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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 
38 #include "target_core_internal.h"
39 #include "target_core_alua.h"
40 #include "target_core_ua.h"
41 
42 static sense_reason_t core_alua_check_transition(int state, int valid,
43 						 int *primary);
44 static int core_alua_set_tg_pt_secondary_state(
45 		struct se_lun *lun, int explicit, int offline);
46 
47 static char *core_alua_dump_state(int state);
48 
49 static void __target_attach_tg_pt_gp(struct se_lun *lun,
50 		struct t10_alua_tg_pt_gp *tg_pt_gp);
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
target_emulate_report_referrals(struct se_cmd * cmd)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
target_emulate_report_target_port_groups(struct se_cmd * cmd)146 target_emulate_report_target_port_groups(struct se_cmd *cmd)
147 {
148 	struct se_device *dev = cmd->se_dev;
149 	struct t10_alua_tg_pt_gp *tg_pt_gp;
150 	struct se_lun *lun;
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(lun, &tg_pt_gp->tg_pt_gp_lun_list,
226 				lun_tg_pt_gp_link) {
227 			/*
228 			 * Start Target Port descriptor format
229 			 *
230 			 * See spc4r17 section 6.2.7 Table 247
231 			 */
232 			off += 2; /* Skip over Obsolete */
233 			/*
234 			 * Set RELATIVE TARGET PORT IDENTIFIER
235 			 */
236 			buf[off++] = ((lun->lun_rtpi >> 8) & 0xff);
237 			buf[off++] = (lun->lun_rtpi & 0xff);
238 			rd_len += 4;
239 		}
240 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
241 	}
242 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
243 	/*
244 	 * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
245 	 */
246 	put_unaligned_be32(rd_len, &buf[0]);
247 
248 	/*
249 	 * Fill in the Extended header parameter data format if requested
250 	 */
251 	if (ext_hdr != 0) {
252 		buf[4] = 0x10;
253 		/*
254 		 * Set the implicit transition time (in seconds) for the application
255 		 * client to use as a base for it's transition timeout value.
256 		 *
257 		 * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
258 		 * this CDB was received upon to determine this value individually
259 		 * for ALUA target port group.
260 		 */
261 		spin_lock(&cmd->se_lun->lun_tg_pt_gp_lock);
262 		tg_pt_gp = cmd->se_lun->lun_tg_pt_gp;
263 		if (tg_pt_gp)
264 			buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
265 		spin_unlock(&cmd->se_lun->lun_tg_pt_gp_lock);
266 	}
267 	transport_kunmap_data_sg(cmd);
268 
269 	target_complete_cmd(cmd, GOOD);
270 	return 0;
271 }
272 
273 /*
274  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
275  *
276  * See spc4r17 section 6.35
277  */
278 sense_reason_t
target_emulate_set_target_port_groups(struct se_cmd * cmd)279 target_emulate_set_target_port_groups(struct se_cmd *cmd)
280 {
281 	struct se_device *dev = cmd->se_dev;
282 	struct se_lun *l_lun = cmd->se_lun;
283 	struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
284 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
285 	unsigned char *buf;
286 	unsigned char *ptr;
287 	sense_reason_t rc = TCM_NO_SENSE;
288 	u32 len = 4; /* Skip over RESERVED area in header */
289 	int alua_access_state, primary = 0, valid_states;
290 	u16 tg_pt_id, rtpi;
291 
292 	if (cmd->data_length < 4) {
293 		pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
294 			" small\n", cmd->data_length);
295 		return TCM_INVALID_PARAMETER_LIST;
296 	}
297 
298 	buf = transport_kmap_data_sg(cmd);
299 	if (!buf)
300 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
301 
302 	/*
303 	 * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
304 	 * for the local tg_pt_gp.
305 	 */
306 	spin_lock(&l_lun->lun_tg_pt_gp_lock);
307 	l_tg_pt_gp = l_lun->lun_tg_pt_gp;
308 	if (!l_tg_pt_gp) {
309 		spin_unlock(&l_lun->lun_tg_pt_gp_lock);
310 		pr_err("Unable to access l_lun->tg_pt_gp\n");
311 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
312 		goto out;
313 	}
314 
315 	if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
316 		spin_unlock(&l_lun->lun_tg_pt_gp_lock);
317 		pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
318 				" while TPGS_EXPLICIT_ALUA is disabled\n");
319 		rc = TCM_UNSUPPORTED_SCSI_OPCODE;
320 		goto out;
321 	}
322 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
323 	spin_unlock(&l_lun->lun_tg_pt_gp_lock);
324 
325 	ptr = &buf[4]; /* Skip over RESERVED area in header */
326 
327 	while (len < cmd->data_length) {
328 		bool found = false;
329 		alua_access_state = (ptr[0] & 0x0f);
330 		/*
331 		 * Check the received ALUA access state, and determine if
332 		 * the state is a primary or secondary target port asymmetric
333 		 * access state.
334 		 */
335 		rc = core_alua_check_transition(alua_access_state,
336 						valid_states, &primary);
337 		if (rc) {
338 			/*
339 			 * If the SET TARGET PORT GROUPS attempts to establish
340 			 * an invalid combination of target port asymmetric
341 			 * access states or attempts to establish an
342 			 * unsupported target port asymmetric access state,
343 			 * then the command shall be terminated with CHECK
344 			 * CONDITION status, with the sense key set to ILLEGAL
345 			 * REQUEST, and the additional sense code set to INVALID
346 			 * FIELD IN PARAMETER LIST.
347 			 */
348 			goto out;
349 		}
350 
351 		/*
352 		 * If the ASYMMETRIC ACCESS STATE field (see table 267)
353 		 * specifies a primary target port asymmetric access state,
354 		 * then the TARGET PORT GROUP OR TARGET PORT field specifies
355 		 * a primary target port group for which the primary target
356 		 * port asymmetric access state shall be changed. If the
357 		 * ASYMMETRIC ACCESS STATE field specifies a secondary target
358 		 * port asymmetric access state, then the TARGET PORT GROUP OR
359 		 * TARGET PORT field specifies the relative target port
360 		 * identifier (see 3.1.120) of the target port for which the
361 		 * secondary target port asymmetric access state shall be
362 		 * changed.
363 		 */
364 		if (primary) {
365 			tg_pt_id = get_unaligned_be16(ptr + 2);
366 			/*
367 			 * Locate the matching target port group ID from
368 			 * the global tg_pt_gp list
369 			 */
370 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
371 			list_for_each_entry(tg_pt_gp,
372 					&dev->t10_alua.tg_pt_gps_list,
373 					tg_pt_gp_list) {
374 				if (!tg_pt_gp->tg_pt_gp_valid_id)
375 					continue;
376 
377 				if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
378 					continue;
379 
380 				atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
381 
382 				spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
383 
384 				if (!core_alua_do_port_transition(tg_pt_gp,
385 						dev, l_lun, nacl,
386 						alua_access_state, 1))
387 					found = true;
388 
389 				spin_lock(&dev->t10_alua.tg_pt_gps_lock);
390 				atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
391 				break;
392 			}
393 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
394 		} else {
395 			struct se_lun *lun;
396 
397 			/*
398 			 * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
399 			 * the Target Port in question for the the incoming
400 			 * SET_TARGET_PORT_GROUPS op.
401 			 */
402 			rtpi = get_unaligned_be16(ptr + 2);
403 			/*
404 			 * Locate the matching relative target port identifier
405 			 * for the struct se_device storage object.
406 			 */
407 			spin_lock(&dev->se_port_lock);
408 			list_for_each_entry(lun, &dev->dev_sep_list,
409 							lun_dev_link) {
410 				if (lun->lun_rtpi != rtpi)
411 					continue;
412 
413 				// XXX: racy unlock
414 				spin_unlock(&dev->se_port_lock);
415 
416 				if (!core_alua_set_tg_pt_secondary_state(
417 						lun, 1, 1))
418 					found = true;
419 
420 				spin_lock(&dev->se_port_lock);
421 				break;
422 			}
423 			spin_unlock(&dev->se_port_lock);
424 		}
425 
426 		if (!found) {
427 			rc = TCM_INVALID_PARAMETER_LIST;
428 			goto out;
429 		}
430 
431 		ptr += 4;
432 		len += 4;
433 	}
434 
435 out:
436 	transport_kunmap_data_sg(cmd);
437 	if (!rc)
438 		target_complete_cmd(cmd, GOOD);
439 	return rc;
440 }
441 
set_ascq(struct se_cmd * cmd,u8 alua_ascq)442 static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq)
443 {
444 	/*
445 	 * Set SCSI additional sense code (ASC) to 'LUN Not Accessible';
446 	 * The ALUA additional sense code qualifier (ASCQ) is determined
447 	 * by the ALUA primary or secondary access state..
