1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4 */
5 #include <linux/scatterlist.h>
6 #include <linux/memregion.h>
7 #include <linux/highmem.h>
8 #include <linux/kstrtox.h>
9 #include <linux/sched.h>
10 #include <linux/slab.h>
11 #include <linux/hash.h>
12 #include <linux/sort.h>
13 #include <linux/io.h>
14 #include <linux/nd.h>
15 #include "nd-core.h"
16 #include "nd.h"
17
18 /*
19 * For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
20 * irrelevant.
21 */
22 #include <linux/io-64-nonatomic-hi-lo.h>
23
24 static DEFINE_PER_CPU(int, flush_idx);
25
nvdimm_map_flush(struct device * dev,struct nvdimm * nvdimm,int dimm,struct nd_region_data * ndrd)26 static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm,
27 struct nd_region_data *ndrd)
28 {
29 int i, j;
30
31 dev_dbg(dev, "%s: map %d flush address%s\n", nvdimm_name(nvdimm),
32 nvdimm->num_flush, nvdimm->num_flush == 1 ? "" : "es");
33 for (i = 0; i < (1 << ndrd->hints_shift); i++) {
34 struct resource *res = &nvdimm->flush_wpq[i];
35 unsigned long pfn = PHYS_PFN(res->start);
36 void __iomem *flush_page;
37
38 /* check if flush hints share a page */
39 for (j = 0; j < i; j++) {
40 struct resource *res_j = &nvdimm->flush_wpq[j];
41 unsigned long pfn_j = PHYS_PFN(res_j->start);
42
43 if (pfn == pfn_j)
44 break;
45 }
46
47 if (j < i)
48 flush_page = (void __iomem *) ((unsigned long)
49 ndrd_get_flush_wpq(ndrd, dimm, j)
50 & PAGE_MASK);
51 else
52 flush_page = devm_nvdimm_ioremap(dev,
53 PFN_PHYS(pfn), PAGE_SIZE);
54 if (!flush_page)
55 return -ENXIO;
56 ndrd_set_flush_wpq(ndrd, dimm, i, flush_page
57 + (res->start & ~PAGE_MASK));
58 }
59
60 return 0;
61 }
62
nd_region_invalidate_memregion(struct nd_region * nd_region)63 static int nd_region_invalidate_memregion(struct nd_region *nd_region)
64 {
65 int i, incoherent = 0;
66
67 for (i = 0; i < nd_region->ndr_mappings; i++) {
68 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
69 struct nvdimm *nvdimm = nd_mapping->nvdimm;
70
71 if (test_bit(NDD_INCOHERENT, &nvdimm->flags)) {
72 incoherent++;
73 break;
74 }
75 }
76
77 if (!incoherent)
78 return 0;
79
80 if (!cpu_cache_has_invalidate_memregion()) {
81 if (IS_ENABLED(CONFIG_NVDIMM_SECURITY_TEST)) {
82 dev_warn(
83 &nd_region->dev,
84 "Bypassing cpu_cache_invalidate_memergion() for testing!\n");
85 goto out;
86 } else {
87 dev_err(&nd_region->dev,
88 "Failed to synchronize CPU cache state\n");
89 return -ENXIO;
90 }
91 }
92
93 cpu_cache_invalidate_memregion(IORES_DESC_PERSISTENT_MEMORY);
94 out:
95 for (i = 0; i < nd_region->ndr_mappings; i++) {
96 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
97 struct nvdimm *nvdimm = nd_mapping->nvdimm;
98
99 clear_bit(NDD_INCOHERENT, &nvdimm->flags);
100 }
101
102 return 0;
103 }
104
nd_region_activate(struct nd_region * nd_region)105 int nd_region_activate(struct nd_region *nd_region)
106 {
107 int i, j, rc, num_flush = 0;
108 struct nd_region_data *ndrd;
109 struct device *dev = &nd_region->dev;
110 size_t flush_data_size = sizeof(void *);
111
112 nvdimm_bus_lock(&nd_region->dev);
113 for (i = 0; i < nd_region->ndr_mappings; i++) {
114 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
115 struct nvdimm *nvdimm = nd_mapping->nvdimm;
116
117 if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
118 nvdimm_bus_unlock(&nd_region->dev);
119 return -EBUSY;
120 }
121
122 /* at least one null hint slot per-dimm for the "no-hint" case */
123 flush_data_size += sizeof(void *);
124 num_flush = min_not_zero(num_flush, nvdimm->num_flush);
125 if (!nvdimm->num_flush)
126 continue;
127 flush_data_size += nvdimm->num_flush * sizeof(void *);
128 }
129 nvdimm_bus_unlock(&nd_region->dev);
130
131 rc = nd_region_invalidate_memregion(nd_region);
132 if (rc)
133 return rc;
134
135 ndrd = devm_kzalloc(dev, sizeof(*ndrd) + flush_data_size, GFP_KERNEL);
136 if (!ndrd)
137 return -ENOMEM;
138 dev_set_drvdata(dev, ndrd);
139
140 if (!num_flush)
141 return 0;
142
143 ndrd->hints_shift = ilog2(num_flush);
144 for (i = 0; i < nd_region->ndr_mappings; i++) {
145 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
146 struct nvdimm *nvdimm = nd_mapping->nvdimm;
147 int rc = nvdimm_map_flush(&nd_region->dev, nvdimm, i, ndrd);
148
149 if (rc)
150 return rc;
151 }
152
153 /*
154 * Clear out entries that are duplicates. This should prevent the
155 * extra flushings.
