xref: /linux/drivers/target/target_core_pr.c (revision 079c9534a96da9a85a2a2f9715851050fbfbf749)
1 /*******************************************************************************
2  * Filename:  target_core_pr.c
3  *
4  * This file contains SPC-3 compliant persistent reservations and
5  * legacy SPC-2 reservations with compatible reservation handling (CRH=1)
6  *
7  * Copyright (c) 2009, 2010 Rising Tide Systems
8  * Copyright (c) 2009, 2010 Linux-iSCSI.org
9  *
10  * Nicholas A. Bellinger <nab@kernel.org>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25  *
26  ******************************************************************************/
27 
28 #include <linux/slab.h>
29 #include <linux/spinlock.h>
30 #include <linux/list.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 int 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 		return 0;
63 
64 	snprintf(buf, size, ",i,0x%s", &pr_reg->pr_reg_isid[0]);
65 	return 1;
66 }
67 
68 static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
69 			struct t10_pr_registration *, int);
70 
71 static int core_scsi2_reservation_seq_non_holder(
72 	struct se_cmd *cmd,
73 	unsigned char *cdb,
74 	u32 pr_reg_type)
75 {
76 	switch (cdb[0]) {
77 	case INQUIRY:
78 	case RELEASE:
79 	case RELEASE_10:
80 		return 0;
81 	default:
82 		return 1;
83 	}
84 
85 	return 1;
86 }
87 
88 static int core_scsi2_reservation_check(struct se_cmd *cmd, u32 *pr_reg_type)
89 {
90 	struct se_device *dev = cmd->se_dev;
91 	struct se_session *sess = cmd->se_sess;
92 	int ret;
93 
94 	if (!sess)
95 		return 0;
96 
97 	spin_lock(&dev->dev_reservation_lock);
98 	if (!dev->dev_reserved_node_acl || !sess) {
99 		spin_unlock(&dev->dev_reservation_lock);
100 		return 0;
101 	}
102 	if (dev->dev_reserved_node_acl != sess->se_node_acl) {
103 		spin_unlock(&dev->dev_reservation_lock);
104 		return -EINVAL;
105 	}
106 	if (!(dev->dev_flags & DF_SPC2_RESERVATIONS_WITH_ISID)) {
107 		spin_unlock(&dev->dev_reservation_lock);
108 		return 0;
109 	}
110 	ret = (dev->dev_res_bin_isid == sess->sess_bin_isid) ? 0 : -EINVAL;
111 	spin_unlock(&dev->dev_reservation_lock);
112 
113 	return ret;
114 }
115 
116 static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
117 					struct se_node_acl *, struct se_session *);
118 static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
119 
120 static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd, int *ret)
121 {
122 	struct se_session *se_sess = cmd->se_sess;
123 	struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
124 	struct t10_pr_registration *pr_reg;
125 	struct t10_reservation *pr_tmpl = &su_dev->t10_pr;
126 	int crh = (su_dev->t10_pr.res_type == SPC3_PERSISTENT_RESERVATIONS);
127 	int conflict = 0;
128 
129 	if (!crh)
130 		return false;
131 
132 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
133 			se_sess);
134 	if (pr_reg) {
135 		/*
136 		 * From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
137 		 * behavior
138 		 *
139 		 * A RESERVE(6) or RESERVE(10) command shall complete with GOOD
140 		 * status, but no reservation shall be established and the
141 		 * persistent reservation shall not be changed, if the command
142 		 * is received from a) and b) below.
143 		 *
144 		 * A RELEASE(6) or RELEASE(10) command shall complete with GOOD
145 		 * status, but the persistent reservation shall not be released,
146 		 * if the command is received from a) and b)
147 		 *
148 		 * a) An I_T nexus that is a persistent reservation holder; or
149 		 * b) An I_T nexus that is registered if a registrants only or
150 		 *    all registrants type persistent reservation is present.
151 		 *
152 		 * In all other cases, a RESERVE(6) command, RESERVE(10) command,
153 		 * RELEASE(6) command, or RELEASE(10) command shall be processed
154 		 * as defined in SPC-2.
155 		 */
156 		if (pr_reg->pr_res_holder) {
157 			core_scsi3_put_pr_reg(pr_reg);
158 			*ret = 0;
159 			return false;
160 		}
161 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
162 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
163 		    (pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
164 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
165 			core_scsi3_put_pr_reg(pr_reg);
166 			*ret = 0;
167 			return true;
168 		}
169 		core_scsi3_put_pr_reg(pr_reg);
170 		conflict = 1;
171 	} else {
172 		/*
173 		 * Following spc2r20 5.5.1 Reservations overview:
174 		 *
175 		 * If a logical unit has executed a PERSISTENT RESERVE OUT
176 		 * command with the REGISTER or the REGISTER AND IGNORE
177 		 * EXISTING KEY service action and is still registered by any
178 		 * initiator, all RESERVE commands and all RELEASE commands
179 		 * regardless of initiator shall conflict and shall terminate
180 		 * with a RESERVATION CONFLICT status.
181 		 */
182 		spin_lock(&pr_tmpl->registration_lock);
183 		conflict = (list_empty(&pr_tmpl->registration_list)) ? 0 : 1;
184 		spin_unlock(&pr_tmpl->registration_lock);
185 	}
186 
187 	if (conflict) {
188 		pr_err("Received legacy SPC-2 RESERVE/RELEASE"
189 			" while active SPC-3 registrations exist,"
190 			" returning RESERVATION_CONFLICT\n");
191 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
192 		return true;
193 	}
194 
195 	return false;
196 }
197 
198 int target_scsi2_reservation_release(struct se_task *task)
199 {
200 	struct se_cmd *cmd = task->task_se_cmd;
201 	struct se_device *dev = cmd->se_dev;
202 	struct se_session *sess = cmd->se_sess;
203 	struct se_portal_group *tpg = sess->se_tpg;
204 	int ret = 0;
205 
206 	if (!sess || !tpg)
207 		goto out;
208 	if (target_check_scsi2_reservation_conflict(cmd, &ret))
209 		goto out;
210 
211 	ret = 0;
212 	spin_lock(&dev->dev_reservation_lock);
213 	if (!dev->dev_reserved_node_acl || !sess)
214 		goto out_unlock;
215 
216 	if (dev->dev_reserved_node_acl != sess->se_node_acl)
217 		goto out_unlock;
218 
219 	dev->dev_reserved_node_acl = NULL;
220 	dev->dev_flags &= ~DF_SPC2_RESERVATIONS;
221 	if (dev->dev_flags & DF_SPC2_RESERVATIONS_WITH_ISID) {
222 		dev->dev_res_bin_isid = 0;
223 		dev->dev_flags &= ~DF_SPC2_RESERVATIONS_WITH_ISID;
224 	}
225 	pr_debug("SCSI-2 Released reservation for %s LUN: %u ->"
226 		" MAPPED LUN: %u for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
227 		cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
228 		sess->se_node_acl->initiatorname);
229 
230 out_unlock:
231 	spin_unlock(&dev->dev_reservation_lock);
232 out:
233 	if (!ret) {
234 		task->task_scsi_status = GOOD;
235 		transport_complete_task(task, 1);
236 	}
237 	return ret;
238 }
239 
240 int target_scsi2_reservation_reserve(struct se_task *task)
241 {
242 	struct se_cmd *cmd = task->task_se_cmd;
243 	struct se_device *dev = cmd->se_dev;
244 	struct se_session *sess = cmd->se_sess;
245 	struct se_portal_group *tpg = sess->se_tpg;
246 	int ret = 0;
247 
248 	if ((cmd->t_task_cdb[1] & 0x01) &&
249 	    (cmd->t_task_cdb[1] & 0x02)) {
250 		pr_err("LongIO and Obselete Bits set, returning"
251 				" ILLEGAL_REQUEST\n");
252 		cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
253 		ret = -EINVAL;
254 		goto out;
255 	}
256 	/*
257 	 * This is currently the case for target_core_mod passthrough struct se_cmd
258 	 * ops
259 	 */
260 	if (!sess || !tpg)
261 		goto out;
262 	if (target_check_scsi2_reservation_conflict(cmd, &ret))
263 		goto out;
264 
265 	ret = 0;
266 	spin_lock(&dev->dev_reservation_lock);
267 	if (dev->dev_reserved_node_acl &&
268 	   (dev->dev_reserved_node_acl != sess->se_node_acl)) {
269 		pr_err("SCSI-2 RESERVATION CONFLIFT for %s fabric\n",
270 			tpg->se_tpg_tfo->get_fabric_name());
271 		pr_err("Original reserver LUN: %u %s\n",
272 			cmd->se_lun->unpacked_lun,
273 			dev->dev_reserved_node_acl->initiatorname);
274 		pr_err("Current attempt - LUN: %u -> MAPPED LUN: %u"
275 			" from %s \n", cmd->se_lun->unpacked_lun,
276 			cmd->se_deve->mapped_lun,
277 			sess->se_node_acl->initiatorname);
278 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
279 		ret = -EINVAL;
280 		goto out_unlock;
281 	}
282 
283 	dev->dev_reserved_node_acl = sess->se_node_acl;
284 	dev->dev_flags |= DF_SPC2_RESERVATIONS;
285 	if (sess->sess_bin_isid != 0) {
286 		dev->dev_res_bin_isid = sess->sess_bin_isid;
287 		dev->dev_flags |= DF_SPC2_RESERVATIONS_WITH_ISID;
288 	}
289 	pr_debug("SCSI-2 Reserved %s LUN: %u -> MAPPED LUN: %u"
290 		" for %s\n", tpg->se_tpg_tfo->get_fabric_name(),
291 		cmd->se_lun->unpacked_lun, cmd->se_deve->mapped_lun,
292 		sess->se_node_acl->initiatorname);
293 
294 out_unlock:
295 	spin_unlock(&dev->dev_reservation_lock);
296 out:
297 	if (!ret) {
298 		task->task_scsi_status = GOOD;
299 		transport_complete_task(task, 1);
300 	}
301 	return ret;
302 }
303 
304 
305 /*
306  * Begin SPC-3/SPC-4 Persistent Reservations emulation support
307  *
308  * This function is called by those initiator ports who are *NOT*
309  * the active PR reservation holder when a reservation is present.
310  */
311 static int core_scsi3_pr_seq_non_holder(
312 	struct se_cmd *cmd,
313 	unsigned char *cdb,
314 	u32 pr_reg_type)
315 {
316 	struct se_dev_entry *se_deve;
317 	struct se_session *se_sess = cmd->se_sess;
318 	int other_cdb = 0, ignore_reg;
319 	int registered_nexus = 0, ret = 1; /* Conflict by default */
320 	int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
321 	int we = 0; /* Write Exclusive */
322 	int legacy = 0; /* Act like a legacy device and return
323 			 * RESERVATION CONFLICT on some CDBs */
324 	/*
325 	 * A legacy SPC-2 reservation is being held.
326 	 */
327 	if (cmd->se_dev->dev_flags & DF_SPC2_RESERVATIONS)
328 		return core_scsi2_reservation_seq_non_holder(cmd,
329 					cdb, pr_reg_type);
330 
331 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
332 	/*
333 	 * Determine if the registration should be ignored due to
334 	 * non-matching ISIDs in core_scsi3_pr_reservation_check().
335 	 */
336 	ignore_reg = (pr_reg_type & 0x80000000);
337 	if (ignore_reg)
338 		pr_reg_type &= ~0x80000000;
339 
340 	switch (pr_reg_type) {
341 	case PR_TYPE_WRITE_EXCLUSIVE:
342 		we = 1;
343 	case PR_TYPE_EXCLUSIVE_ACCESS:
344 		/*
345 		 * Some commands are only allowed for the persistent reservation
346 		 * holder.
347 		 */
348 		if ((se_deve->def_pr_registered) && !(ignore_reg))
349 			registered_nexus = 1;
350 		break;
351 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
352 		we = 1;
353 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
354 		/*
355 		 * Some commands are only allowed for registered I_T Nexuses.
356 		 */
357 		reg_only = 1;
358 		if ((se_deve->def_pr_registered) && !(ignore_reg))
359 			registered_nexus = 1;
360 		break;
361 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
362 		we = 1;
363 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
364 		/*
365 		 * Each registered I_T Nexus is a reservation holder.
366 		 */
367 		all_reg = 1;
368 		if ((se_deve->def_pr_registered) && !(ignore_reg))
369 			registered_nexus = 1;
370 		break;
371 	default:
372 		return -EINVAL;
373 	}
374 	/*
375 	 * Referenced from spc4r17 table 45 for *NON* PR holder access
376 	 */
377 	switch (cdb[0]) {
378 	case SECURITY_PROTOCOL_IN:
379 		if (registered_nexus)
380 			return 0;
381 		ret = (we) ? 0 : 1;
382 		break;
383 	case MODE_SENSE:
384 	case MODE_SENSE_10:
385 	case READ_ATTRIBUTE:
386 	case READ_BUFFER:
387 	case RECEIVE_DIAGNOSTIC:
388 		if (legacy) {
389 			ret = 1;
390 			break;
391 		}
392 		if (registered_nexus) {
393 			ret = 0;
394 			break;
395 		}
396 		ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
397 		break;
398 	case PERSISTENT_RESERVE_OUT:
399 		/*
400 		 * This follows PERSISTENT_RESERVE_OUT service actions that
401 		 * are allowed in the presence of various reservations.
402 		 * See spc4r17, table 46
403 		 */
404 		switch (cdb[1] & 0x1f) {
405 		case PRO_CLEAR:
406 		case PRO_PREEMPT:
407 		case PRO_PREEMPT_AND_ABORT:
408 			ret = (registered_nexus) ? 0 : 1;
409 			break;
410 		case PRO_REGISTER:
411 		case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
412 			ret = 0;
413 			break;
414 		case PRO_REGISTER_AND_MOVE:
415 		case PRO_RESERVE:
416 			ret = 1;
417 			break;
418 		case PRO_RELEASE:
419 			ret = (registered_nexus) ? 0 : 1;
420 			break;
421 		default:
422 			pr_err("Unknown PERSISTENT_RESERVE_OUT service"
423 				" action: 0x%02x\n", cdb[1] & 0x1f);
424 			return -EINVAL;
425 		}
426 		break;
427 	case RELEASE:
428 	case RELEASE_10:
429 		/* Handled by CRH=1 in target_scsi2_reservation_release() */
430 		ret = 0;
431 		break;
432 	case RESERVE:
433 	case RESERVE_10:
434 		/* Handled by CRH=1 in target_scsi2_reservation_reserve() */
435 		ret = 0;
436 		break;
437 	case TEST_UNIT_READY:
438 		ret = (legacy) ? 1 : 0; /* Conflict for legacy */
439 		break;
440 	case MAINTENANCE_IN:
441 		switch (cdb[1] & 0x1f) {
442 		case MI_MANAGEMENT_PROTOCOL_IN:
443 			if (registered_nexus) {
444 				ret = 0;
445 				break;
446 			}
447 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
448 			break;
449 		case MI_REPORT_SUPPORTED_OPERATION_CODES:
450 		case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
451 			if (legacy) {
452 				ret = 1;
453 				break;
454 			}
455 			if (registered_nexus) {
456 				ret = 0;
457 				break;
458 			}
459 			ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
460 			break;
461 		case MI_REPORT_ALIASES:
462 		case MI_REPORT_IDENTIFYING_INFORMATION:
463 		case MI_REPORT_PRIORITY:
464 		case MI_REPORT_TARGET_PGS:
465 		case MI_REPORT_TIMESTAMP:
466 			ret = 0; /* Allowed */
467 			break;
468 		default:
469 			pr_err("Unknown MI Service Action: 0x%02x\n",
470 				(cdb[1] & 0x1f));
471 			return -EINVAL;
472 		}
473 		break;
474 	case ACCESS_CONTROL_IN:
475 	case ACCESS_CONTROL_OUT:
476 	case INQUIRY:
477 	case LOG_SENSE:
478 	case READ_MEDIA_SERIAL_NUMBER:
479 	case REPORT_LUNS:
480 	case REQUEST_SENSE:
481 	case PERSISTENT_RESERVE_IN:
482 		ret = 0; /*/ Allowed CDBs */
483 		break;
484 	default:
485 		other_cdb = 1;
486 		break;
487 	}
488 	/*
489 	 * Case where the CDB is explicitly allowed in the above switch
490 	 * statement.
491 	 */
492 	if (!ret && !other_cdb) {
493 #if 0
494 		pr_debug("Allowing explict CDB: 0x%02x for %s"
495 			" reservation holder\n", cdb[0],
496 			core_scsi3_pr_dump_type(pr_reg_type));
497 #endif
498 		return ret;
499 	}
500 	/*
501 	 * Check if write exclusive initiator ports *NOT* holding the
502 	 * WRITE_EXCLUSIVE_* reservation.
503 	 */
504 	if ((we) && !(registered_nexus)) {
505 		if (cmd->data_direction == DMA_TO_DEVICE) {
506 			/*
507 			 * Conflict for write exclusive
508 			 */
509 			pr_debug("%s Conflict for unregistered nexus"
510 				" %s CDB: 0x%02x to %s reservation\n",
511 				transport_dump_cmd_direction(cmd),
512 				se_sess->se_node_acl->initiatorname, cdb[0],
513 				core_scsi3_pr_dump_type(pr_reg_type));
514 			return 1;
515 		} else {
516 			/*
517 			 * Allow non WRITE CDBs for all Write Exclusive
518 			 * PR TYPEs to pass for registered and
519 			 * non-registered_nexuxes NOT holding the reservation.
520 			 *
521 			 * We only make noise for the unregisterd nexuses,
522 			 * as we expect registered non-reservation holding
523 			 * nexuses to issue CDBs.
524 			 */
525 #if 0
526 			if (!registered_nexus) {
527 				pr_debug("Allowing implict CDB: 0x%02x"
528 					" for %s reservation on unregistered"
529 					" nexus\n", cdb[0],
530 					core_scsi3_pr_dump_type(pr_reg_type));
531 			}
532 #endif
533 			return 0;
534 		}
535 	} else if ((reg_only) || (all_reg)) {
536 		if (registered_nexus) {
537 			/*
538 			 * For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
539 			 * allow commands from registered nexuses.
540 			 */
541 #if 0
542 			pr_debug("Allowing implict CDB: 0x%02x for %s"
543 				" reservation\n", cdb[0],
544 				core_scsi3_pr_dump_type(pr_reg_type));
545 #endif
546 			return 0;
547 		}
548 	}
549 	pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
550 		" for %s reservation\n", transport_dump_cmd_direction(cmd),
551 		(registered_nexus) ? "" : "un",
552 		se_sess->se_node_acl->initiatorname, cdb[0],
553 		core_scsi3_pr_dump_type(pr_reg_type));
554 
555 	return 1; /* Conflict by default */
556 }
557 
558 static u32 core_scsi3_pr_generation(struct se_device *dev)
559 {
560 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
561 	u32 prg;
562 	/*
563 	 * PRGeneration field shall contain the value of a 32-bit wrapping
564 	 * counter mainted by the device server.
565 	 *
566 	 * Note that this is done regardless of Active Persist across
567 	 * Target PowerLoss (APTPL)
568 	 *
569 	 * See spc4r17 section 6.3.12 READ_KEYS service action
570 	 */
571 	spin_lock(&dev->dev_reservation_lock);
572 	prg = su_dev->t10_pr.pr_generation++;
573 	spin_unlock(&dev->dev_reservation_lock);
574 
575 	return prg;
576 }
577 
578 static int core_scsi3_pr_reservation_check(
579 	struct se_cmd *cmd,
580 	u32 *pr_reg_type)
581 {
582 	struct se_device *dev = cmd->se_dev;
583 	struct se_session *sess = cmd->se_sess;
584 	int ret;
585 
586 	if (!sess)
587 		return 0;
588 	/*
589 	 * A legacy SPC-2 reservation is being held.
590 	 */
591 	if (dev->dev_flags & DF_SPC2_RESERVATIONS)
592 		return core_scsi2_reservation_check(cmd, pr_reg_type);
593 
594 	spin_lock(&dev->dev_reservation_lock);
595 	if (!dev->dev_pr_res_holder) {
596 		spin_unlock(&dev->dev_reservation_lock);
597 		return 0;
598 	}
599 	*pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
600 	cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
601 	if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl) {
602 		spin_unlock(&dev->dev_reservation_lock);
603 		return -EINVAL;
604 	}
605 	if (!dev->dev_pr_res_holder->isid_present_at_reg) {
606 		spin_unlock(&dev->dev_reservation_lock);
607 		return 0;
608 	}
609 	ret = (dev->dev_pr_res_holder->pr_reg_bin_isid ==
610 	       sess->sess_bin_isid) ? 0 : -EINVAL;
611 	/*
612 	 * Use bit in *pr_reg_type to notify ISID mismatch in
613 	 * core_scsi3_pr_seq_non_holder().
