xref: /linux/drivers/target/target_core_pr.c (revision e35fa8c2d0feb977c2f7d14a973b4132483ffef3)
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 	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 
1502 	local_se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
1503 	/*
1504 	 * Allocate a struct pr_transport_id_holder and setup the
1505 	 * local_node_acl and local_se_deve pointers and add to
1506 	 * struct list_head tid_dest_list for add registration
1507 	 * processing in the loop of tid_dest_list below.
1508 	 */
1509 	tidh_new = kzalloc(sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1510 	if (!tidh_new) {
1511 		pr_err("Unable to allocate tidh_new\n");
1512 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1513 		return -EINVAL;
1514 	}
1515 	INIT_LIST_HEAD(&tidh_new->dest_list);
1516 	tidh_new->dest_tpg = tpg;
1517 	tidh_new->dest_node_acl = se_sess->se_node_acl;
1518 	tidh_new->dest_se_deve = local_se_deve;
1519 
1520 	local_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1521 				se_sess->se_node_acl, local_se_deve, l_isid,
1522 				sa_res_key, all_tg_pt, aptpl);
1523 	if (!local_pr_reg) {
1524 		kfree(tidh_new);
1525 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1526 		return -ENOMEM;
1527 	}
1528 	tidh_new->dest_pr_reg = local_pr_reg;
1529 	/*
1530 	 * The local I_T nexus does not hold any configfs dependances,
1531 	 * so we set tid_h->dest_local_nexus=1 to prevent the
1532 	 * configfs_undepend_item() calls in the tid_dest_list loops below.
1533 	 */
1534 	tidh_new->dest_local_nexus = 1;
1535 	list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1536 
1537 	buf = transport_kmap_data_sg(cmd);
1538 	/*
1539 	 * For a PERSISTENT RESERVE OUT specify initiator ports payload,
1540 	 * first extract TransportID Parameter Data Length, and make sure
1541 	 * the value matches up to the SCSI expected data transfer length.
1542 	 */
1543 	tpdl = (buf[24] & 0xff) << 24;
1544 	tpdl |= (buf[25] & 0xff) << 16;
1545 	tpdl |= (buf[26] & 0xff) << 8;
1546 	tpdl |= buf[27] & 0xff;
1547 
1548 	if ((tpdl + 28) != cmd->data_length) {
1549 		pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1550 			" does not equal CDB data_length: %u\n", tpdl,
1551 			cmd->data_length);
1552 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1553 		ret = -EINVAL;
1554 		goto out;
1555 	}
1556 	/*
1557 	 * Start processing the received transport IDs using the
1558 	 * receiving I_T Nexus portal's fabric dependent methods to
1559 	 * obtain the SCSI Initiator Port/Device Identifiers.
1560 	 */
1561 	ptr = &buf[28];
1562 
1563 	while (tpdl > 0) {
1564 		proto_ident = (ptr[0] & 0x0f);
1565 		dest_tpg = NULL;
1566 
1567 		spin_lock(&dev->se_port_lock);
1568 		list_for_each_entry(tmp_port, &dev->dev_sep_list, sep_list) {
1569 			tmp_tpg = tmp_port->sep_tpg;
1570 			if (!tmp_tpg)
1571 				continue;
1572 			tmp_tf_ops = tmp_tpg->se_tpg_tfo;
1573 			if (!tmp_tf_ops)
1574 				continue;
1575 			if (!tmp_tf_ops->get_fabric_proto_ident ||
1576 			    !tmp_tf_ops->tpg_parse_pr_out_transport_id)
1577 				continue;
1578 			/*
1579 			 * Look for the matching proto_ident provided by
1580 			 * the received TransportID
1581 			 */
1582 			tmp_proto_ident = tmp_tf_ops->get_fabric_proto_ident(tmp_tpg);
1583 			if (tmp_proto_ident != proto_ident)
1584 				continue;
1585 			dest_rtpi = tmp_port->sep_rtpi;
1586 
1587 			i_str = tmp_tf_ops->tpg_parse_pr_out_transport_id(
1588 					tmp_tpg, (const char *)ptr, &tid_len,
1589 					&iport_ptr);
1590 			if (!i_str)
1591 				continue;
1592 
1593 			atomic_inc(&tmp_tpg->tpg_pr_ref_count);
1594 			smp_mb__after_atomic_inc();
1595 			spin_unlock(&dev->se_port_lock);
1596 
1597 			ret = core_scsi3_tpg_depend_item(tmp_tpg);
1598 			if (ret != 0) {
1599 				pr_err(" core_scsi3_tpg_depend_item()"
1600 					" for tmp_tpg\n");
1601 				atomic_dec(&tmp_tpg->tpg_pr_ref_count);
1602 				smp_mb__after_atomic_dec();
1603 				cmd->scsi_sense_reason =
1604 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1605 				ret = -EINVAL;
1606 				goto out;
1607 			}
1608 			/*
1609 			 * Locate the desination initiator ACL to be registered
1610 			 * from the decoded fabric module specific TransportID
1611 			 * at *i_str.
1612 			 */
1613 			spin_lock_irq(&tmp_tpg->acl_node_lock);
1614 			dest_node_acl = __core_tpg_get_initiator_node_acl(
1615 						tmp_tpg, i_str);
1616 			if (dest_node_acl) {
1617 				atomic_inc(&dest_node_acl->acl_pr_ref_count);
1618 				smp_mb__after_atomic_inc();
1619 			}
1620 			spin_unlock_irq(&tmp_tpg->acl_node_lock);
1621 
1622 			if (!dest_node_acl) {
1623 				core_scsi3_tpg_undepend_item(tmp_tpg);
1624 				spin_lock(&dev->se_port_lock);
1625 				continue;
1626 			}
1627 
1628 			ret = core_scsi3_nodeacl_depend_item(dest_node_acl);
1629 			if (ret != 0) {
1630 				pr_err("configfs_depend_item() failed"
1631 					" for dest_node_acl->acl_group\n");
1632 				atomic_dec(&dest_node_acl->acl_pr_ref_count);
1633 				smp_mb__after_atomic_dec();
1634 				core_scsi3_tpg_undepend_item(tmp_tpg);
1635 				cmd->scsi_sense_reason =
1636 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1637 				ret = -EINVAL;
1638 				goto out;
1639 			}
1640 
1641 			dest_tpg = tmp_tpg;
1642 			pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node:"
1643 				" %s Port RTPI: %hu\n",
1644 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1645 				dest_node_acl->initiatorname, dest_rtpi);
1646 
1647 			spin_lock(&dev->se_port_lock);
1648 			break;
1649 		}
1650 		spin_unlock(&dev->se_port_lock);
1651 
1652 		if (!dest_tpg) {
1653 			pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1654 					" dest_tpg\n");
1655 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1656 			ret = -EINVAL;
1657 			goto out;
1658 		}
1659 #if 0
1660 		pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1661 			" tid_len: %d for %s + %s\n",
1662 			dest_tpg->se_tpg_tfo->get_fabric_name(), cmd->data_length,
1663 			tpdl, tid_len, i_str, iport_ptr);
1664 #endif
1665 		if (tid_len > tpdl) {
1666 			pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1667 				" %u for Transport ID: %s\n", tid_len, ptr);
1668 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1669 			core_scsi3_tpg_undepend_item(dest_tpg);
1670 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1671 			ret = -EINVAL;
1672 			goto out;
1673 		}
1674 		/*
1675 		 * Locate the desintation struct se_dev_entry pointer for matching
1676 		 * RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1677 		 * Target Port.
1678 		 */
1679 		dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1680 					dest_rtpi);
1681 		if (!dest_se_deve) {
1682 			pr_err("Unable to locate %s dest_se_deve"
1683 				" from destination RTPI: %hu\n",
1684 				dest_tpg->se_tpg_tfo->get_fabric_name(),
1685 				dest_rtpi);
1686 
1687 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1688 			core_scsi3_tpg_undepend_item(dest_tpg);
1689 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1690 			ret = -EINVAL;
1691 			goto out;
1692 		}
1693 
1694 		ret = core_scsi3_lunacl_depend_item(dest_se_deve);
1695 		if (ret < 0) {
1696 			pr_err("core_scsi3_lunacl_depend_item()"
1697 					" failed\n");
1698 			atomic_dec(&dest_se_deve->pr_ref_count);
1699 			smp_mb__after_atomic_dec();
1700 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1701 			core_scsi3_tpg_undepend_item(dest_tpg);
1702 			cmd->scsi_sense_reason =
1703 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1704 			ret = -EINVAL;
1705 			goto out;
1706 		}
1707 #if 0
1708 		pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1709 			" dest_se_deve mapped_lun: %u\n",
1710 			dest_tpg->se_tpg_tfo->get_fabric_name(),
1711 			dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1712 #endif
1713 		/*
1714 		 * Skip any TransportIDs that already have a registration for
1715 		 * this target port.
1716 		 */
1717 		pr_reg_e = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
1718 					iport_ptr);
1719 		if (pr_reg_e) {
1720 			core_scsi3_put_pr_reg(pr_reg_e);
1721 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1722 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1723 			core_scsi3_tpg_undepend_item(dest_tpg);
1724 			ptr += tid_len;
1725 			tpdl -= tid_len;
1726 			tid_len = 0;
1727 			continue;
1728 		}
1729 		/*
1730 		 * Allocate a struct pr_transport_id_holder and setup
1731 		 * the dest_node_acl and dest_se_deve pointers for the
1732 		 * loop below.
1733 		 */
1734 		tidh_new = kzalloc(sizeof(struct pr_transport_id_holder),
1735 				GFP_KERNEL);
1736 		if (!tidh_new) {
1737 			pr_err("Unable to allocate tidh_new\n");
1738 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1739 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1740 			core_scsi3_tpg_undepend_item(dest_tpg);
1741 			cmd->scsi_sense_reason =
1742 				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1743 			ret = -ENOMEM;
1744 			goto out;
1745 		}
1746 		INIT_LIST_HEAD(&tidh_new->dest_list);
1747 		tidh_new->dest_tpg = dest_tpg;
1748 		tidh_new->dest_node_acl = dest_node_acl;
1749 		tidh_new->dest_se_deve = dest_se_deve;
1750 
1751 		/*
1752 		 * Allocate, but do NOT add the registration for the
1753 		 * TransportID referenced SCSI Initiator port.  This
1754 		 * done because of the following from spc4r17 in section
1755 		 * 6.14.3 wrt SPEC_I_PT:
1756 		 *
1757 		 * "If a registration fails for any initiator port (e.g., if th
1758 		 * logical unit does not have enough resources available to
1759 		 * hold the registration information), no registrations shall be
1760 		 * made, and the command shall be terminated with
1761 		 * CHECK CONDITION status."
1762 		 *
1763 		 * That means we call __core_scsi3_alloc_registration() here,
1764 		 * and then call __core_scsi3_add_registration() in the
1765 		 * 2nd loop which will never fail.
1766 		 */
1767 		dest_pr_reg = __core_scsi3_alloc_registration(cmd->se_dev,
1768 				dest_node_acl, dest_se_deve, iport_ptr,
1769 				sa_res_key, all_tg_pt, aptpl);
1770 		if (!dest_pr_reg) {
1771 			core_scsi3_lunacl_undepend_item(dest_se_deve);
1772 			core_scsi3_nodeacl_undepend_item(dest_node_acl);
1773 			core_scsi3_tpg_undepend_item(dest_tpg);
1774 			kfree(tidh_new);
1775 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
1776 			ret = -EINVAL;
1777 			goto out;
1778 		}
1779 		tidh_new->dest_pr_reg = dest_pr_reg;
1780 		list_add_tail(&tidh_new->dest_list, &tid_dest_list);
1781 
1782 		ptr += tid_len;
1783 		tpdl -= tid_len;
1784 		tid_len = 0;
1785 
1786 	}
1787 
1788 	transport_kunmap_data_sg(cmd);
1789 
1790 	/*
1791 	 * Go ahead and create a registrations from tid_dest_list for the
1792 	 * SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1793 	 * and dest_se_deve.
1794 	 *
1795 	 * The SA Reservation Key from the PROUT is set for the
1796 	 * registration, and ALL_TG_PT is also passed.  ALL_TG_PT=1
1797 	 * means that the TransportID Initiator port will be
1798 	 * registered on all of the target ports in the SCSI target device
1799 	 * ALL_TG_PT=0 means the registration will only be for the
1800 	 * SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1801 	 * was received.
1802 	 */
1803 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1804 		dest_tpg = tidh->dest_tpg;
1805 		dest_node_acl = tidh->dest_node_acl;
1806 		dest_se_deve = tidh->dest_se_deve;
1807 		dest_pr_reg = tidh->dest_pr_reg;
1808 		dest_local_nexus = tidh->dest_local_nexus;
1809 
1810 		list_del(&tidh->dest_list);
1811 		kfree(tidh);
1812 
1813 		memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1814 		prf_isid = core_pr_dump_initiator_port(dest_pr_reg, &i_buf[0],
1815 						PR_REG_ISID_ID_LEN);
1816 
1817 		__core_scsi3_add_registration(cmd->se_dev, dest_node_acl,
1818 					dest_pr_reg, 0, 0);
1819 
1820 		pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1821 			" registered Transport ID for Node: %s%s Mapped LUN:"
1822 			" %u\n", dest_tpg->se_tpg_tfo->get_fabric_name(),
1823 			dest_node_acl->initiatorname, (prf_isid) ?
1824 			&i_buf[0] : "", dest_se_deve->mapped_lun);
1825 
1826 		if (dest_local_nexus)
1827 			continue;
1828 
1829 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1830 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1831 		core_scsi3_tpg_undepend_item(dest_tpg);
1832 	}
1833 
1834 	return 0;
1835 out:
1836 	transport_kunmap_data_sg(cmd);
1837 	/*
1838 	 * For the failure case, release everything from tid_dest_list
1839 	 * including *dest_pr_reg and the configfs dependances..
1840 	 */
1841 	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1842 		dest_tpg = tidh->dest_tpg;
1843 		dest_node_acl = tidh->dest_node_acl;
1844 		dest_se_deve = tidh->dest_se_deve;
1845 		dest_pr_reg = tidh->dest_pr_reg;
1846 		dest_local_nexus = tidh->dest_local_nexus;
1847 
1848 		list_del(&tidh->dest_list);
1849 		kfree(tidh);
1850 		/*
1851 		 * Release any extra ALL_TG_PT=1 registrations for
1852 		 * the SPEC_I_PT=1 case.
