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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.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
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 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
target_emulate_set_target_port_groups(struct se_cmd * cmd)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 
set_ascq(struct se_cmd * cmd,u8 alua_ascq)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 
core_alua_state_nonoptimized(struct se_cmd * cmd,unsigned char * cdb,int nonop_delay_msecs)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 
core_alua_state_lba_dependent(struct se_cmd * cmd,struct t10_alua_tg_pt_gp * tg_pt_gp)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 
core_alua_state_standby(struct se_cmd * cmd,unsigned char * cdb)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:
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 
core_alua_state_unavailable(struct se_cmd * cmd,unsigned char * cdb)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 
core_alua_state_transition(struct se_cmd * cmd,unsigned char * cdb)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
target_alua_state_check(struct se_cmd * cmd)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
core_alua_check_transition(int state,int valid,int * primary)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 
core_alua_dump_state(int state)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 
core_alua_dump_status(int status)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  */
core_alua_check_nonop_delay(struct se_cmd * cmd)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  */
core_alua_write_tpg_metadata(const char * path,unsigned char * md_buf,u32 md_buf_len)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  */
core_alua_update_tpg_primary_metadata(struct t10_alua_tg_pt_gp * tg_pt_gp)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 
core_alua_do_transition_tg_pt_work(struct work_struct * work)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 
core_alua_do_transition_tg_pt(struct t10_alua_tg_pt_gp * tg_pt_gp,int new_state,int explicit)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 		schedule_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work,
1130 				      transition_tmo);
1131 	} else {
1132 		tg_pt_gp->tg_pt_gp_transition_complete = &wait;
1133 		schedule_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work, 0);
1134 		wait_for_completion(&wait);
1135 		tg_pt_gp->tg_pt_gp_transition_complete = NULL;
1136 	}
1137 
1138 	return 0;
1139 }
1140 
core_alua_do_port_transition(struct t10_alua_tg_pt_gp * l_tg_pt_gp,struct se_device * l_dev,struct se_port * l_port,struct se_node_acl * l_nacl,int new_state,int explicit)1141 int core_alua_do_port_transition(
1142 	struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1143 	struct se_device *l_dev,
1144 	struct se_port *l_port,
1145 	struct se_node_acl *l_nacl,
1146 	int new_state,
1147 	int explicit)
1148 {
1149 	struct se_device *dev;
1150 	struct t10_alua_lu_gp *lu_gp;
1151 	struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1152 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1153 	int primary, valid_states, rc = 0;
1154 
1155 	valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1156 	if (core_alua_check_transition(new_state, valid_states, &primary) != 0)
1157 		return -EINVAL;
1158 
1159 	local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1160 	spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1161 	lu_gp = local_lu_gp_mem->lu_gp;
1162 	atomic_inc(&lu_gp->lu_gp_ref_cnt);
1163 	spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1164 	/*
1165 	 * For storage objects that are members of the 'default_lu_gp',
1166 	 * we only do transition on the passed *l_tp_pt_gp, and not
1167 	 * on all of the matching target port groups IDs in default_lu_gp.
1168 	 */
1169 	if (!lu_gp->lu_gp_id) {
1170 		/*
1171 		 * core_alua_do_transition_tg_pt() will always return
1172 		 * success.
1173 		 */
1174 		l_tg_pt_gp->tg_pt_gp_alua_port = l_port;
1175 		l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1176 		rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1177 						   new_state, explicit);
1178 		atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1179 		return rc;
1180 	}
1181 	/*
1182 	 * For all other LU groups aside from 'default_lu_gp', walk all of
1183 	 * the associated storage objects looking for a matching target port
1184 	 * group ID from the local target port group.
1185 	 */
1186 	spin_lock(&lu_gp->lu_gp_lock);
1187 	list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1188 				lu_gp_mem_list) {
1189 
1190 		dev = lu_gp_mem->lu_gp_mem_dev;
1191 		atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1192 		spin_unlock(&lu_gp->lu_gp_lock);
1193 
1194 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1195 		list_for_each_entry(tg_pt_gp,
1196 				&dev->t10_alua.tg_pt_gps_list,
1197 				tg_pt_gp_list) {
1198 
1199 			if (!tg_pt_gp->tg_pt_gp_valid_id)
1200 				continue;
1201 			/*
1202 			 * If the target behavior port asymmetric access state
1203 			 * is changed for any target port group accessible via
1204 			 * a logical unit within a LU group, the target port
1205 			 * behavior group asymmetric access states for the same
1206 			 * target port group accessible via other logical units
1207 			 * in that LU group will also change.
1208 			 */
1209 			if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1210 				continue;
1211 
1212 			if (l_tg_pt_gp == tg_pt_gp) {
1213 				tg_pt_gp->tg_pt_gp_alua_port = l_port;
1214 				tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1215 			} else {
1216 				tg_pt_gp->tg_pt_gp_alua_port = NULL;
1217 				tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1218 			}
1219 			atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1220 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1221 			/*
1222 			 * core_alua_do_transition_tg_pt() will always return
1223 			 * success.
