GNU Linux-libre 6.9.1-gnu
[releases.git] / drivers / target / target_core_alua.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * Filename:  target_core_alua.c
4  *
5  * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
6  *
7  * (c) Copyright 2009-2013 Datera, Inc.
8  *
9  * Nicholas A. Bellinger <nab@kernel.org>
10  *
11  ******************************************************************************/
12
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 #include <linux/configfs.h>
16 #include <linux/delay.h>
17 #include <linux/export.h>
18 #include <linux/fcntl.h>
19 #include <linux/file.h>
20 #include <linux/fs.h>
21 #include <scsi/scsi_proto.h>
22 #include <asm/unaligned.h>
23
24 #include <target/target_core_base.h>
25 #include <target/target_core_backend.h>
26 #include <target/target_core_fabric.h>
27
28 #include "target_core_internal.h"
29 #include "target_core_alua.h"
30 #include "target_core_ua.h"
31
32 static sense_reason_t core_alua_check_transition(int state, int valid,
33                                                  int *primary, int explicit);
34 static int core_alua_set_tg_pt_secondary_state(
35                 struct se_lun *lun, int explicit, int offline);
36
37 static char *core_alua_dump_state(int state);
38
39 static void __target_attach_tg_pt_gp(struct se_lun *lun,
40                 struct t10_alua_tg_pt_gp *tg_pt_gp);
41
42 static u16 alua_lu_gps_counter;
43 static u32 alua_lu_gps_count;
44
45 static DEFINE_SPINLOCK(lu_gps_lock);
46 static LIST_HEAD(lu_gps_list);
47
48 struct t10_alua_lu_gp *default_lu_gp;
49
50 /*
51  * REPORT REFERRALS
52  *
53  * See sbc3r35 section 5.23
54  */
55 sense_reason_t
56 target_emulate_report_referrals(struct se_cmd *cmd)
57 {
58         struct se_device *dev = cmd->se_dev;
59         struct t10_alua_lba_map *map;
60         struct t10_alua_lba_map_member *map_mem;
61         unsigned char *buf;
62         u32 rd_len = 0, off;
63
64         if (cmd->data_length < 4) {
65                 pr_warn("REPORT REFERRALS allocation length %u too"
66                         " small\n", cmd->data_length);
67                 return TCM_INVALID_CDB_FIELD;
68         }
69
70         buf = transport_kmap_data_sg(cmd);
71         if (!buf)
72                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
73
74         off = 4;
75         spin_lock(&dev->t10_alua.lba_map_lock);
76         if (list_empty(&dev->t10_alua.lba_map_list)) {
77                 spin_unlock(&dev->t10_alua.lba_map_lock);
78                 transport_kunmap_data_sg(cmd);
79
80                 return TCM_UNSUPPORTED_SCSI_OPCODE;
81         }
82
83         list_for_each_entry(map, &dev->t10_alua.lba_map_list,
84                             lba_map_list) {
85                 int desc_num = off + 3;
86                 int pg_num;
87
88                 off += 4;
89                 if (cmd->data_length > off)
90                         put_unaligned_be64(map->lba_map_first_lba, &buf[off]);
91                 off += 8;
92                 if (cmd->data_length > off)
93                         put_unaligned_be64(map->lba_map_last_lba, &buf[off]);
94                 off += 8;
95                 rd_len += 20;
96                 pg_num = 0;
97                 list_for_each_entry(map_mem, &map->lba_map_mem_list,
98                                     lba_map_mem_list) {
99                         int alua_state = map_mem->lba_map_mem_alua_state;
100                         int alua_pg_id = map_mem->lba_map_mem_alua_pg_id;
101
102                         if (cmd->data_length > off)
103                                 buf[off] = alua_state & 0x0f;
104                         off += 2;
105                         if (cmd->data_length > off)
106                                 buf[off] = (alua_pg_id >> 8) & 0xff;
107                         off++;
108                         if (cmd->data_length > off)
109                                 buf[off] = (alua_pg_id & 0xff);
110                         off++;
111                         rd_len += 4;
112                         pg_num++;
113                 }
114                 if (cmd->data_length > desc_num)
115                         buf[desc_num] = pg_num;
116         }
117         spin_unlock(&dev->t10_alua.lba_map_lock);
118
119         /*
120          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
121          */
122         put_unaligned_be16(rd_len, &buf[2]);
123
124         transport_kunmap_data_sg(cmd);
125
126         target_complete_cmd(cmd, SAM_STAT_GOOD);
127         return 0;
128 }
129
130 /*
131  * REPORT_TARGET_PORT_GROUPS
132  *
133  * See spc4r17 section 6.27
134  */
135 sense_reason_t
136 target_emulate_report_target_port_groups(struct se_cmd *cmd)
137 {
138         struct se_device *dev = cmd->se_dev;
139         struct t10_alua_tg_pt_gp *tg_pt_gp;
140         struct se_lun *lun;
141         unsigned char *buf;
142         u32 rd_len = 0, off;
143         int ext_hdr = (cmd->t_task_cdb[1] & 0x20);
144
145         /*
146          * Skip over RESERVED area to first Target port group descriptor
147          * depending on the PARAMETER DATA FORMAT type..
148          */
149         if (ext_hdr != 0)
150                 off = 8;
151         else
152                 off = 4;
153
154         if (cmd->data_length < off) {
155                 pr_warn("REPORT TARGET PORT GROUPS allocation length %u too"
156                         " small for %s header\n", cmd->data_length,
157                         (ext_hdr) ? "extended" : "normal");
158                 return TCM_INVALID_CDB_FIELD;
159         }
160         buf = transport_kmap_data_sg(cmd);
161         if (!buf)
162                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
163
164         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
165         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
166                         tg_pt_gp_list) {
167                 /* Skip empty port groups */
168                 if (!tg_pt_gp->tg_pt_gp_members)
169                         continue;
170                 /*
171                  * Check if the Target port group and Target port descriptor list
172                  * based on tg_pt_gp_members count will fit into the response payload.
173                  * Otherwise, bump rd_len to let the initiator know we have exceeded
174                  * the allocation length and the response is truncated.
175                  */
176                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
177                      cmd->data_length) {
178                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
179                         continue;
180                 }
181                 /*
182                  * PREF: Preferred target port bit, determine if this
183                  * bit should be set for port group.
184                  */
185                 if (tg_pt_gp->tg_pt_gp_pref)
186                         buf[off] = 0x80;
187                 /*
188                  * Set the ASYMMETRIC ACCESS State
189                  */
190                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_access_state & 0xff;
191                 /*
192                  * Set supported ASYMMETRIC ACCESS State bits
193                  */
194                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
195                 /*
196                  * TARGET PORT GROUP
197                  */
198                 put_unaligned_be16(tg_pt_gp->tg_pt_gp_id, &buf[off]);
199                 off += 2;
200
201                 off++; /* Skip over Reserved */
202                 /*
203                  * STATUS CODE
204                  */
205                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
206                 /*
207                  * Vendor Specific field
208                  */
209                 buf[off++] = 0x00;
210                 /*
211                  * TARGET PORT COUNT
212                  */
213                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
214                 rd_len += 8;
215
216                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
217                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
218                                 lun_tg_pt_gp_link) {
219                         /*
220                          * Start Target Port descriptor format
221                          *
222                          * See spc4r17 section 6.2.7 Table 247
223                          */
224                         off += 2; /* Skip over Obsolete */
225                         /*
226                          * Set RELATIVE TARGET PORT IDENTIFIER
227                          */
228                         put_unaligned_be16(lun->lun_tpg->tpg_rtpi, &buf[off]);
229                         off += 2;
230                         rd_len += 4;
231                 }
232                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
233         }
234         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
235         /*
236          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
237          */
238         put_unaligned_be32(rd_len, &buf[0]);
239
240         /*
241          * Fill in the Extended header parameter data format if requested
242          */
243         if (ext_hdr != 0) {
244                 buf[4] = 0x10;
245                 /*
246                  * Set the implicit transition time (in seconds) for the application
247                  * client to use as a base for it's transition timeout value.
248                  *
249                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
250                  * this CDB was received upon to determine this value individually
251                  * for ALUA target port group.
