xref: /linux/drivers/nvdimm/label.c (revision e21f9e2e862e9eb3dd64eaddb6256b3e5098660f)
1 /*
2  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  */
13 #include <linux/device.h>
14 #include <linux/ndctl.h>
15 #include <linux/uuid.h>
16 #include <linux/slab.h>
17 #include <linux/io.h>
18 #include <linux/nd.h>
19 #include "nd-core.h"
20 #include "label.h"
21 #include "nd.h"
22 
23 static guid_t nvdimm_btt_guid;
24 static guid_t nvdimm_btt2_guid;
25 static guid_t nvdimm_pfn_guid;
26 static guid_t nvdimm_dax_guid;
27 
28 static u32 best_seq(u32 a, u32 b)
29 {
30 	a &= NSINDEX_SEQ_MASK;
31 	b &= NSINDEX_SEQ_MASK;
32 
33 	if (a == 0 || a == b)
34 		return b;
35 	else if (b == 0)
36 		return a;
37 	else if (nd_inc_seq(a) == b)
38 		return b;
39 	else
40 		return a;
41 }
42 
43 unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
44 {
45 	return ndd->nslabel_size;
46 }
47 
48 static size_t __sizeof_namespace_index(u32 nslot)
49 {
50 	return ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
51 			NSINDEX_ALIGN);
52 }
53 
54 static int __nvdimm_num_label_slots(struct nvdimm_drvdata *ndd,
55 		size_t index_size)
56 {
57 	return (ndd->nsarea.config_size - index_size * 2) /
58 			sizeof_namespace_label(ndd);
59 }
60 
61 int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
62 {
63 	u32 tmp_nslot, n;
64 
65 	tmp_nslot = ndd->nsarea.config_size / sizeof_namespace_label(ndd);
66 	n = __sizeof_namespace_index(tmp_nslot) / NSINDEX_ALIGN;
67 
68 	return __nvdimm_num_label_slots(ndd, NSINDEX_ALIGN * n);
69 }
70 
71 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
72 {
73 	u32 nslot, space, size;
74 
75 	/*
76 	 * Per UEFI 2.7, the minimum size of the Label Storage Area is large
77 	 * enough to hold 2 index blocks and 2 labels.  The minimum index
78 	 * block size is 256 bytes, and the minimum label size is 256 bytes.
79 	 */
80 	nslot = nvdimm_num_label_slots(ndd);
81 	space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
82 	size = __sizeof_namespace_index(nslot) * 2;
83 	if (size <= space && nslot >= 2)
84 		return size / 2;
85 
86 	dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
87 			ndd->nsarea.config_size, sizeof_namespace_label(ndd));
88 	return 0;
89 }
90 
91 static int __nd_label_validate(struct nvdimm_drvdata *ndd)
92 {
93 	/*
94 	 * On media label format consists of two index blocks followed
95 	 * by an array of labels.  None of these structures are ever
96 	 * updated in place.  A sequence number tracks the current
97 	 * active index and the next one to write, while labels are
98 	 * written to free slots.
99 	 *
100 	 *     +------------+
101 	 *     |            |
102 	 *     |  nsindex0  |
103 	 *     |            |
104 	 *     +------------+
105 	 *     |            |
106 	 *     |  nsindex1  |
107 	 *     |            |
108 	 *     +------------+
109 	 *     |   label0   |
110 	 *     +------------+
111 	 *     |   label1   |
112 	 *     +------------+
113 	 *     |            |
114 	 *      ....nslot...
115 	 *     |            |
116 	 *     +------------+
117 	 *     |   labelN   |
118 	 *     +------------+
119 	 */
120 	struct nd_namespace_index *nsindex[] = {
121 		to_namespace_index(ndd, 0),
122 		to_namespace_index(ndd, 1),
123 	};
124 	const int num_index = ARRAY_SIZE(nsindex);
125 	struct device *dev = ndd->dev;
126 	bool valid[2] = { 0 };
127 	int i, num_valid = 0;
128 	u32 seq;
129 
130 	for (i = 0; i < num_index; i++) {
131 		u32 nslot;
132 		u8 sig[NSINDEX_SIG_LEN];
133 		u64 sum_save, sum, size;
134 		unsigned int version, labelsize;
135 
136 		memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
137 		if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
138 			dev_dbg(dev, "nsindex%d signature invalid\n", i);
139 			continue;
140 		}
141 
142 		/* label sizes larger than 128 arrived with v1.2 */
143 		version = __le16_to_cpu(nsindex[i]->major) * 100
144 			+ __le16_to_cpu(nsindex[i]->minor);
145 		if (version >= 102)
146 			labelsize = 1 << (7 + nsindex[i]->labelsize);
147 		else
148 			labelsize = 128;
149 
150 		if (labelsize != sizeof_namespace_label(ndd)) {
151 			dev_dbg(dev, "nsindex%d labelsize %d invalid\n",
152 					i, nsindex[i]->labelsize);
153 			continue;
154 		}
155 
156 		sum_save = __le64_to_cpu(nsindex[i]->checksum);
157 		nsindex[i]->checksum = __cpu_to_le64(0);
158 		sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
159 		nsindex[i]->checksum = __cpu_to_le64(sum_save);
160 		if (sum != sum_save) {
161 			dev_dbg(dev, "nsindex%d checksum invalid\n", i);
162 			continue;
163 		}
164 
165 		seq = __le32_to_cpu(nsindex[i]->seq);
