1 /*******************************************************************************
2  * Filename:  target_core_alua.c
3  *
4  * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
5  *
6  * (c) Copyright 2009-2013 Datera, Inc.
7  *
8  * Nicholas A. Bellinger <nab@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  ******************************************************************************/
25 
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 #include <linux/configfs.h>
29 #include <linux/export.h>
30 #include <linux/file.h>
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_cmnd.h>
33 #include <asm/unaligned.h>
34 
35 #include <target/target_core_base.h>
36 #include <target/target_core_backend.h>
37 #include <target/target_core_fabric.h>
38 #include <target/target_core_configfs.h>
39 
40 #include "target_core_internal.h"
41 #include "target_core_alua.h"
42 #include "target_core_ua.h"
43 
44 static sense_reason_t core_alua_check_transition(int state, int valid,
45 						 int *primary);
46 static int core_alua_set_tg_pt_secondary_state(
47 		struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
48 		struct se_port *port, int explicit, int offline);
49 
50 static char *core_alua_dump_state(int state);
51 
52 static u16 alua_lu_gps_counter;
53 static u32 alua_lu_gps_count;
54 
55 static DEFINE_SPINLOCK(lu_gps_lock);
56 static LIST_HEAD(lu_gps_list);
57 
58 struct t10_alua_lu_gp *default_lu_gp;
59 
60 /*
61  * REPORT REFERRALS
62  *
63  * See sbc3r35 section 5.23
64  */
65 sense_reason_t
66 target_emulate_report_referrals(struct se_cmd *cmd)
67 {
68 	struct se_device *dev = cmd->se_dev;
69 	struct t10_alua_lba_map *map;
70 	struct t10_alua_lba_map_member *map_mem;
71 	unsigned char *buf;
72 	u32 rd_len = 0, off;
73 
74 	if (cmd->data_length < 4) {
75 		pr_warn("REPORT REFERRALS allocation length %u too"
76 			" small\n", cmd->data_length);
77 		return TCM_INVALID_CDB_FIELD;
78 	}
79 
80 	buf = transport_kmap_data_sg(cmd);
81 	if (!buf)
82 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
83 
84 	off = 4;
85 	spin_lock(&dev->t10_alua.lba_map_lock);
86 	if (list_empty(&dev->t10_alua.lba_map_list)) {
87 		spin_unlock(&dev->t10_alua.lba_map_lock);
88 		transport_kunmap_data_sg(cmd);
89 
90 		return TCM_UNSUPPORTED_SCSI_OPCODE;
91 	}
92 
93 	list_for_each_entry(map, &dev->t10_alua.lba_map_list,
94 			    lba_map_list) {
95 		int desc_num = off + 3;
96 		int pg_num;
97 
98 		off += 4;
99 		if (cmd->data_length > off)
100 			put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
101 		off += 8;
102 		if (cmd->data_length > off)
103 			put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
104 		off += 8;
105 		rd_len += 20;
106 		pg_num = 0;
107 		list_for_each_entry(map_mem, &map->lba_map_mem_list,
108 				    lba_map_mem_list) {
109 			int alua_state = map_mem->lba_map_mem_alua_state;
110 			int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
111 
112 			if (cmd->data_length > off)
113 				buf[off] = alua_state & 0x0f;
114 			off += 2;
115 			if (cmd->data_length > off)
116 				buf[off] = (alua_pg_id >> 8) & 0xff;
117 			off++;
118 			if (cmd->data_length > off)
119 				buf[off] = (alua_pg_id & 0xff);
120 			off++;
121 			rd_len += 4;
122 			pg_num++;
123 		}
124 		if (cmd->data_length > desc_num)
125 			buf[desc_num] = pg_num;
126 	}
127 	spin_unlock(&dev->t10_alua.lba_map_lock);
128 
129 	/*
130 	 * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
131 	 */
132 	put_unaligned_be16(rd_len, &buf[2]);
133 
134 	transport_kunmap_data_sg(cmd);
135 
136 	target_complete_cmd(cmd, GOOD);
137 	return 0;
138 }
139 
140 /*
141  * REPORT_TARGET_PORT_GROUPS
142  *
143  * See spc4r17 section 6.27
144  */
145 sense_reason_t
146 target_emulate_report_target_port_groups(struct se_cmd *cmd)
147 {
148 	struct se_device *dev = cmd->se_dev;
149 	struct se_port *port;
150 	struct t10_alua_tg_pt_gp *tg_pt_gp;
151 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
152 	unsigned char *buf;
153 	u32 rd_len = 0, off;
154 	int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
155 
156 	/*
157 	 * Skip over RESERVED area to first Target port group descriptor
158 	 * depending on the PARAMETER DATA FORMAT type..
159 	 */
160 	if (ext_hdr != 0)
161 		off = 8;
162 	else
163 		off = 4;
164 
165 	if (cmd->data_length < off) {
166 		pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
167 			" small for %s header\n", cmd->data_length,
168 			(ext_hdr) ? "extended" : "normal");
169 		return TCM_INVALID_CDB_FIELD;
170 	}
171 	buf = transport_kmap_data_sg(cmd);
172 	if (!buf)
173 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
174 
175 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
176 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
177 			tg_pt_gp_list) {
178 		/*
179 		 * Check if the Target port group and Target port descriptor list
180 		 * based on tg_pt_gp_members count will fit into the response payload.
181 		 * Otherwise, bump rd_len to let the initiator know we have exceeded
182 		 * the allocation length and the response is truncated.
183 		 */
184 		if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
185 		     cmd->data_length) {
186 			rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
187 			continue;
188 		}
189 		/*
190 		 * PREF: Preferred target port bit, determine if this
191 		 * bit should be set for port group.
192 		 */
193 		if (tg_pt_gp->tg_pt_gp_pref)
194 			buf[off] = 0x80;
195 		/*
196 		 * Set the ASYMMETRIC ACCESS State
197 		 */
198 		buf[off++] |= (atomic_read(
199 			&tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
200 		/*
201 		 * Set supported ASYMMETRIC ACCESS State bits
202 		 */
203 		buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
204 		/*
205 		 * TARGET PORT GROUP
206 		 */
207 		buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
208 		buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
209 
210 		off++; /* Skip over Reserved */
211 		/*
212 		 * STATUS CODE
213 		 */
214 		buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
215 		/*
216 		 * Vendor Specific field
217 		 */
218 		buf[off++] = 0x00;
219 		/*
220 		 * TARGET PORT COUNT
221 		 */
222 		buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
223 		rd_len += 8;
224 
225 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
226 		list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
227 				tg_pt_gp_mem_list) {
228 			port = tg_pt_gp_mem->tg_pt;
229 			/*
230 			 * Start Target Port descriptor format
231 			 *
232 			 * See spc4r17 section 6.2.7 Table 247
233 			 */
234 			off += 2; /* Skip over Obsolete */
235 			/*
236 			 * Set RELATIVE TARGET PORT IDENTIFIER
237 			 */
238 			buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
239 			buf[off++] = (port->sep_rtpi & 0xff);
240 			rd_len += 4;
241 		}
242 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
243 	}
244 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
245 	/*
246 	 * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
247 	 */
248 	put_unaligned_be32(rd_len, &buf[0]);
249 
250 	/*
251 	 * Fill in the Extended header parameter data format if requested
252 	 */
253 	if (ext_hdr != 0) {
254 		buf[4] = 0x10;
255 		/*
256 		 * Set the implicit transition time (in seconds) for the application
257 		 * client to use as a base for it's transition timeout value.
258 		 *
259 		 * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
260 		 * this CDB was received upon to determine this value individually
261 		 * for ALUA target port group.
262 		 */
263 		port = cmd->se_lun->lun_sep;
264 		tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
265 		if (tg_pt_gp_mem) {
266 			spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
267 			tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
268 			if (tg_pt_gp)
269 				buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
270 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
271 		}
272 	}
273 	transport_kunmap_data_sg(cmd);
274 
275 	target_complete_cmd(cmd, GOOD);
276 	return 0;
277 }
278 
279 /*
280  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
281  *
282  * See spc4r17 section 6.35
283  */
284 sense_reason_t
285 target_emulate_set_target_port_groups(struct se_cmd *cmd)
286 {
287 	struct se_device *dev = cmd->se_dev;
288 	struct se_port *port, *l_port = cmd->se_lun->lun_sep;
289 	struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
290 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
291 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
292 	unsigned char *buf;
293 	unsigned char *ptr;
294 	sense_reason_t rc = TCM_NO_SENSE;
295 	u32 len = 4; /* Skip over RESERVED area in header */
296 	int alua_access_state, primary = 0, valid_states;
297 	u16 tg_pt_id, rtpi;
298 
299 	if (!l_port)
300 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
301 
302 	if (cmd->data_length < 4) {
303 		pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
304 			" small\n", cmd->data_length);
305 		return TCM_INVALID_PARAMETER_LIST;
306 	}
307 
308 	buf = transport_kmap_data_sg(cmd);
309 	if (!buf)
310 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
311 
312 	/*
313 	 * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
314 	 * for the local tg_pt_gp.
