1	// SPDX-License-Identifier: GPL-2.0-or-later
2	/*******************************************************************************
3	* Filename: target_core_pr.c
4	*
5	* This file contains SPC-3 compliant persistent reservations and
6	* legacy SPC-2 reservations with compatible reservation handling (CRH=1)
7	*
8	* (c) Copyright 2009-2013 Datera, Inc.
9	*
10	* Nicholas A. Bellinger <nab@kernel.org>
11	*
12	******************************************************************************/
13
14	#include <linux/slab.h>
15	#include <linux/spinlock.h>
16	#include <linux/list.h>
17	#include <linux/vmalloc.h>
18	#include <linux/file.h>
19	#include <linux/fcntl.h>
20	#include <linux/fs.h>
21	#include <scsi/scsi_proto.h>
22	#include <asm/unaligned.h>
23
24	#include <target/target_core_base.h>
25	#include <target/target_core_backend.h>
26	#include <target/target_core_fabric.h>
27
28	#include "target_core_internal.h"
29	#include "target_core_pr.h"
30	#include "target_core_ua.h"
31
32	/*
33	* Used for Specify Initiator Ports Capable Bit (SPEC_I_PT)
34	*/
35	struct pr_transport_id_holder {
36	struct t10_pr_registration *dest_pr_reg;
37	struct se_portal_group *dest_tpg;
38	struct se_node_acl *dest_node_acl;
39	struct se_dev_entry *dest_se_deve;
40	struct list_head dest_list;
41	};
42
43	void core_pr_dump_initiator_port(
44	struct t10_pr_registration *pr_reg,
45	char *buf,
46	u32 size)
47	{
48	if (!pr_reg->isid_present_at_reg) {
49	buf[0] = '\0';
50	return;
51	}
52
53	snprintf(buf, size, fmt: ",i,0x%s", pr_reg->pr_reg_isid);
54	}
55
56	enum register_type {
57	REGISTER,
58	REGISTER_AND_IGNORE_EXISTING_KEY,
59	REGISTER_AND_MOVE,
60	};
61
62	enum preempt_type {
63	PREEMPT,
64	PREEMPT_AND_ABORT,
65	};
66
67	static void __core_scsi3_complete_pro_release(struct se_device *, struct se_node_acl *,
68	struct t10_pr_registration *, int, int);
69
70	static int is_reservation_holder(
71	struct t10_pr_registration *pr_res_holder,
72	struct t10_pr_registration *pr_reg)
73	{
74	int pr_res_type;
75
76	if (pr_res_holder) {
77	pr_res_type = pr_res_holder->pr_res_type;
78
79	return pr_res_holder == pr_reg ||
80	pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
81	pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG;
82	}
83	return 0;
84	}
85
86	static sense_reason_t
87	target_scsi2_reservation_check(struct se_cmd *cmd)
88	{
89	struct se_device *dev = cmd->se_dev;
90	struct se_session *sess = cmd->se_sess;
91
92	switch (cmd->t_task_cdb[0]) {
93	case INQUIRY:
94	case RELEASE:
95	case RELEASE_10:
96	return 0;
97	default:
98	break;
99	}
100
101	if (!dev->reservation_holder || !sess)
102	return 0;
103
104	if (dev->reservation_holder->se_node_acl != sess->se_node_acl)
105	return TCM_RESERVATION_CONFLICT;
106
107	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
108	if (dev->dev_res_bin_isid != sess->sess_bin_isid)
109	return TCM_RESERVATION_CONFLICT;
110	}
111
112	return 0;
113	}
114
115	static struct t10_pr_registration *core_scsi3_locate_pr_reg(struct se_device *,
116	struct se_node_acl *, struct se_session *);
117	static void core_scsi3_put_pr_reg(struct t10_pr_registration *);
118
119	static int target_check_scsi2_reservation_conflict(struct se_cmd *cmd)
120	{
121	struct se_session *se_sess = cmd->se_sess;
122	struct se_device *dev = cmd->se_dev;
123	struct t10_pr_registration *pr_reg;
124	struct t10_reservation *pr_tmpl = &dev->t10_pr;
125	int conflict = 0;
126
127	pr_reg = core_scsi3_locate_pr_reg(cmd->se_dev, se_sess->se_node_acl,
128	se_sess);
129	if (pr_reg) {
130	/*
131	* From spc4r17 5.7.3 Exceptions to SPC-2 RESERVE and RELEASE
132	* behavior
133	*
134	* A RESERVE(6) or RESERVE(10) command shall complete with GOOD
135	* status, but no reservation shall be established and the
136	* persistent reservation shall not be changed, if the command
137	* is received from a) and b) below.
138	*
139	* A RELEASE(6) or RELEASE(10) command shall complete with GOOD
140	* status, but the persistent reservation shall not be released,
141	* if the command is received from a) and b)
142	*
143	* a) An I_T nexus that is a persistent reservation holder; or
144	* b) An I_T nexus that is registered if a registrants only or
145	* all registrants type persistent reservation is present.
146	*
147	* In all other cases, a RESERVE(6) command, RESERVE(10) command,
148	* RELEASE(6) command, or RELEASE(10) command shall be processed
149	* as defined in SPC-2.
150	*/
151	if (pr_reg->pr_res_holder) {
152	core_scsi3_put_pr_reg(pr_reg);
153	return 1;
154	}
155	if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY) ||
156	(pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) ||
157	(pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
158	(pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
159	core_scsi3_put_pr_reg(pr_reg);
160	return 1;
161	}
162	core_scsi3_put_pr_reg(pr_reg);
163	conflict = 1;
164	} else {
165	/*
166	* Following spc2r20 5.5.1 Reservations overview:
167	*
168	* If a logical unit has executed a PERSISTENT RESERVE OUT
169	* command with the REGISTER or the REGISTER AND IGNORE
170	* EXISTING KEY service action and is still registered by any
171	* initiator, all RESERVE commands and all RELEASE commands
172	* regardless of initiator shall conflict and shall terminate
173	* with a RESERVATION CONFLICT status.
174	*/
175	spin_lock(lock: &pr_tmpl->registration_lock);
176	conflict = (list_empty(head: &pr_tmpl->registration_list)) ? 0 : 1;
177	spin_unlock(lock: &pr_tmpl->registration_lock);
178	}
179
180	if (conflict) {
181	pr_err("Received legacy SPC-2 RESERVE/RELEASE"
182	" while active SPC-3 registrations exist,"
183	" returning RESERVATION_CONFLICT\n");
184	return -EBUSY;
185	}
186
187	return 0;
188	}
189
190	void target_release_reservation(struct se_device *dev)
191	{
192	dev->reservation_holder = NULL;
193	dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS;
194	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS_WITH_ISID) {
195	dev->dev_res_bin_isid = 0;
196	dev->dev_reservation_flags &= ~DRF_SPC2_RESERVATIONS_WITH_ISID;
197	}
198	}
199
200	sense_reason_t
201	target_scsi2_reservation_release(struct se_cmd *cmd)
202	{
203	struct se_device *dev = cmd->se_dev;
204	struct se_session *sess = cmd->se_sess;
205	struct se_portal_group *tpg;
206	int rc;
207
208	if (!sess || !sess->se_tpg)
209	goto out;
210	rc = target_check_scsi2_reservation_conflict(cmd);
211	if (rc == 1)
212	goto out;
213	if (rc < 0)
214	return TCM_RESERVATION_CONFLICT;
215
216	spin_lock(lock: &dev->dev_reservation_lock);
217	if (!dev->reservation_holder || !sess)
218	goto out_unlock;
219
220	if (dev->reservation_holder->se_node_acl != sess->se_node_acl)
221	goto out_unlock;
222
223	if (dev->dev_res_bin_isid != sess->sess_bin_isid)
224	goto out_unlock;
225
226	target_release_reservation(dev);
227	tpg = sess->se_tpg;
228	pr_debug("SCSI-2 Released reservation for %s LUN: %llu ->"
229	" MAPPED LUN: %llu for %s\n",
230	tpg->se_tpg_tfo->fabric_name,
231	cmd->se_lun->unpacked_lun, cmd->orig_fe_lun,
232	sess->se_node_acl->initiatorname);
233
234	out_unlock:
235	spin_unlock(lock: &dev->dev_reservation_lock);
236	out:
237	target_complete_cmd(cmd, SAM_STAT_GOOD);
238	return 0;
239	}
240
241	sense_reason_t
242	target_scsi2_reservation_reserve(struct se_cmd *cmd)
243	{
244	struct se_device *dev = cmd->se_dev;
245	struct se_session *sess = cmd->se_sess;
246	struct se_portal_group *tpg;
247	sense_reason_t ret = 0;
248	int rc;
249
250	if ((cmd->t_task_cdb[1] & 0x01) &&
251	(cmd->t_task_cdb[1] & 0x02)) {
252	pr_err("LongIO and Obsolete Bits set, returning ILLEGAL_REQUEST\n");
253	return TCM_UNSUPPORTED_SCSI_OPCODE;
254	}
255	/*
256	* This is currently the case for target_core_mod passthrough struct se_cmd
257	* ops
258	*/
259	if (!sess || !sess->se_tpg)
260	goto out;
261	rc = target_check_scsi2_reservation_conflict(cmd);
262	if (rc == 1)
263	goto out;
264
265	if (rc < 0)
266	return TCM_RESERVATION_CONFLICT;
267
268	tpg = sess->se_tpg;
269	spin_lock(lock: &dev->dev_reservation_lock);
270	if (dev->reservation_holder &&
271	dev->reservation_holder->se_node_acl != sess->se_node_acl) {
272	pr_err("SCSI-2 RESERVATION CONFLICT for %s fabric\n",
273	tpg->se_tpg_tfo->fabric_name);
274	pr_err("Original reserver LUN: %llu %s\n",
275	cmd->se_lun->unpacked_lun,
276	dev->reservation_holder->se_node_acl->initiatorname);
277	pr_err("Current attempt - LUN: %llu -> MAPPED LUN: %llu"
278	" from %s \n", cmd->se_lun->unpacked_lun,
279	cmd->orig_fe_lun,
280	sess->se_node_acl->initiatorname);
281	ret = TCM_RESERVATION_CONFLICT;
282	goto out_unlock;
283	}
284
285	dev->reservation_holder = sess;
286	dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS;
287	if (sess->sess_bin_isid != 0) {
288	dev->dev_res_bin_isid = sess->sess_bin_isid;
289	dev->dev_reservation_flags |= DRF_SPC2_RESERVATIONS_WITH_ISID;
290	}
291	pr_debug("SCSI-2 Reserved %s LUN: %llu -> MAPPED LUN: %llu"
292	" for %s\n", tpg->se_tpg_tfo->fabric_name,
293	cmd->se_lun->unpacked_lun, cmd->orig_fe_lun,
294	sess->se_node_acl->initiatorname);
295
296	out_unlock:
297	spin_unlock(lock: &dev->dev_reservation_lock);
298	out:
299	if (!ret)
300	target_complete_cmd(cmd, SAM_STAT_GOOD);
301	return ret;
302	}
303
304
305	/*
306	* Begin SPC-3/SPC-4 Persistent Reservations emulation support
307	*
308	* This function is called by those initiator ports who are *NOT*
309	* the active PR reservation holder when a reservation is present.
310	*/
311	static int core_scsi3_pr_seq_non_holder(struct se_cmd *cmd, u32 pr_reg_type,
312	bool isid_mismatch)
313	{
314	unsigned char *cdb = cmd->t_task_cdb;
315	struct se_session *se_sess = cmd->se_sess;
316	struct se_node_acl *nacl = se_sess->se_node_acl;
317	int other_cdb = 0;
318	int registered_nexus = 0, ret = 1; /* Conflict by default */
319	int all_reg = 0, reg_only = 0; /* ALL_REG, REG_ONLY */
320	int we = 0; /* Write Exclusive */
321	int legacy = 0; /* Act like a legacy device and return
322	* RESERVATION CONFLICT on some CDBs */
323
324	if (isid_mismatch) {
325	registered_nexus = 0;
326	} else {
327	struct se_dev_entry *se_deve;
328
329	rcu_read_lock();
330	se_deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
331	if (se_deve)
332	registered_nexus = test_bit(DEF_PR_REG_ACTIVE,
333	&se_deve->deve_flags);
334	rcu_read_unlock();
335	}
336
337	switch (pr_reg_type) {
338	case PR_TYPE_WRITE_EXCLUSIVE:
339	we = 1;
340	fallthrough;
341	case PR_TYPE_EXCLUSIVE_ACCESS:
342	/*
343	* Some commands are only allowed for the persistent reservation
344	* holder.
345	*/
346	break;
347	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
348	we = 1;
349	fallthrough;
350	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
351	/*
352	* Some commands are only allowed for registered I_T Nexuses.
353	*/
354	reg_only = 1;
355	break;
356	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
357	we = 1;
358	fallthrough;
359	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
360	/*
361	* Each registered I_T Nexus is a reservation holder.
362	*/
363	all_reg = 1;
364	break;
365	default:
366	return -EINVAL;
367	}
368	/*
369	* Referenced from spc4r17 table 45 for *NON* PR holder access
370	*/
371	switch (cdb[0]) {
372	case SECURITY_PROTOCOL_IN:
373	if (registered_nexus)
374	return 0;
375	ret = (we) ? 0 : 1;
376	break;
377	case MODE_SENSE:
378	case MODE_SENSE_10:
379	case READ_ATTRIBUTE:
380	case READ_BUFFER:
381	case RECEIVE_DIAGNOSTIC:
382	if (legacy) {
383	ret = 1;
384	break;
385	}
386	if (registered_nexus) {
387	ret = 0;
388	break;
389	}
390	ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
391	break;
392	case PERSISTENT_RESERVE_OUT:
393	/*
394	* This follows PERSISTENT_RESERVE_OUT service actions that
395	* are allowed in the presence of various reservations.
396	* See spc4r17, table 46
397	*/
398	switch (cdb[1] & 0x1f) {
399	case PRO_CLEAR:
400	case PRO_PREEMPT:
401	case PRO_PREEMPT_AND_ABORT:
402	ret = (registered_nexus) ? 0 : 1;
403	break;
404	case PRO_REGISTER:
405	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
406	ret = 0;
407	break;
408	case PRO_REGISTER_AND_MOVE:
409	case PRO_RESERVE:
410	ret = 1;
411	break;
412	case PRO_RELEASE:
413	ret = (registered_nexus) ? 0 : 1;
414	break;
415	default:
416	pr_err("Unknown PERSISTENT_RESERVE_OUT service"
417	" action: 0x%02x\n", cdb[1] & 0x1f);
418	return -EINVAL;
419	}
420	break;
421	case RELEASE:
422	case RELEASE_10:
423	/* Handled by CRH=1 in target_scsi2_reservation_release() */
424	ret = 0;
425	break;
426	case RESERVE:
427	case RESERVE_10:
428	/* Handled by CRH=1 in target_scsi2_reservation_reserve() */
429	ret = 0;
430	break;
431	case TEST_UNIT_READY:
432	ret = (legacy) ? 1 : 0; /* Conflict for legacy */
433	break;
434	case MAINTENANCE_IN:
435	switch (cdb[1] & 0x1f) {
436	case MI_MANAGEMENT_PROTOCOL_IN:
437	if (registered_nexus) {
438	ret = 0;
439	break;
440	}
441	ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
442	break;
443	case MI_REPORT_SUPPORTED_OPERATION_CODES:
444	case MI_REPORT_SUPPORTED_TASK_MANAGEMENT_FUNCTIONS:
445	if (legacy) {
446	ret = 1;
447	break;
448	}
449	if (registered_nexus) {
450	ret = 0;
451	break;
452	}
453	ret = (we) ? 0 : 1; /* Allowed Write Exclusive */
454	break;
455	case MI_REPORT_ALIASES:
456	case MI_REPORT_IDENTIFYING_INFORMATION:
457	case MI_REPORT_PRIORITY:
458	case MI_REPORT_TARGET_PGS:
459	case MI_REPORT_TIMESTAMP:
460	ret = 0; /* Allowed */
461	break;
462	default:
463	pr_err("Unknown MI Service Action: 0x%02x\n",
464	(cdb[1] & 0x1f));
465	return -EINVAL;
466	}
467	break;
468	case ACCESS_CONTROL_IN:
469	case ACCESS_CONTROL_OUT:
470	case INQUIRY:
471	case LOG_SENSE:
472	case SERVICE_ACTION_IN_12:
473	case READ_CAPACITY:
474	case REPORT_LUNS:
475	case REQUEST_SENSE:
476	case PERSISTENT_RESERVE_IN:
477	ret = 0; /*/ Allowed CDBs */
478	break;
479	default:
480	other_cdb = 1;
481	break;
482	}
483	/*
484	* Case where the CDB is explicitly allowed in the above switch
485	* statement.
486	*/
487	if (!ret && !other_cdb) {
488	pr_debug("Allowing explicit CDB: 0x%02x for %s"
489	" reservation holder\n", cdb[0],
490	core_scsi3_pr_dump_type(pr_reg_type));
491
492	return ret;
493	}
494	/*
495	* Check if write exclusive initiator ports *NOT* holding the
496	* WRITE_EXCLUSIVE_* reservation.
497	*/
498	if (we && !registered_nexus) {
499	if (cmd->data_direction == DMA_TO_DEVICE) {
500	/*
501	* Conflict for write exclusive
502	*/
503	pr_debug("%s Conflict for unregistered nexus"
504	" %s CDB: 0x%02x to %s reservation\n",
505	transport_dump_cmd_direction(cmd),
506	se_sess->se_node_acl->initiatorname, cdb[0],
507	core_scsi3_pr_dump_type(pr_reg_type));
508	return 1;
509	} else {
510	/*
511	* Allow non WRITE CDBs for all Write Exclusive
512	* PR TYPEs to pass for registered and
513	* non-registered_nexuxes NOT holding the reservation.
514	*
515	* We only make noise for the unregisterd nexuses,
516	* as we expect registered non-reservation holding
517	* nexuses to issue CDBs.
518	*/
519
520	if (!registered_nexus) {
521	pr_debug("Allowing implicit CDB: 0x%02x"
522	" for %s reservation on unregistered"
523	" nexus\n", cdb[0],
524	core_scsi3_pr_dump_type(pr_reg_type));
525	}
526
527	return 0;
528	}
529	} else if ((reg_only) || (all_reg)) {
530	if (registered_nexus) {
531	/*
532	* For PR_*_REG_ONLY and PR_*_ALL_REG reservations,
533	* allow commands from registered nexuses.
534	*/
535
536	pr_debug("Allowing implicit CDB: 0x%02x for %s"
537	" reservation\n", cdb[0],
538	core_scsi3_pr_dump_type(pr_reg_type));
539
540	return 0;
541	}
542	} else if (we && registered_nexus) {
543	/*
544	* Reads are allowed for Write Exclusive locks
545	* from all registrants.
546	*/
547	if (cmd->data_direction == DMA_FROM_DEVICE) {
548	pr_debug("Allowing READ CDB: 0x%02x for %s"
549	" reservation\n", cdb[0],
550	core_scsi3_pr_dump_type(pr_reg_type));
551
552	return 0;
553	}
554	}
555	pr_debug("%s Conflict for %sregistered nexus %s CDB: 0x%2x"
556	" for %s reservation\n", transport_dump_cmd_direction(cmd),
557	(registered_nexus) ? "" : "un",
558	se_sess->se_node_acl->initiatorname, cdb[0],
559	core_scsi3_pr_dump_type(pr_reg_type));
560
561	return 1; /* Conflict by default */
562	}
563
564	static sense_reason_t
565	target_scsi3_pr_reservation_check(struct se_cmd *cmd)
566	{
567	struct se_device *dev = cmd->se_dev;
568	struct se_session *sess = cmd->se_sess;
569	u32 pr_reg_type;
570	bool isid_mismatch = false;
571
572	if (!dev->dev_pr_res_holder)
573	return 0;
574
575	pr_reg_type = dev->dev_pr_res_holder->pr_res_type;
576	cmd->pr_res_key = dev->dev_pr_res_holder->pr_res_key;
577	if (dev->dev_pr_res_holder->pr_reg_nacl != sess->se_node_acl)
578	goto check_nonholder;
579
580	if (dev->dev_pr_res_holder->isid_present_at_reg) {
581	if (dev->dev_pr_res_holder->pr_reg_bin_isid !=
582	sess->sess_bin_isid) {
583	isid_mismatch = true;
584	goto check_nonholder;
585	}
586	}
587
588	return 0;
589
590	check_nonholder:
591	if (core_scsi3_pr_seq_non_holder(cmd, pr_reg_type, isid_mismatch))
592	return TCM_RESERVATION_CONFLICT;
593	return 0;
594	}
595
596	static u32 core_scsi3_pr_generation(struct se_device *dev)
597	{
598	u32 prg;
599
600	/*
601	* PRGeneration field shall contain the value of a 32-bit wrapping
602	* counter mainted by the device server.