166 		if ((seq & NSINDEX_SEQ_MASK) == 0) {
167 			dev_dbg(dev, "nsindex%d sequence: %#x invalid\n", i, seq);
168 			continue;
169 		}
170 
171 		/* sanity check the index against expected values */
172 		if (__le64_to_cpu(nsindex[i]->myoff)
173 				!= i * sizeof_namespace_index(ndd)) {
174 			dev_dbg(dev, "nsindex%d myoff: %#llx invalid\n",
175 					i, (unsigned long long)
176 					__le64_to_cpu(nsindex[i]->myoff));
177 			continue;
178 		}
179 		if (__le64_to_cpu(nsindex[i]->otheroff)
180 				!= (!i) * sizeof_namespace_index(ndd)) {
181 			dev_dbg(dev, "nsindex%d otheroff: %#llx invalid\n",
182 					i, (unsigned long long)
183 					__le64_to_cpu(nsindex[i]->otheroff));
184 			continue;
185 		}
186 
187 		size = __le64_to_cpu(nsindex[i]->mysize);
188 		if (size > sizeof_namespace_index(ndd)
189 				|| size < sizeof(struct nd_namespace_index)) {
190 			dev_dbg(dev, "nsindex%d mysize: %#llx invalid\n", i, size);
191 			continue;
192 		}
193 
194 		nslot = __le32_to_cpu(nsindex[i]->nslot);
195 		if (nslot * sizeof_namespace_label(ndd)
196 				+ 2 * sizeof_namespace_index(ndd)
197 				> ndd->nsarea.config_size) {
198 			dev_dbg(dev, "nsindex%d nslot: %u invalid, config_size: %#x\n",
199 					i, nslot, ndd->nsarea.config_size);
200 			continue;
201 		}
202 		valid[i] = true;
203 		num_valid++;
204 	}
205 
206 	switch (num_valid) {
207 	case 0:
208 		break;
209 	case 1:
210 		for (i = 0; i < num_index; i++)
211 			if (valid[i])
212 				return i;
213 		/* can't have num_valid > 0 but valid[] = { false, false } */
214 		WARN_ON(1);
215 		break;
216 	default:
217 		/* pick the best index... */
218 		seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
219 				__le32_to_cpu(nsindex[1]->seq));
220 		if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
221 			return 1;
222 		else
223 			return 0;
224 		break;
225 	}
226 
227 	return -1;
228 }
229 
230 int nd_label_validate(struct nvdimm_drvdata *ndd)
231 {
232 	/*
233 	 * In order to probe for and validate namespace index blocks we
234 	 * need to know the size of the labels, and we can't trust the
235 	 * size of the labels until we validate the index blocks.
236 	 * Resolve this dependency loop by probing for known label
237 	 * sizes, but default to v1.2 256-byte namespace labels if
238 	 * discovery fails.
239 	 */
240 	int label_size[] = { 128, 256 };
241 	int i, rc;
242 
243 	for (i = 0; i < ARRAY_SIZE(label_size); i++) {
244 		ndd->nslabel_size = label_size[i];
245 		rc = __nd_label_validate(ndd);
246 		if (rc >= 0)
247 			return rc;
248 	}
249 
250 	return -1;
251 }
252 
253 void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
254 		struct nd_namespace_index *src)
255 {
256 	if (dst && src)
257 		/* pass */;
258 	else
259 		return;
260 
261 	memcpy(dst, src, sizeof_namespace_index(ndd));
262 }
263 
264 static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
265 {
266 	void *base = to_namespace_index(ndd, 0);
267 
268 	return base + 2 * sizeof_namespace_index(ndd);
269 }
270 
271 static int to_slot(struct nvdimm_drvdata *ndd,
272 		struct nd_namespace_label *nd_label)
273 {
274 	unsigned long label, base;
275 
276 	label = (unsigned long) nd_label;
277 	base = (unsigned long) nd_label_base(ndd);
278 
279 	return (label - base) / sizeof_namespace_label(ndd);
280 }
281 
282 static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
283 {
284 	unsigned long label, base;
285 
286 	base = (unsigned long) nd_label_base(ndd);
287 	label = base + sizeof_namespace_label(ndd) * slot;
288 
289 	return (struct nd_namespace_label *) label;
290 }
291 
292 #define for_each_clear_bit_le(bit, addr, size) \
293 	for ((bit) = find_next_zero_bit_le((addr), (size), 0);  \
294 	     (bit) < (size);                                    \
295 	     (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))
296 
297 /**
298  * preamble_index - common variable initialization for nd_label_* routines
299  * @ndd: dimm container for the relevant label set
300  * @idx: namespace_index index
301  * @nsindex_out: on return set to the currently active namespace index
302  * @free: on return set to the free label bitmap in the index
303  * @nslot: on return set to the number of slots in the label space
304  */
305 static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
306 		struct nd_namespace_index **nsindex_out,
307 		unsigned long **free, u32 *nslot)
308 {
309 	struct nd_namespace_index *nsindex;
310 
311 	nsindex = to_namespace_index(ndd, idx);
312 	if (nsindex == NULL)
313 		return false;
314 
315 	*free = (unsigned long *) nsindex->free;
