACL in ASCII format
708 			 */
709 			if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
710 				continue;
711 
712 			atomic_inc(&deve_tmp->pr_ref_count);
713 			smp_mb__after_atomic_inc();
714 			spin_unlock_bh(&port->sep_alua_lock);
715 			/*
716 			 * Grab a configfs group dependency that is released
717 			 * for the exception path at label out: below, or upon
718 			 * completion of adding ALL_TG_PT=1 registrations in
719 			 * __core_scsi3_add_registration()
720 			 */
721 			ret = core_scsi3_lunacl_depend_item(deve_tmp);
722 			if (ret < 0) {
723 				pr_err("core_scsi3_lunacl_depend"
724 						"_item() failed\n");
725 				atomic_dec(&port->sep_tg_pt_ref_cnt);
726 				smp_mb__after_atomic_dec();
727 				atomic_dec(&deve_tmp->pr_ref_count);
728 				smp_mb__after_atomic_dec();
729 				goto out;
730 			}
731 			/*
732 			 * Located a matching SCSI Initiator Port on a different
733 			 * port, allocate the pr_reg_atp and attach it to the
734 			 * pr_reg->pr_reg_atp_list that will be processed once
735 			 * the original *pr_reg is processed in
736 			 * __core_scsi3_add_registration()
737 			 */
738 			pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
739 						nacl_tmp, deve_tmp, NULL,
740 						sa_res_key, all_tg_pt, aptpl);
741 			if (!pr_reg_atp) {
742 				atomic_dec(&port->sep_tg_pt_ref_cnt);
743 				smp_mb__after_atomic_dec();
744 				atomic_dec(&deve_tmp->pr_ref_count);
745 				smp_mb__after_atomic_dec();
746 				core_scsi3_lunacl_undepend_item(deve_tmp);
747 				goto out;
748 			}
749 
750 			list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
751 				      &pr_reg->pr_reg_atp_list);
752 			spin_lock_bh(&port->sep_alua_lock);
753 		}
754 		spin_unlock_bh(&port->sep_alua_lock);
755 
756 		spin_lock(&dev->se_port_lock);
757 		atomic_dec(&port->sep_tg_pt_ref_cnt);
758 		smp_mb__after_atomic_dec();
759 	}
760 	spin_unlock(&dev->se_port_lock);
761 
762 	return pr_reg;
763 out:
764 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
765 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
766 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
767 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
768 		kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
769 	}
770 	kmem_cache_free(t10_pr_reg_cache, pr_reg);
771 	return NULL;
772 }
773 
774 int core_scsi3_alloc_aptpl_registration(
775 	struct t10_reservation *pr_tmpl,
776 	u64 sa_res_key,
777 	unsigned char *i_port,
778 	unsigned char *isid,
779 	u32 mapped_lun,
780 	unsigned char *t_port,
781 	u16 tpgt,
782 	u32 target_lun,
783 	int res_holder,
784 	int all_tg_pt,
785 	u8 type)
786 {
787 	struct t10_pr_registration *pr_reg;
788 
789 	if (!i_port || !t_port || !sa_res_key) {
790 		pr_err("Illegal parameters for APTPL registration\n");
791 		return -EINVAL;
792 	}
793 
794 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
795 	if (!pr_reg) {
796 		pr_err("Unable to allocate struct t10_pr_registration\n");
797 		return -ENOMEM;
798 	}
799 
800 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
801 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
802 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
803 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
804 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
805 	atomic_set(&pr_reg->pr_res_holders, 0);
806 	pr_reg->pr_reg_nacl = NULL;
807 	pr_reg->pr_reg_deve = NULL;
808 	pr_reg->pr_res_mapped_lun = mapped_lun;
809 	pr_reg->pr_aptpl_target_lun = target_lun;
810 	pr_reg->pr_res_key = sa_res_key;
811 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
812 	pr_reg->pr_reg_aptpl = 1;
813 	pr_reg->pr_reg_tg_pt_lun = NULL;
814 	pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
815 	pr_reg->pr_res_type = type;
816 	/*
817 	 * If an ISID value had been saved in APTPL metadata for this
818 	 * SCSI Initiator Port, restore it now.
819 	 */
820 	if (isid != NULL) {
821 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
822 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
823 		pr_reg->isid_present_at_reg = 1;
824 	}
825 	/*
826 	 * Copy the i_port and t_port information from caller.
827 	 */
828 	snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
829 	snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
830 	pr_reg->pr_reg_tpgt = tpgt;
831 	/*
832 	 * Set pr_res_holder from caller, the pr_reg who is the reservation
833 	 * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
834 	 * the Initiator Node LUN ACL from the fabric module is created for
835 	 * this registration.
836 	 */
837 	pr_reg->pr_res_holder = res_holder;
838 
839 	list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
840 	pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
841 			" metadata\n", (res_holder) ? "+reservation" : "");
842 	return 0;
843 }
844 
845 static void core_scsi3_aptpl_reserve(
846 	struct se_device *dev,
847 	struct se_portal_group *tpg,
848 	struct se_node_acl *node_acl,
849 	struct t10_pr_registration *pr_reg)
850 {
851 	char i_buf[PR_REG_ISID_ID_LEN];
852 
853 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
854 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
855 
856 	spin_lock(&dev->dev_reservation_lock);
857 	dev->dev_pr_res_holder = pr_reg;
858 	spin_unlock(&dev->dev_reservation_lock);
859 
860 	pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
861 		" new reservation holder TYPE: %s ALL_TG_PT: %d\n",
862 		tpg->se_tpg_tfo->get_fabric_name(),
863 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
864 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
865 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
866 		tpg->se_tpg_tfo->get_fabric_name(), node_acl->initiatorname,
867 		i_buf);
868 }
869 
870 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
871 				struct t10_pr_registration *, enum register_type, int);
872 
873 static int __core_scsi3_check_aptpl_registration(
874 	struct se_device *dev,
875 	struct se_portal_group *tpg,
876 	struct se_lun *lun,
877 	u32 target_lun,
878 	struct se_node_acl *nacl,
879 	struct se_dev_entry *deve)
880 {
881 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
882 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
883 	unsigned char i_port[PR_APTPL_MAX_IPORT_LEN];
884 	unsigned char t_port[PR_APTPL_MAX_TPORT_LEN];
885 	u16 tpgt;
886 
887 	memset(i_port, 0, PR_APTPL_MAX_IPORT_LEN);
888 	memset(t_port, 0, PR_APTPL_MAX_TPORT_LEN);
889 	/*
890 	 * Copy Initiator Port information from struct se_node_acl
891 	 */
892 	snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
893 	snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
894 			tpg->se_tpg_tfo->tpg_get_wwn(tpg));
895 	tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
896 	/*
897 	 * Look for the matching registrations+reservation from those
898 	 * created from APTPL metadata.  Note that multiple registrations
899 	 * may exist for fabrics that use ISIDs in their SCSI Initiator Port
900 	 * TransportIDs.
901 	 */
902 	spin_lock(&pr_tmpl->aptpl_reg_lock);
903 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
904 				pr_reg_aptpl_list) {
905 		if (!strcmp(pr_reg->pr_iport, i_port) &&
906 		     (pr_reg->pr_res_mapped_lun == deve->mapped_lun) &&
907 		    !(strcmp(pr_reg->pr_tport, t_port)) &&
908 		     (pr_reg->pr_reg_tpgt == tpgt) &&
909 		     (pr_reg->pr_aptpl_target_lun == target_lun)) {
910 
911 			pr_reg->pr_reg_nacl = nacl;
912 			pr_reg->pr_reg_deve = deve;
913 			pr_reg->pr_reg_tg_pt_lun = lun;
914 
915 			list_del(&pr_reg->pr_reg_aptpl_list);
916 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
917 			/*
918 			 * At this point all of the pointers in *pr_reg will
919 			 * be setup, so go ahead and add the registration.
920 			 */
921 
922 			__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
923 			/*
924 			 * If this registration is the reservation holder,
925 			 * make that happen now..
926 			 */
927 			if (pr_reg->pr_res_holder)
928 				core_scsi3_aptpl_reserve(dev, tpg,
929 						nacl, pr_reg);
930 			/*
931 			 * Reenable pr_aptpl_active to accept new metadata
932 			 * updates once the SCSI device is active again..
933 			 */
934 			spin_lock(&pr_tmpl->aptpl_reg_lock);
935 			pr_tmpl->pr_aptpl_active = 1;
936 		}
937 	}
938 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
939 
940 	return 0;
941 }
942 
943 int core_scsi3_check_aptpl_registration(
944 	struct se_device *dev,
945 	struct se_portal_group *tpg,
946 	struct se_lun *lun,
947 	struct se_lun_acl *lun_acl)
948 {
949 	struct se_node_acl *nacl = lun_acl->se_lun_nacl;
950 	struct se_dev_entry *deve = nacl->device_list[lun_acl->mapped_lun];
951 
952 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
953 		return 0;
954 
955 	return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
956 				lun->unpacked_lun, nacl, deve);
957 }
958 
959 static void __core_scsi3_dump_registration(
960 	struct target_core_fabric_ops *tfo,
961 	struct se_device *dev,
962 	struct se_node_acl *nacl,
963 	struct t10_pr_registration *pr_reg,
964 	enum register_type register_type)
965 {
966 	struct se_portal_group *se_tpg = nacl->se_tpg;
967 	char i_buf[PR_REG_ISID_ID_LEN];
968 
969 	memset(&i_buf[0], 0, PR_REG_ISID_ID_LEN);
970 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
971 
972 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
973 		" Node: %s%s\n", tfo->get_fabric_name(), (register_type == REGISTER_AND_MOVE) ?
974 		"_AND_MOVE" : (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ?
975 		"_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
976 		i_buf);
977 	pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
978 		 tfo->get_fabric_name(), tfo->tpg_get_wwn(se_tpg),
979 		tfo->tpg_get_tag(se_tpg));
980 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
981 		" Port(s)\n",  tfo->get_fabric_name(),
982 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
983 		dev->transport->name);
984 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
985 		" 0x%08x  APTPL: %d\n", tfo->get_fabric_name(),
986 		pr_reg->pr_res_key, pr_reg->pr_res_generation,
987 		pr_reg->pr_reg_aptpl);
988 }
989 
990 /*
991  * this function can be called with struct se_device->dev_reservation_lock
992  * when register_move = 1
993  */
994 static void __core_scsi3_add_registration(
995 	struct se_device *dev,
996 	struct se_node_acl *nacl,
997 	struct t10_pr_registration *pr_reg,
998 	enum register_type register_type,
999 	int register_move)
1000 {
1001 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1002 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1003 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1004 
1005 	/*
1006 	 * Increment PRgeneration counter for struct se_device upon a successful
1007 	 * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1008 	 *
1009 	 * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1010 	 * action, the struct se_device->dev_reservation_lock will already be held,
1011 	 * so we do not call core_scsi3_pr_generation() which grabs the lock
1012 	 * for the REGISTER.
1013 	 */
1014 	pr_reg->pr_res_generation = (register_move) ?
1015 			dev->t10_pr.pr_generation++ :
1016 			core_scsi3_pr_generation(dev);
1017 
1018 	spin_lock(&pr_tmpl->registration_lock);
1019 	list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1020 	pr_reg->pr_reg_deve->def_pr_registered = 1;
1021 
1022 	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1023 	spin_unlock(&pr_tmpl->registration_lock);
1024 	/*
1025 	 * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1026 	 */
1027 	if (!pr_reg->pr_reg_all_tg_pt || register_move)
1028 		return;
1029 	/*
1030 	 * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1031 	 * allocated in __core_scsi3_alloc_registration()
1032 	 */
1033 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1034 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1035 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1036 
1037 		pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1038 
1039 		spin_lock(&pr_tmpl->registration_lock);
1040 		list_add_tail(&pr_reg_tmp->pr_reg_list,
1041 			      &pr_tmpl->registration_list);
1042 		pr_reg_tmp->pr_reg_deve->def_pr_registered = 1;
1043 
1044 		__core_scsi3_dump_registration(tfo, dev,
1045 				pr_reg_tmp->pr_reg_nacl, pr_reg_tmp,
1046 				register_type);
1047 		spin_unlock(&pr_tmpl->registration_lock);
1048 		/*
1049 		 * Drop configfs group dependency reference from
1050 		 * __core_scsi3_alloc_registration()
1051 		 */
1052 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1053 	}
1054 }
1055 
1056 static int core_scsi3_alloc_registration(
1057 	struct se_device *dev,
1058 	struct se_node_acl *nacl,
1059 	struct se_dev_entry *deve,
1060 	unsigned char *isid,
1061 	u64 sa_res_key,
1062 	int all_tg_pt,
1063 	int aptpl,
1064 	enum register_type register_type,
1065 	int register_move)
1066 {
1067 	struct t10_pr_registration *pr_reg;
1068 
1069 	pr_reg = __core_scsi3_alloc_registration(dev, nacl, deve, isid,
1070 			sa_res_key, all_tg_pt, aptpl);
1071 	if (!pr_reg)
1072 		return -EPERM;
1073 
1074 	__core_scsi3_add_registration(dev, nacl, pr_reg,
1075 			register_type, register_move);
1076 	return 0;
1077 }
1078 
1079 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1080 	struct se_device *dev,
1081 	struct se_node_acl *nacl,
1082 	unsigned char *isid)
1083 {
1084 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1085 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1086 	struct se_portal_group *tpg;
1087 
1088 	spin_lock(&pr_tmpl->registration_lock);
1089 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1090 			&pr_tmpl->registration_list, pr_reg_list) {
1091 		/*
1092 		 * First look for a matching struct se_node_acl
1093 		 */
1094 		if (pr_reg->pr_reg_nacl != nacl)
1095 			continue;
1096 
1097 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1098 		/*
1099 		 * If this registration does NOT contain a fabric provided
1100 		 * ISID, then we have found a match.
1101 		 */
1102 		if (!pr_reg->isid_present_at_reg) {
1103 			/*
1104 			 * Determine if this SCSI device server requires that
1105 			 * SCSI Intiatior TransportID w/ ISIDs is enforced
1106 			 * for fabric modules (iSCSI) requiring them.
1107 			 */
1108 			if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1109 				if (dev->dev_attrib.enforce_pr_isids)
1110 					continue;
1111 			}
1112 			atomic_inc(&pr_reg->pr_res_holders);
1113 			smp_mb__after_atomic_inc();
1114 			spin_unlock(&pr_tmpl->registration_lock);
1115 			return pr_reg;
1116 		}
1117 		/*
1118 		 * If the *pr_reg contains a fabric defined ISID for multi-value
1119 		 * SCSI Initiator Port TransportIDs, then we expect a valid
1120 		 * matching ISID to be provided by the local SCSI Initiator Port.