315 	 */
316 	l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
317 	if (!l_tg_pt_gp_mem) {
318 		pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
319 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
320 		goto out;
321 	}
322 	spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
323 	l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
324 	if (!l_tg_pt_gp) {
325 		spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
326 		pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
327 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
328 		goto out;
329 	}
330 	spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
331 
332 	if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
333 		pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
334 				" while TPGS_EXPLICIT_ALUA is disabled\n");
335 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
336 		goto out;
337 	}
338 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
339 
340 	ptr = &buf[4]; /* Skip over RESERVED area in header */
341 
342 	while (len < cmd->data_length) {
343 		bool found = false;
344 		alua_access_state = (ptr[0] & 0x0f);
345 		/*
346 		 * Check the received ALUA access state, and determine if
347 		 * the state is a primary or secondary target port asymmetric
348 		 * access state.
349 		 */
350 		rc = core_alua_check_transition(alua_access_state,
351 						valid_states, &primary);
352 		if (rc) {
353 			/*
354 			 * If the SET TARGET PORT GROUPS attempts to establish
355 			 * an invalid combination of target port asymmetric
356 			 * access states or attempts to establish an
357 			 * unsupported target port asymmetric access state,
358 			 * then the command shall be terminated with CHECK
359 			 * CONDITION status, with the sense key set to ILLEGAL
360 			 * REQUEST, and the additional sense code set to INVALID
361 			 * FIELD IN PARAMETER LIST.
362 			 */
363 			goto out;
364 		}
365 
366 		/*
367 		 * If the ASYMMETRIC ACCESS STATE field (see table 267)
368 		 * specifies a primary target port asymmetric access state,
369 		 * then the TARGET PORT GROUP OR TARGET PORT field specifies
370 		 * a primary target port group for which the primary target
371 		 * port asymmetric access state shall be changed. If the
372 		 * ASYMMETRIC ACCESS STATE field specifies a secondary target
373 		 * port asymmetric access state, then the TARGET PORT GROUP OR
374 		 * TARGET PORT field specifies the relative target port
375 		 * identifier (see 3.1.120) of the target port for which the
376 		 * secondary target port asymmetric access state shall be
377 		 * changed.
378 		 */
379 		if (primary) {
380 			tg_pt_id = get_unaligned_be16(ptr + 2);
381 			/*
382 			 * Locate the matching target port group ID from
383 			 * the global tg_pt_gp list
384 			 */
385 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
386 			list_for_each_entry(tg_pt_gp,
387 					&dev->t10_alua.tg_pt_gps_list,
388 					tg_pt_gp_list) {
389 				if (!tg_pt_gp->tg_pt_gp_valid_id)
390 					continue;
391 
392 				if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
393 					continue;
394 
395 				atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
396 				smp_mb__after_atomic_inc();
397 
398 				spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
399 
400 				if (!core_alua_do_port_transition(tg_pt_gp,
401 						dev, l_port, nacl,
402 						alua_access_state, 1))
403 					found = true;
404 
405 				spin_lock(&dev->t10_alua.tg_pt_gps_lock);
406 				atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
407 				smp_mb__after_atomic_dec();
408 				break;
409 			}
410 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
411 		} else {
412 			/*
413 			 * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
414 			 * the Target Port in question for the the incoming
415 			 * SET_TARGET_PORT_GROUPS op.
416 			 */
417 			rtpi = get_unaligned_be16(ptr + 2);
418 			/*
419 			 * Locate the matching relative target port identifier
420 			 * for the struct se_device storage object.
421 			 */
422 			spin_lock(&dev->se_port_lock);
423 			list_for_each_entry(port, &dev->dev_sep_list,
424 							sep_list) {
425 				if (port->sep_rtpi != rtpi)
426 					continue;
427 
428 				tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
429 
430 				spin_unlock(&dev->se_port_lock);
431 
432 				if (!core_alua_set_tg_pt_secondary_state(
433 						tg_pt_gp_mem, port, 1, 1))
434 					found = true;
435 
436 				spin_lock(&dev->se_port_lock);
437 				break;
438 			}
439 			spin_unlock(&dev->se_port_lock);
440 		}
441 
442 		if (!found) {
443 			rc = TCM_INVALID_PARAMETER_LIST;
444 			goto out;
445 		}
446 
447 		ptr += 4;
448 		len += 4;
449 	}
450 
451 out:
452 	transport_kunmap_data_sg(cmd);
453 	if (!rc)
454 		target_complete_cmd(cmd, GOOD);
455 	return rc;
456 }
457 
458 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
459 {
460 	/*
461 	 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
462 	 * The ALUA additional sense code qualifier (ASCQ) is determined
463 	 * by the ALUA primary or secondary access state..
464 	 */
465 	pr_debug("[%s]: ALUA TG Port not available, "
466 		"SenseKey: NOT_READY, ASC/ASCQ: "
467 		"0x04/0x%02x\n",
468 		cmd->se_tfo->get_fabric_name(), alua_ascq);
469 
470 	cmd->scsi_asc = 0x04;
471 	cmd->scsi_ascq = alua_ascq;
472 }
473 
474 static inline void core_alua_state_nonoptimized(
475 	struct se_cmd *cmd,
476 	unsigned char *cdb,
477 	int nonop_delay_msecs)
478 {
479 	/*
480 	 * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
481 	 * later to determine if processing of this cmd needs to be
482 	 * temporarily delayed for the Active/NonOptimized primary access state.
483 	 */
484 	cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
485 	cmd->alua_nonop_delay = nonop_delay_msecs;
486 }
487 
488 static inline int core_alua_state_lba_dependent(
489 	struct se_cmd *cmd,
490 	struct t10_alua_tg_pt_gp *tg_pt_gp)
491 {
492 	struct se_device *dev = cmd->se_dev;
493 	u64 segment_size, segment_mult, sectors, lba;
494 
495 	/* Only need to check for cdb actually containing LBAs */
496 	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
497 		return 0;
498 
499 	spin_lock(&dev->t10_alua.lba_map_lock);
500 	segment_size = dev->t10_alua.lba_map_segment_size;
501 	segment_mult = dev->t10_alua.lba_map_segment_multiplier;
502 	sectors = cmd->data_length / dev->dev_attrib.block_size;
503 
504 	lba = cmd->t_task_lba;
505 	while (lba < cmd->t_task_lba + sectors) {
506 		struct t10_alua_lba_map *cur_map = NULL, *map;
507 		struct t10_alua_lba_map_member *map_mem;
508 
509 		list_for_each_entry(map, &dev->t10_alua.lba_map_list,
510 				    lba_map_list) {
511 			u64 start_lba, last_lba;
512 			u64 first_lba = map->lba_map_first_lba;
513 
514 			if (segment_mult) {
515 				u64 tmp = lba;
516 				start_lba = do_div(tmp, segment_size * segment_mult);
517 
518 				last_lba = first_lba + segment_size - 1;
519 				if (start_lba >= first_lba &&
520 				    start_lba <= last_lba) {
521 					lba += segment_size;
522 					cur_map = map;
523 					break;
524 				}
525 			} else {
526 				last_lba = map->lba_map_last_lba;
527 				if (lba >= first_lba && lba <= last_lba) {
528 					lba = last_lba + 1;
529 					cur_map = map;
530 					break;
531 				}
532 			}
533 		}
534 		if (!cur_map) {
535 			spin_unlock(&dev->t10_alua.lba_map_lock);
536 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
537 			return 1;
538 		}
539 		list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
540 				    lba_map_mem_list) {
541 			if (map_mem->lba_map_mem_alua_pg_id !=
542 			    tg_pt_gp->tg_pt_gp_id)
543 				continue;
544 			switch(map_mem->lba_map_mem_alua_state) {
545 			case ALUA_ACCESS_STATE_STANDBY:
546 				spin_unlock(&dev->t10_alua.lba_map_lock);
547 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
548 				return 1;
549 			case ALUA_ACCESS_STATE_UNAVAILABLE:
550 				spin_unlock(&dev->t10_alua.lba_map_lock);
551 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
552 				return 1;
553 			default:
554 				break;
555 			}
556 		}
557 	}
558 	spin_unlock(&dev->t10_alua.lba_map_lock);
559 	return 0;
560 }
561 
562 static inline int core_alua_state_standby(
563 	struct se_cmd *cmd,
564 	unsigned char *cdb)
565 {
566 	/*
567 	 * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
568 	 * spc4r17 section 5.9.2.4.4
569 	 */
570 	switch (cdb[0]) {
571 	case INQUIRY:
572 	case LOG_SELECT:
573 	case LOG_SENSE:
574 	case MODE_SELECT:
575 	case MODE_SENSE:
576 	case REPORT_LUNS:
577 	case RECEIVE_DIAGNOSTIC:
578 	case SEND_DIAGNOSTIC:
579 		return 0;
580 	case MAINTENANCE_IN:
581 		switch (cdb[1] & 0x1f) {
582 		case MI_REPORT_TARGET_PGS:
583 			return 0;
584 		default:
585 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
586 			return 1;
587 		}
588 	case MAINTENANCE_OUT:
589 		switch (cdb[1]) {
590 		case MO_SET_TARGET_PGS:
591 			return 0;
592 		default:
593 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
594 			return 1;
595 		}
596 	case REQUEST_SENSE:
597 	case PERSISTENT_RESERVE_IN:
598 	case PERSISTENT_RESERVE_OUT:
599 	case READ_BUFFER:
600 	case WRITE_BUFFER:
601 		return 0;
602 	default:
603 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
604 		return 1;
605 	}
606 
607 	return 0;
608 }
609 
610 static inline int core_alua_state_unavailable(
611 	struct se_cmd *cmd,
612 	unsigned char *cdb)
613 {
614 	/*
615 	 * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
616 	 * spc4r17 section 5.9.2.4.5
617 	 */
618 	switch (cdb[0]) {
619 	case INQUIRY:
620 	case REPORT_LUNS:
621 		return 0;
622 	case MAINTENANCE_IN:
623 		switch (cdb[1] & 0x1f) {
624 		case MI_REPORT_TARGET_PGS:
625 			return 0;
626 		default:
627 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
628 			return 1;
629 		}
630 	case MAINTENANCE_OUT:
631 		switch (cdb[1]) {
632 		case MO_SET_TARGET_PGS:
633 			return 0;
634 		default:
635 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
636 			return 1;
637 		}
638 	case REQUEST_SENSE:
639 	case READ_BUFFER:
640 	case WRITE_BUFFER:
641 		return 0;
642 	default:
643 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
644 		return 1;
645 	}
646 
647 	return 0;
648 }
649 
650 static inline int core_alua_state_transition(
651 	struct se_cmd *cmd,
652 	unsigned char *cdb)
653 {
654 	/*
655 	 * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
656 	 * spc4r17 section 5.9.2.5
657 	 */
658 	switch (cdb[0]) {
659 	case INQUIRY:
660 	case REPORT_LUNS:
661 		return 0;
662 	case MAINTENANCE_IN:
663 		switch (cdb[1] & 0x1f) {
664 		case MI_REPORT_TARGET_PGS:
665 			return 0;
666 		default:
667 			set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
668 			return 1;
669 		}
670 	case REQUEST_SENSE:
671 	case READ_BUFFER:
672 	case WRITE_BUFFER:
673 		return 0;
674 	default:
675 		set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
676 		return 1;
677 	}
678 
679 	return 0;
680 }
681 
682 /*
683  * return 1: Is used to signal LUN not accessible, and check condition/not ready
684  * return 0: Used to signal success
685  * return -1: Used to signal failure, and invalid cdb field
686  */
687 sense_reason_t
688 target_alua_state_check(struct se_cmd *cmd)
689 {
690 	struct se_device *dev = cmd->se_dev;
691 	unsigned char *cdb = cmd->t_task_cdb;
692 	struct se_lun *lun = cmd->se_lun;
693 	struct se_port *port = lun->lun_sep;
694 	struct t10_alua_tg_pt_gp *tg_pt_gp;
695 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
696 	int out_alua_state, nonop_delay_msecs;
697 
698 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
699 		return 0;
700 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
701 		return 0;
702 
703 	if (!port)
704 		return 0;
705 	/*
706 	 * First, check for a struct se_port specific secondary ALUA target port
707 	 * access state: OFFLINE
708 	 */
709 	if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
710 		pr_debug("ALUA: Got secondary offline status for local"
711 				" target port\n");
712 		set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
713 		return TCM_CHECK_CONDITION_NOT_READY;
714 	}
715 	 /*
716 	 * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
717 	 * ALUA target port group, to obtain current ALUA access state.
718 	 * Otherwise look for the underlying struct se_device association with
719 	 * a ALUA logical unit group.
720 	 */
721 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
722 	if (!tg_pt_gp_mem)
723 		return 0;
724 
725 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
726 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
727 	out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
728 	nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
729 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
730 	/*
731 	 * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
732 	 * statement so the compiler knows explicitly to check this case first.
733 	 * For the Optimized ALUA access state case, we want to process the
734 	 * incoming fabric cmd ASAP..
735 	 */
736 	if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
737 		return 0;
738 
739 	switch (out_alua_state) {
740 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
741 		core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
742 		break;
743 	case ALUA_ACCESS_STATE_STANDBY:
744 		if (core_alua_state_standby(cmd, cdb))
745 			return TCM_CHECK_CONDITION_NOT_READY;
746 		break;
747 	case ALUA_ACCESS_STATE_UNAVAILABLE:
748 		if (core_alua_state_unavailable(cmd, cdb))
749 			return TCM_CHECK_CONDITION_NOT_READY;
750 		break;
751 	case ALUA_ACCESS_STATE_TRANSITION:
752 		if (core_alua_state_transition(cmd, cdb))
753 			return TCM_CHECK_CONDITION_NOT_READY;
754 		break;
755 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
756 		if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
757 			return TCM_CHECK_CONDITION_NOT_READY;
758 		break;
759 	/*
760 	 * OFFLINE is a secondary ALUA target port group access state, that is
761 	 * handled above with struct se_port->sep_tg_pt_secondary_offline=1
762 	 */
763 	case ALUA_ACCESS_STATE_OFFLINE:
764 	default:
765 		pr_err("Unknown ALUA access state: 0x%02x\n",
766 				out_alua_state);
767 		return TCM_INVALID_CDB_FIELD;
768 	}
769 
770 	return 0;
771 }
772 
773 /*
774  * Check implicit and explicit ALUA state change request.
775  */
776 static sense_reason_t
777 core_alua_check_transition(int state, int valid, int *primary)
778 {
779 	/*
780 	 * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
781 	 * defined as primary target port asymmetric access states.
782 	 */
783 	switch (state) {
784 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
785 		if (!(valid & ALUA_AO_SUP))
786 			goto not_supported;
787 		*primary = 1;
788 		break;
789 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
790 		if (!(valid & ALUA_AN_SUP))
791 			goto not_supported;
792 		*primary = 1;
793 		break;
794 	case ALUA_ACCESS_STATE_STANDBY:
795 		if (!(valid & ALUA_S_SUP))
796 			goto not_supported;
797 		*primary = 1;
798 		break;
799 	case ALUA_ACCESS_STATE_UNAVAILABLE:
800 		if (!(valid & ALUA_U_SUP))
801 			goto not_supported;
802 		*primary = 1;
803 		break;
804 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
805 		if (!(valid & ALUA_LBD_SUP))
806 			goto not_supported;
807 		*primary = 1;
808 		break;
809 	case ALUA_ACCESS_STATE_OFFLINE:
810 		/*
811 		 * OFFLINE state is defined as a secondary target port
812 		 * asymmetric access state.
813 		 */
814 		if (!(valid & ALUA_O_SUP))
815 			goto not_supported;
816 		*primary = 0;
817 		break;
818 	case ALUA_ACCESS_STATE_TRANSITION:
819 		/*
820 		 * Transitioning is set internally, and
821 		 * cannot be selected manually.
822 		 */
823 		goto not_supported;
824 	default:
825 		pr_err("Unknown ALUA access state: 0x%02x\n", state);
826 		return TCM_INVALID_PARAMETER_LIST;
827 	}
828 
829 	return 0;
830 
831 not_supported:
832 	pr_err("ALUA access state %s not supported",
833 	       core_alua_dump_state(state));
834 	return TCM_INVALID_PARAMETER_LIST;
835 }
836 
837 static char *core_alua_dump_state(int state)
838 {
839 	switch (state) {
840 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
841 		return "Active/Optimized";
842 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
843 		return "Active/NonOptimized";
844 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
845 		return "LBA Dependent";
846 	case ALUA_ACCESS_STATE_STANDBY:
847 		return "Standby";
848 	case ALUA_ACCESS_STATE_UNAVAILABLE:
849 		return "Unavailable";
850 	case ALUA_ACCESS_STATE_OFFLINE:
851 		return "Offline";
852 	case ALUA_ACCESS_STATE_TRANSITION:
853 		return "Transitioning";
854 	default:
855 		return "Unknown";
856 	}
857 
858 	return NULL;
859 }
860 
861 char *core_alua_dump_status(int status)
862 {
863 	switch (status) {
864 	case ALUA_STATUS_NONE:
865 		return "None";
866 	case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
867 		return "Altered by Explicit STPG";
868 	case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
869 		return "Altered by Implicit ALUA";
870 	default:
871 		return "Unknown";
872 	}
873 
874 	return NULL;
875 }
876 
877 /*
878  * Used by fabric modules to determine when we need to delay processing
879  * for the Active/NonOptimized paths..
