forked from rockchip-linux/kernel
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathtarget_core_alua.c
2019 lines (1816 loc) · 54.7 KB
/
target_core_alua.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*******************************************************************************
* Filename: target_core_alua.c
*
* This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
*
* Copyright (c) 2009-2010 Rising Tide Systems
* Copyright (c) 2009-2010 Linux-iSCSI.org
*
* Nicholas A. Bellinger <nab@kernel.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
******************************************************************************/
#include <linux/version.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/configfs.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <target/target_core_base.h>
#include <target/target_core_device.h>
#include <target/target_core_transport.h>
#include <target/target_core_fabric_ops.h>
#include <target/target_core_configfs.h>
#include "target_core_alua.h"
#include "target_core_hba.h"
#include "target_core_ua.h"
static int core_alua_check_transition(int state, int *primary);
static int core_alua_set_tg_pt_secondary_state(
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
struct se_port *port, int explict, int offline);
static u16 alua_lu_gps_counter;
static u32 alua_lu_gps_count;
static DEFINE_SPINLOCK(lu_gps_lock);
static LIST_HEAD(lu_gps_list);
struct t10_alua_lu_gp *default_lu_gp;
/*
* REPORT_TARGET_PORT_GROUPS
*
* See spc4r17 section 6.27
*/
int core_emulate_report_target_port_groups(struct se_cmd *cmd)
{
struct se_subsystem_dev *su_dev = cmd->se_dev->se_sub_dev;
struct se_port *port;
struct t10_alua_tg_pt_gp *tg_pt_gp;
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
unsigned char *buf;
u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
Target port group descriptor */
buf = transport_kmap_first_data_page(cmd);
spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
list_for_each_entry(tg_pt_gp, &su_dev->t10_alua.tg_pt_gps_list,
tg_pt_gp_list) {
/*
* PREF: Preferred target port bit, determine if this
* bit should be set for port group.
*/
if (tg_pt_gp->tg_pt_gp_pref)
buf[off] = 0x80;
/*
* Set the ASYMMETRIC ACCESS State
*/
buf[off++] |= (atomic_read(
&tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
/*
* Set supported ASYMMETRIC ACCESS State bits
*/
buf[off] = 0x80; /* T_SUP */
buf[off] |= 0x40; /* O_SUP */
buf[off] |= 0x8; /* U_SUP */
buf[off] |= 0x4; /* S_SUP */
buf[off] |= 0x2; /* AN_SUP */
buf[off++] |= 0x1; /* AO_SUP */
/*
* TARGET PORT GROUP
*/
buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
off++; /* Skip over Reserved */
/*
* STATUS CODE
*/
buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
/*
* Vendor Specific field
*/
buf[off++] = 0x00;
/*
* TARGET PORT COUNT
*/
buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
rd_len += 8;
spin_lock(&tg_pt_gp->tg_pt_gp_lock);
list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
tg_pt_gp_mem_list) {
port = tg_pt_gp_mem->tg_pt;
/*
* Start Target Port descriptor format
*
* See spc4r17 section 6.2.7 Table 247
*/
off += 2; /* Skip over Obsolete */
/*
* Set RELATIVE TARGET PORT IDENTIFIER
*/
buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
buf[off++] = (port->sep_rtpi & 0xff);
rd_len += 4;
}
spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
}
spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
/*
* Set the RETURN DATA LENGTH set in the header of the DataIN Payload
*/
buf[0] = ((rd_len >> 24) & 0xff);
buf[1] = ((rd_len >> 16) & 0xff);
buf[2] = ((rd_len >> 8) & 0xff);
buf[3] = (rd_len & 0xff);
transport_kunmap_first_data_page(cmd);
return 0;
}
/*
* SET_TARGET_PORT_GROUPS for explict ALUA operation.
*
* See spc4r17 section 6.35
*/
int core_emulate_set_target_port_groups(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
struct se_subsystem_dev *su_dev = dev->se_sub_dev;
struct se_port *port, *l_port = cmd->se_lun->lun_sep;
struct se_node_acl *nacl = cmd->se_sess->se_node_acl;
struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
unsigned char *buf;
unsigned char *ptr;
u32 len = 4; /* Skip over RESERVED area in header */
int alua_access_state, primary = 0, rc;
u16 tg_pt_id, rtpi;
if (!l_port)
return PYX_TRANSPORT_LU_COMM_FAILURE;
buf = transport_kmap_first_data_page(cmd);
/*
* Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
* for the local tg_pt_gp.