1121 		 */
1122 		if (!isid)
1123 			continue;
1124 		if (strcmp(isid, pr_reg->pr_reg_isid))
1125 			continue;
1126 
1127 		atomic_inc(&pr_reg->pr_res_holders);
1128 		smp_mb__after_atomic_inc();
1129 		spin_unlock(&pr_tmpl->registration_lock);
1130 		return pr_reg;
1131 	}
1132 	spin_unlock(&pr_tmpl->registration_lock);
1133 
1134 	return NULL;
1135 }
1136 
1137 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1138 	struct se_device *dev,
1139 	struct se_node_acl *nacl,
1140 	struct se_session *sess)
1141 {
1142 	struct se_portal_group *tpg = nacl->se_tpg;
1143 	unsigned char buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
1144 
1145 	if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1146 		memset(&buf[0], 0, PR_REG_ISID_LEN);
1147 		tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1148 					PR_REG_ISID_LEN);
1149 		isid_ptr = &buf[0];
1150 	}
1151 
1152 	return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1153 }
1154 
1155 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1156 {
1157 	atomic_dec(&pr_reg->pr_res_holders);
1158 	smp_mb__after_atomic_dec();
1159 }
1160 
1161 static int core_scsi3_check_implicit_release(
1162 	struct se_device *dev,
1163 	struct t10_pr_registration *pr_reg)
1164 {
1165 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1166 	struct t10_pr_registration *pr_res_holder;
1167 	int ret = 0;
1168 
1169 	spin_lock(&dev->dev_reservation_lock);
1170 	pr_res_holder = dev->dev_pr_res_holder;
1171 	if (!pr_res_holder) {
1172 		spin_unlock(&dev->dev_reservation_lock);
1173 		return ret;
1174 	}
1175 	if (pr_res_holder == pr_reg) {
1176 		/*
1177 		 * Perform an implicit RELEASE if the registration that
1178 		 * is being released is holding the reservation.
1179 		 *
1180 		 * From spc4r17, section 5.7.11.1:
1181 		 *
1182 		 * e) If the I_T nexus is the persistent reservation holder
1183 		 *    and the persistent reservation is not an all registrants
1184 		 *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1185 		 *    service action or REGISTER AND  IGNORE EXISTING KEY
1186 		 *    service action with the SERVICE ACTION RESERVATION KEY
1187 		 *    field set to zero (see 5.7.11.3).
1188 		 */
1189 		__core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0);
1190 		ret = 1;
1191 		/*
1192 		 * For 'All Registrants' reservation types, all existing
1193 		 * registrations are still processed as reservation holders
1194 		 * in core_scsi3_pr_seq_non_holder() after the initial
1195 		 * reservation holder is implicitly released here.
1196 		 */
1197 	} else if (pr_reg->pr_reg_all_tg_pt &&
1198 		  (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1199 			  pr_reg->pr_reg_nacl->initiatorname)) &&
1200 		  (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1201 		pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1202 			" UNREGISTER while existing reservation with matching"
1203 			" key 0x%016Lx is present from another SCSI Initiator"
1204 			" Port\n", pr_reg->pr_res_key);
1205 		ret = -EPERM;
1206 	}
1207 	spin_unlock(&dev->dev_reservation_lock);
1208 
1209 	return ret;
1210 }
1211 
1212 /*
1213  * Called with struct t10_reservation->registration_lock held.
1214  */
1215 static void __core_scsi3_free_registration(
1216 	struct se_device *dev,
1217 	struct t10_pr_registration *pr_reg,
1218 	struct list_head *preempt_and_abort_list,
1219 	int dec_holders)
1220 {
1221 	struct target_core_fabric_ops *tfo =
1222 			pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1223 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1224 	char i_buf[PR_REG_ISID_ID_LEN];
1225 
1226 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1227 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1228 
1229 	pr_reg->pr_reg_deve->def_pr_registered = 0;
1230 	pr_reg->pr_reg_deve->pr_res_key = 0;
1231 	list_del(&pr_reg->pr_reg_list);
1232 	/*
1233 	 * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1234 	 * so call core_scsi3_put_pr_reg() to decrement our reference.
1235 	 */
1236 	if (dec_holders)
1237 		core_scsi3_put_pr_reg(pr_reg);
1238 	/*
1239 	 * Wait until all reference from any other I_T nexuses for this
1240 	 * *pr_reg have been released.  Because list_del() is called above,
1241 	 * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1242 	 * count back to zero, and we release *pr_reg.
1243 	 */
1244 	while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1245 		spin_unlock(&pr_tmpl->registration_lock);
1246 		pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1247 				tfo->get_fabric_name());
1248 		cpu_relax();
1249 		spin_lock(&pr_tmpl->registration_lock);
1250 	}
1251 
1252 	pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1253 		" Node: %s%s\n", tfo->get_fabric_name(),
1254 		pr_reg->pr_reg_nacl->initiatorname,
1255 		i_buf);
1256 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1257 		" Port(s)\n", tfo->get_fabric_name(),
1258 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1259 		dev->transport->name);
1260 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1261 		" 0x%08x\n", tfo->get_fabric_name(), pr_reg->pr_res_key,
1262 		pr_reg->pr_res_generation);
1263 
1264 	if (!preempt_and_abort_list) {
1265 		pr_reg->pr_reg_deve = NULL;
1266 		pr_reg->pr_reg_nacl = NULL;
1267 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1268 		return;
1269 	}
1270 	/*
1271 	 * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1272 	 * are released once the ABORT_TASK_SET has completed..
1273 	 */
1274 	list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1275 }
1276 
1277 void core_scsi3_free_pr_reg_from_nacl(
1278 	struct se_device *dev,
1279 	struct se_node_acl *nacl)
1280 {
1281 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1282 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1283 	/*
1284 	 * If the passed se_node_acl matches the reservation holder,
1285 	 * release the reservation.
1286 	 */
1287 	spin_lock(&dev->dev_reservation_lock);
1288 	pr_res_holder = dev->dev_pr_res_holder;
1289 	if ((pr_res_holder != NULL) &&
1290 	    (pr_res_holder->pr_reg_nacl == nacl))
1291 		__core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0);
1292 	spin_unlock(&dev->dev_reservation_lock);
1293 	/*
1294 	 * Release any registration associated with the struct se_node_acl.
1295 	 */
1296 	spin_lock(&pr_tmpl->registration_lock);
1297 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1298 			&pr_tmpl->registration_list, pr_reg_list) {
1299 
1300 		if (pr_reg->pr_reg_nacl != nacl)
1301 			continue;
1302 
1303 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1304 	}
1305 	spin_unlock(&pr_tmpl->registration_lock);
1306 }
1307 
1308 void core_scsi3_free_all_registrations(
1309 	struct se_device *dev)
1310 {
1311 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1312 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1313 
1314 	spin_lock(&dev->dev_reservation_lock);
1315 	pr_res_holder = dev->dev_pr_res_holder;
1316 	if (pr_res_holder != NULL) {
1317 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1318 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
1319 				pr_res_holder, 0);
1320 	}
1321 	spin_unlock(&dev->dev_reservation_lock);
1322 
1323 	spin_lock(&pr_tmpl->registration_lock);
1324 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1325 			&pr_tmpl->registration_list, pr_reg_list) {
1326 
1327 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1328 	}
1329 	spin_unlock(&pr_tmpl->registration_lock);
1330 
1331 	spin_lock(&pr_tmpl->aptpl_reg_lock);
1332 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1333 				pr_reg_aptpl_list) {
1334 		list_del(&pr_reg->pr_reg_aptpl_list);
1335 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1336 	}
1337 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
1338 }
1339 
1340 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1341 {
1342 	return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1343 			&tpg->tpg_group.cg_item);
1344 }
1345 
1346 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1347 {
1348 	configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1349 			&tpg->tpg_group.cg_item);
1350 
1351 	atomic_dec(&tpg->tpg_pr_ref_count);
1352 	smp_mb__after_atomic_dec();
1353 }
1354 
1355 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1356 {
1357 	struct se_portal_group *tpg = nacl->se_tpg;
1358 
1359 	if (nacl->dynamic_node_acl)
1360 		return 0;
1361 
1362 	return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1363 			&nacl->acl_group.cg_item);
1364 }
1365 
1366 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1367 {
1368 	struct se_portal_group *tpg = nacl->se_tpg;
1369 
1370 	if (nacl->dynamic_node_acl) {
1371 		atomic_dec(&nacl->acl_pr_ref_count);
1372 		smp_mb__after_atomic_dec();
1373 		return;
1374 	}
1375 
1376 	configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1377 			&nacl->acl_group.cg_item);
1378 
1379 	atomic_dec(&nacl->acl_pr_ref_count);
1380 	smp_mb__after_atomic_dec();
1381 }
1382 
1383 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1384 {
1385 	struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1386 	struct se_node_acl *nacl;
1387 	struct se_portal_group *tpg;
1388 	/*
1389 	 * For nacl->dynamic_node_acl=1
1390 	 */
1391 	if (!lun_acl)
1392 		return 0;
1393 
1394 	nacl = lun_acl->se_lun_nacl;
1395 	tpg = nacl->se_tpg;
1396 
1397 	return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1398 			&lun_acl->se_lun_group.cg_item);
1399 }
1400 
1401 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1402 {
1403 	struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1404 	struct se_node_acl *nacl;
1405 	struct se_portal_group *tpg;
1406 	/*
1407 	 * For nacl->dynamic_node_acl=1
1408 	 */
1409 	if (!lun_acl) {
1410 		atomic_dec(&se_deve->pr_ref_count);
1411 		smp_mb__after_atomic_dec();
1412 		return;
1413 	}
1414 	nacl = lun_acl->se_lun_nacl;
1415 	tpg = nacl->se_tpg;
1416 
1417 	configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1418 			&lun_acl->se_lun_group.cg_item);
1419 
1420 	atomic_dec(&se_deve->pr_ref_count);
1421 	smp_mb__after_atomic_dec();
1422 }
1423 
1424 static sense_reason_t
1425 core_scsi3_decode_spec_i_port(
1426 	struct se_cmd *cmd,
1427 	struct se_portal_group *tpg,
1428 	unsigned char *l_isid,
1429 	u64 sa_res_key,
1430 	int all_tg_pt,
1431 	int aptpl)
1432 {
1433 	struct se_device *dev = cmd->se_dev;
1434 	struct se_port *tmp_port;
1435 	struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1436 	struct se_session *se_sess = cmd->se_sess;
1437 	struct se_node_acl *dest_node_acl = NULL;
1438 	struct se_dev_entry *dest_se_deve = NULL, *local_se_deve;
1439 	struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1440 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1441 	LIST_HEAD(tid_dest_list);
1442 	struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1443 	struct target_core_fabric_ops *tmp_tf_ops;
1444 	unsigned char *buf;
1445 	unsigned char *ptr, *i_str = NULL, proto_ident, tmp_proto_ident;
1446 	char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
1447 	sense_reason_t ret;
1448 	u32 tpdl, tid_len = 0;
1449 	int dest_local_nexus;
1450 	u32 dest_rtpi = 0;
1451 
1452 	memset(dest_iport, 0, 64);
1453 
1454 	local_se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
1455 	/*
1456 	 * Allocate a struct pr_transport_id_holder and setup the
1457 	 * local_node_acl and local_se_deve pointers and add to
1458 	 * struct list_head tid_dest_list for add registration
1459 	 * processing in the loop of tid_dest_list below.
1460 	 */
1461 	tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1462 	if (!tidh_new) {
1463 		pr_err("Unable to allocate tidh_new\n");
1464 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1465 	}
1466 	INIT_LIST_HEAD(&tidh_new->dest_list);
1467 	tidh_new->dest_tpg = tpg;
1468 	tidh_new->dest_node_acl = se_sess->se_node_acl;
1469 	tidh_new->dest_se_deve = local_se_deve;
1470 
1471 	local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1472 				se_sess->se_node_acl, local_se_deve, l_isid,
1473 				sa_res_key, all_tg_pt, aptpl);
1474 	if (!local_pr_reg) {
1475 		kfree(tidh_new);
1476 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1477 	}
1478 	tidh_new->dest_pr_reg = local_pr_reg;
1479 	/*
1480 	 * The local I_T nexus does not hold any configfs dependances,
1481 	 * so we set tid_h->dest_local_nexus=1 to prevent the
1482 	 * configfs_undepend_item() calls in the tid_dest_list loops below.
1483 	 */
1484 	tidh_new->dest_local_nexus = 1;
1485 	list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1486 
1487 	if (cmd->data_length < 28) {
1488 		pr_warn("SPC-PR: Received PR OUT parameter list"
1489 			" length too small: %u\n", cmd->data_length);
1490 		ret = TCM_INVALID_PARAMETER_LIST;
1491 		goto out;
1492 	}
1493 
1494 	buf = transport_kmap_data_sg(cmd);
1495 	if (!buf) {
1496 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1497 		goto out;
1498 	}
1499 
1500 	/*
1501 	 * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1502 	 * first extract TransportID Parameter Data Length, and make sure
1503 	 * the value matches up to the SCSI expected data transfer length.
1504 	 */
1505 	tpdl = (buf[24] & 0xff) << 24;
1506 	tpdl |= (buf[25] & 0xff) << 16;
1507 	tpdl |= (buf[26] & 0xff) << 8;
1508 	tpdl |= buf[27] & 0xff;
1509 
1510 	if ((tpdl + 28) != cmd->data_length) {
1511 		pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1512 			" does not equal CDB data_length: %u\n", tpdl,
1513 			cmd->data_length);
1514 		ret = TCM_INVALID_PARAMETER_LIST;
1515 		goto out_unmap;
1516 	}
1517 	/*
1518 	 * Start processing the received transport IDs using the
1519 	 * receiving I_T Nexus portal's fabric dependent methods to
1520 	 * obtain the SCSI Initiator Port/Device Identifiers.
1521 	 */
1522 	ptr = &buf[28];
1523 
1524 	while (tpdl > 0) {
1525 		proto_ident = (ptr[0] & 0x0f);
1526 		dest_tpg = NULL;
1527 
1528 		spin_lock(&dev->se_port_lock);
1529 		list_for_each_entry(tmp_port, &dev->dev_sep_list, sep_list) {
1530 			tmp_tpg = tmp_port->sep_tpg;
1531 			if (!tmp_tpg)
1532 				continue;
1533 			tmp_tf_ops = tmp_tpg->se_tpg_tfo;
1534 			if (!tmp_tf_ops)
1535 				continue;
1536 			if (!tmp_tf_ops->get_fabric_proto_ident ||
1537 			    !tmp_tf_ops->tpg_parse_pr_out_transport_id)
1538 				continue;
1539 			/*
1540 			 * Look for the matching proto_ident provided by
1541 			 * the received TransportID
1542 			 */
1543 			tmp_proto_ident = tmp_tf_ops->get_fabric_proto_ident(tmp_tpg);
1544 			if (tmp_proto_ident != proto_ident)
1545 				continue;
1546 			dest_rtpi = tmp_port->sep_rtpi;
1547 
1548 			i_str = tmp_tf_ops->tpg_parse_pr_out_transport_id(
1549 					tmp_tpg, (const char *)ptr, &tid_len,
1550 					&iport_ptr);
1551 			if (!i_str)
1552 				continue;
1553 
1554 			atomic_inc(&tmp_tpg->tpg_pr_ref_count);
1555 			smp_mb__after_atomic_inc();
1556 			spin_unlock(&dev->se_port_lock);
1557 
1558 			if (core_scsi3_tpg_depend_item(tmp_tpg)) {
1559 				pr_err(" core_scsi3_tpg_depend_item()"
1560 					" for tmp_tpg\n");
1561 				atomic_dec(&tmp_tpg->tpg_pr_ref_count);
1562 				smp_mb__after_atomic_dec();
1563 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1564 				goto out_unmap;
1565 			}
1566 			/*
1567 			 * Locate the destination initiator ACL to be registered
1568 			 * from the decoded fabric module specific TransportID
1569 			 * at *i_str.
