Merge tag 'mtd/for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux
[linux-2.6-microblaze.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                 /*
168                  * Check if the Target port group and Target port descriptor list
169                  * based on tg_pt_gp_members count will fit into the response payload.
170                  * Otherwise, bump rd_len to let the initiator know we have exceeded
171                  * the allocation length and the response is truncated.
172                  */
173                 if ((off + 8 + (tg_pt_gp->tg_pt_gp_members * 4)) >
174                      cmd->data_length) {
175                         rd_len += 8 + (tg_pt_gp->tg_pt_gp_members * 4);
176                         continue;
177                 }
178                 /*
179                  * PREF: Preferred target port bit, determine if this
180                  * bit should be set for port group.
181                  */
182                 if (tg_pt_gp->tg_pt_gp_pref)
183                         buf[off] = 0x80;
184                 /*
185                  * Set the ASYMMETRIC ACCESS State
186                  */
187                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_access_state & 0xff;
188                 /*
189                  * Set supported ASYMMETRIC ACCESS State bits
190                  */
191                 buf[off++] |= tg_pt_gp->tg_pt_gp_alua_supported_states;
192                 /*
193                  * TARGET PORT GROUP
194                  */
195                 put_unaligned_be16(tg_pt_gp->tg_pt_gp_id, &buf[off]);
196                 off += 2;
197
198                 off++; /* Skip over Reserved */
199                 /*
200                  * STATUS CODE
201                  */
202                 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
203                 /*
204                  * Vendor Specific field
205                  */
206                 buf[off++] = 0x00;
207                 /*
208                  * TARGET PORT COUNT
209                  */
210                 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
211                 rd_len += 8;
212
213                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
214                 list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
215                                 lun_tg_pt_gp_link) {
216                         /*
217                          * Start Target Port descriptor format
218                          *
219                          * See spc4r17 section 6.2.7 Table 247
220                          */
221                         off += 2; /* Skip over Obsolete */
222                         /*
223                          * Set RELATIVE TARGET PORT IDENTIFIER
224                          */
225                         put_unaligned_be16(lun->lun_rtpi, &buf[off]);
226                         off += 2;
227                         rd_len += 4;
228                 }
229                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
230         }
231         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
232         /*
233          * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
234          */
235         put_unaligned_be32(rd_len, &buf[0]);
236
237         /*
238          * Fill in the Extended header parameter data format if requested
239          */
240         if (ext_hdr != 0) {
241                 buf[4] = 0x10;
242                 /*
243                  * Set the implicit transition time (in seconds) for the application
244                  * client to use as a base for it's transition timeout value.
245                  *
246                  * Use the current tg_pt_gp_mem -> tg_pt_gp membership from the LUN
247                  * this CDB was received upon to determine this value individually
248                  * for ALUA target port group.
249                  */
250                 spin_lock(&cmd->se_lun->lun_tg_pt_gp_lock);
251                 tg_pt_gp = cmd->se_lun->lun_tg_pt_gp;
252                 if (tg_pt_gp)
253                         buf[5] = tg_pt_gp->tg_pt_gp_implicit_trans_secs;
254                 spin_unlock(&cmd->se_lun->lun_tg_pt_gp_lock);
255         }
256         transport_kunmap_data_sg(cmd);
257
258         target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, rd_len + 4);
259         return 0;
260 }
261
262 /*
263  * SET_TARGET_PORT_GROUPS for explicit ALUA operation.
264  *
265  * See spc4r17 section 6.35
266  */
267 sense_reason_t
268 target_emulate_set_target_port_groups(struct se_cmd *cmd)
269 {
270         struct se_device *dev = cmd->se_dev;
271         struct se_lun *l_lun = cmd->se_lun;
272         struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
273         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
274         unsigned char *buf;
275         unsigned char *ptr;
276         sense_reason_t rc = TCM_NO_SENSE;
277         u32 len = 4; /* Skip over RESERVED area in header */
278         int alua_access_state, primary = 0, valid_states;
279         u16 tg_pt_id, rtpi;
280
281         if (cmd->data_length < 4) {
282                 pr_warn("SET TARGET PORT GROUPS parameter list length %u too"
283                         " small\n", cmd->data_length);
284                 return TCM_INVALID_PARAMETER_LIST;
285         }
286
287         buf = transport_kmap_data_sg(cmd);
288         if (!buf)
289                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
290
291         /*
292          * Determine if explicit ALUA via SET_TARGET_PORT_GROUPS is allowed
293          * for the local tg_pt_gp.
294          */
295         spin_lock(&l_lun->lun_tg_pt_gp_lock);
296         l_tg_pt_gp = l_lun->lun_tg_pt_gp;
297         if (!l_tg_pt_gp) {
298                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
299                 pr_err("Unable to access l_lun->tg_pt_gp\n");
300                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
301                 goto out;
302         }
303
304         if (!(l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)) {
305                 spin_unlock(&l_lun->lun_tg_pt_gp_lock);
306                 pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
307                                 " while TPGS_EXPLICIT_ALUA is disabled\n");
308                 rc = TCM_UNSUPPORTED_SCSI_OPCODE;
309                 goto out;
310         }
311         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
312         spin_unlock(&l_lun->lun_tg_pt_gp_lock);
313
314         ptr = &buf[4]; /* Skip over RESERVED area in header */
315
316         while (len < cmd->data_length) {
317                 bool found = false;
318                 alua_access_state = (ptr[0] & 0x0f);
319                 /*
320                  * Check the received ALUA access state, and determine if
321                  * the state is a primary or secondary target port asymmetric
322                  * access state.
323                  */
324                 rc = core_alua_check_transition(alua_access_state, valid_states,
325                                                 &primary, 1);
326                 if (rc) {
327                         /*
328                          * If the SET TARGET PORT GROUPS attempts to establish
329                          * an invalid combination of target port asymmetric
330                          * access states or attempts to establish an
331                          * unsupported target port asymmetric access state,
332                          * then the command shall be terminated with CHECK
333                          * CONDITION status, with the sense key set to ILLEGAL
334                          * REQUEST, and the additional sense code set to INVALID
335                          * FIELD IN PARAMETER LIST.
336                          */
337                         goto out;
338                 }
339
340                 /*
341                  * If the ASYMMETRIC ACCESS STATE field (see table 267)
342                  * specifies a primary target port asymmetric access state,
343                  * then the TARGET PORT GROUP OR TARGET PORT field specifies
344                  * a primary target port group for which the primary target
345                  * port asymmetric access state shall be changed. If the
346                  * ASYMMETRIC ACCESS STATE field specifies a secondary target
347                  * port asymmetric access state, then the TARGET PORT GROUP OR
348                  * TARGET PORT field specifies the relative target port
349                  * identifier (see 3.1.120) of the target port for which the
350                  * secondary target port asymmetric access state shall be
351                  * changed.
352                  */
353                 if (primary) {
354                         tg_pt_id = get_unaligned_be16(ptr + 2);
355                         /*
356                          * Locate the matching target port group ID from
357                          * the global tg_pt_gp list
358                          */
359                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
360                         list_for_each_entry(tg_pt_gp,
361                                         &dev->t10_alua.tg_pt_gps_list,
362                                         tg_pt_gp_list) {
363                                 if (!tg_pt_gp->tg_pt_gp_valid_id)
364                                         continue;
365
366                                 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
367                                         continue;
368
369                                 atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
370
371                                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
372
373                                 if (!core_alua_do_port_transition(tg_pt_gp,
374                                                 dev, l_lun, nacl,
375                                                 alua_access_state, 1))
376                                         found = true;
377
378                                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
379                                 atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
380                                 break;
381                         }
382                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
383                 } else {
384                         struct se_lun *lun;
385
386                         /*
387                          * Extract the RELATIVE TARGET PORT IDENTIFIER to identify
388                          * the Target Port in question for the the incoming
389                          * SET_TARGET_PORT_GROUPS op.
390                          */
391                         rtpi = get_unaligned_be16(ptr + 2);
392                         /*
393                          * Locate the matching relative target port identifier
394                          * for the struct se_device storage object.
395                          */
396                         spin_lock(&dev->se_port_lock);
397                         list_for_each_entry(lun, &dev->dev_sep_list,
398                                                         lun_dev_link) {
399                                 if (lun->lun_rtpi != rtpi)
400                                         continue;
401
402                                 // XXX: racy unlock
403                                 spin_unlock(&dev->se_port_lock);
404
405                                 if (!core_alua_set_tg_pt_secondary_state(
406                                                 lun, 1, 1))
407                                         found = true;
408
409                                 spin_lock(&dev->se_port_lock);
410                                 break;
411                         }
412                         spin_unlock(&dev->se_port_lock);
413                 }
414
415                 if (!found) {
416                         rc = TCM_INVALID_PARAMETER_LIST;
417                         goto out;
418                 }
419
420                 ptr += 4;
421                 len += 4;
422         }
423
424 out:
425         transport_kunmap_data_sg(cmd);
426         if (!rc)
427                 target_complete_cmd(cmd, SAM_STAT_GOOD);
428         return rc;
429 }
430
431 static inline void core_alua_state_nonoptimized(
432         struct se_cmd *cmd,
433         unsigned char *cdb,
434         int nonop_delay_msecs)
435 {
436         /*
437          * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
438          * later to determine if processing of this cmd needs to be
439          * temporarily delayed for the Active/NonOptimized primary access state.