1853 		 */
1854 		list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1855 				&dest_pr_reg->pr_reg_atp_list,
1856 				pr_reg_atp_mem_list) {
1857 			list_del(&pr_reg_tmp->pr_reg_atp_mem_list);
1858 			core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
1859 			kmem_cache_free(t10_pr_reg_cache, pr_reg_tmp);
1860 		}
1861 
1862 		kfree(dest_pr_reg->pr_aptpl_buf);
1863 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
1864 
1865 		if (dest_local_nexus)
1866 			continue;
1867 
1868 		core_scsi3_lunacl_undepend_item(dest_se_deve);
1869 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
1870 		core_scsi3_tpg_undepend_item(dest_tpg);
1871 	}
1872 	return ret;
1873 }
1874 
1875 /*
1876  * Called with struct se_device->dev_reservation_lock held
1877  */
1878 static int __core_scsi3_update_aptpl_buf(
1879 	struct se_device *dev,
1880 	unsigned char *buf,
1881 	u32 pr_aptpl_buf_len,
1882 	int clear_aptpl_metadata)
1883 {
1884 	struct se_lun *lun;
1885 	struct se_portal_group *tpg;
1886 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1887 	struct t10_pr_registration *pr_reg;
1888 	unsigned char tmp[512], isid_buf[32];
1889 	ssize_t len = 0;
1890 	int reg_count = 0;
1891 
1892 	memset(buf, 0, pr_aptpl_buf_len);
1893 	/*
1894 	 * Called to clear metadata once APTPL has been deactivated.
1895 	 */
1896 	if (clear_aptpl_metadata) {
1897 		snprintf(buf, pr_aptpl_buf_len,
1898 				"No Registrations or Reservations\n");
1899 		return 0;
1900 	}
1901 	/*
1902 	 * Walk the registration list..
1903 	 */
1904 	spin_lock(&su_dev->t10_pr.registration_lock);
1905 	list_for_each_entry(pr_reg, &su_dev->t10_pr.registration_list,
1906 			pr_reg_list) {
1907 
1908 		tmp[0] = '\0';
1909 		isid_buf[0] = '\0';
1910 		tpg = pr_reg->pr_reg_nacl->se_tpg;
1911 		lun = pr_reg->pr_reg_tg_pt_lun;
1912 		/*
1913 		 * Write out any ISID value to APTPL metadata that was included
1914 		 * in the original registration.
1915 		 */
1916 		if (pr_reg->isid_present_at_reg)
1917 			snprintf(isid_buf, 32, "initiator_sid=%s\n",
1918 					pr_reg->pr_reg_isid);
1919 		/*
1920 		 * Include special metadata if the pr_reg matches the
1921 		 * reservation holder.
1922 		 */
1923 		if (dev->dev_pr_res_holder == pr_reg) {
1924 			snprintf(tmp, 512, "PR_REG_START: %d"
1925 				"\ninitiator_fabric=%s\n"
1926 				"initiator_node=%s\n%s"
1927 				"sa_res_key=%llu\n"
1928 				"res_holder=1\nres_type=%02x\n"
1929 				"res_scope=%02x\nres_all_tg_pt=%d\n"
1930 				"mapped_lun=%u\n", reg_count,
1931 				tpg->se_tpg_tfo->get_fabric_name(),
1932 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1933 				pr_reg->pr_res_key, pr_reg->pr_res_type,
1934 				pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1935 				pr_reg->pr_res_mapped_lun);
1936 		} else {
1937 			snprintf(tmp, 512, "PR_REG_START: %d\n"
1938 				"initiator_fabric=%s\ninitiator_node=%s\n%s"
1939 				"sa_res_key=%llu\nres_holder=0\n"
1940 				"res_all_tg_pt=%d\nmapped_lun=%u\n",
1941 				reg_count, tpg->se_tpg_tfo->get_fabric_name(),
1942 				pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1943 				pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1944 				pr_reg->pr_res_mapped_lun);
1945 		}
1946 
1947 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1948 			pr_err("Unable to update renaming"
1949 				" APTPL metadata\n");
1950 			spin_unlock(&su_dev->t10_pr.registration_lock);
1951 			return -EMSGSIZE;
1952 		}
1953 		len += sprintf(buf+len, "%s", tmp);
1954 
1955 		/*
1956 		 * Include information about the associated SCSI target port.
1957 		 */
1958 		snprintf(tmp, 512, "target_fabric=%s\ntarget_node=%s\n"
1959 			"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%u\nPR_REG_END:"
1960 			" %d\n", tpg->se_tpg_tfo->get_fabric_name(),
1961 			tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1962 			tpg->se_tpg_tfo->tpg_get_tag(tpg),
1963 			lun->lun_sep->sep_rtpi, lun->unpacked_lun, reg_count);
1964 
1965 		if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1966 			pr_err("Unable to update renaming"
1967 				" APTPL metadata\n");
1968 			spin_unlock(&su_dev->t10_pr.registration_lock);
1969 			return -EMSGSIZE;
1970 		}
1971 		len += sprintf(buf+len, "%s", tmp);
1972 		reg_count++;
1973 	}
1974 	spin_unlock(&su_dev->t10_pr.registration_lock);
1975 
1976 	if (!reg_count)
1977 		len += sprintf(buf+len, "No Registrations or Reservations");
1978 
1979 	return 0;
1980 }
1981 
1982 static int core_scsi3_update_aptpl_buf(
1983 	struct se_device *dev,
1984 	unsigned char *buf,
1985 	u32 pr_aptpl_buf_len,
1986 	int clear_aptpl_metadata)
1987 {
1988 	int ret;
1989 
1990 	spin_lock(&dev->dev_reservation_lock);
1991 	ret = __core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len,
1992 				clear_aptpl_metadata);
1993 	spin_unlock(&dev->dev_reservation_lock);
1994 
1995 	return ret;
1996 }
1997 
1998 /*
1999  * Called with struct se_device->aptpl_file_mutex held
2000  */
2001 static int __core_scsi3_write_aptpl_to_file(
2002 	struct se_device *dev,
2003 	unsigned char *buf,
2004 	u32 pr_aptpl_buf_len)
2005 {
2006 	struct t10_wwn *wwn = &dev->se_sub_dev->t10_wwn;
2007 	struct file *file;
2008 	struct iovec iov[1];
2009 	mm_segment_t old_fs;
2010 	int flags = O_RDWR | O_CREAT | O_TRUNC;
2011 	char path[512];
2012 	int ret;
2013 
2014 	memset(iov, 0, sizeof(struct iovec));
2015 	memset(path, 0, 512);
2016 
2017 	if (strlen(&wwn->unit_serial[0]) >= 512) {
2018 		pr_err("WWN value for struct se_device does not fit"
2019 			" into path buffer\n");
2020 		return -EMSGSIZE;
2021 	}
2022 
2023 	snprintf(path, 512, "/var/target/pr/aptpl_%s", &wwn->unit_serial[0]);
2024 	file = filp_open(path, flags, 0600);
2025 	if (IS_ERR(file) || !file || !file->f_dentry) {
2026 		pr_err("filp_open(%s) for APTPL metadata"
2027 			" failed\n", path);
2028 		return (PTR_ERR(file) < 0 ? PTR_ERR(file) : -ENOENT);
2029 	}
2030 
2031 	iov[0].iov_base = &buf[0];
2032 	if (!pr_aptpl_buf_len)
2033 		iov[0].iov_len = (strlen(&buf[0]) + 1); /* Add extra for NULL */
2034 	else
2035 		iov[0].iov_len = pr_aptpl_buf_len;
2036 
2037 	old_fs = get_fs();
2038 	set_fs(get_ds());
2039 	ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
2040 	set_fs(old_fs);
2041 
2042 	if (ret < 0) {
2043 		pr_debug("Error writing APTPL metadata file: %s\n", path);
2044 		filp_close(file, NULL);
2045 		return -EIO;
2046 	}
2047 	filp_close(file, NULL);
2048 
2049 	return 0;
2050 }
2051 
2052 static int core_scsi3_update_and_write_aptpl(
2053 	struct se_device *dev,
2054 	unsigned char *in_buf,
2055 	u32 in_pr_aptpl_buf_len)
2056 {
2057 	unsigned char null_buf[64], *buf;
2058 	u32 pr_aptpl_buf_len;
2059 	int ret, clear_aptpl_metadata = 0;
2060 	/*
2061 	 * Can be called with a NULL pointer from PROUT service action CLEAR
2062 	 */
2063 	if (!in_buf) {
2064 		memset(null_buf, 0, 64);
2065 		buf = &null_buf[0];
2066 		/*
2067 		 * This will clear the APTPL metadata to:
2068 		 * "No Registrations or Reservations" status
2069 		 */
2070 		pr_aptpl_buf_len = 64;
2071 		clear_aptpl_metadata = 1;
2072 	} else {
2073 		buf = in_buf;
2074 		pr_aptpl_buf_len = in_pr_aptpl_buf_len;
2075 	}
2076 
2077 	ret = core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len,
2078 				clear_aptpl_metadata);
2079 	if (ret != 0)
2080 		return ret;
2081 	/*
2082 	 * __core_scsi3_write_aptpl_to_file() will call strlen()
2083 	 * on the passed buf to determine pr_aptpl_buf_len.
2084 	 */
2085 	ret = __core_scsi3_write_aptpl_to_file(dev, buf, 0);
2086 	if (ret != 0)
2087 		return ret;
2088 
2089 	return ret;
2090 }
2091 
2092 static int core_scsi3_emulate_pro_register(
2093 	struct se_cmd *cmd,
2094 	u64 res_key,
2095 	u64 sa_res_key,
2096 	int aptpl,
2097 	int all_tg_pt,
2098 	int spec_i_pt,
2099 	int ignore_key)
2100 {
2101 	struct se_session *se_sess = cmd->se_sess;
2102 	struct se_device *dev = cmd->se_dev;
2103 	struct se_dev_entry *se_deve;
2104 	struct se_lun *se_lun = cmd->se_lun;
2105 	struct se_portal_group *se_tpg;
2106 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp, *pr_reg_e;
2107 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2108 	/* Used for APTPL metadata w/ UNREGISTER */
2109 	unsigned char *pr_aptpl_buf = NULL;
2110 	unsigned char isid_buf[PR_REG_ISID_LEN], *isid_ptr = NULL;
2111 	int pr_holder = 0, ret = 0, type;
2112 
2113 	if (!se_sess || !se_lun) {
2114 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2115 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2116 		return -EINVAL;
2117 	}
2118 	se_tpg = se_sess->se_tpg;
2119 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2120 
2121 	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2122 		memset(&isid_buf[0], 0, PR_REG_ISID_LEN);
2123 		se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2124 				PR_REG_ISID_LEN);
2125 		isid_ptr = &isid_buf[0];
2126 	}
2127 	/*
2128 	 * Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2129 	 */
2130 	pr_reg_e = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2131 	if (!pr_reg_e) {
2132 		if (res_key) {
2133 			pr_warn("SPC-3 PR: Reservation Key non-zero"
2134 				" for SA REGISTER, returning CONFLICT\n");
2135 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2136 			return -EINVAL;
2137 		}
2138 		/*
2139 		 * Do nothing but return GOOD status.
2140 		 */
2141 		if (!sa_res_key)
2142 			return 0;
2143 
2144 		if (!spec_i_pt) {
2145 			/*
2146 			 * Perform the Service Action REGISTER on the Initiator
2147 			 * Port Endpoint that the PRO was received from on the
2148 			 * Logical Unit of the SCSI device server.
2149 			 */
2150 			ret = core_scsi3_alloc_registration(cmd->se_dev,
2151 					se_sess->se_node_acl, se_deve, isid_ptr,
2152 					sa_res_key, all_tg_pt, aptpl,
2153 					ignore_key, 0);
2154 			if (ret != 0) {
2155 				pr_err("Unable to allocate"
2156 					" struct t10_pr_registration\n");
2157 				cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
2158 				return -EINVAL;
2159 			}
2160 		} else {
2161 			/*
2162 			 * Register both the Initiator port that received
2163 			 * PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2164 			 * TransportID from Parameter list and loop through
2165 			 * fabric dependent parameter list while calling
2166 			 * logic from of core_scsi3_alloc_registration() for
2167 			 * each TransportID provided SCSI Initiator Port/Device
2168 			 */
2169 			ret = core_scsi3_decode_spec_i_port(cmd, se_tpg,
2170 					isid_ptr, sa_res_key, all_tg_pt, aptpl);
2171 			if (ret != 0)
2172 				return ret;
2173 		}
2174 		/*
2175 		 * Nothing left to do for the APTPL=0 case.
2176 		 */
2177 		if (!aptpl) {
2178 			pr_tmpl->pr_aptpl_active = 0;
2179 			core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
2180 			pr_debug("SPC-3 PR: Set APTPL Bit Deactivated for"
2181 					" REGISTER\n");
2182 			return 0;
2183 		}
2184 		/*
2185 		 * Locate the newly allocated local I_T Nexus *pr_reg, and
2186 		 * update the APTPL metadata information using its
2187 		 * preallocated *pr_reg->pr_aptpl_buf.
2188 		 */
2189 		pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev,
2190 				se_sess->se_node_acl, se_sess);
2191 
2192 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2193 				&pr_reg->pr_aptpl_buf[0],
2194 				pr_tmpl->pr_aptpl_buf_len);
2195 		if (!ret) {
2196 			pr_tmpl->pr_aptpl_active = 1;
2197 			pr_debug("SPC-3 PR: Set APTPL Bit Activated for REGISTER\n");
2198 		}
2199 
2200 		core_scsi3_put_pr_reg(pr_reg);
2201 		return ret;
2202 	} else {
2203 		/*
2204 		 * Locate the existing *pr_reg via struct se_node_acl pointers
2205 		 */
2206 		pr_reg = pr_reg_e;
2207 		type = pr_reg->pr_res_type;
2208 
2209 		if (!ignore_key) {
2210 			if (res_key != pr_reg->pr_res_key) {
2211 				pr_err("SPC-3 PR REGISTER: Received"
2212 					" res_key: 0x%016Lx does not match"
2213 					" existing SA REGISTER res_key:"
2214 					" 0x%016Lx\n", res_key,
2215 					pr_reg->pr_res_key);
2216 				core_scsi3_put_pr_reg(pr_reg);
2217 				cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2218 				return -EINVAL;
2219 			}
2220 		}
2221 		if (spec_i_pt) {
2222 			pr_err("SPC-3 PR UNREGISTER: SPEC_I_PT"
2223 				" set while sa_res_key=0\n");
2224 			core_scsi3_put_pr_reg(pr_reg);
2225 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
2226 			return -EINVAL;
2227 		}
2228 		/*
2229 		 * An existing ALL_TG_PT=1 registration being released
2230 		 * must also set ALL_TG_PT=1 in the incoming PROUT.