1570 			 */
1571 			spin_lock_irq(&tmp_tpg->acl_node_lock);
1572 			dest_node_acl = __core_tpg_get_initiator_node_acl(
1573 						tmp_tpg, i_str);
1574 			if (dest_node_acl) {
1575 				atomic_inc(&dest_node_acl->acl_pr_ref_count);
1576 				smp_mb__after_atomic_inc();
1577 			}
1578 			spin_unlock_irq(&tmp_tpg->acl_node_lock);
1579 
1580 			if (!dest_node_acl) {
1581 				core_scsi3_tpg_undepend_item(tmp_tpg);
1582 				spin_lock(&dev->se_port_lock);
1583 				continue;
1584 			}
1585 
1586 			if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
1587 				pr_err("configfs_depend_item() failed"
1588 					" for dest_node_acl->acl_group\n");
1589 				atomic_dec(&dest_node_acl->acl_pr_ref_count);
1590 				smp_mb__after_atomic_dec();
1591 				core_scsi3_tpg_undepend_item(tmp_tpg);
1592 				ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1593 				goto out_unmap;
1594 			}
1595 
1596 			dest_tpg = tmp_tpg;
1597 			pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1598 				" %s Port RTPI: %hu\n",
1599 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1600 				dest_node_acl->initiatorname, dest_rtpi);
1601 
1602 			spin_lock(&dev->se_port_lock);
1603 			break;
1604 		}
1605 		spin_unlock(&dev->se_port_lock);
1606 
1607 		if (!dest_tpg) {
1608 			pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1609 					" dest_tpg\n");
1610 			ret = TCM_INVALID_PARAMETER_LIST;
1611 			goto out_unmap;
1612 		}
1613 
1614 		pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1615 			" tid_len: %d for %s + %s\n",
1616 			dest_tpg->se_tpg_tfo->get_fabric_name(), cmd->data_length,
1617 			tpdl, tid_len, i_str, iport_ptr);
1618 
1619 		if (tid_len > tpdl) {
1620 			pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1621 				" %u for Transport ID: %s\n", tid_len, ptr);
1622 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1623 			core_scsi3_tpg_undepend_item(dest_tpg);
1624 			ret = TCM_INVALID_PARAMETER_LIST;
1625 			goto out_unmap;
1626 		}
1627 		/*
1628 		 * Locate the desintation struct se_dev_entry pointer for matching
1629 		 * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1630 		 * Target Port.
1631 		 */
1632 		dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1633 					dest_rtpi);
1634 		if (!dest_se_deve) {
1635 			pr_err("Unable to locate %s dest_se_deve"
1636 				" from destination RTPI: %hu\n",
1637 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1638 				dest_rtpi);
1639 
1640 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1641 			core_scsi3_tpg_undepend_item(dest_tpg);
1642 			ret = TCM_INVALID_PARAMETER_LIST;
1643 			goto out_unmap;
1644 		}
1645 
1646 		if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
1647 			pr_err("core_scsi3_lunacl_depend_item()"
1648 					" failed\n");
1649 			atomic_dec(&dest_se_deve->pr_ref_count);
1650 			smp_mb__after_atomic_dec();
1651 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1652 			core_scsi3_tpg_undepend_item(dest_tpg);
1653 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1654 			goto out_unmap;
1655 		}
1656 
1657 		pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1658 			" dest_se_deve mapped_lun: %u\n",
1659 			dest_tpg->se_tpg_tfo->get_fabric_name(),
1660 			dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1661 
1662 		/*
1663 		 * Skip any TransportIDs that already have a registration for
1664 		 * this target port.
1665 		 */
1666 		pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1667 					iport_ptr);
1668 		if (pr_reg_e) {
1669 			core_scsi3_put_pr_reg(pr_reg_e);
1670 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1671 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1672 			core_scsi3_tpg_undepend_item(dest_tpg);
1673 			ptr += tid_len;
1674 			tpdl -= tid_len;
1675 			tid_len = 0;
1676 			continue;
1677 		}
1678 		/*
1679 		 * Allocate a struct pr_transport_id_holder and setup
1680 		 * the dest_node_acl and dest_se_deve pointers for the
1681 		 * loop below.
1682 		 */
1683 		tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1684 				GFP_KERNEL);
1685 		if (!tidh_new) {
1686 			pr_err("Unable to allocate tidh_new\n");
1687 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1688 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1689 			core_scsi3_tpg_undepend_item(dest_tpg);
1690 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1691 			goto out_unmap;
1692 		}
1693 		INIT_LIST_HEAD(&tidh_new->dest_list);
1694 		tidh_new->dest_tpg = dest_tpg;
1695 		tidh_new->dest_node_acl = dest_node_acl;
1696 		tidh_new->dest_se_deve = dest_se_deve;
1697 
1698 		/*
1699 		 * Allocate, but do NOT add the registration for the
1700 		 * TransportID referenced SCSI Initiator port.  This
1701 		 * done because of the following from spc4r17 in section
1702 		 * 6.14.3 wrt SPEC_I_PT:
1703 		 *
1704 		 * "If a registration fails for any initiator port (e.g., if th
1705 		 * logical unit does not have enough resources available to
1706 		 * hold the registration information), no registrations shall be
1707 		 * made, and the command shall be terminated with
1708 		 * CHECK CONDITION status."
1709 		 *
1710 		 * That means we call __core_scsi3_alloc_registration() here,
1711 		 * and then call __core_scsi3_add_registration() in the
1712 		 * 2nd loop which will never fail.
1713 		 */
1714 		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1715 				dest_node_acl, dest_se_deve, iport_ptr,
1716 				sa_res_key, all_tg_pt, aptpl);
1717 		if (!dest_pr_reg) {
1718 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1719 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1720 			core_scsi3_tpg_undepend_item(dest_tpg);
1721 			kfree(tidh_new);
1722 			ret = TCM_INVALID_PARAMETER_LIST;
1723 			goto out_unmap;
1724 		}
1725 		tidh_new->dest_pr_reg = dest_pr_reg;
1726 		list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1727 
1728 		ptr += tid_len;
1729 		tpdl -= tid_len;
1730 		tid_len = 0;
1731 
1732 	}
1733 
1734 	transport_kunmap_data_sg(cmd);
1735 
1736 	/*
1737 	 * Go ahead and create a registrations from tid_dest_list for the
1738 	 * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1739 	 * and dest_se_deve.
1740 	 *
1741 	 * The SA Reservation Key from the PROUT is set for the
1742 	 * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1743 	 * means that the TransportID Initiator port will be
1744 	 * registered on all of the target ports in the SCSI target device
1745 	 * ALL_TG_PT=0 means the registration will only be for the
1746 	 * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1747 	 * was received.
1748 	 */
1749 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1750 		dest_tpg = tidh->dest_tpg;
1751 		dest_node_acl = tidh->dest_node_acl;
1752 		dest_se_deve = tidh->dest_se_deve;
1753 		dest_pr_reg = tidh->dest_pr_reg;
1754 		dest_local_nexus = tidh->dest_local_nexus;
1755 
1756 		list_del(&tidh->dest_list);
1757 		kfree(tidh);
1758 
1759 		memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1760 		core_pr_dump_initiator_port(dest_pr_reg, i_buf, PR_REG_ISID_ID_LEN);
1761 
1762 		__core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1763 					dest_pr_reg, 0, 0);
1764 
1765 		pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1766 			" registered Transport ID for Node: %s%s Mapped LUN:"
1767 			" %u\n", dest_tpg->se_tpg_tfo->get_fabric_name(),
1768 			dest_node_acl->initiatorname, i_buf, dest_se_deve->mapped_lun);
1769 
1770 		if (dest_local_nexus)
1771 			continue;
1772 
1773 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1774 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1775 		core_scsi3_tpg_undepend_item(dest_tpg);
1776 	}
1777 
1778 	return 0;
1779 out_unmap:
1780 	transport_kunmap_data_sg(cmd);
1781 out:
1782 	/*
1783 	 * For the failure case, release everything from tid_dest_list
1784 	 * including *dest_pr_reg and the configfs dependances..
1785 	 */
1786 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1787 		dest_tpg = tidh->dest_tpg;
1788 		dest_node_acl = tidh->dest_node_acl;
1789 		dest_se_deve = tidh->dest_se_deve;
1790 		dest_pr_reg = tidh->dest_pr_reg;
1791 		dest_local_nexus = tidh->dest_local_nexus;
1792 
1793 		list_del(&tidh->dest_list);
1794 		kfree(tidh);
1795 		/*
1796 		 * Release any extra ALL_TG_PT=1 registrations for
1797 		 * the SPEC_I_PT=1 case.
1798 		 */
1799 		list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1800 				&dest_pr_reg->pr_reg_atp_list,
1801 				pr_reg_atp_mem_list) {
1802 			list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1803 			core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1804 			kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1805 		}
1806 
1807 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1808 
1809 		if (dest_local_nexus)
1810 			continue;
1811 
1812 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1813 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1814 		core_scsi3_tpg_undepend_item(dest_tpg);
1815 	}
1816 	return ret;
1817 }
1818 
1819 static int core_scsi3_update_aptpl_buf(
1820 	struct se_device *dev,
1821 	unsigned char *buf,
1822 	u32 pr_aptpl_buf_len)
1823 {
1824 	struct se_lun *lun;
1825 	struct se_portal_group *tpg;
1826 	struct t10_pr_registration *pr_reg;
1827 	unsigned char tmp[512], isid_buf[32];
1828 	ssize_t len = 0;
1829 	int reg_count = 0;
1830 	int ret = 0;
1831 
1832 	spin_lock(&dev->dev_reservation_lock);
1833 	spin_lock(&dev->t10_pr.registration_lock);
1834 	/*
1835 	 * Walk the registration list..
1836 	 */
1837 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
1838 			pr_reg_list) {
1839 
1840 		tmp[0] = '\0';
1841 		isid_buf[0] = '\0';
1842 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1843 		lun = pr_reg->pr_reg_tg_pt_lun;
1844 		/*
1845 		 * Write out any ISID value to APTPL metadata that was included
1846 		 * in the original registration.
1847 		 */
1848 		if (pr_reg->isid_present_at_reg)
1849 			snprintf(isid_buf, 32, "initiator_sid=%s\n",
1850 					pr_reg->pr_reg_isid);
1851 		/*
1852 		 * Include special metadata if the pr_reg matches the
1853 		 * reservation holder.
1854 		 */
1855 		if (dev->dev_pr_res_holder == pr_reg) {
1856 			snprintf(tmp, 512, "PR_REG_START: %d"
1857 				"\ninitiator_fabric=%s\n"
1858 				"initiator_node=%s\n%s"
1859 				"sa_res_key=%llu\n"
1860 				"res_holder=1\nres_type=%02x\n"
1861 				"res_scope=%02x\nres_all_tg_pt=%d\n"
1862 				"mapped_lun=%u\n", reg_count,
1863 				tpg->se_tpg_tfo->get_fabric_name(),
1864 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1865 				pr_reg->pr_res_key, pr_reg->pr_res_type,
1866 				pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1867 				pr_reg->pr_res_mapped_lun);
1868 		} else {
1869 			snprintf(tmp, 512, "PR_REG_START: %d\n"
1870 				"initiator_fabric=%s\ninitiator_node=%s\n%s"
1871 				"sa_res_key=%llu\nres_holder=0\n"
1872 				"res_all_tg_pt=%d\nmapped_lun=%u\n",
1873 				reg_count, tpg->se_tpg_tfo->get_fabric_name(),
1874 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1875 				pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1876 				pr_reg->pr_res_mapped_lun);
1877 		}
1878 
1879 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1880 			pr_err("Unable to update renaming"
1881 				" APTPL metadata\n");
1882 			ret = -EMSGSIZE;
1883 			goto out;
1884 		}
1885 		len += sprintf(buf+len, "%s", tmp);
1886 
1887 		/*
1888 		 * Include information about the associated SCSI target port.
1889 		 */
1890 		snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1891 			"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%u\nPR_REG_END:"
1892 			" %d\n", tpg->se_tpg_tfo->get_fabric_name(),
1893 			tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1894 			tpg->se_tpg_tfo->tpg_get_tag(tpg),
1895 			lun->lun_sep->sep_rtpi, lun->unpacked_lun, reg_count);
1896 
1897 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1898 			pr_err("Unable to update renaming"
1899 				" APTPL metadata\n");
1900 			ret = -EMSGSIZE;
1901 			goto out;
1902 		}
1903 		len += sprintf(buf+len, "%s", tmp);
1904 		reg_count++;
1905 	}
1906 
1907 	if (!reg_count)
1908 		len += sprintf(buf+len, "No Registrations or Reservations");
1909 
1910 out:
1911 	spin_unlock(&dev->t10_pr.registration_lock);
1912 	spin_unlock(&dev->dev_reservation_lock);
1913 
1914 	return ret;
1915 }
1916 
1917 static int __core_scsi3_write_aptpl_to_file(
1918 	struct se_device *dev,
1919 	unsigned char *buf)
1920 {
1921 	struct t10_wwn *wwn = &dev->t10_wwn;
1922 	struct file *file;
1923 	int flags = O_RDWR | O_CREAT | O_TRUNC;
1924 	char path[512];
1925 	u32 pr_aptpl_buf_len;
1926 	int ret;
1927 
1928 	memset(path, 0, 512);
1929 
1930 	if (strlen(&wwn->unit_serial[0]) >= 512) {
1931 		pr_err("WWN value for struct se_device does not fit"
1932 			" into path buffer\n");
1933 		return -EMSGSIZE;
1934 	}
1935 
1936 	snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
1937 	file = filp_open(path, flags, 0600);
1938 	if (IS_ERR(file)) {
1939 		pr_err("filp_open(%s) for APTPL metadata"
1940 			" failed\n", path);
1941 		return PTR_ERR(file);
1942 	}
1943 
1944 	pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
1945 
1946 	ret = kernel_write(file, buf, pr_aptpl_buf_len, 0);
1947 
1948 	if (ret < 0)
1949 		pr_debug("Error writing APTPL metadata file: %s\n", path);
1950 	fput(file);
1951 
1952 	return (ret < 0) ? -EIO : 0;
1953 }
1954 
1955 /*
1956  * Clear the APTPL metadata if APTPL has been disabled, otherwise
1957  * write out the updated metadata to struct file for this SCSI device.
1958  */
1959 static sense_reason_t core_scsi3_update_and_write_aptpl(struct se_device *dev, bool aptpl)
1960 {
1961 	unsigned char *buf;
1962 	int rc;
1963 
1964 	if (!aptpl) {
1965 		char *null_buf = "No Registrations or Reservations\n";
1966 
1967 		rc = __core_scsi3_write_aptpl_to_file(dev, null_buf);
1968 		dev->t10_pr.pr_aptpl_active = 0;
1969 		pr_debug("SPC-3 PR: Set APTPL Bit Deactivated\n");
1970 
1971 		if (rc)
1972 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1973 
1974 		return 0;
1975 	}
1976 
1977 	buf = kzalloc(PR_APTPL_BUF_LEN, GFP_KERNEL);
1978 	if (!buf)
1979 		return TCM_OUT_OF_RESOURCES;
1980 
1981 	rc = core_scsi3_update_aptpl_buf(dev, buf, PR_APTPL_BUF_LEN);
1982 	if (rc < 0) {
1983 		kfree(buf);
1984 		return TCM_OUT_OF_RESOURCES;
1985 	}
1986 
1987 	rc = __core_scsi3_write_aptpl_to_file(dev, buf);
1988 	if (rc != 0) {
1989 		pr_err("SPC-3 PR: Could not update APTPL\n");
1990 		kfree(buf);
1991 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1992 	}
1993 	dev->t10_pr.pr_aptpl_active = 1;
1994 	kfree(buf);
1995 	pr_debug("SPC-3 PR: Set APTPL Bit Activated\n");
1996 	return 0;
1997 }
1998 
1999 static sense_reason_t
2000 core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
2001 		bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type)
2002 {
2003 	struct se_session *se_sess = cmd->se_sess;
2004 	struct se_device *dev = cmd->se_dev;
2005 	struct se_dev_entry *se_deve;
2006 	struct se_lun *se_lun = cmd->se_lun;
2007 	struct se_portal_group *se_tpg;
2008 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp;
2009 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2010 	unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2011 	sense_reason_t ret = TCM_NO_SENSE;
2012 	int pr_holder = 0;
2013 
2014 	if (!se_sess || !se_lun) {
2015 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2016 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2017 	}
2018 	se_tpg = se_sess->se_tpg;
2019 	se_deve = se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2020 
2021 	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2022 		memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2023 		se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2024 				PR_REG_ISID_LEN);
2025 		isid_ptr = &isid_buf[0];
2026 	}
2027 	/*
2028 	 * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2029 	 */
2030 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2031 	if (!pr_reg) {
2032 		if (res_key) {
2033 			pr_warn("SPC-3 PR: Reservation Key non-zero"
2034 				" for SA REGISTER, returning CONFLICT\n");
2035 			return TCM_RESERVATION_CONFLICT;
2036 		}
2037 		/*
2038 		 * Do nothing but return GOOD status.