*/
l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
if (!l_tg_pt_gp_mem) {
pr_err("Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
goto out;
}
spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
if (!l_tg_pt_gp) {
spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
pr_err("Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
goto out;
}
rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
if (!rc) {
pr_debug("Unable to process SET_TARGET_PORT_GROUPS"
" while TPGS_EXPLICT_ALUA is disabled\n");
rc = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
goto out;
}
ptr = &buf[4]; /* Skip over RESERVED area in header */
while (len < cmd->data_length) {
alua_access_state = (ptr[0] & 0x0f);
/*
* Check the received ALUA access state, and determine if
* the state is a primary or secondary target port asymmetric
* access state.
*/
rc = core_alua_check_transition(alua_access_state, &primary);
if (rc != 0) {
/*
* If the SET TARGET PORT GROUPS attempts to establish
* an invalid combination of target port asymmetric
* access states or attempts to establish an
* unsupported target port asymmetric access state,
* then the command shall be terminated with CHECK
* CONDITION status, with the sense key set to ILLEGAL
* REQUEST, and the additional sense code set to INVALID
* FIELD IN PARAMETER LIST.
*/
rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
goto out;
}
rc = -1;
/*
* If the ASYMMETRIC ACCESS STATE field (see table 267)
* specifies a primary target port asymmetric access state,
* then the TARGET PORT GROUP OR TARGET PORT field specifies
* a primary target port group for which the primary target
* port asymmetric access state shall be changed. If the
* ASYMMETRIC ACCESS STATE field specifies a secondary target
* port asymmetric access state, then the TARGET PORT GROUP OR
* TARGET PORT field specifies the relative target port
* identifier (see 3.1.120) of the target port for which the
* secondary target port asymmetric access state shall be
* changed.
*/
if (primary) {
tg_pt_id = ((ptr[2] << 8) & 0xff);
tg_pt_id |= (ptr[3] & 0xff);
/*
* Locate the matching target port group ID from
* the global tg_pt_gp list
*/
spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
list_for_each_entry(tg_pt_gp,
&su_dev->t10_alua.tg_pt_gps_list,
tg_pt_gp_list) {
if (!tg_pt_gp->tg_pt_gp_valid_id)
continue;
if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
continue;
atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
smp_mb__after_atomic_inc();
spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
rc = core_alua_do_port_transition(tg_pt_gp,
dev, l_port, nacl,
alua_access_state, 1);
spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
smp_mb__after_atomic_dec();
break;
}
spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
/*
* If not matching target port group ID can be located
* throw an exception with ASCQ: INVALID_PARAMETER_LIST
*/
if (rc != 0) {
rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
goto out;
}
} else {
/*
* Extact the RELATIVE TARGET PORT IDENTIFIER to identify
* the Target Port in question for the the incoming
* SET_TARGET_PORT_GROUPS op.
*/
rtpi = ((ptr[2] << 8) & 0xff);
rtpi |= (ptr[3] & 0xff);
/*
* Locate the matching relative target port identifer
* for the struct se_device storage object.
*/
spin_lock(&dev->se_port_lock);
list_for_each_entry(port, &dev->dev_sep_list,
sep_list) {
if (port->sep_rtpi != rtpi)
continue;
tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
spin_unlock(&dev->se_port_lock);
rc = core_alua_set_tg_pt_secondary_state(
tg_pt_gp_mem, port, 1, 1);
spin_lock(&dev->se_port_lock);
break;
}
spin_unlock(&dev->se_port_lock);
/*
* If not matching relative target port identifier can
* be located, throw an exception with ASCQ:
* INVALID_PARAMETER_LIST
*/
if (rc != 0) {
rc = PYX_TRANSPORT_INVALID_PARAMETER_LIST;
goto out;
}
}
ptr += 4;
len += 4;
}
out:
transport_kunmap_first_data_page(cmd);
return 0;
}
static inline int core_alua_state_nonoptimized(
struct se_cmd *cmd,
unsigned char *cdb,
int nonop_delay_msecs,
u8 *alua_ascq)
{
/*
* Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
* later to determine if processing of this cmd needs to be
* temporarily delayed for the Active/NonOptimized primary access state.