2231 		 */
2232 		if (pr_reg->pr_reg_all_tg_pt && !(all_tg_pt)) {
2233 			pr_err("SPC-3 PR UNREGISTER: ALL_TG_PT=1"
2234 				" registration exists, but ALL_TG_PT=1 bit not"
2235 				" present in received PROUT\n");
2236 			core_scsi3_put_pr_reg(pr_reg);
2237 			cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
2238 			return -EINVAL;
2239 		}
2240 		/*
2241 		 * Allocate APTPL metadata buffer used for UNREGISTER ops
2242 		 */
2243 		if (aptpl) {
2244 			pr_aptpl_buf = kzalloc(pr_tmpl->pr_aptpl_buf_len,
2245 						GFP_KERNEL);
2246 			if (!pr_aptpl_buf) {
2247 				pr_err("Unable to allocate"
2248 					" pr_aptpl_buf\n");
2249 				core_scsi3_put_pr_reg(pr_reg);
2250 				cmd->scsi_sense_reason =
2251 					TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2252 				return -EINVAL;
2253 			}
2254 		}
2255 		/*
2256 		 * sa_res_key=0 Unregister Reservation Key for registered I_T
2257 		 * Nexus sa_res_key=1 Change Reservation Key for registered I_T
2258 		 * Nexus.
2259 		 */
2260 		if (!sa_res_key) {
2261 			pr_holder = core_scsi3_check_implict_release(
2262 					cmd->se_dev, pr_reg);
2263 			if (pr_holder < 0) {
2264 				kfree(pr_aptpl_buf);
2265 				core_scsi3_put_pr_reg(pr_reg);
2266 				cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2267 				return -EINVAL;
2268 			}
2269 
2270 			spin_lock(&pr_tmpl->registration_lock);
2271 			/*
2272 			 * Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2273 			 * and matching pr_res_key.
2274 			 */
2275 			if (pr_reg->pr_reg_all_tg_pt) {
2276 				list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2277 						&pr_tmpl->registration_list,
2278 						pr_reg_list) {
2279 
2280 					if (!pr_reg_p->pr_reg_all_tg_pt)
2281 						continue;
2282 
2283 					if (pr_reg_p->pr_res_key != res_key)
2284 						continue;
2285 
2286 					if (pr_reg == pr_reg_p)
2287 						continue;
2288 
2289 					if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2290 						   pr_reg_p->pr_reg_nacl->initiatorname))
2291 						continue;
2292 
2293 					__core_scsi3_free_registration(dev,
2294 							pr_reg_p, NULL, 0);
2295 				}
2296 			}
2297 			/*
2298 			 * Release the calling I_T Nexus registration now..
2299 			 */
2300 			__core_scsi3_free_registration(cmd->se_dev, pr_reg,
2301 							NULL, 1);
2302 			/*
2303 			 * From spc4r17, section 5.7.11.3 Unregistering
2304 			 *
2305 			 * If the persistent reservation is a registrants only
2306 			 * type, the device server shall establish a unit
2307 			 * attention condition for the initiator port associated
2308 			 * with every registered I_T nexus except for the I_T
2309 			 * nexus on which the PERSISTENT RESERVE OUT command was
2310 			 * received, with the additional sense code set to
2311 			 * RESERVATIONS RELEASED.
2312 			 */
2313 			if (pr_holder &&
2314 			   ((type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
2315 			    (type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY))) {
2316 				list_for_each_entry(pr_reg_p,
2317 						&pr_tmpl->registration_list,
2318 						pr_reg_list) {
2319 
2320 					core_scsi3_ua_allocate(
2321 						pr_reg_p->pr_reg_nacl,
2322 						pr_reg_p->pr_res_mapped_lun,
2323 						0x2A,
2324 						ASCQ_2AH_RESERVATIONS_RELEASED);
2325 				}
2326 			}
2327 			spin_unlock(&pr_tmpl->registration_lock);
2328 
2329 			if (!aptpl) {
2330 				pr_tmpl->pr_aptpl_active = 0;
2331 				core_scsi3_update_and_write_aptpl(dev, NULL, 0);
2332 				pr_debug("SPC-3 PR: Set APTPL Bit Deactivated"
2333 						" for UNREGISTER\n");
2334 				return 0;
2335 			}
2336 
2337 			ret = core_scsi3_update_and_write_aptpl(dev,
2338 					&pr_aptpl_buf[0],
2339 					pr_tmpl->pr_aptpl_buf_len);
2340 			if (!ret) {
2341 				pr_tmpl->pr_aptpl_active = 1;
2342 				pr_debug("SPC-3 PR: Set APTPL Bit Activated"
2343 						" for UNREGISTER\n");
2344 			}
2345 
2346 			kfree(pr_aptpl_buf);
2347 			return ret;
2348 		} else {
2349 			/*
2350 			 * Increment PRgeneration counter for struct se_device"
2351 			 * upon a successful REGISTER, see spc4r17 section 6.3.2
2352 			 * READ_KEYS service action.
2353 			 */
2354 			pr_reg->pr_res_generation = core_scsi3_pr_generation(
2355 							cmd->se_dev);
2356 			pr_reg->pr_res_key = sa_res_key;
2357 			pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2358 				" Key for %s to: 0x%016Lx PRgeneration:"
2359 				" 0x%08x\n", cmd->se_tfo->get_fabric_name(),
2360 				(ignore_key) ? "_AND_IGNORE_EXISTING_KEY" : "",
2361 				pr_reg->pr_reg_nacl->initiatorname,
2362 				pr_reg->pr_res_key, pr_reg->pr_res_generation);
2363 
2364 			if (!aptpl) {
2365 				pr_tmpl->pr_aptpl_active = 0;
2366 				core_scsi3_update_and_write_aptpl(dev, NULL, 0);
2367 				core_scsi3_put_pr_reg(pr_reg);
2368 				pr_debug("SPC-3 PR: Set APTPL Bit Deactivated"
2369 						" for REGISTER\n");
2370 				return 0;
2371 			}
2372 
2373 			ret = core_scsi3_update_and_write_aptpl(dev,
2374 					&pr_aptpl_buf[0],
2375 					pr_tmpl->pr_aptpl_buf_len);
2376 			if (!ret) {
2377 				pr_tmpl->pr_aptpl_active = 1;
2378 				pr_debug("SPC-3 PR: Set APTPL Bit Activated"
2379 						" for REGISTER\n");
2380 			}
2381 
2382 			kfree(pr_aptpl_buf);
2383 			core_scsi3_put_pr_reg(pr_reg);
2384 		}
2385 	}
2386 	return 0;
2387 }
2388 
2389 unsigned char *core_scsi3_pr_dump_type(int type)
2390 {
2391 	switch (type) {
2392 	case PR_TYPE_WRITE_EXCLUSIVE:
2393 		return "Write Exclusive Access";
2394 	case PR_TYPE_EXCLUSIVE_ACCESS:
2395 		return "Exclusive Access";
2396 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2397 		return "Write Exclusive Access, Registrants Only";
2398 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2399 		return "Exclusive Access, Registrants Only";
2400 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2401 		return "Write Exclusive Access, All Registrants";
2402 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2403 		return "Exclusive Access, All Registrants";
2404 	default:
2405 		break;
2406 	}
2407 
2408 	return "Unknown SPC-3 PR Type";
2409 }
2410 
2411 static int core_scsi3_pro_reserve(
2412 	struct se_cmd *cmd,
2413 	struct se_device *dev,
2414 	int type,
2415 	int scope,
2416 	u64 res_key)
2417 {
2418 	struct se_session *se_sess = cmd->se_sess;
2419 	struct se_dev_entry *se_deve;
2420 	struct se_lun *se_lun = cmd->se_lun;
2421 	struct se_portal_group *se_tpg;
2422 	struct t10_pr_registration *pr_reg, *pr_res_holder;
2423 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2424 	char i_buf[PR_REG_ISID_ID_LEN];
2425 	int ret, prf_isid;
2426 
2427 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2428 
2429 	if (!se_sess || !se_lun) {
2430 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2431 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2432 		return -EINVAL;
2433 	}
2434 	se_tpg = se_sess->se_tpg;
2435 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
2436 	/*
2437 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2438 	 */
2439 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
2440 				se_sess);
2441 	if (!pr_reg) {
2442 		pr_err("SPC-3 PR: Unable to locate"
2443 			" PR_REGISTERED *pr_reg for RESERVE\n");
2444 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2445 		return -EINVAL;
2446 	}
2447 	/*
2448 	 * From spc4r17 Section 5.7.9: Reserving:
2449 	 *
2450 	 * An application client creates a persistent reservation by issuing
2451 	 * a PERSISTENT RESERVE OUT command with RESERVE service action through
2452 	 * a registered I_T nexus with the following parameters:
2453 	 *    a) RESERVATION KEY set to the value of the reservation key that is
2454 	 * 	 registered with the logical unit for the I_T nexus; and
2455 	 */
2456 	if (res_key != pr_reg->pr_res_key) {
2457 		pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2458 			" does not match existing SA REGISTER res_key:"
2459 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2460 		core_scsi3_put_pr_reg(pr_reg);
2461 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2462 		return -EINVAL;
2463 	}
2464 	/*
2465 	 * From spc4r17 Section 5.7.9: Reserving:
2466 	 *
2467 	 * From above:
2468 	 *  b) TYPE field and SCOPE field set to the persistent reservation
2469 	 *     being created.
2470 	 *
2471 	 * Only one persistent reservation is allowed at a time per logical unit
2472 	 * and that persistent reservation has a scope of LU_SCOPE.
2473 	 */
2474 	if (scope != PR_SCOPE_LU_SCOPE) {
2475 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2476 		core_scsi3_put_pr_reg(pr_reg);
2477 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
2478 		return -EINVAL;
2479 	}
2480 	/*
2481 	 * See if we have an existing PR reservation holder pointer at
2482 	 * struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2483 	 * *pr_res_holder.
2484 	 */
2485 	spin_lock(&dev->dev_reservation_lock);
2486 	pr_res_holder = dev->dev_pr_res_holder;
2487 	if ((pr_res_holder)) {
2488 		/*
2489 		 * From spc4r17 Section 5.7.9: Reserving:
2490 		 *
2491 		 * If the device server receives a PERSISTENT RESERVE OUT
2492 		 * command from an I_T nexus other than a persistent reservation
2493 		 * holder (see 5.7.10) that attempts to create a persistent
2494 		 * reservation when a persistent reservation already exists for
2495 		 * the logical unit, then the command shall be completed with
2496 		 * RESERVATION CONFLICT status.
2497 		 */
2498 		if (pr_res_holder != pr_reg) {
2499 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2500 			pr_err("SPC-3 PR: Attempted RESERVE from"
2501 				" [%s]: %s while reservation already held by"
2502 				" [%s]: %s, returning RESERVATION_CONFLICT\n",
2503 				cmd->se_tfo->get_fabric_name(),
2504 				se_sess->se_node_acl->initiatorname,
2505 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2506 				pr_res_holder->pr_reg_nacl->initiatorname);
2507 
2508 			spin_unlock(&dev->dev_reservation_lock);
2509 			core_scsi3_put_pr_reg(pr_reg);
2510 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2511 			return -EINVAL;
2512 		}
2513 		/*
2514 		 * From spc4r17 Section 5.7.9: Reserving:
2515 		 *
2516 		 * If a persistent reservation holder attempts to modify the
2517 		 * type or scope of an existing persistent reservation, the
2518 		 * command shall be completed with RESERVATION CONFLICT status.
2519 		 */
2520 		if ((pr_res_holder->pr_res_type != type) ||
2521 		    (pr_res_holder->pr_res_scope != scope)) {
2522 			struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2523 			pr_err("SPC-3 PR: Attempted RESERVE from"
2524 				" [%s]: %s trying to change TYPE and/or SCOPE,"
2525 				" while reservation already held by [%s]: %s,"
2526 				" returning RESERVATION_CONFLICT\n",
2527 				cmd->se_tfo->get_fabric_name(),
2528 				se_sess->se_node_acl->initiatorname,
2529 				pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2530 				pr_res_holder->pr_reg_nacl->initiatorname);
2531 
2532 			spin_unlock(&dev->dev_reservation_lock);
2533 			core_scsi3_put_pr_reg(pr_reg);
2534 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2535 			return -EINVAL;
2536 		}
2537 		/*
2538 		 * From spc4r17 Section 5.7.9: Reserving:
2539 		 *
2540 		 * If the device server receives a PERSISTENT RESERVE OUT
2541 		 * command with RESERVE service action where the TYPE field and
2542 		 * the SCOPE field contain the same values as the existing type
2543 		 * and scope from a persistent reservation holder, it shall not
2544 		 * make any change to the existing persistent reservation and
2545 		 * shall completethe command with GOOD status.
2546 		 */
2547 		spin_unlock(&dev->dev_reservation_lock);
2548 		core_scsi3_put_pr_reg(pr_reg);
2549 		return 0;
2550 	}
2551 	/*
2552 	 * Otherwise, our *pr_reg becomes the PR reservation holder for said
2553 	 * TYPE/SCOPE.  Also set the received scope and type in *pr_reg.
2554 	 */
2555 	pr_reg->pr_res_scope = scope;
2556 	pr_reg->pr_res_type = type;
2557 	pr_reg->pr_res_holder = 1;
2558 	dev->dev_pr_res_holder = pr_reg;
2559 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2560 				PR_REG_ISID_ID_LEN);
2561 
2562 	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2563 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2564 		cmd->se_tfo->get_fabric_name(), core_scsi3_pr_dump_type(type),
2565 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2566 	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2567 			cmd->se_tfo->get_fabric_name(),
2568 			se_sess->se_node_acl->initiatorname,
2569 			(prf_isid) ? &i_buf[0] : "");
2570 	spin_unlock(&dev->dev_reservation_lock);
2571 
2572 	if (pr_tmpl->pr_aptpl_active) {
2573 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2574 				&pr_reg->pr_aptpl_buf[0],
2575 				pr_tmpl->pr_aptpl_buf_len);
2576 		if (!ret)
2577 			pr_debug("SPC-3 PR: Updated APTPL metadata"
2578 					" for RESERVE\n");
2579 	}
2580 
2581 	core_scsi3_put_pr_reg(pr_reg);
2582 	return 0;
2583 }
2584 
2585 static int core_scsi3_emulate_pro_reserve(
2586 	struct se_cmd *cmd,
2587 	int type,
2588 	int scope,
2589 	u64 res_key)
2590 {
2591 	struct se_device *dev = cmd->se_dev;
2592 	int ret = 0;
2593 
2594 	switch (type) {
2595 	case PR_TYPE_WRITE_EXCLUSIVE:
2596 	case PR_TYPE_EXCLUSIVE_ACCESS:
2597 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2598 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2599 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2600 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2601 		ret = core_scsi3_pro_reserve(cmd, dev, type, scope, res_key);
2602 		break;
2603 	default:
2604 		pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2605 			" 0x%02x\n", type);
2606 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
2607 		return -EINVAL;
2608 	}
2609 
2610 	return ret;
2611 }
2612 
2613 /*
2614  * Called with struct se_device->dev_reservation_lock held.
