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_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
396 
397 				spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
398 
399 				if (!core_alua_do_port_transition(tg_pt_gp,
400 						dev, l_port, nacl,
401 						alua_access_state, 1))
402 					found = true;
403 
404 				spin_lock(&dev->t10_alua.tg_pt_gps_lock);
405 				atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
406 				break;
407 			}
408 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
409 		} else {
410 			/*
411 			 * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
412 			 * the Target Port in question for the the incoming
413 			 * SET_TARGET_PORT_GROUPS op.
414 			 */
415 			rtpi = get_unaligned_be16(ptr + 2);
416 			/*
417 			 * Locate the matching relative target port identifier
418 			 * for the struct se_device storage object.
419 			 */
420 			spin_lock(&dev->se_port_lock);
421 			list_for_each_entry(port, &dev->dev_sep_list,
422 							sep_list) {
423 				if (port->sep_rtpi != rtpi)
424 					continue;
425 
426 				tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
427 
428 				spin_unlock(&dev->se_port_lock);
429 
430 				if (!core_alua_set_tg_pt_secondary_state(
431 						tg_pt_gp_mem, port, 1, 1))
432 					found = true;
433 
434 				spin_lock(&dev->se_port_lock);
435 				break;
436 			}
437 			spin_unlock(&dev->se_port_lock);
438 		}
439 
440 		if (!found) {
441 			rc = TCM_INVALID_PARAMETER_LIST;
442 			goto out;
443 		}
444 
445 		ptr += 4;
446 		len += 4;
447 	}
448 
449 out:
450 	transport_kunmap_data_sg(cmd);
451 	if (!rc)
452 		target_complete_cmd(cmd, GOOD);
453 	return rc;
454 }
455 
456 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
457 {
458 	/*
459 	 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
460 	 * The ALUA additional sense code qualifier (ASCQ) is determined
461 	 * by the ALUA primary or secondary access state..
462 	 */
463 	pr_debug("[%s]: ALUA TG Port not available, "
464 		"SenseKey: NOT_READY, ASC/ASCQ: "
465 		"0x04/0x%02x\n",
466 		cmd->se_tfo->get_fabric_name(), alua_ascq);
467 
468 	cmd->scsi_asc = 0x04;
469 	cmd->scsi_ascq = alua_ascq;
470 }
471 
472 static inline void core_alua_state_nonoptimized(
473 	struct se_cmd *cmd,
474 	unsigned char *cdb,
475 	int nonop_delay_msecs)
476 {
477 	/*
478 	 * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
479 	 * later to determine if processing of this cmd needs to be
480 	 * temporarily delayed for the Active/NonOptimized primary access state.
481 	 */
482 	cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
483 	cmd->alua_nonop_delay = nonop_delay_msecs;
484 }
485 
486 static inline int core_alua_state_lba_dependent(
487 	struct se_cmd *cmd,
488 	struct t10_alua_tg_pt_gp *tg_pt_gp)
489 {
490 	struct se_device *dev = cmd->se_dev;
491 	u64 segment_size, segment_mult, sectors, lba;
492 
493 	/* Only need to check for cdb actually containing LBAs */
494 	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
495 		return 0;
496 
497 	spin_lock(&dev->t10_alua.lba_map_lock);
498 	segment_size = dev->t10_alua.lba_map_segment_size;
499 	segment_mult = dev->t10_alua.lba_map_segment_multiplier;
500 	sectors = cmd->data_length / dev->dev_attrib.block_size;
501 
502 	lba = cmd->t_task_lba;
503 	while (lba < cmd->t_task_lba + sectors) {
504 		struct t10_alua_lba_map *cur_map = NULL, *map;
505 		struct t10_alua_lba_map_member *map_mem;
506 
507 		list_for_each_entry(map, &dev->t10_alua.lba_map_list,
508 				    lba_map_list) {
509 			u64 start_lba, last_lba;
510 			u64 first_lba = map->lba_map_first_lba;
511 
512 			if (segment_mult) {
513 				u64 tmp = lba;
514 				start_lba = do_div(tmp, segment_size * segment_mult);
515 
516 				last_lba = first_lba + segment_size - 1;
517 				if (start_lba >= first_lba &&
518 				    start_lba <= last_lba) {
519 					lba += segment_size;
520 					cur_map = map;
521 					break;
522 				}
523 			} else {
524 				last_lba = map->lba_map_last_lba;
525 				if (lba >= first_lba && lba <= last_lba) {
526 					lba = last_lba + 1;
527 					cur_map = map;
528 					break;
529 				}
530 			}
531 		}
532 		if (!cur_map) {
533 			spin_unlock(&dev->t10_alua.lba_map_lock);
534 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
535 			return 1;
536 		}
537 		list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
538 				    lba_map_mem_list) {
539 			if (map_mem->lba_map_mem_alua_pg_id !=
540 			    tg_pt_gp->tg_pt_gp_id)
541 				continue;
542 			switch(map_mem->lba_map_mem_alua_state) {
543 			case ALUA_ACCESS_STATE_STANDBY:
544 				spin_unlock(&dev->t10_alua.lba_map_lock);
545 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
546 				return 1;
547 			case ALUA_ACCESS_STATE_UNAVAILABLE:
548 				spin_unlock(&dev->t10_alua.lba_map_lock);
549 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
550 				return 1;
551 			default:
552 				break;
553 			}
554 		}
555 	}
556 	spin_unlock(&dev->t10_alua.lba_map_lock);
557 	return 0;
558 }
559 
560 static inline int core_alua_state_standby(
561 	struct se_cmd *cmd,
562 	unsigned char *cdb)
563 {
564 	/*
565 	 * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
566 	 * spc4r17 section 5.9.2.4.4
567 	 */
568 	switch (cdb[0]) {
569 	case INQUIRY:
570 	case LOG_SELECT:
571 	case LOG_SENSE:
572 	case MODE_SELECT:
573 	case MODE_SENSE:
574 	case REPORT_LUNS:
575 	case RECEIVE_DIAGNOSTIC:
576 	case SEND_DIAGNOSTIC:
577 	case READ_CAPACITY:
578 		return 0;
579 	case SERVICE_ACTION_IN_16:
580 		switch (cdb[1] & 0x1f) {
581 		case SAI_READ_CAPACITY_16:
582 			return 0;
583 		default:
584 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
585 			return 1;
586 		}
587 	case MAINTENANCE_IN:
588 		switch (cdb[1] & 0x1f) {
589 		case MI_REPORT_TARGET_PGS:
590 			return 0;
591 		default:
592 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
593 			return 1;
594 		}
595 	case MAINTENANCE_OUT:
596 		switch (cdb[1]) {
597 		case MO_SET_TARGET_PGS:
598 			return 0;
599 		default:
600 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
601 			return 1;
602 		}
603 	case REQUEST_SENSE:
604 	case PERSISTENT_RESERVE_IN:
605 	case PERSISTENT_RESERVE_OUT:
606 	case READ_BUFFER:
607 	case WRITE_BUFFER:
608 		return 0;
609 	default:
610 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
611 		return 1;
612 	}
613 
614 	return 0;
615 }
616 
617 static inline int core_alua_state_unavailable(
618 	struct se_cmd *cmd,
619 	unsigned char *cdb)
620 {
621 	/*
622 	 * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
623 	 * spc4r17 section 5.9.2.4.5
624 	 */
625 	switch (cdb[0]) {
626 	case INQUIRY:
627 	case REPORT_LUNS:
628 		return 0;
629 	case MAINTENANCE_IN:
630 		switch (cdb[1] & 0x1f) {
631 		case MI_REPORT_TARGET_PGS:
632 			return 0;
633 		default:
634 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
635 			return 1;
636 		}
637 	case MAINTENANCE_OUT:
638 		switch (cdb[1]) {
639 		case MO_SET_TARGET_PGS:
640 			return 0;
641 		default:
642 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
643 			return 1;
644 		}
645 	case REQUEST_SENSE:
646 	case READ_BUFFER:
647 	case WRITE_BUFFER:
648 		return 0;
649 	default:
650 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
651 		return 1;
652 	}
653 
654 	return 0;
655 }
656 
657 static inline int core_alua_state_transition(
658 	struct se_cmd *cmd,
659 	unsigned char *cdb)
660 {
661 	/*
662 	 * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
663 	 * spc4r17 section 5.9.2.5
664 	 */
665 	switch (cdb[0]) {
666 	case INQUIRY:
667 	case REPORT_LUNS:
668 		return 0;
669 	case MAINTENANCE_IN:
670 		switch (cdb[1] & 0x1f) {
671 		case MI_REPORT_TARGET_PGS:
672 			return 0;
673 		default:
674 			set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
675 			return 1;
676 		}
677 	case REQUEST_SENSE:
678 	case READ_BUFFER:
679 	case WRITE_BUFFER:
680 		return 0;
681 	default:
682 		set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
683 		return 1;
684 	}
685 
686 	return 0;
687 }
688 
689 /*
690  * return 1: Is used to signal LUN not accessible, and check condition/not ready
691  * return 0: Used to signal success
692  * return -1: Used to signal failure, and invalid cdb field
693  */
694 sense_reason_t
695 target_alua_state_check(struct se_cmd *cmd)
696 {
697 	struct se_device *dev = cmd->se_dev;
698 	unsigned char *cdb = cmd->t_task_cdb;
699 	struct se_lun *lun = cmd->se_lun;
700 	struct se_port *port = lun->lun_sep;
701 	struct t10_alua_tg_pt_gp *tg_pt_gp;
702 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
703 	int out_alua_state, nonop_delay_msecs;
704 
705 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
706 		return 0;
707 	if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV)
708 		return 0;
709 
710 	if (!port)
711 		return 0;
712 	/*
713 	 * First, check for a struct se_port specific secondary ALUA target port
714 	 * access state: OFFLINE
715 	 */
716 	if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
717 		pr_debug("ALUA: Got secondary offline status for local"
718 				" target port\n");
719 		set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
720 		return TCM_CHECK_CONDITION_NOT_READY;
721 	}
722 	 /*
723 	 * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
724 	 * ALUA target port group, to obtain current ALUA access state.
725 	 * Otherwise look for the underlying struct se_device association with
726 	 * a ALUA logical unit group.
727 	 */
728 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
729 	if (!tg_pt_gp_mem)
730 		return 0;
731 
732 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
733 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
734 	out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
735 	nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
736 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
737 	/*
738 	 * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
739 	 * statement so the compiler knows explicitly to check this case first.
740 	 * For the Optimized ALUA access state case, we want to process the
741 	 * incoming fabric cmd ASAP..
742 	 */
743 	if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
744 		return 0;
745 
746 	switch (out_alua_state) {
747 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
748 		core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
749 		break;
750 	case ALUA_ACCESS_STATE_STANDBY:
751 		if (core_alua_state_standby(cmd, cdb))
752 			return TCM_CHECK_CONDITION_NOT_READY;
753 		break;
754 	case ALUA_ACCESS_STATE_UNAVAILABLE:
755 		if (core_alua_state_unavailable(cmd, cdb))
756 			return TCM_CHECK_CONDITION_NOT_READY;
757 		break;
758 	case ALUA_ACCESS_STATE_TRANSITION:
759 		if (core_alua_state_transition(cmd, cdb))
760 			return TCM_CHECK_CONDITION_NOT_READY;
761 		break;
762 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
763 		if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
764 			return TCM_CHECK_CONDITION_NOT_READY;
765 		break;
766 	/*
767 	 * OFFLINE is a secondary ALUA target port group access state, that is
768 	 * handled above with struct se_port->sep_tg_pt_secondary_offline=1
769 	 */
770 	case ALUA_ACCESS_STATE_OFFLINE:
771 	default:
772 		pr_err("Unknown ALUA access state: 0x%02x\n",
773 				out_alua_state);
774 		return TCM_INVALID_CDB_FIELD;
775 	}
776 
777 	return 0;
778 }
779 
780 /*
781  * Check implicit and explicit ALUA state change request.
782  */
783 static sense_reason_t
784 core_alua_check_transition(int state, int valid, int *primary)
785 {
786 	/*
787 	 * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
788 	 * defined as primary target port asymmetric access states.
789 	 */
790 	switch (state) {
791 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
792 		if (!(valid & ALUA_AO_SUP))
793 			goto not_supported;
794 		*primary = 1;
795 		break;
796 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
797 		if (!(valid & ALUA_AN_SUP))
798 			goto not_supported;
799 		*primary = 1;
800 		break;
801 	case ALUA_ACCESS_STATE_STANDBY:
802 		if (!(valid & ALUA_S_SUP))
803 			goto not_supported;
804 		*primary = 1;
805 		break;
806 	case ALUA_ACCESS_STATE_UNAVAILABLE:
807 		if (!(valid & ALUA_U_SUP))
808 			goto not_supported;
809 		*primary = 1;
810 		break;
811 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
812 		if (!(valid & ALUA_LBD_SUP))
813 			goto not_supported;
814 		*primary = 1;
815 		break;
816 	case ALUA_ACCESS_STATE_OFFLINE:
817 		/*
818 		 * OFFLINE state is defined as a secondary target port
819 		 * asymmetric access state.
820 		 */
821 		if (!(valid & ALUA_O_SUP))
822 			goto not_supported;
823 		*primary = 0;
824 		break;
825 	case ALUA_ACCESS_STATE_TRANSITION:
826 		/*
827 		 * Transitioning is set internally, and
828 		 * cannot be selected manually.
829 		 */
830 		goto not_supported;
831 	default:
832 		pr_err("Unknown ALUA access state: 0x%02x\n", state);
833 		return TCM_INVALID_PARAMETER_LIST;
834 	}
835 
836 	return 0;
837 
838 not_supported:
839 	pr_err("ALUA access state %s not supported",
840 	       core_alua_dump_state(state));
841 	return TCM_INVALID_PARAMETER_LIST;
842 }
843 
844 static char *core_alua_dump_state(int state)
845 {
846 	switch (state) {
847 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
848 		return "Active/Optimized";
849 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
850 		return "Active/NonOptimized";
851 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
852 		return "LBA Dependent";
853 	case ALUA_ACCESS_STATE_STANDBY:
854 		return "Standby";
855 	case ALUA_ACCESS_STATE_UNAVAILABLE:
856 		return "Unavailable";
857 	case ALUA_ACCESS_STATE_OFFLINE:
858 		return "Offline";
859 	case ALUA_ACCESS_STATE_TRANSITION:
860 		return "Transitioning";
861 	default:
862 		return "Unknown";
863 	}
864 
865 	return NULL;
866 }
867 
868 char *core_alua_dump_status(int status)
869 {
870 	switch (status) {
871 	case ALUA_STATUS_NONE:
872 		return "None";
873 	case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
874 		return "Altered by Explicit STPG";
875 	case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
876 		return "Altered by Implicit ALUA";
877 	default:
878 		return "Unknown";
879 	}
880 
881 	return NULL;
882 }
883 
884 /*
885  * Used by fabric modules to determine when we need to delay processing
886  * for the Active/NonOptimized paths..