603	*
604	* Note that this is done regardless of Active Persist across
605	* Target PowerLoss (APTPL)
606	*
607	* See spc4r17 section 6.3.12 READ_KEYS service action
608	*/
609	spin_lock(lock: &dev->dev_reservation_lock);
610	prg = dev->t10_pr.pr_generation++;
611	spin_unlock(lock: &dev->dev_reservation_lock);
612
613	return prg;
614	}
615
616	static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
617	struct se_device *dev,
618	struct se_node_acl *nacl,
619	struct se_lun *lun,
620	struct se_dev_entry *dest_deve,
621	u64 mapped_lun,
622	unsigned char *isid,
623	u64 sa_res_key,
624	int all_tg_pt,
625	int aptpl)
626	{
627	struct t10_pr_registration *pr_reg;
628
629	pr_reg = kmem_cache_zalloc(k: t10_pr_reg_cache, GFP_ATOMIC);
630	if (!pr_reg) {
631	pr_err("Unable to allocate struct t10_pr_registration\n");
632	return NULL;
633	}
634
635	INIT_LIST_HEAD(list: &pr_reg->pr_reg_list);
636	INIT_LIST_HEAD(list: &pr_reg->pr_reg_abort_list);
637	INIT_LIST_HEAD(list: &pr_reg->pr_reg_aptpl_list);
638	INIT_LIST_HEAD(list: &pr_reg->pr_reg_atp_list);
639	INIT_LIST_HEAD(list: &pr_reg->pr_reg_atp_mem_list);
640	atomic_set(v: &pr_reg->pr_res_holders, i: 0);
641	pr_reg->pr_reg_nacl = nacl;
642	/*
643	* For destination registrations for ALL_TG_PT=1 and SPEC_I_PT=1,
644	* the se_dev_entry->pr_ref will have been already obtained by
645	* core_get_se_deve_from_rtpi() or __core_scsi3_alloc_registration().
646	*
647	* Otherwise, locate se_dev_entry now and obtain a reference until
648	* registration completes in __core_scsi3_add_registration().
649	*/
650	if (dest_deve) {
651	pr_reg->pr_reg_deve = dest_deve;
652	} else {
653	rcu_read_lock();
654	pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
655	if (!pr_reg->pr_reg_deve) {
656	rcu_read_unlock();
657	pr_err("Unable to locate PR deve %s mapped_lun: %llu\n",
658	nacl->initiatorname, mapped_lun);
659	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg);
660	return NULL;
661	}
662	kref_get(kref: &pr_reg->pr_reg_deve->pr_kref);
663	rcu_read_unlock();
664	}
665	pr_reg->pr_res_mapped_lun = mapped_lun;
666	pr_reg->pr_aptpl_target_lun = lun->unpacked_lun;
667	pr_reg->tg_pt_sep_rtpi = lun->lun_tpg->tpg_rtpi;
668	pr_reg->pr_res_key = sa_res_key;
669	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
670	pr_reg->pr_reg_aptpl = aptpl;
671	/*
672	* If an ISID value for this SCSI Initiator Port exists,
673	* save it to the registration now.
674	*/
675	if (isid != NULL) {
676	pr_reg->pr_reg_bin_isid = get_unaligned_be64(p: isid);
677	snprintf(buf: pr_reg->pr_reg_isid, PR_REG_ISID_LEN, fmt: "%s", isid);
678	pr_reg->isid_present_at_reg = 1;
679	}
680
681	return pr_reg;
682	}
683
684	static int core_scsi3_lunacl_depend_item(struct se_dev_entry *);
685	static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *);
686
687	/*
688	* Function used for handling PR registrations for ALL_TG_PT=1 and ALL_TG_PT=0
689	* modes.
690	*/
691	static struct t10_pr_registration *__core_scsi3_alloc_registration(
692	struct se_device *dev,
693	struct se_node_acl *nacl,
694	struct se_lun *lun,
695	struct se_dev_entry *deve,
696	u64 mapped_lun,
697	unsigned char *isid,
698	u64 sa_res_key,
699	int all_tg_pt,
700	int aptpl)
701	{
702	struct se_dev_entry *deve_tmp;
703	struct se_node_acl *nacl_tmp;
704	struct se_lun_acl *lacl_tmp;
705	struct se_lun *lun_tmp, *next, *dest_lun;
706	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
707	struct t10_pr_registration *pr_reg, *pr_reg_atp, *pr_reg_tmp, *pr_reg_tmp_safe;
708	int ret;
709	/*
710	* Create a registration for the I_T Nexus upon which the
711	* PROUT REGISTER was received.
712	*/
713	pr_reg = __core_scsi3_do_alloc_registration(dev, nacl, lun, dest_deve: deve, mapped_lun,
714	isid, sa_res_key, all_tg_pt,
715	aptpl);
716	if (!pr_reg)
717	return NULL;
718	/*
719	* Return pointer to pr_reg for ALL_TG_PT=0
720	*/
721	if (!all_tg_pt)
722	return pr_reg;
723	/*
724	* Create list of matching SCSI Initiator Port registrations
725	* for ALL_TG_PT=1
726	*/
727	spin_lock(lock: &dev->se_port_lock);
728	list_for_each_entry_safe(lun_tmp, next, &dev->dev_sep_list, lun_dev_link) {
729	if (!percpu_ref_tryget_live(ref: &lun_tmp->lun_ref))
730	continue;
731	spin_unlock(lock: &dev->se_port_lock);
732
733	spin_lock(lock: &lun_tmp->lun_deve_lock);
734	list_for_each_entry(deve_tmp, &lun_tmp->lun_deve_list, lun_link) {
735	/*
736	* This pointer will be NULL for demo mode MappedLUNs
737	* that have not been make explicit via a ConfigFS
738	* MappedLUN group for the SCSI Initiator Node ACL.
739	*/
740	if (!deve_tmp->se_lun_acl)
741	continue;
742
743	lacl_tmp = deve_tmp->se_lun_acl;
744	nacl_tmp = lacl_tmp->se_lun_nacl;
745	/*
746	* Skip the matching struct se_node_acl that is allocated
747	* above..
748	*/
749	if (nacl == nacl_tmp)
750	continue;
751	/*
752	* Only perform PR registrations for target ports on
753	* the same fabric module as the REGISTER w/ ALL_TG_PT=1
754	* arrived.
755	*/
756	if (tfo != nacl_tmp->se_tpg->se_tpg_tfo)
757	continue;
758	/*
759	* Look for a matching Initiator Node ACL in ASCII format
760	*/
761	if (strcmp(nacl->initiatorname, nacl_tmp->initiatorname))
762	continue;
763
764	kref_get(kref: &deve_tmp->pr_kref);
765	spin_unlock(lock: &lun_tmp->lun_deve_lock);
766	/*
767	* Grab a configfs group dependency that is released
768	* for the exception path at label out: below, or upon
769	* completion of adding ALL_TG_PT=1 registrations in
770	* __core_scsi3_add_registration()
771	*/
772	ret = core_scsi3_lunacl_depend_item(deve_tmp);
773	if (ret < 0) {
774	pr_err("core_scsi3_lunacl_depend"
775	"_item() failed\n");
776	percpu_ref_put(ref: &lun_tmp->lun_ref);
777	kref_put(kref: &deve_tmp->pr_kref, release: target_pr_kref_release);
778	goto out;
779	}
780	/*
781	* Located a matching SCSI Initiator Port on a different
782	* port, allocate the pr_reg_atp and attach it to the
783	* pr_reg->pr_reg_atp_list that will be processed once
784	* the original *pr_reg is processed in
785	* __core_scsi3_add_registration()
786	*/
787	dest_lun = deve_tmp->se_lun;
788
789	pr_reg_atp = __core_scsi3_do_alloc_registration(dev,
790	nacl: nacl_tmp, lun: dest_lun, dest_deve: deve_tmp,
791	mapped_lun: deve_tmp->mapped_lun, NULL,
792	sa_res_key, all_tg_pt, aptpl);
793	if (!pr_reg_atp) {
794	percpu_ref_put(ref: &lun_tmp->lun_ref);
795	core_scsi3_lunacl_undepend_item(deve_tmp);
796	goto out;
797	}
798
799	list_add_tail(new: &pr_reg_atp->pr_reg_atp_mem_list,
800	head: &pr_reg->pr_reg_atp_list);
801	spin_lock(lock: &lun_tmp->lun_deve_lock);
802	}
803	spin_unlock(lock: &lun_tmp->lun_deve_lock);
804
805	spin_lock(lock: &dev->se_port_lock);
806	percpu_ref_put(ref: &lun_tmp->lun_ref);
807	}
808	spin_unlock(lock: &dev->se_port_lock);
809
810	return pr_reg;
811	out:
812	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
813	&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
814	list_del(entry: &pr_reg_tmp->pr_reg_atp_mem_list);
815	core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
816	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg_tmp);
817	}
818	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg);
819	return NULL;
820	}
821
822	int core_scsi3_alloc_aptpl_registration(
823	struct t10_reservation *pr_tmpl,
824	u64 sa_res_key,
825	unsigned char *i_port,
826	unsigned char *isid,
827	u64 mapped_lun,
828	unsigned char *t_port,
829	u16 tpgt,
830	u64 target_lun,
831	int res_holder,
832	int all_tg_pt,
833	u8 type)
834	{
835	struct t10_pr_registration *pr_reg;
836
837	if (!i_port || !t_port || !sa_res_key) {
838	pr_err("Illegal parameters for APTPL registration\n");
839	return -EINVAL;
840	}
841
842	pr_reg = kmem_cache_zalloc(k: t10_pr_reg_cache, GFP_KERNEL);
843	if (!pr_reg) {
844	pr_err("Unable to allocate struct t10_pr_registration\n");
845	return -ENOMEM;
846	}
847
848	INIT_LIST_HEAD(list: &pr_reg->pr_reg_list);
849	INIT_LIST_HEAD(list: &pr_reg->pr_reg_abort_list);
850	INIT_LIST_HEAD(list: &pr_reg->pr_reg_aptpl_list);
851	INIT_LIST_HEAD(list: &pr_reg->pr_reg_atp_list);
852	INIT_LIST_HEAD(list: &pr_reg->pr_reg_atp_mem_list);
853	atomic_set(v: &pr_reg->pr_res_holders, i: 0);
854	pr_reg->pr_reg_nacl = NULL;
855	pr_reg->pr_reg_deve = NULL;
856	pr_reg->pr_res_mapped_lun = mapped_lun;
857	pr_reg->pr_aptpl_target_lun = target_lun;
858	pr_reg->pr_res_key = sa_res_key;
859	pr_reg->pr_reg_all_tg_pt = all_tg_pt;
860	pr_reg->pr_reg_aptpl = 1;
861	pr_reg->pr_res_scope = 0; /* Always LUN_SCOPE */
862	pr_reg->pr_res_type = type;
863	/*
864	* If an ISID value had been saved in APTPL metadata for this
865	* SCSI Initiator Port, restore it now.
866	*/
867	if (isid != NULL) {
868	pr_reg->pr_reg_bin_isid = get_unaligned_be64(p: isid);
869	snprintf(buf: pr_reg->pr_reg_isid, PR_REG_ISID_LEN, fmt: "%s", isid);
870	pr_reg->isid_present_at_reg = 1;
871	}
872	/*
873	* Copy the i_port and t_port information from caller.
874	*/
875	snprintf(buf: pr_reg->pr_iport, PR_APTPL_MAX_IPORT_LEN, fmt: "%s", i_port);
876	snprintf(buf: pr_reg->pr_tport, PR_APTPL_MAX_TPORT_LEN, fmt: "%s", t_port);
877	pr_reg->pr_reg_tpgt = tpgt;
878	/*
879	* Set pr_res_holder from caller, the pr_reg who is the reservation
880	* holder will get it's pointer set in core_scsi3_aptpl_reserve() once
881	* the Initiator Node LUN ACL from the fabric module is created for
882	* this registration.
883	*/
884	pr_reg->pr_res_holder = res_holder;
885
886	list_add_tail(new: &pr_reg->pr_reg_aptpl_list, head: &pr_tmpl->aptpl_reg_list);
887	pr_debug("SPC-3 PR APTPL Successfully added registration%s from"
888	" metadata\n", (res_holder) ? "+reservation" : "");
889	return 0;
890	}
891
892	static void core_scsi3_aptpl_reserve(
893	struct se_device *dev,
894	struct se_portal_group *tpg,
895	struct se_node_acl *node_acl,
896	struct t10_pr_registration *pr_reg)
897	{
898	char i_buf[PR_REG_ISID_ID_LEN] = { };
899
900	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
901
902	spin_lock(lock: &dev->dev_reservation_lock);
903	dev->dev_pr_res_holder = pr_reg;
904	spin_unlock(lock: &dev->dev_reservation_lock);
905
906	pr_debug("SPC-3 PR [%s] Service Action: APTPL RESERVE created"
907	" new reservation holder TYPE: %s ALL_TG_PT: %d\n",
908	tpg->se_tpg_tfo->fabric_name,
909	core_scsi3_pr_dump_type(pr_reg->pr_res_type),
910	(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
911	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
912	tpg->se_tpg_tfo->fabric_name, node_acl->initiatorname,
913	i_buf);
914	}
915
916	static void __core_scsi3_add_registration(struct se_device *, struct se_node_acl *,
917	struct t10_pr_registration *, enum register_type, int);
918
919	static int __core_scsi3_check_aptpl_registration(
920	struct se_device *dev,
921	struct se_portal_group *tpg,
922	struct se_lun *lun,
923	u64 target_lun,
924	struct se_node_acl *nacl,
925	u64 mapped_lun)
926	{
927	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
928	struct t10_reservation *pr_tmpl = &dev->t10_pr;
929	unsigned char i_port[PR_APTPL_MAX_IPORT_LEN] = { };
930	unsigned char t_port[PR_APTPL_MAX_TPORT_LEN] = { };
931	u16 tpgt;
932
933	/*
934	* Copy Initiator Port information from struct se_node_acl
935	*/
936	snprintf(buf: i_port, PR_APTPL_MAX_IPORT_LEN, fmt: "%s", nacl->initiatorname);
937	snprintf(buf: t_port, PR_APTPL_MAX_TPORT_LEN, fmt: "%s",
938	tpg->se_tpg_tfo->tpg_get_wwn(tpg));
939	tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
940	/*
941	* Look for the matching registrations+reservation from those
942	* created from APTPL metadata. Note that multiple registrations
943	* may exist for fabrics that use ISIDs in their SCSI Initiator Port
944	* TransportIDs.
945	*/
946	spin_lock(lock: &pr_tmpl->aptpl_reg_lock);
947	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
948	pr_reg_aptpl_list) {
949
950	if (!strcmp(pr_reg->pr_iport, i_port) &&
951	(pr_reg->pr_res_mapped_lun == mapped_lun) &&
952	!(strcmp(pr_reg->pr_tport, t_port)) &&
953	(pr_reg->pr_reg_tpgt == tpgt) &&
954	(pr_reg->pr_aptpl_target_lun == target_lun)) {
955	/*
956	* Obtain the ->pr_reg_deve pointer + reference, that
957	* is released by __core_scsi3_add_registration() below.
958	*/
959	rcu_read_lock();
960	pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
961	if (!pr_reg->pr_reg_deve) {
962	pr_err("Unable to locate PR APTPL %s mapped_lun:"
963	" %llu\n", nacl->initiatorname, mapped_lun);
964	rcu_read_unlock();
965	continue;
966	}
967	kref_get(kref: &pr_reg->pr_reg_deve->pr_kref);
968	rcu_read_unlock();
969
970	pr_reg->pr_reg_nacl = nacl;
971	pr_reg->tg_pt_sep_rtpi = lun->lun_tpg->tpg_rtpi;
972	list_del(entry: &pr_reg->pr_reg_aptpl_list);
973	spin_unlock(lock: &pr_tmpl->aptpl_reg_lock);
974	/*
975	* At this point all of the pointers in *pr_reg will
976	* be setup, so go ahead and add the registration.
977	*/
978	__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
979	/*
980	* If this registration is the reservation holder,
981	* make that happen now..
982	*/
983	if (pr_reg->pr_res_holder)
984	core_scsi3_aptpl_reserve(dev, tpg,
985	node_acl: nacl, pr_reg);
986	/*
987	* Reenable pr_aptpl_active to accept new metadata
988	* updates once the SCSI device is active again..
989	*/
990	spin_lock(lock: &pr_tmpl->aptpl_reg_lock);
991	pr_tmpl->pr_aptpl_active = 1;
992	}
993	}
994	spin_unlock(lock: &pr_tmpl->aptpl_reg_lock);
995
996	return 0;
997	}
998
999	int core_scsi3_check_aptpl_registration(
1000	struct se_device *dev,
1001	struct se_portal_group *tpg,
1002	struct se_lun *lun,
1003	struct se_node_acl *nacl,
1004	u64 mapped_lun)
1005	{
1006	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
1007	return 0;
1008
1009	return __core_scsi3_check_aptpl_registration(dev, tpg, lun,
1010	target_lun: lun->unpacked_lun, nacl,
1011	mapped_lun);
1012	}
1013
1014	static void __core_scsi3_dump_registration(
1015	const struct target_core_fabric_ops *tfo,
1016	struct se_device *dev,
1017	struct se_node_acl *nacl,
1018	struct t10_pr_registration *pr_reg,
1019	enum register_type register_type)
1020	{
1021	struct se_portal_group *se_tpg = nacl->se_tpg;
1022	char i_buf[PR_REG_ISID_ID_LEN] = { };
1023
1024	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
1025
1026	pr_debug("SPC-3 PR [%s] Service Action: REGISTER%s Initiator"
1027	" Node: %s%s\n", tfo->fabric_name, (register_type == REGISTER_AND_MOVE) ?
1028	"_AND_MOVE" : (register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ?
1029	"_AND_IGNORE_EXISTING_KEY" : "", nacl->initiatorname,
1030	i_buf);
1031	pr_debug("SPC-3 PR [%s] registration on Target Port: %s,0x%04x\n",
1032	tfo->fabric_name, tfo->tpg_get_wwn(se_tpg),
1033	tfo->tpg_get_tag(se_tpg));
1034	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1035	" Port(s)\n", tfo->fabric_name,
1036	(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1037	dev->transport->name);
1038	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1039	" 0x%08x APTPL: %d\n", tfo->fabric_name,
1040	pr_reg->pr_res_key, pr_reg->pr_res_generation,
1041	pr_reg->pr_reg_aptpl);
1042	}
1043
1044	static void __core_scsi3_add_registration(
1045	struct se_device *dev,
1046	struct se_node_acl *nacl,
1047	struct t10_pr_registration *pr_reg,
1048	enum register_type register_type,
1049	int register_move)
1050	{
1051	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
1052	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1053	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1054	struct se_dev_entry *deve;
1055
1056	/*
1057	* Increment PRgeneration counter for struct se_device upon a successful
1058	* REGISTER, see spc4r17 section 6.3.2 READ_KEYS service action
1059	*
1060	* Also, when register_move = 1 for PROUT REGISTER_AND_MOVE service
1061	* action, the struct se_device->dev_reservation_lock will already be held,
1062	* so we do not call core_scsi3_pr_generation() which grabs the lock
1063	* for the REGISTER.
1064	*/
1065	pr_reg->pr_res_generation = (register_move) ?
1066	dev->t10_pr.pr_generation++ :
1067	core_scsi3_pr_generation(dev);
1068
1069	spin_lock(lock: &pr_tmpl->registration_lock);
1070	list_add_tail(new: &pr_reg->pr_reg_list, head: &pr_tmpl->registration_list);
1071
1072	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
1073	spin_unlock(lock: &pr_tmpl->registration_lock);
1074	/*
1075	* Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
1076	*/
1077	if (!pr_reg->pr_reg_all_tg_pt || register_move)
1078	goto out;
1079	/*
1080	* Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
1081	* allocated in __core_scsi3_alloc_registration()
1082	*/
1083	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1084	&pr_reg->pr_reg_atp_list, pr_reg_atp_mem_list) {
1085	struct se_node_acl *nacl_tmp = pr_reg_tmp->pr_reg_nacl;
1086
1087	list_del(entry: &pr_reg_tmp->pr_reg_atp_mem_list);
1088
1089	pr_reg_tmp->pr_res_generation = core_scsi3_pr_generation(dev);
1090
1091	spin_lock(lock: &pr_tmpl->registration_lock);
1092	list_add_tail(new: &pr_reg_tmp->pr_reg_list,
1093	head: &pr_tmpl->registration_list);
1094
1095	__core_scsi3_dump_registration(tfo, dev, nacl: nacl_tmp, pr_reg: pr_reg_tmp,
1096	register_type);
1097	spin_unlock(lock: &pr_tmpl->registration_lock);
1098	/*
1099	* Drop configfs group dependency reference and deve->pr_kref
1100	* obtained from __core_scsi3_alloc_registration() code.
1101	*/
1102	rcu_read_lock();
1103	deve = pr_reg_tmp->pr_reg_deve;
1104	if (deve) {
1105	set_bit(DEF_PR_REG_ACTIVE, addr: &deve->deve_flags);
1106	core_scsi3_lunacl_undepend_item(deve);
1107	pr_reg_tmp->pr_reg_deve = NULL;
1108	}
1109	rcu_read_unlock();
1110	}
1111	out:
1112	/*
1113	* Drop deve->pr_kref obtained in __core_scsi3_do_alloc_registration()
1114	*/
1115	rcu_read_lock();
1116	deve = pr_reg->pr_reg_deve;
1117	if (deve) {
1118	set_bit(DEF_PR_REG_ACTIVE, addr: &deve->deve_flags);
1119	kref_put(kref: &deve->pr_kref, release: target_pr_kref_release);
1120	pr_reg->pr_reg_deve = NULL;
1121	}
1122	rcu_read_unlock();
1123	}
1124
1125	static int core_scsi3_alloc_registration(
1126	struct se_device *dev,
1127	struct se_node_acl *nacl,
1128	struct se_lun *lun,
1129	struct se_dev_entry *deve,
1130	u64 mapped_lun,
1131	unsigned char *isid,
1132	u64 sa_res_key,
1133	int all_tg_pt,
1134	int aptpl,
1135	enum register_type register_type,
1136	int register_move)
1137	{
1138	struct t10_pr_registration *pr_reg;
1139
1140	pr_reg = __core_scsi3_alloc_registration(dev, nacl, lun, deve, mapped_lun,
1141	isid, sa_res_key, all_tg_pt,
1142	aptpl);
1143	if (!pr_reg)
1144	return -EPERM;
1145
1146	__core_scsi3_add_registration(dev, nacl, pr_reg,
1147	register_type, register_move);
1148	return 0;
1149	}
1150
1151	static struct t10_pr_registration *__core_scsi3_locate_pr_reg(
1152	struct se_device *dev,
1153	struct se_node_acl *nacl,
1154	unsigned char *isid)
1155	{
1156	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1157	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
1158
1159	spin_lock(lock: &pr_tmpl->registration_lock);
1160	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1161	&pr_tmpl->registration_list, pr_reg_list) {
1162	/*
1163	* First look for a matching struct se_node_acl
1164	*/
1165	if (pr_reg->pr_reg_nacl != nacl)
1166	continue;
1167
1168	/*
1169	* If this registration does NOT contain a fabric provided
1170	* ISID, then we have found a match.
