xref: /linux/drivers/nvdimm/label.c (revision 7effbd18e496a954540fb6319db0d87d28a70496)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4  */
5 #include <linux/device.h>
6 #include <linux/ndctl.h>
7 #include <linux/uuid.h>
8 #include <linux/slab.h>
9 #include <linux/io.h>
10 #include <linux/nd.h>
11 #include "nd-core.h"
12 #include "label.h"
13 #include "nd.h"
14 
15 static guid_t nvdimm_btt_guid;
16 static guid_t nvdimm_btt2_guid;
17 static guid_t nvdimm_pfn_guid;
18 static guid_t nvdimm_dax_guid;
19 
20 static uuid_t nvdimm_btt_uuid;
21 static uuid_t nvdimm_btt2_uuid;
22 static uuid_t nvdimm_pfn_uuid;
23 static uuid_t nvdimm_dax_uuid;
24 
25 static uuid_t cxl_region_uuid;
26 static uuid_t cxl_namespace_uuid;
27 
28 static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";
29 
30 static u32 best_seq(u32 a, u32 b)
31 {
32 	a &= NSINDEX_SEQ_MASK;
33 	b &= NSINDEX_SEQ_MASK;
34 
35 	if (a == 0 || a == b)
36 		return b;
37 	else if (b == 0)
38 		return a;
39 	else if (nd_inc_seq(a) == b)
40 		return b;
41 	else
42 		return a;
43 }
44 
45 unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
46 {
47 	return ndd->nslabel_size;
48 }
49 
50 static size_t __sizeof_namespace_index(u32 nslot)
51 {
52 	return ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
53 			NSINDEX_ALIGN);
54 }
55 
56 static int __nvdimm_num_label_slots(struct nvdimm_drvdata *ndd,
57 		size_t index_size)
58 {
59 	return (ndd->nsarea.config_size - index_size * 2) /
60 			sizeof_namespace_label(ndd);
61 }
62 
63 int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
64 {
65 	u32 tmp_nslot, n;
66 
67 	tmp_nslot = ndd->nsarea.config_size / sizeof_namespace_label(ndd);
68 	n = __sizeof_namespace_index(tmp_nslot) / NSINDEX_ALIGN;
69 
70 	return __nvdimm_num_label_slots(ndd, NSINDEX_ALIGN * n);
71 }
72 
73 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
74 {
75 	u32 nslot, space, size;
76 
77 	/*
78 	 * Per UEFI 2.7, the minimum size of the Label Storage Area is large
79 	 * enough to hold 2 index blocks and 2 labels.  The minimum index
80 	 * block size is 256 bytes. The label size is 128 for namespaces
81 	 * prior to version 1.2 and at minimum 256 for version 1.2 and later.
82 	 */
83 	nslot = nvdimm_num_label_slots(ndd);
84 	space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
85 	size = __sizeof_namespace_index(nslot) * 2;
86 	if (size <= space && nslot >= 2)
87 		return size / 2;
88 
89 	dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
90 			ndd->nsarea.config_size, sizeof_namespace_label(ndd));
91 	return 0;
92 }
93 
94 static int __nd_label_validate(struct nvdimm_drvdata *ndd)
95 {
96 	/*
97 	 * On media label format consists of two index blocks followed
98 	 * by an array of labels.  None of these structures are ever
99 	 * updated in place.  A sequence number tracks the current
100 	 * active index and the next one to write, while labels are
101 	 * written to free slots.
102 	 *
103 	 *     +------------+
104 	 *     |            |
105 	 *     |  nsindex0  |
106 	 *     |            |
107 	 *     +------------+
108 	 *     |            |
109 	 *     |  nsindex1  |
110 	 *     |            |
111 	 *     +------------+
112 	 *     |   label0   |
113 	 *     +------------+
114 	 *     |   label1   |
115 	 *     +------------+
116 	 *     |            |
117 	 *      ....nslot...
