aboutsummaryrefslogtreecommitdiff
path: root/drivers/nvdimm/label.c
blob: 082253a3a9560778c4ddaaaebacd4c3a6a8c72d0 (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
 */
#include <linux/device.h>
#include <linux/ndctl.h>
#include <linux/uuid.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/nd.h>
#include "nd-core.h"
#include "label.h"
#include "nd.h"

static guid_t nvdimm_btt_guid;
static guid_t nvdimm_btt2_guid;
static guid_t nvdimm_pfn_guid;
static guid_t nvdimm_dax_guid;

static uuid_t nvdimm_btt_uuid;
static uuid_t nvdimm_btt2_uuid;
static uuid_t nvdimm_pfn_uuid;
static uuid_t nvdimm_dax_uuid;

static uuid_t cxl_region_uuid;
static uuid_t cxl_namespace_uuid;

static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";

static u32 best_seq(u32 a, u32 b)
{
	a &= NSINDEX_SEQ_MASK;
	b &= NSINDEX_SEQ_MASK;

	if (a == 0 || a == b)
		return b;
	else if (b == 0)
		return a;
	else if (nd_inc_seq(a) == b)
		return b;
	else
		return a;
}

unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
{
	return ndd->nslabel_size;
}

static size_t __sizeof_namespace_index(u32 nslot)
{
	return ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
			NSINDEX_ALIGN);
}

static int __nvdimm_num_label_slots(struct nvdimm_drvdata *ndd,
		size_t index_size)
{
	return (ndd->nsarea.config_size - index_size * 2) /
			sizeof_namespace_label(ndd);
}

int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
{
	u32 tmp_nslot, n;

	tmp_nslot = ndd->nsarea.config_size / sizeof_namespace_label(ndd);
	n = __sizeof_namespace_index(tmp_nslot) / NSINDEX_ALIGN;

	return __nvdimm_num_label_slots(ndd, NSINDEX_ALIGN * n);
}

size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
{
	u32 nslot, space, size;

	/*
	 * Per UEFI 2.7, the minimum size of the Label Storage Area is large
	 * enough to hold 2 index blocks and 2 labels.  The minimum index
	 * block size is 256 bytes. The label size is 128 for namespaces
	 * prior to version 1.2 and at minimum 256 for version 1.2 and later.
	 */
	nslot = nvdimm_num_label_slots(ndd);
	space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
	size = __sizeof_namespace_index(nslot) * 2;
	if (size <= space && nslot >= 2)
		return size / 2;

	dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
			ndd->nsarea.config_size, sizeof_namespace_label(ndd));
	return 0;
}

static int __nd_label_validate(struct nvdimm_drvdata *ndd)
{
	/*
	 * On media label format consists of two index blocks followed
	 * by an array of labels.  None of these structures are ever
	 * updated in place.  A sequence number tracks the current
	 * active index and the next one to write, while labels are
	 * written to free slots.
	 *
	 *     +------------+
	 *     |            |
	 *     |  nsindex0  |
	 *     |            |
	 *     +------------+
	 *     |            |
	 *     |  nsindex1  |
	 *     |            |
	 *     +------------+
	 *     |   label0   |
	 *     +------------+
	 *     |   label1   |
	 *     +------------+
	 *     |            |
	 *      ....nslot...
	 *     |            |
	 *     +------------+
	 *     |   labelN   |
	 *     +------------+
	 */
	struct nd_namespace_index *nsindex[] = {
		to_namespace_index(ndd, 0),
		to_namespace_index(ndd, 1),
	};
	const int num_index = ARRAY_SIZE(nsindex);
	struct device *dev = ndd->dev;
	bool valid[2] = { 0 };
	int i, num_valid = 0;
	u32 seq;

	for (i = 0; i < num_index; i++) {
		u32 nslot;
		u8 sig[NSINDEX_SIG_LEN];
		u64 sum_save, sum, size;
		unsigned int version, labelsize;

		memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
		if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
			dev_dbg(dev, "nsindex%d signature invalid\n", i);
			continue;
		}