1171	*/
1172	if (!pr_reg->isid_present_at_reg) {
1173	atomic_inc_mb(v: &pr_reg->pr_res_holders);
1174	spin_unlock(lock: &pr_tmpl->registration_lock);
1175	return pr_reg;
1176	}
1177	/*
1178	* If the *pr_reg contains a fabric defined ISID for multi-value
1179	* SCSI Initiator Port TransportIDs, then we expect a valid
1180	* matching ISID to be provided by the local SCSI Initiator Port.
1181	*/
1182	if (!isid)
1183	continue;
1184	if (strcmp(isid, pr_reg->pr_reg_isid))
1185	continue;
1186
1187	atomic_inc_mb(v: &pr_reg->pr_res_holders);
1188	spin_unlock(lock: &pr_tmpl->registration_lock);
1189	return pr_reg;
1190	}
1191	spin_unlock(lock: &pr_tmpl->registration_lock);
1192
1193	return NULL;
1194	}
1195
1196	static struct t10_pr_registration *core_scsi3_locate_pr_reg(
1197	struct se_device *dev,
1198	struct se_node_acl *nacl,
1199	struct se_session *sess)
1200	{
1201	struct se_portal_group *tpg = nacl->se_tpg;
1202	unsigned char buf[PR_REG_ISID_LEN] = { };
1203	unsigned char *isid_ptr = NULL;
1204
1205	if (tpg->se_tpg_tfo->sess_get_initiator_sid != NULL) {
1206	tpg->se_tpg_tfo->sess_get_initiator_sid(sess, &buf[0],
1207	PR_REG_ISID_LEN);
1208	isid_ptr = &buf[0];
1209	}
1210
1211	return __core_scsi3_locate_pr_reg(dev, nacl, isid: isid_ptr);
1212	}
1213
1214	static void core_scsi3_put_pr_reg(struct t10_pr_registration *pr_reg)
1215	{
1216	atomic_dec_mb(v: &pr_reg->pr_res_holders);
1217	}
1218
1219	static int core_scsi3_check_implicit_release(
1220	struct se_device *dev,
1221	struct t10_pr_registration *pr_reg)
1222	{
1223	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1224	struct t10_pr_registration *pr_res_holder;
1225	int ret = 0;
1226
1227	spin_lock(lock: &dev->dev_reservation_lock);
1228	pr_res_holder = dev->dev_pr_res_holder;
1229	if (!pr_res_holder) {
1230	spin_unlock(lock: &dev->dev_reservation_lock);
1231	return ret;
1232	}
1233	if (pr_res_holder == pr_reg) {
1234	/*
1235	* Perform an implicit RELEASE if the registration that
1236	* is being released is holding the reservation.
1237	*
1238	* From spc4r17, section 5.7.11.1:
1239	*
1240	* e) If the I_T nexus is the persistent reservation holder
1241	* and the persistent reservation is not an all registrants
1242	* type, then a PERSISTENT RESERVE OUT command with REGISTER
1243	* service action or REGISTER AND IGNORE EXISTING KEY
1244	* service action with the SERVICE ACTION RESERVATION KEY
1245	* field set to zero (see 5.7.11.3).
1246	*/
1247	__core_scsi3_complete_pro_release(dev, nacl, pr_reg, 0, 1);
1248	ret = 1;
1249	/*
1250	* For 'All Registrants' reservation types, all existing
1251	* registrations are still processed as reservation holders
1252	* in core_scsi3_pr_seq_non_holder() after the initial
1253	* reservation holder is implicitly released here.
1254	*/
1255	} else if (pr_reg->pr_reg_all_tg_pt &&
1256	(!strcmp(pr_res_holder->pr_reg_nacl->initiatorname,
1257	pr_reg->pr_reg_nacl->initiatorname)) &&
1258	(pr_res_holder->pr_res_key == pr_reg->pr_res_key)) {
1259	pr_err("SPC-3 PR: Unable to perform ALL_TG_PT=1"
1260	" UNREGISTER while existing reservation with matching"
1261	" key 0x%016Lx is present from another SCSI Initiator"
1262	" Port\n", pr_reg->pr_res_key);
1263	ret = -EPERM;
1264	}
1265	spin_unlock(lock: &dev->dev_reservation_lock);
1266
1267	return ret;
1268	}
1269
1270	static void __core_scsi3_free_registration(
1271	struct se_device *dev,
1272	struct t10_pr_registration *pr_reg,
1273	struct list_head *preempt_and_abort_list,
1274	int dec_holders)
1275	__releases(&pr_tmpl->registration_lock)
1276	__acquires(&pr_tmpl->registration_lock)
1277	{
1278	const struct target_core_fabric_ops *tfo =
1279	pr_reg->pr_reg_nacl->se_tpg->se_tpg_tfo;
1280	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1281	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
1282	struct se_dev_entry *deve;
1283	char i_buf[PR_REG_ISID_ID_LEN] = { };
1284
1285	lockdep_assert_held(&pr_tmpl->registration_lock);
1286
1287	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
1288
1289	if (!list_empty(head: &pr_reg->pr_reg_list))
1290	list_del(entry: &pr_reg->pr_reg_list);
1291	/*
1292	* Caller accessing *pr_reg using core_scsi3_locate_pr_reg(),
1293	* so call core_scsi3_put_pr_reg() to decrement our reference.
1294	*/
1295	if (dec_holders)
1296	core_scsi3_put_pr_reg(pr_reg);
1297
1298	spin_unlock(lock: &pr_tmpl->registration_lock);
1299	/*
1300	* Wait until all reference from any other I_T nexuses for this
1301	* *pr_reg have been released. Because list_del() is called above,
1302	* the last core_scsi3_put_pr_reg(pr_reg) will release this reference
1303	* count back to zero, and we release *pr_reg.
1304	*/
1305	while (atomic_read(v: &pr_reg->pr_res_holders) != 0) {
1306	pr_debug("SPC-3 PR [%s] waiting for pr_res_holders\n",
1307	tfo->fabric_name);
1308	cpu_relax();
1309	}
1310
1311	rcu_read_lock();
1312	deve = target_nacl_find_deve(nacl, pr_reg->pr_res_mapped_lun);
1313	if (deve)
1314	clear_bit(DEF_PR_REG_ACTIVE, addr: &deve->deve_flags);
1315	rcu_read_unlock();
1316
1317	spin_lock(lock: &pr_tmpl->registration_lock);
1318	pr_debug("SPC-3 PR [%s] Service Action: UNREGISTER Initiator"
1319	" Node: %s%s\n", tfo->fabric_name,
1320	pr_reg->pr_reg_nacl->initiatorname,
1321	i_buf);
1322	pr_debug("SPC-3 PR [%s] for %s TCM Subsystem %s Object Target"
1323	" Port(s)\n", tfo->fabric_name,
1324	(pr_reg->pr_reg_all_tg_pt) ? "ALL" : "SINGLE",
1325	dev->transport->name);
1326	pr_debug("SPC-3 PR [%s] SA Res Key: 0x%016Lx PRgeneration:"
1327	" 0x%08x\n", tfo->fabric_name, pr_reg->pr_res_key,
1328	pr_reg->pr_res_generation);
1329
1330	if (!preempt_and_abort_list) {
1331	pr_reg->pr_reg_deve = NULL;
1332	pr_reg->pr_reg_nacl = NULL;
1333	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg);
1334	return;
1335	}
1336	/*
1337	* For PREEMPT_AND_ABORT, the list of *pr_reg in preempt_and_abort_list
1338	* are released once the ABORT_TASK_SET has completed..
1339	*/
1340	list_add_tail(new: &pr_reg->pr_reg_abort_list, head: preempt_and_abort_list);
1341	}
1342
1343	void core_scsi3_free_pr_reg_from_nacl(
1344	struct se_device *dev,
1345	struct se_node_acl *nacl)
1346	{
1347	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1348	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1349	bool free_reg = false;
1350	/*
1351	* If the passed se_node_acl matches the reservation holder,
1352	* release the reservation.
1353	*/
1354	spin_lock(lock: &dev->dev_reservation_lock);
1355	pr_res_holder = dev->dev_pr_res_holder;
1356	if ((pr_res_holder != NULL) &&
1357	(pr_res_holder->pr_reg_nacl == nacl)) {
1358	__core_scsi3_complete_pro_release(dev, nacl, pr_res_holder, 0, 1);
1359	free_reg = true;
1360	}
1361	spin_unlock(lock: &dev->dev_reservation_lock);
1362	/*
1363	* Release any registration associated with the struct se_node_acl.
1364	*/
1365	spin_lock(lock: &pr_tmpl->registration_lock);
1366	if (pr_res_holder && free_reg)
1367	__core_scsi3_free_registration(dev, pr_reg: pr_res_holder, NULL, dec_holders: 0);
1368
1369	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1370	&pr_tmpl->registration_list, pr_reg_list) {
1371
1372	if (pr_reg->pr_reg_nacl != nacl)
1373	continue;
1374
1375	__core_scsi3_free_registration(dev, pr_reg, NULL, dec_holders: 0);
1376	}
1377	spin_unlock(lock: &pr_tmpl->registration_lock);
1378	}
1379
1380	void core_scsi3_free_all_registrations(
1381	struct se_device *dev)
1382	{
1383	struct t10_reservation *pr_tmpl = &dev->t10_pr;
1384	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_res_holder;
1385
1386	spin_lock(lock: &dev->dev_reservation_lock);
1387	pr_res_holder = dev->dev_pr_res_holder;
1388	if (pr_res_holder != NULL) {
1389	struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
1390	__core_scsi3_complete_pro_release(dev, pr_res_nacl,
1391	pr_res_holder, 0, 0);
1392	}
1393	spin_unlock(lock: &dev->dev_reservation_lock);
1394
1395	spin_lock(lock: &pr_tmpl->registration_lock);
1396	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
1397	&pr_tmpl->registration_list, pr_reg_list) {
1398
1399	__core_scsi3_free_registration(dev, pr_reg, NULL, dec_holders: 0);
1400	}
1401	spin_unlock(lock: &pr_tmpl->registration_lock);
1402
1403	spin_lock(lock: &pr_tmpl->aptpl_reg_lock);
1404	list_for_each_entry_safe(pr_reg, pr_reg_tmp, &pr_tmpl->aptpl_reg_list,
1405	pr_reg_aptpl_list) {
1406	list_del(entry: &pr_reg->pr_reg_aptpl_list);
1407	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg);
1408	}
1409	spin_unlock(lock: &pr_tmpl->aptpl_reg_lock);
1410	}
1411
1412	static int core_scsi3_tpg_depend_item(struct se_portal_group *tpg)
1413	{
1414	return target_depend_item(item: &tpg->tpg_group.cg_item);
1415	}
1416
1417	static void core_scsi3_tpg_undepend_item(struct se_portal_group *tpg)
1418	{
1419	target_undepend_item(item: &tpg->tpg_group.cg_item);
1420	atomic_dec_mb(v: &tpg->tpg_pr_ref_count);
1421	}
1422
1423	static int core_scsi3_nodeacl_depend_item(struct se_node_acl *nacl)
1424	{
1425	if (nacl->dynamic_node_acl)
1426	return 0;
1427	return target_depend_item(item: &nacl->acl_group.cg_item);
1428	}
1429
1430	static void core_scsi3_nodeacl_undepend_item(struct se_node_acl *nacl)
1431	{
1432	if (!nacl->dynamic_node_acl)
1433	target_undepend_item(item: &nacl->acl_group.cg_item);
1434	atomic_dec_mb(v: &nacl->acl_pr_ref_count);
1435	}
1436
1437	static int core_scsi3_lunacl_depend_item(struct se_dev_entry *se_deve)
1438	{
1439	/*
1440	* For nacl->dynamic_node_acl=1
1441	*/
1442	if (!se_deve->se_lun_acl)
1443	return 0;
1444
1445	return target_depend_item(item: &se_deve->se_lun_acl->se_lun_group.cg_item);
1446	}
1447
1448	static void core_scsi3_lunacl_undepend_item(struct se_dev_entry *se_deve)
1449	{
1450	/*
1451	* For nacl->dynamic_node_acl=1
1452	*/
1453	if (!se_deve->se_lun_acl) {
1454	kref_put(kref: &se_deve->pr_kref, release: target_pr_kref_release);
1455	return;
1456	}
1457
1458	target_undepend_item(item: &se_deve->se_lun_acl->se_lun_group.cg_item);
1459	kref_put(kref: &se_deve->pr_kref, release: target_pr_kref_release);
1460	}
1461
1462	static sense_reason_t
1463	core_scsi3_decode_spec_i_port(
1464	struct se_cmd *cmd,
1465	struct se_portal_group *tpg,
1466	unsigned char *l_isid,
1467	u64 sa_res_key,
1468	int all_tg_pt,
1469	int aptpl)
1470	{
1471	struct se_device *dev = cmd->se_dev;
1472	struct se_portal_group *dest_tpg = NULL, *tmp_tpg;
1473	struct se_session *se_sess = cmd->se_sess;
1474	struct se_node_acl *dest_node_acl = NULL;
1475	struct se_dev_entry *dest_se_deve = NULL;
1476	struct t10_pr_registration *dest_pr_reg, *local_pr_reg, *pr_reg_e;
1477	struct t10_pr_registration *pr_reg_tmp, *pr_reg_tmp_safe;
1478	LIST_HEAD(tid_dest_list);
1479	struct pr_transport_id_holder *tidh_new, *tidh, *tidh_tmp;
1480	unsigned char *buf, *ptr, proto_ident;
1481	const unsigned char *i_str = NULL;
1482	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN];
1483	sense_reason_t ret;
1484	u32 tpdl, tid_len = 0;
1485	u32 dest_rtpi = 0;
1486
1487	/*
1488	* Allocate a struct pr_transport_id_holder and setup the
1489	* local_node_acl pointer and add to struct list_head tid_dest_list
1490	* for add registration processing in the loop of tid_dest_list below.
1491	*/
1492	tidh_new = kzalloc(size: sizeof(struct pr_transport_id_holder), GFP_KERNEL);
1493	if (!tidh_new) {
1494	pr_err("Unable to allocate tidh_new\n");
1495	return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1496	}
1497	INIT_LIST_HEAD(list: &tidh_new->dest_list);
1498	tidh_new->dest_tpg = tpg;
1499	tidh_new->dest_node_acl = se_sess->se_node_acl;
1500
1501	local_pr_reg = __core_scsi3_alloc_registration(dev: cmd->se_dev,
1502	nacl: se_sess->se_node_acl, lun: cmd->se_lun,
1503	NULL, mapped_lun: cmd->orig_fe_lun, isid: l_isid,
1504	sa_res_key, all_tg_pt, aptpl);
1505	if (!local_pr_reg) {
1506	kfree(objp: tidh_new);
1507	return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1508	}
1509
1510	if (core_scsi3_lunacl_depend_item(se_deve: local_pr_reg->pr_reg_deve)) {
1511	kfree(objp: tidh_new);
1512	kref_put(kref: &local_pr_reg->pr_reg_deve->pr_kref,
1513	release: target_pr_kref_release);
1514	kmem_cache_free(s: t10_pr_reg_cache, objp: local_pr_reg);
1515	return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1516	}
1517
1518	tidh_new->dest_pr_reg = local_pr_reg;
1519	list_add_tail(new: &tidh_new->dest_list, head: &tid_dest_list);
1520
1521	if (cmd->data_length < 28) {
1522	pr_warn("SPC-PR: Received PR OUT parameter list"
1523	" length too small: %u\n", cmd->data_length);
1524	ret = TCM_INVALID_PARAMETER_LIST;
1525	goto out;
1526	}
1527
1528	buf = transport_kmap_data_sg(cmd);
1529	if (!buf) {
1530	ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1531	goto out;
1532	}
1533
1534	/*
1535	* For a PERSISTENT RESERVE OUT specify initiator ports payload,
1536	* first extract TransportID Parameter Data Length, and make sure
1537	* the value matches up to the SCSI expected data transfer length.
1538	*/
1539	tpdl = get_unaligned_be32(p: &buf[24]);
1540
1541	if ((tpdl + 28) != cmd->data_length) {
1542	pr_err("SPC-3 PR: Illegal tpdl: %u + 28 byte header"
1543	" does not equal CDB data_length: %u\n", tpdl,
1544	cmd->data_length);
1545	ret = TCM_INVALID_PARAMETER_LIST;
1546	goto out_unmap;
1547	}
1548	/*
1549	* Start processing the received transport IDs using the
1550	* receiving I_T Nexus portal's fabric dependent methods to
1551	* obtain the SCSI Initiator Port/Device Identifiers.
1552	*/
1553	ptr = &buf[28];
1554
1555	while (tpdl > 0) {
1556	struct se_lun *dest_lun, *tmp_lun;
1557
1558	proto_ident = (ptr[0] & 0x0f);
1559	dest_tpg = NULL;
1560
1561	spin_lock(lock: &dev->se_port_lock);
1562	list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
1563	tmp_tpg = tmp_lun->lun_tpg;
1564
1565	/*
1566	* Look for the matching proto_ident provided by
1567	* the received TransportID
1568	*/
1569	if (tmp_tpg->proto_id != proto_ident)
1570	continue;
1571	dest_rtpi = tmp_lun->lun_tpg->tpg_rtpi;
1572
1573	iport_ptr = NULL;
1574	i_str = target_parse_pr_out_transport_id(tpg: tmp_tpg,
1575	buf: ptr, out_tid_len: &tid_len, port_nexus_ptr: &iport_ptr);
1576	if (!i_str)
1577	continue;
1578	/*
1579	* Determine if this SCSI device server requires that
1580	* SCSI Intiatior TransportID w/ ISIDs is enforced
1581	* for fabric modules (iSCSI) requiring them.
1582	*/
1583	if (tpg->se_tpg_tfo->sess_get_initiator_sid &&
1584	dev->dev_attrib.enforce_pr_isids &&
1585	!iport_ptr) {
1586	pr_warn("SPC-PR: enforce_pr_isids is set but a isid has not been sent in the SPEC_I_PT data for %s.",
1587	i_str);
1588	ret = TCM_INVALID_PARAMETER_LIST;
1589	spin_unlock(lock: &dev->se_port_lock);
1590	goto out_unmap;
1591	}
1592
1593	atomic_inc_mb(v: &tmp_tpg->tpg_pr_ref_count);
1594	spin_unlock(lock: &dev->se_port_lock);
1595
1596	if (core_scsi3_tpg_depend_item(tpg: tmp_tpg)) {
1597	pr_err(" core_scsi3_tpg_depend_item()"
1598	" for tmp_tpg\n");
1599	atomic_dec_mb(v: &tmp_tpg->tpg_pr_ref_count);
1600	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1601	goto out_unmap;
1602	}
1603	/*
1604	* Locate the destination initiator ACL to be registered
1605	* from the decoded fabric module specific TransportID
1606	* at *i_str.
1607	*/
1608	mutex_lock(&tmp_tpg->acl_node_mutex);
1609	dest_node_acl = __core_tpg_get_initiator_node_acl(
1610	tpg: tmp_tpg, i_str);
1611	if (dest_node_acl)
1612	atomic_inc_mb(v: &dest_node_acl->acl_pr_ref_count);
1613	mutex_unlock(lock: &tmp_tpg->acl_node_mutex);
1614
1615	if (!dest_node_acl) {
1616	core_scsi3_tpg_undepend_item(tpg: tmp_tpg);
1617	spin_lock(lock: &dev->se_port_lock);
1618	continue;
1619	}
1620
1621	if (core_scsi3_nodeacl_depend_item(nacl: dest_node_acl)) {
1622	pr_err("configfs_depend_item() failed"
1623	" for dest_node_acl->acl_group\n");
1624	atomic_dec_mb(v: &dest_node_acl->acl_pr_ref_count);
1625	core_scsi3_tpg_undepend_item(tpg: tmp_tpg);
1626	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1627	goto out_unmap;
1628	}
1629
1630	dest_tpg = tmp_tpg;
1631	pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s Port RTPI: %u\n",
1632	dest_tpg->se_tpg_tfo->fabric_name,
1633	dest_node_acl->initiatorname, dest_rtpi);
1634
1635	spin_lock(lock: &dev->se_port_lock);
1636	break;
1637	}
1638	spin_unlock(lock: &dev->se_port_lock);
1639
1640	if (!dest_tpg) {
1641	pr_err("SPC-3 PR SPEC_I_PT: Unable to locate"
1642	" dest_tpg\n");
1643	ret = TCM_INVALID_PARAMETER_LIST;
1644	goto out_unmap;
1645	}
1646
1647	pr_debug("SPC-3 PR SPEC_I_PT: Got %s data_length: %u tpdl: %u"
1648	" tid_len: %d for %s + %s\n",
1649	dest_tpg->se_tpg_tfo->fabric_name, cmd->data_length,
1650	tpdl, tid_len, i_str, iport_ptr);
1651
1652	if (tid_len > tpdl) {
1653	pr_err("SPC-3 PR SPEC_I_PT: Illegal tid_len:"
1654	" %u for Transport ID: %s\n", tid_len, ptr);
1655	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1656	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1657	ret = TCM_INVALID_PARAMETER_LIST;
1658	goto out_unmap;
1659	}
1660	/*
1661	* Locate the desintation struct se_dev_entry pointer for matching
1662	* RELATIVE TARGET PORT IDENTIFIER on the receiving I_T Nexus
1663	* Target Port.
