xref: /linux/drivers/target/target_core_alua.c (revision 3e44c471a2dab210f7e9b1e5f7d4d54d52df59eb)
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_proto.h>
32 #include <asm/unaligned.h>
33 
34 #include <target/target_core_base.h>
35 #include <target/target_core_backend.h>
36 #include <target/target_core_fabric.h>
37 #include <target/target_core_configfs.h>
38 
39 #include "target_core_internal.h"
40 #include "target_core_alua.h"
41 #include "target_core_ua.h"
42 
43 static sense_reason_t core_alua_check_transition(int state, int valid,
44 						 int *primary);
45 static int core_alua_set_tg_pt_secondary_state(
46 		struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
47 		struct se_port *port, int explicit, int offline);
48 
49 static char *core_alua_dump_state(int state);
50 
51 static u16 alua_lu_gps_counter;
52 static u32 alua_lu_gps_count;
53 
54 static DEFINE_SPINLOCK(lu_gps_lock);
55 static LIST_HEAD(lu_gps_list);
56 
57 struct t10_alua_lu_gp *default_lu_gp;
58 
59 /*
60  * REPORT REFERRALS
61  *
62  * See sbc3r35 section 5.23
63  */
64 sense_reason_t
65 target_emulate_report_referrals(struct se_cmd *cmd)
66 {
67 	struct se_device *dev = cmd->se_dev;
68 	struct t10_alua_lba_map *map;
69 	struct t10_alua_lba_map_member *map_mem;
70 	unsigned char *buf;
71 	u32 rd_len = 0, off;
72 
73 	if (cmd->data_length < 4) {
74 		pr_warn("REPORT REFERRALS allocation length %u too"
75 			" small\n", cmd->data_length);
76 		return TCM_INVALID_CDB_FIELD;
77 	}
78 
79 	buf = transport_kmap_data_sg(cmd);
80 	if (!buf)
81 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
82 
83 	off = 4;
84 	spin_lock(&dev->t10_alua.lba_map_lock);
85 	if (list_empty(&dev->t10_alua.lba_map_list)) {
86 		spin_unlock(&dev->t10_alua.lba_map_lock);
87 		transport_kunmap_data_sg(cmd);
88 
89 		return TCM_UNSUPPORTED_SCSI_OPCODE;
90 	}
91 
92 	list_for_each_entry(map, &dev->t10_alua.lba_map_list,
93 			    lba_map_list) {
94 		int desc_num = off + 3;
95 		int pg_num;
96 
97 		off += 4;
98 		if (cmd->data_length > off)
99 			put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
100 		off += 8;
101 		if (cmd->data_length > off)
102 			put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
103 		off += 8;
104 		rd_len += 20;
105 		pg_num = 0;
106 		list_for_each_entry(map_mem, &map->lba_map_mem_list,
107 				    lba_map_mem_list) {
108 			int alua_state = map_mem->lba_map_mem_alua_state;
109 			int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
110 
111 			if (cmd->data_length > off)
112 				buf[off] = alua_state & 0x0f;
113 			off += 2;
114 			if (cmd->data_length > off)
115 				buf[off] = (alua_pg_id >> 8) & 0xff;
116 			off++;
117 			if (cmd->data_length > off)
118 				buf[off] = (alua_pg_id & 0xff);
119 			off++;
120 			rd_len += 4;
121 			pg_num++;
122 		}
123 		if (cmd->data_length > desc_num)
124 			buf[desc_num] = pg_num;
125 	}
126 	spin_unlock(&dev->t10_alua.lba_map_lock);
127 
128 	/*
129 	 * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
130 	 */
131 	put_unaligned_be16(rd_len, &buf[2]);
132 
133 	transport_kunmap_data_sg(cmd);
134 
135 	target_complete_cmd(cmd, GOOD);
136 	return 0;
137 }
138 
139 /*
140  * REPORT_TARGET_PORT_GROUPS
141  *
142  * See spc4r17 section 6.27
143  */
144 sense_reason_t
145 target_emulate_report_target_port_groups(struct se_cmd *cmd)
146 {
147 	struct se_device *dev = cmd->se_dev;
148 	struct se_port *port;
149 	struct t10_alua_tg_pt_gp *tg_pt_gp;
150 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
151 	unsigned char *buf;
152 	u32 rd_len = 0, off;
153 	int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
154 
155 	/*
156 	 * Skip over RESERVED area to first Target port group descriptor
157 	 * depending on the PARAMETER DATA FORMAT type..
158 	 */
159 	if (ext_hdr != 0)
160 		off = 8;
161 	else
162 		off = 4;
163 
164 	if (cmd->data_length < off) {
165 		pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
166 			" small for %s header\n", cmd->data_length,
167 			(ext_hdr) ? "extended" : "normal");
168 		return TCM_INVALID_CDB_FIELD;
169 	}
170 	buf = transport_kmap_data_sg(cmd);
171 	if (!buf)
172 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
173 
174 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
175 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
176 			tg_pt_gp_list) {
177 		/*
178 		 * Check if the Target port group and Target port descriptor list
179 		 * based on tg_pt_gp_members count will fit into the response payload.
180 		 * Otherwise, bump rd_len to let the initiator know we have exceeded
181 		 * the allocation length and the response is truncated.
182 		 */
183 		if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
184 		     cmd->data_length) {
185 			rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
186 			continue;
187 		}
188 		/*
189 		 * PREF: Preferred target port bit, determine if this
190 		 * bit should be set for port group.
191 		 */
192 		if (tg_pt_gp->tg_pt_gp_pref)
193 			buf[off] = 0x80;
194 		/*
195 		 * Set the ASYMMETRIC ACCESS State
196 		 */
197 		buf[off++] |= (atomic_read(
198 			&tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
199 		/*
200 		 * Set supported ASYMMETRIC ACCESS State bits
201 		 */
202 		buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
203 		/*
204 		 * TARGET PORT GROUP
205 		 */
206 		buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
207 		buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
208 
209 		off++; /* Skip over Reserved */
210 		/*
211 		 * STATUS CODE
212 		 */
213 		buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
214 		/*
215 		 * Vendor Specific field
216 		 */
217 		buf[off++] = 0x00;
218 		/*
219 		 * TARGET PORT COUNT
220 		 */
221 		buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
222 		rd_len += 8;
223 
224 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
225 		list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
226 				tg_pt_gp_mem_list) {
227 			port = tg_pt_gp_mem->tg_pt;
228 			/*
229 			 * Start Target Port descriptor format
230 			 *
231 			 * See spc4r17 section 6.2.7 Table 247
232 			 */
233 			off += 2; /* Skip over Obsolete */
234 			/*
235 			 * Set RELATIVE TARGET PORT IDENTIFIER
236 			 */
237 			buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
238 			buf[off++] = (port->sep_rtpi & 0xff);
239 			rd_len += 4;
240 		}
241 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
242 	}
243 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
244 	/*
245 	 * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
246 	 */
247 	put_unaligned_be32(rd_len, &buf[0]);
248 
249 	/*
250 	 * Fill in the Extended header parameter data format if requested
251 	 */
252 	if (ext_hdr != 0) {
253 		buf[4] = 0x10;
254 		/*
255 		 * Set the implicit transition time (in seconds) for the application
256 		 * client to use as a base for it's transition timeout value.
257 		 *
258 		 * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
259 		 * this CDB was received upon to determine this value individually
260 		 * for ALUA target port group.
261 		 */
262 		port = cmd->se_lun->lun_sep;
263 		tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
264 		if (tg_pt_gp_mem) {
265 			spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
266 			tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
267 			if (tg_pt_gp)
268 				buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
269 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
270 		}
271 	}
272 	transport_kunmap_data_sg(cmd);
273 
274 	target_complete_cmd(cmd, GOOD);
275 	return 0;
276 }
277 
278 /*
279  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
280  *
281  * See spc4r17 section 6.35
282  */
283 sense_reason_t
284 target_emulate_set_target_port_groups(struct se_cmd *cmd)
285 {
286 	struct se_device *dev = cmd->se_dev;
287 	struct se_port *port, *l_port = cmd->se_lun->lun_sep;
288 	struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
289 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
290 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
291 	unsigned char *buf;
292 	unsigned char *ptr;
293 	sense_reason_t rc = TCM_NO_SENSE;
294 	u32 len = 4; /* Skip over RESERVED area in header */
295 	int alua_access_state, primary = 0, valid_states;
296 	u16 tg_pt_id, rtpi;
297 
298 	if (!l_port)
299 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
300 
301 	if (cmd->data_length < 4) {
302 		pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
303 			" small\n", cmd->data_length);
304 		return TCM_INVALID_PARAMETER_LIST;
305 	}
306 
307 	buf = transport_kmap_data_sg(cmd);
308 	if (!buf)
309 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
310 
311 	/*
312 	 * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
313 	 * for the local tg_pt_gp.