887  */
888 int core_alua_check_nonop_delay(
889 	struct se_cmd *cmd)
890 {
891 	if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
892 		return 0;
893 	if (in_interrupt())
894 		return 0;
895 	/*
896 	 * The ALUA Active/NonOptimized access state delay can be disabled
897 	 * in via configfs with a value of zero
898 	 */
899 	if (!cmd->alua_nonop_delay)
900 		return 0;
901 	/*
902 	 * struct se_cmd->alua_nonop_delay gets set by a target port group
903 	 * defined interval in core_alua_state_nonoptimized()
904 	 */
905 	msleep_interruptible(cmd->alua_nonop_delay);
906 	return 0;
907 }
908 EXPORT_SYMBOL(core_alua_check_nonop_delay);
909 
910 /*
911  * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
912  *
913  */
914 static int core_alua_write_tpg_metadata(
915 	const char *path,
916 	unsigned char *md_buf,
917 	u32 md_buf_len)
918 {
919 	struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
920 	int ret;
921 
922 	if (IS_ERR(file)) {
923 		pr_err("filp_open(%s) for ALUA metadata failed\n", path);
924 		return -ENODEV;
925 	}
926 	ret = kernel_write(file, md_buf, md_buf_len, 0);
927 	if (ret < 0)
928 		pr_err("Error writing ALUA metadata file: %s\n", path);
929 	fput(file);
930 	return (ret < 0) ? -EIO : 0;
931 }
932 
933 /*
934  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
935  */
936 static int core_alua_update_tpg_primary_metadata(
937 	struct t10_alua_tg_pt_gp *tg_pt_gp)
938 {
939 	unsigned char *md_buf;
940 	struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
941 	char path[ALUA_METADATA_PATH_LEN];
942 	int len, rc;
943 
944 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
945 	if (!md_buf) {
946 		pr_err("Unable to allocate buf for ALUA metadata\n");
947 		return -ENOMEM;
948 	}
949 
950 	memset(path, 0, ALUA_METADATA_PATH_LEN);
951 
952 	len = snprintf(md_buf, ALUA_MD_BUF_LEN,
953 			"tg_pt_gp_id=%hu\n"
954 			"alua_access_state=0x%02x\n"
955 			"alua_access_status=0x%02x\n",
956 			tg_pt_gp->tg_pt_gp_id,
957 			tg_pt_gp->tg_pt_gp_alua_pending_state,
958 			tg_pt_gp->tg_pt_gp_alua_access_status);
959 
960 	snprintf(path, ALUA_METADATA_PATH_LEN,
961 		"/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
962 		config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
963 
964 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
965 	kfree(md_buf);
966 	return rc;
967 }
968 
969 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
970 {
971 	struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
972 		struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work.work);
973 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
974 	struct se_dev_entry *se_deve;
975 	struct se_lun_acl *lacl;
976 	struct se_port *port;
977 	struct t10_alua_tg_pt_gp_member *mem;
978 	bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
979 			 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
980 
981 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
982 	list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
983 				tg_pt_gp_mem_list) {
984 		port = mem->tg_pt;
985 		/*
986 		 * After an implicit target port asymmetric access state
987 		 * change, a device server shall establish a unit attention
988 		 * condition for the initiator port associated with every I_T
989 		 * nexus with the additional sense code set to ASYMMETRIC
990 		 * ACCESS STATE CHANGED.
991 		 *
992 		 * After an explicit target port asymmetric access state
993 		 * change, a device server shall establish a unit attention
994 		 * condition with the additional sense code set to ASYMMETRIC
995 		 * ACCESS STATE CHANGED for the initiator port associated with
996 		 * every I_T nexus other than the I_T nexus on which the SET
997 		 * TARGET PORT GROUPS command
998 		 */
999 		atomic_inc_mb(&mem->tg_pt_gp_mem_ref_cnt);
1000 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1001 
1002 		spin_lock_bh(&port->sep_alua_lock);
1003 		list_for_each_entry(se_deve, &port->sep_alua_list,
1004 					alua_port_list) {
1005 			lacl = se_deve->se_lun_acl;
1006 			/*
1007 			 * se_deve->se_lun_acl pointer may be NULL for a
1008 			 * entry created without explicit Node+MappedLUN ACLs
1009 			 */
1010 			if (!lacl)
1011 				continue;
1012 
1013 			if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
1014 			     ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
1015 			   (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
1016 			    (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl) &&
1017 			   (tg_pt_gp->tg_pt_gp_alua_port != NULL) &&
1018 			    (tg_pt_gp->tg_pt_gp_alua_port == port))
1019 				continue;
1020 
1021 			core_scsi3_ua_allocate(lacl->se_lun_nacl,
1022 				se_deve->mapped_lun, 0x2A,
1023 				ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1024 		}
1025 		spin_unlock_bh(&port->sep_alua_lock);
1026 
1027 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1028 		atomic_dec_mb(&mem->tg_pt_gp_mem_ref_cnt);
1029 	}
1030 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1031 	/*
1032 	 * Update the ALUA metadata buf that has been allocated in
1033 	 * core_alua_do_port_transition(), this metadata will be written
1034 	 * to struct file.
1035 	 *
1036 	 * Note that there is the case where we do not want to update the
1037 	 * metadata when the saved metadata is being parsed in userspace
1038 	 * when setting the existing port access state and access status.
1039 	 *
1040 	 * Also note that the failure to write out the ALUA metadata to
1041 	 * struct file does NOT affect the actual ALUA transition.
1042 	 */
1043 	if (tg_pt_gp->tg_pt_gp_write_metadata) {
1044 		mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1045 		core_alua_update_tpg_primary_metadata(tg_pt_gp);
1046 		mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1047 	}
1048 	/*
1049 	 * Set the current primary ALUA access state to the requested new state
1050 	 */
1051 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1052 		   tg_pt_gp->tg_pt_gp_alua_pending_state);
1053 
1054 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1055 		" from primary access state %s to %s\n", (explicit) ? "explicit" :
1056 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1057 		tg_pt_gp->tg_pt_gp_id,
1058 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1059 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1060 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1061 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1062 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1063 
1064 	if (tg_pt_gp->tg_pt_gp_transition_complete)
1065 		complete(tg_pt_gp->tg_pt_gp_transition_complete);
1066 }
1067 
1068 static int core_alua_do_transition_tg_pt(
1069 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1070 	int new_state,
1071 	int explicit)
1072 {
1073 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1074 	DECLARE_COMPLETION_ONSTACK(wait);
1075 
1076 	/* Nothing to be done here */
1077 	if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1078 		return 0;
1079 
1080 	if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1081 		return -EAGAIN;
1082 
1083 	/*
1084 	 * Flush any pending transitions
1085 	 */
1086 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs &&
1087 	    atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) ==
1088 	    ALUA_ACCESS_STATE_TRANSITION) {
1089 		/* Just in case */
1090 		tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1091 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1092 		flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1093 		wait_for_completion(&wait);
1094 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1095 		return 0;
1096 	}
1097 
1098 	/*
1099 	 * Save the old primary ALUA access state, and set the current state
1100 	 * to ALUA_ACCESS_STATE_TRANSITION.