1664	*/
1665	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl,
1666	dest_rtpi);
1667	if (!dest_se_deve) {
1668	pr_err("Unable to locate %s dest_se_deve from destination RTPI: %u\n",
1669	dest_tpg->se_tpg_tfo->fabric_name,
1670	dest_rtpi);
1671
1672	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1673	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1674	ret = TCM_INVALID_PARAMETER_LIST;
1675	goto out_unmap;
1676	}
1677
1678	if (core_scsi3_lunacl_depend_item(se_deve: dest_se_deve)) {
1679	pr_err("core_scsi3_lunacl_depend_item()"
1680	" failed\n");
1681	kref_put(kref: &dest_se_deve->pr_kref, release: target_pr_kref_release);
1682	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1683	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1684	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1685	goto out_unmap;
1686	}
1687
1688	pr_debug("SPC-3 PR SPEC_I_PT: Located %s Node: %s"
1689	" dest_se_deve mapped_lun: %llu\n",
1690	dest_tpg->se_tpg_tfo->fabric_name,
1691	dest_node_acl->initiatorname, dest_se_deve->mapped_lun);
1692
1693	/*
1694	* Skip any TransportIDs that already have a registration for
1695	* this target port.
1696	*/
1697	pr_reg_e = __core_scsi3_locate_pr_reg(dev, nacl: dest_node_acl,
1698	isid: iport_ptr);
1699	if (pr_reg_e) {
1700	core_scsi3_put_pr_reg(pr_reg: pr_reg_e);
1701	core_scsi3_lunacl_undepend_item(se_deve: dest_se_deve);
1702	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1703	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1704	ptr += tid_len;
1705	tpdl -= tid_len;
1706	tid_len = 0;
1707	continue;
1708	}
1709	/*
1710	* Allocate a struct pr_transport_id_holder and setup
1711	* the dest_node_acl and dest_se_deve pointers for the
1712	* loop below.
1713	*/
1714	tidh_new = kzalloc(size: sizeof(struct pr_transport_id_holder),
1715	GFP_KERNEL);
1716	if (!tidh_new) {
1717	pr_err("Unable to allocate tidh_new\n");
1718	core_scsi3_lunacl_undepend_item(se_deve: dest_se_deve);
1719	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1720	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1721	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1722	goto out_unmap;
1723	}
1724	INIT_LIST_HEAD(list: &tidh_new->dest_list);
1725	tidh_new->dest_tpg = dest_tpg;
1726	tidh_new->dest_node_acl = dest_node_acl;
1727	tidh_new->dest_se_deve = dest_se_deve;
1728
1729	/*
1730	* Allocate, but do NOT add the registration for the
1731	* TransportID referenced SCSI Initiator port. This
1732	* done because of the following from spc4r17 in section
1733	* 6.14.3 wrt SPEC_I_PT:
1734	*
1735	* "If a registration fails for any initiator port (e.g., if th
1736	* logical unit does not have enough resources available to
1737	* hold the registration information), no registrations shall be
1738	* made, and the command shall be terminated with
1739	* CHECK CONDITION status."
1740	*
1741	* That means we call __core_scsi3_alloc_registration() here,
1742	* and then call __core_scsi3_add_registration() in the
1743	* 2nd loop which will never fail.
1744	*/
1745	dest_lun = dest_se_deve->se_lun;
1746
1747	dest_pr_reg = __core_scsi3_alloc_registration(dev: cmd->se_dev,
1748	nacl: dest_node_acl, lun: dest_lun, deve: dest_se_deve,
1749	mapped_lun: dest_se_deve->mapped_lun, isid: iport_ptr,
1750	sa_res_key, all_tg_pt, aptpl);
1751	if (!dest_pr_reg) {
1752	core_scsi3_lunacl_undepend_item(se_deve: dest_se_deve);
1753	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1754	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1755	kfree(objp: tidh_new);
1756	ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
1757	goto out_unmap;
1758	}
1759	tidh_new->dest_pr_reg = dest_pr_reg;
1760	list_add_tail(new: &tidh_new->dest_list, head: &tid_dest_list);
1761
1762	ptr += tid_len;
1763	tpdl -= tid_len;
1764	tid_len = 0;
1765
1766	}
1767
1768	transport_kunmap_data_sg(cmd);
1769
1770	/*
1771	* Go ahead and create a registrations from tid_dest_list for the
1772	* SPEC_I_PT provided TransportID for the *tidh referenced dest_node_acl
1773	* and dest_se_deve.
1774	*
1775	* The SA Reservation Key from the PROUT is set for the
1776	* registration, and ALL_TG_PT is also passed. ALL_TG_PT=1
1777	* means that the TransportID Initiator port will be
1778	* registered on all of the target ports in the SCSI target device
1779	* ALL_TG_PT=0 means the registration will only be for the
1780	* SCSI target port the PROUT REGISTER with SPEC_I_PT=1
1781	* was received.
1782	*/
1783	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1784	dest_tpg = tidh->dest_tpg;
1785	dest_node_acl = tidh->dest_node_acl;
1786	dest_se_deve = tidh->dest_se_deve;
1787	dest_pr_reg = tidh->dest_pr_reg;
1788
1789	list_del(entry: &tidh->dest_list);
1790	kfree(objp: tidh);
1791
1792	memset(i_buf, 0, PR_REG_ISID_ID_LEN);
1793	core_pr_dump_initiator_port(pr_reg: dest_pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
1794
1795	__core_scsi3_add_registration(dev: cmd->se_dev, nacl: dest_node_acl,
1796	pr_reg: dest_pr_reg, register_type: 0, register_move: 0);
1797
1798	pr_debug("SPC-3 PR [%s] SPEC_I_PT: Successfully"
1799	" registered Transport ID for Node: %s%s Mapped LUN:"
1800	" %llu\n", dest_tpg->se_tpg_tfo->fabric_name,
1801	dest_node_acl->initiatorname, i_buf, (dest_se_deve) ?
1802	dest_se_deve->mapped_lun : 0);
1803
1804	if (dest_pr_reg == local_pr_reg)
1805	continue;
1806
1807	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1808	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1809	}
1810
1811	return 0;
1812	out_unmap:
1813	transport_kunmap_data_sg(cmd);
1814	out:
1815	/*
1816	* For the failure case, release everything from tid_dest_list
1817	* including *dest_pr_reg and the configfs dependances..
1818	*/
1819	list_for_each_entry_safe(tidh, tidh_tmp, &tid_dest_list, dest_list) {
1820	bool is_local = false;
1821
1822	dest_tpg = tidh->dest_tpg;
1823	dest_node_acl = tidh->dest_node_acl;
1824	dest_se_deve = tidh->dest_se_deve;
1825	dest_pr_reg = tidh->dest_pr_reg;
1826
1827	if (dest_pr_reg == local_pr_reg)
1828	is_local = true;
1829
1830	list_del(entry: &tidh->dest_list);
1831	kfree(objp: tidh);
1832	/*
1833	* Release any extra ALL_TG_PT=1 registrations for
1834	* the SPEC_I_PT=1 case.
1835	*/
1836	list_for_each_entry_safe(pr_reg_tmp, pr_reg_tmp_safe,
1837	&dest_pr_reg->pr_reg_atp_list,
1838	pr_reg_atp_mem_list) {
1839	list_del(entry: &pr_reg_tmp->pr_reg_atp_mem_list);
1840	core_scsi3_lunacl_undepend_item(se_deve: pr_reg_tmp->pr_reg_deve);
1841	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg_tmp);
1842	}
1843
1844	kmem_cache_free(s: t10_pr_reg_cache, objp: dest_pr_reg);
1845	core_scsi3_lunacl_undepend_item(se_deve: dest_se_deve);
1846
1847	if (is_local)
1848	continue;
1849
1850	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
1851	core_scsi3_tpg_undepend_item(tpg: dest_tpg);
1852	}
1853	return ret;
1854	}
1855
1856	static int core_scsi3_update_aptpl_buf(
1857	struct se_device *dev,
1858	unsigned char *buf,
1859	u32 pr_aptpl_buf_len)
1860	{
1861	struct se_portal_group *tpg;
1862	struct t10_pr_registration *pr_reg;
1863	unsigned char tmp[512], isid_buf[32];
1864	ssize_t len = 0;
1865	int reg_count = 0;
1866	int ret = 0;
1867
1868	spin_lock(lock: &dev->dev_reservation_lock);
1869	spin_lock(lock: &dev->t10_pr.registration_lock);
1870	/*
1871	* Walk the registration list..
1872	*/
1873	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
1874	pr_reg_list) {
1875
1876	tmp[0] = '\0';
1877	isid_buf[0] = '\0';
1878	tpg = pr_reg->pr_reg_nacl->se_tpg;
1879	/*
1880	* Write out any ISID value to APTPL metadata that was included
1881	* in the original registration.
1882	*/
1883	if (pr_reg->isid_present_at_reg)
1884	snprintf(buf: isid_buf, size: 32, fmt: "initiator_sid=%s\n",
1885	pr_reg->pr_reg_isid);
1886	/*
1887	* Include special metadata if the pr_reg matches the
1888	* reservation holder.
1889	*/
1890	if (dev->dev_pr_res_holder == pr_reg) {
1891	snprintf(buf: tmp, size: 512, fmt: "PR_REG_START: %d"
1892	"\ninitiator_fabric=%s\n"
1893	"initiator_node=%s\n%s"
1894	"sa_res_key=%llu\n"
1895	"res_holder=1\nres_type=%02x\n"
1896	"res_scope=%02x\nres_all_tg_pt=%d\n"
1897	"mapped_lun=%llu\n", reg_count,
1898	tpg->se_tpg_tfo->fabric_name,
1899	pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1900	pr_reg->pr_res_key, pr_reg->pr_res_type,
1901	pr_reg->pr_res_scope, pr_reg->pr_reg_all_tg_pt,
1902	pr_reg->pr_res_mapped_lun);
1903	} else {
1904	snprintf(buf: tmp, size: 512, fmt: "PR_REG_START: %d\n"
1905	"initiator_fabric=%s\ninitiator_node=%s\n%s"
1906	"sa_res_key=%llu\nres_holder=0\n"
1907	"res_all_tg_pt=%d\nmapped_lun=%llu\n",
1908	reg_count, tpg->se_tpg_tfo->fabric_name,
1909	pr_reg->pr_reg_nacl->initiatorname, isid_buf,
1910	pr_reg->pr_res_key, pr_reg->pr_reg_all_tg_pt,
1911	pr_reg->pr_res_mapped_lun);
1912	}
1913
1914	if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1915	pr_err("Unable to update renaming APTPL metadata,"
1916	" reallocating larger buffer\n");
1917	ret = -EMSGSIZE;
1918	goto out;
1919	}
1920	len += sprintf(buf: buf+len, fmt: "%s", tmp);
1921
1922	/*
1923	* Include information about the associated SCSI target port.
1924	*/
1925	snprintf(buf: tmp, size: 512, fmt: "target_fabric=%s\ntarget_node=%s\n"
1926	"tpgt=%hu\nport_rtpi=%hu\ntarget_lun=%llu\nPR_REG_END:"
1927	" %d\n", tpg->se_tpg_tfo->fabric_name,
1928	tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1929	tpg->se_tpg_tfo->tpg_get_tag(tpg),
1930	pr_reg->tg_pt_sep_rtpi, pr_reg->pr_aptpl_target_lun,
1931	reg_count);
1932
1933	if ((len + strlen(tmp) >= pr_aptpl_buf_len)) {
1934	pr_err("Unable to update renaming APTPL metadata,"
1935	" reallocating larger buffer\n");
1936	ret = -EMSGSIZE;
1937	goto out;
1938	}
1939	len += sprintf(buf: buf+len, fmt: "%s", tmp);
1940	reg_count++;
1941	}
1942
1943	if (!reg_count)
1944	len += sprintf(buf: buf+len, fmt: "No Registrations or Reservations");
1945
1946	out:
1947	spin_unlock(lock: &dev->t10_pr.registration_lock);
1948	spin_unlock(lock: &dev->dev_reservation_lock);
1949
1950	return ret;
1951	}
1952
1953	static int __core_scsi3_write_aptpl_to_file(
1954	struct se_device *dev,
1955	unsigned char *buf)
1956	{
1957	struct t10_wwn *wwn = &dev->t10_wwn;
1958	struct file *file;
1959	int flags = O_RDWR | O_CREAT | O_TRUNC;
1960	char *path;
1961	u32 pr_aptpl_buf_len;
1962	int ret;
1963	loff_t pos = 0;
1964
1965	path = kasprintf(GFP_KERNEL, fmt: "%s/pr/aptpl_%s", db_root,
1966	&wwn->unit_serial[0]);
1967	if (!path)
1968	return -ENOMEM;
1969
1970	file = filp_open(path, flags, 0600);
1971	if (IS_ERR(ptr: file)) {
1972	pr_err("filp_open(%s) for APTPL metadata"
1973	" failed\n", path);
1974	kfree(objp: path);
1975	return PTR_ERR(ptr: file);
1976	}
1977
1978	pr_aptpl_buf_len = (strlen(buf) + 1); /* Add extra for NULL */
1979
1980	ret = kernel_write(file, buf, pr_aptpl_buf_len, &pos);
1981
1982	if (ret < 0)
1983	pr_debug("Error writing APTPL metadata file: %s\n", path);
1984	fput(file);
1985	kfree(objp: path);
1986
1987	return (ret < 0) ? -EIO : 0;
1988	}
1989
1990	/*
1991	* Clear the APTPL metadata if APTPL has been disabled, otherwise
1992	* write out the updated metadata to struct file for this SCSI device.
1993	*/
1994	static sense_reason_t core_scsi3_update_and_write_aptpl(struct se_device *dev, bool aptpl)
1995	{
1996	unsigned char *buf;
1997	int rc, len = PR_APTPL_BUF_LEN;
1998
1999	if (!aptpl) {
2000	char *null_buf = "No Registrations or Reservations\n";
2001
2002	rc = __core_scsi3_write_aptpl_to_file(dev, buf: null_buf);
2003	dev->t10_pr.pr_aptpl_active = 0;
2004	pr_debug("SPC-3 PR: Set APTPL Bit Deactivated\n");
2005
2006	if (rc)
2007	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2008
2009	return 0;
2010	}
2011	retry:
2012	buf = vzalloc(size: len);
2013	if (!buf)
2014	return TCM_OUT_OF_RESOURCES;
2015
2016	rc = core_scsi3_update_aptpl_buf(dev, buf, pr_aptpl_buf_len: len);
2017	if (rc < 0) {
2018	vfree(addr: buf);
2019	len *= 2;
2020	goto retry;
2021	}
2022
2023	rc = __core_scsi3_write_aptpl_to_file(dev, buf);
2024	if (rc != 0) {
2025	pr_err("SPC-3 PR: Could not update APTPL\n");
2026	vfree(addr: buf);
2027	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2028	}
2029	dev->t10_pr.pr_aptpl_active = 1;
2030	vfree(addr: buf);
2031	pr_debug("SPC-3 PR: Set APTPL Bit Activated\n");
2032	return 0;
2033	}
2034
2035	static sense_reason_t
2036	core_scsi3_emulate_pro_register(struct se_cmd *cmd, u64 res_key, u64 sa_res_key,
2037	bool aptpl, bool all_tg_pt, bool spec_i_pt, enum register_type register_type)
2038	{
2039	struct se_session *se_sess = cmd->se_sess;
2040	struct se_device *dev = cmd->se_dev;
2041	struct se_lun *se_lun = cmd->se_lun;
2042	struct se_portal_group *se_tpg;
2043	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_reg_tmp;
2044	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2045	unsigned char isid_buf[PR_REG_ISID_LEN] = { };
2046	unsigned char *isid_ptr = NULL;
2047	sense_reason_t ret = TCM_NO_SENSE;
2048	int pr_holder = 0, type;
2049
2050	if (!se_sess || !se_lun) {
2051	pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2052	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2053	}
2054	se_tpg = se_sess->se_tpg;
2055
2056	if (se_tpg->se_tpg_tfo->sess_get_initiator_sid) {
2057	se_tpg->se_tpg_tfo->sess_get_initiator_sid(se_sess, &isid_buf[0],
2058	PR_REG_ISID_LEN);
2059	isid_ptr = &isid_buf[0];
2060	}
2061	/*
2062	* Follow logic from spc4r17 Section 5.7.7, Register Behaviors Table 47
2063	*/
2064	pr_reg = core_scsi3_locate_pr_reg(dev, nacl: se_sess->se_node_acl, sess: se_sess);
2065	if (!pr_reg) {
2066	if (res_key) {
2067	pr_warn("SPC-3 PR: Reservation Key non-zero"
2068	" for SA REGISTER, returning CONFLICT\n");
2069	return TCM_RESERVATION_CONFLICT;
2070	}
2071	/*
2072	* Do nothing but return GOOD status.
2073	*/
2074	if (!sa_res_key)
2075	return 0;
2076
2077	if (!spec_i_pt) {
2078	/*
2079	* Perform the Service Action REGISTER on the Initiator
2080	* Port Endpoint that the PRO was received from on the
2081	* Logical Unit of the SCSI device server.
2082	*/
2083	if (core_scsi3_alloc_registration(dev: cmd->se_dev,
2084	nacl: se_sess->se_node_acl, lun: cmd->se_lun,
2085	NULL, mapped_lun: cmd->orig_fe_lun, isid: isid_ptr,
2086	sa_res_key, all_tg_pt, aptpl,
2087	register_type, register_move: 0)) {
2088	pr_err("Unable to allocate"
2089	" struct t10_pr_registration\n");
2090	return TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
2091	}
2092	} else {
2093	/*
2094	* Register both the Initiator port that received
2095	* PROUT SA REGISTER + SPEC_I_PT=1 and extract SCSI
2096	* TransportID from Parameter list and loop through
2097	* fabric dependent parameter list while calling
2098	* logic from of core_scsi3_alloc_registration() for
2099	* each TransportID provided SCSI Initiator Port/Device
2100	*/
2101	ret = core_scsi3_decode_spec_i_port(cmd, tpg: se_tpg,
2102	l_isid: isid_ptr, sa_res_key, all_tg_pt, aptpl);
2103	if (ret != 0)
2104	return ret;
2105	}
2106	return core_scsi3_update_and_write_aptpl(dev, aptpl);
2107	}
2108
2109	/* ok, existing registration */
2110
2111	if ((register_type == REGISTER) && (res_key != pr_reg->pr_res_key)) {
2112	pr_err("SPC-3 PR REGISTER: Received"
2113	" res_key: 0x%016Lx does not match"
2114	" existing SA REGISTER res_key:"
2115	" 0x%016Lx\n", res_key,
2116	pr_reg->pr_res_key);
2117	ret = TCM_RESERVATION_CONFLICT;
2118	goto out;
2119	}
2120
2121	if (spec_i_pt) {
2122	pr_err("SPC-3 PR REGISTER: SPEC_I_PT"
2123	" set on a registered nexus\n");
2124	ret = TCM_INVALID_PARAMETER_LIST;
2125	goto out;
2126	}
2127
2128	/*
2129	* An existing ALL_TG_PT=1 registration being released
2130	* must also set ALL_TG_PT=1 in the incoming PROUT.
2131	*/
2132	if (pr_reg->pr_reg_all_tg_pt && !all_tg_pt) {
2133	pr_err("SPC-3 PR REGISTER: ALL_TG_PT=1"
2134	" registration exists, but ALL_TG_PT=1 bit not"
2135	" present in received PROUT\n");
2136	ret = TCM_INVALID_CDB_FIELD;
2137	goto out;
2138	}
2139
2140	/*
2141	* sa_res_key=1 Change Reservation Key for registered I_T Nexus.
2142	*/
2143	if (sa_res_key) {
2144	/*
2145	* Increment PRgeneration counter for struct se_device"
2146	* upon a successful REGISTER, see spc4r17 section 6.3.2
2147	* READ_KEYS service action.
2148	*/
2149	pr_reg->pr_res_generation = core_scsi3_pr_generation(dev: cmd->se_dev);
2150	pr_reg->pr_res_key = sa_res_key;
2151	pr_debug("SPC-3 PR [%s] REGISTER%s: Changed Reservation"
2152	" Key for %s to: 0x%016Lx PRgeneration:"
2153	" 0x%08x\n", cmd->se_tfo->fabric_name,
2154	(register_type == REGISTER_AND_IGNORE_EXISTING_KEY) ? "_AND_IGNORE_EXISTING_KEY" : "",
2155	pr_reg->pr_reg_nacl->initiatorname,
2156	pr_reg->pr_res_key, pr_reg->pr_res_generation);
2157
2158	} else {
2159	/*
2160	* sa_res_key=0 Unregister Reservation Key for registered I_T Nexus.
2161	*/
2162	type = pr_reg->pr_res_type;
2163	pr_holder = core_scsi3_check_implicit_release(dev: cmd->se_dev,
2164	pr_reg);
2165	if (pr_holder < 0) {
2166	ret = TCM_RESERVATION_CONFLICT;
2167	goto out;
2168	}
2169
2170	spin_lock(lock: &pr_tmpl->registration_lock);
2171	/*
2172	* Release all ALL_TG_PT=1 for the matching SCSI Initiator Port
2173	* and matching pr_res_key.