2039 		 */
2040 		if (!sa_res_key)
2041 			return 0;
2042 
2043 		if (!spec_i_pt) {
2044 			/*
2045 			 * Perform the Service Action REGISTER on the Initiator
2046 			 * Port Endpoint that the PRO was received from on the
2047 			 * Logical Unit of the SCSI device server.
2048 			 */
2049 			if (core_scsi3_alloc_registration(cmd->se_dev,
2050 					se_sess->se_node_acl, se_deve, isid_ptr,
2051 					sa_res_key, all_tg_pt, aptpl,
2052 					register_type, 0)) {
2053 				pr_err("Unable to allocate"
2054 					" struct t10_pr_registration\n");
2055 				return TCM_INVALID_PARAMETER_LIST;
2056 			}
2057 		} else {
2058 			/*
2059 			 * Register both the Initiator port that received
2060 			 * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2061 			 * TransportID from Parameter list and loop through
2062 			 * fabric dependent parameter list while calling
2063 			 * logic from of core_scsi3_alloc_registration() for
2064 			 * each TransportID provided SCSI Initiator Port/Device
2065 			 */
2066 			ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2067 					isid_ptr, sa_res_key, all_tg_pt, aptpl);
2068 			if (ret != 0)
2069 				return ret;
2070 		}
2071 
2072 		return core_scsi3_update_and_write_aptpl(dev, aptpl);
2073 	}
2074 
2075 	/* ok, existing registration */
2076 
2077 	if ((register_type == REGISTER) && (res_key != pr_reg->pr_res_key)) {
2078 		pr_err("SPC-3 PR REGISTER: Received"
2079 		       " res_key: 0x%016Lx does not match"
2080 		       " existing SA REGISTER res_key:"
2081 		       " 0x%016Lx\n", res_key,
2082 		       pr_reg->pr_res_key);
2083 		ret = TCM_RESERVATION_CONFLICT;
2084 		goto out;
2085 	}
2086 
2087 	if (spec_i_pt) {
2088 		pr_err("SPC-3 PR REGISTER: SPEC_I_PT"
2089 			" set on a registered nexus\n");
2090 		ret = TCM_INVALID_PARAMETER_LIST;
2091 		goto out;
2092 	}
2093 
2094 	/*
2095 	 * An existing ALL_TG_PT=1 registration being released
2096 	 * must also set ALL_TG_PT=1 in the incoming PROUT.
2097 	 */
2098 	if (pr_reg->pr_reg_all_tg_pt && !all_tg_pt) {
2099 		pr_err("SPC-3 PR REGISTER: ALL_TG_PT=1"
2100 			" registration exists, but ALL_TG_PT=1 bit not"
2101 			" present in received PROUT\n");
2102 		ret = TCM_INVALID_CDB_FIELD;
2103 		goto out;
2104 	}
2105 
2106 	/*
2107 	 * sa_res_key=1 Change Reservation Key for registered I_T Nexus.
2108 	 */
2109 	if (sa_res_key) {
2110 		/*
2111 		 * Increment PRgeneration counter for struct se_device"
2112 		 * upon a successful REGISTER, see spc4r17 section 6.3.2
2113 		 * READ_KEYS service action.
2114 		 */
2115 		pr_reg->pr_res_generation = core_scsi3_pr_generation(cmd->se_dev);
2116 		pr_reg->pr_res_key = sa_res_key;
2117 		pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2118 			 " Key for %s to: 0x%016Lx PRgeneration:"
2119 			 " 0x%08x\n", cmd->se_tfo->get_fabric_name(),
2120 			 (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ? "_AND_IGNORE_EXISTING_KEY" : "",
2121 			 pr_reg->pr_reg_nacl->initiatorname,
2122 			 pr_reg->pr_res_key, pr_reg->pr_res_generation);
2123 
2124 	} else {
2125 		/*
2126 		 * sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
2127 		 */
2128 		pr_holder = core_scsi3_check_implicit_release(
2129 				cmd->se_dev, pr_reg);
2130 		if (pr_holder < 0) {
2131 			ret = TCM_RESERVATION_CONFLICT;
2132 			goto out;
2133 		}
2134 
2135 		spin_lock(&pr_tmpl->registration_lock);
2136 		/*
2137 		 * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2138 		 * and matching pr_res_key.
2139 		 */
2140 		if (pr_reg->pr_reg_all_tg_pt) {
2141 			list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2142 					&pr_tmpl->registration_list,
2143 					pr_reg_list) {
2144 
2145 				if (!pr_reg_p->pr_reg_all_tg_pt)
2146 					continue;
2147 				if (pr_reg_p->pr_res_key != res_key)
2148 					continue;
2149 				if (pr_reg == pr_reg_p)
2150 					continue;
2151 				if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2152 					   pr_reg_p->pr_reg_nacl->initiatorname))
2153 					continue;
2154 
2155 				__core_scsi3_free_registration(dev,
2156 						pr_reg_p, NULL, 0);
2157 			}
2158 		}
2159 
2160 		/*
2161 		 * Release the calling I_T Nexus registration now..
2162 		 */
2163 		__core_scsi3_free_registration(cmd->se_dev, pr_reg, NULL, 1);
2164 
2165 		/*
2166 		 * From spc4r17, section 5.7.11.3 Unregistering
2167 		 *
2168 		 * If the persistent reservation is a registrants only
2169 		 * type, the device server shall establish a unit
2170 		 * attention condition for the initiator port associated
2171 		 * with every registered I_T nexus except for the I_T
2172 		 * nexus on which the PERSISTENT RESERVE OUT command was
2173 		 * received, with the additional sense code set to
2174 		 * RESERVATIONS RELEASED.
2175 		 */
2176 		if (pr_holder &&
2177 		    (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY ||
2178 		     pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY)) {
2179 			list_for_each_entry(pr_reg_p,
2180 					&pr_tmpl->registration_list,
2181 					pr_reg_list) {
2182 
2183 				core_scsi3_ua_allocate(
2184 					pr_reg_p->pr_reg_nacl,
2185 					pr_reg_p->pr_res_mapped_lun,
2186 					0x2A,
2187 					ASCQ_2AH_RESERVATIONS_RELEASED);
2188 			}
2189 		}
2190 
2191 		spin_unlock(&pr_tmpl->registration_lock);
2192 	}
2193 
2194 	ret = core_scsi3_update_and_write_aptpl(dev, aptpl);
2195 
2196 out:
2197 	core_scsi3_put_pr_reg(pr_reg);
2198 	return ret;
2199 }
2200 
2201 unsigned char *core_scsi3_pr_dump_type(int type)
2202 {
2203 	switch (type) {
2204 	case PR_TYPE_WRITE_EXCLUSIVE:
2205 		return "Write Exclusive Access";
2206 	case PR_TYPE_EXCLUSIVE_ACCESS:
2207 		return "Exclusive Access";
2208 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2209 		return "Write Exclusive Access, Registrants Only";
2210 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2211 		return "Exclusive Access, Registrants Only";
2212 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2213 		return "Write Exclusive Access, All Registrants";
2214 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2215 		return "Exclusive Access, All Registrants";
2216 	default:
2217 		break;
2218 	}
2219 
2220 	return "Unknown SPC-3 PR Type";
2221 }
2222 
2223 static sense_reason_t
2224 core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
2225 {
2226 	struct se_device *dev = cmd->se_dev;
2227 	struct se_session *se_sess = cmd->se_sess;
2228 	struct se_lun *se_lun = cmd->se_lun;
2229 	struct t10_pr_registration *pr_reg, *pr_res_holder;
2230 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2231 	char i_buf[PR_REG_ISID_ID_LEN];
2232 	sense_reason_t ret;
2233 
2234 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2235 
2236 	if (!se_sess || !se_lun) {
2237 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2238 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2239 	}
2240 	/*
2241 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2242 	 */
2243 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2244 				se_sess);
2245 	if (!pr_reg) {
2246 		pr_err("SPC-3 PR: Unable to locate"
2247 			" PR_REGISTERED *pr_reg for RESERVE\n");
2248 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2249 	}
2250 	/*
2251 	 * From spc4r17 Section 5.7.9: Reserving:
2252 	 *
2253 	 * An application client creates a persistent reservation by issuing
2254 	 * a PERSISTENT RESERVE OUT command with RESERVE service action through
2255 	 * a registered I_T nexus with the following parameters:
2256 	 *    a) RESERVATION KEY set to the value of the reservation key that is
2257 	 * 	 registered with the logical unit for the I_T nexus; and
2258 	 */
2259 	if (res_key != pr_reg->pr_res_key) {
2260 		pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2261 			" does not match existing SA REGISTER res_key:"
2262 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2263 		ret = TCM_RESERVATION_CONFLICT;
2264 		goto out_put_pr_reg;
2265 	}
2266 	/*
2267 	 * From spc4r17 Section 5.7.9: Reserving:
2268 	 *
2269 	 * From above:
2270 	 *  b) TYPE field and SCOPE field set to the persistent reservation
2271 	 *     being created.
2272 	 *
2273 	 * Only one persistent reservation is allowed at a time per logical unit
2274 	 * and that persistent reservation has a scope of LU_SCOPE.
2275 	 */
2276 	if (scope != PR_SCOPE_LU_SCOPE) {
2277 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2278 		ret = TCM_INVALID_PARAMETER_LIST;
2279 		goto out_put_pr_reg;
2280 	}
2281 	/*
2282 	 * See if we have an existing PR reservation holder pointer at
2283 	 * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2284 	 * *pr_res_holder.
2285 	 */
2286 	spin_lock(&dev->dev_reservation_lock);
2287 	pr_res_holder = dev->dev_pr_res_holder;
2288 	if (pr_res_holder) {
2289 		/*
2290 		 * From spc4r17 Section 5.7.9: Reserving:
2291 		 *
2292 		 * If the device server receives a PERSISTENT RESERVE OUT
2293 		 * command from an I_T nexus other than a persistent reservation
2294 		 * holder (see 5.7.10) that attempts to create a persistent
2295 		 * reservation when a persistent reservation already exists for
2296 		 * the logical unit, then the command shall be completed with
2297 		 * RESERVATION CONFLICT status.
2298 		 */
2299 		if (pr_res_holder != pr_reg) {
2300 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2301 			pr_err("SPC-3 PR: Attempted RESERVE from"
2302 				" [%s]: %s while reservation already held by"
2303 				" [%s]: %s, returning RESERVATION_CONFLICT\n",
2304 				cmd->se_tfo->get_fabric_name(),
2305 				se_sess->se_node_acl->initiatorname,
2306 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2307 				pr_res_holder->pr_reg_nacl->initiatorname);
2308 
2309 			spin_unlock(&dev->dev_reservation_lock);
2310 			ret = TCM_RESERVATION_CONFLICT;
2311 			goto out_put_pr_reg;
2312 		}
2313 		/*
2314 		 * From spc4r17 Section 5.7.9: Reserving:
2315 		 *
2316 		 * If a persistent reservation holder attempts to modify the
2317 		 * type or scope of an existing persistent reservation, the
2318 		 * command shall be completed with RESERVATION CONFLICT status.
2319 		 */
2320 		if ((pr_res_holder->pr_res_type != type) ||
2321 		    (pr_res_holder->pr_res_scope != scope)) {
2322 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2323 			pr_err("SPC-3 PR: Attempted RESERVE from"
2324 				" [%s]: %s trying to change TYPE and/or SCOPE,"
2325 				" while reservation already held by [%s]: %s,"
2326 				" returning RESERVATION_CONFLICT\n",
2327 				cmd->se_tfo->get_fabric_name(),
2328 				se_sess->se_node_acl->initiatorname,
2329 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2330 				pr_res_holder->pr_reg_nacl->initiatorname);
2331 
2332 			spin_unlock(&dev->dev_reservation_lock);
2333 			ret = TCM_RESERVATION_CONFLICT;
2334 			goto out_put_pr_reg;
2335 		}
2336 		/*
2337 		 * From spc4r17 Section 5.7.9: Reserving:
2338 		 *
2339 		 * If the device server receives a PERSISTENT RESERVE OUT
2340 		 * command with RESERVE service action where the TYPE field and
2341 		 * the SCOPE field contain the same values as the existing type
2342 		 * and scope from a persistent reservation holder, it shall not
2343 		 * make any change to the existing persistent reservation and
2344 		 * shall completethe command with GOOD status.
2345 		 */
2346 		spin_unlock(&dev->dev_reservation_lock);
2347 		ret = 0;
2348 		goto out_put_pr_reg;
2349 	}
2350 	/*
2351 	 * Otherwise, our *pr_reg becomes the PR reservation holder for said
2352 	 * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2353 	 */
2354 	pr_reg->pr_res_scope = scope;
2355 	pr_reg->pr_res_type = type;
2356 	pr_reg->pr_res_holder = 1;
2357 	dev->dev_pr_res_holder = pr_reg;
2358 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2359 
2360 	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2361 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2362 		cmd->se_tfo->get_fabric_name(), core_scsi3_pr_dump_type(type),
2363 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2364 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2365 			cmd->se_tfo->get_fabric_name(),
2366 			se_sess->se_node_acl->initiatorname,
2367 			i_buf);
2368 	spin_unlock(&dev->dev_reservation_lock);
2369 
2370 	if (pr_tmpl->pr_aptpl_active)
2371 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2372 
2373 	ret = 0;
2374 out_put_pr_reg:
2375 	core_scsi3_put_pr_reg(pr_reg);
2376 	return ret;
2377 }
2378 
2379 static sense_reason_t
2380 core_scsi3_emulate_pro_reserve(struct se_cmd *cmd, int type, int scope,
2381 		u64 res_key)
2382 {
2383 	switch (type) {
2384 	case PR_TYPE_WRITE_EXCLUSIVE:
2385 	case PR_TYPE_EXCLUSIVE_ACCESS:
2386 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2387 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2388 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2389 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2390 		return core_scsi3_pro_reserve(cmd, type, scope, res_key);
2391 	default:
2392 		pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2393 			" 0x%02x\n", type);
2394 		return TCM_INVALID_CDB_FIELD;
2395 	}
2396 }
2397 
2398 /*
2399  * Called with struct se_device->dev_reservation_lock held.