1224 			 */
1225 			rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1226 					new_state, explicit);
1227 
1228 			spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1229 			atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1230 			if (rc)
1231 				break;
1232 		}
1233 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1234 
1235 		spin_lock(&lu_gp->lu_gp_lock);
1236 		atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1237 	}
1238 	spin_unlock(&lu_gp->lu_gp_lock);
1239 
1240 	if (!rc) {
1241 		pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1242 			 " Group IDs: %hu %s transition to primary state: %s\n",
1243 			 config_item_name(&lu_gp->lu_gp_group.cg_item),
1244 			 l_tg_pt_gp->tg_pt_gp_id,
1245 			 (explicit) ? "explicit" : "implicit",
1246 			 core_alua_dump_state(new_state));
1247 	}
1248 
1249 	atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1250 	return rc;
1251 }
1252 
1253 /*
1254  * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
1255  */
core_alua_update_tpg_secondary_metadata(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct se_port * port)1256 static int core_alua_update_tpg_secondary_metadata(
1257 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1258 	struct se_port *port)
1259 {
1260 	unsigned char *md_buf;
1261 	struct se_portal_group *se_tpg = port->sep_tpg;
1262 	char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
1263 	int len, rc;
1264 
1265 	md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1266 	if (!md_buf) {
1267 		pr_err("Unable to allocate buf for ALUA metadata\n");
1268 		return -ENOMEM;
1269 	}
1270 
1271 	memset(path, 0, ALUA_METADATA_PATH_LEN);
1272 	memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
1273 
1274 	len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
1275 			se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
1276 
1277 	if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
1278 		snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
1279 				se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
1280 
1281 	len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1282 			"alua_tg_pt_status=0x%02x\n",
1283 			atomic_read(&port->sep_tg_pt_secondary_offline),
1284 			port->sep_tg_pt_secondary_stat);
1285 
1286 	snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
1287 			se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
1288 			port->sep_lun->unpacked_lun);
1289 
1290 	rc = core_alua_write_tpg_metadata(path, md_buf, len);
1291 	kfree(md_buf);
1292 
1293 	return rc;
1294 }
1295 
core_alua_set_tg_pt_secondary_state(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct se_port * port,int explicit,int offline)1296 static int core_alua_set_tg_pt_secondary_state(
1297 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1298 	struct se_port *port,
1299 	int explicit,
1300 	int offline)
1301 {
1302 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1303 	int trans_delay_msecs;
1304 
1305 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1306 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1307 	if (!tg_pt_gp) {
1308 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1309 		pr_err("Unable to complete secondary state"
1310 				" transition\n");
1311 		return -EINVAL;
1312 	}
1313 	trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1314 	/*
1315 	 * Set the secondary ALUA target port access state to OFFLINE
1316 	 * or release the previously secondary state for struct se_port
1317 	 */
1318 	if (offline)
1319 		atomic_set(&port->sep_tg_pt_secondary_offline, 1);
1320 	else
1321 		atomic_set(&port->sep_tg_pt_secondary_offline, 0);
1322 
1323 	port->sep_tg_pt_secondary_stat = (explicit) ?
1324 			ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1325 			ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1326 
1327 	pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1328 		" to secondary access state: %s\n", (explicit) ? "explicit" :
1329 		"implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1330 		tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1331 
1332 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1333 	/*
1334 	 * Do the optional transition delay after we set the secondary
1335 	 * ALUA access state.
1336 	 */
1337 	if (trans_delay_msecs != 0)
1338 		msleep_interruptible(trans_delay_msecs);
1339 	/*
1340 	 * See if we need to update the ALUA fabric port metadata for
1341 	 * secondary state and status
1342 	 */
1343 	if (port->sep_tg_pt_secondary_write_md) {
1344 		mutex_lock(&port->sep_tg_pt_md_mutex);
1345 		core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port);
1346 		mutex_unlock(&port->sep_tg_pt_md_mutex);
1347 	}
1348 
1349 	return 0;
1350 }
1351 
1352 struct t10_alua_lba_map *
core_alua_allocate_lba_map(struct list_head * list,u64 first_lba,u64 last_lba)1353 core_alua_allocate_lba_map(struct list_head *list,
1354 			   u64 first_lba, u64 last_lba)
1355 {
1356 	struct t10_alua_lba_map *lba_map;
1357 
1358 	lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1359 	if (!lba_map) {
1360 		pr_err("Unable to allocate struct t10_alua_lba_map\n");
1361 		return ERR_PTR(-ENOMEM);
1362 	}
1363 	INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1364 	lba_map->lba_map_first_lba = first_lba;
1365 	lba_map->lba_map_last_lba = last_lba;
1366 
1367 	list_add_tail(&lba_map->lba_map_list, list);
1368 	return lba_map;
1369 }
1370 
1371 int
core_alua_allocate_lba_map_mem(struct t10_alua_lba_map * lba_map,int pg_id,int state)1372 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1373 			       int pg_id, int state)
1374 {
1375 	struct t10_alua_lba_map_member *lba_map_mem;
1376 
1377 	list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1378 			    lba_map_mem_list) {
1379 		if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1380 			pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1381 			return -EINVAL;
1382 		}
1383 	}
1384 
1385 	lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1386 	if (!lba_map_mem) {
1387 		pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1388 		return -ENOMEM;
1389 	}
1390 	lba_map_mem->lba_map_mem_alua_state = state;
1391 	lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1392 