118 	 *     |            |
119 	 *     +------------+
120 	 *     |   labelN   |
121 	 *     +------------+
122 	 */
123 	struct nd_namespace_index *nsindex[] = {
124 		to_namespace_index(ndd, 0),
125 		to_namespace_index(ndd, 1),
126 	};
127 	const int num_index = ARRAY_SIZE(nsindex);
128 	struct device *dev = ndd->dev;
129 	bool valid[2] = { 0 };
130 	int i, num_valid = 0;
131 	u32 seq;
132 
133 	for (i = 0; i < num_index; i++) {
134 		u32 nslot;
135 		u8 sig[NSINDEX_SIG_LEN];
136 		u64 sum_save, sum, size;
137 		unsigned int version, labelsize;
138 
139 		memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
140 		if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
141 			dev_dbg(dev, "nsindex%d signature invalid\n", i);
142 			continue;
143 		}
144 
145 		/* label sizes larger than 128 arrived with v1.2 */
146 		version = __le16_to_cpu(nsindex[i]->major) * 100
147 			+ __le16_to_cpu(nsindex[i]->minor);
148 		if (version >= 102)
149 			labelsize = 1 << (7 + nsindex[i]->labelsize);
150 		else
151 			labelsize = 128;
152 
153 		if (labelsize != sizeof_namespace_label(ndd)) {
154 			dev_dbg(dev, "nsindex%d labelsize %d invalid\n",
155 					i, nsindex[i]->labelsize);
156 			continue;
157 		}
158 
159 		sum_save = __le64_to_cpu(nsindex[i]->checksum);
160 		nsindex[i]->checksum = __cpu_to_le64(0);
161 		sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
162 		nsindex[i]->checksum = __cpu_to_le64(sum_save);
163 		if (sum != sum_save) {
164 			dev_dbg(dev, "nsindex%d checksum invalid\n", i);
165 			continue;
166 		}
167 
168 		seq = __le32_to_cpu(nsindex[i]->seq);
169 		if ((seq & NSINDEX_SEQ_MASK) == 0) {
170 			dev_dbg(dev, "nsindex%d sequence: %#x invalid\n", i, seq);
171 			continue;
172 		}
173 
174 		/* sanity check the index against expected values */
175 		if (__le64_to_cpu(nsindex[i]->myoff)
176 				!= i * sizeof_namespace_index(ndd)) {
177 			dev_dbg(dev, "nsindex%d myoff: %#llx invalid\n",
178 					i, (unsigned long long)
179 					__le64_to_cpu(nsindex[i]->myoff));
180 			continue;
181 		}
182 		if (__le64_to_cpu(nsindex[i]->otheroff)
183 				!= (!i) * sizeof_namespace_index(ndd)) {
184 			dev_dbg(dev, "nsindex%d otheroff: %#llx invalid\n",
185 					i, (unsigned long long)
186 					__le64_to_cpu(nsindex[i]->otheroff));
187 			continue;
188 		}
189 		if (__le64_to_cpu(nsindex[i]->labeloff)
190 				!= 2 * sizeof_namespace_index(ndd)) {
191 			dev_dbg(dev, "nsindex%d labeloff: %#llx invalid\n",
192 					i, (unsigned long long)
193 					__le64_to_cpu(nsindex[i]->labeloff));
194 			continue;
195 		}
196 
197 		size = __le64_to_cpu(nsindex[i]->mysize);
198 		if (size > sizeof_namespace_index(ndd)
199 				|| size < sizeof(struct nd_namespace_index)) {
200 			dev_dbg(dev, "nsindex%d mysize: %#llx invalid\n", i, size);
201 			continue;
202 		}
203 
204 		nslot = __le32_to_cpu(nsindex[i]->nslot);
205 		if (nslot * sizeof_namespace_label(ndd)
206 				+ 2 * sizeof_namespace_index(ndd)
207 				> ndd->nsarea.config_size) {
208 			dev_dbg(dev, "nsindex%d nslot: %u invalid, config_size: %#x\n",
209 					i, nslot, ndd->nsarea.config_size);
210 			continue;
211 		}
212 		valid[i] = true;
213 		num_valid++;
214 	}
215 
216 	switch (num_valid) {
217 	case 0:
218 		break;
219 	case 1:
220 		for (i = 0; i < num_index; i++)
221 			if (valid[i])
222 				return i;
223 		/* can't have num_valid > 0 but valid[] = { false, false } */
224 		WARN_ON(1);
225 		break;
226 	default:
227 		/* pick the best index... */
228 		seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
229 				__le32_to_cpu(nsindex[1]->seq));
230 		if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
231 			return 1;
232 		else
233 			return 0;
234 		break;
235 	}
236 
237 	return -1;
238 }
239 
240 static int nd_label_validate(struct nvdimm_drvdata *ndd)
241 {
242 	/*
243 	 * In order to probe for and validate namespace index blocks we
244 	 * need to know the size of the labels, and we can't trust the
245 	 * size of the labels until we validate the index blocks.
246 	 * Resolve this dependency loop by probing for known label
247 	 * sizes, but default to v1.2 256-byte namespace labels if
248 	 * discovery fails.
