xref: /linux/drivers/target/target_core_alua.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
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();
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();
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 	case READ_CAPACITY:
580 		return 0;
581 	case SERVICE_ACTION_IN:
582 		switch (cdb[1] & 0x1f) {
583 		case SAI_READ_CAPACITY_16:
584 			return 0;
585 		default:
586 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
587 			return 1;
588 		}
589 	case MAINTENANCE_IN:
590 		switch (cdb[1] & 0x1f) {
591 		case MI_REPORT_TARGET_PGS:
592 			return 0;
593 		default:
594 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
595 			return 1;
596 		}
597 	case MAINTENANCE_OUT:
598 		switch (cdb[1]) {
599 		case MO_SET_TARGET_PGS:
600 			return 0;
601 		default:
602 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
603 			return 1;
604 		}
605 	case REQUEST_SENSE:
606 	case PERSISTENT_RESERVE_IN:
607 	case PERSISTENT_RESERVE_OUT:
608 	case READ_BUFFER:
609 	case WRITE_BUFFER:
610 		return 0;
611 	default:
612 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
613 		return 1;
614 	}
615 
616 	return 0;
617 }
618 
619 static inline int core_alua_state_unavailable(
620 	struct se_cmd *cmd,
621 	unsigned char *cdb)
622 {
623 	/*
624 	 * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
625 	 * spc4r17 section 5.9.2.4.5
626 	 */
627 	switch (cdb[0]) {
628 	case INQUIRY:
629 	case REPORT_LUNS:
630 		return 0;
631 	case MAINTENANCE_IN:
632 		switch (cdb[1] & 0x1f) {
633 		case MI_REPORT_TARGET_PGS:
634 			return 0;
635 		default:
636 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
637 			return 1;
638 		}
639 	case MAINTENANCE_OUT:
640 		switch (cdb[1]) {
641 		case MO_SET_TARGET_PGS:
642 			return 0;
643 		default:
644 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
645 			return 1;
646 		}
647 	case REQUEST_SENSE:
648 	case READ_BUFFER:
649 	case WRITE_BUFFER:
650 		return 0;
651 	default:
652 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
653 		return 1;
654 	}
655 
656 	return 0;
657 }
658 
659 static inline int core_alua_state_transition(
660 	struct se_cmd *cmd,
661 	unsigned char *cdb)
662 {
663 	/*
664 	 * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
665 	 * spc4r17 section 5.9.2.5
666 	 */
667 	switch (cdb[0]) {
668 	case INQUIRY:
669 	case REPORT_LUNS:
670 		return 0;
671 	case MAINTENANCE_IN:
672 		switch (cdb[1] & 0x1f) {
673 		case MI_REPORT_TARGET_PGS:
674 			return 0;
675 		default:
676 			set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
677 			return 1;
678 		}
679 	case REQUEST_SENSE:
680 	case READ_BUFFER:
681 	case WRITE_BUFFER:
682 		return 0;
683 	default:
684 		set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
685 		return 1;
686 	}
687 
688 	return 0;
689 }
690 
691 /*
692  * return 1: Is used to signal LUN not accessible, and check condition/not ready
693  * return 0: Used to signal success
694  * return -1: Used to signal failure, and invalid cdb field
695  */
696 sense_reason_t
697 target_alua_state_check(struct se_cmd *cmd)
698 {
699 	struct se_device *dev = cmd->se_dev;
700 	unsigned char *cdb = cmd->t_task_cdb;
701 	struct se_lun *lun = cmd->se_lun;
702 	struct se_port *port = lun->lun_sep;
703 	struct t10_alua_tg_pt_gp *tg_pt_gp;
704 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
705 	int out_alua_state, nonop_delay_msecs;
706 
707 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
708 		return 0;
709 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
710 		return 0;
711 
712 	if (!port)
713 		return 0;
714 	/*
715 	 * First, check for a struct se_port specific secondary ALUA target port
716 	 * access state: OFFLINE
717 	 */
718 	if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
719 		pr_debug("ALUA: Got secondary offline status for local"
720 				" target port\n");
721 		set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
722 		return TCM_CHECK_CONDITION_NOT_READY;
723 	}
724 	 /*
725 	 * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
726 	 * ALUA target port group, to obtain current ALUA access state.
727 	 * Otherwise look for the underlying struct se_device association with
728 	 * a ALUA logical unit group.
729 	 */
730 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
731 	if (!tg_pt_gp_mem)
732 		return 0;
733 
734 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
735 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
736 	out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
737 	nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
738 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
739 	/*
740 	 * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
741 	 * statement so the compiler knows explicitly to check this case first.
742 	 * For the Optimized ALUA access state case, we want to process the
743 	 * incoming fabric cmd ASAP..
744 	 */
745 	if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
746 		return 0;
747 
748 	switch (out_alua_state) {
749 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
750 		core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
751 		break;
752 	case ALUA_ACCESS_STATE_STANDBY:
753 		if (core_alua_state_standby(cmd, cdb))
754 			return TCM_CHECK_CONDITION_NOT_READY;
755 		break;
756 	case ALUA_ACCESS_STATE_UNAVAILABLE:
757 		if (core_alua_state_unavailable(cmd, cdb))
758 			return TCM_CHECK_CONDITION_NOT_READY;
759 		break;
760 	case ALUA_ACCESS_STATE_TRANSITION:
761 		if (core_alua_state_transition(cmd, cdb))
762 			return TCM_CHECK_CONDITION_NOT_READY;
763 		break;
764 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
765 		if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
766 			return TCM_CHECK_CONDITION_NOT_READY;
767 		break;
768 	/*
769 	 * OFFLINE is a secondary ALUA target port group access state, that is
770 	 * handled above with struct se_port->sep_tg_pt_secondary_offline=1
771 	 */
772 	case ALUA_ACCESS_STATE_OFFLINE:
773 	default:
774 		pr_err("Unknown ALUA access state: 0x%02x\n",
775 				out_alua_state);
776 		return TCM_INVALID_CDB_FIELD;
777 	}
778 
779 	return 0;
780 }
781 
782 /*
783  * Check implicit and explicit ALUA state change request.
784  */
785 static sense_reason_t
786 core_alua_check_transition(int state, int valid, int *primary)
787 {
788 	/*
789 	 * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
790 	 * defined as primary target port asymmetric access states.
791 	 */
792 	switch (state) {
793 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
794 		if (!(valid & ALUA_AO_SUP))
795 			goto not_supported;
796 		*primary = 1;
797 		break;
798 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
799 		if (!(valid & ALUA_AN_SUP))
800 			goto not_supported;
801 		*primary = 1;
802 		break;
803 	case ALUA_ACCESS_STATE_STANDBY:
804 		if (!(valid & ALUA_S_SUP))
805 			goto not_supported;
806 		*primary = 1;
807 		break;
808 	case ALUA_ACCESS_STATE_UNAVAILABLE:
809 		if (!(valid & ALUA_U_SUP))
810 			goto not_supported;
811 		*primary = 1;
812 		break;
813 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
814 		if (!(valid & ALUA_LBD_SUP))
815 			goto not_supported;
816 		*primary = 1;
817 		break;
818 	case ALUA_ACCESS_STATE_OFFLINE:
819 		/*
820 		 * OFFLINE state is defined as a secondary target port
821 		 * asymmetric access state.