880  */
881 int core_alua_check_nonop_delay(
882 	struct se_cmd *cmd)
883 {
884 	if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
885 		return 0;
886 	if (in_interrupt())
887 		return 0;
888 	/*
889 	 * The ALUA Active/NonOptimized access state delay can be disabled
890 	 * in via configfs with a value of zero
891 	 */
892 	if (!cmd->alua_nonop_delay)
893 		return 0;
894 	/*
895 	 * struct se_cmd->alua_nonop_delay gets set by a target port group
896 	 * defined interval in core_alua_state_nonoptimized()
897 	 */
898 	msleep_interruptible(cmd->alua_nonop_delay);
899 	return 0;
900 }
901 EXPORT_SYMBOL(core_alua_check_nonop_delay);
902 
903 /*
904  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
905  *
906  */
907 static int core_alua_write_tpg_metadata(
908 	const char *path,
909 	unsigned char *md_buf,
910 	u32 md_buf_len)
911 {
912 	struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
913 	int ret;
914 
915 	if (IS_ERR(file)) {
916 		pr_err("filp_open(%s) for ALUA metadata failed\n", path);
917 		return -ENODEV;
918 	}
919 	ret = kernel_write(file, md_buf, md_buf_len, 0);
920 	if (ret < 0)
921 		pr_err("Error writing ALUA metadata file: %s\n", path);
922 	fput(file);
923 	return (ret < 0) ? -EIO : 0;
924 }
925 
926 /*
927  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
928  */
929 static int core_alua_update_tpg_primary_metadata(
930 	struct t10_alua_tg_pt_gp *tg_pt_gp)
931 {
932 	unsigned char *md_buf;
933 	struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
934 	char path[ALUA_METADATA_PATH_LEN];
935 	int len, rc;
936 
937 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
938 	if (!md_buf) {
939 		pr_err("Unable to allocate buf for ALUA metadata\n");
940 		return -ENOMEM;
941 	}
942 
943 	memset(path, 0, ALUA_METADATA_PATH_LEN);
944 
945 	len = snprintf(md_buf, ALUA_MD_BUF_LEN,
946 			"tg_pt_gp_id=%hu\n"
947 			"alua_access_state=0x%02x\n"
948 			"alua_access_status=0x%02x\n",
949 			tg_pt_gp->tg_pt_gp_id,
950 			tg_pt_gp->tg_pt_gp_alua_pending_state,
951 			tg_pt_gp->tg_pt_gp_alua_access_status);
952 
953 	snprintf(path, ALUA_METADATA_PATH_LEN,
954 		"/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
955 		config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
956 
957 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
958 	kfree(md_buf);
959 	return rc;
960 }
961 
962 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
963 {
964 	struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
965 		struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work.work);
966 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
967 	struct se_dev_entry *se_deve;
968 	struct se_lun_acl *lacl;
969 	struct se_port *port;
970 	struct t10_alua_tg_pt_gp_member *mem;
971 	bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
972 			 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
973 
974 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
975 	list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
976 				tg_pt_gp_mem_list) {
977 		port = mem->tg_pt;
978 		/*
979 		 * After an implicit target port asymmetric access state
980 		 * change, a device server shall establish a unit attention
981 		 * condition for the initiator port associated with every I_T
982 		 * nexus with the additional sense code set to ASYMMETRIC
983 		 * ACCESS STATE CHANGED.
984 		 *
985 		 * After an explicit target port asymmetric access state
986 		 * change, a device server shall establish a unit attention
987 		 * condition with the additional sense code set to ASYMMETRIC
988 		 * ACCESS STATE CHANGED for the initiator port associated with
989 		 * every I_T nexus other than the I_T nexus on which the SET
990 		 * TARGET PORT GROUPS command
991 		 */
992 		atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
993 		smp_mb__after_atomic_inc();
994 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
995 
996 		spin_lock_bh(&port->sep_alua_lock);
997 		list_for_each_entry(se_deve, &port->sep_alua_list,
998 					alua_port_list) {
999 			lacl = se_deve->se_lun_acl;
1000 			/*
1001 			 * se_deve->se_lun_acl pointer may be NULL for a
1002 			 * entry created without explicit Node+MappedLUN ACLs
1003 			 */
1004 			if (!lacl)
1005 				continue;
1006 
1007 			if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
1008 			     ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
1009 			   (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1010 			    (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl) &&
1011 			   (tg_pt_gp->tg_pt_gp_alua_port != NULL) &&
1012 			    (tg_pt_gp->tg_pt_gp_alua_port == port))
1013 				continue;
1014 
1015 			core_scsi3_ua_allocate(lacl->se_lun_nacl,
1016 				se_deve->mapped_lun, 0x2A,
1017 				ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1018 		}
1019 		spin_unlock_bh(&port->sep_alua_lock);
1020 
1021 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1022 		atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
1023 		smp_mb__after_atomic_dec();
1024 	}
1025 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1026 	/*
1027 	 * Update the ALUA metadata buf that has been allocated in
1028 	 * core_alua_do_port_transition(), this metadata will be written
1029 	 * to struct file.
1030 	 *
1031 	 * Note that there is the case where we do not want to update the
1032 	 * metadata when the saved metadata is being parsed in userspace
1033 	 * when setting the existing port access state and access status.
1034 	 *
1035 	 * Also note that the failure to write out the ALUA metadata to
1036 	 * struct file does NOT affect the actual ALUA transition.
1037 	 */
1038 	if (tg_pt_gp->tg_pt_gp_write_metadata) {
1039 		mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1040 		core_alua_update_tpg_primary_metadata(tg_pt_gp);
1041 		mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1042 	}
1043 	/*
1044 	 * Set the current primary ALUA access state to the requested new state
1045 	 */
1046 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1047 		   tg_pt_gp->tg_pt_gp_alua_pending_state);
1048 
1049 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1050 		" from primary access state %s to %s\n", (explicit) ? "explicit" :
1051 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1052 		tg_pt_gp->tg_pt_gp_id,
1053 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1054 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1055 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1056 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1057 	smp_mb__after_atomic_dec();
1058 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1059 
1060 	if (tg_pt_gp->tg_pt_gp_transition_complete)
1061 		complete(tg_pt_gp->tg_pt_gp_transition_complete);
1062 }
1063 
1064 static int core_alua_do_transition_tg_pt(
1065 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1066 	int new_state,
1067 	int explicit)
1068 {
1069 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1070 	DECLARE_COMPLETION_ONSTACK(wait);
1071 
1072 	/* Nothing to be done here */
1073 	if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1074 		return 0;
1075 
1076 	if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1077 		return -EAGAIN;
1078 
1079 	/*
1080 	 * Flush any pending transitions
1081 	 */
1082 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs &&
1083 	    atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
1084 	    ALUA_ACCESS_STATE_TRANSITION) {
1085 		/* Just in case */
1086 		tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1087 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1088 		flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1089 		wait_for_completion(&wait);
1090 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1091 		return 0;
1092 	}
1093 
1094 	/*
1095 	 * Save the old primary ALUA access state, and set the current state
1096 	 * to ALUA_ACCESS_STATE_TRANSITION.
1097 	 */
1098 	tg_pt_gp->tg_pt_gp_alua_previous_state =
1099 		atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1100 	tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1101 
1102 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1103 			ALUA_ACCESS_STATE_TRANSITION);
1104 	tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1105 				ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1106 				ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1107 
1108 	/*
1109 	 * Check for the optional ALUA primary state transition delay
1110 	 */
1111 	if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1112 		msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1113 
1114 	/*
1115 	 * Take a reference for workqueue item
1116 	 */
1117 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1118 	atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1119 	smp_mb__after_atomic_inc();
1120 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1121 
1122 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs) {
1123 		unsigned long transition_tmo;
1124 
1125 		transition_tmo = tg_pt_gp->tg_pt_gp_implicit_trans_secs * HZ;
1126 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1127 				   &tg_pt_gp->tg_pt_gp_transition_work,
1128 				   transition_tmo);
1129 	} else {
1130 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1131 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1132 				   &tg_pt_gp->tg_pt_gp_transition_work, 0);
1133 		wait_for_completion(&wait);
1134 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1135 	}
1136 
1137 	return 0;
1138 }
1139 
1140 int core_alua_do_port_transition(
1141 	struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1142 	struct se_device *l_dev,
1143 	struct se_port *l_port,
1144 	struct se_node_acl *l_nacl,
1145 	int new_state,
1146 	int explicit)
1147 {
1148 	struct se_device *dev;
1149 	struct t10_alua_lu_gp *lu_gp;
1150 	struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1151 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1152 	int primary, valid_states, rc = 0;
1153 
1154 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1155 	if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1156 		return -EINVAL;
1157 
1158 	local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1159 	spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1160 	lu_gp = local_lu_gp_mem->lu_gp;
1161 	atomic_inc(&lu_gp->lu_gp_ref_cnt);
1162 	smp_mb__after_atomic_inc();
1163 	spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1164 	/*
1165 	 * For storage objects that are members of the 'default_lu_gp',
1166 	 * we only do transition on the passed *l_tp_pt_gp, and not
1167 	 * on all of the matching target port groups IDs in default_lu_gp.
1168 	 */
1169 	if (!lu_gp->lu_gp_id) {
1170 		/*
1171 		 * core_alua_do_transition_tg_pt() will always return
1172 		 * success.
1173 		 */
1174 		l_tg_pt_gp->tg_pt_gp_alua_port = l_port;
1175 		l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1176 		rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1177 						   new_state, explicit);
1178 		atomic_dec(&lu_gp->lu_gp_ref_cnt);
1179 		smp_mb__after_atomic_dec();
1180 		return rc;
1181 	}
1182 	/*
1183 	 * For all other LU groups aside from 'default_lu_gp', walk all of
1184 	 * the associated storage objects looking for a matching target port
1185 	 * group ID from the local target port group.