249 	 */
250 	int label_size[] = { 128, 256 };
251 	int i, rc;
252 
253 	for (i = 0; i < ARRAY_SIZE(label_size); i++) {
254 		ndd->nslabel_size = label_size[i];
255 		rc = __nd_label_validate(ndd);
256 		if (rc >= 0)
257 			return rc;
258 	}
259 
260 	return -1;
261 }
262 
263 static void nd_label_copy(struct nvdimm_drvdata *ndd,
264 			  struct nd_namespace_index *dst,
265 			  struct nd_namespace_index *src)
266 {
267 	/* just exit if either destination or source is NULL */
268 	if (!dst || !src)
269 		return;
270 
271 	memcpy(dst, src, sizeof_namespace_index(ndd));
272 }
273 
274 static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
275 {
276 	void *base = to_namespace_index(ndd, 0);
277 
278 	return base + 2 * sizeof_namespace_index(ndd);
279 }
280 
281 static int to_slot(struct nvdimm_drvdata *ndd,
282 		struct nd_namespace_label *nd_label)
283 {
284 	unsigned long label, base;
285 
286 	label = (unsigned long) nd_label;
287 	base = (unsigned long) nd_label_base(ndd);
288 
289 	return (label - base) / sizeof_namespace_label(ndd);
290 }
291 
292 static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
293 {
294 	unsigned long label, base;
295 
296 	base = (unsigned long) nd_label_base(ndd);
297 	label = base + sizeof_namespace_label(ndd) * slot;
298 
299 	return (struct nd_namespace_label *) label;
300 }
301 
302 #define for_each_clear_bit_le(bit, addr, size) \
303 	for ((bit) = find_next_zero_bit_le((addr), (size), 0);  \
304 	     (bit) < (size);                                    \
305 	     (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))
306 
307 /**
308  * preamble_index - common variable initialization for nd_label_* routines
309  * @ndd: dimm container for the relevant label set
310  * @idx: namespace_index index
311  * @nsindex_out: on return set to the currently active namespace index
312  * @free: on return set to the free label bitmap in the index
313  * @nslot: on return set to the number of slots in the label space
314  */
315 static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
316 		struct nd_namespace_index **nsindex_out,
317 		unsigned long **free, u32 *nslot)
318 {
319 	struct nd_namespace_index *nsindex;
320 
321 	nsindex = to_namespace_index(ndd, idx);
322 	if (nsindex == NULL)
323 		return false;
324 
325 	*free = (unsigned long *) nsindex->free;
326 	*nslot = __le32_to_cpu(nsindex->nslot);
327 	*nsindex_out = nsindex;
328 
329 	return true;
330 }
331 
332 char *nd_label_gen_id(struct nd_label_id *label_id, const uuid_t *uuid,
333 		      u32 flags)
334 {
335 	if (!label_id || !uuid)
336 		return NULL;
337 	snprintf(label_id->id, ND_LABEL_ID_SIZE, "pmem-%pUb", uuid);
338 	return label_id->id;
339 }
340 
341 static bool preamble_current(struct nvdimm_drvdata *ndd,
342 		struct nd_namespace_index **nsindex,
343 		unsigned long **free, u32 *nslot)
344 {
345 	return preamble_index(ndd, ndd->ns_current, nsindex,
346 			free, nslot);
347 }
348 
349 static bool preamble_next(struct nvdimm_drvdata *ndd,
350 		struct nd_namespace_index **nsindex,
351 		unsigned long **free, u32 *nslot)
352 {
353 	return preamble_index(ndd, ndd->ns_next, nsindex,
354 			free, nslot);
355 }
356 
357 static bool nsl_validate_checksum(struct nvdimm_drvdata *ndd,
358 				  struct nd_namespace_label *nd_label)
359 {
360 	u64 sum, sum_save;
361 
362 	if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
363 		return true;
364 
365 	sum_save = nsl_get_checksum(ndd, nd_label);
366 	nsl_set_checksum(ndd, nd_label, 0);
367 	sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
368 	nsl_set_checksum(ndd, nd_label, sum_save);
369 	return sum == sum_save;
370 }
371 
372 static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
373 				   struct nd_namespace_label *nd_label)
374 {
375 	u64 sum;
376 
377 	if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
378 		return;
379 	nsl_set_checksum(ndd, nd_label, 0);
380 	sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
381 	nsl_set_checksum(ndd, nd_label, sum);
382 }
383 
384 static bool slot_valid(struct nvdimm_drvdata *ndd,
385 		struct nd_namespace_label *nd_label, u32 slot)
386 {
387 	bool valid;
388 
389 	/* check that we are written where we expect to be written */
390 	if (slot != nsl_get_slot(ndd, nd_label))
391 		return false;
392 	valid = nsl_validate_checksum(ndd, nd_label);
393 	if (!valid)
394 		dev_dbg(ndd->dev, "fail checksum. slot: %d\n", slot);
395 	return valid;
396 }
397 
398 int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
399 {
400 	struct nd_namespace_index *nsindex;
401 	unsigned long *free;
402 	u32 nslot, slot;
403 
404 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
405 		return 0; /* no label, nothing to reserve */
406 
407 	for_each_clear_bit_le(slot, free, nslot) {
408 		struct nd_namespace_label *nd_label;
409 		struct nd_region *nd_region = NULL;
410 		struct nd_label_id label_id;
411 		struct resource *res;
412 		uuid_t label_uuid;
413 		u32 flags;
414 
415 		nd_label = to_label(ndd, slot);
416 
417 		if (!slot_valid(ndd, nd_label, slot))
418 			continue;
419 
420 		nsl_get_uuid(ndd, nd_label, &label_uuid);
421 		flags = nsl_get_flags(ndd, nd_label);
422 		nd_label_gen_id(&label_id, &label_uuid, flags);
423 		res = nvdimm_allocate_dpa(ndd, &label_id,
424 					  nsl_get_dpa(ndd, nd_label),
425 					  nsl_get_rawsize(ndd, nd_label));
426 		nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
427 		if (!res)
428 			return -EBUSY;
429 	}
430 
431 	return 0;
432 }
433 
434 int nd_label_data_init(struct nvdimm_drvdata *ndd)
435 {
436 	size_t config_size, read_size, max_xfer, offset;
437 	struct nd_namespace_index *nsindex;
438 	unsigned int i;
439 	int rc = 0;
440 	u32 nslot;
441 
442 	if (ndd->data)
443 		return 0;
444 
445 	if (ndd->nsarea.status || ndd->nsarea.max_xfer == 0) {
446 		dev_dbg(ndd->dev, "failed to init config data area: (%u:%u)\n",
447 			ndd->nsarea.max_xfer, ndd->nsarea.config_size);
448 		return -ENXIO;
449 	}
450 
451 	/*
452 	 * We need to determine the maximum index area as this is the section
453 	 * we must read and validate before we can start processing labels.