448 	 */
449 	pr_debug("[%s]: ALUA TG Port not available, "
450 		"SenseKey: NOT_READY, ASC/ASCQ: "
451 		"0x04/0x%02x\n",
452 		cmd->se_tfo->get_fabric_name(), alua_ascq);
453 
454 	cmd->scsi_asc = 0x04;
455 	cmd->scsi_ascq = alua_ascq;
456 }
457 
core_alua_state_nonoptimized(struct se_cmd * cmd,unsigned char * cdb,int nonop_delay_msecs)458 static inline void core_alua_state_nonoptimized(
459 	struct se_cmd *cmd,
460 	unsigned char *cdb,
461 	int nonop_delay_msecs)
462 {
463 	/*
464 	 * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
465 	 * later to determine if processing of this cmd needs to be
466 	 * temporarily delayed for the Active/NonOptimized primary access state.
467 	 */
468 	cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
469 	cmd->alua_nonop_delay = nonop_delay_msecs;
470 }
471 
core_alua_state_lba_dependent(struct se_cmd * cmd,struct t10_alua_tg_pt_gp * tg_pt_gp)472 static inline int core_alua_state_lba_dependent(
473 	struct se_cmd *cmd,
474 	struct t10_alua_tg_pt_gp *tg_pt_gp)
475 {
476 	struct se_device *dev = cmd->se_dev;
477 	u64 segment_size, segment_mult, sectors, lba;
478 
479 	/* Only need to check for cdb actually containing LBAs */
480 	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
481 		return 0;
482 
483 	spin_lock(&dev->t10_alua.lba_map_lock);
484 	segment_size = dev->t10_alua.lba_map_segment_size;
485 	segment_mult = dev->t10_alua.lba_map_segment_multiplier;
486 	sectors = cmd->data_length / dev->dev_attrib.block_size;
487 
488 	lba = cmd->t_task_lba;
489 	while (lba < cmd->t_task_lba + sectors) {
490 		struct t10_alua_lba_map *cur_map = NULL, *map;
491 		struct t10_alua_lba_map_member *map_mem;
492 
493 		list_for_each_entry(map, &dev->t10_alua.lba_map_list,
494 				    lba_map_list) {
495 			u64 start_lba, last_lba;
496 			u64 first_lba = map->lba_map_first_lba;
497 
498 			if (segment_mult) {
499 				u64 tmp = lba;
500 				start_lba = do_div(tmp, segment_size * segment_mult);
501 
502 				last_lba = first_lba + segment_size - 1;
503 				if (start_lba >= first_lba &&
504 				    start_lba <= last_lba) {
505 					lba += segment_size;
506 					cur_map = map;
507 					break;
508 				}
509 			} else {
510 				last_lba = map->lba_map_last_lba;
511 				if (lba >= first_lba && lba <= last_lba) {
512 					lba = last_lba + 1;
513 					cur_map = map;
514 					break;
515 				}
516 			}
517 		}
518 		if (!cur_map) {
519 			spin_unlock(&dev->t10_alua.lba_map_lock);
520 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
521 			return 1;
522 		}
523 		list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
524 				    lba_map_mem_list) {
525 			if (map_mem->lba_map_mem_alua_pg_id !=
526 			    tg_pt_gp->tg_pt_gp_id)
527 				continue;
528 			switch(map_mem->lba_map_mem_alua_state) {
529 			case ALUA_ACCESS_STATE_STANDBY:
530 				spin_unlock(&dev->t10_alua.lba_map_lock);
531 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
532 				return 1;
533 			case ALUA_ACCESS_STATE_UNAVAILABLE:
534 				spin_unlock(&dev->t10_alua.lba_map_lock);
535 				set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
536 				return 1;
537 			default:
538 				break;
539 			}
540 		}
541 	}
542 	spin_unlock(&dev->t10_alua.lba_map_lock);
543 	return 0;
544 }
545 
core_alua_state_standby(struct se_cmd * cmd,unsigned char * cdb)546 static inline int core_alua_state_standby(
547 	struct se_cmd *cmd,
548 	unsigned char *cdb)
549 {
550 	/*
551 	 * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
552 	 * spc4r17 section 5.9.2.4.4
553 	 */
554 	switch (cdb[0]) {
555 	case INQUIRY:
556 	case LOG_SELECT:
557 	case LOG_SENSE:
558 	case MODE_SELECT:
559 	case MODE_SENSE:
560 	case REPORT_LUNS:
561 	case RECEIVE_DIAGNOSTIC:
562 	case SEND_DIAGNOSTIC:
563 	case READ_CAPACITY:
564 		return 0;
565 	case SERVICE_ACTION_IN_16:
566 		switch (cdb[1] & 0x1f) {
567 		case SAI_READ_CAPACITY_16:
568 			return 0;
569 		default:
570 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
571 			return 1;
572 		}
573 	case MAINTENANCE_IN:
574 		switch (cdb[1] & 0x1f) {
575 		case MI_REPORT_TARGET_PGS:
576 			return 0;
577 		default:
578 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
579 			return 1;
580 		}
581 	case MAINTENANCE_OUT:
582 		switch (cdb[1]) {
583 		case MO_SET_TARGET_PGS:
584 			return 0;
585 		default:
586 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
587 			return 1;
588 		}
589 	case REQUEST_SENSE:
590 	case PERSISTENT_RESERVE_IN:
591 	case PERSISTENT_RESERVE_OUT:
592 	case READ_BUFFER:
593 	case WRITE_BUFFER:
594 		return 0;
595 	default:
596 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY);
597 		return 1;
598 	}
599 
600 	return 0;
601 }
602 
core_alua_state_unavailable(struct se_cmd * cmd,unsigned char * cdb)603 static inline int core_alua_state_unavailable(
604 	struct se_cmd *cmd,
605 	unsigned char *cdb)
606 {
607 	/*
608 	 * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
609 	 * spc4r17 section 5.9.2.4.5
610 	 */
611 	switch (cdb[0]) {
612 	case INQUIRY:
613 	case REPORT_LUNS:
614 		return 0;
615 	case MAINTENANCE_IN:
616 		switch (cdb[1] & 0x1f) {
617 		case MI_REPORT_TARGET_PGS:
618 			return 0;
619 		default:
620 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
621 			return 1;
622 		}
623 	case MAINTENANCE_OUT:
624 		switch (cdb[1]) {
625 		case MO_SET_TARGET_PGS:
626 			return 0;
627 		default:
628 			set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
629 			return 1;
630 		}
631 	case REQUEST_SENSE:
632 	case READ_BUFFER:
633 	case WRITE_BUFFER:
634 		return 0;
635 	default:
636 		set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE);
637 		return 1;
638 	}
639 
640 	return 0;
641 }
642 
core_alua_state_transition(struct se_cmd * cmd,unsigned char * cdb)643 static inline int core_alua_state_transition(
644 	struct se_cmd *cmd,
645 	unsigned char *cdb)
646 {
647 	/*
648 	 * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
649 	 * spc4r17 section 5.9.2.5
650 	 */
651 	switch (cdb[0]) {
652 	case INQUIRY:
653 	case REPORT_LUNS:
654 		return 0;
655 	case MAINTENANCE_IN:
656 		switch (cdb[1] & 0x1f) {
657 		case MI_REPORT_TARGET_PGS:
658 			return 0;
659 		default:
660 			set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
661 			return 1;
662 		}
663 	case REQUEST_SENSE:
664 	case READ_BUFFER:
665 	case WRITE_BUFFER:
666 		return 0;
667 	default:
668 		set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION);
669 		return 1;
670 	}
671 
672 	return 0;
673 }
674 
675 /*
676  * return 1: Is used to signal LUN not accessible, and check condition/not ready
677  * return 0: Used to signal success
678  * return -1: Used to signal failure, and invalid cdb field
679  */
680 sense_reason_t
target_alua_state_check(struct se_cmd * cmd)681 target_alua_state_check(struct se_cmd *cmd)
682 {
683 	struct se_device *dev = cmd->se_dev;
684 	unsigned char *cdb = cmd->t_task_cdb;
685 	struct se_lun *lun = cmd->se_lun;
686 	struct t10_alua_tg_pt_gp *tg_pt_gp;
687 	int out_alua_state, nonop_delay_msecs;
688 
689 	if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
690 		return 0;
691 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH)
692 		return 0;
693 
694 	/*
695 	 * First, check for a struct se_port specific secondary ALUA target port
696 	 * access state: OFFLINE
697 	 */
698 	if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
699 		pr_debug("ALUA: Got secondary offline status for local"
700 				" target port\n");
701 		set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE);
702 		return TCM_CHECK_CONDITION_NOT_READY;
703 	}
704 
705 	if (!lun->lun_tg_pt_gp)
706 		return 0;
707 
708 	spin_lock(&lun->lun_tg_pt_gp_lock);
709 	tg_pt_gp = lun->lun_tg_pt_gp;
710 	out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
711 	nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
712 
713 	// XXX: keeps using tg_pt_gp witout reference after unlock
714 	spin_unlock(&lun->lun_tg_pt_gp_lock);
715 	/*
716 	 * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
717 	 * statement so the compiler knows explicitly to check this case first.
718 	 * For the Optimized ALUA access state case, we want to process the
719 	 * incoming fabric cmd ASAP..