440          */
441         cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
442         cmd->alua_nonop_delay = nonop_delay_msecs;
443 }
444
445 static inline sense_reason_t core_alua_state_lba_dependent(
446         struct se_cmd *cmd,
447         u16 tg_pt_gp_id)
448 {
449         struct se_device *dev = cmd->se_dev;
450         u64 segment_size, segment_mult, sectors, lba;
451
452         /* Only need to check for cdb actually containing LBAs */
453         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB))
454                 return 0;
455
456         spin_lock(&dev->t10_alua.lba_map_lock);
457         segment_size = dev->t10_alua.lba_map_segment_size;
458         segment_mult = dev->t10_alua.lba_map_segment_multiplier;
459         sectors = cmd->data_length / dev->dev_attrib.block_size;
460
461         lba = cmd->t_task_lba;
462         while (lba < cmd->t_task_lba + sectors) {
463                 struct t10_alua_lba_map *cur_map = NULL, *map;
464                 struct t10_alua_lba_map_member *map_mem;
465
466                 list_for_each_entry(map, &dev->t10_alua.lba_map_list,
467                                     lba_map_list) {
468                         u64 start_lba, last_lba;
469                         u64 first_lba = map->lba_map_first_lba;
470
471                         if (segment_mult) {
472                                 u64 tmp = lba;
473                                 start_lba = do_div(tmp, segment_size * segment_mult);
474
475                                 last_lba = first_lba + segment_size - 1;
476                                 if (start_lba >= first_lba &&
477                                     start_lba <= last_lba) {
478                                         lba += segment_size;
479                                         cur_map = map;
480                                         break;
481                                 }
482                         } else {
483                                 last_lba = map->lba_map_last_lba;
484                                 if (lba >= first_lba && lba <= last_lba) {
485                                         lba = last_lba + 1;
486                                         cur_map = map;
487                                         break;
488                                 }
489                         }
490                 }
491                 if (!cur_map) {
492                         spin_unlock(&dev->t10_alua.lba_map_lock);
493                         return TCM_ALUA_TG_PT_UNAVAILABLE;
494                 }
495                 list_for_each_entry(map_mem, &cur_map->lba_map_mem_list,
496                                     lba_map_mem_list) {
497                         if (map_mem->lba_map_mem_alua_pg_id != tg_pt_gp_id)
498                                 continue;
499                         switch(map_mem->lba_map_mem_alua_state) {
500                         case ALUA_ACCESS_STATE_STANDBY:
501                                 spin_unlock(&dev->t10_alua.lba_map_lock);
502                                 return TCM_ALUA_TG_PT_STANDBY;
503                         case ALUA_ACCESS_STATE_UNAVAILABLE:
504                                 spin_unlock(&dev->t10_alua.lba_map_lock);
505                                 return TCM_ALUA_TG_PT_UNAVAILABLE;
506                         default:
507                                 break;
508                         }
509                 }
510         }
511         spin_unlock(&dev->t10_alua.lba_map_lock);
512         return 0;
513 }
514
515 static inline sense_reason_t core_alua_state_standby(
516         struct se_cmd *cmd,
517         unsigned char *cdb)
518 {
519         /*
520          * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
521          * spc4r17 section 5.9.2.4.4
522          */
523         switch (cdb[0]) {
524         case INQUIRY:
525         case LOG_SELECT:
526         case LOG_SENSE:
527         case MODE_SELECT:
528         case MODE_SENSE:
529         case REPORT_LUNS:
530         case RECEIVE_DIAGNOSTIC:
531         case SEND_DIAGNOSTIC:
532         case READ_CAPACITY:
533                 return 0;
534         case SERVICE_ACTION_IN_16:
535                 switch (cdb[1] & 0x1f) {
536                 case SAI_READ_CAPACITY_16:
537                         return 0;
538                 default:
539                         return TCM_ALUA_TG_PT_STANDBY;
540                 }
541         case MAINTENANCE_IN:
542                 switch (cdb[1] & 0x1f) {
543                 case MI_REPORT_TARGET_PGS:
544                         return 0;
545                 default:
546                         return TCM_ALUA_TG_PT_STANDBY;
547                 }
548         case MAINTENANCE_OUT:
549                 switch (cdb[1]) {
550                 case MO_SET_TARGET_PGS:
551                         return 0;
552                 default:
553                         return TCM_ALUA_TG_PT_STANDBY;
554                 }
555         case REQUEST_SENSE:
556         case PERSISTENT_RESERVE_IN:
557         case PERSISTENT_RESERVE_OUT:
558         case READ_BUFFER:
559         case WRITE_BUFFER:
560                 return 0;
561         default:
562                 return TCM_ALUA_TG_PT_STANDBY;
563         }
564
565         return 0;
566 }
567
568 static inline sense_reason_t core_alua_state_unavailable(
569         struct se_cmd *cmd,
570         unsigned char *cdb)
571 {
572         /*
573          * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
574          * spc4r17 section 5.9.2.4.5
575          */
576         switch (cdb[0]) {
577         case INQUIRY:
578         case REPORT_LUNS:
579                 return 0;
580         case MAINTENANCE_IN:
581                 switch (cdb[1] & 0x1f) {
582                 case MI_REPORT_TARGET_PGS:
583                         return 0;
584                 default:
585                         return TCM_ALUA_TG_PT_UNAVAILABLE;
586                 }
587         case MAINTENANCE_OUT:
588                 switch (cdb[1]) {
589                 case MO_SET_TARGET_PGS:
590                         return 0;
591                 default:
592                         return TCM_ALUA_TG_PT_UNAVAILABLE;
593                 }
594         case REQUEST_SENSE:
595         case READ_BUFFER:
596         case WRITE_BUFFER:
597                 return 0;
598         default:
599                 return TCM_ALUA_TG_PT_UNAVAILABLE;
600         }
601
602         return 0;
603 }
604
605 static inline sense_reason_t core_alua_state_transition(
606         struct se_cmd *cmd,
607         unsigned char *cdb)
608 {
609         /*
610          * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by
611          * spc4r17 section 5.9.2.5
612          */
613         switch (cdb[0]) {
614         case INQUIRY:
615         case REPORT_LUNS:
616                 return 0;
617         case MAINTENANCE_IN:
618                 switch (cdb[1] & 0x1f) {
619                 case MI_REPORT_TARGET_PGS:
620                         return 0;
621                 default:
622                         return TCM_ALUA_STATE_TRANSITION;
623                 }
624         case REQUEST_SENSE:
625         case READ_BUFFER:
626         case WRITE_BUFFER:
627                 return 0;
628         default:
629                 return TCM_ALUA_STATE_TRANSITION;
630         }
631
632         return 0;
633 }
634
635 /*
636  * return 1: Is used to signal LUN not accessible, and check condition/not ready
637  * return 0: Used to signal success
638  * return -1: Used to signal failure, and invalid cdb field
639  */
640 sense_reason_t
641 target_alua_state_check(struct se_cmd *cmd)
642 {
643         struct se_device *dev = cmd->se_dev;
644         unsigned char *cdb = cmd->t_task_cdb;
645         struct se_lun *lun = cmd->se_lun;
646         struct t10_alua_tg_pt_gp *tg_pt_gp;
647         int out_alua_state, nonop_delay_msecs;
648         u16 tg_pt_gp_id;
649         sense_reason_t rc = TCM_NO_SENSE;
650
651         if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)
652                 return 0;
653         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
654                 return 0;
655
656         /*
657          * First, check for a struct se_port specific secondary ALUA target port
658          * access state: OFFLINE
659          */
660         if (atomic_read(&lun->lun_tg_pt_secondary_offline)) {
661                 pr_debug("ALUA: Got secondary offline status for local"
662                                 " target port\n");
663                 return TCM_ALUA_OFFLINE;
664         }
665
666         if (!lun->lun_tg_pt_gp)
667                 return 0;
668
669         spin_lock(&lun->lun_tg_pt_gp_lock);
670         tg_pt_gp = lun->lun_tg_pt_gp;
671         out_alua_state = tg_pt_gp->tg_pt_gp_alua_access_state;
672         nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
673         tg_pt_gp_id = tg_pt_gp->tg_pt_gp_id;
674
675         spin_unlock(&lun->lun_tg_pt_gp_lock);
676         /*
677          * Process ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED in a separate conditional
678          * statement so the compiler knows explicitly to check this case first.
679          * For the Optimized ALUA access state case, we want to process the
680          * incoming fabric cmd ASAP..