*/
cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
cmd->alua_nonop_delay = nonop_delay_msecs;
return 0;
}
static inline int core_alua_state_standby(
struct se_cmd *cmd,
unsigned char *cdb,
u8 *alua_ascq)
{
/*
* Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
* spc4r17 section 5.9.2.4.4
*/
switch (cdb[0]) {
case INQUIRY:
case LOG_SELECT:
case LOG_SENSE:
case MODE_SELECT:
case MODE_SENSE:
case REPORT_LUNS:
case RECEIVE_DIAGNOSTIC:
case SEND_DIAGNOSTIC:
case MAINTENANCE_IN:
switch (cdb[1]) {
case MI_REPORT_TARGET_PGS:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
return 1;
}
case MAINTENANCE_OUT:
switch (cdb[1]) {
case MO_SET_TARGET_PGS:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
return 1;
}
case REQUEST_SENSE:
case PERSISTENT_RESERVE_IN:
case PERSISTENT_RESERVE_OUT:
case READ_BUFFER:
case WRITE_BUFFER:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
return 1;
}
return 0;
}
static inline int core_alua_state_unavailable(
struct se_cmd *cmd,
unsigned char *cdb,
u8 *alua_ascq)
{
/*
* Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
* spc4r17 section 5.9.2.4.5
*/
switch (cdb[0]) {
case INQUIRY:
case REPORT_LUNS:
case MAINTENANCE_IN:
switch (cdb[1]) {
case MI_REPORT_TARGET_PGS:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
return 1;
}
case MAINTENANCE_OUT:
switch (cdb[1]) {
case MO_SET_TARGET_PGS:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
return 1;
}
case REQUEST_SENSE:
case READ_BUFFER:
case WRITE_BUFFER:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
return 1;
}
return 0;
}
static inline int core_alua_state_transition(
struct se_cmd *cmd,
unsigned char *cdb,
u8 *alua_ascq)
{
/*
* Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
* spc4r17 section 5.9.2.5
*/
switch (cdb[0]) {
case INQUIRY:
case REPORT_LUNS:
case MAINTENANCE_IN:
switch (cdb[1]) {
case MI_REPORT_TARGET_PGS:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
return 1;
}
case REQUEST_SENSE:
case READ_BUFFER:
case WRITE_BUFFER:
return 0;
default:
*alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
return 1;
}
return 0;
}
/*
* Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
* in transport_cmd_sequencer(). This function is assigned to
* struct t10_alua *->state_check() in core_setup_alua()
*/
static int core_alua_state_check_nop(
struct se_cmd *cmd,
unsigned char *cdb,
u8 *alua_ascq)
{
return 0;
}
/*
* Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
* This function is assigned to struct t10_alua *->state_check() in
* core_setup_alua()
*
* Also, this function can return three different return codes to
* signal transport_generic_cmd_sequencer()
*
* return 1: Is used to signal LUN not accecsable, and check condition/not ready
* return 0: Used to signal success
* reutrn -1: Used to signal failure, and invalid cdb field
*/
static int core_alua_state_check(
struct se_cmd *cmd,
unsigned char *cdb,
u8 *alua_ascq)
{
struct se_lun *lun = cmd->se_lun;
struct se_port *port = lun->lun_sep;
struct t10_alua_tg_pt_gp *tg_pt_gp;
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
int out_alua_state, nonop_delay_msecs;
if (!port)
return 0;
/*
* First, check for a struct se_port specific secondary ALUA target port
* access state: OFFLINE
*/
if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
*alua_ascq = ASCQ_04H_ALUA_OFFLINE;
pr_debug("ALUA: Got secondary offline status for local"
" target port\n");
*alua_ascq = ASCQ_04H_ALUA_OFFLINE;
return 1;
}
/*
* Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
* ALUA target port group, to obtain current ALUA access state.
* Otherwise look for the underlying struct se_device association with
* a ALUA logical unit group.
*/
tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
/*
* Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a separate conditional
* statement so the compiler knows explicitly to check this case first.