		/* label sizes larger than 128 arrived with v1.2 */
		version = __le16_to_cpu(nsindex[i]->major) * 100
			+ __le16_to_cpu(nsindex[i]->minor);
		if (version >= 102)
			labelsize = 1 << (7 + nsindex[i]->labelsize);
		else
			labelsize = 128;

		if (labelsize != sizeof_namespace_label(ndd)) {
			dev_dbg(dev, "nsindex%d labelsize %d invalid\n",
					i, nsindex[i]->labelsize);
			continue;
		}

		sum_save = __le64_to_cpu(nsindex[i]->checksum);
		nsindex[i]->checksum = __cpu_to_le64(0);
		sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
		nsindex[i]->checksum = __cpu_to_le64(sum_save);
		if (sum != sum_save) {
			dev_dbg(dev, "nsindex%d checksum invalid\n", i);
			continue;
		}

		seq = __le32_to_cpu(nsindex[i]->seq);
		if ((seq & NSINDEX_SEQ_MASK) == 0) {
			dev_dbg(dev, "nsindex%d sequence: %#x invalid\n", i, seq);
			continue;
		}

		/* sanity check the index against expected values */
		if (__le64_to_cpu(nsindex[i]->myoff)
				!= i * sizeof_namespace_index(ndd)) {
			dev_dbg(dev, "nsindex%d myoff: %#llx invalid\n",
					i, (unsigned long long)
					__le64_to_cpu(nsindex[i]->myoff));
			continue;
		}
		if (__le64_to_cpu(nsindex[i]->otheroff)
				!= (!i) * sizeof_namespace_index(ndd)) {
			dev_dbg(dev, "nsindex%d otheroff: %#llx invalid\n",
					i, (unsigned long long)
					__le64_to_cpu(nsindex[i]->otheroff));
			continue;
		}
		if (__le64_to_cpu(nsindex[i]->labeloff)
				!= 2 * sizeof_namespace_index(ndd)) {
			dev_dbg(dev, "nsindex%d labeloff: %#llx invalid\n",
					i, (unsigned long long)
					__le64_to_cpu(nsindex[i]->labeloff));
			continue;
		}

		size = __le64_to_cpu(nsindex[i]->mysize);
		if (size > sizeof_namespace_index(ndd)
				|| size < sizeof(struct nd_namespace_index)) {
			dev_dbg(dev, "nsindex%d mysize: %#llx invalid\n", i, size);
			continue;
		}

		nslot = __le32_to_cpu(nsindex[i]->nslot);
		if (nslot * sizeof_namespace_label(ndd)
				+ 2 * sizeof_namespace_index(ndd)
				> ndd->nsarea.config_size) {
			dev_dbg(dev, "nsindex%d nslot: %u invalid, config_size: %#x\n",
					i, nslot, ndd->nsarea.config_size);
			continue;
		}
		valid[i] = true;
		num_valid++;
	}

	switch (num_valid) {
	case 0:
		break;
	case 1:
		for (i = 0; i < num_index; i++)
			if (valid[i])
				return i;
		/* can't have num_valid > 0 but valid[] = { false, false } */
		WARN_ON(1);
		break;
	default:
		/* pick the best index... */
		seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
				__le32_to_cpu(nsindex[1]->seq));
		if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
			return 1;
		else
			return 0;
		break;
	}

	return -1;
}

static int nd_label_validate(struct nvdimm_drvdata *ndd)
{
	/*
	 * In order to probe for and validate namespace index blocks we
	 * need to know the size of the labels, and we can't trust the
	 * size of the labels until we validate the index blocks.
	 * Resolve this dependency loop by probing for known label
	 * sizes, but default to v1.2 256-byte namespace labels if
	 * discovery fails.
	 */
	int label_size[] = { 128, 256 };
	int i, rc;

	for (i = 0; i < ARRAY_SIZE(label_size); i++) {
		ndd->nslabel_size = label_size[i];
		rc = __nd_label_validate(ndd);
		if (rc >= 0)
			return rc;
	}

	return -1;
}

static void nd_label_copy(struct nvdimm_drvdata *ndd,
			  struct nd_namespace_index *dst,
			  struct nd_namespace_index *src)
{
	/* just exit if either destination or source is NULL */
	if (!dst || !src)
		return;

	memcpy(dst, src, sizeof_namespace_index(ndd));
}

static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
{
	void *base = to_namespace_index(ndd, 0);

	return base + 2 * sizeof_namespace_index(ndd);
}

static int to_slot(struct nvdimm_drvdata *ndd,
		struct nd_namespace_label *nd_label)
{
	unsigned long label, base;

	label = (unsigned long) nd_label;
	base = (unsigned long) nd_label_base(ndd);

	return (label - base) / sizeof_namespace_label(ndd);
}

static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
{
	unsigned long label, base;

	base = (unsigned long) nd_label_base(ndd);
	label = base + sizeof_namespace_label(ndd) * slot;

	return (struct nd_namespace_label *) label;
}

#define for_each_clear_bit_le(bit, addr, size) \
	for ((bit) = find_next_zero_bit_le((addr), (size), 0);  \
	     (bit) < (size);                                    \
	     (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))