681          */
682         if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED)
683                 return 0;
684
685         switch (out_alua_state) {
686         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
687                 core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs);
688                 break;
689         case ALUA_ACCESS_STATE_STANDBY:
690                 rc = core_alua_state_standby(cmd, cdb);
691                 break;
692         case ALUA_ACCESS_STATE_UNAVAILABLE:
693                 rc = core_alua_state_unavailable(cmd, cdb);
694                 break;
695         case ALUA_ACCESS_STATE_TRANSITION:
696                 rc = core_alua_state_transition(cmd, cdb);
697                 break;
698         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
699                 rc = core_alua_state_lba_dependent(cmd, tg_pt_gp_id);
700                 break;
701         /*
702          * OFFLINE is a secondary ALUA target port group access state, that is
703          * handled above with struct se_lun->lun_tg_pt_secondary_offline=1
704          */
705         case ALUA_ACCESS_STATE_OFFLINE:
706         default:
707                 pr_err("Unknown ALUA access state: 0x%02x\n",
708                                 out_alua_state);
709                 rc = TCM_INVALID_CDB_FIELD;
710         }
711
712         if (rc && rc != TCM_INVALID_CDB_FIELD) {
713                 pr_debug("[%s]: ALUA TG Port not available, "
714                         "SenseKey: NOT_READY, ASC/rc: 0x04/%d\n",
715                         cmd->se_tfo->fabric_name, rc);
716         }
717
718         return rc;
719 }
720
721 /*
722  * Check implicit and explicit ALUA state change request.
723  */
724 static sense_reason_t
725 core_alua_check_transition(int state, int valid, int *primary, int explicit)
726 {
727         /*
728          * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
729          * defined as primary target port asymmetric access states.
730          */
731         switch (state) {
732         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
733                 if (!(valid & ALUA_AO_SUP))
734                         goto not_supported;
735                 *primary = 1;
736                 break;
737         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
738                 if (!(valid & ALUA_AN_SUP))
739                         goto not_supported;
740                 *primary = 1;
741                 break;
742         case ALUA_ACCESS_STATE_STANDBY:
743                 if (!(valid & ALUA_S_SUP))
744                         goto not_supported;
745                 *primary = 1;
746                 break;
747         case ALUA_ACCESS_STATE_UNAVAILABLE:
748                 if (!(valid & ALUA_U_SUP))
749                         goto not_supported;
750                 *primary = 1;
751                 break;
752         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
753                 if (!(valid & ALUA_LBD_SUP))
754                         goto not_supported;
755                 *primary = 1;
756                 break;
757         case ALUA_ACCESS_STATE_OFFLINE:
758                 /*
759                  * OFFLINE state is defined as a secondary target port
760                  * asymmetric access state.
761                  */
762                 if (!(valid & ALUA_O_SUP))
763                         goto not_supported;
764                 *primary = 0;
765                 break;
766         case ALUA_ACCESS_STATE_TRANSITION:
767                 if (!(valid & ALUA_T_SUP) || explicit)
768                         /*
769                          * Transitioning is set internally and by tcmu daemon,
770                          * and cannot be selected through a STPG.
771                          */
772                         goto not_supported;
773                 *primary = 0;
774                 break;
775         default:
776                 pr_err("Unknown ALUA access state: 0x%02x\n", state);
777                 return TCM_INVALID_PARAMETER_LIST;
778         }
779
780         return 0;
781
782 not_supported:
783         pr_err("ALUA access state %s not supported",
784                core_alua_dump_state(state));
785         return TCM_INVALID_PARAMETER_LIST;
786 }
787
788 static char *core_alua_dump_state(int state)
789 {
790         switch (state) {
791         case ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED:
792                 return "Active/Optimized";
793         case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
794                 return "Active/NonOptimized";
795         case ALUA_ACCESS_STATE_LBA_DEPENDENT:
796                 return "LBA Dependent";
797         case ALUA_ACCESS_STATE_STANDBY:
798                 return "Standby";
799         case ALUA_ACCESS_STATE_UNAVAILABLE:
800                 return "Unavailable";
801         case ALUA_ACCESS_STATE_OFFLINE:
802                 return "Offline";
803         case ALUA_ACCESS_STATE_TRANSITION:
804                 return "Transitioning";
805         default:
806                 return "Unknown";
807         }
808
809         return NULL;
810 }
811
812 char *core_alua_dump_status(int status)
813 {
814         switch (status) {
815         case ALUA_STATUS_NONE:
816                 return "None";
817         case ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG:
818                 return "Altered by Explicit STPG";
819         case ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA:
820                 return "Altered by Implicit ALUA";
821         default:
822                 return "Unknown";
823         }
824
825         return NULL;
826 }
827
828 /*
829  * Used by fabric modules to determine when we need to delay processing
830  * for the Active/NonOptimized paths..
831  */
832 int core_alua_check_nonop_delay(
833         struct se_cmd *cmd)
834 {
835         if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
836                 return 0;
837         /*
838          * The ALUA Active/NonOptimized access state delay can be disabled
839          * in via configfs with a value of zero
840          */
841         if (!cmd->alua_nonop_delay)
842                 return 0;
843         /*
844          * struct se_cmd->alua_nonop_delay gets set by a target port group
845          * defined interval in core_alua_state_nonoptimized()
846          */
847         msleep_interruptible(cmd->alua_nonop_delay);
848         return 0;
849 }
850 EXPORT_SYMBOL(core_alua_check_nonop_delay);
851
852 static int core_alua_write_tpg_metadata(
853         const char *path,
854         unsigned char *md_buf,
855         u32 md_buf_len)
856 {
857         struct file *file = filp_open(path, O_RDWR | O_CREAT | O_TRUNC, 0600);
858         loff_t pos = 0;
859         int ret;
860
861         if (IS_ERR(file)) {
862                 pr_err("filp_open(%s) for ALUA metadata failed\n", path);
863                 return -ENODEV;
864         }
865         ret = kernel_write(file, md_buf, md_buf_len, &pos);
866         if (ret < 0)
867                 pr_err("Error writing ALUA metadata file: %s\n", path);
868         fput(file);
869         return (ret < 0) ? -EIO : 0;
870 }
871
872 static int core_alua_update_tpg_primary_metadata(
873         struct t10_alua_tg_pt_gp *tg_pt_gp)
874 {
875         unsigned char *md_buf;
876         struct t10_wwn *wwn = &tg_pt_gp->tg_pt_gp_dev->t10_wwn;
877         char *path;
878         int len, rc;
879
880         lockdep_assert_held(&tg_pt_gp->tg_pt_gp_transition_mutex);
881
882         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
883         if (!md_buf) {
884                 pr_err("Unable to allocate buf for ALUA metadata\n");
885                 return -ENOMEM;
886         }
887
888         len = snprintf(md_buf, ALUA_MD_BUF_LEN,
889                         "tg_pt_gp_id=%hu\n"
890                         "alua_access_state=0x%02x\n"
891                         "alua_access_status=0x%02x\n",
892                         tg_pt_gp->tg_pt_gp_id,
893                         tg_pt_gp->tg_pt_gp_alua_access_state,
894                         tg_pt_gp->tg_pt_gp_alua_access_status);
895
896         rc = -ENOMEM;
897         path = kasprintf(GFP_KERNEL, "%s/alua/tpgs_%s/%s", db_root,
898                         &wwn->unit_serial[0],
899                         config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
900         if (path) {
901                 rc = core_alua_write_tpg_metadata(path, md_buf, len);
902                 kfree(path);
903         }
904         kfree(md_buf);
905         return rc;
906 }
907
908 static void core_alua_queue_state_change_ua(struct t10_alua_tg_pt_gp *tg_pt_gp)
909 {
910         struct se_dev_entry *se_deve;
911         struct se_lun *lun;
912         struct se_lun_acl *lacl;
913
914         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
915         list_for_each_entry(lun, &tg_pt_gp->tg_pt_gp_lun_list,
916                                 lun_tg_pt_gp_link) {
917                 /*
918                  * After an implicit target port asymmetric access state
919                  * change, a device server shall establish a unit attention
920                  * condition for the initiator port associated with every I_T
921                  * nexus with the additional sense code set to ASYMMETRIC
922                  * ACCESS STATE CHANGED.
923                  *
924                  * After an explicit target port asymmetric access state
925                  * change, a device server shall establish a unit attention
926                  * condition with the additional sense code set to ASYMMETRIC
927                  * ACCESS STATE CHANGED for the initiator port associated with
928                  * every I_T nexus other than the I_T nexus on which the SET
929                  * TARGET PORT GROUPS command
930                  */
931                 if (!percpu_ref_tryget_live(&lun->lun_ref))
932                         continue;
933                 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
934
935                 spin_lock(&lun->lun_deve_lock);
936                 list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link) {
937                         lacl = rcu_dereference_check(se_deve->se_lun_acl,
938                                         lockdep_is_held(&lun->lun_deve_lock));
939
940                         /*
941                          * spc4r37 p.242:
942                          * After an explicit target port asymmetric access
943                          * state change, a device server shall establish a
944                          * unit attention condition with the additional sense
945                          * code set to ASYMMETRIC ACCESS STATE CHANGED for
946                          * the initiator port associated with every I_T nexus
947                          * other than the I_T nexus on which the SET TARGET
948                          * PORT GROUPS command was received.