822 		 */
823 		if (!(valid & ALUA_O_SUP))
824 			goto not_supported;
825 		*primary = 0;
826 		break;
827 	case ALUA_ACCESS_STATE_TRANSITION:
828 		/*
829 		 * Transitioning is set internally, and
830 		 * cannot be selected manually.
831 		 */
832 		goto not_supported;
833 	default:
834 		pr_err("Unknown ALUA access state: 0x%02x\n", state);
835 		return TCM_INVALID_PARAMETER_LIST;
836 	}
837 
838 	return 0;
839 
840 not_supported:
841 	pr_err("ALUA access state %s not supported",
842 	       core_alua_dump_state(state));
843 	return TCM_INVALID_PARAMETER_LIST;
844 }
845 
846 static char *core_alua_dump_state(int state)
847 {
848 	switch (state) {
849 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
850 		return "Active/Optimized";
851 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
852 		return "Active/NonOptimized";
853 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
854 		return "LBA Dependent";
855 	case ALUA_ACCESS_STATE_STANDBY:
856 		return "Standby";
857 	case ALUA_ACCESS_STATE_UNAVAILABLE:
858 		return "Unavailable";
859 	case ALUA_ACCESS_STATE_OFFLINE:
860 		return "Offline";
861 	case ALUA_ACCESS_STATE_TRANSITION:
862 		return "Transitioning";
863 	default:
864 		return "Unknown";
865 	}
866 
867 	return NULL;
868 }
869 
870 char *core_alua_dump_status(int status)
871 {
872 	switch (status) {
873 	case ALUA_STATUS_NONE:
874 		return "None";
875 	case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
876 		return "Altered by Explicit STPG";
877 	case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
878 		return "Altered by Implicit ALUA";
879 	default:
880 		return "Unknown";
881 	}
882 
883 	return NULL;
884 }
885 
886 /*
887  * Used by fabric modules to determine when we need to delay processing
888  * for the Active/NonOptimized paths..
889  */
890 int core_alua_check_nonop_delay(
891 	struct se_cmd *cmd)
892 {
893 	if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
894 		return 0;
895 	if (in_interrupt())
896 		return 0;
897 	/*
898 	 * The ALUA Active/NonOptimized access state delay can be disabled
899 	 * in via configfs with a value of zero
900 	 */
901 	if (!cmd->alua_nonop_delay)
902 		return 0;
903 	/*
904 	 * struct se_cmd->alua_nonop_delay gets set by a target port group
905 	 * defined interval in core_alua_state_nonoptimized()
906 	 */
907 	msleep_interruptible(cmd->alua_nonop_delay);
908 	return 0;
909 }
910 EXPORT_SYMBOL(core_alua_check_nonop_delay);
911 
912 /*
913  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
914  *
915  */
916 static int core_alua_write_tpg_metadata(
917 	const char *path,
918 	unsigned char *md_buf,
919 	u32 md_buf_len)
920 {
921 	struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
922 	int ret;
923 
924 	if (IS_ERR(file)) {
925 		pr_err("filp_open(%s) for ALUA metadata failed\n", path);
926 		return -ENODEV;
927 	}
928 	ret = kernel_write(file, md_buf, md_buf_len, 0);
929 	if (ret < 0)
930 		pr_err("Error writing ALUA metadata file: %s\n", path);
931 	fput(file);
932 	return (ret < 0) ? -EIO : 0;
933 }
934 
935 /*
936  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
937  */
938 static int core_alua_update_tpg_primary_metadata(
939 	struct t10_alua_tg_pt_gp *tg_pt_gp)
940 {
941 	unsigned char *md_buf;
942 	struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
943 	char path[ALUA_METADATA_PATH_LEN];
944 	int len, rc;
945 
946 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
947 	if (!md_buf) {
948 		pr_err("Unable to allocate buf for ALUA metadata\n");
949 		return -ENOMEM;
950 	}
951 
952 	memset(path, 0, ALUA_METADATA_PATH_LEN);
953 
954 	len = snprintf(md_buf, ALUA_MD_BUF_LEN,
955 			"tg_pt_gp_id=%hu\n"
956 			"alua_access_state=0x%02x\n"
957 			"alua_access_status=0x%02x\n",
958 			tg_pt_gp->tg_pt_gp_id,
959 			tg_pt_gp->tg_pt_gp_alua_pending_state,
960 			tg_pt_gp->tg_pt_gp_alua_access_status);
961 
962 	snprintf(path, ALUA_METADATA_PATH_LEN,
963 		"/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
964 		config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
965 
966 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
967 	kfree(md_buf);
968 	return rc;
969 }
970 
971 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
972 {
973 	struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
974 		struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work.work);
975 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
976 	struct se_dev_entry *se_deve;
977 	struct se_lun_acl *lacl;
978 	struct se_port *port;
979 	struct t10_alua_tg_pt_gp_member *mem;
980 	bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
981 			 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
982 
983 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
984 	list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
985 				tg_pt_gp_mem_list) {
986 		port = mem->tg_pt;
987 		/*
988 		 * After an implicit target port asymmetric access state
989 		 * change, a device server shall establish a unit attention
990 		 * condition for the initiator port associated with every I_T
991 		 * nexus with the additional sense code set to ASYMMETRIC
992 		 * ACCESS STATE CHANGED.
993 		 *
994 		 * After an explicit target port asymmetric access state
995 		 * change, a device server shall establish a unit attention
996 		 * condition with the additional sense code set to ASYMMETRIC
997 		 * ACCESS STATE CHANGED for the initiator port associated with
998 		 * every I_T nexus other than the I_T nexus on which the SET
999 		 * TARGET PORT GROUPS command
1000 		 */
1001 		atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
1002 		smp_mb__after_atomic();
1003 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1004 
1005 		spin_lock_bh(&port->sep_alua_lock);
1006 		list_for_each_entry(se_deve, &port->sep_alua_list,
1007 					alua_port_list) {
1008 			lacl = se_deve->se_lun_acl;
1009 			/*
1010 			 * se_deve->se_lun_acl pointer may be NULL for a
1011 			 * entry created without explicit Node+MappedLUN ACLs
1012 			 */
1013 			if (!lacl)
1014 				continue;
1015 
1016 			if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
1017 			     ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
1018 			   (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1019 			    (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl) &&
1020 			   (tg_pt_gp->tg_pt_gp_alua_port != NULL) &&
1021 			    (tg_pt_gp->tg_pt_gp_alua_port == port))
1022 				continue;
1023 
1024 			core_scsi3_ua_allocate(lacl->se_lun_nacl,
1025 				se_deve->mapped_lun, 0x2A,
1026 				ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1027 		}
1028 		spin_unlock_bh(&port->sep_alua_lock);
1029 
1030 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1031 		atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
1032 		smp_mb__after_atomic();
1033 	}
1034 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1035 	/*
1036 	 * Update the ALUA metadata buf that has been allocated in
1037 	 * core_alua_do_port_transition(), this metadata will be written
1038 	 * to struct file.