/**
 * preamble_index - common variable initialization for nd_label_* routines
 * @ndd: dimm container for the relevant label set
 * @idx: namespace_index index
 * @nsindex_out: on return set to the currently active namespace index
 * @free: on return set to the free label bitmap in the index
 * @nslot: on return set to the number of slots in the label space
 */
static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
		struct nd_namespace_index **nsindex_out,
		unsigned long **free, u32 *nslot)
{
	struct nd_namespace_index *nsindex;

	nsindex = to_namespace_index(ndd, idx);
	if (nsindex == NULL)
		return false;

	*free = (unsigned long *) nsindex->free;
	*nslot = __le32_to_cpu(nsindex->nslot);
	*nsindex_out = nsindex;

	return true;
}

char *nd_label_gen_id(struct nd_label_id *label_id, const uuid_t *uuid,
		      u32 flags)
{
	if (!label_id || !uuid)
		return NULL;
	snprintf(label_id->id, ND_LABEL_ID_SIZE, "pmem-%pUb", uuid);
	return label_id->id;
}

static bool preamble_current(struct nvdimm_drvdata *ndd,
		struct nd_namespace_index **nsindex,
		unsigned long **free, u32 *nslot)
{
	return preamble_index(ndd, ndd->ns_current, nsindex,
			free, nslot);
}

static bool preamble_next(struct nvdimm_drvdata *ndd,
		struct nd_namespace_index **nsindex,
		unsigned long **free, u32 *nslot)
{
	return preamble_index(ndd, ndd->ns_next, nsindex,
			free, nslot);
}

static bool nsl_validate_checksum(struct nvdimm_drvdata *ndd,
				  struct nd_namespace_label *nd_label)
{
	u64 sum, sum_save;

	if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
		return true;

	sum_save = nsl_get_checksum(ndd, nd_label);
	nsl_set_checksum(ndd, nd_label, 0);
	sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
	nsl_set_checksum(ndd, nd_label, sum_save);
	return sum == sum_save;
}

static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
				   struct nd_namespace_label *nd_label)
{
	u64 sum;

	if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
		return;
	nsl_set_checksum(ndd, nd_label, 0);
	sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
	nsl_set_checksum(ndd, nd_label, sum);
}

static bool slot_valid(struct nvdimm_drvdata *ndd,
		struct nd_namespace_label *nd_label, u32 slot)
{
	bool valid;

	/* check that we are written where we expect to be written */
	if (slot != nsl_get_slot(ndd, nd_label))
		return false;
	valid = nsl_validate_checksum(ndd, nd_label);
	if (!valid)
		dev_dbg(ndd->dev, "fail checksum. slot: %d\n", slot);
	return valid;
}

int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
{
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	u32 nslot, slot;

	if (!preamble_current(ndd, &nsindex, &free, &nslot))
		return 0; /* no label, nothing to reserve */

	for_each_clear_bit_le(slot, free, nslot) {
		struct nd_namespace_label *nd_label;
		struct nd_region *nd_region = NULL;
		struct nd_label_id label_id;
		struct resource *res;
		uuid_t label_uuid;
		u32 flags;

		nd_label = to_label(ndd, slot);

		if (!slot_valid(ndd, nd_label, slot))
			continue;

		nsl_get_uuid(ndd, nd_label, &label_uuid);
		flags = nsl_get_flags(ndd, nd_label);
		nd_label_gen_id(&label_id, &label_uuid, flags);
		res = nvdimm_allocate_dpa(ndd, &label_id,
					  nsl_get_dpa(ndd, nd_label),
					  nsl_get_rawsize(ndd, nd_label));
		nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
		if (!res)
			return -EBUSY;
	}

	return 0;
}

int nd_label_data_init(struct nvdimm_drvdata *ndd)
{
	size_t config_size, read_size, max_xfer, offset;
	struct nd_namespace_index *nsindex;
	unsigned int i;
	int rc = 0;
	u32 nslot;

	if (ndd->data)
		return 0;

	if (ndd->nsarea.status || ndd->nsarea.max_xfer == 0) {
		dev_dbg(ndd->dev, "failed to init config data area: (%u:%u)\n",
			ndd->nsarea.max_xfer, ndd->nsarea.config_size);
		return -ENXIO;
	}