314 	 */
315 	l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
316 	if (!l_tg_pt_gp_mem) {
317 		pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
318 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
319 		goto out;
320 	}
321 	spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
322 	l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
323 	if (!l_tg_pt_gp) {
324 		spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
325 		pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
326 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
327 		goto out;
328 	}
329 	spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
330 
331 	if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
332 		pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
333 				" while TPGS_EXPLICIT_ALUA is disabled\n");
334 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
335 		goto out;
336 	}
337 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
338 
339 	ptr = &buf[4]; /* Skip over RESERVED area in header */
340 
341 	while (len < cmd->data_length) {
342 		bool found = false;
343 		alua_access_state = (ptr[0] & 0x0f);
344 		/*
345 		 * Check the received ALUA access state, and determine if
346 		 * the state is a primary or secondary target port asymmetric
347 		 * access state.
348 		 */
349 		rc = core_alua_check_transition(alua_access_state,
350 						valid_states, &primary);
351 		if (rc) {
352 			/*
353 			 * If the SET TARGET PORT GROUPS attempts to establish
354 			 * an invalid combination of target port asymmetric
355 			 * access states or attempts to establish an
356 			 * unsupported target port asymmetric access state,
357 			 * then the command shall be terminated with CHECK
358 			 * CONDITION status, with the sense key set to ILLEGAL
359 			 * REQUEST, and the additional sense code set to INVALID
360 			 * FIELD IN PARAMETER LIST.
361 			 */
362 			goto out;
363 		}
364 
365 		/*
366 		 * If the ASYMMETRIC ACCESS STATE field (see table 267)
367 		 * specifies a primary target port asymmetric access state,
368 		 * then the TARGET PORT GROUP OR TARGET PORT field specifies
369 		 * a primary target port group for which the primary target
370 		 * port asymmetric access state shall be changed. If the
371 		 * ASYMMETRIC ACCESS STATE field specifies a secondary target
372 		 * port asymmetric access state, then the TARGET PORT GROUP OR
373 		 * TARGET PORT field specifies the relative target port
374 		 * identifier (see 3.1.120) of the target port for which the
375 		 * secondary target port asymmetric access state shall be
376 		 * changed.
377 		 */
378 		if (primary) {
379 			tg_pt_id = get_unaligned_be16(ptr + 2);
380 			/*
381 			 * Locate the matching target port group ID from
382 			 * the global tg_pt_gp list
383 			 */
384 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
385 			list_for_each_entry(tg_pt_gp,
386 					&dev->t10_alua.tg_pt_gps_list,
387 					tg_pt_gp_list) {
388 				if (!tg_pt_gp->tg_pt_gp_valid_id)
389 					continue;
390 
391 				if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
392 					continue;
393 
394 				atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
395 
396 				spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
397 
398 				if (!core_alua_do_port_transition(tg_pt_gp,
399 						dev, l_port, nacl,
400 						alua_access_state, 1))
401 					found = true;
402 
403 				spin_lock(&dev->t10_alua.tg_pt_gps_lock);
404 				atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
405 				break;
406 			}
407 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
408 		} else {
409 			/*
410 			 * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
411 			 * the Target Port in question for the the incoming
412 			 * SET_TARGET_PORT_GROUPS op.
413 			 */
414 			rtpi = get_unaligned_be16(ptr + 2);
415 			/*
416 			 * Locate the matching relative target port identifier
417 			 * for the struct se_device storage object.
418 			 */
419 			spin_lock(&dev->se_port_lock);
420 			list_for_each_entry(port, &dev->dev_sep_list,
421 							sep_list) {
422 				if (port->sep_rtpi != rtpi)
423 					continue;
424 
425 				tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
426 
427 				spin_unlock(&dev->se_port_lock);
428 
429 				if (!core_alua_set_tg_pt_secondary_state(
430 						tg_pt_gp_mem, port, 1, 1))
431 					found = true;
432 
433 				spin_lock(&dev->se_port_lock);
434 				break;
435 			}
436 			spin_unlock(&dev->se_port_lock);
437 		}
438 
439 		if (!found) {
440 			rc = TCM_INVALID_PARAMETER_LIST;
441 			goto out;
442 		}
443 
444 		ptr += 4;
445 		len += 4;
446 	}
447 
448 out:
449 	transport_kunmap_data_sg(cmd);
450 	if (!rc)
451 		target_complete_cmd(cmd, GOOD);
452 	return rc;
453 }
454 
455 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
456 {
457 	/*
458 	 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
459 	 * The ALUA additional sense code qualifier (ASCQ) is determined
460 	 * by the ALUA primary or secondary access state..
461 	 */
462 	pr_debug("[%s]: ALUA TG Port not available, "
463 		"SenseKey: NOT_READY, ASC/ASCQ: "
464 		"0x04/0x%02x\n",
465 		cmd->se_tfo->get_fabric_name(), alua_ascq);
466 
467 	cmd->scsi_asc = 0x04;
468 	cmd->scsi_ascq = alua_ascq;
469 }
470 
471 static inline void core_alua_state_nonoptimized(
472 	struct se_cmd *cmd,
473 	unsigned char *cdb,
474 	int nonop_delay_msecs)
475 {
476 	/*
477 	 * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
478 	 * later to determine if processing of this cmd needs to be
479 	 * temporarily delayed for the Active/NonOptimized primary access state.
480 	 */
481 	cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
482 	cmd->alua_nonop_delay = nonop_delay_msecs;
483 }
484 
485 static inline int core_alua_state_lba_dependent(
486 	struct se_cmd *cmd,
487 	struct t10_alua_tg_pt_gp *tg_pt_gp)
488 {
489 	struct se_device *dev = cmd->se_dev;
490 	u64 segment_size, segment_mult, sectors, lba;
491 
492 	/* Only need to check for cdb actually containing LBAs */
493 	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
494 		return 0;
495 
496 	spin_lock(&dev->t10_alua.lba_map_lock);
497 	segment_size = dev->t10_alua.lba_map_segment_size;
498 	segment_mult = dev->t10_alua.lba_map_segment_multiplier;
499 	sectors = cmd->data_length / dev->dev_attrib.block_size;
500 
501 	lba = cmd->t_task_lba;
502 	while (lba < cmd->t_task_lba + sectors) {
503 		struct t10_alua_lba_map *cur_map = NULL, *map;
504 		struct t10_alua_lba_map_member *map_mem;
505 
506 		list_for_each_entry(map, &dev->t10_alua.lba_map_list,
507 				    lba_map_list) {
508 			u64 start_lba, last_lba;
509 			u64 first_lba = map->lba_map_first_lba;
510 
511 			if (segment_mult) {
512 				u64 tmp = lba;
513 				start_lba = do_div(tmp, segment_size * segment_mult);
514 
515 				last_lba = first_lba + segment_size - 1;
516 				if (start_lba >= first_lba &&
517 				    start_lba <= last_lba) {
518 					lba += segment_size;
519 					cur_map = map;
520 					break;
521 				}
522 			} else {
523 				last_lba = map->lba_map_last_lba;
524 				if (lba >= first_lba && lba <= last_lba) {
525 					lba = last_lba + 1;
526 					cur_map = map;
527 					break;
528 				}
529 			}
530 		}
531 		if (!cur_map) {
532 			spin_unlock(&dev->t10_alua.lba_map_lock);
533 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
534 			return 1;
535 		}
536 		list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
537 				    lba_map_mem_list) {
538 			if (map_mem->lba_map_mem_alua_pg_id !=
539 			    tg_pt_gp->tg_pt_gp_id)
540 				continue;
541 			switch(map_mem->lba_map_mem_alua_state) {
542 			case ALUA_ACCESS_STATE_STANDBY:
543 				spin_unlock(&dev->t10_alua.lba_map_lock);
544 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
545 				return 1;
546 			case ALUA_ACCESS_STATE_UNAVAILABLE:
547 				spin_unlock(&dev->t10_alua.lba_map_lock);
548 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
549 				return 1;
550 			default:
551 				break;
552 			}
553 		}
554 	}
555 	spin_unlock(&dev->t10_alua.lba_map_lock);
556 	return 0;
557 }
558 
559 static inline int core_alua_state_standby(
560 	struct se_cmd *cmd,
561 	unsigned char *cdb)
562 {
563 	/*
564 	 * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
565 	 * spc4r17 section 5.9.2.4.4
566 	 */
567 	switch (cdb[0]) {
568 	case INQUIRY:
569 	case LOG_SELECT:
570 	case LOG_SENSE:
571 	case MODE_SELECT:
572 	case MODE_SENSE:
573 	case REPORT_LUNS:
574 	case RECEIVE_DIAGNOSTIC:
575 	case SEND_DIAGNOSTIC:
576 	case READ_CAPACITY:
577 		return 0;
578 	case SERVICE_ACTION_IN_16:
579 		switch (cdb[1] & 0x1f) {
580 		case SAI_READ_CAPACITY_16:
581 			return 0;
582 		default:
583 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