252                  */
253                 rcu_read_lock();
254                 tg_pt_gp = rcu_dereference(cmd->se_lun->lun_tg_pt_gp);
255                 if (tg_pt_gp)
256                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
257                 rcu_read_unlock();
258         }
259         transport_kunmap_data_sg(cmd);
260
261         target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, rd_len + 4);
262         return 0;
263 }
264
265 /*
266  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
267  *
268  * See spc4r17 section 6.35
269  */
270 sense_reason_t
271 target_emulate_set_target_port_groups(struct se_cmd *cmd)
272 {
273         struct se_device *dev = cmd->se_dev;
274         struct se_lun *l_lun = cmd->se_lun;
275         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
276         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
277         unsigned char *buf;
278         unsigned char *ptr;
279         sense_reason_t rc = TCM_NO_SENSE;
280         u32 len = 4; /* Skip over RESERVED area in header */
281         int alua_access_state, primary = 0, valid_states;
282         u16 tg_pt_id, rtpi;
283
284         if (cmd->data_length < 4) {
285                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
286                         " small\n", cmd->data_length);
287                 return TCM_INVALID_PARAMETER_LIST;
288         }
289
290         buf = transport_kmap_data_sg(cmd);
291         if (!buf)
292                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
293
294         /*
295          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
296          * for the local tg_pt_gp.
297          */
298         rcu_read_lock();
299         l_tg_pt_gp = rcu_dereference(l_lun->lun_tg_pt_gp);
300         if (!l_tg_pt_gp) {
301                 rcu_read_unlock();
302                 pr_err("Unable to access l_lun->tg_pt_gp\n");
303                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
304                 goto out;
305         }
306
307         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
308                 rcu_read_unlock();
309                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
310                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
311                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
312                 goto out;
313         }
314         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
315         rcu_read_unlock();
316
317         ptr = &buf[4]; /* Skip over RESERVED area in header */
318
319         while (len < cmd->data_length) {
320                 bool found = false;
321                 alua_access_state = (ptr[0] & 0x0f);
322                 /*
323                  * Check the received ALUA access state, and determine if
324                  * the state is a primary or secondary target port asymmetric
325                  * access state.
326                  */
327                 rc = core_alua_check_transition(alua_access_state, valid_states,
328                                                 &primary, 1);
329                 if (rc) {
330                         /*
331                          * If the SET TARGET PORT GROUPS attempts to establish
332                          * an invalid combination of target port asymmetric
333                          * access states or attempts to establish an
334                          * unsupported target port asymmetric access state,
335                          * then the command shall be terminated with CHECK
336                          * CONDITION status, with the sense key set to ILLEGAL
337                          * REQUEST, and the additional sense code set to INVALID
338                          * FIELD IN PARAMETER LIST.
339                          */
340                         goto out;
341                 }
342
343                 /*
344                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
345                  * specifies a primary target port asymmetric access state,
346                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
347                  * a primary target port group for which the primary target
348                  * port asymmetric access state shall be changed. If the
349                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
350                  * port asymmetric access state, then the TARGET PORT GROUP OR
351                  * TARGET PORT field specifies the relative target port
352                  * identifier (see 3.1.120) of the target port for which the
353                  * secondary target port asymmetric access state shall be
354                  * changed.
355                  */
356                 if (primary) {
357                         tg_pt_id = get_unaligned_be16(ptr + 2);
358                         /*
359                          * Locate the matching target port group ID from
360                          * the global tg_pt_gp list
361                          */
362                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
363                         list_for_each_entry(tg_pt_gp,
364                                         &dev->t10_alua.tg_pt_gps_list,
365                                         tg_pt_gp_list) {
366                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
367                                         continue;
368
369                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
370                                         continue;
371
372                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
373
374                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
375
376                                 if (!core_alua_do_port_transition(tg_pt_gp,
377                                                 dev, l_lun, nacl,
378                                                 alua_access_state, 1))
379                                         found = true;
380
381                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
382                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
383                                 break;
384                         }
385                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
386                 } else {
387                         struct se_lun *lun;
388
389                         /*
390                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
391                          * the Target Port in question for the incoming
392                          * SET_TARGET_PORT_GROUPS op.
393                          */
394                         rtpi = get_unaligned_be16(ptr + 2);
395                         /*
396                          * Locate the matching relative target port identifier
397                          * for the struct se_device storage object.
398                          */
399                         spin_lock(&dev->se_port_lock);
400                         list_for_each_entry(lun, &dev->dev_sep_list,
401                                                         lun_dev_link) {
402                                 if (lun->lun_tpg->tpg_rtpi != rtpi)
403                                         continue;
404
405                                 // XXX: racy unlock
406                                 spin_unlock(&dev->se_port_lock);
407
408                                 if (!core_alua_set_tg_pt_secondary_state(
409                                                 lun, 1, 1))
410                                         found = true;
411
412                                 spin_lock(&dev->se_port_lock);
413                                 break;
414                         }
415                         spin_unlock(&dev->se_port_lock);
416                 }
417
418                 if (!found) {
419                         rc = TCM_INVALID_PARAMETER_LIST;
420                         goto out;
421                 }
422
423                 ptr += 4;
424                 len += 4;
425         }
426
427 out:
428         transport_kunmap_data_sg(cmd);
429         if (!rc)
430                 target_complete_cmd(cmd, SAM_STAT_GOOD);
431         return rc;
432 }
433
434 static inline void core_alua_state_nonoptimized(
435         struct se_cmd *cmd,
436         unsigned char *cdb,
437         int nonop_delay_msecs)
438 {
439         /*
440          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
441          * later to determine if processing of this cmd needs to be
442          * temporarily delayed for the Active/NonOptimized primary access state.
443          */
444         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
445         cmd->alua_nonop_delay = nonop_delay_msecs;
446 }
447
448 static inline sense_reason_t core_alua_state_lba_dependent(
449         struct se_cmd *cmd,
450         u16 tg_pt_gp_id)
451 {
452         struct se_device *dev = cmd->se_dev;
453         u64 segment_size, segment_mult, sectors, lba;
454
455         /* Only need to check for cdb actually containing LBAs */
456         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
457                 return 0;
458
459         spin_lock(&dev->t10_alua.lba_map_lock);
460         segment_size = dev->t10_alua.lba_map_segment_size;
461         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
462         sectors = cmd->data_length / dev->dev_attrib.block_size;
463
464         lba = cmd->t_task_lba;
465         while (lba < cmd->t_task_lba + sectors) {
466                 struct t10_alua_lba_map *cur_map = NULL, *map;
467                 struct t10_alua_lba_map_member *map_mem;
468
469                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
470                                     lba_map_list) {
471                         u64 start_lba, last_lba;
472                         u64 first_lba = map->lba_map_first_lba;
473
474                         if (segment_mult) {
475                                 u64 tmp = lba;
476                                 start_lba = do_div(tmp, segment_size * segment_mult);
477
478                                 last_lba = first_lba + segment_size - 1;
479                                 if (start_lba >= first_lba &&
480                                     start_lba <= last_lba) {
481                                         lba += segment_size;
482                                         cur_map = map;
483                                         break;
484                                 }
485                         } else {
486                                 last_lba = map->lba_map_last_lba;
487                                 if (lba >= first_lba && lba <= last_lba) {
488                                         lba = last_lba + 1;
489                                         cur_map = map;
490                                         break;
491                                 }
492                         }
493                 }
494                 if (!cur_map) {
495                         spin_unlock(&dev->t10_alua.lba_map_lock);
496                         return TCM_ALUA_TG_PT_UNAVAILABLE;
497                 }
498                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
499                                     lba_map_mem_list) {
500                         if (map_mem->lba_map_mem_alua_pg_id != tg_pt_gp_id)
501                                 continue;
502                         switch(map_mem->lba_map_mem_alua_state) {
503                         case ALUA_ACCESS_STATE_STANDBY:
504                                 spin_unlock(&dev->t10_alua.lba_map_lock);
505                                 return TCM_ALUA_TG_PT_STANDBY;
506                         case ALUA_ACCESS_STATE_UNAVAILABLE:
507                                 spin_unlock(&dev->t10_alua.lba_map_lock);