1393 	list_add_tail(&lba_map_mem->lba_map_mem_list,
1394 		      &lba_map->lba_map_mem_list);
1395 	return 0;
1396 }
1397 
1398 void
core_alua_free_lba_map(struct list_head * lba_list)1399 core_alua_free_lba_map(struct list_head *lba_list)
1400 {
1401 	struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1402 	struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1403 
1404 	list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1405 				 lba_map_list) {
1406 		list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1407 					 &lba_map->lba_map_mem_list,
1408 					 lba_map_mem_list) {
1409 			list_del(&lba_map_mem->lba_map_mem_list);
1410 			kmem_cache_free(t10_alua_lba_map_mem_cache,
1411 					lba_map_mem);
1412 		}
1413 		list_del(&lba_map->lba_map_list);
1414 		kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1415 	}
1416 }
1417 
1418 void
core_alua_set_lba_map(struct se_device * dev,struct list_head * lba_map_list,int segment_size,int segment_mult)1419 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1420 		      int segment_size, int segment_mult)
1421 {
1422 	struct list_head old_lba_map_list;
1423 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1424 	int activate = 0, supported;
1425 
1426 	INIT_LIST_HEAD(&old_lba_map_list);
1427 	spin_lock(&dev->t10_alua.lba_map_lock);
1428 	dev->t10_alua.lba_map_segment_size = segment_size;
1429 	dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1430 	list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1431 	if (lba_map_list) {
1432 		list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1433 		activate = 1;
1434 	}
1435 	spin_unlock(&dev->t10_alua.lba_map_lock);
1436 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1437 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1438 			    tg_pt_gp_list) {
1439 
1440 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1441 			continue;
1442 		supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1443 		if (activate)
1444 			supported |= ALUA_LBD_SUP;
1445 		else
1446 			supported &= ~ALUA_LBD_SUP;
1447 		tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1448 	}
1449 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1450 	core_alua_free_lba_map(&old_lba_map_list);
1451 }
1452 
1453 struct t10_alua_lu_gp *
core_alua_allocate_lu_gp(const char * name,int def_group)1454 core_alua_allocate_lu_gp(const char *name, int def_group)
1455 {
1456 	struct t10_alua_lu_gp *lu_gp;
1457 
1458 	lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1459 	if (!lu_gp) {
1460 		pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1461 		return ERR_PTR(-ENOMEM);
1462 	}
1463 	INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1464 	INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1465 	spin_lock_init(&lu_gp->lu_gp_lock);
1466 	atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1467 
1468 	if (def_group) {
1469 		lu_gp->lu_gp_id = alua_lu_gps_counter++;
1470 		lu_gp->lu_gp_valid_id = 1;
1471 		alua_lu_gps_count++;
1472 	}
1473 
1474 	return lu_gp;
1475 }
1476 
core_alua_set_lu_gp_id(struct t10_alua_lu_gp * lu_gp,u16 lu_gp_id)1477 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1478 {
1479 	struct t10_alua_lu_gp *lu_gp_tmp;
1480 	u16 lu_gp_id_tmp;
1481 	/*
1482 	 * The lu_gp->lu_gp_id may only be set once..
1483 	 */
1484 	if (lu_gp->lu_gp_valid_id) {
1485 		pr_warn("ALUA LU Group already has a valid ID,"
1486 			" ignoring request\n");
1487 		return -EINVAL;
1488 	}
1489 
1490 	spin_lock(&lu_gps_lock);
1491 	if (alua_lu_gps_count == 0x0000ffff) {
1492 		pr_err("Maximum ALUA alua_lu_gps_count:"
1493 				" 0x0000ffff reached\n");
1494 		spin_unlock(&lu_gps_lock);
1495 		kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1496 		return -ENOSPC;
1497 	}
1498 again:
1499 	lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1500 				alua_lu_gps_counter++;
1501 
1502 	list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1503 		if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1504 			if (!lu_gp_id)
1505 				goto again;
1506 
1507 			pr_warn("ALUA Logical Unit Group ID: %hu"
1508 				" already exists, ignoring request\n",
1509 				lu_gp_id);
1510 			spin_unlock(&lu_gps_lock);
1511 			return -EINVAL;
1512 		}
1513 	}
1514 
1515 	lu_gp->lu_gp_id = lu_gp_id_tmp;
1516 	lu_gp->lu_gp_valid_id = 1;
1517 	list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1518 	alua_lu_gps_count++;
1519 	spin_unlock(&lu_gps_lock);
1520 
1521 	return 0;
1522 }
1523 
1524 static struct t10_alua_lu_gp_member *
core_alua_allocate_lu_gp_mem(struct se_device * dev)1525 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1526 {
1527 	struct t10_alua_lu_gp_member *lu_gp_mem;
1528 
1529 	lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1530 	if (!lu_gp_mem) {
1531 		pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1532 		return ERR_PTR(-ENOMEM);
1533 	}
1534 	INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1535 	spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1536 	atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1537 
1538 	lu_gp_mem->lu_gp_mem_dev = dev;
1539 	dev->dev_alua_lu_gp_mem = lu_gp_mem;
1540 
1541 	return lu_gp_mem;
1542 }
1543 
core_alua_free_lu_gp(struct t10_alua_lu_gp * lu_gp)1544 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1545 {
1546 	struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1547 	/*
1548 	 * Once we have reached this point, config_item_put() has
1549 	 * already been called from target_core_alua_drop_lu_gp().
1550 	 *
1551 	 * Here, we remove the *lu_gp from the global list so that
1552 	 * no associations can be made while we are releasing
1553 	 * struct t10_alua_lu_gp.
1554 	 */
1555 	spin_lock(&lu_gps_lock);
1556 	list_del(&lu_gp->lu_gp_node);
1557 	alua_lu_gps_count--;
1558 	spin_unlock(&lu_gps_lock);
1559 	/*
1560 	 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1561 	 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1562 	 * released with core_alua_put_lu_gp_from_name()
1563 	 */
1564 	while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1565 		cpu_relax();
1566 	/*
1567 	 * Release reference to struct t10_alua_lu_gp * from all associated
1568 	 * struct se_device.