584 			return 1;
585 		}
586 	case MAINTENANCE_IN:
587 		switch (cdb[1] & 0x1f) {
588 		case MI_REPORT_TARGET_PGS:
589 			return 0;
590 		default:
591 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
592 			return 1;
593 		}
594 	case MAINTENANCE_OUT:
595 		switch (cdb[1]) {
596 		case MO_SET_TARGET_PGS:
597 			return 0;
598 		default:
599 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
600 			return 1;
601 		}
602 	case REQUEST_SENSE:
603 	case PERSISTENT_RESERVE_IN:
604 	case PERSISTENT_RESERVE_OUT:
605 	case READ_BUFFER:
606 	case WRITE_BUFFER:
607 		return 0;
608 	default:
609 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
610 		return 1;
611 	}
612 
613 	return 0;
614 }
615 
616 static inline int core_alua_state_unavailable(
617 	struct se_cmd *cmd,
618 	unsigned char *cdb)
619 {
620 	/*
621 	 * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
622 	 * spc4r17 section 5.9.2.4.5
623 	 */
624 	switch (cdb[0]) {
625 	case INQUIRY:
626 	case REPORT_LUNS:
627 		return 0;
628 	case MAINTENANCE_IN:
629 		switch (cdb[1] & 0x1f) {
630 		case MI_REPORT_TARGET_PGS:
631 			return 0;
632 		default:
633 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
634 			return 1;
635 		}
636 	case MAINTENANCE_OUT:
637 		switch (cdb[1]) {
638 		case MO_SET_TARGET_PGS:
639 			return 0;
640 		default:
641 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
642 			return 1;
643 		}
644 	case REQUEST_SENSE:
645 	case READ_BUFFER:
646 	case WRITE_BUFFER:
647 		return 0;
648 	default:
649 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
650 		return 1;
651 	}
652 
653 	return 0;
654 }
655 
656 static inline int core_alua_state_transition(
657 	struct se_cmd *cmd,
658 	unsigned char *cdb)
659 {
660 	/*
661 	 * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
662 	 * spc4r17 section 5.9.2.5
663 	 */
664 	switch (cdb[0]) {
665 	case INQUIRY:
666 	case REPORT_LUNS:
667 		return 0;
668 	case MAINTENANCE_IN:
669 		switch (cdb[1] & 0x1f) {
670 		case MI_REPORT_TARGET_PGS:
671 			return 0;
672 		default:
673 			set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
674 			return 1;
675 		}
676 	case REQUEST_SENSE:
677 	case READ_BUFFER:
678 	case WRITE_BUFFER:
679 		return 0;
680 	default:
681 		set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
682 		return 1;
683 	}
684 
685 	return 0;
686 }
687 
688 /*
689  * return 1: Is used to signal LUN not accessible, and check condition/not ready
690  * return 0: Used to signal success
691  * return -1: Used to signal failure, and invalid cdb field
692  */
693 sense_reason_t
694 target_alua_state_check(struct se_cmd *cmd)
695 {
696 	struct se_device *dev = cmd->se_dev;
697 	unsigned char *cdb = cmd->t_task_cdb;
698 	struct se_lun *lun = cmd->se_lun;
699 	struct se_port *port = lun->lun_sep;
700 	struct t10_alua_tg_pt_gp *tg_pt_gp;
701 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
702 	int out_alua_state, nonop_delay_msecs;
703 
704 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
705 		return 0;
706 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
707 		return 0;
708 
709 	if (!port)
710 		return 0;
711 	/*
712 	 * First, check for a struct se_port specific secondary ALUA target port
713 	 * access state: OFFLINE
714 	 */
715 	if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
716 		pr_debug("ALUA: Got secondary offline status for local"
717 				" target port\n");
718 		set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
719 		return TCM_CHECK_CONDITION_NOT_READY;
720 	}
721 	 /*
722 	 * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
723 	 * ALUA target port group, to obtain current ALUA access state.
724 	 * Otherwise look for the underlying struct se_device association with
725 	 * a ALUA logical unit group.
726 	 */
727 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
728 	if (!tg_pt_gp_mem)
729 		return 0;
730 
731 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
732 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
733 	out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
734 	nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
735 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
736 	/*
737 	 * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
738 	 * statement so the compiler knows explicitly to check this case first.
739 	 * For the Optimized ALUA access state case, we want to process the
740 	 * incoming fabric cmd ASAP..
741 	 */
742 	if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
743 		return 0;
744 
745 	switch (out_alua_state) {
746 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
747 		core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
748 		break;
749 	case ALUA_ACCESS_STATE_STANDBY:
750 		if (core_alua_state_standby(cmd, cdb))
751 			return TCM_CHECK_CONDITION_NOT_READY;
752 		break;
753 	case ALUA_ACCESS_STATE_UNAVAILABLE:
754 		if (core_alua_state_unavailable(cmd, cdb))
755 			return TCM_CHECK_CONDITION_NOT_READY;
756 		break;
757 	case ALUA_ACCESS_STATE_TRANSITION:
758 		if (core_alua_state_transition(cmd, cdb))
759 			return TCM_CHECK_CONDITION_NOT_READY;
760 		break;
761 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
762 		if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
763 			return TCM_CHECK_CONDITION_NOT_READY;
764 		break;
765 	/*
766 	 * OFFLINE is a secondary ALUA target port group access state, that is
767 	 * handled above with struct se_port->sep_tg_pt_secondary_offline=1
768 	 */
769 	case ALUA_ACCESS_STATE_OFFLINE:
770 	default:
771 		pr_err("Unknown ALUA access state: 0x%02x\n",
772 				out_alua_state);
773 		return TCM_INVALID_CDB_FIELD;
774 	}
775 
776 	return 0;
777 }
778 
779 /*
780  * Check implicit and explicit ALUA state change request.
781  */
782 static sense_reason_t
783 core_alua_check_transition(int state, int valid, int *primary)
784 {
785 	/*
786 	 * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
787 	 * defined as primary target port asymmetric access states.
788 	 */
789 	switch (state) {
790 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
791 		if (!(valid & ALUA_AO_SUP))
792 			goto not_supported;
793 		*primary = 1;
794 		break;
795 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
796 		if (!(valid & ALUA_AN_SUP))
797 			goto not_supported;
798 		*primary = 1;
799 		break;
800 	case ALUA_ACCESS_STATE_STANDBY:
801 		if (!(valid & ALUA_S_SUP))
802 			goto not_supported;
803 		*primary = 1;
804 		break;
805 	case ALUA_ACCESS_STATE_UNAVAILABLE:
806 		if (!(valid & ALUA_U_SUP))
807 			goto not_supported;
808 		*primary = 1;
809 		break;
810 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
811 		if (!(valid & ALUA_LBD_SUP))
812 			goto not_supported;
813 		*primary = 1;
814 		break;
815 	case ALUA_ACCESS_STATE_OFFLINE:
816 		/*
817 		 * OFFLINE state is defined as a secondary target port
818 		 * asymmetric access state.
819 		 */
820 		if (!(valid & ALUA_O_SUP))
821 			goto not_supported;
822 		*primary = 0;
823 		break;
824 	case ALUA_ACCESS_STATE_TRANSITION:
825 		/*
826 		 * Transitioning is set internally, and
827 		 * cannot be selected manually.
828 		 */
829 		goto not_supported;
830 	default:
831 		pr_err("Unknown ALUA access state: 0x%02x\n", state);
832 		return TCM_INVALID_PARAMETER_LIST;
833 	}
834 
835 	return 0;
836 
837 not_supported:
838 	pr_err("ALUA access state %s not supported",
839 	       core_alua_dump_state(state));
840 	return TCM_INVALID_PARAMETER_LIST;
841 }
842 
843 static char *core_alua_dump_state(int state)
844 {
845 	switch (state) {
846 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
847 		return "Active/Optimized";
848 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
849 		return "Active/NonOptimized";
850 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
851 		return "LBA Dependent";
852 	case ALUA_ACCESS_STATE_STANDBY:
853 		return "Standby";
854 	case ALUA_ACCESS_STATE_UNAVAILABLE:
855 		return "Unavailable";
856 	case ALUA_ACCESS_STATE_OFFLINE:
857 		return "Offline";
858 	case ALUA_ACCESS_STATE_TRANSITION:
859 		return "Transitioning";
860 	default:
861 		return "Unknown";
862 	}
863 
864 	return NULL;
865 }
866 
867 char *core_alua_dump_status(int status)
868 {
869 	switch (status) {
870 	case ALUA_STATUS_NONE:
871 		return "None";
872 	case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
873 		return "Altered by Explicit STPG";
874 	case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
875 		return "Altered by Implicit ALUA";
876 	default:
877 		return "Unknown";
878 	}
879 
880 	return NULL;
881 }
882 
883 /*
884  * Used by fabric modules to determine when we need to delay processing
885  * for the Active/NonOptimized paths..