1039 	 *
1040 	 * Note that there is the case where we do not want to update the
1041 	 * metadata when the saved metadata is being parsed in userspace
1042 	 * when setting the existing port access state and access status.
1043 	 *
1044 	 * Also note that the failure to write out the ALUA metadata to
1045 	 * struct file does NOT affect the actual ALUA transition.
1046 	 */
1047 	if (tg_pt_gp->tg_pt_gp_write_metadata) {
1048 		mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1049 		core_alua_update_tpg_primary_metadata(tg_pt_gp);
1050 		mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1051 	}
1052 	/*
1053 	 * Set the current primary ALUA access state to the requested new state
1054 	 */
1055 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1056 		   tg_pt_gp->tg_pt_gp_alua_pending_state);
1057 
1058 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1059 		" from primary access state %s to %s\n", (explicit) ? "explicit" :
1060 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1061 		tg_pt_gp->tg_pt_gp_id,
1062 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1063 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1064 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1065 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1066 	smp_mb__after_atomic();
1067 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1068 
1069 	if (tg_pt_gp->tg_pt_gp_transition_complete)
1070 		complete(tg_pt_gp->tg_pt_gp_transition_complete);
1071 }
1072 
1073 static int core_alua_do_transition_tg_pt(
1074 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1075 	int new_state,
1076 	int explicit)
1077 {
1078 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1079 	DECLARE_COMPLETION_ONSTACK(wait);
1080 
1081 	/* Nothing to be done here */
1082 	if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1083 		return 0;
1084 
1085 	if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1086 		return -EAGAIN;
1087 
1088 	/*
1089 	 * Flush any pending transitions
1090 	 */
1091 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs &&
1092 	    atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
1093 	    ALUA_ACCESS_STATE_TRANSITION) {
1094 		/* Just in case */
1095 		tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1096 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1097 		flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1098 		wait_for_completion(&wait);
1099 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1100 		return 0;
1101 	}
1102 
1103 	/*
1104 	 * Save the old primary ALUA access state, and set the current state
1105 	 * to ALUA_ACCESS_STATE_TRANSITION.
1106 	 */
1107 	tg_pt_gp->tg_pt_gp_alua_previous_state =
1108 		atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1109 	tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1110 
1111 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1112 			ALUA_ACCESS_STATE_TRANSITION);
1113 	tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1114 				ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1115 				ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1116 
1117 	/*
1118 	 * Check for the optional ALUA primary state transition delay
1119 	 */
1120 	if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1121 		msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1122 
1123 	/*
1124 	 * Take a reference for workqueue item
1125 	 */
1126 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1127 	atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1128 	smp_mb__after_atomic();
1129 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1130 
1131 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs) {
1132 		unsigned long transition_tmo;
1133 
1134 		transition_tmo = tg_pt_gp->tg_pt_gp_implicit_trans_secs * HZ;
1135 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1136 				   &tg_pt_gp->tg_pt_gp_transition_work,
1137 				   transition_tmo);
1138 	} else {
1139 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1140 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1141 				   &tg_pt_gp->tg_pt_gp_transition_work, 0);
1142 		wait_for_completion(&wait);
1143 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1144 	}
1145 
1146 	return 0;
1147 }
1148 
1149 int core_alua_do_port_transition(
1150 	struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1151 	struct se_device *l_dev,
1152 	struct se_port *l_port,
1153 	struct se_node_acl *l_nacl,
1154 	int new_state,
1155 	int explicit)
1156 {
1157 	struct se_device *dev;
1158 	struct t10_alua_lu_gp *lu_gp;
1159 	struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1160 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1161 	int primary, valid_states, rc = 0;
1162 
1163 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1164 	if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1165 		return -EINVAL;
1166 
1167 	local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1168 	spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1169 	lu_gp = local_lu_gp_mem->lu_gp;
1170 	atomic_inc(&lu_gp->lu_gp_ref_cnt);
1171 	smp_mb__after_atomic();
1172 	spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1173 	/*
1174 	 * For storage objects that are members of the 'default_lu_gp',
1175 	 * we only do transition on the passed *l_tp_pt_gp, and not
1176 	 * on all of the matching target port groups IDs in default_lu_gp.
1177 	 */
1178 	if (!lu_gp->lu_gp_id) {
1179 		/*
1180 		 * core_alua_do_transition_tg_pt() will always return
1181 		 * success.
1182 		 */
1183 		l_tg_pt_gp->tg_pt_gp_alua_port = l_port;
1184 		l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1185 		rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1186 						   new_state, explicit);
1187 		atomic_dec(&lu_gp->lu_gp_ref_cnt);
1188 		smp_mb__after_atomic();
1189 		return rc;
1190 	}
1191 	/*
1192 	 * For all other LU groups aside from 'default_lu_gp', walk all of
1193 	 * the associated storage objects looking for a matching target port
1194 	 * group ID from the local target port group.
1195 	 */
1196 	spin_lock(&lu_gp->lu_gp_lock);
1197 	list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1198 				lu_gp_mem_list) {
1199 
1200 		dev = lu_gp_mem->lu_gp_mem_dev;
1201 		atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
1202 		smp_mb__after_atomic();
1203 		spin_unlock(&lu_gp->lu_gp_lock);
1204 
1205 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1206 		list_for_each_entry(tg_pt_gp,
1207 				&dev->t10_alua.tg_pt_gps_list,
1208 				tg_pt_gp_list) {
1209 
1210 			if (!tg_pt_gp->tg_pt_gp_valid_id)
1211 				continue;
1212 			/*
1213 			 * If the target behavior port asymmetric access state
1214 			 * is changed for any target port group accessible via
1215 			 * a logical unit within a LU group, the target port
1216 			 * behavior group asymmetric access states for the same
1217 			 * target port group accessible via other logical units
1218 			 * in that LU group will also change.
1219 			 */
1220 			if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1221 				continue;
1222 
1223 			if (l_tg_pt_gp == tg_pt_gp) {
1224 				tg_pt_gp->tg_pt_gp_alua_port = l_port;
1225 				tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1226 			} else {
1227 				tg_pt_gp->tg_pt_gp_alua_port = NULL;
1228 				tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1229 			}
1230 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1231 			smp_mb__after_atomic();
1232 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1233 			/*
1234 			 * core_alua_do_transition_tg_pt() will always return
1235 			 * success.