508                                 return TCM_ALUA_TG_PT_UNAVAILABLE;
509                         default:
510                                 break;
511                         }
512                 }
513         }
514         spin_unlock(&dev->t10_alua.lba_map_lock);
515         return 0;
516 }
517
518 static inline sense_reason_t core_alua_state_standby(
519         struct se_cmd *cmd,
520         unsigned char *cdb)
521 {
522         /*
523          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
524          * spc4r17 section 5.9.2.4.4
525          */
526         switch (cdb[0]) {
527         case INQUIRY:
528         case LOG_SELECT:
529         case LOG_SENSE:
530         case MODE_SELECT:
531         case MODE_SENSE:
532         case REPORT_LUNS:
533         case RECEIVE_DIAGNOSTIC:
534         case SEND_DIAGNOSTIC:
535         case READ_CAPACITY:
536                 return 0;
537         case SERVICE_ACTION_IN_16:
538                 switch (cdb[1] & 0x1f) {
539                 case SAI_READ_CAPACITY_16:
540                         return 0;
541                 default:
542                         return TCM_ALUA_TG_PT_STANDBY;
543                 }
544         case MAINTENANCE_IN:
545                 switch (cdb[1] & 0x1f) {
546                 case MI_REPORT_TARGET_PGS:
547                         return 0;
548                 default:
549                         return TCM_ALUA_TG_PT_STANDBY;
550                 }
551         case MAINTENANCE_OUT:
552                 switch (cdb[1]) {
553                 case MO_SET_TARGET_PGS:
554                         return 0;
555                 default:
556                         return TCM_ALUA_TG_PT_STANDBY;
557                 }
558         case REQUEST_SENSE:
559         case PERSISTENT_RESERVE_IN:
560         case PERSISTENT_RESERVE_OUT:
561         case READ_BUFFER:
562         case WRITE_BUFFER:
563                 return 0;
564         default:
565                 return TCM_ALUA_TG_PT_STANDBY;
566         }
567
568         return 0;
569 }
570
571 static inline sense_reason_t core_alua_state_unavailable(
572         struct se_cmd *cmd,
573         unsigned char *cdb)
574 {
575         /*
576          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
577          * spc4r17 section 5.9.2.4.5
578          */
579         switch (cdb[0]) {
580         case INQUIRY:
581         case REPORT_LUNS:
582                 return 0;
583         case MAINTENANCE_IN:
584                 switch (cdb[1] & 0x1f) {
585                 case MI_REPORT_TARGET_PGS:
586                         return 0;
587                 default:
588                         return TCM_ALUA_TG_PT_UNAVAILABLE;
589                 }
590         case MAINTENANCE_OUT:
591                 switch (cdb[1]) {
592                 case MO_SET_TARGET_PGS:
593                         return 0;
594                 default:
595                         return TCM_ALUA_TG_PT_UNAVAILABLE;
596                 }
597         case REQUEST_SENSE:
598         case READ_BUFFER:
599         case WRITE_BUFFER:
600                 return 0;
601         default:
602                 return TCM_ALUA_TG_PT_UNAVAILABLE;
603         }
604
605         return 0;
606 }
607
608 static inline sense_reason_t core_alua_state_transition(
609         struct se_cmd *cmd,
610         unsigned char *cdb)
611 {
612         /*
613          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
614          * spc4r17 section 5.9.2.5
615          */
616         switch (cdb[0]) {
617         case INQUIRY:
618         case REPORT_LUNS:
619                 return 0;
620         case MAINTENANCE_IN:
621                 switch (cdb[1] & 0x1f) {
622                 case MI_REPORT_TARGET_PGS:
623                         return 0;
624                 default:
625                         return TCM_ALUA_STATE_TRANSITION;
626                 }
627         case REQUEST_SENSE:
628         case READ_BUFFER:
629         case WRITE_BUFFER:
630                 return 0;
631         default:
632                 return TCM_ALUA_STATE_TRANSITION;
633         }
634
635         return 0;
636 }
637
638 /*
639  * return 1: Is used to signal LUN not accessible, and check condition/not ready
640  * return 0: Used to signal success
641  * return -1: Used to signal failure, and invalid cdb field
642  */
643 sense_reason_t
644 target_alua_state_check(struct se_cmd *cmd)
645 {
646         struct se_device *dev = cmd->se_dev;
647         unsigned char *cdb = cmd->t_task_cdb;
648         struct se_lun *lun = cmd->se_lun;
649         struct t10_alua_tg_pt_gp *tg_pt_gp;
650         int out_alua_state, nonop_delay_msecs;
651         u16 tg_pt_gp_id;
652         sense_reason_t rc = TCM_NO_SENSE;
653
654         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
655                 return 0;
656         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
657                 return 0;
658
659         /*
660          * First, check for a struct se_port specific secondary ALUA target port
661          * access state: OFFLINE
662          */
663         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
664                 pr_debug("ALUA: Got secondary offline status for local"
665                                 " target port\n");
666                 return TCM_ALUA_OFFLINE;
667         }
668         rcu_read_lock();
669         tg_pt_gp = rcu_dereference(lun->lun_tg_pt_gp);
670         if (!tg_pt_gp) {
671                 rcu_read_unlock();
672                 return 0;
673         }
674
675         out_alua_state = tg_pt_gp->tg_pt_gp_alua_access_state;
676         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
677         tg_pt_gp_id = tg_pt_gp->tg_pt_gp_id;
678         rcu_read_unlock();
679         /*
680          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
681          * statement so the compiler knows explicitly to check this case first.
682          * For the Optimized ALUA access state case, we want to process the
683          * incoming fabric cmd ASAP..
684          */
685         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
686                 return 0;
687
688         switch (out_alua_state) {
689         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
690                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
691                 break;
692         case ALUA_ACCESS_STATE_STANDBY:
693                 rc = core_alua_state_standby(cmd, cdb);
694                 break;
695         case ALUA_ACCESS_STATE_UNAVAILABLE:
696                 rc = core_alua_state_unavailable(cmd, cdb);
697                 break;
698         case ALUA_ACCESS_STATE_TRANSITION:
699                 rc = core_alua_state_transition(cmd, cdb);
700                 break;
701         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
702                 rc = core_alua_state_lba_dependent(cmd, tg_pt_gp_id);
703                 break;
704         /*
705          * OFFLINE is a secondary ALUA target port group access state, that is
706          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
707          */
708         case ALUA_ACCESS_STATE_OFFLINE:
709         default:
710                 pr_err("Unknown ALUA access state: 0x%02x\n",
711                                 out_alua_state);
712                 rc = TCM_INVALID_CDB_FIELD;
713         }
714
715         if (rc && rc != TCM_INVALID_CDB_FIELD) {
716                 pr_debug("[%s]: ALUA TG Port not available, "
717                         "SenseKey: NOT_READY, ASC/rc: 0x04/%d\n",
718                         cmd->se_tfo->fabric_name, rc);
719         }
720
721         return rc;
722 }
723
724 /*
725  * Check implicit and explicit ALUA state change request.
726  */
727 static sense_reason_t
728 core_alua_check_transition(int state, int valid, int *primary, int explicit)
729 {
730         /*
731          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
732          * defined as primary target port asymmetric access states.
733          */
734         switch (state) {
735         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
736                 if (!(valid & ALUA_AO_SUP))
737                         goto not_supported;
738                 *primary = 1;
739                 break;
740         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
741                 if (!(valid & ALUA_AN_SUP))
742                         goto not_supported;
743                 *primary = 1;
744                 break;
745         case ALUA_ACCESS_STATE_STANDBY:
746                 if (!(valid & ALUA_S_SUP))
747                         goto not_supported;
748                 *primary = 1;
749                 break;
750         case ALUA_ACCESS_STATE_UNAVAILABLE:
751                 if (!(valid & ALUA_U_SUP))
752                         goto not_supported;
753                 *primary = 1;
754                 break;
755         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
756                 if (!(valid & ALUA_LBD_SUP))
757                         goto not_supported;
758                 *primary = 1;
759                 break;
760         case ALUA_ACCESS_STATE_OFFLINE:
761                 /*
762                  * OFFLINE state is defined as a secondary target port
763                  * asymmetric access state.
764                  */
765                 if (!(valid & ALUA_O_SUP))
766                         goto not_supported;
767                 *primary = 0;
768                 break;
769         case ALUA_ACCESS_STATE_TRANSITION:
770                 if (!(valid & ALUA_T_SUP) || explicit)
771                         /*
772                          * Transitioning is set internally and by tcmu daemon,
773                          * and cannot be selected through a STPG.
774                          */
775                         goto not_supported;
776                 *primary = 0;
777                 break;
778         default:
779                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
780                 return TCM_INVALID_PARAMETER_LIST;
781         }
782
783         return 0;
784
785 not_supported:
786         pr_err("ALUA access state %s not supported",
787                core_alua_dump_state(state));
788         return TCM_INVALID_PARAMETER_LIST;
789 }
790
791 static char *core_alua_dump_state(int state)
792 {
793         switch (state) {
794         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
795                 return "Active/Optimized";
796         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
797                 return "Active/NonOptimized";
798         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
799                 return "LBA Dependent";
800         case ALUA_ACCESS_STATE_STANDBY:
801                 return "Standby";
802         case ALUA_ACCESS_STATE_UNAVAILABLE:
803                 return "Unavailable";
804         case ALUA_ACCESS_STATE_OFFLINE:
805                 return "Offline";
806         case ALUA_ACCESS_STATE_TRANSITION:
807                 return "Transitioning";
808         default:
809                 return "Unknown";
810         }
811
812         return NULL;
813 }
814
815 char *core_alua_dump_status(int status)
816 {
817         switch (status) {
818         case ALUA_STATUS_NONE:
819                 return "None";
820         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
821                 return "Altered by Explicit STPG";
822         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
823                 return "Altered by Implicit ALUA";
824         default:
825                 return "Unknown";
826         }
827
828         return NULL;
829 }
830
831 /*
832  * Used by fabric modules to determine when we need to delay processing
833  * for the Active/NonOptimized paths..
