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