1236 			 */
1237 			rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1238 					new_state, explicit);
1239 
1240 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1241 			atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1242 			smp_mb__after_atomic();
1243 			if (rc)
1244 				break;
1245 		}
1246 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1247 
1248 		spin_lock(&lu_gp->lu_gp_lock);
1249 		atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
1250 		smp_mb__after_atomic();
1251 	}
1252 	spin_unlock(&lu_gp->lu_gp_lock);
1253 
1254 	if (!rc) {
1255 		pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1256 			 " Group IDs: %hu %s transition to primary state: %s\n",
1257 			 config_item_name(&lu_gp->lu_gp_group.cg_item),
1258 			 l_tg_pt_gp->tg_pt_gp_id,
1259 			 (explicit) ? "explicit" : "implicit",
1260 			 core_alua_dump_state(new_state));
1261 	}
1262 
1263 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1264 	smp_mb__after_atomic();
1265 	return rc;
1266 }
1267 
1268 /*
1269  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
1270  */
1271 static int core_alua_update_tpg_secondary_metadata(
1272 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1273 	struct se_port *port)
1274 {
1275 	unsigned char *md_buf;
1276 	struct se_portal_group *se_tpg = port->sep_tpg;
1277 	char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1278 	int len, rc;
1279 
1280 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1281 	if (!md_buf) {
1282 		pr_err("Unable to allocate buf for ALUA metadata\n");
1283 		return -ENOMEM;
1284 	}
1285 
1286 	memset(path, 0, ALUA_METADATA_PATH_LEN);
1287 	memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1288 
1289 	len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1290 			se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1291 
1292 	if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1293 		snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1294 				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1295 
1296 	len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1297 			"alua_tg_pt_status=0x%02x\n",
1298 			atomic_read(&port->sep_tg_pt_secondary_offline),
1299 			port->sep_tg_pt_secondary_stat);
1300 
1301 	snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
1302 			se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1303 			port->sep_lun->unpacked_lun);
1304 
1305 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
1306 	kfree(md_buf);
1307 
1308 	return rc;
1309 }
1310 
1311 static int core_alua_set_tg_pt_secondary_state(
1312 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1313 	struct se_port *port,
1314 	int explicit,
1315 	int offline)
1316 {
1317 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1318 	int trans_delay_msecs;
1319 
1320 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1321 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1322 	if (!tg_pt_gp) {
1323 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1324 		pr_err("Unable to complete secondary state"
1325 				" transition\n");
1326 		return -EINVAL;
1327 	}
1328 	trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1329 	/*
1330 	 * Set the secondary ALUA target port access state to OFFLINE
1331 	 * or release the previously secondary state for struct se_port
1332 	 */
1333 	if (offline)
1334 		atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1335 	else
1336 		atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1337 
1338 	port->sep_tg_pt_secondary_stat = (explicit) ?
1339 			ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1340 			ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1341 
1342 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1343 		" to secondary access state: %s\n", (explicit) ? "explicit" :
1344 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1345 		tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1346 
1347 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1348 	/*
1349 	 * Do the optional transition delay after we set the secondary
1350 	 * ALUA access state.
1351 	 */
1352 	if (trans_delay_msecs != 0)
1353 		msleep_interruptible(trans_delay_msecs);
1354 	/*
1355 	 * See if we need to update the ALUA fabric port metadata for
1356 	 * secondary state and status
1357 	 */
1358 	if (port->sep_tg_pt_secondary_write_md) {
1359 		mutex_lock(&port->sep_tg_pt_md_mutex);
1360 		core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port);
1361 		mutex_unlock(&port->sep_tg_pt_md_mutex);
1362 	}
1363 
1364 	return 0;
1365 }
1366 
1367 struct t10_alua_lba_map *
1368 core_alua_allocate_lba_map(struct list_head *list,
1369 			   u64 first_lba, u64 last_lba)
1370 {
1371 	struct t10_alua_lba_map *lba_map;
1372 
1373 	lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1374 	if (!lba_map) {
1375 		pr_err("Unable to allocate struct t10_alua_lba_map\n");
1376 		return ERR_PTR(-ENOMEM);
1377 	}
1378 	INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1379 	lba_map->lba_map_first_lba = first_lba;
1380 	lba_map->lba_map_last_lba = last_lba;
1381 
1382 	list_add_tail(&lba_map->lba_map_list, list);
1383 	return lba_map;
1384 }
1385 
1386 int
1387 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1388 			       int pg_id, int state)
1389 {
1390 	struct t10_alua_lba_map_member *lba_map_mem;
1391 
1392 	list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1393 			    lba_map_mem_list) {
1394 		if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1395 			pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1396 			return -EINVAL;
1397 		}
1398 	}
1399 
1400 	lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1401 	if (!lba_map_mem) {
1402 		pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1403 		return -ENOMEM;
1404 	}
1405 	lba_map_mem->lba_map_mem_alua_state = state;
1406 	lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1407 
1408 	list_add_tail(&lba_map_mem->lba_map_mem_list,
1409 		      &lba_map->lba_map_mem_list);
1410 	return 0;
1411 }
1412 
1413 void
1414 core_alua_free_lba_map(struct list_head *lba_list)
1415 {
1416 	struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1417 	struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1418 
1419 	list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1420 				 lba_map_list) {
1421 		list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1422 					 &lba_map->lba_map_mem_list,
1423 					 lba_map_mem_list) {
1424 			list_del(&lba_map_mem->lba_map_mem_list);
1425 			kmem_cache_free(t10_alua_lba_map_mem_cache,
1426 					lba_map_mem);
1427 		}
1428 		list_del(&lba_map->lba_map_list);
1429 		kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1430 	}
1431 }
1432 
1433 void
1434 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1435 		      int segment_size, int segment_mult)
1436 {
1437 	struct list_head old_lba_map_list;
1438 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1439 	int activate = 0, supported;
1440 
1441 	INIT_LIST_HEAD(&old_lba_map_list);
1442 	spin_lock(&dev->t10_alua.lba_map_lock);
1443 	dev->t10_alua.lba_map_segment_size = segment_size;
1444 	dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1445 	list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1446 	if (lba_map_list) {
1447 		list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1448 		activate = 1;
1449 	}
1450 	spin_unlock(&dev->t10_alua.lba_map_lock);
1451 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1452 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1453 			    tg_pt_gp_list) {
1454 
1455 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1456 			continue;
1457 		supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1458 		if (activate)
1459 			supported |= ALUA_LBD_SUP;
1460 		else
1461 			supported &= ~ALUA_LBD_SUP;
1462 		tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1463 	}
1464 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1465 	core_alua_free_lba_map(&old_lba_map_list);
1466 }
1467 
1468 struct t10_alua_lu_gp *
1469 core_alua_allocate_lu_gp(const char *name, int def_group)
1470 {
1471 	struct t10_alua_lu_gp *lu_gp;
1472 
1473 	lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1474 	if (!lu_gp) {
1475 		pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1476 		return ERR_PTR(-ENOMEM);
1477 	}
1478 	INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1479 	INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1480 	spin_lock_init(&lu_gp->lu_gp_lock);
1481 	atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1482 
1483 	if (def_group) {
1484 		lu_gp->lu_gp_id = alua_lu_gps_counter++;
1485 		lu_gp->lu_gp_valid_id = 1;
1486 		alua_lu_gps_count++;
1487 	}
1488 
1489 	return lu_gp;
1490 }
1491 
1492 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1493 {
1494 	struct t10_alua_lu_gp *lu_gp_tmp;
1495 	u16 lu_gp_id_tmp;
1496 	/*
1497 	 * The lu_gp->lu_gp_id may only be set once..