614 	 */
615 	if (ret != 0)
616 		*pr_reg_type |= 0x80000000;
617 	spin_unlock(&dev->dev_reservation_lock);
618 
619 	return ret;
620 }
621 
622 static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
623 	struct se_device *dev,
624 	struct se_node_acl *nacl,
625 	struct se_dev_entry *deve,
626 	unsigned char *isid,
627 	u64 sa_res_key,
628 	int all_tg_pt,
629 	int aptpl)
630 {
631 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
632 	struct t10_pr_registration *pr_reg;
633 
634 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_ATOMIC);
635 	if (!pr_reg) {
636 		pr_err("Unable to allocate struct t10_pr_registration\n");
637 		return NULL;
638 	}
639 
640 	pr_reg->pr_aptpl_buf = kzalloc(su_dev->t10_pr.pr_aptpl_buf_len,
641 					GFP_ATOMIC);
642 	if (!pr_reg->pr_aptpl_buf) {
643 		pr_err("Unable to allocate pr_reg->pr_aptpl_buf\n");
644 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
645 		return NULL;
646 	}
647 
648 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
649 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
650 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
651 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
652 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
653 	atomic_set(&pr_reg->pr_res_holders, 0);
654 	pr_reg->pr_reg_nacl = nacl;
655 	pr_reg->pr_reg_deve = deve;
656 	pr_reg->pr_res_mapped_lun = deve->mapped_lun;
657 	pr_reg->pr_aptpl_target_lun = deve->se_lun->unpacked_lun;
658 	pr_reg->pr_res_key = sa_res_key;
659 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
660 	pr_reg->pr_reg_aptpl = aptpl;
661 	pr_reg->pr_reg_tg_pt_lun = deve->se_lun;
662 	/*
663 	 * If an ISID value for this SCSI Initiator Port exists,
664 	 * save it to the registration now.
665 	 */
666 	if (isid != NULL) {
667 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
668 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
669 		pr_reg->isid_present_at_reg = 1;
670 	}
671 
672 	return pr_reg;
673 }
674 
675 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
676 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
677 
678 /*
679  * Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
680  * modes.
681  */
682 static struct t10_pr_registration *__core_scsi3_alloc_registration(
683 	struct se_device *dev,
684 	struct se_node_acl *nacl,
685 	struct se_dev_entry *deve,
686 	unsigned char *isid,
687 	u64 sa_res_key,
688 	int all_tg_pt,
689 	int aptpl)
690 {
691 	struct se_dev_entry *deve_tmp;
692 	struct se_node_acl *nacl_tmp;
693 	struct se_port *port, *port_tmp;
694 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
695 	struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
696 	int ret;
697 	/*
698 	 * Create a registration for the I_T Nexus upon which the
699 	 * PROUT REGISTER was received.
700 	 */
701 	pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, deve, isid,
702 			sa_res_key, all_tg_pt, aptpl);
703 	if (!pr_reg)
704 		return NULL;
705 	/*
706 	 * Return pointer to pr_reg for ALL_TG_PT=0
707 	 */
708 	if (!all_tg_pt)
709 		return pr_reg;
710 	/*
711 	 * Create list of matching SCSI Initiator Port registrations
712 	 * for ALL_TG_PT=1
713 	 */
714 	spin_lock(&dev->se_port_lock);
715 	list_for_each_entry_safe(port, port_tmp, &dev->dev_sep_list, sep_list) {
716 		atomic_inc(&port->sep_tg_pt_ref_cnt);
717 		smp_mb__after_atomic_inc();
718 		spin_unlock(&dev->se_port_lock);
719 
720 		spin_lock_bh(&port->sep_alua_lock);
721 		list_for_each_entry(deve_tmp, &port->sep_alua_list,
722 					alua_port_list) {
723 			/*
724 			 * This pointer will be NULL for demo mode MappedLUNs
725 			 * that have not been make explict via a ConfigFS
726 			 * MappedLUN group for the SCSI Initiator Node ACL.
727 			 */
728 			if (!deve_tmp->se_lun_acl)
729 				continue;
730 
731 			nacl_tmp = deve_tmp->se_lun_acl->se_lun_nacl;
732 			/*
733 			 * Skip the matching struct se_node_acl that is allocated
734 			 * above..
735 			 */
736 			if (nacl == nacl_tmp)
737 				continue;
738 			/*
739 			 * Only perform PR registrations for target ports on
740 			 * the same fabric module as the REGISTER w/ ALL_TG_PT=1
741 			 * arrived.
742 			 */
743 			if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
744 				continue;
745 			/*
746 			 * Look for a matching Initiator Node ACL in ASCII format
747 			 */
748 			if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
749 				continue;
750 
751 			atomic_inc(&deve_tmp->pr_ref_count);
752 			smp_mb__after_atomic_inc();
753 			spin_unlock_bh(&port->sep_alua_lock);
754 			/*
755 			 * Grab a configfs group dependency that is released
756 			 * for the exception path at label out: below, or upon
757 			 * completion of adding ALL_TG_PT=1 registrations in
758 			 * __core_scsi3_add_registration()
759 			 */
760 			ret = core_scsi3_lunacl_depend_item(deve_tmp);
761 			if (ret < 0) {
762 				pr_err("core_scsi3_lunacl_depend"
763 						"_item() failed\n");
764 				atomic_dec(&port->sep_tg_pt_ref_cnt);
765 				smp_mb__after_atomic_dec();
766 				atomic_dec(&deve_tmp->pr_ref_count);
767 				smp_mb__after_atomic_dec();
768 				goto out;
769 			}
770 			/*
771 			 * Located a matching SCSI Initiator Port on a different
772 			 * port, allocate the pr_reg_atp and attach it to the
773 			 * pr_reg->pr_reg_atp_list that will be processed once
774 			 * the original *pr_reg is processed in
775 			 * __core_scsi3_add_registration()
776 			 */
777 			pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
778 						nacl_tmp, deve_tmp, NULL,
779 						sa_res_key, all_tg_pt, aptpl);
780 			if (!pr_reg_atp) {
781 				atomic_dec(&port->sep_tg_pt_ref_cnt);
782 				smp_mb__after_atomic_dec();
783 				atomic_dec(&deve_tmp->pr_ref_count);
784 				smp_mb__after_atomic_dec();
785 				core_scsi3_lunacl_undepend_item(deve_tmp);
786 				goto out;
787 			}
788 
789 			list_add_tail(&pr_reg_atp->pr_reg_atp_mem_list,
790 				      &pr_reg->pr_reg_atp_list);
791 			spin_lock_bh(&port->sep_alua_lock);
792 		}
793 		spin_unlock_bh(&port->sep_alua_lock);
794 
795 		spin_lock(&dev->se_port_lock);
796 		atomic_dec(&port->sep_tg_pt_ref_cnt);
797 		smp_mb__after_atomic_dec();
798 	}
799 	spin_unlock(&dev->se_port_lock);
800 
801 	return pr_reg;
802 out:
803 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
804 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
805 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
806 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
807 		kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
808 	}
809 	kmem_cache_free(t10_pr_reg_cache, pr_reg);
810 	return NULL;
811 }
812 
813 int core_scsi3_alloc_aptpl_registration(
814 	struct t10_reservation *pr_tmpl,
815 	u64 sa_res_key,
816 	unsigned char *i_port,
817 	unsigned char *isid,
818 	u32 mapped_lun,
819 	unsigned char *t_port,
820 	u16 tpgt,
821 	u32 target_lun,
822 	int res_holder,
823 	int all_tg_pt,
824 	u8 type)
825 {
826 	struct t10_pr_registration *pr_reg;
827 
828 	if (!i_port || !t_port || !sa_res_key) {
829 		pr_err("Illegal parameters for APTPL registration\n");
830 		return -EINVAL;
831 	}
832 
833 	pr_reg = kmem_cache_zalloc(t10_pr_reg_cache, GFP_KERNEL);
834 	if (!pr_reg) {
835 		pr_err("Unable to allocate struct t10_pr_registration\n");
836 		return -ENOMEM;
837 	}
838 	pr_reg->pr_aptpl_buf = kzalloc(pr_tmpl->pr_aptpl_buf_len, GFP_KERNEL);
839 
840 	INIT_LIST_HEAD(&pr_reg->pr_reg_list);
841 	INIT_LIST_HEAD(&pr_reg->pr_reg_abort_list);
842 	INIT_LIST_HEAD(&pr_reg->pr_reg_aptpl_list);
843 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_list);
844 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
845 	atomic_set(&pr_reg->pr_res_holders, 0);
846 	pr_reg->pr_reg_nacl = NULL;
847 	pr_reg->pr_reg_deve = NULL;
848 	pr_reg->pr_res_mapped_lun = mapped_lun;
849 	pr_reg->pr_aptpl_target_lun = target_lun;
850 	pr_reg->pr_res_key = sa_res_key;
851 	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
852 	pr_reg->pr_reg_aptpl = 1;
853 	pr_reg->pr_reg_tg_pt_lun = NULL;
854 	pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
855 	pr_reg->pr_res_type = type;
856 	/*
857 	 * If an ISID value had been saved in APTPL metadata for this
858 	 * SCSI Initiator Port, restore it now.
859 	 */
860 	if (isid != NULL) {
861 		pr_reg->pr_reg_bin_isid = get_unaligned_be64(isid);
862 		snprintf(pr_reg->pr_reg_isid, PR_REG_ISID_LEN, "%s", isid);
863 		pr_reg->isid_present_at_reg = 1;
864 	}
865 	/*
866 	 * Copy the i_port and t_port information from caller.
867 	 */
868 	snprintf(pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, "%s", i_port);
869 	snprintf(pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, "%s", t_port);
870 	pr_reg->pr_reg_tpgt = tpgt;
871 	/*
872 	 * Set pr_res_holder from caller, the pr_reg who is the reservation
873 	 * holder will get it's pointer set in core_scsi3_aptpl_reserve() once
874 	 * the Initiator Node LUN ACL from the fabric module is created for
875 	 * this registration.
876 	 */
877 	pr_reg->pr_res_holder = res_holder;
878 
879 	list_add_tail(&pr_reg->pr_reg_aptpl_list, &pr_tmpl->aptpl_reg_list);
880 	pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
881 			" metadata\n", (res_holder) ? "+reservation" : "");
882 	return 0;
883 }
884 
885 static void core_scsi3_aptpl_reserve(
886 	struct se_device *dev,
887 	struct se_portal_group *tpg,
888 	struct se_node_acl *node_acl,
889 	struct t10_pr_registration *pr_reg)
890 {
891 	char i_buf[PR_REG_ISID_ID_LEN];
892 	int prf_isid;
893 
894 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
895 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
896 				PR_REG_ISID_ID_LEN);
897 
898 	spin_lock(&dev->dev_reservation_lock);
899 	dev->dev_pr_res_holder = pr_reg;
900 	spin_unlock(&dev->dev_reservation_lock);
901 
902 	pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
903 		" new reservation holder TYPE: %s ALL_TG_PT: %d\n",
904 		tpg->se_tpg_tfo->get_fabric_name(),
905 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
906 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
907 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
908 		tpg->se_tpg_tfo->get_fabric_name(), node_acl->initiatorname,
909 		(prf_isid) ? &i_buf[0] : "");
910 }
911 
912 static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
913 				struct t10_pr_registration *, int, int);
914 
915 static int __core_scsi3_check_aptpl_registration(
916 	struct se_device *dev,
917 	struct se_portal_group *tpg,
918 	struct se_lun *lun,
919 	u32 target_lun,
920 	struct se_node_acl *nacl,
921 	struct se_dev_entry *deve)
922 {
923 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
924 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
925 	unsigned char i_port[PR_APTPL_MAX_IPORT_LEN];
926 	unsigned char t_port[PR_APTPL_MAX_TPORT_LEN];
927 	u16 tpgt;
928 
929 	memset(i_port, 0, PR_APTPL_MAX_IPORT_LEN);
930 	memset(t_port, 0, PR_APTPL_MAX_TPORT_LEN);
931 	/*
932 	 * Copy Initiator Port information from struct se_node_acl
933 	 */
934 	snprintf(i_port, PR_APTPL_MAX_IPORT_LEN, "%s", nacl->initiatorname);
935 	snprintf(t_port, PR_APTPL_MAX_TPORT_LEN, "%s",
936 			tpg->se_tpg_tfo->tpg_get_wwn(tpg));
937 	tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
938 	/*
939 	 * Look for the matching registrations+reservation from those
940 	 * created from APTPL metadata.  Note that multiple registrations
941 	 * may exist for fabrics that use ISIDs in their SCSI Initiator Port
942 	 * TransportIDs.
943 	 */
944 	spin_lock(&pr_tmpl->aptpl_reg_lock);
945 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
946 				pr_reg_aptpl_list) {
947 		if (!strcmp(pr_reg->pr_iport, i_port) &&
948 		     (pr_reg->pr_res_mapped_lun == deve->mapped_lun) &&
949 		    !(strcmp(pr_reg->pr_tport, t_port)) &&
950 		     (pr_reg->pr_reg_tpgt == tpgt) &&
951 		     (pr_reg->pr_aptpl_target_lun == target_lun)) {
952 
953 			pr_reg->pr_reg_nacl = nacl;
954 			pr_reg->pr_reg_deve = deve;
955 			pr_reg->pr_reg_tg_pt_lun = lun;
956 
957 			list_del(&pr_reg->pr_reg_aptpl_list);
958 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
959 			/*
960 			 * At this point all of the pointers in *pr_reg will
961 			 * be setup, so go ahead and add the registration.
962 			 */
963 
964 			__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
965 			/*
966 			 * If this registration is the reservation holder,
967 			 * make that happen now..
968 			 */
969 			if (pr_reg->pr_res_holder)
970 				core_scsi3_aptpl_reserve(dev, tpg,
971 						nacl, pr_reg);
972 			/*
973 			 * Reenable pr_aptpl_active to accept new metadata
974 			 * updates once the SCSI device is active again..
975 			 */
976 			spin_lock(&pr_tmpl->aptpl_reg_lock);
977 			pr_tmpl->pr_aptpl_active = 1;
978 		}
979 	}
980 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
981 
982 	return 0;
983 }
984 
985 int core_scsi3_check_aptpl_registration(
986 	struct se_device *dev,
987 	struct se_portal_group *tpg,
988 	struct se_lun *lun,
989 	struct se_lun_acl *lun_acl)
990 {
991 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
992 	struct se_node_acl *nacl = lun_acl->se_lun_nacl;
993 	struct se_dev_entry *deve = &nacl->device_list[lun_acl->mapped_lun];
994 
995 	if (su_dev->t10_pr.res_type != SPC3_PERSISTENT_RESERVATIONS)
996 		return 0;
997 
998 	return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
999 				lun->unpacked_lun, nacl, deve);
1000 }
1001 
1002 static void __core_scsi3_dump_registration(
1003 	struct target_core_fabric_ops *tfo,
1004 	struct se_device *dev,
1005 	struct se_node_acl *nacl,
1006 	struct t10_pr_registration *pr_reg,
1007 	int register_type)
1008 {
1009 	struct se_portal_group *se_tpg = nacl->se_tpg;
1010 	char i_buf[PR_REG_ISID_ID_LEN];
1011 	int prf_isid;
1012 
1013 	memset(&i_buf[0], 0, PR_REG_ISID_ID_LEN);
1014 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
1015 				PR_REG_ISID_ID_LEN);
1016 
1017 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
1018 		" Node: %s%s\n", tfo->get_fabric_name(), (register_type == 2) ?
1019 		"_AND_MOVE" : (register_type == 1) ?
1020 		"_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
1021 		(prf_isid) ? i_buf : "");
1022 	pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
1023 		 tfo->get_fabric_name(), tfo->tpg_get_wwn(se_tpg),
1024 		tfo->tpg_get_tag(se_tpg));
1025 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1026 		" Port(s)\n",  tfo->get_fabric_name(),
1027 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1028 		dev->transport->name);
1029 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1030 		" 0x%08x  APTPL: %d\n", tfo->get_fabric_name(),
1031 		pr_reg->pr_res_key, pr_reg->pr_res_generation,
1032 		pr_reg->pr_reg_aptpl);
1033 }
1034 
1035 /*
1036  * this function can be called with struct se_device->dev_reservation_lock
1037  * when register_move = 1
1038  */
1039 static void __core_scsi3_add_registration(
1040 	struct se_device *dev,
1041 	struct se_node_acl *nacl,
1042 	struct t10_pr_registration *pr_reg,
1043 	int register_type,
1044 	int register_move)
1045 {
1046 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1047 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1048 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1049 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1050 
1051 	/*
1052 	 * Increment PRgeneration counter for struct se_device upon a successful
1053 	 * REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1054 	 *
1055 	 * Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1056 	 * action, the struct se_device->dev_reservation_lock will already be held,
1057 	 * so we do not call core_scsi3_pr_generation() which grabs the lock
1058 	 * for the REGISTER.
1059 	 */
1060 	pr_reg->pr_res_generation = (register_move) ?
1061 			su_dev->t10_pr.pr_generation++ :
1062 			core_scsi3_pr_generation(dev);
1063 
1064 	spin_lock(&pr_tmpl->registration_lock);
1065 	list_add_tail(&pr_reg->pr_reg_list, &pr_tmpl->registration_list);
1066 	pr_reg->pr_reg_deve->def_pr_registered = 1;
1067 
1068 	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1069 	spin_unlock(&pr_tmpl->registration_lock);
1070 	/*
1071 	 * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1072 	 */
1073 	if (!pr_reg->pr_reg_all_tg_pt || register_move)
1074 		return;
1075 	/*
1076 	 * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1077 	 * allocated in __core_scsi3_alloc_registration()
1078 	 */
1079 	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1080 			&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1081 		list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1082 
1083 		pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1084 
1085 		spin_lock(&pr_tmpl->registration_lock);
1086 		list_add_tail(&pr_reg_tmp->pr_reg_list,
1087 			      &pr_tmpl->registration_list);
1088 		pr_reg_tmp->pr_reg_deve->def_pr_registered = 1;
1089 
1090 		__core_scsi3_dump_registration(tfo, dev,
1091 				pr_reg_tmp->pr_reg_nacl, pr_reg_tmp,
1092 				register_type);
1093 		spin_unlock(&pr_tmpl->registration_lock);
1094 		/*
1095 		 * Drop configfs group dependency reference from
1096 		 * __core_scsi3_alloc_registration()
1097 		 */
1098 		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1099 	}
1100 }
1101 
1102 static int core_scsi3_alloc_registration(
1103 	struct se_device *dev,
1104 	struct se_node_acl *nacl,
1105 	struct se_dev_entry *deve,
1106 	unsigned char *isid,
1107 	u64 sa_res_key,
1108 	int all_tg_pt,
1109 	int aptpl,
1110 	int register_type,
1111 	int register_move)
1112 {
1113 	struct t10_pr_registration *pr_reg;
1114 
1115 	pr_reg = __core_scsi3_alloc_registration(dev, nacl, deve, isid,
1116 			sa_res_key, all_tg_pt, aptpl);
1117 	if (!pr_reg)
1118 		return -EPERM;
1119 
1120 	__core_scsi3_add_registration(dev, nacl, pr_reg,
1121 			register_type, register_move);
1122 	return 0;
1123 }
1124 
1125 static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1126 	struct se_device *dev,
1127 	struct se_node_acl *nacl,
1128 	unsigned char *isid)
1129 {
1130 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1131 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1132 	struct se_portal_group *tpg;
1133 
1134 	spin_lock(&pr_tmpl->registration_lock);
1135 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1136 			&pr_tmpl->registration_list, pr_reg_list) {
1137 		/*
1138 		 * First look for a matching struct se_node_acl
1139 		 */
1140 		if (pr_reg->pr_reg_nacl != nacl)
1141 			continue;
1142 
1143 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1144 		/*
1145 		 * If this registration does NOT contain a fabric provided
1146 		 * ISID, then we have found a match.