454 	 *
455 	 * If the area is too small to contain the two indexes and 2 labels
456 	 * then we abort.
457 	 *
458 	 * Start at a label size of 128 as this should result in the largest
459 	 * possible namespace index size.
460 	 */
461 	ndd->nslabel_size = 128;
462 	read_size = sizeof_namespace_index(ndd) * 2;
463 	if (!read_size)
464 		return -ENXIO;
465 
466 	/* Allocate config data */
467 	config_size = ndd->nsarea.config_size;
468 	ndd->data = kvzalloc(config_size, GFP_KERNEL);
469 	if (!ndd->data)
470 		return -ENOMEM;
471 
472 	/*
473 	 * We want to guarantee as few reads as possible while conserving
474 	 * memory. To do that we figure out how much unused space will be left
475 	 * in the last read, divide that by the total number of reads it is
476 	 * going to take given our maximum transfer size, and then reduce our
477 	 * maximum transfer size based on that result.
478 	 */
479 	max_xfer = min_t(size_t, ndd->nsarea.max_xfer, config_size);
480 	if (read_size < max_xfer) {
481 		/* trim waste */
482 		max_xfer -= ((max_xfer - 1) - (config_size - 1) % max_xfer) /
483 			    DIV_ROUND_UP(config_size, max_xfer);
484 		/* make certain we read indexes in exactly 1 read */
485 		if (max_xfer < read_size)
486 			max_xfer = read_size;
487 	}
488 
489 	/* Make our initial read size a multiple of max_xfer size */
490 	read_size = min(DIV_ROUND_UP(read_size, max_xfer) * max_xfer,
491 			config_size);
492 
493 	/* Read the index data */
494 	rc = nvdimm_get_config_data(ndd, ndd->data, 0, read_size);
495 	if (rc)
496 		goto out_err;
497 
498 	/* Validate index data, if not valid assume all labels are invalid */
499 	ndd->ns_current = nd_label_validate(ndd);
500 	if (ndd->ns_current < 0)
501 		return 0;
502 
503 	/* Record our index values */
504 	ndd->ns_next = nd_label_next_nsindex(ndd->ns_current);
505 
506 	/* Copy "current" index on top of the "next" index */
507 	nsindex = to_current_namespace_index(ndd);
508 	nd_label_copy(ndd, to_next_namespace_index(ndd), nsindex);
509 
510 	/* Determine starting offset for label data */
511 	offset = __le64_to_cpu(nsindex->labeloff);
512 	nslot = __le32_to_cpu(nsindex->nslot);
513 
514 	/* Loop through the free list pulling in any active labels */
515 	for (i = 0; i < nslot; i++, offset += ndd->nslabel_size) {
516 		size_t label_read_size;
517 
518 		/* zero out the unused labels */
519 		if (test_bit_le(i, nsindex->free)) {
520 			memset(ndd->data + offset, 0, ndd->nslabel_size);
521 			continue;
522 		}
523 
524 		/* if we already read past here then just continue */
525 		if (offset + ndd->nslabel_size <= read_size)
526 			continue;
527 
528 		/* if we haven't read in a while reset our read_size offset */
529 		if (read_size < offset)
530 			read_size = offset;
531 
532 		/* determine how much more will be read after this next call. */
533 		label_read_size = offset + ndd->nslabel_size - read_size;
534 		label_read_size = DIV_ROUND_UP(label_read_size, max_xfer) *
535 				  max_xfer;
536 
537 		/* truncate last read if needed */
538 		if (read_size + label_read_size > config_size)
539 			label_read_size = config_size - read_size;
540 
541 		/* Read the label data */
542 		rc = nvdimm_get_config_data(ndd, ndd->data + read_size,
543 					    read_size, label_read_size);
544 		if (rc)
545 			goto out_err;
546 
547 		/* push read_size to next read offset */
548 		read_size += label_read_size;
549 	}
550 
551 	dev_dbg(ndd->dev, "len: %zu rc: %d\n", offset, rc);
552 out_err:
553 	return rc;
554 }
555 
556 int nd_label_active_count(struct nvdimm_drvdata *ndd)
557 {
558 	struct nd_namespace_index *nsindex;
559 	unsigned long *free;
560 	u32 nslot, slot;
561 	int count = 0;
562 
563 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
564 		return 0;
565 
566 	for_each_clear_bit_le(slot, free, nslot) {
567 		struct nd_namespace_label *nd_label;
568 
569 		nd_label = to_label(ndd, slot);
570 
571 		if (!slot_valid(ndd, nd_label, slot)) {
572 			u32 label_slot = nsl_get_slot(ndd, nd_label);
573 			u64 size = nsl_get_rawsize(ndd, nd_label);
574 			u64 dpa = nsl_get_dpa(ndd, nd_label);
575 
576 			dev_dbg(ndd->dev,
577 				"slot%d invalid slot: %d dpa: %llx size: %llx\n",
578 					slot, label_slot, dpa, size);
579 			continue;
580 		}
581 		count++;