1186 	 */
1187 	spin_lock(&lu_gp->lu_gp_lock);
1188 	list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1189 				lu_gp_mem_list) {
1190 
1191 		dev = lu_gp_mem->lu_gp_mem_dev;
1192 		atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
1193 		smp_mb__after_atomic_inc();
1194 		spin_unlock(&lu_gp->lu_gp_lock);
1195 
1196 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1197 		list_for_each_entry(tg_pt_gp,
1198 				&dev->t10_alua.tg_pt_gps_list,
1199 				tg_pt_gp_list) {
1200 
1201 			if (!tg_pt_gp->tg_pt_gp_valid_id)
1202 				continue;
1203 			/*
1204 			 * If the target behavior port asymmetric access state
1205 			 * is changed for any target port group accessible via
1206 			 * a logical unit within a LU group, the target port
1207 			 * behavior group asymmetric access states for the same
1208 			 * target port group accessible via other logical units
1209 			 * in that LU group will also change.
1210 			 */
1211 			if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1212 				continue;
1213 
1214 			if (l_tg_pt_gp == tg_pt_gp) {
1215 				tg_pt_gp->tg_pt_gp_alua_port = l_port;
1216 				tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1217 			} else {
1218 				tg_pt_gp->tg_pt_gp_alua_port = NULL;
1219 				tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1220 			}
1221 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1222 			smp_mb__after_atomic_inc();
1223 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1224 			/*
1225 			 * core_alua_do_transition_tg_pt() will always return
1226 			 * success.
1227 			 */
1228 			rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1229 					new_state, explicit);
1230 
1231 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1232 			atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1233 			smp_mb__after_atomic_dec();
1234 			if (rc)
1235 				break;
1236 		}
1237 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1238 
1239 		spin_lock(&lu_gp->lu_gp_lock);
1240 		atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
1241 		smp_mb__after_atomic_dec();
1242 	}
1243 	spin_unlock(&lu_gp->lu_gp_lock);
1244 
1245 	if (!rc) {
1246 		pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1247 			 " Group IDs: %hu %s transition to primary state: %s\n",
1248 			 config_item_name(&lu_gp->lu_gp_group.cg_item),
1249 			 l_tg_pt_gp->tg_pt_gp_id,
1250 			 (explicit) ? "explicit" : "implicit",
1251 			 core_alua_dump_state(new_state));
1252 	}
1253 
1254 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1255 	smp_mb__after_atomic_dec();
1256 	return rc;
1257 }
1258 
1259 /*
1260  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
1261  */
1262 static int core_alua_update_tpg_secondary_metadata(
1263 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1264 	struct se_port *port)
1265 {
1266 	unsigned char *md_buf;
1267 	struct se_portal_group *se_tpg = port->sep_tpg;
1268 	char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1269 	int len, rc;
1270 
1271 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1272 	if (!md_buf) {
1273 		pr_err("Unable to allocate buf for ALUA metadata\n");
1274 		return -ENOMEM;
1275 	}
1276 
1277 	memset(path, 0, ALUA_METADATA_PATH_LEN);
1278 	memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1279 
1280 	len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1281 			se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1282 
1283 	if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1284 		snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1285 				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1286 
1287 	len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1288 			"alua_tg_pt_status=0x%02x\n",
1289 			atomic_read(&port->sep_tg_pt_secondary_offline),
1290 			port->sep_tg_pt_secondary_stat);
1291 
1292 	snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
1293 			se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1294 			port->sep_lun->unpacked_lun);
1295 
1296 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
1297 	kfree(md_buf);
1298 
1299 	return rc;
1300 }
1301 
1302 static int core_alua_set_tg_pt_secondary_state(
1303 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1304 	struct se_port *port,
1305 	int explicit,
1306 	int offline)
1307 {
1308 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1309 	int trans_delay_msecs;
1310 
1311 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1312 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1313 	if (!tg_pt_gp) {
1314 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1315 		pr_err("Unable to complete secondary state"
1316 				" transition\n");
1317 		return -EINVAL;
1318 	}
1319 	trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1320 	/*
1321 	 * Set the secondary ALUA target port access state to OFFLINE
1322 	 * or release the previously secondary state for struct se_port
1323 	 */
1324 	if (offline)
1325 		atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1326 	else
1327 		atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1328 
1329 	port->sep_tg_pt_secondary_stat = (explicit) ?
1330 			ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1331 			ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1332 
1333 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1334 		" to secondary access state: %s\n", (explicit) ? "explicit" :
1335 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1336 		tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1337 
1338 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1339 	/*
1340 	 * Do the optional transition delay after we set the secondary
1341 	 * ALUA access state.
1342 	 */
1343 	if (trans_delay_msecs != 0)
1344 		msleep_interruptible(trans_delay_msecs);
1345 	/*
1346 	 * See if we need to update the ALUA fabric port metadata for
1347 	 * secondary state and status
1348 	 */
1349 	if (port->sep_tg_pt_secondary_write_md) {
1350 		mutex_lock(&port->sep_tg_pt_md_mutex);
1351 		core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port);
1352 		mutex_unlock(&port->sep_tg_pt_md_mutex);
1353 	}
1354 
1355 	return 0;
1356 }
1357 
1358 struct t10_alua_lba_map *
1359 core_alua_allocate_lba_map(struct list_head *list,
1360 			   u64 first_lba, u64 last_lba)
1361 {
1362 	struct t10_alua_lba_map *lba_map;
1363 
1364 	lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1365 	if (!lba_map) {
1366 		pr_err("Unable to allocate struct t10_alua_lba_map\n");
1367 		return ERR_PTR(-ENOMEM);
1368 	}
1369 	INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1370 	lba_map->lba_map_first_lba = first_lba;
1371 	lba_map->lba_map_last_lba = last_lba;
1372 
1373 	list_add_tail(&lba_map->lba_map_list, list);
1374 	return lba_map;
1375 }
1376 
1377 int
1378 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1379 			       int pg_id, int state)
1380 {
1381 	struct t10_alua_lba_map_member *lba_map_mem;
1382 
1383 	list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1384 			    lba_map_mem_list) {
1385 		if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1386 			pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1387 			return -EINVAL;
1388 		}
1389 	}
1390 
1391 	lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1392 	if (!lba_map_mem) {
1393 		pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1394 		return -ENOMEM;
1395 	}
1396 	lba_map_mem->lba_map_mem_alua_state = state;
1397 	lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1398 
1399 	list_add_tail(&lba_map_mem->lba_map_mem_list,
1400 		      &lba_map->lba_map_mem_list);
1401 	return 0;
1402 }
1403 
1404 void
1405 core_alua_free_lba_map(struct list_head *lba_list)
1406 {
1407 	struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1408 	struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1409 
1410 	list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1411 				 lba_map_list) {
1412 		list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1413 					 &lba_map->lba_map_mem_list,
1414 					 lba_map_mem_list) {
1415 			list_del(&lba_map_mem->lba_map_mem_list);
1416 			kmem_cache_free(t10_alua_lba_map_mem_cache,
1417 					lba_map_mem);
1418 		}
1419 		list_del(&lba_map->lba_map_list);
1420 		kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1421 	}
1422 }
1423 
1424 void
1425 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1426 		      int segment_size, int segment_mult)
1427 {
1428 	struct list_head old_lba_map_list;
1429 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1430 	int activate = 0, supported;
1431 
1432 	INIT_LIST_HEAD(&old_lba_map_list);
1433 	spin_lock(&dev->t10_alua.lba_map_lock);
1434 	dev->t10_alua.lba_map_segment_size = segment_size;
1435 	dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1436 	list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1437 	if (lba_map_list) {
1438 		list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1439 		activate = 1;
1440 	}
1441 	spin_unlock(&dev->t10_alua.lba_map_lock);
1442 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1443 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1444 			    tg_pt_gp_list) {
1445 
1446 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1447 			continue;
1448 		supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1449 		if (activate)
1450 			supported |= ALUA_LBD_SUP;
1451 		else
1452 			supported &= ~ALUA_LBD_SUP;
1453 		tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1454 	}
1455 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1456 	core_alua_free_lba_map(&old_lba_map_list);
1457 }
1458 
1459 struct t10_alua_lu_gp *
1460 core_alua_allocate_lu_gp(const char *name, int def_group)
1461 {
1462 	struct t10_alua_lu_gp *lu_gp;
1463 
1464 	lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1465 	if (!lu_gp) {
1466 		pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1467 		return ERR_PTR(-ENOMEM);
1468 	}
1469 	INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1470 	INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1471 	spin_lock_init(&lu_gp->lu_gp_lock);
1472 	atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1473 
1474 	if (def_group) {
1475 		lu_gp->lu_gp_id = alua_lu_gps_counter++;
1476 		lu_gp->lu_gp_valid_id = 1;
1477 		alua_lu_gps_count++;
1478 	}
1479 
1480 	return lu_gp;
1481 }
1482 
1483 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1484 {
1485 	struct t10_alua_lu_gp *lu_gp_tmp;
1486 	u16 lu_gp_id_tmp;
1487 	/*
1488 	 * The lu_gp->lu_gp_id may only be set once..