886  */
887 int core_alua_check_nonop_delay(
888 	struct se_cmd *cmd)
889 {
890 	if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
891 		return 0;
892 	if (in_interrupt())
893 		return 0;
894 	/*
895 	 * The ALUA Active/NonOptimized access state delay can be disabled
896 	 * in via configfs with a value of zero
897 	 */
898 	if (!cmd->alua_nonop_delay)
899 		return 0;
900 	/*
901 	 * struct se_cmd->alua_nonop_delay gets set by a target port group
902 	 * defined interval in core_alua_state_nonoptimized()
903 	 */
904 	msleep_interruptible(cmd->alua_nonop_delay);
905 	return 0;
906 }
907 EXPORT_SYMBOL(core_alua_check_nonop_delay);
908 
909 /*
910  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
911  *
912  */
913 static int core_alua_write_tpg_metadata(
914 	const char *path,
915 	unsigned char *md_buf,
916 	u32 md_buf_len)
917 {
918 	struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
919 	int ret;
920 
921 	if (IS_ERR(file)) {
922 		pr_err("filp_open(%s) for ALUA metadata failed\n", path);
923 		return -ENODEV;
924 	}
925 	ret = kernel_write(file, md_buf, md_buf_len, 0);
926 	if (ret < 0)
927 		pr_err("Error writing ALUA metadata file: %s\n", path);
928 	fput(file);
929 	return (ret < 0) ? -EIO : 0;
930 }
931 
932 /*
933  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
934  */
935 static int core_alua_update_tpg_primary_metadata(
936 	struct t10_alua_tg_pt_gp *tg_pt_gp)
937 {
938 	unsigned char *md_buf;
939 	struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
940 	char path[ALUA_METADATA_PATH_LEN];
941 	int len, rc;
942 
943 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
944 	if (!md_buf) {
945 		pr_err("Unable to allocate buf for ALUA metadata\n");
946 		return -ENOMEM;
947 	}
948 
949 	memset(path, 0, ALUA_METADATA_PATH_LEN);
950 
951 	len = snprintf(md_buf, ALUA_MD_BUF_LEN,
952 			"tg_pt_gp_id=%hu\n"
953 			"alua_access_state=0x%02x\n"
954 			"alua_access_status=0x%02x\n",
955 			tg_pt_gp->tg_pt_gp_id,
956 			tg_pt_gp->tg_pt_gp_alua_pending_state,
957 			tg_pt_gp->tg_pt_gp_alua_access_status);
958 
959 	snprintf(path, ALUA_METADATA_PATH_LEN,
960 		"/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
961 		config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
962 
963 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
964 	kfree(md_buf);
965 	return rc;
966 }
967 
968 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
969 {
970 	struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
971 		struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work.work);
972 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
973 	struct se_dev_entry *se_deve;
974 	struct se_lun_acl *lacl;
975 	struct se_port *port;
976 	struct t10_alua_tg_pt_gp_member *mem;
977 	bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
978 			 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
979 
980 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
981 	list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
982 				tg_pt_gp_mem_list) {
983 		port = mem->tg_pt;
984 		/*
985 		 * After an implicit target port asymmetric access state
986 		 * change, a device server shall establish a unit attention
987 		 * condition for the initiator port associated with every I_T
988 		 * nexus with the additional sense code set to ASYMMETRIC
989 		 * ACCESS STATE CHANGED.
990 		 *
991 		 * After an explicit target port asymmetric access state
992 		 * change, a device server shall establish a unit attention
993 		 * condition with the additional sense code set to ASYMMETRIC
994 		 * ACCESS STATE CHANGED for the initiator port associated with
995 		 * every I_T nexus other than the I_T nexus on which the SET
996 		 * TARGET PORT GROUPS command
997 		 */
998 		atomic_inc_mb(&mem->tg_pt_gp_mem_ref_cnt);
999 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1000 
1001 		spin_lock_bh(&port->sep_alua_lock);
1002 		list_for_each_entry(se_deve, &port->sep_alua_list,
1003 					alua_port_list) {
1004 			lacl = se_deve->se_lun_acl;
1005 			/*
1006 			 * se_deve->se_lun_acl pointer may be NULL for a
1007 			 * entry created without explicit Node+MappedLUN ACLs
1008 			 */
1009 			if (!lacl)
1010 				continue;
1011 
1012 			if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
1013 			     ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
1014 			   (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1015 			    (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl) &&
1016 			   (tg_pt_gp->tg_pt_gp_alua_port != NULL) &&
1017 			    (tg_pt_gp->tg_pt_gp_alua_port == port))
1018 				continue;
1019 
1020 			core_scsi3_ua_allocate(lacl->se_lun_nacl,
1021 				se_deve->mapped_lun, 0x2A,
1022 				ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1023 		}
1024 		spin_unlock_bh(&port->sep_alua_lock);
1025 
1026 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1027 		atomic_dec_mb(&mem->tg_pt_gp_mem_ref_cnt);
1028 	}
1029 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1030 	/*
1031 	 * Update the ALUA metadata buf that has been allocated in
1032 	 * core_alua_do_port_transition(), this metadata will be written
1033 	 * to struct file.
1034 	 *
1035 	 * Note that there is the case where we do not want to update the
1036 	 * metadata when the saved metadata is being parsed in userspace
1037 	 * when setting the existing port access state and access status.
1038 	 *
1039 	 * Also note that the failure to write out the ALUA metadata to
1040 	 * struct file does NOT affect the actual ALUA transition.
1041 	 */
1042 	if (tg_pt_gp->tg_pt_gp_write_metadata) {
1043 		mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1044 		core_alua_update_tpg_primary_metadata(tg_pt_gp);
1045 		mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1046 	}
1047 	/*
1048 	 * Set the current primary ALUA access state to the requested new state
1049 	 */
1050 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1051 		   tg_pt_gp->tg_pt_gp_alua_pending_state);
1052 
1053 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1054 		" from primary access state %s to %s\n", (explicit) ? "explicit" :
1055 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1056 		tg_pt_gp->tg_pt_gp_id,
1057 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1058 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1059 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1060 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1061 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1062 
1063 	if (tg_pt_gp->tg_pt_gp_transition_complete)
1064 		complete(tg_pt_gp->tg_pt_gp_transition_complete);
1065 }
1066 
1067 static int core_alua_do_transition_tg_pt(
1068 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1069 	int new_state,
1070 	int explicit)
1071 {
1072 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1073 	DECLARE_COMPLETION_ONSTACK(wait);
1074 
1075 	/* Nothing to be done here */
1076 	if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1077 		return 0;
1078 
1079 	if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1080 		return -EAGAIN;
1081 
1082 	/*
1083 	 * Flush any pending transitions
1084 	 */
1085 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs &&
1086 	    atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
1087 	    ALUA_ACCESS_STATE_TRANSITION) {
1088 		/* Just in case */
1089 		tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1090 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1091 		flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1092 		wait_for_completion(&wait);
1093 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1094 		return 0;
1095 	}
1096 
1097 	/*
1098 	 * Save the old primary ALUA access state, and set the current state
1099 	 * to ALUA_ACCESS_STATE_TRANSITION.
1100 	 */
1101 	tg_pt_gp->tg_pt_gp_alua_previous_state =
1102 		atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1103 	tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1104 
1105 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1106 			ALUA_ACCESS_STATE_TRANSITION);
1107 	tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1108 				ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1109 				ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1110 
1111 	/*
1112 	 * Check for the optional ALUA primary state transition delay
1113 	 */
1114 	if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1115 		msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1116 
1117 	/*
1118 	 * Take a reference for workqueue item
1119 	 */
1120 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1121 	atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1122 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1123 
1124 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs) {
1125 		unsigned long transition_tmo;
1126 
1127 		transition_tmo = tg_pt_gp->tg_pt_gp_implicit_trans_secs * HZ;
1128 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1129 				   &tg_pt_gp->tg_pt_gp_transition_work,
1130 				   transition_tmo);
1131 	} else {
1132 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1133 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1134 				   &tg_pt_gp->tg_pt_gp_transition_work, 0);
1135 		wait_for_completion(&wait);
1136 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1137 	}
1138 
1139 	return 0;
1140 }
1141 
1142 int core_alua_do_port_transition(
1143 	struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1144 	struct se_device *l_dev,
1145 	struct se_port *l_port,
1146 	struct se_node_acl *l_nacl,
1147 	int new_state,
1148 	int explicit)
1149 {
1150 	struct se_device *dev;
1151 	struct t10_alua_lu_gp *lu_gp;
1152 	struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1153 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1154 	int primary, valid_states, rc = 0;
1155 
1156 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1157 	if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1158 		return -EINVAL;
1159 
1160 	local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1161 	spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1162 	lu_gp = local_lu_gp_mem->lu_gp;
1163 	atomic_inc(&lu_gp->lu_gp_ref_cnt);
1164 	spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1165 	/*
1166 	 * For storage objects that are members of the 'default_lu_gp',
1167 	 * we only do transition on the passed *l_tp_pt_gp, and not
1168 	 * on all of the matching target port groups IDs in default_lu_gp.
1169 	 */
1170 	if (!lu_gp->lu_gp_id) {
1171 		/*
1172 		 * core_alua_do_transition_tg_pt() will always return
1173 		 * success.