	/*
	 * We need to determine the maximum index area as this is the section
	 * we must read and validate before we can start processing labels.
	 *
	 * If the area is too small to contain the two indexes and 2 labels
	 * then we abort.
	 *
	 * Start at a label size of 128 as this should result in the largest
	 * possible namespace index size.
	 */
	ndd->nslabel_size = 128;
	read_size = sizeof_namespace_index(ndd) * 2;
	if (!read_size)
		return -ENXIO;

	/* Allocate config data */
	config_size = ndd->nsarea.config_size;
	ndd->data = kvzalloc(config_size, GFP_KERNEL);
	if (!ndd->data)
		return -ENOMEM;

	/*
	 * We want to guarantee as few reads as possible while conserving
	 * memory. To do that we figure out how much unused space will be left
	 * in the last read, divide that by the total number of reads it is
	 * going to take given our maximum transfer size, and then reduce our
	 * maximum transfer size based on that result.
	 */
	max_xfer = min_t(size_t, ndd->nsarea.max_xfer, config_size);
	if (read_size < max_xfer) {
		/* trim waste */
		max_xfer -= ((max_xfer - 1) - (config_size - 1) % max_xfer) /
			    DIV_ROUND_UP(config_size, max_xfer);
		/* make certain we read indexes in exactly 1 read */
		if (max_xfer < read_size)
			max_xfer = read_size;
	}

	/* Make our initial read size a multiple of max_xfer size */
	read_size = min(DIV_ROUND_UP(read_size, max_xfer) * max_xfer,
			config_size);

	/* Read the index data */
	rc = nvdimm_get_config_data(ndd, ndd->data, 0, read_size);
	if (rc)
		goto out_err;

	/* Validate index data, if not valid assume all labels are invalid */
	ndd->ns_current = nd_label_validate(ndd);
	if (ndd->ns_current < 0)
		return 0;

	/* Record our index values */
	ndd->ns_next = nd_label_next_nsindex(ndd->ns_current);

	/* Copy "current" index on top of the "next" index */
	nsindex = to_current_namespace_index(ndd);
	nd_label_copy(ndd, to_next_namespace_index(ndd), nsindex);

	/* Determine starting offset for label data */
	offset = __le64_to_cpu(nsindex->labeloff);
	nslot = __le32_to_cpu(nsindex->nslot);

	/* Loop through the free list pulling in any active labels */
	for (i = 0; i < nslot; i++, offset += ndd->nslabel_size) {
		size_t label_read_size;

		/* zero out the unused labels */
		if (test_bit_le(i, nsindex->free)) {
			memset(ndd->data + offset, 0, ndd->nslabel_size);
			continue;
		}

		/* if we already read past here then just continue */
		if (offset + ndd->nslabel_size <= read_size)
			continue;

		/* if we haven't read in a while reset our read_size offset */
		if (read_size < offset)
			read_size = offset;

		/* determine how much more will be read after this next call. */
		label_read_size = offset + ndd->nslabel_size - read_size;
		label_read_size = DIV_ROUND_UP(label_read_size, max_xfer) *
				  max_xfer;

		/* truncate last read if needed */
		if (read_size + label_read_size > config_size)
			label_read_size = config_size - read_size;

		/* Read the label data */
		rc = nvdimm_get_config_data(ndd, ndd->data + read_size,
					    read_size, label_read_size);
		if (rc)
			goto out_err;