1489 	 */
1490 	if (lu_gp->lu_gp_valid_id) {
1491 		pr_warn("ALUA LU Group already has a valid ID,"
1492 			" ignoring request\n");
1493 		return -EINVAL;
1494 	}
1495 
1496 	spin_lock(&lu_gps_lock);
1497 	if (alua_lu_gps_count == 0x0000ffff) {
1498 		pr_err("Maximum ALUA alua_lu_gps_count:"
1499 				" 0x0000ffff reached\n");
1500 		spin_unlock(&lu_gps_lock);
1501 		kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1502 		return -ENOSPC;
1503 	}
1504 again:
1505 	lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1506 				alua_lu_gps_counter++;
1507 
1508 	list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1509 		if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1510 			if (!lu_gp_id)
1511 				goto again;
1512 
1513 			pr_warn("ALUA Logical Unit Group ID: %hu"
1514 				" already exists, ignoring request\n",
1515 				lu_gp_id);
1516 			spin_unlock(&lu_gps_lock);
1517 			return -EINVAL;
1518 		}
1519 	}
1520 
1521 	lu_gp->lu_gp_id = lu_gp_id_tmp;
1522 	lu_gp->lu_gp_valid_id = 1;
1523 	list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1524 	alua_lu_gps_count++;
1525 	spin_unlock(&lu_gps_lock);
1526 
1527 	return 0;
1528 }
1529 
1530 static struct t10_alua_lu_gp_member *
1531 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1532 {
1533 	struct t10_alua_lu_gp_member *lu_gp_mem;
1534 
1535 	lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1536 	if (!lu_gp_mem) {
1537 		pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1538 		return ERR_PTR(-ENOMEM);
1539 	}
1540 	INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1541 	spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1542 	atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1543 
1544 	lu_gp_mem->lu_gp_mem_dev = dev;
1545 	dev->dev_alua_lu_gp_mem = lu_gp_mem;
1546 
1547 	return lu_gp_mem;
1548 }
1549 
1550 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1551 {
1552 	struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1553 	/*
1554 	 * Once we have reached this point, config_item_put() has
1555 	 * already been called from target_core_alua_drop_lu_gp().
1556 	 *
1557 	 * Here, we remove the *lu_gp from the global list so that
1558 	 * no associations can be made while we are releasing
1559 	 * struct t10_alua_lu_gp.
1560 	 */
1561 	spin_lock(&lu_gps_lock);
1562 	list_del(&lu_gp->lu_gp_node);
1563 	alua_lu_gps_count--;
1564 	spin_unlock(&lu_gps_lock);
1565 	/*
1566 	 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1567 	 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1568 	 * released with core_alua_put_lu_gp_from_name()
1569 	 */
1570 	while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1571 		cpu_relax();
1572 	/*
1573 	 * Release reference to struct t10_alua_lu_gp * from all associated
1574 	 * struct se_device.
1575 	 */
1576 	spin_lock(&lu_gp->lu_gp_lock);
1577 	list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1578 				&lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1579 		if (lu_gp_mem->lu_gp_assoc) {
1580 			list_del(&lu_gp_mem->lu_gp_mem_list);
1581 			lu_gp->lu_gp_members--;
1582 			lu_gp_mem->lu_gp_assoc = 0;
1583 		}
1584 		spin_unlock(&lu_gp->lu_gp_lock);
1585 		/*
1586 		 *
1587 		 * lu_gp_mem is associated with a single
1588 		 * struct se_device->dev_alua_lu_gp_mem, and is released when
1589 		 * struct se_device is released via core_alua_free_lu_gp_mem().
1590 		 *
1591 		 * If the passed lu_gp does NOT match the default_lu_gp, assume
1592 		 * we want to re-associate a given lu_gp_mem with default_lu_gp.
1593 		 */
1594 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1595 		if (lu_gp != default_lu_gp)
1596 			__core_alua_attach_lu_gp_mem(lu_gp_mem,
1597 					default_lu_gp);
1598 		else
1599 			lu_gp_mem->lu_gp = NULL;
1600 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1601 
1602 		spin_lock(&lu_gp->lu_gp_lock);
1603 	}
1604 	spin_unlock(&lu_gp->lu_gp_lock);
1605 
1606 	kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1607 }
1608 
1609 void core_alua_free_lu_gp_mem(struct se_device *dev)
1610 {
1611 	struct t10_alua_lu_gp *lu_gp;
1612 	struct t10_alua_lu_gp_member *lu_gp_mem;
1613 
1614 	lu_gp_mem = dev->dev_alua_lu_gp_mem;
1615 	if (!lu_gp_mem)
1616 		return;
1617 
1618 	while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1619 		cpu_relax();
1620 
1621 	spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1622 	lu_gp = lu_gp_mem->lu_gp;
1623 	if (lu_gp) {
1624 		spin_lock(&lu_gp->lu_gp_lock);
1625 		if (lu_gp_mem->lu_gp_assoc) {
1626 			list_del(&lu_gp_mem->lu_gp_mem_list);
1627 			lu_gp->lu_gp_members--;
1628 			lu_gp_mem->lu_gp_assoc = 0;
1629 		}
1630 		spin_unlock(&lu_gp->lu_gp_lock);
1631 		lu_gp_mem->lu_gp = NULL;
1632 	}
1633 	spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1634 
1635 	kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1636 }
1637 
1638 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1639 {
1640 	struct t10_alua_lu_gp *lu_gp;
1641 	struct config_item *ci;
1642 
1643 	spin_lock(&lu_gps_lock);
1644 	list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1645 		if (!lu_gp->lu_gp_valid_id)
1646 			continue;
1647 		ci = &lu_gp->lu_gp_group.cg_item;
1648 		if (!strcmp(config_item_name(ci), name)) {
1649 			atomic_inc(&lu_gp->lu_gp_ref_cnt);
1650 			spin_unlock(&lu_gps_lock);
1651 			return lu_gp;
1652 		}
1653 	}
1654 	spin_unlock(&lu_gps_lock);
1655 
1656 	return NULL;
1657 }
1658 
1659 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1660 {
1661 	spin_lock(&lu_gps_lock);
1662 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1663 	spin_unlock(&lu_gps_lock);
1664 }
1665 
1666 /*
1667  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1668  */
1669 void __core_alua_attach_lu_gp_mem(
1670 	struct t10_alua_lu_gp_member *lu_gp_mem,
1671 	struct t10_alua_lu_gp *lu_gp)
1672 {
1673 	spin_lock(&lu_gp->lu_gp_lock);
1674 	lu_gp_mem->lu_gp = lu_gp;
1675 	lu_gp_mem->lu_gp_assoc = 1;
1676 	list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1677 	lu_gp->lu_gp_members++;
1678 	spin_unlock(&lu_gp->lu_gp_lock);
1679 }
1680 
1681 /*
1682  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1683  */
1684 void __core_alua_drop_lu_gp_mem(
1685 	struct t10_alua_lu_gp_member *lu_gp_mem,
1686 	struct t10_alua_lu_gp *lu_gp)
1687 {
1688 	spin_lock(&lu_gp->lu_gp_lock);
1689 	list_del(&lu_gp_mem->lu_gp_mem_list);
1690 	lu_gp_mem->lu_gp = NULL;
1691 	lu_gp_mem->lu_gp_assoc = 0;
1692 	lu_gp->lu_gp_members--;
1693 	spin_unlock(&lu_gp->lu_gp_lock);
1694 }
1695 
1696 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1697 		const char *name, int def_group)
1698 {
1699 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1700 
1701 	tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1702 	if (!tg_pt_gp) {
1703 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1704 		return NULL;
1705 	}
1706 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1707 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1708 	mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1709 	spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1710 	atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1711 	INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1712 			  core_alua_do_transition_tg_pt_work);
1713 	tg_pt_gp->tg_pt_gp_dev = dev;
1714 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1715 		ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1716 	/*
1717 	 * Enable both explicit and implicit ALUA support by default
1718 	 */
1719 	tg_pt_gp->tg_pt_gp_alua_access_type =
1720 			TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1721 	/*
1722 	 * Set the default Active/NonOptimized Delay in milliseconds
1723 	 */
1724 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1725 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1726 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1727 
1728 	/*
1729 	 * Enable all supported states
1730 	 */
1731 	tg_pt_gp->tg_pt_gp_alua_supported_states =
1732 	    ALUA_T_SUP | ALUA_O_SUP |
1733 	    ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1734 
1735 	if (def_group) {
1736 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1737 		tg_pt_gp->tg_pt_gp_id =
1738 				dev->t10_alua.alua_tg_pt_gps_counter++;
1739 		tg_pt_gp->tg_pt_gp_valid_id = 1;
1740 		dev->t10_alua.alua_tg_pt_gps_count++;
1741 		list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1742 			      &dev->t10_alua.tg_pt_gps_list);
1743 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1744 	}
1745 
1746 	return tg_pt_gp;
1747 }
1748 
1749 int core_alua_set_tg_pt_gp_id(
1750 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1751 	u16 tg_pt_gp_id)
1752 {
1753 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1754 	struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1755 	u16 tg_pt_gp_id_tmp;
1756 
1757 	/*
1758 	 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1759 	 */
1760 	if (tg_pt_gp->tg_pt_gp_valid_id) {
1761 		pr_warn("ALUA TG PT Group already has a valid ID,"
1762 			" ignoring request\n");
1763 		return -EINVAL;
1764 	}
1765 
1766 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1767 	if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1768 		pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1769 			" 0x0000ffff reached\n");
1770 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1771 		kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1772 		return -ENOSPC;
1773 	}
1774 again:
1775 	tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1776 			dev->t10_alua.alua_tg_pt_gps_counter++;
1777 
1778 	list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1779 			tg_pt_gp_list) {
1780 		if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1781 			if (!tg_pt_gp_id)
1782 				goto again;
1783 
1784 			pr_err("ALUA Target Port Group ID: %hu already"
1785 				" exists, ignoring request\n", tg_pt_gp_id);
1786 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1787 			return -EINVAL;
1788 		}
1789 	}
1790 
1791 	tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1792 	tg_pt_gp->tg_pt_gp_valid_id = 1;
1793 	list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1794 			&dev->t10_alua.tg_pt_gps_list);
1795 	dev->t10_alua.alua_tg_pt_gps_count++;
1796 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1797 
1798 	return 0;
1799 }
1800 
1801 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1802 	struct se_port *port)
1803 {
1804 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1805 
1806 	tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1807 				GFP_KERNEL);
1808 	if (!tg_pt_gp_mem) {
1809 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1810 		return ERR_PTR(-ENOMEM);
1811 	}
1812 	INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1813 	spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1814 	atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1815 
1816 	tg_pt_gp_mem->tg_pt = port;
1817 	port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1818 
1819 	return tg_pt_gp_mem;
1820 }
1821 
1822 void core_alua_free_tg_pt_gp(
1823 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1824 {
1825 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1826 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1827 
1828 	/*
1829 	 * Once we have reached this point, config_item_put() has already
1830 	 * been called from target_core_alua_drop_tg_pt_gp().