1498 	 */
1499 	if (lu_gp->lu_gp_valid_id) {
1500 		pr_warn("ALUA LU Group already has a valid ID,"
1501 			" ignoring request\n");
1502 		return -EINVAL;
1503 	}
1504 
1505 	spin_lock(&lu_gps_lock);
1506 	if (alua_lu_gps_count == 0x0000ffff) {
1507 		pr_err("Maximum ALUA alua_lu_gps_count:"
1508 				" 0x0000ffff reached\n");
1509 		spin_unlock(&lu_gps_lock);
1510 		kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1511 		return -ENOSPC;
1512 	}
1513 again:
1514 	lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1515 				alua_lu_gps_counter++;
1516 
1517 	list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1518 		if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1519 			if (!lu_gp_id)
1520 				goto again;
1521 
1522 			pr_warn("ALUA Logical Unit Group ID: %hu"
1523 				" already exists, ignoring request\n",
1524 				lu_gp_id);
1525 			spin_unlock(&lu_gps_lock);
1526 			return -EINVAL;
1527 		}
1528 	}
1529 
1530 	lu_gp->lu_gp_id = lu_gp_id_tmp;
1531 	lu_gp->lu_gp_valid_id = 1;
1532 	list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1533 	alua_lu_gps_count++;
1534 	spin_unlock(&lu_gps_lock);
1535 
1536 	return 0;
1537 }
1538 
1539 static struct t10_alua_lu_gp_member *
1540 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1541 {
1542 	struct t10_alua_lu_gp_member *lu_gp_mem;
1543 
1544 	lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1545 	if (!lu_gp_mem) {
1546 		pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1547 		return ERR_PTR(-ENOMEM);
1548 	}
1549 	INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1550 	spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1551 	atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1552 
1553 	lu_gp_mem->lu_gp_mem_dev = dev;
1554 	dev->dev_alua_lu_gp_mem = lu_gp_mem;
1555 
1556 	return lu_gp_mem;
1557 }
1558 
1559 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1560 {
1561 	struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1562 	/*
1563 	 * Once we have reached this point, config_item_put() has
1564 	 * already been called from target_core_alua_drop_lu_gp().
1565 	 *
1566 	 * Here, we remove the *lu_gp from the global list so that
1567 	 * no associations can be made while we are releasing
1568 	 * struct t10_alua_lu_gp.
1569 	 */
1570 	spin_lock(&lu_gps_lock);
1571 	list_del(&lu_gp->lu_gp_node);
1572 	alua_lu_gps_count--;
1573 	spin_unlock(&lu_gps_lock);
1574 	/*
1575 	 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1576 	 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1577 	 * released with core_alua_put_lu_gp_from_name()
1578 	 */
1579 	while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1580 		cpu_relax();
1581 	/*
1582 	 * Release reference to struct t10_alua_lu_gp * from all associated
1583 	 * struct se_device.
1584 	 */
1585 	spin_lock(&lu_gp->lu_gp_lock);
1586 	list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1587 				&lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1588 		if (lu_gp_mem->lu_gp_assoc) {
1589 			list_del(&lu_gp_mem->lu_gp_mem_list);
1590 			lu_gp->lu_gp_members--;
1591 			lu_gp_mem->lu_gp_assoc = 0;
1592 		}
1593 		spin_unlock(&lu_gp->lu_gp_lock);
1594 		/*
1595 		 *
1596 		 * lu_gp_mem is associated with a single
1597 		 * struct se_device->dev_alua_lu_gp_mem, and is released when
1598 		 * struct se_device is released via core_alua_free_lu_gp_mem().
1599 		 *
1600 		 * If the passed lu_gp does NOT match the default_lu_gp, assume
1601 		 * we want to re-associate a given lu_gp_mem with default_lu_gp.
1602 		 */
1603 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1604 		if (lu_gp != default_lu_gp)
1605 			__core_alua_attach_lu_gp_mem(lu_gp_mem,
1606 					default_lu_gp);
1607 		else
1608 			lu_gp_mem->lu_gp = NULL;
1609 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1610 
1611 		spin_lock(&lu_gp->lu_gp_lock);
1612 	}
1613 	spin_unlock(&lu_gp->lu_gp_lock);
1614 
1615 	kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1616 }
1617 
1618 void core_alua_free_lu_gp_mem(struct se_device *dev)
1619 {
1620 	struct t10_alua_lu_gp *lu_gp;
1621 	struct t10_alua_lu_gp_member *lu_gp_mem;
1622 
1623 	lu_gp_mem = dev->dev_alua_lu_gp_mem;
1624 	if (!lu_gp_mem)
1625 		return;
1626 
1627 	while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1628 		cpu_relax();
1629 
1630 	spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1631 	lu_gp = lu_gp_mem->lu_gp;
1632 	if (lu_gp) {
1633 		spin_lock(&lu_gp->lu_gp_lock);
1634 		if (lu_gp_mem->lu_gp_assoc) {
1635 			list_del(&lu_gp_mem->lu_gp_mem_list);
1636 			lu_gp->lu_gp_members--;
1637 			lu_gp_mem->lu_gp_assoc = 0;
1638 		}
1639 		spin_unlock(&lu_gp->lu_gp_lock);
1640 		lu_gp_mem->lu_gp = NULL;
1641 	}
1642 	spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1643 
1644 	kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1645 }
1646 
1647 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1648 {
1649 	struct t10_alua_lu_gp *lu_gp;
1650 	struct config_item *ci;
1651 
1652 	spin_lock(&lu_gps_lock);
1653 	list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1654 		if (!lu_gp->lu_gp_valid_id)
1655 			continue;
1656 		ci = &lu_gp->lu_gp_group.cg_item;
1657 		if (!strcmp(config_item_name(ci), name)) {
1658 			atomic_inc(&lu_gp->lu_gp_ref_cnt);
1659 			spin_unlock(&lu_gps_lock);
1660 			return lu_gp;
1661 		}
1662 	}
1663 	spin_unlock(&lu_gps_lock);
1664 
1665 	return NULL;
1666 }
1667 
1668 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1669 {
1670 	spin_lock(&lu_gps_lock);
1671 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1672 	spin_unlock(&lu_gps_lock);
1673 }
1674 
1675 /*
1676  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1677  */
1678 void __core_alua_attach_lu_gp_mem(
1679 	struct t10_alua_lu_gp_member *lu_gp_mem,
1680 	struct t10_alua_lu_gp *lu_gp)
1681 {
1682 	spin_lock(&lu_gp->lu_gp_lock);
1683 	lu_gp_mem->lu_gp = lu_gp;
1684 	lu_gp_mem->lu_gp_assoc = 1;
1685 	list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1686 	lu_gp->lu_gp_members++;
1687 	spin_unlock(&lu_gp->lu_gp_lock);
1688 }
1689 
1690 /*
1691  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1692  */
1693 void __core_alua_drop_lu_gp_mem(
1694 	struct t10_alua_lu_gp_member *lu_gp_mem,
1695 	struct t10_alua_lu_gp *lu_gp)
1696 {
1697 	spin_lock(&lu_gp->lu_gp_lock);
1698 	list_del(&lu_gp_mem->lu_gp_mem_list);
1699 	lu_gp_mem->lu_gp = NULL;
1700 	lu_gp_mem->lu_gp_assoc = 0;
1701 	lu_gp->lu_gp_members--;
1702 	spin_unlock(&lu_gp->lu_gp_lock);
1703 }
1704 
1705 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1706 		const char *name, int def_group)