316 	*nslot = __le32_to_cpu(nsindex->nslot);
317 	*nsindex_out = nsindex;
318 
319 	return true;
320 }
321 
322 char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags)
323 {
324 	if (!label_id || !uuid)
325 		return NULL;
326 	snprintf(label_id->id, ND_LABEL_ID_SIZE, "%s-%pUb",
327 			flags & NSLABEL_FLAG_LOCAL ? "blk" : "pmem", uuid);
328 	return label_id->id;
329 }
330 
331 static bool preamble_current(struct nvdimm_drvdata *ndd,
332 		struct nd_namespace_index **nsindex,
333 		unsigned long **free, u32 *nslot)
334 {
335 	return preamble_index(ndd, ndd->ns_current, nsindex,
336 			free, nslot);
337 }
338 
339 static bool preamble_next(struct nvdimm_drvdata *ndd,
340 		struct nd_namespace_index **nsindex,
341 		unsigned long **free, u32 *nslot)
342 {
343 	return preamble_index(ndd, ndd->ns_next, nsindex,
344 			free, nslot);
345 }
346 
347 static bool slot_valid(struct nvdimm_drvdata *ndd,
348 		struct nd_namespace_label *nd_label, u32 slot)
349 {
350 	/* check that we are written where we expect to be written */
351 	if (slot != __le32_to_cpu(nd_label->slot))
352 		return false;
353 
354 	/* check that DPA allocations are page aligned */
355 	if ((__le64_to_cpu(nd_label->dpa)
356 				| __le64_to_cpu(nd_label->rawsize)) % SZ_4K)
357 		return false;
358 
359 	/* check checksum */
360 	if (namespace_label_has(ndd, checksum)) {
361 		u64 sum, sum_save;
362 
363 		sum_save = __le64_to_cpu(nd_label->checksum);
364 		nd_label->checksum = __cpu_to_le64(0);
365 		sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
366 		nd_label->checksum = __cpu_to_le64(sum_save);
367 		if (sum != sum_save) {
368 			dev_dbg(ndd->dev, "fail checksum. slot: %d expect: %#llx\n",
369 				slot, sum);
370 			return false;
371 		}
372 	}
373 
374 	return true;
375 }
376 
377 int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
378 {
379 	struct nd_namespace_index *nsindex;
380 	unsigned long *free;
381 	u32 nslot, slot;
382 
383 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
384 		return 0; /* no label, nothing to reserve */
385 
386 	for_each_clear_bit_le(slot, free, nslot) {
387 		struct nd_namespace_label *nd_label;
388 		struct nd_region *nd_region = NULL;
389 		u8 label_uuid[NSLABEL_UUID_LEN];
390 		struct nd_label_id label_id;
391 		struct resource *res;
392 		u32 flags;
393 
394 		nd_label = to_label(ndd, slot);
395 
396 		if (!slot_valid(ndd, nd_label, slot))
397 			continue;
398 
399 		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
400 		flags = __le32_to_cpu(nd_label->flags);
401 		nd_label_gen_id(&label_id, label_uuid, flags);
402 		res = nvdimm_allocate_dpa(ndd, &label_id,
403 				__le64_to_cpu(nd_label->dpa),
404 				__le64_to_cpu(nd_label->rawsize));
405 		nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
406 		if (!res)
407 			return -EBUSY;
408 	}
409 
410 	return 0;
411 }
412 
413 int nd_label_active_count(struct nvdimm_drvdata *ndd)
414 {
415 	struct nd_namespace_index *nsindex;
416 	unsigned long *free;
417 	u32 nslot, slot;
418 	int count = 0;
419 
420 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
421 		return 0;
422 
423 	for_each_clear_bit_le(slot, free, nslot) {
424 		struct nd_namespace_label *nd_label;
425 
426 		nd_label = to_label(ndd, slot);
427 
428 		if (!slot_valid(ndd, nd_label, slot)) {
429 			u32 label_slot = __le32_to_cpu(nd_label->slot);
430 			u64 size = __le64_to_cpu(nd_label->rawsize);
431 			u64 dpa = __le64_to_cpu(nd_label->dpa);
432 
433 			dev_dbg(ndd->dev,
434 				"slot%d invalid slot: %d dpa: %llx size: %llx\n",
435 					slot, label_slot, dpa, size);
436 			continue;
437 		}
438 		count++;
439 	}
440 	return count;
441 }
442 
443 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
444 {
445 	struct nd_namespace_index *nsindex;
446 	unsigned long *free;
447 	u32 nslot, slot;
448 
449 	if (!preamble_current(ndd, &nsindex, &free, &nslot))
450 		return NULL;
451 
452 	for_each_clear_bit_le(slot, free, nslot) {
453 		struct nd_namespace_label *nd_label;
454 
455 		nd_label = to_label(ndd, slot);
456 		if (!slot_valid(ndd, nd_label, slot))
457 			continue;
458 
459 		if (n-- == 0)
460 			return to_label(ndd, slot);
461 	}
462 
463 	return NULL;
464 }
465 
466 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
467 {
468 	struct nd_namespace_index *nsindex;
469 	unsigned long *free;
470 	u32 nslot, slot;
471 
472 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
473 		return UINT_MAX;
474 
475 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
476 
477 	slot = find_next_bit_le(free, nslot, 0);
478 	if (slot == nslot)