949                          */
950                         if ((tg_pt_gp->tg_pt_gp_alua_access_status ==
951                              ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
952                            (tg_pt_gp->tg_pt_gp_alua_lun != NULL) &&
953                             (tg_pt_gp->tg_pt_gp_alua_lun == lun))
954                                 continue;
955
956                         /*
957                          * se_deve->se_lun_acl pointer may be NULL for a
958                          * entry created without explicit Node+MappedLUN ACLs
959                          */
960                         if (lacl && (tg_pt_gp->tg_pt_gp_alua_nacl != NULL) &&
961                             (tg_pt_gp->tg_pt_gp_alua_nacl == lacl->se_lun_nacl))
962                                 continue;
963
964                         core_scsi3_ua_allocate(se_deve, 0x2A,
965                                 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
966                 }
967                 spin_unlock(&lun->lun_deve_lock);
968
969                 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
970                 percpu_ref_put(&lun->lun_ref);
971         }
972         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
973 }
974
975 static int core_alua_do_transition_tg_pt(
976         struct t10_alua_tg_pt_gp *tg_pt_gp,
977         int new_state,
978         int explicit)
979 {
980         int prev_state;
981
982         mutex_lock(&tg_pt_gp->tg_pt_gp_transition_mutex);
983         /* Nothing to be done here */
984         if (tg_pt_gp->tg_pt_gp_alua_access_state == new_state) {
985                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
986                 return 0;
987         }
988
989         if (explicit && new_state == ALUA_ACCESS_STATE_TRANSITION) {
990                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
991                 return -EAGAIN;
992         }
993
994         /*
995          * Save the old primary ALUA access state, and set the current state
996          * to ALUA_ACCESS_STATE_TRANSITION.
997          */
998         prev_state = tg_pt_gp->tg_pt_gp_alua_access_state;
999         tg_pt_gp->tg_pt_gp_alua_access_state = ALUA_ACCESS_STATE_TRANSITION;
1000         tg_pt_gp->tg_pt_gp_alua_access_status = (explicit) ?
1001                                 ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1002                                 ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1003
1004         core_alua_queue_state_change_ua(tg_pt_gp);
1005
1006         if (new_state == ALUA_ACCESS_STATE_TRANSITION) {
1007                 mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1008                 return 0;
1009         }
1010
1011         /*
1012          * Check for the optional ALUA primary state transition delay
1013          */
1014         if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
1015                 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1016
1017         /*
1018          * Set the current primary ALUA access state to the requested new state
1019          */
1020         tg_pt_gp->tg_pt_gp_alua_access_state = new_state;
1021
1022         /*
1023          * Update the ALUA metadata buf that has been allocated in
1024          * core_alua_do_port_transition(), this metadata will be written
1025          * to struct file.
1026          *
1027          * Note that there is the case where we do not want to update the
1028          * metadata when the saved metadata is being parsed in userspace
1029          * when setting the existing port access state and access status.
1030          *
1031          * Also note that the failure to write out the ALUA metadata to
1032          * struct file does NOT affect the actual ALUA transition.
1033          */
1034         if (tg_pt_gp->tg_pt_gp_write_metadata) {
1035                 core_alua_update_tpg_primary_metadata(tg_pt_gp);
1036         }
1037
1038         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1039                 " from primary access state %s to %s\n", (explicit) ? "explicit" :
1040                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1041                 tg_pt_gp->tg_pt_gp_id,
1042                 core_alua_dump_state(prev_state),
1043                 core_alua_dump_state(new_state));
1044
1045         core_alua_queue_state_change_ua(tg_pt_gp);
1046
1047         mutex_unlock(&tg_pt_gp->tg_pt_gp_transition_mutex);
1048         return 0;
1049 }
1050
1051 int core_alua_do_port_transition(
1052         struct t10_alua_tg_pt_gp *l_tg_pt_gp,
1053         struct se_device *l_dev,
1054         struct se_lun *l_lun,
1055         struct se_node_acl *l_nacl,
1056         int new_state,
1057         int explicit)
1058 {
1059         struct se_device *dev;
1060         struct t10_alua_lu_gp *lu_gp;
1061         struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
1062         struct t10_alua_tg_pt_gp *tg_pt_gp;
1063         int primary, valid_states, rc = 0;
1064
1065         if (l_dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA)
1066                 return -ENODEV;
1067
1068         valid_states = l_tg_pt_gp->tg_pt_gp_alua_supported_states;
1069         if (core_alua_check_transition(new_state, valid_states, &primary,
1070                                        explicit) != 0)
1071                 return -EINVAL;
1072
1073         local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
1074         spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
1075         lu_gp = local_lu_gp_mem->lu_gp;
1076         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1077         spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
1078         /*
1079          * For storage objects that are members of the 'default_lu_gp',
1080          * we only do transition on the passed *l_tp_pt_gp, and not
1081          * on all of the matching target port groups IDs in default_lu_gp.
1082          */
1083         if (!lu_gp->lu_gp_id) {
1084                 /*
1085                  * core_alua_do_transition_tg_pt() will always return
1086                  * success.
1087                  */
1088                 l_tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1089                 l_tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1090                 rc = core_alua_do_transition_tg_pt(l_tg_pt_gp,
1091                                                    new_state, explicit);
1092                 atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1093                 return rc;
1094         }
1095         /*
1096          * For all other LU groups aside from 'default_lu_gp', walk all of
1097          * the associated storage objects looking for a matching target port
1098          * group ID from the local target port group.
1099          */
1100         spin_lock(&lu_gp->lu_gp_lock);
1101         list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
1102                                 lu_gp_mem_list) {
1103
1104                 dev = lu_gp_mem->lu_gp_mem_dev;
1105                 atomic_inc_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1106                 spin_unlock(&lu_gp->lu_gp_lock);
1107
1108                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1109                 list_for_each_entry(tg_pt_gp,
1110                                 &dev->t10_alua.tg_pt_gps_list,
1111                                 tg_pt_gp_list) {
1112
1113                         if (!tg_pt_gp->tg_pt_gp_valid_id)
1114                                 continue;
1115                         /*
1116                          * If the target behavior port asymmetric access state
1117                          * is changed for any target port group accessible via
1118                          * a logical unit within a LU group, the target port
1119                          * behavior group asymmetric access states for the same
1120                          * target port group accessible via other logical units
1121                          * in that LU group will also change.
1122                          */
1123                         if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
1124                                 continue;
1125
1126                         if (l_tg_pt_gp == tg_pt_gp) {
1127                                 tg_pt_gp->tg_pt_gp_alua_lun = l_lun;
1128                                 tg_pt_gp->tg_pt_gp_alua_nacl = l_nacl;
1129                         } else {
1130                                 tg_pt_gp->tg_pt_gp_alua_lun = NULL;
1131                                 tg_pt_gp->tg_pt_gp_alua_nacl = NULL;
1132                         }
1133                         atomic_inc_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1134                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1135                         /*
1136                          * core_alua_do_transition_tg_pt() will always return
1137                          * success.
1138                          */
1139                         rc = core_alua_do_transition_tg_pt(tg_pt_gp,
1140                                         new_state, explicit);
1141
1142                         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1143                         atomic_dec_mb(&tg_pt_gp->tg_pt_gp_ref_cnt);
1144                         if (rc)
1145                                 break;
1146                 }
1147                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1148
1149                 spin_lock(&lu_gp->lu_gp_lock);
1150                 atomic_dec_mb(&lu_gp_mem->lu_gp_mem_ref_cnt);
1151         }
1152         spin_unlock(&lu_gp->lu_gp_lock);
1153
1154         if (!rc) {
1155                 pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
1156                          " Group IDs: %hu %s transition to primary state: %s\n",
1157                          config_item_name(&lu_gp->lu_gp_group.cg_item),
1158                          l_tg_pt_gp->tg_pt_gp_id,
1159                          (explicit) ? "explicit" : "implicit",
1160                          core_alua_dump_state(new_state));
1161         }
1162
1163         atomic_dec_mb(&lu_gp->lu_gp_ref_cnt);
1164         return rc;
1165 }
1166
1167 static int core_alua_update_tpg_secondary_metadata(struct se_lun *lun)
1168 {
1169         struct se_portal_group *se_tpg = lun->lun_tpg;
1170         unsigned char *md_buf;
1171         char *path;
1172         int len, rc;
1173
1174         mutex_lock(&lun->lun_tg_pt_md_mutex);
1175
1176         md_buf = kzalloc(ALUA_MD_BUF_LEN, GFP_KERNEL);
1177         if (!md_buf) {
1178                 pr_err("Unable to allocate buf for ALUA metadata\n");
1179                 rc = -ENOMEM;
1180                 goto out_unlock;
1181         }
1182
1183         len = snprintf(md_buf, ALUA_MD_BUF_LEN, "alua_tg_pt_offline=%d\n"
1184                         "alua_tg_pt_status=0x%02x\n",
1185                         atomic_read(&lun->lun_tg_pt_secondary_offline),
1186                         lun->lun_tg_pt_secondary_stat);
1187
1188         if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL) {
1189                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s+%hu/lun_%llu",
1190                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1191                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1192                                 se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg),
1193                                 lun->unpacked_lun);
1194         } else {
1195                 path = kasprintf(GFP_KERNEL, "%s/alua/%s/%s/lun_%llu",
1196                                 db_root, se_tpg->se_tpg_tfo->fabric_name,
1197                                 se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg),
1198                                 lun->unpacked_lun);
1199         }
1200         if (!path) {
1201                 rc = -ENOMEM;
1202                 goto out_free;
1203         }
1204
1205         rc = core_alua_write_tpg_metadata(path, md_buf, len);
1206         kfree(path);
1207 out_free:
1208         kfree(md_buf);
1209 out_unlock:
1210         mutex_unlock(&lun->lun_tg_pt_md_mutex);
1211         return rc;
1212 }
1213
1214 static int core_alua_set_tg_pt_secondary_state(
1215         struct se_lun *lun,
1216         int explicit,
1217         int offline)
1218 {
1219         struct t10_alua_tg_pt_gp *tg_pt_gp;
1220         int trans_delay_msecs;
1221
1222         spin_lock(&lun->lun_tg_pt_gp_lock);
1223         tg_pt_gp = lun->lun_tg_pt_gp;
1224         if (!tg_pt_gp) {
1225                 spin_unlock(&lun->lun_tg_pt_gp_lock);
1226                 pr_err("Unable to complete secondary state"
1227                                 " transition\n");
1228                 return -EINVAL;
1229         }
1230         trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
1231         /*
1232          * Set the secondary ALUA target port access state to OFFLINE
1233          * or release the previously secondary state for struct se_lun
1234          */
1235         if (offline)
1236                 atomic_set(&lun->lun_tg_pt_secondary_offline, 1);
1237         else
1238                 atomic_set(&lun->lun_tg_pt_secondary_offline, 0);
1239
1240         lun->lun_tg_pt_secondary_stat = (explicit) ?