1174 		 */
1175 		l_tg_pt_gp->tg_pt_gp_alua_port = l_port;
1176 		l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1177 		rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1178 						   new_state, explicit);
1179 		atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
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_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1193 		spin_unlock(&lu_gp->lu_gp_lock);
1194 
1195 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1196 		list_for_each_entry(tg_pt_gp,
1197 				&dev->t10_alua.tg_pt_gps_list,
1198 				tg_pt_gp_list) {
1199 
1200 			if (!tg_pt_gp->tg_pt_gp_valid_id)
1201 				continue;
1202 			/*
1203 			 * If the target behavior port asymmetric access state
1204 			 * is changed for any target port group accessible via
1205 			 * a logical unit within a LU group, the target port
1206 			 * behavior group asymmetric access states for the same
1207 			 * target port group accessible via other logical units
1208 			 * in that LU group will also change.
1209 			 */
1210 			if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1211 				continue;
1212 
1213 			if (l_tg_pt_gp == tg_pt_gp) {
1214 				tg_pt_gp->tg_pt_gp_alua_port = l_port;
1215 				tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1216 			} else {
1217 				tg_pt_gp->tg_pt_gp_alua_port = NULL;
1218 				tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1219 			}
1220 			atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1221 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1222 			/*
1223 			 * core_alua_do_transition_tg_pt() will always return
1224 			 * success.
1225 			 */
1226 			rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1227 					new_state, explicit);
1228 
1229 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1230 			atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1231 			if (rc)
1232 				break;
1233 		}
1234 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1235 
1236 		spin_lock(&lu_gp->lu_gp_lock);
1237 		atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1238 	}
1239 	spin_unlock(&lu_gp->lu_gp_lock);
1240 
1241 	if (!rc) {
1242 		pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1243 			 " Group IDs: %hu %s transition to primary state: %s\n",
1244 			 config_item_name(&lu_gp->lu_gp_group.cg_item),
1245 			 l_tg_pt_gp->tg_pt_gp_id,
1246 			 (explicit) ? "explicit" : "implicit",
1247 			 core_alua_dump_state(new_state));
1248 	}
1249 
1250 	atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1251 	return rc;
1252 }
1253 
1254 /*
1255  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
1256  */
1257 static int core_alua_update_tpg_secondary_metadata(
1258 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1259 	struct se_port *port)
1260 {
1261 	unsigned char *md_buf;
1262 	struct se_portal_group *se_tpg = port->sep_tpg;
1263 	char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1264 	int len, rc;
1265 
1266 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1267 	if (!md_buf) {
1268 		pr_err("Unable to allocate buf for ALUA metadata\n");
1269 		return -ENOMEM;
1270 	}
1271 
1272 	memset(path, 0, ALUA_METADATA_PATH_LEN);
1273 	memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1274 
1275 	len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1276 			se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1277 
1278 	if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1279 		snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1280 				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1281 
1282 	len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1283 			"alua_tg_pt_status=0x%02x\n",
1284 			atomic_read(&port->sep_tg_pt_secondary_offline),
1285 			port->sep_tg_pt_secondary_stat);
1286 
1287 	snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
1288 			se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1289 			port->sep_lun->unpacked_lun);
1290 
1291 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
1292 	kfree(md_buf);
1293 
1294 	return rc;
1295 }
1296 
1297 static int core_alua_set_tg_pt_secondary_state(
1298 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1299 	struct se_port *port,
1300 	int explicit,
1301 	int offline)
1302 {
1303 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1304 	int trans_delay_msecs;
1305 
1306 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1307 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1308 	if (!tg_pt_gp) {
1309 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1310 		pr_err("Unable to complete secondary state"
1311 				" transition\n");
1312 		return -EINVAL;
1313 	}
1314 	trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1315 	/*
1316 	 * Set the secondary ALUA target port access state to OFFLINE
1317 	 * or release the previously secondary state for struct se_port
1318 	 */
1319 	if (offline)
1320 		atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1321 	else
1322 		atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1323 
1324 	port->sep_tg_pt_secondary_stat = (explicit) ?
1325 			ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1326 			ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1327 
1328 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1329 		" to secondary access state: %s\n", (explicit) ? "explicit" :
1330 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1331 		tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1332 
1333 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1334 	/*
1335 	 * Do the optional transition delay after we set the secondary
1336 	 * ALUA access state.
1337 	 */
1338 	if (trans_delay_msecs != 0)
1339 		msleep_interruptible(trans_delay_msecs);
1340 	/*
1341 	 * See if we need to update the ALUA fabric port metadata for
1342 	 * secondary state and status
1343 	 */
1344 	if (port->sep_tg_pt_secondary_write_md) {
1345 		mutex_lock(&port->sep_tg_pt_md_mutex);
1346 		core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port);
1347 		mutex_unlock(&port->sep_tg_pt_md_mutex);
1348 	}
1349 
1350 	return 0;
1351 }
1352 
1353 struct t10_alua_lba_map *
1354 core_alua_allocate_lba_map(struct list_head *list,
1355 			   u64 first_lba, u64 last_lba)
1356 {
1357 	struct t10_alua_lba_map *lba_map;
1358 
1359 	lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1360 	if (!lba_map) {
1361 		pr_err("Unable to allocate struct t10_alua_lba_map\n");
1362 		return ERR_PTR(-ENOMEM);
1363 	}
1364 	INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1365 	lba_map->lba_map_first_lba = first_lba;
1366 	lba_map->lba_map_last_lba = last_lba;
1367 
1368 	list_add_tail(&lba_map->lba_map_list, list);
1369 	return lba_map;
1370 }
1371 
1372 int
1373 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1374 			       int pg_id, int state)
1375 {
1376 	struct t10_alua_lba_map_member *lba_map_mem;
1377 
1378 	list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1379 			    lba_map_mem_list) {
1380 		if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1381 			pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1382 			return -EINVAL;
1383 		}
1384 	}
1385 
1386 	lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1387 	if (!lba_map_mem) {
1388 		pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1389 		return -ENOMEM;
1390 	}
1391 	lba_map_mem->lba_map_mem_alua_state = state;
1392 	lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1393 
1394 	list_add_tail(&lba_map_mem->lba_map_mem_list,
1395 		      &lba_map->lba_map_mem_list);
1396 	return 0;
1397 }
1398 
1399 void
1400 core_alua_free_lba_map(struct list_head *lba_list)
1401 {
1402 	struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1403 	struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1404 
1405 	list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1406 				 lba_map_list) {
1407 		list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1408 					 &lba_map->lba_map_mem_list,
1409 					 lba_map_mem_list) {
1410 			list_del(&lba_map_mem->lba_map_mem_list);
1411 			kmem_cache_free(t10_alua_lba_map_mem_cache,
1412 					lba_map_mem);
1413 		}
1414 		list_del(&lba_map->lba_map_list);
1415 		kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1416 	}
1417 }
1418 
1419 void
1420 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1421 		      int segment_size, int segment_mult)
1422 {
1423 	struct list_head old_lba_map_list;
1424 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1425 	int activate = 0, supported;
1426 
1427 	INIT_LIST_HEAD(&old_lba_map_list);
1428 	spin_lock(&dev->t10_alua.lba_map_lock);
1429 	dev->t10_alua.lba_map_segment_size = segment_size;
1430 	dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1431 	list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1432 	if (lba_map_list) {
1433 		list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1434 		activate = 1;
1435 	}
1436 	spin_unlock(&dev->t10_alua.lba_map_lock);
1437 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1438 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1439 			    tg_pt_gp_list) {
1440 
1441 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1442 			continue;
1443 		supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1444 		if (activate)
1445 			supported |= ALUA_LBD_SUP;
1446 		else
1447 			supported &= ~ALUA_LBD_SUP;
1448 		tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1449 	}
1450 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1451 	core_alua_free_lba_map(&old_lba_map_list);
1452 }
1453 
1454 struct t10_alua_lu_gp *
1455 core_alua_allocate_lu_gp(const char *name, int def_group)
1456 {
1457 	struct t10_alua_lu_gp *lu_gp;
1458 
1459 	lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1460 	if (!lu_gp) {
1461 		pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1462 		return ERR_PTR(-ENOMEM);
1463 	}
1464 	INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1465 	INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1466 	spin_lock_init(&lu_gp->lu_gp_lock);
1467 	atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1468 
1469 	if (def_group) {
1470 		lu_gp->lu_gp_id = alua_lu_gps_counter++;
1471 		lu_gp->lu_gp_valid_id = 1;
1472 		alua_lu_gps_count++;
1473 	}
1474 
1475 	return lu_gp;
1476 }
1477 
1478 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1479 {
1480 	struct t10_alua_lu_gp *lu_gp_tmp;
1481 	u16 lu_gp_id_tmp;
1482 	/*
1483 	 * The lu_gp->lu_gp_id may only be set once..