2174	*/
2175	if (pr_reg->pr_reg_all_tg_pt) {
2176	list_for_each_entry_safe(pr_reg_p, pr_reg_tmp,
2177	&pr_tmpl->registration_list,
2178	pr_reg_list) {
2179
2180	if (!pr_reg_p->pr_reg_all_tg_pt)
2181	continue;
2182	if (pr_reg_p->pr_res_key != res_key)
2183	continue;
2184	if (pr_reg == pr_reg_p)
2185	continue;
2186	if (strcmp(pr_reg->pr_reg_nacl->initiatorname,
2187	pr_reg_p->pr_reg_nacl->initiatorname))
2188	continue;
2189
2190	__core_scsi3_free_registration(dev,
2191	pr_reg: pr_reg_p, NULL, dec_holders: 0);
2192	}
2193	}
2194
2195	/*
2196	* Release the calling I_T Nexus registration now..
2197	*/
2198	__core_scsi3_free_registration(dev: cmd->se_dev, pr_reg, NULL, dec_holders: 1);
2199	pr_reg = NULL;
2200
2201	/*
2202	* From spc4r17, section 5.7.11.3 Unregistering
2203	*
2204	* If the persistent reservation is a registrants only
2205	* type, the device server shall establish a unit
2206	* attention condition for the initiator port associated
2207	* with every registered I_T nexus except for the I_T
2208	* nexus on which the PERSISTENT RESERVE OUT command was
2209	* received, with the additional sense code set to
2210	* RESERVATIONS RELEASED.
2211	*/
2212	if (pr_holder &&
2213	(type == PR_TYPE_WRITE_EXCLUSIVE_REGONLY ||
2214	type == PR_TYPE_EXCLUSIVE_ACCESS_REGONLY)) {
2215	list_for_each_entry(pr_reg_p,
2216	&pr_tmpl->registration_list,
2217	pr_reg_list) {
2218
2219	target_ua_allocate_lun(
2220	pr_reg_p->pr_reg_nacl,
2221	pr_reg_p->pr_res_mapped_lun,
2222	0x2A,
2223	ASCQ_2AH_RESERVATIONS_RELEASED);
2224	}
2225	}
2226
2227	spin_unlock(lock: &pr_tmpl->registration_lock);
2228	}
2229
2230	ret = core_scsi3_update_and_write_aptpl(dev, aptpl);
2231
2232	out:
2233	if (pr_reg)
2234	core_scsi3_put_pr_reg(pr_reg);
2235	return ret;
2236	}
2237
2238	unsigned char *core_scsi3_pr_dump_type(int type)
2239	{
2240	switch (type) {
2241	case PR_TYPE_WRITE_EXCLUSIVE:
2242	return "Write Exclusive Access";
2243	case PR_TYPE_EXCLUSIVE_ACCESS:
2244	return "Exclusive Access";
2245	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2246	return "Write Exclusive Access, Registrants Only";
2247	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2248	return "Exclusive Access, Registrants Only";
2249	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2250	return "Write Exclusive Access, All Registrants";
2251	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2252	return "Exclusive Access, All Registrants";
2253	default:
2254	break;
2255	}
2256
2257	return "Unknown SPC-3 PR Type";
2258	}
2259
2260	static sense_reason_t
2261	core_scsi3_pro_reserve(struct se_cmd *cmd, int type, int scope, u64 res_key)
2262	{
2263	struct se_device *dev = cmd->se_dev;
2264	struct se_session *se_sess = cmd->se_sess;
2265	struct se_lun *se_lun = cmd->se_lun;
2266	struct t10_pr_registration *pr_reg, *pr_res_holder;
2267	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2268	char i_buf[PR_REG_ISID_ID_LEN] = { };
2269	sense_reason_t ret;
2270
2271	if (!se_sess || !se_lun) {
2272	pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2273	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2274	}
2275	/*
2276	* Locate the existing *pr_reg via struct se_node_acl pointers
2277	*/
2278	pr_reg = core_scsi3_locate_pr_reg(dev: cmd->se_dev, nacl: se_sess->se_node_acl,
2279	sess: se_sess);
2280	if (!pr_reg) {
2281	pr_err("SPC-3 PR: Unable to locate"
2282	" PR_REGISTERED *pr_reg for RESERVE\n");
2283	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2284	}
2285	/*
2286	* From spc4r17 Section 5.7.9: Reserving:
2287	*
2288	* An application client creates a persistent reservation by issuing
2289	* a PERSISTENT RESERVE OUT command with RESERVE service action through
2290	* a registered I_T nexus with the following parameters:
2291	* a) RESERVATION KEY set to the value of the reservation key that is
2292	* registered with the logical unit for the I_T nexus; and
2293	*/
2294	if (res_key != pr_reg->pr_res_key) {
2295	pr_err("SPC-3 PR RESERVE: Received res_key: 0x%016Lx"
2296	" does not match existing SA REGISTER res_key:"
2297	" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2298	ret = TCM_RESERVATION_CONFLICT;
2299	goto out_put_pr_reg;
2300	}
2301	/*
2302	* From spc4r17 Section 5.7.9: Reserving:
2303	*
2304	* From above:
2305	* b) TYPE field and SCOPE field set to the persistent reservation
2306	* being created.
2307	*
2308	* Only one persistent reservation is allowed at a time per logical unit
2309	* and that persistent reservation has a scope of LU_SCOPE.
2310	*/
2311	if (scope != PR_SCOPE_LU_SCOPE) {
2312	pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2313	ret = TCM_INVALID_PARAMETER_LIST;
2314	goto out_put_pr_reg;
2315	}
2316	/*
2317	* See if we have an existing PR reservation holder pointer at
2318	* struct se_device->dev_pr_res_holder in the form struct t10_pr_registration
2319	* *pr_res_holder.
2320	*/
2321	spin_lock(lock: &dev->dev_reservation_lock);
2322	pr_res_holder = dev->dev_pr_res_holder;
2323	if (pr_res_holder) {
2324	/*
2325	* From spc4r17 Section 5.7.9: Reserving:
2326	*
2327	* If the device server receives a PERSISTENT RESERVE OUT
2328	* command from an I_T nexus other than a persistent reservation
2329	* holder (see 5.7.10) that attempts to create a persistent
2330	* reservation when a persistent reservation already exists for
2331	* the logical unit, then the command shall be completed with
2332	* RESERVATION CONFLICT status.
2333	*/
2334	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2335	struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2336	pr_err("SPC-3 PR: Attempted RESERVE from"
2337	" [%s]: %s while reservation already held by"
2338	" [%s]: %s, returning RESERVATION_CONFLICT\n",
2339	cmd->se_tfo->fabric_name,
2340	se_sess->se_node_acl->initiatorname,
2341	pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2342	pr_res_holder->pr_reg_nacl->initiatorname);
2343
2344	spin_unlock(lock: &dev->dev_reservation_lock);
2345	ret = TCM_RESERVATION_CONFLICT;
2346	goto out_put_pr_reg;
2347	}
2348	/*
2349	* From spc4r17 Section 5.7.9: Reserving:
2350	*
2351	* If a persistent reservation holder attempts to modify the
2352	* type or scope of an existing persistent reservation, the
2353	* command shall be completed with RESERVATION CONFLICT status.
2354	*/
2355	if ((pr_res_holder->pr_res_type != type) ||
2356	(pr_res_holder->pr_res_scope != scope)) {
2357	struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2358	pr_err("SPC-3 PR: Attempted RESERVE from"
2359	" [%s]: %s trying to change TYPE and/or SCOPE,"
2360	" while reservation already held by [%s]: %s,"
2361	" returning RESERVATION_CONFLICT\n",
2362	cmd->se_tfo->fabric_name,
2363	se_sess->se_node_acl->initiatorname,
2364	pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2365	pr_res_holder->pr_reg_nacl->initiatorname);
2366
2367	spin_unlock(lock: &dev->dev_reservation_lock);
2368	ret = TCM_RESERVATION_CONFLICT;
2369	goto out_put_pr_reg;
2370	}
2371	/*
2372	* From spc4r17 Section 5.7.9: Reserving:
2373	*
2374	* If the device server receives a PERSISTENT RESERVE OUT
2375	* command with RESERVE service action where the TYPE field and
2376	* the SCOPE field contain the same values as the existing type
2377	* and scope from a persistent reservation holder, it shall not
2378	* make any change to the existing persistent reservation and
2379	* shall completethe command with GOOD status.
2380	*/
2381	spin_unlock(lock: &dev->dev_reservation_lock);
2382	ret = 0;
2383	goto out_put_pr_reg;
2384	}
2385	/*
2386	* Otherwise, our *pr_reg becomes the PR reservation holder for said
2387	* TYPE/SCOPE. Also set the received scope and type in *pr_reg.
2388	*/
2389	pr_reg->pr_res_scope = scope;
2390	pr_reg->pr_res_type = type;
2391	pr_reg->pr_res_holder = 1;
2392	dev->dev_pr_res_holder = pr_reg;
2393	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
2394
2395	pr_debug("SPC-3 PR [%s] Service Action: RESERVE created new"
2396	" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2397	cmd->se_tfo->fabric_name, core_scsi3_pr_dump_type(type),
2398	(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2399	pr_debug("SPC-3 PR [%s] RESERVE Node: %s%s\n",
2400	cmd->se_tfo->fabric_name,
2401	se_sess->se_node_acl->initiatorname,
2402	i_buf);
2403	spin_unlock(lock: &dev->dev_reservation_lock);
2404
2405	if (pr_tmpl->pr_aptpl_active)
2406	core_scsi3_update_and_write_aptpl(dev: cmd->se_dev, aptpl: true);
2407
2408	ret = 0;
2409	out_put_pr_reg:
2410	core_scsi3_put_pr_reg(pr_reg);
2411	return ret;
2412	}
2413
2414	static sense_reason_t
2415	core_scsi3_emulate_pro_reserve(struct se_cmd *cmd, int type, int scope,
2416	u64 res_key)
2417	{
2418	switch (type) {
2419	case PR_TYPE_WRITE_EXCLUSIVE:
2420	case PR_TYPE_EXCLUSIVE_ACCESS:
2421	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
2422	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
2423	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
2424	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
2425	return core_scsi3_pro_reserve(cmd, type, scope, res_key);
2426	default:
2427	pr_err("SPC-3 PR: Unknown Service Action RESERVE Type:"
2428	" 0x%02x\n", type);
2429	return TCM_INVALID_CDB_FIELD;
2430	}
2431	}
2432
2433	static void __core_scsi3_complete_pro_release(
2434	struct se_device *dev,
2435	struct se_node_acl *se_nacl,
2436	struct t10_pr_registration *pr_reg,
2437	int explicit,
2438	int unreg)
2439	{
2440	const struct target_core_fabric_ops *tfo = se_nacl->se_tpg->se_tpg_tfo;
2441	char i_buf[PR_REG_ISID_ID_LEN] = { };
2442	int pr_res_type = 0, pr_res_scope = 0;
2443
2444	lockdep_assert_held(&dev->dev_reservation_lock);
2445
2446	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
2447	/*
2448	* Go ahead and release the current PR reservation holder.
2449	* If an All Registrants reservation is currently active and
2450	* a unregister operation is requested, replace the current
2451	* dev_pr_res_holder with another active registration.
2452	*/
2453	if (dev->dev_pr_res_holder) {
2454	pr_res_type = dev->dev_pr_res_holder->pr_res_type;
2455	pr_res_scope = dev->dev_pr_res_holder->pr_res_scope;
2456	dev->dev_pr_res_holder->pr_res_type = 0;
2457	dev->dev_pr_res_holder->pr_res_scope = 0;
2458	dev->dev_pr_res_holder->pr_res_holder = 0;
2459	dev->dev_pr_res_holder = NULL;
2460	}
2461	if (!unreg)
2462	goto out;
2463
2464	spin_lock(lock: &dev->t10_pr.registration_lock);
2465	list_del_init(entry: &pr_reg->pr_reg_list);
2466	/*
2467	* If the I_T nexus is a reservation holder, the persistent reservation
2468	* is of an all registrants type, and the I_T nexus is the last remaining
2469	* registered I_T nexus, then the device server shall also release the
2470	* persistent reservation.
2471	*/
2472	if (!list_empty(head: &dev->t10_pr.registration_list) &&
2473	((pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2474	(pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))) {
2475	dev->dev_pr_res_holder =
2476	list_entry(dev->t10_pr.registration_list.next,
2477	struct t10_pr_registration, pr_reg_list);
2478	dev->dev_pr_res_holder->pr_res_type = pr_res_type;
2479	dev->dev_pr_res_holder->pr_res_scope = pr_res_scope;
2480	dev->dev_pr_res_holder->pr_res_holder = 1;
2481	}
2482	spin_unlock(lock: &dev->t10_pr.registration_lock);
2483	out:
2484	if (!dev->dev_pr_res_holder) {
2485	pr_debug("SPC-3 PR [%s] Service Action: %s RELEASE cleared"
2486	" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2487	tfo->fabric_name, (explicit) ? "explicit" :
2488	"implicit", core_scsi3_pr_dump_type(pr_res_type),
2489	(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2490	}
2491	pr_debug("SPC-3 PR [%s] RELEASE Node: %s%s\n",
2492	tfo->fabric_name, se_nacl->initiatorname,
2493	i_buf);
2494	/*
2495	* Clear TYPE and SCOPE for the next PROUT Service Action: RESERVE
2496	*/
2497	pr_reg->pr_res_holder = pr_reg->pr_res_type = pr_reg->pr_res_scope = 0;
2498	}
2499
2500	static sense_reason_t
2501	core_scsi3_emulate_pro_release(struct se_cmd *cmd, int type, int scope,
2502	u64 res_key)
2503	{
2504	struct se_device *dev = cmd->se_dev;
2505	struct se_session *se_sess = cmd->se_sess;
2506	struct se_lun *se_lun = cmd->se_lun;
2507	struct t10_pr_registration *pr_reg, *pr_reg_p, *pr_res_holder;
2508	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2509	sense_reason_t ret = 0;
2510
2511	if (!se_sess || !se_lun) {
2512	pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
2513	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2514	}
2515	/*
2516	* Locate the existing *pr_reg via struct se_node_acl pointers
2517	*/
2518	pr_reg = core_scsi3_locate_pr_reg(dev, nacl: se_sess->se_node_acl, sess: se_sess);
2519	if (!pr_reg) {
2520	pr_err("SPC-3 PR: Unable to locate"
2521	" PR_REGISTERED *pr_reg for RELEASE\n");
2522	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2523	}
2524	/*
2525	* From spc4r17 Section 5.7.11.2 Releasing:
2526	*
2527	* If there is no persistent reservation or in response to a persistent
2528	* reservation release request from a registered I_T nexus that is not a
2529	* persistent reservation holder (see 5.7.10), the device server shall
2530	* do the following:
2531	*
2532	* a) Not release the persistent reservation, if any;
2533	* b) Not remove any registrations; and
2534	* c) Complete the command with GOOD status.
2535	*/
2536	spin_lock(lock: &dev->dev_reservation_lock);
2537	pr_res_holder = dev->dev_pr_res_holder;
2538	if (!pr_res_holder) {
2539	/*
2540	* No persistent reservation, return GOOD status.
2541	*/
2542	spin_unlock(lock: &dev->dev_reservation_lock);
2543	goto out_put_pr_reg;
2544	}
2545
2546	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
2547	/*
2548	* Release request from a registered I_T nexus that is not a
2549	* persistent reservation holder. return GOOD status.
2550	*/
2551	spin_unlock(lock: &dev->dev_reservation_lock);
2552	goto out_put_pr_reg;
2553	}
2554
2555	/*
2556	* From spc4r17 Section 5.7.11.2 Releasing:
2557	*
2558	* Only the persistent reservation holder (see 5.7.10) is allowed to
2559	* release a persistent reservation.
2560	*
2561	* An application client releases the persistent reservation by issuing
2562	* a PERSISTENT RESERVE OUT command with RELEASE service action through
2563	* an I_T nexus that is a persistent reservation holder with the
2564	* following parameters:
2565	*
2566	* a) RESERVATION KEY field set to the value of the reservation key
2567	* that is registered with the logical unit for the I_T nexus;
2568	*/
2569	if (res_key != pr_reg->pr_res_key) {
2570	pr_err("SPC-3 PR RELEASE: Received res_key: 0x%016Lx"
2571	" does not match existing SA REGISTER res_key:"
2572	" 0x%016Lx\n", res_key, pr_reg->pr_res_key);
2573	spin_unlock(lock: &dev->dev_reservation_lock);
2574	ret = TCM_RESERVATION_CONFLICT;
2575	goto out_put_pr_reg;
2576	}
2577	/*
2578	* From spc4r17 Section 5.7.11.2 Releasing and above:
2579	*
2580	* b) TYPE field and SCOPE field set to match the persistent
2581	* reservation being released.
2582	*/
2583	if ((pr_res_holder->pr_res_type != type) ||
2584	(pr_res_holder->pr_res_scope != scope)) {
2585	struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2586	pr_err("SPC-3 PR RELEASE: Attempted to release"
2587	" reservation from [%s]: %s with different TYPE "
2588	"and/or SCOPE while reservation already held by"
2589	" [%s]: %s, returning RESERVATION_CONFLICT\n",
2590	cmd->se_tfo->fabric_name,
2591	se_sess->se_node_acl->initiatorname,
2592	pr_res_nacl->se_tpg->se_tpg_tfo->fabric_name,
2593	pr_res_holder->pr_reg_nacl->initiatorname);
2594
2595	spin_unlock(lock: &dev->dev_reservation_lock);
2596	ret = TCM_RESERVATION_CONFLICT;
2597	goto out_put_pr_reg;
2598	}
2599	/*
2600	* In response to a persistent reservation release request from the
2601	* persistent reservation holder the device server shall perform a
2602	* release by doing the following as an uninterrupted series of actions:
2603	* a) Release the persistent reservation;
2604	* b) Not remove any registration(s);
2605	* c) If the released persistent reservation is a registrants only type
2606	* or all registrants type persistent reservation,
2607	* the device server shall establish a unit attention condition for
2608	* the initiator port associated with every regis-
2609	* tered I_T nexus other than I_T nexus on which the PERSISTENT
2610	* RESERVE OUT command with RELEASE service action was received,
2611	* with the additional sense code set to RESERVATIONS RELEASED; and
2612	* d) If the persistent reservation is of any other type, the device
2613	* server shall not establish a unit attention condition.
2614	*/
2615	__core_scsi3_complete_pro_release(dev, se_nacl: se_sess->se_node_acl,
2616	pr_reg, explicit: 1, unreg: 0);
2617
2618	spin_unlock(lock: &dev->dev_reservation_lock);
2619
2620	if ((type != PR_TYPE_WRITE_EXCLUSIVE_REGONLY) &&
2621	(type != PR_TYPE_EXCLUSIVE_ACCESS_REGONLY) &&
2622	(type != PR_TYPE_WRITE_EXCLUSIVE_ALLREG) &&
2623	(type != PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
2624	/*
2625	* If no UNIT ATTENTION conditions will be established for
2626	* PR_TYPE_WRITE_EXCLUSIVE or PR_TYPE_EXCLUSIVE_ACCESS
2627	* go ahead and check for APTPL=1 update+write below
2628	*/
2629	goto write_aptpl;
2630	}
2631
2632	spin_lock(lock: &pr_tmpl->registration_lock);
2633	list_for_each_entry(pr_reg_p, &pr_tmpl->registration_list,
2634	pr_reg_list) {
2635	/*
2636	* Do not establish a UNIT ATTENTION condition
2637	* for the calling I_T Nexus
2638	*/
2639	if (pr_reg_p == pr_reg)
2640	continue;
2641
2642	target_ua_allocate_lun(pr_reg_p->pr_reg_nacl,
2643	pr_reg_p->pr_res_mapped_lun,
2644	0x2A, ASCQ_2AH_RESERVATIONS_RELEASED);
2645	}
2646	spin_unlock(lock: &pr_tmpl->registration_lock);
2647
2648	write_aptpl:
2649	if (pr_tmpl->pr_aptpl_active)
2650	core_scsi3_update_and_write_aptpl(dev: cmd->se_dev, aptpl: true);
2651
2652	out_put_pr_reg:
2653	core_scsi3_put_pr_reg(pr_reg);
2654	return ret;
2655	}
2656
2657	static sense_reason_t
2658	core_scsi3_emulate_pro_clear(struct se_cmd *cmd, u64 res_key)
2659	{
2660	struct se_device *dev = cmd->se_dev;
2661	struct se_node_acl *pr_reg_nacl;
2662	struct se_session *se_sess = cmd->se_sess;
2663	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2664	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2665	u64 pr_res_mapped_lun = 0;
2666	int calling_it_nexus = 0;
2667	/*
2668	* Locate the existing *pr_reg via struct se_node_acl pointers
2669	*/
2670	pr_reg_n = core_scsi3_locate_pr_reg(dev: cmd->se_dev,
2671	nacl: se_sess->se_node_acl, sess: se_sess);
2672	if (!pr_reg_n) {
2673	pr_err("SPC-3 PR: Unable to locate"
2674	" PR_REGISTERED *pr_reg for CLEAR\n");
2675	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2676	}
2677	/*
2678	* From spc4r17 section 5.7.11.6, Clearing:
2679	*
2680	* Any application client may release the persistent reservation and
2681	* remove all registrations from a device server by issuing a
2682	* PERSISTENT RESERVE OUT command with CLEAR service action through a
2683	* registered I_T nexus with the following parameter:
2684	*
2685	* a) RESERVATION KEY field set to the value of the reservation key
2686	* that is registered with the logical unit for the I_T nexus.