1241                         ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG :
1242                         ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA;
1243
1244         pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
1245                 " to secondary access state: %s\n", (explicit) ? "explicit" :
1246                 "implicit", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1247                 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1248
1249         spin_unlock(&lun->lun_tg_pt_gp_lock);
1250         /*
1251          * Do the optional transition delay after we set the secondary
1252          * ALUA access state.
1253          */
1254         if (trans_delay_msecs != 0)
1255                 msleep_interruptible(trans_delay_msecs);
1256         /*
1257          * See if we need to update the ALUA fabric port metadata for
1258          * secondary state and status
1259          */
1260         if (lun->lun_tg_pt_secondary_write_md)
1261                 core_alua_update_tpg_secondary_metadata(lun);
1262
1263         return 0;
1264 }
1265
1266 struct t10_alua_lba_map *
1267 core_alua_allocate_lba_map(struct list_head *list,
1268                            u64 first_lba, u64 last_lba)
1269 {
1270         struct t10_alua_lba_map *lba_map;
1271
1272         lba_map = kmem_cache_zalloc(t10_alua_lba_map_cache, GFP_KERNEL);
1273         if (!lba_map) {
1274                 pr_err("Unable to allocate struct t10_alua_lba_map\n");
1275                 return ERR_PTR(-ENOMEM);
1276         }
1277         INIT_LIST_HEAD(&lba_map->lba_map_mem_list);
1278         lba_map->lba_map_first_lba = first_lba;
1279         lba_map->lba_map_last_lba = last_lba;
1280
1281         list_add_tail(&lba_map->lba_map_list, list);
1282         return lba_map;
1283 }
1284
1285 int
1286 core_alua_allocate_lba_map_mem(struct t10_alua_lba_map *lba_map,
1287                                int pg_id, int state)
1288 {
1289         struct t10_alua_lba_map_member *lba_map_mem;
1290
1291         list_for_each_entry(lba_map_mem, &lba_map->lba_map_mem_list,
1292                             lba_map_mem_list) {
1293                 if (lba_map_mem->lba_map_mem_alua_pg_id == pg_id) {
1294                         pr_err("Duplicate pg_id %d in lba_map\n", pg_id);
1295                         return -EINVAL;
1296                 }
1297         }
1298
1299         lba_map_mem = kmem_cache_zalloc(t10_alua_lba_map_mem_cache, GFP_KERNEL);
1300         if (!lba_map_mem) {
1301                 pr_err("Unable to allocate struct t10_alua_lba_map_mem\n");
1302                 return -ENOMEM;
1303         }
1304         lba_map_mem->lba_map_mem_alua_state = state;
1305         lba_map_mem->lba_map_mem_alua_pg_id = pg_id;
1306
1307         list_add_tail(&lba_map_mem->lba_map_mem_list,
1308                       &lba_map->lba_map_mem_list);
1309         return 0;
1310 }
1311
1312 void
1313 core_alua_free_lba_map(struct list_head *lba_list)
1314 {
1315         struct t10_alua_lba_map *lba_map, *lba_map_tmp;
1316         struct t10_alua_lba_map_member *lba_map_mem, *lba_map_mem_tmp;
1317
1318         list_for_each_entry_safe(lba_map, lba_map_tmp, lba_list,
1319                                  lba_map_list) {
1320                 list_for_each_entry_safe(lba_map_mem, lba_map_mem_tmp,
1321                                          &lba_map->lba_map_mem_list,
1322                                          lba_map_mem_list) {
1323                         list_del(&lba_map_mem->lba_map_mem_list);
1324                         kmem_cache_free(t10_alua_lba_map_mem_cache,
1325                                         lba_map_mem);
1326                 }
1327                 list_del(&lba_map->lba_map_list);
1328                 kmem_cache_free(t10_alua_lba_map_cache, lba_map);
1329         }
1330 }
1331
1332 void
1333 core_alua_set_lba_map(struct se_device *dev, struct list_head *lba_map_list,
1334                       int segment_size, int segment_mult)
1335 {
1336         struct list_head old_lba_map_list;
1337         struct t10_alua_tg_pt_gp *tg_pt_gp;
1338         int activate = 0, supported;
1339
1340         INIT_LIST_HEAD(&old_lba_map_list);
1341         spin_lock(&dev->t10_alua.lba_map_lock);
1342         dev->t10_alua.lba_map_segment_size = segment_size;
1343         dev->t10_alua.lba_map_segment_multiplier = segment_mult;
1344         list_splice_init(&dev->t10_alua.lba_map_list, &old_lba_map_list);
1345         if (lba_map_list) {
1346                 list_splice_init(lba_map_list, &dev->t10_alua.lba_map_list);
1347                 activate = 1;
1348         }
1349         spin_unlock(&dev->t10_alua.lba_map_lock);
1350         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1351         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1352                             tg_pt_gp_list) {
1353
1354                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1355                         continue;
1356                 supported = tg_pt_gp->tg_pt_gp_alua_supported_states;
1357                 if (activate)
1358                         supported |= ALUA_LBD_SUP;
1359                 else
1360                         supported &= ~ALUA_LBD_SUP;
1361                 tg_pt_gp->tg_pt_gp_alua_supported_states = supported;
1362         }
1363         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1364         core_alua_free_lba_map(&old_lba_map_list);
1365 }
1366
1367 struct t10_alua_lu_gp *
1368 core_alua_allocate_lu_gp(const char *name, int def_group)
1369 {
1370         struct t10_alua_lu_gp *lu_gp;
1371
1372         lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1373         if (!lu_gp) {
1374                 pr_err("Unable to allocate struct t10_alua_lu_gp\n");
1375                 return ERR_PTR(-ENOMEM);
1376         }
1377         INIT_LIST_HEAD(&lu_gp->lu_gp_node);
1378         INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1379         spin_lock_init(&lu_gp->lu_gp_lock);
1380         atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1381
1382         if (def_group) {
1383                 lu_gp->lu_gp_id = alua_lu_gps_counter++;
1384                 lu_gp->lu_gp_valid_id = 1;
1385                 alua_lu_gps_count++;
1386         }
1387
1388         return lu_gp;
1389 }
1390
1391 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1392 {
1393         struct t10_alua_lu_gp *lu_gp_tmp;
1394         u16 lu_gp_id_tmp;
1395         /*
1396          * The lu_gp->lu_gp_id may only be set once..