156 */
157 for (i = 0; i < nd_region->ndr_mappings - 1; i++) {
158 /* ignore if NULL already */
159 if (!ndrd_get_flush_wpq(ndrd, i, 0))
160 continue;
161
162 for (j = i + 1; j < nd_region->ndr_mappings; j++)
163 if (ndrd_get_flush_wpq(ndrd, i, 0) ==
164 ndrd_get_flush_wpq(ndrd, j, 0))
165 ndrd_set_flush_wpq(ndrd, j, 0, NULL);
166 }
167
168 return 0;
169 }
170
nd_region_release(struct device * dev)171 static void nd_region_release(struct device *dev)
172 {
173 struct nd_region *nd_region = to_nd_region(dev);
174 u16 i;
175
176 for (i = 0; i < nd_region->ndr_mappings; i++) {
177 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
178 struct nvdimm *nvdimm = nd_mapping->nvdimm;
179
180 put_device(&nvdimm->dev);
181 }
182 free_percpu(nd_region->lane);
183 if (!test_bit(ND_REGION_CXL, &nd_region->flags))
184 memregion_free(nd_region->id);
185 kfree(nd_region);
186 }
187
to_nd_region(struct device * dev)188 struct nd_region *to_nd_region(struct device *dev)
189 {
190 struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
191
192 WARN_ON(dev->type->release != nd_region_release);
193 return nd_region;
194 }
195 EXPORT_SYMBOL_GPL(to_nd_region);
196
nd_region_dev(struct nd_region * nd_region)197 struct device *nd_region_dev(struct nd_region *nd_region)
198 {
199 if (!nd_region)
200 return NULL;
201 return &nd_region->dev;
202 }
203 EXPORT_SYMBOL_GPL(nd_region_dev);
204
nd_region_provider_data(struct nd_region * nd_region)205 void *nd_region_provider_data(struct nd_region *nd_region)
206 {
207 return nd_region->provider_data;
208 }
209 EXPORT_SYMBOL_GPL(nd_region_provider_data);
210
211 /**
212 * nd_region_to_nstype() - region to an integer namespace type
213 * @nd_region: region-device to interrogate
214 *
215 * This is the 'nstype' attribute of a region as well, an input to the
216 * MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
217 * namespace devices with namespace drivers.
218 */
nd_region_to_nstype(struct nd_region * nd_region)219 int nd_region_to_nstype(struct nd_region *nd_region)
220 {
221 if (is_memory(&nd_region->dev)) {
222 u16 i, label;
223
224 for (i = 0, label = 0; i < nd_region->ndr_mappings; i++) {
225 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
226 struct nvdimm *nvdimm = nd_mapping->nvdimm;
227
228 if (test_bit(NDD_LABELING, &nvdimm->flags))
229 label++;
230 }
231 if (label)
232 return ND_DEVICE_NAMESPACE_PMEM;
233 else
234 return ND_DEVICE_NAMESPACE_IO;
235 }
236
237 return 0;
238 }
239 EXPORT_SYMBOL(nd_region_to_nstype);
240
region_size(struct nd_region * nd_region)241 static unsigned long long region_size(struct nd_region *nd_region)
242 {
243 if (is_memory(&nd_region->dev)) {
244 return nd_region->ndr_size;
245 } else if (nd_region->ndr_mappings == 1) {
246 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
247
248 return nd_mapping->size;
249 }
250
251 return 0;
252 }
253
size_show(struct device * dev,struct device_attribute * attr,char * buf)254 static ssize_t size_show(struct device *dev,
255 struct device_attribute *attr, char *buf)
256 {
257 struct nd_region *nd_region = to_nd_region(dev);
258
259 return sprintf(buf, "%llu\n", region_size(nd_region));
260 }
261 static DEVICE_ATTR_RO(size);
262
deep_flush_show(struct device * dev,struct device_attribute * attr,char * buf)263 static ssize_t deep_flush_show(struct device *dev,
264 struct device_attribute *attr, char *buf)
265 {
266 struct nd_region *nd_region = to_nd_region(dev);
267
268 /*
269 * NOTE: in the nvdimm_has_flush() error case this attribute is
270 * not visible.
271 */
272 return sprintf(buf, "%d\n", nvdimm_has_flush(nd_region));
273 }
274
deep_flush_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)275 static ssize_t deep_flush_store(struct device *dev, struct device_attribute *attr,
276 const char *buf, size_t len)
277 {
278 bool flush;
279 int rc = kstrtobool(buf, &flush);
280 struct nd_region *nd_region = to_nd_region(dev);
281
282 if (rc)
283 return rc;
284 if (!flush)
285 return -EINVAL;
286 rc = nvdimm_flush(nd_region, NULL);
287 if (rc)
288 return rc;
289
290 return len;
291 }
292 static DEVICE_ATTR_RW(deep_flush);
293
mappings_show(struct device * dev,struct device_attribute * attr,char * buf)294 static ssize_t mappings_show(struct device *dev,
295 struct device_attribute *attr, char *buf)
296 {
297 struct nd_region *nd_region = to_nd_region(dev);
298
299 return sprintf(buf, "%d\n", nd_region->ndr_mappings);
300 }
301 static DEVICE_ATTR_RO(mappings);
302
nstype_show(struct device * dev,struct device_attribute * attr,char * buf)303 static ssize_t nstype_show(struct device *dev,
304 struct device_attribute *attr, char *buf)
305 {
306 struct nd_region *nd_region = to_nd_region(dev);
307
308 return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
309 }
310 static DEVICE_ATTR_RO(nstype);
311
set_cookie_show(struct device * dev,struct device_attribute * attr,char * buf)312 static ssize_t set_cookie_show(struct device *dev,
313 struct device_attribute *attr, char *buf)
314 {
315 struct nd_region *nd_region = to_nd_region(dev);
316 struct nd_interleave_set *nd_set = nd_region->nd_set;
317 ssize_t rc = 0;
318
319 if (is_memory(dev) && nd_set)
320 /* pass, should be precluded by region_visible */;
321 else
322 return -ENXIO;
323
324 /*
325 * The cookie to show depends on which specification of the
326 * labels we are using. If there are not labels then default to
327 * the v1.1 namespace label cookie definition. To read all this
328 * data we need to wait for probing to settle.