2615  */
2616 static void __core_scsi3_complete_pro_release(
2617 	struct se_device *dev,
2618 	struct se_node_acl *se_nacl,
2619 	struct t10_pr_registration *pr_reg,
2620 	int explict)
2621 {
2622 	struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2623 	char i_buf[PR_REG_ISID_ID_LEN];
2624 	int prf_isid;
2625 
2626 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2627 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2628 				PR_REG_ISID_ID_LEN);
2629 	/*
2630 	 * Go ahead and release the current PR reservation holder.
2631 	 */
2632 	dev->dev_pr_res_holder = NULL;
2633 
2634 	pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2635 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2636 		tfo->get_fabric_name(), (explict) ? "explict" : "implict",
2637 		core_scsi3_pr_dump_type(pr_reg->pr_res_type),
2638 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2639 	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2640 		tfo->get_fabric_name(), se_nacl->initiatorname,
2641 		(prf_isid) ? &i_buf[0] : "");
2642 	/*
2643 	 * Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2644 	 */
2645 	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2646 }
2647 
2648 static int core_scsi3_emulate_pro_release(
2649 	struct se_cmd *cmd,
2650 	int type,
2651 	int scope,
2652 	u64 res_key)
2653 {
2654 	struct se_device *dev = cmd->se_dev;
2655 	struct se_session *se_sess = cmd->se_sess;
2656 	struct se_lun *se_lun = cmd->se_lun;
2657 	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2658 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2659 	int ret, all_reg = 0;
2660 
2661 	if (!se_sess || !se_lun) {
2662 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2663 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2664 		return -EINVAL;
2665 	}
2666 	/*
2667 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2668 	 */
2669 	pr_reg = core_scsi3_locate_pr_reg(dev, se_sess->se_node_acl, se_sess);
2670 	if (!pr_reg) {
2671 		pr_err("SPC-3 PR: Unable to locate"
2672 			" PR_REGISTERED *pr_reg for RELEASE\n");
2673 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2674 		return -EINVAL;
2675 	}
2676 	/*
2677 	 * From spc4r17 Section 5.7.11.2 Releasing:
2678 	 *
2679 	 * If there is no persistent reservation or in response to a persistent
2680 	 * reservation release request from a registered I_T nexus that is not a
2681 	 * persistent reservation holder (see 5.7.10), the device server shall
2682 	 * do the following:
2683 	 *
2684 	 *     a) Not release the persistent reservation, if any;
2685 	 *     b) Not remove any registrations; and
2686 	 *     c) Complete the command with GOOD status.
2687 	 */
2688 	spin_lock(&dev->dev_reservation_lock);
2689 	pr_res_holder = dev->dev_pr_res_holder;
2690 	if (!pr_res_holder) {
2691 		/*
2692 		 * No persistent reservation, return GOOD status.
2693 		 */
2694 		spin_unlock(&dev->dev_reservation_lock);
2695 		core_scsi3_put_pr_reg(pr_reg);
2696 		return 0;
2697 	}
2698 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2699 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
2700 		all_reg = 1;
2701 
2702 	if ((all_reg == 0) && (pr_res_holder != pr_reg)) {
2703 		/*
2704 		 * Non 'All Registrants' PR Type cases..
2705 		 * Release request from a registered I_T nexus that is not a
2706 		 * persistent reservation holder. return GOOD status.
2707 		 */
2708 		spin_unlock(&dev->dev_reservation_lock);
2709 		core_scsi3_put_pr_reg(pr_reg);
2710 		return 0;
2711 	}
2712 	/*
2713 	 * From spc4r17 Section 5.7.11.2 Releasing:
2714 	 *
2715 	 * Only the persistent reservation holder (see 5.7.10) is allowed to
2716 	 * release a persistent reservation.
2717 	 *
2718 	 * An application client releases the persistent reservation by issuing
2719 	 * a PERSISTENT RESERVE OUT command with RELEASE service action through
2720 	 * an I_T nexus that is a persistent reservation holder with the
2721 	 * following parameters:
2722 	 *
2723 	 *     a) RESERVATION KEY field set to the value of the reservation key
2724 	 *	  that is registered with the logical unit for the I_T nexus;
2725 	 */
2726 	if (res_key != pr_reg->pr_res_key) {
2727 		pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2728 			" does not match existing SA REGISTER res_key:"
2729 			" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2730 		spin_unlock(&dev->dev_reservation_lock);
2731 		core_scsi3_put_pr_reg(pr_reg);
2732 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2733 		return -EINVAL;
2734 	}
2735 	/*
2736 	 * From spc4r17 Section 5.7.11.2 Releasing and above:
2737 	 *
2738 	 * b) TYPE field and SCOPE field set to match the persistent
2739 	 *    reservation being released.
2740 	 */
2741 	if ((pr_res_holder->pr_res_type != type) ||
2742 	    (pr_res_holder->pr_res_scope != scope)) {
2743 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2744 		pr_err("SPC-3 PR RELEASE: Attempted to release"
2745 			" reservation from [%s]: %s with different TYPE "
2746 			"and/or SCOPE  while reservation already held by"
2747 			" [%s]: %s, returning RESERVATION_CONFLICT\n",
2748 			cmd->se_tfo->get_fabric_name(),
2749 			se_sess->se_node_acl->initiatorname,
2750 			pr_res_nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
2751 			pr_res_holder->pr_reg_nacl->initiatorname);
2752 
2753 		spin_unlock(&dev->dev_reservation_lock);
2754 		core_scsi3_put_pr_reg(pr_reg);
2755 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2756 		return -EINVAL;
2757 	}
2758 	/*
2759 	 * In response to a persistent reservation release request from the
2760 	 * persistent reservation holder the device server shall perform a
2761 	 * release by doing the following as an uninterrupted series of actions:
2762 	 * a) Release the persistent reservation;
2763 	 * b) Not remove any registration(s);
2764 	 * c) If the released persistent reservation is a registrants only type
2765 	 * or all registrants type persistent reservation,
2766 	 *    the device server shall establish a unit attention condition for
2767 	 *    the initiator port associated with every regis-
2768 	 *    tered I_T nexus other than I_T nexus on which the PERSISTENT
2769 	 *    RESERVE OUT command with RELEASE service action was received,
2770 	 *    with the additional sense code set to RESERVATIONS RELEASED; and
2771 	 * d) If the persistent reservation is of any other type, the device
2772 	 *    server shall not establish a unit attention condition.
2773 	 */
2774 	__core_scsi3_complete_pro_release(dev, se_sess->se_node_acl,
2775 			pr_reg, 1);
2776 
2777 	spin_unlock(&dev->dev_reservation_lock);
2778 
2779 	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2780 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2781 	    (type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2782 	    (type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2783 		/*
2784 		 * If no UNIT ATTENTION conditions will be established for
2785 		 * PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2786 		 * go ahead and check for APTPL=1 update+write below
2787 		 */
2788 		goto write_aptpl;
2789 	}
2790 
2791 	spin_lock(&pr_tmpl->registration_lock);
2792 	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2793 			pr_reg_list) {
2794 		/*
2795 		 * Do not establish a UNIT ATTENTION condition
2796 		 * for the calling I_T Nexus
2797 		 */
2798 		if (pr_reg_p == pr_reg)
2799 			continue;
2800 
2801 		core_scsi3_ua_allocate(pr_reg_p->pr_reg_nacl,
2802 				pr_reg_p->pr_res_mapped_lun,
2803 				0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2804 	}
2805 	spin_unlock(&pr_tmpl->registration_lock);
2806 
2807 write_aptpl:
2808 	if (pr_tmpl->pr_aptpl_active) {
2809 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
2810 				&pr_reg->pr_aptpl_buf[0],
2811 				pr_tmpl->pr_aptpl_buf_len);
2812 		if (!ret)
2813 			pr_debug("SPC-3 PR: Updated APTPL metadata for RELEASE\n");
2814 	}
2815 
2816 	core_scsi3_put_pr_reg(pr_reg);
2817 	return 0;
2818 }
2819 
2820 static int core_scsi3_emulate_pro_clear(
2821 	struct se_cmd *cmd,
2822 	u64 res_key)
2823 {
2824 	struct se_device *dev = cmd->se_dev;
2825 	struct se_node_acl *pr_reg_nacl;
2826 	struct se_session *se_sess = cmd->se_sess;
2827 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2828 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2829 	u32 pr_res_mapped_lun = 0;
2830 	int calling_it_nexus = 0;
2831 	/*
2832 	 * Locate the existing *pr_reg via struct se_node_acl pointers
2833 	 */
2834 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev,
2835 			se_sess->se_node_acl, se_sess);
2836 	if (!pr_reg_n) {
2837 		pr_err("SPC-3 PR: Unable to locate"
2838 			" PR_REGISTERED *pr_reg for CLEAR\n");
2839 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2840 		return -EINVAL;
2841 	}
2842 	/*
2843 	 * From spc4r17 section 5.7.11.6, Clearing:
2844 	 *
2845 	 * Any application client may release the persistent reservation and
2846 	 * remove all registrations from a device server by issuing a
2847 	 * PERSISTENT RESERVE OUT command with CLEAR service action through a
2848 	 * registered I_T nexus with the following parameter:
2849 	 *
2850 	 *	a) RESERVATION KEY field set to the value of the reservation key
2851 	 * 	   that is registered with the logical unit for the I_T nexus.
2852 	 */
2853 	if (res_key != pr_reg_n->pr_res_key) {
2854 		pr_err("SPC-3 PR REGISTER: Received"
2855 			" res_key: 0x%016Lx does not match"
2856 			" existing SA REGISTER res_key:"
2857 			" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2858 		core_scsi3_put_pr_reg(pr_reg_n);
2859 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
2860 		return -EINVAL;
2861 	}
2862 	/*
2863 	 * a) Release the persistent reservation, if any;
2864 	 */
2865 	spin_lock(&dev->dev_reservation_lock);
2866 	pr_res_holder = dev->dev_pr_res_holder;
2867 	if (pr_res_holder) {
2868 		struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2869 		__core_scsi3_complete_pro_release(dev, pr_res_nacl,
2870 			pr_res_holder, 0);
2871 	}
2872 	spin_unlock(&dev->dev_reservation_lock);
2873 	/*
2874 	 * b) Remove all registration(s) (see spc4r17 5.7.7);
2875 	 */
2876 	spin_lock(&pr_tmpl->registration_lock);
2877 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2878 			&pr_tmpl->registration_list, pr_reg_list) {
2879 
2880 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2881 		pr_reg_nacl = pr_reg->pr_reg_nacl;
2882 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2883 		__core_scsi3_free_registration(dev, pr_reg, NULL,
2884 					calling_it_nexus);
2885 		/*
2886 		 * e) Establish a unit attention condition for the initiator
2887 		 *    port associated with every registered I_T nexus other
2888 		 *    than the I_T nexus on which the PERSISTENT RESERVE OUT
2889 		 *    command with CLEAR service action was received, with the
2890 		 *    additional sense code set to RESERVATIONS PREEMPTED.
2891 		 */
2892 		if (!calling_it_nexus)
2893 			core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun,
2894 				0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2895 	}
2896 	spin_unlock(&pr_tmpl->registration_lock);
2897 
2898 	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2899 		cmd->se_tfo->get_fabric_name());
2900 
2901 	if (pr_tmpl->pr_aptpl_active) {
2902 		core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
2903 		pr_debug("SPC-3 PR: Updated APTPL metadata"
2904 				" for CLEAR\n");
2905 	}
2906 
2907 	core_scsi3_pr_generation(dev);
2908 	return 0;
2909 }
2910 
2911 /*
2912  * Called with struct se_device->dev_reservation_lock held.
2913  */
2914 static void __core_scsi3_complete_pro_preempt(
2915 	struct se_device *dev,
2916 	struct t10_pr_registration *pr_reg,
2917 	struct list_head *preempt_and_abort_list,
2918 	int type,
2919 	int scope,
2920 	int abort)
2921 {
2922 	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2923 	struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2924 	char i_buf[PR_REG_ISID_ID_LEN];
2925 	int prf_isid;
2926 
2927 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
2928 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
2929 				PR_REG_ISID_ID_LEN);
2930 	/*
2931 	 * Do an implict RELEASE of the existing reservation.
2932 	 */
2933 	if (dev->dev_pr_res_holder)
2934 		__core_scsi3_complete_pro_release(dev, nacl,
2935 				dev->dev_pr_res_holder, 0);
2936 
2937 	dev->dev_pr_res_holder = pr_reg;
2938 	pr_reg->pr_res_holder = 1;
2939 	pr_reg->pr_res_type = type;
2940 	pr_reg->pr_res_scope = scope;
2941 
2942 	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2943 		" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2944 		tfo->get_fabric_name(), (abort) ? "_AND_ABORT" : "",
2945 		core_scsi3_pr_dump_type(type),
2946 		(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2947 	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2948 		tfo->get_fabric_name(), (abort) ? "_AND_ABORT" : "",
2949 		nacl->initiatorname, (prf_isid) ? &i_buf[0] : "");
2950 	/*
2951 	 * For PREEMPT_AND_ABORT, add the preempting reservation's
2952 	 * struct t10_pr_registration to the list that will be compared
2953 	 * against received CDBs..