1569 	 */
1570 	spin_lock(&lu_gp->lu_gp_lock);
1571 	list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1572 				&lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1573 		if (lu_gp_mem->lu_gp_assoc) {
1574 			list_del(&lu_gp_mem->lu_gp_mem_list);
1575 			lu_gp->lu_gp_members--;
1576 			lu_gp_mem->lu_gp_assoc = 0;
1577 		}
1578 		spin_unlock(&lu_gp->lu_gp_lock);
1579 		/*
1580 		 *
1581 		 * lu_gp_mem is associated with a single
1582 		 * struct se_device->dev_alua_lu_gp_mem, and is released when
1583 		 * struct se_device is released via core_alua_free_lu_gp_mem().
1584 		 *
1585 		 * If the passed lu_gp does NOT match the default_lu_gp, assume
1586 		 * we want to re-associate a given lu_gp_mem with default_lu_gp.
1587 		 */
1588 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1589 		if (lu_gp != default_lu_gp)
1590 			__core_alua_attach_lu_gp_mem(lu_gp_mem,
1591 					default_lu_gp);
1592 		else
1593 			lu_gp_mem->lu_gp = NULL;
1594 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1595 
1596 		spin_lock(&lu_gp->lu_gp_lock);
1597 	}
1598 	spin_unlock(&lu_gp->lu_gp_lock);
1599 
1600 	kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1601 }
1602 
core_alua_free_lu_gp_mem(struct se_device * dev)1603 void core_alua_free_lu_gp_mem(struct se_device *dev)
1604 {
1605 	struct t10_alua_lu_gp *lu_gp;
1606 	struct t10_alua_lu_gp_member *lu_gp_mem;
1607 
1608 	lu_gp_mem = dev->dev_alua_lu_gp_mem;
1609 	if (!lu_gp_mem)
1610 		return;
1611 
1612 	while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1613 		cpu_relax();
1614 
1615 	spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1616 	lu_gp = lu_gp_mem->lu_gp;
1617 	if (lu_gp) {
1618 		spin_lock(&lu_gp->lu_gp_lock);
1619 		if (lu_gp_mem->lu_gp_assoc) {
1620 			list_del(&lu_gp_mem->lu_gp_mem_list);
1621 			lu_gp->lu_gp_members--;
1622 			lu_gp_mem->lu_gp_assoc = 0;
1623 		}
1624 		spin_unlock(&lu_gp->lu_gp_lock);
1625 		lu_gp_mem->lu_gp = NULL;
1626 	}
1627 	spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1628 
1629 	kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1630 }
1631 
core_alua_get_lu_gp_by_name(const char * name)1632 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1633 {
1634 	struct t10_alua_lu_gp *lu_gp;
1635 	struct config_item *ci;
1636 
1637 	spin_lock(&lu_gps_lock);
1638 	list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1639 		if (!lu_gp->lu_gp_valid_id)
1640 			continue;
1641 		ci = &lu_gp->lu_gp_group.cg_item;
1642 		if (!strcmp(config_item_name(ci), name)) {
1643 			atomic_inc(&lu_gp->lu_gp_ref_cnt);
1644 			spin_unlock(&lu_gps_lock);
1645 			return lu_gp;
1646 		}
1647 	}
1648 	spin_unlock(&lu_gps_lock);
1649 
1650 	return NULL;
1651 }
1652 
core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp * lu_gp)1653 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1654 {
1655 	spin_lock(&lu_gps_lock);
1656 	atomic_dec(&lu_gp->lu_gp_ref_cnt);
1657 	spin_unlock(&lu_gps_lock);
1658 }
1659 
1660 /*
1661  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1662  */
__core_alua_attach_lu_gp_mem(struct t10_alua_lu_gp_member * lu_gp_mem,struct t10_alua_lu_gp * lu_gp)1663 void __core_alua_attach_lu_gp_mem(
1664 	struct t10_alua_lu_gp_member *lu_gp_mem,
1665 	struct t10_alua_lu_gp *lu_gp)
1666 {
1667 	spin_lock(&lu_gp->lu_gp_lock);
1668 	lu_gp_mem->lu_gp = lu_gp;
1669 	lu_gp_mem->lu_gp_assoc = 1;
1670 	list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1671 	lu_gp->lu_gp_members++;
1672 	spin_unlock(&lu_gp->lu_gp_lock);
1673 }
1674 
1675 /*
1676  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1677  */
__core_alua_drop_lu_gp_mem(struct t10_alua_lu_gp_member * lu_gp_mem,struct t10_alua_lu_gp * lu_gp)1678 void __core_alua_drop_lu_gp_mem(
1679 	struct t10_alua_lu_gp_member *lu_gp_mem,
1680 	struct t10_alua_lu_gp *lu_gp)
1681 {
1682 	spin_lock(&lu_gp->lu_gp_lock);
1683 	list_del(&lu_gp_mem->lu_gp_mem_list);
1684 	lu_gp_mem->lu_gp = NULL;
1685 	lu_gp_mem->lu_gp_assoc = 0;
1686 	lu_gp->lu_gp_members--;
1687 	spin_unlock(&lu_gp->lu_gp_lock);
1688 }
1689 
core_alua_allocate_tg_pt_gp(struct se_device * dev,const char * name,int def_group)1690 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1691 		const char *name, int def_group)
1692 {
1693 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1694 
1695 	tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1696 	if (!tg_pt_gp) {
1697 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1698 		return NULL;
1699 	}
1700 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1701 	INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1702 	mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1703 	spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1704 	atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1705 	INIT_DELAYED_WORK(&tg_pt_gp->tg_pt_gp_transition_work,
1706 			  core_alua_do_transition_tg_pt_work);
1707 	tg_pt_gp->tg_pt_gp_dev = dev;
1708 	atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1709 		ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED);
1710 	/*
1711 	 * Enable both explicit and implicit ALUA support by default
1712 	 */
1713 	tg_pt_gp->tg_pt_gp_alua_access_type =
1714 			TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1715 	/*
1716 	 * Set the default Active/NonOptimized Delay in milliseconds
1717 	 */
1718 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1719 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1720 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1721 