329 */
330 device_lock(dev);
331 nvdimm_bus_lock(dev);
332 wait_nvdimm_bus_probe_idle(dev);
333 if (nd_region->ndr_mappings) {
334 struct nd_mapping *nd_mapping = &nd_region->mapping[0];
335 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
336
337 if (ndd) {
338 struct nd_namespace_index *nsindex;
339
340 nsindex = to_namespace_index(ndd, ndd->ns_current);
341 rc = sprintf(buf, "%#llx\n",
342 nd_region_interleave_set_cookie(nd_region,
343 nsindex));
344 }
345 }
346 nvdimm_bus_unlock(dev);
347 device_unlock(dev);
348
349 if (rc)
350 return rc;
351 return sprintf(buf, "%#llx\n", nd_set->cookie1);
352 }
353 static DEVICE_ATTR_RO(set_cookie);
354
nd_region_available_dpa(struct nd_region * nd_region)355 resource_size_t nd_region_available_dpa(struct nd_region *nd_region)
356 {
357 resource_size_t available;
358 int i;
359
360 WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
361
362 available = 0;
363 for (i = 0; i < nd_region->ndr_mappings; i++) {
364 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
365 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
366
367 /* if a dimm is disabled the available capacity is zero */
368 if (!ndd)
369 return 0;
370
371 available += nd_pmem_available_dpa(nd_region, nd_mapping);
372 }
373
374 return available;
375 }
376
nd_region_allocatable_dpa(struct nd_region * nd_region)377 resource_size_t nd_region_allocatable_dpa(struct nd_region *nd_region)
378 {
379 resource_size_t avail = 0;
380 int i;
381
382 WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
383 for (i = 0; i < nd_region->ndr_mappings; i++) {
384 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
385
386 avail = min_not_zero(avail, nd_pmem_max_contiguous_dpa(
387 nd_region, nd_mapping));
388 }
389 return avail * nd_region->ndr_mappings;
390 }
391
available_size_show(struct device * dev,struct device_attribute * attr,char * buf)392 static ssize_t available_size_show(struct device *dev,
393 struct device_attribute *attr, char *buf)
394 {
395 struct nd_region *nd_region = to_nd_region(dev);
396 unsigned long long available = 0;
397
398 /*
399 * Flush in-flight updates and grab a snapshot of the available
400 * size. Of course, this value is potentially invalidated the
401 * memory nvdimm_bus_lock() is dropped, but that's userspace's
402 * problem to not race itself.
403 */
404 device_lock(dev);
405 nvdimm_bus_lock(dev);
406 wait_nvdimm_bus_probe_idle(dev);
407 available = nd_region_available_dpa(nd_region);
408 nvdimm_bus_unlock(dev);
409 device_unlock(dev);
410
411 return sprintf(buf, "%llu\n", available);
412 }
413 static DEVICE_ATTR_RO(available_size);
414
max_available_extent_show(struct device * dev,struct device_attribute * attr,char * buf)415 static ssize_t max_available_extent_show(struct device *dev,
416 struct device_attribute *attr, char *buf)
417 {
418 struct nd_region *nd_region = to_nd_region(dev);
419 unsigned long long available = 0;
420
421 device_lock(dev);
422 nvdimm_bus_lock(dev);
423 wait_nvdimm_bus_probe_idle(dev);
424 available = nd_region_allocatable_dpa(nd_region);
425 nvdimm_bus_unlock(dev);
426 device_unlock(dev);
427
428 return sprintf(buf, "%llu\n", available);
429 }
430 static DEVICE_ATTR_RO(max_available_extent);
431
init_namespaces_show(struct device * dev,struct device_attribute * attr,char * buf)432 static ssize_t init_namespaces_show(struct device *dev,
433 struct device_attribute *attr, char *buf)
434 {
435 struct nd_region_data *ndrd = dev_get_drvdata(dev);
436 ssize_t rc;
437
438 nvdimm_bus_lock(dev);
439 if (ndrd)
440 rc = sprintf(buf, "%d/%d\n", ndrd->ns_active, ndrd->ns_count);
441 else
442 rc = -ENXIO;
443 nvdimm_bus_unlock(dev);
444
445 return rc;
446 }
447 static DEVICE_ATTR_RO(init_namespaces);
448
namespace_seed_show(struct device * dev,struct device_attribute * attr,char * buf)449 static ssize_t namespace_seed_show(struct device *dev,
450 struct device_attribute *attr, char *buf)
451 {
452 struct nd_region *nd_region = to_nd_region(dev);
453 ssize_t rc;
454
455 nvdimm_bus_lock(dev);
456 if (nd_region->ns_seed)
457 rc = sprintf(buf, "%s\n", dev_name(nd_region->ns_seed));
458 else
459 rc = sprintf(buf, "\n");
460 nvdimm_bus_unlock(dev);
461 return rc;
462 }
463 static DEVICE_ATTR_RO(namespace_seed);
464
btt_seed_show(struct device * dev,struct device_attribute * attr,char * buf)465 static ssize_t btt_seed_show(struct device *dev,
466 struct device_attribute *attr, char *buf)
467 {
468 struct nd_region *nd_region = to_nd_region(dev);
469 ssize_t rc;
470
471 nvdimm_bus_lock(dev);
472 if (nd_region->btt_seed)
473 rc = sprintf(buf, "%s\n", dev_name(nd_region->btt_seed));
474 else
475 rc = sprintf(buf, "\n");
476 nvdimm_bus_unlock(dev);
477
478 return rc;
479 }
480 static DEVICE_ATTR_RO(btt_seed);
481
pfn_seed_show(struct device * dev,struct device_attribute * attr,char * buf)482 static ssize_t pfn_seed_show(struct device *dev,
483 struct device_attribute *attr, char *buf)
484 {
485 struct nd_region *nd_region = to_nd_region(dev);
486 ssize_t rc;
487
488 nvdimm_bus_lock(dev);
489 if (nd_region->pfn_seed)
490 rc = sprintf(buf, "%s\n", dev_name(nd_region->pfn_seed));