1484 	 */
1485 	if (lu_gp->lu_gp_valid_id) {
1486 		pr_warn("ALUA LU Group already has a valid ID,"
1487 			" ignoring request\n");
1488 		return -EINVAL;
1489 	}
1490 
1491 	spin_lock(&lu_gps_lock);
1492 	if (alua_lu_gps_count == 0x0000ffff) {
1493 		pr_err("Maximum ALUA alua_lu_gps_count:"
1494 				" 0x0000ffff reached\n");
1495 		spin_unlock(&lu_gps_lock);
1496 		kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1497 		return -ENOSPC;
1498 	}
1499 again:
1500 	lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1501 				alua_lu_gps_counter++;
1502 
1503 	list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1504 		if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1505 			if (!lu_gp_id)
1506 				goto again;
1507 
1508 			pr_warn("ALUA Logical Unit Group ID: %hu"
1509 				" already exists, ignoring request\n",
1510 				lu_gp_id);
1511 			spin_unlock(&lu_gps_lock);
1512 			return -EINVAL;
1513 		}
1514 	}
1515 
1516 	lu_gp->lu_gp_id = lu_gp_id_tmp;
1517 	lu_gp->lu_gp_valid_id = 1;
1518 	list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1519 	alua_lu_gps_count++;
1520 	spin_unlock(&lu_gps_lock);
1521 
1522 	return 0;
1523 }
1524 
1525 static struct t10_alua_lu_gp_member *
1526 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1527 {
1528 	struct t10_alua_lu_gp_member *lu_gp_mem;
1529 
1530 	lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1531 	if (!lu_gp_mem) {
1532 		pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1533 		return ERR_PTR(-ENOMEM);
1534 	}
1535 	INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1536 	spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1537 	atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1538 
1539 	lu_gp_mem->lu_gp_mem_dev = dev;
1540 	dev->dev_alua_lu_gp_mem = lu_gp_mem;
1541 
1542 	return lu_gp_mem;
1543 }
1544 
1545 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1546 {
1547 	struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1548 	/*
1549 	 * Once we have reached this point, config_item_put() has
1550 	 * already been called from target_core_alua_drop_lu_gp().
1551 	 *
1552 	 * Here, we remove the *lu_gp from the global list so that
1553 	 * no associations can be made while we are releasing
1554 	 * struct t10_alua_lu_gp.
1555 	 */
1556 	spin_lock(&lu_gps_lock);
1557 	list_del(&lu_gp->lu_gp_node);
1558 	alua_lu_gps_count--;
1559 	spin_unlock(&lu_gps_lock);
1560 	/*
1561 	 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1562 	 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1563 	 * released with core_alua_put_lu_gp_from_name()
1564 	 */
1565 	while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1566 		cpu_relax();
1567 	/*
1568 	 * Release reference to struct t10_alua_lu_gp * from all associated
1569 	 * struct se_device.
1570 	 */
1571 	spin_lock(&lu_gp->lu_gp_lock);
1572 	list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1573 				&lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1574 		if (lu_gp_mem->lu_gp_assoc) {
1575 			list_del(&lu_gp_mem->lu_gp_mem_list);
1576 			lu_gp->lu_gp_members--;
1577 			lu_gp_mem->lu_gp_assoc = 0;
1578 		}
1579 		spin_unlock(&lu_gp->lu_gp_lock);
1580 		/*
1581 		 *
1582 		 * lu_gp_mem is associated with a single
1583 		 * struct se_device->dev_alua_lu_gp_mem, and is released when
1584 		 * struct se_device is released via core_alua_free_lu_gp_mem().
1585 		 *
1586 		 * If the passed lu_gp does NOT match the default_lu_gp, assume
1587 		 * we want to re-associate a given lu_gp_mem with default_lu_gp.
1588 		 */
1589 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1590 		if (lu_gp != default_lu_gp)
1591 			__core_alua_attach_lu_gp_mem(lu_gp_mem,
1592 					default_lu_gp);
1593 		else
1594 			lu_gp_mem->lu_gp = NULL;
1595 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1596 
1597 		spin_lock(&lu_gp->lu_gp_lock);
1598 	}
1599 	spin_unlock(&lu_gp->lu_gp_lock);
1600 
1601 	kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1602 }
1603 
1604 void core_alua_free_lu_gp_mem(struct se_device *dev)
1605 {
1606 	struct t10_alua_lu_gp *lu_gp;
1607 	struct t10_alua_lu_gp_member *lu_gp_mem;
1608 
1609 	lu_gp_mem = dev->dev_alua_lu_gp_mem;
1610 	if (!lu_gp_mem)
1611 		return;
1612 
1613 	while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1614 		cpu_relax();
1615 
1616 	spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1617 	lu_gp = lu_gp_mem->lu_gp;
1618 	if (lu_gp) {
1619 		spin_lock(&lu_gp->lu_gp_lock);
1620 		if (lu_gp_mem->lu_gp_assoc) {
1621 			list_del(&lu_gp_mem->lu_gp_mem_list);
1622 			lu_gp->lu_gp_members--;
1623 			lu_gp_mem->lu_gp_assoc = 0;
1624 		}
1625 		spin_unlock(&lu_gp->lu_gp_lock);
1626 		lu_gp_mem->lu_gp = NULL;
1627 	}
1628 	spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1629 
1630 	kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1631 }
1632 
1633 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1634 {
1635 	struct t10_alua_lu_gp *lu_gp;
1636 	struct config_item *ci;
1637 
1638 	spin_lock(&lu_gps_lock);
1639 	list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1640 		if (!lu_gp->lu_gp_valid_id)
1641 			continue;
1642 		ci = &lu_gp->lu_gp_group.cg_item;
1643 		if (!strcmp(config_item_name(ci), name)) {
1644 			atomic_inc(&lu_gp->lu_gp_ref_cnt);
1645 			spin_unlock(&lu_gps_lock);
1646 			return lu_gp;
1647 		}
1648 	}
1649 	spin_unlock(&lu_gps_lock);
1650 
1651 	return NULL;
1652 }
1653 
1654 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1655 {
1656 	spin_lock(&lu_gps_lock);
1657 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1658 	spin_unlock(&lu_gps_lock);
1659 }
1660 
1661 /*
1662  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1663  */
1664 void __core_alua_attach_lu_gp_mem(
1665 	struct t10_alua_lu_gp_member *lu_gp_mem,
1666 	struct t10_alua_lu_gp *lu_gp)
1667 {
1668 	spin_lock(&lu_gp->lu_gp_lock);
1669 	lu_gp_mem->lu_gp = lu_gp;
1670 	lu_gp_mem->lu_gp_assoc = 1;
1671 	list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1672 	lu_gp->lu_gp_members++;
1673 	spin_unlock(&lu_gp->lu_gp_lock);
1674 }
1675 
1676 /*
1677  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1678  */
1679 void __core_alua_drop_lu_gp_mem(
1680 	struct t10_alua_lu_gp_member *lu_gp_mem,
1681 	struct t10_alua_lu_gp *lu_gp)
1682 {
1683 	spin_lock(&lu_gp->lu_gp_lock);
1684 	list_del(&lu_gp_mem->lu_gp_mem_list);
1685 	lu_gp_mem->lu_gp = NULL;
1686 	lu_gp_mem->lu_gp_assoc = 0;
1687 	lu_gp->lu_gp_members--;
1688 	spin_unlock(&lu_gp->lu_gp_lock);
1689 }
1690 
1691 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1692 		const char *name, int def_group)
1693 {
1694 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1695 
1696 	tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1697 	if (!tg_pt_gp) {
1698 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1699 		return NULL;
1700 	}
1701 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1702 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1703 	mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1704 	spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1705 	atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1706 	INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1707 			  core_alua_do_transition_tg_pt_work);
1708 	tg_pt_gp->tg_pt_gp_dev = dev;
1709 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1710 		ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1711 	/*
1712 	 * Enable both explicit and implicit ALUA support by default
1713 	 */
1714 	tg_pt_gp->tg_pt_gp_alua_access_type =
1715 			TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1716 	/*
1717 	 * Set the default Active/NonOptimized Delay in milliseconds
1718 	 */
1719 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1720 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1721 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1722 
1723 	/*
1724 	 * Enable all supported states
1725 	 */
1726 	tg_pt_gp->tg_pt_gp_alua_supported_states =
1727 	    ALUA_T_SUP | ALUA_O_SUP |
1728 	    ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1729 
1730 	if (def_group) {
1731 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1732 		tg_pt_gp->tg_pt_gp_id =
1733 				dev->t10_alua.alua_tg_pt_gps_counter++;
1734 		tg_pt_gp->tg_pt_gp_valid_id = 1;
1735 		dev->t10_alua.alua_tg_pt_gps_count++;
1736 		list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1737 			      &dev->t10_alua.tg_pt_gps_list);
1738 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1739 	}
1740 
1741 	return tg_pt_gp;
1742 }
1743 
1744 int core_alua_set_tg_pt_gp_id(
1745 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1746 	u16 tg_pt_gp_id)
1747 {
1748 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1749 	struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1750 	u16 tg_pt_gp_id_tmp;
1751 
1752 	/*
1753 	 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1754 	 */
1755 	if (tg_pt_gp->tg_pt_gp_valid_id) {
1756 		pr_warn("ALUA TG PT Group already has a valid ID,"
1757 			" ignoring request\n");
1758 		return -EINVAL;
1759 	}
1760 
1761 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1762 	if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1763 		pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1764 			" 0x0000ffff reached\n");
1765 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1766 		kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1767 		return -ENOSPC;
1768 	}
1769 again:
1770 	tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1771 			dev->t10_alua.alua_tg_pt_gps_counter++;
1772 
1773 	list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1774 			tg_pt_gp_list) {
1775 		if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1776 			if (!tg_pt_gp_id)
1777 				goto again;
1778 
1779 			pr_err("ALUA Target Port Group ID: %hu already"
1780 				" exists, ignoring request\n", tg_pt_gp_id);
1781 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1782 			return -EINVAL;
1783 		}
1784 	}
1785 
1786 	tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1787 	tg_pt_gp->tg_pt_gp_valid_id = 1;
1788 	list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1789 			&dev->t10_alua.tg_pt_gps_list);
1790 	dev->t10_alua.alua_tg_pt_gps_count++;
1791 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1792 
1793 	return 0;
1794 }
1795 
1796 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1797 	struct se_port *port)
1798 {
1799 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1800 
1801 	tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1802 				GFP_KERNEL);
1803 	if (!tg_pt_gp_mem) {
1804 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1805 		return ERR_PTR(-ENOMEM);
1806 	}
1807 	INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1808 	spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1809 	atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1810 
1811 	tg_pt_gp_mem->tg_pt = port;
1812 	port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1813 
1814 	return tg_pt_gp_mem;
1815 }
1816 
1817 void core_alua_free_tg_pt_gp(
1818 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1819 {
1820 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1821 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1822 
1823 	/*
1824 	 * Once we have reached this point, config_item_put() has already
1825 	 * been called from target_core_alua_drop_tg_pt_gp().