1147 		 */
1148 		if (!pr_reg->isid_present_at_reg) {
1149 			/*
1150 			 * Determine if this SCSI device server requires that
1151 			 * SCSI Intiatior TransportID w/ ISIDs is enforced
1152 			 * for fabric modules (iSCSI) requiring them.
1153 			 */
1154 			if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1155 				if (dev->se_sub_dev->se_dev_attrib.enforce_pr_isids)
1156 					continue;
1157 			}
1158 			atomic_inc(&pr_reg->pr_res_holders);
1159 			smp_mb__after_atomic_inc();
1160 			spin_unlock(&pr_tmpl->registration_lock);
1161 			return pr_reg;
1162 		}
1163 		/*
1164 		 * If the *pr_reg contains a fabric defined ISID for multi-value
1165 		 * SCSI Initiator Port TransportIDs, then we expect a valid
1166 		 * matching ISID to be provided by the local SCSI Initiator Port.
1167 		 */
1168 		if (!isid)
1169 			continue;
1170 		if (strcmp(isid, pr_reg->pr_reg_isid))
1171 			continue;
1172 
1173 		atomic_inc(&pr_reg->pr_res_holders);
1174 		smp_mb__after_atomic_inc();
1175 		spin_unlock(&pr_tmpl->registration_lock);
1176 		return pr_reg;
1177 	}
1178 	spin_unlock(&pr_tmpl->registration_lock);
1179 
1180 	return NULL;
1181 }
1182 
1183 static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1184 	struct se_device *dev,
1185 	struct se_node_acl *nacl,
1186 	struct se_session *sess)
1187 {
1188 	struct se_portal_group *tpg = nacl->se_tpg;
1189 	unsigned char buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
1190 
1191 	if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1192 		memset(&buf[0], 0, PR_REG_ISID_LEN);
1193 		tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1194 					PR_REG_ISID_LEN);
1195 		isid_ptr = &buf[0];
1196 	}
1197 
1198 	return __core_scsi3_locate_pr_reg(dev, nacl, isid_ptr);
1199 }
1200 
1201 static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1202 {
1203 	atomic_dec(&pr_reg->pr_res_holders);
1204 	smp_mb__after_atomic_dec();
1205 }
1206 
1207 static int core_scsi3_check_implict_release(
1208 	struct se_device *dev,
1209 	struct t10_pr_registration *pr_reg)
1210 {
1211 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1212 	struct t10_pr_registration *pr_res_holder;
1213 	int ret = 0;
1214 
1215 	spin_lock(&dev->dev_reservation_lock);
1216 	pr_res_holder = dev->dev_pr_res_holder;
1217 	if (!pr_res_holder) {
1218 		spin_unlock(&dev->dev_reservation_lock);
1219 		return ret;
1220 	}
1221 	if (pr_res_holder == pr_reg) {
1222 		/*
1223 		 * Perform an implict RELEASE if the registration that
1224 		 * is being released is holding the reservation.
1225 		 *
1226 		 * From spc4r17, section 5.7.11.1:
1227 		 *
1228 		 * e) If the I_T nexus is the persistent reservation holder
1229 		 *    and the persistent reservation is not an all registrants
1230 		 *    type, then a PERSISTENT RESERVE OUT command with REGISTER
1231 		 *    service action or REGISTER AND  IGNORE EXISTING KEY
1232 		 *    service action with the SERVICE ACTION RESERVATION KEY
1233 		 *    field set to zero (see 5.7.11.3).
1234 		 */
1235 		__core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0);
1236 		ret = 1;
1237 		/*
1238 		 * For 'All Registrants' reservation types, all existing
1239 		 * registrations are still processed as reservation holders
1240 		 * in core_scsi3_pr_seq_non_holder() after the initial
1241 		 * reservation holder is implictly released here.
1242 		 */
1243 	} else if (pr_reg->pr_reg_all_tg_pt &&
1244 		  (!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1245 			  pr_reg->pr_reg_nacl->initiatorname)) &&
1246 		  (pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1247 		pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1248 			" UNREGISTER while existing reservation with matching"
1249 			" key 0x%016Lx is present from another SCSI Initiator"
1250 			" Port\n", pr_reg->pr_res_key);
1251 		ret = -EPERM;
1252 	}
1253 	spin_unlock(&dev->dev_reservation_lock);
1254 
1255 	return ret;
1256 }
1257 
1258 /*
1259  * Called with struct t10_reservation->registration_lock held.
1260  */
1261 static void __core_scsi3_free_registration(
1262 	struct se_device *dev,
1263 	struct t10_pr_registration *pr_reg,
1264 	struct list_head *preempt_and_abort_list,
1265 	int dec_holders)
1266 {
1267 	struct target_core_fabric_ops *tfo =
1268 			pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1269 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1270 	char i_buf[PR_REG_ISID_ID_LEN];
1271 	int prf_isid;
1272 
1273 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1274 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
1275 				PR_REG_ISID_ID_LEN);
1276 
1277 	pr_reg->pr_reg_deve->def_pr_registered = 0;
1278 	pr_reg->pr_reg_deve->pr_res_key = 0;
1279 	list_del(&pr_reg->pr_reg_list);
1280 	/*
1281 	 * Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1282 	 * so call core_scsi3_put_pr_reg() to decrement our reference.
1283 	 */
1284 	if (dec_holders)
1285 		core_scsi3_put_pr_reg(pr_reg);
1286 	/*
1287 	 * Wait until all reference from any other I_T nexuses for this
1288 	 * *pr_reg have been released.  Because list_del() is called above,
1289 	 * the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1290 	 * count back to zero, and we release *pr_reg.
1291 	 */
1292 	while (atomic_read(&pr_reg->pr_res_holders) != 0) {
1293 		spin_unlock(&pr_tmpl->registration_lock);
1294 		pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1295 				tfo->get_fabric_name());
1296 		cpu_relax();
1297 		spin_lock(&pr_tmpl->registration_lock);
1298 	}
1299 
1300 	pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1301 		" Node: %s%s\n", tfo->get_fabric_name(),
1302 		pr_reg->pr_reg_nacl->initiatorname,
1303 		(prf_isid) ? &i_buf[0] : "");
1304 	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1305 		" Port(s)\n", tfo->get_fabric_name(),
1306 		(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1307 		dev->transport->name);
1308 	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1309 		" 0x%08x\n", tfo->get_fabric_name(), pr_reg->pr_res_key,
1310 		pr_reg->pr_res_generation);
1311 
1312 	if (!preempt_and_abort_list) {
1313 		pr_reg->pr_reg_deve = NULL;
1314 		pr_reg->pr_reg_nacl = NULL;
1315 		kfree(pr_reg->pr_aptpl_buf);
1316 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1317 		return;
1318 	}
1319 	/*
1320 	 * For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1321 	 * are released once the ABORT_TASK_SET has completed..
1322 	 */
1323 	list_add_tail(&pr_reg->pr_reg_abort_list, preempt_and_abort_list);
1324 }
1325 
1326 void core_scsi3_free_pr_reg_from_nacl(
1327 	struct se_device *dev,
1328 	struct se_node_acl *nacl)
1329 {
1330 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1331 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1332 	/*
1333 	 * If the passed se_node_acl matches the reservation holder,
1334 	 * release the reservation.
1335 	 */
1336 	spin_lock(&dev->dev_reservation_lock);
1337 	pr_res_holder = dev->dev_pr_res_holder;
1338 	if ((pr_res_holder != NULL) &&
1339 	    (pr_res_holder->pr_reg_nacl == nacl))
1340 		__core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0);
1341 	spin_unlock(&dev->dev_reservation_lock);
1342 	/*
1343 	 * Release any registration associated with the struct se_node_acl.
1344 	 */
1345 	spin_lock(&pr_tmpl->registration_lock);
1346 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1347 			&pr_tmpl->registration_list, pr_reg_list) {
1348 
1349 		if (pr_reg->pr_reg_nacl != nacl)
1350 			continue;
1351 
1352 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1353 	}
1354 	spin_unlock(&pr_tmpl->registration_lock);
1355 }
1356 
1357 void core_scsi3_free_all_registrations(
1358 	struct se_device *dev)
1359 {
1360 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
1361 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1362 
1363 	spin_lock(&dev->dev_reservation_lock);
1364 	pr_res_holder = dev->dev_pr_res_holder;
1365 	if (pr_res_holder != NULL) {
1366 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1367 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
1368 				pr_res_holder, 0);
1369 	}
1370 	spin_unlock(&dev->dev_reservation_lock);
1371 
1372 	spin_lock(&pr_tmpl->registration_lock);
1373 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1374 			&pr_tmpl->registration_list, pr_reg_list) {
1375 
1376 		__core_scsi3_free_registration(dev, pr_reg, NULL, 0);
1377 	}
1378 	spin_unlock(&pr_tmpl->registration_lock);
1379 
1380 	spin_lock(&pr_tmpl->aptpl_reg_lock);
1381 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1382 				pr_reg_aptpl_list) {
1383 		list_del(&pr_reg->pr_reg_aptpl_list);
1384 		kfree(pr_reg->pr_aptpl_buf);
1385 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
1386 	}
1387 	spin_unlock(&pr_tmpl->aptpl_reg_lock);
1388 }
1389 
1390 static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1391 {
1392 	return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1393 			&tpg->tpg_group.cg_item);
1394 }
1395 
1396 static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1397 {
1398 	configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1399 			&tpg->tpg_group.cg_item);
1400 
1401 	atomic_dec(&tpg->tpg_pr_ref_count);
1402 	smp_mb__after_atomic_dec();
1403 }
1404 
1405 static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1406 {
1407 	struct se_portal_group *tpg = nacl->se_tpg;
1408 
1409 	if (nacl->dynamic_node_acl)
1410 		return 0;
1411 
1412 	return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1413 			&nacl->acl_group.cg_item);
1414 }
1415 
1416 static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1417 {
1418 	struct se_portal_group *tpg = nacl->se_tpg;
1419 
1420 	if (nacl->dynamic_node_acl) {
1421 		atomic_dec(&nacl->acl_pr_ref_count);
1422 		smp_mb__after_atomic_dec();
1423 		return;
1424 	}
1425 
1426 	configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1427 			&nacl->acl_group.cg_item);
1428 
1429 	atomic_dec(&nacl->acl_pr_ref_count);
1430 	smp_mb__after_atomic_dec();
1431 }
1432 
1433 static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1434 {
1435 	struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1436 	struct se_node_acl *nacl;
1437 	struct se_portal_group *tpg;
1438 	/*
1439 	 * For nacl->dynamic_node_acl=1
1440 	 */
1441 	if (!lun_acl)
1442 		return 0;
1443 
1444 	nacl = lun_acl->se_lun_nacl;
1445 	tpg = nacl->se_tpg;
1446 
1447 	return configfs_depend_item(tpg->se_tpg_tfo->tf_subsys,
1448 			&lun_acl->se_lun_group.cg_item);
1449 }
1450 
1451 static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1452 {
1453 	struct se_lun_acl *lun_acl = se_deve->se_lun_acl;
1454 	struct se_node_acl *nacl;
1455 	struct se_portal_group *tpg;
1456 	/*
1457 	 * For nacl->dynamic_node_acl=1
1458 	 */
1459 	if (!lun_acl) {
1460 		atomic_dec(&se_deve->pr_ref_count);
1461 		smp_mb__after_atomic_dec();
1462 		return;
1463 	}
1464 	nacl = lun_acl->se_lun_nacl;
1465 	tpg = nacl->se_tpg;
1466 
1467 	configfs_undepend_item(tpg->se_tpg_tfo->tf_subsys,
1468 			&lun_acl->se_lun_group.cg_item);
1469 
1470 	atomic_dec(&se_deve->pr_ref_count);
1471 	smp_mb__after_atomic_dec();
1472 }
1473 
1474 static int core_scsi3_decode_spec_i_port(
1475 	struct se_cmd *cmd,
1476 	struct se_portal_group *tpg,
1477 	unsigned char *l_isid,
1478 	u64 sa_res_key,
1479 	int all_tg_pt,
1480 	int aptpl)
1481 {
1482 	struct se_device *dev = cmd->se_dev;
1483 	struct se_port *tmp_port;
1484 	struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1485 	struct se_session *se_sess = cmd->se_sess;
1486 	struct se_node_acl *dest_node_acl = NULL;
1487 	struct se_dev_entry *dest_se_deve = NULL, *local_se_deve;
1488 	struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1489 	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1490 	struct list_head tid_dest_list;
1491 	struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1492 	struct target_core_fabric_ops *tmp_tf_ops;
1493 	unsigned char *buf;
1494 	unsigned char *ptr, *i_str = NULL, proto_ident, tmp_proto_ident;
1495 	char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
1496 	u32 tpdl, tid_len = 0;
1497 	int ret, dest_local_nexus, prf_isid;
1498 	u32 dest_rtpi = 0;
1499 
1500 	memset(dest_iport, 0, 64);
1501 	INIT_LIST_HEAD(&tid_dest_list);
1502 
1503 	local_se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
1504 	/*
1505 	 * Allocate a struct pr_transport_id_holder and setup the
1506 	 * local_node_acl and local_se_deve pointers and add to
1507 	 * struct list_head tid_dest_list for add registration
1508 	 * processing in the loop of tid_dest_list below.
1509 	 */
1510 	tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1511 	if (!tidh_new) {
1512 		pr_err("Unable to allocate tidh_new\n");
1513 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1514 		return -EINVAL;
1515 	}
1516 	INIT_LIST_HEAD(&tidh_new->dest_list);
1517 	tidh_new->dest_tpg = tpg;
1518 	tidh_new->dest_node_acl = se_sess->se_node_acl;
1519 	tidh_new->dest_se_deve = local_se_deve;
1520 
1521 	local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1522 				se_sess->se_node_acl, local_se_deve, l_isid,
1523 				sa_res_key, all_tg_pt, aptpl);
1524 	if (!local_pr_reg) {
1525 		kfree(tidh_new);
1526 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1527 		return -ENOMEM;
1528 	}
1529 	tidh_new->dest_pr_reg = local_pr_reg;
1530 	/*
1531 	 * The local I_T nexus does not hold any configfs dependances,
1532 	 * so we set tid_h->dest_local_nexus=1 to prevent the
1533 	 * configfs_undepend_item() calls in the tid_dest_list loops below.
1534 	 */
1535 	tidh_new->dest_local_nexus = 1;
1536 	list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1537 
1538 	buf = transport_kmap_data_sg(cmd);
1539 	/*
1540 	 * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1541 	 * first extract TransportID Parameter Data Length, and make sure
1542 	 * the value matches up to the SCSI expected data transfer length.
1543 	 */
1544 	tpdl = (buf[24] & 0xff) << 24;
1545 	tpdl |= (buf[25] & 0xff) << 16;
1546 	tpdl |= (buf[26] & 0xff) << 8;
1547 	tpdl |= buf[27] & 0xff;
1548 
1549 	if ((tpdl + 28) != cmd->data_length) {
1550 		pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1551 			" does not equal CDB data_length: %u\n", tpdl,
1552 			cmd->data_length);
1553 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1554 		ret = -EINVAL;
1555 		goto out;
1556 	}
1557 	/*
1558 	 * Start processing the received transport IDs using the
1559 	 * receiving I_T Nexus portal's fabric dependent methods to
1560 	 * obtain the SCSI Initiator Port/Device Identifiers.
1561 	 */
1562 	ptr = &buf[28];
1563 
1564 	while (tpdl > 0) {
1565 		proto_ident = (ptr[0] & 0x0f);
1566 		dest_tpg = NULL;
1567 
1568 		spin_lock(&dev->se_port_lock);
1569 		list_for_each_entry(tmp_port, &dev->dev_sep_list, sep_list) {
1570 			tmp_tpg = tmp_port->sep_tpg;
1571 			if (!tmp_tpg)
1572 				continue;
1573 			tmp_tf_ops = tmp_tpg->se_tpg_tfo;
1574 			if (!tmp_tf_ops)
1575 				continue;
1576 			if (!tmp_tf_ops->get_fabric_proto_ident ||
1577 			    !tmp_tf_ops->tpg_parse_pr_out_transport_id)
1578 				continue;
1579 			/*
1580 			 * Look for the matching proto_ident provided by
1581 			 * the received TransportID
1582 			 */
1583 			tmp_proto_ident = tmp_tf_ops->get_fabric_proto_ident(tmp_tpg);
1584 			if (tmp_proto_ident != proto_ident)
1585 				continue;
1586 			dest_rtpi = tmp_port->sep_rtpi;
1587 
1588 			i_str = tmp_tf_ops->tpg_parse_pr_out_transport_id(
1589 					tmp_tpg, (const char *)ptr, &tid_len,
1590 					&iport_ptr);
1591 			if (!i_str)
1592 				continue;
1593 
1594 			atomic_inc(&tmp_tpg->tpg_pr_ref_count);
1595 			smp_mb__after_atomic_inc();
1596 			spin_unlock(&dev->se_port_lock);
1597 
1598 			ret = core_scsi3_tpg_depend_item(tmp_tpg);
1599 			if (ret != 0) {
1600 				pr_err(" core_scsi3_tpg_depend_item()"
1601 					" for tmp_tpg\n");
1602 				atomic_dec(&tmp_tpg->tpg_pr_ref_count);
1603 				smp_mb__after_atomic_dec();
1604 				cmd->scsi_sense_reason =
1605 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1606 				ret = -EINVAL;
1607 				goto out;
1608 			}
1609 			/*
1610 			 * Locate the desination initiator ACL to be registered
1611 			 * from the decoded fabric module specific TransportID
1612 			 * at *i_str.
1613 			 */
1614 			spin_lock_irq(&tmp_tpg->acl_node_lock);
1615 			dest_node_acl = __core_tpg_get_initiator_node_acl(
1616 						tmp_tpg, i_str);
1617 			if (dest_node_acl) {
1618 				atomic_inc(&dest_node_acl->acl_pr_ref_count);
1619 				smp_mb__after_atomic_inc();
1620 			}
1621 			spin_unlock_irq(&tmp_tpg->acl_node_lock);
1622 
1623 			if (!dest_node_acl) {
1624 				core_scsi3_tpg_undepend_item(tmp_tpg);
1625 				spin_lock(&dev->se_port_lock);
1626 				continue;
1627 			}
1628 
1629 			ret = core_scsi3_nodeacl_depend_item(dest_node_acl);
1630 			if (ret != 0) {
1631 				pr_err("configfs_depend_item() failed"
1632 					" for dest_node_acl->acl_group\n");
1633 				atomic_dec(&dest_node_acl->acl_pr_ref_count);
1634 				smp_mb__after_atomic_dec();
1635 				core_scsi3_tpg_undepend_item(tmp_tpg);
1636 				cmd->scsi_sense_reason =
1637 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1638 				ret = -EINVAL;
1639 				goto out;
1640 			}
1641 
1642 			dest_tpg = tmp_tpg;
1643 			pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1644 				" %s Port RTPI: %hu\n",
1645 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1646 				dest_node_acl->initiatorname, dest_rtpi);
1647 
1648 			spin_lock(&dev->se_port_lock);
1649 			break;
1650 		}
1651 		spin_unlock(&dev->se_port_lock);
1652 
1653 		if (!dest_tpg) {
1654 			pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1655 					" dest_tpg\n");
1656 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1657 			ret = -EINVAL;
1658 			goto out;
1659 		}
1660 #if 0
1661 		pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1662 			" tid_len: %d for %s + %s\n",
1663 			dest_tpg->se_tpg_tfo->get_fabric_name(), cmd->data_length,
1664 			tpdl, tid_len, i_str, iport_ptr);
1665 #endif
1666 		if (tid_len > tpdl) {
1667 			pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1668 				" %u for Transport ID: %s\n", tid_len, ptr);
1669 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1670 			core_scsi3_tpg_undepend_item(dest_tpg);
1671 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1672 			ret = -EINVAL;
1673 			goto out;
1674 		}
1675 		/*
1676 		 * Locate the desintation struct se_dev_entry pointer for matching
1677 		 * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1678 		 * Target Port.