		/* push read_size to next read offset */
		read_size += label_read_size;
	}

	dev_dbg(ndd->dev, "len: %zu rc: %d\n", offset, rc);
out_err:
	return rc;
}

int nd_label_active_count(struct nvdimm_drvdata *ndd)
{
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	u32 nslot, slot;
	int count = 0;

	if (!preamble_current(ndd, &nsindex, &free, &nslot))
		return 0;

	for_each_clear_bit_le(slot, free, nslot) {
		struct nd_namespace_label *nd_label;

		nd_label = to_label(ndd, slot);

		if (!slot_valid(ndd, nd_label, slot)) {
			u32 label_slot = nsl_get_slot(ndd, nd_label);
			u64 size = nsl_get_rawsize(ndd, nd_label);
			u64 dpa = nsl_get_dpa(ndd, nd_label);

			dev_dbg(ndd->dev,
				"slot%d invalid slot: %d dpa: %llx size: %llx\n",
					slot, label_slot, dpa, size);
			continue;
		}
		count++;
	}
	return count;
}

struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
{
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	u32 nslot, slot;

	if (!preamble_current(ndd, &nsindex, &free, &nslot))
		return NULL;

	for_each_clear_bit_le(slot, free, nslot) {
		struct nd_namespace_label *nd_label;

		nd_label = to_label(ndd, slot);
		if (!slot_valid(ndd, nd_label, slot))
			continue;

		if (n-- == 0)
			return to_label(ndd, slot);
	}

	return NULL;
}

u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
{
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	u32 nslot, slot;

	if (!preamble_next(ndd, &nsindex, &free, &nslot))
		return UINT_MAX;

	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));

	slot = find_next_bit_le(free, nslot, 0);
	if (slot == nslot)
		return UINT_MAX;

	clear_bit_le(slot, free);

	return slot;
}

bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
{
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	u32 nslot;

	if (!preamble_next(ndd, &nsindex, &free, &nslot))
		return false;

	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));

	if (slot < nslot)
		return !test_and_set_bit_le(slot, free);
	return false;
}

u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
{
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	u32 nslot;

	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));

	if (!preamble_next(ndd, &nsindex, &free, &nslot))
		return nvdimm_num_label_slots(ndd);

	return bitmap_weight(free, nslot);
}

static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
		unsigned long flags)
{
	struct nd_namespace_index *nsindex;
	unsigned long offset;
	u64 checksum;
	u32 nslot;
	int rc;

	nsindex = to_namespace_index(ndd, index);
	if (flags & ND_NSINDEX_INIT)
		nslot = nvdimm_num_label_slots(ndd);
	else
		nslot = __le32_to_cpu(nsindex->nslot);

	memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
	memset(&nsindex->flags, 0, 3);
	nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
	nsindex->seq = __cpu_to_le32(seq);
	offset = (unsigned long) nsindex
		- (unsigned long) to_namespace_index(ndd, 0);
	nsindex->myoff = __cpu_to_le64(offset);
	nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
	offset = (unsigned long) to_namespace_index(ndd,
			nd_label_next_nsindex(index))
		- (unsigned long) to_namespace_index(ndd, 0);
	nsindex->otheroff = __cpu_to_le64(offset);
	offset = (unsigned long) nd_label_base(ndd)
		- (unsigned long) to_namespace_index(ndd, 0);
	nsindex->labeloff = __cpu_to_le64(offset);
	nsindex->nslot = __cpu_to_le32(nslot);
	nsindex->major = __cpu_to_le16(1);
	if (sizeof_namespace_label(ndd) < 256)
		nsindex->minor = __cpu_to_le16(1);
	else
		nsindex->minor = __cpu_to_le16(2);
	nsindex->checksum = __cpu_to_le64(0);
	if (flags & ND_NSINDEX_INIT) {
		unsigned long *free = (unsigned long *) nsindex->free;
		u32 nfree = ALIGN(nslot, BITS_PER_LONG);
		int last_bits, i;

		memset(nsindex->free, 0xff, nfree / 8);
		for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
			clear_bit_le(nslot + i, free);
	}
	checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
	nsindex->checksum = __cpu_to_le64(checksum);
	rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
			nsindex, sizeof_namespace_index(ndd));
	if (rc < 0)
		return rc;

	if (flags & ND_NSINDEX_INIT)
		return 0;