1707 {
1708 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1709 
1710 	tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1711 	if (!tg_pt_gp) {
1712 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1713 		return NULL;
1714 	}
1715 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1716 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1717 	mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1718 	spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1719 	atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1720 	INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1721 			  core_alua_do_transition_tg_pt_work);
1722 	tg_pt_gp->tg_pt_gp_dev = dev;
1723 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1724 		ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1725 	/*
1726 	 * Enable both explicit and implicit ALUA support by default
1727 	 */
1728 	tg_pt_gp->tg_pt_gp_alua_access_type =
1729 			TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1730 	/*
1731 	 * Set the default Active/NonOptimized Delay in milliseconds
1732 	 */
1733 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1734 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1735 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1736 
1737 	/*
1738 	 * Enable all supported states
1739 	 */
1740 	tg_pt_gp->tg_pt_gp_alua_supported_states =
1741 	    ALUA_T_SUP | ALUA_O_SUP |
1742 	    ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1743 
1744 	if (def_group) {
1745 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1746 		tg_pt_gp->tg_pt_gp_id =
1747 				dev->t10_alua.alua_tg_pt_gps_counter++;
1748 		tg_pt_gp->tg_pt_gp_valid_id = 1;
1749 		dev->t10_alua.alua_tg_pt_gps_count++;
1750 		list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1751 			      &dev->t10_alua.tg_pt_gps_list);
1752 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1753 	}
1754 
1755 	return tg_pt_gp;
1756 }
1757 
1758 int core_alua_set_tg_pt_gp_id(
1759 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1760 	u16 tg_pt_gp_id)
1761 {
1762 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1763 	struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1764 	u16 tg_pt_gp_id_tmp;
1765 
1766 	/*
1767 	 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1768 	 */
1769 	if (tg_pt_gp->tg_pt_gp_valid_id) {
1770 		pr_warn("ALUA TG PT Group already has a valid ID,"
1771 			" ignoring request\n");
1772 		return -EINVAL;
1773 	}
1774 
1775 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1776 	if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1777 		pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1778 			" 0x0000ffff reached\n");
1779 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1780 		kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1781 		return -ENOSPC;
1782 	}
1783 again:
1784 	tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1785 			dev->t10_alua.alua_tg_pt_gps_counter++;
1786 
1787 	list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1788 			tg_pt_gp_list) {
1789 		if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1790 			if (!tg_pt_gp_id)
1791 				goto again;
1792 
1793 			pr_err("ALUA Target Port Group ID: %hu already"
1794 				" exists, ignoring request\n", tg_pt_gp_id);
1795 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1796 			return -EINVAL;
1797 		}
1798 	}
1799 
1800 	tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1801 	tg_pt_gp->tg_pt_gp_valid_id = 1;
1802 	list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1803 			&dev->t10_alua.tg_pt_gps_list);
1804 	dev->t10_alua.alua_tg_pt_gps_count++;
1805 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1806 
1807 	return 0;
1808 }
1809 
1810 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1811 	struct se_port *port)
1812 {
1813 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1814 
1815 	tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1816 				GFP_KERNEL);
1817 	if (!tg_pt_gp_mem) {
1818 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1819 		return ERR_PTR(-ENOMEM);
1820 	}
1821 	INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1822 	spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1823 	atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1824 
1825 	tg_pt_gp_mem->tg_pt = port;
1826 	port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1827 
1828 	return tg_pt_gp_mem;
1829 }
1830 
1831 void core_alua_free_tg_pt_gp(
1832 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1833 {
1834 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1835 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1836 
1837 	/*
1838 	 * Once we have reached this point, config_item_put() has already
1839 	 * been called from target_core_alua_drop_tg_pt_gp().
1840 	 *
1841 	 * Here we remove *tg_pt_gp from the global list so that
1842 	 * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1843 	 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1844 	 */
1845 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1846 	list_del(&tg_pt_gp->tg_pt_gp_list);
1847 	dev->t10_alua.alua_tg_pt_gps_counter--;
1848 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1849 
1850 	flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1851 
1852 	/*
1853 	 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1854 	 * core_alua_get_tg_pt_gp_by_name() in
1855 	 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1856 	 * to be released with core_alua_put_tg_pt_gp_from_name().
1857 	 */
1858 	while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1859 		cpu_relax();
1860 
1861 	/*
1862 	 * Release reference to struct t10_alua_tg_pt_gp from all associated
1863 	 * struct se_port.
1864 	 */
1865 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1866 	list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1867 			&tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1868 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1869 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1870 			tg_pt_gp->tg_pt_gp_members--;
1871 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1872 		}
1873 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1874 		/*
1875 		 * tg_pt_gp_mem is associated with a single
1876 		 * se_port->sep_alua_tg_pt_gp_mem, and is released via
1877 		 * core_alua_free_tg_pt_gp_mem().
1878 		 *
1879 		 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1880 		 * assume we want to re-associate a given tg_pt_gp_mem with
1881 		 * default_tg_pt_gp.