720 	 */
721 	if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
722 		return 0;
723 
724 	switch (out_alua_state) {
725 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
726 		core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
727 		break;
728 	case ALUA_ACCESS_STATE_STANDBY:
729 		if (core_alua_state_standby(cmd, cdb))
730 			return TCM_CHECK_CONDITION_NOT_READY;
731 		break;
732 	case ALUA_ACCESS_STATE_UNAVAILABLE:
733 		if (core_alua_state_unavailable(cmd, cdb))
734 			return TCM_CHECK_CONDITION_NOT_READY;
735 		break;
736 	case ALUA_ACCESS_STATE_TRANSITION:
737 		if (core_alua_state_transition(cmd, cdb))
738 			return TCM_CHECK_CONDITION_NOT_READY;
739 		break;
740 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
741 		if (core_alua_state_lba_dependent(cmd, tg_pt_gp))
742 			return TCM_CHECK_CONDITION_NOT_READY;
743 		break;
744 	/*
745 	 * OFFLINE is a secondary ALUA target port group access state, that is
746 	 * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
747 	 */
748 	case ALUA_ACCESS_STATE_OFFLINE:
749 	default:
750 		pr_err("Unknown ALUA access state: 0x%02x\n",
751 				out_alua_state);
752 		return TCM_INVALID_CDB_FIELD;
753 	}
754 
755 	return 0;
756 }
757 
758 /*
759  * Check implicit and explicit ALUA state change request.
760  */
761 static sense_reason_t
core_alua_check_transition(int state,int valid,int * primary)762 core_alua_check_transition(int state, int valid, int *primary)
763 {
764 	/*
765 	 * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
766 	 * defined as primary target port asymmetric access states.
767 	 */
768 	switch (state) {
769 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
770 		if (!(valid & ALUA_AO_SUP))
771 			goto not_supported;
772 		*primary = 1;
773 		break;
774 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
775 		if (!(valid & ALUA_AN_SUP))
776 			goto not_supported;
777 		*primary = 1;
778 		break;
779 	case ALUA_ACCESS_STATE_STANDBY:
780 		if (!(valid & ALUA_S_SUP))
781 			goto not_supported;
782 		*primary = 1;
783 		break;
784 	case ALUA_ACCESS_STATE_UNAVAILABLE:
785 		if (!(valid & ALUA_U_SUP))
786 			goto not_supported;
787 		*primary = 1;
788 		break;
789 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
790 		if (!(valid & ALUA_LBD_SUP))
791 			goto not_supported;
792 		*primary = 1;
793 		break;
794 	case ALUA_ACCESS_STATE_OFFLINE:
795 		/*
796 		 * OFFLINE state is defined as a secondary target port
797 		 * asymmetric access state.
798 		 */
799 		if (!(valid & ALUA_O_SUP))
800 			goto not_supported;
801 		*primary = 0;
802 		break;
803 	case ALUA_ACCESS_STATE_TRANSITION:
804 		/*
805 		 * Transitioning is set internally, and
806 		 * cannot be selected manually.
807 		 */
808 		goto not_supported;
809 	default:
810 		pr_err("Unknown ALUA access state: 0x%02x\n", state);
811 		return TCM_INVALID_PARAMETER_LIST;
812 	}
813 
814 	return 0;
815 
816 not_supported:
817 	pr_err("ALUA access state %s not supported",
818 	       core_alua_dump_state(state));
819 	return TCM_INVALID_PARAMETER_LIST;
820 }
821 
core_alua_dump_state(int state)822 static char *core_alua_dump_state(int state)
823 {
824 	switch (state) {
825 	case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
826 		return "Active/Optimized";
827 	case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
828 		return "Active/NonOptimized";
829 	case ALUA_ACCESS_STATE_LBA_DEPENDENT:
830 		return "LBA Dependent";
831 	case ALUA_ACCESS_STATE_STANDBY:
832 		return "Standby";
833 	case ALUA_ACCESS_STATE_UNAVAILABLE:
834 		return "Unavailable";
835 	case ALUA_ACCESS_STATE_OFFLINE:
836 		return "Offline";
837 	case ALUA_ACCESS_STATE_TRANSITION:
838 		return "Transitioning";
839 	default:
840 		return "Unknown";
841 	}
842 
843 	return NULL;
844 }
845 
core_alua_dump_status(int status)846 char *core_alua_dump_status(int status)
847 {
848 	switch (status) {
849 	case ALUA_STATUS_NONE:
850 		return "None";
851 	case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
852 		return "Altered by Explicit STPG";
853 	case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
854 		return "Altered by Implicit ALUA";
855 	default:
856 		return "Unknown";
857 	}
858 
859 	return NULL;
860 }
861 
862 /*
863  * Used by fabric modules to determine when we need to delay processing
864  * for the Active/NonOptimized paths..
865  */
core_alua_check_nonop_delay(struct se_cmd * cmd)866 int core_alua_check_nonop_delay(
867 	struct se_cmd *cmd)
868 {
869 	if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
870 		return 0;
871 	if (in_interrupt())
872 		return 0;
873 	/*
874 	 * The ALUA Active/NonOptimized access state delay can be disabled
875 	 * in via configfs with a value of zero
876 	 */
877 	if (!cmd->alua_nonop_delay)
878 		return 0;
879 	/*
880 	 * struct se_cmd->alua_nonop_delay gets set by a target port group
881 	 * defined interval in core_alua_state_nonoptimized()
882 	 */
883 	msleep_interruptible(cmd->alua_nonop_delay);
884 	return 0;
885 }
886 EXPORT_SYMBOL(core_alua_check_nonop_delay);
887 
core_alua_write_tpg_metadata(const char * path,unsigned char * md_buf,u32 md_buf_len)888 static int core_alua_write_tpg_metadata(
889 	const char *path,
890 	unsigned char *md_buf,
891 	u32 md_buf_len)
892 {
893 	struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
894 	int ret;
895 
896 	if (IS_ERR(file)) {
897 		pr_err("filp_open(%s) for ALUA metadata failed\n", path);
898 		return -ENODEV;
899 	}
900 	ret = kernel_write(file, md_buf, md_buf_len, 0);
901 	if (ret < 0)
902 		pr_err("Error writing ALUA metadata file: %s\n", path);
903 	fput(file);
904 	return (ret < 0) ? -EIO : 0;
905 }
906 
907 /*
908  * Called with tg_pt_gp->tg_pt_gp_md_mutex held
909  */
core_alua_update_tpg_primary_metadata(struct t10_alua_tg_pt_gp * tg_pt_gp)910 static int core_alua_update_tpg_primary_metadata(
911 	struct t10_alua_tg_pt_gp *tg_pt_gp)
912 {
913 	unsigned char *md_buf;
914 	struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
915 	char path[ALUA_METADATA_PATH_LEN];
916 	int len, rc;
917 
918 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
919 	if (!md_buf) {
920 		pr_err("Unable to allocate buf for ALUA metadata\n");
921 		return -ENOMEM;
922 	}
923 
924 	memset(path, 0, ALUA_METADATA_PATH_LEN);
925 
926 	len = snprintf(md_buf, ALUA_MD_BUF_LEN,
927 			"tg_pt_gp_id=%hu\n"
928 			"alua_access_state=0x%02x\n"
929 			"alua_access_status=0x%02x\n",
930 			tg_pt_gp->tg_pt_gp_id,
931 			tg_pt_gp->tg_pt_gp_alua_pending_state,
932 			tg_pt_gp->tg_pt_gp_alua_access_status);
933 
934 	snprintf(path, ALUA_METADATA_PATH_LEN,
935 		"/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
936 		config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
937 
938 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
939 	kfree(md_buf);
940 	return rc;
941 }
942 
core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp * tg_pt_gp)943 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
944 {
945 	struct se_dev_entry *se_deve;
946 	struct se_lun *lun;
947 	struct se_lun_acl *lacl;
948 
949 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
950 	list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
951 				lun_tg_pt_gp_link) {
952 		/*
953 		 * After an implicit target port asymmetric access state
954 		 * change, a device server shall establish a unit attention
955 		 * condition for the initiator port associated with every I_T
956 		 * nexus with the additional sense code set to ASYMMETRIC
957 		 * ACCESS STATE CHANGED.
958 		 *
959 		 * After an explicit target port asymmetric access state
960 		 * change, a device server shall establish a unit attention
961 		 * condition with the additional sense code set to ASYMMETRIC
962 		 * ACCESS STATE CHANGED for the initiator port associated with
963 		 * every I_T nexus other than the I_T nexus on which the SET
964 		 * TARGET PORT GROUPS command
965 		 */
966 		if (!percpu_ref_tryget_live(&lun->lun_ref))
967 			continue;
968 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
969 
970 		spin_lock(&lun->lun_deve_lock);
971 		list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
972 			lacl = rcu_dereference_check(se_deve->se_lun_acl,
973 					lockdep_is_held(&lun->lun_deve_lock));
974 
975 			/*
976 			 * spc4r37 p.242:
977 			 * After an explicit target port asymmetric access
978 			 * state change, a device server shall establish a
979 			 * unit attention condition with the additional sense
980 			 * code set to ASYMMETRIC ACCESS STATE CHANGED for
981 			 * the initiator port associated with every I_T nexus
982 			 * other than the I_T nexus on which the SET TARGET
983 			 * PORT GROUPS command was received.