* For the Optimized ALUA access state case, we want to process the
* incoming fabric cmd ASAP..
*/
if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
return 0;
switch (out_alua_state) {
case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
return core_alua_state_nonoptimized(cmd, cdb,
nonop_delay_msecs, alua_ascq);
case ALUA_ACCESS_STATE_STANDBY:
return core_alua_state_standby(cmd, cdb, alua_ascq);
case ALUA_ACCESS_STATE_UNAVAILABLE:
return core_alua_state_unavailable(cmd, cdb, alua_ascq);
case ALUA_ACCESS_STATE_TRANSITION:
return core_alua_state_transition(cmd, cdb, alua_ascq);
/*
* OFFLINE is a secondary ALUA target port group access state, that is
* handled above with struct se_port->sep_tg_pt_secondary_offline=1
*/
case ALUA_ACCESS_STATE_OFFLINE:
default:
pr_err("Unknown ALUA access state: 0x%02x\n",
out_alua_state);
return -EINVAL;
}
return 0;
}
/*
* Check implict and explict ALUA state change request.
*/
static int core_alua_check_transition(int state, int *primary)
{
switch (state) {
case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
case ALUA_ACCESS_STATE_STANDBY:
case ALUA_ACCESS_STATE_UNAVAILABLE:
/*
* OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
* defined as primary target port asymmetric access states.
*/
*primary = 1;
break;
case ALUA_ACCESS_STATE_OFFLINE:
/*
* OFFLINE state is defined as a secondary target port
* asymmetric access state.
*/
*primary = 0;
break;
default:
pr_err("Unknown ALUA access state: 0x%02x\n", state);
return -EINVAL;
}
return 0;
}
static char *core_alua_dump_state(int state)
{
switch (state) {
case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
return "Active/Optimized";
case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
return "Active/NonOptimized";
case ALUA_ACCESS_STATE_STANDBY:
return "Standby";
case ALUA_ACCESS_STATE_UNAVAILABLE:
return "Unavailable";
case ALUA_ACCESS_STATE_OFFLINE:
return "Offline";
default:
return "Unknown";
}
return NULL;
}
char *core_alua_dump_status(int status)
{
switch (status) {
case ALUA_STATUS_NONE:
return "None";
case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
return "Altered by Explict STPG";
case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
return "Altered by Implict ALUA";
default:
return "Unknown";
}
return NULL;
}
/*
* Used by fabric modules to determine when we need to delay processing
* for the Active/NonOptimized paths..
*/
int core_alua_check_nonop_delay(
struct se_cmd *cmd)
{
if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
return 0;
if (in_interrupt())
return 0;
/*
* The ALUA Active/NonOptimized access state delay can be disabled
* in via configfs with a value of zero
*/
if (!cmd->alua_nonop_delay)
return 0;
/*
* struct se_cmd->alua_nonop_delay gets set by a target port group
* defined interval in core_alua_state_nonoptimized()
*/
msleep_interruptible(cmd->alua_nonop_delay);
return 0;
}
EXPORT_SYMBOL(core_alua_check_nonop_delay);
/*
* Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
*
*/
static int core_alua_write_tpg_metadata(
const char *path,
unsigned char *md_buf,
u32 md_buf_len)
{
mm_segment_t old_fs;
struct file *file;
struct iovec iov[1];
int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
memset(iov, 0, sizeof(struct iovec));
file = filp_open(path, flags, 0600);
if (IS_ERR(file) || !file || !file->f_dentry) {
pr_err("filp_open(%s) for ALUA metadata failed\n",
path);
return -ENODEV;
}
iov[0].iov_base = &md_buf[0];
iov[0].iov_len = md_buf_len;
old_fs = get_fs();
set_fs(get_ds());
ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
set_fs(old_fs);
if (ret < 0) {
pr_err("Error writing ALUA metadata file: %s\n", path);
filp_close(file, NULL);
return -EIO;
}
filp_close(file, NULL);
return 0;
}
/*
* Called with tg_pt_gp->tg_pt_gp_md_mutex held
*/
static int core_alua_update_tpg_primary_metadata(
struct t10_alua_tg_pt_gp *tg_pt_gp,
int primary_state,
unsigned char *md_buf)
{
struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
struct t10_wwn *wwn = &su_dev->t10_wwn;
char path[ALUA_METADATA_PATH_LEN];
int len;
memset(path, 0, ALUA_METADATA_PATH_LEN);
len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
"tg_pt_gp_id=%hu\n"
"alua_access_state=0x%02x\n"
"alua_access_status=0x%02x\n",
tg_pt_gp->tg_pt_gp_id, primary_state,
tg_pt_gp->tg_pt_gp_alua_access_status);
snprintf(path, ALUA_METADATA_PATH_LEN,
"/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
return core_alua_write_tpg_metadata(path, md_buf, len);
}
static int core_alua_do_transition_tg_pt(
struct t10_alua_tg_pt_gp *tg_pt_gp,
struct se_port *l_port,
struct se_node_acl *nacl,
unsigned char *md_buf,
int new_state,
int explict)
{
struct se_dev_entry *se_deve;
struct se_lun_acl *lacl;
struct se_port *port;
struct t10_alua_tg_pt_gp_member *mem;
int old_state = 0;
/*
* Save the old primary ALUA access state, and set the current state
* to ALUA_ACCESS_STATE_TRANSITION.