491 else
492 rc = sprintf(buf, "\n");
493 nvdimm_bus_unlock(dev);
494
495 return rc;
496 }
497 static DEVICE_ATTR_RO(pfn_seed);
498
dax_seed_show(struct device * dev,struct device_attribute * attr,char * buf)499 static ssize_t dax_seed_show(struct device *dev,
500 struct device_attribute *attr, char *buf)
501 {
502 struct nd_region *nd_region = to_nd_region(dev);
503 ssize_t rc;
504
505 nvdimm_bus_lock(dev);
506 if (nd_region->dax_seed)
507 rc = sprintf(buf, "%s\n", dev_name(nd_region->dax_seed));
508 else
509 rc = sprintf(buf, "\n");
510 nvdimm_bus_unlock(dev);
511
512 return rc;
513 }
514 static DEVICE_ATTR_RO(dax_seed);
515
read_only_show(struct device * dev,struct device_attribute * attr,char * buf)516 static ssize_t read_only_show(struct device *dev,
517 struct device_attribute *attr, char *buf)
518 {
519 struct nd_region *nd_region = to_nd_region(dev);
520
521 return sprintf(buf, "%d\n", nd_region->ro);
522 }
523
revalidate_read_only(struct device * dev,void * data)524 static int revalidate_read_only(struct device *dev, void *data)
525 {
526 nd_device_notify(dev, NVDIMM_REVALIDATE_REGION);
527 return 0;
528 }
529
read_only_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)530 static ssize_t read_only_store(struct device *dev,
531 struct device_attribute *attr, const char *buf, size_t len)
532 {
533 bool ro;
534 int rc = kstrtobool(buf, &ro);
535 struct nd_region *nd_region = to_nd_region(dev);
536
537 if (rc)
538 return rc;
539
540 nd_region->ro = ro;
541 device_for_each_child(dev, NULL, revalidate_read_only);
542 return len;
543 }
544 static DEVICE_ATTR_RW(read_only);
545
align_show(struct device * dev,struct device_attribute * attr,char * buf)546 static ssize_t align_show(struct device *dev,
547 struct device_attribute *attr, char *buf)
548 {
549 struct nd_region *nd_region = to_nd_region(dev);
550
551 return sprintf(buf, "%#lx\n", nd_region->align);
552 }
553
align_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)554 static ssize_t align_store(struct device *dev,
555 struct device_attribute *attr, const char *buf, size_t len)
556 {
557 struct nd_region *nd_region = to_nd_region(dev);
558 unsigned long val, dpa;
559 u32 mappings, remainder;
560 int rc;
561
562 rc = kstrtoul(buf, 0, &val);
563 if (rc)
564 return rc;
565
566 /*
567 * Ensure space-align is evenly divisible by the region
568 * interleave-width because the kernel typically has no facility
569 * to determine which DIMM(s), dimm-physical-addresses, would
570 * contribute to the tail capacity in system-physical-address
571 * space for the namespace.
572 */
573 mappings = max_t(u32, 1, nd_region->ndr_mappings);
574 dpa = div_u64_rem(val, mappings, &remainder);
575 if (!is_power_of_2(dpa) || dpa < PAGE_SIZE
576 || val > region_size(nd_region) || remainder)
577 return -EINVAL;
578
579 /*
580 * Given that space allocation consults this value multiple
581 * times ensure it does not change for the duration of the
582 * allocation.
583 */
584 nvdimm_bus_lock(dev);
585 nd_region->align = val;
586 nvdimm_bus_unlock(dev);
587
588 return len;
589 }
590 static DEVICE_ATTR_RW(align);
591
region_badblocks_show(struct device * dev,struct device_attribute * attr,char * buf)592 static ssize_t region_badblocks_show(struct device *dev,
593 struct device_attribute *attr, char *buf)
594 {
595 struct nd_region *nd_region = to_nd_region(dev);
596 ssize_t rc;
597
598 device_lock(dev);
599 if (dev->driver)
600 rc = badblocks_show(&nd_region->bb, buf, 0);
601 else
602 rc = -ENXIO;
603 device_unlock(dev);
604
605 return rc;
606 }
607 static DEVICE_ATTR(badblocks, 0444, region_badblocks_show, NULL);
608
resource_show(struct device * dev,struct device_attribute * attr,char * buf)609 static ssize_t resource_show(struct device *dev,
610 struct device_attribute *attr, char *buf)
611 {
612 struct nd_region *nd_region = to_nd_region(dev);
613
614 return sprintf(buf, "%#llx\n", nd_region->ndr_start);
615 }
616 static DEVICE_ATTR_ADMIN_RO(resource);
617
persistence_domain_show(struct device * dev,struct device_attribute * attr,char * buf)618 static ssize_t persistence_domain_show(struct device *dev,
619 struct device_attribute *attr, char *buf)
620 {
621 struct nd_region *nd_region = to_nd_region(dev);
622
623 if (test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags))
624 return sprintf(buf, "cpu_cache\n");
625 else if (test_bit(ND_REGION_PERSIST_MEMCTRL, &nd_region->flags))
626 return sprintf(buf, "memory_controller\n");
627 else
628 return sprintf(buf, "\n");
629 }
630 static DEVICE_ATTR_RO(persistence_domain);
631
632 static struct attribute *nd_region_attributes[] = {
633 &dev_attr_size.attr,
634 &dev_attr_align.attr,
635 &dev_attr_nstype.attr,
636 &dev_attr_mappings.attr,
637 &dev_attr_btt_seed.attr,
638 &dev_attr_pfn_seed.attr,
639 &dev_attr_dax_seed.attr,
640 &dev_attr_deep_flush.attr,
641 &dev_attr_read_only.attr,
642 &dev_attr_set_cookie.attr,
643 &dev_attr_available_size.attr,
644 &dev_attr_max_available_extent.attr,
645 &dev_attr_namespace_seed.attr,
646 &dev_attr_init_namespaces.attr,
647 &dev_attr_badblocks.attr,