1679 		 */
1680 		dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1681 					dest_rtpi);
1682 		if (!dest_se_deve) {
1683 			pr_err("Unable to locate %s dest_se_deve"
1684 				" from destination RTPI: %hu\n",
1685 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1686 				dest_rtpi);
1687 
1688 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1689 			core_scsi3_tpg_undepend_item(dest_tpg);
1690 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1691 			ret = -EINVAL;
1692 			goto out;
1693 		}
1694 
1695 		ret = core_scsi3_lunacl_depend_item(dest_se_deve);
1696 		if (ret < 0) {
1697 			pr_err("core_scsi3_lunacl_depend_item()"
1698 					" failed\n");
1699 			atomic_dec(&dest_se_deve->pr_ref_count);
1700 			smp_mb__after_atomic_dec();
1701 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1702 			core_scsi3_tpg_undepend_item(dest_tpg);
1703 			cmd->scsi_sense_reason =
1704 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1705 			ret = -EINVAL;
1706 			goto out;
1707 		}
1708 #if 0
1709 		pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1710 			" dest_se_deve mapped_lun: %u\n",
1711 			dest_tpg->se_tpg_tfo->get_fabric_name(),
1712 			dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1713 #endif
1714 		/*
1715 		 * Skip any TransportIDs that already have a registration for
1716 		 * this target port.
1717 		 */
1718 		pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1719 					iport_ptr);
1720 		if (pr_reg_e) {
1721 			core_scsi3_put_pr_reg(pr_reg_e);
1722 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1723 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1724 			core_scsi3_tpg_undepend_item(dest_tpg);
1725 			ptr += tid_len;
1726 			tpdl -= tid_len;
1727 			tid_len = 0;
1728 			continue;
1729 		}
1730 		/*
1731 		 * Allocate a struct pr_transport_id_holder and setup
1732 		 * the dest_node_acl and dest_se_deve pointers for the
1733 		 * loop below.
1734 		 */
1735 		tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1736 				GFP_KERNEL);
1737 		if (!tidh_new) {
1738 			pr_err("Unable to allocate tidh_new\n");
1739 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1740 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1741 			core_scsi3_tpg_undepend_item(dest_tpg);
1742 			cmd->scsi_sense_reason =
1743 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1744 			ret = -ENOMEM;
1745 			goto out;
1746 		}
1747 		INIT_LIST_HEAD(&tidh_new->dest_list);
1748 		tidh_new->dest_tpg = dest_tpg;
1749 		tidh_new->dest_node_acl = dest_node_acl;
1750 		tidh_new->dest_se_deve = dest_se_deve;
1751 
1752 		/*
1753 		 * Allocate, but do NOT add the registration for the
1754 		 * TransportID referenced SCSI Initiator port.  This
1755 		 * done because of the following from spc4r17 in section
1756 		 * 6.14.3 wrt SPEC_I_PT:
1757 		 *
1758 		 * "If a registration fails for any initiator port (e.g., if th
1759 		 * logical unit does not have enough resources available to
1760 		 * hold the registration information), no registrations shall be
1761 		 * made, and the command shall be terminated with
1762 		 * CHECK CONDITION status."
1763 		 *
1764 		 * That means we call __core_scsi3_alloc_registration() here,
1765 		 * and then call __core_scsi3_add_registration() in the
1766 		 * 2nd loop which will never fail.
1767 		 */
1768 		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1769 				dest_node_acl, dest_se_deve, iport_ptr,
1770 				sa_res_key, all_tg_pt, aptpl);
1771 		if (!dest_pr_reg) {
1772 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1773 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1774 			core_scsi3_tpg_undepend_item(dest_tpg);
1775 			kfree(tidh_new);
1776 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1777 			ret = -EINVAL;
1778 			goto out;
1779 		}
1780 		tidh_new->dest_pr_reg = dest_pr_reg;
1781 		list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1782 
1783 		ptr += tid_len;
1784 		tpdl -= tid_len;
1785 		tid_len = 0;
1786 
1787 	}
1788 
1789 	transport_kunmap_data_sg(cmd);
1790 
1791 	/*
1792 	 * Go ahead and create a registrations from tid_dest_list for the
1793 	 * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1794 	 * and dest_se_deve.
1795 	 *
1796 	 * The SA Reservation Key from the PROUT is set for the
1797 	 * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1798 	 * means that the TransportID Initiator port will be
1799 	 * registered on all of the target ports in the SCSI target device
1800 	 * ALL_TG_PT=0 means the registration will only be for the
1801 	 * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1802 	 * was received.
1803 	 */
1804 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1805 		dest_tpg = tidh->dest_tpg;
1806 		dest_node_acl = tidh->dest_node_acl;
1807 		dest_se_deve = tidh->dest_se_deve;
1808 		dest_pr_reg = tidh->dest_pr_reg;
1809 		dest_local_nexus = tidh->dest_local_nexus;
1810 
1811 		list_del(&tidh->dest_list);
1812 		kfree(tidh);
1813 
1814 		memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1815 		prf_isid = core_pr_dump_initiator_port(dest_pr_reg, &i_buf[0],
1816 						PR_REG_ISID_ID_LEN);
1817 
1818 		__core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1819 					dest_pr_reg, 0, 0);
1820 
1821 		pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1822 			" registered Transport ID for Node: %s%s Mapped LUN:"
1823 			" %u\n", dest_tpg->se_tpg_tfo->get_fabric_name(),
1824 			dest_node_acl->initiatorname, (prf_isid) ?
1825 			&i_buf[0] : "", dest_se_deve->mapped_lun);
1826 
1827 		if (dest_local_nexus)
1828 			continue;
1829 
1830 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1831 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1832 		core_scsi3_tpg_undepend_item(dest_tpg);
1833 	}
1834 
1835 	return 0;
1836 out:
1837 	transport_kunmap_data_sg(cmd);
1838 	/*
1839 	 * For the failure case, release everything from tid_dest_list
1840 	 * including *dest_pr_reg and the configfs dependances..
1841 	 */
1842 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1843 		dest_tpg = tidh->dest_tpg;
1844 		dest_node_acl = tidh->dest_node_acl;
1845 		dest_se_deve = tidh->dest_se_deve;
1846 		dest_pr_reg = tidh->dest_pr_reg;
1847 		dest_local_nexus = tidh->dest_local_nexus;
1848 
1849 		list_del(&tidh->dest_list);
1850 		kfree(tidh);
1851 		/*
1852 		 * Release any extra ALL_TG_PT=1 registrations for
1853 		 * the SPEC_I_PT=1 case.
1854 		 */
1855 		list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1856 				&dest_pr_reg->pr_reg_atp_list,
1857 				pr_reg_atp_mem_list) {
1858 			list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1859 			core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1860 			kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1861 		}
1862 
1863 		kfree(dest_pr_reg->pr_aptpl_buf);
1864 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1865 
1866 		if (dest_local_nexus)
1867 			continue;
1868 
1869 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1870 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1871 		core_scsi3_tpg_undepend_item(dest_tpg);
1872 	}
1873 	return ret;
1874 }
1875 
1876 /*
1877  * Called with struct se_device->dev_reservation_lock held
1878  */
1879 static int __core_scsi3_update_aptpl_buf(
1880 	struct se_device *dev,
1881 	unsigned char *buf,
1882 	u32 pr_aptpl_buf_len,
1883 	int clear_aptpl_metadata)
1884 {
1885 	struct se_lun *lun;
1886 	struct se_portal_group *tpg;
1887 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1888 	struct t10_pr_registration *pr_reg;
1889 	unsigned char tmp[512], isid_buf[32];
1890 	ssize_t len = 0;
1891 	int reg_count = 0;
1892 
1893 	memset(buf, 0, pr_aptpl_buf_len);
1894 	/*
1895 	 * Called to clear metadata once APTPL has been deactivated.
1896 	 */
1897 	if (clear_aptpl_metadata) {
1898 		snprintf(buf, pr_aptpl_buf_len,
1899 				"No Registrations or Reservations\n");
1900 		return 0;
1901 	}
1902 	/*
1903 	 * Walk the registration list..
1904 	 */
1905 	spin_lock(&su_dev->t10_pr.registration_lock);
1906 	list_for_each_entry(pr_reg, &su_dev->t10_pr.registration_list,
1907 			pr_reg_list) {
1908 
1909 		tmp[0] = '\0';
1910 		isid_buf[0] = '\0';
1911 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1912 		lun = pr_reg->pr_reg_tg_pt_lun;
1913 		/*
1914 		 * Write out any ISID value to APTPL metadata that was included
1915 		 * in the original registration.
1916 		 */
1917 		if (pr_reg->isid_present_at_reg)
1918 			snprintf(isid_buf, 32, "initiator_sid=%s\n",
1919 					pr_reg->pr_reg_isid);
1920 		/*
1921 		 * Include special metadata if the pr_reg matches the
1922 		 * reservation holder.
1923 		 */
1924 		if (dev->dev_pr_res_holder == pr_reg) {
1925 			snprintf(tmp, 512, "PR_REG_START: %d"
1926 				"\ninitiator_fabric=%s\n"
1927 				"initiator_node=%s\n%s"
1928 				"sa_res_key=%llu\n"
1929 				"res_holder=1\nres_type=%02x\n"
1930 				"res_scope=%02x\nres_all_tg_pt=%d\n"
1931 				"mapped_lun=%u\n", reg_count,
1932 				tpg->se_tpg_tfo->get_fabric_name(),
1933 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1934 				pr_reg->pr_res_key, pr_reg->pr_res_type,
1935 				pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1936 				pr_reg->pr_res_mapped_lun);
1937 		} else {
1938 			snprintf(tmp, 512, "PR_REG_START: %d\n"
1939 				"initiator_fabric=%s\ninitiator_node=%s\n%s"
1940 				"sa_res_key=%llu\nres_holder=0\n"
1941 				"res_all_tg_pt=%d\nmapped_lun=%u\n",
1942 				reg_count, tpg->se_tpg_tfo->get_fabric_name(),
1943 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1944 				pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1945 				pr_reg->pr_res_mapped_lun);
1946 		}
1947 
1948 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1949 			pr_err("Unable to update renaming"
1950 				" APTPL metadata\n");
1951 			spin_unlock(&su_dev->t10_pr.registration_lock);
1952 			return -EMSGSIZE;
1953 		}
1954 		len += sprintf(buf+len, "%s", tmp);
1955 
1956 		/*
1957 		 * Include information about the associated SCSI target port.
1958 		 */
1959 		snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1960 			"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%u\nPR_REG_END:"
1961 			" %d\n", tpg->se_tpg_tfo->get_fabric_name(),
1962 			tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1963 			tpg->se_tpg_tfo->tpg_get_tag(tpg),
1964 			lun->lun_sep->sep_rtpi, lun->unpacked_lun, reg_count);
1965 
1966 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1967 			pr_err("Unable to update renaming"
1968 				" APTPL metadata\n");
1969 			spin_unlock(&su_dev->t10_pr.registration_lock);
1970 			return -EMSGSIZE;
1971 		}
1972 		len += sprintf(buf+len, "%s", tmp);
1973 		reg_count++;
1974 	}
1975 	spin_unlock(&su_dev->t10_pr.registration_lock);
1976 
1977 	if (!reg_count)
1978 		len += sprintf(buf+len, "No Registrations or Reservations");
1979 
1980 	return 0;
1981 }
1982 
1983 static int core_scsi3_update_aptpl_buf(
1984 	struct se_device *dev,
1985 	unsigned char *buf,
1986 	u32 pr_aptpl_buf_len,
1987 	int clear_aptpl_metadata)
1988 {
1989 	int ret;
1990 
1991 	spin_lock(&dev->dev_reservation_lock);
1992 	ret = __core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len,
1993 				clear_aptpl_metadata);
1994 	spin_unlock(&dev->dev_reservation_lock);
1995 
1996 	return ret;
1997 }
1998 
1999 /*
2000  * Called with struct se_device->aptpl_file_mutex held
2001  */
2002 static int __core_scsi3_write_aptpl_to_file(
2003 	struct se_device *dev,
2004 	unsigned char *buf,
2005 	u32 pr_aptpl_buf_len)
2006 {
2007 	struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
2008 	struct file *file;
2009 	struct iovec iov[1];
2010 	mm_segment_t old_fs;
2011 	int flags = O_RDWR | O_CREAT | O_TRUNC;
2012 	char path[512];
2013 	int ret;
2014 
2015 	memset(iov, 0, sizeof(struct iovec));
2016 	memset(path, 0, 512);
2017 
2018 	if (strlen(&wwn->unit_serial[0]) >= 512) {
2019 		pr_err("WWN value for struct se_device does not fit"
2020 			" into path buffer\n");
2021 		return -EMSGSIZE;
2022 	}
2023 
2024 	snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
2025 	file = filp_open(path, flags, 0600);
2026 	if (IS_ERR(file) || !file || !file->f_dentry) {
2027 		pr_err("filp_open(%s) for APTPL metadata"
2028 			" failed\n", path);
2029 		return (PTR_ERR(file) < 0 ? PTR_ERR(file) : -ENOENT);
2030 	}
2031 
2032 	iov[0].iov_base = &buf[0];
2033 	if (!pr_aptpl_buf_len)
2034 		iov[0].iov_len = (strlen(&buf[0]) + 1); /* Add extra for NULL */
2035 	else
2036 		iov[0].iov_len = pr_aptpl_buf_len;
2037 
2038 	old_fs = get_fs();
2039 	set_fs(get_ds());
2040 	ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
2041 	set_fs(old_fs);
2042 
2043 	if (ret < 0) {
2044 		pr_debug("Error writing APTPL metadata file: %s\n", path);
2045 		filp_close(file, NULL);
2046 		return -EIO;
2047 	}
2048 	filp_close(file, NULL);
2049 
2050 	return 0;
2051 }
2052 
2053 static int core_scsi3_update_and_write_aptpl(
2054 	struct se_device *dev,
2055 	unsigned char *in_buf,
2056 	u32 in_pr_aptpl_buf_len)
2057 {
2058 	unsigned char null_buf[64], *buf;
2059 	u32 pr_aptpl_buf_len;
2060 	int ret, clear_aptpl_metadata = 0;
2061 	/*
2062 	 * Can be called with a NULL pointer from PROUT service action CLEAR
2063 	 */
2064 	if (!in_buf) {
2065 		memset(null_buf, 0, 64);
2066 		buf = &null_buf[0];
2067 		/*
2068 		 * This will clear the APTPL metadata to:
2069 		 * "No Registrations or Reservations" status
2070 		 */
2071 		pr_aptpl_buf_len = 64;
2072 		clear_aptpl_metadata = 1;
2073 	} else {
2074 		buf = in_buf;
2075 		pr_aptpl_buf_len = in_pr_aptpl_buf_len;
2076 	}
2077 
2078 	ret = core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len,
2079 				clear_aptpl_metadata);
2080 	if (ret != 0)
2081 		return ret;
2082 	/*
2083 	 * __core_scsi3_write_aptpl_to_file() will call strlen()
2084 	 * on the passed buf to determine pr_aptpl_buf_len.
2085 	 */
2086 	ret = __core_scsi3_write_aptpl_to_file(dev, buf, 0);
2087 	if (ret != 0)
2088 		return ret;
2089 
2090 	return ret;
2091 }
2092 
2093 static int core_scsi3_emulate_pro_register(
2094 	struct se_cmd *cmd,
2095 	u64 res_key,
2096 	u64 sa_res_key,
2097 	int aptpl,
2098 	int all_tg_pt,
2099 	int spec_i_pt,
2100 	int ignore_key)
2101 {
2102 	struct se_session *se_sess = cmd->se_sess;
2103 	struct se_device *dev = cmd->se_dev;
2104 	struct se_dev_entry *se_deve;
2105 	struct se_lun *se_lun = cmd->se_lun;
2106 	struct se_portal_group *se_tpg;
2107 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp, *pr_reg_e;
2108 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2109 	/* Used for APTPL metadata w/ UNREGISTER */
2110 	unsigned char *pr_aptpl_buf = NULL;
2111 	unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2112 	int pr_holder = 0, ret = 0, type;
2113 
2114 	if (!se_sess || !se_lun) {
2115 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2116 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2117 		return -EINVAL;
2118 	}
2119 	se_tpg = se_sess->se_tpg;
2120 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2121 
2122 	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2123 		memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2124 		se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2125 				PR_REG_ISID_LEN);
2126 		isid_ptr = &isid_buf[0];
2127 	}
2128 	/*
2129 	 * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2130 	 */
2131 	pr_reg_e = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2132 	if (!pr_reg_e) {
2133 		if (res_key) {
2134 			pr_warn("SPC-3 PR: Reservation Key non-zero"
2135 				" for SA REGISTER, returning CONFLICT\n");
2136 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2137 			return -EINVAL;
2138 		}
2139 		/*
2140 		 * Do nothing but return GOOD status.
2141 		 */
2142 		if (!sa_res_key)
2143 			return 0;
2144 
2145 		if (!spec_i_pt) {
2146 			/*
2147 			 * Perform the Service Action REGISTER on the Initiator
2148 			 * Port Endpoint that the PRO was received from on the
2149 			 * Logical Unit of the SCSI device server.
2150 			 */
2151 			ret = core_scsi3_alloc_registration(cmd->se_dev,
2152 					se_sess->se_node_acl, se_deve, isid_ptr,
2153 					sa_res_key, all_tg_pt, aptpl,
2154 					ignore_key, 0);
2155 			if (ret != 0) {
2156 				pr_err("Unable to allocate"
2157 					" struct t10_pr_registration\n");
2158 				cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
2159 				return -EINVAL;
2160 			}
2161 		} else {
2162 			/*
2163 			 * Register both the Initiator port that received
2164 			 * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2165 			 * TransportID from Parameter list and loop through
2166 			 * fabric dependent parameter list while calling
2167 			 * logic from of core_scsi3_alloc_registration() for
2168 			 * each TransportID provided SCSI Initiator Port/Device
2169 			 */
2170 			ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2171 					isid_ptr, sa_res_key, all_tg_pt, aptpl);
2172 			if (ret != 0)
2173 				return ret;
2174 		}
2175 		/*
2176 		 * Nothing left to do for the APTPL=0 case.
2177 		 */
2178 		if (!aptpl) {
2179 			pr_tmpl->pr_aptpl_active = 0;
2180 			core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
2181 			pr_debug("SPC-3 PR: Set APTPL Bit Deactivated for"
2182 					" REGISTER\n");
2183 			return 0;
2184 		}
2185 		/*
2186 		 * Locate the newly allocated local I_T Nexus *pr_reg, and
2187 		 * update the APTPL metadata information using its
2188 		 * preallocated *pr_reg->pr_aptpl_buf.
2189 		 */
2190 		pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev,
2191 				se_sess->se_node_acl, se_sess);
2192 
2193 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2194 				&pr_reg->pr_aptpl_buf[0],
2195 				pr_tmpl->pr_aptpl_buf_len);
2196 		if (!ret) {
2197 			pr_tmpl->pr_aptpl_active = 1;
2198 			pr_debug("SPC-3 PR: Set APTPL Bit Activated for REGISTER\n");
2199 		}
2200 
2201 		core_scsi3_put_pr_reg(pr_reg);
2202 		return ret;
2203 	} else {
2204 		/*
2205 		 * Locate the existing *pr_reg via struct se_node_acl pointers
2206 		 */
2207 		pr_reg = pr_reg_e;
2208 		type = pr_reg->pr_res_type;
2209 
2210 		if (!ignore_key) {
2211 			if (res_key != pr_reg->pr_res_key) {
2212 				pr_err("SPC-3 PR REGISTER: Received"
2213 					" res_key: 0x%016Lx does not match"
2214 					" existing SA REGISTER res_key:"
2215 					" 0x%016Lx\n", res_key,
2216 					pr_reg->pr_res_key);
2217 				core_scsi3_put_pr_reg(pr_reg);
2218 				cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2219 				return -EINVAL;
2220 			}
2221 		}
2222 		if (spec_i_pt) {
2223 			pr_err("SPC-3 PR UNREGISTER: SPEC_I_PT"
2224 				" set while sa_res_key=0\n");
2225 			core_scsi3_put_pr_reg(pr_reg);
2226 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
2227 			return -EINVAL;
2228 		}
2229 		/*
2230 		 * An existing ALL_TG_PT=1 registration being released
2231 		 * must also set ALL_TG_PT=1 in the incoming PROUT.