*/
old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
ALUA_ACCESS_STATE_TRANSITION);
tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
/*
* Check for the optional ALUA primary state transition delay
*/
if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
spin_lock(&tg_pt_gp->tg_pt_gp_lock);
list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
tg_pt_gp_mem_list) {
port = mem->tg_pt;
/*
* After an implicit target port asymmetric access state
* change, a device server shall establish a unit attention
* condition for the initiator port associated with every I_T
* nexus with the additional sense code set to ASYMMETRIC
* ACCESS STATE CHAGED.
*
* After an explicit target port asymmetric access state
* change, a device server shall establish a unit attention
* condition with the additional sense code set to ASYMMETRIC
* ACCESS STATE CHANGED for the initiator port associated with
* every I_T nexus other than the I_T nexus on which the SET
* TARGET PORT GROUPS command
*/
atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
smp_mb__after_atomic_inc();
spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
spin_lock_bh(&port->sep_alua_lock);
list_for_each_entry(se_deve, &port->sep_alua_list,
alua_port_list) {
lacl = se_deve->se_lun_acl;
/*
* se_deve->se_lun_acl pointer may be NULL for a
* entry created without explict Node+MappedLUN ACLs
*/
if (!lacl)
continue;
if (explict &&
(nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
(l_port != NULL) && (l_port == port))
continue;
core_scsi3_ua_allocate(lacl->se_lun_nacl,
se_deve->mapped_lun, 0x2A,
ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
}
spin_unlock_bh(&port->sep_alua_lock);
spin_lock(&tg_pt_gp->tg_pt_gp_lock);
atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
smp_mb__after_atomic_dec();
}
spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
/*
* Update the ALUA metadata buf that has been allocated in
* core_alua_do_port_transition(), this metadata will be written
* to struct file.
*
* Note that there is the case where we do not want to update the
* metadata when the saved metadata is being parsed in userspace
* when setting the existing port access state and access status.
*
* Also note that the failure to write out the ALUA metadata to
* struct file does NOT affect the actual ALUA transition.
*/
if (tg_pt_gp->tg_pt_gp_write_metadata) {
mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
core_alua_update_tpg_primary_metadata(tg_pt_gp,
new_state, md_buf);
mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
}
/*
* Set the current primary ALUA access state to the requested new state
*/
atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
pr_debug("Successful %s ALUA transition TG PT Group: %s ID: %hu"
" from primary access state %s to %s\n", (explict) ? "explict" :
"implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
core_alua_dump_state(new_state));
return 0;
}
int core_alua_do_port_transition(
struct t10_alua_tg_pt_gp *l_tg_pt_gp,
struct se_device *l_dev,
struct se_port *l_port,
struct se_node_acl *l_nacl,
int new_state,
int explict)
{
struct se_device *dev;
struct se_port *port;
struct se_subsystem_dev *su_dev;
struct se_node_acl *nacl;
struct t10_alua_lu_gp *lu_gp;
struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
struct t10_alua_tg_pt_gp *tg_pt_gp;
unsigned char *md_buf;
int primary;
if (core_alua_check_transition(new_state, &primary) != 0)
return -EINVAL;
md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
if (!md_buf) {
pr_err("Unable to allocate buf for ALUA metadata\n");
return -ENOMEM;
}
local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
lu_gp = local_lu_gp_mem->lu_gp;
atomic_inc(&lu_gp->lu_gp_ref_cnt);
smp_mb__after_atomic_inc();
spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
/*
* For storage objects that are members of the 'default_lu_gp',
* we only do transition on the passed *l_tp_pt_gp, and not
* on all of the matching target port groups IDs in default_lu_gp.