648 &dev_attr_resource.attr,
649 &dev_attr_persistence_domain.attr,
650 NULL,
651 };
652
region_visible(struct kobject * kobj,struct attribute * a,int n)653 static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n)
654 {
655 struct device *dev = container_of(kobj, typeof(*dev), kobj);
656 struct nd_region *nd_region = to_nd_region(dev);
657 struct nd_interleave_set *nd_set = nd_region->nd_set;
658 int type = nd_region_to_nstype(nd_region);
659
660 if (!is_memory(dev) && a == &dev_attr_pfn_seed.attr)
661 return 0;
662
663 if (!is_memory(dev) && a == &dev_attr_dax_seed.attr)
664 return 0;
665
666 if (!is_memory(dev) && a == &dev_attr_badblocks.attr)
667 return 0;
668
669 if (a == &dev_attr_resource.attr && !is_memory(dev))
670 return 0;
671
672 if (a == &dev_attr_deep_flush.attr) {
673 int has_flush = nvdimm_has_flush(nd_region);
674
675 if (has_flush == 1)
676 return a->mode;
677 else if (has_flush == 0)
678 return 0444;
679 else
680 return 0;
681 }
682
683 if (a == &dev_attr_persistence_domain.attr) {
684 if ((nd_region->flags & (BIT(ND_REGION_PERSIST_CACHE)
685 | BIT(ND_REGION_PERSIST_MEMCTRL))) == 0)
686 return 0;
687 return a->mode;
688 }
689
690 if (a == &dev_attr_align.attr)
691 return a->mode;
692
693 if (a != &dev_attr_set_cookie.attr
694 && a != &dev_attr_available_size.attr)
695 return a->mode;
696
697 if (type == ND_DEVICE_NAMESPACE_PMEM &&
698 a == &dev_attr_available_size.attr)
699 return a->mode;
700 else if (is_memory(dev) && nd_set)
701 return a->mode;
702
703 return 0;
704 }
705
mappingN(struct device * dev,char * buf,int n)706 static ssize_t mappingN(struct device *dev, char *buf, int n)
707 {
708 struct nd_region *nd_region = to_nd_region(dev);
709 struct nd_mapping *nd_mapping;
710 struct nvdimm *nvdimm;
711
712 if (n >= nd_region->ndr_mappings)
713 return -ENXIO;
714 nd_mapping = &nd_region->mapping[n];
715 nvdimm = nd_mapping->nvdimm;
716
717 return sprintf(buf, "%s,%llu,%llu,%d\n", dev_name(&nvdimm->dev),
718 nd_mapping->start, nd_mapping->size,
719 nd_mapping->position);
720 }
721
722 #define REGION_MAPPING(idx) \
723 static ssize_t mapping##idx##_show(struct device *dev, \
724 struct device_attribute *attr, char *buf) \
725 { \
726 return mappingN(dev, buf, idx); \
727 } \
728 static DEVICE_ATTR_RO(mapping##idx)
729
730 /*
731 * 32 should be enough for a while, even in the presence of socket
732 * interleave a 32-way interleave set is a degenerate case.
733 */
734 REGION_MAPPING(0);
735 REGION_MAPPING(1);
736 REGION_MAPPING(2);
737 REGION_MAPPING(3);
738 REGION_MAPPING(4);
739 REGION_MAPPING(5);
740 REGION_MAPPING(6);
741 REGION_MAPPING(7);
742 REGION_MAPPING(8);
743 REGION_MAPPING(9);
744 REGION_MAPPING(10);
745 REGION_MAPPING(11);
746 REGION_MAPPING(12);
747 REGION_MAPPING(13);
748 REGION_MAPPING(14);
749 REGION_MAPPING(15);
750 REGION_MAPPING(16);
751 REGION_MAPPING(17);
752 REGION_MAPPING(18);
753 REGION_MAPPING(19);
754 REGION_MAPPING(20);
755 REGION_MAPPING(21);
756 REGION_MAPPING(22);
757 REGION_MAPPING(23);
758 REGION_MAPPING(24);
759 REGION_MAPPING(25);
760 REGION_MAPPING(26);
761 REGION_MAPPING(27);
762 REGION_MAPPING(28);
763 REGION_MAPPING(29);
764 REGION_MAPPING(30);
765 REGION_MAPPING(31);
766
mapping_visible(struct kobject * kobj,struct attribute * a,int n)767 static umode_t mapping_visible(struct kobject *kobj, struct attribute *a, int n)
768 {
769 struct device *dev = container_of(kobj, struct device, kobj);
770 struct nd_region *nd_region = to_nd_region(dev);
771
772 if (n < nd_region->ndr_mappings)
773 return a->mode;
774 return 0;
775 }
776
777 static struct attribute *mapping_attributes[] = {
778 &dev_attr_mapping0.attr,
779 &dev_attr_mapping1.attr,
780 &dev_attr_mapping2.attr,
781 &dev_attr_mapping3.attr,
782 &dev_attr_mapping4.attr,
783 &dev_attr_mapping5.attr,
784 &dev_attr_mapping6.attr,
785 &dev_attr_mapping7.attr,
786 &dev_attr_mapping8.attr,
787 &dev_attr_mapping9.attr,
788 &dev_attr_mapping10.attr,
789 &dev_attr_mapping11.attr,
790 &dev_attr_mapping12.attr,
791 &dev_attr_mapping13.attr,
792 &dev_attr_mapping14.attr,
793 &dev_attr_mapping15.attr,
794 &dev_attr_mapping16.attr,
795 &dev_attr_mapping17.attr,
796 &dev_attr_mapping18.attr,
797 &dev_attr_mapping19.attr,
798 &dev_attr_mapping20.attr,
799 &dev_attr_mapping21.attr,
800 &dev_attr_mapping22.attr,
801 &dev_attr_mapping23.attr,
802 &dev_attr_mapping24.attr,
803 &dev_attr_mapping25.attr,
804 &dev_attr_mapping26.attr,
805 &dev_attr_mapping27.attr,
806 &dev_attr_mapping28.attr,
807 &dev_attr_mapping29.attr,
808 &dev_attr_mapping30.attr,
809 &dev_attr_mapping31.attr,
810 NULL,
811 };
812
813 static const struct attribute_group nd_mapping_attribute_group = {
814 .is_visible = mapping_visible,
815 .attrs = mapping_attributes,
816 };
817
818 static const struct attribute_group nd_region_attribute_group = {
819 .attrs = nd_region_attributes,
820 .is_visible = region_visible,
821 };
822
823 static const struct attribute_group *nd_region_attribute_groups[] = {
824 &nd_device_attribute_group,
825 &nd_region_attribute_group,
826 &nd_numa_attribute_group,
827 &nd_mapping_attribute_group,
828 NULL,
829 };
830