479 		return UINT_MAX;
480 
481 	clear_bit_le(slot, free);
482 
483 	return slot;
484 }
485 
486 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
487 {
488 	struct nd_namespace_index *nsindex;
489 	unsigned long *free;
490 	u32 nslot;
491 
492 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
493 		return false;
494 
495 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
496 
497 	if (slot < nslot)
498 		return !test_and_set_bit_le(slot, free);
499 	return false;
500 }
501 
502 u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
503 {
504 	struct nd_namespace_index *nsindex;
505 	unsigned long *free;
506 	u32 nslot;
507 
508 	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
509 
510 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
511 		return nvdimm_num_label_slots(ndd);
512 
513 	return bitmap_weight(free, nslot);
514 }
515 
516 static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
517 		unsigned long flags)
518 {
519 	struct nd_namespace_index *nsindex;
520 	unsigned long offset;
521 	u64 checksum;
522 	u32 nslot;
523 	int rc;
524 
525 	nsindex = to_namespace_index(ndd, index);
526 	if (flags & ND_NSINDEX_INIT)
527 		nslot = nvdimm_num_label_slots(ndd);
528 	else
529 		nslot = __le32_to_cpu(nsindex->nslot);
530 
531 	memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
532 	memset(&nsindex->flags, 0, 3);
533 	nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
534 	nsindex->seq = __cpu_to_le32(seq);
535 	offset = (unsigned long) nsindex
536 		- (unsigned long) to_namespace_index(ndd, 0);
537 	nsindex->myoff = __cpu_to_le64(offset);
538 	nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
539 	offset = (unsigned long) to_namespace_index(ndd,
540 			nd_label_next_nsindex(index))
541 		- (unsigned long) to_namespace_index(ndd, 0);
542 	nsindex->otheroff = __cpu_to_le64(offset);
543 	offset = (unsigned long) nd_label_base(ndd)
544 		- (unsigned long) to_namespace_index(ndd, 0);
545 	nsindex->labeloff = __cpu_to_le64(offset);
546 	nsindex->nslot = __cpu_to_le32(nslot);
547 	nsindex->major = __cpu_to_le16(1);
548 	if (sizeof_namespace_label(ndd) < 256)
549 		nsindex->minor = __cpu_to_le16(1);
550 	else
551 		nsindex->minor = __cpu_to_le16(2);
552 	nsindex->checksum = __cpu_to_le64(0);
553 	if (flags & ND_NSINDEX_INIT) {
554 		unsigned long *free = (unsigned long *) nsindex->free;
555 		u32 nfree = ALIGN(nslot, BITS_PER_LONG);
556 		int last_bits, i;
557 
558 		memset(nsindex->free, 0xff, nfree / 8);
559 		for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
560 			clear_bit_le(nslot + i, free);
561 	}
562 	checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
563 	nsindex->checksum = __cpu_to_le64(checksum);
564 	rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
565 			nsindex, sizeof_namespace_index(ndd));
566 	if (rc < 0)
567 		return rc;
568 
569 	if (flags & ND_NSINDEX_INIT)
570 		return 0;
571 
572 	/* copy the index we just wrote to the new 'next' */
573 	WARN_ON(index != ndd->ns_next);
574 	nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
575 	ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
576 	ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
577 	WARN_ON(ndd->ns_current == ndd->ns_next);
578 
579 	return 0;
580 }
581 
582 static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
583 		struct nd_namespace_label *nd_label)
584 {
585 	return (unsigned long) nd_label
586 		- (unsigned long) to_namespace_index(ndd, 0);
587 }
588 
589 enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
590 {
591 	if (guid_equal(guid, &nvdimm_btt_guid))
592 		return NVDIMM_CCLASS_BTT;
593 	else if (guid_equal(guid, &nvdimm_btt2_guid))
594 		return NVDIMM_CCLASS_BTT2;
595 	else if (guid_equal(guid, &nvdimm_pfn_guid))
596 		return NVDIMM_CCLASS_PFN;
597 	else if (guid_equal(guid, &nvdimm_dax_guid))
598 		return NVDIMM_CCLASS_DAX;
599 	else if (guid_equal(guid, &guid_null))
600 		return NVDIMM_CCLASS_NONE;
601 
602 	return NVDIMM_CCLASS_UNKNOWN;
603 }
604 
605 static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
606 	guid_t *target)
607 {
608 	if (claim_class == NVDIMM_CCLASS_BTT)
609 		return &nvdimm_btt_guid;
610 	else if (claim_class == NVDIMM_CCLASS_BTT2)
611 		return &nvdimm_btt2_guid;
612 	else if (claim_class == NVDIMM_CCLASS_PFN)
613 		return &nvdimm_pfn_guid;
614 	else if (claim_class == NVDIMM_CCLASS_DAX)
615 		return &nvdimm_dax_guid;
616 	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
617 		/*
618 		 * If we're modifying a namespace for which we don't
619 		 * know the claim_class, don't touch the existing guid.