582 	}
583 	return count;
584 }
585 
586 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
587 {
588 	struct nd_namespace_index *nsindex;
589 	unsigned long *free;
590 	u32 nslot, slot;
591 
592 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
593 		return NULL;
594 
595 	for_each_clear_bit_le(slot, free, nslot) {
596 		struct nd_namespace_label *nd_label;
597 
598 		nd_label = to_label(ndd, slot);
599 		if (!slot_valid(ndd, nd_label, slot))
600 			continue;
601 
602 		if (n-- == 0)
603 			return to_label(ndd, slot);
604 	}
605 
606 	return NULL;
607 }
608 
609 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
610 {
611 	struct nd_namespace_index *nsindex;
612 	unsigned long *free;
613 	u32 nslot, slot;
614 
615 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
616 		return UINT_MAX;
617 
618 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
619 
620 	slot = find_next_bit_le(free, nslot, 0);
621 	if (slot == nslot)
622 		return UINT_MAX;
623 
624 	clear_bit_le(slot, free);
625 
626 	return slot;
627 }
628 
629 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
630 {
631 	struct nd_namespace_index *nsindex;
632 	unsigned long *free;
633 	u32 nslot;
634 
635 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
636 		return false;
637 
638 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
639 
640 	if (slot < nslot)
641 		return !test_and_set_bit_le(slot, free);
642 	return false;
643 }
644 
645 u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
646 {
647 	struct nd_namespace_index *nsindex;
648 	unsigned long *free;
649 	u32 nslot;
650 
651 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
652 
653 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
654 		return nvdimm_num_label_slots(ndd);
655 
656 	return bitmap_weight(free, nslot);
657 }
658 
659 static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
660 		unsigned long flags)
661 {
662 	struct nd_namespace_index *nsindex;
663 	unsigned long offset;
664 	u64 checksum;
665 	u32 nslot;
666 	int rc;
667 
668 	nsindex = to_namespace_index(ndd, index);
669 	if (flags & ND_NSINDEX_INIT)
670 		nslot = nvdimm_num_label_slots(ndd);
671 	else
672 		nslot = __le32_to_cpu(nsindex->nslot);
673 
674 	memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
675 	memset(&nsindex->flags, 0, 3);
676 	nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
677 	nsindex->seq = __cpu_to_le32(seq);
678 	offset = (unsigned long) nsindex
679 		- (unsigned long) to_namespace_index(ndd, 0);
680 	nsindex->myoff = __cpu_to_le64(offset);
681 	nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
682 	offset = (unsigned long) to_namespace_index(ndd,
683 			nd_label_next_nsindex(index))
684 		- (unsigned long) to_namespace_index(ndd, 0);
685 	nsindex->otheroff = __cpu_to_le64(offset);
686 	offset = (unsigned long) nd_label_base(ndd)
687 		- (unsigned long) to_namespace_index(ndd, 0);
688 	nsindex->labeloff = __cpu_to_le64(offset);
689 	nsindex->nslot = __cpu_to_le32(nslot);
690 	nsindex->major = __cpu_to_le16(1);
691 	if (sizeof_namespace_label(ndd) < 256)
692 		nsindex->minor = __cpu_to_le16(1);
693 	else
694 		nsindex->minor = __cpu_to_le16(2);
695 	nsindex->checksum = __cpu_to_le64(0);
696 	if (flags & ND_NSINDEX_INIT) {
697 		unsigned long *free = (unsigned long *) nsindex->free;
698 		u32 nfree = ALIGN(nslot, BITS_PER_LONG);
699 		int last_bits, i;
700 
701 		memset(nsindex->free, 0xff, nfree / 8);
702 		for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
703 			clear_bit_le(nslot + i, free);
704 	}
705 	checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
706 	nsindex->checksum = __cpu_to_le64(checksum);
707 	rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
708 			nsindex, sizeof_namespace_index(ndd));
709 	if (rc < 0)
710 		return rc;
711 
712 	if (flags & ND_NSINDEX_INIT)
713 		return 0;
714 
715 	/* copy the index we just wrote to the new 'next' */
716 	WARN_ON(index != ndd->ns_next);
717 	nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
718 	ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
719 	ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
720 	WARN_ON(ndd->ns_current == ndd->ns_next);
721 
722 	return 0;
723 }
724 
725 static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