2954 	 */
2955 	if (preempt_and_abort_list)
2956 		list_add_tail(&pr_reg->pr_reg_abort_list,
2957 				preempt_and_abort_list);
2958 }
2959 
2960 static void core_scsi3_release_preempt_and_abort(
2961 	struct list_head *preempt_and_abort_list,
2962 	struct t10_pr_registration *pr_reg_holder)
2963 {
2964 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2965 
2966 	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2967 				pr_reg_abort_list) {
2968 
2969 		list_del(&pr_reg->pr_reg_abort_list);
2970 		if (pr_reg_holder == pr_reg)
2971 			continue;
2972 		if (pr_reg->pr_res_holder) {
2973 			pr_warn("pr_reg->pr_res_holder still set\n");
2974 			continue;
2975 		}
2976 
2977 		pr_reg->pr_reg_deve = NULL;
2978 		pr_reg->pr_reg_nacl = NULL;
2979 		kfree(pr_reg->pr_aptpl_buf);
2980 		kmem_cache_free(t10_pr_reg_cache, pr_reg);
2981 	}
2982 }
2983 
2984 static int core_scsi3_pro_preempt(
2985 	struct se_cmd *cmd,
2986 	int type,
2987 	int scope,
2988 	u64 res_key,
2989 	u64 sa_res_key,
2990 	int abort)
2991 {
2992 	struct se_device *dev = cmd->se_dev;
2993 	struct se_dev_entry *se_deve;
2994 	struct se_node_acl *pr_reg_nacl;
2995 	struct se_session *se_sess = cmd->se_sess;
2996 	LIST_HEAD(preempt_and_abort_list);
2997 	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2998 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
2999 	u32 pr_res_mapped_lun = 0;
3000 	int all_reg = 0, calling_it_nexus = 0, released_regs = 0;
3001 	int prh_type = 0, prh_scope = 0, ret;
3002 
3003 	if (!se_sess) {
3004 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3005 		return -EINVAL;
3006 	}
3007 
3008 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
3009 	pr_reg_n = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3010 				se_sess);
3011 	if (!pr_reg_n) {
3012 		pr_err("SPC-3 PR: Unable to locate"
3013 			" PR_REGISTERED *pr_reg for PREEMPT%s\n",
3014 			(abort) ? "_AND_ABORT" : "");
3015 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3016 		return -EINVAL;
3017 	}
3018 	if (pr_reg_n->pr_res_key != res_key) {
3019 		core_scsi3_put_pr_reg(pr_reg_n);
3020 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3021 		return -EINVAL;
3022 	}
3023 	if (scope != PR_SCOPE_LU_SCOPE) {
3024 		pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
3025 		core_scsi3_put_pr_reg(pr_reg_n);
3026 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3027 		return -EINVAL;
3028 	}
3029 
3030 	spin_lock(&dev->dev_reservation_lock);
3031 	pr_res_holder = dev->dev_pr_res_holder;
3032 	if (pr_res_holder &&
3033 	   ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3034 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
3035 		all_reg = 1;
3036 
3037 	if (!all_reg && !sa_res_key) {
3038 		spin_unlock(&dev->dev_reservation_lock);
3039 		core_scsi3_put_pr_reg(pr_reg_n);
3040 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3041 		return -EINVAL;
3042 	}
3043 	/*
3044 	 * From spc4r17, section 5.7.11.4.4 Removing Registrations:
3045 	 *
3046 	 * If the SERVICE ACTION RESERVATION KEY field does not identify a
3047 	 * persistent reservation holder or there is no persistent reservation
3048 	 * holder (i.e., there is no persistent reservation), then the device
3049 	 * server shall perform a preempt by doing the following in an
3050 	 * uninterrupted series of actions. (See below..)
3051 	 */
3052 	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
3053 		/*
3054 		 * No existing or SA Reservation Key matching reservations..
3055 		 *
3056 		 * PROUT SA PREEMPT with All Registrant type reservations are
3057 		 * allowed to be processed without a matching SA Reservation Key
3058 		 */
3059 		spin_lock(&pr_tmpl->registration_lock);
3060 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3061 				&pr_tmpl->registration_list, pr_reg_list) {
3062 			/*
3063 			 * Removing of registrations in non all registrants
3064 			 * type reservations without a matching SA reservation
3065 			 * key.
3066 			 *
3067 			 * a) Remove the registrations for all I_T nexuses
3068 			 *    specified by the SERVICE ACTION RESERVATION KEY
3069 			 *    field;
3070 			 * b) Ignore the contents of the SCOPE and TYPE fields;
3071 			 * c) Process tasks as defined in 5.7.1; and
3072 			 * d) Establish a unit attention condition for the
3073 			 *    initiator port associated with every I_T nexus
3074 			 *    that lost its registration other than the I_T
3075 			 *    nexus on which the PERSISTENT RESERVE OUT command
3076 			 *    was received, with the additional sense code set
3077 			 *    to REGISTRATIONS PREEMPTED.
3078 			 */
3079 			if (!all_reg) {
3080 				if (pr_reg->pr_res_key != sa_res_key)
3081 					continue;
3082 
3083 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3084 				pr_reg_nacl = pr_reg->pr_reg_nacl;
3085 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3086 				__core_scsi3_free_registration(dev, pr_reg,
3087 					(abort) ? &preempt_and_abort_list :
3088 						NULL, calling_it_nexus);
3089 				released_regs++;
3090 			} else {
3091 				/*
3092 				 * Case for any existing all registrants type
3093 				 * reservation, follow logic in spc4r17 section
3094 				 * 5.7.11.4 Preempting, Table 52 and Figure 7.
3095 				 *
3096 				 * For a ZERO SA Reservation key, release
3097 				 * all other registrations and do an implict
3098 				 * release of active persistent reservation.
3099 				 *
3100 				 * For a non-ZERO SA Reservation key, only
3101 				 * release the matching reservation key from
3102 				 * registrations.
3103 				 */
3104 				if ((sa_res_key) &&
3105 				     (pr_reg->pr_res_key != sa_res_key))
3106 					continue;
3107 
3108 				calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3109 				if (calling_it_nexus)
3110 					continue;
3111 
3112 				pr_reg_nacl = pr_reg->pr_reg_nacl;
3113 				pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3114 				__core_scsi3_free_registration(dev, pr_reg,
3115 					(abort) ? &preempt_and_abort_list :
3116 						NULL, 0);
3117 				released_regs++;
3118 			}
3119 			if (!calling_it_nexus)
3120 				core_scsi3_ua_allocate(pr_reg_nacl,
3121 					pr_res_mapped_lun, 0x2A,
3122 					ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3123 		}
3124 		spin_unlock(&pr_tmpl->registration_lock);
3125 		/*
3126 		 * If a PERSISTENT RESERVE OUT with a PREEMPT service action or
3127 		 * a PREEMPT AND ABORT service action sets the SERVICE ACTION
3128 		 * RESERVATION KEY field to a value that does not match any
3129 		 * registered reservation key, then the device server shall
3130 		 * complete the command with RESERVATION CONFLICT status.
3131 		 */
3132 		if (!released_regs) {
3133 			spin_unlock(&dev->dev_reservation_lock);
3134 			core_scsi3_put_pr_reg(pr_reg_n);
3135 			cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3136 			return -EINVAL;
3137 		}
3138 		/*
3139 		 * For an existing all registrants type reservation
3140 		 * with a zero SA rservation key, preempt the existing
3141 		 * reservation with the new PR type and scope.
3142 		 */
3143 		if (pr_res_holder && all_reg && !(sa_res_key)) {
3144 			__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3145 				(abort) ? &preempt_and_abort_list : NULL,
3146 				type, scope, abort);
3147 
3148 			if (abort)
3149 				core_scsi3_release_preempt_and_abort(
3150 					&preempt_and_abort_list, pr_reg_n);
3151 		}
3152 		spin_unlock(&dev->dev_reservation_lock);
3153 
3154 		if (pr_tmpl->pr_aptpl_active) {
3155 			ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3156 					&pr_reg_n->pr_aptpl_buf[0],
3157 					pr_tmpl->pr_aptpl_buf_len);
3158 			if (!ret)
3159 				pr_debug("SPC-3 PR: Updated APTPL"
3160 					" metadata for  PREEMPT%s\n", (abort) ?
3161 					"_AND_ABORT" : "");
3162 		}
3163 
3164 		core_scsi3_put_pr_reg(pr_reg_n);
3165 		core_scsi3_pr_generation(cmd->se_dev);
3166 		return 0;
3167 	}
3168 	/*
3169 	 * The PREEMPTing SA reservation key matches that of the
3170 	 * existing persistent reservation, first, we check if
3171 	 * we are preempting our own reservation.
3172 	 * From spc4r17, section 5.7.11.4.3 Preempting
3173 	 * persistent reservations and registration handling
3174 	 *
3175 	 * If an all registrants persistent reservation is not
3176 	 * present, it is not an error for the persistent
3177 	 * reservation holder to preempt itself (i.e., a
3178 	 * PERSISTENT RESERVE OUT with a PREEMPT service action
3179 	 * or a PREEMPT AND ABORT service action with the
3180 	 * SERVICE ACTION RESERVATION KEY value equal to the
3181 	 * persistent reservation holder's reservation key that
3182 	 * is received from the persistent reservation holder).
3183 	 * In that case, the device server shall establish the
3184 	 * new persistent reservation and maintain the
3185 	 * registration.
3186 	 */
3187 	prh_type = pr_res_holder->pr_res_type;
3188 	prh_scope = pr_res_holder->pr_res_scope;
3189 	/*
3190 	 * If the SERVICE ACTION RESERVATION KEY field identifies a
3191 	 * persistent reservation holder (see 5.7.10), the device
3192 	 * server shall perform a preempt by doing the following as
3193 	 * an uninterrupted series of actions:
3194 	 *
3195 	 * a) Release the persistent reservation for the holder
3196 	 *    identified by the SERVICE ACTION RESERVATION KEY field;
3197 	 */
3198 	if (pr_reg_n != pr_res_holder)
3199 		__core_scsi3_complete_pro_release(dev,
3200 				pr_res_holder->pr_reg_nacl,
3201 				dev->dev_pr_res_holder, 0);
3202 	/*
3203 	 * b) Remove the registrations for all I_T nexuses identified
3204 	 *    by the SERVICE ACTION RESERVATION KEY field, except the
3205 	 *    I_T nexus that is being used for the PERSISTENT RESERVE
3206 	 *    OUT command. If an all registrants persistent reservation
3207 	 *    is present and the SERVICE ACTION RESERVATION KEY field
3208 	 *    is set to zero, then all registrations shall be removed
3209 	 *    except for that of the I_T nexus that is being used for
3210 	 *    the PERSISTENT RESERVE OUT command;
3211 	 */
3212 	spin_lock(&pr_tmpl->registration_lock);
3213 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3214 			&pr_tmpl->registration_list, pr_reg_list) {
3215 
3216 		calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3217 		if (calling_it_nexus)
3218 			continue;
3219 
3220 		if (pr_reg->pr_res_key != sa_res_key)
3221 			continue;
3222 
3223 		pr_reg_nacl = pr_reg->pr_reg_nacl;
3224 		pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3225 		__core_scsi3_free_registration(dev, pr_reg,
3226 				(abort) ? &preempt_and_abort_list : NULL,
3227 				calling_it_nexus);
3228 		/*
3229 		 * e) Establish a unit attention condition for the initiator
3230 		 *    port associated with every I_T nexus that lost its
3231 		 *    persistent reservation and/or registration, with the
3232 		 *    additional sense code set to REGISTRATIONS PREEMPTED;
3233 		 */
3234 		core_scsi3_ua_allocate(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3235 				ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3236 	}
3237 	spin_unlock(&pr_tmpl->registration_lock);
3238 	/*
3239 	 * c) Establish a persistent reservation for the preempting
3240 	 *    I_T nexus using the contents of the SCOPE and TYPE fields;
3241 	 */
3242 	__core_scsi3_complete_pro_preempt(dev, pr_reg_n,
3243 			(abort) ? &preempt_and_abort_list : NULL,
3244 			type, scope, abort);
3245 	/*
3246 	 * d) Process tasks as defined in 5.7.1;
3247 	 * e) See above..
3248 	 * f) If the type or scope has changed, then for every I_T nexus
3249 	 *    whose reservation key was not removed, except for the I_T
3250 	 *    nexus on which the PERSISTENT RESERVE OUT command was
3251 	 *    received, the device server shall establish a unit
3252 	 *    attention condition for the initiator port associated with
3253 	 *    that I_T nexus, with the additional sense code set to
3254 	 *    RESERVATIONS RELEASED. If the type or scope have not
3255 	 *    changed, then no unit attention condition(s) shall be
3256 	 *    established for this reason.
3257 	 */
3258 	if ((prh_type != type) || (prh_scope != scope)) {
3259 		spin_lock(&pr_tmpl->registration_lock);
3260 		list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3261 				&pr_tmpl->registration_list, pr_reg_list) {
3262 
3263 			calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3264 			if (calling_it_nexus)
3265 				continue;
3266 
3267 			core_scsi3_ua_allocate(pr_reg->pr_reg_nacl,
3268 					pr_reg->pr_res_mapped_lun, 0x2A,
3269 					ASCQ_2AH_RESERVATIONS_RELEASED);
3270 		}
3271 		spin_unlock(&pr_tmpl->registration_lock);
3272 	}
3273 	spin_unlock(&dev->dev_reservation_lock);
3274 	/*
3275 	 * Call LUN_RESET logic upon list of struct t10_pr_registration,
3276 	 * All received CDBs for the matching existing reservation and
3277 	 * registrations undergo ABORT_TASK logic.
3278 	 *
3279 	 * From there, core_scsi3_release_preempt_and_abort() will
3280 	 * release every registration in the list (which have already
3281 	 * been removed from the primary pr_reg list), except the
3282 	 * new persistent reservation holder, the calling Initiator Port.