620 		 */
621 		return target;
622 	} else
623 		return &guid_null;
624 }
625 
626 static int __pmem_label_update(struct nd_region *nd_region,
627 		struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
628 		int pos)
629 {
630 	struct nd_namespace_common *ndns = &nspm->nsio.common;
631 	struct nd_interleave_set *nd_set = nd_region->nd_set;
632 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
633 	struct nd_label_ent *label_ent, *victim = NULL;
634 	struct nd_namespace_label *nd_label;
635 	struct nd_namespace_index *nsindex;
636 	struct nd_label_id label_id;
637 	struct resource *res;
638 	unsigned long *free;
639 	u32 nslot, slot;
640 	size_t offset;
641 	u64 cookie;
642 	int rc;
643 
644 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
645 		return -ENXIO;
646 
647 	cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
648 	nd_label_gen_id(&label_id, nspm->uuid, 0);
649 	for_each_dpa_resource(ndd, res)
650 		if (strcmp(res->name, label_id.id) == 0)
651 			break;
652 
653 	if (!res) {
654 		WARN_ON_ONCE(1);
655 		return -ENXIO;
656 	}
657 
658 	/* allocate and write the label to the staging (next) index */
659 	slot = nd_label_alloc_slot(ndd);
660 	if (slot == UINT_MAX)
661 		return -ENXIO;
662 	dev_dbg(ndd->dev, "allocated: %d\n", slot);
663 
664 	nd_label = to_label(ndd, slot);
665 	memset(nd_label, 0, sizeof_namespace_label(ndd));
666 	memcpy(nd_label->uuid, nspm->uuid, NSLABEL_UUID_LEN);
667 	if (nspm->alt_name)
668 		memcpy(nd_label->name, nspm->alt_name, NSLABEL_NAME_LEN);
669 	nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_UPDATING);
670 	nd_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
671 	nd_label->position = __cpu_to_le16(pos);
672 	nd_label->isetcookie = __cpu_to_le64(cookie);
673 	nd_label->rawsize = __cpu_to_le64(resource_size(res));
674 	nd_label->lbasize = __cpu_to_le64(nspm->lbasize);
675 	nd_label->dpa = __cpu_to_le64(res->start);
676 	nd_label->slot = __cpu_to_le32(slot);
677 	if (namespace_label_has(ndd, type_guid))
678 		guid_copy(&nd_label->type_guid, &nd_set->type_guid);
679 	if (namespace_label_has(ndd, abstraction_guid))
680 		guid_copy(&nd_label->abstraction_guid,
681 				to_abstraction_guid(ndns->claim_class,
682 					&nd_label->abstraction_guid));
683 	if (namespace_label_has(ndd, checksum)) {
684 		u64 sum;
685 
686 		nd_label->checksum = __cpu_to_le64(0);
687 		sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
688 		nd_label->checksum = __cpu_to_le64(sum);
689 	}
690 	nd_dbg_dpa(nd_region, ndd, res, "\n");
691 
692 	/* update label */
693 	offset = nd_label_offset(ndd, nd_label);
694 	rc = nvdimm_set_config_data(ndd, offset, nd_label,
695 			sizeof_namespace_label(ndd));
696 	if (rc < 0)
697 		return rc;
698 
699 	/* Garbage collect the previous label */
700 	mutex_lock(&nd_mapping->lock);
701 	list_for_each_entry(label_ent, &nd_mapping->labels, list) {
702 		if (!label_ent->label)
703 			continue;
704 		if (memcmp(nspm->uuid, label_ent->label->uuid,
705 					NSLABEL_UUID_LEN) != 0)
706 			continue;
707 		victim = label_ent;
708 		list_move_tail(&victim->list, &nd_mapping->labels);
709 		break;
710 	}
711 	if (victim) {
712 		dev_dbg(ndd->dev, "free: %d\n", slot);
713 		slot = to_slot(ndd, victim->label);
714 		nd_label_free_slot(ndd, slot);
715 		victim->label = NULL;
716 	}
717 
718 	/* update index */
719 	rc = nd_label_write_index(ndd, ndd->ns_next,
720 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
721 	if (rc == 0) {
722 		list_for_each_entry(label_ent, &nd_mapping->labels, list)
723 			if (!label_ent->label) {
724 				label_ent->label = nd_label;
725 				nd_label = NULL;
726 				break;
727 			}
728 		dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
729 				"failed to track label: %d\n",
730 				to_slot(ndd, nd_label));
731 		if (nd_label)
732 			rc = -ENXIO;
733 	}
734 	mutex_unlock(&nd_mapping->lock);
735 
736 	return rc;
737 }
738 
739 static bool is_old_resource(struct resource *res, struct resource **list, int n)
740 {
741 	int i;
742 
743 	if (res->flags & DPA_RESOURCE_ADJUSTED)
744 		return false;
745 	for (i = 0; i < n; i++)
746 		if (res == list[i])
747 			return true;
748 	return false;
749 }
750 
751 static struct resource *to_resource(struct nvdimm_drvdata *ndd,
752 		struct nd_namespace_label *nd_label)
753 {
754 	struct resource *res;
755 
756 	for_each_dpa_resource(ndd, res) {
757 		if (res->start != __le64_to_cpu(nd_label->dpa))
758 			continue;
759 		if (resource_size(res) != __le64_to_cpu(nd_label->rawsize))