834  */
835 int core_alua_check_nonop_delay(
836         struct se_cmd *cmd)
837 {
838         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
839                 return 0;
840         /*
841          * The ALUA Active/NonOptimized access state delay can be disabled
842          * in via configfs with a value of zero
843          */
844         if (!cmd->alua_nonop_delay)
845                 return 0;
846         /*
847          * struct se_cmd->alua_nonop_delay gets set by a target port group
848          * defined interval in core_alua_state_nonoptimized()
849          */
850         msleep_interruptible(cmd->alua_nonop_delay);
851         return 0;
852 }
853
854 static int core_alua_write_tpg_metadata(
855         const char *path,
856         unsigned char *md_buf,
857         u32 md_buf_len)
858 {
859         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
860         loff_t pos = 0;
861         int ret;
862
863         if (IS_ERR(file)) {
864                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
865                 return -ENODEV;
866         }
867         ret = kernel_write(file, md_buf, md_buf_len, &pos);
868         if (ret < 0)
869                 pr_err("Error writing ALUA metadata file: %s\n", path);
870         fput(file);
871         return (ret < 0) ? -EIO : 0;
872 }
873
874 static int core_alua_update_tpg_primary_metadata(
875         struct t10_alua_tg_pt_gp *tg_pt_gp)
876 {
877         unsigned char *md_buf;
878         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
879         char *path;
880         int len, rc;
881
882         lockdep_assert_held(&tg_pt_gp->tg_pt_gp_transition_mutex);
883
884         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
885         if (!md_buf) {
886                 pr_err("Unable to allocate buf for ALUA metadata\n");
887                 return -ENOMEM;
888         }
889
890         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
891                         "tg_pt_gp_id=%hu\n"
892                         "alua_access_state=0x%02x\n"
893                         "alua_access_status=0x%02x\n",
894                         tg_pt_gp->tg_pt_gp_id,
895                         tg_pt_gp->tg_pt_gp_alua_access_state,
896                         tg_pt_gp->tg_pt_gp_alua_access_status);
897
898         rc = -ENOMEM;
899         path = kasprintf(GFP_KERNEL, "%s/alua/tpgs_%s/%s", db_root,
900                         &wwn->unit_serial[0],
901                         config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
902         if (path) {
903                 rc = core_alua_write_tpg_metadata(path, md_buf, len);
904                 kfree(path);
905         }
906         kfree(md_buf);
907         return rc;
908 }
909
910 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
911 {
912         struct se_dev_entry *se_deve;
913         struct se_lun *lun;
914         struct se_lun_acl *lacl;
915
916         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
917         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
918                                 lun_tg_pt_gp_link) {
919                 /*
920                  * After an implicit target port asymmetric access state
921                  * change, a device server shall establish a unit attention
922                  * condition for the initiator port associated with every I_T
923                  * nexus with the additional sense code set to ASYMMETRIC
924                  * ACCESS STATE CHANGED.
925                  *
926                  * After an explicit target port asymmetric access state
927                  * change, a device server shall establish a unit attention
928                  * condition with the additional sense code set to ASYMMETRIC
929                  * ACCESS STATE CHANGED for the initiator port associated with
930                  * every I_T nexus other than the I_T nexus on which the SET
931                  * TARGET PORT GROUPS command
932                  */
933                 if (!percpu_ref_tryget_live(&lun->lun_ref))
934                         continue;
935                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
936
937                 spin_lock(&lun->lun_deve_lock);
938                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
939                         lacl = se_deve->se_lun_acl;
940
941                         /*
942                          * spc4r37 p.242:
943                          * After an explicit target port asymmetric access
944                          * state change, a device server shall establish a
945                          * unit attention condition with the additional sense
946                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
947                          * the initiator port associated with every I_T nexus
948                          * other than the I_T nexus on which the SET TARGET
949                          * PORT GROUPS command was received.
950                          */
951                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
952                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
953                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
954                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
955                                 continue;
956
957                         /*
958                          * se_deve->se_lun_acl pointer may be NULL for a
959                          * entry created without explicit Node+MappedLUN ACLs
960                          */
961                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
962                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
963                                 continue;
964
965                         core_scsi3_ua_allocate(se_deve, 0x2A,
966                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
967                 }
968                 spin_unlock(&lun->lun_deve_lock);
969
970                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
971                 percpu_ref_put(&lun->lun_ref);
972         }
973         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
974 }
975
976 static int core_alua_do_transition_tg_pt(
977         struct t10_alua_tg_pt_gp *tg_pt_gp,
978         int new_state,
979         int explicit)
980 {
981         int prev_state;
982
983         mutex_lock(&tg_pt_gp->tg_pt_gp_transition_mutex);
984         /* Nothing to be done here */
985         if (tg_pt_gp->tg_pt_gp_alua_access_state == new_state) {
986                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
987                 return 0;
988         }
989
990         if (explicit && new_state == ALUA_ACCESS_STATE_TRANSITION) {
991                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
992                 return -EAGAIN;
993         }
994
995         /*
996          * Save the old primary ALUA access state, and set the current state
997          * to ALUA_ACCESS_STATE_TRANSITION.
998          */
999         prev_state = tg_pt_gp->tg_pt_gp_alua_access_state;
1000         tg_pt_gp->tg_pt_gp_alua_access_state = ALUA_ACCESS_STATE_TRANSITION;
1001         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1002                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1003                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1004
1005         core_alua_queue_state_change_ua(tg_pt_gp);
1006
1007         if (new_state == ALUA_ACCESS_STATE_TRANSITION) {
1008                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1009                 return 0;
1010         }
1011
1012         /*
1013          * Check for the optional ALUA primary state transition delay
1014          */
1015         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1016                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1017
1018         /*
1019          * Set the current primary ALUA access state to the requested new state
1020          */
1021         tg_pt_gp->tg_pt_gp_alua_access_state = new_state;
1022
1023         /*
1024          * Update the ALUA metadata buf that has been allocated in
1025          * core_alua_do_port_transition(), this metadata will be written
1026          * to struct file.
1027          *
1028          * Note that there is the case where we do not want to update the
1029          * metadata when the saved metadata is being parsed in userspace
1030          * when setting the existing port access state and access status.
1031          *
1032          * Also note that the failure to write out the ALUA metadata to
1033          * struct file does NOT affect the actual ALUA transition.
1034          */
1035         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1036                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1037         }
1038
1039         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1040                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1041                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1042                 tg_pt_gp->tg_pt_gp_id,
1043                 core_alua_dump_state(prev_state),
1044                 core_alua_dump_state(new_state));
1045
1046         core_alua_queue_state_change_ua(tg_pt_gp);
1047
1048         mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1049         return 0;
1050 }
1051
1052 int core_alua_do_port_transition(
1053         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1054         struct se_device *l_dev,
1055         struct se_lun *l_lun,
1056         struct se_node_acl *l_nacl,
1057         int new_state,
1058         int explicit)
1059 {
1060         struct se_device *dev;
1061         struct t10_alua_lu_gp *lu_gp;
1062         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1063         struct t10_alua_tg_pt_gp *tg_pt_gp;
1064         int primary, valid_states, rc = 0;
1065
1066         if (l_dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
1067                 return -ENODEV;
1068
1069         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1070         if (core_alua_check_transition(new_state, valid_states, &primary,
1071                                        explicit) != 0)
1072                 return -EINVAL;
1073
1074         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1075         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1076         lu_gp = local_lu_gp_mem->lu_gp;
1077         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1078         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1079         /*
1080          * For storage objects that are members of the 'default_lu_gp',
1081          * we only do transition on the passed *l_tp_pt_gp, and not
1082          * on all of the matching target port groups IDs in default_lu_gp.
1083          */
1084         if (!lu_gp->lu_gp_id) {
1085                 /*
1086                  * core_alua_do_transition_tg_pt() will always return
1087                  * success.
1088                  */
1089                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1090                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1091                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1092                                                    new_state, explicit);
1093                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1094                 return rc;
1095         }
1096         /*
1097          * For all other LU groups aside from 'default_lu_gp', walk all of
1098          * the associated storage objects looking for a matching target port
1099          * group ID from the local target port group.