1826 	 *
1827 	 * Here we remove *tg_pt_gp from the global list so that
1828 	 * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1829 	 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1830 	 */
1831 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1832 	list_del(&tg_pt_gp->tg_pt_gp_list);
1833 	dev->t10_alua.alua_tg_pt_gps_counter--;
1834 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1835 
1836 	flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1837 
1838 	/*
1839 	 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1840 	 * core_alua_get_tg_pt_gp_by_name() in
1841 	 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1842 	 * to be released with core_alua_put_tg_pt_gp_from_name().
1843 	 */
1844 	while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1845 		cpu_relax();
1846 
1847 	/*
1848 	 * Release reference to struct t10_alua_tg_pt_gp from all associated
1849 	 * struct se_port.
1850 	 */
1851 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1852 	list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1853 			&tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1854 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1855 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1856 			tg_pt_gp->tg_pt_gp_members--;
1857 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1858 		}
1859 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1860 		/*
1861 		 * tg_pt_gp_mem is associated with a single
1862 		 * se_port->sep_alua_tg_pt_gp_mem, and is released via
1863 		 * core_alua_free_tg_pt_gp_mem().
1864 		 *
1865 		 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1866 		 * assume we want to re-associate a given tg_pt_gp_mem with
1867 		 * default_tg_pt_gp.
1868 		 */
1869 		spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1870 		if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1871 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1872 					dev->t10_alua.default_tg_pt_gp);
1873 		} else
1874 			tg_pt_gp_mem->tg_pt_gp = NULL;
1875 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1876 
1877 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1878 	}
1879 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1880 
1881 	kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1882 }
1883 
1884 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1885 {
1886 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1887 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1888 
1889 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1890 	if (!tg_pt_gp_mem)
1891 		return;
1892 
1893 	while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1894 		cpu_relax();
1895 
1896 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1897 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1898 	if (tg_pt_gp) {
1899 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1900 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1901 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1902 			tg_pt_gp->tg_pt_gp_members--;
1903 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1904 		}
1905 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1906 		tg_pt_gp_mem->tg_pt_gp = NULL;
1907 	}
1908 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1909 
1910 	kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1911 }
1912 
1913 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1914 		struct se_device *dev, const char *name)
1915 {
1916 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1917 	struct config_item *ci;
1918 
1919 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1920 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1921 			tg_pt_gp_list) {
1922 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1923 			continue;
1924 		ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1925 		if (!strcmp(config_item_name(ci), name)) {
1926 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1927 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1928 			return tg_pt_gp;
1929 		}
1930 	}
1931 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1932 
1933 	return NULL;
1934 }
1935 
1936 static void core_alua_put_tg_pt_gp_from_name(
1937 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1938 {
1939 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1940 
1941 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1942 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1943 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1944 }
1945 
1946 /*
1947  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1948  */
1949 void __core_alua_attach_tg_pt_gp_mem(
1950 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1951 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1952 {
1953 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1954 	tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1955 	tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1956 	list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1957 			&tg_pt_gp->tg_pt_gp_mem_list);
1958 	tg_pt_gp->tg_pt_gp_members++;
1959 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1960 }
1961 
1962 /*
1963  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1964  */
1965 static void __core_alua_drop_tg_pt_gp_mem(
1966 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1967 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1968 {
1969 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1970 	list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1971 	tg_pt_gp_mem->tg_pt_gp = NULL;
1972 	tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1973 	tg_pt_gp->tg_pt_gp_members--;
1974 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1975 }
1976 
1977 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1978 {
1979 	struct config_item *tg_pt_ci;
1980 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1981 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1982 	ssize_t len = 0;
1983 
1984 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1985 	if (!tg_pt_gp_mem)
1986 		return len;
1987 
1988 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1989 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1990 	if (tg_pt_gp) {
1991 		tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1992 		len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1993 			" %hu\nTG Port Primary Access State: %s\nTG Port "
1994 			"Primary Access Status: %s\nTG Port Secondary Access"
1995 			" State: %s\nTG Port Secondary Access Status: %s\n",
1996 			config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1997 			core_alua_dump_state(atomic_read(
1998 					&tg_pt_gp->tg_pt_gp_alua_access_state)),
1999 			core_alua_dump_status(
2000 				tg_pt_gp->tg_pt_gp_alua_access_status),
2001 			(atomic_read(&port->sep_tg_pt_secondary_offline)) ?
2002 			"Offline" : "None",
2003 			core_alua_dump_status(port->sep_tg_pt_secondary_stat));
2004 	}
2005 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2006 
2007 	return len;
2008 }
2009 
2010 ssize_t core_alua_store_tg_pt_gp_info(
2011 	struct se_port *port,
2012 	const char *page,
2013 	size_t count)
2014 {
2015 	struct se_portal_group *tpg;
2016 	struct se_lun *lun;
2017 	struct se_device *dev = port->sep_lun->lun_se_dev;
2018 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
2019 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2020 	unsigned char buf[TG_PT_GROUP_NAME_BUF];
2021 	int move = 0;
2022 
2023 	tpg = port->sep_tpg;
2024 	lun = port->sep_lun;
2025 
2026 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
2027 	if (!tg_pt_gp_mem)
2028 		return 0;
2029 
2030 	if (count > TG_PT_GROUP_NAME_BUF) {
2031 		pr_err("ALUA Target Port Group alias too large!\n");
2032 		return -EINVAL;
2033 	}
2034 	memset(buf, 0, TG_PT_GROUP_NAME_BUF);
2035 	memcpy(buf, page, count);
2036 	/*
2037 	 * Any ALUA target port group alias besides "NULL" means we will be
2038 	 * making a new group association.
2039 	 */
2040 	if (strcmp(strstrip(buf), "NULL")) {
2041 		/*
2042 		 * core_alua_get_tg_pt_gp_by_name() will increment reference to
2043 		 * struct t10_alua_tg_pt_gp.  This reference is released with
2044 		 * core_alua_put_tg_pt_gp_from_name() below.
2045 		 */
2046 		tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
2047 					strstrip(buf));
2048 		if (!tg_pt_gp_new)
2049 			return -ENODEV;
2050 	}
2051 
2052 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2053 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
2054 	if (tg_pt_gp) {
2055 		/*
2056 		 * Clearing an existing tg_pt_gp association, and replacing
2057 		 * with the default_tg_pt_gp.
2058 		 */
2059 		if (!tg_pt_gp_new) {
2060 			pr_debug("Target_Core_ConfigFS: Moving"
2061 				" %s/tpgt_%hu/%s from ALUA Target Port Group:"
2062 				" alua/%s, ID: %hu back to"
2063 				" default_tg_pt_gp\n",
2064 				tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2065 				tpg->se_tpg_tfo->tpg_get_tag(tpg),
2066 				config_item_name(&lun->lun_group.cg_item),
2067 				config_item_name(
2068 					&tg_pt_gp->tg_pt_gp_group.cg_item),
2069 				tg_pt_gp->tg_pt_gp_id);
2070 
2071 			__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2072 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
2073 					dev->t10_alua.default_tg_pt_gp);
2074 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2075 
2076 			return count;
2077 		}
2078 		/*
2079 		 * Removing existing association of tg_pt_gp_mem with tg_pt_gp
2080 		 */
2081 		__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2082 		move = 1;
2083 	}
2084 	/*
2085 	 * Associate tg_pt_gp_mem with tg_pt_gp_new.