831 static const struct device_type nd_pmem_device_type = {
832 .name = "nd_pmem",
833 .release = nd_region_release,
834 .groups = nd_region_attribute_groups,
835 };
836
837 static const struct device_type nd_volatile_device_type = {
838 .name = "nd_volatile",
839 .release = nd_region_release,
840 .groups = nd_region_attribute_groups,
841 };
842
is_nd_pmem(const struct device * dev)843 bool is_nd_pmem(const struct device *dev)
844 {
845 return dev ? dev->type == &nd_pmem_device_type : false;
846 }
847
is_nd_volatile(const struct device * dev)848 bool is_nd_volatile(const struct device *dev)
849 {
850 return dev ? dev->type == &nd_volatile_device_type : false;
851 }
852
nd_region_interleave_set_cookie(struct nd_region * nd_region,struct nd_namespace_index * nsindex)853 u64 nd_region_interleave_set_cookie(struct nd_region *nd_region,
854 struct nd_namespace_index *nsindex)
855 {
856 struct nd_interleave_set *nd_set = nd_region->nd_set;
857
858 if (!nd_set)
859 return 0;
860
861 if (nsindex && __le16_to_cpu(nsindex->major) == 1
862 && __le16_to_cpu(nsindex->minor) == 1)
863 return nd_set->cookie1;
864 return nd_set->cookie2;
865 }
866
nd_region_interleave_set_altcookie(struct nd_region * nd_region)867 u64 nd_region_interleave_set_altcookie(struct nd_region *nd_region)
868 {
869 struct nd_interleave_set *nd_set = nd_region->nd_set;
870
871 if (nd_set)
872 return nd_set->altcookie;
873 return 0;
874 }
875
nd_mapping_free_labels(struct nd_mapping * nd_mapping)876 void nd_mapping_free_labels(struct nd_mapping *nd_mapping)
877 {
878 struct nd_label_ent *label_ent, *e;
879
880 lockdep_assert_held(&nd_mapping->lock);
881 list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
882 list_del(&label_ent->list);
883 kfree(label_ent);
884 }
885 }
886
887 /*
888 * When a namespace is activated create new seeds for the next
889 * namespace, or namespace-personality to be configured.
890 */
nd_region_advance_seeds(struct nd_region * nd_region,struct device * dev)891 void nd_region_advance_seeds(struct nd_region *nd_region, struct device *dev)
892 {
893 nvdimm_bus_lock(dev);
894 if (nd_region->ns_seed == dev) {
895 nd_region_create_ns_seed(nd_region);
896 } else if (is_nd_btt(dev)) {
897 struct nd_btt *nd_btt = to_nd_btt(dev);
898
899 if (nd_region->btt_seed == dev)
900 nd_region_create_btt_seed(nd_region);
901 if (nd_region->ns_seed == &nd_btt->ndns->dev)
902 nd_region_create_ns_seed(nd_region);
903 } else if (is_nd_pfn(dev)) {
904 struct nd_pfn *nd_pfn = to_nd_pfn(dev);
905
906 if (nd_region->pfn_seed == dev)
907 nd_region_create_pfn_seed(nd_region);
908 if (nd_region->ns_seed == &nd_pfn->ndns->dev)
909 nd_region_create_ns_seed(nd_region);
910 } else if (is_nd_dax(dev)) {
911 struct nd_dax *nd_dax = to_nd_dax(dev);
912
913 if (nd_region->dax_seed == dev)
914 nd_region_create_dax_seed(nd_region);
915 if (nd_region->ns_seed == &nd_dax->nd_pfn.ndns->dev)
916 nd_region_create_ns_seed(nd_region);
917 }
918 nvdimm_bus_unlock(dev);
919 }
920
921 /**
922 * nd_region_acquire_lane - allocate and lock a lane
923 * @nd_region: region id and number of lanes possible
924 *
925 * A lane correlates to a BLK-data-window and/or a log slot in the BTT.
926 * We optimize for the common case where there are 256 lanes, one
927 * per-cpu. For larger systems we need to lock to share lanes. For now
928 * this implementation assumes the cost of maintaining an allocator for
929 * free lanes is on the order of the lock hold time, so it implements a
930 * static lane = cpu % num_lanes mapping.
931 *
932 * In the case of a BTT instance on top of a BLK namespace a lane may be
933 * acquired recursively. We lock on the first instance.
934 *
935 * In the case of a BTT instance on top of PMEM, we only acquire a lane
936 * for the BTT metadata updates.
937 */
nd_region_acquire_lane(struct nd_region * nd_region)938 unsigned int nd_region_acquire_lane(struct nd_region *nd_region)
939 {
940 unsigned int cpu, lane;
941
942 migrate_disable();
943 cpu = smp_processor_id();
944 if (nd_region->num_lanes < nr_cpu_ids) {
945 struct nd_percpu_lane *ndl_lock, *ndl_count;
946
947 lane = cpu % nd_region->num_lanes;
948 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
949 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
950 if (ndl_count->count++ == 0)
951 spin_lock(&ndl_lock->lock);
952 } else
953 lane = cpu;
954
955 return lane;
956 }
957 EXPORT_SYMBOL(nd_region_acquire_lane);
958
nd_region_release_lane(struct nd_region * nd_region,unsigned int lane)959 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane)
960 {
961 if (nd_region->num_lanes < nr_cpu_ids) {
962 unsigned int cpu = smp_processor_id();
963 struct nd_percpu_lane *ndl_lock, *ndl_count;
964
965 ndl_count = per_cpu_ptr(nd_region->lane, cpu);
966 ndl_lock = per_cpu_ptr(nd_region->lane, lane);
967 if (--ndl_count->count == 0)
968 spin_unlock(&ndl_lock->lock);
969 }
970 migrate_enable();
971 }
972 EXPORT_SYMBOL(nd_region_release_lane);
973
974 /*
975 * PowerPC requires this alignment for memremap_pages(). All other archs
976 * should be ok with SUBSECTION_SIZE (see memremap_compat_align()).