1722 	/*
1723 	 * Enable all supported states
1724 	 */
1725 	tg_pt_gp->tg_pt_gp_alua_supported_states =
1726 	    ALUA_T_SUP | ALUA_O_SUP |
1727 	    ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1728 
1729 	if (def_group) {
1730 		spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1731 		tg_pt_gp->tg_pt_gp_id =
1732 				dev->t10_alua.alua_tg_pt_gps_counter++;
1733 		tg_pt_gp->tg_pt_gp_valid_id = 1;
1734 		dev->t10_alua.alua_tg_pt_gps_count++;
1735 		list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1736 			      &dev->t10_alua.tg_pt_gps_list);
1737 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1738 	}
1739 
1740 	return tg_pt_gp;
1741 }
1742 
core_alua_set_tg_pt_gp_id(struct t10_alua_tg_pt_gp * tg_pt_gp,u16 tg_pt_gp_id)1743 int core_alua_set_tg_pt_gp_id(
1744 	struct t10_alua_tg_pt_gp *tg_pt_gp,
1745 	u16 tg_pt_gp_id)
1746 {
1747 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1748 	struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1749 	u16 tg_pt_gp_id_tmp;
1750 
1751 	/*
1752 	 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1753 	 */
1754 	if (tg_pt_gp->tg_pt_gp_valid_id) {
1755 		pr_warn("ALUA TG PT Group already has a valid ID,"
1756 			" ignoring request\n");
1757 		return -EINVAL;
1758 	}
1759 
1760 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1761 	if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1762 		pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1763 			" 0x0000ffff reached\n");
1764 		spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1765 		kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1766 		return -ENOSPC;
1767 	}
1768 again:
1769 	tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1770 			dev->t10_alua.alua_tg_pt_gps_counter++;
1771 
1772 	list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1773 			tg_pt_gp_list) {
1774 		if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1775 			if (!tg_pt_gp_id)
1776 				goto again;
1777 
1778 			pr_err("ALUA Target Port Group ID: %hu already"
1779 				" exists, ignoring request\n", tg_pt_gp_id);
1780 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1781 			return -EINVAL;
1782 		}
1783 	}
1784 
1785 	tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1786 	tg_pt_gp->tg_pt_gp_valid_id = 1;
1787 	list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1788 			&dev->t10_alua.tg_pt_gps_list);
1789 	dev->t10_alua.alua_tg_pt_gps_count++;
1790 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1791 
1792 	return 0;
1793 }
1794 
core_alua_allocate_tg_pt_gp_mem(struct se_port * port)1795 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1796 	struct se_port *port)
1797 {
1798 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1799 
1800 	tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1801 				GFP_KERNEL);
1802 	if (!tg_pt_gp_mem) {
1803 		pr_err("Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1804 		return ERR_PTR(-ENOMEM);
1805 	}
1806 	INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1807 	spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1808 	atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1809 
1810 	tg_pt_gp_mem->tg_pt = port;
1811 	port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1812 
1813 	return tg_pt_gp_mem;
1814 }
1815 
core_alua_free_tg_pt_gp(struct t10_alua_tg_pt_gp * tg_pt_gp)1816 void core_alua_free_tg_pt_gp(
1817 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1818 {
1819 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1820 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1821 
1822 	/*
1823 	 * Once we have reached this point, config_item_put() has already
1824 	 * been called from target_core_alua_drop_tg_pt_gp().
1825 	 *
1826 	 * Here we remove *tg_pt_gp from the global list so that
1827 	 * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1828 	 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1829 	 */
1830 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1831 	list_del(&tg_pt_gp->tg_pt_gp_list);
1832 	dev->t10_alua.alua_tg_pt_gps_counter--;
1833 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1834 
1835 	flush_delayed_work(&tg_pt_gp->tg_pt_gp_transition_work);
1836 
1837 	/*
1838 	 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1839 	 * core_alua_get_tg_pt_gp_by_name() in
1840 	 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1841 	 * to be released with core_alua_put_tg_pt_gp_from_name().
1842 	 */
1843 	while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1844 		cpu_relax();
1845 
1846 	/*
1847 	 * Release reference to struct t10_alua_tg_pt_gp from all associated
1848 	 * struct se_port.
1849 	 */
1850 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1851 	list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1852 			&tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1853 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1854 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1855 			tg_pt_gp->tg_pt_gp_members--;
1856 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1857 		}
1858 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1859 		/*
1860 		 * tg_pt_gp_mem is associated with a single
1861 		 * se_port->sep_alua_tg_pt_gp_mem, and is released via
1862 		 * core_alua_free_tg_pt_gp_mem().
1863 		 *
1864 		 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1865 		 * assume we want to re-associate a given tg_pt_gp_mem with
1866 		 * default_tg_pt_gp.