726 		struct nd_namespace_label *nd_label)
727 {
728 	return (unsigned long) nd_label
729 		- (unsigned long) to_namespace_index(ndd, 0);
730 }
731 
732 static enum nvdimm_claim_class guid_to_nvdimm_cclass(guid_t *guid)
733 {
734 	if (guid_equal(guid, &nvdimm_btt_guid))
735 		return NVDIMM_CCLASS_BTT;
736 	else if (guid_equal(guid, &nvdimm_btt2_guid))
737 		return NVDIMM_CCLASS_BTT2;
738 	else if (guid_equal(guid, &nvdimm_pfn_guid))
739 		return NVDIMM_CCLASS_PFN;
740 	else if (guid_equal(guid, &nvdimm_dax_guid))
741 		return NVDIMM_CCLASS_DAX;
742 	else if (guid_equal(guid, &guid_null))
743 		return NVDIMM_CCLASS_NONE;
744 
745 	return NVDIMM_CCLASS_UNKNOWN;
746 }
747 
748 /* CXL labels store UUIDs instead of GUIDs for the same data */
749 static enum nvdimm_claim_class uuid_to_nvdimm_cclass(uuid_t *uuid)
750 {
751 	if (uuid_equal(uuid, &nvdimm_btt_uuid))
752 		return NVDIMM_CCLASS_BTT;
753 	else if (uuid_equal(uuid, &nvdimm_btt2_uuid))
754 		return NVDIMM_CCLASS_BTT2;
755 	else if (uuid_equal(uuid, &nvdimm_pfn_uuid))
756 		return NVDIMM_CCLASS_PFN;
757 	else if (uuid_equal(uuid, &nvdimm_dax_uuid))
758 		return NVDIMM_CCLASS_DAX;
759 	else if (uuid_equal(uuid, &uuid_null))
760 		return NVDIMM_CCLASS_NONE;
761 
762 	return NVDIMM_CCLASS_UNKNOWN;
763 }
764 
765 static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
766 	guid_t *target)
767 {
768 	if (claim_class == NVDIMM_CCLASS_BTT)
769 		return &nvdimm_btt_guid;
770 	else if (claim_class == NVDIMM_CCLASS_BTT2)
771 		return &nvdimm_btt2_guid;
772 	else if (claim_class == NVDIMM_CCLASS_PFN)
773 		return &nvdimm_pfn_guid;
774 	else if (claim_class == NVDIMM_CCLASS_DAX)
775 		return &nvdimm_dax_guid;
776 	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
777 		/*
778 		 * If we're modifying a namespace for which we don't
779 		 * know the claim_class, don't touch the existing guid.
780 		 */
781 		return target;
782 	} else
783 		return &guid_null;
784 }
785 
786 /* CXL labels store UUIDs instead of GUIDs for the same data */
787 static const uuid_t *to_abstraction_uuid(enum nvdimm_claim_class claim_class,
788 					 uuid_t *target)
789 {
790 	if (claim_class == NVDIMM_CCLASS_BTT)
791 		return &nvdimm_btt_uuid;
792 	else if (claim_class == NVDIMM_CCLASS_BTT2)
793 		return &nvdimm_btt2_uuid;
794 	else if (claim_class == NVDIMM_CCLASS_PFN)
795 		return &nvdimm_pfn_uuid;
796 	else if (claim_class == NVDIMM_CCLASS_DAX)
797 		return &nvdimm_dax_uuid;
798 	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
799 		/*
800 		 * If we're modifying a namespace for which we don't
801 		 * know the claim_class, don't touch the existing uuid.
802 		 */
803 		return target;
804 	} else
805 		return &uuid_null;
806 }
807 
808 static void reap_victim(struct nd_mapping *nd_mapping,
809 		struct nd_label_ent *victim)
810 {
811 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
812 	u32 slot = to_slot(ndd, victim->label);
813 
814 	dev_dbg(ndd->dev, "free: %d\n", slot);
815 	nd_label_free_slot(ndd, slot);
816 	victim->label = NULL;
817 }
818 
819 static void nsl_set_type_guid(struct nvdimm_drvdata *ndd,
820 			      struct nd_namespace_label *nd_label, guid_t *guid)
821 {
822 	if (efi_namespace_label_has(ndd, type_guid))
823 		guid_copy(&nd_label->efi.type_guid, guid);
824 }
825 
826 bool nsl_validate_type_guid(struct nvdimm_drvdata *ndd,
827 			    struct nd_namespace_label *nd_label, guid_t *guid)
828 {
829 	if (ndd->cxl || !efi_namespace_label_has(ndd, type_guid))
830 		return true;
831 	if (!guid_equal(&nd_label->efi.type_guid, guid)) {
832 		dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n", guid,
833 			&nd_label->efi.type_guid);
834 		return false;
835 	}
836 	return true;
837 }
838 
839 static void nsl_set_claim_class(struct nvdimm_drvdata *ndd,
840 				struct nd_namespace_label *nd_label,
841 				enum nvdimm_claim_class claim_class)
842 {
843 	if (ndd->cxl) {
844 		uuid_t uuid;
845 
846 		import_uuid(&uuid, nd_label->cxl.abstraction_uuid);
847 		export_uuid(nd_label->cxl.abstraction_uuid,
848 			    to_abstraction_uuid(claim_class, &uuid));
849 		return;
850 	}
851 
852 	if (!efi_namespace_label_has(ndd, abstraction_guid))
853 		return;
854 	guid_copy(&nd_label->efi.abstraction_guid,
855 		  to_abstraction_guid(claim_class,