977 */
978 #define MEMREMAP_COMPAT_ALIGN_MAX SZ_16M
979
default_align(struct nd_region * nd_region)980 static unsigned long default_align(struct nd_region *nd_region)
981 {
982 unsigned long align;
983 u32 remainder;
984 int mappings;
985
986 align = MEMREMAP_COMPAT_ALIGN_MAX;
987 if (nd_region->ndr_size < MEMREMAP_COMPAT_ALIGN_MAX)
988 align = PAGE_SIZE;
989
990 mappings = max_t(u16, 1, nd_region->ndr_mappings);
991 div_u64_rem(align, mappings, &remainder);
992 if (remainder)
993 align *= mappings;
994
995 return align;
996 }
997
998 static struct lock_class_key nvdimm_region_key;
999
nd_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc,const struct device_type * dev_type,const char * caller)1000 static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
1001 struct nd_region_desc *ndr_desc,
1002 const struct device_type *dev_type, const char *caller)
1003 {
1004 struct nd_region *nd_region;
1005 struct device *dev;
1006 unsigned int i;
1007 int ro = 0;
1008
1009 for (i = 0; i < ndr_desc->num_mappings; i++) {
1010 struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1011 struct nvdimm *nvdimm = mapping->nvdimm;
1012
1013 if ((mapping->start | mapping->size) % PAGE_SIZE) {
1014 dev_err(&nvdimm_bus->dev,
1015 "%s: %s mapping%d is not %ld aligned\n",
1016 caller, dev_name(&nvdimm->dev), i, PAGE_SIZE);
1017 return NULL;
1018 }
1019
1020 if (test_bit(NDD_UNARMED, &nvdimm->flags))
1021 ro = 1;
1022
1023 }
1024
1025 nd_region =
1026 kzalloc(struct_size(nd_region, mapping, ndr_desc->num_mappings),
1027 GFP_KERNEL);
1028
1029 if (!nd_region)
1030 return NULL;
1031 nd_region->ndr_mappings = ndr_desc->num_mappings;
1032 /* CXL pre-assigns memregion ids before creating nvdimm regions */
1033 if (test_bit(ND_REGION_CXL, &ndr_desc->flags)) {
1034 nd_region->id = ndr_desc->memregion;
1035 } else {
1036 nd_region->id = memregion_alloc(GFP_KERNEL);
1037 if (nd_region->id < 0)
1038 goto err_id;
1039 }
1040
1041 nd_region->lane = alloc_percpu(struct nd_percpu_lane);
1042 if (!nd_region->lane)
1043 goto err_percpu;
1044
1045 for (i = 0; i < nr_cpu_ids; i++) {
1046 struct nd_percpu_lane *ndl;
1047
1048 ndl = per_cpu_ptr(nd_region->lane, i);
1049 spin_lock_init(&ndl->lock);
1050 ndl->count = 0;
1051 }
1052
1053 for (i = 0; i < ndr_desc->num_mappings; i++) {
1054 struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1055 struct nvdimm *nvdimm = mapping->nvdimm;
1056
1057 nd_region->mapping[i].nvdimm = nvdimm;
1058 nd_region->mapping[i].start = mapping->start;
1059 nd_region->mapping[i].size = mapping->size;
1060 nd_region->mapping[i].position = mapping->position;
1061 INIT_LIST_HEAD(&nd_region->mapping[i].labels);
1062 mutex_init(&nd_region->mapping[i].lock);
1063
1064 get_device(&nvdimm->dev);
1065 }
1066 nd_region->provider_data = ndr_desc->provider_data;
1067 nd_region->nd_set = ndr_desc->nd_set;
1068 nd_region->num_lanes = ndr_desc->num_lanes;
1069 nd_region->flags = ndr_desc->flags;
1070 nd_region->ro = ro;
1071 nd_region->numa_node = ndr_desc->numa_node;
1072 nd_region->target_node = ndr_desc->target_node;
1073 ida_init(&nd_region->ns_ida);
1074 ida_init(&nd_region->btt_ida);
1075 ida_init(&nd_region->pfn_ida);
1076 ida_init(&nd_region->dax_ida);
1077 dev = &nd_region->dev;
1078 dev_set_name(dev, "region%d", nd_region->id);
1079 dev->parent = &nvdimm_bus->dev;
1080 dev->type = dev_type;
1081 dev->groups = ndr_desc->attr_groups;
1082 dev->of_node = ndr_desc->of_node;
1083 nd_region->ndr_size = resource_size(ndr_desc->res);
1084 nd_region->ndr_start = ndr_desc->res->start;
1085 nd_region->align = default_align(nd_region);
1086 if (ndr_desc->flush)
1087 nd_region->flush = ndr_desc->flush;
1088 else
1089 nd_region->flush = NULL;
1090
1091 device_initialize(dev);
1092 lockdep_set_class(&dev->mutex, &nvdimm_region_key);
1093 nd_device_register(dev);
1094
1095 return nd_region;
1096
1097 err_percpu:
1098 if (!test_bit(ND_REGION_CXL, &ndr_desc->flags))
1099 memregion_free(nd_region->id);
1100 err_id:
1101 kfree(nd_region);
1102 return NULL;
1103 }
1104
nvdimm_pmem_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc)1105 struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
1106 struct nd_region_desc *ndr_desc)
1107 {
1108 ndr_desc->num_lanes = ND_MAX_LANES;
1109 return nd_region_create(nvdimm_bus, ndr_desc, &nd_pmem_device_type,
1110 __func__);
1111 }
1112 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
1113
nvdimm_volatile_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc)1114 struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
1115 struct nd_region_desc *ndr_desc)
1116 {
1117 ndr_desc->num_lanes = ND_MAX_LANES;
1118 return nd_region_create(nvdimm_bus, ndr_desc, &nd_volatile_device_type,
1119 __func__);
1120 }
1121 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);
1122
nvdimm_region_delete(struct nd_region * nd_region)1123 void nvdimm_region_delete(struct nd_region *nd_region)
1124 {
1125 if (nd_region)
1126 nd_device_unregister(&nd_region->dev, ND_SYNC);
1127 }
1128 EXPORT_SYMBOL_GPL(nvdimm_region_delete);
1129
nvdimm_flush(struct nd_region * nd_region,struct bio * bio)1130 int nvdimm_flush(struct nd_region *nd_region, struct bio *bio)
1131 {
1132 int rc = 0;
1133
1134 if (!nd_region->flush)
1135 rc = generic_nvdimm_flush(nd_region);
1136 else {
1137 if (nd_region->flush(nd_region, bio))
1138 rc = -EIO;
1139 }
1140
1141 return rc;
1142 }
1143 /**
1144 * generic_nvdimm_flush() - flush any posted write queues between the cpu and pmem media
1145 * @nd_region: interleaved pmem region
1146 */
generic_nvdimm_flush(struct nd_region * nd_region)1147 int generic_nvdimm_flush(struct nd_region *nd_region)
1148 {
1149 struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev);
1150 int i, idx;
1151
1152 /*
1153 * Try to encourage some diversity in flush hint addresses
1154 * across cpus assuming a limited number of flush hints.