1101 	 */
1102 	tg_pt_gp->tg_pt_gp_alua_previous_state =
1103 		atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1104 	tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1105 
1106 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1107 			ALUA_ACCESS_STATE_TRANSITION);
1108 	tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1109 				ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1110 				ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1111 
1112 	/*
1113 	 * Check for the optional ALUA primary state transition delay
1114 	 */
1115 	if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1116 		msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1117 
1118 	/*
1119 	 * Take a reference for workqueue item
1120 	 */
1121 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1122 	atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1123 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1124 
1125 	if (!explicit && tg_pt_gp->tg_pt_gp_implicit_trans_secs) {
1126 		unsigned long transition_tmo;
1127 
1128 		transition_tmo = tg_pt_gp->tg_pt_gp_implicit_trans_secs * HZ;
1129 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1130 				   &tg_pt_gp->tg_pt_gp_transition_work,
1131 				   transition_tmo);
1132 	} else {
1133 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1134 		queue_delayed_work(tg_pt_gp->tg_pt_gp_dev->tmr_wq,
1135 				   &tg_pt_gp->tg_pt_gp_transition_work, 0);
1136 		wait_for_completion(&wait);
1137 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1138 	}
1139 
1140 	return 0;
1141 }
1142 
1143 int core_alua_do_port_transition(
1144 	struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1145 	struct se_device *l_dev,
1146 	struct se_port *l_port,
1147 	struct se_node_acl *l_nacl,
1148 	int new_state,
1149 	int explicit)
1150 {
1151 	struct se_device *dev;
1152 	struct t10_alua_lu_gp *lu_gp;
1153 	struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1154 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1155 	int primary, valid_states, rc = 0;
1156 
1157 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1158 	if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1159 		return -EINVAL;
1160 
1161 	local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1162 	spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1163 	lu_gp = local_lu_gp_mem->lu_gp;
1164 	atomic_inc(&lu_gp->lu_gp_ref_cnt);
1165 	spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1166 	/*
1167 	 * For storage objects that are members of the 'default_lu_gp',
1168 	 * we only do transition on the passed *l_tp_pt_gp, and not
1169 	 * on all of the matching target port groups IDs in default_lu_gp.
1170 	 */
1171 	if (!lu_gp->lu_gp_id) {
1172 		/*
1173 		 * core_alua_do_transition_tg_pt() will always return
1174 		 * success.
1175 		 */
1176 		l_tg_pt_gp->tg_pt_gp_alua_port = l_port;
1177 		l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1178 		rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1179 						   new_state, explicit);
1180 		atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1181 		return rc;
1182 	}
1183 	/*
1184 	 * For all other LU groups aside from 'default_lu_gp', walk all of
1185 	 * the associated storage objects looking for a matching target port
1186 	 * group ID from the local target port group.
1187 	 */
1188 	spin_lock(&lu_gp->lu_gp_lock);
1189 	list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1190 				lu_gp_mem_list) {
1191 
1192 		dev = lu_gp_mem->lu_gp_mem_dev;
1193 		atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1194 		spin_unlock(&lu_gp->lu_gp_lock);
1195 
1196 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1197 		list_for_each_entry(tg_pt_gp,
1198 				&dev->t10_alua.tg_pt_gps_list,
1199 				tg_pt_gp_list) {
1200 
1201 			if (!tg_pt_gp->tg_pt_gp_valid_id)
1202 				continue;
1203 			/*
1204 			 * If the target behavior port asymmetric access state
1205 			 * is changed for any target port group accessible via
1206 			 * a logical unit within a LU group, the target port
1207 			 * behavior group asymmetric access states for the same
1208 			 * target port group accessible via other logical units
1209 			 * in that LU group will also change.
1210 			 */
1211 			if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1212 				continue;
1213 
1214 			if (l_tg_pt_gp == tg_pt_gp) {
1215 				tg_pt_gp->tg_pt_gp_alua_port = l_port;
1216 				tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1217 			} else {
1218 				tg_pt_gp->tg_pt_gp_alua_port = NULL;
1219 				tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1220 			}
1221 			atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1222 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1223 			/*
1224 			 * core_alua_do_transition_tg_pt() will always return
1225 			 * success.
1226 			 */
1227 			rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1228 					new_state, explicit);
1229 
1230 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1231 			atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1232 			if (rc)
1233 				break;
1234 		}
1235 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1236 
1237 		spin_lock(&lu_gp->lu_gp_lock);
1238 		atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1239 	}
1240 	spin_unlock(&lu_gp->lu_gp_lock);
1241 
1242 	if (!rc) {
1243 		pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1244 			 " Group IDs: %hu %s transition to primary state: %s\n",
1245 			 config_item_name(&lu_gp->lu_gp_group.cg_item),
1246 			 l_tg_pt_gp->tg_pt_gp_id,
1247 			 (explicit) ? "explicit" : "implicit",
1248 			 core_alua_dump_state(new_state));
1249 	}
1250 
1251 	atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1252 	return rc;
1253 }
1254 
1255 /*
1256  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
1257  */
1258 static int core_alua_update_tpg_secondary_metadata(
1259 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1260 	struct se_port *port)
1261 {
1262 	unsigned char *md_buf;
1263 	struct se_portal_group *se_tpg = port->sep_tpg;
1264 	char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1265 	int len, rc;
1266 
1267 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1268 	if (!md_buf) {
1269 		pr_err("Unable to allocate buf for ALUA metadata\n");
1270 		return -ENOMEM;
1271 	}
1272 
1273 	memset(path, 0, ALUA_METADATA_PATH_LEN);
1274 	memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1275 
1276 	len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1277 			se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1278 
1279 	if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1280 		snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1281 				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1282 
1283 	len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1284 			"alua_tg_pt_status=0x%02x\n",
1285 			atomic_read(&port->sep_tg_pt_secondary_offline),
1286 			port->sep_tg_pt_secondary_stat);
1287 
1288 	snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
1289 			se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1290 			port->sep_lun->unpacked_lun);
1291 
1292 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
1293 	kfree(md_buf);
1294 
1295 	return rc;
1296 }
1297 
1298 static int core_alua_set_tg_pt_secondary_state(
1299 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1300 	struct se_port *port,
1301 	int explicit,
1302 	int offline)
1303 {
1304 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1305 	int trans_delay_msecs;
1306 
1307 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1308 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1309 	if (!tg_pt_gp) {
1310 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1311 		pr_err("Unable to complete secondary state"
1312 				" transition\n");
1313 		return -EINVAL;
1314 	}
1315 	trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1316 	/*
1317 	 * Set the secondary ALUA target port access state to OFFLINE
1318 	 * or release the previously secondary state for struct se_port
1319 	 */
1320 	if (offline)
1321 		atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1322 	else
1323 		atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1324 
1325 	port->sep_tg_pt_secondary_stat = (explicit) ?
1326 			ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1327 			ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1328 
1329 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1330 		" to secondary access state: %s\n", (explicit) ? "explicit" :
1331 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1332 		tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1333 
1334 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1335 	/*
1336 	 * Do the optional transition delay after we set the secondary
1337 	 * ALUA access state.