984 			 */
985 			if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
986 			     ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
987 			   (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
988 			    (tg_pt_gp->tg_pt_gp_alua_lun == lun))
989 				continue;
990 
991 			/*
992 			 * se_deve->se_lun_acl pointer may be NULL for a
993 			 * entry created without explicit Node+MappedLUN ACLs
994 			 */
995 			if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
996 			    (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
997 				continue;
998 
999 			core_scsi3_ua_allocate(se_deve, 0x2A,
1000 				ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
1001 		}
1002 		spin_unlock(&lun->lun_deve_lock);
1003 
1004 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1005 		percpu_ref_put(&lun->lun_ref);
1006 	}
1007 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1008 }
1009 
core_alua_do_transition_tg_pt_work(struct work_struct * work)1010 static void core_alua_do_transition_tg_pt_work(struct work_struct *work)
1011 {
1012 	struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(work,
1013 		struct t10_alua_tg_pt_gp, tg_pt_gp_transition_work);
1014 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1015 	bool explicit = (tg_pt_gp->tg_pt_gp_alua_access_status ==
1016 			 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG);
1017 
1018 	/*
1019 	 * Update the ALUA metadata buf that has been allocated in
1020 	 * core_alua_do_port_transition(), this metadata will be written
1021 	 * to struct file.
1022 	 *
1023 	 * Note that there is the case where we do not want to update the
1024 	 * metadata when the saved metadata is being parsed in userspace
1025 	 * when setting the existing port access state and access status.
1026 	 *
1027 	 * Also note that the failure to write out the ALUA metadata to
1028 	 * struct file does NOT affect the actual ALUA transition.
1029 	 */
1030 	if (tg_pt_gp->tg_pt_gp_write_metadata) {
1031 		mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
1032 		core_alua_update_tpg_primary_metadata(tg_pt_gp);
1033 		mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
1034 	}
1035 	/*
1036 	 * Set the current primary ALUA access state to the requested new state
1037 	 */
1038 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1039 		   tg_pt_gp->tg_pt_gp_alua_pending_state);
1040 
1041 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1042 		" from primary access state %s to %s\n", (explicit) ? "explicit" :
1043 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1044 		tg_pt_gp->tg_pt_gp_id,
1045 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_previous_state),
1046 		core_alua_dump_state(tg_pt_gp->tg_pt_gp_alua_pending_state));
1047 
1048 	core_alua_queue_state_change_ua(tg_pt_gp);
1049 
1050 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1051 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1052 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1053 
1054 	if (tg_pt_gp->tg_pt_gp_transition_complete)
1055 		complete(tg_pt_gp->tg_pt_gp_transition_complete);
1056 }
1057 
core_alua_do_transition_tg_pt(struct t10_alua_tg_pt_gp * tg_pt_gp,int new_state,int explicit)1058 static int core_alua_do_transition_tg_pt(
1059 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1060 	int new_state,
1061 	int explicit)
1062 {
1063 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1064 	DECLARE_COMPLETION_ONSTACK(wait);
1065 
1066 	/* Nothing to be done here */
1067 	if (atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state) == new_state)
1068 		return 0;
1069 
1070 	if (new_state == ALUA_ACCESS_STATE_TRANSITION)
1071 		return -EAGAIN;
1072 
1073 	/*
1074 	 * Flush any pending transitions
1075 	 */
1076 	if (!explicit)
1077 		flush_work(&tg_pt_gp->tg_pt_gp_transition_work);
1078 
1079 	/*
1080 	 * Save the old primary ALUA access state, and set the current state
1081 	 * to ALUA_ACCESS_STATE_TRANSITION.
1082 	 */
1083 	tg_pt_gp->tg_pt_gp_alua_previous_state =
1084 		atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
1085 	tg_pt_gp->tg_pt_gp_alua_pending_state = new_state;
1086 
1087 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1088 			ALUA_ACCESS_STATE_TRANSITION);
1089 	tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1090 				ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1091 				ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1092 
1093 	core_alua_queue_state_change_ua(tg_pt_gp);
1094 
1095 	/*
1096 	 * Check for the optional ALUA primary state transition delay
1097 	 */
1098 	if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1099 		msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1100 
1101 	/*
1102 	 * Take a reference for workqueue item
1103 	 */
1104 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1105 	atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1106 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1107 
1108 	schedule_work(&tg_pt_gp->tg_pt_gp_transition_work);
1109 	if (explicit) {
1110 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1111 		wait_for_completion(&wait);
1112 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1113 	}
1114 
1115 	return 0;
1116 }
1117 
core_alua_do_port_transition(struct t10_alua_tg_pt_gp * l_tg_pt_gp,struct se_device * l_dev,struct se_lun * l_lun,struct se_node_acl * l_nacl,int new_state,int explicit)1118 int core_alua_do_port_transition(
1119 	struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1120 	struct se_device *l_dev,
1121 	struct se_lun *l_lun,
1122 	struct se_node_acl *l_nacl,
1123 	int new_state,
1124 	int explicit)
1125 {
1126 	struct se_device *dev;
1127 	struct t10_alua_lu_gp *lu_gp;
1128 	struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1129 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1130 	int primary, valid_states, rc = 0;
1131 
1132 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1133 	if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1134 		return -EINVAL;
1135 
1136 	local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1137 	spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1138 	lu_gp = local_lu_gp_mem->lu_gp;
1139 	atomic_inc(&lu_gp->lu_gp_ref_cnt);
1140 	spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1141 	/*
1142 	 * For storage objects that are members of the 'default_lu_gp',
1143 	 * we only do transition on the passed *l_tp_pt_gp, and not
1144 	 * on all of the matching target port groups IDs in default_lu_gp.
1145 	 */
1146 	if (!lu_gp->lu_gp_id) {
1147 		/*
1148 		 * core_alua_do_transition_tg_pt() will always return
1149 		 * success.
1150 		 */
1151 		l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1152 		l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1153 		rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1154 						   new_state, explicit);
1155 		atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1156 		return rc;
1157 	}
1158 	/*
1159 	 * For all other LU groups aside from 'default_lu_gp', walk all of
1160 	 * the associated storage objects looking for a matching target port
1161 	 * group ID from the local target port group.
1162 	 */
1163 	spin_lock(&lu_gp->lu_gp_lock);
1164 	list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1165 				lu_gp_mem_list) {
1166 
1167 		dev = lu_gp_mem->lu_gp_mem_dev;
1168 		atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1169 		spin_unlock(&lu_gp->lu_gp_lock);
1170 
1171 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1172 		list_for_each_entry(tg_pt_gp,
1173 				&dev->t10_alua.tg_pt_gps_list,
1174 				tg_pt_gp_list) {
1175 
1176 			if (!tg_pt_gp->tg_pt_gp_valid_id)
1177 				continue;
1178 			/*
1179 			 * If the target behavior port asymmetric access state
1180 			 * is changed for any target port group accessible via
1181 			 * a logical unit within a LU group, the target port
1182 			 * behavior group asymmetric access states for the same
1183 			 * target port group accessible via other logical units
1184 			 * in that LU group will also change.
1185 			 */
1186 			if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1187 				continue;
1188 
1189 			if (l_tg_pt_gp == tg_pt_gp) {
1190 				tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1191 				tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1192 			} else {
1193 				tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1194 				tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1195 			}
1196 			atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1197 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1198 			/*
1199 			 * core_alua_do_transition_tg_pt() will always return
1200 			 * success.
1201 			 */
1202 			rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1203 					new_state, explicit);
1204 
1205 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1206 			atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1207 			if (rc)
1208 				break;
1209 		}
1210 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1211 
1212 		spin_lock(&lu_gp->lu_gp_lock);
1213 		atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1214 	}
1215 	spin_unlock(&lu_gp->lu_gp_lock);
1216 
1217 	if (!rc) {
1218 		pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1219 			 " Group IDs: %hu %s transition to primary state: %s\n",
1220 			 config_item_name(&lu_gp->lu_gp_group.cg_item),
1221 			 l_tg_pt_gp->tg_pt_gp_id,
1222 			 (explicit) ? "explicit" : "implicit",
1223 			 core_alua_dump_state(new_state));
1224 	}
1225 
1226 	atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1227 	return rc;
1228 }
1229 
core_alua_update_tpg_secondary_metadata(struct se_lun * lun)1230 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1231 {
1232 	struct se_portal_group *se_tpg = lun->lun_tpg;
1233 	unsigned char *md_buf;
1234 	char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1235 	int len, rc;
1236 
1237 	mutex_lock(&lun->lun_tg_pt_md_mutex);
1238 
1239 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1240 	if (!md_buf) {
1241 		pr_err("Unable to allocate buf for ALUA metadata\n");
1242 		rc = -ENOMEM;
1243 		goto out_unlock;
1244 	}
1245 
1246 	memset(path, 0, ALUA_METADATA_PATH_LEN);
1247 	memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1248 
1249 	len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1250 			se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1251 
1252 	if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1253 		snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1254 				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1255 
1256 	len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1257 			"alua_tg_pt_status=0x%02x\n",
1258 			atomic_read(&lun->lun_tg_pt_secondary_offline),
1259 			lun->lun_tg_pt_secondary_stat);
1260 
1261 	snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%llu",
1262 			se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1263 			lun->unpacked_lun);
1264 
1265 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
1266 	kfree(md_buf);
1267 
1268 out_unlock:
1269 	mutex_unlock(&lun->lun_tg_pt_md_mutex);
1270 	return rc;
1271 }
1272 
core_alua_set_tg_pt_secondary_state(struct se_lun * lun,int explicit,int offline)1273 static int core_alua_set_tg_pt_secondary_state(
1274 	struct se_lun *lun,
1275 	int explicit,
1276 	int offline)
1277 {
1278 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1279 	int trans_delay_msecs;
1280 
1281 	spin_lock(&lun->lun_tg_pt_gp_lock);
1282 	tg_pt_gp = lun->lun_tg_pt_gp;
1283 	if (!tg_pt_gp) {
1284 		spin_unlock(&lun->lun_tg_pt_gp_lock);
1285 		pr_err("Unable to complete secondary state"
1286 				" transition\n");
1287 		return -EINVAL;
1288 	}
1289 	trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1290 	/*
1291 	 * Set the secondary ALUA target port access state to OFFLINE
1292 	 * or release the previously secondary state for struct se_lun
1293 	 */
1294 	if (offline)
1295 		atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1296 	else
1297 		atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1298 
1299 	lun->lun_tg_pt_secondary_stat = (explicit) ?