1867 		 */
1868 		spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1869 		if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1870 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1871 					dev->t10_alua.default_tg_pt_gp);
1872 		} else
1873 			tg_pt_gp_mem->tg_pt_gp = NULL;
1874 		spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1875 
1876 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1877 	}
1878 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1879 
1880 	kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1881 }
1882 
core_alua_free_tg_pt_gp_mem(struct se_port * port)1883 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1884 {
1885 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1886 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1887 
1888 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1889 	if (!tg_pt_gp_mem)
1890 		return;
1891 
1892 	while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1893 		cpu_relax();
1894 
1895 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1896 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1897 	if (tg_pt_gp) {
1898 		spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1899 		if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1900 			list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1901 			tg_pt_gp->tg_pt_gp_members--;
1902 			tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1903 		}
1904 		spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1905 		tg_pt_gp_mem->tg_pt_gp = NULL;
1906 	}
1907 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1908 
1909 	kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1910 }
1911 
core_alua_get_tg_pt_gp_by_name(struct se_device * dev,const char * name)1912 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1913 		struct se_device *dev, const char *name)
1914 {
1915 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1916 	struct config_item *ci;
1917 
1918 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1919 	list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1920 			tg_pt_gp_list) {
1921 		if (!tg_pt_gp->tg_pt_gp_valid_id)
1922 			continue;
1923 		ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1924 		if (!strcmp(config_item_name(ci), name)) {
1925 			atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1926 			spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1927 			return tg_pt_gp;
1928 		}
1929 	}
1930 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1931 
1932 	return NULL;
1933 }
1934 
core_alua_put_tg_pt_gp_from_name(struct t10_alua_tg_pt_gp * tg_pt_gp)1935 static void core_alua_put_tg_pt_gp_from_name(
1936 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1937 {
1938 	struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1939 
1940 	spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1941 	atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1942 	spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1943 }
1944 
1945 /*
1946  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1947  */
__core_alua_attach_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct t10_alua_tg_pt_gp * tg_pt_gp)1948 void __core_alua_attach_tg_pt_gp_mem(
1949 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1950 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1951 {
1952 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1953 	tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1954 	tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1955 	list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1956 			&tg_pt_gp->tg_pt_gp_mem_list);
1957 	tg_pt_gp->tg_pt_gp_members++;
1958 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1959 }
1960 
1961 /*
1962  * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1963  */
__core_alua_drop_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct t10_alua_tg_pt_gp * tg_pt_gp)1964 static void __core_alua_drop_tg_pt_gp_mem(
1965 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1966 	struct t10_alua_tg_pt_gp *tg_pt_gp)
1967 {
1968 	spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1969 	list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1970 	tg_pt_gp_mem->tg_pt_gp = NULL;
1971 	tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1972 	tg_pt_gp->tg_pt_gp_members--;
1973 	spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1974 }
1975 
core_alua_show_tg_pt_gp_info(struct se_port * port,char * page)1976 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1977 {
1978 	struct config_item *tg_pt_ci;
1979 	struct t10_alua_tg_pt_gp *tg_pt_gp;
1980 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1981 	ssize_t len = 0;
1982 
1983 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1984 	if (!tg_pt_gp_mem)
1985 		return len;
1986 
1987 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1988 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1989 	if (tg_pt_gp) {
1990 		tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1991 		len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1992 			" %hu\nTG Port Primary Access State: %s\nTG Port "
1993 			"Primary Access Status: %s\nTG Port Secondary Access"
1994 			" State: %s\nTG Port Secondary Access Status: %s\n",
1995 			config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1996 			core_alua_dump_state(atomic_read(
1997 					&tg_pt_gp->tg_pt_gp_alua_access_state)),
1998 			core_alua_dump_status(
1999 				tg_pt_gp->tg_pt_gp_alua_access_status),
2000 			(atomic_read(&port->sep_tg_pt_secondary_offline)) ?
2001 			"Offline" : "None",
2002 			core_alua_dump_status(port->sep_tg_pt_secondary_stat));
2003 	}
2004 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2005 
2006 	return len;
2007 }
2008 
core_alua_store_tg_pt_gp_info(struct se_port * port,const char * page,size_t count)2009 ssize_t core_alua_store_tg_pt_gp_info(
2010 	struct se_port *port,
2011 	const char *page,
2012 	size_t count)
2013 {
2014 	struct se_portal_group *tpg;
2015 	struct se_lun *lun;
2016 	struct se_device *dev = port->sep_lun->lun_se_dev;
2017 	struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
2018 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2019 	unsigned char buf[TG_PT_GROUP_NAME_BUF];
2020 	int move = 0;
2021 
2022 	tpg = port->sep_tpg;
2023 	lun = port->sep_lun;
2024 
2025 	tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
2026 	if (!tg_pt_gp_mem)
2027 		return 0;
2028 
2029 	if (count > TG_PT_GROUP_NAME_BUF) {
2030 		pr_err("ALUA Target Port Group alias too large!\n");
2031 		return -EINVAL;
2032 	}
2033 	memset(buf, 0, TG_PT_GROUP_NAME_BUF);
2034 	memcpy(buf, page, count);
2035 	/*
2036 	 * Any ALUA target port group alias besides "NULL" means we will be
2037 	 * making a new group association.
2038 	 */
2039 	if (strcmp(strstrip(buf), "NULL")) {
2040 		/*
2041 		 * core_alua_get_tg_pt_gp_by_name() will increment reference to
2042 		 * struct t10_alua_tg_pt_gp.  This reference is released with
2043 		 * core_alua_put_tg_pt_gp_from_name() below.
2044 		 */
2045 		tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
2046 					strstrip(buf));
2047 		if (!tg_pt_gp_new)
2048 			return -ENODEV;
2049 	}
2050 
2051 	spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2052 	tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
2053 	if (tg_pt_gp) {
2054 		/*
2055 		 * Clearing an existing tg_pt_gp association, and replacing
2056 		 * with the default_tg_pt_gp.