2687	*/
2688	if (res_key != pr_reg_n->pr_res_key) {
2689	pr_err("SPC-3 PR REGISTER: Received"
2690	" res_key: 0x%016Lx does not match"
2691	" existing SA REGISTER res_key:"
2692	" 0x%016Lx\n", res_key, pr_reg_n->pr_res_key);
2693	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
2694	return TCM_RESERVATION_CONFLICT;
2695	}
2696	/*
2697	* a) Release the persistent reservation, if any;
2698	*/
2699	spin_lock(lock: &dev->dev_reservation_lock);
2700	pr_res_holder = dev->dev_pr_res_holder;
2701	if (pr_res_holder) {
2702	struct se_node_acl *pr_res_nacl = pr_res_holder->pr_reg_nacl;
2703	__core_scsi3_complete_pro_release(dev, se_nacl: pr_res_nacl,
2704	pr_reg: pr_res_holder, explicit: 0, unreg: 0);
2705	}
2706	spin_unlock(lock: &dev->dev_reservation_lock);
2707	/*
2708	* b) Remove all registration(s) (see spc4r17 5.7.7);
2709	*/
2710	spin_lock(lock: &pr_tmpl->registration_lock);
2711	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2712	&pr_tmpl->registration_list, pr_reg_list) {
2713
2714	calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2715	pr_reg_nacl = pr_reg->pr_reg_nacl;
2716	pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2717	__core_scsi3_free_registration(dev, pr_reg, NULL,
2718	dec_holders: calling_it_nexus);
2719	/*
2720	* e) Establish a unit attention condition for the initiator
2721	* port associated with every registered I_T nexus other
2722	* than the I_T nexus on which the PERSISTENT RESERVE OUT
2723	* command with CLEAR service action was received, with the
2724	* additional sense code set to RESERVATIONS PREEMPTED.
2725	*/
2726	if (!calling_it_nexus)
2727	target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun,
2728	0x2A, ASCQ_2AH_RESERVATIONS_PREEMPTED);
2729	}
2730	spin_unlock(lock: &pr_tmpl->registration_lock);
2731
2732	pr_debug("SPC-3 PR [%s] Service Action: CLEAR complete\n",
2733	cmd->se_tfo->fabric_name);
2734
2735	core_scsi3_update_and_write_aptpl(dev: cmd->se_dev, aptpl: false);
2736
2737	core_scsi3_pr_generation(dev);
2738	return 0;
2739	}
2740
2741	static void __core_scsi3_complete_pro_preempt(
2742	struct se_device *dev,
2743	struct t10_pr_registration *pr_reg,
2744	struct list_head *preempt_and_abort_list,
2745	int type,
2746	int scope,
2747	enum preempt_type preempt_type)
2748	{
2749	struct se_node_acl *nacl = pr_reg->pr_reg_nacl;
2750	const struct target_core_fabric_ops *tfo = nacl->se_tpg->se_tpg_tfo;
2751	char i_buf[PR_REG_ISID_ID_LEN] = { };
2752
2753	lockdep_assert_held(&dev->dev_reservation_lock);
2754
2755	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
2756	/*
2757	* Do an implicit RELEASE of the existing reservation.
2758	*/
2759	if (dev->dev_pr_res_holder)
2760	__core_scsi3_complete_pro_release(dev, se_nacl: nacl,
2761	pr_reg: dev->dev_pr_res_holder, explicit: 0, unreg: 0);
2762
2763	dev->dev_pr_res_holder = pr_reg;
2764	pr_reg->pr_res_holder = 1;
2765	pr_reg->pr_res_type = type;
2766	pr_reg->pr_res_scope = scope;
2767
2768	pr_debug("SPC-3 PR [%s] Service Action: PREEMPT%s created new"
2769	" reservation holder TYPE: %s ALL_TG_PT: %d\n",
2770	tfo->fabric_name, (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2771	core_scsi3_pr_dump_type(type),
2772	(pr_reg->pr_reg_all_tg_pt) ? 1 : 0);
2773	pr_debug("SPC-3 PR [%s] PREEMPT%s from Node: %s%s\n",
2774	tfo->fabric_name, (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "",
2775	nacl->initiatorname, i_buf);
2776	/*
2777	* For PREEMPT_AND_ABORT, add the preempting reservation's
2778	* struct t10_pr_registration to the list that will be compared
2779	* against received CDBs..
2780	*/
2781	if (preempt_and_abort_list)
2782	list_add_tail(new: &pr_reg->pr_reg_abort_list,
2783	head: preempt_and_abort_list);
2784	}
2785
2786	static void core_scsi3_release_preempt_and_abort(
2787	struct list_head *preempt_and_abort_list,
2788	struct t10_pr_registration *pr_reg_holder)
2789	{
2790	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
2791
2792	list_for_each_entry_safe(pr_reg, pr_reg_tmp, preempt_and_abort_list,
2793	pr_reg_abort_list) {
2794
2795	list_del(entry: &pr_reg->pr_reg_abort_list);
2796	if (pr_reg_holder == pr_reg)
2797	continue;
2798	if (pr_reg->pr_res_holder) {
2799	pr_warn("pr_reg->pr_res_holder still set\n");
2800	continue;
2801	}
2802
2803	pr_reg->pr_reg_deve = NULL;
2804	pr_reg->pr_reg_nacl = NULL;
2805	kmem_cache_free(s: t10_pr_reg_cache, objp: pr_reg);
2806	}
2807	}
2808
2809	static sense_reason_t
2810	core_scsi3_pro_preempt(struct se_cmd *cmd, int type, int scope, u64 res_key,
2811	u64 sa_res_key, enum preempt_type preempt_type)
2812	{
2813	struct se_device *dev = cmd->se_dev;
2814	struct se_node_acl *pr_reg_nacl;
2815	struct se_session *se_sess = cmd->se_sess;
2816	LIST_HEAD(preempt_and_abort_list);
2817	struct t10_pr_registration *pr_reg, *pr_reg_tmp, *pr_reg_n, *pr_res_holder;
2818	struct t10_reservation *pr_tmpl = &dev->t10_pr;
2819	u64 pr_res_mapped_lun = 0;
2820	int all_reg = 0, calling_it_nexus = 0;
2821	bool sa_res_key_unmatched = sa_res_key != 0;
2822	int prh_type = 0, prh_scope = 0;
2823
2824	if (!se_sess)
2825	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
2826
2827	pr_reg_n = core_scsi3_locate_pr_reg(dev: cmd->se_dev, nacl: se_sess->se_node_acl,
2828	sess: se_sess);
2829	if (!pr_reg_n) {
2830	pr_err("SPC-3 PR: Unable to locate"
2831	" PR_REGISTERED *pr_reg for PREEMPT%s\n",
2832	(preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "");
2833	return TCM_RESERVATION_CONFLICT;
2834	}
2835	if (pr_reg_n->pr_res_key != res_key) {
2836	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
2837	return TCM_RESERVATION_CONFLICT;
2838	}
2839	if (scope != PR_SCOPE_LU_SCOPE) {
2840	pr_err("SPC-3 PR: Illegal SCOPE: 0x%02x\n", scope);
2841	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
2842	return TCM_INVALID_PARAMETER_LIST;
2843	}
2844
2845	spin_lock(lock: &dev->dev_reservation_lock);
2846	pr_res_holder = dev->dev_pr_res_holder;
2847	if (pr_res_holder &&
2848	((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
2849	(pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)))
2850	all_reg = 1;
2851
2852	if (!all_reg && !sa_res_key) {
2853	spin_unlock(lock: &dev->dev_reservation_lock);
2854	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
2855	return TCM_INVALID_PARAMETER_LIST;
2856	}
2857	/*
2858	* From spc4r17, section 5.7.11.4.4 Removing Registrations:
2859	*
2860	* If the SERVICE ACTION RESERVATION KEY field does not identify a
2861	* persistent reservation holder or there is no persistent reservation
2862	* holder (i.e., there is no persistent reservation), then the device
2863	* server shall perform a preempt by doing the following in an
2864	* uninterrupted series of actions. (See below..)
2865	*/
2866	if (!pr_res_holder || (pr_res_holder->pr_res_key != sa_res_key)) {
2867	/*
2868	* No existing or SA Reservation Key matching reservations..
2869	*
2870	* PROUT SA PREEMPT with All Registrant type reservations are
2871	* allowed to be processed without a matching SA Reservation Key
2872	*/
2873	spin_lock(lock: &pr_tmpl->registration_lock);
2874	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
2875	&pr_tmpl->registration_list, pr_reg_list) {
2876	/*
2877	* Removing of registrations in non all registrants
2878	* type reservations without a matching SA reservation
2879	* key.
2880	*
2881	* a) Remove the registrations for all I_T nexuses
2882	* specified by the SERVICE ACTION RESERVATION KEY
2883	* field;
2884	* b) Ignore the contents of the SCOPE and TYPE fields;
2885	* c) Process tasks as defined in 5.7.1; and
2886	* d) Establish a unit attention condition for the
2887	* initiator port associated with every I_T nexus
2888	* that lost its registration other than the I_T
2889	* nexus on which the PERSISTENT RESERVE OUT command
2890	* was received, with the additional sense code set
2891	* to REGISTRATIONS PREEMPTED.
2892	*/
2893	if (!all_reg) {
2894	if (pr_reg->pr_res_key != sa_res_key)
2895	continue;
2896	sa_res_key_unmatched = false;
2897
2898	calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2899	pr_reg_nacl = pr_reg->pr_reg_nacl;
2900	pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2901	__core_scsi3_free_registration(dev, pr_reg,
2902	preempt_and_abort_list: (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2903	NULL, dec_holders: calling_it_nexus);
2904	} else {
2905	/*
2906	* Case for any existing all registrants type
2907	* reservation, follow logic in spc4r17 section
2908	* 5.7.11.4 Preempting, Table 52 and Figure 7.
2909	*
2910	* For a ZERO SA Reservation key, release
2911	* all other registrations and do an implicit
2912	* release of active persistent reservation.
2913	*
2914	* For a non-ZERO SA Reservation key, only
2915	* release the matching reservation key from
2916	* registrations.
2917	*/
2918	if ((sa_res_key) &&
2919	(pr_reg->pr_res_key != sa_res_key))
2920	continue;
2921	sa_res_key_unmatched = false;
2922
2923	calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
2924	if (calling_it_nexus)
2925	continue;
2926
2927	pr_reg_nacl = pr_reg->pr_reg_nacl;
2928	pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
2929	__core_scsi3_free_registration(dev, pr_reg,
2930	preempt_and_abort_list: (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list :
2931	NULL, dec_holders: 0);
2932	}
2933	if (!calling_it_nexus)
2934	target_ua_allocate_lun(pr_reg_nacl,
2935	pr_res_mapped_lun, 0x2A,
2936	ASCQ_2AH_REGISTRATIONS_PREEMPTED);
2937	}
2938	spin_unlock(lock: &pr_tmpl->registration_lock);
2939	/*
2940	* If a PERSISTENT RESERVE OUT with a PREEMPT service action or
2941	* a PREEMPT AND ABORT service action sets the SERVICE ACTION
2942	* RESERVATION KEY field to a value that does not match any
2943	* registered reservation key, then the device server shall
2944	* complete the command with RESERVATION CONFLICT status.
2945	*/
2946	if (sa_res_key_unmatched) {
2947	spin_unlock(lock: &dev->dev_reservation_lock);
2948	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
2949	return TCM_RESERVATION_CONFLICT;
2950	}
2951	/*
2952	* For an existing all registrants type reservation
2953	* with a zero SA rservation key, preempt the existing
2954	* reservation with the new PR type and scope.
2955	*/
2956	if (pr_res_holder && all_reg && !(sa_res_key)) {
2957	__core_scsi3_complete_pro_preempt(dev, pr_reg: pr_reg_n,
2958	preempt_and_abort_list: (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
2959	type, scope, preempt_type);
2960	}
2961
2962	spin_unlock(lock: &dev->dev_reservation_lock);
2963
2964	/*
2965	* SPC-4 5.12.11.2.6 Preempting and aborting
2966	* The actions described in this subclause shall be performed
2967	* for all I_T nexuses that are registered with the non-zero
2968	* SERVICE ACTION RESERVATION KEY value, without regard for
2969	* whether the preempted I_T nexuses hold the persistent
2970	* reservation. If the SERVICE ACTION RESERVATION KEY field is
2971	* set to zero and an all registrants persistent reservation is
2972	* present, the device server shall abort all commands for all
2973	* registered I_T nexuses.
2974	*/
2975	if (preempt_type == PREEMPT_AND_ABORT) {
2976	core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list,
2977	cmd);
2978	core_scsi3_release_preempt_and_abort(
2979	preempt_and_abort_list: &preempt_and_abort_list, pr_reg_holder: pr_reg_n);
2980	}
2981
2982	if (pr_tmpl->pr_aptpl_active)
2983	core_scsi3_update_and_write_aptpl(dev: cmd->se_dev, aptpl: true);
2984
2985	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
2986	core_scsi3_pr_generation(dev: cmd->se_dev);
2987	return 0;
2988	}
2989	/*
2990	* The PREEMPTing SA reservation key matches that of the
2991	* existing persistent reservation, first, we check if
2992	* we are preempting our own reservation.
2993	* From spc4r17, section 5.7.11.4.3 Preempting
2994	* persistent reservations and registration handling
2995	*
2996	* If an all registrants persistent reservation is not
2997	* present, it is not an error for the persistent
2998	* reservation holder to preempt itself (i.e., a
2999	* PERSISTENT RESERVE OUT with a PREEMPT service action
3000	* or a PREEMPT AND ABORT service action with the
3001	* SERVICE ACTION RESERVATION KEY value equal to the
3002	* persistent reservation holder's reservation key that
3003	* is received from the persistent reservation holder).
3004	* In that case, the device server shall establish the
3005	* new persistent reservation and maintain the
3006	* registration.
3007	*/
3008	prh_type = pr_res_holder->pr_res_type;
3009	prh_scope = pr_res_holder->pr_res_scope;
3010	/*
3011	* If the SERVICE ACTION RESERVATION KEY field identifies a
3012	* persistent reservation holder (see 5.7.10), the device
3013	* server shall perform a preempt by doing the following as
3014	* an uninterrupted series of actions:
3015	*
3016	* a) Release the persistent reservation for the holder
3017	* identified by the SERVICE ACTION RESERVATION KEY field;
3018	*/
3019	if (pr_reg_n != pr_res_holder)
3020	__core_scsi3_complete_pro_release(dev,
3021	se_nacl: pr_res_holder->pr_reg_nacl,
3022	pr_reg: dev->dev_pr_res_holder, explicit: 0, unreg: 0);
3023	/*
3024	* b) Remove the registrations for all I_T nexuses identified
3025	* by the SERVICE ACTION RESERVATION KEY field, except the
3026	* I_T nexus that is being used for the PERSISTENT RESERVE
3027	* OUT command. If an all registrants persistent reservation
3028	* is present and the SERVICE ACTION RESERVATION KEY field
3029	* is set to zero, then all registrations shall be removed
3030	* except for that of the I_T nexus that is being used for
3031	* the PERSISTENT RESERVE OUT command;
3032	*/
3033	spin_lock(lock: &pr_tmpl->registration_lock);
3034	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3035	&pr_tmpl->registration_list, pr_reg_list) {
3036
3037	calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3038	if (calling_it_nexus)
3039	continue;
3040
3041	if (sa_res_key && pr_reg->pr_res_key != sa_res_key)
3042	continue;
3043
3044	pr_reg_nacl = pr_reg->pr_reg_nacl;
3045	pr_res_mapped_lun = pr_reg->pr_res_mapped_lun;
3046	__core_scsi3_free_registration(dev, pr_reg,
3047	preempt_and_abort_list: (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3048	dec_holders: calling_it_nexus);
3049	/*
3050	* e) Establish a unit attention condition for the initiator
3051	* port associated with every I_T nexus that lost its
3052	* persistent reservation and/or registration, with the
3053	* additional sense code set to REGISTRATIONS PREEMPTED;
3054	*/
3055	target_ua_allocate_lun(pr_reg_nacl, pr_res_mapped_lun, 0x2A,
3056	ASCQ_2AH_REGISTRATIONS_PREEMPTED);
3057	}
3058	spin_unlock(lock: &pr_tmpl->registration_lock);
3059	/*
3060	* c) Establish a persistent reservation for the preempting
3061	* I_T nexus using the contents of the SCOPE and TYPE fields;
3062	*/
3063	__core_scsi3_complete_pro_preempt(dev, pr_reg: pr_reg_n,
3064	preempt_and_abort_list: (preempt_type == PREEMPT_AND_ABORT) ? &preempt_and_abort_list : NULL,
3065	type, scope, preempt_type);
3066	/*
3067	* d) Process tasks as defined in 5.7.1;
3068	* e) See above..
3069	* f) If the type or scope has changed, then for every I_T nexus
3070	* whose reservation key was not removed, except for the I_T
3071	* nexus on which the PERSISTENT RESERVE OUT command was
3072	* received, the device server shall establish a unit
3073	* attention condition for the initiator port associated with
3074	* that I_T nexus, with the additional sense code set to
3075	* RESERVATIONS RELEASED. If the type or scope have not
3076	* changed, then no unit attention condition(s) shall be
3077	* established for this reason.
3078	*/
3079	if ((prh_type != type) || (prh_scope != scope)) {
3080	spin_lock(lock: &pr_tmpl->registration_lock);
3081	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3082	&pr_tmpl->registration_list, pr_reg_list) {
3083
3084	calling_it_nexus = (pr_reg_n == pr_reg) ? 1 : 0;
3085	if (calling_it_nexus)
3086	continue;
3087
3088	target_ua_allocate_lun(pr_reg->pr_reg_nacl,
3089	pr_reg->pr_res_mapped_lun, 0x2A,
3090	ASCQ_2AH_RESERVATIONS_RELEASED);
3091	}
3092	spin_unlock(lock: &pr_tmpl->registration_lock);
3093	}
3094	spin_unlock(lock: &dev->dev_reservation_lock);
3095	/*
3096	* Call LUN_RESET logic upon list of struct t10_pr_registration,
3097	* All received CDBs for the matching existing reservation and
3098	* registrations undergo ABORT_TASK logic.
3099	*
3100	* From there, core_scsi3_release_preempt_and_abort() will
3101	* release every registration in the list (which have already
3102	* been removed from the primary pr_reg list), except the
3103	* new persistent reservation holder, the calling Initiator Port.
3104	*/
3105	if (preempt_type == PREEMPT_AND_ABORT) {
3106	core_tmr_lun_reset(dev, NULL, &preempt_and_abort_list, cmd);
3107	core_scsi3_release_preempt_and_abort(preempt_and_abort_list: &preempt_and_abort_list,
3108	pr_reg_holder: pr_reg_n);
3109	}
3110
3111	if (pr_tmpl->pr_aptpl_active)
3112	core_scsi3_update_and_write_aptpl(dev: cmd->se_dev, aptpl: true);
3113
3114	core_scsi3_put_pr_reg(pr_reg: pr_reg_n);
3115	core_scsi3_pr_generation(dev: cmd->se_dev);
3116	return 0;
3117	}
3118
3119	static sense_reason_t
3120	core_scsi3_emulate_pro_preempt(struct se_cmd *cmd, int type, int scope,
3121	u64 res_key, u64 sa_res_key, enum preempt_type preempt_type)
3122	{
3123	switch (type) {
3124	case PR_TYPE_WRITE_EXCLUSIVE:
3125	case PR_TYPE_EXCLUSIVE_ACCESS:
3126	case PR_TYPE_WRITE_EXCLUSIVE_REGONLY:
3127	case PR_TYPE_EXCLUSIVE_ACCESS_REGONLY:
3128	case PR_TYPE_WRITE_EXCLUSIVE_ALLREG:
3129	case PR_TYPE_EXCLUSIVE_ACCESS_ALLREG:
3130	return core_scsi3_pro_preempt(cmd, type, scope, res_key,
3131	sa_res_key, preempt_type);
3132	default:
3133	pr_err("SPC-3 PR: Unknown Service Action PREEMPT%s"
3134	" Type: 0x%02x\n", (preempt_type == PREEMPT_AND_ABORT) ? "_AND_ABORT" : "", type);
3135	return TCM_INVALID_CDB_FIELD;
3136	}
3137	}
3138
3139
3140	static sense_reason_t
3141	core_scsi3_emulate_pro_register_and_move(struct se_cmd *cmd, u64 res_key,
3142	u64 sa_res_key, int aptpl, int unreg)
3143	{
3144	struct se_session *se_sess = cmd->se_sess;
3145	struct se_device *dev = cmd->se_dev;
3146	struct se_dev_entry *dest_se_deve = NULL;
3147	struct se_lun *se_lun = cmd->se_lun, *tmp_lun;
3148	struct se_node_acl *pr_res_nacl, *pr_reg_nacl, *dest_node_acl = NULL;
3149	struct se_portal_group *se_tpg, *dest_se_tpg = NULL;
3150	const struct target_core_fabric_ops *dest_tf_ops = NULL, *tf_ops;
3151	struct t10_pr_registration *pr_reg, *pr_res_holder, *dest_pr_reg;
3152	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3153	unsigned char *buf;
3154	const unsigned char *initiator_str;
3155	char *iport_ptr = NULL, i_buf[PR_REG_ISID_ID_LEN] = { };
3156	u32 tid_len, tmp_tid_len;
3157	int new_reg = 0, type, scope, matching_iname;
3158	sense_reason_t ret;
3159	unsigned short rtpi;
3160	unsigned char proto_ident;
3161
3162	if (!se_sess || !se_lun) {
3163	pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3164	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3165	}
3166
3167	se_tpg = se_sess->se_tpg;
3168	tf_ops = se_tpg->se_tpg_tfo;
3169	/*
3170	* Follow logic from spc4r17 Section 5.7.8, Table 50 --
3171	* Register behaviors for a REGISTER AND MOVE service action
3172	*
3173	* Locate the existing *pr_reg via struct se_node_acl pointers
3174	*/
3175	pr_reg = core_scsi3_locate_pr_reg(dev: cmd->se_dev, nacl: se_sess->se_node_acl,
3176	sess: se_sess);
3177	if (!pr_reg) {
3178	pr_err("SPC-3 PR: Unable to locate PR_REGISTERED"
3179	" *pr_reg for REGISTER_AND_MOVE\n");
3180	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3181	}
3182	/*
3183	* The provided reservation key much match the existing reservation key
3184	* provided during this initiator's I_T nexus registration.