1882 		 */
1883 		spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1884 		if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1885 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1886 					dev->t10_alua.default_tg_pt_gp);
1887 		} else
1888 			tg_pt_gp_mem->tg_pt_gp = NULL;
1889 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1890 
1891 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1892 	}
1893 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1894 
1895 	kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1896 }
1897 
1898 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1899 {
1900 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1901 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1902 
1903 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1904 	if (!tg_pt_gp_mem)
1905 		return;
1906 
1907 	while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1908 		cpu_relax();
1909 
1910 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1911 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1912 	if (tg_pt_gp) {
1913 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1914 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1915 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1916 			tg_pt_gp->tg_pt_gp_members--;
1917 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1918 		}
1919 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1920 		tg_pt_gp_mem->tg_pt_gp = NULL;
1921 	}
1922 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1923 
1924 	kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1925 }
1926 
1927 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1928 		struct se_device *dev, const char *name)
1929 {
1930 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1931 	struct config_item *ci;
1932 
1933 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1934 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1935 			tg_pt_gp_list) {
1936 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1937 			continue;
1938 		ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1939 		if (!strcmp(config_item_name(ci), name)) {
1940 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1941 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1942 			return tg_pt_gp;
1943 		}
1944 	}
1945 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1946 
1947 	return NULL;
1948 }
1949 
1950 static void core_alua_put_tg_pt_gp_from_name(
1951 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1952 {
1953 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1954 
1955 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1956 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1957 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1958 }
1959 
1960 /*
1961  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1962  */
1963 void __core_alua_attach_tg_pt_gp_mem(
1964 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1965 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1966 {
1967 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1968 	tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1969 	tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1970 	list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1971 			&tg_pt_gp->tg_pt_gp_mem_list);
1972 	tg_pt_gp->tg_pt_gp_members++;
1973 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1974 }
1975 
1976 /*
1977  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1978  */
1979 static void __core_alua_drop_tg_pt_gp_mem(
1980 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1981 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1982 {
1983 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1984 	list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1985 	tg_pt_gp_mem->tg_pt_gp = NULL;
1986 	tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1987 	tg_pt_gp->tg_pt_gp_members--;
1988 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1989 }
1990 
1991 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1992 {
1993 	struct config_item *tg_pt_ci;
1994 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1995 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1996 	ssize_t len = 0;
1997 
1998 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1999 	if (!tg_pt_gp_mem)
2000 		return len;
2001 
2002 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2003 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
2004 	if (tg_pt_gp) {
2005 		tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
2006 		len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
2007 			" %hu\nTG Port Primary Access State: %s\nTG Port "
2008 			"Primary Access Status: %s\nTG Port Secondary Access"
2009 			" State: %s\nTG Port Secondary Access Status: %s\n",
2010 			config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
2011 			core_alua_dump_state(atomic_read(
2012 					&tg_pt_gp->tg_pt_gp_alua_access_state)),
2013 			core_alua_dump_status(
2014 				tg_pt_gp->tg_pt_gp_alua_access_status),
2015 			(atomic_read(&port->sep_tg_pt_secondary_offline)) ?
2016 			"Offline" : "None",
2017 			core_alua_dump_status(port->sep_tg_pt_secondary_stat));
2018 	}
2019 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2020 
2021 	return len;
2022 }
2023 
2024 ssize_t core_alua_store_tg_pt_gp_info(
2025 	struct se_port *port,
2026 	const char *page,
2027 	size_t count)
2028 {
2029 	struct se_portal_group *tpg;
2030 	struct se_lun *lun;
2031 	struct se_device *dev = port->sep_lun->lun_se_dev;
2032 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
2033 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2034 	unsigned char buf[TG_PT_GROUP_NAME_BUF];
2035 	int move = 0;
2036 
2037 	tpg = port->sep_tpg;
2038 	lun = port->sep_lun;
2039 
2040 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
2041 	if (!tg_pt_gp_mem)
2042 		return 0;
2043 
2044 	if (count > TG_PT_GROUP_NAME_BUF) {
2045 		pr_err("ALUA Target Port Group alias too large!\n");
2046 		return -EINVAL;
2047 	}
2048 	memset(buf, 0, TG_PT_GROUP_NAME_BUF);
2049 	memcpy(buf, page, count);
2050 	/*
2051 	 * Any ALUA target port group alias besides "NULL" means we will be
2052 	 * making a new group association.
2053 	 */
2054 	if (strcmp(strstrip(buf), "NULL")) {
2055 		/*
2056 		 * core_alua_get_tg_pt_gp_by_name() will increment reference to
2057 		 * struct t10_alua_tg_pt_gp.  This reference is released with
2058 		 * core_alua_put_tg_pt_gp_from_name() below.
2059 		 */
2060 		tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
2061 					strstrip(buf));
2062 		if (!tg_pt_gp_new)
2063 			return -ENODEV;
2064 	}
2065 
2066 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2067 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
2068 	if (tg_pt_gp) {
2069 		/*
2070 		 * Clearing an existing tg_pt_gp association, and replacing
2071 		 * with the default_tg_pt_gp.
2072 		 */
2073 		if (!tg_pt_gp_new) {
2074 			pr_debug("Target_Core_ConfigFS: Moving"
2075 				" %s/tpgt_%hu/%s from ALUA Target Port Group:"
2076 				" alua/%s, ID: %hu back to"
2077 				" default_tg_pt_gp\n",
2078 				tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2079 				tpg->se_tpg_tfo->tpg_get_tag(tpg),
2080 				config_item_name(&lun->lun_group.cg_item),
2081 				config_item_name(
2082 					&tg_pt_gp->tg_pt_gp_group.cg_item),
2083 				tg_pt_gp->tg_pt_gp_id);
2084 
2085 			__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2086 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
2087 					dev->t10_alua.default_tg_pt_gp);
2088 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2089 
2090 			return count;
2091 		}
2092 		/*
2093 		 * Removing existing association of tg_pt_gp_mem with tg_pt_gp
2094 		 */
2095 		__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2096 		move = 1;
2097 	}
2098 	/*
2099 	 * Associate tg_pt_gp_mem with tg_pt_gp_new.
2100 	 */
2101 	__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
2102 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2103 	pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2104 		" Target Port Group: alua/%s, ID: %hu\n", (move) ?