2057 		 */
2058 		if (!tg_pt_gp_new) {
2059 			pr_debug("Target_Core_ConfigFS: Moving"
2060 				" %s/tpgt_%hu/%s from ALUA Target Port Group:"
2061 				" alua/%s, ID: %hu back to"
2062 				" default_tg_pt_gp\n",
2063 				tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2064 				tpg->se_tpg_tfo->tpg_get_tag(tpg),
2065 				config_item_name(&lun->lun_group.cg_item),
2066 				config_item_name(
2067 					&tg_pt_gp->tg_pt_gp_group.cg_item),
2068 				tg_pt_gp->tg_pt_gp_id);
2069 
2070 			__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2071 			__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
2072 					dev->t10_alua.default_tg_pt_gp);
2073 			spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2074 
2075 			return count;
2076 		}
2077 		/*
2078 		 * Removing existing association of tg_pt_gp_mem with tg_pt_gp
2079 		 */
2080 		__core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
2081 		move = 1;
2082 	}
2083 	/*
2084 	 * Associate tg_pt_gp_mem with tg_pt_gp_new.
2085 	 */
2086 	__core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
2087 	spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
2088 	pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
2089 		" Target Port Group: alua/%s, ID: %hu\n", (move) ?
2090 		"Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
2091 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
2092 		config_item_name(&lun->lun_group.cg_item),
2093 		config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
2094 		tg_pt_gp_new->tg_pt_gp_id);
2095 
2096 	core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
2097 	return count;
2098 }
2099 
core_alua_show_access_type(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2100 ssize_t core_alua_show_access_type(
2101 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2102 	char *page)
2103 {
2104 	if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
2105 	    (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
2106 		return sprintf(page, "Implicit and Explicit\n");
2107 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
2108 		return sprintf(page, "Implicit\n");
2109 	else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
2110 		return sprintf(page, "Explicit\n");
2111 	else
2112 		return sprintf(page, "None\n");
2113 }
2114 
core_alua_store_access_type(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2115 ssize_t core_alua_store_access_type(
2116 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2117 	const char *page,
2118 	size_t count)
2119 {
2120 	unsigned long tmp;
2121 	int ret;
2122 
2123 	ret = kstrtoul(page, 0, &tmp);
2124 	if (ret < 0) {
2125 		pr_err("Unable to extract alua_access_type\n");
2126 		return ret;
2127 	}
2128 	if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2129 		pr_err("Illegal value for alua_access_type:"
2130 				" %lu\n", tmp);
2131 		return -EINVAL;
2132 	}
2133 	if (tmp == 3)
2134 		tg_pt_gp->tg_pt_gp_alua_access_type =
2135 			TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2136 	else if (tmp == 2)
2137 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2138 	else if (tmp == 1)
2139 		tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2140 	else
2141 		tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2142 
2143 	return count;
2144 }
2145 
core_alua_show_nonop_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2146 ssize_t core_alua_show_nonop_delay_msecs(
2147 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2148 	char *page)
2149 {
2150 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2151 }
2152 
core_alua_store_nonop_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2153 ssize_t core_alua_store_nonop_delay_msecs(
2154 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2155 	const char *page,
2156 	size_t count)
2157 {
2158 	unsigned long tmp;
2159 	int ret;
2160 
2161 	ret = kstrtoul(page, 0, &tmp);
2162 	if (ret < 0) {
2163 		pr_err("Unable to extract nonop_delay_msecs\n");
2164 		return ret;
2165 	}
2166 	if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2167 		pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2168 			" ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2169 			ALUA_MAX_NONOP_DELAY_MSECS);
2170 		return -EINVAL;
2171 	}
2172 	tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2173 
2174 	return count;
2175 }
2176 
core_alua_show_trans_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2177 ssize_t core_alua_show_trans_delay_msecs(
2178 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2179 	char *page)
2180 {
2181 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2182 }
2183 
core_alua_store_trans_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2184 ssize_t core_alua_store_trans_delay_msecs(
2185 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2186 	const char *page,
2187 	size_t count)
2188 {
2189 	unsigned long tmp;
2190 	int ret;
2191 
2192 	ret = kstrtoul(page, 0, &tmp);
2193 	if (ret < 0) {
2194 		pr_err("Unable to extract trans_delay_msecs\n");
2195 		return ret;
2196 	}
2197 	if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2198 		pr_err("Passed trans_delay_msecs: %lu, exceeds"
2199 			" ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2200 			ALUA_MAX_TRANS_DELAY_MSECS);
2201 		return -EINVAL;
2202 	}
2203 	tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2204 
2205 	return count;
2206 }
2207 
core_alua_show_implicit_trans_secs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2208 ssize_t core_alua_show_implicit_trans_secs(
2209 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2210 	char *page)
2211 {
2212 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2213 }
2214 
core_alua_store_implicit_trans_secs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2215 ssize_t core_alua_store_implicit_trans_secs(