	/* copy the index we just wrote to the new 'next' */
	WARN_ON(index != ndd->ns_next);
	nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
	ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
	ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
	WARN_ON(ndd->ns_current == ndd->ns_next);

	return 0;
}

static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
		struct nd_namespace_label *nd_label)
{
	return (unsigned long) nd_label
		- (unsigned long) to_namespace_index(ndd, 0);
}

static enum nvdimm_claim_class guid_to_nvdimm_cclass(guid_t *guid)
{
	if (guid_equal(guid, &nvdimm_btt_guid))
		return NVDIMM_CCLASS_BTT;
	else if (guid_equal(guid, &nvdimm_btt2_guid))
		return NVDIMM_CCLASS_BTT2;
	else if (guid_equal(guid, &nvdimm_pfn_guid))
		return NVDIMM_CCLASS_PFN;
	else if (guid_equal(guid, &nvdimm_dax_guid))
		return NVDIMM_CCLASS_DAX;
	else if (guid_equal(guid, &guid_null))
		return NVDIMM_CCLASS_NONE;

	return NVDIMM_CCLASS_UNKNOWN;
}

/* CXL labels store UUIDs instead of GUIDs for the same data */
static enum nvdimm_claim_class uuid_to_nvdimm_cclass(uuid_t *uuid)
{
	if (uuid_equal(uuid, &nvdimm_btt_uuid))
		return NVDIMM_CCLASS_BTT;
	else if (uuid_equal(uuid, &nvdimm_btt2_uuid))
		return NVDIMM_CCLASS_BTT2;
	else if (uuid_equal(uuid, &nvdimm_pfn_uuid))
		return NVDIMM_CCLASS_PFN;
	else if (uuid_equal(uuid, &nvdimm_dax_uuid))
		return NVDIMM_CCLASS_DAX;
	else if (uuid_equal(uuid, &uuid_null))
		return NVDIMM_CCLASS_NONE;

	return NVDIMM_CCLASS_UNKNOWN;
}

static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
	guid_t *target)
{
	if (claim_class == NVDIMM_CCLASS_BTT)
		return &nvdimm_btt_guid;
	else if (claim_class == NVDIMM_CCLASS_BTT2)
		return &nvdimm_btt2_guid;
	else if (claim_class == NVDIMM_CCLASS_PFN)
		return &nvdimm_pfn_guid;
	else if (claim_class == NVDIMM_CCLASS_DAX)
		return &nvdimm_dax_guid;
	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
		/*
		 * If we're modifying a namespace for which we don't
		 * know the claim_class, don't touch the existing guid.
		 */
		return target;
	} else
		return &guid_null;
}

/* CXL labels store UUIDs instead of GUIDs for the same data */
static const uuid_t *to_abstraction_uuid(enum nvdimm_claim_class claim_class,
					 uuid_t *target)
{
	if (claim_class == NVDIMM_CCLASS_BTT)
		return &nvdimm_btt_uuid;
	else if (claim_class == NVDIMM_CCLASS_BTT2)
		return &nvdimm_btt2_uuid;
	else if (claim_class == NVDIMM_CCLASS_PFN)
		return &nvdimm_pfn_uuid;
	else if (claim_class == NVDIMM_CCLASS_DAX)
		return &nvdimm_dax_uuid;
	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
		/*
		 * If we're modifying a namespace for which we don't
		 * know the claim_class, don't touch the existing uuid.
		 */
		return target;
	} else
		return &uuid_null;
}

static void reap_victim(struct nd_mapping *nd_mapping,
		struct nd_label_ent *victim)
{
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	u32 slot = to_slot(ndd, victim->label);

	dev_dbg(ndd->dev, "free: %d\n", slot);
	nd_label_free_slot(ndd, slot);
	victim->label = NULL;
}

static void nsl_set_type_guid(struct nvdimm_drvdata *ndd,
			      struct nd_namespace_label *nd_label, guid_t *guid)
{
	if (efi_namespace_label_has(ndd, type_guid))
		guid_copy(&nd_label->efi.type_guid, guid);
}

bool nsl_validate_type_guid(struct nvdimm_drvdata *ndd,
			    struct nd_namespace_label *nd_label, guid_t *guid)
{
	if (ndd->cxl || !efi_namespace_label_has(ndd, type_guid))
		return true;
	if (!guid_equal(&nd_label->efi.type_guid, guid)) {
		dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n", guid,
			&nd_label->efi.type_guid);
		return false;
	}
	return true;
}

static void nsl_set_claim_class(struct nvdimm_drvdata *ndd,
				struct nd_namespace_label *nd_label,
				enum nvdimm_claim_class claim_class)
{
	if (ndd->cxl) {
		uuid_t uuid;