3283 	 */
3284 	if (abort) {
3285 		core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3286 		core_scsi3_release_preempt_and_abort(&preempt_and_abort_list,
3287 						pr_reg_n);
3288 	}
3289 
3290 	if (pr_tmpl->pr_aptpl_active) {
3291 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3292 				&pr_reg_n->pr_aptpl_buf[0],
3293 				pr_tmpl->pr_aptpl_buf_len);
3294 		if (!ret)
3295 			pr_debug("SPC-3 PR: Updated APTPL metadata for PREEMPT"
3296 				"%s\n", (abort) ? "_AND_ABORT" : "");
3297 	}
3298 
3299 	core_scsi3_put_pr_reg(pr_reg_n);
3300 	core_scsi3_pr_generation(cmd->se_dev);
3301 	return 0;
3302 }
3303 
3304 static int core_scsi3_emulate_pro_preempt(
3305 	struct se_cmd *cmd,
3306 	int type,
3307 	int scope,
3308 	u64 res_key,
3309 	u64 sa_res_key,
3310 	int abort)
3311 {
3312 	int ret = 0;
3313 
3314 	switch (type) {
3315 	case PR_TYPE_WRITE_EXCLUSIVE:
3316 	case PR_TYPE_EXCLUSIVE_ACCESS:
3317 	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3318 	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3319 	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3320 	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3321 		ret = core_scsi3_pro_preempt(cmd, type, scope,
3322 				res_key, sa_res_key, abort);
3323 		break;
3324 	default:
3325 		pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3326 			" Type: 0x%02x\n", (abort) ? "_AND_ABORT" : "", type);
3327 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3328 		return -EINVAL;
3329 	}
3330 
3331 	return ret;
3332 }
3333 
3334 
3335 static int core_scsi3_emulate_pro_register_and_move(
3336 	struct se_cmd *cmd,
3337 	u64 res_key,
3338 	u64 sa_res_key,
3339 	int aptpl,
3340 	int unreg)
3341 {
3342 	struct se_session *se_sess = cmd->se_sess;
3343 	struct se_device *dev = cmd->se_dev;
3344 	struct se_dev_entry *se_deve, *dest_se_deve = NULL;
3345 	struct se_lun *se_lun = cmd->se_lun;
3346 	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3347 	struct se_port *se_port;
3348 	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3349 	struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3350 	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3351 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
3352 	unsigned char *buf;
3353 	unsigned char *initiator_str;
3354 	char *iport_ptr = NULL, dest_iport[64], i_buf[PR_REG_ISID_ID_LEN];
3355 	u32 tid_len, tmp_tid_len;
3356 	int new_reg = 0, type, scope, ret, matching_iname, prf_isid;
3357 	unsigned short rtpi;
3358 	unsigned char proto_ident;
3359 
3360 	if (!se_sess || !se_lun) {
3361 		pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3362 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3363 		return -EINVAL;
3364 	}
3365 	memset(dest_iport, 0, 64);
3366 	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
3367 	se_tpg = se_sess->se_tpg;
3368 	tf_ops = se_tpg->se_tpg_tfo;
3369 	se_deve = &se_sess->se_node_acl->device_list[cmd->orig_fe_lun];
3370 	/*
3371 	 * Follow logic from spc4r17 Section 5.7.8, Table 50 --
3372 	 *	Register behaviors for a REGISTER AND MOVE service action
3373 	 *
3374 	 * Locate the existing *pr_reg via struct se_node_acl pointers
3375 	 */
3376 	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
3377 				se_sess);
3378 	if (!pr_reg) {
3379 		pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3380 			" *pr_reg for REGISTER_AND_MOVE\n");
3381 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3382 		return -EINVAL;
3383 	}
3384 	/*
3385 	 * The provided reservation key much match the existing reservation key
3386 	 * provided during this initiator's I_T nexus registration.
3387 	 */
3388 	if (res_key != pr_reg->pr_res_key) {
3389 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3390 			" res_key: 0x%016Lx does not match existing SA REGISTER"
3391 			" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3392 		core_scsi3_put_pr_reg(pr_reg);
3393 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3394 		return -EINVAL;
3395 	}
3396 	/*
3397 	 * The service active reservation key needs to be non zero
3398 	 */
3399 	if (!sa_res_key) {
3400 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3401 			" sa_res_key\n");
3402 		core_scsi3_put_pr_reg(pr_reg);
3403 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3404 		return -EINVAL;
3405 	}
3406 
3407 	/*
3408 	 * Determine the Relative Target Port Identifier where the reservation
3409 	 * will be moved to for the TransportID containing SCSI initiator WWN
3410 	 * information.
3411 	 */
3412 	buf = transport_kmap_data_sg(cmd);
3413 	rtpi = (buf[18] & 0xff) << 8;
3414 	rtpi |= buf[19] & 0xff;
3415 	tid_len = (buf[20] & 0xff) << 24;
3416 	tid_len |= (buf[21] & 0xff) << 16;
3417 	tid_len |= (buf[22] & 0xff) << 8;
3418 	tid_len |= buf[23] & 0xff;
3419 	transport_kunmap_data_sg(cmd);
3420 	buf = NULL;
3421 
3422 	if ((tid_len + 24) != cmd->data_length) {
3423 		pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3424 			" does not equal CDB data_length: %u\n", tid_len,
3425 			cmd->data_length);
3426 		core_scsi3_put_pr_reg(pr_reg);
3427 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3428 		return -EINVAL;
3429 	}
3430 
3431 	spin_lock(&dev->se_port_lock);
3432 	list_for_each_entry(se_port, &dev->dev_sep_list, sep_list) {
3433 		if (se_port->sep_rtpi != rtpi)
3434 			continue;
3435 		dest_se_tpg = se_port->sep_tpg;
3436 		if (!dest_se_tpg)
3437 			continue;
3438 		dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3439 		if (!dest_tf_ops)
3440 			continue;
3441 
3442 		atomic_inc(&dest_se_tpg->tpg_pr_ref_count);
3443 		smp_mb__after_atomic_inc();
3444 		spin_unlock(&dev->se_port_lock);
3445 
3446 		ret = core_scsi3_tpg_depend_item(dest_se_tpg);
3447 		if (ret != 0) {
3448 			pr_err("core_scsi3_tpg_depend_item() failed"
3449 				" for dest_se_tpg\n");
3450 			atomic_dec(&dest_se_tpg->tpg_pr_ref_count);
3451 			smp_mb__after_atomic_dec();
3452 			core_scsi3_put_pr_reg(pr_reg);
3453 			cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3454 			return -EINVAL;
3455 		}
3456 
3457 		spin_lock(&dev->se_port_lock);
3458 		break;
3459 	}
3460 	spin_unlock(&dev->se_port_lock);
3461 
3462 	if (!dest_se_tpg || !dest_tf_ops) {
3463 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3464 			" fabric ops from Relative Target Port Identifier:"
3465 			" %hu\n", rtpi);
3466 		core_scsi3_put_pr_reg(pr_reg);
3467 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3468 		return -EINVAL;
3469 	}
3470 
3471 	buf = transport_kmap_data_sg(cmd);
3472 	proto_ident = (buf[24] & 0x0f);
3473 #if 0
3474 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3475 			" 0x%02x\n", proto_ident);
3476 #endif
3477 	if (proto_ident != dest_tf_ops->get_fabric_proto_ident(dest_se_tpg)) {
3478 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3479 			" proto_ident: 0x%02x does not match ident: 0x%02x"
3480 			" from fabric: %s\n", proto_ident,
3481 			dest_tf_ops->get_fabric_proto_ident(dest_se_tpg),
3482 			dest_tf_ops->get_fabric_name());
3483 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3484 		ret = -EINVAL;
3485 		goto out;
3486 	}
3487 	if (dest_tf_ops->tpg_parse_pr_out_transport_id == NULL) {
3488 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Fabric does not"
3489 			" containg a valid tpg_parse_pr_out_transport_id"
3490 			" function pointer\n");
3491 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3492 		ret = -EINVAL;
3493 		goto out;
3494 	}
3495 	initiator_str = dest_tf_ops->tpg_parse_pr_out_transport_id(dest_se_tpg,
3496 			(const char *)&buf[24], &tmp_tid_len, &iport_ptr);
3497 	if (!initiator_str) {
3498 		pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3499 			" initiator_str from Transport ID\n");
3500 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3501 		ret = -EINVAL;
3502 		goto out;
3503 	}
3504 
3505 	transport_kunmap_data_sg(cmd);
3506 	buf = NULL;
3507 
3508 	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3509 		" %s\n", dest_tf_ops->get_fabric_name(), (iport_ptr != NULL) ?
3510 		"port" : "device", initiator_str, (iport_ptr != NULL) ?
3511 		iport_ptr : "");
3512 	/*
3513 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3514 	 * action specifies a TransportID that is the same as the initiator port
3515 	 * of the I_T nexus for the command received, then the command shall
3516 	 * be terminated with CHECK CONDITION status, with the sense key set to
3517 	 * ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3518 	 * IN PARAMETER LIST.
3519 	 */
3520 	pr_reg_nacl = pr_reg->pr_reg_nacl;
3521 	matching_iname = (!strcmp(initiator_str,
3522 				  pr_reg_nacl->initiatorname)) ? 1 : 0;
3523 	if (!matching_iname)
3524 		goto after_iport_check;
3525 
3526 	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3527 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3528 			" matches: %s on received I_T Nexus\n", initiator_str,
3529 			pr_reg_nacl->initiatorname);
3530 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3531 		ret = -EINVAL;
3532 		goto out;
3533 	}
3534 	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3535 		pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3536 			" matches: %s %s on received I_T Nexus\n",
3537 			initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3538 			pr_reg->pr_reg_isid);
3539 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3540 		ret = -EINVAL;
3541 		goto out;
3542 	}
3543 after_iport_check:
3544 	/*
3545 	 * Locate the destination struct se_node_acl from the received Transport ID
3546 	 */
3547 	spin_lock_irq(&dest_se_tpg->acl_node_lock);
3548 	dest_node_acl = __core_tpg_get_initiator_node_acl(dest_se_tpg,
3549 				initiator_str);
3550 	if (dest_node_acl) {
3551 		atomic_inc(&dest_node_acl->acl_pr_ref_count);
3552 		smp_mb__after_atomic_inc();
3553 	}
3554 	spin_unlock_irq(&dest_se_tpg->acl_node_lock);
3555 
3556 	if (!dest_node_acl) {
3557 		pr_err("Unable to locate %s dest_node_acl for"
3558 			" TransportID%s\n", dest_tf_ops->get_fabric_name(),
3559 			initiator_str);
3560 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3561 		ret = -EINVAL;
3562 		goto out;
3563 	}
3564 	ret = core_scsi3_nodeacl_depend_item(dest_node_acl);
3565 	if (ret != 0) {
3566 		pr_err("core_scsi3_nodeacl_depend_item() for"
3567 			" dest_node_acl\n");
3568 		atomic_dec(&dest_node_acl->acl_pr_ref_count);
3569 		smp_mb__after_atomic_dec();
3570 		dest_node_acl = NULL;
3571 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3572 		ret = -EINVAL;
3573 		goto out;
3574 	}
3575 #if 0
3576 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3577 		" %s from TransportID\n", dest_tf_ops->get_fabric_name(),
3578 		dest_node_acl->initiatorname);
3579 #endif
3580 	/*
3581 	 * Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3582 	 * PORT IDENTIFIER.
3583 	 */
3584 	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3585 	if (!dest_se_deve) {
3586 		pr_err("Unable to locate %s dest_se_deve from RTPI:"
3587 			" %hu\n",  dest_tf_ops->get_fabric_name(), rtpi);
3588 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3589 		ret = -EINVAL;
3590 		goto out;
3591 	}
3592 
3593 	ret = core_scsi3_lunacl_depend_item(dest_se_deve);
3594 	if (ret < 0) {
3595 		pr_err("core_scsi3_lunacl_depend_item() failed\n");
3596 		atomic_dec(&dest_se_deve->pr_ref_count);
3597 		smp_mb__after_atomic_dec();
3598 		dest_se_deve = NULL;
3599 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3600 		ret = -EINVAL;
3601 		goto out;
3602 	}
3603 #if 0
3604 	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3605 		" ACL for dest_se_deve->mapped_lun: %u\n",
3606 		dest_tf_ops->get_fabric_name(), dest_node_acl->initiatorname,
3607 		dest_se_deve->mapped_lun);
3608 #endif
3609 	/*
3610 	 * A persistent reservation needs to already existing in order to
3611 	 * successfully complete the REGISTER_AND_MOVE service action..
3612 	 */
3613 	spin_lock(&dev->dev_reservation_lock);
3614 	pr_res_holder = dev->dev_pr_res_holder;
3615 	if (!pr_res_holder) {
3616 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3617 			" currently held\n");
3618 		spin_unlock(&dev->dev_reservation_lock);
3619 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3620 		ret = -EINVAL;
3621 		goto out;
3622 	}
3623 	/*
3624 	 * The received on I_T Nexus must be the reservation holder.
3625 	 *
3626 	 * From spc4r17 section 5.7.8  Table 50 --
3627 	 * 	Register behaviors for a REGISTER AND MOVE service action
3628 	 */
3629 	if (pr_res_holder != pr_reg) {
3630 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3631 			" Nexus is not reservation holder\n");
3632 		spin_unlock(&dev->dev_reservation_lock);
3633 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3634 		ret = -EINVAL;
3635 		goto out;
3636 	}
3637 	/*
3638 	 * From spc4r17 section 5.7.8: registering and moving reservation
3639 	 *
3640 	 * If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3641 	 * action is received and the established persistent reservation is a
3642 	 * Write Exclusive - All Registrants type or Exclusive Access -
3643 	 * All Registrants type reservation, then the command shall be completed
3644 	 * with RESERVATION CONFLICT status.
3645 	 */
3646 	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3647 	    (pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3648 		pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3649 			" reservation for type: %s\n",
3650 			core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3651 		spin_unlock(&dev->dev_reservation_lock);
3652 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3653 		ret = -EINVAL;
3654 		goto out;
3655 	}
3656 	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3657 	/*
3658 	 * b) Ignore the contents of the (received) SCOPE and TYPE fields;
3659 	 */
3660 	type = pr_res_holder->pr_res_type;
3661 	scope = pr_res_holder->pr_res_type;
3662 	/*
3663 	 * c) Associate the reservation key specified in the SERVICE ACTION
3664 	 *    RESERVATION KEY field with the I_T nexus specified as the
3665 	 *    destination of the register and move, where:
3666 	 *    A) The I_T nexus is specified by the TransportID and the
3667 	 *	 RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3668 	 *    B) Regardless of the TransportID format used, the association for
3669 	 *       the initiator port is based on either the initiator port name
3670 	 *       (see 3.1.71) on SCSI transport protocols where port names are
3671 	 *       required or the initiator port identifier (see 3.1.70) on SCSI
3672 	 *       transport protocols where port names are not required;
3673 	 * d) Register the reservation key specified in the SERVICE ACTION
3674 	 *    RESERVATION KEY field;
3675 	 * e) Retain the reservation key specified in the SERVICE ACTION
3676 	 *    RESERVATION KEY field and associated information;
3677 	 *
3678 	 * Also, It is not an error for a REGISTER AND MOVE service action to
3679 	 * register an I_T nexus that is already registered with the same
3680 	 * reservation key or a different reservation key.