760 			continue;
761 		return res;
762 	}
763 
764 	return NULL;
765 }
766 
767 /*
768  * 1/ Account all the labels that can be freed after this update
769  * 2/ Allocate and write the label to the staging (next) index
770  * 3/ Record the resources in the namespace device
771  */
772 static int __blk_label_update(struct nd_region *nd_region,
773 		struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
774 		int num_labels)
775 {
776 	int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
777 	struct nd_interleave_set *nd_set = nd_region->nd_set;
778 	struct nd_namespace_common *ndns = &nsblk->common;
779 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
780 	struct nd_namespace_label *nd_label;
781 	struct nd_label_ent *label_ent, *e;
782 	struct nd_namespace_index *nsindex;
783 	unsigned long *free, *victim_map = NULL;
784 	struct resource *res, **old_res_list;
785 	struct nd_label_id label_id;
786 	u8 uuid[NSLABEL_UUID_LEN];
787 	int min_dpa_idx = 0;
788 	LIST_HEAD(list);
789 	u32 nslot, slot;
790 
791 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
792 		return -ENXIO;
793 
794 	old_res_list = nsblk->res;
795 	nfree = nd_label_nfree(ndd);
796 	old_num_resources = nsblk->num_resources;
797 	nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
798 
799 	/*
800 	 * We need to loop over the old resources a few times, which seems a
801 	 * bit inefficient, but we need to know that we have the label
802 	 * space before we start mutating the tracking structures.
803 	 * Otherwise the recovery method of last resort for userspace is
804 	 * disable and re-enable the parent region.
805 	 */
806 	alloc = 0;
807 	for_each_dpa_resource(ndd, res) {
808 		if (strcmp(res->name, label_id.id) != 0)
809 			continue;
810 		if (!is_old_resource(res, old_res_list, old_num_resources))
811 			alloc++;
812 	}
813 
814 	victims = 0;
815 	if (old_num_resources) {
816 		/* convert old local-label-map to dimm-slot victim-map */
817 		victim_map = kcalloc(BITS_TO_LONGS(nslot), sizeof(long),
818 				GFP_KERNEL);
819 		if (!victim_map)
820 			return -ENOMEM;
821 
822 		/* mark unused labels for garbage collection */
823 		for_each_clear_bit_le(slot, free, nslot) {
824 			nd_label = to_label(ndd, slot);
825 			memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
826 			if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
827 				continue;
828 			res = to_resource(ndd, nd_label);
829 			if (res && is_old_resource(res, old_res_list,
830 						old_num_resources))
831 				continue;
832 			slot = to_slot(ndd, nd_label);
833 			set_bit(slot, victim_map);
834 			victims++;
835 		}
836 	}
837 
838 	/* don't allow updates that consume the last label */
839 	if (nfree - alloc < 0 || nfree - alloc + victims < 1) {
840 		dev_info(&nsblk->common.dev, "insufficient label space\n");
841 		kfree(victim_map);
842 		return -ENOSPC;
843 	}
844 	/* from here on we need to abort on error */
845 
846 
847 	/* assign all resources to the namespace before writing the labels */
848 	nsblk->res = NULL;
849 	nsblk->num_resources = 0;
850 	for_each_dpa_resource(ndd, res) {
851 		if (strcmp(res->name, label_id.id) != 0)
852 			continue;
853 		if (!nsblk_add_resource(nd_region, ndd, nsblk, res->start)) {
854 			rc = -ENOMEM;
855 			goto abort;
856 		}
857 	}
858 
859 	/*
860 	 * Find the resource associated with the first label in the set
861 	 * per the v1.2 namespace specification.
862 	 */
863 	for (i = 0; i < nsblk->num_resources; i++) {
864 		struct resource *min = nsblk->res[min_dpa_idx];
865 
866 		res = nsblk->res[i];
867 		if (res->start < min->start)
868 			min_dpa_idx = i;
869 	}
870 
871 	for (i = 0; i < nsblk->num_resources; i++) {
872 		size_t offset;
873 
874 		res = nsblk->res[i];
875 		if (is_old_resource(res, old_res_list, old_num_resources))
876 			continue; /* carry-over */
877 		slot = nd_label_alloc_slot(ndd);
878 		if (slot == UINT_MAX)
879 			goto abort;
880 		dev_dbg(ndd->dev, "allocated: %d\n", slot);
881 
882 		nd_label = to_label(ndd, slot);
883 		memset(nd_label, 0, sizeof_namespace_label(ndd));
884 		memcpy(nd_label->uuid, nsblk->uuid, NSLABEL_UUID_LEN);
885 		if (nsblk->alt_name)
886 			memcpy(nd_label->name, nsblk->alt_name,
887 					NSLABEL_NAME_LEN);
888 		nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_LOCAL);
889 
890 		/*
891 		 * Use the presence of the type_guid as a flag to
892 		 * determine isetcookie usage and nlabel + position
893 		 * policy for blk-aperture namespaces.