*/
if (!lu_gp->lu_gp_id) {
/*
* core_alua_do_transition_tg_pt() will always return
* success.
*/
core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
md_buf, new_state, explict);
atomic_dec(&lu_gp->lu_gp_ref_cnt);
smp_mb__after_atomic_dec();
kfree(md_buf);
return 0;
}
/*
* For all other LU groups aside from 'default_lu_gp', walk all of
* the associated storage objects looking for a matching target port
* group ID from the local target port group.
*/
spin_lock(&lu_gp->lu_gp_lock);
list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
lu_gp_mem_list) {
dev = lu_gp_mem->lu_gp_mem_dev;
su_dev = dev->se_sub_dev;
atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
smp_mb__after_atomic_inc();
spin_unlock(&lu_gp->lu_gp_lock);
spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
list_for_each_entry(tg_pt_gp,
&su_dev->t10_alua.tg_pt_gps_list,
tg_pt_gp_list) {
if (!tg_pt_gp->tg_pt_gp_valid_id)
continue;
/*
* If the target behavior port asymmetric access state
* is changed for any target port group accessiable via
* a logical unit within a LU group, the target port
* behavior group asymmetric access states for the same
* target port group accessible via other logical units
* in that LU group will also change.
*/
if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
continue;
if (l_tg_pt_gp == tg_pt_gp) {
port = l_port;
nacl = l_nacl;
} else {
port = NULL;
nacl = NULL;
}
atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
smp_mb__after_atomic_inc();
spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
/*
* core_alua_do_transition_tg_pt() will always return
* success.
*/
core_alua_do_transition_tg_pt(tg_pt_gp, port,
nacl, md_buf, new_state, explict);
spin_lock(&su_dev->t10_alua.tg_pt_gps_lock);
atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
smp_mb__after_atomic_dec();
}
spin_unlock(&su_dev->t10_alua.tg_pt_gps_lock);
spin_lock(&lu_gp->lu_gp_lock);
atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
smp_mb__after_atomic_dec();
}
spin_unlock(&lu_gp->lu_gp_lock);
pr_debug("Successfully processed LU Group: %s all ALUA TG PT"
" Group IDs: %hu %s transition to primary state: %s\n",
config_item_name(&lu_gp->lu_gp_group.cg_item),
l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
core_alua_dump_state(new_state));
atomic_dec(&lu_gp->lu_gp_ref_cnt);
smp_mb__after_atomic_dec();
kfree(md_buf);
return 0;
}
/*
* Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
*/
static int core_alua_update_tpg_secondary_metadata(
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
struct se_port *port,
unsigned char *md_buf,
u32 md_buf_len)
{
struct se_portal_group *se_tpg = port->sep_tpg;
char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
int len;
memset(path, 0, ALUA_METADATA_PATH_LEN);
memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
se_tpg->se_tpg_tfo->tpg_get_wwn(se_tpg));
if (se_tpg->se_tpg_tfo->tpg_get_tag != NULL)
snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
se_tpg->se_tpg_tfo->tpg_get_tag(se_tpg));
len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
"alua_tg_pt_status=0x%02x\n",
atomic_read(&port->sep_tg_pt_secondary_offline),
port->sep_tg_pt_secondary_stat);
snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
se_tpg->se_tpg_tfo->get_fabric_name(), wwn,
port->sep_lun->unpacked_lun);
return core_alua_write_tpg_metadata(path, md_buf, len);
}
static int core_alua_set_tg_pt_secondary_state(
struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
struct se_port *port,
int explict,
int offline)
{
struct t10_alua_tg_pt_gp *tg_pt_gp;
unsigned char *md_buf;
u32 md_buf_len;
int trans_delay_msecs;