2232 		 */
2233 		if (pr_reg->pr_reg_all_tg_pt && !(all_tg_pt)) {
2234 			pr_err("SPC-3 PR UNREGISTER: ALL_TG_PT=1"
2235 				" registration exists, but ALL_TG_PT=1 bit not"
2236 				" present in received PROUT\n");
2237 			core_scsi3_put_pr_reg(pr_reg);
2238 			cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
2239 			return -EINVAL;
2240 		}
2241 		/*
2242 		 * Allocate APTPL metadata buffer used for UNREGISTER ops
2243 		 */
2244 		if (aptpl) {
2245 			pr_aptpl_buf = kzalloc(pr_tmpl->pr_aptpl_buf_len,
2246 						GFP_KERNEL);
2247 			if (!pr_aptpl_buf) {
2248 				pr_err("Unable to allocate"
2249 					" pr_aptpl_buf\n");
2250 				core_scsi3_put_pr_reg(pr_reg);
2251 				cmd->scsi_sense_reason =
2252 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2253 				return -EINVAL;
2254 			}
2255 		}
2256 		/*
2257 		 * sa_res_key=0 Unregister Reservation Key for registered I_T
2258 		 * Nexus sa_res_key=1 Change Reservation Key for registered I_T
2259 		 * Nexus.
2260 		 */
2261 		if (!sa_res_key) {
2262 			pr_holder = core_scsi3_check_implict_release(
2263 					cmd->se_dev, pr_reg);
2264 			if (pr_holder < 0) {
2265 				kfree(pr_aptpl_buf);
2266 				core_scsi3_put_pr_reg(pr_reg);
2267 				cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2268 				return -EINVAL;
2269 			}
2270 
2271 			spin_lock(&pr_tmpl->registration_lock);
2272 			/*
2273 			 * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2274 			 * and matching pr_res_key.
2275 			 */
2276 			if (pr_reg->pr_reg_all_tg_pt) {
2277 				list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2278 						&pr_tmpl->registration_list,
2279 						pr_reg_list) {
2280 
2281 					if (!pr_reg_p->pr_reg_all_tg_pt)
2282 						continue;
2283 
2284 					if (pr_reg_p->pr_res_key != res_key)
2285 						continue;
2286 
2287 					if (pr_reg == pr_reg_p)
2288 						continue;
2289 
2290 					if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2291 						   pr_reg_p->pr_reg_nacl->initiatorname))
2292 						continue;
2293 
2294 					__core_scsi3_free_registration(dev,
2295 							pr_reg_p, NULL, 0);
2296 				}
2297 			}
2298 			/*
2299 			 * Release the calling I_T Nexus registration now..
2300 			 */
2301 			__core_scsi3_free_registration(cmd->se_dev, pr_reg,
2302 							NULL, 1);
2303 			/*
2304 			 * From spc4r17, section 5.7.11.3 Unregistering
2305 			 *
2306 			 * If the persistent reservation is a registrants only
2307 			 * type, the device server shall establish a unit
2308 			 * attention condition for the initiator port associated
2309 			 * with every registered I_T nexus except for the I_T
2310 			 * nexus on which the PERSISTENT RESERVE OUT command was
2311 			 * received, with the additional sense code set to
2312 			 * RESERVATIONS RELEASED.
2313 			 */
2314 			if (pr_holder &&
2315 			   ((type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
2316 			    (type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY))) {
2317 				list_for_each_entry(pr_reg_p,
2318 						&pr_tmpl->registration_list,
2319 						pr_reg_list) {
2320 
2321 					core_scsi3_ua_allocate(
2322 						pr_reg_p->pr_reg_nacl,
2323 						pr_reg_p->pr_res_mapped_lun,
2324 						0x2A,
2325 						ASCQ_2AH_RESERVATIONS_RELEASED);
2326 				}
2327 			}
2328 			spin_unlock(&pr_tmpl->registration_lock);
2329 
2330 			if (!aptpl) {
2331 				pr_tmpl->pr_aptpl_active = 0;
2332 				core_scsi3_update_and_write_aptpl(dev, NULL, 0);
2333 				pr_debug("SPC-3 PR: Set APTPL Bit Deactivated"
2334 						" for UNREGISTER\n");
2335 				return 0;
2336 			}
2337 
2338 			ret = core_scsi3_update_and_write_aptpl(dev,
2339 					&pr_aptpl_buf[0],
2340 					pr_tmpl->pr_aptpl_buf_len);
2341 			if (!ret) {
2342 				pr_tmpl->pr_aptpl_active = 1;
2343 				pr_debug("SPC-3 PR: Set APTPL Bit Activated"
2344 						" for UNREGISTER\n");
2345 			}
2346 
2347 			kfree(pr_aptpl_buf);
2348 			return ret;
2349 		} else {
2350 			/*
2351 			 * Increment PRgeneration counter for struct se_device"
2352 			 * upon a successful REGISTER, see spc4r17 section 6.3.2
2353 			 * READ_KEYS service action.
2354 			 */
2355 			pr_reg->pr_res_generation = core_scsi3_pr_generation(
2356 							cmd->se_dev);
2357 			pr_reg->pr_res_key = sa_res_key;
2358 			pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2359 				" Key for %s to: 0x%016Lx PRgeneration:"
2360 				" 0x%08x\n", cmd->se_tfo->get_fabric_name(),
2361 				(ignore_key) ? "_AND_IGNORE_EXISTING_KEY" : "",
2362 				pr_reg->pr_reg_nacl->initiatorname,
2363 				pr_reg->pr_res_key, pr_reg->pr_res_generation);
2364 
2365 			if (!aptpl) {
2366 				pr_tmpl->pr_aptpl_active = 0;
2367 				core_scsi3_update_and_write_aptpl(dev, NULL, 0);
2368 				core_scsi3_put_pr_reg(pr_reg);
2369 				pr_debug("SPC-3 PR: Set APTPL Bit Deactivated"
2370 						" for REGISTER\n");
2371 				return 0;
2372 			}
2373 
2374 			ret = core_scsi3_update_and_write_aptpl(dev,
2375 					&pr_aptpl_buf[0],
2376 					pr_tmpl->pr_aptpl_buf_len);
2377 			if (!ret) {
2378 				pr_tmpl->pr_aptpl_active = 1;
2379 				pr_debug("SPC-3 PR: Set APTPL Bit Activated"
2380 						" for REGISTER\n");
2381 			}
2382 
2383 			kfree(pr_aptpl_buf);
2384 			core_scsi3_put_pr_reg(pr_reg);
2385 		}
2386 	}
2387 	return 0;
2388 }
2389 
2390 unsigned char *core_scsi3_pr_dump_type(int type)
2391 {
2392 	switch (type) {
2393 	case PR_TYPE_WRITE_EXCLUSIVE:
2394 		return "Write Exclusive Access";
2395 	case PR_TYPE_EXCLUSIVE_ACCESS:
2396 		return "Exclusive Access";
2397 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2398 		return "Write Exclusive Access, Registrants Only";
2399 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2400 		return "Exclusive Access, Registrants Only";
2401 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2402 		return "Write Exclusive Access, All Registrants";
2403 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2404 		return "Exclusive Access, All Registrants";
2405 	default:
2406 		break;
2407 	}
2408 
2409 	return "Unknown SPC-3 PR Type";
2410 }
2411 
2412 static int core_scsi3_pro_reserve(
2413 	struct se_cmd *cmd,
2414 	struct se_device *dev,
2415 	int type,
2416 	int scope,
2417 	u64 res_key)
2418 {
2419 	struct se_session *se_sess = cmd->se_sess;
2420 	struct se_dev_entry *se_deve;
2421 	struct se_lun *se_lun = cmd->se_lun;
2422 	struct se_portal_group *se_tpg;
2423 	struct t10_pr_registration *pr_reg, *pr_res_holder;
2424 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2425 	char i_buf[PR_REG_ISID_ID_LEN];
2426 	int ret, prf_isid;
2427 
2428 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2429 
2430 	if (!se_sess || !se_lun) {
2431 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2432 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2433 		return -EINVAL;
2434 	}
2435 	se_tpg = se_sess->se_tpg;
2436 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2437 	/*
2438 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2439 	 */
2440 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2441 				se_sess);
2442 	if (!pr_reg) {
2443 		pr_err("SPC-3 PR: Unable to locate"
2444 			" PR_REGISTERED *pr_reg for RESERVE\n");
2445 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2446 		return -EINVAL;
2447 	}
2448 	/*
2449 	 * From spc4r17 Section 5.7.9: Reserving:
2450 	 *
2451 	 * An application client creates a persistent reservation by issuing
2452 	 * a PERSISTENT RESERVE OUT command with RESERVE service action through
2453 	 * a registered I_T nexus with the following parameters:
2454 	 *    a) RESERVATION KEY set to the value of the reservation key that is
2455 	 * 	 registered with the logical unit for the I_T nexus; and
2456 	 */
2457 	if (res_key != pr_reg->pr_res_key) {
2458 		pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2459 			" does not match existing SA REGISTER res_key:"
2460 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2461 		core_scsi3_put_pr_reg(pr_reg);
2462 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2463 		return -EINVAL;
2464 	}
2465 	/*
2466 	 * From spc4r17 Section 5.7.9: Reserving:
2467 	 *
2468 	 * From above:
2469 	 *  b) TYPE field and SCOPE field set to the persistent reservation
2470 	 *     being created.
2471 	 *
2472 	 * Only one persistent reservation is allowed at a time per logical unit
2473 	 * and that persistent reservation has a scope of LU_SCOPE.
2474 	 */
2475 	if (scope != PR_SCOPE_LU_SCOPE) {
2476 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2477 		core_scsi3_put_pr_reg(pr_reg);
2478 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
2479 		return -EINVAL;
2480 	}
2481 	/*
2482 	 * See if we have an existing PR reservation holder pointer at
2483 	 * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2484 	 * *pr_res_holder.
2485 	 */
2486 	spin_lock(&dev->dev_reservation_lock);
2487 	pr_res_holder = dev->dev_pr_res_holder;
2488 	if ((pr_res_holder)) {
2489 		/*
2490 		 * From spc4r17 Section 5.7.9: Reserving:
2491 		 *
2492 		 * If the device server receives a PERSISTENT RESERVE OUT
2493 		 * command from an I_T nexus other than a persistent reservation
2494 		 * holder (see 5.7.10) that attempts to create a persistent
2495 		 * reservation when a persistent reservation already exists for
2496 		 * the logical unit, then the command shall be completed with
2497 		 * RESERVATION CONFLICT status.
2498 		 */
2499 		if (pr_res_holder != pr_reg) {
2500 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2501 			pr_err("SPC-3 PR: Attempted RESERVE from"
2502 				" [%s]: %s while reservation already held by"
2503 				" [%s]: %s, returning RESERVATION_CONFLICT\n",
2504 				cmd->se_tfo->get_fabric_name(),
2505 				se_sess->se_node_acl->initiatorname,
2506 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2507 				pr_res_holder->pr_reg_nacl->initiatorname);
2508 
2509 			spin_unlock(&dev->dev_reservation_lock);
2510 			core_scsi3_put_pr_reg(pr_reg);
2511 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2512 			return -EINVAL;
2513 		}
2514 		/*
2515 		 * From spc4r17 Section 5.7.9: Reserving:
2516 		 *
2517 		 * If a persistent reservation holder attempts to modify the
2518 		 * type or scope of an existing persistent reservation, the
2519 		 * command shall be completed with RESERVATION CONFLICT status.
2520 		 */
2521 		if ((pr_res_holder->pr_res_type != type) ||
2522 		    (pr_res_holder->pr_res_scope != scope)) {
2523 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2524 			pr_err("SPC-3 PR: Attempted RESERVE from"
2525 				" [%s]: %s trying to change TYPE and/or SCOPE,"
2526 				" while reservation already held by [%s]: %s,"
2527 				" returning RESERVATION_CONFLICT\n",
2528 				cmd->se_tfo->get_fabric_name(),
2529 				se_sess->se_node_acl->initiatorname,
2530 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2531 				pr_res_holder->pr_reg_nacl->initiatorname);
2532 
2533 			spin_unlock(&dev->dev_reservation_lock);
2534 			core_scsi3_put_pr_reg(pr_reg);
2535 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2536 			return -EINVAL;
2537 		}
2538 		/*
2539 		 * From spc4r17 Section 5.7.9: Reserving:
2540 		 *
2541 		 * If the device server receives a PERSISTENT RESERVE OUT
2542 		 * command with RESERVE service action where the TYPE field and
2543 		 * the SCOPE field contain the same values as the existing type
2544 		 * and scope from a persistent reservation holder, it shall not
2545 		 * make any change to the existing persistent reservation and
2546 		 * shall completethe command with GOOD status.
2547 		 */
2548 		spin_unlock(&dev->dev_reservation_lock);
2549 		core_scsi3_put_pr_reg(pr_reg);
2550 		return 0;
2551 	}
2552 	/*
2553 	 * Otherwise, our *pr_reg becomes the PR reservation holder for said
2554 	 * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2555 	 */
2556 	pr_reg->pr_res_scope = scope;
2557 	pr_reg->pr_res_type = type;
2558 	pr_reg->pr_res_holder = 1;
2559 	dev->dev_pr_res_holder = pr_reg;
2560 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2561 				PR_REG_ISID_ID_LEN);
2562 
2563 	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2564 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2565 		cmd->se_tfo->get_fabric_name(), core_scsi3_pr_dump_type(type),
2566 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2567 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2568 			cmd->se_tfo->get_fabric_name(),
2569 			se_sess->se_node_acl->initiatorname,
2570 			(prf_isid) ? &i_buf[0] : "");
2571 	spin_unlock(&dev->dev_reservation_lock);
2572 
2573 	if (pr_tmpl->pr_aptpl_active) {
2574 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2575 				&pr_reg->pr_aptpl_buf[0],
2576 				pr_tmpl->pr_aptpl_buf_len);
2577 		if (!ret)
2578 			pr_debug("SPC-3 PR: Updated APTPL metadata"
2579 					" for RESERVE\n");
2580 	}
2581 
2582 	core_scsi3_put_pr_reg(pr_reg);
2583 	return 0;
2584 }
2585 
2586 static int core_scsi3_emulate_pro_reserve(
2587 	struct se_cmd *cmd,
2588 	int type,
2589 	int scope,
2590 	u64 res_key)
2591 {
2592 	struct se_device *dev = cmd->se_dev;
2593 	int ret = 0;
2594 
2595 	switch (type) {
2596 	case PR_TYPE_WRITE_EXCLUSIVE:
2597 	case PR_TYPE_EXCLUSIVE_ACCESS:
2598 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2599 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2600 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2601 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2602 		ret = core_scsi3_pro_reserve(cmd, dev, type, scope, res_key);
2603 		break;
2604 	default:
2605 		pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2606 			" 0x%02x\n", type);
2607 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
2608 		return -EINVAL;
2609 	}
2610 
2611 	return ret;
2612 }
2613 
2614 /*
2615  * Called with struct se_device->dev_reservation_lock held.
2616  */
2617 static void __core_scsi3_complete_pro_release(
2618 	struct se_device *dev,
2619 	struct se_node_acl *se_nacl,
2620 	struct t10_pr_registration *pr_reg,
2621 	int explict)
2622 {
2623 	struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2624 	char i_buf[PR_REG_ISID_ID_LEN];
2625 	int prf_isid;
2626 
2627 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2628 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2629 				PR_REG_ISID_ID_LEN);
2630 	/*
2631 	 * Go ahead and release the current PR reservation holder.
2632 	 */
2633 	dev->dev_pr_res_holder = NULL;
2634 
2635 	pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2636 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2637 		tfo->get_fabric_name(), (explict) ? "explict" : "implict",
2638 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
2639 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2640 	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2641 		tfo->get_fabric_name(), se_nacl->initiatorname,
2642 		(prf_isid) ? &i_buf[0] : "");
2643 	/*
2644 	 * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2645 	 */
2646 	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2647 }
2648 
2649 static int core_scsi3_emulate_pro_release(
2650 	struct se_cmd *cmd,
2651 	int type,
2652 	int scope,
2653 	u64 res_key)
2654 {
2655 	struct se_device *dev = cmd->se_dev;
2656 	struct se_session *se_sess = cmd->se_sess;
2657 	struct se_lun *se_lun = cmd->se_lun;
2658 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2659 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2660 	int ret, all_reg = 0;
2661 
2662 	if (!se_sess || !se_lun) {
2663 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2664 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2665 		return -EINVAL;
2666 	}
2667 	/*
2668 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2669 	 */
2670 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2671 	if (!pr_reg) {
2672 		pr_err("SPC-3 PR: Unable to locate"
2673 			" PR_REGISTERED *pr_reg for RELEASE\n");
2674 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2675 		return -EINVAL;
2676 	}
2677 	/*
2678 	 * From spc4r17 Section 5.7.11.2 Releasing:
2679 	 *
2680 	 * If there is no persistent reservation or in response to a persistent
2681 	 * reservation release request from a registered I_T nexus that is not a
2682 	 * persistent reservation holder (see 5.7.10), the device server shall
2683 	 * do the following:
2684 	 *
2685 	 *     a) Not release the persistent reservation, if any;
2686 	 *     b) Not remove any registrations; and
2687 	 *     c) Complete the command with GOOD status.
2688 	 */
2689 	spin_lock(&dev->dev_reservation_lock);
2690 	pr_res_holder = dev->dev_pr_res_holder;
2691 	if (!pr_res_holder) {
2692 		/*
2693 		 * No persistent reservation, return GOOD status.
2694 		 */
2695 		spin_unlock(&dev->dev_reservation_lock);
2696 		core_scsi3_put_pr_reg(pr_reg);
2697 		return 0;
2698 	}
2699 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2700 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
2701 		all_reg = 1;
2702 
2703 	if ((all_reg == 0) && (pr_res_holder != pr_reg)) {
2704 		/*
2705 		 * Non 'All Registrants' PR Type cases..
2706 		 * Release request from a registered I_T nexus that is not a
2707 		 * persistent reservation holder. return GOOD status.
2708 		 */
2709 		spin_unlock(&dev->dev_reservation_lock);
2710 		core_scsi3_put_pr_reg(pr_reg);
2711 		return 0;
2712 	}
2713 	/*
2714 	 * From spc4r17 Section 5.7.11.2 Releasing:
2715 	 *
2716 	 * Only the persistent reservation holder (see 5.7.10) is allowed to
2717 	 * release a persistent reservation.
2718 	 *
2719 	 * An application client releases the persistent reservation by issuing
2720 	 * a PERSISTENT RESERVE OUT command with RELEASE service action through
2721 	 * an I_T nexus that is a persistent reservation holder with the
2722 	 * following parameters:
2723 	 *
2724 	 *     a) RESERVATION KEY field set to the value of the reservation key
2725 	 *	  that is registered with the logical unit for the I_T nexus;
2726 	 */
2727 	if (res_key != pr_reg->pr_res_key) {
2728 		pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2729 			" does not match existing SA REGISTER res_key:"
2730 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2731 		spin_unlock(&dev->dev_reservation_lock);
2732 		core_scsi3_put_pr_reg(pr_reg);
2733 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2734 		return -EINVAL;
2735 	}
2736 	/*
2737 	 * From spc4r17 Section 5.7.11.2 Releasing and above:
2738 	 *
2739 	 * b) TYPE field and SCOPE field set to match the persistent
2740 	 *    reservation being released.
2741 	 */
2742 	if ((pr_res_holder->pr_res_type != type) ||
2743 	    (pr_res_holder->pr_res_scope != scope)) {
2744 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2745 		pr_err("SPC-3 PR RELEASE: Attempted to release"
2746 			" reservation from [%s]: %s with different TYPE "
2747 			"and/or SCOPE  while reservation already held by"
2748 			" [%s]: %s, returning RESERVATION_CONFLICT\n",
2749 			cmd->se_tfo->get_fabric_name(),
2750 			se_sess->se_node_acl->initiatorname,
2751 			pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2752 			pr_res_holder->pr_reg_nacl->initiatorname);
2753 
2754 		spin_unlock(&dev->dev_reservation_lock);
2755 		core_scsi3_put_pr_reg(pr_reg);
2756 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2757 		return -EINVAL;
2758 	}
2759 	/*
2760 	 * In response to a persistent reservation release request from the
2761 	 * persistent reservation holder the device server shall perform a
2762 	 * release by doing the following as an uninterrupted series of actions:
2763 	 * a) Release the persistent reservation;
2764 	 * b) Not remove any registration(s);
2765 	 * c) If the released persistent reservation is a registrants only type
2766 	 * or all registrants type persistent reservation,
2767 	 *    the device server shall establish a unit attention condition for
2768 	 *    the initiator port associated with every regis-
2769 	 *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2770 	 *    RESERVE OUT command with RELEASE service action was received,
2771 	 *    with the additional sense code set to RESERVATIONS RELEASED; and
2772 	 * d) If the persistent reservation is of any other type, the device
2773 	 *    server shall not establish a unit attention condition.