894 		 */
895 		if (namespace_label_has(ndd, type_guid)) {
896 			if (i == min_dpa_idx) {
897 				nd_label->nlabel = __cpu_to_le16(nsblk->num_resources);
898 				nd_label->position = __cpu_to_le16(0);
899 			} else {
900 				nd_label->nlabel = __cpu_to_le16(0xffff);
901 				nd_label->position = __cpu_to_le16(0xffff);
902 			}
903 			nd_label->isetcookie = __cpu_to_le64(nd_set->cookie2);
904 		} else {
905 			nd_label->nlabel = __cpu_to_le16(0); /* N/A */
906 			nd_label->position = __cpu_to_le16(0); /* N/A */
907 			nd_label->isetcookie = __cpu_to_le64(0); /* N/A */
908 		}
909 
910 		nd_label->dpa = __cpu_to_le64(res->start);
911 		nd_label->rawsize = __cpu_to_le64(resource_size(res));
912 		nd_label->lbasize = __cpu_to_le64(nsblk->lbasize);
913 		nd_label->slot = __cpu_to_le32(slot);
914 		if (namespace_label_has(ndd, type_guid))
915 			guid_copy(&nd_label->type_guid, &nd_set->type_guid);
916 		if (namespace_label_has(ndd, abstraction_guid))
917 			guid_copy(&nd_label->abstraction_guid,
918 					to_abstraction_guid(ndns->claim_class,
919 						&nd_label->abstraction_guid));
920 
921 		if (namespace_label_has(ndd, checksum)) {
922 			u64 sum;
923 
924 			nd_label->checksum = __cpu_to_le64(0);
925 			sum = nd_fletcher64(nd_label,
926 					sizeof_namespace_label(ndd), 1);
927 			nd_label->checksum = __cpu_to_le64(sum);
928 		}
929 
930 		/* update label */
931 		offset = nd_label_offset(ndd, nd_label);
932 		rc = nvdimm_set_config_data(ndd, offset, nd_label,
933 				sizeof_namespace_label(ndd));
934 		if (rc < 0)
935 			goto abort;
936 	}
937 
938 	/* free up now unused slots in the new index */
939 	for_each_set_bit(slot, victim_map, victim_map ? nslot : 0) {
940 		dev_dbg(ndd->dev, "free: %d\n", slot);
941 		nd_label_free_slot(ndd, slot);
942 	}
943 
944 	/* update index */
945 	rc = nd_label_write_index(ndd, ndd->ns_next,
946 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
947 	if (rc)
948 		goto abort;
949 
950 	/*
951 	 * Now that the on-dimm labels are up to date, fix up the tracking
952 	 * entries in nd_mapping->labels
953 	 */
954 	nlabel = 0;
955 	mutex_lock(&nd_mapping->lock);
956 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
957 		nd_label = label_ent->label;
958 		if (!nd_label)
959 			continue;
960 		nlabel++;
961 		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
962 		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
963 			continue;
964 		nlabel--;
965 		list_move(&label_ent->list, &list);
966 		label_ent->label = NULL;
967 	}
968 	list_splice_tail_init(&list, &nd_mapping->labels);
969 	mutex_unlock(&nd_mapping->lock);
970 
971 	if (nlabel + nsblk->num_resources > num_labels) {
972 		/*
973 		 * Bug, we can't end up with more resources than
974 		 * available labels
975 		 */
976 		WARN_ON_ONCE(1);
977 		rc = -ENXIO;
978 		goto out;
979 	}
980 
981 	mutex_lock(&nd_mapping->lock);
982 	label_ent = list_first_entry_or_null(&nd_mapping->labels,
983 			typeof(*label_ent), list);
984 	if (!label_ent) {
985 		WARN_ON(1);
986 		mutex_unlock(&nd_mapping->lock);
987 		rc = -ENXIO;
988 		goto out;
989 	}
990 	for_each_clear_bit_le(slot, free, nslot) {
991 		nd_label = to_label(ndd, slot);
992 		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
993 		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
994 			continue;
995 		res = to_resource(ndd, nd_label);
996 		res->flags &= ~DPA_RESOURCE_ADJUSTED;
997 		dev_vdbg(&nsblk->common.dev, "assign label slot: %d\n", slot);
998 		list_for_each_entry_from(label_ent, &nd_mapping->labels, list) {
999 			if (label_ent->label)
1000 				continue;
1001 			label_ent->label = nd_label;
1002 			nd_label = NULL;
1003 			break;
1004 		}
1005 		if (nd_label)
1006 			dev_WARN(&nsblk->common.dev,
1007 					"failed to track label slot%d\n", slot);
1008 	}
1009 	mutex_unlock(&nd_mapping->lock);
1010 
1011  out:
1012 	kfree(old_res_list);
1013 	kfree(victim_map);
1014 	return rc;
1015 
1016  abort:
1017 	/*
1018 	 * 1/ repair the allocated label bitmap in the index
1019 	 * 2/ restore the resource list
1020 	 */
1021 	nd_label_copy(ndd, nsindex, to_current_namespace_index(ndd));
1022 	kfree(nsblk->res);
1023 	nsblk->res = old_res_list;
1024 	nsblk->num_resources = old_num_resources;
1025 	old_res_list = NULL;
1026 	goto out;
1027 }
1028 
1029 static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
1030 {
1031 	int i, old_num_labels = 0;
1032 	struct nd_label_ent *label_ent;
1033 	struct nd_namespace_index *nsindex;
1034 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1035 
1036 	mutex_lock(&nd_mapping->lock);
1037 	list_for_each_entry(label_ent, &nd_mapping->labels, list)
1038 		old_num_labels++;
1039 	mutex_unlock(&nd_mapping->lock);
1040 
1041 	/*
1042 	 * We need to preserve all the old labels for the mapping so
1043 	 * they can be garbage collected after writing the new labels.