1300 			ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1301 			ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1302 
1303 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1304 		" to secondary access state: %s\n", (explicit) ? "explicit" :
1305 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1306 		tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1307 
1308 	spin_unlock(&lun->lun_tg_pt_gp_lock);
1309 	/*
1310 	 * Do the optional transition delay after we set the secondary
1311 	 * ALUA access state.
1312 	 */
1313 	if (trans_delay_msecs != 0)
1314 		msleep_interruptible(trans_delay_msecs);
1315 	/*
1316 	 * See if we need to update the ALUA fabric port metadata for
1317 	 * secondary state and status
1318 	 */
1319 	if (lun->lun_tg_pt_secondary_write_md)
1320 		core_alua_update_tpg_secondary_metadata(lun);
1321 
1322 	return 0;
1323 }
1324 
1325 struct t10_alua_lba_map *
core_alua_allocate_lba_map(struct list_head * list,u64 first_lba,u64 last_lba)1326 core_alua_allocate_lba_map(struct list_head *list,
1327 			   u64 first_lba, u64 last_lba)
1328 {
1329 	struct t10_alua_lba_map *lba_map;
1330 
1331 	lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1332 	if (!lba_map) {
1333 		pr_err("Unable to allocate struct t10_alua_lba_map\n");
1334 		return ERR_PTR(-ENOMEM);
1335 	}
1336 	INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1337 	lba_map->lba_map_first_lba = first_lba;
1338 	lba_map->lba_map_last_lba = last_lba;
1339 
1340 	list_add_tail(&lba_map->lba_map_list, list);
1341 	return lba_map;
1342 }
1343 
1344 int
core_alua_allocate_lba_map_mem(struct t10_alua_lba_map * lba_map,int pg_id,int state)1345 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1346 			       int pg_id, int state)
1347 {
1348 	struct t10_alua_lba_map_member *lba_map_mem;
1349 
1350 	list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1351 			    lba_map_mem_list) {
1352 		if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1353 			pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1354 			return -EINVAL;
1355 		}
1356 	}
1357 
1358 	lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1359 	if (!lba_map_mem) {
1360 		pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1361 		return -ENOMEM;
1362 	}
1363 	lba_map_mem->lba_map_mem_alua_state = state;
1364 	lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1365 
1366 	list_add_tail(&lba_map_mem->lba_map_mem_list,
1367 		      &lba_map->lba_map_mem_list);
1368 	return 0;
1369 }
1370 
1371 void
core_alua_free_lba_map(struct list_head * lba_list)1372 core_alua_free_lba_map(struct list_head *lba_list)
1373 {
1374 	struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1375 	struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1376 
1377 	list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1378 				 lba_map_list) {
1379 		list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1380 					 &lba_map->lba_map_mem_list,
1381 					 lba_map_mem_list) {
1382 			list_del(&lba_map_mem->lba_map_mem_list);
1383 			kmem_cache_free(t10_alua_lba_map_mem_cache,
1384 					lba_map_mem);
1385 		}
1386 		list_del(&lba_map->lba_map_list);
1387 		kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1388 	}
1389 }
1390 
1391 void
core_alua_set_lba_map(struct se_device * dev,struct list_head * lba_map_list,int segment_size,int segment_mult)1392 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1393 		      int segment_size, int segment_mult)
1394 {
1395 	struct list_head old_lba_map_list;
1396 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1397 	int activate = 0, supported;
1398 
1399 	INIT_LIST_HEAD(&old_lba_map_list);
1400 	spin_lock(&dev->t10_alua.lba_map_lock);
1401 	dev->t10_alua.lba_map_segment_size = segment_size;
1402 	dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1403 	list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1404 	if (lba_map_list) {
1405 		list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1406 		activate = 1;
1407 	}
1408 	spin_unlock(&dev->t10_alua.lba_map_lock);
1409 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1410 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1411 			    tg_pt_gp_list) {
1412 
1413 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1414 			continue;
1415 		supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1416 		if (activate)
1417 			supported |= ALUA_LBD_SUP;
1418 		else
1419 			supported &= ~ALUA_LBD_SUP;
1420 		tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1421 	}
1422 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1423 	core_alua_free_lba_map(&old_lba_map_list);
1424 }
1425 
1426 struct t10_alua_lu_gp *
core_alua_allocate_lu_gp(const char * name,int def_group)1427 core_alua_allocate_lu_gp(const char *name, int def_group)
1428 {
1429 	struct t10_alua_lu_gp *lu_gp;
1430 
1431 	lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1432 	if (!lu_gp) {
1433 		pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1434 		return ERR_PTR(-ENOMEM);
1435 	}
1436 	INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1437 	INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1438 	spin_lock_init(&lu_gp->lu_gp_lock);
1439 	atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1440 
1441 	if (def_group) {
1442 		lu_gp->lu_gp_id = alua_lu_gps_counter++;
1443 		lu_gp->lu_gp_valid_id = 1;
1444 		alua_lu_gps_count++;
1445 	}
1446 
1447 	return lu_gp;
1448 }
1449 
core_alua_set_lu_gp_id(struct t10_alua_lu_gp * lu_gp,u16 lu_gp_id)1450 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1451 {
1452 	struct t10_alua_lu_gp *lu_gp_tmp;
1453 	u16 lu_gp_id_tmp;
1454 	/*
1455 	 * The lu_gp->lu_gp_id may only be set once..
1456 	 */
1457 	if (lu_gp->lu_gp_valid_id) {
1458 		pr_warn("ALUA LU Group already has a valid ID,"
1459 			" ignoring request\n");
1460 		return -EINVAL;
1461 	}
1462 
1463 	spin_lock(&lu_gps_lock);
1464 	if (alua_lu_gps_count == 0x0000ffff) {
1465 		pr_err("Maximum ALUA alua_lu_gps_count:"
1466 				" 0x0000ffff reached\n");
1467 		spin_unlock(&lu_gps_lock);
1468 		kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1469 		return -ENOSPC;
1470 	}
1471 again:
1472 	lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1473 				alua_lu_gps_counter++;
1474 
1475 	list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1476 		if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1477 			if (!lu_gp_id)
1478 				goto again;
1479 
1480 			pr_warn("ALUA Logical Unit Group ID: %hu"
1481 				" already exists, ignoring request\n",
1482 				lu_gp_id);
1483 			spin_unlock(&lu_gps_lock);
1484 			return -EINVAL;
1485 		}
1486 	}
1487 
1488 	lu_gp->lu_gp_id = lu_gp_id_tmp;
1489 	lu_gp->lu_gp_valid_id = 1;
1490 	list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1491 	alua_lu_gps_count++;
1492 	spin_unlock(&lu_gps_lock);
1493 
1494 	return 0;
1495 }
1496 
1497 static struct t10_alua_lu_gp_member *
core_alua_allocate_lu_gp_mem(struct se_device * dev)1498 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1499 {
1500 	struct t10_alua_lu_gp_member *lu_gp_mem;
1501 
1502 	lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1503 	if (!lu_gp_mem) {
1504 		pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1505 		return ERR_PTR(-ENOMEM);
1506 	}
1507 	INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1508 	spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1509 	atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1510 
1511 	lu_gp_mem->lu_gp_mem_dev = dev;
1512 	dev->dev_alua_lu_gp_mem = lu_gp_mem;
1513 
1514 	return lu_gp_mem;
1515 }
1516 
core_alua_free_lu_gp(struct t10_alua_lu_gp * lu_gp)1517 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1518 {
1519 	struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1520 	/*
1521 	 * Once we have reached this point, config_item_put() has
1522 	 * already been called from target_core_alua_drop_lu_gp().
1523 	 *
1524 	 * Here, we remove the *lu_gp from the global list so that
1525 	 * no associations can be made while we are releasing
1526 	 * struct t10_alua_lu_gp.