2105 		"Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2106 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
2107 		config_item_name(&lun->lun_group.cg_item),
2108 		config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2109 		tg_pt_gp_new->tg_pt_gp_id);
2110 
2111 	core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2112 	return count;
2113 }
2114 
2115 ssize_t core_alua_show_access_type(
2116 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2117 	char *page)
2118 {
2119 	if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2120 	    (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2121 		return sprintf(page, "Implicit and Explicit\n");
2122 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2123 		return sprintf(page, "Implicit\n");
2124 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2125 		return sprintf(page, "Explicit\n");
2126 	else
2127 		return sprintf(page, "None\n");
2128 }
2129 
2130 ssize_t core_alua_store_access_type(
2131 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2132 	const char *page,
2133 	size_t count)
2134 {
2135 	unsigned long tmp;
2136 	int ret;
2137 
2138 	ret = kstrtoul(page, 0, &tmp);
2139 	if (ret < 0) {
2140 		pr_err("Unable to extract alua_access_type\n");
2141 		return ret;
2142 	}
2143 	if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2144 		pr_err("Illegal value for alua_access_type:"
2145 				" %lu\n", tmp);
2146 		return -EINVAL;
2147 	}
2148 	if (tmp == 3)
2149 		tg_pt_gp->tg_pt_gp_alua_access_type =
2150 			TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2151 	else if (tmp == 2)
2152 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2153 	else if (tmp == 1)
2154 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2155 	else
2156 		tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2157 
2158 	return count;
2159 }
2160 
2161 ssize_t core_alua_show_nonop_delay_msecs(
2162 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2163 	char *page)
2164 {
2165 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2166 }
2167 
2168 ssize_t core_alua_store_nonop_delay_msecs(
2169 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2170 	const char *page,
2171 	size_t count)
2172 {
2173 	unsigned long tmp;
2174 	int ret;
2175 
2176 	ret = kstrtoul(page, 0, &tmp);
2177 	if (ret < 0) {
2178 		pr_err("Unable to extract nonop_delay_msecs\n");
2179 		return ret;
2180 	}
2181 	if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2182 		pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2183 			" ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2184 			ALUA_MAX_NONOP_DELAY_MSECS);
2185 		return -EINVAL;
2186 	}
2187 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2188 
2189 	return count;
2190 }
2191 
2192 ssize_t core_alua_show_trans_delay_msecs(
2193 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2194 	char *page)
2195 {
2196 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2197 }
2198 
2199 ssize_t core_alua_store_trans_delay_msecs(
2200 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2201 	const char *page,
2202 	size_t count)
2203 {
2204 	unsigned long tmp;
2205 	int ret;
2206 
2207 	ret = kstrtoul(page, 0, &tmp);
2208 	if (ret < 0) {
2209 		pr_err("Unable to extract trans_delay_msecs\n");
2210 		return ret;
2211 	}
2212 	if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2213 		pr_err("Passed trans_delay_msecs: %lu, exceeds"
2214 			" ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2215 			ALUA_MAX_TRANS_DELAY_MSECS);
2216 		return -EINVAL;
2217 	}
2218 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2219 
2220 	return count;
2221 }
2222 
2223 ssize_t core_alua_show_implicit_trans_secs(
2224 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2225 	char *page)
2226 {
2227 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2228 }
2229 
2230 ssize_t core_alua_store_implicit_trans_secs(
2231 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2232 	const char *page,
2233 	size_t count)
2234 {
2235 	unsigned long tmp;
2236 	int ret;
2237 
2238 	ret = kstrtoul(page, 0, &tmp);
2239 	if (ret < 0) {
2240 		pr_err("Unable to extract implicit_trans_secs\n");
2241 		return ret;
2242 	}
2243 	if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2244 		pr_err("Passed implicit_trans_secs: %lu, exceeds"
2245 			" ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2246 			ALUA_MAX_IMPLICIT_TRANS_SECS);
2247 		return  -EINVAL;
2248 	}
2249 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2250 
2251 	return count;
2252 }
2253 
2254 ssize_t core_alua_show_preferred_bit(
2255 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2256 	char *page)
2257 {
2258 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2259 }
2260 
2261 ssize_t core_alua_store_preferred_bit(
2262 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2263 	const char *page,
2264 	size_t count)
2265 {
2266 	unsigned long tmp;
2267 	int ret;
2268 
2269 	ret = kstrtoul(page, 0, &tmp);
2270 	if (ret < 0) {
2271 		pr_err("Unable to extract preferred ALUA value\n");
2272 		return ret;
2273 	}
2274 	if ((tmp != 0) && (tmp != 1)) {
2275 		pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2276 		return -EINVAL;
2277 	}
2278 	tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2279 
2280 	return count;
2281 }
2282 
2283 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2284 {
2285 	if (!lun->lun_sep)
2286 		return -ENODEV;
2287 
2288 	return sprintf(page, "%d\n",
2289 		atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
2290 }
2291 
2292 ssize_t core_alua_store_offline_bit(
2293 	struct se_lun *lun,
2294 	const char *page,
2295 	size_t count)
2296 {
2297 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2298 	unsigned long tmp;
2299 	int ret;
2300 
2301 	if (!lun->lun_sep)
2302 		return -ENODEV;
2303 
2304 	ret = kstrtoul(page, 0, &tmp);
2305 	if (ret < 0) {
2306 		pr_err("Unable to extract alua_tg_pt_offline value\n");
2307 		return ret;
2308 	}
2309 	if ((tmp != 0) && (tmp != 1)) {
2310 		pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2311 				tmp);
2312 		return -EINVAL;
2313 	}
2314 	tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
2315 	if (!tg_pt_gp_mem) {
2316 		pr_err("Unable to locate *tg_pt_gp_mem\n");
2317 		return -EINVAL;
2318 	}
2319 
2320 	ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
2321 			lun->lun_sep, 0, (int)tmp);
2322 	if (ret < 0)
2323 		return -EINVAL;
2324 
2325 	return count;
2326 }
2327 
2328 ssize_t core_alua_show_secondary_status(
2329 	struct se_lun *lun,
2330 	char *page)
2331 {
2332 	return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
2333 }
2334 
2335 ssize_t core_alua_store_secondary_status(
2336 	struct se_lun *lun,
2337 	const char *page,
2338 	size_t count)
2339 {
2340 	unsigned long tmp;
2341 	int ret;
2342 
2343 	ret = kstrtoul(page, 0, &tmp);
2344 	if (ret < 0) {
2345 		pr_err("Unable to extract alua_tg_pt_status\n");
2346 		return ret;
2347 	}
2348 	if ((tmp != ALUA_STATUS_NONE) &&
2349 	    (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2350 	    (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2351 		pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2352 				tmp);
2353 		return -EINVAL;
2354 	}
2355 	lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
2356 
2357 	return count;
2358 }
2359 
2360 ssize_t core_alua_show_secondary_write_metadata(
2361 	struct se_lun *lun,
2362 	char *page)
2363 {
2364 	return sprintf(page, "%d\n",
2365 			lun->lun_sep->sep_tg_pt_secondary_write_md);
2366 }
2367 
2368 ssize_t core_alua_store_secondary_write_metadata(
2369 	struct se_lun *lun,
2370 	const char *page,
2371 	size_t count)
2372 {
2373 	unsigned long tmp;
2374 	int ret;
2375 
2376 	ret = kstrtoul(page, 0, &tmp);
2377 	if (ret < 0) {
2378 		pr_err("Unable to extract alua_tg_pt_write_md\n");
2379 		return ret;
2380 	}
2381 	if ((tmp != 0) && (tmp != 1)) {
2382 		pr_err("Illegal value for alua_tg_pt_write_md:"
2383 				" %lu\n", tmp);
2384 		return -EINVAL;
2385 	}
2386 	lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
2387 
2388 	return count;
2389 }
2390 
2391 int core_setup_alua(struct se_device *dev)
2392 {
2393 	if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV &&
2394 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2395 		struct t10_alua_lu_gp_member *lu_gp_mem;
2396 
2397 		/*
2398 		 * Associate this struct se_device with the default ALUA
2399 		 * LUN Group.
2400 		 */
2401 		lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2402 		if (IS_ERR(lu_gp_mem))
2403 			return PTR_ERR(lu_gp_mem);
2404 
2405 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2406 		__core_alua_attach_lu_gp_mem(lu_gp_mem,
2407 				default_lu_gp);
2408 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2409 
2410 		pr_debug("%s: Adding to default ALUA LU Group:"
2411 			" core/alua/lu_gps/default_lu_gp\n",
2412 			dev->transport->name);
2413 	}
2414 
2415 	return 0;
2416 }
2417