3185	*/
3186	if (res_key != pr_reg->pr_res_key) {
3187	pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received"
3188	" res_key: 0x%016Lx does not match existing SA REGISTER"
3189	" res_key: 0x%016Lx\n", res_key, pr_reg->pr_res_key);
3190	ret = TCM_RESERVATION_CONFLICT;
3191	goto out_put_pr_reg;
3192	}
3193	/*
3194	* The service active reservation key needs to be non zero
3195	*/
3196	if (!sa_res_key) {
3197	pr_warn("SPC-3 PR REGISTER_AND_MOVE: Received zero"
3198	" sa_res_key\n");
3199	ret = TCM_INVALID_PARAMETER_LIST;
3200	goto out_put_pr_reg;
3201	}
3202
3203	/*
3204	* Determine the Relative Target Port Identifier where the reservation
3205	* will be moved to for the TransportID containing SCSI initiator WWN
3206	* information.
3207	*/
3208	buf = transport_kmap_data_sg(cmd);
3209	if (!buf) {
3210	ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3211	goto out_put_pr_reg;
3212	}
3213
3214	rtpi = get_unaligned_be16(p: &buf[18]);
3215	tid_len = get_unaligned_be32(p: &buf[20]);
3216	transport_kunmap_data_sg(cmd);
3217	buf = NULL;
3218
3219	if ((tid_len + 24) != cmd->data_length) {
3220	pr_err("SPC-3 PR: Illegal tid_len: %u + 24 byte header"
3221	" does not equal CDB data_length: %u\n", tid_len,
3222	cmd->data_length);
3223	ret = TCM_INVALID_PARAMETER_LIST;
3224	goto out_put_pr_reg;
3225	}
3226
3227	spin_lock(lock: &dev->se_port_lock);
3228	list_for_each_entry(tmp_lun, &dev->dev_sep_list, lun_dev_link) {
3229	if (tmp_lun->lun_tpg->tpg_rtpi != rtpi)
3230	continue;
3231	dest_se_tpg = tmp_lun->lun_tpg;
3232	dest_tf_ops = dest_se_tpg->se_tpg_tfo;
3233	if (!dest_tf_ops)
3234	continue;
3235
3236	atomic_inc_mb(v: &dest_se_tpg->tpg_pr_ref_count);
3237	spin_unlock(lock: &dev->se_port_lock);
3238
3239	if (core_scsi3_tpg_depend_item(tpg: dest_se_tpg)) {
3240	pr_err("core_scsi3_tpg_depend_item() failed"
3241	" for dest_se_tpg\n");
3242	atomic_dec_mb(v: &dest_se_tpg->tpg_pr_ref_count);
3243	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3244	goto out_put_pr_reg;
3245	}
3246
3247	spin_lock(lock: &dev->se_port_lock);
3248	break;
3249	}
3250	spin_unlock(lock: &dev->se_port_lock);
3251
3252	if (!dest_se_tpg || !dest_tf_ops) {
3253	pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3254	" fabric ops from Relative Target Port Identifier:"
3255	" %hu\n", rtpi);
3256	ret = TCM_INVALID_PARAMETER_LIST;
3257	goto out_put_pr_reg;
3258	}
3259
3260	buf = transport_kmap_data_sg(cmd);
3261	if (!buf) {
3262	ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3263	goto out_put_pr_reg;
3264	}
3265	proto_ident = (buf[24] & 0x0f);
3266
3267	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Extracted Protocol Identifier:"
3268	" 0x%02x\n", proto_ident);
3269
3270	if (proto_ident != dest_se_tpg->proto_id) {
3271	pr_err("SPC-3 PR REGISTER_AND_MOVE: Received"
3272	" proto_ident: 0x%02x does not match ident: 0x%02x"
3273	" from fabric: %s\n", proto_ident,
3274	dest_se_tpg->proto_id,
3275	dest_tf_ops->fabric_name);
3276	ret = TCM_INVALID_PARAMETER_LIST;
3277	goto out;
3278	}
3279	initiator_str = target_parse_pr_out_transport_id(tpg: dest_se_tpg,
3280	buf: &buf[24], out_tid_len: &tmp_tid_len, port_nexus_ptr: &iport_ptr);
3281	if (!initiator_str) {
3282	pr_err("SPC-3 PR REGISTER_AND_MOVE: Unable to locate"
3283	" initiator_str from Transport ID\n");
3284	ret = TCM_INVALID_PARAMETER_LIST;
3285	goto out;
3286	}
3287
3288	transport_kunmap_data_sg(cmd);
3289	buf = NULL;
3290
3291	pr_debug("SPC-3 PR [%s] Extracted initiator %s identifier: %s"
3292	" %s\n", dest_tf_ops->fabric_name, (iport_ptr != NULL) ?
3293	"port" : "device", initiator_str, (iport_ptr != NULL) ?
3294	iport_ptr : "");
3295	/*
3296	* If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3297	* action specifies a TransportID that is the same as the initiator port
3298	* of the I_T nexus for the command received, then the command shall
3299	* be terminated with CHECK CONDITION status, with the sense key set to
3300	* ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD
3301	* IN PARAMETER LIST.
3302	*/
3303	pr_reg_nacl = pr_reg->pr_reg_nacl;
3304	matching_iname = (!strcmp(initiator_str,
3305	pr_reg_nacl->initiatorname)) ? 1 : 0;
3306	if (!matching_iname)
3307	goto after_iport_check;
3308
3309	if (!iport_ptr || !pr_reg->isid_present_at_reg) {
3310	pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s"
3311	" matches: %s on received I_T Nexus\n", initiator_str,
3312	pr_reg_nacl->initiatorname);
3313	ret = TCM_INVALID_PARAMETER_LIST;
3314	goto out;
3315	}
3316	if (!strcmp(iport_ptr, pr_reg->pr_reg_isid)) {
3317	pr_err("SPC-3 PR REGISTER_AND_MOVE: TransportID: %s %s"
3318	" matches: %s %s on received I_T Nexus\n",
3319	initiator_str, iport_ptr, pr_reg_nacl->initiatorname,
3320	pr_reg->pr_reg_isid);
3321	ret = TCM_INVALID_PARAMETER_LIST;
3322	goto out;
3323	}
3324	after_iport_check:
3325	/*
3326	* Locate the destination struct se_node_acl from the received Transport ID
3327	*/
3328	mutex_lock(&dest_se_tpg->acl_node_mutex);
3329	dest_node_acl = __core_tpg_get_initiator_node_acl(tpg: dest_se_tpg,
3330	initiator_str);
3331	if (dest_node_acl)
3332	atomic_inc_mb(v: &dest_node_acl->acl_pr_ref_count);
3333	mutex_unlock(lock: &dest_se_tpg->acl_node_mutex);
3334
3335	if (!dest_node_acl) {
3336	pr_err("Unable to locate %s dest_node_acl for"
3337	" TransportID%s\n", dest_tf_ops->fabric_name,
3338	initiator_str);
3339	ret = TCM_INVALID_PARAMETER_LIST;
3340	goto out;
3341	}
3342
3343	if (core_scsi3_nodeacl_depend_item(nacl: dest_node_acl)) {
3344	pr_err("core_scsi3_nodeacl_depend_item() for"
3345	" dest_node_acl\n");
3346	atomic_dec_mb(v: &dest_node_acl->acl_pr_ref_count);
3347	dest_node_acl = NULL;
3348	ret = TCM_INVALID_PARAMETER_LIST;
3349	goto out;
3350	}
3351
3352	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Found %s dest_node_acl:"
3353	" %s from TransportID\n", dest_tf_ops->fabric_name,
3354	dest_node_acl->initiatorname);
3355
3356	/*
3357	* Locate the struct se_dev_entry pointer for the matching RELATIVE TARGET
3358	* PORT IDENTIFIER.
3359	*/
3360	dest_se_deve = core_get_se_deve_from_rtpi(dest_node_acl, rtpi);
3361	if (!dest_se_deve) {
3362	pr_err("Unable to locate %s dest_se_deve from RTPI:"
3363	" %hu\n", dest_tf_ops->fabric_name, rtpi);
3364	ret = TCM_INVALID_PARAMETER_LIST;
3365	goto out;
3366	}
3367
3368	if (core_scsi3_lunacl_depend_item(se_deve: dest_se_deve)) {
3369	pr_err("core_scsi3_lunacl_depend_item() failed\n");
3370	kref_put(kref: &dest_se_deve->pr_kref, release: target_pr_kref_release);
3371	dest_se_deve = NULL;
3372	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3373	goto out;
3374	}
3375
3376	pr_debug("SPC-3 PR REGISTER_AND_MOVE: Located %s node %s LUN"
3377	" ACL for dest_se_deve->mapped_lun: %llu\n",
3378	dest_tf_ops->fabric_name, dest_node_acl->initiatorname,
3379	dest_se_deve->mapped_lun);
3380
3381	/*
3382	* A persistent reservation needs to already existing in order to
3383	* successfully complete the REGISTER_AND_MOVE service action..
3384	*/
3385	spin_lock(lock: &dev->dev_reservation_lock);
3386	pr_res_holder = dev->dev_pr_res_holder;
3387	if (!pr_res_holder) {
3388	pr_warn("SPC-3 PR REGISTER_AND_MOVE: No reservation"
3389	" currently held\n");
3390	spin_unlock(lock: &dev->dev_reservation_lock);
3391	ret = TCM_INVALID_CDB_FIELD;
3392	goto out;
3393	}
3394	/*
3395	* The received on I_T Nexus must be the reservation holder.
3396	*
3397	* From spc4r17 section 5.7.8 Table 50 --
3398	* Register behaviors for a REGISTER AND MOVE service action
3399	*/
3400	if (!is_reservation_holder(pr_res_holder, pr_reg)) {
3401	pr_warn("SPC-3 PR REGISTER_AND_MOVE: Calling I_T"
3402	" Nexus is not reservation holder\n");
3403	spin_unlock(lock: &dev->dev_reservation_lock);
3404	ret = TCM_RESERVATION_CONFLICT;
3405	goto out;
3406	}
3407	/*
3408	* From spc4r17 section 5.7.8: registering and moving reservation
3409	*
3410	* If a PERSISTENT RESERVE OUT command with a REGISTER AND MOVE service
3411	* action is received and the established persistent reservation is a
3412	* Write Exclusive - All Registrants type or Exclusive Access -
3413	* All Registrants type reservation, then the command shall be completed
3414	* with RESERVATION CONFLICT status.
3415	*/
3416	if ((pr_res_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3417	(pr_res_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG)) {
3418	pr_warn("SPC-3 PR REGISTER_AND_MOVE: Unable to move"
3419	" reservation for type: %s\n",
3420	core_scsi3_pr_dump_type(pr_res_holder->pr_res_type));
3421	spin_unlock(lock: &dev->dev_reservation_lock);
3422	ret = TCM_RESERVATION_CONFLICT;
3423	goto out;
3424	}
3425	pr_res_nacl = pr_res_holder->pr_reg_nacl;
3426	/*
3427	* b) Ignore the contents of the (received) SCOPE and TYPE fields;
3428	*/
3429	type = pr_res_holder->pr_res_type;
3430	scope = pr_res_holder->pr_res_type;
3431	/*
3432	* c) Associate the reservation key specified in the SERVICE ACTION
3433	* RESERVATION KEY field with the I_T nexus specified as the
3434	* destination of the register and move, where:
3435	* A) The I_T nexus is specified by the TransportID and the
3436	* RELATIVE TARGET PORT IDENTIFIER field (see 6.14.4); and
3437	* B) Regardless of the TransportID format used, the association for
3438	* the initiator port is based on either the initiator port name
3439	* (see 3.1.71) on SCSI transport protocols where port names are
3440	* required or the initiator port identifier (see 3.1.70) on SCSI
3441	* transport protocols where port names are not required;
3442	* d) Register the reservation key specified in the SERVICE ACTION
3443	* RESERVATION KEY field;
3444	*
3445	* Also, It is not an error for a REGISTER AND MOVE service action to
3446	* register an I_T nexus that is already registered with the same
3447	* reservation key or a different reservation key.
3448	*/
3449	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, nacl: dest_node_acl,
3450	isid: iport_ptr);
3451	if (!dest_pr_reg) {
3452	struct se_lun *dest_lun = dest_se_deve->se_lun;
3453
3454	spin_unlock(lock: &dev->dev_reservation_lock);
3455	if (core_scsi3_alloc_registration(dev: cmd->se_dev, nacl: dest_node_acl,
3456	lun: dest_lun, deve: dest_se_deve, mapped_lun: dest_se_deve->mapped_lun,
3457	isid: iport_ptr, sa_res_key, all_tg_pt: 0, aptpl, register_type: 2, register_move: 1)) {
3458	ret = TCM_INSUFFICIENT_REGISTRATION_RESOURCES;
3459	goto out;
3460	}
3461	spin_lock(lock: &dev->dev_reservation_lock);
3462	dest_pr_reg = __core_scsi3_locate_pr_reg(dev, nacl: dest_node_acl,
3463	isid: iport_ptr);
3464	new_reg = 1;
3465	} else {
3466	/*
3467	* e) Retain the reservation key specified in the SERVICE ACTION
3468	* RESERVATION KEY field and associated information;
3469	*/
3470	dest_pr_reg->pr_res_key = sa_res_key;
3471	}
3472	/*
3473	* f) Release the persistent reservation for the persistent reservation
3474	* holder (i.e., the I_T nexus on which the
3475	*/
3476	__core_scsi3_complete_pro_release(dev, se_nacl: pr_res_nacl,
3477	pr_reg: dev->dev_pr_res_holder, explicit: 0, unreg: 0);
3478	/*
3479	* g) Move the persistent reservation to the specified I_T nexus using
3480	* the same scope and type as the persistent reservation released in
3481	* item f); and
3482	*/
3483	dev->dev_pr_res_holder = dest_pr_reg;
3484	dest_pr_reg->pr_res_holder = 1;
3485	dest_pr_reg->pr_res_type = type;
3486	pr_reg->pr_res_scope = scope;
3487	core_pr_dump_initiator_port(pr_reg, buf: i_buf, PR_REG_ISID_ID_LEN);
3488	/*
3489	* Increment PRGeneration for existing registrations..
3490	*/
3491	if (!new_reg)
3492	dest_pr_reg->pr_res_generation = pr_tmpl->pr_generation++;
3493	spin_unlock(lock: &dev->dev_reservation_lock);
3494
3495	pr_debug("SPC-3 PR [%s] Service Action: REGISTER_AND_MOVE"
3496	" created new reservation holder TYPE: %s on object RTPI:"
3497	" %hu PRGeneration: 0x%08x\n", dest_tf_ops->fabric_name,
3498	core_scsi3_pr_dump_type(type), rtpi,
3499	dest_pr_reg->pr_res_generation);
3500	pr_debug("SPC-3 PR Successfully moved reservation from"
3501	" %s Fabric Node: %s%s -> %s Fabric Node: %s %s\n",
3502	tf_ops->fabric_name, pr_reg_nacl->initiatorname,
3503	i_buf, dest_tf_ops->fabric_name,
3504	dest_node_acl->initiatorname, (iport_ptr != NULL) ?
3505	iport_ptr : "");
3506	/*
3507	* It is now safe to release configfs group dependencies for destination
3508	* of Transport ID Initiator Device/Port Identifier
3509	*/
3510	core_scsi3_lunacl_undepend_item(se_deve: dest_se_deve);
3511	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
3512	core_scsi3_tpg_undepend_item(tpg: dest_se_tpg);
3513	/*
3514	* h) If the UNREG bit is set to one, unregister (see 5.7.11.3) the I_T
3515	* nexus on which PERSISTENT RESERVE OUT command was received.
3516	*/
3517	if (unreg) {
3518	spin_lock(lock: &pr_tmpl->registration_lock);
3519	__core_scsi3_free_registration(dev, pr_reg, NULL, dec_holders: 1);
3520	spin_unlock(lock: &pr_tmpl->registration_lock);
3521	} else
3522	core_scsi3_put_pr_reg(pr_reg);
3523
3524	core_scsi3_update_and_write_aptpl(dev: cmd->se_dev, aptpl);
3525
3526	core_scsi3_put_pr_reg(pr_reg: dest_pr_reg);
3527	return 0;
3528	out:
3529	if (buf)
3530	transport_kunmap_data_sg(cmd);
3531	if (dest_se_deve)
3532	core_scsi3_lunacl_undepend_item(se_deve: dest_se_deve);
3533	if (dest_node_acl)
3534	core_scsi3_nodeacl_undepend_item(nacl: dest_node_acl);
3535	core_scsi3_tpg_undepend_item(tpg: dest_se_tpg);
3536
3537	out_put_pr_reg:
3538	core_scsi3_put_pr_reg(pr_reg);
3539	return ret;
3540	}
3541
3542	static sense_reason_t
3543	target_try_pr_out_pt(struct se_cmd *cmd, u8 sa, u64 res_key, u64 sa_res_key,
3544	u8 type, bool aptpl, bool all_tg_pt, bool spec_i_pt)
3545	{
3546	struct exec_cmd_ops *ops = cmd->protocol_data;
3547
3548	if (!cmd->se_sess || !cmd->se_lun) {
3549	pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n");
3550	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3551	}
3552
3553	if (!ops->execute_pr_out) {
3554	pr_err("SPC-3 PR: Device has been configured for PR passthrough but it's not supported by the backend.\n");
3555	return TCM_UNSUPPORTED_SCSI_OPCODE;
3556	}
3557
3558	switch (sa) {
3559	case PRO_REGISTER_AND_MOVE:
3560	case PRO_REPLACE_LOST_RESERVATION:
3561	pr_err("SPC-3 PR: PRO_REGISTER_AND_MOVE and PRO_REPLACE_LOST_RESERVATION are not supported by PR passthrough.\n");
3562	return TCM_UNSUPPORTED_SCSI_OPCODE;
3563	}
3564
3565	if (spec_i_pt || all_tg_pt) {
3566	pr_err("SPC-3 PR: SPEC_I_PT and ALL_TG_PT are not supported by PR passthrough.\n");
3567	return TCM_UNSUPPORTED_SCSI_OPCODE;
3568	}
3569
3570	return ops->execute_pr_out(cmd, sa, res_key, sa_res_key, type, aptpl);
3571	}
3572
3573	/*
3574	* See spc4r17 section 6.14 Table 170
3575	*/
3576	sense_reason_t
3577	target_scsi3_emulate_pr_out(struct se_cmd *cmd)
3578	{
3579	struct se_device *dev = cmd->se_dev;
3580	unsigned char *cdb = &cmd->t_task_cdb[0];
3581	unsigned char *buf;
3582	u64 res_key, sa_res_key;
3583	int sa, scope, type, aptpl;
3584	int spec_i_pt = 0, all_tg_pt = 0, unreg = 0;
3585	sense_reason_t ret;
3586
3587	/*
3588	* Following spc2r20 5.5.1 Reservations overview:
3589	*
3590	* If a logical unit has been reserved by any RESERVE command and is
3591	* still reserved by any initiator, all PERSISTENT RESERVE IN and all
3592	* PERSISTENT RESERVE OUT commands shall conflict regardless of
3593	* initiator or service action and shall terminate with a RESERVATION
3594	* CONFLICT status.
3595	*/
3596	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
3597	pr_err("Received PERSISTENT_RESERVE CDB while legacy"
3598	" SPC-2 reservation is held, returning"
3599	" RESERVATION_CONFLICT\n");
3600	return TCM_RESERVATION_CONFLICT;
3601	}
3602
3603	/*
3604	* FIXME: A NULL struct se_session pointer means an this is not coming from
3605	* a $FABRIC_MOD's nexus, but from internal passthrough ops.
3606	*/
3607	if (!cmd->se_sess)
3608	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3609
3610	if (cmd->data_length < 24) {
3611	pr_warn("SPC-PR: Received PR OUT parameter list"
3612	" length too small: %u\n", cmd->data_length);
3613	return TCM_PARAMETER_LIST_LENGTH_ERROR;
3614	}
3615
3616	/*
3617	* From the PERSISTENT_RESERVE_OUT command descriptor block (CDB)
3618	*/
3619	sa = (cdb[1] & 0x1f);
3620	scope = (cdb[2] & 0xf0);
3621	type = (cdb[2] & 0x0f);
3622
3623	buf = transport_kmap_data_sg(cmd);
3624	if (!buf)
3625	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3626
3627	/*
3628	* From PERSISTENT_RESERVE_OUT parameter list (payload)
3629	*/
3630	res_key = get_unaligned_be64(p: &buf[0]);
3631	sa_res_key = get_unaligned_be64(p: &buf[8]);
3632	/*
3633	* REGISTER_AND_MOVE uses a different SA parameter list containing
3634	* SCSI TransportIDs.
3635	*/
3636	if (sa != PRO_REGISTER_AND_MOVE) {
3637	spec_i_pt = (buf[20] & 0x08);
3638	all_tg_pt = (buf[20] & 0x04);
3639	aptpl = (buf[20] & 0x01);
3640	} else {
3641	aptpl = (buf[17] & 0x01);
3642	unreg = (buf[17] & 0x02);
3643	}
3644	/*
3645	* If the backend device has been configured to force APTPL metadata
3646	* write-out, go ahead and propigate aptpl=1 down now.