1397          */
1398         if (lu_gp->lu_gp_valid_id) {
1399                 pr_warn("ALUA LU Group already has a valid ID,"
1400                         " ignoring request\n");
1401                 return -EINVAL;
1402         }
1403
1404         spin_lock(&lu_gps_lock);
1405         if (alua_lu_gps_count == 0x0000ffff) {
1406                 pr_err("Maximum ALUA alua_lu_gps_count:"
1407                                 " 0x0000ffff reached\n");
1408                 spin_unlock(&lu_gps_lock);
1409                 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1410                 return -ENOSPC;
1411         }
1412 again:
1413         lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1414                                 alua_lu_gps_counter++;
1415
1416         list_for_each_entry(lu_gp_tmp, &lu_gps_list, lu_gp_node) {
1417                 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1418                         if (!lu_gp_id)
1419                                 goto again;
1420
1421                         pr_warn("ALUA Logical Unit Group ID: %hu"
1422                                 " already exists, ignoring request\n",
1423                                 lu_gp_id);
1424                         spin_unlock(&lu_gps_lock);
1425                         return -EINVAL;
1426                 }
1427         }
1428
1429         lu_gp->lu_gp_id = lu_gp_id_tmp;
1430         lu_gp->lu_gp_valid_id = 1;
1431         list_add_tail(&lu_gp->lu_gp_node, &lu_gps_list);
1432         alua_lu_gps_count++;
1433         spin_unlock(&lu_gps_lock);
1434
1435         return 0;
1436 }
1437
1438 static struct t10_alua_lu_gp_member *
1439 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1440 {
1441         struct t10_alua_lu_gp_member *lu_gp_mem;
1442
1443         lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1444         if (!lu_gp_mem) {
1445                 pr_err("Unable to allocate struct t10_alua_lu_gp_member\n");
1446                 return ERR_PTR(-ENOMEM);
1447         }
1448         INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1449         spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1450         atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1451
1452         lu_gp_mem->lu_gp_mem_dev = dev;
1453         dev->dev_alua_lu_gp_mem = lu_gp_mem;
1454
1455         return lu_gp_mem;
1456 }
1457
1458 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1459 {
1460         struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1461         /*
1462          * Once we have reached this point, config_item_put() has
1463          * already been called from target_core_alua_drop_lu_gp().
1464          *
1465          * Here, we remove the *lu_gp from the global list so that
1466          * no associations can be made while we are releasing
1467          * struct t10_alua_lu_gp.
1468          */
1469         spin_lock(&lu_gps_lock);
1470         list_del(&lu_gp->lu_gp_node);
1471         alua_lu_gps_count--;
1472         spin_unlock(&lu_gps_lock);
1473         /*
1474          * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1475          * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1476          * released with core_alua_put_lu_gp_from_name()
1477          */
1478         while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1479                 cpu_relax();
1480         /*
1481          * Release reference to struct t10_alua_lu_gp * from all associated
1482          * struct se_device.
1483          */
1484         spin_lock(&lu_gp->lu_gp_lock);
1485         list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1486                                 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1487                 if (lu_gp_mem->lu_gp_assoc) {
1488                         list_del(&lu_gp_mem->lu_gp_mem_list);
1489                         lu_gp->lu_gp_members--;
1490                         lu_gp_mem->lu_gp_assoc = 0;
1491                 }
1492                 spin_unlock(&lu_gp->lu_gp_lock);
1493                 /*
1494                  *
1495                  * lu_gp_mem is associated with a single
1496                  * struct se_device->dev_alua_lu_gp_mem, and is released when
1497                  * struct se_device is released via core_alua_free_lu_gp_mem().
1498                  *
1499                  * If the passed lu_gp does NOT match the default_lu_gp, assume
1500                  * we want to re-associate a given lu_gp_mem with default_lu_gp.
1501                  */
1502                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1503                 if (lu_gp != default_lu_gp)
1504                         __core_alua_attach_lu_gp_mem(lu_gp_mem,
1505                                         default_lu_gp);
1506                 else
1507                         lu_gp_mem->lu_gp = NULL;
1508                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1509
1510                 spin_lock(&lu_gp->lu_gp_lock);
1511         }
1512         spin_unlock(&lu_gp->lu_gp_lock);
1513
1514         kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1515 }
1516
1517 void core_alua_free_lu_gp_mem(struct se_device *dev)
1518 {
1519         struct t10_alua_lu_gp *lu_gp;
1520         struct t10_alua_lu_gp_member *lu_gp_mem;
1521
1522         lu_gp_mem = dev->dev_alua_lu_gp_mem;
1523         if (!lu_gp_mem)
1524                 return;
1525
1526         while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1527                 cpu_relax();
1528
1529         spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1530         lu_gp = lu_gp_mem->lu_gp;
1531         if (lu_gp) {
1532                 spin_lock(&lu_gp->lu_gp_lock);
1533                 if (lu_gp_mem->lu_gp_assoc) {
1534                         list_del(&lu_gp_mem->lu_gp_mem_list);
1535                         lu_gp->lu_gp_members--;
1536                         lu_gp_mem->lu_gp_assoc = 0;
1537                 }
1538                 spin_unlock(&lu_gp->lu_gp_lock);
1539                 lu_gp_mem->lu_gp = NULL;
1540         }
1541         spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1542
1543         kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1544 }
1545
1546 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1547 {
1548         struct t10_alua_lu_gp *lu_gp;
1549         struct config_item *ci;
1550
1551         spin_lock(&lu_gps_lock);
1552         list_for_each_entry(lu_gp, &lu_gps_list, lu_gp_node) {
1553                 if (!lu_gp->lu_gp_valid_id)
1554                         continue;
1555                 ci = &lu_gp->lu_gp_group.cg_item;
1556                 if (!strcmp(config_item_name(ci), name)) {
1557                         atomic_inc(&lu_gp->lu_gp_ref_cnt);
1558                         spin_unlock(&lu_gps_lock);
1559                         return lu_gp;
1560                 }
1561         }
1562         spin_unlock(&lu_gps_lock);
1563
1564         return NULL;
1565 }
1566
1567 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1568 {
1569         spin_lock(&lu_gps_lock);
1570         atomic_dec(&lu_gp->lu_gp_ref_cnt);
1571         spin_unlock(&lu_gps_lock);
1572 }
1573
1574 /*
1575  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1576  */
1577 void __core_alua_attach_lu_gp_mem(
1578         struct t10_alua_lu_gp_member *lu_gp_mem,
1579         struct t10_alua_lu_gp *lu_gp)
1580 {
1581         spin_lock(&lu_gp->lu_gp_lock);
1582         lu_gp_mem->lu_gp = lu_gp;
1583         lu_gp_mem->lu_gp_assoc = 1;
1584         list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1585         lu_gp->lu_gp_members++;
1586         spin_unlock(&lu_gp->lu_gp_lock);
1587 }
1588
1589 /*
1590  * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1591  */
1592 void __core_alua_drop_lu_gp_mem(
1593         struct t10_alua_lu_gp_member *lu_gp_mem,
1594         struct t10_alua_lu_gp *lu_gp)
1595 {
1596         spin_lock(&lu_gp->lu_gp_lock);
1597         list_del(&lu_gp_mem->lu_gp_mem_list);
1598         lu_gp_mem->lu_gp = NULL;
1599         lu_gp_mem->lu_gp_assoc = 0;
1600         lu_gp->lu_gp_members--;
1601         spin_unlock(&lu_gp->lu_gp_lock);
1602 }
1603
1604 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(struct se_device *dev,
1605                 const char *name, int def_group)
1606 {
1607         struct t10_alua_tg_pt_gp *tg_pt_gp;
1608
1609         tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1610         if (!tg_pt_gp) {
1611                 pr_err("Unable to allocate struct t10_alua_tg_pt_gp\n");
1612                 return NULL;
1613         }
1614         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1615         INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_lun_list);
1616         mutex_init(&tg_pt_gp->tg_pt_gp_transition_mutex);
1617         spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1618         atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1619         tg_pt_gp->tg_pt_gp_dev = dev;
1620         tg_pt_gp->tg_pt_gp_alua_access_state =
1621                         ALUA_ACCESS_STATE_ACTIVE_OPTIMIZED;
1622         /*
1623          * Enable both explicit and implicit ALUA support by default
1624          */
1625         tg_pt_gp->tg_pt_gp_alua_access_type =
1626                         TPGS_EXPLICIT_ALUA | TPGS_IMPLICIT_ALUA;
1627         /*
1628          * Set the default Active/NonOptimized Delay in milliseconds
1629          */
1630         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1631         tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1632         tg_pt_gp->tg_pt_gp_implicit_trans_secs = ALUA_DEFAULT_IMPLICIT_TRANS_SECS;
1633
1634         /*
1635          * Enable all supported states
1636          */
1637         tg_pt_gp->tg_pt_gp_alua_supported_states =
1638             ALUA_T_SUP | ALUA_O_SUP |
1639             ALUA_U_SUP | ALUA_S_SUP | ALUA_AN_SUP | ALUA_AO_SUP;
1640
1641         if (def_group) {
1642                 spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1643                 tg_pt_gp->tg_pt_gp_id =
1644                                 dev->t10_alua.alua_tg_pt_gps_counter++;
1645                 tg_pt_gp->tg_pt_gp_valid_id = 1;
1646                 dev->t10_alua.alua_tg_pt_gps_count++;
1647                 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1648                               &dev->t10_alua.tg_pt_gps_list);
1649                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1650         }
1651
1652         return tg_pt_gp;
1653 }
1654
1655 int core_alua_set_tg_pt_gp_id(
1656         struct t10_alua_tg_pt_gp *tg_pt_gp,
1657         u16 tg_pt_gp_id)
1658 {
1659         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1660         struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1661         u16 tg_pt_gp_id_tmp;
1662
1663         /*
1664          * The tg_pt_gp->tg_pt_gp_id may only be set once..