		import_uuid(&uuid, nd_label->cxl.abstraction_uuid);
		export_uuid(nd_label->cxl.abstraction_uuid,
			    to_abstraction_uuid(claim_class, &uuid));
		return;
	}

	if (!efi_namespace_label_has(ndd, abstraction_guid))
		return;
	guid_copy(&nd_label->efi.abstraction_guid,
		  to_abstraction_guid(claim_class,
				      &nd_label->efi.abstraction_guid));
}

enum nvdimm_claim_class nsl_get_claim_class(struct nvdimm_drvdata *ndd,
					    struct nd_namespace_label *nd_label)
{
	if (ndd->cxl) {
		uuid_t uuid;

		import_uuid(&uuid, nd_label->cxl.abstraction_uuid);
		return uuid_to_nvdimm_cclass(&uuid);
	}
	if (!efi_namespace_label_has(ndd, abstraction_guid))
		return NVDIMM_CCLASS_NONE;
	return guid_to_nvdimm_cclass(&nd_label->efi.abstraction_guid);
}

static int __pmem_label_update(struct nd_region *nd_region,
		struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
		int pos, unsigned long flags)
{
	struct nd_namespace_common *ndns = &nspm->nsio.common;
	struct nd_interleave_set *nd_set = nd_region->nd_set;
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	struct nd_namespace_label *nd_label;
	struct nd_namespace_index *nsindex;
	struct nd_label_ent *label_ent;
	struct nd_label_id label_id;
	struct resource *res;
	unsigned long *free;
	u32 nslot, slot;
	size_t offset;
	u64 cookie;
	int rc;

	if (!preamble_next(ndd, &nsindex, &free, &nslot))
		return -ENXIO;

	cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
	nd_label_gen_id(&label_id, nspm->uuid, 0);
	for_each_dpa_resource(ndd, res)
		if (strcmp(res->name, label_id.id) == 0)
			break;

	if (!res) {
		WARN_ON_ONCE(1);
		return -ENXIO;
	}

	/* allocate and write the label to the staging (next) index */
	slot = nd_label_alloc_slot(ndd);
	if (slot == UINT_MAX)
		return -ENXIO;
	dev_dbg(ndd->dev, "allocated: %d\n", slot);

	nd_label = to_label(ndd, slot);
	memset(nd_label, 0, sizeof_namespace_label(ndd));
	nsl_set_uuid(ndd, nd_label, nspm->uuid);
	nsl_set_name(ndd, nd_label, nspm->alt_name);
	nsl_set_flags(ndd, nd_label, flags);
	nsl_set_nlabel(ndd, nd_label, nd_region->ndr_mappings);
	nsl_set_nrange(ndd, nd_label, 1);
	nsl_set_position(ndd, nd_label, pos);
	nsl_set_isetcookie(ndd, nd_label, cookie);
	nsl_set_rawsize(ndd, nd_label, resource_size(res));
	nsl_set_lbasize(ndd, nd_label, nspm->lbasize);
	nsl_set_dpa(ndd, nd_label, res->start);
	nsl_set_slot(ndd, nd_label, slot);
	nsl_set_type_guid(ndd, nd_label, &nd_set->type_guid);
	nsl_set_claim_class(ndd, nd_label, ndns->claim_class);
	nsl_calculate_checksum(ndd, nd_label);
	nd_dbg_dpa(nd_region, ndd, res, "\n");

	/* update label */
	offset = nd_label_offset(ndd, nd_label);
	rc = nvdimm_set_config_data(ndd, offset, nd_label,
			sizeof_namespace_label(ndd));
	if (rc < 0)
		return rc;

	/* Garbage collect the previous label */
	mutex_lock(&nd_mapping->lock);
	list_for_each_entry(label_ent, &nd_mapping->labels, list) {
		if (!label_ent->label)
			continue;
		if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags) ||
		    nsl_uuid_equal(ndd, label_ent->label, nspm->uuid))
			reap_victim(nd_mapping, label_ent);
	}