1100          */
1101         spin_lock(&lu_gp->lu_gp_lock);
1102         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1103                                 lu_gp_mem_list) {
1104
1105                 dev = lu_gp_mem->lu_gp_mem_dev;
1106                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1107                 spin_unlock(&lu_gp->lu_gp_lock);
1108
1109                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1110                 list_for_each_entry(tg_pt_gp,
1111                                 &dev->t10_alua.tg_pt_gps_list,
1112                                 tg_pt_gp_list) {
1113
1114                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1115                                 continue;
1116                         /*
1117                          * If the target behavior port asymmetric access state
1118                          * is changed for any target port group accessible via
1119                          * a logical unit within a LU group, the target port
1120                          * behavior group asymmetric access states for the same
1121                          * target port group accessible via other logical units
1122                          * in that LU group will also change.
1123                          */
1124                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1125                                 continue;
1126
1127                         if (l_tg_pt_gp == tg_pt_gp) {
1128                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1129                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1130                         } else {
1131                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1132                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1133                         }
1134                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1135                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1136                         /*
1137                          * core_alua_do_transition_tg_pt() will always return
1138                          * success.
1139                          */
1140                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1141                                         new_state, explicit);
1142
1143                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1144                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1145                         if (rc)
1146                                 break;
1147                 }
1148                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1149
1150                 spin_lock(&lu_gp->lu_gp_lock);
1151                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1152         }
1153         spin_unlock(&lu_gp->lu_gp_lock);
1154
1155         if (!rc) {
1156                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1157                          " Group IDs: %hu %s transition to primary state: %s\n",
1158                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1159                          l_tg_pt_gp->tg_pt_gp_id,
1160                          (explicit) ? "explicit" : "implicit",
1161                          core_alua_dump_state(new_state));
1162         }
1163
1164         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1165         return rc;
1166 }
1167
1168 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1169 {
1170         struct se_portal_group *se_tpg = lun->lun_tpg;
1171         unsigned char *md_buf;
1172         char *path;
1173         int len, rc;
1174
1175         mutex_lock(&lun->lun_tg_pt_md_mutex);
1176
1177         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1178         if (!md_buf) {
1179                 pr_err("Unable to allocate buf for ALUA metadata\n");
1180                 rc = -ENOMEM;
1181                 goto out_unlock;
1182         }
1183
1184         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1185                         "alua_tg_pt_status=0x%02x\n",
1186                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1187                         lun->lun_tg_pt_secondary_stat);
1188
1189         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) {
1190                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s+%hu/lun_%llu",
1191                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1192                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1193                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
1194                                 lun->unpacked_lun);
1195         } else {
1196                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s/lun_%llu",
1197                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1198                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1199                                 lun->unpacked_lun);
1200         }
1201         if (!path) {
1202                 rc = -ENOMEM;
1203                 goto out_free;
1204         }
1205
1206         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1207         kfree(path);
1208 out_free:
1209         kfree(md_buf);
1210 out_unlock:
1211         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1212         return rc;
1213 }
1214
1215 static int core_alua_set_tg_pt_secondary_state(
1216         struct se_lun *lun,
1217         int explicit,
1218         int offline)
1219 {
1220         struct t10_alua_tg_pt_gp *tg_pt_gp;
1221         int trans_delay_msecs;
1222
1223         rcu_read_lock();
1224         tg_pt_gp = rcu_dereference(lun->lun_tg_pt_gp);
1225         if (!tg_pt_gp) {
1226                 rcu_read_unlock();
1227                 pr_err("Unable to complete secondary state"
1228                                 " transition\n");
1229                 return -EINVAL;
1230         }
1231         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1232         /*
1233          * Set the secondary ALUA target port access state to OFFLINE
1234          * or release the previously secondary state for struct se_lun
1235          */
1236         if (offline)
1237                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1238         else
1239                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1240
1241         lun->lun_tg_pt_secondary_stat = (explicit) ?
1242                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1243                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1244
1245         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1246                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1247                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1248                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1249
1250         rcu_read_unlock();
1251         /*
1252          * Do the optional transition delay after we set the secondary
1253          * ALUA access state.
1254          */
1255         if (trans_delay_msecs != 0)
1256                 msleep_interruptible(trans_delay_msecs);
1257         /*
1258          * See if we need to update the ALUA fabric port metadata for
1259          * secondary state and status
1260          */
1261         if (lun->lun_tg_pt_secondary_write_md)
1262                 core_alua_update_tpg_secondary_metadata(lun);
1263
1264         return 0;
1265 }
1266
1267 struct t10_alua_lba_map *
1268 core_alua_allocate_lba_map(struct list_head *list,
1269                            u64 first_lba, u64 last_lba)
1270 {
1271         struct t10_alua_lba_map *lba_map;
1272
1273         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1274         if (!lba_map) {
1275                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1276                 return ERR_PTR(-ENOMEM);
1277         }
1278         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1279         lba_map->lba_map_first_lba = first_lba;
1280         lba_map->lba_map_last_lba = last_lba;
1281
1282         list_add_tail(&lba_map->lba_map_list, list);
1283         return lba_map;
1284 }
1285
1286 int
1287 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1288                                int pg_id, int state)
1289 {
1290         struct t10_alua_lba_map_member *lba_map_mem;
1291
1292         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1293                             lba_map_mem_list) {
1294                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1295                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1296                         return -EINVAL;
1297                 }
1298         }
1299
1300         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1301         if (!lba_map_mem) {
1302                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1303                 return -ENOMEM;
1304         }
1305         lba_map_mem->lba_map_mem_alua_state = state;
1306         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1307
1308         list_add_tail(&lba_map_mem->lba_map_mem_list,
1309                       &lba_map->lba_map_mem_list);
1310         return 0;
1311 }
1312
1313 void
1314 core_alua_free_lba_map(struct list_head *lba_list)
1315 {
1316         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1317         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1318
1319         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1320                                  lba_map_list) {
1321                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1322                                          &lba_map->lba_map_mem_list,
1323                                          lba_map_mem_list) {
1324                         list_del(&lba_map_mem->lba_map_mem_list);
1325                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1326                                         lba_map_mem);
1327                 }
1328                 list_del(&lba_map->lba_map_list);
1329                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1330         }
1331 }
1332
1333 void
1334 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1335                       int segment_size, int segment_mult)
1336 {
1337         struct list_head old_lba_map_list;
1338         struct t10_alua_tg_pt_gp *tg_pt_gp;
1339         int activate = 0, supported;
1340
1341         INIT_LIST_HEAD(&old_lba_map_list);
1342         spin_lock(&dev->t10_alua.lba_map_lock);
1343         dev->t10_alua.lba_map_segment_size = segment_size;
1344         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1345         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1346         if (lba_map_list) {
1347                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1348                 activate = 1;
1349         }
1350         spin_unlock(&dev->t10_alua.lba_map_lock);
1351         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1352         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1353                             tg_pt_gp_list) {
1354
1355                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1356                         continue;
1357                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1358                 if (activate)
1359                         supported |= ALUA_LBD_SUP;
1360                 else
1361                         supported &= ~ALUA_LBD_SUP;
1362                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1363         }
1364         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1365         core_alua_free_lba_map(&old_lba_map_list);
1366 }
1367
1368 struct t10_alua_lu_gp *
1369 core_alua_allocate_lu_gp(const char *name, int def_group)
1370 {
1371         struct t10_alua_lu_gp *lu_gp;
1372
1373         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1374         if (!lu_gp) {
1375                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1376                 return ERR_PTR(-ENOMEM);
1377         }
1378         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1379         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1380         spin_lock_init(&lu_gp->lu_gp_lock);
1381         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1382
1383         if (def_group) {
1384                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1385                 lu_gp->lu_gp_valid_id = 1;
1386                 alua_lu_gps_count++;
1387         }
1388
1389         return lu_gp;
1390 }
1391
1392 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1393 {
1394         struct t10_alua_lu_gp *lu_gp_tmp;
1395         u16 lu_gp_id_tmp;
1396         /*
1397          * The lu_gp->lu_gp_id may only be set once..