1338 	 */
1339 	if (trans_delay_msecs != 0)
1340 		msleep_interruptible(trans_delay_msecs);
1341 	/*
1342 	 * See if we need to update the ALUA fabric port metadata for
1343 	 * secondary state and status
1344 	 */
1345 	if (port->sep_tg_pt_secondary_write_md) {
1346 		mutex_lock(&port->sep_tg_pt_md_mutex);
1347 		core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port);
1348 		mutex_unlock(&port->sep_tg_pt_md_mutex);
1349 	}
1350 
1351 	return 0;
1352 }
1353 
1354 struct t10_alua_lba_map *
1355 core_alua_allocate_lba_map(struct list_head *list,
1356 			   u64 first_lba, u64 last_lba)
1357 {
1358 	struct t10_alua_lba_map *lba_map;
1359 
1360 	lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1361 	if (!lba_map) {
1362 		pr_err("Unable to allocate struct t10_alua_lba_map\n");
1363 		return ERR_PTR(-ENOMEM);
1364 	}
1365 	INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1366 	lba_map->lba_map_first_lba = first_lba;
1367 	lba_map->lba_map_last_lba = last_lba;
1368 
1369 	list_add_tail(&lba_map->lba_map_list, list);
1370 	return lba_map;
1371 }
1372 
1373 int
1374 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1375 			       int pg_id, int state)
1376 {
1377 	struct t10_alua_lba_map_member *lba_map_mem;
1378 
1379 	list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1380 			    lba_map_mem_list) {
1381 		if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1382 			pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1383 			return -EINVAL;
1384 		}
1385 	}
1386 
1387 	lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1388 	if (!lba_map_mem) {
1389 		pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1390 		return -ENOMEM;
1391 	}
1392 	lba_map_mem->lba_map_mem_alua_state = state;
1393 	lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1394 
1395 	list_add_tail(&lba_map_mem->lba_map_mem_list,
1396 		      &lba_map->lba_map_mem_list);
1397 	return 0;
1398 }
1399 
1400 void
1401 core_alua_free_lba_map(struct list_head *lba_list)
1402 {
1403 	struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1404 	struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1405 
1406 	list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1407 				 lba_map_list) {
1408 		list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1409 					 &lba_map->lba_map_mem_list,
1410 					 lba_map_mem_list) {
1411 			list_del(&lba_map_mem->lba_map_mem_list);
1412 			kmem_cache_free(t10_alua_lba_map_mem_cache,
1413 					lba_map_mem);
1414 		}
1415 		list_del(&lba_map->lba_map_list);
1416 		kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1417 	}
1418 }
1419 
1420 void
1421 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1422 		      int segment_size, int segment_mult)
1423 {
1424 	struct list_head old_lba_map_list;
1425 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1426 	int activate = 0, supported;
1427 
1428 	INIT_LIST_HEAD(&old_lba_map_list);
1429 	spin_lock(&dev->t10_alua.lba_map_lock);
1430 	dev->t10_alua.lba_map_segment_size = segment_size;
1431 	dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1432 	list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1433 	if (lba_map_list) {
1434 		list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1435 		activate = 1;
1436 	}
1437 	spin_unlock(&dev->t10_alua.lba_map_lock);
1438 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1439 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1440 			    tg_pt_gp_list) {
1441 
1442 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1443 			continue;
1444 		supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1445 		if (activate)
1446 			supported |= ALUA_LBD_SUP;
1447 		else
1448 			supported &= ~ALUA_LBD_SUP;
1449 		tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1450 	}
1451 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1452 	core_alua_free_lba_map(&old_lba_map_list);
1453 }
1454 
1455 struct t10_alua_lu_gp *
1456 core_alua_allocate_lu_gp(const char *name, int def_group)
1457 {
1458 	struct t10_alua_lu_gp *lu_gp;
1459 
1460 	lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1461 	if (!lu_gp) {
1462 		pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1463 		return ERR_PTR(-ENOMEM);
1464 	}
1465 	INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1466 	INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1467 	spin_lock_init(&lu_gp->lu_gp_lock);
1468 	atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1469 
1470 	if (def_group) {
1471 		lu_gp->lu_gp_id = alua_lu_gps_counter++;
1472 		lu_gp->lu_gp_valid_id = 1;
1473 		alua_lu_gps_count++;
1474 	}
1475 
1476 	return lu_gp;
1477 }
1478 
1479 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1480 {
1481 	struct t10_alua_lu_gp *lu_gp_tmp;
1482 	u16 lu_gp_id_tmp;
1483 	/*
1484 	 * The lu_gp->lu_gp_id may only be set once..
1485 	 */
1486 	if (lu_gp->lu_gp_valid_id) {
1487 		pr_warn("ALUA LU Group already has a valid ID,"
1488 			" ignoring request\n");
1489 		return -EINVAL;
1490 	}
1491 
1492 	spin_lock(&lu_gps_lock);
1493 	if (alua_lu_gps_count == 0x0000ffff) {
1494 		pr_err("Maximum ALUA alua_lu_gps_count:"
1495 				" 0x0000ffff reached\n");
1496 		spin_unlock(&lu_gps_lock);
1497 		kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1498 		return -ENOSPC;
1499 	}
1500 again:
1501 	lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1502 				alua_lu_gps_counter++;
1503 
1504 	list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1505 		if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1506 			if (!lu_gp_id)
1507 				goto again;
1508 
1509 			pr_warn("ALUA Logical Unit Group ID: %hu"
1510 				" already exists, ignoring request\n",
1511 				lu_gp_id);
1512 			spin_unlock(&lu_gps_lock);
1513 			return -EINVAL;
1514 		}
1515 	}
1516 
1517 	lu_gp->lu_gp_id = lu_gp_id_tmp;
1518 	lu_gp->lu_gp_valid_id = 1;
1519 	list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1520 	alua_lu_gps_count++;
1521 	spin_unlock(&lu_gps_lock);
1522 
1523 	return 0;
1524 }
1525 
1526 static struct t10_alua_lu_gp_member *
1527 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1528 {
1529 	struct t10_alua_lu_gp_member *lu_gp_mem;
1530 
1531 	lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1532 	if (!lu_gp_mem) {
1533 		pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1534 		return ERR_PTR(-ENOMEM);
1535 	}
1536 	INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1537 	spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1538 	atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1539 
1540 	lu_gp_mem->lu_gp_mem_dev = dev;
1541 	dev->dev_alua_lu_gp_mem = lu_gp_mem;
1542 
1543 	return lu_gp_mem;
1544 }
1545 
1546 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1547 {
1548 	struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1549 	/*
1550 	 * Once we have reached this point, config_item_put() has
1551 	 * already been called from target_core_alua_drop_lu_gp().
1552 	 *
1553 	 * Here, we remove the *lu_gp from the global list so that
1554 	 * no associations can be made while we are releasing
1555 	 * struct t10_alua_lu_gp.
1556 	 */
1557 	spin_lock(&lu_gps_lock);
1558 	list_del(&lu_gp->lu_gp_node);
1559 	alua_lu_gps_count--;
1560 	spin_unlock(&lu_gps_lock);
1561 	/*
1562 	 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1563 	 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1564 	 * released with core_alua_put_lu_gp_from_name()
1565 	 */
1566 	while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1567 		cpu_relax();
1568 	/*
1569 	 * Release reference to struct t10_alua_lu_gp * from all associated
1570 	 * struct se_device.
1571 	 */
1572 	spin_lock(&lu_gp->lu_gp_lock);
1573 	list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1574 				&lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1575 		if (lu_gp_mem->lu_gp_assoc) {
1576 			list_del(&lu_gp_mem->lu_gp_mem_list);
1577 			lu_gp->lu_gp_members--;
1578 			lu_gp_mem->lu_gp_assoc = 0;
1579 		}
1580 		spin_unlock(&lu_gp->lu_gp_lock);
1581 		/*
1582 		 *
1583 		 * lu_gp_mem is associated with a single
1584 		 * struct se_device->dev_alua_lu_gp_mem, and is released when
1585 		 * struct se_device is released via core_alua_free_lu_gp_mem().
1586 		 *
1587 		 * If the passed lu_gp does NOT match the default_lu_gp, assume
1588 		 * we want to re-associate a given lu_gp_mem with default_lu_gp.