1527 	 */
1528 	spin_lock(&lu_gps_lock);
1529 	list_del(&lu_gp->lu_gp_node);
1530 	alua_lu_gps_count--;
1531 	spin_unlock(&lu_gps_lock);
1532 	/*
1533 	 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1534 	 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1535 	 * released with core_alua_put_lu_gp_from_name()
1536 	 */
1537 	while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1538 		cpu_relax();
1539 	/*
1540 	 * Release reference to struct t10_alua_lu_gp * from all associated
1541 	 * struct se_device.
1542 	 */
1543 	spin_lock(&lu_gp->lu_gp_lock);
1544 	list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1545 				&lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1546 		if (lu_gp_mem->lu_gp_assoc) {
1547 			list_del(&lu_gp_mem->lu_gp_mem_list);
1548 			lu_gp->lu_gp_members--;
1549 			lu_gp_mem->lu_gp_assoc = 0;
1550 		}
1551 		spin_unlock(&lu_gp->lu_gp_lock);
1552 		/*
1553 		 *
1554 		 * lu_gp_mem is associated with a single
1555 		 * struct se_device->dev_alua_lu_gp_mem, and is released when
1556 		 * struct se_device is released via core_alua_free_lu_gp_mem().
1557 		 *
1558 		 * If the passed lu_gp does NOT match the default_lu_gp, assume
1559 		 * we want to re-associate a given lu_gp_mem with default_lu_gp.
1560 		 */
1561 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1562 		if (lu_gp != default_lu_gp)
1563 			__core_alua_attach_lu_gp_mem(lu_gp_mem,
1564 					default_lu_gp);
1565 		else
1566 			lu_gp_mem->lu_gp = NULL;
1567 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1568 
1569 		spin_lock(&lu_gp->lu_gp_lock);
1570 	}
1571 	spin_unlock(&lu_gp->lu_gp_lock);
1572 
1573 	kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1574 }
1575 
core_alua_free_lu_gp_mem(struct se_device * dev)1576 void core_alua_free_lu_gp_mem(struct se_device *dev)
1577 {
1578 	struct t10_alua_lu_gp *lu_gp;
1579 	struct t10_alua_lu_gp_member *lu_gp_mem;
1580 
1581 	lu_gp_mem = dev->dev_alua_lu_gp_mem;
1582 	if (!lu_gp_mem)
1583 		return;
1584 
1585 	while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1586 		cpu_relax();
1587 
1588 	spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1589 	lu_gp = lu_gp_mem->lu_gp;
1590 	if (lu_gp) {
1591 		spin_lock(&lu_gp->lu_gp_lock);
1592 		if (lu_gp_mem->lu_gp_assoc) {
1593 			list_del(&lu_gp_mem->lu_gp_mem_list);
1594 			lu_gp->lu_gp_members--;
1595 			lu_gp_mem->lu_gp_assoc = 0;
1596 		}
1597 		spin_unlock(&lu_gp->lu_gp_lock);
1598 		lu_gp_mem->lu_gp = NULL;
1599 	}
1600 	spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1601 
1602 	kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1603 }
1604 
core_alua_get_lu_gp_by_name(const char * name)1605 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1606 {
1607 	struct t10_alua_lu_gp *lu_gp;
1608 	struct config_item *ci;
1609 
1610 	spin_lock(&lu_gps_lock);
1611 	list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1612 		if (!lu_gp->lu_gp_valid_id)
1613 			continue;
1614 		ci = &lu_gp->lu_gp_group.cg_item;
1615 		if (!strcmp(config_item_name(ci), name)) {
1616 			atomic_inc(&lu_gp->lu_gp_ref_cnt);
1617 			spin_unlock(&lu_gps_lock);
1618 			return lu_gp;
1619 		}
1620 	}
1621 	spin_unlock(&lu_gps_lock);
1622 
1623 	return NULL;
1624 }
1625 
core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp * lu_gp)1626 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1627 {
1628 	spin_lock(&lu_gps_lock);
1629 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1630 	spin_unlock(&lu_gps_lock);
1631 }
1632 
1633 /*
1634  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1635  */
__core_alua_attach_lu_gp_mem(struct t10_alua_lu_gp_member * lu_gp_mem,struct t10_alua_lu_gp * lu_gp)1636 void __core_alua_attach_lu_gp_mem(
1637 	struct t10_alua_lu_gp_member *lu_gp_mem,
1638 	struct t10_alua_lu_gp *lu_gp)
1639 {
1640 	spin_lock(&lu_gp->lu_gp_lock);
1641 	lu_gp_mem->lu_gp = lu_gp;
1642 	lu_gp_mem->lu_gp_assoc = 1;
1643 	list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1644 	lu_gp->lu_gp_members++;
1645 	spin_unlock(&lu_gp->lu_gp_lock);
1646 }
1647 
1648 /*
1649  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1650  */
__core_alua_drop_lu_gp_mem(struct t10_alua_lu_gp_member * lu_gp_mem,struct t10_alua_lu_gp * lu_gp)1651 void __core_alua_drop_lu_gp_mem(
1652 	struct t10_alua_lu_gp_member *lu_gp_mem,
1653 	struct t10_alua_lu_gp *lu_gp)
1654 {
1655 	spin_lock(&lu_gp->lu_gp_lock);
1656 	list_del(&lu_gp_mem->lu_gp_mem_list);
1657 	lu_gp_mem->lu_gp = NULL;
1658 	lu_gp_mem->lu_gp_assoc = 0;
1659 	lu_gp->lu_gp_members--;
1660 	spin_unlock(&lu_gp->lu_gp_lock);
1661 }
1662 
core_alua_allocate_tg_pt_gp(struct se_device * dev,const char * name,int def_group)1663 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1664 		const char *name, int def_group)
1665 {
1666 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1667 
1668 	tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1669 	if (!tg_pt_gp) {
1670 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1671 		return NULL;
1672 	}
1673 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1674 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1675 	mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1676 	spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1677 	atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1678 	INIT_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1679 		  core_alua_do_transition_tg_pt_work);
1680 	tg_pt_gp->tg_pt_gp_dev = dev;
1681 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1682 		ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1683 	/*
1684 	 * Enable both explicit and implicit ALUA support by default
1685 	 */
1686 	tg_pt_gp->tg_pt_gp_alua_access_type =
1687 			TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1688 	/*
1689 	 * Set the default Active/NonOptimized Delay in milliseconds
1690 	 */
1691 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1692 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1693 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1694 
1695 	/*
1696 	 * Enable all supported states
1697 	 */
1698 	tg_pt_gp->tg_pt_gp_alua_supported_states =
1699 	    ALUA_T_SUP | ALUA_O_SUP |
1700 	    ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1701 
1702 	if (def_group) {
1703 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1704 		tg_pt_gp->tg_pt_gp_id =
1705 				dev->t10_alua.alua_tg_pt_gps_counter++;
1706 		tg_pt_gp->tg_pt_gp_valid_id = 1;
1707 		dev->t10_alua.alua_tg_pt_gps_count++;
1708 		list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1709 			      &dev->t10_alua.tg_pt_gps_list);
1710 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1711 	}
1712 
1713 	return tg_pt_gp;
1714 }
1715 
core_alua_set_tg_pt_gp_id(struct t10_alua_tg_pt_gp * tg_pt_gp,u16 tg_pt_gp_id)1716 int core_alua_set_tg_pt_gp_id(
1717 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1718 	u16 tg_pt_gp_id)
1719 {
1720 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1721 	struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1722 	u16 tg_pt_gp_id_tmp;
1723 
1724 	/*
1725 	 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1726 	 */
1727 	if (tg_pt_gp->tg_pt_gp_valid_id) {
1728 		pr_warn("ALUA TG PT Group already has a valid ID,"
1729 			" ignoring request\n");
1730 		return -EINVAL;
1731 	}
1732 
1733 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1734 	if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1735 		pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1736 			" 0x0000ffff reached\n");
1737 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1738 		return -ENOSPC;
1739 	}
1740 again:
1741 	tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1742 			dev->t10_alua.alua_tg_pt_gps_counter++;
1743 
1744 	list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1745 			tg_pt_gp_list) {
1746 		if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1747 			if (!tg_pt_gp_id)
1748 				goto again;
1749 
1750 			pr_err("ALUA Target Port Group ID: %hu already"
1751 				" exists, ignoring request\n", tg_pt_gp_id);
1752 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1753 			return -EINVAL;
1754 		}
1755 	}
1756 
1757 	tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1758 	tg_pt_gp->tg_pt_gp_valid_id = 1;
1759 	list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1760 			&dev->t10_alua.tg_pt_gps_list);
1761 	dev->t10_alua.alua_tg_pt_gps_count++;
1762 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1763 
1764 	return 0;
1765 }
1766 
core_alua_free_tg_pt_gp(struct t10_alua_tg_pt_gp * tg_pt_gp)1767 void core_alua_free_tg_pt_gp(
1768 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1769 {
1770 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1771 	struct se_lun *lun, *next;
1772 
1773 	/*
1774 	 * Once we have reached this point, config_item_put() has already
1775 	 * been called from target_core_alua_drop_tg_pt_gp().