	/* update index */
	rc = nd_label_write_index(ndd, ndd->ns_next,
			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
	if (rc == 0) {
		list_for_each_entry(label_ent, &nd_mapping->labels, list)
			if (!label_ent->label) {
				label_ent->label = nd_label;
				nd_label = NULL;
				break;
			}
		dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
				"failed to track label: %d\n",
				to_slot(ndd, nd_label));
		if (nd_label)
			rc = -ENXIO;
	}
	mutex_unlock(&nd_mapping->lock);

	return rc;
}

static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
{
	int i, old_num_labels = 0;
	struct nd_label_ent *label_ent;
	struct nd_namespace_index *nsindex;
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);

	mutex_lock(&nd_mapping->lock);
	list_for_each_entry(label_ent, &nd_mapping->labels, list)
		old_num_labels++;
	mutex_unlock(&nd_mapping->lock);

	/*
	 * We need to preserve all the old labels for the mapping so
	 * they can be garbage collected after writing the new labels.
	 */
	for (i = old_num_labels; i < num_labels; i++) {
		label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
		if (!label_ent)
			return -ENOMEM;
		mutex_lock(&nd_mapping->lock);
		list_add_tail(&label_ent->list, &nd_mapping->labels);
		mutex_unlock(&nd_mapping->lock);
	}

	if (ndd->ns_current == -1 || ndd->ns_next == -1)
		/* pass */;
	else
		return max(num_labels, old_num_labels);

	nsindex = to_namespace_index(ndd, 0);
	memset(nsindex, 0, ndd->nsarea.config_size);
	for (i = 0; i < 2; i++) {
		int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);

		if (rc)
			return rc;
	}
	ndd->ns_next = 1;
	ndd->ns_current = 0;

	return max(num_labels, old_num_labels);
}

static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
{
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	struct nd_label_ent *label_ent, *e;
	struct nd_namespace_index *nsindex;
	unsigned long *free;
	LIST_HEAD(list);
	u32 nslot, slot;
	int active = 0;

	if (!uuid)
		return 0;

	/* no index || no labels == nothing to delete */
	if (!preamble_next(ndd, &nsindex, &free, &nslot))
		return 0;

	mutex_lock(&nd_mapping->lock);
	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
		struct nd_namespace_label *nd_label = label_ent->label;

		if (!nd_label)
			continue;
		active++;
		if (!nsl_uuid_equal(ndd, nd_label, uuid))
			continue;
		active--;
		slot = to_slot(ndd, nd_label);
		nd_label_free_slot(ndd, slot);
		dev_dbg(ndd->dev, "free: %d\n", slot);
		list_move_tail(&label_ent->list, &list);
		label_ent->label = NULL;
	}
	list_splice_tail_init(&list, &nd_mapping->labels);

	if (active == 0) {
		nd_mapping_free_labels(nd_mapping);
		dev_dbg(ndd->dev, "no more active labels\n");
	}
	mutex_unlock(&nd_mapping->lock);

	return nd_label_write_index(ndd, ndd->ns_next,
			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
}

int nd_pmem_namespace_label_update(struct nd_region *nd_region,
		struct nd_namespace_pmem *nspm, resource_size_t size)
{
	int i, rc;

	for (i = 0; i < nd_region->ndr_mappings; i++) {
		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
		struct resource *res;
		int count = 0;

		if (size == 0) {
			rc = del_labels(nd_mapping, nspm->uuid);
			if (rc)
				return rc;
			continue;
		}

		for_each_dpa_resource(ndd, res)
			if (strncmp(res->name, "pmem", 4) == 0)
				count++;
		WARN_ON_ONCE(!count);

		rc = init_labels(nd_mapping, count);
		if (rc < 0)
			return rc;

		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i,
				NSLABEL_FLAG_UPDATING);
		if (rc)
			return rc;
	}

	if (size == 0)
		return 0;

	/* Clear the UPDATING flag per UEFI 2.7 expectations */
	for (i = 0; i < nd_region->ndr_mappings; i++) {
		struct nd_mapping *nd_mapping = &nd_region->mapping[i];

		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i, 0);
		if (rc)
			return rc;
	}

	return 0;
}

int __init nd_label_init(void)
{
	WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
	WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
	WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
	WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));

	WARN_ON(uuid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_uuid));
	WARN_ON(uuid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_uuid));
	WARN_ON(uuid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_uuid));
	WARN_ON(uuid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_uuid));

	WARN_ON(uuid_parse(CXL_REGION_UUID, &cxl_region_uuid));
	WARN_ON(uuid_parse(CXL_NAMESPACE_UUID, &cxl_namespace_uuid));

	return 0;
}