2400  */
2401 static void __core_scsi3_complete_pro_release(
2402 	struct se_device *dev,
2403 	struct se_node_acl *se_nacl,
2404 	struct t10_pr_registration *pr_reg,
2405 	int explicit)
2406 {
2407 	struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2408 	char i_buf[PR_REG_ISID_ID_LEN];
2409 
2410 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2411 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2412 	/*
2413 	 * Go ahead and release the current PR reservation holder.
2414 	 */
2415 	dev->dev_pr_res_holder = NULL;
2416 
2417 	pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2418 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2419 		tfo->get_fabric_name(), (explicit) ? "explicit" : "implicit",
2420 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
2421 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2422 	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2423 		tfo->get_fabric_name(), se_nacl->initiatorname,
2424 		i_buf);
2425 	/*
2426 	 * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2427 	 */
2428 	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2429 }
2430 
2431 static sense_reason_t
2432 core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
2433 		u64 res_key)
2434 {
2435 	struct se_device *dev = cmd->se_dev;
2436 	struct se_session *se_sess = cmd->se_sess;
2437 	struct se_lun *se_lun = cmd->se_lun;
2438 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2439 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2440 	int all_reg = 0;
2441 	sense_reason_t ret = 0;
2442 
2443 	if (!se_sess || !se_lun) {
2444 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2445 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2446 	}
2447 	/*
2448 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2449 	 */
2450 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2451 	if (!pr_reg) {
2452 		pr_err("SPC-3 PR: Unable to locate"
2453 			" PR_REGISTERED *pr_reg for RELEASE\n");
2454 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2455 	}
2456 	/*
2457 	 * From spc4r17 Section 5.7.11.2 Releasing:
2458 	 *
2459 	 * If there is no persistent reservation or in response to a persistent
2460 	 * reservation release request from a registered I_T nexus that is not a
2461 	 * persistent reservation holder (see 5.7.10), the device server shall
2462 	 * do the following:
2463 	 *
2464 	 *     a) Not release the persistent reservation, if any;
2465 	 *     b) Not remove any registrations; and
2466 	 *     c) Complete the command with GOOD status.
2467 	 */
2468 	spin_lock(&dev->dev_reservation_lock);
2469 	pr_res_holder = dev->dev_pr_res_holder;
2470 	if (!pr_res_holder) {
2471 		/*
2472 		 * No persistent reservation, return GOOD status.
2473 		 */
2474 		spin_unlock(&dev->dev_reservation_lock);
2475 		goto out_put_pr_reg;
2476 	}
2477 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2478 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
2479 		all_reg = 1;
2480 
2481 	if ((all_reg == 0) && (pr_res_holder != pr_reg)) {
2482 		/*
2483 		 * Non 'All Registrants' PR Type cases..
2484 		 * Release request from a registered I_T nexus that is not a
2485 		 * persistent reservation holder. return GOOD status.
2486 		 */
2487 		spin_unlock(&dev->dev_reservation_lock);
2488 		goto out_put_pr_reg;
2489 	}
2490 
2491 	/*
2492 	 * From spc4r17 Section 5.7.11.2 Releasing:
2493 	 *
2494 	 * Only the persistent reservation holder (see 5.7.10) is allowed to
2495 	 * release a persistent reservation.
2496 	 *
2497 	 * An application client releases the persistent reservation by issuing
2498 	 * a PERSISTENT RESERVE OUT command with RELEASE service action through
2499 	 * an I_T nexus that is a persistent reservation holder with the
2500 	 * following parameters:
2501 	 *
2502 	 *     a) RESERVATION KEY field set to the value of the reservation key
2503 	 *	  that is registered with the logical unit for the I_T nexus;
2504 	 */
2505 	if (res_key != pr_reg->pr_res_key) {
2506 		pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2507 			" does not match existing SA REGISTER res_key:"
2508 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2509 		spin_unlock(&dev->dev_reservation_lock);
2510 		ret = TCM_RESERVATION_CONFLICT;
2511 		goto out_put_pr_reg;
2512 	}
2513 	/*
2514 	 * From spc4r17 Section 5.7.11.2 Releasing and above:
2515 	 *
2516 	 * b) TYPE field and SCOPE field set to match the persistent
2517 	 *    reservation being released.
2518 	 */
2519 	if ((pr_res_holder->pr_res_type != type) ||
2520 	    (pr_res_holder->pr_res_scope != scope)) {
2521 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2522 		pr_err("SPC-3 PR RELEASE: Attempted to release"
2523 			" reservation from [%s]: %s with different TYPE "
2524 			"and/or SCOPE  while reservation already held by"
2525 			" [%s]: %s, returning RESERVATION_CONFLICT\n",
2526 			cmd->se_tfo->get_fabric_name(),
2527 			se_sess->se_node_acl->initiatorname,
2528 			pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2529 			pr_res_holder->pr_reg_nacl->initiatorname);
2530 
2531 		spin_unlock(&dev->dev_reservation_lock);
2532 		ret = TCM_RESERVATION_CONFLICT;
2533 		goto out_put_pr_reg;
2534 	}
2535 	/*
2536 	 * In response to a persistent reservation release request from the
2537 	 * persistent reservation holder the device server shall perform a
2538 	 * release by doing the following as an uninterrupted series of actions:
2539 	 * a) Release the persistent reservation;
2540 	 * b) Not remove any registration(s);
2541 	 * c) If the released persistent reservation is a registrants only type
2542 	 * or all registrants type persistent reservation,
2543 	 *    the device server shall establish a unit attention condition for
2544 	 *    the initiator port associated with every regis-
2545 	 *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2546 	 *    RESERVE OUT command with RELEASE service action was received,
2547 	 *    with the additional sense code set to RESERVATIONS RELEASED; and
2548 	 * d) If the persistent reservation is of any other type, the device
2549 	 *    server shall not establish a unit attention condition.
2550 	 */
2551 	__core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2552 			pr_reg, 1);
2553 
2554 	spin_unlock(&dev->dev_reservation_lock);
2555 
2556 	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2557 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2558 	    (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2559 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2560 		/*
2561 		 * If no UNIT ATTENTION conditions will be established for
2562 		 * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2563 		 * go ahead and check for APTPL=1 update+write below
2564 		 */
2565 		goto write_aptpl;
2566 	}
2567 
2568 	spin_lock(&pr_tmpl->registration_lock);
2569 	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2570 			pr_reg_list) {
2571 		/*
2572 		 * Do not establish a UNIT ATTENTION condition
2573 		 * for the calling I_T Nexus
2574 		 */
2575 		if (pr_reg_p == pr_reg)
2576 			continue;
2577 
2578 		core_scsi3_ua_allocate(pr_reg_p->pr_reg_nacl,
2579 				pr_reg_p->pr_res_mapped_lun,
2580 				0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2581 	}
2582 	spin_unlock(&pr_tmpl->registration_lock);
2583 
2584 write_aptpl:
2585 	if (pr_tmpl->pr_aptpl_active)
2586 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2587 
2588 out_put_pr_reg:
2589 	core_scsi3_put_pr_reg(pr_reg);
2590 	return ret;
2591 }
2592 
2593 static sense_reason_t
2594 core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
2595 {
2596 	struct se_device *dev = cmd->se_dev;
2597 	struct se_node_acl *pr_reg_nacl;
2598 	struct se_session *se_sess = cmd->se_sess;
2599 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2600 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2601 	u32 pr_res_mapped_lun = 0;
2602 	int calling_it_nexus = 0;
2603 	/*
2604 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2605 	 */
2606 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2607 			se_sess->se_node_acl, se_sess);
2608 	if (!pr_reg_n) {
2609 		pr_err("SPC-3 PR: Unable to locate"
2610 			" PR_REGISTERED *pr_reg for CLEAR\n");
2611 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2612 	}
2613 	/*
2614 	 * From spc4r17 section 5.7.11.6, Clearing:
2615 	 *
2616 	 * Any application client may release the persistent reservation and
2617 	 * remove all registrations from a device server by issuing a
2618 	 * PERSISTENT RESERVE OUT command with CLEAR service action through a
2619 	 * registered I_T nexus with the following parameter:
2620 	 *
2621 	 *	a) RESERVATION KEY field set to the value of the reservation key
2622 	 * 	   that is registered with the logical unit for the I_T nexus.
2623 	 */
2624 	if (res_key != pr_reg_n->pr_res_key) {
2625 		pr_err("SPC-3 PR REGISTER: Received"
2626 			" res_key: 0x%016Lx does not match"
2627 			" existing SA REGISTER res_key:"
2628 			" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2629 		core_scsi3_put_pr_reg(pr_reg_n);
2630 		return TCM_RESERVATION_CONFLICT;
2631 	}
2632 	/*
2633 	 * a) Release the persistent reservation, if any;
2634 	 */
2635 	spin_lock(&dev->dev_reservation_lock);
2636 	pr_res_holder = dev->dev_pr_res_holder;
2637 	if (pr_res_holder) {
2638 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2639 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
2640 			pr_res_holder, 0);
2641 	}
2642 	spin_unlock(&dev->dev_reservation_lock);
2643 	/*
2644 	 * b) Remove all registration(s) (see spc4r17 5.7.7);
2645 	 */
2646 	spin_lock(&pr_tmpl->registration_lock);
2647 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2648 			&pr_tmpl->registration_list, pr_reg_list) {
2649 
2650 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2651 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2652 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2653 		__core_scsi3_free_registration(dev, pr_reg, NULL,
2654 					calling_it_nexus);
2655 		/*
2656 		 * e) Establish a unit attention condition for the initiator
2657 		 *    port associated with every registered I_T nexus other
2658 		 *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2659 		 *    command with CLEAR service action was received, with the
2660 		 *    additional sense code set to RESERVATIONS PREEMPTED.
2661 		 */
2662 		if (!calling_it_nexus)
2663 			core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun,
2664 				0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2665 	}
2666 	spin_unlock(&pr_tmpl->registration_lock);
2667 
2668 	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2669 		cmd->se_tfo->get_fabric_name());
2670 
2671 	core_scsi3_update_and_write_aptpl(cmd->se_dev, false);
2672 
2673 	core_scsi3_pr_generation(dev);
2674 	return 0;
2675 }
2676 
2677 /*
2678  * Called with struct se_device->dev_reservation_lock held.
2679  */
2680 static void __core_scsi3_complete_pro_preempt(
2681 	struct se_device *dev,
2682 	struct t10_pr_registration *pr_reg,
2683 	struct list_head *preempt_and_abort_list,
2684 	int type,
2685 	int scope,
2686 	enum preempt_type preempt_type)
2687 {
2688 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2689 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2690 	char i_buf[PR_REG_ISID_ID_LEN];
2691 
2692 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2693 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
2694 	/*
2695 	 * Do an implicit RELEASE of the existing reservation.
2696 	 */
2697 	if (dev->dev_pr_res_holder)
2698 		__core_scsi3_complete_pro_release(dev, nacl,
2699 				dev->dev_pr_res_holder, 0);
2700 
2701 	dev->dev_pr_res_holder = pr_reg;
2702 	pr_reg->pr_res_holder = 1;
2703 	pr_reg->pr_res_type = type;
2704 	pr_reg->pr_res_scope = scope;
2705 
2706 	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2707 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2708 		tfo->get_fabric_name(), (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2709 		core_scsi3_pr_dump_type(type),
2710 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2711 	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2712 		tfo->get_fabric_name(), (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2713 		nacl->initiatorname, i_buf);
2714 	/*
2715 	 * For PREEMPT_AND_ABORT, add the preempting reservation's
2716 	 * struct t10_pr_registration to the list that will be compared
2717 	 * against received CDBs..
2718 	 */
2719 	if (preempt_and_abort_list)
2720 		list_add_tail(&pr_reg->pr_reg_abort_list,
2721 				preempt_and_abort_list);
2722 }
2723 
2724 static void core_scsi3_release_preempt_and_abort(
2725 	struct list_head *preempt_and_abort_list,
2726 	struct t10_pr_registration *pr_reg_holder)
2727 {
2728 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2729 
2730 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2731 				pr_reg_abort_list) {
2732 
2733 		list_del(&pr_reg->pr_reg_abort_list);
2734 		if (pr_reg_holder == pr_reg)
2735 			continue;
2736 		if (pr_reg->pr_res_holder) {
2737 			pr_warn("pr_reg->pr_res_holder still set\n");
2738 			continue;
2739 		}
2740 
2741 		pr_reg->pr_reg_deve = NULL;
2742 		pr_reg->pr_reg_nacl = NULL;
2743 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
2744 	}
2745 }
2746 
2747 static sense_reason_t
2748 core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
2749 		u64 sa_res_key, enum preempt_type preempt_type)
2750 {
2751 	struct se_device *dev = cmd->se_dev;
2752 	struct se_node_acl *pr_reg_nacl;
2753 	struct se_session *se_sess = cmd->se_sess;
2754 	LIST_HEAD(preempt_and_abort_list);
2755 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2756 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2757 	u32 pr_res_mapped_lun = 0;
2758 	int all_reg = 0, calling_it_nexus = 0, released_regs = 0;
2759 	int prh_type = 0, prh_scope = 0;
2760 
2761 	if (!se_sess)
2762 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2763 
2764 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2765 				se_sess);
2766 	if (!pr_reg_n) {
2767 		pr_err("SPC-3 PR: Unable to locate"
2768 			" PR_REGISTERED *pr_reg for PREEMPT%s\n",
2769 			(preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "");
2770 		return TCM_RESERVATION_CONFLICT;
2771 	}
2772 	if (pr_reg_n->pr_res_key != res_key) {
2773 		core_scsi3_put_pr_reg(pr_reg_n);
2774 		return TCM_RESERVATION_CONFLICT;
2775 	}
2776 	if (scope != PR_SCOPE_LU_SCOPE) {
2777 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2778 		core_scsi3_put_pr_reg(pr_reg_n);
2779 		return TCM_INVALID_PARAMETER_LIST;
2780 	}
2781 
2782 	spin_lock(&dev->dev_reservation_lock);
2783 	pr_res_holder = dev->dev_pr_res_holder;
2784 	if (pr_res_holder &&
2785 	   ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2786 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
2787 		all_reg = 1;
2788 
2789 	if (!all_reg && !sa_res_key) {
2790 		spin_unlock(&dev->dev_reservation_lock);
2791 		core_scsi3_put_pr_reg(pr_reg_n);
2792 		return TCM_INVALID_PARAMETER_LIST;
2793 	}
2794 	/*
2795 	 * From spc4r17, section 5.7.11.4.4 Removing Registrations:
2796 	 *
2797 	 * If the SERVICE ACTION RESERVATION KEY field does not identify a
2798 	 * persistent reservation holder or there is no persistent reservation
2799 	 * holder (i.e., there is no persistent reservation), then the device
2800 	 * server shall perform a preempt by doing the following in an
2801 	 * uninterrupted series of actions. (See below..)
2802 	 */
2803 	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
2804 		/*
2805 		 * No existing or SA Reservation Key matching reservations..
2806 		 *
2807 		 * PROUT SA PREEMPT with All Registrant type reservations are
2808 		 * allowed to be processed without a matching SA Reservation Key
2809 		 */
2810 		spin_lock(&pr_tmpl->registration_lock);
2811 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2812 				&pr_tmpl->registration_list, pr_reg_list) {
2813 			/*
2814 			 * Removing of registrations in non all registrants
2815 			 * type reservations without a matching SA reservation
2816 			 * key.