1589 		 */
1590 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1591 		if (lu_gp != default_lu_gp)
1592 			__core_alua_attach_lu_gp_mem(lu_gp_mem,
1593 					default_lu_gp);
1594 		else
1595 			lu_gp_mem->lu_gp = NULL;
1596 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1597 
1598 		spin_lock(&lu_gp->lu_gp_lock);
1599 	}
1600 	spin_unlock(&lu_gp->lu_gp_lock);
1601 
1602 	kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1603 }
1604 
1605 void core_alua_free_lu_gp_mem(struct se_device *dev)
1606 {
1607 	struct t10_alua_lu_gp *lu_gp;
1608 	struct t10_alua_lu_gp_member *lu_gp_mem;
1609 
1610 	lu_gp_mem = dev->dev_alua_lu_gp_mem;
1611 	if (!lu_gp_mem)
1612 		return;
1613 
1614 	while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1615 		cpu_relax();
1616 
1617 	spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1618 	lu_gp = lu_gp_mem->lu_gp;
1619 	if (lu_gp) {
1620 		spin_lock(&lu_gp->lu_gp_lock);
1621 		if (lu_gp_mem->lu_gp_assoc) {
1622 			list_del(&lu_gp_mem->lu_gp_mem_list);
1623 			lu_gp->lu_gp_members--;
1624 			lu_gp_mem->lu_gp_assoc = 0;
1625 		}
1626 		spin_unlock(&lu_gp->lu_gp_lock);
1627 		lu_gp_mem->lu_gp = NULL;
1628 	}
1629 	spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1630 
1631 	kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1632 }
1633 
1634 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1635 {
1636 	struct t10_alua_lu_gp *lu_gp;
1637 	struct config_item *ci;
1638 
1639 	spin_lock(&lu_gps_lock);
1640 	list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1641 		if (!lu_gp->lu_gp_valid_id)
1642 			continue;
1643 		ci = &lu_gp->lu_gp_group.cg_item;
1644 		if (!strcmp(config_item_name(ci), name)) {
1645 			atomic_inc(&lu_gp->lu_gp_ref_cnt);
1646 			spin_unlock(&lu_gps_lock);
1647 			return lu_gp;
1648 		}
1649 	}
1650 	spin_unlock(&lu_gps_lock);
1651 
1652 	return NULL;
1653 }
1654 
1655 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1656 {
1657 	spin_lock(&lu_gps_lock);
1658 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1659 	spin_unlock(&lu_gps_lock);
1660 }
1661 
1662 /*
1663  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1664  */
1665 void __core_alua_attach_lu_gp_mem(
1666 	struct t10_alua_lu_gp_member *lu_gp_mem,
1667 	struct t10_alua_lu_gp *lu_gp)
1668 {
1669 	spin_lock(&lu_gp->lu_gp_lock);
1670 	lu_gp_mem->lu_gp = lu_gp;
1671 	lu_gp_mem->lu_gp_assoc = 1;
1672 	list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1673 	lu_gp->lu_gp_members++;
1674 	spin_unlock(&lu_gp->lu_gp_lock);
1675 }
1676 
1677 /*
1678  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1679  */
1680 void __core_alua_drop_lu_gp_mem(
1681 	struct t10_alua_lu_gp_member *lu_gp_mem,
1682 	struct t10_alua_lu_gp *lu_gp)
1683 {
1684 	spin_lock(&lu_gp->lu_gp_lock);
1685 	list_del(&lu_gp_mem->lu_gp_mem_list);
1686 	lu_gp_mem->lu_gp = NULL;
1687 	lu_gp_mem->lu_gp_assoc = 0;
1688 	lu_gp->lu_gp_members--;
1689 	spin_unlock(&lu_gp->lu_gp_lock);
1690 }
1691 
1692 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1693 		const char *name, int def_group)
1694 {
1695 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1696 
1697 	tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1698 	if (!tg_pt_gp) {
1699 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1700 		return NULL;
1701 	}
1702 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1703 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1704 	mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1705 	spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1706 	atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1707 	INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1708 			  core_alua_do_transition_tg_pt_work);
1709 	tg_pt_gp->tg_pt_gp_dev = dev;
1710 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1711 		ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1712 	/*
1713 	 * Enable both explicit and implicit ALUA support by default
1714 	 */
1715 	tg_pt_gp->tg_pt_gp_alua_access_type =
1716 			TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1717 	/*
1718 	 * Set the default Active/NonOptimized Delay in milliseconds
1719 	 */
1720 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1721 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1722 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1723 
1724 	/*
1725 	 * Enable all supported states
1726 	 */
1727 	tg_pt_gp->tg_pt_gp_alua_supported_states =
1728 	    ALUA_T_SUP | ALUA_O_SUP |
1729 	    ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1730 
1731 	if (def_group) {
1732 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1733 		tg_pt_gp->tg_pt_gp_id =
1734 				dev->t10_alua.alua_tg_pt_gps_counter++;
1735 		tg_pt_gp->tg_pt_gp_valid_id = 1;
1736 		dev->t10_alua.alua_tg_pt_gps_count++;
1737 		list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1738 			      &dev->t10_alua.tg_pt_gps_list);
1739 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1740 	}
1741 
1742 	return tg_pt_gp;
1743 }
1744 
1745 int core_alua_set_tg_pt_gp_id(
1746 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1747 	u16 tg_pt_gp_id)
1748 {
1749 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1750 	struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1751 	u16 tg_pt_gp_id_tmp;
1752 
1753 	/*
1754 	 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1755 	 */
1756 	if (tg_pt_gp->tg_pt_gp_valid_id) {
1757 		pr_warn("ALUA TG PT Group already has a valid ID,"
1758 			" ignoring request\n");
1759 		return -EINVAL;
1760 	}
1761 
1762 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1763 	if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1764 		pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1765 			" 0x0000ffff reached\n");
1766 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1767 		kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1768 		return -ENOSPC;
1769 	}
1770 again:
1771 	tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1772 			dev->t10_alua.alua_tg_pt_gps_counter++;
1773 
1774 	list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1775 			tg_pt_gp_list) {
1776 		if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1777 			if (!tg_pt_gp_id)
1778 				goto again;
1779 
1780 			pr_err("ALUA Target Port Group ID: %hu already"
1781 				" exists, ignoring request\n", tg_pt_gp_id);
1782 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1783 			return -EINVAL;
1784 		}
1785 	}
1786 
1787 	tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1788 	tg_pt_gp->tg_pt_gp_valid_id = 1;
1789 	list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1790 			&dev->t10_alua.tg_pt_gps_list);
1791 	dev->t10_alua.alua_tg_pt_gps_count++;
1792 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1793 
1794 	return 0;
1795 }
1796 
1797 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1798 	struct se_port *port)
1799 {
1800 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1801 
1802 	tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1803 				GFP_KERNEL);
1804 	if (!tg_pt_gp_mem) {
1805 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1806 		return ERR_PTR(-ENOMEM);
1807 	}
1808 	INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1809 	spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1810 	atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1811 
1812 	tg_pt_gp_mem->tg_pt = port;
1813 	port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1814 
1815 	return tg_pt_gp_mem;
1816 }
1817 
1818 void core_alua_free_tg_pt_gp(
1819 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1820 {
1821 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1822 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1823 
1824 	/*
1825 	 * Once we have reached this point, config_item_put() has already
1826 	 * been called from target_core_alua_drop_tg_pt_gp().
1827 	 *
1828 	 * Here we remove *tg_pt_gp from the global list so that
1829 	 * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1830 	 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1831 	 */
1832 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1833 	list_del(&tg_pt_gp->tg_pt_gp_list);
1834 	dev->t10_alua.alua_tg_pt_gps_counter--;
1835 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1836 
1837 	flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1838 
1839 	/*
1840 	 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1841 	 * core_alua_get_tg_pt_gp_by_name() in
1842 	 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1843 	 * to be released with core_alua_put_tg_pt_gp_from_name().
1844 	 */
1845 	while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1846 		cpu_relax();
1847 
1848 	/*
1849 	 * Release reference to struct t10_alua_tg_pt_gp from all associated
1850 	 * struct se_port.