1398          */
1399         if (lu_gp->lu_gp_valid_id) {
1400                 pr_warn("ALUA LU Group already has a valid ID,"
1401                         " ignoring request\n");
1402                 return -EINVAL;
1403         }
1404
1405         spin_lock(&lu_gps_lock);
1406         if (alua_lu_gps_count == 0x0000ffff) {
1407                 pr_err("Maximum ALUA alua_lu_gps_count:"
1408                                 " 0x0000ffff reached\n");
1409                 spin_unlock(&lu_gps_lock);
1410                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1411                 return -ENOSPC;
1412         }
1413 again:
1414         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1415                                 alua_lu_gps_counter++;
1416
1417         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1418                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1419                         if (!lu_gp_id)
1420                                 goto again;
1421
1422                         pr_warn("ALUA Logical Unit Group ID: %hu"
1423                                 " already exists, ignoring request\n",
1424                                 lu_gp_id);
1425                         spin_unlock(&lu_gps_lock);
1426                         return -EINVAL;
1427                 }
1428         }
1429
1430         lu_gp->lu_gp_id = lu_gp_id_tmp;
1431         lu_gp->lu_gp_valid_id = 1;
1432         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1433         alua_lu_gps_count++;
1434         spin_unlock(&lu_gps_lock);
1435
1436         return 0;
1437 }
1438
1439 static struct t10_alua_lu_gp_member *
1440 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1441 {
1442         struct t10_alua_lu_gp_member *lu_gp_mem;
1443
1444         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1445         if (!lu_gp_mem) {
1446                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1447                 return ERR_PTR(-ENOMEM);
1448         }
1449         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1450         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1451         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1452
1453         lu_gp_mem->lu_gp_mem_dev = dev;
1454         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1455
1456         return lu_gp_mem;
1457 }
1458
1459 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1460 {
1461         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1462         /*
1463          * Once we have reached this point, config_item_put() has
1464          * already been called from target_core_alua_drop_lu_gp().
1465          *
1466          * Here, we remove the *lu_gp from the global list so that
1467          * no associations can be made while we are releasing
1468          * struct t10_alua_lu_gp.
1469          */
1470         spin_lock(&lu_gps_lock);
1471         list_del(&lu_gp->lu_gp_node);
1472         alua_lu_gps_count--;
1473         spin_unlock(&lu_gps_lock);
1474         /*
1475          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1476          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1477          * released with core_alua_put_lu_gp_from_name()
1478          */
1479         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1480                 cpu_relax();
1481         /*
1482          * Release reference to struct t10_alua_lu_gp * from all associated
1483          * struct se_device.
1484          */
1485         spin_lock(&lu_gp->lu_gp_lock);
1486         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1487                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1488                 if (lu_gp_mem->lu_gp_assoc) {
1489                         list_del(&lu_gp_mem->lu_gp_mem_list);
1490                         lu_gp->lu_gp_members--;
1491                         lu_gp_mem->lu_gp_assoc = 0;
1492                 }
1493                 spin_unlock(&lu_gp->lu_gp_lock);
1494                 /*
1495                  *
1496                  * lu_gp_mem is associated with a single
1497                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1498                  * struct se_device is released via core_alua_free_lu_gp_mem().
1499                  *
1500                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1501                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1502                  */
1503                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1504                 if (lu_gp != default_lu_gp)
1505                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1506                                         default_lu_gp);
1507                 else
1508                         lu_gp_mem->lu_gp = NULL;
1509                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1510
1511                 spin_lock(&lu_gp->lu_gp_lock);
1512         }
1513         spin_unlock(&lu_gp->lu_gp_lock);
1514
1515         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1516 }
1517
1518 void core_alua_free_lu_gp_mem(struct se_device *dev)
1519 {
1520         struct t10_alua_lu_gp *lu_gp;
1521         struct t10_alua_lu_gp_member *lu_gp_mem;
1522
1523         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1524         if (!lu_gp_mem)
1525                 return;
1526
1527         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1528                 cpu_relax();
1529
1530         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1531         lu_gp = lu_gp_mem->lu_gp;
1532         if (lu_gp) {
1533                 spin_lock(&lu_gp->lu_gp_lock);
1534                 if (lu_gp_mem->lu_gp_assoc) {
1535                         list_del(&lu_gp_mem->lu_gp_mem_list);
1536                         lu_gp->lu_gp_members--;
1537                         lu_gp_mem->lu_gp_assoc = 0;
1538                 }
1539                 spin_unlock(&lu_gp->lu_gp_lock);
1540                 lu_gp_mem->lu_gp = NULL;
1541         }
1542         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1543
1544         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1545 }
1546
1547 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1548 {
1549         struct t10_alua_lu_gp *lu_gp;
1550         struct config_item *ci;
1551
1552         spin_lock(&lu_gps_lock);
1553         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1554                 if (!lu_gp->lu_gp_valid_id)
1555                         continue;
1556                 ci = &lu_gp->lu_gp_group.cg_item;
1557                 if (!strcmp(config_item_name(ci), name)) {
1558                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1559                         spin_unlock(&lu_gps_lock);
1560                         return lu_gp;
1561                 }
1562         }
1563         spin_unlock(&lu_gps_lock);
1564
1565         return NULL;
1566 }
1567
1568 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1569 {
1570         spin_lock(&lu_gps_lock);
1571         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1572         spin_unlock(&lu_gps_lock);
1573 }
1574
1575 /*
1576  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1577  */
1578 void __core_alua_attach_lu_gp_mem(
1579         struct t10_alua_lu_gp_member *lu_gp_mem,
1580         struct t10_alua_lu_gp *lu_gp)
1581 {
1582         spin_lock(&lu_gp->lu_gp_lock);
1583         lu_gp_mem->lu_gp = lu_gp;
1584         lu_gp_mem->lu_gp_assoc = 1;
1585         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1586         lu_gp->lu_gp_members++;
1587         spin_unlock(&lu_gp->lu_gp_lock);
1588 }
1589
1590 /*
1591  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1592  */
1593 void __core_alua_drop_lu_gp_mem(
1594         struct t10_alua_lu_gp_member *lu_gp_mem,
1595         struct t10_alua_lu_gp *lu_gp)
1596 {
1597         spin_lock(&lu_gp->lu_gp_lock);
1598         list_del(&lu_gp_mem->lu_gp_mem_list);
1599         lu_gp_mem->lu_gp = NULL;
1600         lu_gp_mem->lu_gp_assoc = 0;
1601         lu_gp->lu_gp_members--;
1602         spin_unlock(&lu_gp->lu_gp_lock);
1603 }
1604
1605 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1606                 const char *name, int def_group)
1607 {
1608         struct t10_alua_tg_pt_gp *tg_pt_gp;
1609
1610         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1611         if (!tg_pt_gp) {
1612                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1613                 return NULL;
1614         }
1615         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1616         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1617         mutex_init(&tg_pt_gp->tg_pt_gp_transition_mutex);
1618         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1619         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1620         tg_pt_gp->tg_pt_gp_dev = dev;
1621         tg_pt_gp->tg_pt_gp_alua_access_state =
1622                         ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED;
1623         /*
1624          * Enable both explicit and implicit ALUA support by default
1625          */
1626         tg_pt_gp->tg_pt_gp_alua_access_type =
1627                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1628         /*
1629          * Set the default Active/NonOptimized Delay in milliseconds
1630          */
1631         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1632         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1633         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1634
1635         /*
1636          * Enable all supported states
1637          */
1638         tg_pt_gp->tg_pt_gp_alua_supported_states =
1639             ALUA_T_SUP | ALUA_O_SUP |
1640             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1641
1642         if (def_group) {
1643                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1644                 tg_pt_gp->tg_pt_gp_id =
1645                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1646                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1647                 dev->t10_alua.alua_tg_pt_gps_count++;
1648                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1649                               &dev->t10_alua.tg_pt_gps_list);
1650                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1651         }
1652
1653         return tg_pt_gp;
1654 }
1655
1656 int core_alua_set_tg_pt_gp_id(
1657         struct t10_alua_tg_pt_gp *tg_pt_gp,
1658         u16 tg_pt_gp_id)
1659 {
1660         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1661         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1662         u16 tg_pt_gp_id_tmp;
1663
1664         /*
1665          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1666          */
1667         if (tg_pt_gp->tg_pt_gp_valid_id) {
1668                 pr_warn("ALUA TG PT Group already has a valid ID,"
1669                         " ignoring request\n");
1670                 return -EINVAL;
1671         }
1672
1673         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1674         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1675                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1676                         " 0x0000ffff reached\n");
1677                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1678                 return -ENOSPC;
1679         }
1680 again:
1681         tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1682                         dev->t10_alua.alua_tg_pt_gps_counter++;
1683
1684         list_for_each_entry(tg_pt_gp_tmp, &dev->t10_alua.tg_pt_gps_list,
1685                         tg_pt_gp_list) {
1686                 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1687                         if (!tg_pt_gp_id)
1688                                 goto again;
1689
1690                         pr_err("ALUA Target Port Group ID: %hu already"
1691                                 " exists, ignoring request\n", tg_pt_gp_id);
1692                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1693                         return -EINVAL;
1694                 }
1695         }
1696
1697         tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1698         tg_pt_gp->tg_pt_gp_valid_id = 1;
1699         list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1700                         &dev->t10_alua.tg_pt_gps_list);
1701         dev->t10_alua.alua_tg_pt_gps_count++;
1702         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1703
1704         return 0;
1705 }
1706
1707 void core_alua_free_tg_pt_gp(
1708         struct t10_alua_tg_pt_gp *tg_pt_gp)
1709 {
1710         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1711         struct se_lun *lun, *next;
1712
1713         /*
1714          * Once we have reached this point, config_item_put() has already
1715          * been called from target_core_alua_drop_tg_pt_gp().