2774 	 */
2775 	__core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2776 			pr_reg, 1);
2777 
2778 	spin_unlock(&dev->dev_reservation_lock);
2779 
2780 	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2781 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2782 	    (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2783 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2784 		/*
2785 		 * If no UNIT ATTENTION conditions will be established for
2786 		 * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2787 		 * go ahead and check for APTPL=1 update+write below
2788 		 */
2789 		goto write_aptpl;
2790 	}
2791 
2792 	spin_lock(&pr_tmpl->registration_lock);
2793 	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2794 			pr_reg_list) {
2795 		/*
2796 		 * Do not establish a UNIT ATTENTION condition
2797 		 * for the calling I_T Nexus
2798 		 */
2799 		if (pr_reg_p == pr_reg)
2800 			continue;
2801 
2802 		core_scsi3_ua_allocate(pr_reg_p->pr_reg_nacl,
2803 				pr_reg_p->pr_res_mapped_lun,
2804 				0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2805 	}
2806 	spin_unlock(&pr_tmpl->registration_lock);
2807 
2808 write_aptpl:
2809 	if (pr_tmpl->pr_aptpl_active) {
2810 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2811 				&pr_reg->pr_aptpl_buf[0],
2812 				pr_tmpl->pr_aptpl_buf_len);
2813 		if (!ret)
2814 			pr_debug("SPC-3 PR: Updated APTPL metadata for RELEASE\n");
2815 	}
2816 
2817 	core_scsi3_put_pr_reg(pr_reg);
2818 	return 0;
2819 }
2820 
2821 static int core_scsi3_emulate_pro_clear(
2822 	struct se_cmd *cmd,
2823 	u64 res_key)
2824 {
2825 	struct se_device *dev = cmd->se_dev;
2826 	struct se_node_acl *pr_reg_nacl;
2827 	struct se_session *se_sess = cmd->se_sess;
2828 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2829 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2830 	u32 pr_res_mapped_lun = 0;
2831 	int calling_it_nexus = 0;
2832 	/*
2833 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2834 	 */
2835 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2836 			se_sess->se_node_acl, se_sess);
2837 	if (!pr_reg_n) {
2838 		pr_err("SPC-3 PR: Unable to locate"
2839 			" PR_REGISTERED *pr_reg for CLEAR\n");
2840 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2841 		return -EINVAL;
2842 	}
2843 	/*
2844 	 * From spc4r17 section 5.7.11.6, Clearing:
2845 	 *
2846 	 * Any application client may release the persistent reservation and
2847 	 * remove all registrations from a device server by issuing a
2848 	 * PERSISTENT RESERVE OUT command with CLEAR service action through a
2849 	 * registered I_T nexus with the following parameter:
2850 	 *
2851 	 *	a) RESERVATION KEY field set to the value of the reservation key
2852 	 * 	   that is registered with the logical unit for the I_T nexus.
2853 	 */
2854 	if (res_key != pr_reg_n->pr_res_key) {
2855 		pr_err("SPC-3 PR REGISTER: Received"
2856 			" res_key: 0x%016Lx does not match"
2857 			" existing SA REGISTER res_key:"
2858 			" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2859 		core_scsi3_put_pr_reg(pr_reg_n);
2860 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2861 		return -EINVAL;
2862 	}
2863 	/*
2864 	 * a) Release the persistent reservation, if any;
2865 	 */
2866 	spin_lock(&dev->dev_reservation_lock);
2867 	pr_res_holder = dev->dev_pr_res_holder;
2868 	if (pr_res_holder) {
2869 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2870 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
2871 			pr_res_holder, 0);
2872 	}
2873 	spin_unlock(&dev->dev_reservation_lock);
2874 	/*
2875 	 * b) Remove all registration(s) (see spc4r17 5.7.7);
2876 	 */
2877 	spin_lock(&pr_tmpl->registration_lock);
2878 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2879 			&pr_tmpl->registration_list, pr_reg_list) {
2880 
2881 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2882 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2883 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2884 		__core_scsi3_free_registration(dev, pr_reg, NULL,
2885 					calling_it_nexus);
2886 		/*
2887 		 * e) Establish a unit attention condition for the initiator
2888 		 *    port associated with every registered I_T nexus other
2889 		 *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2890 		 *    command with CLEAR service action was received, with the
2891 		 *    additional sense code set to RESERVATIONS PREEMPTED.
2892 		 */
2893 		if (!calling_it_nexus)
2894 			core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun,
2895 				0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2896 	}
2897 	spin_unlock(&pr_tmpl->registration_lock);
2898 
2899 	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2900 		cmd->se_tfo->get_fabric_name());
2901 
2902 	if (pr_tmpl->pr_aptpl_active) {
2903 		core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
2904 		pr_debug("SPC-3 PR: Updated APTPL metadata"
2905 				" for CLEAR\n");
2906 	}
2907 
2908 	core_scsi3_pr_generation(dev);
2909 	return 0;
2910 }
2911 
2912 /*
2913  * Called with struct se_device->dev_reservation_lock held.
2914  */
2915 static void __core_scsi3_complete_pro_preempt(
2916 	struct se_device *dev,
2917 	struct t10_pr_registration *pr_reg,
2918 	struct list_head *preempt_and_abort_list,
2919 	int type,
2920 	int scope,
2921 	int abort)
2922 {
2923 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2924 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2925 	char i_buf[PR_REG_ISID_ID_LEN];
2926 	int prf_isid;
2927 
2928 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2929 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2930 				PR_REG_ISID_ID_LEN);
2931 	/*
2932 	 * Do an implict RELEASE of the existing reservation.
2933 	 */
2934 	if (dev->dev_pr_res_holder)
2935 		__core_scsi3_complete_pro_release(dev, nacl,
2936 				dev->dev_pr_res_holder, 0);
2937 
2938 	dev->dev_pr_res_holder = pr_reg;
2939 	pr_reg->pr_res_holder = 1;
2940 	pr_reg->pr_res_type = type;
2941 	pr_reg->pr_res_scope = scope;
2942 
2943 	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2944 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2945 		tfo->get_fabric_name(), (abort) ? "_AND_ABORT" : "",
2946 		core_scsi3_pr_dump_type(type),
2947 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2948 	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2949 		tfo->get_fabric_name(), (abort) ? "_AND_ABORT" : "",
2950 		nacl->initiatorname, (prf_isid) ? &i_buf[0] : "");
2951 	/*
2952 	 * For PREEMPT_AND_ABORT, add the preempting reservation's
2953 	 * struct t10_pr_registration to the list that will be compared
2954 	 * against received CDBs..
2955 	 */
2956 	if (preempt_and_abort_list)
2957 		list_add_tail(&pr_reg->pr_reg_abort_list,
2958 				preempt_and_abort_list);
2959 }
2960 
2961 static void core_scsi3_release_preempt_and_abort(
2962 	struct list_head *preempt_and_abort_list,
2963 	struct t10_pr_registration *pr_reg_holder)
2964 {
2965 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2966 
2967 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2968 				pr_reg_abort_list) {
2969 
2970 		list_del(&pr_reg->pr_reg_abort_list);
2971 		if (pr_reg_holder == pr_reg)
2972 			continue;
2973 		if (pr_reg->pr_res_holder) {
2974 			pr_warn("pr_reg->pr_res_holder still set\n");
2975 			continue;
2976 		}
2977 
2978 		pr_reg->pr_reg_deve = NULL;
2979 		pr_reg->pr_reg_nacl = NULL;
2980 		kfree(pr_reg->pr_aptpl_buf);
2981 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
2982 	}
2983 }
2984 
2985 static int core_scsi3_pro_preempt(
2986 	struct se_cmd *cmd,
2987 	int type,
2988 	int scope,
2989 	u64 res_key,
2990 	u64 sa_res_key,
2991 	int abort)
2992 {
2993 	struct se_device *dev = cmd->se_dev;
2994 	struct se_dev_entry *se_deve;
2995 	struct se_node_acl *pr_reg_nacl;
2996 	struct se_session *se_sess = cmd->se_sess;
2997 	struct list_head preempt_and_abort_list;
2998 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2999 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
3000 	u32 pr_res_mapped_lun = 0;
3001 	int all_reg = 0, calling_it_nexus = 0, released_regs = 0;
3002 	int prh_type = 0, prh_scope = 0, ret;
3003 
3004 	if (!se_sess) {
3005 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3006 		return -EINVAL;
3007 	}
3008 
3009 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
3010 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3011 				se_sess);
3012 	if (!pr_reg_n) {
3013 		pr_err("SPC-3 PR: Unable to locate"
3014 			" PR_REGISTERED *pr_reg for PREEMPT%s\n",
3015 			(abort) ? "_AND_ABORT" : "");
3016 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3017 		return -EINVAL;
3018 	}
3019 	if (pr_reg_n->pr_res_key != res_key) {
3020 		core_scsi3_put_pr_reg(pr_reg_n);
3021 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3022 		return -EINVAL;
3023 	}
3024 	if (scope != PR_SCOPE_LU_SCOPE) {
3025 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
3026 		core_scsi3_put_pr_reg(pr_reg_n);
3027 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3028 		return -EINVAL;
3029 	}
3030 	INIT_LIST_HEAD(&preempt_and_abort_list);
3031 
3032 	spin_lock(&dev->dev_reservation_lock);
3033 	pr_res_holder = dev->dev_pr_res_holder;
3034 	if (pr_res_holder &&
3035 	   ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3036 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
3037 		all_reg = 1;
3038 
3039 	if (!all_reg && !sa_res_key) {
3040 		spin_unlock(&dev->dev_reservation_lock);
3041 		core_scsi3_put_pr_reg(pr_reg_n);
3042 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3043 		return -EINVAL;
3044 	}
3045 	/*
3046 	 * From spc4r17, section 5.7.11.4.4 Removing Registrations:
3047 	 *
3048 	 * If the SERVICE ACTION RESERVATION KEY field does not identify a
3049 	 * persistent reservation holder or there is no persistent reservation
3050 	 * holder (i.e., there is no persistent reservation), then the device
3051 	 * server shall perform a preempt by doing the following in an
3052 	 * uninterrupted series of actions. (See below..)
3053 	 */
3054 	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
3055 		/*
3056 		 * No existing or SA Reservation Key matching reservations..
3057 		 *
3058 		 * PROUT SA PREEMPT with All Registrant type reservations are
3059 		 * allowed to be processed without a matching SA Reservation Key
3060 		 */
3061 		spin_lock(&pr_tmpl->registration_lock);
3062 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3063 				&pr_tmpl->registration_list, pr_reg_list) {
3064 			/*
3065 			 * Removing of registrations in non all registrants
3066 			 * type reservations without a matching SA reservation
3067 			 * key.
3068 			 *
3069 			 * a) Remove the registrations for all I_T nexuses
3070 			 *    specified by the SERVICE ACTION RESERVATION KEY
3071 			 *    field;
3072 			 * b) Ignore the contents of the SCOPE and TYPE fields;
3073 			 * c) Process tasks as defined in 5.7.1; and
3074 			 * d) Establish a unit attention condition for the
3075 			 *    initiator port associated with every I_T nexus
3076 			 *    that lost its registration other than the I_T
3077 			 *    nexus on which the PERSISTENT RESERVE OUT command
3078 			 *    was received, with the additional sense code set
3079 			 *    to REGISTRATIONS PREEMPTED.
3080 			 */
3081 			if (!all_reg) {
3082 				if (pr_reg->pr_res_key != sa_res_key)
3083 					continue;
3084 
3085 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3086 				pr_reg_nacl = pr_reg->pr_reg_nacl;
3087 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3088 				__core_scsi3_free_registration(dev, pr_reg,
3089 					(abort) ? &preempt_and_abort_list :
3090 						NULL, calling_it_nexus);
3091 				released_regs++;
3092 			} else {
3093 				/*
3094 				 * Case for any existing all registrants type
3095 				 * reservation, follow logic in spc4r17 section
3096 				 * 5.7.11.4 Preempting, Table 52 and Figure 7.
3097 				 *
3098 				 * For a ZERO SA Reservation key, release
3099 				 * all other registrations and do an implict
3100 				 * release of active persistent reservation.
3101 				 *
3102 				 * For a non-ZERO SA Reservation key, only
3103 				 * release the matching reservation key from
3104 				 * registrations.
3105 				 */
3106 				if ((sa_res_key) &&
3107 				     (pr_reg->pr_res_key != sa_res_key))
3108 					continue;
3109 
3110 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3111 				if (calling_it_nexus)
3112 					continue;
3113 
3114 				pr_reg_nacl = pr_reg->pr_reg_nacl;
3115 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3116 				__core_scsi3_free_registration(dev, pr_reg,
3117 					(abort) ? &preempt_and_abort_list :
3118 						NULL, 0);
3119 				released_regs++;
3120 			}
3121 			if (!calling_it_nexus)
3122 				core_scsi3_ua_allocate(pr_reg_nacl,
3123 					pr_res_mapped_lun, 0x2A,
3124 					ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3125 		}
3126 		spin_unlock(&pr_tmpl->registration_lock);
3127 		/*
3128 		 * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
3129 		 * a PREEMPT AND ABORT service action sets the SERVICE ACTION
3130 		 * RESERVATION KEY field to a value that does not match any
3131 		 * registered reservation key, then the device server shall
3132 		 * complete the command with RESERVATION CONFLICT status.
3133 		 */
3134 		if (!released_regs) {
3135 			spin_unlock(&dev->dev_reservation_lock);
3136 			core_scsi3_put_pr_reg(pr_reg_n);
3137 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3138 			return -EINVAL;
3139 		}
3140 		/*
3141 		 * For an existing all registrants type reservation
3142 		 * with a zero SA rservation key, preempt the existing
3143 		 * reservation with the new PR type and scope.
3144 		 */
3145 		if (pr_res_holder && all_reg && !(sa_res_key)) {
3146 			__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3147 				(abort) ? &preempt_and_abort_list : NULL,
3148 				type, scope, abort);
3149 
3150 			if (abort)
3151 				core_scsi3_release_preempt_and_abort(
3152 					&preempt_and_abort_list, pr_reg_n);
3153 		}
3154 		spin_unlock(&dev->dev_reservation_lock);
3155 
3156 		if (pr_tmpl->pr_aptpl_active) {
3157 			ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3158 					&pr_reg_n->pr_aptpl_buf[0],
3159 					pr_tmpl->pr_aptpl_buf_len);
3160 			if (!ret)
3161 				pr_debug("SPC-3 PR: Updated APTPL"
3162 					" metadata for  PREEMPT%s\n", (abort) ?
3163 					"_AND_ABORT" : "");
3164 		}
3165 
3166 		core_scsi3_put_pr_reg(pr_reg_n);
3167 		core_scsi3_pr_generation(cmd->se_dev);
3168 		return 0;
3169 	}
3170 	/*
3171 	 * The PREEMPTing SA reservation key matches that of the
3172 	 * existing persistent reservation, first, we check if
3173 	 * we are preempting our own reservation.
3174 	 * From spc4r17, section 5.7.11.4.3 Preempting
3175 	 * persistent reservations and registration handling
3176 	 *
3177 	 * If an all registrants persistent reservation is not
3178 	 * present, it is not an error for the persistent
3179 	 * reservation holder to preempt itself (i.e., a
3180 	 * PERSISTENT RESERVE OUT with a PREEMPT service action
3181 	 * or a PREEMPT AND ABORT service action with the
3182 	 * SERVICE ACTION RESERVATION KEY value equal to the
3183 	 * persistent reservation holder's reservation key that
3184 	 * is received from the persistent reservation holder).
3185 	 * In that case, the device server shall establish the
3186 	 * new persistent reservation and maintain the
3187 	 * registration.
3188 	 */
3189 	prh_type = pr_res_holder->pr_res_type;
3190 	prh_scope = pr_res_holder->pr_res_scope;
3191 	/*
3192 	 * If the SERVICE ACTION RESERVATION KEY field identifies a
3193 	 * persistent reservation holder (see 5.7.10), the device
3194 	 * server shall perform a preempt by doing the following as
3195 	 * an uninterrupted series of actions:
3196 	 *
3197 	 * a) Release the persistent reservation for the holder
3198 	 *    identified by the SERVICE ACTION RESERVATION KEY field;
3199 	 */
3200 	if (pr_reg_n != pr_res_holder)
3201 		__core_scsi3_complete_pro_release(dev,
3202 				pr_res_holder->pr_reg_nacl,
3203 				dev->dev_pr_res_holder, 0);
3204 	/*
3205 	 * b) Remove the registrations for all I_T nexuses identified
3206 	 *    by the SERVICE ACTION RESERVATION KEY field, except the
3207 	 *    I_T nexus that is being used for the PERSISTENT RESERVE
3208 	 *    OUT command. If an all registrants persistent reservation
3209 	 *    is present and the SERVICE ACTION RESERVATION KEY field
3210 	 *    is set to zero, then all registrations shall be removed
3211 	 *    except for that of the I_T nexus that is being used for
3212 	 *    the PERSISTENT RESERVE OUT command;
3213 	 */
3214 	spin_lock(&pr_tmpl->registration_lock);
3215 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3216 			&pr_tmpl->registration_list, pr_reg_list) {
3217 
3218 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3219 		if (calling_it_nexus)
3220 			continue;
3221 
3222 		if (pr_reg->pr_res_key != sa_res_key)
3223 			continue;
3224 
3225 		pr_reg_nacl = pr_reg->pr_reg_nacl;
3226 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3227 		__core_scsi3_free_registration(dev, pr_reg,
3228 				(abort) ? &preempt_and_abort_list : NULL,
3229 				calling_it_nexus);
3230 		/*
3231 		 * e) Establish a unit attention condition for the initiator
3232 		 *    port associated with every I_T nexus that lost its
3233 		 *    persistent reservation and/or registration, with the
3234 		 *    additional sense code set to REGISTRATIONS PREEMPTED;
3235 		 */
3236 		core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3237 				ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3238 	}
3239 	spin_unlock(&pr_tmpl->registration_lock);
3240 	/*
3241 	 * c) Establish a persistent reservation for the preempting
3242 	 *    I_T nexus using the contents of the SCOPE and TYPE fields;
3243 	 */
3244 	__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3245 			(abort) ? &preempt_and_abort_list : NULL,
3246 			type, scope, abort);
3247 	/*
3248 	 * d) Process tasks as defined in 5.7.1;
3249 	 * e) See above..
3250 	 * f) If the type or scope has changed, then for every I_T nexus
3251 	 *    whose reservation key was not removed, except for the I_T
3252 	 *    nexus on which the PERSISTENT RESERVE OUT command was
3253 	 *    received, the device server shall establish a unit
3254 	 *    attention condition for the initiator port associated with
3255 	 *    that I_T nexus, with the additional sense code set to
3256 	 *    RESERVATIONS RELEASED. If the type or scope have not
3257 	 *    changed, then no unit attention condition(s) shall be
3258 	 *    established for this reason.
3259 	 */
3260 	if ((prh_type != type) || (prh_scope != scope)) {
3261 		spin_lock(&pr_tmpl->registration_lock);
3262 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3263 				&pr_tmpl->registration_list, pr_reg_list) {
3264 
3265 			calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3266 			if (calling_it_nexus)
3267 				continue;
3268 
3269 			core_scsi3_ua_allocate(pr_reg->pr_reg_nacl,
3270 					pr_reg->pr_res_mapped_lun, 0x2A,
3271 					ASCQ_2AH_RESERVATIONS_RELEASED);
3272 		}
3273 		spin_unlock(&pr_tmpl->registration_lock);
3274 	}
3275 	spin_unlock(&dev->dev_reservation_lock);
3276 	/*
3277 	 * Call LUN_RESET logic upon list of struct t10_pr_registration,
3278 	 * All received CDBs for the matching existing reservation and
3279 	 * registrations undergo ABORT_TASK logic.
3280 	 *
3281 	 * From there, core_scsi3_release_preempt_and_abort() will
3282 	 * release every registration in the list (which have already
3283 	 * been removed from the primary pr_reg list), except the
3284 	 * new persistent reservation holder, the calling Initiator Port.