2817 			 *
2818 			 * a) Remove the registrations for all I_T nexuses
2819 			 *    specified by the SERVICE ACTION RESERVATION KEY
2820 			 *    field;
2821 			 * b) Ignore the contents of the SCOPE and TYPE fields;
2822 			 * c) Process tasks as defined in 5.7.1; and
2823 			 * d) Establish a unit attention condition for the
2824 			 *    initiator port associated with every I_T nexus
2825 			 *    that lost its registration other than the I_T
2826 			 *    nexus on which the PERSISTENT RESERVE OUT command
2827 			 *    was received, with the additional sense code set
2828 			 *    to REGISTRATIONS PREEMPTED.
2829 			 */
2830 			if (!all_reg) {
2831 				if (pr_reg->pr_res_key != sa_res_key)
2832 					continue;
2833 
2834 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2835 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2836 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2837 				__core_scsi3_free_registration(dev, pr_reg,
2838 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2839 						NULL, calling_it_nexus);
2840 				released_regs++;
2841 			} else {
2842 				/*
2843 				 * Case for any existing all registrants type
2844 				 * reservation, follow logic in spc4r17 section
2845 				 * 5.7.11.4 Preempting, Table 52 and Figure 7.
2846 				 *
2847 				 * For a ZERO SA Reservation key, release
2848 				 * all other registrations and do an implicit
2849 				 * release of active persistent reservation.
2850 				 *
2851 				 * For a non-ZERO SA Reservation key, only
2852 				 * release the matching reservation key from
2853 				 * registrations.
2854 				 */
2855 				if ((sa_res_key) &&
2856 				     (pr_reg->pr_res_key != sa_res_key))
2857 					continue;
2858 
2859 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2860 				if (calling_it_nexus)
2861 					continue;
2862 
2863 				pr_reg_nacl = pr_reg->pr_reg_nacl;
2864 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2865 				__core_scsi3_free_registration(dev, pr_reg,
2866 					(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2867 						NULL, 0);
2868 				released_regs++;
2869 			}
2870 			if (!calling_it_nexus)
2871 				core_scsi3_ua_allocate(pr_reg_nacl,
2872 					pr_res_mapped_lun, 0x2A,
2873 					ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2874 		}
2875 		spin_unlock(&pr_tmpl->registration_lock);
2876 		/*
2877 		 * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
2878 		 * a PREEMPT AND ABORT service action sets the SERVICE ACTION
2879 		 * RESERVATION KEY field to a value that does not match any
2880 		 * registered reservation key, then the device server shall
2881 		 * complete the command with RESERVATION CONFLICT status.
2882 		 */
2883 		if (!released_regs) {
2884 			spin_unlock(&dev->dev_reservation_lock);
2885 			core_scsi3_put_pr_reg(pr_reg_n);
2886 			return TCM_RESERVATION_CONFLICT;
2887 		}
2888 		/*
2889 		 * For an existing all registrants type reservation
2890 		 * with a zero SA rservation key, preempt the existing
2891 		 * reservation with the new PR type and scope.
2892 		 */
2893 		if (pr_res_holder && all_reg && !(sa_res_key)) {
2894 			__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
2895 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2896 				type, scope, preempt_type);
2897 
2898 			if (preempt_type == PREEMPT_AND_ABORT)
2899 				core_scsi3_release_preempt_and_abort(
2900 					&preempt_and_abort_list, pr_reg_n);
2901 		}
2902 		spin_unlock(&dev->dev_reservation_lock);
2903 
2904 		if (pr_tmpl->pr_aptpl_active)
2905 			core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
2906 
2907 		core_scsi3_put_pr_reg(pr_reg_n);
2908 		core_scsi3_pr_generation(cmd->se_dev);
2909 		return 0;
2910 	}
2911 	/*
2912 	 * The PREEMPTing SA reservation key matches that of the
2913 	 * existing persistent reservation, first, we check if
2914 	 * we are preempting our own reservation.
2915 	 * From spc4r17, section 5.7.11.4.3 Preempting
2916 	 * persistent reservations and registration handling
2917 	 *
2918 	 * If an all registrants persistent reservation is not
2919 	 * present, it is not an error for the persistent
2920 	 * reservation holder to preempt itself (i.e., a
2921 	 * PERSISTENT RESERVE OUT with a PREEMPT service action
2922 	 * or a PREEMPT AND ABORT service action with the
2923 	 * SERVICE ACTION RESERVATION KEY value equal to the
2924 	 * persistent reservation holder's reservation key that
2925 	 * is received from the persistent reservation holder).
2926 	 * In that case, the device server shall establish the
2927 	 * new persistent reservation and maintain the
2928 	 * registration.
2929 	 */
2930 	prh_type = pr_res_holder->pr_res_type;
2931 	prh_scope = pr_res_holder->pr_res_scope;
2932 	/*
2933 	 * If the SERVICE ACTION RESERVATION KEY field identifies a
2934 	 * persistent reservation holder (see 5.7.10), the device
2935 	 * server shall perform a preempt by doing the following as
2936 	 * an uninterrupted series of actions:
2937 	 *
2938 	 * a) Release the persistent reservation for the holder
2939 	 *    identified by the SERVICE ACTION RESERVATION KEY field;
2940 	 */
2941 	if (pr_reg_n != pr_res_holder)
2942 		__core_scsi3_complete_pro_release(dev,
2943 				pr_res_holder->pr_reg_nacl,
2944 				dev->dev_pr_res_holder, 0);
2945 	/*
2946 	 * b) Remove the registrations for all I_T nexuses identified
2947 	 *    by the SERVICE ACTION RESERVATION KEY field, except the
2948 	 *    I_T nexus that is being used for the PERSISTENT RESERVE
2949 	 *    OUT command. If an all registrants persistent reservation
2950 	 *    is present and the SERVICE ACTION RESERVATION KEY field
2951 	 *    is set to zero, then all registrations shall be removed
2952 	 *    except for that of the I_T nexus that is being used for
2953 	 *    the PERSISTENT RESERVE OUT command;
2954 	 */
2955 	spin_lock(&pr_tmpl->registration_lock);
2956 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2957 			&pr_tmpl->registration_list, pr_reg_list) {
2958 
2959 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2960 		if (calling_it_nexus)
2961 			continue;
2962 
2963 		if (pr_reg->pr_res_key != sa_res_key)
2964 			continue;
2965 
2966 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2967 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2968 		__core_scsi3_free_registration(dev, pr_reg,
2969 				(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2970 				calling_it_nexus);
2971 		/*
2972 		 * e) Establish a unit attention condition for the initiator
2973 		 *    port associated with every I_T nexus that lost its
2974 		 *    persistent reservation and/or registration, with the
2975 		 *    additional sense code set to REGISTRATIONS PREEMPTED;
2976 		 */
2977 		core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
2978 				ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2979 	}
2980 	spin_unlock(&pr_tmpl->registration_lock);
2981 	/*
2982 	 * c) Establish a persistent reservation for the preempting
2983 	 *    I_T nexus using the contents of the SCOPE and TYPE fields;
2984 	 */
2985 	__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
2986 			(preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2987 			type, scope, preempt_type);
2988 	/*
2989 	 * d) Process tasks as defined in 5.7.1;
2990 	 * e) See above..
2991 	 * f) If the type or scope has changed, then for every I_T nexus
2992 	 *    whose reservation key was not removed, except for the I_T
2993 	 *    nexus on which the PERSISTENT RESERVE OUT command was
2994 	 *    received, the device server shall establish a unit
2995 	 *    attention condition for the initiator port associated with
2996 	 *    that I_T nexus, with the additional sense code set to
2997 	 *    RESERVATIONS RELEASED. If the type or scope have not
2998 	 *    changed, then no unit attention condition(s) shall be
2999 	 *    established for this reason.
3000 	 */
3001 	if ((prh_type != type) || (prh_scope != scope)) {
3002 		spin_lock(&pr_tmpl->registration_lock);
3003 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3004 				&pr_tmpl->registration_list, pr_reg_list) {
3005 
3006 			calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3007 			if (calling_it_nexus)
3008 				continue;
3009 
3010 			core_scsi3_ua_allocate(pr_reg->pr_reg_nacl,
3011 					pr_reg->pr_res_mapped_lun, 0x2A,
3012 					ASCQ_2AH_RESERVATIONS_RELEASED);
3013 		}
3014 		spin_unlock(&pr_tmpl->registration_lock);
3015 	}
3016 	spin_unlock(&dev->dev_reservation_lock);
3017 	/*
3018 	 * Call LUN_RESET logic upon list of struct t10_pr_registration,
3019 	 * All received CDBs for the matching existing reservation and
3020 	 * registrations undergo ABORT_TASK logic.
3021 	 *
3022 	 * From there, core_scsi3_release_preempt_and_abort() will
3023 	 * release every registration in the list (which have already
3024 	 * been removed from the primary pr_reg list), except the
3025 	 * new persistent reservation holder, the calling Initiator Port.
3026 	 */
3027 	if (preempt_type == PREEMPT_AND_ABORT) {
3028 		core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3029 		core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3030 						pr_reg_n);
3031 	}
3032 
3033 	if (pr_tmpl->pr_aptpl_active)
3034 		core_scsi3_update_and_write_aptpl(cmd->se_dev, true);
3035 
3036 	core_scsi3_put_pr_reg(pr_reg_n);
3037 	core_scsi3_pr_generation(cmd->se_dev);
3038 	return 0;
3039 }
3040 
3041 static sense_reason_t
3042 core_scsi3_emulate_pro_preempt(struct se_cmd *cmd, int type, int scope,
3043 		u64 res_key, u64 sa_res_key, enum preempt_type preempt_type)
3044 {
3045 	switch (type) {
3046 	case PR_TYPE_WRITE_EXCLUSIVE:
3047 	case PR_TYPE_EXCLUSIVE_ACCESS:
3048 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3049 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3050 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3051 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3052 		return core_scsi3_pro_preempt(cmd, type, scope, res_key,
3053 					      sa_res_key, preempt_type);
3054 	default:
3055 		pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3056 			" Type: 0x%02x\n", (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "", type);
3057 		return TCM_INVALID_CDB_FIELD;
3058 	}
3059 }
3060 
3061 
3062 static sense_reason_t
3063 core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
3064 		u64 sa_res_key, int aptpl, int unreg)
3065 {
3066 	struct se_session *se_sess = cmd->se_sess;
3067 	struct se_device *dev = cmd->se_dev;
3068 	struct se_dev_entry *dest_se_deve = NULL;
3069 	struct se_lun *se_lun = cmd->se_lun;
3070 	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3071 	struct se_port *se_port;
3072 	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3073 	struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3074 	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3075 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3076 	unsigned char *buf;
3077 	unsigned char *initiator_str;
3078 	char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
3079 	u32 tid_len, tmp_tid_len;
3080 	int new_reg = 0, type, scope, matching_iname;
3081 	sense_reason_t ret;
3082 	unsigned short rtpi;
3083 	unsigned char proto_ident;
3084 
3085 	if (!se_sess || !se_lun) {
3086 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3087 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3088 	}
3089 
3090 	memset(dest_iport, 0, 64);
3091 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3092 	se_tpg = se_sess->se_tpg;
3093 	tf_ops = se_tpg->se_tpg_tfo;
3094 	/*
3095 	 * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3096 	 *	Register behaviors for a REGISTER AND MOVE service action
3097 	 *
3098 	 * Locate the existing *pr_reg via struct se_node_acl pointers
3099 	 */
3100 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3101 				se_sess);
3102 	if (!pr_reg) {
3103 		pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3104 			" *pr_reg for REGISTER_AND_MOVE\n");
3105 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3106 	}
3107 	/*
3108 	 * The provided reservation key much match the existing reservation key
3109 	 * provided during this initiator's I_T nexus registration.
3110 	 */
3111 	if (res_key != pr_reg->pr_res_key) {
3112 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3113 			" res_key: 0x%016Lx does not match existing SA REGISTER"
3114 			" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3115 		ret = TCM_RESERVATION_CONFLICT;
3116 		goto out_put_pr_reg;
3117 	}
3118 	/*
3119 	 * The service active reservation key needs to be non zero
3120 	 */
3121 	if (!sa_res_key) {
3122 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3123 			" sa_res_key\n");
3124 		ret = TCM_INVALID_PARAMETER_LIST;
3125 		goto out_put_pr_reg;
3126 	}
3127 
3128 	/*
3129 	 * Determine the Relative Target Port Identifier where the reservation
3130 	 * will be moved to for the TransportID containing SCSI initiator WWN
3131 	 * information.
3132 	 */
3133 	buf = transport_kmap_data_sg(cmd);
3134 	if (!buf) {
3135 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3136 		goto out_put_pr_reg;
3137 	}
3138 
3139 	rtpi = (buf[18] & 0xff) << 8;
3140 	rtpi |= buf[19] & 0xff;
3141 	tid_len = (buf[20] & 0xff) << 24;
3142 	tid_len |= (buf[21] & 0xff) << 16;
3143 	tid_len |= (buf[22] & 0xff) << 8;
3144 	tid_len |= buf[23] & 0xff;
3145 	transport_kunmap_data_sg(cmd);
3146 	buf = NULL;
3147 
3148 	if ((tid_len + 24) != cmd->data_length) {
3149 		pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3150 			" does not equal CDB data_length: %u\n", tid_len,
3151 			cmd->data_length);
3152 		ret = TCM_INVALID_PARAMETER_LIST;
3153 		goto out_put_pr_reg;
3154 	}
3155 
3156 	spin_lock(&dev->se_port_lock);
3157 	list_for_each_entry(se_port, &dev->dev_sep_list, sep_list) {
3158 		if (se_port->sep_rtpi != rtpi)
3159 			continue;
3160 		dest_se_tpg = se_port->sep_tpg;
3161 		if (!dest_se_tpg)
3162 			continue;
3163 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3164 		if (!dest_tf_ops)
3165 			continue;
3166 
3167 		atomic_inc(&dest_se_tpg->tpg_pr_ref_count);
3168 		smp_mb__after_atomic_inc();
3169 		spin_unlock(&dev->se_port_lock);
3170 
3171 		if (core_scsi3_tpg_depend_item(dest_se_tpg)) {
3172 			pr_err("core_scsi3_tpg_depend_item() failed"
3173 				" for dest_se_tpg\n");
3174 			atomic_dec(&dest_se_tpg->tpg_pr_ref_count);
3175 			smp_mb__after_atomic_dec();
3176 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3177 			goto out_put_pr_reg;
3178 		}
3179 
3180 		spin_lock(&dev->se_port_lock);
3181 		break;
3182 	}
3183 	spin_unlock(&dev->se_port_lock);
3184 
3185 	if (!dest_se_tpg || !dest_tf_ops) {
3186 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3187 			" fabric ops from Relative Target Port Identifier:"
3188 			" %hu\n", rtpi);
3189 		ret = TCM_INVALID_PARAMETER_LIST;
3190 		goto out_put_pr_reg;
3191 	}
3192 
3193 	buf = transport_kmap_data_sg(cmd);
3194 	if (!buf) {
3195 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3196 		goto out_put_pr_reg;
3197 	}
3198 	proto_ident = (buf[24] & 0x0f);
3199 
3200 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3201 			" 0x%02x\n", proto_ident);
3202 
3203 	if (proto_ident != dest_tf_ops->get_fabric_proto_ident(dest_se_tpg)) {
3204 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3205 			" proto_ident: 0x%02x does not match ident: 0x%02x"
3206 			" from fabric: %s\n", proto_ident,
3207 			dest_tf_ops->get_fabric_proto_ident(dest_se_tpg),
3208 			dest_tf_ops->get_fabric_name());
3209 		ret = TCM_INVALID_PARAMETER_LIST;
3210 		goto out;
3211 	}
3212 	if (dest_tf_ops->tpg_parse_pr_out_transport_id == NULL) {
3213 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Fabric does not"
3214 			" containg a valid tpg_parse_pr_out_transport_id"
3215 			" function pointer\n");
3216 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3217 		goto out;
3218 	}
3219 	initiator_str = dest_tf_ops->tpg_parse_pr_out_transport_id(dest_se_tpg,
3220 			(const char *)&buf[24], &tmp_tid_len, &iport_ptr);
3221 	if (!initiator_str) {
3222 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3223 			" initiator_str from Transport ID\n");
3224 		ret = TCM_INVALID_PARAMETER_LIST;
3225 		goto out;
3226 	}
3227 
3228 	transport_kunmap_data_sg(cmd);
3229 	buf = NULL;
3230 
3231 	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3232 		" %s\n", dest_tf_ops->get_fabric_name(), (iport_ptr != NULL) ?