1831 	 *
1832 	 * Here we remove *tg_pt_gp from the global list so that
1833 	 * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1834 	 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1835 	 */
1836 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1837 	list_del(&tg_pt_gp->tg_pt_gp_list);
1838 	dev->t10_alua.alua_tg_pt_gps_counter--;
1839 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1840 
1841 	flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1842 
1843 	/*
1844 	 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1845 	 * core_alua_get_tg_pt_gp_by_name() in
1846 	 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1847 	 * to be released with core_alua_put_tg_pt_gp_from_name().
1848 	 */
1849 	while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1850 		cpu_relax();
1851 
1852 	/*
1853 	 * Release reference to struct t10_alua_tg_pt_gp from all associated
1854 	 * struct se_port.
1855 	 */
1856 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1857 	list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1858 			&tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1859 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1860 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1861 			tg_pt_gp->tg_pt_gp_members--;
1862 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1863 		}
1864 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1865 		/*
1866 		 * tg_pt_gp_mem is associated with a single
1867 		 * se_port->sep_alua_tg_pt_gp_mem, and is released via
1868 		 * core_alua_free_tg_pt_gp_mem().
1869 		 *
1870 		 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1871 		 * assume we want to re-associate a given tg_pt_gp_mem with
1872 		 * default_tg_pt_gp.
1873 		 */
1874 		spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1875 		if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1876 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1877 					dev->t10_alua.default_tg_pt_gp);
1878 		} else
1879 			tg_pt_gp_mem->tg_pt_gp = NULL;
1880 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1881 
1882 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1883 	}
1884 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1885 
1886 	kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1887 }
1888 
1889 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1890 {
1891 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1892 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1893 
1894 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1895 	if (!tg_pt_gp_mem)
1896 		return;
1897 
1898 	while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1899 		cpu_relax();
1900 
1901 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1902 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1903 	if (tg_pt_gp) {
1904 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1905 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1906 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1907 			tg_pt_gp->tg_pt_gp_members--;
1908 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1909 		}
1910 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1911 		tg_pt_gp_mem->tg_pt_gp = NULL;
1912 	}
1913 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1914 
1915 	kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1916 }
1917 
1918 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1919 		struct se_device *dev, const char *name)
1920 {
1921 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1922 	struct config_item *ci;
1923 
1924 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1925 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1926 			tg_pt_gp_list) {
1927 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1928 			continue;
1929 		ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1930 		if (!strcmp(config_item_name(ci), name)) {
1931 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1932 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1933 			return tg_pt_gp;
1934 		}
1935 	}
1936 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1937 
1938 	return NULL;
1939 }
1940 
1941 static void core_alua_put_tg_pt_gp_from_name(
1942 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1943 {
1944 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1945 
1946 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1947 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1948 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1949 }
1950 
1951 /*
1952  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1953  */
1954 void __core_alua_attach_tg_pt_gp_mem(
1955 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1956 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1957 {
1958 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1959 	tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1960 	tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1961 	list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1962 			&tg_pt_gp->tg_pt_gp_mem_list);
1963 	tg_pt_gp->tg_pt_gp_members++;
1964 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1965 }
1966 
1967 /*
1968  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1969  */
1970 static void __core_alua_drop_tg_pt_gp_mem(
1971 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1972 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1973 {
1974 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1975 	list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1976 	tg_pt_gp_mem->tg_pt_gp = NULL;
1977 	tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1978 	tg_pt_gp->tg_pt_gp_members--;
1979 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1980 }
1981 
1982 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1983 {
1984 	struct config_item *tg_pt_ci;
1985 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1986 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1987 	ssize_t len = 0;
1988 
1989 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1990 	if (!tg_pt_gp_mem)
1991 		return len;
1992 
1993 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1994 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1995 	if (tg_pt_gp) {
1996 		tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1997 		len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1998 			" %hu\nTG Port Primary Access State: %s\nTG Port "
1999 			"Primary Access Status: %s\nTG Port Secondary Access"
2000 			" State: %s\nTG Port Secondary Access Status: %s\n",
2001 			config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
2002 			core_alua_dump_state(atomic_read(
2003 					&tg_pt_gp->tg_pt_gp_alua_access_state)),
2004 			core_alua_dump_status(
2005 				tg_pt_gp->tg_pt_gp_alua_access_status),
2006 			(atomic_read(&port->sep_tg_pt_secondary_offline)) ?
2007 			"Offline" : "None",
2008 			core_alua_dump_status(port->sep_tg_pt_secondary_stat));
2009 	}
2010 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2011 
2012 	return len;
2013 }
2014 
2015 ssize_t core_alua_store_tg_pt_gp_info(
2016 	struct se_port *port,
2017 	const char *page,
2018 	size_t count)
2019 {
2020 	struct se_portal_group *tpg;
2021 	struct se_lun *lun;
2022 	struct se_device *dev = port->sep_lun->lun_se_dev;
2023 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
2024 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2025 	unsigned char buf[TG_PT_GROUP_NAME_BUF];
2026 	int move = 0;
2027 
2028 	tpg = port->sep_tpg;
2029 	lun = port->sep_lun;
2030 
2031 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
2032 	if (!tg_pt_gp_mem)
2033 		return 0;
2034 
2035 	if (count > TG_PT_GROUP_NAME_BUF) {
2036 		pr_err("ALUA Target Port Group alias too large!\n");
2037 		return -EINVAL;
2038 	}
2039 	memset(buf, 0, TG_PT_GROUP_NAME_BUF);
2040 	memcpy(buf, page, count);
2041 	/*
2042 	 * Any ALUA target port group alias besides "NULL" means we will be
2043 	 * making a new group association.
2044 	 */
2045 	if (strcmp(strstrip(buf), "NULL")) {
2046 		/*
2047 		 * core_alua_get_tg_pt_gp_by_name() will increment reference to
2048 		 * struct t10_alua_tg_pt_gp.  This reference is released with
2049 		 * core_alua_put_tg_pt_gp_from_name() below.
2050 		 */
2051 		tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
2052 					strstrip(buf));
2053 		if (!tg_pt_gp_new)
2054 			return -ENODEV;
2055 	}
2056 
2057 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2058 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
2059 	if (tg_pt_gp) {
2060 		/*
2061 		 * Clearing an existing tg_pt_gp association, and replacing
2062 		 * with the default_tg_pt_gp.
2063 		 */
2064 		if (!tg_pt_gp_new) {
2065 			pr_debug("Target_Core_ConfigFS: Moving"
2066 				" %s/tpgt_%hu/%s from ALUA Target Port Group:"
2067 				" alua/%s, ID: %hu back to"
2068 				" default_tg_pt_gp\n",
2069 				tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2070 				tpg->se_tpg_tfo->tpg_get_tag(tpg),
2071 				config_item_name(&lun->lun_group.cg_item),
2072 				config_item_name(
2073 					&tg_pt_gp->tg_pt_gp_group.cg_item),
2074 				tg_pt_gp->tg_pt_gp_id);
2075 
2076 			__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2077 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
2078 					dev->t10_alua.default_tg_pt_gp);
2079 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2080 
2081 			return count;
2082 		}
2083 		/*
2084 		 * Removing existing association of tg_pt_gp_mem with tg_pt_gp
2085 		 */
2086 		__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2087 		move = 1;
2088 	}
2089 	/*
2090 	 * Associate tg_pt_gp_mem with tg_pt_gp_new.