3285 	 */
3286 	if (abort) {
3287 		core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3288 		core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3289 						pr_reg_n);
3290 	}
3291 
3292 	if (pr_tmpl->pr_aptpl_active) {
3293 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3294 				&pr_reg_n->pr_aptpl_buf[0],
3295 				pr_tmpl->pr_aptpl_buf_len);
3296 		if (!ret)
3297 			pr_debug("SPC-3 PR: Updated APTPL metadata for PREEMPT"
3298 				"%s\n", (abort) ? "_AND_ABORT" : "");
3299 	}
3300 
3301 	core_scsi3_put_pr_reg(pr_reg_n);
3302 	core_scsi3_pr_generation(cmd->se_dev);
3303 	return 0;
3304 }
3305 
3306 static int core_scsi3_emulate_pro_preempt(
3307 	struct se_cmd *cmd,
3308 	int type,
3309 	int scope,
3310 	u64 res_key,
3311 	u64 sa_res_key,
3312 	int abort)
3313 {
3314 	int ret = 0;
3315 
3316 	switch (type) {
3317 	case PR_TYPE_WRITE_EXCLUSIVE:
3318 	case PR_TYPE_EXCLUSIVE_ACCESS:
3319 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3320 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3321 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3322 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3323 		ret = core_scsi3_pro_preempt(cmd, type, scope,
3324 				res_key, sa_res_key, abort);
3325 		break;
3326 	default:
3327 		pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3328 			" Type: 0x%02x\n", (abort) ? "_AND_ABORT" : "", type);
3329 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3330 		return -EINVAL;
3331 	}
3332 
3333 	return ret;
3334 }
3335 
3336 
3337 static int core_scsi3_emulate_pro_register_and_move(
3338 	struct se_cmd *cmd,
3339 	u64 res_key,
3340 	u64 sa_res_key,
3341 	int aptpl,
3342 	int unreg)
3343 {
3344 	struct se_session *se_sess = cmd->se_sess;
3345 	struct se_device *dev = cmd->se_dev;
3346 	struct se_dev_entry *se_deve, *dest_se_deve = NULL;
3347 	struct se_lun *se_lun = cmd->se_lun;
3348 	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3349 	struct se_port *se_port;
3350 	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3351 	struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3352 	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3353 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
3354 	unsigned char *buf;
3355 	unsigned char *initiator_str;
3356 	char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
3357 	u32 tid_len, tmp_tid_len;
3358 	int new_reg = 0, type, scope, ret, matching_iname, prf_isid;
3359 	unsigned short rtpi;
3360 	unsigned char proto_ident;
3361 
3362 	if (!se_sess || !se_lun) {
3363 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3364 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3365 		return -EINVAL;
3366 	}
3367 	memset(dest_iport, 0, 64);
3368 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3369 	se_tpg = se_sess->se_tpg;
3370 	tf_ops = se_tpg->se_tpg_tfo;
3371 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
3372 	/*
3373 	 * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3374 	 *	Register behaviors for a REGISTER AND MOVE service action
3375 	 *
3376 	 * Locate the existing *pr_reg via struct se_node_acl pointers
3377 	 */
3378 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3379 				se_sess);
3380 	if (!pr_reg) {
3381 		pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3382 			" *pr_reg for REGISTER_AND_MOVE\n");
3383 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3384 		return -EINVAL;
3385 	}
3386 	/*
3387 	 * The provided reservation key much match the existing reservation key
3388 	 * provided during this initiator's I_T nexus registration.
3389 	 */
3390 	if (res_key != pr_reg->pr_res_key) {
3391 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3392 			" res_key: 0x%016Lx does not match existing SA REGISTER"
3393 			" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3394 		core_scsi3_put_pr_reg(pr_reg);
3395 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3396 		return -EINVAL;
3397 	}
3398 	/*
3399 	 * The service active reservation key needs to be non zero
3400 	 */
3401 	if (!sa_res_key) {
3402 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3403 			" sa_res_key\n");
3404 		core_scsi3_put_pr_reg(pr_reg);
3405 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3406 		return -EINVAL;
3407 	}
3408 
3409 	/*
3410 	 * Determine the Relative Target Port Identifier where the reservation
3411 	 * will be moved to for the TransportID containing SCSI initiator WWN
3412 	 * information.
3413 	 */
3414 	buf = transport_kmap_data_sg(cmd);
3415 	rtpi = (buf[18] & 0xff) << 8;
3416 	rtpi |= buf[19] & 0xff;
3417 	tid_len = (buf[20] & 0xff) << 24;
3418 	tid_len |= (buf[21] & 0xff) << 16;
3419 	tid_len |= (buf[22] & 0xff) << 8;
3420 	tid_len |= buf[23] & 0xff;
3421 	transport_kunmap_data_sg(cmd);
3422 	buf = NULL;
3423 
3424 	if ((tid_len + 24) != cmd->data_length) {
3425 		pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3426 			" does not equal CDB data_length: %u\n", tid_len,
3427 			cmd->data_length);
3428 		core_scsi3_put_pr_reg(pr_reg);
3429 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3430 		return -EINVAL;
3431 	}
3432 
3433 	spin_lock(&dev->se_port_lock);
3434 	list_for_each_entry(se_port, &dev->dev_sep_list, sep_list) {
3435 		if (se_port->sep_rtpi != rtpi)
3436 			continue;
3437 		dest_se_tpg = se_port->sep_tpg;
3438 		if (!dest_se_tpg)
3439 			continue;
3440 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3441 		if (!dest_tf_ops)
3442 			continue;
3443 
3444 		atomic_inc(&dest_se_tpg->tpg_pr_ref_count);
3445 		smp_mb__after_atomic_inc();
3446 		spin_unlock(&dev->se_port_lock);
3447 
3448 		ret = core_scsi3_tpg_depend_item(dest_se_tpg);
3449 		if (ret != 0) {
3450 			pr_err("core_scsi3_tpg_depend_item() failed"
3451 				" for dest_se_tpg\n");
3452 			atomic_dec(&dest_se_tpg->tpg_pr_ref_count);
3453 			smp_mb__after_atomic_dec();
3454 			core_scsi3_put_pr_reg(pr_reg);
3455 			cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3456 			return -EINVAL;
3457 		}
3458 
3459 		spin_lock(&dev->se_port_lock);
3460 		break;
3461 	}
3462 	spin_unlock(&dev->se_port_lock);
3463 
3464 	if (!dest_se_tpg || !dest_tf_ops) {
3465 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3466 			" fabric ops from Relative Target Port Identifier:"
3467 			" %hu\n", rtpi);
3468 		core_scsi3_put_pr_reg(pr_reg);
3469 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3470 		return -EINVAL;
3471 	}
3472 
3473 	buf = transport_kmap_data_sg(cmd);
3474 	proto_ident = (buf[24] & 0x0f);
3475 #if 0
3476 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3477 			" 0x%02x\n", proto_ident);
3478 #endif
3479 	if (proto_ident != dest_tf_ops->get_fabric_proto_ident(dest_se_tpg)) {
3480 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3481 			" proto_ident: 0x%02x does not match ident: 0x%02x"
3482 			" from fabric: %s\n", proto_ident,
3483 			dest_tf_ops->get_fabric_proto_ident(dest_se_tpg),
3484 			dest_tf_ops->get_fabric_name());
3485 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3486 		ret = -EINVAL;
3487 		goto out;
3488 	}
3489 	if (dest_tf_ops->tpg_parse_pr_out_transport_id == NULL) {
3490 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Fabric does not"
3491 			" containg a valid tpg_parse_pr_out_transport_id"
3492 			" function pointer\n");
3493 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3494 		ret = -EINVAL;
3495 		goto out;
3496 	}
3497 	initiator_str = dest_tf_ops->tpg_parse_pr_out_transport_id(dest_se_tpg,
3498 			(const char *)&buf[24], &tmp_tid_len, &iport_ptr);
3499 	if (!initiator_str) {
3500 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3501 			" initiator_str from Transport ID\n");
3502 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3503 		ret = -EINVAL;
3504 		goto out;
3505 	}
3506 
3507 	transport_kunmap_data_sg(cmd);
3508 	buf = NULL;
3509 
3510 	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3511 		" %s\n", dest_tf_ops->get_fabric_name(), (iport_ptr != NULL) ?
3512 		"port" : "device", initiator_str, (iport_ptr != NULL) ?
3513 		iport_ptr : "");
3514 	/*
3515 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3516 	 * action specifies a TransportID that is the same as the initiator port
3517 	 * of the I_T nexus for the command received, then the command shall
3518 	 * be terminated with CHECK CONDITION status, with the sense key set to
3519 	 * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3520 	 * IN PARAMETER LIST.
3521 	 */
3522 	pr_reg_nacl = pr_reg->pr_reg_nacl;
3523 	matching_iname = (!strcmp(initiator_str,
3524 				  pr_reg_nacl->initiatorname)) ? 1 : 0;
3525 	if (!matching_iname)
3526 		goto after_iport_check;
3527 
3528 	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3529 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3530 			" matches: %s on received I_T Nexus\n", initiator_str,
3531 			pr_reg_nacl->initiatorname);
3532 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3533 		ret = -EINVAL;
3534 		goto out;
3535 	}
3536 	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3537 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3538 			" matches: %s %s on received I_T Nexus\n",
3539 			initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3540 			pr_reg->pr_reg_isid);
3541 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3542 		ret = -EINVAL;
3543 		goto out;
3544 	}
3545 after_iport_check:
3546 	/*
3547 	 * Locate the destination struct se_node_acl from the received Transport ID
3548 	 */
3549 	spin_lock_irq(&dest_se_tpg->acl_node_lock);
3550 	dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3551 				initiator_str);
3552 	if (dest_node_acl) {
3553 		atomic_inc(&dest_node_acl->acl_pr_ref_count);
3554 		smp_mb__after_atomic_inc();
3555 	}
3556 	spin_unlock_irq(&dest_se_tpg->acl_node_lock);
3557 
3558 	if (!dest_node_acl) {
3559 		pr_err("Unable to locate %s dest_node_acl for"
3560 			" TransportID%s\n", dest_tf_ops->get_fabric_name(),
3561 			initiator_str);
3562 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3563 		ret = -EINVAL;
3564 		goto out;
3565 	}
3566 	ret = core_scsi3_nodeacl_depend_item(dest_node_acl);
3567 	if (ret != 0) {
3568 		pr_err("core_scsi3_nodeacl_depend_item() for"
3569 			" dest_node_acl\n");
3570 		atomic_dec(&dest_node_acl->acl_pr_ref_count);
3571 		smp_mb__after_atomic_dec();
3572 		dest_node_acl = NULL;
3573 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3574 		ret = -EINVAL;
3575 		goto out;
3576 	}
3577 #if 0
3578 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3579 		" %s from TransportID\n", dest_tf_ops->get_fabric_name(),
3580 		dest_node_acl->initiatorname);
3581 #endif
3582 	/*
3583 	 * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3584 	 * PORT IDENTIFIER.
3585 	 */
3586 	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3587 	if (!dest_se_deve) {
3588 		pr_err("Unable to locate %s dest_se_deve from RTPI:"
3589 			" %hu\n",  dest_tf_ops->get_fabric_name(), rtpi);
3590 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3591 		ret = -EINVAL;
3592 		goto out;
3593 	}
3594 
3595 	ret = core_scsi3_lunacl_depend_item(dest_se_deve);
3596 	if (ret < 0) {
3597 		pr_err("core_scsi3_lunacl_depend_item() failed\n");
3598 		atomic_dec(&dest_se_deve->pr_ref_count);
3599 		smp_mb__after_atomic_dec();
3600 		dest_se_deve = NULL;
3601 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3602 		ret = -EINVAL;
3603 		goto out;
3604 	}
3605 #if 0
3606 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3607 		" ACL for dest_se_deve->mapped_lun: %u\n",
3608 		dest_tf_ops->get_fabric_name(), dest_node_acl->initiatorname,
3609 		dest_se_deve->mapped_lun);
3610 #endif
3611 	/*
3612 	 * A persistent reservation needs to already existing in order to
3613 	 * successfully complete the REGISTER_AND_MOVE service action..
3614 	 */
3615 	spin_lock(&dev->dev_reservation_lock);
3616 	pr_res_holder = dev->dev_pr_res_holder;
3617 	if (!pr_res_holder) {
3618 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3619 			" currently held\n");
3620 		spin_unlock(&dev->dev_reservation_lock);
3621 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3622 		ret = -EINVAL;
3623 		goto out;
3624 	}
3625 	/*
3626 	 * The received on I_T Nexus must be the reservation holder.
3627 	 *
3628 	 * From spc4r17 section 5.7.8  Table 50 --
3629 	 * 	Register behaviors for a REGISTER AND MOVE service action
3630 	 */
3631 	if (pr_res_holder != pr_reg) {
3632 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3633 			" Nexus is not reservation holder\n");
3634 		spin_unlock(&dev->dev_reservation_lock);
3635 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3636 		ret = -EINVAL;
3637 		goto out;
3638 	}
3639 	/*
3640 	 * From spc4r17 section 5.7.8: registering and moving reservation
3641 	 *
3642 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3643 	 * action is received and the established persistent reservation is a
3644 	 * Write Exclusive - All Registrants type or Exclusive Access -
3645 	 * All Registrants type reservation, then the command shall be completed
3646 	 * with RESERVATION CONFLICT status.
3647 	 */
3648 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3649 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3650 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3651 			" reservation for type: %s\n",
3652 			core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3653 		spin_unlock(&dev->dev_reservation_lock);
3654 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3655 		ret = -EINVAL;
3656 		goto out;
3657 	}
3658 	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3659 	/*
3660 	 * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3661 	 */
3662 	type = pr_res_holder->pr_res_type;
3663 	scope = pr_res_holder->pr_res_type;
3664 	/*
3665 	 * c) Associate the reservation key specified in the SERVICE ACTION
3666 	 *    RESERVATION KEY field with the I_T nexus specified as the
3667 	 *    destination of the register and move, where:
3668 	 *    A) The I_T nexus is specified by the TransportID and the
3669 	 *	 RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3670 	 *    B) Regardless of the TransportID format used, the association for
3671 	 *       the initiator port is based on either the initiator port name
3672 	 *       (see 3.1.71) on SCSI transport protocols where port names are
3673 	 *       required or the initiator port identifier (see 3.1.70) on SCSI
3674 	 *       transport protocols where port names are not required;
3675 	 * d) Register the reservation key specified in the SERVICE ACTION
3676 	 *    RESERVATION KEY field;
3677 	 * e) Retain the reservation key specified in the SERVICE ACTION
3678 	 *    RESERVATION KEY field and associated information;
3679 	 *
3680 	 * Also, It is not an error for a REGISTER AND MOVE service action to
3681 	 * register an I_T nexus that is already registered with the same
3682 	 * reservation key or a different reservation key.
3683 	 */
3684 	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3685 					iport_ptr);
3686 	if (!dest_pr_reg) {
3687 		ret = core_scsi3_alloc_registration(cmd->se_dev,
3688 				dest_node_acl, dest_se_deve, iport_ptr,
3689 				sa_res_key, 0, aptpl, 2, 1);
3690 		if (ret != 0) {
3691 			spin_unlock(&dev->dev_reservation_lock);
3692 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3693 			ret = -EINVAL;
3694 			goto out;
3695 		}
3696 		dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3697 						iport_ptr);
3698 		new_reg = 1;
3699 	}
3700 	/*
3701 	 * f) Release the persistent reservation for the persistent reservation
3702 	 *    holder (i.e., the I_T nexus on which the
3703 	 */
3704 	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
3705 			dev->dev_pr_res_holder, 0);
3706 	/*
3707 	 * g) Move the persistent reservation to the specified I_T nexus using
3708 	 *    the same scope and type as the persistent reservation released in
3709 	 *    item f); and
3710 	 */
3711 	dev->dev_pr_res_holder = dest_pr_reg;
3712 	dest_pr_reg->pr_res_holder = 1;
3713 	dest_pr_reg->pr_res_type = type;
3714 	pr_reg->pr_res_scope = scope;
3715 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
3716 				PR_REG_ISID_ID_LEN);
3717 	/*
3718 	 * Increment PRGeneration for existing registrations..
3719 	 */
3720 	if (!new_reg)
3721 		dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3722 	spin_unlock(&dev->dev_reservation_lock);
3723 
3724 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3725 		" created new reservation holder TYPE: %s on object RTPI:"
3726 		" %hu  PRGeneration: 0x%08x\n", dest_tf_ops->get_fabric_name(),
3727 		core_scsi3_pr_dump_type(type), rtpi,
3728 		dest_pr_reg->pr_res_generation);
3729 	pr_debug("SPC-3 PR Successfully moved reservation from"
3730 		" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3731 		tf_ops->get_fabric_name(), pr_reg_nacl->initiatorname,
3732 		(prf_isid) ? &i_buf[0] : "", dest_tf_ops->get_fabric_name(),
3733 		dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3734 		iport_ptr : "");
3735 	/*
3736 	 * It is now safe to release configfs group dependencies for destination
3737 	 * of Transport ID Initiator Device/Port Identifier
3738 	 */
3739 	core_scsi3_lunacl_undepend_item(dest_se_deve);
3740 	core_scsi3_nodeacl_undepend_item(dest_node_acl);
3741 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3742 	/*
3743 	 * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3744 	 * nexus on which PERSISTENT RESERVE OUT command was received.
3745 	 */
3746 	if (unreg) {
3747 		spin_lock(&pr_tmpl->registration_lock);
3748 		__core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3749 		spin_unlock(&pr_tmpl->registration_lock);
3750 	} else
3751 		core_scsi3_put_pr_reg(pr_reg);
3752 
3753 	/*
3754 	 * Clear the APTPL metadata if APTPL has been disabled, otherwise
3755 	 * write out the updated metadata to struct file for this SCSI device.
3756 	 */
3757 	if (!aptpl) {
3758 		pr_tmpl->pr_aptpl_active = 0;
3759 		core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
3760 		pr_debug("SPC-3 PR: Set APTPL Bit Deactivated for"
3761 				" REGISTER_AND_MOVE\n");
3762 	} else {
3763 		pr_tmpl->pr_aptpl_active = 1;
3764 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3765 				&dest_pr_reg->pr_aptpl_buf[0],
3766 				pr_tmpl->pr_aptpl_buf_len);
3767 		if (!ret)
3768 			pr_debug("SPC-3 PR: Set APTPL Bit Activated for"
3769 					" REGISTER_AND_MOVE\n");
3770 	}
3771 
3772 	transport_kunmap_data_sg(cmd);
3773 
3774 	core_scsi3_put_pr_reg(dest_pr_reg);
3775 	return 0;
3776 out:
3777 	if (buf)
3778 		transport_kunmap_data_sg(cmd);
3779 	if (dest_se_deve)
3780 		core_scsi3_lunacl_undepend_item(dest_se_deve);
3781 	if (dest_node_acl)
3782 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
3783 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3784 	core_scsi3_put_pr_reg(pr_reg);
3785 	return ret;
3786 }
3787 
3788 static unsigned long long core_scsi3_extract_reservation_key(unsigned char *cdb)
3789 {
3790 	unsigned int __v1, __v2;
3791 
3792 	__v1 = (cdb[0] << 24) | (cdb[1] << 16) | (cdb[2] << 8) | cdb[3];
3793 	__v2 = (cdb[4] << 24) | (cdb[5] << 16) | (cdb[6] << 8) | cdb[7];
3794 
3795 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
3796 }
3797 
3798 /*
3799  * See spc4r17 section 6.14 Table 170
3800  */
3801 int target_scsi3_emulate_pr_out(struct se_task *task)
3802 {
3803 	struct se_cmd *cmd = task->task_se_cmd;
3804 	unsigned char *cdb = &cmd->t_task_cdb[0];
3805 	unsigned char *buf;
3806 	u64 res_key, sa_res_key;
3807 	int sa, scope, type, aptpl;
3808 	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3809 	int ret;
3810 
3811 	/*
3812 	 * Following spc2r20 5.5.1 Reservations overview:
3813 	 *
3814 	 * If a logical unit has been reserved by any RESERVE command and is
3815 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3816 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
3817 	 * initiator or service action and shall terminate with a RESERVATION
3818 	 * CONFLICT status.