1851 	 */
1852 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1853 	list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1854 			&tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1855 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1856 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1857 			tg_pt_gp->tg_pt_gp_members--;
1858 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1859 		}
1860 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1861 		/*
1862 		 * tg_pt_gp_mem is associated with a single
1863 		 * se_port->sep_alua_tg_pt_gp_mem, and is released via
1864 		 * core_alua_free_tg_pt_gp_mem().
1865 		 *
1866 		 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1867 		 * assume we want to re-associate a given tg_pt_gp_mem with
1868 		 * default_tg_pt_gp.
1869 		 */
1870 		spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1871 		if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1872 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1873 					dev->t10_alua.default_tg_pt_gp);
1874 		} else
1875 			tg_pt_gp_mem->tg_pt_gp = NULL;
1876 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1877 
1878 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1879 	}
1880 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1881 
1882 	kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1883 }
1884 
1885 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1886 {
1887 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1888 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1889 
1890 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1891 	if (!tg_pt_gp_mem)
1892 		return;
1893 
1894 	while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1895 		cpu_relax();
1896 
1897 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1898 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1899 	if (tg_pt_gp) {
1900 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1901 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1902 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1903 			tg_pt_gp->tg_pt_gp_members--;
1904 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1905 		}
1906 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1907 		tg_pt_gp_mem->tg_pt_gp = NULL;
1908 	}
1909 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1910 
1911 	kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1912 }
1913 
1914 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1915 		struct se_device *dev, const char *name)
1916 {
1917 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1918 	struct config_item *ci;
1919 
1920 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1921 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1922 			tg_pt_gp_list) {
1923 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1924 			continue;
1925 		ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1926 		if (!strcmp(config_item_name(ci), name)) {
1927 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1928 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1929 			return tg_pt_gp;
1930 		}
1931 	}
1932 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1933 
1934 	return NULL;
1935 }
1936 
1937 static void core_alua_put_tg_pt_gp_from_name(
1938 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1939 {
1940 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1941 
1942 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1943 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1944 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1945 }
1946 
1947 /*
1948  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1949  */
1950 void __core_alua_attach_tg_pt_gp_mem(
1951 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1952 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1953 {
1954 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1955 	tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1956 	tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1957 	list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1958 			&tg_pt_gp->tg_pt_gp_mem_list);
1959 	tg_pt_gp->tg_pt_gp_members++;
1960 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1961 }
1962 
1963 /*
1964  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1965  */
1966 static void __core_alua_drop_tg_pt_gp_mem(
1967 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1968 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1969 {
1970 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1971 	list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1972 	tg_pt_gp_mem->tg_pt_gp = NULL;
1973 	tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1974 	tg_pt_gp->tg_pt_gp_members--;
1975 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1976 }
1977 
1978 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1979 {
1980 	struct config_item *tg_pt_ci;
1981 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1982 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1983 	ssize_t len = 0;
1984 
1985 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1986 	if (!tg_pt_gp_mem)
1987 		return len;
1988 
1989 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1990 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1991 	if (tg_pt_gp) {
1992 		tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1993 		len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1994 			" %hu\nTG Port Primary Access State: %s\nTG Port "
1995 			"Primary Access Status: %s\nTG Port Secondary Access"
1996 			" State: %s\nTG Port Secondary Access Status: %s\n",
1997 			config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1998 			core_alua_dump_state(atomic_read(
1999 					&tg_pt_gp->tg_pt_gp_alua_access_state)),
2000 			core_alua_dump_status(
2001 				tg_pt_gp->tg_pt_gp_alua_access_status),
2002 			(atomic_read(&port->sep_tg_pt_secondary_offline)) ?
2003 			"Offline" : "None",
2004 			core_alua_dump_status(port->sep_tg_pt_secondary_stat));
2005 	}
2006 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2007 
2008 	return len;
2009 }
2010 
2011 ssize_t core_alua_store_tg_pt_gp_info(
2012 	struct se_port *port,
2013 	const char *page,
2014 	size_t count)
2015 {
2016 	struct se_portal_group *tpg;
2017 	struct se_lun *lun;
2018 	struct se_device *dev = port->sep_lun->lun_se_dev;
2019 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
2020 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2021 	unsigned char buf[TG_PT_GROUP_NAME_BUF];
2022 	int move = 0;
2023 
2024 	tpg = port->sep_tpg;
2025 	lun = port->sep_lun;
2026 
2027 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
2028 	if (!tg_pt_gp_mem)
2029 		return 0;
2030 
2031 	if (count > TG_PT_GROUP_NAME_BUF) {
2032 		pr_err("ALUA Target Port Group alias too large!\n");
2033 		return -EINVAL;
2034 	}
2035 	memset(buf, 0, TG_PT_GROUP_NAME_BUF);
2036 	memcpy(buf, page, count);
2037 	/*
2038 	 * Any ALUA target port group alias besides "NULL" means we will be
2039 	 * making a new group association.
2040 	 */
2041 	if (strcmp(strstrip(buf), "NULL")) {
2042 		/*
2043 		 * core_alua_get_tg_pt_gp_by_name() will increment reference to
2044 		 * struct t10_alua_tg_pt_gp.  This reference is released with
2045 		 * core_alua_put_tg_pt_gp_from_name() below.
2046 		 */
2047 		tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
2048 					strstrip(buf));
2049 		if (!tg_pt_gp_new)
2050 			return -ENODEV;
2051 	}
2052 
2053 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2054 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
2055 	if (tg_pt_gp) {
2056 		/*
2057 		 * Clearing an existing tg_pt_gp association, and replacing
2058 		 * with the default_tg_pt_gp.
2059 		 */
2060 		if (!tg_pt_gp_new) {
2061 			pr_debug("Target_Core_ConfigFS: Moving"
2062 				" %s/tpgt_%hu/%s from ALUA Target Port Group:"
2063 				" alua/%s, ID: %hu back to"
2064 				" default_tg_pt_gp\n",
2065 				tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2066 				tpg->se_tpg_tfo->tpg_get_tag(tpg),
2067 				config_item_name(&lun->lun_group.cg_item),
2068 				config_item_name(
2069 					&tg_pt_gp->tg_pt_gp_group.cg_item),
2070 				tg_pt_gp->tg_pt_gp_id);
2071 
2072 			__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2073 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
2074 					dev->t10_alua.default_tg_pt_gp);
2075 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2076 
2077 			return count;
2078 		}
2079 		/*
2080 		 * Removing existing association of tg_pt_gp_mem with tg_pt_gp
2081 		 */
2082 		__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2083 		move = 1;
2084 	}
2085 	/*
2086 	 * Associate tg_pt_gp_mem with tg_pt_gp_new.
2087 	 */
2088 	__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
2089 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2090 	pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2091 		" Target Port Group: alua/%s, ID: %hu\n", (move) ?