2091 	 */
2092 	__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
2093 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2094 	pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2095 		" Target Port Group: alua/%s, ID: %hu\n", (move) ?
2096 		"Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2097 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
2098 		config_item_name(&lun->lun_group.cg_item),
2099 		config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2100 		tg_pt_gp_new->tg_pt_gp_id);
2101 
2102 	core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2103 	return count;
2104 }
2105 
2106 ssize_t core_alua_show_access_type(
2107 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2108 	char *page)
2109 {
2110 	if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2111 	    (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2112 		return sprintf(page, "Implicit and Explicit\n");
2113 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2114 		return sprintf(page, "Implicit\n");
2115 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2116 		return sprintf(page, "Explicit\n");
2117 	else
2118 		return sprintf(page, "None\n");
2119 }
2120 
2121 ssize_t core_alua_store_access_type(
2122 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2123 	const char *page,
2124 	size_t count)
2125 {
2126 	unsigned long tmp;
2127 	int ret;
2128 
2129 	ret = kstrtoul(page, 0, &tmp);
2130 	if (ret < 0) {
2131 		pr_err("Unable to extract alua_access_type\n");
2132 		return ret;
2133 	}
2134 	if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2135 		pr_err("Illegal value for alua_access_type:"
2136 				" %lu\n", tmp);
2137 		return -EINVAL;
2138 	}
2139 	if (tmp == 3)
2140 		tg_pt_gp->tg_pt_gp_alua_access_type =
2141 			TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2142 	else if (tmp == 2)
2143 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2144 	else if (tmp == 1)
2145 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2146 	else
2147 		tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2148 
2149 	return count;
2150 }
2151 
2152 ssize_t core_alua_show_nonop_delay_msecs(
2153 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2154 	char *page)
2155 {
2156 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2157 }
2158 
2159 ssize_t core_alua_store_nonop_delay_msecs(
2160 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2161 	const char *page,
2162 	size_t count)
2163 {
2164 	unsigned long tmp;
2165 	int ret;
2166 
2167 	ret = kstrtoul(page, 0, &tmp);
2168 	if (ret < 0) {
2169 		pr_err("Unable to extract nonop_delay_msecs\n");
2170 		return ret;
2171 	}
2172 	if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2173 		pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2174 			" ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2175 			ALUA_MAX_NONOP_DELAY_MSECS);
2176 		return -EINVAL;
2177 	}
2178 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2179 
2180 	return count;
2181 }
2182 
2183 ssize_t core_alua_show_trans_delay_msecs(
2184 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2185 	char *page)
2186 {
2187 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2188 }
2189 
2190 ssize_t core_alua_store_trans_delay_msecs(
2191 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2192 	const char *page,
2193 	size_t count)
2194 {
2195 	unsigned long tmp;
2196 	int ret;
2197 
2198 	ret = kstrtoul(page, 0, &tmp);
2199 	if (ret < 0) {
2200 		pr_err("Unable to extract trans_delay_msecs\n");
2201 		return ret;
2202 	}
2203 	if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2204 		pr_err("Passed trans_delay_msecs: %lu, exceeds"
2205 			" ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2206 			ALUA_MAX_TRANS_DELAY_MSECS);
2207 		return -EINVAL;
2208 	}
2209 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2210 
2211 	return count;
2212 }
2213 
2214 ssize_t core_alua_show_implicit_trans_secs(
2215 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2216 	char *page)
2217 {
2218 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2219 }
2220 
2221 ssize_t core_alua_store_implicit_trans_secs(
2222 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2223 	const char *page,
2224 	size_t count)
2225 {
2226 	unsigned long tmp;
2227 	int ret;
2228 
2229 	ret = kstrtoul(page, 0, &tmp);
2230 	if (ret < 0) {
2231 		pr_err("Unable to extract implicit_trans_secs\n");
2232 		return ret;
2233 	}
2234 	if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2235 		pr_err("Passed implicit_trans_secs: %lu, exceeds"
2236 			" ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2237 			ALUA_MAX_IMPLICIT_TRANS_SECS);
2238 		return  -EINVAL;
2239 	}
2240 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2241 
2242 	return count;
2243 }
2244 
2245 ssize_t core_alua_show_preferred_bit(
2246 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2247 	char *page)
2248 {
2249 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2250 }
2251 
2252 ssize_t core_alua_store_preferred_bit(
2253 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2254 	const char *page,
2255 	size_t count)
2256 {
2257 	unsigned long tmp;
2258 	int ret;
2259 
2260 	ret = kstrtoul(page, 0, &tmp);
2261 	if (ret < 0) {
2262 		pr_err("Unable to extract preferred ALUA value\n");
2263 		return ret;
2264 	}
2265 	if ((tmp != 0) && (tmp != 1)) {
2266 		pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2267 		return -EINVAL;
2268 	}
2269 	tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2270 
2271 	return count;
2272 }
2273 
2274 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2275 {
2276 	if (!lun->lun_sep)
2277 		return -ENODEV;
2278 
2279 	return sprintf(page, "%d\n",
2280 		atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
2281 }
2282 
2283 ssize_t core_alua_store_offline_bit(
2284 	struct se_lun *lun,
2285 	const char *page,
2286 	size_t count)
2287 {
2288 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2289 	unsigned long tmp;
2290 	int ret;
2291 
2292 	if (!lun->lun_sep)
2293 		return -ENODEV;
2294 
2295 	ret = kstrtoul(page, 0, &tmp);
2296 	if (ret < 0) {
2297 		pr_err("Unable to extract alua_tg_pt_offline value\n");
2298 		return ret;
2299 	}
2300 	if ((tmp != 0) && (tmp != 1)) {
2301 		pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2302 				tmp);
2303 		return -EINVAL;
2304 	}
2305 	tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
2306 	if (!tg_pt_gp_mem) {
2307 		pr_err("Unable to locate *tg_pt_gp_mem\n");
2308 		return -EINVAL;
2309 	}
2310 
2311 	ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
2312 			lun->lun_sep, 0, (int)tmp);
2313 	if (ret < 0)
2314 		return -EINVAL;
2315 
2316 	return count;
2317 }
2318 
2319 ssize_t core_alua_show_secondary_status(
2320 	struct se_lun *lun,
2321 	char *page)
2322 {
2323 	return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
2324 }
2325 
2326 ssize_t core_alua_store_secondary_status(
2327 	struct se_lun *lun,
2328 	const char *page,
2329 	size_t count)
2330 {
2331 	unsigned long tmp;
2332 	int ret;
2333 
2334 	ret = kstrtoul(page, 0, &tmp);
2335 	if (ret < 0) {
2336 		pr_err("Unable to extract alua_tg_pt_status\n");
2337 		return ret;
2338 	}
2339 	if ((tmp != ALUA_STATUS_NONE) &&
2340 	    (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2341 	    (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2342 		pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2343 				tmp);
2344 		return -EINVAL;
2345 	}
2346 	lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
2347 
2348 	return count;
2349 }
2350 
2351 ssize_t core_alua_show_secondary_write_metadata(
2352 	struct se_lun *lun,
2353 	char *page)
2354 {
2355 	return sprintf(page, "%d\n",
2356 			lun->lun_sep->sep_tg_pt_secondary_write_md);
2357 }
2358 
2359 ssize_t core_alua_store_secondary_write_metadata(
2360 	struct se_lun *lun,
2361 	const char *page,
2362 	size_t count)
2363 {
2364 	unsigned long tmp;
2365 	int ret;
2366 
2367 	ret = kstrtoul(page, 0, &tmp);
2368 	if (ret < 0) {
2369 		pr_err("Unable to extract alua_tg_pt_write_md\n");
2370 		return ret;
2371 	}
2372 	if ((tmp != 0) && (tmp != 1)) {
2373 		pr_err("Illegal value for alua_tg_pt_write_md:"
2374 				" %lu\n", tmp);
2375 		return -EINVAL;
2376 	}
2377 	lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
2378 
2379 	return count;
2380 }
2381 
2382 int core_setup_alua(struct se_device *dev)
2383 {
2384 	if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV &&
2385 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2386 		struct t10_alua_lu_gp_member *lu_gp_mem;
2387 
2388 		/*
2389 		 * Associate this struct se_device with the default ALUA
2390 		 * LUN Group.
2391 		 */
2392 		lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2393 		if (IS_ERR(lu_gp_mem))
2394 			return PTR_ERR(lu_gp_mem);
2395 
2396 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2397 		__core_alua_attach_lu_gp_mem(lu_gp_mem,
2398 				default_lu_gp);
2399 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2400 
2401 		pr_debug("%s: Adding to default ALUA LU Group:"
2402 			" core/alua/lu_gps/default_lu_gp\n",
2403 			dev->transport->name);
2404 	}
2405 
2406 	return 0;
2407 }
2408