856 				      &nd_label->efi.abstraction_guid));
857 }
858 
859 enum nvdimm_claim_class nsl_get_claim_class(struct nvdimm_drvdata *ndd,
860 					    struct nd_namespace_label *nd_label)
861 {
862 	if (ndd->cxl) {
863 		uuid_t uuid;
864 
865 		import_uuid(&uuid, nd_label->cxl.abstraction_uuid);
866 		return uuid_to_nvdimm_cclass(&uuid);
867 	}
868 	if (!efi_namespace_label_has(ndd, abstraction_guid))
869 		return NVDIMM_CCLASS_NONE;
870 	return guid_to_nvdimm_cclass(&nd_label->efi.abstraction_guid);
871 }
872 
873 static int __pmem_label_update(struct nd_region *nd_region,
874 		struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
875 		int pos, unsigned long flags)
876 {
877 	struct nd_namespace_common *ndns = &nspm->nsio.common;
878 	struct nd_interleave_set *nd_set = nd_region->nd_set;
879 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
880 	struct nd_namespace_label *nd_label;
881 	struct nd_namespace_index *nsindex;
882 	struct nd_label_ent *label_ent;
883 	struct nd_label_id label_id;
884 	struct resource *res;
885 	unsigned long *free;
886 	u32 nslot, slot;
887 	size_t offset;
888 	u64 cookie;
889 	int rc;
890 
891 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
892 		return -ENXIO;
893 
894 	cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
895 	nd_label_gen_id(&label_id, nspm->uuid, 0);
896 	for_each_dpa_resource(ndd, res)
897 		if (strcmp(res->name, label_id.id) == 0)
898 			break;
899 
900 	if (!res) {
901 		WARN_ON_ONCE(1);
902 		return -ENXIO;
903 	}
904 
905 	/* allocate and write the label to the staging (next) index */
906 	slot = nd_label_alloc_slot(ndd);
907 	if (slot == UINT_MAX)
908 		return -ENXIO;
909 	dev_dbg(ndd->dev, "allocated: %d\n", slot);
910 
911 	nd_label = to_label(ndd, slot);
912 	memset(nd_label, 0, sizeof_namespace_label(ndd));
913 	nsl_set_uuid(ndd, nd_label, nspm->uuid);
914 	nsl_set_name(ndd, nd_label, nspm->alt_name);
915 	nsl_set_flags(ndd, nd_label, flags);
916 	nsl_set_nlabel(ndd, nd_label, nd_region->ndr_mappings);
917 	nsl_set_nrange(ndd, nd_label, 1);
918 	nsl_set_position(ndd, nd_label, pos);
919 	nsl_set_isetcookie(ndd, nd_label, cookie);
920 	nsl_set_rawsize(ndd, nd_label, resource_size(res));
921 	nsl_set_lbasize(ndd, nd_label, nspm->lbasize);
922 	nsl_set_dpa(ndd, nd_label, res->start);
923 	nsl_set_slot(ndd, nd_label, slot);
924 	nsl_set_type_guid(ndd, nd_label, &nd_set->type_guid);
925 	nsl_set_claim_class(ndd, nd_label, ndns->claim_class);
926 	nsl_calculate_checksum(ndd, nd_label);
927 	nd_dbg_dpa(nd_region, ndd, res, "\n");
928 
929 	/* update label */
930 	offset = nd_label_offset(ndd, nd_label);
931 	rc = nvdimm_set_config_data(ndd, offset, nd_label,
932 			sizeof_namespace_label(ndd));
933 	if (rc < 0)
934 		return rc;
935 
936 	/* Garbage collect the previous label */
937 	mutex_lock(&nd_mapping->lock);
938 	list_for_each_entry(label_ent, &nd_mapping->labels, list) {
939 		if (!label_ent->label)
940 			continue;
941 		if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags) ||
942 		    nsl_uuid_equal(ndd, label_ent->label, nspm->uuid))
943 			reap_victim(nd_mapping, label_ent);
944 	}
945 
946 	/* update index */
947 	rc = nd_label_write_index(ndd, ndd->ns_next,
948 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
949 	if (rc == 0) {
950 		list_for_each_entry(label_ent, &nd_mapping->labels, list)
951 			if (!label_ent->label) {
952 				label_ent->label = nd_label;
953 				nd_label = NULL;
954 				break;
955 			}
956 		dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
957 				"failed to track label: %d\n",
958 				to_slot(ndd, nd_label));
959 		if (nd_label)
960 			rc = -ENXIO;
961 	}
962 	mutex_unlock(&nd_mapping->lock);
963 
964 	return rc;
965 }
966 
967 static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
968 {
969 	int i, old_num_labels = 0;
970 	struct nd_label_ent *label_ent;
971 	struct nd_namespace_index *nsindex;
972 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
973 
974 	mutex_lock(&nd_mapping->lock);
975 	list_for_each_entry(label_ent, &nd_mapping->labels, list)
976 		old_num_labels++;
977 	mutex_unlock(&nd_mapping->lock);
978 
979 	/*
980 	 * We need to preserve all the old labels for the mapping so
981 	 * they can be garbage collected after writing the new labels.