3647	*/
3648	if (dev->dev_attrib.force_pr_aptpl)
3649	aptpl = 1;
3650
3651	transport_kunmap_data_sg(cmd);
3652	buf = NULL;
3653
3654	/*
3655	* SPEC_I_PT=1 is only valid for Service action: REGISTER
3656	*/
3657	if (spec_i_pt && (sa != PRO_REGISTER))
3658	return TCM_INVALID_PARAMETER_LIST;
3659
3660	/*
3661	* From spc4r17 section 6.14:
3662	*
3663	* If the SPEC_I_PT bit is set to zero, the service action is not
3664	* REGISTER AND MOVE, and the parameter list length is not 24, then
3665	* the command shall be terminated with CHECK CONDITION status, with
3666	* the sense key set to ILLEGAL REQUEST, and the additional sense
3667	* code set to PARAMETER LIST LENGTH ERROR.
3668	*/
3669	if (!spec_i_pt && (sa != PRO_REGISTER_AND_MOVE) &&
3670	(cmd->data_length != 24)) {
3671	pr_warn("SPC-PR: Received PR OUT illegal parameter"
3672	" list length: %u\n", cmd->data_length);
3673	return TCM_PARAMETER_LIST_LENGTH_ERROR;
3674	}
3675
3676	if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_PGR) {
3677	ret = target_try_pr_out_pt(cmd, sa, res_key, sa_res_key, type,
3678	aptpl, all_tg_pt, spec_i_pt);
3679	goto done;
3680	}
3681
3682	/*
3683	* (core_scsi3_emulate_pro_* function parameters
3684	* are defined by spc4r17 Table 174:
3685	* PERSISTENT_RESERVE_OUT service actions and valid parameters.
3686	*/
3687	switch (sa) {
3688	case PRO_REGISTER:
3689	ret = core_scsi3_emulate_pro_register(cmd,
3690	res_key, sa_res_key, aptpl, all_tg_pt, spec_i_pt, register_type: REGISTER);
3691	break;
3692	case PRO_RESERVE:
3693	ret = core_scsi3_emulate_pro_reserve(cmd, type, scope, res_key);
3694	break;
3695	case PRO_RELEASE:
3696	ret = core_scsi3_emulate_pro_release(cmd, type, scope, res_key);
3697	break;
3698	case PRO_CLEAR:
3699	ret = core_scsi3_emulate_pro_clear(cmd, res_key);
3700	break;
3701	case PRO_PREEMPT:
3702	ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3703	res_key, sa_res_key, preempt_type: PREEMPT);
3704	break;
3705	case PRO_PREEMPT_AND_ABORT:
3706	ret = core_scsi3_emulate_pro_preempt(cmd, type, scope,
3707	res_key, sa_res_key, preempt_type: PREEMPT_AND_ABORT);
3708	break;
3709	case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
3710	ret = core_scsi3_emulate_pro_register(cmd,
3711	res_key: 0, sa_res_key, aptpl, all_tg_pt, spec_i_pt, register_type: REGISTER_AND_IGNORE_EXISTING_KEY);
3712	break;
3713	case PRO_REGISTER_AND_MOVE:
3714	ret = core_scsi3_emulate_pro_register_and_move(cmd, res_key,
3715	sa_res_key, aptpl, unreg);
3716	break;
3717	default:
3718	pr_err("Unknown PERSISTENT_RESERVE_OUT service"
3719	" action: 0x%02x\n", sa);
3720	return TCM_INVALID_CDB_FIELD;
3721	}
3722
3723	done:
3724	if (!ret)
3725	target_complete_cmd(cmd, SAM_STAT_GOOD);
3726	return ret;
3727	}
3728
3729	/*
3730	* PERSISTENT_RESERVE_IN Service Action READ_KEYS
3731	*
3732	* See spc4r17 section 5.7.6.2 and section 6.13.2, Table 160
3733	*/
3734	static sense_reason_t
3735	core_scsi3_pri_read_keys(struct se_cmd *cmd)
3736	{
3737	struct se_device *dev = cmd->se_dev;
3738	struct t10_pr_registration *pr_reg;
3739	unsigned char *buf;
3740	u32 add_len = 0, off = 8;
3741
3742	if (cmd->data_length < 8) {
3743	pr_err("PRIN SA READ_KEYS SCSI Data Length: %u"
3744	" too small\n", cmd->data_length);
3745	return TCM_INVALID_CDB_FIELD;
3746	}
3747
3748	buf = transport_kmap_data_sg(cmd);
3749	if (!buf)
3750	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3751
3752	put_unaligned_be32(val: dev->t10_pr.pr_generation, p: buf);
3753
3754	spin_lock(lock: &dev->t10_pr.registration_lock);
3755	list_for_each_entry(pr_reg, &dev->t10_pr.registration_list,
3756	pr_reg_list) {
3757	/*
3758	* Check for overflow of 8byte PRI READ_KEYS payload and
3759	* next reservation key list descriptor.
3760	*/
3761	if (off + 8 <= cmd->data_length) {
3762	put_unaligned_be64(val: pr_reg->pr_res_key, p: &buf[off]);
3763	off += 8;
3764	}
3765	/*
3766	* SPC5r17: 6.16.2 READ KEYS service action
3767	* The ADDITIONAL LENGTH field indicates the number of bytes in
3768	* the Reservation key list. The contents of the ADDITIONAL
3769	* LENGTH field are not altered based on the allocation length
3770	*/
3771	add_len += 8;
3772	}
3773	spin_unlock(lock: &dev->t10_pr.registration_lock);
3774
3775	put_unaligned_be32(val: add_len, p: &buf[4]);
3776	target_set_cmd_data_length(cmd, 8 + add_len);
3777
3778	transport_kunmap_data_sg(cmd);
3779
3780	return 0;
3781	}
3782
3783	/*
3784	* PERSISTENT_RESERVE_IN Service Action READ_RESERVATION
3785	*
3786	* See spc4r17 section 5.7.6.3 and section 6.13.3.2 Table 161 and 162
3787	*/
3788	static sense_reason_t
3789	core_scsi3_pri_read_reservation(struct se_cmd *cmd)
3790	{
3791	struct se_device *dev = cmd->se_dev;
3792	struct t10_pr_registration *pr_reg;
3793	unsigned char *buf;
3794	u64 pr_res_key;
3795	u32 add_len = 0;
3796
3797	if (cmd->data_length < 8) {
3798	pr_err("PRIN SA READ_RESERVATIONS SCSI Data Length: %u"
3799	" too small\n", cmd->data_length);
3800	return TCM_INVALID_CDB_FIELD;
3801	}
3802
3803	buf = transport_kmap_data_sg(cmd);
3804	if (!buf)
3805	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3806
3807	put_unaligned_be32(val: dev->t10_pr.pr_generation, p: &buf[0]);
3808
3809	spin_lock(lock: &dev->dev_reservation_lock);
3810	pr_reg = dev->dev_pr_res_holder;
3811	if (pr_reg) {
3812	/*
3813	* Set the Additional Length to 16 when a reservation is held
3814	*/
3815	add_len = 16;
3816	put_unaligned_be32(val: add_len, p: &buf[4]);
3817
3818	if (cmd->data_length < 22)
3819	goto err;
3820
3821	/*
3822	* Set the Reservation key.
3823	*
3824	* From spc4r17, section 5.7.10:
3825	* A persistent reservation holder has its reservation key
3826	* returned in the parameter data from a PERSISTENT
3827	* RESERVE IN command with READ RESERVATION service action as
3828	* follows:
3829	* a) For a persistent reservation of the type Write Exclusive
3830	* - All Registrants or Exclusive Access ­ All Regitrants,
3831	* the reservation key shall be set to zero; or
3832	* b) For all other persistent reservation types, the
3833	* reservation key shall be set to the registered
3834	* reservation key for the I_T nexus that holds the
3835	* persistent reservation.
3836	*/
3837	if ((pr_reg->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG) ||
3838	(pr_reg->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG))
3839	pr_res_key = 0;
3840	else
3841	pr_res_key = pr_reg->pr_res_key;
3842
3843	put_unaligned_be64(val: pr_res_key, p: &buf[8]);
3844	/*
3845	* Set the SCOPE and TYPE
3846	*/
3847	buf[21] = (pr_reg->pr_res_scope & 0xf0) |
3848	(pr_reg->pr_res_type & 0x0f);
3849	}
3850
3851	target_set_cmd_data_length(cmd, 8 + add_len);
3852
3853	err:
3854	spin_unlock(lock: &dev->dev_reservation_lock);
3855	transport_kunmap_data_sg(cmd);
3856
3857	return 0;
3858	}
3859
3860	/*
3861	* PERSISTENT_RESERVE_IN Service Action REPORT_CAPABILITIES
3862	*
3863	* See spc4r17 section 6.13.4 Table 165
3864	*/
3865	static sense_reason_t
3866	core_scsi3_pri_report_capabilities(struct se_cmd *cmd)
3867	{
3868	struct se_device *dev = cmd->se_dev;
3869	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3870	unsigned char *buf;
3871	u16 len = 8; /* Hardcoded to 8. */
3872
3873	if (cmd->data_length < 6) {
3874	pr_err("PRIN SA REPORT_CAPABILITIES SCSI Data Length:"
3875	" %u too small\n", cmd->data_length);
3876	return TCM_INVALID_CDB_FIELD;
3877	}
3878
3879	buf = transport_kmap_data_sg(cmd);
3880	if (!buf)
3881	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3882
3883	put_unaligned_be16(val: len, p: &buf[0]);
3884	buf[2] |= 0x10; /* CRH: Compatible Reservation Hanlding bit. */
3885	buf[2] |= 0x08; /* SIP_C: Specify Initiator Ports Capable bit */
3886	buf[2] |= 0x04; /* ATP_C: All Target Ports Capable bit */
3887	buf[2] |= 0x01; /* PTPL_C: Persistence across Target Power Loss bit */
3888	/*
3889	* We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
3890	* set the TMV: Task Mask Valid bit.
3891	*/
3892	buf[3] |= 0x80;
3893	/*
3894	* Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
3895	*/
3896	buf[3] |= 0x10; /* ALLOW COMMANDs field 001b */
3897	/*
3898	* PTPL_A: Persistence across Target Power Loss Active bit
3899	*/
3900	if (pr_tmpl->pr_aptpl_active)
3901	buf[3] |= 0x01;
3902	/*
3903	* Setup the PERSISTENT RESERVATION TYPE MASK from Table 167
3904	*/
3905	buf[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3906	buf[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
3907	buf[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
3908	buf[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
3909	buf[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
3910	buf[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
3911
3912	target_set_cmd_data_length(cmd, len);
3913
3914	transport_kunmap_data_sg(cmd);
3915
3916	return 0;
3917	}
3918
3919	/*
3920	* PERSISTENT_RESERVE_IN Service Action READ_FULL_STATUS
3921	*
3922	* See spc4r17 section 6.13.5 Table 168 and 169
3923	*/
3924	static sense_reason_t
3925	core_scsi3_pri_read_full_status(struct se_cmd *cmd)
3926	{
3927	struct se_device *dev = cmd->se_dev;
3928	struct se_node_acl *se_nacl;
3929	struct se_portal_group *se_tpg;
3930	struct t10_pr_registration *pr_reg, *pr_reg_tmp;
3931	struct t10_reservation *pr_tmpl = &dev->t10_pr;
3932	unsigned char *buf;
3933	u32 add_desc_len = 0, add_len = 0;
3934	u32 off = 8; /* off into first Full Status descriptor */
3935	int format_code = 0, pr_res_type = 0, pr_res_scope = 0;
3936	int exp_desc_len, desc_len;
3937	bool all_reg = false;
3938
3939	if (cmd->data_length < 8) {
3940	pr_err("PRIN SA READ_FULL_STATUS SCSI Data Length: %u"
3941	" too small\n", cmd->data_length);
3942	return TCM_INVALID_CDB_FIELD;
3943	}
3944
3945	buf = transport_kmap_data_sg(cmd);
3946	if (!buf)
3947	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
3948
3949	put_unaligned_be32(val: dev->t10_pr.pr_generation, p: &buf[0]);
3950
3951	spin_lock(lock: &dev->dev_reservation_lock);
3952	if (dev->dev_pr_res_holder) {
3953	struct t10_pr_registration *pr_holder = dev->dev_pr_res_holder;
3954
3955	if (pr_holder->pr_res_type == PR_TYPE_WRITE_EXCLUSIVE_ALLREG ||
3956	pr_holder->pr_res_type == PR_TYPE_EXCLUSIVE_ACCESS_ALLREG) {
3957	all_reg = true;
3958	pr_res_type = pr_holder->pr_res_type;
3959	pr_res_scope = pr_holder->pr_res_scope;
3960	}
3961	}
3962	spin_unlock(lock: &dev->dev_reservation_lock);
3963
3964	spin_lock(lock: &pr_tmpl->registration_lock);
3965	list_for_each_entry_safe(pr_reg, pr_reg_tmp,
3966	&pr_tmpl->registration_list, pr_reg_list) {
3967
3968	se_nacl = pr_reg->pr_reg_nacl;
3969	se_tpg = pr_reg->pr_reg_nacl->se_tpg;
3970	add_desc_len = 0;
3971
3972	atomic_inc_mb(v: &pr_reg->pr_res_holders);
3973	spin_unlock(lock: &pr_tmpl->registration_lock);
3974	/*
3975	* Determine expected length of $FABRIC_MOD specific
3976	* TransportID full status descriptor..
3977	*/
3978	exp_desc_len = target_get_pr_transport_id_len(nacl: se_nacl, pr_reg,
3979	format_code: &format_code);
3980	if (exp_desc_len < 0 ||
3981	exp_desc_len + add_len > cmd->data_length) {
3982	pr_warn("SPC-3 PRIN READ_FULL_STATUS ran"
3983	" out of buffer: %d\n", cmd->data_length);
3984	spin_lock(lock: &pr_tmpl->registration_lock);
3985	atomic_dec_mb(v: &pr_reg->pr_res_holders);
3986	break;
3987	}
3988	/*
3989	* Set RESERVATION KEY
3990	*/
3991	put_unaligned_be64(val: pr_reg->pr_res_key, p: &buf[off]);
3992	off += 8;
3993	off += 4; /* Skip Over Reserved area */
3994
3995	/*
3996	* Set ALL_TG_PT bit if PROUT SA REGISTER had this set.
3997	*/
3998	if (pr_reg->pr_reg_all_tg_pt)
3999	buf[off] = 0x02;
4000	/*
4001	* The struct se_lun pointer will be present for the
4002	* reservation holder for PR_HOLDER bit.
4003	*
4004	* Also, if this registration is the reservation
4005	* holder or there is an All Registrants reservation
4006	* active, fill in SCOPE and TYPE in the next byte.
4007	*/
4008	if (pr_reg->pr_res_holder) {
4009	buf[off++] |= 0x01;
4010	buf[off++] = (pr_reg->pr_res_scope & 0xf0) |
4011	(pr_reg->pr_res_type & 0x0f);
4012	} else if (all_reg) {
4013	buf[off++] |= 0x01;
4014	buf[off++] = (pr_res_scope & 0xf0) |
4015	(pr_res_type & 0x0f);
4016	} else {
4017	off += 2;
4018	}
4019
4020	off += 4; /* Skip over reserved area */
4021	/*
4022	* From spc4r17 6.3.15:
4023	*
4024	* If the ALL_TG_PT bit set to zero, the RELATIVE TARGET PORT
4025	* IDENTIFIER field contains the relative port identifier (see
4026	* 3.1.120) of the target port that is part of the I_T nexus
4027	* described by this full status descriptor. If the ALL_TG_PT
4028	* bit is set to one, the contents of the RELATIVE TARGET PORT
4029	* IDENTIFIER field are not defined by this standard.
4030	*/
4031	if (!pr_reg->pr_reg_all_tg_pt) {
4032	u16 sep_rtpi = pr_reg->tg_pt_sep_rtpi;
4033
4034	put_unaligned_be16(val: sep_rtpi, p: &buf[off]);
4035	off += 2;
4036	} else
4037	off += 2; /* Skip over RELATIVE TARGET PORT IDENTIFIER */
4038
4039	buf[off+4] = se_tpg->proto_id;
4040
4041	/*
4042	* Now, have the $FABRIC_MOD fill in the transport ID.
4043	*/
4044	desc_len = target_get_pr_transport_id(nacl: se_nacl, pr_reg,
4045	format_code: &format_code, buf: &buf[off+4]);
4046
4047	spin_lock(lock: &pr_tmpl->registration_lock);
4048	atomic_dec_mb(v: &pr_reg->pr_res_holders);
4049
4050	if (desc_len < 0)
4051	break;
4052	/*
4053	* Set the ADDITIONAL DESCRIPTOR LENGTH
4054	*/
4055	put_unaligned_be32(val: desc_len, p: &buf[off]);
4056	off += 4;
4057	/*
4058	* Size of full desctipor header minus TransportID
4059	* containing $FABRIC_MOD specific) initiator device/port
4060	* WWN information.
4061	*
4062	* See spc4r17 Section 6.13.5 Table 169
4063	*/
4064	add_desc_len = (24 + desc_len);
4065
4066	off += desc_len;
4067	add_len += add_desc_len;
4068	}
4069	spin_unlock(lock: &pr_tmpl->registration_lock);
4070	/*
4071	* Set ADDITIONAL_LENGTH
4072	*/
4073	put_unaligned_be32(val: add_len, p: &buf[4]);
4074	target_set_cmd_data_length(cmd, 8 + add_len);
4075
4076	transport_kunmap_data_sg(cmd);
4077
4078	return 0;
4079	}
4080
4081	static sense_reason_t target_try_pr_in_pt(struct se_cmd *cmd, u8 sa)
4082	{
4083	struct exec_cmd_ops *ops = cmd->protocol_data;
4084	unsigned char *buf;
4085	sense_reason_t ret;
4086
4087	if (cmd->data_length < 8) {
4088	pr_err("PRIN SA SCSI Data Length: %u too small\n",
4089	cmd->data_length);
4090	return TCM_INVALID_CDB_FIELD;
4091	}
4092
4093	if (!ops->execute_pr_in) {
4094	pr_err("SPC-3 PR: Device has been configured for PR passthrough but it's not supported by the backend.\n");
4095	return TCM_UNSUPPORTED_SCSI_OPCODE;
4096	}
4097
4098	if (sa == PRI_READ_FULL_STATUS) {
4099	pr_err("SPC-3 PR: PRI_READ_FULL_STATUS is not supported by PR passthrough.\n");
4100	return TCM_UNSUPPORTED_SCSI_OPCODE;
4101	}
4102
4103	buf = transport_kmap_data_sg(cmd);
4104	if (!buf)
4105	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
4106
4107	ret = ops->execute_pr_in(cmd, sa, buf);
4108
4109	transport_kunmap_data_sg(cmd);
4110	return ret;
4111	}
4112
4113	sense_reason_t
4114	target_scsi3_emulate_pr_in(struct se_cmd *cmd)
4115	{
4116	u8 sa = cmd->t_task_cdb[1] & 0x1f;
4117	sense_reason_t ret;
4118
4119	/*
4120	* Following spc2r20 5.5.1 Reservations overview:
4121	*
4122	* If a logical unit has been reserved by any RESERVE command and is
4123	* still reserved by any initiator, all PERSISTENT RESERVE IN and all
4124	* PERSISTENT RESERVE OUT commands shall conflict regardless of
4125	* initiator or service action and shall terminate with a RESERVATION
4126	* CONFLICT status.
4127	*/
4128	if (cmd->se_dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS) {
4129	pr_err("Received PERSISTENT_RESERVE CDB while legacy"
4130	" SPC-2 reservation is held, returning"
4131	" RESERVATION_CONFLICT\n");
4132	return TCM_RESERVATION_CONFLICT;
4133	}
4134
4135	if (cmd->se_dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_PGR) {
4136	ret = target_try_pr_in_pt(cmd, sa);
4137	goto done;
4138	}
4139
4140	switch (sa) {
4141	case PRI_READ_KEYS:
4142	ret = core_scsi3_pri_read_keys(cmd);
4143	break;
4144	case PRI_READ_RESERVATION:
4145	ret = core_scsi3_pri_read_reservation(cmd);
4146	break;
4147	case PRI_REPORT_CAPABILITIES:
4148	ret = core_scsi3_pri_report_capabilities(cmd);
4149	break;
4150	case PRI_READ_FULL_STATUS:
4151	ret = core_scsi3_pri_read_full_status(cmd);
4152	break;
4153	default:
4154	pr_err("Unknown PERSISTENT_RESERVE_IN service"
4155	" action: 0x%02x\n", cmd->t_task_cdb[1] & 0x1f);
4156	return TCM_INVALID_CDB_FIELD;
4157	}
4158
4159	done:
4160	if (!ret)
4161	target_complete_cmd(cmd, SAM_STAT_GOOD);
4162	return ret;
4163	}
4164
4165	sense_reason_t
4166	target_check_reservation(struct se_cmd *cmd)
4167	{
4168	struct se_device *dev = cmd->se_dev;
4169	sense_reason_t ret;
4170
4171	if (!cmd->se_sess)
4172	return 0;
4173	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
4174	return 0;
4175	if (!dev->dev_attrib.emulate_pr)
4176	return 0;
4177	if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_PGR)
4178	return 0;
4179
4180	spin_lock(lock: &dev->dev_reservation_lock);
4181	if (dev->dev_reservation_flags & DRF_SPC2_RESERVATIONS)
4182	ret = target_scsi2_reservation_check(cmd);
4183	else
4184	ret = target_scsi3_pr_reservation_check(cmd);
4185	spin_unlock(lock: &dev->dev_reservation_lock);
4186
4187	return ret;
4188	}
4189