3819 	 */
3820 	if (cmd->se_dev->dev_flags & DF_SPC2_RESERVATIONS) {
3821 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3822 			" SPC-2 reservation is held, returning"
3823 			" RESERVATION_CONFLICT\n");
3824 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3825 		ret = EINVAL;
3826 		goto out;
3827 	}
3828 
3829 	/*
3830 	 * FIXME: A NULL struct se_session pointer means an this is not coming from
3831 	 * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3832 	 */
3833 	if (!cmd->se_sess) {
3834 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3835 		return -EINVAL;
3836 	}
3837 
3838 	if (cmd->data_length < 24) {
3839 		pr_warn("SPC-PR: Received PR OUT parameter list"
3840 			" length too small: %u\n", cmd->data_length);
3841 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3842 		ret = -EINVAL;
3843 		goto out;
3844 	}
3845 	/*
3846 	 * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3847 	 */
3848 	sa = (cdb[1] & 0x1f);
3849 	scope = (cdb[2] & 0xf0);
3850 	type = (cdb[2] & 0x0f);
3851 
3852 	buf = transport_kmap_data_sg(cmd);
3853 	/*
3854 	 * From PERSISTENT_RESERVE_OUT parameter list (payload)
3855 	 */
3856 	res_key = core_scsi3_extract_reservation_key(&buf[0]);
3857 	sa_res_key = core_scsi3_extract_reservation_key(&buf[8]);
3858 	/*
3859 	 * REGISTER_AND_MOVE uses a different SA parameter list containing
3860 	 * SCSI TransportIDs.
3861 	 */
3862 	if (sa != PRO_REGISTER_AND_MOVE) {
3863 		spec_i_pt = (buf[20] & 0x08);
3864 		all_tg_pt = (buf[20] & 0x04);
3865 		aptpl = (buf[20] & 0x01);
3866 	} else {
3867 		aptpl = (buf[17] & 0x01);
3868 		unreg = (buf[17] & 0x02);
3869 	}
3870 	transport_kunmap_data_sg(cmd);
3871 	buf = NULL;
3872 
3873 	/*
3874 	 * SPEC_I_PT=1 is only valid for Service action: REGISTER
3875 	 */
3876 	if (spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER)) {
3877 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3878 		ret = -EINVAL;
3879 		goto out;
3880 	}
3881 
3882 	/*
3883 	 * From spc4r17 section 6.14:
3884 	 *
3885 	 * If the SPEC_I_PT bit is set to zero, the service action is not
3886 	 * REGISTER AND MOVE, and the parameter list length is not 24, then
3887 	 * the command shall be terminated with CHECK CONDITION status, with
3888 	 * the sense key set to ILLEGAL REQUEST, and the additional sense
3889 	 * code set to PARAMETER LIST LENGTH ERROR.
3890 	 */
3891 	if (!spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER_AND_MOVE) &&
3892 	    (cmd->data_length != 24)) {
3893 		pr_warn("SPC-PR: Received PR OUT illegal parameter"
3894 			" list length: %u\n", cmd->data_length);
3895 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3896 		ret = -EINVAL;
3897 		goto out;
3898 	}
3899 	/*
3900 	 * (core_scsi3_emulate_pro_* function parameters
3901 	 * are defined by spc4r17 Table 174:
3902 	 * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3903 	 */
3904 	switch (sa) {
3905 	case PRO_REGISTER:
3906 		ret = core_scsi3_emulate_pro_register(cmd,
3907 			res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, 0);
3908 		break;
3909 	case PRO_RESERVE:
3910 		ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3911 		break;
3912 	case PRO_RELEASE:
3913 		ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3914 		break;
3915 	case PRO_CLEAR:
3916 		ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3917 		break;
3918 	case PRO_PREEMPT:
3919 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3920 					res_key, sa_res_key, 0);
3921 		break;
3922 	case PRO_PREEMPT_AND_ABORT:
3923 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3924 					res_key, sa_res_key, 1);
3925 		break;
3926 	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3927 		ret = core_scsi3_emulate_pro_register(cmd,
3928 			0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, 1);
3929 		break;
3930 	case PRO_REGISTER_AND_MOVE:
3931 		ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3932 				sa_res_key, aptpl, unreg);
3933 		break;
3934 	default:
3935 		pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3936 			" action: 0x%02x\n", cdb[1] & 0x1f);
3937 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3938 		ret = -EINVAL;
3939 		break;
3940 	}
3941 
3942 out:
3943 	if (!ret) {
3944 		task->task_scsi_status = GOOD;
3945 		transport_complete_task(task, 1);
3946 	}
3947 	return ret;
3948 }
3949 
3950 /*
3951  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3952  *
3953  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3954  */
3955 static int core_scsi3_pri_read_keys(struct se_cmd *cmd)
3956 {
3957 	struct se_device *se_dev = cmd->se_dev;
3958 	struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
3959 	struct t10_pr_registration *pr_reg;
3960 	unsigned char *buf;
3961 	u32 add_len = 0, off = 8;
3962 
3963 	if (cmd->data_length < 8) {
3964 		pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3965 			" too small\n", cmd->data_length);
3966 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3967 		return -EINVAL;
3968 	}
3969 
3970 	buf = transport_kmap_data_sg(cmd);
3971 	buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
3972 	buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
3973 	buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
3974 	buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
3975 
3976 	spin_lock(&su_dev->t10_pr.registration_lock);
3977 	list_for_each_entry(pr_reg, &su_dev->t10_pr.registration_list,
3978 			pr_reg_list) {
3979 		/*
3980 		 * Check for overflow of 8byte PRI READ_KEYS payload and
3981 		 * next reservation key list descriptor.
3982 		 */
3983 		if ((add_len + 8) > (cmd->data_length - 8))
3984 			break;
3985 
3986 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3987 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3988 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3989 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3990 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3991 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3992 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3993 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3994 
3995 		add_len += 8;
3996 	}
3997 	spin_unlock(&su_dev->t10_pr.registration_lock);
3998 
3999 	buf[4] = ((add_len >> 24) & 0xff);
4000 	buf[5] = ((add_len >> 16) & 0xff);
4001 	buf[6] = ((add_len >> 8) & 0xff);
4002 	buf[7] = (add_len & 0xff);
4003 
4004 	transport_kunmap_data_sg(cmd);
4005 
4006 	return 0;
4007 }
4008 
4009 /*
4010  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
4011  *
4012  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
4013  */
4014 static int core_scsi3_pri_read_reservation(struct se_cmd *cmd)
4015 {
4016 	struct se_device *se_dev = cmd->se_dev;
4017 	struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
4018 	struct t10_pr_registration *pr_reg;
4019 	unsigned char *buf;
4020 	u64 pr_res_key;
4021 	u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
4022 
4023 	if (cmd->data_length < 8) {
4024 		pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
4025 			" too small\n", cmd->data_length);
4026 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4027 		return -EINVAL;
4028 	}
4029 
4030 	buf = transport_kmap_data_sg(cmd);
4031 	buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
4032 	buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
4033 	buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
4034 	buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
4035 
4036 	spin_lock(&se_dev->dev_reservation_lock);
4037 	pr_reg = se_dev->dev_pr_res_holder;
4038 	if ((pr_reg)) {
4039 		/*
4040 		 * Set the hardcoded Additional Length
4041 		 */
4042 		buf[4] = ((add_len >> 24) & 0xff);
4043 		buf[5] = ((add_len >> 16) & 0xff);
4044 		buf[6] = ((add_len >> 8) & 0xff);
4045 		buf[7] = (add_len & 0xff);
4046 
4047 		if (cmd->data_length < 22)
4048 			goto err;
4049 
4050 		/*
4051 		 * Set the Reservation key.
4052 		 *
4053 		 * From spc4r17, section 5.7.10:
4054 		 * A persistent reservation holder has its reservation key
4055 		 * returned in the parameter data from a PERSISTENT
4056 		 * RESERVE IN command with READ RESERVATION service action as
4057 		 * follows:
4058 		 * a) For a persistent reservation of the type Write Exclusive
4059 		 *    - All Registrants or Exclusive Access ­ All Regitrants,
4060 		 *      the reservation key shall be set to zero; or
4061 		 * b) For all other persistent reservation types, the
4062 		 *    reservation key shall be set to the registered
4063 		 *    reservation key for the I_T nexus that holds the
4064 		 *    persistent reservation.
4065 		 */
4066 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
4067 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
4068 			pr_res_key = 0;
4069 		else
4070 			pr_res_key = pr_reg->pr_res_key;
4071 
4072 		buf[8] = ((pr_res_key >> 56) & 0xff);
4073 		buf[9] = ((pr_res_key >> 48) & 0xff);
4074 		buf[10] = ((pr_res_key >> 40) & 0xff);
4075 		buf[11] = ((pr_res_key >> 32) & 0xff);
4076 		buf[12] = ((pr_res_key >> 24) & 0xff);
4077 		buf[13] = ((pr_res_key >> 16) & 0xff);
4078 		buf[14] = ((pr_res_key >> 8) & 0xff);
4079 		buf[15] = (pr_res_key & 0xff);
4080 		/*
4081 		 * Set the SCOPE and TYPE
4082 		 */
4083 		buf[21] = (pr_reg->pr_res_scope & 0xf0) |
4084 			  (pr_reg->pr_res_type & 0x0f);
4085 	}
4086 
4087 err:
4088 	spin_unlock(&se_dev->dev_reservation_lock);
4089 	transport_kunmap_data_sg(cmd);
4090 
4091 	return 0;
4092 }
4093 
4094 /*
4095  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
4096  *
4097  * See spc4r17 section 6.13.4 Table 165
4098  */
4099 static int core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
4100 {
4101 	struct se_device *dev = cmd->se_dev;
4102 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
4103 	unsigned char *buf;
4104 	u16 add_len = 8; /* Hardcoded to 8. */
4105 
4106 	if (cmd->data_length < 6) {
4107 		pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
4108 			" %u too small\n", cmd->data_length);
4109 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4110 		return -EINVAL;
4111 	}
4112 
4113 	buf = transport_kmap_data_sg(cmd);
4114 
4115 	buf[0] = ((add_len << 8) & 0xff);
4116 	buf[1] = (add_len & 0xff);
4117 	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
4118 	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
4119 	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
4120 	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
4121 	/*
4122 	 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
4123 	 * set the TMV: Task Mask Valid bit.
4124 	 */
4125 	buf[3] |= 0x80;
4126 	/*
4127 	 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
4128 	 */
4129 	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
4130 	/*
4131 	 * PTPL_A: Persistence across Target Power Loss Active bit
4132 	 */
4133 	if (pr_tmpl->pr_aptpl_active)
4134 		buf[3] |= 0x01;
4135 	/*
4136 	 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
4137 	 */
4138 	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
4139 	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
4140 	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
4141 	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
4142 	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
4143 	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
4144 
4145 	transport_kunmap_data_sg(cmd);
4146 
4147 	return 0;
4148 }
4149 
4150 /*
4151  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
4152  *
4153  * See spc4r17 section 6.13.5 Table 168 and 169
4154  */
4155 static int core_scsi3_pri_read_full_status(struct se_cmd *cmd)
4156 {
4157 	struct se_device *se_dev = cmd->se_dev;
4158 	struct se_node_acl *se_nacl;
4159 	struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
4160 	struct se_portal_group *se_tpg;
4161 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
4162 	struct t10_reservation *pr_tmpl = &se_dev->se_sub_dev->t10_pr;
4163 	unsigned char *buf;
4164 	u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
4165 	u32 off = 8; /* off into first Full Status descriptor */
4166 	int format_code = 0;
4167 
4168 	if (cmd->data_length < 8) {
4169 		pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
4170 			" too small\n", cmd->data_length);
4171 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4172 		return -EINVAL;
4173 	}
4174 
4175 	buf = transport_kmap_data_sg(cmd);
4176 
4177 	buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
4178 	buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
4179 	buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
4180 	buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
4181 
4182 	spin_lock(&pr_tmpl->registration_lock);
4183 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
4184 			&pr_tmpl->registration_list, pr_reg_list) {
4185 
4186 		se_nacl = pr_reg->pr_reg_nacl;
4187 		se_tpg = pr_reg->pr_reg_nacl->se_tpg;
4188 		add_desc_len = 0;
4189 
4190 		atomic_inc(&pr_reg->pr_res_holders);
4191 		smp_mb__after_atomic_inc();
4192 		spin_unlock(&pr_tmpl->registration_lock);
4193 		/*
4194 		 * Determine expected length of $FABRIC_MOD specific
4195 		 * TransportID full status descriptor..
4196 		 */
4197 		exp_desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id_len(
4198 				se_tpg, se_nacl, pr_reg, &format_code);
4199 
4200 		if ((exp_desc_len + add_len) > cmd->data_length) {
4201 			pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
4202 				" out of buffer: %d\n", cmd->data_length);
4203 			spin_lock(&pr_tmpl->registration_lock);
4204 			atomic_dec(&pr_reg->pr_res_holders);
4205 			smp_mb__after_atomic_dec();
4206 			break;
4207 		}
4208 		/*
4209 		 * Set RESERVATION KEY
4210 		 */
4211 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
4212 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
4213 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
4214 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
4215 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
4216 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
4217 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
4218 		buf[off++] = (pr_reg->pr_res_key & 0xff);
4219 		off += 4; /* Skip Over Reserved area */
4220 
4221 		/*
4222 		 * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
4223 		 */
4224 		if (pr_reg->pr_reg_all_tg_pt)
4225 			buf[off] = 0x02;
4226 		/*
4227 		 * The struct se_lun pointer will be present for the
4228 		 * reservation holder for PR_HOLDER bit.
4229 		 *
4230 		 * Also, if this registration is the reservation
4231 		 * holder, fill in SCOPE and TYPE in the next byte.
4232 		 */
4233 		if (pr_reg->pr_res_holder) {
4234 			buf[off++] |= 0x01;
4235 			buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
4236 				     (pr_reg->pr_res_type & 0x0f);
4237 		} else
4238 			off += 2;
4239 
4240 		off += 4; /* Skip over reserved area */
4241 		/*
4242 		 * From spc4r17 6.3.15:
4243 		 *
4244 		 * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
4245 		 * IDENTIFIER field contains the relative port identifier (see
4246 		 * 3.1.120) of the target port that is part of the I_T nexus
4247 		 * described by this full status descriptor. If the ALL_TG_PT
4248 		 * bit is set to one, the contents of the RELATIVE TARGET PORT
4249 		 * IDENTIFIER field are not defined by this standard.
4250 		 */
4251 		if (!pr_reg->pr_reg_all_tg_pt) {
4252 			struct se_port *port = pr_reg->pr_reg_tg_pt_lun->lun_sep;
4253 
4254 			buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
4255 			buf[off++] = (port->sep_rtpi & 0xff);
4256 		} else
4257 			off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFER */
4258 
4259 		/*
4260 		 * Now, have the $FABRIC_MOD fill in the protocol identifier
4261 		 */
4262 		desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id(se_tpg,
4263 				se_nacl, pr_reg, &format_code, &buf[off+4]);
4264 
4265 		spin_lock(&pr_tmpl->registration_lock);
4266 		atomic_dec(&pr_reg->pr_res_holders);
4267 		smp_mb__after_atomic_dec();
4268 		/*
4269 		 * Set the ADDITIONAL DESCRIPTOR LENGTH
4270 		 */
4271 		buf[off++] = ((desc_len >> 24) & 0xff);
4272 		buf[off++] = ((desc_len >> 16) & 0xff);
4273 		buf[off++] = ((desc_len >> 8) & 0xff);
4274 		buf[off++] = (desc_len & 0xff);
4275 		/*
4276 		 * Size of full desctipor header minus TransportID
4277 		 * containing $FABRIC_MOD specific) initiator device/port
4278 		 * WWN information.
4279 		 *
4280 		 *  See spc4r17 Section 6.13.5 Table 169
4281 		 */
4282 		add_desc_len = (24 + desc_len);
4283 
4284 		off += desc_len;
4285 		add_len += add_desc_len;
4286 	}
4287 	spin_unlock(&pr_tmpl->registration_lock);
4288 	/*
4289 	 * Set ADDITIONAL_LENGTH
4290 	 */
4291 	buf[4] = ((add_len >> 24) & 0xff);
4292 	buf[5] = ((add_len >> 16) & 0xff);
4293 	buf[6] = ((add_len >> 8) & 0xff);
4294 	buf[7] = (add_len & 0xff);
4295 
4296 	transport_kunmap_data_sg(cmd);
4297 
4298 	return 0;
4299 }
4300 
4301 int target_scsi3_emulate_pr_in(struct se_task *task)
4302 {
4303 	struct se_cmd *cmd = task->task_se_cmd;
4304 	int ret;
4305 
4306 	/*
4307 	 * Following spc2r20 5.5.1 Reservations overview:
4308 	 *
4309 	 * If a logical unit has been reserved by any RESERVE command and is
4310 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4311 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
4312 	 * initiator or service action and shall terminate with a RESERVATION
4313 	 * CONFLICT status.
4314 	 */
4315 	if (cmd->se_dev->dev_flags & DF_SPC2_RESERVATIONS) {
4316 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4317 			" SPC-2 reservation is held, returning"
4318 			" RESERVATION_CONFLICT\n");
4319 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
4320 		return -EINVAL;
4321 	}
4322 
4323 	switch (cmd->t_task_cdb[1] & 0x1f) {
4324 	case PRI_READ_KEYS:
4325 		ret = core_scsi3_pri_read_keys(cmd);
4326 		break;
4327 	case PRI_READ_RESERVATION:
4328 		ret = core_scsi3_pri_read_reservation(cmd);
4329 		break;
4330 	case PRI_REPORT_CAPABILITIES:
4331 		ret = core_scsi3_pri_report_capabilities(cmd);
4332 		break;
4333 	case PRI_READ_FULL_STATUS:
4334 		ret = core_scsi3_pri_read_full_status(cmd);
4335 		break;
4336 	default:
4337 		pr_err("Unknown PERSISTENT_RESERVE_IN service"
4338 			" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4339 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4340 		ret = -EINVAL;
4341 		break;
4342 	}
4343 
4344 	if (!ret) {
4345 		task->task_scsi_status = GOOD;
4346 		transport_complete_task(task, 1);
4347 	}
4348 	return ret;
4349 }
4350 
4351 static int core_pt_reservation_check(struct se_cmd *cmd, u32 *pr_res_type)
4352 {
4353 	return 0;
4354 }
4355 
4356 static int core_pt_seq_non_holder(
4357 	struct se_cmd *cmd,
4358 	unsigned char *cdb,
4359 	u32 pr_reg_type)
4360 {
4361 	return 0;
4362 }
4363 
4364 int core_setup_reservations(struct se_device *dev, int force_pt)
4365 {
4366 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
4367 	struct t10_reservation *rest = &su_dev->t10_pr;
4368 	/*
4369 	 * If this device is from Target_Core_Mod/pSCSI, use the reservations
4370 	 * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
4371 	 * cause a problem because libata and some SATA RAID HBAs appear
4372 	 * under Linux/SCSI, but to emulate reservations themselves.
4373 	 */
4374 	if (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
4375 	    !(dev->se_sub_dev->se_dev_attrib.emulate_reservations)) || force_pt) {
4376 		rest->res_type = SPC_PASSTHROUGH;
4377 		rest->pr_ops.t10_reservation_check = &core_pt_reservation_check;
4378 		rest->pr_ops.t10_seq_non_holder = &core_pt_seq_non_holder;
4379 		pr_debug("%s: Using SPC_PASSTHROUGH, no reservation"
4380 			" emulation\n", dev->transport->name);
4381 		return 0;
4382 	}
4383 	/*
4384 	 * If SPC-3 or above is reported by real or emulated struct se_device,
4385 	 * use emulated Persistent Reservations.
4386 	 */
4387 	if (dev->transport->get_device_rev(dev) >= SCSI_3) {
4388 		rest->res_type = SPC3_PERSISTENT_RESERVATIONS;
4389 		rest->pr_ops.t10_reservation_check = &core_scsi3_pr_reservation_check;
4390 		rest->pr_ops.t10_seq_non_holder = &core_scsi3_pr_seq_non_holder;
4391 		pr_debug("%s: Using SPC3_PERSISTENT_RESERVATIONS"
4392 			" emulation\n", dev->transport->name);
4393 	} else {
4394 		rest->res_type = SPC2_RESERVATIONS;
4395 		rest->pr_ops.t10_reservation_check = &core_scsi2_reservation_check;
4396 		rest->pr_ops.t10_seq_non_holder =
4397 				&core_scsi2_reservation_seq_non_holder;
4398 		pr_debug("%s: Using SPC2_RESERVATIONS emulation\n",
4399 			dev->transport->name);
4400 	}
4401 
4402 	return 0;
4403 }
4404