3233 		"port" : "device", initiator_str, (iport_ptr != NULL) ?
3234 		iport_ptr : "");
3235 	/*
3236 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3237 	 * action specifies a TransportID that is the same as the initiator port
3238 	 * of the I_T nexus for the command received, then the command shall
3239 	 * be terminated with CHECK CONDITION status, with the sense key set to
3240 	 * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3241 	 * IN PARAMETER LIST.
3242 	 */
3243 	pr_reg_nacl = pr_reg->pr_reg_nacl;
3244 	matching_iname = (!strcmp(initiator_str,
3245 				  pr_reg_nacl->initiatorname)) ? 1 : 0;
3246 	if (!matching_iname)
3247 		goto after_iport_check;
3248 
3249 	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3250 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3251 			" matches: %s on received I_T Nexus\n", initiator_str,
3252 			pr_reg_nacl->initiatorname);
3253 		ret = TCM_INVALID_PARAMETER_LIST;
3254 		goto out;
3255 	}
3256 	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3257 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3258 			" matches: %s %s on received I_T Nexus\n",
3259 			initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3260 			pr_reg->pr_reg_isid);
3261 		ret = TCM_INVALID_PARAMETER_LIST;
3262 		goto out;
3263 	}
3264 after_iport_check:
3265 	/*
3266 	 * Locate the destination struct se_node_acl from the received Transport ID
3267 	 */
3268 	spin_lock_irq(&dest_se_tpg->acl_node_lock);
3269 	dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3270 				initiator_str);
3271 	if (dest_node_acl) {
3272 		atomic_inc(&dest_node_acl->acl_pr_ref_count);
3273 		smp_mb__after_atomic_inc();
3274 	}
3275 	spin_unlock_irq(&dest_se_tpg->acl_node_lock);
3276 
3277 	if (!dest_node_acl) {
3278 		pr_err("Unable to locate %s dest_node_acl for"
3279 			" TransportID%s\n", dest_tf_ops->get_fabric_name(),
3280 			initiator_str);
3281 		ret = TCM_INVALID_PARAMETER_LIST;
3282 		goto out;
3283 	}
3284 
3285 	if (core_scsi3_nodeacl_depend_item(dest_node_acl)) {
3286 		pr_err("core_scsi3_nodeacl_depend_item() for"
3287 			" dest_node_acl\n");
3288 		atomic_dec(&dest_node_acl->acl_pr_ref_count);
3289 		smp_mb__after_atomic_dec();
3290 		dest_node_acl = NULL;
3291 		ret = TCM_INVALID_PARAMETER_LIST;
3292 		goto out;
3293 	}
3294 
3295 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3296 		" %s from TransportID\n", dest_tf_ops->get_fabric_name(),
3297 		dest_node_acl->initiatorname);
3298 
3299 	/*
3300 	 * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3301 	 * PORT IDENTIFIER.
3302 	 */
3303 	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3304 	if (!dest_se_deve) {
3305 		pr_err("Unable to locate %s dest_se_deve from RTPI:"
3306 			" %hu\n",  dest_tf_ops->get_fabric_name(), rtpi);
3307 		ret = TCM_INVALID_PARAMETER_LIST;
3308 		goto out;
3309 	}
3310 
3311 	if (core_scsi3_lunacl_depend_item(dest_se_deve)) {
3312 		pr_err("core_scsi3_lunacl_depend_item() failed\n");
3313 		atomic_dec(&dest_se_deve->pr_ref_count);
3314 		smp_mb__after_atomic_dec();
3315 		dest_se_deve = NULL;
3316 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3317 		goto out;
3318 	}
3319 
3320 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3321 		" ACL for dest_se_deve->mapped_lun: %u\n",
3322 		dest_tf_ops->get_fabric_name(), dest_node_acl->initiatorname,
3323 		dest_se_deve->mapped_lun);
3324 
3325 	/*
3326 	 * A persistent reservation needs to already existing in order to
3327 	 * successfully complete the REGISTER_AND_MOVE service action..
3328 	 */
3329 	spin_lock(&dev->dev_reservation_lock);
3330 	pr_res_holder = dev->dev_pr_res_holder;
3331 	if (!pr_res_holder) {
3332 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3333 			" currently held\n");
3334 		spin_unlock(&dev->dev_reservation_lock);
3335 		ret = TCM_INVALID_CDB_FIELD;
3336 		goto out;
3337 	}
3338 	/*
3339 	 * The received on I_T Nexus must be the reservation holder.
3340 	 *
3341 	 * From spc4r17 section 5.7.8  Table 50 --
3342 	 * 	Register behaviors for a REGISTER AND MOVE service action
3343 	 */
3344 	if (pr_res_holder != pr_reg) {
3345 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3346 			" Nexus is not reservation holder\n");
3347 		spin_unlock(&dev->dev_reservation_lock);
3348 		ret = TCM_RESERVATION_CONFLICT;
3349 		goto out;
3350 	}
3351 	/*
3352 	 * From spc4r17 section 5.7.8: registering and moving reservation
3353 	 *
3354 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3355 	 * action is received and the established persistent reservation is a
3356 	 * Write Exclusive - All Registrants type or Exclusive Access -
3357 	 * All Registrants type reservation, then the command shall be completed
3358 	 * with RESERVATION CONFLICT status.
3359 	 */
3360 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3361 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3362 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3363 			" reservation for type: %s\n",
3364 			core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3365 		spin_unlock(&dev->dev_reservation_lock);
3366 		ret = TCM_RESERVATION_CONFLICT;
3367 		goto out;
3368 	}
3369 	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3370 	/*
3371 	 * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3372 	 */
3373 	type = pr_res_holder->pr_res_type;
3374 	scope = pr_res_holder->pr_res_type;
3375 	/*
3376 	 * c) Associate the reservation key specified in the SERVICE ACTION
3377 	 *    RESERVATION KEY field with the I_T nexus specified as the
3378 	 *    destination of the register and move, where:
3379 	 *    A) The I_T nexus is specified by the TransportID and the
3380 	 *	 RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3381 	 *    B) Regardless of the TransportID format used, the association for
3382 	 *       the initiator port is based on either the initiator port name
3383 	 *       (see 3.1.71) on SCSI transport protocols where port names are
3384 	 *       required or the initiator port identifier (see 3.1.70) on SCSI
3385 	 *       transport protocols where port names are not required;
3386 	 * d) Register the reservation key specified in the SERVICE ACTION
3387 	 *    RESERVATION KEY field;
3388 	 * e) Retain the reservation key specified in the SERVICE ACTION
3389 	 *    RESERVATION KEY field and associated information;
3390 	 *
3391 	 * Also, It is not an error for a REGISTER AND MOVE service action to
3392 	 * register an I_T nexus that is already registered with the same
3393 	 * reservation key or a different reservation key.
3394 	 */
3395 	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3396 					iport_ptr);
3397 	if (!dest_pr_reg) {
3398 		if (core_scsi3_alloc_registration(cmd->se_dev,
3399 				dest_node_acl, dest_se_deve, iport_ptr,
3400 				sa_res_key, 0, aptpl, 2, 1)) {
3401 			spin_unlock(&dev->dev_reservation_lock);
3402 			ret = TCM_INVALID_PARAMETER_LIST;
3403 			goto out;
3404 		}
3405 		dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3406 						iport_ptr);
3407 		new_reg = 1;
3408 	}
3409 	/*
3410 	 * f) Release the persistent reservation for the persistent reservation
3411 	 *    holder (i.e., the I_T nexus on which the
3412 	 */
3413 	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
3414 			dev->dev_pr_res_holder, 0);
3415 	/*
3416 	 * g) Move the persistent reservation to the specified I_T nexus using
3417 	 *    the same scope and type as the persistent reservation released in
3418 	 *    item f); and
3419 	 */
3420 	dev->dev_pr_res_holder = dest_pr_reg;
3421 	dest_pr_reg->pr_res_holder = 1;
3422 	dest_pr_reg->pr_res_type = type;
3423 	pr_reg->pr_res_scope = scope;
3424 	core_pr_dump_initiator_port(pr_reg, i_buf, PR_REG_ISID_ID_LEN);
3425 	/*
3426 	 * Increment PRGeneration for existing registrations..
3427 	 */
3428 	if (!new_reg)
3429 		dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3430 	spin_unlock(&dev->dev_reservation_lock);
3431 
3432 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3433 		" created new reservation holder TYPE: %s on object RTPI:"
3434 		" %hu  PRGeneration: 0x%08x\n", dest_tf_ops->get_fabric_name(),
3435 		core_scsi3_pr_dump_type(type), rtpi,
3436 		dest_pr_reg->pr_res_generation);
3437 	pr_debug("SPC-3 PR Successfully moved reservation from"
3438 		" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3439 		tf_ops->get_fabric_name(), pr_reg_nacl->initiatorname,
3440 		i_buf, dest_tf_ops->get_fabric_name(),
3441 		dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3442 		iport_ptr : "");
3443 	/*
3444 	 * It is now safe to release configfs group dependencies for destination
3445 	 * of Transport ID Initiator Device/Port Identifier
3446 	 */
3447 	core_scsi3_lunacl_undepend_item(dest_se_deve);
3448 	core_scsi3_nodeacl_undepend_item(dest_node_acl);
3449 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3450 	/*
3451 	 * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3452 	 * nexus on which PERSISTENT RESERVE OUT command was received.
3453 	 */
3454 	if (unreg) {
3455 		spin_lock(&pr_tmpl->registration_lock);
3456 		__core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3457 		spin_unlock(&pr_tmpl->registration_lock);
3458 	} else
3459 		core_scsi3_put_pr_reg(pr_reg);
3460 
3461 	core_scsi3_update_and_write_aptpl(cmd->se_dev, aptpl);
3462 
3463 	transport_kunmap_data_sg(cmd);
3464 
3465 	core_scsi3_put_pr_reg(dest_pr_reg);
3466 	return 0;
3467 out:
3468 	if (buf)
3469 		transport_kunmap_data_sg(cmd);
3470 	if (dest_se_deve)
3471 		core_scsi3_lunacl_undepend_item(dest_se_deve);
3472 	if (dest_node_acl)
3473 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
3474 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3475 
3476 out_put_pr_reg:
3477 	core_scsi3_put_pr_reg(pr_reg);
3478 	return ret;
3479 }
3480 
3481 static unsigned long long core_scsi3_extract_reservation_key(unsigned char *cdb)
3482 {
3483 	unsigned int __v1, __v2;
3484 
3485 	__v1 = (cdb[0] << 24) | (cdb[1] << 16) | (cdb[2] << 8) | cdb[3];
3486 	__v2 = (cdb[4] << 24) | (cdb[5] << 16) | (cdb[6] << 8) | cdb[7];
3487 
3488 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
3489 }
3490 
3491 /*
3492  * See spc4r17 section 6.14 Table 170
3493  */
3494 sense_reason_t
3495 target_scsi3_emulate_pr_out(struct se_cmd *cmd)
3496 {
3497 	unsigned char *cdb = &cmd->t_task_cdb[0];
3498 	unsigned char *buf;
3499 	u64 res_key, sa_res_key;
3500 	int sa, scope, type, aptpl;
3501 	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3502 	sense_reason_t ret;
3503 
3504 	/*
3505 	 * Following spc2r20 5.5.1 Reservations overview:
3506 	 *
3507 	 * If a logical unit has been reserved by any RESERVE command and is
3508 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3509 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
3510 	 * initiator or service action and shall terminate with a RESERVATION
3511 	 * CONFLICT status.
3512 	 */
3513 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
3514 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3515 			" SPC-2 reservation is held, returning"
3516 			" RESERVATION_CONFLICT\n");
3517 		return TCM_RESERVATION_CONFLICT;
3518 	}
3519 
3520 	/*
3521 	 * FIXME: A NULL struct se_session pointer means an this is not coming from
3522 	 * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3523 	 */
3524 	if (!cmd->se_sess)
3525 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3526 
3527 	if (cmd->data_length < 24) {
3528 		pr_warn("SPC-PR: Received PR OUT parameter list"
3529 			" length too small: %u\n", cmd->data_length);
3530 		return TCM_INVALID_PARAMETER_LIST;
3531 	}
3532 
3533 	/*
3534 	 * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3535 	 */
3536 	sa = (cdb[1] & 0x1f);
3537 	scope = (cdb[2] & 0xf0);
3538 	type = (cdb[2] & 0x0f);
3539 
3540 	buf = transport_kmap_data_sg(cmd);
3541 	if (!buf)
3542 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3543 
3544 	/*
3545 	 * From PERSISTENT_RESERVE_OUT parameter list (payload)
3546 	 */
3547 	res_key = core_scsi3_extract_reservation_key(&buf[0]);
3548 	sa_res_key = core_scsi3_extract_reservation_key(&buf[8]);
3549 	/*
3550 	 * REGISTER_AND_MOVE uses a different SA parameter list containing
3551 	 * SCSI TransportIDs.
3552 	 */
3553 	if (sa != PRO_REGISTER_AND_MOVE) {
3554 		spec_i_pt = (buf[20] & 0x08);
3555 		all_tg_pt = (buf[20] & 0x04);
3556 		aptpl = (buf[20] & 0x01);
3557 	} else {
3558 		aptpl = (buf[17] & 0x01);
3559 		unreg = (buf[17] & 0x02);
3560 	}
3561 	transport_kunmap_data_sg(cmd);
3562 	buf = NULL;
3563 
3564 	/*
3565 	 * SPEC_I_PT=1 is only valid for Service action: REGISTER
3566 	 */
3567 	if (spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER))
3568 		return TCM_INVALID_PARAMETER_LIST;
3569 
3570 	/*
3571 	 * From spc4r17 section 6.14:
3572 	 *
3573 	 * If the SPEC_I_PT bit is set to zero, the service action is not
3574 	 * REGISTER AND MOVE, and the parameter list length is not 24, then
3575 	 * the command shall be terminated with CHECK CONDITION status, with
3576 	 * the sense key set to ILLEGAL REQUEST, and the additional sense
3577 	 * code set to PARAMETER LIST LENGTH ERROR.