1665          */
1666         if (tg_pt_gp->tg_pt_gp_valid_id) {
1667                 pr_warn("ALUA TG PT Group already has a valid ID,"
1668                         " ignoring request\n");
1669                 return -EINVAL;
1670         }
1671
1672         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1673         if (dev->t10_alua.alua_tg_pt_gps_count == 0x0000ffff) {
1674                 pr_err("Maximum ALUA alua_tg_pt_gps_count:"
1675                         " 0x0000ffff reached\n");
1676                 spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1677                 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
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                         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         kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1766 }
1767
1768 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1769                 struct se_device *dev, const char *name)
1770 {
1771         struct t10_alua_tg_pt_gp *tg_pt_gp;
1772         struct config_item *ci;
1773
1774         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1775         list_for_each_entry(tg_pt_gp, &dev->t10_alua.tg_pt_gps_list,
1776                         tg_pt_gp_list) {
1777                 if (!tg_pt_gp->tg_pt_gp_valid_id)
1778                         continue;
1779                 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1780                 if (!strcmp(config_item_name(ci), name)) {
1781                         atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1782                         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1783                         return tg_pt_gp;
1784                 }
1785         }
1786         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1787
1788         return NULL;
1789 }
1790
1791 static void core_alua_put_tg_pt_gp_from_name(
1792         struct t10_alua_tg_pt_gp *tg_pt_gp)
1793 {
1794         struct se_device *dev = tg_pt_gp->tg_pt_gp_dev;
1795
1796         spin_lock(&dev->t10_alua.tg_pt_gps_lock);
1797         atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1798         spin_unlock(&dev->t10_alua.tg_pt_gps_lock);
1799 }
1800
1801 static void __target_attach_tg_pt_gp(struct se_lun *lun,
1802                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1803 {
1804         struct se_dev_entry *se_deve;
1805
1806         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1807
1808         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1809         lun->lun_tg_pt_gp = tg_pt_gp;
1810         list_add_tail(&lun->lun_tg_pt_gp_link, &tg_pt_gp->tg_pt_gp_lun_list);
1811         tg_pt_gp->tg_pt_gp_members++;
1812         spin_lock(&lun->lun_deve_lock);
1813         list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
1814                 core_scsi3_ua_allocate(se_deve, 0x3f,
1815                                        ASCQ_3FH_INQUIRY_DATA_HAS_CHANGED);
1816         spin_unlock(&lun->lun_deve_lock);
1817         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1818 }
1819
1820 void target_attach_tg_pt_gp(struct se_lun *lun,
1821                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1822 {
1823         spin_lock(&lun->lun_tg_pt_gp_lock);
1824         __target_attach_tg_pt_gp(lun, tg_pt_gp);
1825         spin_unlock(&lun->lun_tg_pt_gp_lock);
1826 }
1827
1828 static void __target_detach_tg_pt_gp(struct se_lun *lun,
1829                 struct t10_alua_tg_pt_gp *tg_pt_gp)
1830 {
1831         assert_spin_locked(&lun->lun_tg_pt_gp_lock);
1832
1833         spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1834         list_del_init(&lun->lun_tg_pt_gp_link);
1835         tg_pt_gp->tg_pt_gp_members--;
1836         spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1837
1838         lun->lun_tg_pt_gp = NULL;
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 = lun->lun_tg_pt_gp;
1847         if (tg_pt_gp)
1848                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1849         spin_unlock(&lun->lun_tg_pt_gp_lock);
1850 }
1851
1852 ssize_t core_alua_show_tg_pt_gp_info(struct se_lun *lun, char *page)
1853 {
1854         struct config_item *tg_pt_ci;
1855         struct t10_alua_tg_pt_gp *tg_pt_gp;
1856         ssize_t len = 0;
1857
1858         spin_lock(&lun->lun_tg_pt_gp_lock);
1859         tg_pt_gp = lun->lun_tg_pt_gp;
1860         if (tg_pt_gp) {
1861                 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1862                 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1863                         " %hu\nTG Port Primary Access State: %s\nTG Port "
1864                         "Primary Access Status: %s\nTG Port Secondary Access"
1865                         " State: %s\nTG Port Secondary Access Status: %s\n",
1866                         config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1867                         core_alua_dump_state(
1868                                 tg_pt_gp->tg_pt_gp_alua_access_state),
1869                         core_alua_dump_status(
1870                                 tg_pt_gp->tg_pt_gp_alua_access_status),
1871                         atomic_read(&lun->lun_tg_pt_secondary_offline) ?
1872                         "Offline" : "None",
1873                         core_alua_dump_status(lun->lun_tg_pt_secondary_stat));
1874         }
1875         spin_unlock(&lun->lun_tg_pt_gp_lock);
1876
1877         return len;
1878 }
1879
1880 ssize_t core_alua_store_tg_pt_gp_info(
1881         struct se_lun *lun,
1882         const char *page,
1883         size_t count)
1884 {
1885         struct se_portal_group *tpg = lun->lun_tpg;
1886         /*
1887          * rcu_dereference_raw protected by se_lun->lun_group symlink
1888          * reference to se_device->dev_group.
1889          */
1890         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
1891         struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1892         unsigned char buf[TG_PT_GROUP_NAME_BUF];
1893         int move = 0;
1894
1895         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
1896             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
1897                 return -ENODEV;
1898
1899         if (count > TG_PT_GROUP_NAME_BUF) {
1900                 pr_err("ALUA Target Port Group alias too large!\n");
1901                 return -EINVAL;
1902         }
1903         memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1904         memcpy(buf, page, count);
1905         /*
1906          * Any ALUA target port group alias besides "NULL" means we will be
1907          * making a new group association.
1908          */
1909         if (strcmp(strstrip(buf), "NULL")) {
1910                 /*
1911                  * core_alua_get_tg_pt_gp_by_name() will increment reference to
1912                  * struct t10_alua_tg_pt_gp.  This reference is released with
1913                  * core_alua_put_tg_pt_gp_from_name() below.
1914                  */
1915                 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(dev,
1916                                         strstrip(buf));
1917                 if (!tg_pt_gp_new)
1918                         return -ENODEV;
1919         }
1920
1921         spin_lock(&lun->lun_tg_pt_gp_lock);
1922         tg_pt_gp = lun->lun_tg_pt_gp;
1923         if (tg_pt_gp) {
1924                 /*
1925                  * Clearing an existing tg_pt_gp association, and replacing
1926                  * with the default_tg_pt_gp.