1716          *
1717          * Here we remove *tg_pt_gp from the global list so that
1718          * no associations *OR* explicit ALUA via SET_TARGET_PORT_GROUPS
1719          * can be made while we are releasing struct t10_alua_tg_pt_gp.
1720          */
1721         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1722         if (tg_pt_gp->tg_pt_gp_valid_id) {
1723                 list_del(&tg_pt_gp->tg_pt_gp_list);
1724                 dev->t10_alua.alua_tg_pt_gps_count--;
1725         }
1726         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1727
1728         /*
1729          * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1730          * core_alua_get_tg_pt_gp_by_name() in
1731          * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1732          * to be released with core_alua_put_tg_pt_gp_from_name().
1733          */
1734         while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1735                 cpu_relax();
1736
1737         /*
1738          * Release reference to struct t10_alua_tg_pt_gp from all associated
1739          * struct se_port.
1740          */
1741         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1742         list_for_each_entry_safe(lun, next,
1743                         &tg_pt_gp->tg_pt_gp_lun_list, lun_tg_pt_gp_link) {
1744                 list_del_init(&lun->lun_tg_pt_gp_link);
1745                 tg_pt_gp->tg_pt_gp_members--;
1746
1747                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1748                 /*
1749                  * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1750                  * assume we want to re-associate a given tg_pt_gp_mem with
1751                  * default_tg_pt_gp.
1752                  */
1753                 spin_lock(&lun->lun_tg_pt_gp_lock);
1754                 if (tg_pt_gp != dev->t10_alua.default_tg_pt_gp) {
1755                         __target_attach_tg_pt_gp(lun,
1756                                         dev->t10_alua.default_tg_pt_gp);
1757                 } else
1758                         rcu_assign_pointer(lun->lun_tg_pt_gp, NULL);
1759                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1760
1761                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1762         }
1763         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1764
1765         synchronize_rcu();
1766         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1767 }
1768
1769 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1770                 struct se_device *dev, const char *name)
1771 {
1772         struct t10_alua_tg_pt_gp *tg_pt_gp;
1773         struct config_item *ci;
1774
1775         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1776         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1777                         tg_pt_gp_list) {
1778                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1779                         continue;
1780                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1781                 if (!strcmp(config_item_name(ci), name)) {
1782                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1783                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1784                         return tg_pt_gp;
1785                 }
1786         }
1787         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1788
1789         return NULL;
1790 }
1791
1792 static void core_alua_put_tg_pt_gp_from_name(
1793         struct t10_alua_tg_pt_gp *tg_pt_gp)
1794 {
1795         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1796
1797         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1798         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1799         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1800 }
1801
1802 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1803                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1804 {
1805         struct se_dev_entry *se_deve;
1806
1807         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1808
1809         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1810         rcu_assign_pointer(lun->lun_tg_pt_gp, tg_pt_gp);
1811         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1812         tg_pt_gp->tg_pt_gp_members++;
1813         spin_lock(&lun->lun_deve_lock);
1814         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1815                 core_scsi3_ua_allocate(se_deve, 0x3f,
1816                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1817         spin_unlock(&lun->lun_deve_lock);
1818         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1819 }
1820
1821 void target_attach_tg_pt_gp(struct se_lun *lun,
1822                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1823 {
1824         spin_lock(&lun->lun_tg_pt_gp_lock);
1825         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1826         spin_unlock(&lun->lun_tg_pt_gp_lock);
1827         synchronize_rcu();
1828 }
1829
1830 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1831                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1832 {
1833         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1834
1835         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1836         list_del_init(&lun->lun_tg_pt_gp_link);
1837         tg_pt_gp->tg_pt_gp_members--;
1838         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1839 }
1840
1841 void target_detach_tg_pt_gp(struct se_lun *lun)
1842 {
1843         struct t10_alua_tg_pt_gp *tg_pt_gp;
1844
1845         spin_lock(&lun->lun_tg_pt_gp_lock);
1846         tg_pt_gp = rcu_dereference_check(lun->lun_tg_pt_gp,
1847                                 lockdep_is_held(&lun->lun_tg_pt_gp_lock));
1848         if (tg_pt_gp) {
1849                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1850                 rcu_assign_pointer(lun->lun_tg_pt_gp, NULL);
1851         }
1852         spin_unlock(&lun->lun_tg_pt_gp_lock);
1853         synchronize_rcu();
1854 }
1855
1856 static void target_swap_tg_pt_gp(struct se_lun *lun,
1857                                  struct t10_alua_tg_pt_gp *old_tg_pt_gp,
1858                                  struct t10_alua_tg_pt_gp *new_tg_pt_gp)
1859 {
1860         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1861
1862         if (old_tg_pt_gp)
1863                 __target_detach_tg_pt_gp(lun, old_tg_pt_gp);
1864         __target_attach_tg_pt_gp(lun, new_tg_pt_gp);
1865 }
1866
1867 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1868 {
1869         struct config_item *tg_pt_ci;
1870         struct t10_alua_tg_pt_gp *tg_pt_gp;
1871         ssize_t len = 0;
1872
1873         rcu_read_lock();
1874         tg_pt_gp = rcu_dereference(lun->lun_tg_pt_gp);
1875         if (tg_pt_gp) {
1876                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1877                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1878                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1879                         "Primary Access Status: %s\nTG Port Secondary Access"
1880                         " State: %s\nTG Port Secondary Access Status: %s\n",
1881                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1882                         core_alua_dump_state(
1883                                 tg_pt_gp->tg_pt_gp_alua_access_state),
1884                         core_alua_dump_status(
1885                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1886                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1887                         "Offline" : "None",
1888                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1889         }
1890         rcu_read_unlock();
1891
1892         return len;
1893 }
1894
1895 ssize_t core_alua_store_tg_pt_gp_info(
1896         struct se_lun *lun,
1897         const char *page,
1898         size_t count)
1899 {
1900         struct se_portal_group *tpg = lun->lun_tpg;
1901         /*
1902          * rcu_dereference_raw protected by se_lun->lun_group symlink
1903          * reference to se_device->dev_group.
1904          */
1905         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1906         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1907         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1908         int move = 0;
1909
1910         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1911             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1912                 return -ENODEV;
1913
1914         if (count > TG_PT_GROUP_NAME_BUF) {
1915                 pr_err("ALUA Target Port Group alias too large!\n");
1916                 return -EINVAL;
1917         }
1918         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1919         memcpy(buf, page, count);
1920         /*
1921          * Any ALUA target port group alias besides "NULL" means we will be
1922          * making a new group association.
1923          */
1924         if (strcmp(strstrip(buf), "NULL")) {
1925                 /*
1926                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1927                  * struct t10_alua_tg_pt_gp.  This reference is released with
1928                  * core_alua_put_tg_pt_gp_from_name() below.
1929                  */
1930                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1931                                         strstrip(buf));
1932                 if (!tg_pt_gp_new)
1933                         return -ENODEV;
1934         }
1935
1936         spin_lock(&lun->lun_tg_pt_gp_lock);
1937         tg_pt_gp = rcu_dereference_check(lun->lun_tg_pt_gp,
1938                                 lockdep_is_held(&lun->lun_tg_pt_gp_lock));
1939         if (tg_pt_gp) {
1940                 /*
1941                  * Clearing an existing tg_pt_gp association, and replacing
1942                  * with the default_tg_pt_gp.