3578 	 */
3579 	if (!spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER_AND_MOVE) &&
3580 	    (cmd->data_length != 24)) {
3581 		pr_warn("SPC-PR: Received PR OUT illegal parameter"
3582 			" list length: %u\n", cmd->data_length);
3583 		return TCM_INVALID_PARAMETER_LIST;
3584 	}
3585 
3586 	/*
3587 	 * (core_scsi3_emulate_pro_* function parameters
3588 	 * are defined by spc4r17 Table 174:
3589 	 * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3590 	 */
3591 	switch (sa) {
3592 	case PRO_REGISTER:
3593 		ret = core_scsi3_emulate_pro_register(cmd,
3594 			res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER);
3595 		break;
3596 	case PRO_RESERVE:
3597 		ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3598 		break;
3599 	case PRO_RELEASE:
3600 		ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3601 		break;
3602 	case PRO_CLEAR:
3603 		ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3604 		break;
3605 	case PRO_PREEMPT:
3606 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3607 					res_key, sa_res_key, PREEMPT);
3608 		break;
3609 	case PRO_PREEMPT_AND_ABORT:
3610 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3611 					res_key, sa_res_key, PREEMPT_AND_ABORT);
3612 		break;
3613 	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3614 		ret = core_scsi3_emulate_pro_register(cmd,
3615 			0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, REGISTER_AND_IGNORE_EXISTING_KEY);
3616 		break;
3617 	case PRO_REGISTER_AND_MOVE:
3618 		ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3619 				sa_res_key, aptpl, unreg);
3620 		break;
3621 	default:
3622 		pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3623 			" action: 0x%02x\n", cdb[1] & 0x1f);
3624 		return TCM_INVALID_CDB_FIELD;
3625 	}
3626 
3627 	if (!ret)
3628 		target_complete_cmd(cmd, GOOD);
3629 	return ret;
3630 }
3631 
3632 /*
3633  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3634  *
3635  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3636  */
3637 static sense_reason_t
3638 core_scsi3_pri_read_keys(struct se_cmd *cmd)
3639 {
3640 	struct se_device *dev = cmd->se_dev;
3641 	struct t10_pr_registration *pr_reg;
3642 	unsigned char *buf;
3643 	u32 add_len = 0, off = 8;
3644 
3645 	if (cmd->data_length < 8) {
3646 		pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3647 			" too small\n", cmd->data_length);
3648 		return TCM_INVALID_CDB_FIELD;
3649 	}
3650 
3651 	buf = transport_kmap_data_sg(cmd);
3652 	if (!buf)
3653 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3654 
3655 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3656 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3657 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3658 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3659 
3660 	spin_lock(&dev->t10_pr.registration_lock);
3661 	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
3662 			pr_reg_list) {
3663 		/*
3664 		 * Check for overflow of 8byte PRI READ_KEYS payload and
3665 		 * next reservation key list descriptor.
3666 		 */
3667 		if ((add_len + 8) > (cmd->data_length - 8))
3668 			break;
3669 
3670 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3671 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3672 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3673 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3674 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3675 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3676 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3677 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3678 
3679 		add_len += 8;
3680 	}
3681 	spin_unlock(&dev->t10_pr.registration_lock);
3682 
3683 	buf[4] = ((add_len >> 24) & 0xff);
3684 	buf[5] = ((add_len >> 16) & 0xff);
3685 	buf[6] = ((add_len >> 8) & 0xff);
3686 	buf[7] = (add_len & 0xff);
3687 
3688 	transport_kunmap_data_sg(cmd);
3689 
3690 	return 0;
3691 }
3692 
3693 /*
3694  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3695  *
3696  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3697  */
3698 static sense_reason_t
3699 core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3700 {
3701 	struct se_device *dev = cmd->se_dev;
3702 	struct t10_pr_registration *pr_reg;
3703 	unsigned char *buf;
3704 	u64 pr_res_key;
3705 	u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
3706 
3707 	if (cmd->data_length < 8) {
3708 		pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3709 			" too small\n", cmd->data_length);
3710 		return TCM_INVALID_CDB_FIELD;
3711 	}
3712 
3713 	buf = transport_kmap_data_sg(cmd);
3714 	if (!buf)
3715 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3716 
3717 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3718 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3719 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3720 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3721 
3722 	spin_lock(&dev->dev_reservation_lock);
3723 	pr_reg = dev->dev_pr_res_holder;
3724 	if (pr_reg) {
3725 		/*
3726 		 * Set the hardcoded Additional Length
3727 		 */
3728 		buf[4] = ((add_len >> 24) & 0xff);
3729 		buf[5] = ((add_len >> 16) & 0xff);
3730 		buf[6] = ((add_len >> 8) & 0xff);
3731 		buf[7] = (add_len & 0xff);
3732 
3733 		if (cmd->data_length < 22)
3734 			goto err;
3735 
3736 		/*
3737 		 * Set the Reservation key.
3738 		 *
3739 		 * From spc4r17, section 5.7.10:
3740 		 * A persistent reservation holder has its reservation key
3741 		 * returned in the parameter data from a PERSISTENT
3742 		 * RESERVE IN command with READ RESERVATION service action as
3743 		 * follows:
3744 		 * a) For a persistent reservation of the type Write Exclusive
3745 		 *    - All Registrants or Exclusive Access ­ All Regitrants,
3746 		 *      the reservation key shall be set to zero; or
3747 		 * b) For all other persistent reservation types, the
3748 		 *    reservation key shall be set to the registered
3749 		 *    reservation key for the I_T nexus that holds the
3750 		 *    persistent reservation.
3751 		 */
3752 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3753 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3754 			pr_res_key = 0;
3755 		else
3756 			pr_res_key = pr_reg->pr_res_key;
3757 
3758 		buf[8] = ((pr_res_key >> 56) & 0xff);
3759 		buf[9] = ((pr_res_key >> 48) & 0xff);
3760 		buf[10] = ((pr_res_key >> 40) & 0xff);
3761 		buf[11] = ((pr_res_key >> 32) & 0xff);
3762 		buf[12] = ((pr_res_key >> 24) & 0xff);
3763 		buf[13] = ((pr_res_key >> 16) & 0xff);
3764 		buf[14] = ((pr_res_key >> 8) & 0xff);
3765 		buf[15] = (pr_res_key & 0xff);
3766 		/*
3767 		 * Set the SCOPE and TYPE
3768 		 */
3769 		buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3770 			  (pr_reg->pr_res_type & 0x0f);
3771 	}
3772 
3773 err:
3774 	spin_unlock(&dev->dev_reservation_lock);
3775 	transport_kunmap_data_sg(cmd);
3776 
3777 	return 0;
3778 }
3779 
3780 /*
3781  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3782  *
3783  * See spc4r17 section 6.13.4 Table 165
3784  */
3785 static sense_reason_t
3786 core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3787 {
3788 	struct se_device *dev = cmd->se_dev;
3789 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3790 	unsigned char *buf;
3791 	u16 add_len = 8; /* Hardcoded to 8. */
3792 
3793 	if (cmd->data_length < 6) {
3794 		pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
3795 			" %u too small\n", cmd->data_length);
3796 		return TCM_INVALID_CDB_FIELD;
3797 	}
3798 
3799 	buf = transport_kmap_data_sg(cmd);
3800 	if (!buf)
3801 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3802 
3803 	buf[0] = ((add_len << 8) & 0xff);
3804 	buf[1] = (add_len & 0xff);
3805 	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
3806 	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
3807 	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
3808 	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
3809 	/*
3810 	 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
3811 	 * set the TMV: Task Mask Valid bit.
3812 	 */
3813 	buf[3] |= 0x80;
3814 	/*
3815 	 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
3816 	 */
3817 	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
3818 	/*
3819 	 * PTPL_A: Persistence across Target Power Loss Active bit
3820 	 */
3821 	if (pr_tmpl->pr_aptpl_active)
3822 		buf[3] |= 0x01;
3823 	/*
3824 	 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
3825 	 */
3826 	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3827 	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
3828 	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
3829 	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
3830 	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
3831 	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3832 
3833 	transport_kunmap_data_sg(cmd);
3834 
3835 	return 0;
3836 }
3837 
3838 /*
3839  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
3840  *
3841  * See spc4r17 section 6.13.5 Table 168 and 169
3842  */
3843 static sense_reason_t
3844 core_scsi3_pri_read_full_status(struct se_cmd *cmd)
3845 {
3846 	struct se_device *dev = cmd->se_dev;
3847 	struct se_node_acl *se_nacl;
3848 	struct se_portal_group *se_tpg;
3849 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
3850 	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3851 	unsigned char *buf;
3852 	u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
3853 	u32 off = 8; /* off into first Full Status descriptor */
3854 	int format_code = 0;
3855 
3856 	if (cmd->data_length < 8) {
3857 		pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
3858 			" too small\n", cmd->data_length);
3859 		return TCM_INVALID_CDB_FIELD;
3860 	}
3861 
3862 	buf = transport_kmap_data_sg(cmd);
3863 	if (!buf)
3864 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3865 
3866 	buf[0] = ((dev->t10_pr.pr_generation >> 24) & 0xff);
3867 	buf[1] = ((dev->t10_pr.pr_generation >> 16) & 0xff);
3868 	buf[2] = ((dev->t10_pr.pr_generation >> 8) & 0xff);
3869 	buf[3] = (dev->t10_pr.pr_generation & 0xff);
3870 
3871 	spin_lock(&pr_tmpl->registration_lock);
3872 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3873 			&pr_tmpl->registration_list, pr_reg_list) {
3874 
3875 		se_nacl = pr_reg->pr_reg_nacl;
3876 		se_tpg = pr_reg->pr_reg_nacl->se_tpg;
3877 		add_desc_len = 0;
3878 
3879 		atomic_inc(&pr_reg->pr_res_holders);
3880 		smp_mb__after_atomic_inc();
3881 		spin_unlock(&pr_tmpl->registration_lock);
3882 		/*
3883 		 * Determine expected length of $FABRIC_MOD specific
3884 		 * TransportID full status descriptor..
3885 		 */
3886 		exp_desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id_len(
3887 				se_tpg, se_nacl, pr_reg, &format_code);
3888 
3889 		if ((exp_desc_len + add_len) > cmd->data_length) {
3890 			pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
3891 				" out of buffer: %d\n", cmd->data_length);
3892 			spin_lock(&pr_tmpl->registration_lock);
3893 			atomic_dec(&pr_reg->pr_res_holders);
3894 			smp_mb__after_atomic_dec();
3895 			break;
3896 		}
3897 		/*
3898 		 * Set RESERVATION KEY
3899 		 */
3900 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3901 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3902 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3903 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3904 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3905 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3906 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3907 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3908 		off += 4; /* Skip Over Reserved area */
3909 
3910 		/*
3911 		 * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
3912 		 */
3913 		if (pr_reg->pr_reg_all_tg_pt)
3914 			buf[off] = 0x02;
3915 		/*
3916 		 * The struct se_lun pointer will be present for the
3917 		 * reservation holder for PR_HOLDER bit.
3918 		 *
3919 		 * Also, if this registration is the reservation
3920 		 * holder, fill in SCOPE and TYPE in the next byte.
3921 		 */
3922 		if (pr_reg->pr_res_holder) {
3923 			buf[off++] |= 0x01;
3924 			buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
3925 				     (pr_reg->pr_res_type & 0x0f);
3926 		} else
3927 			off += 2;
3928 
3929 		off += 4; /* Skip over reserved area */
3930 		/*
3931 		 * From spc4r17 6.3.15:
3932 		 *
3933 		 * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
3934 		 * IDENTIFIER field contains the relative port identifier (see
3935 		 * 3.1.120) of the target port that is part of the I_T nexus
3936 		 * described by this full status descriptor. If the ALL_TG_PT
3937 		 * bit is set to one, the contents of the RELATIVE TARGET PORT
3938 		 * IDENTIFIER field are not defined by this standard.
3939 		 */
3940 		if (!pr_reg->pr_reg_all_tg_pt) {
3941 			struct se_port *port = pr_reg->pr_reg_tg_pt_lun->lun_sep;
3942 
3943 			buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
3944 			buf[off++] = (port->sep_rtpi & 0xff);
3945 		} else
3946 			off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */
3947 
3948 		/*
3949 		 * Now, have the $FABRIC_MOD fill in the protocol identifier
3950 		 */
3951 		desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id(se_tpg,
3952 				se_nacl, pr_reg, &format_code, &buf[off+4]);
3953 
3954 		spin_lock(&pr_tmpl->registration_lock);
3955 		atomic_dec(&pr_reg->pr_res_holders);
3956 		smp_mb__after_atomic_dec();
3957 		/*
3958 		 * Set the ADDITIONAL DESCRIPTOR LENGTH
3959 		 */
3960 		buf[off++] = ((desc_len >> 24) & 0xff);
3961 		buf[off++] = ((desc_len >> 16) & 0xff);
3962 		buf[off++] = ((desc_len >> 8) & 0xff);
3963 		buf[off++] = (desc_len & 0xff);
3964 		/*
3965 		 * Size of full desctipor header minus TransportID
3966 		 * containing $FABRIC_MOD specific) initiator device/port
3967 		 * WWN information.
3968 		 *
3969 		 *  See spc4r17 Section 6.13.5 Table 169
3970 		 */
3971 		add_desc_len = (24 + desc_len);
3972 
3973 		off += desc_len;
3974 		add_len += add_desc_len;
3975 	}
3976 	spin_unlock(&pr_tmpl->registration_lock);
3977 	/*
3978 	 * Set ADDITIONAL_LENGTH
3979 	 */
3980 	buf[4] = ((add_len >> 24) & 0xff);
3981 	buf[5] = ((add_len >> 16) & 0xff);
3982 	buf[6] = ((add_len >> 8) & 0xff);
3983 	buf[7] = (add_len & 0xff);
3984 
3985 	transport_kunmap_data_sg(cmd);
3986 
3987 	return 0;
3988 }
3989 
3990 sense_reason_t
3991 target_scsi3_emulate_pr_in(struct se_cmd *cmd)
3992 {
3993 	sense_reason_t ret;
3994 
3995 	/*
3996 	 * Following spc2r20 5.5.1 Reservations overview:
3997 	 *
3998 	 * If a logical unit has been reserved by any RESERVE command and is
3999 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4000 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
4001 	 * initiator or service action and shall terminate with a RESERVATION
4002 	 * CONFLICT status.
4003 	 */
4004 	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
4005 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4006 			" SPC-2 reservation is held, returning"
4007 			" RESERVATION_CONFLICT\n");
4008 		return TCM_RESERVATION_CONFLICT;
4009 	}
4010 
4011 	switch (cmd->t_task_cdb[1] & 0x1f) {
4012 	case PRI_READ_KEYS:
4013 		ret = core_scsi3_pri_read_keys(cmd);
4014 		break;
4015 	case PRI_READ_RESERVATION:
4016 		ret = core_scsi3_pri_read_reservation(cmd);
4017 		break;
4018 	case PRI_REPORT_CAPABILITIES:
4019 		ret = core_scsi3_pri_report_capabilities(cmd);
4020 		break;
4021 	case PRI_READ_FULL_STATUS:
4022 		ret = core_scsi3_pri_read_full_status(cmd);
4023 		break;
4024 	default:
4025 		pr_err("Unknown PERSISTENT_RESERVE_IN service"
4026 			" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4027 		return TCM_INVALID_CDB_FIELD;
4028 	}
4029 
4030 	if (!ret)
4031 		target_complete_cmd(cmd, GOOD);
4032 	return ret;
4033 }
4034 
4035 sense_reason_t
4036 target_check_reservation(struct se_cmd *cmd)
4037 {
4038 	struct se_device *dev = cmd->se_dev;
4039 	sense_reason_t ret;
4040 
4041 	if (!cmd->se_sess)
4042 		return 0;
4043 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
4044 		return 0;
4045 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
4046 		return 0;
4047 
4048 	spin_lock(&dev->dev_reservation_lock);
4049 	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
4050 		ret = target_scsi2_reservation_check(cmd);
4051 	else
4052 		ret = target_scsi3_pr_reservation_check(cmd);
4053 	spin_unlock(&dev->dev_reservation_lock);
4054 
4055 	return ret;
4056 }
4057