2086 	 */
2087 	__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
2088 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2089 	pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2090 		" Target Port Group: alua/%s, ID: %hu\n", (move) ?
2091 		"Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2092 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
2093 		config_item_name(&lun->lun_group.cg_item),
2094 		config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2095 		tg_pt_gp_new->tg_pt_gp_id);
2096 
2097 	core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2098 	return count;
2099 }
2100 
2101 ssize_t core_alua_show_access_type(
2102 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2103 	char *page)
2104 {
2105 	if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2106 	    (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2107 		return sprintf(page, "Implicit and Explicit\n");
2108 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2109 		return sprintf(page, "Implicit\n");
2110 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2111 		return sprintf(page, "Explicit\n");
2112 	else
2113 		return sprintf(page, "None\n");
2114 }
2115 
2116 ssize_t core_alua_store_access_type(
2117 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2118 	const char *page,
2119 	size_t count)
2120 {
2121 	unsigned long tmp;
2122 	int ret;
2123 
2124 	ret = kstrtoul(page, 0, &tmp);
2125 	if (ret < 0) {
2126 		pr_err("Unable to extract alua_access_type\n");
2127 		return ret;
2128 	}
2129 	if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2130 		pr_err("Illegal value for alua_access_type:"
2131 				" %lu\n", tmp);
2132 		return -EINVAL;
2133 	}
2134 	if (tmp == 3)
2135 		tg_pt_gp->tg_pt_gp_alua_access_type =
2136 			TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2137 	else if (tmp == 2)
2138 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2139 	else if (tmp == 1)
2140 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2141 	else
2142 		tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2143 
2144 	return count;
2145 }
2146 
2147 ssize_t core_alua_show_nonop_delay_msecs(
2148 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2149 	char *page)
2150 {
2151 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2152 }
2153 
2154 ssize_t core_alua_store_nonop_delay_msecs(
2155 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2156 	const char *page,
2157 	size_t count)
2158 {
2159 	unsigned long tmp;
2160 	int ret;
2161 
2162 	ret = kstrtoul(page, 0, &tmp);
2163 	if (ret < 0) {
2164 		pr_err("Unable to extract nonop_delay_msecs\n");
2165 		return ret;
2166 	}
2167 	if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2168 		pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2169 			" ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2170 			ALUA_MAX_NONOP_DELAY_MSECS);
2171 		return -EINVAL;
2172 	}
2173 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2174 
2175 	return count;
2176 }
2177 
2178 ssize_t core_alua_show_trans_delay_msecs(
2179 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2180 	char *page)
2181 {
2182 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2183 }
2184 
2185 ssize_t core_alua_store_trans_delay_msecs(
2186 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2187 	const char *page,
2188 	size_t count)
2189 {
2190 	unsigned long tmp;
2191 	int ret;
2192 
2193 	ret = kstrtoul(page, 0, &tmp);
2194 	if (ret < 0) {
2195 		pr_err("Unable to extract trans_delay_msecs\n");
2196 		return ret;
2197 	}
2198 	if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2199 		pr_err("Passed trans_delay_msecs: %lu, exceeds"
2200 			" ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2201 			ALUA_MAX_TRANS_DELAY_MSECS);
2202 		return -EINVAL;
2203 	}
2204 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2205 
2206 	return count;
2207 }
2208 
2209 ssize_t core_alua_show_implicit_trans_secs(
2210 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2211 	char *page)
2212 {
2213 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2214 }
2215 
2216 ssize_t core_alua_store_implicit_trans_secs(
2217 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2218 	const char *page,
2219 	size_t count)
2220 {
2221 	unsigned long tmp;
2222 	int ret;
2223 
2224 	ret = kstrtoul(page, 0, &tmp);
2225 	if (ret < 0) {
2226 		pr_err("Unable to extract implicit_trans_secs\n");
2227 		return ret;
2228 	}
2229 	if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2230 		pr_err("Passed implicit_trans_secs: %lu, exceeds"
2231 			" ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2232 			ALUA_MAX_IMPLICIT_TRANS_SECS);
2233 		return  -EINVAL;
2234 	}
2235 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2236 
2237 	return count;
2238 }
2239 
2240 ssize_t core_alua_show_preferred_bit(
2241 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2242 	char *page)
2243 {
2244 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2245 }
2246 
2247 ssize_t core_alua_store_preferred_bit(
2248 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2249 	const char *page,
2250 	size_t count)
2251 {
2252 	unsigned long tmp;
2253 	int ret;
2254 
2255 	ret = kstrtoul(page, 0, &tmp);
2256 	if (ret < 0) {
2257 		pr_err("Unable to extract preferred ALUA value\n");
2258 		return ret;
2259 	}
2260 	if ((tmp != 0) && (tmp != 1)) {
2261 		pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2262 		return -EINVAL;
2263 	}
2264 	tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2265 
2266 	return count;
2267 }
2268 
2269 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2270 {
2271 	if (!lun->lun_sep)
2272 		return -ENODEV;
2273 
2274 	return sprintf(page, "%d\n",
2275 		atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
2276 }
2277 
2278 ssize_t core_alua_store_offline_bit(
2279 	struct se_lun *lun,
2280 	const char *page,
2281 	size_t count)
2282 {
2283 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2284 	unsigned long tmp;
2285 	int ret;
2286 
2287 	if (!lun->lun_sep)
2288 		return -ENODEV;
2289 
2290 	ret = kstrtoul(page, 0, &tmp);
2291 	if (ret < 0) {
2292 		pr_err("Unable to extract alua_tg_pt_offline value\n");
2293 		return ret;
2294 	}
2295 	if ((tmp != 0) && (tmp != 1)) {
2296 		pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2297 				tmp);
2298 		return -EINVAL;
2299 	}
2300 	tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
2301 	if (!tg_pt_gp_mem) {
2302 		pr_err("Unable to locate *tg_pt_gp_mem\n");
2303 		return -EINVAL;
2304 	}
2305 
2306 	ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
2307 			lun->lun_sep, 0, (int)tmp);
2308 	if (ret < 0)
2309 		return -EINVAL;
2310 
2311 	return count;
2312 }
2313 
2314 ssize_t core_alua_show_secondary_status(
2315 	struct se_lun *lun,
2316 	char *page)
2317 {
2318 	return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
2319 }
2320 
2321 ssize_t core_alua_store_secondary_status(
2322 	struct se_lun *lun,
2323 	const char *page,
2324 	size_t count)
2325 {
2326 	unsigned long tmp;
2327 	int ret;
2328 
2329 	ret = kstrtoul(page, 0, &tmp);
2330 	if (ret < 0) {
2331 		pr_err("Unable to extract alua_tg_pt_status\n");
2332 		return ret;
2333 	}
2334 	if ((tmp != ALUA_STATUS_NONE) &&
2335 	    (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2336 	    (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2337 		pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2338 				tmp);
2339 		return -EINVAL;
2340 	}
2341 	lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
2342 
2343 	return count;
2344 }
2345 
2346 ssize_t core_alua_show_secondary_write_metadata(
2347 	struct se_lun *lun,
2348 	char *page)
2349 {
2350 	return sprintf(page, "%d\n",
2351 			lun->lun_sep->sep_tg_pt_secondary_write_md);
2352 }
2353 
2354 ssize_t core_alua_store_secondary_write_metadata(
2355 	struct se_lun *lun,
2356 	const char *page,
2357 	size_t count)
2358 {
2359 	unsigned long tmp;
2360 	int ret;
2361 
2362 	ret = kstrtoul(page, 0, &tmp);
2363 	if (ret < 0) {
2364 		pr_err("Unable to extract alua_tg_pt_write_md\n");
2365 		return ret;
2366 	}
2367 	if ((tmp != 0) && (tmp != 1)) {
2368 		pr_err("Illegal value for alua_tg_pt_write_md:"
2369 				" %lu\n", tmp);
2370 		return -EINVAL;
2371 	}
2372 	lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
2373 
2374 	return count;
2375 }
2376 
2377 int core_setup_alua(struct se_device *dev)
2378 {
2379 	if (!(dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) &&
2380 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2381 		struct t10_alua_lu_gp_member *lu_gp_mem;
2382 
2383 		/*
2384 		 * Associate this struct se_device with the default ALUA
2385 		 * LUN Group.
2386 		 */
2387 		lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2388 		if (IS_ERR(lu_gp_mem))
2389 			return PTR_ERR(lu_gp_mem);
2390 
2391 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2392 		__core_alua_attach_lu_gp_mem(lu_gp_mem,
2393 				default_lu_gp);
2394 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2395 
2396 		pr_debug("%s: Adding to default ALUA LU Group:"
2397 			" core/alua/lu_gps/default_lu_gp\n",
2398 			dev->transport->name);
2399 	}
2400 
2401 	return 0;
2402 }
2403