1927                  */
1928                 if (!tg_pt_gp_new) {
1929                         pr_debug("Target_Core_ConfigFS: Moving"
1930                                 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1931                                 " alua/%s, ID: %hu back to"
1932                                 " default_tg_pt_gp\n",
1933                                 tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1934                                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1935                                 config_item_name(&lun->lun_group.cg_item),
1936                                 config_item_name(
1937                                         &tg_pt_gp->tg_pt_gp_group.cg_item),
1938                                 tg_pt_gp->tg_pt_gp_id);
1939
1940                         __target_detach_tg_pt_gp(lun, tg_pt_gp);
1941                         __target_attach_tg_pt_gp(lun,
1942                                         dev->t10_alua.default_tg_pt_gp);
1943                         spin_unlock(&lun->lun_tg_pt_gp_lock);
1944
1945                         return count;
1946                 }
1947                 __target_detach_tg_pt_gp(lun, tg_pt_gp);
1948                 move = 1;
1949         }
1950
1951         __target_attach_tg_pt_gp(lun, tg_pt_gp_new);
1952         spin_unlock(&lun->lun_tg_pt_gp_lock);
1953         pr_debug("Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1954                 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1955                 "Moving" : "Adding", tpg->se_tpg_tfo->tpg_get_wwn(tpg),
1956                 tpg->se_tpg_tfo->tpg_get_tag(tpg),
1957                 config_item_name(&lun->lun_group.cg_item),
1958                 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1959                 tg_pt_gp_new->tg_pt_gp_id);
1960
1961         core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1962         return count;
1963 }
1964
1965 ssize_t core_alua_show_access_type(
1966         struct t10_alua_tg_pt_gp *tg_pt_gp,
1967         char *page)
1968 {
1969         if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA) &&
1970             (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA))
1971                 return sprintf(page, "Implicit and Explicit\n");
1972         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICIT_ALUA)
1973                 return sprintf(page, "Implicit\n");
1974         else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICIT_ALUA)
1975                 return sprintf(page, "Explicit\n");
1976         else
1977                 return sprintf(page, "None\n");
1978 }
1979
1980 ssize_t core_alua_store_access_type(
1981         struct t10_alua_tg_pt_gp *tg_pt_gp,
1982         const char *page,
1983         size_t count)
1984 {
1985         unsigned long tmp;
1986         int ret;
1987
1988         ret = kstrtoul(page, 0, &tmp);
1989         if (ret < 0) {
1990                 pr_err("Unable to extract alua_access_type\n");
1991                 return ret;
1992         }
1993         if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
1994                 pr_err("Illegal value for alua_access_type:"
1995                                 " %lu\n", tmp);
1996                 return -EINVAL;
1997         }
1998         if (tmp == 3)
1999                 tg_pt_gp->tg_pt_gp_alua_access_type =
2000                         TPGS_IMPLICIT_ALUA | TPGS_EXPLICIT_ALUA;
2001         else if (tmp == 2)
2002                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICIT_ALUA;
2003         else if (tmp == 1)
2004                 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICIT_ALUA;
2005         else
2006                 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
2007
2008         return count;
2009 }
2010
2011 ssize_t core_alua_show_nonop_delay_msecs(
2012         struct t10_alua_tg_pt_gp *tg_pt_gp,
2013         char *page)
2014 {
2015         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
2016 }
2017
2018 ssize_t core_alua_store_nonop_delay_msecs(
2019         struct t10_alua_tg_pt_gp *tg_pt_gp,
2020         const char *page,
2021         size_t count)
2022 {
2023         unsigned long tmp;
2024         int ret;
2025
2026         ret = kstrtoul(page, 0, &tmp);
2027         if (ret < 0) {
2028                 pr_err("Unable to extract nonop_delay_msecs\n");
2029                 return ret;
2030         }
2031         if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
2032                 pr_err("Passed nonop_delay_msecs: %lu, exceeds"
2033                         " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
2034                         ALUA_MAX_NONOP_DELAY_MSECS);
2035                 return -EINVAL;
2036         }
2037         tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
2038
2039         return count;
2040 }
2041
2042 ssize_t core_alua_show_trans_delay_msecs(
2043         struct t10_alua_tg_pt_gp *tg_pt_gp,
2044         char *page)
2045 {
2046         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
2047 }
2048
2049 ssize_t core_alua_store_trans_delay_msecs(
2050         struct t10_alua_tg_pt_gp *tg_pt_gp,
2051         const char *page,
2052         size_t count)
2053 {
2054         unsigned long tmp;
2055         int ret;
2056
2057         ret = kstrtoul(page, 0, &tmp);
2058         if (ret < 0) {
2059                 pr_err("Unable to extract trans_delay_msecs\n");
2060                 return ret;
2061         }
2062         if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
2063                 pr_err("Passed trans_delay_msecs: %lu, exceeds"
2064                         " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
2065                         ALUA_MAX_TRANS_DELAY_MSECS);
2066                 return -EINVAL;
2067         }
2068         tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
2069
2070         return count;
2071 }
2072
2073 ssize_t core_alua_show_implicit_trans_secs(
2074         struct t10_alua_tg_pt_gp *tg_pt_gp,
2075         char *page)
2076 {
2077         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_implicit_trans_secs);
2078 }
2079
2080 ssize_t core_alua_store_implicit_trans_secs(
2081         struct t10_alua_tg_pt_gp *tg_pt_gp,
2082         const char *page,
2083         size_t count)
2084 {
2085         unsigned long tmp;
2086         int ret;
2087
2088         ret = kstrtoul(page, 0, &tmp);
2089         if (ret < 0) {
2090                 pr_err("Unable to extract implicit_trans_secs\n");
2091                 return ret;
2092         }
2093         if (tmp > ALUA_MAX_IMPLICIT_TRANS_SECS) {
2094                 pr_err("Passed implicit_trans_secs: %lu, exceeds"
2095                         " ALUA_MAX_IMPLICIT_TRANS_SECS: %d\n", tmp,
2096                         ALUA_MAX_IMPLICIT_TRANS_SECS);
2097                 return  -EINVAL;
2098         }
2099         tg_pt_gp->tg_pt_gp_implicit_trans_secs = (int)tmp;
2100
2101         return count;
2102 }
2103
2104 ssize_t core_alua_show_preferred_bit(
2105         struct t10_alua_tg_pt_gp *tg_pt_gp,
2106         char *page)
2107 {
2108         return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
2109 }
2110
2111 ssize_t core_alua_store_preferred_bit(
2112         struct t10_alua_tg_pt_gp *tg_pt_gp,
2113         const char *page,
2114         size_t count)
2115 {
2116         unsigned long tmp;
2117         int ret;
2118
2119         ret = kstrtoul(page, 0, &tmp);
2120         if (ret < 0) {
2121                 pr_err("Unable to extract preferred ALUA value\n");
2122                 return ret;
2123         }
2124         if ((tmp != 0) && (tmp != 1)) {
2125                 pr_err("Illegal value for preferred ALUA: %lu\n", tmp);
2126                 return -EINVAL;
2127         }
2128         tg_pt_gp->tg_pt_gp_pref = (int)tmp;
2129
2130         return count;
2131 }
2132
2133 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
2134 {
2135         return sprintf(page, "%d\n",
2136                 atomic_read(&lun->lun_tg_pt_secondary_offline));
2137 }
2138
2139 ssize_t core_alua_store_offline_bit(
2140         struct se_lun *lun,
2141         const char *page,
2142         size_t count)
2143 {
2144         /*
2145          * rcu_dereference_raw protected by se_lun->lun_group symlink
2146          * reference to se_device->dev_group.
2147          */
2148         struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
2149         unsigned long tmp;
2150         int ret;
2151
2152         if (dev->transport_flags & TRANSPORT_FLAG_PASSTHROUGH_ALUA ||
2153             (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
2154                 return -ENODEV;
2155
2156         ret = kstrtoul(page, 0, &tmp);
2157         if (ret < 0) {
2158                 pr_err("Unable to extract alua_tg_pt_offline value\n");
2159                 return ret;
2160         }
2161         if ((tmp != 0) && (tmp != 1)) {
2162                 pr_err("Illegal value for alua_tg_pt_offline: %lu\n",
2163                                 tmp);
2164                 return -EINVAL;
2165         }
2166
2167         ret = core_alua_set_tg_pt_secondary_state(lun, 0, (int)tmp);
2168         if (ret < 0)
2169                 return -EINVAL;
2170
2171         return count;
2172 }
2173
2174 ssize_t core_alua_show_secondary_status(
2175         struct se_lun *lun,
2176         char *page)
2177 {
2178         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_stat);
2179 }
2180
2181 ssize_t core_alua_store_secondary_status(
2182         struct se_lun *lun,
2183         const char *page,
2184         size_t count)
2185 {
2186         unsigned long tmp;
2187         int ret;
2188
2189         ret = kstrtoul(page, 0, &tmp);
2190         if (ret < 0) {
2191                 pr_err("Unable to extract alua_tg_pt_status\n");
2192                 return ret;
2193         }
2194         if ((tmp != ALUA_STATUS_NONE) &&
2195             (tmp != ALUA_STATUS_ALTERED_BY_EXPLICIT_STPG) &&
2196             (tmp != ALUA_STATUS_ALTERED_BY_IMPLICIT_ALUA)) {
2197                 pr_err("Illegal value for alua_tg_pt_status: %lu\n",
2198                                 tmp);
2199                 return -EINVAL;
2200         }
2201         lun->lun_tg_pt_secondary_stat = (int)tmp;
2202
2203         return count;
2204 }
2205
2206 ssize_t core_alua_show_secondary_write_metadata(
2207         struct se_lun *lun,
2208         char *page)
2209 {
2210         return sprintf(page, "%d\n", lun->lun_tg_pt_secondary_write_md);
2211 }
2212
2213 ssize_t core_alua_store_secondary_write_metadata(
2214         struct se_lun *lun,
2215         const char *page,
2216         size_t count)
2217 {
2218         unsigned long tmp;
2219         int ret;
2220
2221         ret = kstrtoul(page, 0, &tmp);
2222         if (ret < 0) {
2223                 pr_err("Unable to extract alua_tg_pt_write_md\n");
2224                 return ret;
2225         }
2226         if ((tmp != 0) && (tmp != 1)) {
2227                 pr_err("Illegal value for alua_tg_pt_write_md:"
2228                                 " %lu\n", tmp);
2229                 return -EINVAL;
2230         }
2231         lun->lun_tg_pt_secondary_write_md = (int)tmp;
2232
2233         return count;
2234 }
2235
2236 int core_setup_alua(struct se_device *dev)
2237 {
2238         if (!(dev->transport_flags &
2239              TRANSPORT_FLAG_PASSTHROUGH_ALUA) &&
2240             !(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE)) {
2241                 struct t10_alua_lu_gp_member *lu_gp_mem;
2242
2243                 /*
2244                  * Associate this struct se_device with the default ALUA
2245                  * LUN Group.
2246                  */
2247                 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
2248                 if (IS_ERR(lu_gp_mem))
2249                         return PTR_ERR(lu_gp_mem);
2250
2251                 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
2252                 __core_alua_attach_lu_gp_mem(lu_gp_mem,
2253                                 default_lu_gp);
2254                 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
2255
2256                 pr_debug("%s: Adding to default ALUA LU Group:"
2257                         " core/alua/lu_gps/default_lu_gp\n",
2258                         dev->transport->name);
2259         }
2260
2261         return 0;
2262 }