1943                  */
1944                 if (!tg_pt_gp_new) {
1945                         pr_debug("Target_Core_ConfigFS: Moving"
1946                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1947                                 " alua/%s, ID: %hu back to"
1948                                 " default_tg_pt_gp\n",
1949                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1950                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1951                                 config_item_name(&lun->lun_group.cg_item),
1952                                 config_item_name(
1953                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1954                                 tg_pt_gp->tg_pt_gp_id);
1955
1956                         target_swap_tg_pt_gp(lun, tg_pt_gp,
1957                                         dev->t10_alua.default_tg_pt_gp);
1958                         spin_unlock(&lun->lun_tg_pt_gp_lock);
1959
1960                         goto sync_rcu;
1961                 }
1962                 move = 1;
1963         }
1964
1965         target_swap_tg_pt_gp(lun, tg_pt_gp, tg_pt_gp_new);
1966         spin_unlock(&lun->lun_tg_pt_gp_lock);
1967         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1968                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1969                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1970                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1971                 config_item_name(&lun->lun_group.cg_item),
1972                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1973                 tg_pt_gp_new->tg_pt_gp_id);
1974
1975         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1976 sync_rcu:
1977         synchronize_rcu();
1978         return count;
1979 }
1980
1981 ssize_t core_alua_show_access_type(
1982         struct t10_alua_tg_pt_gp *tg_pt_gp,
1983         char *page)
1984 {
1985         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
1986             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
1987                 return sprintf(page, "Implicit and Explicit\n");
1988         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
1989                 return sprintf(page, "Implicit\n");
1990         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
1991                 return sprintf(page, "Explicit\n");
1992         else
1993                 return sprintf(page, "None\n");
1994 }
1995
1996 ssize_t core_alua_store_access_type(
1997         struct t10_alua_tg_pt_gp *tg_pt_gp,
1998         const char *page,
1999         size_t count)
2000 {
2001         unsigned long tmp;
2002         int ret;
2003
2004         ret = kstrtoul(page, 0, &tmp);
2005         if (ret < 0) {
2006                 pr_err("Unable to extract alua_access_type\n");
2007                 return ret;
2008         }
2009         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
2010                 pr_err("Illegal value for alua_access_type:"
2011                                 " %lu\n", tmp);
2012                 return -EINVAL;
2013         }
2014         if (tmp == 3)
2015                 tg_pt_gp->tg_pt_gp_alua_access_type =
2016                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2017         else if (tmp == 2)
2018                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2019         else if (tmp == 1)
2020                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2021         else
2022                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2023
2024         return count;
2025 }
2026
2027 ssize_t core_alua_show_nonop_delay_msecs(
2028         struct t10_alua_tg_pt_gp *tg_pt_gp,
2029         char *page)
2030 {
2031         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2032 }
2033
2034 ssize_t core_alua_store_nonop_delay_msecs(
2035         struct t10_alua_tg_pt_gp *tg_pt_gp,
2036         const char *page,
2037         size_t count)
2038 {
2039         unsigned long tmp;
2040         int ret;
2041
2042         ret = kstrtoul(page, 0, &tmp);
2043         if (ret < 0) {
2044                 pr_err("Unable to extract nonop_delay_msecs\n");
2045                 return ret;
2046         }
2047         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2048                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2049                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2050                         ALUA_MAX_NONOP_DELAY_MSECS);
2051                 return -EINVAL;
2052         }
2053         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2054
2055         return count;
2056 }
2057
2058 ssize_t core_alua_show_trans_delay_msecs(
2059         struct t10_alua_tg_pt_gp *tg_pt_gp,
2060         char *page)
2061 {
2062         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2063 }
2064
2065 ssize_t core_alua_store_trans_delay_msecs(
2066         struct t10_alua_tg_pt_gp *tg_pt_gp,
2067         const char *page,
2068         size_t count)
2069 {
2070         unsigned long tmp;
2071         int ret;
2072
2073         ret = kstrtoul(page, 0, &tmp);
2074         if (ret < 0) {
2075                 pr_err("Unable to extract trans_delay_msecs\n");
2076                 return ret;
2077         }
2078         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2079                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2080                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2081                         ALUA_MAX_TRANS_DELAY_MSECS);
2082                 return -EINVAL;
2083         }
2084         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2085
2086         return count;
2087 }
2088
2089 ssize_t core_alua_show_implicit_trans_secs(
2090         struct t10_alua_tg_pt_gp *tg_pt_gp,
2091         char *page)
2092 {
2093         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2094 }
2095
2096 ssize_t core_alua_store_implicit_trans_secs(
2097         struct t10_alua_tg_pt_gp *tg_pt_gp,
2098         const char *page,
2099         size_t count)
2100 {
2101         unsigned long tmp;
2102         int ret;
2103
2104         ret = kstrtoul(page, 0, &tmp);
2105         if (ret < 0) {
2106                 pr_err("Unable to extract implicit_trans_secs\n");
2107                 return ret;
2108         }
2109         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2110                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2111                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2112                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2113                 return  -EINVAL;
2114         }
2115         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2116
2117         return count;
2118 }
2119
2120 ssize_t core_alua_show_preferred_bit(
2121         struct t10_alua_tg_pt_gp *tg_pt_gp,
2122         char *page)
2123 {
2124         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2125 }
2126
2127 ssize_t core_alua_store_preferred_bit(
2128         struct t10_alua_tg_pt_gp *tg_pt_gp,
2129         const char *page,
2130         size_t count)
2131 {
2132         unsigned long tmp;
2133         int ret;
2134
2135         ret = kstrtoul(page, 0, &tmp);
2136         if (ret < 0) {
2137                 pr_err("Unable to extract preferred ALUA value\n");
2138                 return ret;
2139         }
2140         if ((tmp != 0) && (tmp != 1)) {
2141                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2142                 return -EINVAL;
2143         }
2144         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2145
2146         return count;
2147 }
2148
2149 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2150 {
2151         return sprintf(page, "%d\n",
2152                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2153 }
2154
2155 ssize_t core_alua_store_offline_bit(
2156         struct se_lun *lun,
2157         const char *page,
2158         size_t count)
2159 {
2160         /*
2161          * rcu_dereference_raw protected by se_lun->lun_group symlink
2162          * reference to se_device->dev_group.
2163          */
2164         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2165         unsigned long tmp;
2166         int ret;
2167
2168         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2169             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2170                 return -ENODEV;
2171
2172         ret = kstrtoul(page, 0, &tmp);
2173         if (ret < 0) {
2174                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2175                 return ret;
2176         }
2177         if ((tmp != 0) && (tmp != 1)) {
2178                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2179                                 tmp);
2180                 return -EINVAL;
2181         }
2182
2183         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2184         if (ret < 0)
2185                 return -EINVAL;
2186
2187         return count;
2188 }
2189
2190 ssize_t core_alua_show_secondary_status(
2191         struct se_lun *lun,
2192         char *page)
2193 {
2194         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2195 }
2196
2197 ssize_t core_alua_store_secondary_status(
2198         struct se_lun *lun,
2199         const char *page,
2200         size_t count)
2201 {
2202         unsigned long tmp;
2203         int ret;
2204
2205         ret = kstrtoul(page, 0, &tmp);
2206         if (ret < 0) {
2207                 pr_err("Unable to extract alua_tg_pt_status\n");
2208                 return ret;
2209         }
2210         if ((tmp != ALUA_STATUS_NONE) &&
2211             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2212             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2213                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2214                                 tmp);
2215                 return -EINVAL;
2216         }
2217         lun->lun_tg_pt_secondary_stat = (int)tmp;
2218
2219         return count;
2220 }
2221
2222 ssize_t core_alua_show_secondary_write_metadata(
2223         struct se_lun *lun,
2224         char *page)
2225 {
2226         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2227 }
2228
2229 ssize_t core_alua_store_secondary_write_metadata(
2230         struct se_lun *lun,
2231         const char *page,
2232         size_t count)
2233 {
2234         unsigned long tmp;
2235         int ret;
2236
2237         ret = kstrtoul(page, 0, &tmp);
2238         if (ret < 0) {
2239                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2240                 return ret;
2241         }
2242         if ((tmp != 0) && (tmp != 1)) {
2243                 pr_err("Illegal value for alua_tg_pt_write_md:"
2244                                 " %lu\n", tmp);
2245                 return -EINVAL;
2246         }
2247         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2248
2249         return count;
2250 }
2251
2252 int core_setup_alua(struct se_device *dev)
2253 {
2254         if (!(dev->transport_flags &
2255              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2256             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2257                 struct t10_alua_lu_gp_member *lu_gp_mem;
2258
2259                 /*
2260                  * Associate this struct se_device with the default ALUA
2261                  * LUN Group.
2262                  */
2263                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2264                 if (IS_ERR(lu_gp_mem))
2265                         return PTR_ERR(lu_gp_mem);
2266
2267                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2268                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2269                                 default_lu_gp);
2270                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2271
2272                 pr_debug("%s: Adding to default ALUA LU Group:"
2273                         " core/alua/lu_gps/default_lu_gp\n",
2274                         dev->transport->name);
2275         }
2276
2277         return 0;
2278 }