3681 	 */
3682 	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3683 					iport_ptr);
3684 	if (!dest_pr_reg) {
3685 		ret = core_scsi3_alloc_registration(cmd->se_dev,
3686 				dest_node_acl, dest_se_deve, iport_ptr,
3687 				sa_res_key, 0, aptpl, 2, 1);
3688 		if (ret != 0) {
3689 			spin_unlock(&dev->dev_reservation_lock);
3690 			cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3691 			ret = -EINVAL;
3692 			goto out;
3693 		}
3694 		dest_pr_reg = __core_scsi3_locate_pr_reg(dev, dest_node_acl,
3695 						iport_ptr);
3696 		new_reg = 1;
3697 	}
3698 	/*
3699 	 * f) Release the persistent reservation for the persistent reservation
3700 	 *    holder (i.e., the I_T nexus on which the
3701 	 */
3702 	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
3703 			dev->dev_pr_res_holder, 0);
3704 	/*
3705 	 * g) Move the persistent reservation to the specified I_T nexus using
3706 	 *    the same scope and type as the persistent reservation released in
3707 	 *    item f); and
3708 	 */
3709 	dev->dev_pr_res_holder = dest_pr_reg;
3710 	dest_pr_reg->pr_res_holder = 1;
3711 	dest_pr_reg->pr_res_type = type;
3712 	pr_reg->pr_res_scope = scope;
3713 	prf_isid = core_pr_dump_initiator_port(pr_reg, &i_buf[0],
3714 				PR_REG_ISID_ID_LEN);
3715 	/*
3716 	 * Increment PRGeneration for existing registrations..
3717 	 */
3718 	if (!new_reg)
3719 		dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3720 	spin_unlock(&dev->dev_reservation_lock);
3721 
3722 	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3723 		" created new reservation holder TYPE: %s on object RTPI:"
3724 		" %hu  PRGeneration: 0x%08x\n", dest_tf_ops->get_fabric_name(),
3725 		core_scsi3_pr_dump_type(type), rtpi,
3726 		dest_pr_reg->pr_res_generation);
3727 	pr_debug("SPC-3 PR Successfully moved reservation from"
3728 		" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3729 		tf_ops->get_fabric_name(), pr_reg_nacl->initiatorname,
3730 		(prf_isid) ? &i_buf[0] : "", dest_tf_ops->get_fabric_name(),
3731 		dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3732 		iport_ptr : "");
3733 	/*
3734 	 * It is now safe to release configfs group dependencies for destination
3735 	 * of Transport ID Initiator Device/Port Identifier
3736 	 */
3737 	core_scsi3_lunacl_undepend_item(dest_se_deve);
3738 	core_scsi3_nodeacl_undepend_item(dest_node_acl);
3739 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3740 	/*
3741 	 * h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3742 	 * nexus on which PERSISTENT RESERVE OUT command was received.
3743 	 */
3744 	if (unreg) {
3745 		spin_lock(&pr_tmpl->registration_lock);
3746 		__core_scsi3_free_registration(dev, pr_reg, NULL, 1);
3747 		spin_unlock(&pr_tmpl->registration_lock);
3748 	} else
3749 		core_scsi3_put_pr_reg(pr_reg);
3750 
3751 	/*
3752 	 * Clear the APTPL metadata if APTPL has been disabled, otherwise
3753 	 * write out the updated metadata to struct file for this SCSI device.
3754 	 */
3755 	if (!aptpl) {
3756 		pr_tmpl->pr_aptpl_active = 0;
3757 		core_scsi3_update_and_write_aptpl(cmd->se_dev, NULL, 0);
3758 		pr_debug("SPC-3 PR: Set APTPL Bit Deactivated for"
3759 				" REGISTER_AND_MOVE\n");
3760 	} else {
3761 		pr_tmpl->pr_aptpl_active = 1;
3762 		ret = core_scsi3_update_and_write_aptpl(cmd->se_dev,
3763 				&dest_pr_reg->pr_aptpl_buf[0],
3764 				pr_tmpl->pr_aptpl_buf_len);
3765 		if (!ret)
3766 			pr_debug("SPC-3 PR: Set APTPL Bit Activated for"
3767 					" REGISTER_AND_MOVE\n");
3768 	}
3769 
3770 	transport_kunmap_data_sg(cmd);
3771 
3772 	core_scsi3_put_pr_reg(dest_pr_reg);
3773 	return 0;
3774 out:
3775 	if (buf)
3776 		transport_kunmap_data_sg(cmd);
3777 	if (dest_se_deve)
3778 		core_scsi3_lunacl_undepend_item(dest_se_deve);
3779 	if (dest_node_acl)
3780 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
3781 	core_scsi3_tpg_undepend_item(dest_se_tpg);
3782 	core_scsi3_put_pr_reg(pr_reg);
3783 	return ret;
3784 }
3785 
3786 static unsigned long long core_scsi3_extract_reservation_key(unsigned char *cdb)
3787 {
3788 	unsigned int __v1, __v2;
3789 
3790 	__v1 = (cdb[0] << 24) | (cdb[1] << 16) | (cdb[2] << 8) | cdb[3];
3791 	__v2 = (cdb[4] << 24) | (cdb[5] << 16) | (cdb[6] << 8) | cdb[7];
3792 
3793 	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
3794 }
3795 
3796 /*
3797  * See spc4r17 section 6.14 Table 170
3798  */
3799 int target_scsi3_emulate_pr_out(struct se_task *task)
3800 {
3801 	struct se_cmd *cmd = task->task_se_cmd;
3802 	unsigned char *cdb = &cmd->t_task_cdb[0];
3803 	unsigned char *buf;
3804 	u64 res_key, sa_res_key;
3805 	int sa, scope, type, aptpl;
3806 	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3807 	int ret;
3808 
3809 	/*
3810 	 * Following spc2r20 5.5.1 Reservations overview:
3811 	 *
3812 	 * If a logical unit has been reserved by any RESERVE command and is
3813 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
3814 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
3815 	 * initiator or service action and shall terminate with a RESERVATION
3816 	 * CONFLICT status.
3817 	 */
3818 	if (cmd->se_dev->dev_flags & DF_SPC2_RESERVATIONS) {
3819 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3820 			" SPC-2 reservation is held, returning"
3821 			" RESERVATION_CONFLICT\n");
3822 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
3823 		ret = EINVAL;
3824 		goto out;
3825 	}
3826 
3827 	/*
3828 	 * FIXME: A NULL struct se_session pointer means an this is not coming from
3829 	 * a $FABRIC_MOD's nexus, but from internal passthrough ops.
3830 	 */
3831 	if (!cmd->se_sess) {
3832 		cmd->scsi_sense_reason = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3833 		return -EINVAL;
3834 	}
3835 
3836 	if (cmd->data_length < 24) {
3837 		pr_warn("SPC-PR: Received PR OUT parameter list"
3838 			" length too small: %u\n", cmd->data_length);
3839 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3840 		ret = -EINVAL;
3841 		goto out;
3842 	}
3843 	/*
3844 	 * From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3845 	 */
3846 	sa = (cdb[1] & 0x1f);
3847 	scope = (cdb[2] & 0xf0);
3848 	type = (cdb[2] & 0x0f);
3849 
3850 	buf = transport_kmap_data_sg(cmd);
3851 	/*
3852 	 * From PERSISTENT_RESERVE_OUT parameter list (payload)
3853 	 */
3854 	res_key = core_scsi3_extract_reservation_key(&buf[0]);
3855 	sa_res_key = core_scsi3_extract_reservation_key(&buf[8]);
3856 	/*
3857 	 * REGISTER_AND_MOVE uses a different SA parameter list containing
3858 	 * SCSI TransportIDs.
3859 	 */
3860 	if (sa != PRO_REGISTER_AND_MOVE) {
3861 		spec_i_pt = (buf[20] & 0x08);
3862 		all_tg_pt = (buf[20] & 0x04);
3863 		aptpl = (buf[20] & 0x01);
3864 	} else {
3865 		aptpl = (buf[17] & 0x01);
3866 		unreg = (buf[17] & 0x02);
3867 	}
3868 	transport_kunmap_data_sg(cmd);
3869 	buf = NULL;
3870 
3871 	/*
3872 	 * SPEC_I_PT=1 is only valid for Service action: REGISTER
3873 	 */
3874 	if (spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER)) {
3875 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3876 		ret = -EINVAL;
3877 		goto out;
3878 	}
3879 
3880 	/*
3881 	 * From spc4r17 section 6.14:
3882 	 *
3883 	 * If the SPEC_I_PT bit is set to zero, the service action is not
3884 	 * REGISTER AND MOVE, and the parameter list length is not 24, then
3885 	 * the command shall be terminated with CHECK CONDITION status, with
3886 	 * the sense key set to ILLEGAL REQUEST, and the additional sense
3887 	 * code set to PARAMETER LIST LENGTH ERROR.
3888 	 */
3889 	if (!spec_i_pt && ((cdb[1] & 0x1f) != PRO_REGISTER_AND_MOVE) &&
3890 	    (cmd->data_length != 24)) {
3891 		pr_warn("SPC-PR: Received PR OUT illegal parameter"
3892 			" list length: %u\n", cmd->data_length);
3893 		cmd->scsi_sense_reason = TCM_INVALID_PARAMETER_LIST;
3894 		ret = -EINVAL;
3895 		goto out;
3896 	}
3897 	/*
3898 	 * (core_scsi3_emulate_pro_* function parameters
3899 	 * are defined by spc4r17 Table 174:
3900 	 * PERSISTENT_RESERVE_OUT service actions and valid parameters.
3901 	 */
3902 	switch (sa) {
3903 	case PRO_REGISTER:
3904 		ret = core_scsi3_emulate_pro_register(cmd,
3905 			res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, 0);
3906 		break;
3907 	case PRO_RESERVE:
3908 		ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3909 		break;
3910 	case PRO_RELEASE:
3911 		ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3912 		break;
3913 	case PRO_CLEAR:
3914 		ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3915 		break;
3916 	case PRO_PREEMPT:
3917 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3918 					res_key, sa_res_key, 0);
3919 		break;
3920 	case PRO_PREEMPT_AND_ABORT:
3921 		ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3922 					res_key, sa_res_key, 1);
3923 		break;
3924 	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3925 		ret = core_scsi3_emulate_pro_register(cmd,
3926 			0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, 1);
3927 		break;
3928 	case PRO_REGISTER_AND_MOVE:
3929 		ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3930 				sa_res_key, aptpl, unreg);
3931 		break;
3932 	default:
3933 		pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3934 			" action: 0x%02x\n", cdb[1] & 0x1f);
3935 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3936 		ret = -EINVAL;
3937 		break;
3938 	}
3939 
3940 out:
3941 	if (!ret) {
3942 		task->task_scsi_status = GOOD;
3943 		transport_complete_task(task, 1);
3944 	}
3945 	return ret;
3946 }
3947 
3948 /*
3949  * PERSISTENT_RESERVE_IN Service Action READ_KEYS
3950  *
3951  * See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3952  */
3953 static int core_scsi3_pri_read_keys(struct se_cmd *cmd)
3954 {
3955 	struct se_device *se_dev = cmd->se_dev;
3956 	struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
3957 	struct t10_pr_registration *pr_reg;
3958 	unsigned char *buf;
3959 	u32 add_len = 0, off = 8;
3960 
3961 	if (cmd->data_length < 8) {
3962 		pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3963 			" too small\n", cmd->data_length);
3964 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
3965 		return -EINVAL;
3966 	}
3967 
3968 	buf = transport_kmap_data_sg(cmd);
3969 	buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
3970 	buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
3971 	buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
3972 	buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
3973 
3974 	spin_lock(&su_dev->t10_pr.registration_lock);
3975 	list_for_each_entry(pr_reg, &su_dev->t10_pr.registration_list,
3976 			pr_reg_list) {
3977 		/*
3978 		 * Check for overflow of 8byte PRI READ_KEYS payload and
3979 		 * next reservation key list descriptor.
3980 		 */
3981 		if ((add_len + 8) > (cmd->data_length - 8))
3982 			break;
3983 
3984 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
3985 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
3986 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
3987 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
3988 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
3989 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
3990 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
3991 		buf[off++] = (pr_reg->pr_res_key & 0xff);
3992 
3993 		add_len += 8;
3994 	}
3995 	spin_unlock(&su_dev->t10_pr.registration_lock);
3996 
3997 	buf[4] = ((add_len >> 24) & 0xff);
3998 	buf[5] = ((add_len >> 16) & 0xff);
3999 	buf[6] = ((add_len >> 8) & 0xff);
4000 	buf[7] = (add_len & 0xff);
4001 
4002 	transport_kunmap_data_sg(cmd);
4003 
4004 	return 0;
4005 }
4006 
4007 /*
4008  * PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
4009  *
4010  * See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
4011  */
4012 static int core_scsi3_pri_read_reservation(struct se_cmd *cmd)
4013 {
4014 	struct se_device *se_dev = cmd->se_dev;
4015 	struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
4016 	struct t10_pr_registration *pr_reg;
4017 	unsigned char *buf;
4018 	u64 pr_res_key;
4019 	u32 add_len = 16; /* Hardcoded to 16 when a reservation is held. */
4020 
4021 	if (cmd->data_length < 8) {
4022 		pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
4023 			" too small\n", cmd->data_length);
4024 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4025 		return -EINVAL;
4026 	}
4027 
4028 	buf = transport_kmap_data_sg(cmd);
4029 	buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
4030 	buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
4031 	buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
4032 	buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
4033 
4034 	spin_lock(&se_dev->dev_reservation_lock);
4035 	pr_reg = se_dev->dev_pr_res_holder;
4036 	if ((pr_reg)) {
4037 		/*
4038 		 * Set the hardcoded Additional Length
4039 		 */
4040 		buf[4] = ((add_len >> 24) & 0xff);
4041 		buf[5] = ((add_len >> 16) & 0xff);
4042 		buf[6] = ((add_len >> 8) & 0xff);
4043 		buf[7] = (add_len & 0xff);
4044 
4045 		if (cmd->data_length < 22)
4046 			goto err;
4047 
4048 		/*
4049 		 * Set the Reservation key.
4050 		 *
4051 		 * From spc4r17, section 5.7.10:
4052 		 * A persistent reservation holder has its reservation key
4053 		 * returned in the parameter data from a PERSISTENT
4054 		 * RESERVE IN command with READ RESERVATION service action as
4055 		 * follows:
4056 		 * a) For a persistent reservation of the type Write Exclusive
4057 		 *    - All Registrants or Exclusive Access ­ All Regitrants,
4058 		 *      the reservation key shall be set to zero; or
4059 		 * b) For all other persistent reservation types, the
4060 		 *    reservation key shall be set to the registered
4061 		 *    reservation key for the I_T nexus that holds the
4062 		 *    persistent reservation.