982 	 */
983 	for (i = old_num_labels; i < num_labels; i++) {
984 		label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
985 		if (!label_ent)
986 			return -ENOMEM;
987 		mutex_lock(&nd_mapping->lock);
988 		list_add_tail(&label_ent->list, &nd_mapping->labels);
989 		mutex_unlock(&nd_mapping->lock);
990 	}
991 
992 	if (ndd->ns_current == -1 || ndd->ns_next == -1)
993 		/* pass */;
994 	else
995 		return max(num_labels, old_num_labels);
996 
997 	nsindex = to_namespace_index(ndd, 0);
998 	memset(nsindex, 0, ndd->nsarea.config_size);
999 	for (i = 0; i < 2; i++) {
1000 		int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);
1001 
1002 		if (rc)
1003 			return rc;
1004 	}
1005 	ndd->ns_next = 1;
1006 	ndd->ns_current = 0;
1007 
1008 	return max(num_labels, old_num_labels);
1009 }
1010 
1011 static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
1012 {
1013 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1014 	struct nd_label_ent *label_ent, *e;
1015 	struct nd_namespace_index *nsindex;
1016 	unsigned long *free;
1017 	LIST_HEAD(list);
1018 	u32 nslot, slot;
1019 	int active = 0;
1020 
1021 	if (!uuid)
1022 		return 0;
1023 
1024 	/* no index || no labels == nothing to delete */
1025 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
1026 		return 0;
1027 
1028 	mutex_lock(&nd_mapping->lock);
1029 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
1030 		struct nd_namespace_label *nd_label = label_ent->label;
1031 
1032 		if (!nd_label)
1033 			continue;
1034 		active++;
1035 		if (!nsl_uuid_equal(ndd, nd_label, uuid))
1036 			continue;
1037 		active--;
1038 		slot = to_slot(ndd, nd_label);
1039 		nd_label_free_slot(ndd, slot);
1040 		dev_dbg(ndd->dev, "free: %d\n", slot);
1041 		list_move_tail(&label_ent->list, &list);
1042 		label_ent->label = NULL;
1043 	}
1044 	list_splice_tail_init(&list, &nd_mapping->labels);
1045 
1046 	if (active == 0) {
1047 		nd_mapping_free_labels(nd_mapping);
1048 		dev_dbg(ndd->dev, "no more active labels\n");
1049 	}
1050 	mutex_unlock(&nd_mapping->lock);
1051 
1052 	return nd_label_write_index(ndd, ndd->ns_next,
1053 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
1054 }
1055 
1056 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
1057 		struct nd_namespace_pmem *nspm, resource_size_t size)
1058 {
1059 	int i, rc;
1060 
1061 	for (i = 0; i < nd_region->ndr_mappings; i++) {
1062 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1063 		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1064 		struct resource *res;
1065 		int count = 0;
1066 
1067 		if (size == 0) {
1068 			rc = del_labels(nd_mapping, nspm->uuid);
1069 			if (rc)
1070 				return rc;
1071 			continue;
1072 		}
1073 
1074 		for_each_dpa_resource(ndd, res)
1075 			if (strncmp(res->name, "pmem", 4) == 0)
1076 				count++;
1077 		WARN_ON_ONCE(!count);
1078 
1079 		rc = init_labels(nd_mapping, count);
1080 		if (rc < 0)
1081 			return rc;
1082 
1083 		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i,
1084 				NSLABEL_FLAG_UPDATING);
1085 		if (rc)
1086 			return rc;
1087 	}
1088 
1089 	if (size == 0)
1090 		return 0;
1091 
1092 	/* Clear the UPDATING flag per UEFI 2.7 expectations */
1093 	for (i = 0; i < nd_region->ndr_mappings; i++) {
1094 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1095 
1096 		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i, 0);
1097 		if (rc)
1098 			return rc;
1099 	}
1100 
1101 	return 0;
1102 }
1103 
1104 int __init nd_label_init(void)
1105 {
1106 	WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
1107 	WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
1108 	WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
1109 	WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
1110 
1111 	WARN_ON(uuid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_uuid));
1112 	WARN_ON(uuid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_uuid));
1113 	WARN_ON(uuid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_uuid));
1114 	WARN_ON(uuid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_uuid));
1115 
1116 	WARN_ON(uuid_parse(CXL_REGION_UUID, &cxl_region_uuid));
1117 	WARN_ON(uuid_parse(CXL_NAMESPACE_UUID, &cxl_namespace_uuid));
1118 
1119 	return 0;
1120 }
1121