1776 	 *
1777 	 * Here we remove *tg_pt_gp from the global list so that
1778 	 * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1779 	 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1780 	 */
1781 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1782 	list_del(&tg_pt_gp->tg_pt_gp_list);
1783 	dev->t10_alua.alua_tg_pt_gps_counter--;
1784 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1785 
1786 	flush_work(&tg_pt_gp->tg_pt_gp_transition_work);
1787 
1788 	/*
1789 	 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1790 	 * core_alua_get_tg_pt_gp_by_name() in
1791 	 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1792 	 * to be released with core_alua_put_tg_pt_gp_from_name().
1793 	 */
1794 	while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1795 		cpu_relax();
1796 
1797 	/*
1798 	 * Release reference to struct t10_alua_tg_pt_gp from all associated
1799 	 * struct se_port.
1800 	 */
1801 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1802 	list_for_each_entry_safe(lun, next,
1803 			&tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1804 		list_del_init(&lun->lun_tg_pt_gp_link);
1805 		tg_pt_gp->tg_pt_gp_members--;
1806 
1807 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1808 		/*
1809 		 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1810 		 * assume we want to re-associate a given tg_pt_gp_mem with
1811 		 * default_tg_pt_gp.
1812 		 */
1813 		spin_lock(&lun->lun_tg_pt_gp_lock);
1814 		if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1815 			__target_attach_tg_pt_gp(lun,
1816 					dev->t10_alua.default_tg_pt_gp);
1817 		} else
1818 			lun->lun_tg_pt_gp = NULL;
1819 		spin_unlock(&lun->lun_tg_pt_gp_lock);
1820 
1821 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1822 	}
1823 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1824 
1825 	kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1826 }
1827 
core_alua_get_tg_pt_gp_by_name(struct se_device * dev,const char * name)1828 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1829 		struct se_device *dev, const char *name)
1830 {
1831 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1832 	struct config_item *ci;
1833 
1834 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1835 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1836 			tg_pt_gp_list) {
1837 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1838 			continue;
1839 		ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1840 		if (!strcmp(config_item_name(ci), name)) {
1841 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1842 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1843 			return tg_pt_gp;
1844 		}
1845 	}
1846 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1847 
1848 	return NULL;
1849 }
1850 
core_alua_put_tg_pt_gp_from_name(struct t10_alua_tg_pt_gp * tg_pt_gp)1851 static void core_alua_put_tg_pt_gp_from_name(
1852 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1853 {
1854 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1855 
1856 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1857 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1858 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1859 }
1860 
__target_attach_tg_pt_gp(struct se_lun * lun,struct t10_alua_tg_pt_gp * tg_pt_gp)1861 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1862 		struct t10_alua_tg_pt_gp *tg_pt_gp)
1863 {
1864 	struct se_dev_entry *se_deve;
1865 
1866 	assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1867 
1868 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1869 	lun->lun_tg_pt_gp = tg_pt_gp;
1870 	list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1871 	tg_pt_gp->tg_pt_gp_members++;
1872 	spin_lock(&lun->lun_deve_lock);
1873 	list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1874 		core_scsi3_ua_allocate(se_deve, 0x3f,
1875 				       ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1876 	spin_unlock(&lun->lun_deve_lock);
1877 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1878 }
1879 
target_attach_tg_pt_gp(struct se_lun * lun,struct t10_alua_tg_pt_gp * tg_pt_gp)1880 void target_attach_tg_pt_gp(struct se_lun *lun,
1881 		struct t10_alua_tg_pt_gp *tg_pt_gp)
1882 {
1883 	spin_lock(&lun->lun_tg_pt_gp_lock);
1884 	__target_attach_tg_pt_gp(lun, tg_pt_gp);
1885 	spin_unlock(&lun->lun_tg_pt_gp_lock);
1886 }
1887 
__target_detach_tg_pt_gp(struct se_lun * lun,struct t10_alua_tg_pt_gp * tg_pt_gp)1888 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1889 		struct t10_alua_tg_pt_gp *tg_pt_gp)
1890 {
1891 	assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1892 
1893 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1894 	list_del_init(&lun->lun_tg_pt_gp_link);
1895 	tg_pt_gp->tg_pt_gp_members--;
1896 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1897 
1898 	lun->lun_tg_pt_gp = NULL;
1899 }
1900 
target_detach_tg_pt_gp(struct se_lun * lun)1901 void target_detach_tg_pt_gp(struct se_lun *lun)
1902 {
1903 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1904 
1905 	spin_lock(&lun->lun_tg_pt_gp_lock);
1906 	tg_pt_gp = lun->lun_tg_pt_gp;
1907 	if (tg_pt_gp)
1908 		__target_detach_tg_pt_gp(lun, tg_pt_gp);
1909 	spin_unlock(&lun->lun_tg_pt_gp_lock);
1910 }
1911 
core_alua_show_tg_pt_gp_info(struct se_lun * lun,char * page)1912 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1913 {
1914 	struct config_item *tg_pt_ci;
1915 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1916 	ssize_t len = 0;
1917 
1918 	spin_lock(&lun->lun_tg_pt_gp_lock);
1919 	tg_pt_gp = lun->lun_tg_pt_gp;
1920 	if (tg_pt_gp) {
1921 		tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1922 		len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1923 			" %hu\nTG Port Primary Access State: %s\nTG Port "
1924 			"Primary Access Status: %s\nTG Port Secondary Access"
1925 			" State: %s\nTG Port Secondary Access Status: %s\n",
1926 			config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1927 			core_alua_dump_state(atomic_read(
1928 					&tg_pt_gp->tg_pt_gp_alua_access_state)),
1929 			core_alua_dump_status(
1930 				tg_pt_gp->tg_pt_gp_alua_access_status),
1931 			atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1932 			"Offline" : "None",
1933 			core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1934 	}
1935 	spin_unlock(&lun->lun_tg_pt_gp_lock);
1936 
1937 	return len;
1938 }
1939 
core_alua_store_tg_pt_gp_info(struct se_lun * lun,const char * page,size_t count)1940 ssize_t core_alua_store_tg_pt_gp_info(
1941 	struct se_lun *lun,
1942 	const char *page,
1943 	size_t count)
1944 {
1945 	struct se_portal_group *tpg = lun->lun_tpg;
1946 	/*
1947 	 * rcu_dereference_raw protected by se_lun->lun_group symlink
1948 	 * reference to se_device->dev_group.
1949 	 */
1950 	struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1951 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1952 	unsigned char buf[TG_PT_GROUP_NAME_BUF];
1953 	int move = 0;
1954 
1955 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH ||
1956 	    (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1957 		return -ENODEV;
1958 
1959 	if (count > TG_PT_GROUP_NAME_BUF) {
1960 		pr_err("ALUA Target Port Group alias too large!\n");
1961 		return -EINVAL;
1962 	}
1963 	memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1964 	memcpy(buf, page, count);
1965 	/*
1966 	 * Any ALUA target port group alias besides "NULL" means we will be
1967 	 * making a new group association.
1968 	 */
1969 	if (strcmp(strstrip(buf), "NULL")) {
1970 		/*
1971 		 * core_alua_get_tg_pt_gp_by_name() will increment reference to
1972 		 * struct t10_alua_tg_pt_gp.  This reference is released with
1973 		 * core_alua_put_tg_pt_gp_from_name() below.
1974 		 */
1975 		tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1976 					strstrip(buf));
1977 		if (!tg_pt_gp_new)
1978 			return -ENODEV;
1979 	}
1980 
1981 	spin_lock(&lun->lun_tg_pt_gp_lock);
1982 	tg_pt_gp = lun->lun_tg_pt_gp;
1983 	if (tg_pt_gp) {
1984 		/*
1985 		 * Clearing an existing tg_pt_gp association, and replacing
1986 		 * with the default_tg_pt_gp.
1987 		 */
1988 		if (!tg_pt_gp_new) {
1989 			pr_debug("Target_Core_ConfigFS: Moving"
1990 				" %s/tpgt_%hu/%s from ALUA Target Port Group:"
1991 				" alua/%s, ID: %hu back to"
1992 				" default_tg_pt_gp\n",
1993 				tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1994 				tpg->se_tpg_tfo->tpg_get_tag(tpg),
1995 				config_item_name(&lun->lun_group.cg_item),
1996 				config_item_name(
1997 					&tg_pt_gp->tg_pt_gp_group.cg_item),
1998 				tg_pt_gp->tg_pt_gp_id);
1999 
2000 			__target_detach_tg_pt_gp(lun, tg_pt_gp);
2001 			__target_attach_tg_pt_gp(lun,
2002 					dev->t10_alua.default_tg_pt_gp);
2003 			spin_unlock(&lun->lun_tg_pt_gp_lock);
2004 
2005 			return count;
2006 		}
2007 		__target_detach_tg_pt_gp(lun, tg_pt_gp);
2008 		move = 1;
2009 	}
2010 
2011 	__target_attach_tg_pt_gp(lun, tg_pt_gp_new);
2012 	spin_unlock(&lun->lun_tg_pt_gp_lock);
2013 	pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2014 		" Target Port Group: alua/%s, ID: %hu\n", (move) ?