4063 		 */
4064 		if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
4065 		    (pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
4066 			pr_res_key = 0;
4067 		else
4068 			pr_res_key = pr_reg->pr_res_key;
4069 
4070 		buf[8] = ((pr_res_key >> 56) & 0xff);
4071 		buf[9] = ((pr_res_key >> 48) & 0xff);
4072 		buf[10] = ((pr_res_key >> 40) & 0xff);
4073 		buf[11] = ((pr_res_key >> 32) & 0xff);
4074 		buf[12] = ((pr_res_key >> 24) & 0xff);
4075 		buf[13] = ((pr_res_key >> 16) & 0xff);
4076 		buf[14] = ((pr_res_key >> 8) & 0xff);
4077 		buf[15] = (pr_res_key & 0xff);
4078 		/*
4079 		 * Set the SCOPE and TYPE
4080 		 */
4081 		buf[21] = (pr_reg->pr_res_scope & 0xf0) |
4082 			  (pr_reg->pr_res_type & 0x0f);
4083 	}
4084 
4085 err:
4086 	spin_unlock(&se_dev->dev_reservation_lock);
4087 	transport_kunmap_data_sg(cmd);
4088 
4089 	return 0;
4090 }
4091 
4092 /*
4093  * PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
4094  *
4095  * See spc4r17 section 6.13.4 Table 165
4096  */
4097 static int core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
4098 {
4099 	struct se_device *dev = cmd->se_dev;
4100 	struct t10_reservation *pr_tmpl = &dev->se_sub_dev->t10_pr;
4101 	unsigned char *buf;
4102 	u16 add_len = 8; /* Hardcoded to 8. */
4103 
4104 	if (cmd->data_length < 6) {
4105 		pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
4106 			" %u too small\n", cmd->data_length);
4107 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4108 		return -EINVAL;
4109 	}
4110 
4111 	buf = transport_kmap_data_sg(cmd);
4112 
4113 	buf[0] = ((add_len << 8) & 0xff);
4114 	buf[1] = (add_len & 0xff);
4115 	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
4116 	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
4117 	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
4118 	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
4119 	/*
4120 	 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
4121 	 * set the TMV: Task Mask Valid bit.
4122 	 */
4123 	buf[3] |= 0x80;
4124 	/*
4125 	 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
4126 	 */
4127 	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
4128 	/*
4129 	 * PTPL_A: Persistence across Target Power Loss Active bit
4130 	 */
4131 	if (pr_tmpl->pr_aptpl_active)
4132 		buf[3] |= 0x01;
4133 	/*
4134 	 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
4135 	 */
4136 	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
4137 	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
4138 	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
4139 	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
4140 	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
4141 	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
4142 
4143 	transport_kunmap_data_sg(cmd);
4144 
4145 	return 0;
4146 }
4147 
4148 /*
4149  * PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
4150  *
4151  * See spc4r17 section 6.13.5 Table 168 and 169
4152  */
4153 static int core_scsi3_pri_read_full_status(struct se_cmd *cmd)
4154 {
4155 	struct se_device *se_dev = cmd->se_dev;
4156 	struct se_node_acl *se_nacl;
4157 	struct se_subsystem_dev *su_dev = se_dev->se_sub_dev;
4158 	struct se_portal_group *se_tpg;
4159 	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
4160 	struct t10_reservation *pr_tmpl = &se_dev->se_sub_dev->t10_pr;
4161 	unsigned char *buf;
4162 	u32 add_desc_len = 0, add_len = 0, desc_len, exp_desc_len;
4163 	u32 off = 8; /* off into first Full Status descriptor */
4164 	int format_code = 0;
4165 
4166 	if (cmd->data_length < 8) {
4167 		pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
4168 			" too small\n", cmd->data_length);
4169 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4170 		return -EINVAL;
4171 	}
4172 
4173 	buf = transport_kmap_data_sg(cmd);
4174 
4175 	buf[0] = ((su_dev->t10_pr.pr_generation >> 24) & 0xff);
4176 	buf[1] = ((su_dev->t10_pr.pr_generation >> 16) & 0xff);
4177 	buf[2] = ((su_dev->t10_pr.pr_generation >> 8) & 0xff);
4178 	buf[3] = (su_dev->t10_pr.pr_generation & 0xff);
4179 
4180 	spin_lock(&pr_tmpl->registration_lock);
4181 	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
4182 			&pr_tmpl->registration_list, pr_reg_list) {
4183 
4184 		se_nacl = pr_reg->pr_reg_nacl;
4185 		se_tpg = pr_reg->pr_reg_nacl->se_tpg;
4186 		add_desc_len = 0;
4187 
4188 		atomic_inc(&pr_reg->pr_res_holders);
4189 		smp_mb__after_atomic_inc();
4190 		spin_unlock(&pr_tmpl->registration_lock);
4191 		/*
4192 		 * Determine expected length of $FABRIC_MOD specific
4193 		 * TransportID full status descriptor..
4194 		 */
4195 		exp_desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id_len(
4196 				se_tpg, se_nacl, pr_reg, &format_code);
4197 
4198 		if ((exp_desc_len + add_len) > cmd->data_length) {
4199 			pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
4200 				" out of buffer: %d\n", cmd->data_length);
4201 			spin_lock(&pr_tmpl->registration_lock);
4202 			atomic_dec(&pr_reg->pr_res_holders);
4203 			smp_mb__after_atomic_dec();
4204 			break;
4205 		}
4206 		/*
4207 		 * Set RESERVATION KEY
4208 		 */
4209 		buf[off++] = ((pr_reg->pr_res_key >> 56) & 0xff);
4210 		buf[off++] = ((pr_reg->pr_res_key >> 48) & 0xff);
4211 		buf[off++] = ((pr_reg->pr_res_key >> 40) & 0xff);
4212 		buf[off++] = ((pr_reg->pr_res_key >> 32) & 0xff);
4213 		buf[off++] = ((pr_reg->pr_res_key >> 24) & 0xff);
4214 		buf[off++] = ((pr_reg->pr_res_key >> 16) & 0xff);
4215 		buf[off++] = ((pr_reg->pr_res_key >> 8) & 0xff);
4216 		buf[off++] = (pr_reg->pr_res_key & 0xff);
4217 		off += 4; /* Skip Over Reserved area */
4218 
4219 		/*
4220 		 * Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
4221 		 */
4222 		if (pr_reg->pr_reg_all_tg_pt)
4223 			buf[off] = 0x02;
4224 		/*
4225 		 * The struct se_lun pointer will be present for the
4226 		 * reservation holder for PR_HOLDER bit.
4227 		 *
4228 		 * Also, if this registration is the reservation
4229 		 * holder, fill in SCOPE and TYPE in the next byte.
4230 		 */
4231 		if (pr_reg->pr_res_holder) {
4232 			buf[off++] |= 0x01;
4233 			buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
4234 				     (pr_reg->pr_res_type & 0x0f);
4235 		} else
4236 			off += 2;
4237 
4238 		off += 4; /* Skip over reserved area */
4239 		/*
4240 		 * From spc4r17 6.3.15:
4241 		 *
4242 		 * If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
4243 		 * IDENTIFIER field contains the relative port identifier (see
4244 		 * 3.1.120) of the target port that is part of the I_T nexus
4245 		 * described by this full status descriptor. If the ALL_TG_PT
4246 		 * bit is set to one, the contents of the RELATIVE TARGET PORT
4247 		 * IDENTIFIER field are not defined by this standard.
4248 		 */
4249 		if (!pr_reg->pr_reg_all_tg_pt) {
4250 			struct se_port *port = pr_reg->pr_reg_tg_pt_lun->lun_sep;
4251 
4252 			buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
4253 			buf[off++] = (port->sep_rtpi & 0xff);
4254 		} else
4255 			off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFER */
4256 
4257 		/*
4258 		 * Now, have the $FABRIC_MOD fill in the protocol identifier
4259 		 */
4260 		desc_len = se_tpg->se_tpg_tfo->tpg_get_pr_transport_id(se_tpg,
4261 				se_nacl, pr_reg, &format_code, &buf[off+4]);
4262 
4263 		spin_lock(&pr_tmpl->registration_lock);
4264 		atomic_dec(&pr_reg->pr_res_holders);
4265 		smp_mb__after_atomic_dec();
4266 		/*
4267 		 * Set the ADDITIONAL DESCRIPTOR LENGTH
4268 		 */
4269 		buf[off++] = ((desc_len >> 24) & 0xff);
4270 		buf[off++] = ((desc_len >> 16) & 0xff);
4271 		buf[off++] = ((desc_len >> 8) & 0xff);
4272 		buf[off++] = (desc_len & 0xff);
4273 		/*
4274 		 * Size of full desctipor header minus TransportID
4275 		 * containing $FABRIC_MOD specific) initiator device/port
4276 		 * WWN information.
4277 		 *
4278 		 *  See spc4r17 Section 6.13.5 Table 169
4279 		 */
4280 		add_desc_len = (24 + desc_len);
4281 
4282 		off += desc_len;
4283 		add_len += add_desc_len;
4284 	}
4285 	spin_unlock(&pr_tmpl->registration_lock);
4286 	/*
4287 	 * Set ADDITIONAL_LENGTH
4288 	 */
4289 	buf[4] = ((add_len >> 24) & 0xff);
4290 	buf[5] = ((add_len >> 16) & 0xff);
4291 	buf[6] = ((add_len >> 8) & 0xff);
4292 	buf[7] = (add_len & 0xff);
4293 
4294 	transport_kunmap_data_sg(cmd);
4295 
4296 	return 0;
4297 }
4298 
4299 int target_scsi3_emulate_pr_in(struct se_task *task)
4300 {
4301 	struct se_cmd *cmd = task->task_se_cmd;
4302 	int ret;
4303 
4304 	/*
4305 	 * Following spc2r20 5.5.1 Reservations overview:
4306 	 *
4307 	 * If a logical unit has been reserved by any RESERVE command and is
4308 	 * still reserved by any initiator, all PERSISTENT RESERVE IN and all
4309 	 * PERSISTENT RESERVE OUT commands shall conflict regardless of
4310 	 * initiator or service action and shall terminate with a RESERVATION
4311 	 * CONFLICT status.
4312 	 */
4313 	if (cmd->se_dev->dev_flags & DF_SPC2_RESERVATIONS) {
4314 		pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4315 			" SPC-2 reservation is held, returning"
4316 			" RESERVATION_CONFLICT\n");
4317 		cmd->scsi_sense_reason = TCM_RESERVATION_CONFLICT;
4318 		return -EINVAL;
4319 	}
4320 
4321 	switch (cmd->t_task_cdb[1] & 0x1f) {
4322 	case PRI_READ_KEYS:
4323 		ret = core_scsi3_pri_read_keys(cmd);
4324 		break;
4325 	case PRI_READ_RESERVATION:
4326 		ret = core_scsi3_pri_read_reservation(cmd);
4327 		break;
4328 	case PRI_REPORT_CAPABILITIES:
4329 		ret = core_scsi3_pri_report_capabilities(cmd);
4330 		break;
4331 	case PRI_READ_FULL_STATUS:
4332 		ret = core_scsi3_pri_read_full_status(cmd);
4333 		break;
4334 	default:
4335 		pr_err("Unknown PERSISTENT_RESERVE_IN service"
4336 			" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4337 		cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
4338 		ret = -EINVAL;
4339 		break;
4340 	}
4341 
4342 	if (!ret) {
4343 		task->task_scsi_status = GOOD;
4344 		transport_complete_task(task, 1);
4345 	}
4346 	return ret;
4347 }
4348 
4349 static int core_pt_reservation_check(struct se_cmd *cmd, u32 *pr_res_type)
4350 {
4351 	return 0;
4352 }
4353 
4354 static int core_pt_seq_non_holder(
4355 	struct se_cmd *cmd,
4356 	unsigned char *cdb,
4357 	u32 pr_reg_type)
4358 {
4359 	return 0;
4360 }
4361 
4362 int core_setup_reservations(struct se_device *dev, int force_pt)
4363 {
4364 	struct se_subsystem_dev *su_dev = dev->se_sub_dev;
4365 	struct t10_reservation *rest = &su_dev->t10_pr;
4366 	/*
4367 	 * If this device is from Target_Core_Mod/pSCSI, use the reservations
4368 	 * of the Underlying SCSI hardware.  In Linux/SCSI terms, this can
4369 	 * cause a problem because libata and some SATA RAID HBAs appear
4370 	 * under Linux/SCSI, but to emulate reservations themselves.
4371 	 */
4372 	if (((dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
4373 	    !(dev->se_sub_dev->se_dev_attrib.emulate_reservations)) || force_pt) {
4374 		rest->res_type = SPC_PASSTHROUGH;
4375 		rest->pr_ops.t10_reservation_check = &core_pt_reservation_check;
4376 		rest->pr_ops.t10_seq_non_holder = &core_pt_seq_non_holder;
4377 		pr_debug("%s: Using SPC_PASSTHROUGH, no reservation"
4378 			" emulation\n", dev->transport->name);
4379 		return 0;
4380 	}
4381 	/*
4382 	 * If SPC-3 or above is reported by real or emulated struct se_device,
4383 	 * use emulated Persistent Reservations.
4384 	 */
4385 	if (dev->transport->get_device_rev(dev) >= SCSI_3) {
4386 		rest->res_type = SPC3_PERSISTENT_RESERVATIONS;
4387 		rest->pr_ops.t10_reservation_check = &core_scsi3_pr_reservation_check;
4388 		rest->pr_ops.t10_seq_non_holder = &core_scsi3_pr_seq_non_holder;
4389 		pr_debug("%s: Using SPC3_PERSISTENT_RESERVATIONS"
4390 			" emulation\n", dev->transport->name);
4391 	} else {
4392 		rest->res_type = SPC2_RESERVATIONS;
4393 		rest->pr_ops.t10_reservation_check = &core_scsi2_reservation_check;
4394 		rest->pr_ops.t10_seq_non_holder =
4395 				&core_scsi2_reservation_seq_non_holder;
4396 		pr_debug("%s: Using SPC2_RESERVATIONS emulation\n",
4397 			dev->transport->name);
4398 	}
4399 
4400 	return 0;
4401 }
4402