2092 		"Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2093 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
2094 		config_item_name(&lun->lun_group.cg_item),
2095 		config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2096 		tg_pt_gp_new->tg_pt_gp_id);
2097 
2098 	core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2099 	return count;
2100 }
2101 
2102 ssize_t core_alua_show_access_type(
2103 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2104 	char *page)
2105 {
2106 	if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2107 	    (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2108 		return sprintf(page, "Implicit and Explicit\n");
2109 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2110 		return sprintf(page, "Implicit\n");
2111 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2112 		return sprintf(page, "Explicit\n");
2113 	else
2114 		return sprintf(page, "None\n");
2115 }
2116 
2117 ssize_t core_alua_store_access_type(
2118 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2119 	const char *page,
2120 	size_t count)
2121 {
2122 	unsigned long tmp;
2123 	int ret;
2124 
2125 	ret = kstrtoul(page, 0, &tmp);
2126 	if (ret < 0) {
2127 		pr_err("Unable to extract alua_access_type\n");
2128 		return ret;
2129 	}
2130 	if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2131 		pr_err("Illegal value for alua_access_type:"
2132 				" %lu\n", tmp);
2133 		return -EINVAL;
2134 	}
2135 	if (tmp == 3)
2136 		tg_pt_gp->tg_pt_gp_alua_access_type =
2137 			TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2138 	else if (tmp == 2)
2139 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2140 	else if (tmp == 1)
2141 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2142 	else
2143 		tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2144 
2145 	return count;
2146 }
2147 
2148 ssize_t core_alua_show_nonop_delay_msecs(
2149 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2150 	char *page)
2151 {
2152 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2153 }
2154 
2155 ssize_t core_alua_store_nonop_delay_msecs(
2156 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2157 	const char *page,
2158 	size_t count)
2159 {
2160 	unsigned long tmp;
2161 	int ret;
2162 
2163 	ret = kstrtoul(page, 0, &tmp);
2164 	if (ret < 0) {
2165 		pr_err("Unable to extract nonop_delay_msecs\n");
2166 		return ret;
2167 	}
2168 	if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2169 		pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2170 			" ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2171 			ALUA_MAX_NONOP_DELAY_MSECS);
2172 		return -EINVAL;
2173 	}
2174 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2175 
2176 	return count;
2177 }
2178 
2179 ssize_t core_alua_show_trans_delay_msecs(
2180 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2181 	char *page)
2182 {
2183 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2184 }
2185 
2186 ssize_t core_alua_store_trans_delay_msecs(
2187 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2188 	const char *page,
2189 	size_t count)
2190 {
2191 	unsigned long tmp;
2192 	int ret;
2193 
2194 	ret = kstrtoul(page, 0, &tmp);
2195 	if (ret < 0) {
2196 		pr_err("Unable to extract trans_delay_msecs\n");
2197 		return ret;
2198 	}
2199 	if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2200 		pr_err("Passed trans_delay_msecs: %lu, exceeds"
2201 			" ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2202 			ALUA_MAX_TRANS_DELAY_MSECS);
2203 		return -EINVAL;
2204 	}
2205 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2206 
2207 	return count;
2208 }
2209 
2210 ssize_t core_alua_show_implicit_trans_secs(
2211 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2212 	char *page)
2213 {
2214 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2215 }
2216 
2217 ssize_t core_alua_store_implicit_trans_secs(
2218 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2219 	const char *page,
2220 	size_t count)
2221 {
2222 	unsigned long tmp;
2223 	int ret;
2224 
2225 	ret = kstrtoul(page, 0, &tmp);
2226 	if (ret < 0) {
2227 		pr_err("Unable to extract implicit_trans_secs\n");
2228 		return ret;
2229 	}
2230 	if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2231 		pr_err("Passed implicit_trans_secs: %lu, exceeds"
2232 			" ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2233 			ALUA_MAX_IMPLICIT_TRANS_SECS);
2234 		return  -EINVAL;
2235 	}
2236 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2237 
2238 	return count;
2239 }
2240 
2241 ssize_t core_alua_show_preferred_bit(
2242 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2243 	char *page)
2244 {
2245 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2246 }
2247 
2248 ssize_t core_alua_store_preferred_bit(
2249 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2250 	const char *page,
2251 	size_t count)
2252 {
2253 	unsigned long tmp;
2254 	int ret;
2255 
2256 	ret = kstrtoul(page, 0, &tmp);
2257 	if (ret < 0) {
2258 		pr_err("Unable to extract preferred ALUA value\n");
2259 		return ret;
2260 	}
2261 	if ((tmp != 0) && (tmp != 1)) {
2262 		pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2263 		return -EINVAL;
2264 	}
2265 	tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2266 
2267 	return count;
2268 }
2269 
2270 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2271 {
2272 	if (!lun->lun_sep)
2273 		return -ENODEV;
2274 
2275 	return sprintf(page, "%d\n",
2276 		atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
2277 }
2278 
2279 ssize_t core_alua_store_offline_bit(
2280 	struct se_lun *lun,
2281 	const char *page,
2282 	size_t count)
2283 {
2284 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2285 	unsigned long tmp;
2286 	int ret;
2287 
2288 	if (!lun->lun_sep)
2289 		return -ENODEV;
2290 
2291 	ret = kstrtoul(page, 0, &tmp);
2292 	if (ret < 0) {
2293 		pr_err("Unable to extract alua_tg_pt_offline value\n");
2294 		return ret;
2295 	}
2296 	if ((tmp != 0) && (tmp != 1)) {
2297 		pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2298 				tmp);
2299 		return -EINVAL;
2300 	}
2301 	tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
2302 	if (!tg_pt_gp_mem) {
2303 		pr_err("Unable to locate *tg_pt_gp_mem\n");
2304 		return -EINVAL;
2305 	}
2306 
2307 	ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
2308 			lun->lun_sep, 0, (int)tmp);
2309 	if (ret < 0)
2310 		return -EINVAL;
2311 
2312 	return count;
2313 }
2314 
2315 ssize_t core_alua_show_secondary_status(
2316 	struct se_lun *lun,
2317 	char *page)
2318 {
2319 	return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
2320 }
2321 
2322 ssize_t core_alua_store_secondary_status(
2323 	struct se_lun *lun,
2324 	const char *page,
2325 	size_t count)
2326 {
2327 	unsigned long tmp;
2328 	int ret;
2329 
2330 	ret = kstrtoul(page, 0, &tmp);
2331 	if (ret < 0) {
2332 		pr_err("Unable to extract alua_tg_pt_status\n");
2333 		return ret;
2334 	}
2335 	if ((tmp != ALUA_STATUS_NONE) &&
2336 	    (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2337 	    (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2338 		pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2339 				tmp);
2340 		return -EINVAL;
2341 	}
2342 	lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
2343 
2344 	return count;
2345 }
2346 
2347 ssize_t core_alua_show_secondary_write_metadata(
2348 	struct se_lun *lun,
2349 	char *page)
2350 {
2351 	return sprintf(page, "%d\n",
2352 			lun->lun_sep->sep_tg_pt_secondary_write_md);
2353 }
2354 
2355 ssize_t core_alua_store_secondary_write_metadata(
2356 	struct se_lun *lun,
2357 	const char *page,
2358 	size_t count)
2359 {
2360 	unsigned long tmp;
2361 	int ret;
2362 
2363 	ret = kstrtoul(page, 0, &tmp);
2364 	if (ret < 0) {
2365 		pr_err("Unable to extract alua_tg_pt_write_md\n");
2366 		return ret;
2367 	}
2368 	if ((tmp != 0) && (tmp != 1)) {
2369 		pr_err("Illegal value for alua_tg_pt_write_md:"
2370 				" %lu\n", tmp);
2371 		return -EINVAL;
2372 	}
2373 	lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
2374 
2375 	return count;
2376 }
2377 
2378 int core_setup_alua(struct se_device *dev)
2379 {
2380 	if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV &&
2381 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2382 		struct t10_alua_lu_gp_member *lu_gp_mem;
2383 
2384 		/*
2385 		 * Associate this struct se_device with the default ALUA
2386 		 * LUN Group.
2387 		 */
2388 		lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2389 		if (IS_ERR(lu_gp_mem))
2390 			return PTR_ERR(lu_gp_mem);
2391 
2392 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2393 		__core_alua_attach_lu_gp_mem(lu_gp_mem,
2394 				default_lu_gp);
2395 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2396 
2397 		pr_debug("%s: Adding to default ALUA LU Group:"
2398 			" core/alua/lu_gps/default_lu_gp\n",
2399 			dev->transport->name);
2400 	}
2401 
2402 	return 0;
2403 }
2404