1155 */
1156 idx = this_cpu_read(flush_idx);
1157 idx = this_cpu_add_return(flush_idx, hash_32(current->pid + idx, 8));
1158
1159 /*
1160 * The pmem_wmb() is needed to 'sfence' all
1161 * previous writes such that they are architecturally visible for
1162 * the platform buffer flush. Note that we've already arranged for pmem
1163 * writes to avoid the cache via memcpy_flushcache(). The final
1164 * wmb() ensures ordering for the NVDIMM flush write.
1165 */
1166 pmem_wmb();
1167 for (i = 0; i < nd_region->ndr_mappings; i++)
1168 if (ndrd_get_flush_wpq(ndrd, i, 0))
1169 writeq(1, ndrd_get_flush_wpq(ndrd, i, idx));
1170 wmb();
1171
1172 return 0;
1173 }
1174 EXPORT_SYMBOL_GPL(nvdimm_flush);
1175
1176 /**
1177 * nvdimm_has_flush - determine write flushing requirements
1178 * @nd_region: interleaved pmem region
1179 *
1180 * Returns 1 if writes require flushing
1181 * Returns 0 if writes do not require flushing
1182 * Returns -ENXIO if flushing capability can not be determined
1183 */
nvdimm_has_flush(struct nd_region * nd_region)1184 int nvdimm_has_flush(struct nd_region *nd_region)
1185 {
1186 int i;
1187
1188 /* no nvdimm or pmem api == flushing capability unknown */
1189 if (nd_region->ndr_mappings == 0
1190 || !IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API))
1191 return -ENXIO;
1192
1193 /* Test if an explicit flush function is defined */
1194 if (test_bit(ND_REGION_ASYNC, &nd_region->flags) && nd_region->flush)
1195 return 1;
1196
1197 /* Test if any flush hints for the region are available */
1198 for (i = 0; i < nd_region->ndr_mappings; i++) {
1199 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1200 struct nvdimm *nvdimm = nd_mapping->nvdimm;
1201
1202 /* flush hints present / available */
1203 if (nvdimm->num_flush)
1204 return 1;
1205 }
1206
1207 /*
1208 * The platform defines dimm devices without hints nor explicit flush,
1209 * assume platform persistence mechanism like ADR
1210 */
1211 return 0;
1212 }
1213 EXPORT_SYMBOL_GPL(nvdimm_has_flush);
1214
nvdimm_has_cache(struct nd_region * nd_region)1215 int nvdimm_has_cache(struct nd_region *nd_region)
1216 {
1217 return is_nd_pmem(&nd_region->dev) &&
1218 !test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags);
1219 }
1220 EXPORT_SYMBOL_GPL(nvdimm_has_cache);
1221
is_nvdimm_sync(struct nd_region * nd_region)1222 bool is_nvdimm_sync(struct nd_region *nd_region)
1223 {
1224 if (is_nd_volatile(&nd_region->dev))
1225 return true;
1226
1227 return is_nd_pmem(&nd_region->dev) &&
1228 !test_bit(ND_REGION_ASYNC, &nd_region->flags);
1229 }
1230 EXPORT_SYMBOL_GPL(is_nvdimm_sync);
1231
1232 struct conflict_context {
1233 struct nd_region *nd_region;
1234 resource_size_t start, size;
1235 };
1236
region_conflict(struct device * dev,void * data)1237 static int region_conflict(struct device *dev, void *data)
1238 {
1239 struct nd_region *nd_region;
1240 struct conflict_context *ctx = data;
1241 resource_size_t res_end, region_end, region_start;
1242
1243 if (!is_memory(dev))
1244 return 0;
1245
1246 nd_region = to_nd_region(dev);
1247 if (nd_region == ctx->nd_region)
1248 return 0;
1249
1250 res_end = ctx->start + ctx->size;
1251 region_start = nd_region->ndr_start;
1252 region_end = region_start + nd_region->ndr_size;
1253 if (ctx->start >= region_start && ctx->start < region_end)
1254 return -EBUSY;
1255 if (res_end > region_start && res_end <= region_end)
1256 return -EBUSY;
1257 return 0;
1258 }
1259
nd_region_conflict(struct nd_region * nd_region,resource_size_t start,resource_size_t size)1260 int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
1261 resource_size_t size)
1262 {
1263 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
1264 struct conflict_context ctx = {
1265 .nd_region = nd_region,
1266 .start = start,
1267 .size = size,
1268 };
1269
1270 return device_for_each_child(&nvdimm_bus->dev, &ctx, region_conflict);
1271 }
1272
1273 MODULE_IMPORT_NS("DEVMEM");
1274