1044 	 */
1045 	for (i = old_num_labels; i < num_labels; i++) {
1046 		label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
1047 		if (!label_ent)
1048 			return -ENOMEM;
1049 		mutex_lock(&nd_mapping->lock);
1050 		list_add_tail(&label_ent->list, &nd_mapping->labels);
1051 		mutex_unlock(&nd_mapping->lock);
1052 	}
1053 
1054 	if (ndd->ns_current == -1 || ndd->ns_next == -1)
1055 		/* pass */;
1056 	else
1057 		return max(num_labels, old_num_labels);
1058 
1059 	nsindex = to_namespace_index(ndd, 0);
1060 	memset(nsindex, 0, ndd->nsarea.config_size);
1061 	for (i = 0; i < 2; i++) {
1062 		int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);
1063 
1064 		if (rc)
1065 			return rc;
1066 	}
1067 	ndd->ns_next = 1;
1068 	ndd->ns_current = 0;
1069 
1070 	return max(num_labels, old_num_labels);
1071 }
1072 
1073 static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
1074 {
1075 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1076 	struct nd_label_ent *label_ent, *e;
1077 	struct nd_namespace_index *nsindex;
1078 	u8 label_uuid[NSLABEL_UUID_LEN];
1079 	unsigned long *free;
1080 	LIST_HEAD(list);
1081 	u32 nslot, slot;
1082 	int active = 0;
1083 
1084 	if (!uuid)
1085 		return 0;
1086 
1087 	/* no index || no labels == nothing to delete */
1088 	if (!preamble_next(ndd, &nsindex, &free, &nslot))
1089 		return 0;
1090 
1091 	mutex_lock(&nd_mapping->lock);
1092 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
1093 		struct nd_namespace_label *nd_label = label_ent->label;
1094 
1095 		if (!nd_label)
1096 			continue;
1097 		active++;
1098 		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
1099 		if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
1100 			continue;
1101 		active--;
1102 		slot = to_slot(ndd, nd_label);
1103 		nd_label_free_slot(ndd, slot);
1104 		dev_dbg(ndd->dev, "free: %d\n", slot);
1105 		list_move_tail(&label_ent->list, &list);
1106 		label_ent->label = NULL;
1107 	}
1108 	list_splice_tail_init(&list, &nd_mapping->labels);
1109 
1110 	if (active == 0) {
1111 		nd_mapping_free_labels(nd_mapping);
1112 		dev_dbg(ndd->dev, "no more active labels\n");
1113 	}
1114 	mutex_unlock(&nd_mapping->lock);
1115 
1116 	return nd_label_write_index(ndd, ndd->ns_next,
1117 			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
1118 }
1119 
1120 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
1121 		struct nd_namespace_pmem *nspm, resource_size_t size)
1122 {
1123 	int i;
1124 
1125 	for (i = 0; i < nd_region->ndr_mappings; i++) {
1126 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1127 		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1128 		struct resource *res;
1129 		int rc, count = 0;
1130 
1131 		if (size == 0) {
1132 			rc = del_labels(nd_mapping, nspm->uuid);
1133 			if (rc)
1134 				return rc;
1135 			continue;
1136 		}
1137 
1138 		for_each_dpa_resource(ndd, res)
1139 			if (strncmp(res->name, "pmem", 4) == 0)
1140 				count++;
1141 		WARN_ON_ONCE(!count);
1142 
1143 		rc = init_labels(nd_mapping, count);
1144 		if (rc < 0)
1145 			return rc;
1146 
1147 		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i);
1148 		if (rc)
1149 			return rc;
1150 	}
1151 
1152 	return 0;
1153 }
1154 
1155 int nd_blk_namespace_label_update(struct nd_region *nd_region,
1156 		struct nd_namespace_blk *nsblk, resource_size_t size)
1157 {
1158 	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
1159 	struct resource *res;
1160 	int count = 0;
1161 
1162 	if (size == 0)
1163 		return del_labels(nd_mapping, nsblk->uuid);
1164 
1165 	for_each_dpa_resource(to_ndd(nd_mapping), res)
1166 		count++;
1167 
1168 	count = init_labels(nd_mapping, count);
1169 	if (count < 0)
1170 		return count;
1171 
1172 	return __blk_label_update(nd_region, nd_mapping, nsblk, count);
1173 }
1174 
1175 int __init nd_label_init(void)
1176 {
1177 	WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
1178 	WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
1179 	WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
1180 	WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
1181 
1182 	return 0;
1183 }
1184