2015 		"Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2016 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
2017 		config_item_name(&lun->lun_group.cg_item),
2018 		config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2019 		tg_pt_gp_new->tg_pt_gp_id);
2020 
2021 	core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2022 	return count;
2023 }
2024 
core_alua_show_access_type(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2025 ssize_t core_alua_show_access_type(
2026 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2027 	char *page)
2028 {
2029 	if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2030 	    (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2031 		return sprintf(page, "Implicit and Explicit\n");
2032 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2033 		return sprintf(page, "Implicit\n");
2034 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2035 		return sprintf(page, "Explicit\n");
2036 	else
2037 		return sprintf(page, "None\n");
2038 }
2039 
core_alua_store_access_type(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2040 ssize_t core_alua_store_access_type(
2041 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2042 	const char *page,
2043 	size_t count)
2044 {
2045 	unsigned long tmp;
2046 	int ret;
2047 
2048 	ret = kstrtoul(page, 0, &tmp);
2049 	if (ret < 0) {
2050 		pr_err("Unable to extract alua_access_type\n");
2051 		return ret;
2052 	}
2053 	if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2054 		pr_err("Illegal value for alua_access_type:"
2055 				" %lu\n", tmp);
2056 		return -EINVAL;
2057 	}
2058 	if (tmp == 3)
2059 		tg_pt_gp->tg_pt_gp_alua_access_type =
2060 			TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2061 	else if (tmp == 2)
2062 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2063 	else if (tmp == 1)
2064 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2065 	else
2066 		tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2067 
2068 	return count;
2069 }
2070 
core_alua_show_nonop_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2071 ssize_t core_alua_show_nonop_delay_msecs(
2072 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2073 	char *page)
2074 {
2075 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2076 }
2077 
core_alua_store_nonop_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2078 ssize_t core_alua_store_nonop_delay_msecs(
2079 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2080 	const char *page,
2081 	size_t count)
2082 {
2083 	unsigned long tmp;
2084 	int ret;
2085 
2086 	ret = kstrtoul(page, 0, &tmp);
2087 	if (ret < 0) {
2088 		pr_err("Unable to extract nonop_delay_msecs\n");
2089 		return ret;
2090 	}
2091 	if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2092 		pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2093 			" ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2094 			ALUA_MAX_NONOP_DELAY_MSECS);
2095 		return -EINVAL;
2096 	}
2097 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2098 
2099 	return count;
2100 }
2101 
core_alua_show_trans_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2102 ssize_t core_alua_show_trans_delay_msecs(
2103 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2104 	char *page)
2105 {
2106 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2107 }
2108 
core_alua_store_trans_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2109 ssize_t core_alua_store_trans_delay_msecs(
2110 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2111 	const char *page,
2112 	size_t count)
2113 {
2114 	unsigned long tmp;
2115 	int ret;
2116 
2117 	ret = kstrtoul(page, 0, &tmp);
2118 	if (ret < 0) {
2119 		pr_err("Unable to extract trans_delay_msecs\n");
2120 		return ret;
2121 	}
2122 	if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2123 		pr_err("Passed trans_delay_msecs: %lu, exceeds"
2124 			" ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2125 			ALUA_MAX_TRANS_DELAY_MSECS);
2126 		return -EINVAL;
2127 	}
2128 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2129 
2130 	return count;
2131 }
2132 
core_alua_show_implicit_trans_secs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2133 ssize_t core_alua_show_implicit_trans_secs(
2134 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2135 	char *page)
2136 {
2137 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2138 }
2139 
core_alua_store_implicit_trans_secs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2140 ssize_t core_alua_store_implicit_trans_secs(
2141 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2142 	const char *page,
2143 	size_t count)
2144 {
2145 	unsigned long tmp;
2146 	int ret;
2147 
2148 	ret = kstrtoul(page, 0, &tmp);
2149 	if (ret < 0) {
2150 		pr_err("Unable to extract implicit_trans_secs\n");
2151 		return ret;
2152 	}
2153 	if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2154 		pr_err("Passed implicit_trans_secs: %lu, exceeds"
2155 			" ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2156 			ALUA_MAX_IMPLICIT_TRANS_SECS);
2157 		return  -EINVAL;
2158 	}
2159 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2160 
2161 	return count;
2162 }
2163 
core_alua_show_preferred_bit(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2164 ssize_t core_alua_show_preferred_bit(
2165 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2166 	char *page)
2167 {
2168 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2169 }
2170 
core_alua_store_preferred_bit(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2171 ssize_t core_alua_store_preferred_bit(
2172 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2173 	const char *page,
2174 	size_t count)
2175 {
2176 	unsigned long tmp;
2177 	int ret;
2178 
2179 	ret = kstrtoul(page, 0, &tmp);
2180 	if (ret < 0) {
2181 		pr_err("Unable to extract preferred ALUA value\n");
2182 		return ret;
2183 	}
2184 	if ((tmp != 0) && (tmp != 1)) {
2185 		pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2186 		return -EINVAL;
2187 	}
2188 	tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2189 
2190 	return count;
2191 }
2192 
core_alua_show_offline_bit(struct se_lun * lun,char * page)2193 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2194 {
2195 	return sprintf(page, "%d\n",
2196 		atomic_read(&lun->lun_tg_pt_secondary_offline));
2197 }
2198 
core_alua_store_offline_bit(struct se_lun * lun,const char * page,size_t count)2199 ssize_t core_alua_store_offline_bit(
2200 	struct se_lun *lun,
2201 	const char *page,
2202 	size_t count)
2203 {
2204 	/*
2205 	 * rcu_dereference_raw protected by se_lun->lun_group symlink
2206 	 * reference to se_device->dev_group.
2207 	 */
2208 	struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2209 	unsigned long tmp;
2210 	int ret;
2211 
2212 	if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH ||
2213 	    (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2214 		return -ENODEV;
2215 
2216 	ret = kstrtoul(page, 0, &tmp);
2217 	if (ret < 0) {
2218 		pr_err("Unable to extract alua_tg_pt_offline value\n");
2219 		return ret;
2220 	}
2221 	if ((tmp != 0) && (tmp != 1)) {
2222 		pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2223 				tmp);
2224 		return -EINVAL;
2225 	}
2226 
2227 	ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2228 	if (ret < 0)
2229 		return -EINVAL;
2230 
2231 	return count;
2232 }
2233 
core_alua_show_secondary_status(struct se_lun * lun,char * page)2234 ssize_t core_alua_show_secondary_status(
2235 	struct se_lun *lun,
2236 	char *page)
2237 {
2238 	return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2239 }
2240 
core_alua_store_secondary_status(struct se_lun * lun,const char * page,size_t count)2241 ssize_t core_alua_store_secondary_status(
2242 	struct se_lun *lun,
2243 	const char *page,
2244 	size_t count)
2245 {
2246 	unsigned long tmp;
2247 	int ret;
2248 
2249 	ret = kstrtoul(page, 0, &tmp);
2250 	if (ret < 0) {
2251 		pr_err("Unable to extract alua_tg_pt_status\n");
2252 		return ret;
2253 	}
2254 	if ((tmp != ALUA_STATUS_NONE) &&
2255 	    (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2256 	    (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2257 		pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2258 				tmp);
2259 		return -EINVAL;
2260 	}
2261 	lun->lun_tg_pt_secondary_stat = (int)tmp;
2262 
2263 	return count;
2264 }
2265 
core_alua_show_secondary_write_metadata(struct se_lun * lun,char * page)2266 ssize_t core_alua_show_secondary_write_metadata(
2267 	struct se_lun *lun,
2268 	char *page)
2269 {
2270 	return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2271 }
2272 
core_alua_store_secondary_write_metadata(struct se_lun * lun,const char * page,size_t count)2273 ssize_t core_alua_store_secondary_write_metadata(
2274 	struct se_lun *lun,
2275 	const char *page,
2276 	size_t count)
2277 {
2278 	unsigned long tmp;
2279 	int ret;
2280 
2281 	ret = kstrtoul(page, 0, &tmp);
2282 	if (ret < 0) {
2283 		pr_err("Unable to extract alua_tg_pt_write_md\n");
2284 		return ret;
2285 	}
2286 	if ((tmp != 0) && (tmp != 1)) {
2287 		pr_err("Illegal value for alua_tg_pt_write_md:"
2288 				" %lu\n", tmp);
2289 		return -EINVAL;
2290 	}
2291 	lun->lun_tg_pt_secondary_write_md = (int)tmp;
2292 
2293 	return count;
2294 }
2295 
core_setup_alua(struct se_device * dev)2296 int core_setup_alua(struct se_device *dev)
2297 {
2298 	if (!(dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) &&
2299 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2300 		struct t10_alua_lu_gp_member *lu_gp_mem;
2301 
2302 		/*
2303 		 * Associate this struct se_device with the default ALUA
2304 		 * LUN Group.
2305 		 */
2306 		lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2307 		if (IS_ERR(lu_gp_mem))
2308 			return PTR_ERR(lu_gp_mem);
2309 
2310 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2311 		__core_alua_attach_lu_gp_mem(lu_gp_mem,
2312 				default_lu_gp);
2313 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2314 
2315 		pr_debug("%s: Adding to default ALUA LU Group:"
2316 			" core/alua/lu_gps/default_lu_gp\n",
2317 			dev->transport->name);
2318 	}
2319 
2320 	return 0;
2321 }
2322