2216 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2217 	const char *page,
2218 	size_t count)
2219 {
2220 	unsigned long tmp;
2221 	int ret;
2222 
2223 	ret = kstrtoul(page, 0, &tmp);
2224 	if (ret < 0) {
2225 		pr_err("Unable to extract implicit_trans_secs\n");
2226 		return ret;
2227 	}
2228 	if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2229 		pr_err("Passed implicit_trans_secs: %lu, exceeds"
2230 			" ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2231 			ALUA_MAX_IMPLICIT_TRANS_SECS);
2232 		return  -EINVAL;
2233 	}
2234 	tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2235 
2236 	return count;
2237 }
2238 
core_alua_show_preferred_bit(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)2239 ssize_t core_alua_show_preferred_bit(
2240 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2241 	char *page)
2242 {
2243 	return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2244 }
2245 
core_alua_store_preferred_bit(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)2246 ssize_t core_alua_store_preferred_bit(
2247 	struct t10_alua_tg_pt_gp *tg_pt_gp,
2248 	const char *page,
2249 	size_t count)
2250 {
2251 	unsigned long tmp;
2252 	int ret;
2253 
2254 	ret = kstrtoul(page, 0, &tmp);
2255 	if (ret < 0) {
2256 		pr_err("Unable to extract preferred ALUA value\n");
2257 		return ret;
2258 	}
2259 	if ((tmp != 0) && (tmp != 1)) {
2260 		pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2261 		return -EINVAL;
2262 	}
2263 	tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2264 
2265 	return count;
2266 }
2267 
core_alua_show_offline_bit(struct se_lun * lun,char * page)2268 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2269 {
2270 	if (!lun->lun_sep)
2271 		return -ENODEV;
2272 
2273 	return sprintf(page, "%d\n",
2274 		atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
2275 }
2276 
core_alua_store_offline_bit(struct se_lun * lun,const char * page,size_t count)2277 ssize_t core_alua_store_offline_bit(
2278 	struct se_lun *lun,
2279 	const char *page,
2280 	size_t count)
2281 {
2282 	struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
2283 	unsigned long tmp;
2284 	int ret;
2285 
2286 	if (!lun->lun_sep)
2287 		return -ENODEV;
2288 
2289 	ret = kstrtoul(page, 0, &tmp);
2290 	if (ret < 0) {
2291 		pr_err("Unable to extract alua_tg_pt_offline value\n");
2292 		return ret;
2293 	}
2294 	if ((tmp != 0) && (tmp != 1)) {
2295 		pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2296 				tmp);
2297 		return -EINVAL;
2298 	}
2299 	tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
2300 	if (!tg_pt_gp_mem) {
2301 		pr_err("Unable to locate *tg_pt_gp_mem\n");
2302 		return -EINVAL;
2303 	}
2304 
2305 	ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
2306 			lun->lun_sep, 0, (int)tmp);
2307 	if (ret < 0)
2308 		return -EINVAL;
2309 
2310 	return count;
2311 }
2312 
core_alua_show_secondary_status(struct se_lun * lun,char * page)2313 ssize_t core_alua_show_secondary_status(
2314 	struct se_lun *lun,
2315 	char *page)
2316 {
2317 	return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
2318 }
2319 
core_alua_store_secondary_status(struct se_lun * lun,const char * page,size_t count)2320 ssize_t core_alua_store_secondary_status(
2321 	struct se_lun *lun,
2322 	const char *page,
2323 	size_t count)
2324 {
2325 	unsigned long tmp;
2326 	int ret;
2327 
2328 	ret = kstrtoul(page, 0, &tmp);
2329 	if (ret < 0) {
2330 		pr_err("Unable to extract alua_tg_pt_status\n");
2331 		return ret;
2332 	}
2333 	if ((tmp != ALUA_STATUS_NONE) &&
2334 	    (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2335 	    (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2336 		pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2337 				tmp);
2338 		return -EINVAL;
2339 	}
2340 	lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
2341 
2342 	return count;
2343 }
2344 
core_alua_show_secondary_write_metadata(struct se_lun * lun,char * page)2345 ssize_t core_alua_show_secondary_write_metadata(
2346 	struct se_lun *lun,
2347 	char *page)
2348 {
2349 	return sprintf(page, "%d\n",
2350 			lun->lun_sep->sep_tg_pt_secondary_write_md);
2351 }
2352 
core_alua_store_secondary_write_metadata(struct se_lun * lun,const char * page,size_t count)2353 ssize_t core_alua_store_secondary_write_metadata(
2354 	struct se_lun *lun,
2355 	const char *page,
2356 	size_t count)
2357 {
2358 	unsigned long tmp;
2359 	int ret;
2360 
2361 	ret = kstrtoul(page, 0, &tmp);
2362 	if (ret < 0) {
2363 		pr_err("Unable to extract alua_tg_pt_write_md\n");
2364 		return ret;
2365 	}
2366 	if ((tmp != 0) && (tmp != 1)) {
2367 		pr_err("Illegal value for alua_tg_pt_write_md:"
2368 				" %lu\n", tmp);
2369 		return -EINVAL;
2370 	}
2371 	lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
2372 
2373 	return count;
2374 }
2375 
core_setup_alua(struct se_device * dev)2376 int core_setup_alua(struct se_device *dev)
2377 {
2378 	if (dev->transport->transport_type != TRANSPORT_PLUGIN_PHBA_PDEV &&
2379 	    !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2380 		struct t10_alua_lu_gp_member *lu_gp_mem;
2381 
2382 		/*
2383 		 * Associate this struct se_device with the default ALUA
2384 		 * LUN Group.
2385 		 */
2386 		lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2387 		if (IS_ERR(lu_gp_mem))
2388 			return PTR_ERR(lu_gp_mem);
2389 
2390 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2391 		__core_alua_attach_lu_gp_mem(lu_gp_mem,
2392 				default_lu_gp);
2393 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2394 
2395 		pr_debug("%s: Adding to default ALUA LU Group:"
2396 			" core/alua/lu_gps/default_lu_gp\n",
2397 			dev->transport->name);
2398 	}
2399 
2400 	return 0;
2401 }
2402